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Papers by karen regina lemos

Pesquisa Veterinaria Brasileira, Jul 1, 1999

Antigenic characterization of Trypanosoma evansi using sera from experimentally and naturally inf... more Antigenic characterization of Trypanosoma evansi using sera from experimentally and naturally infected bovines, equines, dogs, and coatis Caracterização antigênica do Trypanosoma evansi usando soros de bovinos, equinos, cães e quatis experimentalmente e naturalmente infectados

Archives of Veterinary Science, 2020

Síndrome de asma severa equina é uma afecção respiratória de vias aéreas inferiores associada a d... more Síndrome de asma severa equina é uma afecção respiratória de vias aéreas inferiores associada a dispneia grave em repouso e intolerância ao exercício. Apresenta quadro clínico e fisiopatológico muito semelhante à asma humana e, dentro das alterações observadas, o remodelamento da matriz extracelular (MEC) das vias aéreas é um ponto crítico. A fibronectina é uma glicoproteína adesiva que participa do processo de remodelamento e está presente transitoriamente durante o desenvolvimento ou em processos regenerativos da MEC. Este trabalho buscou analisar a distribuição e quantificá-la através de imunohistoquímica. As amostras avaliadas eram lâminas com cortes de 5 µm de espessura de tecido pulmonar oriundo de sete equinos incluídos no grupo ASMA/ORVA (idade superior a 7 anos, expostos a antígenos de poeira de feno, em fase clínica de exacerbação, anamnese e avaliação clínica com quadro de esforço expiratório e dispneia em repouso, avaliação do lavado broncoalveolar com neutrofilia maior ...

Equine Veterinary Journal, 2018

SummaryBackgroundCorticosteroids are the most potent drugs for the control of severe equine asthm... more SummaryBackgroundCorticosteroids are the most potent drugs for the control of severe equine asthma, but adverse effects limit their chronic systemic administration. Inhaled medications allow for drug delivery directly into the airways, reducing the harmful effects of these drugs.ObjectivesTo evaluate the efficacy of inhaled budesonide specifically formulated for the equine use and administered by a novel inhalation device in horses with severe asthma.Study designExperimental studies in horses with naturally occurring asthma with cross‐over, randomised, blinded experimental designs.MethodsIn Study 1, budesonide (1800 μg twice daily) administered using a novel Respimat® based inhaler was compared to i.v. dexamethasone (0.04 mg/kg). In Study 2, 3 doses of budesonide (450, 900, and 1800 μg) were compared to oral dexamethasone (0.066 mg/kg). Lung function, bronchoalveolar fluid cytology (Study 1), CBC, serum chemistry, and serum cortisol and adrenocorticotropic hormone (ACTH) values were...

Revista Acadêmica: Ciência Animal, 2016

Hydrocolloid dressing is a bioactive product used to improve the healing process of large open wo... more Hydrocolloid dressing is a bioactive product used to improve the healing process of large open wounds. InMarch 2011, a horse was evaluated at the Veterinary Medical Teaching Hospital- UNICENTRO, Guarapuava,Brazil. The animal presented with epistaxis and inspiratory dyspnoea associated with fracture of the orbitalpart of the frontal bone with a comminuted fracture of the zygomatic process and bone loss of the articulartubercle of the temporal bone reaching the zygomatic process, tooth fracture and a partial laceration of theleft cheek with avulsion of the eyeball. After the reconstructive facial surgery and enucleation we used thehydrocolloid dressing during the repair phase. It helped re-establish the epithelial layer, avoided excessivegranulation tissue formation and decreased the healing time. Seven days after surgery and the use ofbiological membrane we verified the production of intense and controlled granulation tissue, beyond thatthe membrane was a viable and low cost alternat...

A32. HUMAN AND ANIMAL STUDIES OF CHRONIC DISEASES THAT AFFECT THE LUNG, 2011

American journal of physiology. Lung cellular and molecular physiology, 2014

The consequences on lung function and inflammation of alterations in the extracellular matrix aff... more The consequences on lung function and inflammation of alterations in the extracellular matrix affecting the peripheral airway wall in asthma are largely unknown. We hypothesized that remodeling of collagen and elastic fibers in the peripheral airway wall leads to airway obstruction and contributes to neutrophilic airway inflammation. Animals used were six heaves-affected horses and five controls. Large peripheral lung biopsies were obtained from horses with heaves in clinical remission (Baseline) and during disease exacerbation and from age-matched controls. The area of collagen and elastic fiber content in the lamina propria was measured by histological staining techniques and corrected for airway size. Collagen type 1 and type 3 content was further assessed from additional horses after postmortem lung samples by immunohistochemistry. The collagen breakdown products proline-glycine-proline (PGP) and N-acetylated-PGP (N-α-PGP) were also measured in bronchoalveolar lavage fluids (BAL...

ABSTRACT The goals of this study were to evaluate if hemoglobin played a role as adjuvant in expe... more ABSTRACT The goals of this study were to evaluate if hemoglobin played a role as adjuvant in experimental peritonitis in horses and could cause clinical and haematological alterations that could be used for diagnosis and prognosis of cases of peritonitis. Fifteen adult horses were randomly divided into 5 equal groups, which were injected intraperitoneally with the following suspension: GI: 1x109 colony-forming units (CFU) of E. coli diluted in 500 mL of 0.9% saline solution plus 5 g of hemoglobin; GII: 1x109 CFU of B. fragilis diluted in 500 mL of 0.9% saline plus 5 g of hemoglobin; GIII: 1x109 CFU of E. coli in combination with 1x109 CFU of B. fragilis diluted in 500 ml of 0.9% of saline plus 5 g of hemoglobin; GIV: 500 mL of 0.9% saline plus 5 g of hemoglobin and GV: 500 mL of 0.9% saline. Leukopenia with neutropenia was observed in GI and GIII and a significant increase in plasma fibrinogen concentration occurred in horses of GI. There was a significant increase in total nucleated cell count in peritoneal fluid in horses of GI, GII, GIII and GIV. Fever, tachycardia, tachypnea, abdominal wall sensibility and tension, diarrhoea, colic, and decreased borborygmi sounds were the most frequent clinical signs observed in horses of GI, GII, GIII and GIV. In conclusion, hemoglobin was able to cause chemical peritonitis in horses, it had an adjuvant effect when associated to E. coli in experimental peritonitis in horses potentiating pathogenic effects of E. coli, but was not lethal to horses.

Revista Brasileira de Parasitologia Veterinária, 2010

Revista do Instituto de Medicina Tropical de São Paulo, 2008

This study aimed to characterize astrocytic and microglial response in the central nervous system... more This study aimed to characterize astrocytic and microglial response in the central nervous system (CNS) of equines experimentally infected with T. evansi. The experimental group comprised males and females with various degrees of crossbreeding, ages between four and seven years. The animals were inoculated intravenously with 10(6) trypomastigotes of T. evansi originally isolated from a naturally infected dog. All equines inoculated with T. evansi were observed until they presented symptoms of CNS disturbance, characterized by motor incoordination of the pelvic limbs, which occurred 67 days after inoculation (DAI) and 124 DAI. The animals in the control group did not present any clinical symptom and were observed up to the 125th DAI. For this purpose the HE histochemical stain and the avidin biotin peroxidase method was used. Lesions in the CNS of experimentally infected horses were those of a wide spread non suppurative meningoencephalomyelitis.The severity of lesions varied in diff...

Revista Brasileira de Parasitologia Veterinária, 2014

The purpose of this study was to estimate the prevalence of Theileria equi in horses from central... more The purpose of this study was to estimate the prevalence of Theileria equi in horses from central western region of Paraná state, Brazil. The presence of antibodies IgG against T. equi was determined in serum samples obtained from 400 team roping horses of the district of Guarapuava by the enzyme-linked immunosorbent assay (ELISA). Results showed that 242 (61%) animals were positive which demonstrates that equine piroplasmosis is widespread and therefore it might be a contributing factor for the irregular performance among athletes horses in the region studied. No association regarding age and sex were observed (p>0.05). To our knowledge, this is the first report describing a serological survey on equine piroplasmosis in the state of Paraná, Brazil.

Journal of Veterinary Internal Medicine, 2012

BackgroundSystemic inflammation in horses with heaves is poorly characterized.ObjectivesTo assess... more BackgroundSystemic inflammation in horses with heaves is poorly characterized.ObjectivesTo assess acute phase proteins (APP) and inflammatory cytokine profiles in serum of healthy horses and horses with heaves.AnimalsSix healthy horses and 6 heaves‐affected horses belonging to the University of Montreal.MethodsProspective, observational study. Healthy and heaves‐affected control horses were exposed to a 30‐day natural challenge with hay and straw to induce clinical exacerbation of heaves. Serum samples were obtained by venipuncture before (T0) as well as after 7 (T7) and 30 days (T30) of stabling. Serum APP (haptoglobin, serum amyloid A protein [SAA] and C‐reactive protein [CRP]) and cytokines (IL‐2, IL‐4, IFN‐α, IL‐10, IFN‐γ, and CCL‐2) were measured using singleplex or multiplex ELISA.ResultsSerum haptoglobin concentrations were significantly higher in heaves‐affected horses at all time points with no overlap with those of healthy controls. They were also significantly increased b...

Brain Research, 1998

ABSTRACT We examined by immunohistochemistry the expression of glial fibrillary acidic protein (G... more ABSTRACT We examined by immunohistochemistry the expression of glial fibrillary acidic protein (GFAP) in enteric ganglia of the chick embryo, using a polyclonal antibody. The morphology of enteric ganglion cells was examined by electron microscopy. Faint GFAP immunoreactivity was detected in ganglion cells and cell processes from around day 7 in ovo. Later in development the intensity of the immunofluorescence increased and it became more evident that immunoreactive small ganglion cells (interpreted as primitive glial cells), and their processes, surrounded larger negative cell profiles (interpreted as primitive neuronal cells); GFAP immunofluorescence was also evident in intramuscular and mucosal nerve trunks. In colocalization experiments, GFAP immunoreactivity was detected in a proportion of HNK-1/N-CAM immunoreactive ganglion cells, in both the myenteric and submucosal plexus. In addition, we observed GFAP immunoreactive nerves in wholemount preparations of chick gut from as early as day 4.5 in ovo. In the ganglionated nerve of Remak, GFAP immunoreactive satellite and Schwann cells were in evidence from day 5 of incubation. Neuronal markers, such as neurofilament, have been detected very early in development in neural crest cell populations in chick enteric ganglia. In contrast, the expression of markers of the glial phenotype has previously been observed only in the late stages of embryonic development. From our experiments, we conclude that neuronal and glial phenotypes are immunohistochemically distinct from as early as day 4.5 of incubation, even if by ultrastructural criteria glial cells are clearly distinguishable from neurons only after day 16 in ovo.

Archives of Environmental Contamination and Toxicology, 2009

This study was carried out to assess the influence of di(2-ethylhexyl)phthalate (DEHP) alone or a... more This study was carried out to assess the influence of di(2-ethylhexyl)phthalate (DEHP) alone or associated with antioxidants on the male reproductive system in newborn rats, emphasizing the implications of oxidative stress and hormonal balance during prenatal and early postnatal periods. Wistar females were exposed by oral route to DEHP alone or associated with antioxidants from gestational day 7 to lactational day 2 according to the following treatment regimens: (C) vehicle control (canola oil + 1% Tween-80); (V) vitamin C (200 mg/kg) + canola oil; (R) resveratrol (10 mg/kg) + canola oil; (D) DEHP (500 mg/kg) + 1% Tween-80; (DV) DEHP (500 mg/kg) + vitamin C (200 mg/kg); and (DR) DEHP (500 mg/kg) + resveratrol (10 mg/kg). Two male pups per litter were randomly selected and necropsied on postnatal day 2. The brain and liver were removed and weighed and anogenital distance (AGD) was measured. Additionally, the testes were removed for assessment of intratesticular testosterone levels and histopathology; the liver was used to measure biomarkers of oxidative stress. Vitamin C and resveratrol alone did not affect the reproductive end points and did not induce oxidative stress. Exposure of dams to DEHP alone and associated with antioxidants resulted in hepatomegaly in offspring and significantly increased the incidence of multinucleated gonocytes in seminiferous cords. Testosterone and AGD presented a trend to decrease in DEHP-exposed groups. Catalase activity increased only in groups exposed to DEHP associated with antioxidants, although GST (gluthatione-S-transferase) activity decreased in all DEHP-exposed groups. The levels of hydroperoxides increased only in group exposed to DEHP associated with vitamin C. These results indicate that the association of DEHP with antioxidants was unable to ameliorate DEHP-induced reproductive changes, and the coadministration of DEHP and these antioxidants might even contribute to an overall increase in oxidative stress.

Ciência Rural, 2007

A 10-year-old Mangalarga gelding with rhabditiform nematode infection in the brain is described. ... more A 10-year-old Mangalarga gelding with rhabditiform nematode infection in the brain is described. Clinical signs were limited to circling and right side paralysis. Histological examination of the brain revealed marked gliosis and discreet edema. The perivascular mononuclear inflammatory infiltrate was composed of few layers of lymphocytes, plasmocytes and macrophages and rare eosinophils. The presence of rhabditiform nematodes was associated with the infiltrate. Areas of malacia associated with the parasites and parasite tracks with axonal spheroids were also seen close to the vessels and to the etiological agent and were more evident in the white matter. In the meninges there was moderate inflammatory infiltrate associated with perivascular parasites. The identification of the nematode was based on the histological examination of the cerebral fragments.