Effect of external scrotal cooling on the viability of the testis with torsion in rats.

BACKGROUND AND AIM: Testicular damage due to ischemia during torsion is aggravated after reduction and reperfusion. The severity of the damage depends on the degree and duration of the torsion. Hypothermia has been successfully used in preserving the viability of ischemic organs for a prolonged period. Our aim is to evaluate the effect of external scrotal cooling in preserving testicular viability after spermatic cord torsion in rats. METHODS: 100 adult male Sprague-Dawley rats were equally divided into ten groups. Exposure of the right testicle for either 4 or 8 h in groups 1 and 2 were the control groups. The rats in eight groups (3-10) underwent clockwise torsion of 1,080 degrees of the right testis around its longitudinal axis, for either 4 or 8 h. External scrotal cooling was applied during the torsion period in four groups. Half of the rats were sacrificed at the end of the torsion period, while the other rats underwent detorsion and were sacrificed 2 weeks later. All testicles were excised for histology. RESULTS: The histological results showed that external scrotal cooling decreased both immediate and late damage to the testis, caused by torsion. A moderate degree of injury was found in the contralateral testicle in rats after torsion of the right testicle for 8 h with application of external cooling and detorsion. CONCLUSION: External scrotal cooling is effective in preserving the viability of the torsed testis in rats. The injury of ischemia-reperfusion, although reduced by external cooling, may endanger the contralateral testis as well, if the duration of torsion is longer than 4 h. With increased duration of torsion, orchiectomy should be considered. Application of this treatment may reduce the injury in humans awaiting surgery.

The presence of erythropoietin receptors in the human peripheral nervous system.

Erythropoietin (EPO) is a well-known hematopoietic factor and a major determinant of tissue oxygenation. EPO receptors have been identified on a wide variety of non-erythroid cell types including human central nervous system and peripheral nervous system of animal models. The presence or function of EPO receptors in human peripheral nervous system is unknown. By examining nerve segments from radicular and autonomic nerves using immunohistochemical methods, we demonstrated the presence of EPO receptors on myelin sheath of radicular nerves in the human peripheral nervous system.

The polymorphonuclear leukocyte--a new target for erythropoietin.

A previous study from our laboratory has shown that erythropoietin (EPO), beside its traditional role in erythropoiesis, acts as an alleviator of oxidative stress and inflammation in chronic hemodialysis (HD) patients, conferred in part by activated polymorphonuclear leukocytes (PMNLs). To substantiate this phenomenon, the existence of EPO receptors (EPO-Rs) on PMNL membrane was examined at the transcriptional and translational levels. mRNA for EPO-R was detected in PMNLs using specific primers directed towards the extracellular region of human EPO-R cDNA. The predicted 300-bp fragment was amplified by reverse transcriptase-polymerase chain reaction. Subcloning and sequence analysis revealed 100% homology of this fragment with human EPO-R. The receptor protein was detected on the surface of intact PMNLs using (125)I-EPO. The protein was further demonstrated by flow cytometric analysis using a fluorescent monoclonal anti-EPO-R. The percentage of PMNLs expressing EPO-R showed a strong correlation with the level of EPO in the serum, suggesting an upregulation of the receptor by the hormone. Taken together with our recent findings that EPO attenuates the oxidative stress and inflammation contributed by PMNLs in HD patients, the detection of functional EPO-R expression in PMNLs places these cells among the nonerythroid, EPO-responsive target populations.

Mesna: a novel renoprotective antioxidant in ischaemic acute renal failure.

BACKGROUND: Reactive oxygen species (ROS) play a key role in renal ischaemia-reperfusion injury. After establishing the in vitro anti-oxidative potential of mesna, a sulfhydryl-containing compound, its effect on kidney function and morphology in a rat model of ischaemic acute renal failure (ARF) was examined. METHODS: Mesna (180 mg/kg) was administered at different time points relative to ischaemia and/or reperfusion onset. Kidney function was assessed by glomerular filtration rate (GFR) and fractional sodium excretion (FE(Na)) before a 45-min period of unilateral renal artery clamping and following 90 min of reperfusion. Mesna was administered by bolus, 30 min before the induction of ischaemia, 5 min before ischaemia, 5 min before reperfusion, and 5 min after the onset of reperfusion. RESULTS: Mesna improved function of the ischaemic kidney at each administration. When mesna was administered 5 min before the onset of reperfusion, GFR reached 90-100% of its pre ischaemic value and FE(Na) was improved by 75%. The beneficial effect of mesna was also demonstrated by light and electron microscopy. Kidneys treated with mesna 5 min before reperfusion resembled ischaemic non-reperfused kidneys and showed subtle morphological and ultrastructural changes compared with ischaemic-reperfused kidneys. Mesna had no haemodynamic effect on renal blood flow and did not induce any osmotic diuresis. CONCLUSIONS: We suggest that mesna acts as an antioxidant. Its antioxidant potential together with optimal protection achieved when administered 5 min before reperfusion, supports the conclusion that mesna scavenges ROS generated at the onset of reperfusion, thus diminishing reperfusion injury and organ damage.

Successful pregnancy in a patient with polycystic kidney disease and advanced renal failure without prophylactic dialysis.

Pregnancies in women suffering from advanced chronic renal failure are frequently associated with deterioration of maternal renal function, premature births and low birth weights. Prophylactic dialysis is sometimes instituted since this intervention ameliorates the uremic milieu and improves maternal status and fetal uterine environment. This report describes a successful pregnancy and delivery in a hypertensive woman with advanced chronic renal failure due to polycystic kidney disease without accelerating the natural deterioration of renal function and without instituting prophylactic dialysis. The infant was delivered at full term with a normal birth weight. Thirty months after delivery, growth and development of the child were normal and the rate of deterioration of maternal renal function, assessed by 1/creatinine, was unaffected by pregnancy. Conservative management and effective control of blood pressure may be sufficient to achieve successful pregnancy outcome when women with advanced chronic renal failure become pregnant.

Involvement of peripheral polymorphonuclear leukocytes in oxidative stress and inflammation in type 2 diabetic patients.

OBJECTIVE: To determine the extent to which peripheral polymorphonuclear leukocytes (PMNs) contributed to oxidative stress (OS) and inflammation in type 2 diabetic patients. RESEARCH DESIGN AND METHODS: PMNs and plasma were separated from blood withdrawn from 18 type 2 diabetic patients and 16 age- and sex-matched normal control subjects. The rate of superoxide release from phorbol 12-myristate 13-acetate (PMA)-stimulated PMNs and the plasma glutathione (GSH) levels served as measures of OS. Inflammation was assessed by PMN recruitment, expressed by peripheral blood PMN counts, and the in vitro survival of PMNs, which reflects cell necrosis. RESULTS: PMA-stimulated PMNs from diabetes released superoxide significantly faster, and plasma-reduced GSH was lower in diabetic patients than in normal control subjects. The rate of superoxide release from diabetic PMNs showed no correlation with the plasma glucose concentrations, whereas a positive linear correlation with HbA1c was found. The in vitro survival of diabetic PMNs was lower than normal control PMNs when each was incubated in its own serum. The in vitro survival of normal control PMNs was reduced when incubated with diabetic serum, whereas normal control sera promoted the survival of diabetic PMNs. Peripheral PMN counts were higher in diabetic patients than in normal control patients. CONCLUSIONS: Type 2 diabetes is accompanied by a priming of PMNs, resulting in OS and increased self-necrosis. Necrosis starts a chain of inflammatory reactions that result in cell recruitment and in the long run, with OS, may result in endothelial dysfunction. Understanding the contribution of PMNs to OS and inflammation in diabetes may illuminate new mechanisms through which endothelial dysfunction evolves and causes angiopathy and atherosclerosis.

Oxidative stress during hemodialysis: effect of heparin.

BACKGROUND: Patients on chronic hemodialysis (HD) are exposed to oxidative stress. An HD session is used in this study as an in vivo model for studying the influence of heparin on oxidative stress caused partially by activated peripheral blood polymorphonuclear leukocytes (PMNLs) during a HD session. METHODS: Each patient underwent HD once with and once without heparin. Oxidative stress was determined by evaluating both the rate of superoxide release from phorbol 12-myristate 13-acetate (PMA)-stimulated PMNLs and plasma levels of oxidized glutathione (GSSG), both measured before and after the dialysis session. RESULTS: In vitro, heparin reduced the rate of superoxide release from separated PMA-stimulated PMNLs. In vivo, the rate of superoxide release from PMNLs was always increased after the dialysis session, regardless of the presence of heparin. However, in the presence of heparin, this increase was significantly smaller. The augmentation in the rate of superoxide release after the dialysis session without heparin was accompanied by a significant elevation of GSSG, reflecting a preceding oxidation of plasma glutathione. CONCLUSIONS: The increase in both parameters, the rate of superoxide release, and the plasma GSSG concentration after HD treatment suggest that heparin in vivo alleviates the oxidative stress induced by the dialysis process. Based on our results, heparin should be the anticoagulant of choice because of its suppressant action on HD-induced oxidative stress.

Jewish medicine and the University of Padua: contribution of the Padua graduate Toviah Cohen to nephrology.

During the period of the 11th to 17th century, the access of Jews to European universities was restricted and even those who were fortunate enough to be admitted to a university were not awarded a degree at the end of their studies. An exception to this situation was the University of Padua that allowed Jewish students to study and awarded them degrees; indeed 229 physicians graduated from this university between 1409 and 1721. Among these physicians there were many luminaries such as Joseph Del Medigo, Salmon Congeliano and Toviah Cohen. The latter made many contributions to the field of nephrology. In this treatise Maaseh Toviah he discussed uroscopy, kidney function, body fluid homeostasis and obstructive uropathy.

Interaction between erythropoietin and peripheral polymorphonuclear leukocytes in hemodialysis patients.

The effect of erythropoietin (EPO) on the oxidative stress and inflammation caused by polymorphonuclear leukocytes (PMNLs) in chronic hemodialysis (HD) patients was investigated in vivo and in vitro. The studies were performed on isolated PMNLs from peripheral blood of healthy controls and HD patients before and following 6 weeks of EPO treatment. The oxidative stress was expressed by the rate of superoxide release from phorbol 12-myristate 13-acetate stimulated PMNLs, and the inflammatory state was evaluated by in vitro PMNL survival, in addition to white blood cell and PMNL counts of the enrolled subjects. Following 6 weeks of EPO treatment, in HD patients, the rate of superoxide release from PMNLs as well as WBC and PMNL counts fell significantly when compared with the pretreatment values. PMNLs from HD patients and healthy controls incubated in vitro with increasing amounts of EPO displayed a significant reduction in their rates of superoxide release and a significant improvement in survival. We have concluded that EPO interacts with PMNLs, attenuating their primed state in HD patients, thus reducing oxidative stress and the extent of inflammation. To the best of our knowledge, this attenuation of the primed state of PMNLs by EPO is a new finding.

Renal ischemia-reperfusion injury: contribution of nitric oxide and renal blood flow.

The contributions of nitric oxide (NO) and renal blood flow (RBF) were examined in ischemia-reperfusion injury in the rat kidney. The function of both kidneys was assessed by glomerular filtration rate (GFR), and fractional excretion of sodium (FENa), calculated before, during unilateral renal artery clamping (45 min), and following reperfusion (90 min). RBF was measured in the same model by ultrasonic flowmetry. Intrarenal NO levels were modulated by administration of S-nitroso-N-acetylpenicillamine (SNAP), L-arginine, acetylcholine, and the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME). SNAP increased GFR from 0.20 +/- 0.04 ml/min in control ischemic kidney to 0.38 +/- 0.06 ml/min and reduced FENa from 19.3 +/- 3.4 to 9.5 +/- 1.8%. Similar results were observed when L-arginine was administered. Acetylcholine had no effect on GFR or FENa. RBF was fully restored within 60 min following reperfusion, with no change in the rate of recovery by L-arginine. L-NAME aggravated the ischemia-reperfusion injury, preventing full restoration of RBF, further reducing GFR and worsening FENa. In conclusion, ischemia-reperfusion injury ends in low intrarenal levels of NO. We propose that this low NO level results from damage to the endothelial receptor signal transduction process and is not due to impaired NO synthase activity or to changes in RBF.

Participation of peripheral polymorphonuclear leukocytes in the oxidative stress and inflammation in patients with essential hypertension.

Oxidative stress and inflammation have recently been linked to endothelial damage in essential hypertension (EH). Activated peripheral polymorphonuclear leukocytes (PMN) damage surrounding tissue by releasing reactive oxygen species (ROS) and proteolytic enzymes before self-necrosis. PMN necrosis further exacerbates inflammation and promotes chemotaxis and PMN recruitment. The number and properties of PMN from untreated EH patients is the focus of the present study. Oxidative stress was assessed by measuring the rate of superoxide anion release from separated, phorbol ester-stimulated PMN and the redox state of plasma glutathione. Inflammation was estimated indirectly by determining PMN number and their in vitro survival. PMN from EH patients (n = 37) released superoxide anion faster (P < .0001) than those of normotensives (NC, n = 37), 17.7 +/- 1.14 v 9.54 +/- 0.51 nmol/10 min/10(6) cells. The redox state of glutathione was twofold higher in EH plasma (P < .02) indicating systemic oxidative stress. PMN survival in vitro correlates linearly with the rate of superoxide release (r2 = 0.60, P < .02) and PMN count of EH patients, although in the normal range, were significantly higher (P < .0001), indicating necrosis and recruitment. Hypertensive plasma significantly reduced NC PMN viability, whereas normal plasma significantly increased EH PMN viability. What our studies show is that EH is accompanied by a primed state PMN that does not correlate with the levels of blood pressure. PMN priming in EH patients reflects an in vivo exposure to a constant stimulus ending in oxidative stress, increased self-necrosis, and cell recruitment. Oxidative stress and inflammation will result in endothelial damage and atherosclerosis in the long run.

[International quality assurance standards (ISO 9002) in an Israeli hospital].

This hospital has been certified by the Israel Standards Institute as having a quality assurance system fulfilling the requirements of the international standard, ISO 9002. This is the first hospital in this part of the world to be certified as fulfilling this standard. Its adoption is one of several accepted approaches to quality assurance in medicine. World-wide, very few health organizations, including hospitals, have implemented this system successfully. Opinions regarding its importance are divided, mostly because of lack of experience in its application. We describe its features, goals and structure, and its implementation in various sectors, including health organizations. The process of its adoption, application and implementation is described, and the problems which arose are discussed.

Influence of Judaism and Jewish physicians on Greek and Byzantine medicine and their contribution to nephrology.

Both the Old Testament and the Talmud contain a great deal of information on medicine, nephrology, health and disease. The basic premise of early Jewish medicine is based on the notion that disease is due to structural changes in internal organs. This is in contrast to the mythical dogma of humoralism as the basis of health and disease espoused by Hippocrates and Galen. The Old Testament and the Mosaic Codes provided the basis for modern public health and for the hygienic rules practised in our times. The Talmudists laid the foundations for the science of pathology as we know it today. These issues are discussed in detail and the contributions of three prominent medieval physicians (Asaph Judaeus, Isaac Judaeus and Maimonides) are presented.

Heparin induces apoptosis in human peripheral blood neutrophils.

Programmed cell death, by apoptosis, has been shown to play an important role in the regulation of haemopoiesis. Using trypan blue exclusion for distinguishing intact membranes, flow cytometry for detection of sub G1 peak and in situ terminal deoxynucleotidyl transferase mediated dUTP nick end labelling (TUNEL), this study shows that heparin induces apoptosis in vitro in human peripheral blood neutrophils. The known anti-proliferative effect of heparin in several in vitro cell systems has therefore to be interpreted in the light of apoptosis. In addition, apoptosis may help explain the anti-inflammatory effects resulting from the interaction between vessel wall heparan sulphate and chemoattracted peripheral blood neutrophils.

Short-term effect of erythropoietin on T-cell mitogenic proliferation in chronic renal failure patients.

Uremic patients undergoing hemodialysis (HD) are known to be highly susceptible to infections. Recent data indicate that in addition to its well-known stimulating effects on red cell production, erythropoietin (EPO) may also have immunomodulating properties. The aim of this study was to examine the effect of EPO on lectin-induced T-lymphocyte transformation in uremic patients, as part of its effect on the immune response. Sixteen HD patients and 20 age- and sex-matched healthy controls were compared before and after 6 and 20 weeks of EPO treatment. T lymphocytes were analyzed for their mitogenic activity following treatment with phytohemagglutinin (PHA), concanavalin A (CON A) and anti-CD3 by measuring 3H-thymidine incorporation. HD patients showed reduced mitogenic responses to all mitogens tested, compared to healthy controls. During the 6 weeks of EPO administration, a significant increase in T-lymphocyte activity could be demonstrated following exposure to all three mitogens (PHA, from 32 +/- 2 to 45 +/- 8; CON A, from 11 +/- 3 to 25 +/- 9; anti-CD3, from 11 +/- 3 to 22 +/- 5, means +/- SD). This increase was augmented after 5 months of EPO treatment. We conclude therefore that EPO improves in vitro T-cell mitogenic proliferation, even after short periods of treatment.

Immunohistochemical detection of p53 protein expression in HPV-induced condyloma acuminatum.

Immunohistochemical peroxidase staining for p53 protein was performed on 22 condyloma acuminatum tissue samples from patients infected with human papillomavirus (HPV). The purpose of our study was to understand the benign character of this syndrome. The patients studied were infected by HPV type 6 and 11. Two monoclonal antibodies, PAbs DO-1 and 240, were used to detect the p53 protein. Overexpression of wild-type p53 was found in the nuclei of the basal cell layers. In healthy tissues and non-infected patients no p53 protein expression was detected. We would like to speculate that infection with HPVs and their viral protein E7, which is implicated in disruption of normal growth, may regulate the induction of wild-type p53 over-expression, as is known for DNA-damaging agents such as UV- or X-radiation.

Parathyroid hormone and the cellular immune system.

Parathyroid hormone (PTH) is the main hormone controlling calcium concentration in the extracellular fluid (ECF) through its biological activity on bone, kidney and intestine. However, data published over the last two decades indicate that PTH may act as an immunomodulator. The purpose of the present review is to summarize the effects of PTH on various immune functions. Polymorphonuclear leukocytes of patients with chronic renal failure (CRF) and elevated blood levels of PTH showed impaired migration, reduced phagocytic and bactericidal activity, and inhibited granulocyte chemotaxis. Antibody production and T and B lymphocyte proliferation are affected by PTH, both in vivo and in vitro. Possible implications of the involvement of PTH and its fragments in CRF are discussed.

Antioxidant enzymes activity in polymorphonuclear leukocytes in chronic renal failure.

In the present study, activity of polymorphonuclear leukocyte (PMNL) intracellular antioxidant enzymes, i.e. catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPX), was assessed in CRF patients on hemodialysis (HD), or continuous ambulatory peritoneal dialysis (CAPD) and in healthy controls. The activity of SOD and GPX was reduced in HD and in CAPD (SOD: by 34.2 and 42%, respectively, and GPX 66 vs. 42%, respectively, taking the activity in normal controls as 100%). Catalase activity, on the other hand, was significantly augmented (298 and 175%, respectively) as compared to the healthy controls. This impairment in antioxidant enzymes activity, involved in the respiratory burst and phagocytosis, may contribute to the understanding of the reduced bactericidal ability of PMNL activity found in these patients.