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101.
Anophthalmia or microphthalmia occur in approximately one in 10 children who have severe visual impairment. These eye malformations are often of unknown aetiology, but can be inherited in autosomal dominant, recessive or X-linked forms, and can also occur in association with specific chromosome abnormalities. Four children are described in the medical literature with microphthalmia or anophthalmia in association with chromosome rearrangements involving distal 3q, suggesting the presence of a micro/anophthalmia gene in this region. We have identified two further patients with micro/anophthalmia and chromosome rearrangements involving 3q26-->3q27 and identified a 6.7 MB common deleted region. Patient 1 had multiple abnormalities including bilateral anophthalmia, abnormalities of the first and second cranial nerves and partial absence of the corpus callosum. His karyotype was 46,XY,del(3)(q26.33q28). Patient 2 had right anophthalmia and left extreme microphthalmia. Her karyotype was 46,XX,del(3)(q26.33q28)t(3;7)(q28;q21.1). Both patients had intrauterine growth retardation (IUGR) and strikingly similar dysmorphic facies consisting of bossed forehead, downward-slanting palpebral fissures, grooved bridge of the nose, prominent low-set ears, small down-turned mouth and small mandible. We identified BAC clones mapping to distal 3q from the ENSEMBL and NCBI Entrez databases. These BAC clones were used as fluorescence in situ hybridisation (FISH) probes to identify the minimum deleted region common to both patients. This interval, between clones RPC11-134F2 and RPC11-132N15, was estimated to be 6.7 MB. We conclude that there is an anophthalmia locus within this interval. Candidate genes mapping to this region include Chordin and DVL3, a homologue of the Drosophila Dishevelled gene.  相似文献   
102.
103.
Summary Strains of the virus of foot-and-mouth disease obtained from different hosts and tissue cultures were tested in tissue cultures of pig, calf, ox and lamb kidneys for their ability to multiply and produce cytopathogenic effects. It was found that whereas cattle and kidney strains of the virus multiplied well in the cultures with cytopathogenic effect, mouse and egg adapted strains did not multiply or show cytopathogenic effect to the same extent especially in the ox and calf kidneys, and this could be correlated with their behaviour in cattle, pigs and cattle tongue epithelium tissue cultures. With all the strains used it was found possible to produce plaques on pig kidney monolayers, but the size and shape of the plaque varied as well as the relation of plaque titre to the titre in mice. The plaque size and plaque population from different sources were compared, and it was found that the relative number of the different plaque sizes varied with the source of the virus and changed in passage in the different systems. The possible significance of these findings in relation to vaccine preparation and adaptation of the virus is discussed.Part of the work described represents the kidney tissue culture side of experiments on attenuated strains of the virus of foot-and-mouth disease. We are grateful to our colleagues at Pirbright for the supply of virus strains and the results of many cattle, egg and mouse titrations.We would also like to thank MissP. Tremayne-Smitli, Mr.W. Chapman and Mr.D. Maskell for their excellent assistance in this work.  相似文献   
104.
Genetic linkage studies have provided significant evidence thata major gene defect, AD3, for familial early-onset Alzheimer'sdisease (EOAD) is located at chromosome 14q24.3, between theshort tandem repeat (STR) markers D14S52 and D14S53 defininga genetic size of 22.7 cM for the AD3 candidate region. We constructeda physical map of the AD3 region using yeast artificial chromosomes(YACs) selected from both the CEPH and megaCEPH YAC librariesusing the AD3 linked STR markers as well as new sequence-taggedsites (STSs) designed based on YAC terminal sequences. The YACmap is contiguous in the region between D14S258 and D14S53,a region of 8.2 cM, and has an estimated physical size of 4–8Mb. The YAC contig map was used as a framework to localize threeknown genes, a pseudogene and two brain expressed sequence tags(ESTs). Linkage analysis studies in two Belgian chromosome 14EOAD families AD/A and AD/B, identified obligate recombinantsin family AD/A with D14S289 and D14S61 reducing the geneticsize of the candidate AD3 region substantially. The minimalAD3 candidate region measured 6.4 cM on the genetic map andis contained within six overlapping megaCEPH YACs that covereda physical distance estimated between 2 and 6 Mb. These YACsas well as other YACs in the YAC contig map are valuable resourcesin gene cloning efforts or genomic sequencing experiments aimingat isolating the AD3 gene.  相似文献   
105.
Passenger leukocytes have been demonstrated to play significant roles in initiating and also regulating immune reactions after organ transplantation. Reliable techniques to detect donor leukocytes in recipients after organ transplantation are essential to analyze the role, function, and behavior of these leukocytes. In this report we describe a simple, reliable method to detect donor cells with low frequencies using peripheral blood samples. Detection of small numbers of major histocompatibility complex (MHC) mismatched cells was first studied using four-color flow cytometry in artificially created cell mixtures. By selecting the CD45(+) population and simultaneous staining with several leukocyte lineage markers (CD3, CD4, CD8, CD56, and CD19), MHC-mismatched leukocytes were consistently detected in cell suspensions prepared from directly stained whole blood samples with a threshold sensitivity as low as 0.1%-0.2%. When the fresh peripheral blood mononuclear cells were separated by conventional Ficoll gradient purification, similar, but slightly lower levels of donor cells were detected. Blood samples obtained 1-5 months after liver, kidney, and intestine transplants revealed that the kind of organ allograft influenced levels and lineage pattern of the circulating donor cells. This procedure provided a simple and reliable method in determining early chimerism in transplant recipients. However, the detection of MHC-mismatched leukocytes of all lineages was much lower when frozen peripheral blood mononuclear cells were used.  相似文献   
106.
This prospective multisite Phase III clinical trial (Miami, New York, New Jersey) investigated the long-term (one year) effects of a 10-week group cognitive-behavioral stress management/expressive supportive therapy (CBSM+) intervention on disadvantaged minority women living with AIDS. The CBSM+ intervention consisted of 10-weekly group session of stress management, cognitive-behavioral skill training, relaxation techniques and expressive-supportive therapeutic strategies. The primary study outcome was self-reported depression scores as measured by the BDI. The CBSM+ Group intervention significantly decreased depression scores on the BDI for women following the intervention and maintained the decreased level at one-year follow-up.  相似文献   
107.
Motility of unicellular organisms occurred early in evolution with the emergence of cilia and flagella. In vertebrates, motile cilia are required for numerous functions such as clearance of the airways and determination of left-right body asymmetry. Ependymal cells lining the brain ventricles also carry motile cilia, but their biological function has remained obscure. Here, we show that ependymal cilia generate a laminar flow of cerebrospinal fluid through the cerebral aqueduct, which we term as 'ependymal flow'. The axonemal dynein heavy chain gene Mdnah5 is specifically expressed in ependymal cells, and is essential for ultrastructural and functional integrity of ependymal cilia. In Mdnah5-mutant mice, lack of ependymal flow causes closure of the aqueduct and subsequent formation of triventricular hydrocephalus during early postnatal brain development. The higher incidence of aqueduct stenosis and hydrocephalus formation in patients with ciliary defects proves the relevance of this novel mechanism in humans.  相似文献   
108.
109.
Recently, the Centers for Disease Control and Prevention reported an accurate, sensitive, specific, reproducible, and quantitative enzyme-linked immunosorbent assay (ELISA) for immunoglobulin G (IgG) antibodies to Bacillus anthracis protective antigen (PA) in human serum (C. P. Quinn, V. A. Semenova, C. M. Elie et al., Emerg. Infect. Dis. 8:1103-1110, 2002). The ELISA had a minimum detectable concentration (MDC) of 0.06 μg/ml, which, when dilution adjusted, yielded a whole-serum MDC of 3.0 μg of anti-PA IgG per ml. The reliable detection limit (RDL) was 0.09 μg/ml, while the dynamic range was 0.06 to 1.7 μg/ml. The diagnostic sensitivity of the assay was 97.6% and the diagnostic specificity was 94.2% for clinically verified cases of anthrax. A competitive inhibition anti-PA IgG ELISA was also developed to enhance the diagnostic specificity to 100%. We report a newly developed fluorescence covalent microbead immunosorbent assay (FCMIA) for B. anthracis PA which was Luminex xMap technology. The FCMIA MDC was 0.006 μg of anti-PA IgG per ml, the RDL was 0.016 μg/ml, and the whole-serum equivalent MDC was 1.5 μg/ml. The dynamic range was 0.006 to 6.8 μg/ml. Using this system, we analyzed 20 serum samples for anti-PA IgG and compared our results to those measured by ELISA in a double-masked analysis. The two methods had a high positive correlation (r2 = 0.852; P < 0.001). The FCMIA appears to have benefits over the ELISA for the measurement of anti-PA IgG, including greater sensitivity and speed, enhanced dynamic range and reagent stability, the use of smaller sample volumes, and the ability to be multiplexed (measurement of more than one analyte simultaneously), as evidenced by the multiplexed measurement in the present report of anti-PA and anti-lethal factor IgG in serum from a confirmed clinical anthrax infection.  相似文献   
110.
Several lines of evidence implicate synaptosomal‐associated protein of 25 kDa (SNAP‐25) in the etiology of attention deficit hyperactivity disorder (ADHD). Most notably, the coloboma mouse mutant, considered to be a good animal model of hyperactivity, has a deletion spanning this gene. Introducing a SNAP‐25 transgene into these animals alleviates hyperlocomotion. We have identified a novel microsatellite repeat in SNAP‐25 located between the 5′UTR and the first coding exon, and tested for association with ADHD. Case‐control analyses suggest there may be a role of this polymorphism in ADHD, with one allele over‐represented in controls and another over‐represented in probands. Within‐family tests of linkage and association confirmed these findings. Further work is needed to ascertain the role of SNAP‐25 in ADHD and assess the functional significance of this polymorphism. © 2002 Wiley‐Liss, Inc.  相似文献   
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