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131.
Foxl2 disruption causes mouse ovarian failure by pervasive blockage of follicle development 总被引:6,自引:0,他引:6
Uda M Ottolenghi C Crisponi L Garcia JE Deiana M Kimber W Forabosco A Cao A Schlessinger D Pilia G 《Human molecular genetics》2004,13(11):1171-1181
FOXL2 mutations cause gonadal dysgenesis or premature ovarian failure (POF) in women, as well as eyelid/forehead dysmorphology in both sexes (the 'blepharophimosis-ptosis-epicanthus inversus syndrome', BPES). Here we report that mice lacking Foxl2 recapitulate relevant features of human BPES: males and females are small and show distinctive craniofacial morphology with upper eyelids absent. Furthermore, in mice as in humans, sterility is confined to females. Features of Foxl2 null animals point toward a new mechanism of POF, with all major somatic cell lineages failing to develop around growing oocytes from the time of primordial follicle formation. Foxl2 disruption thus provides a model for histogenesis and reproductive competence of the ovary. 相似文献
132.
Kulesh DA Loveless BM Norwood D Garrison J Whitehouse CA Hartmann C Mucker E Miller D Wasieloski LP Huggins J Huhn G Miser LL Imig C Martinez M Larsen T Rossi CA Ludwig GV 《Laboratory investigation; a journal of technical methods and pathology》2004,84(9):1200-1208
During the summer of 2003, an outbreak of human monkeypox occurred in the Midwest region of the United States. In all, 52 rodents suspected of being infected with monkeypox virus were collected from an exotic pet dealer and from private homes. The rodents were euthanized and submitted for testing to the United States Army Medical Research Institute of Infectious Diseases by the Galesburg Animal Disease Laboratory, Illinois Department of Agriculture. The rodent tissue samples were appropriately processed and then tested by using an integrated approach involving real-time polymerase chain reaction (PCR) assays, an antigen-detection immunoassay, and virus culture. We designed and extensively tested two specific real-time PCR assays for rapidly detecting monkeypox virus DNA using the Vaccinia virus F3L and N3R genes as targets. The assays were validated against panels of orthopox viral and miscellaneous bacterial DNAs. A pan-orthopox electrochemiluminescence (ECL) assay was used to further confirm the presence of Orthopoxvirus infection of the rodents. Seven of 12 (58%) animals (seven of 52 (15%) of all animals) tested positive in both monkeypox-specific PCR assays and two additional pan-orthopox PCR assays (in at least one tissue). The ECL results showed varying degrees of agreement with PCR. One hamster and three gerbils were positive by both PCR and ECL for all tissues tested. In addition, we attempted to verify the presence of monkeypox virus by culture on multiple cell lines, by immunohistology, and by electron microscopy, with negative results. Sequencing the PCR products from the samples indicated 100% identity with monkeypox virus strain Zaire-96-I-16 (a human isolate from the Congo). These real-time PCR and ECL assays represent a significant addition to the battery of tests for the detection of various orthopoxviruses. In light of the recent monkeypox virus transmissions, early detection of the virus is crucial for both natural outbreaks and potential acts of bioterrorism. 相似文献
133.
Dieye TN Vereecken C Diallo AA Ondoa P Diaw PA Camara M Karam F Mboup S Kestens L 《Journal of acquired immune deficiency syndromes (1999)》2005,39(1):32-37
Flow cytometry is an accurate but expensive method to determine absolute CD4 cell counts. We compared different methods to measure absolute CD4 counts in blood samples from HIV-infected and uninfected subjects using a research/clinical flow cytometer (FACScan); a dedicated clinical instrument (FACSCount); and a volumetric, mobile, open-system flow cytometer equipped with 3 fluorescence and 2 light scatter detectors (Cyflow SL blue). The FACScan and Cyflow were used as single-platform instruments, but they differ in running cost, which is a central factor for resource-poor settings. Direct volumetric and bead-based CD4 measurements on the Cyflow were compared with 2 bead-based single-platform CD4 measurements on the FACSCount and on FACScan (TruCount) in "Le Dantec" Hospital, Dakar, Senegal, using whole blood samples from 102 HIV+ and 28 HIV- subjects. The agreement between the various measurement methods was evaluated by Bland-Altman analysis. Volumetric CD4 measurements on the Cyflow using a no-lyse-no-wash (NLNW) procedure and a lyse-no-wash (LNW) procedure correlated well with each other (R2 = 0.98) and with CD4 measurements on the FACSCount (R2 = 0.97) and FACScan (R2 = 0.97), respectively. Red blood cell lysis had no negative effect on the accuracy of absolute CD4 counting on the Cyflow. An excellent correlation was observed between bead-based CD4 measurements on the Cyflow and CD4 measurements on the FACSCount (R2 = 0.99) and FACScan (R2 = 0.99). Rigid internal and external quality control monitoring and adequate training of technicians were considered essential to generate accurate volumetric CD4 measurements on the Cyflow. 相似文献
134.
Mahadevan Mani S.; Amemiya Chris; Jansen Gert; Sabourin Luc; Baird Stephen; Neville Catherine E.; Wormskamp Nicole; Segers Bart; Batzer Mark; Lamerdin Jane; de Jong Peter; Wieringa Be; Korneluk Robert G. 《Human molecular genetics》1993,2(3):299-304
The mutation causing myotonic dystrophy (DM) has recently beenidentified as an unstable CTG trinucleotide repeat located inthe 3' untranslated region of a gene encoding for a proteinwith putative serine-threonine protein kinase activity. In thisreport we present the genomic sequences of the human and murineDM kinase gene. A comparison of these sequences with each otherand with known cDNA sequences from both species, led us to predicta translation initiation codon, as well as determine the organizationof the DM kinase gene. Several polymorphisms within the humanDM kinase gene have been identified, and PCR assays to detecttwo of these are described. The complete sequence and characterizationof the structure of the DM kinase gene, as well as the identificationof novel polymorphisms within the gene, represent an importantstep in a further understanding of the genetics of myotonicdystrophy and the molecular biology of the gene. 相似文献
135.
Paola Dal Cin Chris De Wolf-Peeters Magdy S. Aly Georges Deneffe Walter Van Mieghem Herman Van Den Berghe 《Genes, chromosomes & cancer》1993,6(4):243-244
Cytogenetic analysis of a thymoma showed the presence of a ring chromosome 6 as the sole chromosome abnormality. © 1993 Wiley-Liss, Inc. 相似文献
136.
Gregory CM Williams RH Vandenborne K Dudley GA 《European journal of applied physiology》2005,95(4):276-282
Characteristics of skeletal muscle such as fiber type composition and activities of key metabolic enzymes have been purported
to affect glycogen utilization. However, the relative importance individual factors may have in predicting glycogen utilization
of individual muscle fibers has not been addressed. Thus, we sought to determine the relative importance that metabolic characteristics
and phenotypic expression of individual fibers have in predicting fiber specific glycogen utilization during neuromuscular
electrical stimulation (NMES) exercise. Biopsies were taken from the m, vastus lateralis (VL) of eight recreationally active males before and immediately after 30 min of non-fatiguing NMES and
analyzed for type (I, IIa and IIx), succinate dehydrogenase activity (SDH), glycerol-phosphate dehydrogenase activity (GPDH),
quantitative-actomyosin adenosine triphosphatase activity (qATPase), and glycogen content. Our results demonstrate that a
ratio of enzyme activities representing pathways for energy supply and energy demand (SDH: qATPase) accounted for more of
the variance in glycogen utilization (y=0.2091 e−0.0329x
, R
2=0.622, P≤ 0.0001) than SDH (R
2=0.321) or qATPase (R
2=0.365) alone. Fiber phenotype was also a significant predictor of glycogen utilization, but to a lesser extent than the other
variables studied (R
2=0.201). A ratio of the activities of enzymes representing pathways of energy supply and energy demand, represented by SDH:qATPase,
is a better predictor of glycogen utilization than either of its components independently while fiber phenotype, although
a statistically significant predictor of glycogen utilization, may not be the most appropriate determinate of the functional
characteristics of an individual fiber. 相似文献
137.
Rats were permanently hypodipsic when offered a quinine adulterated fluid on a chronic basis. Plasma osmolarity and Na concentration were normal, but the quinine drinkers showed a slight hyperkalemia compared to water drinking controls. The quinine-drinking rats maintained hydromineral equilibrium through the excretion of a small amount of concentrated urine. The quinine intake was closely matched to need, and fell to near zero when food was removed or water was supplied intravenously. This harmony of intake and output was disrupted after acute hypertonic NaCl load: while the obligatory salt diuresis was no different between water and quinine drinkers, the latter did not drink (except at the lowest level of adulteration) within several hours. However, by 24 hr all had shown a delayed drinking response. This delay in drinking of quinine was also evident after non-painful intravenous NaCl infusions, but no drinking occurred after nephrectomy. Quinine drinkers were also unresponsive to isoproterenol and intracranial dipsogens. These data are discussed in terms of their implication for definitions of regulatory drinking behavior. 相似文献
138.
139.
Taylor Rachel R.; Egan Andrea; McGuinness David; Jepson Annette; Adair Richard; Drakely Chris; Riley Eleanor 《International immunology》1996,8(6):905-915
Malaria infection induces the production of serum antibodiesto a variety of malaria antigens but the prevalence of antibodiesto any particular antigen ins typically mucb less than 100%.It has been assumed that non-responsiveness to defined antigensin malaria immune subjects is due to HLA mediated restricutionof the Immune response. In this study we have investigated therole of HLA and non-HLA genes in the antibody response to twomerozoite surface antigens (MSP1 and MSP2) and a sexual stageantigen (Pfs260/230) opf P{lasmodium falcpartum, and concludethat host genotype is not a major determinant of responsiveness.Although antibody levels vary in accordance with seasonal variationsin malaria transmission in semi-immune children, antibiody levelsremain stable in clncall immine adults. 相似文献
140.