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Tétel Szabadon hozzáférhető Az uterus didelphys szülészeti jelentősége(2000) Csorba, Roland; Major, Tamás; Csenke, Péter; Borsos, AntalTétel Szabadon hozzáférhető Granulocyták szuperoxid-anion termelése endometrium carcinoma felismerésekor és kezelés után(1999) Póka, Róbert; Szűcs, Sándor; Ádány, Róza; Szikszay, Edit; Borsos, AntalTétel Szabadon hozzáférhető Gyermekekkel szembeni szexuális erőszak a családban(2002) Csorba, Roland; Borsos, AntalTétel Szabadon hozzáférhető Gyermeknőgyógyászati betegek hüvelyaspirátumának onkocitológiai vizsgálata során szerzett tapasztalataink.(1981) Hernádi, Zoltán; Borsos, AntalTétel Szabadon hozzáférhető Indokolt-e a profilaktikus ovariektomia?(1977) Hernádi, Zoltán; Borsos, Antal; Lampé, LászlóTétel Szabadon hozzáférhető Petefészekrákos betegek cyclophosphamide és cisplatin (CP) kombinált kemoterápiája Amifostine (WR-1065) védelmében(1998) Hernádi, Zoltán; Lukácskó, Lóránd; Sápy, Tamás; Borsos, AntalTétel Korlátozottan hozzáférhető Relationship Among Attributes of Sperm Immaturaty, Chromosomal Non Disjunction -Results by Double Probing of Individual Spermatozoon(2009-11-05T08:34:09Z) Óvári, László; Borsos, Antal; Klinikai orvostudományok doktori iskola; DE--OEC--Általános Orvostudományi Kar --Biochemical markers are reliable indicators of sperm maturity and function. The major hallmark among biochemical markers is the 70 kDa heat shock protein, the HspA2. It proved to be very useful in assessment of sperm immaturity and fertilization potential. Expression of HspA2 is developmentally regulated, having a characteristic dual wave expression pattern. The first peak is in the round spermatocytes, the second a major peak is expressed in the elongating spermatids. Concerning the function of HspA2, it is part of the synaptonemal complex and supports the meiosis in round spermatocytes; abnormal expression therefore may cause meiosis defects, disomies. In the elongation phase HspA2 as chaperone protein facilitates assembly, folding and transport of different proteins among them protamins, DNA repair enzymes and proteins necessary for membrane remodeling. The low expression of HspA2 resulted in different forms of arrested nuclear and cytoplasmic maturities, like persistent histones, DNA chain brakes and surplus cytoplasm. Previous studies on HspA2 theory found correlation between different attributes of cellular immaturity in the semen samples. Other researches studied relationship between meiotic defects and various cellular immaturity forms in semen samples, and there was also strong correlation between them. These studies validate the HspA2 theory, but the intracellular relationship between the HspA2 related defects remained unclear. My concern in this thesis was to find intracellular correlation between different HspA2 related defects such as nuclear and cellular immaturity attributes and meiotic nondisjunction. To test supposed co-occurrence of abnormalities double probing technique of individual spermatozoa has been developed. In the first experiment by consecutive AB and FISH probing we found that arrested nucleoprotein replacement and meiotic non disjunction are related within individual spermatozoa. This study validates our hypothesis on the central role of HspA2 in the spermatogenesis. In another study AB staining was combined with CK immunostaining, ISNT, and caspase-3 immunocytochemistry. Data of this study proved that different attributes of arrested maturity in the nuclear and cellular compartment, persistent histones, surplus cytoplasm and DNA chain bakes are related in the same cell, moreover the degree of abnormalities were also conforming (kappa=0.8). The apoptotic activity was also related to immaturity. These facts support the theory that HspA2 has central role in the spermatogenesis. However in low proportion there is heterogeneity in staining pattern. This is important for two reasons; first it proves that sperm after the defected maturation step may follow its changes in several pathways. Second the arrested spermiogenesis can not be examined correctly just by one biochemical probe only. In the third study detailed morphometrical evaluation of the sperm head and tail was carried out in order to find differences between native, non decondensed spermatozoa with haploid and disomic set. Meanwhile there was significant difference in morphometric parameters such as head area, head area and the short axis between haploid and aneuploid cells by objective morphometry, disomic sperm heads were larger, but the by evaluation of distribution data were inconsistent, there was also a substantial (70%) overlapping in the of the values of these two populations, and disomic sperm heads were among the microcephalic spermatozoa also. Our data proves that the visual assessment in the selection of good chromosomal quality sperm using morphometric aspects is unreliable. -----Tétel Szabadon hozzáférhető Sperm selection for human assisted reproduction(2007-07-19T12:01:01Z) Jakab, Attila; Borsos, Antal; DE -- Orvos- és Egészségtudományi Centrum -- Általános Orvostudományi Kar -- Szülészeti és Nőgyógyászati Klinika; Klinikai orvostudományok doktori iskolaWith the advent of modern assisted reproduction techniques, especially with the intracytoplasmic sperm injection (ICSI) effective treatment has become available for men with severe male infertility. ICSI is efficiently used in clinical practice, but unfortunately, as a result of intensive research an increased risk of transmission of cytogenetic defects to the offspring has also been documented. With the cytogenetic studies of semen from 32 infertile men, we documented, that in oligospermic patients who are candidates for ICSI, there is an increased frequency of sperm with sex chromosome aneuploidy, especially the XY disomy. Further, the diploidy frequency is increased in oligozooastenospermic samples. Defective chromosome separation of either meiosis I. or meiosis II. can be responsible for the production of diploid spermatozoa, but in patients with low sperm count the failure of the nuclear cleavage during meiosis II. seems to be responsible to the elevated diploidy frequency. Conventional WHO parameters of semen analysis (sperm count and motility) do not correlate with the frequency of numerical chromosomal anomalies. The risk can be determined using fluorescence in-situ hybridization (FISH) on decondensed spermatozoa. Due to the elevated risk of transmission of genetic disorders to the offspring with ICSI, there is a need to eliminate spermatozoa with numerical chromosomal anomalies before assisted fertilization. With the FISH examination of over 470,000 sperm from 44 donors we established, that presently used sperm preparation techniques (the gradient centrifugation and swim-up) are not sufficiently effective in eliminating both aneuploid and diploid sperm. The gradient centrifugation effectively decreases the frequency of immature and aneuploid sperm, while the swim-up preparation is able to reduce significantly the diploid sperm due to their defective motility. There is a correlation between the rate of immature sperm and aneuploidy frequency, but no relationship seems to exist among sperm motility and aneuploidy. Also, selecting sperm for ICSI, based on shape properties alone, does not preclude the presence of chromosomal abnormalities, particularly disomies. Using objective morphometry and FISH on the same sperm we gave evidence, that sperm with chromosomal aberrations may occur among normal spermatozoa. We developed a sperm selection method based on the membrane properties and hyaluronic acid binding capacity of mature spermatozoa. Only mature sperm with low aneuploidy/diploidy frequencies are able to bind the solid state hyalunonan. Sperm selection with our experimental method may provide a new, safe and efficient solution for selection of individual mature sperm for ICSI with very low risk of numerical chromosome abnormalities.Tétel Szabadon hozzáférhető Vákuum-extrakció szilikongumi-haranggal(1997) Póka, Róbert; Borsos, Antal