Effect of different glycosaminoglycans in a guinea-pig carotid-artery thrombosis model

Heparin is the most frequently used drug for the prevention and treatment of thrombosis. Its use, however, is restricted by its side-effects. To study the efficacy of other glycosaminoglycans that could substitute heparin in the management of arterial thrombosis, 60 guinea-pigs were randomly allocated into 6 groups: G1= control, G2= heparin (150 IU/kg), G3= heparan sulfate from beef pancreas (2.5 mg/kg), G4= heparan sulfate from beef lung (2.5 mg/kg), G5= N-acetylated heparan from beef pancreas, G6= dermatan sulfate from beef intestine (2.5 mg/kg). Ten minutes after intravenous injection of the drugs, thrombosis was induced by the injection of a 50% glucose solution into a segment of the right carotid artery isolated between 2 thread loops during 10 minutes. Three hours later the artery was re-exposed and if a thrombus was present it was measured, withdrawn and weighed. Thrombin time and activated partial thromboplastin time were measured in all animals. Thrombus developed in 90% of the animals in the control group, 0% in G2 and G3, 62.5% in G4, 87.5% in G5 and G6. Only in the animals treated with heparin the coagulation tests were prolonged. In conclusion, in the used dose only the heparan sulfate from beef pancreas presented an antithrombotic effect similar to heparin in this experimental model.

Renal artery clipping attenuates the progression of adriamycin nephropathy

This study was designed to analyze the impact of diminished renal perfusion pressure due to renal clipping on the rat model of adriamycin nephropathy. Male Wistar rats, divided into four groups (n = 9 per group) were injected with saline as control (C), adriamycin 3 ml/kg (Ad), saline with the left renal artery clipped (Rv), and adriamycin plus clip (AdRv). After 24 weeks mean arterial pressure (MAP), inulin, and p-aminohippurate (PAH) clearances were performed to evaluate renal function. Morphologic analysis included histologic criteria of percentage of glomerulosclerosis and tubulointerstitial lesion index (TILI). The MAP (mm Hg) was similar between Rv (143 +/- 13) and AdRv (154 +/- 20), but higher (P < .05) than C (120 +/- 8) and Ad (124 +/- 11). Inulin clearance (mL/min/100 g) in Ad (0.2 +/- 0.05) was smaller than in C (0.53 +/- 0.17) and Rv (0.4 +/- 0.01) (P < .05), and was at an intermediate level in AdRv (0.33 +/- 0.2). The level of PAH (mL/min/100 g) was normal at 1.76 in C, and diminished more in Ad (0.58) than in Rv (1.06) and AdRv (1.18) (P < .05). Both Ad and the AdRv nonclipped kidneys had the highest degree of glomerulosclerosis (33% and 25%) and TILI (7% and 8%), respectively, compared with C and Rv (both 0%), whereas the clipped kidneys displayed intermediate degrees (9% and 5%) (P < .05 v nonclipped). The data suggest that diminished perfusion pressure of the clipped kidney, by decreasing the intraglomerular pressure, protects the glomerulus from damage and attenuates the evolution of adriamycin nephropathy. Am J Hypertens 1998;11:1124-1128 (C) 1998 American Journal of Hypertension, Ltd.

Frequency of coronary artery disease in patients with renal artery stenosis without clinical manifestations of coronary insufficiency

Atherosclerotic renal artery stenosis (RAS) and coronary artery disease (CAD) arise from the same multiple risk factors. The purpose of this study was to assess the frequency of previously undiagnosed CAD in patients with angiographically confirmed RAS, by conducting coronary arteriography in the same setting. of 57 consecutive patients referred for renal arteriography on clinical grounds during a 14-month period, 28 had no RAS and 6 had RAS, but previously documented CAD. of the remainder 23 patients. 17 (74%; CI 56%-92%) had both RAS and CAD (7 single vessel, 4 two-vessel, and 7 multivessel disease). The clinical characteristics, such as age, blood pressure (BP) levels, signs of heart failure, were no different between those with and without CAD, although the 4 diabetic patients, the 4 patients with fundoscopic findings of grade III retinopathy, 11 of 14 with peripheral arterial disease, and 7 of 8 patients with prior stroke belonged in the CAD group. None developed complications as a result of the two consecutive procedures. The data suggest that in patients with RAS the frequency of silent CAD is high and cannot be predicted on clinical grounds alone, therefore coronary angiography should be routinely recommended in the same setting.

Immunohistochemical evaluation of Ki-67 and PCNA in canine mammary neoplasias: Correlation with prognostic factors and clinical outcome

E-cadherin is a cell-cell adhesion molecule and low e-cadherin expression is related to invasiveness and may indicate a bad prognosis in mammary neoplasms. The expression of cell proliferation markers PCNA and especially Ki-67, has also proved to have a strong prognostic value in this tumor class. The expression of these markers was related to the clinical-pathological characteristics of 73 surgically removed mammary tumors in female dogs by immunohistochemistry. There was no statistical correlation between these markers and death by neoplasm, survival time and disease-free interval. However, the loss of e-cadherin expression and marked Ki-67 expression (p=0.016) were considered statistically significant for the diagnosis (p=0.032). When evaluated as independent factors, there was evidence of the relationship between the loss of e-cadherin expression and high PCNA expression with changes in the body status (divided into obese, normal and cachectic) of female dogs (p=0.030); there was also evidence of the relationship between pseudopregnancy and e-cadherin alone (p=0.021) and for ulceration and PCNA alone (p=0.035). The significant correlation between the markers expression and these well known prognostic factors used individually or in combination suggests their prognostic value in canine mammary tumors.

Immunohistochemical and molecular expression of laminin-332 gamma-2 chain in canine mammary tumors

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

Effect of continuous and pulsed therapeutic ultrasound in the appearance of local recurrence of mammary cancer in rats

Purpose: Ultrasound (US) therapy is an elect rot hermotherapeutic modality that uses US energy to provoke physical and chemical alterations. US therapy has been widely used in physical therapy. However in clinical practice, it is contra-indicated in cancer patients due to the possibility of exacerbating tumor growth.Methods: Sixty-eight female Sprague-Dawley rats bred in UNIFAE vivarium were studied. At 50 days of age, 7, 12-dimetylbenz(a)anthracene (7, 12-DMBA) was administered to 35 rats by gastric gavage to induce mammary cancer After 90 days the mammary glands of the rats belonging to the group with mammary cancer induction and stimulated by US were removed. Animals received either continuous or pulsed US. US waves were generated at a frequency of 1 MHz during 10 days, with an intensity dose of 0.5 W in the continuous group, and 0.9 W (duty cycle: 20%) in the pulsed group.Results: Among the rats treated with continuous US, 44.4% developed local recurrence, while among the rats treated with pulsed US, 22.2% had local tumor recurrence (p < 0.05). No evidence of distant metastases was shown in any of the rats studied.Conclusion: The use ofcontinuous and pulsed therapeutic US promoted the development of local recurrence of mammary cancer in female Sprague-Dawley rats in the postoperative period.

Interleukin-8 as a prognostic serum marker in canine mammary gland neoplasias

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

Conventional and Doppler ultrasound for the differentiation of benign and malignant canine mammary tumours

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