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31.
Dal Zotto L; Quaderi NA; Elliott R; Lingerfelter PA; Carrel L; Valsecchi V; Montini E; Yen CH; Chapman V; Kalcheva I; Arrigo G; Zuffardi O; Thomas S; Willard HF; Ballabio A; Disteche CM; Rugarli EI 《Human molecular genetics》1998,7(3):489-499
We have recently reported isolation of the gene responsible for X- linked
Opitz G/BBB syndrome, a defect of midline development. MID1 is located on
the distal short arm of the human X chromosome (Xp22. 3) and encodes a
novel member of the B box family of zinc finger proteins. We have now
cloned the murine homolog of MID1 and performed preliminary expression
studies during development. Mid1 expression in undifferentiated cells in
the central nervous, gastrointestinal and urogenital systems suggests that
abnormal cell proliferation may underlie the defect in midline development
characteristic of Opitz syndrome. We have also found that Mid1 is located
within the mouse pseudoautosomal region (PAR) in Mus musculus , while it
seems to be X- specific in Mus spretus. Therefore, Mid1 is likely to be a
recent acquisition of the M. musculus PAR. Genetic and FISH analyses also
demonstrated a high frequency of unequal crossovers in the murine PAR,
creating spontaneous deletion/duplication events involving Mid1. These data
provide evidence for the first time that genetic instability of the PAR may
affect functionally important genes. In addition, we show that MID1 is the
first example of a gene subject to X-inactivation in man while escaping it
in mouse. These data contribute to a better understanding of the molecular
content and evolution of the rodent PAR.
相似文献
32.
33.
DL?MagerEmail author AD?Haffajee PM?Devlin CM?Norris MR?Posner JM?Goodson 《Journal of translational medicine》2005,3(1):27
Background
The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls. 相似文献34.
Nucleotide sequence of htpB, the Legionella pneumophila gene encoding the 58-kilodalton (kDa) common antigen, formerly designated the 60-kDa common antigen. 总被引:7,自引:4,他引:7 下载免费PDF全文
J S Sampson S P O''''Connor B P Holloway B B Plikaytis G M Carlone L W Mayer 《Infection and immunity》1990,58(9):3154-3157
Gene htpB, which encodes the 58-kilodalton protein of Legionella pneumophila, was cloned in Escherichia coli and its complete nucleotide sequence was determined. Analysis of this sequence revealed an open reading frame of 1,644 nucleotides encoding a protein with a predicted molecular mass of 57,952 daltons. Data obtained by amino-terminal sequencing of the purified 58-kilodalton protein agreed, except for one amino acid residue, with the predicted amino acid sequence, identifying this open reading frame as htpB. A comparison of the primary structure of this protein to other proteins of similar molecular weights from E. coli, Mycobacterium leprae, M. tuberculosis, and Coxiella burnetii revealed significant regions of sequence similarity, which are discussed. 相似文献
35.
Fatalities due to anaphylactic reactions to foods 总被引:27,自引:0,他引:27
Bock SA Muñoz-Furlong A Sampson HA 《The Journal of allergy and clinical immunology》2001,107(1):191-193
Fatal anaphylactic reactions to foods are continuing to occur, and better characterization might lead to better prevention. The objective of this report is to document the ongoing deaths and characterize these fatalities. We analyzed 32 fatal cases reported to a national registry, which was established by the American Academy of Allergy, Asthma, and Immunology, with the assistance of the Food Allergy and Anaphylaxis Network, and for which adequate data could be collected. Data were collected from multiple sources including a structured questionnaire, which was used to determine the cause of death and associated factors. The 32 individuals could be divided into 2 groups. Group 1 had sufficient data to identify peanut as the responsible food in 14 (67%) and tree nuts in 7 (33%) of cases. In group 2 subjects, 6 (55%) of the fatalities were probably due to peanut, 3 (27%) to tree nuts, and the other 2 cases were probably due to milk and fish (1 [9%] each). The sexes were equally affected; most victims were adolescents or young adults, and all but 1 subject were known to have food allergy before the fatal event. In those subjects for whom data were available, all but 1 was known to have asthma, and most of these individuals did not have epinephrine available at the time of their fatal reaction. Fatalities due to ingestion of allergenic foods in susceptible individuals remain a major health problem. In this series, peanuts and tree nuts accounted for more than 90% of the fatalities. Improved education of the profession, allergic individuals, and the public will be necessary to stop these tragedies. 相似文献
36.
Estimation of the genetic contribution of presenilin-1 and -2 mutations in a population-based study of presenile Alzheimer disease 总被引:11,自引:4,他引:11
Cruts M; van Duijn CM; Backhovens H; Van den Broeck M; Wehnert A; Serneels S; Sherrington R; Hutton M; Hardy J; St George-Hyslop PH; Hofman A; Van Broeckhoven C 《Human molecular genetics》1998,7(1):43-51
Two closely related genes, the presenilins ( PS ), located at chromosomes
14q24.3 and 1q42.1, have been identified for autosomal dominant Alzheimer
disease (AD) with onset age below 65 years (presenile AD). We performed a
systematic mutation analysis of all coding and 5'-non-coding exons of PS -1
and PS -2 in a population-based epidemiological series of 101 unrelated
familial and sporadic presenile AD cases. The familial cases included 10
patients of autosomal dominant AD families sampled for linkage analysis
studies. In all patients mutations in the amyloid precursor protein gene (
APP ) had previously been excluded. Four different PS -1 missense mutations
were identified in six familial cases, two of which where autosomal
dominant cases. Three mutations resulted in onset ages above 55 years, with
one segregating in an autosomal dominant family with mean onset age 64
years (range 50-78 years). One PS -2 mutation was identified in a sporadic
case with onset age 62 years. Our mutation data provided estimates for PS
-1 and PS -2 mutation frequencies in presenile AD of 6 and 1% respectively.
When family history was accounted for mutation frequencies for PS -1 were
9% in familial cases and 18% in autosomal dominant cases. Further,
polymorphisms were detected in the promoter and the 5'-non-coding region of
PS -1 and in intronic and exonic sequences of PS -2 that will be useful in
genetic association studies.
相似文献
37.
Wen MC Wei CH Hu ZQ Srivastava K Ko J Xi ST Mu DZ Du JB Li GH Wallenstein S Sampson H Kattan M Li XM 《The Journal of allergy and clinical immunology》2005,116(3):517-524
BACKGROUND: Chinese herbal medicine has a long history of human use. A novel herbal formula, anti-asthma herbal medicine intervention (ASHMI), has been shown to be an effective therapy in a murine model of allergic asthma. OBJECTIVE: This study was undertaken to compare the efficacy, safety, and immunomodulatory effects of ASHMI treatment in patients with moderate-severe, persistent asthma with prednisone therapy. METHODS: In a double-blind trial, 91 subjects underwent randomization. Forty-five subjects received oral ASHMI capsules and prednisone placebo tablets (ASHMI group) and 46 subjects received oral prednisone tablets and ASHMI placebo capsules (prednisone group) for 4 weeks. Spirometry measurements; symptom scores; side effects; and serum cortisol, cytokine, and IgE levels were evaluated before and after treatment. RESULTS: Posttreatment lung function was significantly improved in both groups as shown by increased FEV(1) and peak expiratory flow findings (P<.001). The improvement was slightly but significantly greater in the prednisone group (P<.05). Clinical symptom scores, use of beta(2)-bronchodilators, and serum IgE levels were reduced significantly, and to a similar degree in both groups (P<.001). T(H)2 cytokine levels were significantly reduced in both treated groups (P<.001) and were lower in the prednisone-treated group (P<.05). Serum IFN-gamma and cortisol levels were significantly decreased in the prednisone group (P<.001) but significantly increased in the ASHMI group (P<.001). No severe side effects were observed in either group. CONCLUSION: Anti-asthma herbal medicine intervention appears to be a safe and effective alternative medicine for treating asthma. In contrast with prednisone, ASHMI had no adverse effect on adrenal function and had a beneficial effect on T(H)1 and T(H)2 balance. 相似文献
38.
L Ozzello CM De Rosa EW Blank K Cantell RL Ceriani DV Habif Sr 《Breast cancer research and treatment》1993,25(3):265-276
Summary An immunoconjugate composed of natural interferon (nIFN) bound in a noncleavable fashion to a monoclonal antibody (MoAb) recognizing a breast epithelial membrane mucin (Mc5) was used to treat xenografts of a human mammary carcinoma cell line (MCF-7) growing in nude mice. The immunoconjugate (nIFN/Mc5) was administered as 20 intralesional (i.l.) injections to 1 of 2 xenografts in each animal. It was found that nIFN/Mc5 produced a significant enhancement of the growth inhibitory actions of nIFN on the injected tumors. Further enhancement was obtained when nIFN or nIFN together with Mc5 (at a dose 10 times larger than that present in nIFN/Mc5) were added to the immunoconjugate. Biodistribution experiments showed that the uptake of125I-nIFN/Mc5 by the tumors was greater and its elimination slower than for125I-nIFN alone or conjugated to irrelevant mouse IgG1. In addition, the immunoconjugate up-regulated the antigenic expression of a breast epithelial membrane mucin by the carcinoma cells, an up-regulation which was not significantly different from that produced by nIFN alone. The contralateral noninjected tumors exposed to systemic levels of the immunoconjugate showed an enhancement of antitumor effects, but to a lesser extent than the injected tumors. These findings suggest that the enhancement of the growth inhibitory action of the immunoconjugate was related to the specific binding of Mc5 which targeted the IFN to the carcinoma cells and impeded its elimination. It is likely that the targeting was favored by the IFN-mediated up-regulation of antigenic expression by the carcinoma cells, thereby producing a cascade of interrelated effects. The results of this study point out the feasibility and potential usefulness of IFN treatment by means of immunoconjugates as well as the worth of pursuing and improving this form of therapy. 相似文献
39.
To find out the efficacy of sucralfate in preventing gastrointestinal side effects of non-steroidal anti-inflammatory drugs (NSAIDs) a prospective, randomised single blind study was conducted from 1989 to 1992. Patients with osteoarthritis, rheumatoid arthritis and other long standing painful conditions, who were expected to receive NSAIDs for over three months, were recruited into the study. All medicines were discontinued for a period of 10–15 days prior to initial endoscopic assessment. NSAID therapy was started and the patients were randomised to receive either placebo (group A) or sucralfate (group B) in addition. Patient were reassessed clinically every week and an endoscopic examination was repeated after 6–8 weeks of follow-up. A total of 176 patients were studied in group A (n=91) and group B (n=85). At the end of 8 weeks gastrointestinal symptoms were present in 30.6% and 26.4% patients of group A and B respectively. Endoscopic assessment showed superficial lesions in 36.5% and 18.7% while endoscopic ulcer in 2.4% and 1.1% patients of groups A and B respectively. Thus in patients receiving chronic NSAID therapy, simultaneous administration of sucralfate reduces the incidence of superficial gastric lesions but has no significant effect on symptoms or ulcer formation.KEY WORDS: Gastropathy, Sucralfate, Nonsteroidal anti-inflammatory drugs 相似文献
40.
Multivariate random length data occur when we observe multiple measurements of a quantitative variable and the variable number of these measurements is also an observed outcome for each experimental unit. For example, for a patient with coronary artery disease, we may observe a number of lesions in that patient's coronary arteries, along with percentage of blockage of each lesion. Barnhart and Sampson first proposed the multiple population model to analyse multivariate random length data without covariates. This paper extends their approach to deal with multiple covariates. We propose a new multiple population regression model with covariates, and discuss the estimation issues. We analyse data from the TYPE II coronary intervention study to illustrate the methodology. 相似文献