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T Nagy

Publications and source records attributed to T Nagy.

At least 37 records · Page 2Linked to original sources
PubMed1997

Hip-Arg-Phe-, Hip-Phe-Arg- and Hip-His-Leu-cleaving dipeptidyl carboxypeptidases in human adrenal tumors.

Hip-Arg-Phe-, Hip-Phe-Arg- and Hip-His-Leu-cleaving dipeptidyl carboxypeptidase activities were measured in the supernatant (S2) and pellet (P2) fractions obtained by ultracentrifugation of human adrenal tumor preparations. Negligible enzyme activity was found in cortical tumor whereas highly significant activities were present in the P2 fractions of the two pheochromocytoma specimens. The hydrolysis rates, expressed in terms of the percent of added substrate were 58-66%/60 min for Hip-Phe-Arg, 55-58%/60 min for Hip-Arg-Phe and 19-30%/60 min for Hip-His-Leu. The angiotensin-converting enzyme inhibitor, captopril, differentially inhibited the enzyme splitting Hip-His-Leu versus the one cleaving Hip-Arg-Phe; Hip-Phe-Arg is probably the substrate of both. It is concluded that the Hip-Arg-Phe-cleaving enzyme in adrenomedullary tumor is probably identical to the purportedly novel dipeptidyl carboxypeptidase that we detected earlier in rabbit ear artery wall, which converts (Met5)-enkephalin-Arg6,Phe7 to (Met5)-enkephalin.

Adrenal Gland Neoplasms↗
PubMed1997

Monoclonal antibodies for high-resolution localization of NHE3 in adult and neonatal rat kidney.

Previous immunochemical studies have shown that NHE3 is an apical Na+/H+ exchanger in some renal epithelia. The purpose of the present study was to develop high-affinity, isoform-specific monoclonal antibodies (MAbs) that would be useful for carrying out high-resolution immunocytochemical studies of NHE3 in the adult and neonatal mammalian kidney. Three MAbs were developed to a fusion protein containing amino acids 702-832 of rabbit NHE3. Specificity was established by immunoblotting membranes from NHE-deficient LAP cells that had been transfected with either NHE1,-2, -3, or -4. With the use of high-resolution immunocytochemical techniques, NHE3 was found in vesicles in the apical cytoplasm of proximal tubule cells, as well as in the apical plasma membrane of the proximal tubule, and in both the thin and thick limbs of the loop of Henle. When localized in the 1-day-old rat kidney, NHE3 was first detected in the late stages of the S-shaped body. In later stages of nephron development, the pattern of NHE3 staining was similar to that seen in the adult. This study demonstrates 1) the specificity of three MAbs for Na+/H+ exchanger isoform NHE3; 2) NHE3 is present in an intracellular vesicular compartment in cells of the proximal tubule, consistent with possible regulation by membrane recycling; and 3) NHE3 is expressed on the apical membrane in early stages of the developing nephron.

Aging↗
PubMed1996

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, genetic homogeneity, and mapping of the locus within a 2-cM interval.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a recently identified autosomal dominant cerebral arteriopathy characterized by the recurrence of subcortical infarcts leading to dementia. A genetic linkage analysis conducted in two large families recently allowed us to map the affected gene on chromosome 19 in a 12-cM interval bracketed by D19S221 and D19S215. In the present study, these first 2 families and 13 additional ones, including a total of 199 potentially informative meiosis, have been genotyped with eight polymorphic markers located between D19S221 and D19S215. All families were linked to chromosome 19. The highest combined lod score (Zmax = 37.24 at theta = .01) was obtained with marker D19S841, a new CAn microsatellite marker that we isolated from chromosome 19 cosmids. The recombinant events observed within these families were used to refine the genetic mapping of CADASIL within a 2-cM interval that is now bracketed by D19S226 and D19S199 on 19p13.1. These data strongly suggest the genetic homogeneity of this recently identified condition and establish the value of its clinical and neuroimaging diagnostic criteria. Besides their importance for the ongoing positional cloning of the CADASIL gene, these data help to refine the genetic mapping of CADASIL relative to familial hemiplegic migraine and hereditary paroxysmal cerebellar ataxia, conditions that we both mapped within the same chromosome 19 region.

Cerebral Arterial Diseases↗
PubMed1994

Inhibition of retinal regeneration in larval Rana by an antibody directed against a laminin-heparan sulfate proteoglycan.

In vivo and in vitro experiments have demonstrated that the retinal pigmented epithelium can give rise to neuronal precursors during retinal regeneration in amphibians. In vitro experiments have further demonstrated that this process is greatly facilitated by two molecules associated with basement membranes: laminin and fibroblast growth factor. We now report that retinal regeneration can be blocked in vivo by an antibody that inhibits the interaction of cells with the laminin-heparan sulfate proteoglycan complex. These results further support a role for the extracellular matrix in regulating cellular phenotype during retinal regeneration.

Animals↗
PubMed1992

[Surgical cerclage in the treatment of cervical incompetence during pregnancy (determining the legitimacy of the procedure)].

The authors studied the effectiveness of the cervical cerclage operation in the therapy of cervical insufficiency during the pregnancy. Two Hundred sixteen pregnant women took part in this trial in whose pregnancy the necessity of cerclage operation was not unequivocal. It means, that the therapeutical cerclage operation was not necessary, but the necessity of prophylactic cerclage operation was doubtful as well. From the randomized 216 cases they performed cerclage operation in 108 pregnancies and in 108 cases they did not perform it. In the respect of pregnancy care they did not make any difference between the two groups. The authors from their trial draw the conclusion, that in doubtful cases where the necessity of cervical cerclage operation is not unequivocal--e.g. at serious gestational case history--it is advisable to perform the operation. The danger of premature birth can be diminished in this way.

Female↗
PubMed1992

[Laparoscopic cholecystectomy. Initial experiences].

Between February 1991 and July 1991, 74 laparoscopic cholecystectomies were performed. The number of all cholecystectomies during this period was 168. Two surgeons performed the operations. Stone in the common bile duct, old age, acute cholecystitis, severe obesity and heart rhythm disorders were regarded as contraindications. The duration of the operation was 45-210 min. (mean 127 min). The intervention was diverted to open cholecystectomy in 2 instances (2.7%). Early postoperative complications were observed in 2 cases (2.7%): biliary discharge and bleeding. Reoperation was necessary in one patient (1.3%) because of bleeding. There was no operative mortality. The mean duration of hospitalization was 5.6 days, and the mean postoperative period was 2.7 days. It is considered that, laporoscopic cholecystectomy can be carried out only by specialists in both bile surgery and laparoscopic techniques, provided that all the personal and technical conditions necessary for traditional cholecystectomies are at hand. Both medically and economically, the laparoscopic cholecystectomy results attain or even exceed those of the traditional open technique.

Adult↗
PubMed1991

[Individual and average weight requirements of pharmaceutical preparations].

Authors studied the weight deviations allowed by non-statistically constructed individual and average weight requirements of Pharmacopoeas under consideration of normal Gaussian distribution. Normality was examined on a given suppository product and has been established, that in this case theoretically the hypothesis of normal distribution is not valid. For this reason deviation characteristics calculated according to the severest and the lightest Pharmacopoean requirements have been presented, i.e. the lower limit (if the deviation is less than this limit, the preparation meets the requirements by all means), and the upper limit (if the deviation is larger than this limit, the preparation definitively does not meet the requirements) respectively. Moreover, deviation characteristics calculated for continuous Gaussian distribution and for discrete distribution with few elements (representing a good approximation of the former) are given in the paper. On the basis of these results authors suggested to modernize the requirements of Pharmacopoeas and to continue research work in this direction.

Dosage Forms↗
PubMed1987

A possible role for the vascular membrane in retinal regeneration in Rana catesbienna tadpoles.

We have studied the process of retinal regeneration in Rana catesbienna tadpoles using a recently developed monoclonal antibody (2D3) directed against frog neurons and germinitive neuroepithelium. We have found that, following retinal degeneration induced by devascularization, new retina is generated in the posterior eye from transdifferentiating pigment epithelial (RPE) cells and in the anterior eye from increased proliferation at the normal growth zone in the ora serrata. This demonstrates that the anuran retina regenerates in a manner similar to that observed previously in urodeles. In addition, the use of MAb-2D3 has allowed us to study the process of RPE transdifferentiation more accurately than was previously possible, and consequently we have found a high degree of association of migratory pigment cells with the retinal vascular membrane at the time of the initial RPE transdifferentiation to retinal neuroblasts.

Animals↗
PubMed1983

The role of ischaemia in the formation of postoperative intra-abdominal adhesions.

The formation of intra-abdominal adhesions was studied in animal experiments. In dogs, the peritoneal lining was eliminated on the left side of the abdominal wall, while ischaemia was elicited contralaterally by suturing the main vessels. Two to seven weeks later no omental adhesion could be found on the abdominal wall deprived of peritoneum, while it developed in 11 of the 13 operated animals in the ischaemic area.

Abdominal Muscles↗
PubMed1982

[Late results of transduodenal sphincterotomy and sphincteroplasty based on 18 years of experience (with special respect to the analysis of unsatisfactory results) (author's transl)].

In the course of 18 years the authors performed transduodenal sphincterotomy on 289 and sphincteroplasty on 87 patients. The operations were connected, in 295 cases with primary in 81 cases with repeated biliary surgery. Twenty of the patients (5.3%) died during the immediate postoperative period. However, on the grounds of autopsy data the death of only 10 patients (2.6%) can be attributed to the surgery of the sphincter. Out of the 356 surviving patients 270 were available for a follow-up study and were examined 1-11 years after the operation. Late results of the operation were found excellent or good in 89.6% of the patients. To clear up the unsatisfactory results clinical, laboratory, radiological, and endoscopic examinations were carried out. The unsatisfactory results can be explained by biliopancreatic (6.6%), organic extrabiliary (0.7%) and non-organic (1.5%) reasons. The authors emphasize the significance of endoscopic examinations following the surgery of the sphincter in the elucidation of the causes of unsatisfactory results.

Ampulla of Vater↗
PubMed1981

[Important cause for reoperations of the common bile duct: papillary stenosis].

The authors have surveyed 94 cases of stenosis of Vater's papilla diagnosed in 270 late reoperations. In their opinion in more than one third of the cases stenosis of Vater's papilla persisted even at the time of the first surgical interference, only it was not diagnosed and adequately solved. They are convinced that by the routine use of radiomanometry, in addition to intraoperative close circuit TV monitoring, by the correct interpretation of the data and adequate surgery, the number of late reoperations after surgery of the biliary tract can be considerably decreased. The procedure has been in use at the author's clinic since 1961.

Adult↗
PubMed1981

[Experimental studies of circulation following a plication operation].

Three types of plications were performed on dogs: 1. modified mesenterial plication; 2. transjejunal internal splinting; 3. intestine duplication according to Noble. No passage disorder or abnormal circulation were observed; compared with the values of the control dogs isotope activity was the same after plication. Thus, there is no danger of impaired circulation after this type of operation.

Animals↗
PubMed1980

Acute water shortage and health problems in Haiti.

During a severe drought Port-au-Prince, Haiti, lost hydroelectric power for 10 weeks. This led to water shortages in areas of the city dependent on water supplied from electrically driven pumps. In a study of the impact of water restriction on disease, 400 families were randomly selected from two urban areas differentially affected by the water shortage. Disease in children was found to be related to quantity of water used, socioeconomic status, employment of head of household, and family size. The methods used in this study are recommended for the investigation of the relationship between water quantity and health.

Drinking↗