João Alison de Moraes Silveira

Bothropoides pauloensis venom effects on isolated perfused kidney and cultured renal tubular epithelial cells

Snake envenomation (Bothrops genus) is common in tropical countries and acute kidney injury is one of the complications observed in Bothrops snakebite with relevant morbidity and mortality. Here, we showed that Bothropoides pauloensis venom (BpV) decreased cell viability (IC50 of 7.5 μg/mL). Flow cytometry with annexin V and propidium iodide showed that cell death occurred predominantly by apoptosis and late apoptosis, through caspases 3 and 7 activation, mitochondrial membrane potential collapse and ROS overproduction. BpV reduced perfusion pressure, renal vascular resistance, urinary flow, glomerular filtration rate, percentage of sodium, chloride or potassium tubular transportation. These findings demonstrated that BpV cytotoxicity on renal epithelial cells might be responsible for the nephrotoxicity observed in isolated kidney.

Pulmonary mechanic and lung histology induced by Crotalus durissus cascavella snake venom

ABSTRACT This study have analyzed the pulmonary function in an experimental model of acute lung injury, induced by the Crotalus durissus cascavella venom (C. d. cascavella) (3.0 &mgr;g/kg ‐ i.p), in pulmonary mechanic and histology at 1 h, 3 h, 6 h, 12 h and 24 h after inoculation. The C. d. cascavella venom led to an increase in Newtonian Resistance (Symbol), Tissue Resistance (Symbol) and Tissue Elastance (Symbol) in all groups when compared to the control, particularly at 12 h and 24 h. The Histeresivity (Symbol) increased 6 h, 12 h and 24 h after inoculation. There was a decrease in Static Compliance (Symbol) at 6 h, 12 h and 24 h and inspiratory capacity (Symbol) at 3 h, 6 h, 12 h and 24 h. C. d. cascavella venom showed significant morphological changes such as atelectasis, emphysema, hemorrhage, polymorphonuclear inflammatory infiltrate, edema and congestion. After a challenge with methacholine (MCh), Symbol demonstrated significant changes at 6, 12 and 24 h. This venom caused mechanical and histopathological changes in the lung tissue; however, its mechanisms of action need further studies in order to better elucidate the morphofunctional lesions. Symbol. No caption available. Symbol. No caption available. Symbol. No caption available. Symbol. No caption available. Symbol. No caption available. Symbol. No caption available. Symbol. No caption available. HIGHLIGHTSC. d. cascavella venom increased Newtonian resistance, tissue resistance, tissue elastance and histeresivity in rat lungs.C. d. cascavella venom reduced static compliance and inspiratory capacity in rat lungs.C. d. cascavella venom induced morphological changes in the lung tissue.

Differences between renal effects of venom from two Bothrops jararaca populations from southeastern and southern Brazil

ABSTRACT Components from animal venoms may vary according to the snakes age, gender and region of origin. Recently, we performed a proteomic analysis of Bothrops jararaca venom from southern (BjSv) and southeastern (BjSEv) Brazil, showing differences in the venom composition, as well as its biological activity. To continue the study, we report in this short communication the different effects induced by the BjSEv and BjSv on isolated kidney and MDCK renal cells. BjSEv decreased perfusion pressure (PP) and renal vascular resistance (RVR) and increased urinary flow (UF) and glomerular filtration rate (GFR), while BjSv did not alter PP and RVR and reduced UF and GFR. Both types of venom, more expressively BjSEv, reduced %TNa+, %TK+ and %Cl−. In MDCK cells, the two types of venom showed cytotoxicity with IC50 of 1.22 &mgr;g/mL for BjSv and 1.18 &mgr;g/mL for BjSEv and caused different profiles of cell death, with BjSv being more necrotic. In conclusion, we suggest that BjSv is more nephrotoxic than BjSEv. HighlightsBothrops jararaca venoms from south and southeast Brazil have different renal effects.B. jararaca venom (Bjv) from south is more nephrotoxic than from Bjv from southeast.Bjv from south showed characteristics of renal injury on isolated kidney.Bjv from southeast showed a diuretic effect on isolated kidney.Bjv from south showed a higher necrotic profile than Bjv from southeast in MDCK cells.

Polarization microscopy as a tool for quantitative evaluation of collagen using picrosirius red in different stages of CKD in cats

Chronic kidney disease (CKD) is a relevant disease in feline clinic. The tubulointerstitial damage, with collagen deposition and fibrosis, is an important result of this process. The aim of this study was to quantify and correlate the deposition of collagen and severity of interstitial fibrosis (IF) in the kidney from cats in different stages of CKD. Kidney fragments from 10 adult cats with CKD were analyzed and stained by Massons trichrome (MT) and Picrosirius red (PSR) for circular polarized microscopy. Random quantitative analysis was performed on MT sections to classify the degree of IF, per field area, with and without circular polarization. Statistics correlations were performed by Spearmans (ρ; p < .05). There was a significant correlation of IF quantification with the area of interstitial collagen deposition by polarized PSR (PSRp) (r = .7939, p = .0098) and nonpolarized PSR (PSRn) (r = .7781, p = .0080). There was a positive correlation of serum creatinine (sCr) at different stages of CKD with PSRp (r = .7939, p = .0098), PSRn (r = .8667, p = .0027) and MT (r = .7818, p = .0117). Correlations between the percentage of quantified area was also positive from PSRp to PSRn (r = .9030, p = .0009) and PSRp to MT (r = .7939, p = .0098). The PSRN was also correlated with MT (r = .9273, p = .0001). The correlation with IF and sCr follows the disease evolution and the quantification of collagen by PSR is an excellent tool for analyzing the disease severity at different stages.

Crotalus durissus venom: biological effects and relevant applications. A Review

Snakes have an important biological role in the ecological chain, as well as in scientific researches performed with the venoms produced by them, since the enzyme-protein fractions these substances possess have been studied as pharmacological tools for the discovery of new therapies. Snakes of the genus Crotalus have gained significant relevance in the scientific field, since the venom produced by these reptiles has been the target of researchers in a few decades, due to the composition and the effects that these substances can produce. In Brazil, a single species represents the genus, which is Crotalus durissus. This review demonstrates that even with the advancement in scientific research on the composition, role and application of the venom produced by the subspecies of Crotalus durissus snake, it is necessary to further study their fractions and their action potential, which also demonstrates the how rich are these active components in different fields of biomedicine.

Clinical and laboratory diagnostic approach of intratbuluar sertolioma in a cryptorchid dog

Sertolioma is a common type of primary unilateral or bilateral testicular cancer, generally without signs that indicate the possibility of metastasis. This paper describes the clinical and laboratory diagnostic approach of a cryptorchid dog with sertolioma. The object of study was a male Pinscher dog, which reported the presence of a nodule in the inguinal region by its owner. Upon the nodule palpation during the physical examination, it was found the presence of edema and increased volume with firm consistency, but without fibrous features. Complete blood count, serum biochemical tests, ECG and echocardiogram, and fine-needle aspiration cytology were requested. Among other findings, cytology showed changes suggesting sertolioma: Numerous round and polygonal cells of large cytoplasm,

Gastrotomy in dog for removal of foreign body in caudal esophagus. Case report

Foreign bodies are digestible or not objects that can cause esophageal obstruction. Once located, the clinician must decide whether to observe its passage or perform the removal, being immediate intervention the most recommended. With that, we aimed to report a case of foreign body in the caudal esophagus of a canine, female, 8 years, with history of regurgitation and hyporexia. Based on anamnesis and physical examination findings, radiographs were performed in the laterolateral and ventrodorsal incidences, which showed the presence of radiopaque image (bone), confirming the presence of esophageal foreign body. In addition, ultrasound was requested and tests of serum biochemistry, all with no changes. As conduct, gastrostomy was performed to remove the bone and desobstruction.

Feline hypertrophic cardiomyopathy relevant aspects

Hypertrophic cardiomyopathy is a clinically heterogeneous disorder characterized by mild to severe thickening of left ventricular chamber associated with diastolic dysfunction. The main clinical signs are typically respiratory abnormalities secondary to pulmonary edema and/or pleural effusion; mild to severe acute heart failure; and paraparesis/paraplegia caused by arterial thromboembolism. The diagnosis should be based on a positive family history and the causes that cause secondary hypertrophy should be discarded. Echocardiography is currently the gold standard for the diagnosis of this pathology. It is the most common heart disease in adult cats; therefore, it is necessary knowledge of the condition in order to perform an effective clinical management, improving prognosis and quality of life of the animal.