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Biomedical subjects

Z Nagy

Publications and source records attributed to Z Nagy.

At least 127 records · Page 7Linked to original sources

Distribution of spermatogenesis in the testicles of azoospermic men: the presence or absence of spermatids in the testes of men with germinal failure.

The aim of the study was to determine whether a prior diagnostic testicle biopsy can predict success or failure of testicular sperm extraction (TESE) with intracytoplasmic sperm injection (ICSI) in patients with non-obstructive azoospermia caused by testicular failure, and what is the minimum threshold of sperm production in the testis which must be surpassed for spermatozoa to reach the ejaculate. Forty-five patients with non-obstructive azoospermia caused by testicular failure underwent diagnostic testicle biopsy prior to a planned future TESE-ICSI procedure. The diagnostic testicle biopsy was analysed quantitatively, and correlated with the quantitative findings of spermatogenesis in patients with normal spermatogenesis, as well as with the results of subsequent attempts at TESE-ICSI. Men with non-obstructive azoospermia caused by germinal failure had a mean of 0-6 mature spermatids/seminiferous tubule seen on a diagnostic testicle biopsy, compared to 17-35 mature spermatids/tubule in men with normal spermatogenesis and obstructive azoospermia. These findings were the same for all types of testicular failure whether Sertoli cell only, maturation arrest, cryptorchidism, or post-chemotherapy azoospermia. Twenty-two of 26 men with mature spermatids found in the prior testis biopsy had successful retrieval of spermatozoa for ICSI, 12 of their partners became pregnant, and are either ongoing or delivered. The study suggests that 4-6 mature spermatids/tubule must be present in the testis biopsy for any spermatozoa to reach the ejaculate. More than half of azoospermic patients with germinal failure have minute foci of spermatogenesis which are insufficient to produce spermatozoa in the ejaculate. Prior diagnostic testicle biopsy analysed quantitatively (for the presence of mature spermatids) can predict subsequent success or failure with TESE-ICSI. Incomplete testicular failure may involve a sparse multi-focal distribution of spermatogenesis throughout the entire testicle, rather than a regional distribution. Therefore, it is possible that massive testicular sampling from many different regions of the testes may not be necessary for successful TESE-ICSI.

Biopsy↗

The effect of female age and ovarian reserve on pregnancy rate in male infertility: treatment of azoospermia with sperm retrieval and intracytoplasmic sperm injection.

Factors other than spermatozoa could be the major determinant of the success of assisted reproduction treatment in cases of male infertility. Our aim was to evaluate the effect of the wife's age and ovarian reserve on assisted reproduction success rates in the most severe type of male infertility, i.e. azoospermia. A total of 249 consecutive couples suffering from male infertility caused by azoospermia underwent microsurgical epididymal sperm aspiration (MESA) or testicular sperm extraction (TESE) with intracytoplasmic sperm injection (ICSI). Of these men, 186 had irreparable obstructive azoospermia, and 63 had non-obstructive azoospermia due to testicular failure. Neither the pathology, the source, the quantity, nor the quality of spermatozoa had any effect on fertilization or pregnancy rates. Maternal age and ovarian reserve (number of eggs) had no effect on fertilization or embryo cleavage, but did dramatically affect the embryo implantation, pregnancy and delivery rates. Wives of azoospermic men who were in their 20s had a 46% live delivery rate per cycle, wives aged 30-36 years had a 34% live delivery rate per cycle, wives aged 37-39 years had a 13% live delivery rate per cycle, and wives > or = 40 years had only a 4% live delivery rate per cycle. The number of eggs retrieved also affected pregnancy and delivery rate, but to a lesser extent than age. In virtually all cases of obstructive azoospermia, and in 62% of cases with non-obstructive azoospermia caused by germinal failure, sufficient spermatozoa could be retrieved to perform ICSI, with normal fertilization and embryo cleavage. However, the pregnancy rate and the live delivery rate were dependent strictly on the age of the wife, and on her ovarian reserve. Unfortunately, exaggerated claims of high pregnancy rates can thus easily be made by manipulating, in a very simple way, selection for female factors.

Adult↗

Ovulation by repeated human chorionic gonadotrophin in 'empty follicle syndrome' yields a twin clinical pregnancy.

This case illustrates the possibility of obtaining oocytes that fertilize and cleave normally after the administration of a second ovulatory dose of human chorionic gonadotrophin (HCG) in a case of 'empty follicle syndrome'. The present patient underwent ovarian stimulation with gonadotrophin-releasing hormone analogue (GnRHa)/menotropin for intracytoplasmic sperm injection (ICSI). After the failure of the first oocyte retrieval, a second dose of HCG was administered to trigger ovulation. A total of 13 oocytes was retrieved during the second procedure and 11 good quality embryos were obtained (fertilization and cleavage rates of 92 and 91% respectively). No pregnancy was achieved after the replacement of three embryos. In a subsequent cycle stimulated with clomiphene citrate, three frozen-thawed embryos were replaced and a twin pregnancy was achieved. The patient delivered two healthy babies at term.

Adult↗

The effects of additional pathology on the cognitive deficit in Alzheimer disease.

The diagnosis of Alzheimer disease (AD) according to current criteria is a combined clinical and pathological exercise. The clinical discrimination of AD from other types of dementia may be complicated when the patient suffers from more than one disease. In particular the concomitant presence of other neurological conditions may significantly influence the severity of cognitive deficit. In this study we analyze the extent of the influence of vascular and other neurodegenerative pathology on the cognitive deficit in a consecutive series of 88 prospectively assessed elderly subjects. We find that, for any given level of cognitive deficit, the densities of either all plaques or neuritic plaques alone in the neocortex are significantly lower in cases of AD mixed with other CNS pathology than in cases of AD with no other CNS pathology. In AD combined with cerebrovascular disease, the total plaque density makes a significant contribution to cognitive deficit, while neurofibrillary tangle (NFT) densities do not. In contrast, in pure AD tangle density is the major determinant of cognitive deficit. Our findings draw attention to the influence of coexisting brain pathologies on the clinical manifestation of dementia in subjects with AD. These findings indicate that pathological diagnostic criteria for AD should take into account such additional pathology in demented subjects. They also improve understanding of the circumstances in which the amyloid component of AD can play a decisive role in precipitating clinical dementia.

Aged↗

Effects of tumor necrosis factor and pentoxifylline on ICAM-1 expression on human polymorphonuclear granulocytes.

Intercellular adhesion molecule-1 (ICAM-1) is a cytokine-inducible adhesion molecule, expressed on cells of multiple lineages at the site of inflammation. Cytofluorometric analysis revealed that CD16-positive peripheral blood polymorphonuclear leukocytes (PMNs, neutrophils) expressed ICAM-1 on their surface, and it was upregulated by in vitro stimulation with tumor necrosis factor (TNF), GM-CSF and Staphylococcus aureus. The S. aureus-induced stimulation of ICAM-1 expression was inhibited by pentoxifylline (PTX). As TNF is a potent inducer of ICAM-1 expression, it is concluded that in these experiments the inhibition of TNF production by PTX concomitantly resulted in the inhibition of the upregulation of ICAM-1. However, the inhibition of granulocyte apoptosis by PTX might be of importance in this process. The present study provides evidence that cytokine-stimulated neutrophils are able to express the adhesion molecule ICAM-1 and this may allow ICAM-1-positive neutrophils to physically interact with LFA-1-positive inflammatory cells. The preliminary results demonstrate that the basal expression of ICAM-1 on PMNs of septic patients is higher than that in the case of normal blood donors. Further studies will elucidate the in vivo relevance of cytokine-induced neutrophil ICAM-1 expression and the potential role of its inhibition by PTX in inflammatory response disorders.

Apoptosis↗

Heritability analysis of lipids and three gene loci in twins link the macrophage scavenger receptor to HDL cholesterol concentrations.

We studied 100 healthy monozygotic and 72 dizygotic twin pairs (mean age, 34 +/- 14 years) to test for genetic influences on blood lipids and to examine relevant gene loci. Total cholesterol (TC), LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), and triglyceride (TG) levels were determined after a 12-hour fast. Zygosity was determined with the use of microsatellite markers. Heritability estimates were conducted by using the lisrel 8 program; a sib-pair analysis was conducted by using the sibpal program. Linear regression analyses were carried out between identical-by-descent status and squared within-pair differences of TC, LDL-C, HDL-C, and TG values. Heritability estimates of the lipid serum concentrations ranged from .58 to .66. A significant linkage relationship was found for HDL-C (P = .008) and TGs (P = .05) with D8S261 on chromosome 8p. However, no linkage was found between any of the lipid variables and the lipoprotein lipase gene locus (LPL GZ14/15 and D8S282). Because D8S261 is located approximately halfway between the LPL and macrophage scavenger receptor genes, we examined the nearby markers D8S549 and D8S1731. Linkage was found for HDL-C and D8S549 (P = .001) and for HDL-C and D8S1731 (P = .04). On the other hand, we found no linkage between the LDL receptor gene locus and LDL-C serum concentrations nor between the LPL gene locus and the various other lipid fractions. Our data suggest a significant influence of the macrophage scavenger receptor gene locus on HDL-C and weak influence on TG levels. We suggest that inherited variability in the macrophage scavenger receptor gene has an influence on serum lipid concentrations.

Adult↗

Endothelial adhesion molecules and leukocyte integrins in preeclamptic patients.

Endothelial cell activation is important in the pathogenesis of preeclampsia; however, the nature of the activation is unknown. We investigated 22 patients with preeclampsia. 29 normotensive pregnancies, and 18 nonpregnant women to test the hypothesis that serum from preeclamptic patients induces expression of intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) and stimulates intracellular free calcium concentrations [Ca2+]i in cultured endothelial cells. We then asked whether the corresponding integrin adhesive counter receptors lymphocyte function-associated antigen-1 (CD11a/CD18), macrophage-1 antigen (CD11b/CD18), p150,95 (CD11c/CD18), and very late activation antigen-4 (CD49/CD29) are increased in patients with preeclampsia. In the pregnant women, the measurements were conducted both before and after delivery. Integrin expression was measured by fluorescent antibody cell sorting analysis using monoclonal antibodies. ICAM-1 and VCAM-1 were analyzed on endothelial cells by enzyme-linked immunosorbent assay. [Ca2+]i was measured with fura 2. Serum from preeclamptic patients increased endothelial cell ICAM-1 expression but not VCAM-1 expression. Preeclamptic patients' serum also increased [Ca2+]i in endothelial cells compared with serum from normal nonpregnant or normal pregnant women. Endothelial cell [Ca2+]i concentrations were correlated with the ICAM-1 expression in preeclamptic patients (r = .80, P < .001) before but not after delivery. Expression of the integrin counter receptors on leukocytes was similarly increased in preclampsia and normal pregnancy compared with the nonpregnant state. The expression decreased significantly after delivery in both groups. Our results demonstrate that serum from preeclamptic women induces increased ICAM-1 surface expression on endothelial cells, while the expression of the integrin counterreceptors was not different. The effect on endothelial cells may be related to an increase in [Ca2+]i. The effect on cultured endothelial cells and the rapid decrease after delivery suggests the presence of a circulating serum factor which increases endothelial cell [Ca2+]i and enhances adhesion molecule expression.

Adult↗

Scleral reinforcement in progressive myopia and intraoperative ultrasound control of the cadaver fascia lata strip.

Scleral reinforcement (sustentaculum sclerae) is one of the operations against myopia. During the progression of myopia the eye grows. The chorioretinal layer can only moderately follow the expansion of the sclera, and mostly this is the cause of the complications that can cause permanent visual acuity decrease. The aim of the operation is to strengthen the posterior part of the sclera by implantation of a cadaver fascia lata strip, that slows down or stops the expansion of the eyeball, and this way prevents the development of complications. At our Department we perform the Snyder-Thompson technique. Between 1984 and 1994 343 operations were performed at our Department. We followed up the changes of the axial lengths by ultrasound (A-mode) examinations. The axial length decreased in 43.7% remained unchanged in 22.2% and increased in 34.1% of the cases. We controlled the location of the strip intra- and postoperatively with B-mode ultrasound. Nowadays scleral reinforcement is still the only possibility to stop or slow down the expansion of the eyeball in cases of progressive high myopia.

Cadaver↗

Relevance of cytokine production to infected pancreatic necrosis.

The purpose of this study was to evaluate the role of cytokines in septic conditions following acute pancreatitis and to elaborate a new strategy in the treatment. Increased TNF and IL-6 serum levels were found in 30% of the patients (n = 40), while the IL-6 level was elevated in all of them. There was a positive correlation between the serum IL-6 and sICAM-1 levels. The in vitro TNF and IL-6 producing capacities were initially higher in the study group, but decreased on subsequent days, especially in fatal cases (n = 3). Administration of pentoxifylline [PTX] (400 mg/day) to septic patients following necrotizing pancreatitis resulted in TNF and IL-6 production similar to that observed in control donors. The level of sICAM-1 also decreased following PTX therapy. These results suggest that cytokines produced by activated leucocytes are important in the pathogenesis of infected pancreatic necrosis, and their inhibition might be of therapeutic advantage.

APACHE↗

Plasma levels of TNF and IL-6 following induction of acute pancreatitis and pentoxifylline treatment in rats.

Activation of cytokine cascade is a decisive factor in determining the pathobiology of different inflammatory processes including acute pancreatitis. The purposes of this study were to determine the TNF and IL-6 levels after the induction of acute necrotizing pancreatitis, and to establish the effects of pentoxifylline on the cytokine production and the severity of pancreatitis. Acute necrotizing pancreatitis was induced by the retrograde injection of 200 microliters taurocholic acid into the pancreatic duct in male Wistar rats. TNF was titrated in a bioassay on cell line WEHI clone 164. IL-6 was measured via its proliferative action on the IL-6 dependent mouse hybridoma cell line B-9. Seven mg/kg pentoxifylline was administered intraperitoneally at the time of operation and/or 24 hours later. Rats were sacrificed, 48 or 72 hours after the operation. The TNF bioassay revealed high levels of TNF (36.6 +/- 6.0 U/ml) in the control group whereas levels decreased to zero in the pentoxifylline-treated group. The IL-6 bioassay likewise demonstrated high levels of IL-6 in the control group and markedly decreased levels in the pentoxifylline treated group (7083 +/- 2844 pg/ml, 6463 +/- 1307 pg/ml vs. 137.5 +/- 85.5 pg/ml, respectively, p < 0.05). The high mortality observed in the control group (43%) was sharply decreased by pentoxifylline administration to 11%. The data suggest that pentoxifylline is capable of modifying the cytokine production after 48 hours of induction of acute pancreatitis.

Amylases↗

Intrastromal corneal ring, a new refractive surgical technique to decrease myopia. Experimental and clinical results.

From among the wide range of keratorefractive operations, the authors applied the intrastromal corneal ring (ICR) technique to treat myopia. The results of operations performed on dogs' eyes were evaluated using slit lamp investigations, cornea topography and histological investigations. In the possession of favourable results, this kind of operation was successfully performed on three patients suffering from expressed unilateral myopia, too. The desired optical results (10.0 dioptres) proved to be permanent 3-10 months after surgery and were demonstrated by the patients' visual acuity as well as cornea topographic examinations. The surrounding of the PMMA ring situated intrastromally and the substance of the cornea remained calm and clear, respectively. The authors think that the ICR technique can successfully be applied in the treatment of myopia similarly to refractive surgical interventions such as radial keratotomy (RK) and excimer laser photorefractive keratectomy (PRK), which are widely used methods these days.

Animals↗

Idiopathic scoliosis--new surgical methods or search for the reasons.

Idiopathic scoliosis (IS) is a deformity of the spine whose aetiology is unknown despite of extensive clinical and basic research work. The significance of this disease lies in the consequences of a spine deformity (deformation of the chest, compromise of the cardio-pulmonar function, compression of the neurological elements, severe somatic and psychological sufferings). According to statistical data, one third of the idiopathic scoliotic cases progress and need surgical intervention. Cotrel and Dubousset introduced the three dimensional correction surgical method for the treatment of spine deformities in 1983 (CD method). The authors report on the application of the CD method for the treatment of IS from 1991 to date. After the operation of 36 patients they give an account of good results and report on the modifications of the surgical technique on the basis of their experiences. Aware of the late consequences of the surgical treatment of IS the authors started with the investigation of the aetiology of the disease in order to introduce a causal treatment. As for the aetiological background of IS, data on the role of heritable factors were relevant only. They gave a hint to start with studies aimed at the investigation of genetic determinants of the syndrome. I aberration of chromosome #10 [karyotype: inv(10)(p11q26)]. In one of the cases there was a multiple familial occurrence of the syndrome coupled with the same anomaly of the karyotype. The probands' father and grandfather all had the same pattern of scoliotic deformity and the same aberrant karyotype of chromosome #10 was found both in the proband and his father. Preparation of genomial DNA from peripheral blood of the patients was started. Fragment length polymorphism (RFLP) examination with PCR technique using oligonucleotide primers specific for chromosome #10 and for regulatory genes of left-right body assymetry is underway.

Chromosome Aberrations↗

Surgical sperm retrieval for intracytoplasmic sperm injection.

The introduction of intracytoplasmic sperm injection (ICSI) provides new hope for many couples suffering from the most untreatable forms of male infertility as ICSI can also be successfully performed using epididymal or testicular spermatozoa. Testicular spermatozoa may be recovered from testicular tissue in every patient with excretory azoospermia, but also in about half of patients with secretory azoospermia. The strongest parameter to predict successful testicular sperm recovery is histopathological examination of a testicular biopsy, especially in patients with some form of germ-cell aplasia. Even in our series of Klinefelter patients, testicular sperm were recovered in eight out of 15 patients and after seven ICSI cycles combined with preimplantation diagnosis, two singletons were born. Less invasive techniques such as percutaneous fine-needle aspiration have been introduced and may yield comparable success rates in patients with normal testicular function. The high fertilization rates after testicular sperm recovery and ICSI and the favourable implantation rates may therefore render microsurgical epididymal sperm aspiration (MESA) obsolete in the future for patients with normal spermatogenesis. Besides, the use of cryopreserved testicular spermatozoa may become an alternative to repeated surgery for obtaining testicular tissue for subsequent ICSI treatment cycles.

Epididymis↗

[Effect of fibroscopic sclerotherapy of hemorrhaging esophageal varices on survival in alcoholic liver cirrhosis (comparative retrospective study)].

UNLABELLED: Between 1983 and 1992 altogether 638 alcoholic cirrhotic patients had been treated because of acute esophageal variceal bleeding. In 96 cases the treatment were carried out in the following circumstances; volume and coagulation factor substituate, vasopressin or glypressin and nitroglycerin, urgent endoscopy and ballontamponade but in 47 cases an urgent sclerotherapy were also performed. The survival, cases of rebleeding,-from the first bleeding events-of the 49 nonsclerosed patients were compared to those of the 47 sclerosed one. CONCLUSIONS: 1. The endoscopic sclerotherapy proved to be life-saving procedure. 2. Within 30 days the nonsclerosed patients died twice as much number than the slcerosed patients. 3. The lengths of the survival period were found four and half times so long at the sclerosed patients than in nonsclerosed patients (535 versus 125 days). 4. The numbers of the rebleeding were not less at the sclerosed patients than the nonsclerosed subjects. 5. The lengths of the nonbleeding period was found triple so long at the sclerosed patients than in nonsclerosed patients. 6. The survival of the "Child C" patients at the sclerosed and nonsclerosed patients, too. The authors come to conclusion that by the fiberendoscopic sclerotherapy an increase in the survival time of the patients with acute esophageal variceal bleeding in alcoholic cirrhosis can be achieved.

Acute Disease↗

[HIV infection es IgA nephropathy].

Similar immunological abnormalities exist in IgA nephropathy and HIV infection and several IgA nephropathy cases were reported in HIV-infected patients. To estimate the number of HIV-infected patients in IgA nephropathy, 80 patients with IgA nephropathy were studied for HIV-1 and HIV-2 antibody seropositivity. Although they failed to detect HIV positivity among their IgA nephropathy patients, because of the increasing number of people are being infected with HIV, the screening of IgA nephropathy patients for HIV infection would warrant.

AIDS-Associated Nephropathy↗

Normal pregnancies resulting from testicular sperm extraction and intracytoplasmic sperm injection for azoospermia due to maturation arrest.

OBJECTIVE: To see whether testicular sperm extraction could be used to perform intracytoplasmic sperm injection (ICSI) for men with nonobstructive azoospermia caused by maturation arrest. DESIGN: Uncontrolled prospective trial of an attempt to find occasional elongated spermatids or spermatozoa in testes of azoospermic patients with maturation arrest and to use these haploid cells for ICSI. SETTING: European university-based center for reproductive medicine and private American community hospital. PATIENTS: Thirty-eight azoospermic males without obstruction and with biopsy-documented maturation arrest, seven of whom elected, with their wives, to undergo scrotal exploration and testicular sperm extraction with ICSI in an attempt to become pregnant. INTERVENTIONS: Histologic evaluation of spermatid development in 38 patients with azoospermic maturation arrest. Testicular sperm extraction with ICSI in seven random volunteers from this group. MAIN OUTCOME MEASURES: Presence or absence of mature spermatids in the testis biopsy specimen of patients with azoospermic maturation arrest. Fertilization, cleavage, and pregnancy after testicular sperm extraction and ICSI in patients with azoospermic maturation arrest. RESULTS: All seven patients with azoospermic maturation arrest had occasional sperm found with testicular sperm extraction. Five had sufficient numbers (between 6 and 30) for ICSI, and those five had ETs. In four, the partners became pregnant. In all 38 patients examined, the maturation defect was in meiosis rather than in spermiogenesis. CONCLUSION: Nonobstructive azoospermia caused by maturation arrest may be treated with testicular sperm extraction with ICSI apparently as successfully as Sertoli cell only.

Cellular Senescence↗

The use of testicular sperm for intracytoplasmic sperm injection in patients with necrozoospermia.

OBJECTIVE: To investigate whether intracytoplasmic sperm injection (ICSI) using testicular spermatozoa from necrozoospermic patients results in acceptable fertilization and transfer rates. DESIGN: Retrospective clinical study. SETTING: Tertiary referral center. PATIENTS: Five patients presenting consistently with 100% dead spermatozoa in their ejaculates. INTERVENTIONS: In seven treatment cycles, an open testicular biopsy was performed to increase the chances for retrieving viable spermatozoa which were used for ICSI. MAIN OUTCOME MEASURES: Sperm recovery, fertilization, and transfer rates. RESULTS: Testicular sperm were recovered in all treatment cycles and fertilization occurred in six of seven cycles. Overall normal fertilization and transfer rates were 67% and 71%, respectively. One live birth was obtained after five ETs. CONCLUSION: We recommend testicular sperm recovery for ICSI in patients who invariably or occasionally present with absolute necrozoospermia.

Adult↗