Extracellular matrix remodeling of the testes through the male reproductive cycle in Teleostei fish

During the fish reproductive cycle, testes undergo morphological changes related to germinal epithelium and remodeling of extracellular matrix components (ECM). ECM is degraded mainly by action of matrix metalloproteinases (MMPs). Due to the natural renewal of ECM in fish testes, we choose Pimelodus maculatus to study remodeling of ECM throughout reproductive cycle, using picrosirius (to identify type I, II, III collagen) and reticulin (type III collagen), and to immunolocalize MT1-MMP (membrane type 1-matrix metalloproteinase) and MMP-2 in testis cells. Testes were classified in four reproductive phases: regenerating, development, spawning capable and regressing. Picrosirius and reticulin demonstrated a differential distribution of total collagen fibers during the reproductive cycle. Immunohistochemistry showed MT1-MMP only in acidophilic granulocyte cells mainly inside blood vessels, in connective tissue of capsule close to the germinal compartment, and also infiltrated in interstitial connective tissue. MMP-2 was detected in fibroblast and endothelial cells of interstitial and capsule blood vessels, in epithelial cells of capsule, and in acidophilic granulocyte cells at same description for MT1-MMP. The fish testes ECM were remodeled throughout reproductive cycle in according to morphophysiological alterations. During reproductive season (spawning capable), the interstitium increased in total collagen fibers (type I, II, III). After spermiation period (regression and regenerating), the amount of collagen fibers decreased in response to action of MMPs on collagen degradation and other interstitial components (not assessed in this study). MMPs seem to be indispensable components for natural cyclic events of ECM remodeling of fish testes and for guarantee tissue homeostasis throughout reproductive cycle.

Morphofunctional characterization of decellularized vena cava as tissue engineering scaffolds

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cardiovascular Complications following Chronic Treatment with Cocaine and Testosterone in Adolescent Rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Contribuição da utrassonografia para o diagnóstico do shunt portossistêmico em câes e gatos

Portosystemic shunt, an hepatobiliary anomaly, much common in dogs and less frequent in cats, can be detected by several diagnostic methods. Among them, the one which stands out is ultrasonography due to its numerous advantages: noninvasive, quick, accessible, relatively low cost and provides useful information relating to the other systems, apart from being a highly sensitive method. Portosystemic shunt diagnosis using ultrasonography becomes highly sensitive when associated with B-mode, color Doppler and pulsed Doppler. A bibliographic survey about portosystemic shunt ultrasonographic diagnosis was carried out, and the main ultrasonographic signals were: decreased hepatic size, difficulty in blood vessels visualization, presence of an anomalous vessel, tortuous with turbulent flow and, finally, increased portal blood flow velocity near the shunting vessel

Diferentes métodos de diagnóstico molecular na diferenciação das espécies de Sarcocystis spp

The Sarcocystis genus includes obligatory two-host life cycle protozoan parasites. It is the most numerous of the six genera of the Sarcocystidae family. The infection caused by parasites of this genus is a zoonotic and cosmopolitan disease known as sarcosistosis or sarcosporidiosis. The sarcositosis though frequently asymptomatic in its definitive hosts can be fatal in its intermediate hosts. The usual diagnoses of sarcosistosis takes place through a histological demonstration of schizonts in blood vessels and organs, and the presence of cysts in muscle tissue by necropsy or biopsy, this second method still more common and based on morphological features of the sarcocyst. However, these methods can be inadequate to a precise identification of the infector species once that, besides the genus being of numerous species, these often present similar morphological features. Another factor that makes the diagnostic more difficult is the non specificity of some Sacocystis species to their hosts. Consequently, molecular diagnostic methods have been used in order to identify the infector species and the parasite specific biological cycles, demonstrating also new species and coevolutive aspects between parasite and host. Among the most employed molecular techniques the Polimerase Chain Reaction (PCR), the nested-PCR and the Restriction Fragment Length Polymorphism (RFLP) stands out

Angiografia comparativa, prós e contras entre os métodos: por raios-X, Tomografia Computadorizada e Ressonância Magnética

By the early 20th century, the blood vessels could only be seen by anatomical studies. Shortly after the discovery of X-rays by Conrad Roentgen in 1895, the first experiments with radiographic imaging were performed with blood vessels. In 1905, the first experiment involving catheterization of arterial and venous system in dogs was performed and only in 1914 performed on living human patients. Parallel to these landmarks, there were advances in diagnostic imaging devices and the evolution of contrast substances was of utmost importance to the current angiography occupy a prominent role not only in terms of diagnosis, but also in the treatment of various disorders. The main objective of this review is to weave historical considerations and comparisons between the different methodologies used in angiography, because its importance; that may be in future, a veterinary diagnostic decisive test

Prostate hyperplasia caused by long-term obesity is characterized by high deposition of extracellular matrix and increased content of MMP-9 and VEGF

Recent studies have shown a positive association of cancer and obesity, but the morphological and molecular mechanisms involved in this relationship are still unknown. This study analysed the impact of long-term obesity on rat prostate, focusing on stromal changes. Male adult Wistar rats were treated with high-fat diet to induce obesity, while the control group received a balanced diet. After 30 weeks of feeding, the ventral prostate was analysed by immunohistochemistry for cell proliferation, smooth muscle α-actin, vimentin, chondroitin sulphate and metalloproteinases (MMP-2 and 9). The content of androgen receptor (AR), oestrogen receptors (ERs) and vascular endothelial growth factor (VEGF) was measured by Western blotting, and activity of catalase and Glutathione-S-Transferase (GST) were quantified by enzymatic assay. Long-term obesity decreased testosterone plasma levels by 70% and resulted in stromal prostate hyperplasia, as evidenced by increased collagen fibres. Such stromal hyperplasia was associated with increased number of blood vessels and raised VEGF content, and increased expression of chondroitin sulphate, vimentin, α-actin and MMP-9. In spite of the high cell density in prostate, the proliferative activity was lower in the prostates of obese rats, indicating that hyperplasia was established during the early phases in this obesity model. AR levels increased significantly, whereas the ERα decreased in this group. Moreover, the levels of catalase and GST were changed considerably. These findings indicate that long-term obesity, besides disturbing the antioxidant control, causes intense stromal remodelling and release of factors that create an environment that can promote proliferative disorders in the gland, culminating with diffuse hyperplasia.

A punção subaracnoidea sobre tatuagem determina alterções histológicas sobre o tecido nervoso e as meninges?

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Immunohistochemical evaluation of vascular endothelial growth factor (VEGF) in splenic hemangiomas and hemangiosarcomas in dogs

Formation of new blood vessels is paramount for tumour growth and metastatic dissemination and vascular endothelial growth factor (VEGF) is one of the key regulators of this process. The purpose of this study was to evaluate the immunohistochemical expression of VEGF in 23 splenic hemangiosarcomas and 7 splenic hemangiomas in dogs. Blood tests performed previous to splenectomy were analysed for correlation with tumour VEGF expression. Results showed significantly higher VEGF expression in hemangiosarcomas than hemangiomas and lower hematocrit values and red cell count in dogs affected with malignant neoplasia (P < 0.05). These findings suggest the presence of high VEGF levels may be related to the malignant vascular proliferation seen in hemangiosarcomas.

Absence of Wharton's jelly: case report

There are few reports in the literature of the absence of Wharton's Jelly. Here we report the seventh case in a primigravida, 22 years old, admitted after vaginal delivery of stillborn. The umbilical cord have a long segment with disruption of cord structures and the three blood vessels were completely separated from each other, with a minimum amount of Wharton's jelly remaining around each vessel. The absence of Wharton' jelly is associated with fetal distress, intrauterine growth restriction, and fetal death. Quantitative/qualitative studies of Wharton's jelly represent an open field of research for possible correlations with obstetric conditions and fetal deaths.

Efeitos preventivos do exercício físico sobre as proteínas ciclooxigenase-2 (COX-2) e fator de crescimento de vasos derivado do endotélio (VEGF) no músculo cardíaco em ratos tratados com dexametasona

Dexamethasone (DEXA) is a synthetic glucocorticoid widely used in the handling of several drugs, for its proven benefits in fighting inflammation and allergies. Despite their benefits, their chronic use leads to several side effects that include changes in the body in the metabolism of carbohydrates, lipids and proteins. Moreover, being an anti-inflammatory, acts on the arachidonic acid pathway, reducing the expression of the enzyme cyclooxygenase (COX-2) and growth factor derived from the endothelium of blood vessels (VEGF) in various tissues. However, its effects on the myocardium are still uncertain. The physical training (PT), in turn, promotes effects contrary to those caused by chronic use of DEXA, however, little is known about the preventive effects of TF in the side effects of Dexa in the myocardium. Therefore, the aim of this study was to determine if the TF has the ability to prevent and/or mitigate the effects of Dexa in protein expression of COX-2 and VEGF in the myocardium. Forty animals were divided into 4 groups: sedentary control (SC), sedentary treated with Dexa (SD), trained control (TC) and Trained treated with Dexa (TD) and submitted to a protocol of physical training on the treadmill for 70 days (1 h/day-5 days per week, 60% of physical capacity) or kept sedentary. Over the past 10 days, rats were treated with Dexa (Decadron, 0.5 mg/kg per day, ip) or saline. During training the animals were weighed weekly and during treatment daily. At the end of treatment was made to measure fasting glucose levels of animals. The rats were killed with excess anesthesia and cardiac muscle was removed, weighed, homogenized, centrifuged and stored at -20° C for analysis of protein expression of VEGF and COX-2 by Western blotting technique. Treatment with dexamethasone caused a weight loss of 18% in sedentary animals and 13% in trained as well as elevated levels of fasting glucose in sedentary (88%). The TF was unable to mitigate the loss in...

Zinc supplementation for the prevention of type 2 diabetes mellitus in adults with insulin resistance

BackgroundDiabetes is associated with long-term damage, dysfunction and failure of various organs, especially the eyes, kidneys, nerves, heart and blood vessels. The risk of developing type 2 diabetes increases with age, obesity and lack of physical activity. Insulin resistance is a fundamental aspect of the aetiology of type 2 diabetes. Insulin resistance has been shown to be associated with atherosclerosis, dyslipidaemia, glucose intolerance, hyperuricaemia, hypertension and polycystic ovary syndrome. The mineral zinc plays a key role in the synthesis and action of insulin, both physiologically and in diabetes mellitus. Zinc seems to stimulate insulin action and insulin receptor tyrosine kinase activity.ObjectivesTo assess the effects of zinc supplementation for the prevention of type 2 diabetes mellitus in adults with insulin resistance.Search methodsThis review is an update of a previous Cochrane systematic review published in 2007. We searched the Cochrane Library (2015, Issue 3), MEDLINE, EMBASE, LILACS and the ICTRP trial register (frominception toMarch 2015). There were no language restrictions. We conducted citation searches and screened reference lists of included studies.Selection criteriaWe included studies if they had a randomised or quasi-randomised design and if they investigated zinc supplementation compared with placebo or no intervention in adults with insulin resistance living in the community.Data collection and analysisTwo review authors selected relevant trials, assessed risk of bias and extracted data.Main resultsWe included three trials with a total of 128 participants in this review. The duration of zinc supplementation ranged between four and 12 weeks. Risk of bias was unclear for most studies regarding selection bias (random sequence generation, allocation concealment) and detection bias (blinding of outcome assessment). No study reported on our key outcome measures (incidence of type 2 diabetes mellitus, adverse events, health-related quality of life, all-cause mortality, diabetic complications, socioeconomic effects). Evaluation of insulin resistance as measured by the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) showed neutral effects when comparing zinc supplementation with control (two trials; 114 participants). There were neutral effects for trials comparing zinc supplementation with placebo for total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol and triglycerides (2 studies, 70 participants). The one trial comparing zinc supplementation with exercise also showed neutral effects for total cholesterol, HDL and LDL cholesterol, and a mean difference in triglycerides of -30 mg/dL (95% confidence interval (CI) -49 to -10) in favour of zinc supplementation (53 participants). Various surrogate laboratory parameters were also analysed in the included trials.Authors'conclusionsThere is currently no evidence on which to base the use of zinc supplementation for the prevention of type 2 diabetes mellitus. Future trials should investigate patient-important outcome measures such as incidence of type 2 diabetes mellitus, health-related quality of life, diabetic complications, all-cause mortality and socioeconomic effects.

Prognostic value of vascular endothelial growth factor and hypoxia-inducible factor 1 alpha in canine malignant mammary tumors

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morphology and Histochemistry of the Liver of Carnivorous Fish Hemisorubim platyrhynchos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Skeletal muscle degeneration and regeneration after injection of bothropstoxin-II, a phospholipase A2 isolated from the venom of the snake Bothrops jararacussu

A myotoxic phospholipase A2, named bothropstoxin II (BthTX-II), was isolated from the venom of the South American snake Bothrops jararacussu and the pathogenesis of myonecrosis induced by this toxin was studied in mice. BthTX-II induced a rapid increase in plasma creatine kinase levels. Histological and ultrastructural observations demonstrate that this toxin affects muscle fibers by first disrupting the integrity of plasma membrane, as delta lesions were the earliest morphological alteration and since the plasma membrane was interrupted or absent in many portions. In agreement with this hypothesis, BthTX-II released peroxidase entrapped in negatively charged multilamellar liposomes and behaved as an amphiphilic protein in charge shift electrophoresis, an indication that its mechanism of action might be based on the interaction and disorganization of plasma membrane phospholipids. Membrane damage was followed by a complex series of morphological alterations in intracellular structures, most of which are probably related to an increase in cytosolic calcium levels. Myofilaments became hypercontracted into dense clumps which alternated with cellular spaces devoid of myofibrillar material. Later on, myofilaments changed to a hyaline appearance with a more uniform distribution. Mitochondria were drastically affected, showing high amplitude swelling, vesiculation of cristae, formation of flocculent densities, and membrane disruption. By 24 hr, abundant polymorphonuclear leucocytes and macrophages were observed in the interstitial space as well as inside necrotic fibers. Muscle regeneration proceeded normally, as abundant myotubes and regenerating myofibers were observed 7 days after BthTX-II injection. By 28 days regenerating fibers had a diameter similar to that of adult muscle fibers, although they presented two distinctive features: central location of nuclei and some fiber splitting. This good regenerative response may be explained by the observation that BthTX-II does not affect blood vessels, nerves, or basal laminae. © 1991.