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71.
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
72.
P Manu D A Matthews T J Lane H Tennen V Hesselbrock R Mendola G Affleck 《Journal of affective disorders》1989,17(2):165-172
The prevalence of mood disorders among patients with chronic fatigue was examined in a group of 100 adults who had experienced fatigue symptoms for an average of 13 years. Patients received a comprehensive history, physical and laboratory evaluation and completed the National Institute of Mental Health Diagnostic Interview Schedule and the Beck Depression Inventory (BDI). Among 44 patients with depressive illness, the onset of their first depressive episode was strongly associated with and preceded the onset of chronic fatigue. The BDI, fatigue history, demographic factors, and findings from the physical examination and laboratory had only modest success in discriminating those patients with depressive illness from other patients. We conclude that depressive illness is an important precursor of chronic fatigue. 相似文献
73.
J. B. Matthews A. Pitigala-Arachchi I. J. Crane C. Scully S. S. Prime 《Virchows Archiv : an international journal of pathology》1988,413(6):521-528
Summary The development of oral epithelial expression of Ia antigens and its relationship to the presence of IL-2r+ (CD25+) cells was investigated in rats treated with the water soluble carcinogen 4-nitroquinoline-N-oxide (4NQO). Acetone fixed frozen sections of the palate and tongue were stained using an indirect immunoperoxidase technique and monoclonal antibodies to rat Ia (I-A & I-E) and IL-2 receptor. After 4 weeks 4NQO treatment all rats expressed oral epithelial Ia but thereafter (2–9 months) expression was present in only 20–40% of animals. Epithelial expression of Ia by histologically normal, dysplastic and neoplastic epithelium was always associated with the presence of an underlying inflammatory cell infiltrate containing CD25+ cells. Overall there were significantly more CD25+ cells in tissue specimens containing Ia+ epithelium compared with Ia– epithelium. Furthermore, during the first 4 weeks of carcinogen treatment, a significant positive correlation was found between the CD25+ cell density and occurrence of focal epithelial Ia expression. These results, together with analysis of the T cell, NK cell, macrophage and B cell content of the infiltrates induced by 4NQO, suggest that the CD25+ cells represent activated T cells. Thus, our results in this experimental model are consistent with the idea that epithelial expression of Ia is the result of production of IFN- by locally activated T cells. 相似文献
74.
75.
Benjamin Pelletier Audrey Perrin Noémie Assoun Camille Plaquet Nathalie Oreal Laetitia Gaulme Adeline Bouzereau Jean-Louis Labernardière Mélanie Ligouis Vincent Dioszeghy Sophie Wavrin Katie Matthews Fabrice Porcheray Hugh A. Sampson Pierre-Louis Hervé 《Allergy》2021,76(4):1213-1222
Background
The prevalence of tree nut allergy has increased worldwide, and cashew has become one of the most common food allergens. More critically, cashew allergy is frequently associated with severe anaphylaxis. Despite the high medical need, no approved treatment is available and strict avoidance and preparedness for prompt treatment of allergic reactions are considered dual standard of care. In the meantime, Phase III study results suggest investigational epicutaneous immunotherapy (EPIT) may be a relevant and safe treatment for peanut allergy and may improve the quality of life for many peanut allergic children.Objective
We aimed to evaluate the capacity of EPIT to provide protection against cashew-induced anaphylaxis in a relevant mouse model.Methods
The efficacy of EPIT was evaluated by applying patches containing cashew allergens to cashew-sensitized mice. As negative control, sham mice received patches containing excipient. Following treatment, mice were challenged orally to cashew and anaphylactic symptoms, as well as plasmatic levels of mast-cell proteases (mMCP)-1/7, were quantified.Results
Of 16 weeks of EPIT significantly protects against anaphylaxis by promoting a faster recovery of challenged mice. This protection was characterized by a significant reduction of temperature drop and clinical symptoms, 60 minutes after challenge. This was associated with a decrease in mast-cell reactivity as attested by the reduction of mMCP-1/7 in plasma, suggesting that EPIT specifically decrease IgE-mediated anaphylaxis.Conclusion
We demonstrate that EPIT markedly reduced IgE-mediated allergic reactions in a mouse model of cashew allergy, which suggests that EPIT may be a relevant approach to treating cashew allergy.76.
The immunoglobulin nature of Russell bodies 总被引:2,自引:0,他引:2
J B Matthews 《British journal of experimental pathology》1983,64(3):331-335
Although Russell bodies have been widely regarded as aggregates of immunoglobulin (Ig) their true nature remains controversial. This report reinvestigates the Ig reactivity of Russell bodies using an immunoperoxidase technique to detect IgG, IgA, IgM, kappa and lambda light chains and J chain on formalin fixed paraffin embedded tissue. Both intracellular and extracellular Russell bodies stained for Ig heavy and light chain determinants. Generally staining was most intense at the surface of these structures although many appeared to have detectable Ig determinants within the Russell body cores. The results suggest that Russell bodies, irrespective of size or site, are associated with intact Ig molecules. 相似文献
77.
The histology of gonadotropin-secreting bronchogenic carcinoma 总被引:1,自引:0,他引:1
J C Cottrell K L Becker M J Matthews C Moore 《American journal of clinical pathology》1969,52(6):720-725
78.
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
79.
80.
Nuclei of the medial septum/diagonal band region of the mammalian forebrain contain neurons that give rise to the septohippocampal pathway, which has separate cholinergic and GABAergic components. This pathway is known to influence hippocampal-dependent memory and learning processes, but the precise role of each component is unclear. In this study, we tested the hypothesis that fast-firing, non-bursting medial septum/diagonal band neurons are GABAergic. We used brain slice preparations from young adult guinea-pigs and rats, or from weanling rats, to perform current-clamp recordings from medial septum/diagonal band neurons. Recorded neurons were injected with biocytin for subsequent visualization with fluorescent avidin, and then hybridized with a 35S-labeled riboprobe for glutamate decarboxylase-67 messenger RNA. As a positive control, guinea-pig cerebellar Purkinje cells were labeled and hybridized with the riboprobe. As expected, labeled Purkinje cells were glutamate decarboxylase-67 messenger RNA positive. Slow-firing, cholinergic (choline acetyltransferase-positive) guinea-pig medial septum/diagonal band neurons were glutamate decarboxylase-67 messenger RNA negative. Contrary to our hypothesis, of the guinea-pig neurons, only three of 11 fast-firing neurons were glutamate decarboxylase-67 positive. Of the rat medial septum/diagonal band neurons, three of four were positive for glutamate decarboxylase-67 messenger RNA.These data suggest that fast-firing, non-bursting neurons of the medial septum/diagonal band, as sampled by sharp-electrode intracellular recordings in brain slices, may be a heterogeneous group of neurons, some of which are GABAergic. Together with recent data demonstrating the presence of another GABAergic marker, parvalbumin, in fast-firing septal neurons, we conclude that GABAergic septohippocampal neurons include a population of fast-firing, non-bursting neurons. The influence of these neurons on the hippocampus is likely to occur on a shorter time-scale and over a wider range of firing frequencies as compared to slowly firing cholinergic septohippocampal neurons. 相似文献