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11.
Detection of chromosomes and estimation of aneuploidy in human spermatozoa using fluorescence in-situ hybridization 总被引:11,自引:0,他引:11
The development and application of fluorescence in-situ hybridization
(FISH) has opened the way for comprehensive studies on numerical chromosome
abnormalities in human spermatozoa. FISH can be rapidly applied to large
numbers of spermatozoa and thus overcomes the major limitation of
karyotyping spermatozoa after penetration of zona-free hamster oocytes. The
simultaneous hybridization of two or more chromosome-specific probes to
spermatozoa and subsequent detection of the bound probes using different
fluorescent detection systems enables two or more chromosomes to be
localized simultaneously in the same spermatozoon and provides a technique
for undertaking reasonable estimates of aneuploidy. The most commonly used
probes are those which bind to the centromeric region of specific
chromosomes. Most studies to date have concentrated on estimating
aneuploidy in spermatozoa from normospermic men, although reports are
beginning to appear on aneuploidy in spermatozoa from subfertile and
infertile men. Multi- probe FISH studies have generally reported disomy
(hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary
evidence that some chromosomes such as X, Y and 21 are predisposed towards
higher rates of non-disjunction during spermatogenesis. There are also
suggestions of inter-donor variability in aneuploidy frequencies for
specific chromosomes, although this requires confirmation in larger
studies. While FISH is clearly a powerful technique that has many
applications in reproductive medicine, it must also be realized that it
does have limitations and the technology itself is still evolving and has
yet to be fully validated on spermatozoa.
相似文献
12.
Vaughan JR; Farrer MJ; Wszolek ZK; Gasser T; Durr A; Agid Y; Bonifati V; DeMichele G; Volpe G; Lincoln S; Breteler M; Meco G; Brice A; Marsden CD; Hardy J; Wood NW 《Human molecular genetics》1998,7(4):751-753
A mutation in exon 4 of the human alpha-synuclein gene was reported
recently in four families with autosomal dominant Parkinson's disease (PD).
In order to examine whether mutations in this exon or elsewhere in the gene
are common in familial PD, all seven exons of the alpha- synuclein gene
were amplified by PCR from index cases of 30 European and American
Caucasian kindreds affected with autosomal dominant PD. Each product was
sequenced directly and examined for mutations in the open reading frame. No
mutations were found in any of the samples examined. We conclude that the
A53T change described in the alpha- synuclein gene is a rare cause of PD or
may even be a rare variant. Mutations in the regulatory or intronic regions
of the gene were not excluded by this study.
相似文献
13.
Preliminary observations on polar body extrusion and pronuclear formation in human oocytes using time-lapse video cinematography 总被引:10,自引:17,他引:10
Payne D; Flaherty SP; Barry MF; Matthews CD 《Human reproduction (Oxford, England)》1997,12(3):532-541
In this study, we have used time-lapse video cinematography to study
fertilization in 50 human oocytes that had undergone intracytoplasmic sperm
injection (ICSI). Time-lapse recording commenced shortly after ICSI and
proceeded for 17-20 h. Oocytes were cultured in an environmental chamber
which was maintained under standard culture conditions. Overall, 38 oocytes
(76%) were fertilized normally, and the fertilization rate and embryo
quality were not significantly different from 487 sibling oocytes cultured
in a conventional incubator. Normal fertilization followed a defined course
of events, although the timing of these events varied markedly between
oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular
waves of granulation within the ooplasm which had a periodicity of 20-53
min. The sperm head decondensed during this granulation phase. The second
polar body was then extruded, and this was followed by the central
formation of the male pronucleus. The female pronucleus formed in the
cytoplasm adjacent to the second polar body at the same time as, or
slightly after, the male pronucleus, and was subsequently drawn towards the
male pronucleus until the two abutted. Both pronuclei then increased in
size, the nucleoli moved around within the pronuclei and some nucleoli
coalesced. During pronuclear growth, the organelles contracted from the
cortex towards the centre of the oocyte, leaving a clear cortical zone. The
oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during
the course of the observation period. The female pronucleus was
significantly smaller in diameter than the male pronucleus (24.1 and 22.4
microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0
respectively, P < 0.0001). After time-lapse recording, oocytes were
cultured for 48 h prior to embryo transfer or cryopreservation. Embryo
quality was related to fertilization events and periodicity of the
cytoplasmic wave, and it was found that good quality embryos arose from
oocytes that had more uniform timing from injection to pronuclear abuttal
and tended to have a longer cytoplasmic wave. In conclusion, we have shown
that time-lapse video cinematography is an excellent tool for studying
fertilization and early embryo development, and have demonstrated that
human fertilization comprises numerous complex dynamic events.
相似文献
14.
Variance in rotavirus infection rates in different urban population groups in South Africa 总被引:2,自引:0,他引:2
B D Schoub F Cohen D Thompson H J Koornhof M D Miliotis C S Still F E Berkowitz S Miller E Kushlick 《Journal of medical virology》1982,10(3):171-179
Rotavirus infection in black infants contrasts markedly with that of white infants in being much less common and showing no seasonal variation. In this multicentre study in Johannesburg, the aetiology of winter infantile gastroenteritis in black, coloured, and white infants was investigated. Stools were examined by electron microscopy and also by enzyme-immunoassay to detect subparticular antigen which may be missed by electron microscopy in patients presenting late in the course of the illness. Stools were also examined bacteriologically by conventional techniques. Rotavirus was the most common pathogen in all three population groups with bacteria playing a relatively minor role. Striking differences were observed in the rotavirus rates between the three groups. Infection in the whites was five times more common than in the blacks (60% versus 12%) with the coloureds intermediate at 40%. The hypothesis was put forward that the relative protection of the black population may be due to a greater degree of colonization of neonates, thus inducing protection against symptomatic infection at the target age of 6 to 24 months. This may well have important implications in immunoprophylaxis. The reason for the lack of seasonal variation in the black population is still unclear. 相似文献
15.
16.
María Jesús Fernández Aceñero MD PhD Cristina Díaz del Arco CDdA MD Carme Dinarés CD MD PhD Tania Labiano TL MD Eva Tejerina ET MD PhD Mª José Bernabé MJ B MD Elena Forcen EF MD Melchor Saiz-Pardo MSP MD Pablo Pérez PP MD Maria D. Lozano MDL MD PhD 《Diagnostic cytopathology》2023,51(1):26-35
Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples. 相似文献
17.
Bowerbank CR Smith PA Drown DB Alexander W Jederberg WW Still KR Lee ML 《Drug and chemical toxicology》1999,22(1):57-71
Solvating gas chromatography (SGC) involves a mobile phase that is a supercritical fluid at the column inlet (typically 100-350 atm) and a gas upon exiting the column at ambient pressure. SGC has characteristics of both supercritical fluid chromatography and gas chromatography, and may be adaptable to a system with characteristics approaching a "universal chromatograph" capable of analyzing many classes of compounds on one instrument. We have recently found that using a solvating mobile phase such as CO2, together with small, spherical particle-packed capillary columns can offer significant advantages for rapid chemical analysis. A need exists in operational military settings to rapidly detect a wide range of chemicals with potential adverse health effects for exposed personnel. A separation step improves analytical capability by reducing or eliminating chemical background for better detection limits, and purifies or isolates target analytes and unknowns for improved identification. SGC, coupled to a high volume vapor/aerosol sampler and a rapid mass spectrometric detector such as a time-of-flight mass spectrometer could provide rapid, positive identification of separated compounds, with the resulting chromatographic and mass spectral data stored in digital format for future retrieval. Such a system will significantly advance the ability of military commanders to detect airborne chemical agents rapidly and accurately, protecting the health of military personnel. 相似文献
18.
A simple auto-evaluation sheet is presented for the proper assessment of the patient's condition after surgery. Stress is
put not only on weight loss, but on other important factors as well. 相似文献
19.
20.
Early excision of burn eschar and wound closure significantly improves survival following major burn injury. Immediate primary excision performed by burn-experienced surgeons in dedicated burn care facilities can reduce further morbidity and mortality, length of hospital stay and medical costs. Burn care at the millennium is evolving rapidly into a subcategory of trauma surgery, with burn patients increasingly being viewed as victims of major trauma who benefit most from immediate and definitive surgical correction of their injuries. 相似文献