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51.
Diffuse leiomyomatosis is associated with the inherited kidney disease Alport syndrome, and characterized by visceral smooth muscle overgrowth within the respiratory, gastrointestinal and female reproductive tracts. Although partial deletions of the type IV collagen genes COL4A5 and COL4A6, paired head-to-head on chromosome Xq22, are known to cause diffuse leiomyomatosis, loss of function for type IV collagen does not explain smooth muscle overgrowth. To further clarify pathogenic mechanisms, we have characterized novel deletions in patients with Alport syndrome-diffuse leiomyomatosis or Alport syndrome alone. A 27.6-kb deletion, in a female with Alport syndrome-diffuse leiomyomatosis, is marked by the most proximal, i.e. most 5', COL4A5 breakpoint described to date. By comparing this deletion to others described here and previously, we have defined a minimal overlap region, only 4.2 kb in length and containing the COL4A5-COL4A6 proximal promoters, loss of which contributes to smooth muscle overgrowth. A novel deletion in a male with Alport syndrome alone is>1.4 Mb in length, encompassing COL4A5 and COL4A6 entirely, as well as neighboring genes. We postulate that loss of the 4.2-kb region in diffuse leiomyomatosis causes misregulation of neighboring genes, contributing to smooth muscle overgrowth. Deletion of the neighboring genes themselves may afford protection from this condition. 相似文献
52.
Rachel Rabin Yoel Hirsch Martin M. Johansson Joseph Ekstein David A. Zeevi Beth Keena Elaine H. Zackai John Pappas 《American journal of medical genetics. Part A》2019,179(10):2144-2151
Warsaw breakage syndrome (WABS), caused by bi‐allelic variants in the DDX11 gene, is a rare cohesinopathy characterized by pre‐ and postnatal growth retardation, microcephaly, intellectual disability, facial dysmorphia, and sensorineural hearing loss due to cochlear hypoplasia. The DDX11 gene codes for an iron–sulfur DNA helicase in the Superfamily 2 helicases and plays an important role in genomic stability and maintenance. Fourteen individuals with WABS have been previously reported in the medical literature. Affected individuals have been of various ethnic backgrounds with different pathogenic variants. We report two unrelated individuals of Ashkenazi Jewish descent affected with WABS, who are homozygous for the c.1763‐1G>C variant in the DDX11 gene. Their phenotype is consistent with previously reported individuals. RNA studies showed that this variant causes an alternative splice acceptor site leading to a frameshift in the open reading frame. Carrier screening of the c.1763‐1G>C variant in the Jewish population revealed a high carrier frequency of 1 in 68 in the Ashkenazi Jewish population. Due to the high carrier frequency and the low number of affected individuals, we hypothesize a high rate of miscarriage of homozygous fetuses and/or subfertility for carrier couples. If the carrier frequency is reproducible in additional Ashkenazi Jewish populations, we suggest including DDX11 to Ashkenazi Jewish carrier screening panels. 相似文献
53.
Relationship of epileptic seizures to sleep stage and sleep depth 总被引:10,自引:0,他引:10
STUDY OBJECTIVES: Interictal epileptiform discharges (IEDs) are facilitated by NREM stages 3 and 4 sleep and as sleep is deepening. To determine whether sleep influences seizures in a similar way to IEDs, we examined seizure rates in various stages of sleep in epilepsy patients undergoing overnight video-EEG-polysomnography (VPSG). DESIGN: Cross-sectional study. SETTING: Neurology Department. PATIENTS, MEASUREMENTS, AND INTERVENTIONS: We reviewed VPSGs from our Sleep and Epilepsy Laboratories to identify patients with recorded seizures during sleep. A total of 55 patients having 117 seizures were identified. RESULTS: Ninety-five percent of seizures occurred in NREM sleep (61% in stage 2, 20% in stage 1, 14% in stages 3 and 4 combined), and 5% in REM sleep. Adjusting for time spent in each stage of sleep, patients had 0.34 seizures per hour in stage 1, 0.38 seizures per hour in stage 2, 0.29 seizures/hr in stage 3 and 4 combined, and 0.09 seizures per hour in REM sleep. Seizures/hour was higher in NREM sleep (0.35 for NREM and 0.09 for REM; p=0.0001). For single seizures occurring in 1 night, seizure rate was significantly higher in NREM stages 1 and 2 as compared to NREM stages 3 and 4 sleep. A significant increase in log delta power, an automated measure of sleep depth, was observed in the 10 minutes prior to seizures. CONCLUSIONS: Both seizures and IEDs are facilitated by NREM sleep. While deeper stages of NREM sleep activate IEDs, lighter stages of NREM sleep promote seizures, at least for single seizures occurring in 1 night. 相似文献
54.
Grunebaum MF Oquendo MA Burke AK Ellis SP Echavarria G Brodsky BS Malone KM Mann JJ 《Journal of affective disorders》2003,75(3):291-296
BACKGROUND: Short-term discontinuation of psychiatric medications is required in many types of research studies. Yet there are few studies of the clinical impact of psychotropic discontinuation. We studied the impact of a short-term medication washout in unipolar depressed patients consecutively admitted to hospital for neuroimaging and cerebrospinal fluid (CSF) studies. METHOD: Patients (n=51) with unipolar depression who were taking antidepressant or mood stabilizing medication at or within 1 week of admission, and who had not been responding satisfactorily, were assessed for severity of psychopathology within 1 week of hospital admission and 41 of the group were reassessed following an approximately 2-week medication washout. RESULTS: On average, patients remained stable during the washout or improved on clinical measures. No serious adverse clinical changes were observed. LIMITATIONS: Potential sample bias, small sample size. CONCLUSION: The results suggest that similar studies can be conducted without causing undue worsening of symptoms. The benefit of medication washout may be related to the fact that many of the patients had been responding poorly to the medication they were taking. There is a need for further research on the effects of medication washout, for example in outpatients or those who are responding well to treatment, but have intolerable side-effects. 相似文献
55.
Kadereit S Junge GR Kleen T Kozik MM Kaminski BA Daum-Woods K Fu P Tary-Lehmann M Laughlin MJ 《Journal of clinical immunology》2003,23(6):485-497
Regulation of nuclear factor of activated T cells-c2 (NFATc2) gene expression is not clearly defined. We previously reported reduced NFATc2 protein expression in cord blood T lymphocytes. Here we show that NFATc2 expression in T cells is dependent in part on the presence of IFN-gamma during primary stimulation, as blocking of IFN-gamma blunted NFATc2 protein and mRNA upregulation. Conversely, addition of exogenous IFN-gamma during stimulation resulted in increased expression of NFATc2 in cord blood T lymphocytes. This correlated with rescue of deficient IFN-gamma expression by cord blood T cells. Rescue of IFN-gamma expression in cord blood T cells was dependent on the presence of antigen-presenting cells, as addition of IFN-gamma during stimulation of purified cord blood T cells did not result in an increase of IFN-gamma expression, and depletion of monocytes ablated the rescue of IFN-gamma expression. Our results point to impaired function in the antigen-presenting cell population of cord blood, playing a role in the hyporesponsiveness of T cells. 相似文献
56.
A reexamination of the role of the RAD52 gene in spontaneous mitotic recombination 总被引:12,自引:0,他引:12
Robert E. Malone Beth A. Montelone Charles Edwards Kevin Carney Merl F. Hoekstra 《Current genetics》1988,14(3):211-223
Summary The RAD52 gene is required for much of the recombination that occurs in Saccharomyces cerevisiae. One of the two commonly utilized mutant alleles, rad52-2, increases rather than reduces mitotic recombination, yet in other respects appears to be a typical rad52 mutant allele. This raises the question as to whether RAD52 is really necessary for mitotic recombination. Analysis of a deletion/insertion allele created in vitro indicates that the null mutant phenotype is indeed a deficiency in mitotic recombination, especially in gene conversion. The data also indicate that RAD52 is required for crossing-over between at least some chromosomes. Finally, examination of the behavior of a replicating plasmid in rad52-1 strains indicates that the frequency of plasmid integration is substantially reduced from that in wild type, a conclusion consistent with a role for RAD52 in reciprocal crossing-over. Analysis of recombinants arising in rad52-2 strains suggests that this allele may result in the increased activity of a RAD52-independent recombinational pathway. 相似文献
57.
Beth B Matsushita F Mounier S Shiggins R Papon B Kernbaum S 《Bulletin de la Societe de pathologie exotique (1990)》1998,91(5 PT 1-2):464-466
More and more foreign tourists are being treated at the American Hospital of Paris. The main reasons for this are the presence of a 24 hour medical and dental emergency service, in addition to the availability of MRI, CT scan and comprehensive laboratory facilities. The hospital is multidisciplinary, where short stay hospitalizations are the rule. English is the second most commonly used language. There is a permanent Japanese language service for Japanese patients. Qualitative data is presented concerning the management of patients according to specialty and nationality. American and Japanese patients admitted to the hospital in 1997 are surveyed according to their mean age, reasons for admission and appropriate specialty as well as mean length of stay noted. The greatest number of hospitalizations in decreasing order and according to nationality are as follows: American, Japanese, Moroccan Egyptian and Saudi Arabian. The consultations and hospitalizations of Japanese patients between 1990 and 1997 are compared. 相似文献
58.
Beth Gordesky-Gold John M. Warrick David P. Kutzler Karama C. Neal Christina M. Coughlin Laurie Tompkins 《Behavior genetics》1996,26(1):49-54
Larvae from seven laboratory strains and eight isofemale lines ofDrosophila melanogaster differ significantly with regard to their responses to light in a photokinesis assay in which the larvae are tested en masse.
Larvae from the CA-2 laboratorystock fail to disperse on assay plates, although observations of individual CA-2 larvae suggest
that the larvae are repelled by light. Larvae from all of the other laboratory stocks and all of the isofemale lines (except
LI2 and NC5) avoid light in the photokinesis assay. Larvae from some stocks are much more strongly repelled by light than
larvae from other stocks. LI2 larvae are unresponsive to light in most replicates of the photokinesis assay, while NC5 larvae
are consistently unresponsive to light. Observations of F1 heterozygotes suggest that the allele(s) that affects the vision of LI2 and NC5 larvae has net effects on the animals' behavior
that are partially dominant and recessive, respectively. 相似文献
59.
Differences in host susceptibility to disease progression in the human challenge model of Haemophilus ducreyi infection
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Spinola SM Bong CT Faber AL Fortney KR Bennett SL Townsend CA Zwickl BE Billings SD Humphreys TL Bauer ME Katz BP 《Infection and immunity》2003,71(11):6658-6663
With human volunteers inoculated at two sites with Haemophilus ducreyi, outcomes for a subject were not independent. In a reinfection trial, 2 of 11 previous pustule formers and 6 of 10 previous resolvers resolved all sites of infection. There was no correlation between serum bactericidal or phagocytic activity and outcome in the trial. These data indicate that different hosts are differentially susceptible to disease progression versus resolution in the model. 相似文献
60.
Robert J. Clarke Beth W. Datskovsky Antony M. Grigonis E. Hazel Murphy 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,91(2):296-302
Summary In visual cortex of normal adult rabbits, callosal projections are restricted to a 2 mm wide band at the area 17/18 border. In adult rabbits which are monocularly enucleated (ME) on the day of birth, the callosal zone extends 4 mm into the medial region of area 17 in the cortex ipsilateral to the remaining eye. In this study, the function of these anomalous callosal projections in ME rabbits was investigated using electrophysiological techniques. A microelectrode was placed in the visual cortex ipsilateral to the enucleated eye at the 17/18 border, bipolar stimulating electrodes were placed in a homotopic location in the contralateral cortex, and averaged evoked responses (AERs) to stimulation were recorded. The stimulating electrodes were then moved mediolaterally in 1 mm steps, and the AERs were recorded for each location of the stimulating electrodes. In the normal rabbit, a maximal short latency evoked response was recorded when the stimulating electrodes were at a location homotopic to the recording electrode. When the stimulating electrodes were moved a distance of 1 mm or more from this optimal position, this short latency response was either absent or dramatically decreased in amplitude, reflecting the precise topographic pattern of the normal callosal projection. In contrast, in ME rabbits, a consistent response was evoked at the 17/18 border when the stimulating electrodes were moved as much as 3 mm medial to the homotopic position. Since antidromically activated responses and both pre- and post-synaptic orthodromically activated responses contribute to the AER, recordings were also made from single cells in some animals. Orthodromically activated single cell responses were evoked by electrical stimulation in the abnormal medial callosal zone of ME rabbits. The data indicate that abnormal callosal projections in ME rabbits can mediate functional interactions between nonhomotopic areas of the primary visual cortices. 相似文献