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Book ChapterThe contribution of intestinal epithelium to the innate immune system includes detect... more Book ChapterThe contribution of intestinal epithelium to the innate immune system includes detecting luminal microbes, transducing signals, and activating inflammatory mediator release by epithelial and other cells of the immune system like the antigen presenting cells. Microbial antigens are detected by cells of the innate immune system through their pattern recognition receptors (PRRs). The PRRs recognize microbe-associated molecular patterns and generate signals that activate transcription pathways like nuclear factor kappa B and mitogen activated protein kinases. This activation leads to production of inflammatory and growth mediators that drive the immune system to elicit tolerance or immune response designated at maintaining immune homeostasis. Key to this signaling is the gut microbiota. Intestinal epithelial cell sensing of optimally balanced microbiota favors immune homeostasis whereas sensing under disrupted microbiota impairs immune function and predisposes to disease. Un...

Proceeding of the 35 scientific conference of Tanzania veterinary Association, Vol. 35: 147-152A ... more Proceeding of the 35 scientific conference of Tanzania veterinary Association, Vol. 35: 147-152A 4-year-old East African black headed ewe was presented to Sokoine University of Agriculture Animal Hospital with a history of loss of body condition and respiratory distress. Clinical examination revealed poor body condition, severe leukopenia with neutrophilia and lymphopenia. Radiographic examination of the thorax revealed an elongated caudal mediastinal mass with soft tissue opacity dorsal to caudal vena cava and caudal to the carina. The ewe was humanely euthanised due to deteriorated body condition. At post-mortem examination the mass contained caseous creamy material with early laminated appearance surrounded by a whitish fibrous capsule suggestive of chronic abscessation of caudal mediastinal lymph node. Corynebacterium pseudotuberculosis was isolated on bacterial culture of pus sample. A diagnosis of an abscessed caudal mediastinal lymph node as a result of Corynebacterium pseudo...

Book ChapterThe digestive system, which extends from the mouth to the anus, is responsible for re... more Book ChapterThe digestive system, which extends from the mouth to the anus, is responsible for receiving food, breaking it down into nutrients (digestion), absorbing the nutrients into the bloodstream, and eliminating the undigestible parts of food from the body. It consists of the mouth, throat, esophagus, stomach, small intestine, large intestine, rectum, and the anus. In addition, the digestive system consists of accessory digestive glands namely the liver, exocrine pancreas, and the biliary system consisting of the gallbladder and the bile duct. Disorders of the gastrointestinal system can be divided into: 1. Upper gastrointestinal disorders which involve diseases of the oral cavity, esophagus, and the stomach. Disorders of the oral cavity include those in the mouth, parotid and other salivary glands, and the pharynx. 2. Intestinal disorders which include disorders of the small intestine, large intestine, those involving both small and large intestine, rectum, and the anus. Conditions affecting the small intestine include conditions like enteritis (duodenitis, jejunitis, ileitis), duodenal (peptic) ulcer, and malabsorption. Those affecting the large intestine include appendicitis, colitis, functional colonic disease (e.g. irritable bowel syndrome, intestinal pseudoobstruction), megacolon, and diverticular disease. Examples of conditions occurring in both large and small intestines are enterocolitis and Crohn’s disease. Conditions affecting the rectum and the anus include proctitis, rectal prolapsed, anorectal fistula/fissure, and hemorrhoids. 3. Accessory digestive gland disorders are disorders of the liver, exocrine pancreas, gallbladder and bile duct. Examples of conditions affecting the liver include disorders of the liver parenchyma such as acute viral hepatitis (hepatitis A,B,C,D,E), yellow fever, cirrhosis, haemochromatosis and tumors like hepatocellular carcinoma. The biliary system could suffer from cholecystitis, gallstones, and cholesterolosis whereas the exocrine pancreas may have developmental abnormalities, pancreatitis, and pancreatic insufficiency. Owing to the nature and location of the condition, symptoms and subsequent treatment and prevention vary significantly. In general terms, congenital disorders may need surgical correction while infectious cases need antimicrobial therapy following identification of specific causative agents. Most of the gastrointestinal disorders are treated symptomatically. In this case, therapy is instituted to correct effects of symptoms such as vomiting and diarrhea (antiemetics, oral rehydration salts, intravenous fluid infusion) or muscular disorders like esophageal spasms where long acting anticholinergics or calcium blockers such as nifedipine relief the symptoms. Thus use of antimicrobials, surgery, and symptomatic therapy are major approaches to treatment of gastrointestinal disorders. Apart from congenital and inherited disorders, many gastrointestinal conditions can be prevented by proper and safe nutrition as well as drinking of safe water. Some specific conditions, such as gastritis, gastric and duodenal ulcers, inflammatory bowel diseases, cirrhosis, liver failure, and pancreatitis may need very special attention for treatment. In this book chapter, current findings on research and medical practice on symptoms, treatment and prevention of specific gastrointestinal disorders will be described in detail

Book Chapter, Chapter 7According to hygiene hypothesis, diseases of the immune system are increas... more Book Chapter, Chapter 7According to hygiene hypothesis, diseases of the immune system are increasing with socio-economic and sanitary conditions. This is evidenced by high incidences of allergic and autoimmune diseases in Western countries than in developing countries. The underlying factor is disruption of normal microbiota and their associated beneficial effects on intestinal mucosal immunity. Thus the pathogeneses of these disorders appear to revolve around impaired ability of the intestinal microbiota to effectively modulate and thus balance the body immune responses. As a result the immune system reacts excessively to antigens that would otherwise be tolerated and thus results in allergic reactions. Alternatively, the immune system reacts to self-antigens to cause autoimmune diseases. Some of these disorders are characterized by persistent production of inflammatory mediators leading to chronic inflammation and tissue damage. Several reports have indicated that oral administration of excessive numbers of selected members of microbiota, so called probiotic bacteria, prevents, treats, and improves the conditions of patients with immune-mediated disorders like allergy, inflammatory bowel diseases, and type 1 diabetes mellitus. Current knowledge suggests that probiotic bacteria mediate their beneficial effects via modulation of the immune system to balance its responses and institute protection. Herein the knowledge of new research on the role of probiotic bacteria on the development of some of the immune mediated diseases is reviewed in order to provide an insight in the role of probiotics in health and disease

Tienda online donde Comprar Probiotic bacteria and enteric infections. Cytoprotection by probioti... more Tienda online donde Comprar Probiotic bacteria and enteric infections. Cytoprotection by probiotic bacteria al precio 152,99 € de J. Malago | J. Koninkx | R. Marinsek-Logar, tienda de Libros de Medicina, Libros de Medicina Familiar y Comunitaria/General - Medicina general

International Journal of Sciences: Basic and Applied Research, 2018

Cellular response to stress leads to production of heat shock proteins (Hsps) that are protective... more Cellular response to stress leads to production of heat shock proteins (Hsps) that are protective against various perturbations including stress, infection and inflammation. The liver is a victim to many body disturbances including intoxications and systemic diseases. Stemming on the ability of Hsps to protect an array of perturbations in various body systems, it is justifiable to explore their protective potency to the rat model of carbon tetrachloride (CTC)-induced hepatic toxicity. The current study therefore aimed at testing whether prior induction of Hsp90 could protect the liver against CTC. Rats were exposed to zinc sulphate (ZS) to induce Hsp90 then CTC for 8, 24, 48 or 72 hr. At the end of treatment, rats were sacrificed, autopsied, liver samples taken and fixed in formalin and routinely processed. Sectioned tissues were stained with hematoxylin and eosin or anti-Hsp90 monoclonal antibodies to assess morphological changes and Hsp90 expression respectively. CTC induced damag...

The large number of microbials in the intestine that overrides the total human cells by ten folds... more The large number of microbials in the intestine that overrides the total human cells by ten folds alludes to significant contribution of the microbiota to human health. This is vivid in enteric and some systemic diseases emanating from disruption of the microbiota. The microbiota influences the development and functioning of both, innate and acquired immune systems for gut health. The effect of microbiota spills throughout the various components of the gut immune systems from “primitive” non specific pattern recognition receptors (PRR) to most specific adaptive T cell responses. To induce immune responses, commensal microbes are recognized by PRRs, which in turn regulate mucosal innate immunity and inflammatory responses. PRRs detect microbe-associated molecular patterns (MAMPs or "infectious non-self") or endogenous "danger signals" derived from stressed, damaged or infected tissue to stimulate the intestinal innate immunity that initiates adaptive immune responses. MAMPs include peptidoglycans, lipoproteins, lipopolysaccharides, teichoic acids, CpG DNA motif, double strand RNA and flagellin. In a balanced microbiota profile, PRR signaling ensures immune homeostasis and protects the host against enteral pathogens. Chapter one of this book will discuss the influence of the microbiota to PRR signaling during health and disease for intestinal immunity. Chapter two of the book focuses on a second level of innate immune system. This involves cells of the innate immune system that are responsible for driving non-specific innate immunity. They include natural killer cells, mast cells, eosinophils, basophils and the phagocytic cells including macrophages, neutrophils and dendritic cells. However, owing to the great commitment of macrophages and dendritic cells, a separate chapter for these two phagocytic cell types is allocated. Thus chapter two discusses the influence of microbiota on innate cells engendering intestinal immunity under health and disease. It concludes the innate immune system of the intestine. Macrophages and dendritic cells are professional antigen presenting cells. They sample antigens from the intestinal lumen, process, and present them to cells of the adaptive immune system. Despite of enormous types of enteral antigens ranging from harmful to beneficial, the antigen presenting cells are capable of efficiently discriminating them and driving respective responses to effector cells of the adaptive immune system. While dendritic cells are capable of priming T cell responses, macrophages do polarize the responses. As to how the microbiota influences the functioning of these cells, chapter three is devoted to discuss that phenomenon. The chapter links innate and adaptive intestinal immune systems since macrophages and dendritic cells lie in the interface between innate and adaptive immune systems. The acquired or adaptive immunity of the gut is split in humoral and cellular components. The humoral immune system is mainly geared by gut-associated lymphoid tissue (GALT) whose components include effector (i.e. epithelial lymphocytes and lamina propria) and inductive (i.e. mesenteric lymph nodes, Peyer’s patches, isolated lymphoid follicles, and cryptopatches) sites. It is interesting to note that microbiota influences GALT development and functioning during health and diseases. In germ free animals and those with disrupted microbita, GALT functioning is heavily compromised leading to diseases. Restoration of normal microbiotal profile to such individuals cures the disorders. Chapter four of this book will describe how the microbiota interacts with GALT and other components of the humoral immune system to maintain intestinal immunity under health and disease. The last chapter, chapter 5, focuses on the second part of the adaptive immune system which is cellular immune system. This system is dominated by several CD4 and CD8 lymphocytes that drive the cellular adaptive immune system. The main components are CD4+ cells which include T helper and regulatory T cells. Other T cells include cytotoxic T, memory, natural killer, and mucosa associated invariant T cells. While T helper cells drive most of the inflammatory responses, regulatory T cells downregulate these responses. As such, they are considered potential therapeutic agents of the future. Current knowledge indicates that the functioning of most, if not all, T cells is influenced by the microbiota. Chapter 5 is therefore devoted to discuss how the microbiota interacts with T cells during health and disease to foster intestinal immunity. In the past few years we have encountered mounting evidence showing that the microbiota plays essential role in regulating and maintaining host’s intestinal immunity. This is done through various ways including; regulation of mucin gene expression by goblet cells, modification of glycosylation of mucus to interfere with bacterial adhesion, colonization and invasion, induction of secretion of antimicrobial peptides by…

International Journal of Sciences: Basic and Applied Research, 2018

Heat shock response is rapidly induced to protect cells from irreversible injury by stabilizing c... more Heat shock response is rapidly induced to protect cells from irreversible injury by stabilizing cellular synthetic and metabolic activities. Particularly, the response differentially protects against stresses, infections and inflammations. While it could be time- and tissue-dependent, it is not established as to how it exhibits. This study explored the expression of heat shock protein (Hsp) 27, 70 and 90 in intestines, kidneys, livers and lungs of mice undergoing hyperthermia at 42 ° C for 1 hr and recovering for 1-72 hr. The expression of these Hsps was determined by immunohistochemical staining of formalin-fixed paraffin-embedded tissue sections. There was an increase in the expression of Hsp27, 70 and 90 that peaked at 6-12 hr and differentially declined at 48-72 hr. The peak expression was reached earlier in the lung and dropped sharply in the intestine while sustained for a longer time in the liver and kidney. At 72 hr only Hsp90 exhibited moderate expression in the lung and ki...

Tanzania Veterinary Journal, 2018

Macrophages, dendritic cells (DCs) and to less extent B cells are professional antigen presenting... more Macrophages, dendritic cells (DCs) and to less extent B cells are professional antigen presenting cells (APCs). They sample antigens from the intestinal lumen, process, and present them to cells of the adaptive immune system. While DCs are capable of priming T cell responses, macrophages do polarize the responses. The intestinal lumen contains diverse range of antigens from food proteins, microbiota, and pathogenic microbes that constantly challenge the immune system. While antigens from food proteins and microbiota are not harmful, those from pathogenic microbes are detrimental to the body. The immune system detects both types of antigens and drives immune responses geared at inducing tolerance or reaction to maintain immune homeostasis. Uptake of these antigens is done by the APCs. These cells present antigens to effector cells of the adaptive immune system which generate responses corresponding to particular antigen. The microbiota influences the nature and type of responses gene...

Health Care : Current Reviews, 2018

Despite the efforts to minimize malaria infection in Tanzania, its prevalence persists. To what f... more Despite the efforts to minimize malaria infection in Tanzania, its prevalence persists. To what factors is the persistence be attributed? Does people's lack of knowledge, impact negatively on their receptivity of malarial preventive and control strategies? This paper examines knowledge about control strategies of malaria, both curative and preventive, among local native of Lindi Urban district, in Tanzania, with the specific objectives to determine people's knowledge about malaria control strategies. Both qualitative and quantitative data were collected from 356 respondents. Focus group discussion were employed in eliciting qualitative information whereas a structured questionnaire was utilized to collect quantitative data. Both descriptive and inferential statistics were used in the analysis of these data. Descriptive analyses involved computation of frequency and percentages. Inferential measures were determined through Chi-square test. Knowledge of participants was significantly associated (P<0.05) with educational level, location of respondents, marital status and occupation. As such, knowledge about malaria control strategies in the study district was much different between respondents who had different socioeconomic factors. However, there was insignificant association (P>0.05) between malarial knowledge, sex, age of respondents and total number of members per household. Conclusively, this paper found that participants had information about malaria preventive strategies; they hardly had knowledge about the cause of malaria, importance of using mosquito nets consistently in protecting themselves from disease, and had no knowledge about how to integrate as well as implement various malaria preventative measures. Additionally, some misconceptions among respondents were discerned regarding cure of malaria, symptoms, and the effectiveness of bed nets.

Journal of Zhejiang University. Science. B, 2015

Intrarectal infusion of butyrate improves colorectal disorders including ulcerative colitis (UC).... more Intrarectal infusion of butyrate improves colorectal disorders including ulcerative colitis (UC). However, it is not established whether systemically administered butyrate benefits such patients. The current study aimed at exploring and comparing the potential of intraperitoneally, intrarectally, and orally administered butyrate against acetic acid (AA)-induced UC in rats. Intrarectal administration of 2 ml of 50% AA was done after or without prior treatment of rats for 7 consecutive days with 100 mg/kg sodium butyrate (SB) intraperitoneally, intrarectally, or orally. Rats were sacrificed after 48 h of AA-treatment. Subsequently, colon sections were processed routinely for histopathological examination. We clinically observed diarrhea, loose stools, and hemoccult-positive stools, and histologically, epithelial loss and ulceration, crypt damage, goblet cell depletion, hemorrhage, and mucosal infiltration of inflammatory cells. The changes were significantly reduced by intraperitoneal...

Beneficial microbes, 2010

Invasion of the gut by pathogenic Salmonella leads to production of IL-8 that initiates inflammat... more Invasion of the gut by pathogenic Salmonella leads to production of IL-8 that initiates inflammatory reactions to combat the bacterium. However, its persistent production causes tissue damage and interventions that suppress IL-8 production prevent tissue damage. We hypothesised that probiotics could mediate their benefits via inhibition of IL-8 synthesis. Caco-2 cells were infected with probiotic Bifidobacterium infantis W52, Lactobacillus casei W56, Lactococcus lactis W58, Lactobacillus acidophilus W70, Bifidobacterium bifidum W23, or Lactobacillus salivarius W24 or pathogenic Salmonella enterica serovar Enteritidis 857 at 0, 0.2, 1, 2, 10, 20, 100 or 200 bacterial cells/Caco-2 cell for 1 hour. Cells were also exposed to a combination of one probiotic bacterium (200 bacterial cells/Caco-2 cell) and the graded numbers of Salmonella as either co-incubation (1 hour) or pre-incubation of the probiotic bacterium (1 hour) followed by Salmonella (1 hour). The cells recovered for 2 or 24 h...

Journal of Zhejiang University. Science. B, 2008

The histopathological features and the associated clinical findings of ulcerative colitis (UC) ar... more The histopathological features and the associated clinical findings of ulcerative colitis (UC) are due to persistent inflammatory response in the colon mucosa. Interventions that suppress this response benefit UC patients. We tested whether sodium arsenite (SA) benefits rats with dextran sulfate sodium (DSS)-colitis. The DSS-colitis was induced by 5% DSS in drinking water. SA (10 mg/kg; intraperitoneally) was given 8 h before DSS treatment and then every 48 h for 3 cycles of 7, 14 or 21 d. At the end of each cycle rats were sacrificed and colon sections processed for histological examination. DSS induced diarrhea, loose stools, hemoccult positive stools, gross bleeding, loss of body weight, loss of epithelium, crypt damage, depletion of goblet cells and infiltration of inflammatory cells. The severity of these changes increased in the order of Cycles 1, 2 and 3. Treatment of rats with SA significantly reduced this severity and improved the weight gain.

Tanzania Veterinary Journal, 2009

Theileriosis, in particular East Coast Fever, remains to be a challenge to herdsmen in Eastern, C... more Theileriosis, in particular East Coast Fever, remains to be a challenge to herdsmen in Eastern, Central and Southern Africa. Its treatment cost is unbearable to majority of rural poor keepers who have subsequently opted for alternatives. Some herdsmen have developed a practice of heat application to parotid and prescapular lymph nodes of cattle with theileriosis to treat the disorder. The approach has been beneficial from time immemorial. Although the actual mechanism of this approach remains enigmatic, it might be linked with the protective role of heat shock response observed in several conditions. This prompts for closer look into the possible protective mechanisms of heat shock response against theileriosis. By gaining insight into how the heat shock response protects hosts against infections and its potential to protect cattle against theileriosis, therapeutic approaches to combat theileriosis could be improved. This work therefore, explores the cellular events triggered by Theileria parasite in the host cell as well as the possible sites at which heat shock response interferes to prevent establishment of the parasite and development of clinical theileriosis. It is concluded that the heat shock response is beneficial to animals against theileriosis. This concept can serve as a prelude to new therapeutic approaches against theileriosis. Keywords : Theileriosis, T. parva, NF-κB, Hsps, apoptosis Tanzania Vet Journal Vol. 25 (2) 2008: pp. 75-87

Tanzania Veterinary Journal, 2009

The local chicken has profound potential for upgrading through cross breeding with improved comme... more The local chicken has profound potential for upgrading through cross breeding with improved commercial birds to increase meat and egg production. This study aimed at evaluating egg traits, hatchability, fertility, chick hatch weight, and chick survivability of commercial Rhode Island Red (RIR), local, and crossbred chickens. A total of 6752 local chicken eggs were collected to obtain breeding stock and to study egg traits. RIR breeding stock was obtained from raising 250 (50 males, 200 females) while crossbred chickens were obtained by crossing RIR layer cocks to local hens and vice versa. A total of 1382, 1523, and 1476 local, RIR, and crossbred chicken eggs respectively were assessed for egg weight, length, breadth, and volume as well as chick hatch weight. Fertility and hatchability were assessed in 3675 local chicken eggs and 3350 eggs from RIR and crossbred chicken each. There was no significant difference (p < 0.05) in egg traits and chick hatch weight between RIR and crossbred chickens but these birds had significantly higher egg weight, egg length, egg breadth, egg volume, and chick hatch weight than local chickens. There were significant (p < 0.0001) positive relationships between egg volume and egg weight, chick hatch weight and egg weight, and chick hatch weight and egg volume for all chickens. Fertility was 92.0±4.14, 91.1±4.42, and 94.5±2.21 for local, RIR, and crossbred chickens respectively. Hatchability varied significantly at p<0.05 (80.6±1.43 in crossbred, 64.0±2.16 in RIR, and 52.2±2.54 in local chickens). Survivability of local chicks was superior by 50% over RIR and crossbred chicks. It is concluded that cross breeding local chickens to RIR produces a superior breed to local ecotype in terms of egg traits, hatchability and survivability. Such superiority can be exploited to upgrade the genetic potential of local ecotype and thus improve poultry production.

Probiotic Bacteria and Enteric Infections, 2011

The gut microbiota is part and parcel of the innate immunity that protects the host against enter... more The gut microbiota is part and parcel of the innate immunity that protects the host against enteric pathogens. Soon after birth, its composition starts to establish in the infant depending upon the method of delivery and the environment. Factors like nutrition, antimicrobial usage, age, changes in intestinal motility, behavioural changes, and several others, subsequently affect the individual’s microbiotal composition throughout

Beneficial Microbes, 2015

The large number of intestinal microorganisms, which exceeds the total number of human cells by t... more The large number of intestinal microorganisms, which exceeds the total number of human cells by ten folds, alludes to a significant contribution to human health. This is vivid in enteric and some systemic diseases emanating from disruption of the microbiota. As life style keeps shifting towards disruption of the microbiota in most societies worldwide, interest in the contribution of the microbiota to gut health has grown enormously. Many studies have been conducted to elucidate the exact contribution of the microbiota to human health. The knowledge gained from these studies indicates that the microbiota interacts with the intestinal milieu to maintain gut health. In this review, the crosstalk of microbiota with the intestinal physicochemical barrier pivotal to the gut innate immunity is highlighted. In particular, the review focuses on the role of the microbiota on competitive exclusion of pathogens, intestinal pH, epithelial mechanical barrier integrity, apical actin cytoskeleton, ...

Probiotic Bacteria and Enteric Infections, 2011

... Cytoprotection Joshua J. Malago and Jos FJG Koninkx JJ Malago (???) Department of Veterinary ... more ... Cytoprotection Joshua J. Malago and Jos FJG Koninkx JJ Malago (???) Department of Veterinary Pathology, Faculty of Veterinary Medicine, Sokoine University of Agriculture, PO Box 3203, Chuo Kikuu, Morogoro, Tanzania e-mail: malagojj@yahoo.com Page 2. 290 ...

Tanzania Veterinary Journal, 2008

Short chain fatty acids are increasingly used as food additives due to the health benefits they h... more Short chain fatty acids are increasingly used as food additives due to the health benefits they have. Recently, they have been implicated in protecting patients against intestinal disorders but without a well-known mechanism. We explored the benefits of a major short chain fatty acid, butyrate on experimental ulcerative colitis in rats. The ulcerative colitis was induced by intrarectal instillation of 10% acetic acid after or without prior administration of 50 or 150 mg/kg butyrate intraperitoneally or intrarectally, respectively, for three consecutive days prior to exposure to acetic acid. After 24 hours of exposure to acetic acid, rats were sacrificed, postmortem examination done, intestinal sections fixed, processed and stained for histopathology in a routine manner. Acetic acid induced infiltration of inflammatory cells, loss of epithelium, crypt damage, and loss of goblet cells in the colon. These changes were significantly suppressed following butyrate treatment. We conclude that butyrate reduces the severity of acetic acid induced ulcerative colitis lesions in rats. This protective potency could be, at least in part, one of the mechanisms by which butyrate imparts its benefits to ulcerative colitis patients. Tanzania Veterinary Journal Vol. 25 (1) 2008: pp. 1-12

Book ChapterThe contribution of intestinal epithelium to the innate immune system includes detect... more Book ChapterThe contribution of intestinal epithelium to the innate immune system includes detecting luminal microbes, transducing signals, and activating inflammatory mediator release by epithelial and other cells of the immune system like the antigen presenting cells. Microbial antigens are detected by cells of the innate immune system through their pattern recognition receptors (PRRs). The PRRs recognize microbe-associated molecular patterns and generate signals that activate transcription pathways like nuclear factor kappa B and mitogen activated protein kinases. This activation leads to production of inflammatory and growth mediators that drive the immune system to elicit tolerance or immune response designated at maintaining immune homeostasis. Key to this signaling is the gut microbiota. Intestinal epithelial cell sensing of optimally balanced microbiota favors immune homeostasis whereas sensing under disrupted microbiota impairs immune function and predisposes to disease. Un...

Proceeding of the 35 scientific conference of Tanzania veterinary Association, Vol. 35: 147-152A ... more Proceeding of the 35 scientific conference of Tanzania veterinary Association, Vol. 35: 147-152A 4-year-old East African black headed ewe was presented to Sokoine University of Agriculture Animal Hospital with a history of loss of body condition and respiratory distress. Clinical examination revealed poor body condition, severe leukopenia with neutrophilia and lymphopenia. Radiographic examination of the thorax revealed an elongated caudal mediastinal mass with soft tissue opacity dorsal to caudal vena cava and caudal to the carina. The ewe was humanely euthanised due to deteriorated body condition. At post-mortem examination the mass contained caseous creamy material with early laminated appearance surrounded by a whitish fibrous capsule suggestive of chronic abscessation of caudal mediastinal lymph node. Corynebacterium pseudotuberculosis was isolated on bacterial culture of pus sample. A diagnosis of an abscessed caudal mediastinal lymph node as a result of Corynebacterium pseudo...

Book ChapterThe digestive system, which extends from the mouth to the anus, is responsible for re... more Book ChapterThe digestive system, which extends from the mouth to the anus, is responsible for receiving food, breaking it down into nutrients (digestion), absorbing the nutrients into the bloodstream, and eliminating the undigestible parts of food from the body. It consists of the mouth, throat, esophagus, stomach, small intestine, large intestine, rectum, and the anus. In addition, the digestive system consists of accessory digestive glands namely the liver, exocrine pancreas, and the biliary system consisting of the gallbladder and the bile duct. Disorders of the gastrointestinal system can be divided into: 1. Upper gastrointestinal disorders which involve diseases of the oral cavity, esophagus, and the stomach. Disorders of the oral cavity include those in the mouth, parotid and other salivary glands, and the pharynx. 2. Intestinal disorders which include disorders of the small intestine, large intestine, those involving both small and large intestine, rectum, and the anus. Conditions affecting the small intestine include conditions like enteritis (duodenitis, jejunitis, ileitis), duodenal (peptic) ulcer, and malabsorption. Those affecting the large intestine include appendicitis, colitis, functional colonic disease (e.g. irritable bowel syndrome, intestinal pseudoobstruction), megacolon, and diverticular disease. Examples of conditions occurring in both large and small intestines are enterocolitis and Crohn’s disease. Conditions affecting the rectum and the anus include proctitis, rectal prolapsed, anorectal fistula/fissure, and hemorrhoids. 3. Accessory digestive gland disorders are disorders of the liver, exocrine pancreas, gallbladder and bile duct. Examples of conditions affecting the liver include disorders of the liver parenchyma such as acute viral hepatitis (hepatitis A,B,C,D,E), yellow fever, cirrhosis, haemochromatosis and tumors like hepatocellular carcinoma. The biliary system could suffer from cholecystitis, gallstones, and cholesterolosis whereas the exocrine pancreas may have developmental abnormalities, pancreatitis, and pancreatic insufficiency. Owing to the nature and location of the condition, symptoms and subsequent treatment and prevention vary significantly. In general terms, congenital disorders may need surgical correction while infectious cases need antimicrobial therapy following identification of specific causative agents. Most of the gastrointestinal disorders are treated symptomatically. In this case, therapy is instituted to correct effects of symptoms such as vomiting and diarrhea (antiemetics, oral rehydration salts, intravenous fluid infusion) or muscular disorders like esophageal spasms where long acting anticholinergics or calcium blockers such as nifedipine relief the symptoms. Thus use of antimicrobials, surgery, and symptomatic therapy are major approaches to treatment of gastrointestinal disorders. Apart from congenital and inherited disorders, many gastrointestinal conditions can be prevented by proper and safe nutrition as well as drinking of safe water. Some specific conditions, such as gastritis, gastric and duodenal ulcers, inflammatory bowel diseases, cirrhosis, liver failure, and pancreatitis may need very special attention for treatment. In this book chapter, current findings on research and medical practice on symptoms, treatment and prevention of specific gastrointestinal disorders will be described in detail

Book Chapter, Chapter 7According to hygiene hypothesis, diseases of the immune system are increas... more Book Chapter, Chapter 7According to hygiene hypothesis, diseases of the immune system are increasing with socio-economic and sanitary conditions. This is evidenced by high incidences of allergic and autoimmune diseases in Western countries than in developing countries. The underlying factor is disruption of normal microbiota and their associated beneficial effects on intestinal mucosal immunity. Thus the pathogeneses of these disorders appear to revolve around impaired ability of the intestinal microbiota to effectively modulate and thus balance the body immune responses. As a result the immune system reacts excessively to antigens that would otherwise be tolerated and thus results in allergic reactions. Alternatively, the immune system reacts to self-antigens to cause autoimmune diseases. Some of these disorders are characterized by persistent production of inflammatory mediators leading to chronic inflammation and tissue damage. Several reports have indicated that oral administration of excessive numbers of selected members of microbiota, so called probiotic bacteria, prevents, treats, and improves the conditions of patients with immune-mediated disorders like allergy, inflammatory bowel diseases, and type 1 diabetes mellitus. Current knowledge suggests that probiotic bacteria mediate their beneficial effects via modulation of the immune system to balance its responses and institute protection. Herein the knowledge of new research on the role of probiotic bacteria on the development of some of the immune mediated diseases is reviewed in order to provide an insight in the role of probiotics in health and disease

Tienda online donde Comprar Probiotic bacteria and enteric infections. Cytoprotection by probioti... more Tienda online donde Comprar Probiotic bacteria and enteric infections. Cytoprotection by probiotic bacteria al precio 152,99 € de J. Malago | J. Koninkx | R. Marinsek-Logar, tienda de Libros de Medicina, Libros de Medicina Familiar y Comunitaria/General - Medicina general

International Journal of Sciences: Basic and Applied Research, 2018

Cellular response to stress leads to production of heat shock proteins (Hsps) that are protective... more Cellular response to stress leads to production of heat shock proteins (Hsps) that are protective against various perturbations including stress, infection and inflammation. The liver is a victim to many body disturbances including intoxications and systemic diseases. Stemming on the ability of Hsps to protect an array of perturbations in various body systems, it is justifiable to explore their protective potency to the rat model of carbon tetrachloride (CTC)-induced hepatic toxicity. The current study therefore aimed at testing whether prior induction of Hsp90 could protect the liver against CTC. Rats were exposed to zinc sulphate (ZS) to induce Hsp90 then CTC for 8, 24, 48 or 72 hr. At the end of treatment, rats were sacrificed, autopsied, liver samples taken and fixed in formalin and routinely processed. Sectioned tissues were stained with hematoxylin and eosin or anti-Hsp90 monoclonal antibodies to assess morphological changes and Hsp90 expression respectively. CTC induced damag...

The large number of microbials in the intestine that overrides the total human cells by ten folds... more The large number of microbials in the intestine that overrides the total human cells by ten folds alludes to significant contribution of the microbiota to human health. This is vivid in enteric and some systemic diseases emanating from disruption of the microbiota. The microbiota influences the development and functioning of both, innate and acquired immune systems for gut health. The effect of microbiota spills throughout the various components of the gut immune systems from “primitive” non specific pattern recognition receptors (PRR) to most specific adaptive T cell responses. To induce immune responses, commensal microbes are recognized by PRRs, which in turn regulate mucosal innate immunity and inflammatory responses. PRRs detect microbe-associated molecular patterns (MAMPs or "infectious non-self") or endogenous "danger signals" derived from stressed, damaged or infected tissue to stimulate the intestinal innate immunity that initiates adaptive immune responses. MAMPs include peptidoglycans, lipoproteins, lipopolysaccharides, teichoic acids, CpG DNA motif, double strand RNA and flagellin. In a balanced microbiota profile, PRR signaling ensures immune homeostasis and protects the host against enteral pathogens. Chapter one of this book will discuss the influence of the microbiota to PRR signaling during health and disease for intestinal immunity. Chapter two of the book focuses on a second level of innate immune system. This involves cells of the innate immune system that are responsible for driving non-specific innate immunity. They include natural killer cells, mast cells, eosinophils, basophils and the phagocytic cells including macrophages, neutrophils and dendritic cells. However, owing to the great commitment of macrophages and dendritic cells, a separate chapter for these two phagocytic cell types is allocated. Thus chapter two discusses the influence of microbiota on innate cells engendering intestinal immunity under health and disease. It concludes the innate immune system of the intestine. Macrophages and dendritic cells are professional antigen presenting cells. They sample antigens from the intestinal lumen, process, and present them to cells of the adaptive immune system. Despite of enormous types of enteral antigens ranging from harmful to beneficial, the antigen presenting cells are capable of efficiently discriminating them and driving respective responses to effector cells of the adaptive immune system. While dendritic cells are capable of priming T cell responses, macrophages do polarize the responses. As to how the microbiota influences the functioning of these cells, chapter three is devoted to discuss that phenomenon. The chapter links innate and adaptive intestinal immune systems since macrophages and dendritic cells lie in the interface between innate and adaptive immune systems. The acquired or adaptive immunity of the gut is split in humoral and cellular components. The humoral immune system is mainly geared by gut-associated lymphoid tissue (GALT) whose components include effector (i.e. epithelial lymphocytes and lamina propria) and inductive (i.e. mesenteric lymph nodes, Peyer’s patches, isolated lymphoid follicles, and cryptopatches) sites. It is interesting to note that microbiota influences GALT development and functioning during health and diseases. In germ free animals and those with disrupted microbita, GALT functioning is heavily compromised leading to diseases. Restoration of normal microbiotal profile to such individuals cures the disorders. Chapter four of this book will describe how the microbiota interacts with GALT and other components of the humoral immune system to maintain intestinal immunity under health and disease. The last chapter, chapter 5, focuses on the second part of the adaptive immune system which is cellular immune system. This system is dominated by several CD4 and CD8 lymphocytes that drive the cellular adaptive immune system. The main components are CD4+ cells which include T helper and regulatory T cells. Other T cells include cytotoxic T, memory, natural killer, and mucosa associated invariant T cells. While T helper cells drive most of the inflammatory responses, regulatory T cells downregulate these responses. As such, they are considered potential therapeutic agents of the future. Current knowledge indicates that the functioning of most, if not all, T cells is influenced by the microbiota. Chapter 5 is therefore devoted to discuss how the microbiota interacts with T cells during health and disease to foster intestinal immunity. In the past few years we have encountered mounting evidence showing that the microbiota plays essential role in regulating and maintaining host’s intestinal immunity. This is done through various ways including; regulation of mucin gene expression by goblet cells, modification of glycosylation of mucus to interfere with bacterial adhesion, colonization and invasion, induction of secretion of antimicrobial peptides by…

International Journal of Sciences: Basic and Applied Research, 2018

Heat shock response is rapidly induced to protect cells from irreversible injury by stabilizing c... more Heat shock response is rapidly induced to protect cells from irreversible injury by stabilizing cellular synthetic and metabolic activities. Particularly, the response differentially protects against stresses, infections and inflammations. While it could be time- and tissue-dependent, it is not established as to how it exhibits. This study explored the expression of heat shock protein (Hsp) 27, 70 and 90 in intestines, kidneys, livers and lungs of mice undergoing hyperthermia at 42 ° C for 1 hr and recovering for 1-72 hr. The expression of these Hsps was determined by immunohistochemical staining of formalin-fixed paraffin-embedded tissue sections. There was an increase in the expression of Hsp27, 70 and 90 that peaked at 6-12 hr and differentially declined at 48-72 hr. The peak expression was reached earlier in the lung and dropped sharply in the intestine while sustained for a longer time in the liver and kidney. At 72 hr only Hsp90 exhibited moderate expression in the lung and ki...

Tanzania Veterinary Journal, 2018

Macrophages, dendritic cells (DCs) and to less extent B cells are professional antigen presenting... more Macrophages, dendritic cells (DCs) and to less extent B cells are professional antigen presenting cells (APCs). They sample antigens from the intestinal lumen, process, and present them to cells of the adaptive immune system. While DCs are capable of priming T cell responses, macrophages do polarize the responses. The intestinal lumen contains diverse range of antigens from food proteins, microbiota, and pathogenic microbes that constantly challenge the immune system. While antigens from food proteins and microbiota are not harmful, those from pathogenic microbes are detrimental to the body. The immune system detects both types of antigens and drives immune responses geared at inducing tolerance or reaction to maintain immune homeostasis. Uptake of these antigens is done by the APCs. These cells present antigens to effector cells of the adaptive immune system which generate responses corresponding to particular antigen. The microbiota influences the nature and type of responses gene...

Health Care : Current Reviews, 2018

Despite the efforts to minimize malaria infection in Tanzania, its prevalence persists. To what f... more Despite the efforts to minimize malaria infection in Tanzania, its prevalence persists. To what factors is the persistence be attributed? Does people's lack of knowledge, impact negatively on their receptivity of malarial preventive and control strategies? This paper examines knowledge about control strategies of malaria, both curative and preventive, among local native of Lindi Urban district, in Tanzania, with the specific objectives to determine people's knowledge about malaria control strategies. Both qualitative and quantitative data were collected from 356 respondents. Focus group discussion were employed in eliciting qualitative information whereas a structured questionnaire was utilized to collect quantitative data. Both descriptive and inferential statistics were used in the analysis of these data. Descriptive analyses involved computation of frequency and percentages. Inferential measures were determined through Chi-square test. Knowledge of participants was significantly associated (P<0.05) with educational level, location of respondents, marital status and occupation. As such, knowledge about malaria control strategies in the study district was much different between respondents who had different socioeconomic factors. However, there was insignificant association (P>0.05) between malarial knowledge, sex, age of respondents and total number of members per household. Conclusively, this paper found that participants had information about malaria preventive strategies; they hardly had knowledge about the cause of malaria, importance of using mosquito nets consistently in protecting themselves from disease, and had no knowledge about how to integrate as well as implement various malaria preventative measures. Additionally, some misconceptions among respondents were discerned regarding cure of malaria, symptoms, and the effectiveness of bed nets.

Journal of Zhejiang University. Science. B, 2015

Intrarectal infusion of butyrate improves colorectal disorders including ulcerative colitis (UC).... more Intrarectal infusion of butyrate improves colorectal disorders including ulcerative colitis (UC). However, it is not established whether systemically administered butyrate benefits such patients. The current study aimed at exploring and comparing the potential of intraperitoneally, intrarectally, and orally administered butyrate against acetic acid (AA)-induced UC in rats. Intrarectal administration of 2 ml of 50% AA was done after or without prior treatment of rats for 7 consecutive days with 100 mg/kg sodium butyrate (SB) intraperitoneally, intrarectally, or orally. Rats were sacrificed after 48 h of AA-treatment. Subsequently, colon sections were processed routinely for histopathological examination. We clinically observed diarrhea, loose stools, and hemoccult-positive stools, and histologically, epithelial loss and ulceration, crypt damage, goblet cell depletion, hemorrhage, and mucosal infiltration of inflammatory cells. The changes were significantly reduced by intraperitoneal...

Beneficial microbes, 2010

Invasion of the gut by pathogenic Salmonella leads to production of IL-8 that initiates inflammat... more Invasion of the gut by pathogenic Salmonella leads to production of IL-8 that initiates inflammatory reactions to combat the bacterium. However, its persistent production causes tissue damage and interventions that suppress IL-8 production prevent tissue damage. We hypothesised that probiotics could mediate their benefits via inhibition of IL-8 synthesis. Caco-2 cells were infected with probiotic Bifidobacterium infantis W52, Lactobacillus casei W56, Lactococcus lactis W58, Lactobacillus acidophilus W70, Bifidobacterium bifidum W23, or Lactobacillus salivarius W24 or pathogenic Salmonella enterica serovar Enteritidis 857 at 0, 0.2, 1, 2, 10, 20, 100 or 200 bacterial cells/Caco-2 cell for 1 hour. Cells were also exposed to a combination of one probiotic bacterium (200 bacterial cells/Caco-2 cell) and the graded numbers of Salmonella as either co-incubation (1 hour) or pre-incubation of the probiotic bacterium (1 hour) followed by Salmonella (1 hour). The cells recovered for 2 or 24 h...

Journal of Zhejiang University. Science. B, 2008

The histopathological features and the associated clinical findings of ulcerative colitis (UC) ar... more The histopathological features and the associated clinical findings of ulcerative colitis (UC) are due to persistent inflammatory response in the colon mucosa. Interventions that suppress this response benefit UC patients. We tested whether sodium arsenite (SA) benefits rats with dextran sulfate sodium (DSS)-colitis. The DSS-colitis was induced by 5% DSS in drinking water. SA (10 mg/kg; intraperitoneally) was given 8 h before DSS treatment and then every 48 h for 3 cycles of 7, 14 or 21 d. At the end of each cycle rats were sacrificed and colon sections processed for histological examination. DSS induced diarrhea, loose stools, hemoccult positive stools, gross bleeding, loss of body weight, loss of epithelium, crypt damage, depletion of goblet cells and infiltration of inflammatory cells. The severity of these changes increased in the order of Cycles 1, 2 and 3. Treatment of rats with SA significantly reduced this severity and improved the weight gain.

Tanzania Veterinary Journal, 2009

Theileriosis, in particular East Coast Fever, remains to be a challenge to herdsmen in Eastern, C... more Theileriosis, in particular East Coast Fever, remains to be a challenge to herdsmen in Eastern, Central and Southern Africa. Its treatment cost is unbearable to majority of rural poor keepers who have subsequently opted for alternatives. Some herdsmen have developed a practice of heat application to parotid and prescapular lymph nodes of cattle with theileriosis to treat the disorder. The approach has been beneficial from time immemorial. Although the actual mechanism of this approach remains enigmatic, it might be linked with the protective role of heat shock response observed in several conditions. This prompts for closer look into the possible protective mechanisms of heat shock response against theileriosis. By gaining insight into how the heat shock response protects hosts against infections and its potential to protect cattle against theileriosis, therapeutic approaches to combat theileriosis could be improved. This work therefore, explores the cellular events triggered by Theileria parasite in the host cell as well as the possible sites at which heat shock response interferes to prevent establishment of the parasite and development of clinical theileriosis. It is concluded that the heat shock response is beneficial to animals against theileriosis. This concept can serve as a prelude to new therapeutic approaches against theileriosis. Keywords : Theileriosis, T. parva, NF-κB, Hsps, apoptosis Tanzania Vet Journal Vol. 25 (2) 2008: pp. 75-87

Tanzania Veterinary Journal, 2009

The local chicken has profound potential for upgrading through cross breeding with improved comme... more The local chicken has profound potential for upgrading through cross breeding with improved commercial birds to increase meat and egg production. This study aimed at evaluating egg traits, hatchability, fertility, chick hatch weight, and chick survivability of commercial Rhode Island Red (RIR), local, and crossbred chickens. A total of 6752 local chicken eggs were collected to obtain breeding stock and to study egg traits. RIR breeding stock was obtained from raising 250 (50 males, 200 females) while crossbred chickens were obtained by crossing RIR layer cocks to local hens and vice versa. A total of 1382, 1523, and 1476 local, RIR, and crossbred chicken eggs respectively were assessed for egg weight, length, breadth, and volume as well as chick hatch weight. Fertility and hatchability were assessed in 3675 local chicken eggs and 3350 eggs from RIR and crossbred chicken each. There was no significant difference (p < 0.05) in egg traits and chick hatch weight between RIR and crossbred chickens but these birds had significantly higher egg weight, egg length, egg breadth, egg volume, and chick hatch weight than local chickens. There were significant (p < 0.0001) positive relationships between egg volume and egg weight, chick hatch weight and egg weight, and chick hatch weight and egg volume for all chickens. Fertility was 92.0±4.14, 91.1±4.42, and 94.5±2.21 for local, RIR, and crossbred chickens respectively. Hatchability varied significantly at p<0.05 (80.6±1.43 in crossbred, 64.0±2.16 in RIR, and 52.2±2.54 in local chickens). Survivability of local chicks was superior by 50% over RIR and crossbred chicks. It is concluded that cross breeding local chickens to RIR produces a superior breed to local ecotype in terms of egg traits, hatchability and survivability. Such superiority can be exploited to upgrade the genetic potential of local ecotype and thus improve poultry production.

Probiotic Bacteria and Enteric Infections, 2011

The gut microbiota is part and parcel of the innate immunity that protects the host against enter... more The gut microbiota is part and parcel of the innate immunity that protects the host against enteric pathogens. Soon after birth, its composition starts to establish in the infant depending upon the method of delivery and the environment. Factors like nutrition, antimicrobial usage, age, changes in intestinal motility, behavioural changes, and several others, subsequently affect the individual’s microbiotal composition throughout

Beneficial Microbes, 2015

The large number of intestinal microorganisms, which exceeds the total number of human cells by t... more The large number of intestinal microorganisms, which exceeds the total number of human cells by ten folds, alludes to a significant contribution to human health. This is vivid in enteric and some systemic diseases emanating from disruption of the microbiota. As life style keeps shifting towards disruption of the microbiota in most societies worldwide, interest in the contribution of the microbiota to gut health has grown enormously. Many studies have been conducted to elucidate the exact contribution of the microbiota to human health. The knowledge gained from these studies indicates that the microbiota interacts with the intestinal milieu to maintain gut health. In this review, the crosstalk of microbiota with the intestinal physicochemical barrier pivotal to the gut innate immunity is highlighted. In particular, the review focuses on the role of the microbiota on competitive exclusion of pathogens, intestinal pH, epithelial mechanical barrier integrity, apical actin cytoskeleton, ...

Probiotic Bacteria and Enteric Infections, 2011

... Cytoprotection Joshua J. Malago and Jos FJG Koninkx JJ Malago (???) Department of Veterinary ... more ... Cytoprotection Joshua J. Malago and Jos FJG Koninkx JJ Malago (???) Department of Veterinary Pathology, Faculty of Veterinary Medicine, Sokoine University of Agriculture, PO Box 3203, Chuo Kikuu, Morogoro, Tanzania e-mail: malagojj@yahoo.com Page 2. 290 ...

Tanzania Veterinary Journal, 2008

Short chain fatty acids are increasingly used as food additives due to the health benefits they h... more Short chain fatty acids are increasingly used as food additives due to the health benefits they have. Recently, they have been implicated in protecting patients against intestinal disorders but without a well-known mechanism. We explored the benefits of a major short chain fatty acid, butyrate on experimental ulcerative colitis in rats. The ulcerative colitis was induced by intrarectal instillation of 10% acetic acid after or without prior administration of 50 or 150 mg/kg butyrate intraperitoneally or intrarectally, respectively, for three consecutive days prior to exposure to acetic acid. After 24 hours of exposure to acetic acid, rats were sacrificed, postmortem examination done, intestinal sections fixed, processed and stained for histopathology in a routine manner. Acetic acid induced infiltration of inflammatory cells, loss of epithelium, crypt damage, and loss of goblet cells in the colon. These changes were significantly suppressed following butyrate treatment. We conclude that butyrate reduces the severity of acetic acid induced ulcerative colitis lesions in rats. This protective potency could be, at least in part, one of the mechanisms by which butyrate imparts its benefits to ulcerative colitis patients. Tanzania Veterinary Journal Vol. 25 (1) 2008: pp. 1-12