Medical Microbiology Research Papers - Academia.edu (original) (raw)

Cysts of the mesentery are among surgical rarities and of varied aetiology with variable presentations and this has surgical implications in the pediatric age group. They may be derived from the gastrointestinal tract, the genitourinary... more

Cysts of the mesentery are among surgical rarities and of varied aetiology with variable presentations and this has surgical implications in the pediatric age group. They may be derived from the gastrointestinal tract, the genitourinary system, previous inflammation (pseudocysts) or malignant cystic tumours, but the commonest cause is generally considered to be a congenital lymphatic cyst. The clinical presentation is not characteristic and in addition, the preoperative imaging although suggestive is not diagnostic. In most cases, the diagnosis is confirmed after surgical exploration and removal of the cyst. A case report of a baby aged 6 months is being reported. Hope that this information will reinforce the diagnostic and treatment strategy.

ABSTRACTEpidemiological data on hepatitis delta virus (HDV) infection in Belgium are lacking. A multicenter questionnaire‐based registry on HDV infection was collated between March 1, 2008 and February 28, 2009. It consisted of patients... more

ABSTRACTEpidemiological data on hepatitis delta virus (HDV) infection in Belgium are lacking. A multicenter questionnaire‐based registry on HDV infection was collated between March 1, 2008 and February 28, 2009. It consisted of patients coinfected with hepatitis B virus (HBV) and HDV. The data samples were compared to those of a concurrent registry on HBV infection. Prospective data of patients with HBV–HDV coinfection were collected. Active HBV replication is defined as HBeAg positivity or HBV DNA > 2,000 IU/ml. Forty‐four patients from 15 centers were registered. A comparison of 29 patients infected with HDV (registered in the concurrent HBV registry) was made against 785 HBV mono‐infected patients. The seroprevalence of patients coinfected with HBV and HDV in Belgium is reported to be 3.7% (29/785), consisting solely of the HBV–HDV coinfected patients in the HBV registry. This rises to 5.5% (44/800) if all patients infected with HDV from the two registries combined are include...

Gastro-intestinal nematodes, especially Haemonchus contortus, are widespread pathogenic parasites of small ruminants. Studying their spatial genetic structure is as important as studying host genetic structure to fully understand... more

Gastro-intestinal nematodes, especially Haemonchus contortus, are widespread pathogenic parasites of small ruminants. Studying their spatial genetic structure is as important as studying host genetic structure to fully understand host-parasite interactions and transmission patterns. For parasites having a simple life cycle (e.g., monoxenous parasites), gene flow and spatial genetic structure are expected to strongly rely on the socio-spatial behavior of their hosts. Based on five microsatellite loci, we tested this hypothesis for H. contortus sampled in a wild Mediterranean mouflon population (Ovis gmelini musimon × Ovis sp.) in which species- and environment-related characteristics have been found to generate socio-spatial units. We nevertheless found that their parasites had no spatial genetic structure, suggesting that mouflon behavior was not enough to limit parasite dispersal in this study area and/or that other ecological and biological factors were involved in this process, f...

Background/Aims: Inflammasomes are multimolecular complexes that regulate caspase-1. They act as sensors for endogenous and exogenous signals, and mediate the processing of pro-IL-1β into its secreted, biologically active form. The NLRP3... more

Background/Aims: Inflammasomes are multimolecular complexes that regulate caspase-1. They act as sensors for endogenous and exogenous signals, and mediate the processing of pro-IL-1β into its secreted, biologically active form. The NLRP3 inflammasome and IL-1β are particularly interesting because they are required for efficient control of viral infections. Indeed, HIV-1 induces expression of NLRP3 and IL-1β in healthy controls, but not in HIV-1-infected patients. Here we evaluate whether HIV-1 can induce activation of the NLRP3 inflammasome. Methods: Human primary monocyte-derived macrophages were infected with HIV-1 in the absence or presence of classical NLRP3 inflammasome activators, and IL-1β release was assessed by ELISA. Results: HIV-1 initiates the priming signal for NLRP3 inflammasome activation through the NF-κB-associated pathway in human primary monocyte-derived macrophages. Furthermore, priming of NLRP3 activation in response to HIV-1 was independent of the viral envelop...

Three slow-growing rhizobial strains (WYCCWR 12678, WYCCWR 12774 and WYCCWR 13023T) isolated from effective nodules of Arachis hypogaea L. (cultivated peanut) sampled in Zhengyang County, Henan Province, central China were characterized... more

Three slow-growing rhizobial strains (WYCCWR 12678, WYCCWR 12774 and WYCCWR 13023T) isolated from effective nodules of Arachis hypogaea L. (cultivated peanut) sampled in Zhengyang County, Henan Province, central China were characterized using a polyphasic approach. The three strains were assigned to the genus Bradyrhizobium based on phylogenetic analysis of their 16S rRNA sequences. Phylogenetic analysis based on their concatenated recA-glnII-gyrB-dnaK-rpoB gene sequences placed the strains into a distinct lineage. Whole-genome average nucleotide identity (ANI) values between WYCCWR 13023T and WYCCWR 12774 and WYCCWR 12678 were 99.43 and 99.31% respectively. ANI values between WYCCWR 13023T and the most closely related strains were all below 93 %. The digital DNA–DNA hybridization (dDDH) values between WYCCWR 13023T and ‘ B. guangzhouense ’ CCBAU 51670T, B. manausense BR 3351T and B. guangdongense CCBAU 51649T, the three most closely related type strains, were 50.40, 43.50 and 39.20...

Tryptamine, a tryptophan-derived monoamine similar to 5-hydroxytryptamine (5-HT), is produced by gut bacteria and is abundant in human and rodent feces. However, the physiologic effect of tryptamine in the gastrointestinal (GI) tract... more

Tryptamine, a tryptophan-derived monoamine similar to 5-hydroxytryptamine (5-HT), is produced by gut bacteria and is abundant in human and rodent feces. However, the physiologic effect of tryptamine in the gastrointestinal (GI) tract remains unknown. Here, we show that the biological effects of tryptamine are mediated through the 5-HT receptor (5-HTR), a G-protein-coupled receptor (GPCR) uniquely expressed in the colonic epithelium. Tryptamine increases both ionic flux across the colonic epithelium and fluid secretion in colonoids from germ-free (GF) and humanized (ex-GF colonized with human stool) mice, consistent with increased intestinal secretion. The secretory effect of tryptamine is dependent on 5-HTR activation and is blocked by 5-HTR antagonist and absent in 5-HTR mice. GF mice colonized by Bacteroides thetaiotaomicron engineered to produce tryptamine exhibit accelerated GI transit. Our study demonstrates an aspect of host physiology under control of a bacterial metabolite t...

Indigenous Cr(VI) reducing bacterial strains Pseudomonas aeruginosa Rb-1 and Ochrobactrum intermedium Rb-2 were evaluated for EPS production under Cr(VI) challenged and free conditions. Strain Rb-2 was more efficient in total EPS... more

Indigenous Cr(VI) reducing bacterial strains Pseudomonas aeruginosa Rb-1 and Ochrobactrum intermedium Rb-2 were evaluated for EPS production under Cr(VI) challenged and free conditions. Strain Rb-2 was more efficient in total EPS production (13.63 mg g(-1) ) than Rb-1 (4.15 mg g(-1) ) under Cr(VI) stress. Thick covering of capsular material around the cells of both bacterial strains was detected by electron microscopy. Transmission electron micrographs showed the appearance of pilli like structures under chromium stress by two bacteria suggested the possible involvement of this in exchange of hereditary material to increase their chances of survival under stress conditions. FTIR study showed involvement of sulphonate and hydroxyl groups in the binding with Cr(VI) ions. Solid-state (13) C NMR spectra revealed that EPS produced by both strains exhibited structural similarity with the glucan. The partial psl gene sequences of Rb-1 and Rb-2 showed homology with psl gene of Pseudomonas a...

Objectives To analyse the possible relationship between consumption of old and new MRSA-active antibiotics and burden of MRSA in acute care hospitals in Catalonia during the period 2007–12. Methods Fifty-four hospitals participating in... more

Objectives To analyse the possible relationship between consumption of old and new MRSA-active antibiotics and burden of MRSA in acute care hospitals in Catalonia during the period 2007–12. Methods Fifty-four hospitals participating in the VINCat Programme were included. Proportion of MRSA (resistant isolates of Staphylococcus aureus per 100 isolates of S. aureus tested), incidence of new cases of infection [new cases of MRSA per 1000 occupied bed-days (OBD)] and incidence of cases of bacteraemia (MRSA bacteraemia cases per 1000 OBD) were determined to estimate the annual MRSA burden. Antibiotic consumption was calculated in DDD/100 OBD. Cost was expressed in euros/100 OBD. Results MRSA rates remained stable over the study period, with the proportion of MRSA ranging from 20% to 22.82% in 2007 and 2012, respectively (P = 0.864). Consumption of old MRSA-active antibiotics (vancomycin and teicoplanin) did not change significantly, with values from 1.51 to 2.07 DDD/100 OBD (P = 0.693). ...

Due to the ever-increasing rise of antimicrobial resistant (AMR) bacteria, the development of alternative antimicrobial agents is a global priority. The antimicrobial activity of ionic gold was explored against four Pseudomonas aeruginosa... more

Due to the ever-increasing rise of antimicrobial resistant (AMR) bacteria, the development of alternative antimicrobial agents is a global priority. The antimicrobial activity of ionic gold was explored against four Pseudomonas aeruginosa strains with different AMR profiles in order to determine the antimicrobial activity of ionic gold and elucidate the mechanisms of action. Disc diffusion assays (zone of inhibition: ZoI) coupled with minimum inhibitory/bactericidal concentrations (MIC/MBC) were conducted to determine the antimicrobial efficacy of ionic gold. Scanning electron microscopy (SEM) was used to visualise morphological changes to the bacterial cell ultrastructure. Strains with increased AMR were slower to grow which is likely a fitness cost due to the enhanced AMR activity. Although greater concentrations of ionic gold were required to promote antimicrobial activity, ionic gold demonstrated similar antimicrobial values against all strains tested. Lowry assay results indica...

BackgroundPlasmodium falciparumcauses the majority of malaria cases worldwide and children in sub-Saharan Africa are the most vulnerable group affected. Non-sterile clinical immunity that protects from symptoms develops slowly and is... more

BackgroundPlasmodium falciparumcauses the majority of malaria cases worldwide and children in sub-Saharan Africa are the most vulnerable group affected. Non-sterile clinical immunity that protects from symptoms develops slowly and is relatively short-lived. Moreover, current malaria vaccine candidates fail to induce durable high-level protection in endemic settings, possibly due to the immunomodulatory effects of the malaria parasite itself. Because dendritic cells play a crucial role in initiating immune responses, the aim of this study was to better understand the impact of cumulative malaria exposure as well as concurrentP. falciparuminfection on dendritic cell phenotype and function.MethodsIn this cross-sectional study, the phenotype and function of dendritic cells freshly isolated from peripheral blood samples of Malian adults with a lifelong history of malaria exposure who were either uninfected (n = 27) or asymptomatically infected withP. falciparum(n = 8) was assessed. Addit...

The impressive decline in child mortality that occurred in Rwanda from 1996-2000 to 2006-2010 coincided with a period of rapid increase of malaria control interventions such as indoor residual spraying (IRS); insecticide-treated net (ITN)... more

The impressive decline in child mortality that occurred in Rwanda from 1996-2000 to 2006-2010 coincided with a period of rapid increase of malaria control interventions such as indoor residual spraying (IRS); insecticide-treated net (ITN) distribution and use, and improved malaria case management. The impact of these interventions was examined through ecological correlation analysis, and robust decomposition analysis of contextual factors on all-cause child mortality. Child mortality fell 61% during the evaluation period and prevalence of severe anemia in children 6-23 months declined 71% between 2005 and 2010. These changes in malaria morbidity and mortality occurred concurrently with a substantial increase in vector control activities. ITN use increased among children under five, from 4% to 70%. The IRS program began in 2007 and covered 1.3 million people in the highest burden districts by 2010. At the same time, diagnosis and treatment with an effective antimalarial expanded nati...

This review article provides information on the biological activities of chalcone whether natural or synthetics derivatives. Chalcone (1,3diaryl-2-propen-1-ones) derivatives are widely found naturally (pteridophytes to multicellular... more

This review article provides information on the biological activities of chalcone whether natural or synthetics derivatives. Chalcone (1,3diaryl-2-propen-1-ones) derivatives are widely found naturally (pteridophytes to multicellular organism). Chemically it consist of open-chain flavonoids in which the two aromatic rings are joined by a three-carbon α,β-unsaturated carbonyl system. Chalcones have been reported to possess many pharmacological activities, including anti-inflammatory, antimicrobial, antifungal, antiviral antioxidant, hepato-protective, anti-cancer activities and also have been reported to manage cardiovascular system disorders. Chalcones are secondary metabolites found in plants. Some natural flavonoids also help in hostility oxidative stress and play vital role as growth regulators, chalcones may exist in cis or trans form and trans form is more favorable. Some chalcones are isolated naturally from different plants, and have been approved for clinical trials in the tr...

The article claims based on Russian studies that cancer is caused by crystallin formations in the spaces between the cells, which disconnect the cells. In a cut wound, the disconnected cells start to multiply fast to heal the wound fast... more

The article claims based on Russian studies that cancer is caused by crystallin formations in the spaces between the cells, which disconnect the cells. In a cut wound, the disconnected cells start to multiply fast to heal the wound fast and the healing regrowth is ruled by the current of regrow, which starts at the cut. In a cancerous tissue, the cells (disconnected by the crystallin formations) multiply senselessly because there is no current of regrowth to tell them where to go. Alzheimer disease is inability to memorize. It is caused by crystal-like formations in the space between the cells, called amyloid plaques, which make the communication of the neurons impossible. Since both diseases are caused by crystal formations in the space between the cells ruled by the lymph system, their cure or prevention would require flushing the lymph system. We all know that stress causes cancer, but we don’t know how. This article explains for the first time how stress causes cancer and Alzheimer disease.

Background : Soil-transmitted helminths are more prevalent in tropics and sub-tropics including Ethiopia. Despite their high prevalence, direct saline microscopy with its low sensitivity has been used as a diagnostic method in almost all... more

Background : Soil-transmitted helminths are more prevalent in tropics and sub-tropics including Ethiopia. Despite their high prevalence, direct saline microscopy with its low sensitivity has been used as a diagnostic method in almost all health facilities in Ethiopia. Alternative diagnostic methods which have higher sensitivity are not yet implemented. Therefore, this study aimed to compare and evaluate the performance of diagnostic methods for soil transmitted helminths against the “Gold” standard.Methods : A cross-sectional study among 520 school children was conducted from October to December, 2019 in Amhara National Regional State. The study participants were selected using systematic random sampling technique. Stool samples were processed via formol ether concentration, Kato-Katz, spontaneous tube sedimentation and agar plate culture techniques. Data was entered in to Epi-data version 3.1 and analysis was done using SPSS version 20.0. The sensitivity, specificity, and negative ...

Chickenpox, an infection of childhood with vesicular skin rash, is caused by varicella-zoster virus (VZV). Although the infection is rare in adults, it can cause serious complications Varicella pneumonia is the most encountered... more

Chickenpox, an infection of childhood with vesicular skin rash, is caused by varicella-zoster virus (VZV). Although the infection is rare in adults, it can cause serious complications Varicella pneumonia is the most encountered complication. In this report, a VZV pneumonia case in a previously healthy adult is presented. The patient was treated with early intravenous acyclovir and both clinical and radiographic recovery has been observed.

Background Diagnosis of tuberculosis (TB) remains problematic despite many new advanced diagnostic methods. A reliable and rapid diagnostic test, which could be performed in any standard pathology laboratory, would help to obtain... more

Background Diagnosis of tuberculosis (TB) remains problematic despite many new advanced diagnostic methods. A reliable and rapid diagnostic test, which could be performed in any standard pathology laboratory, would help to obtain definitive early diagnoses of TB. In the present study we describe a prospective evaluation for demonstrating Antigen (Ag) 85 complex in the sera from TB patients. Methods Indirect ELISA, employing monoclonal antibodies (mAb) against the purified Ag 85 complex, was used to demonstrate Ag 85 complex in sera from TB patients. Serum samples were obtained from 197 different groups of patients: confirmed TB {n = 24}, clinically diagnosed TB {n = 104}, disease controls {n = 49} and healthy controls {n = 20}. Receiver operating curve (ROC) was used to calculate the cut off value and comparison between TB and non-TB groups were done by the chi-square test. Results The indirect ELISA method, using an mAb against Ag 85 complex, yielded 82% sensitivity (95% confidence...