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81.
The idiopathic inflammatory bowel diseases (IBDs), consisting of Crohn's disease and ulcerative colitis, are complex genetic disorders involving chronic inflammation of the intestines. Multiple genetic loci have been implicated through genome-wide searches, but refinement of localization sufficient to undertake positional cloning efforts has been problematic. This difficulty can be obviated through identification of ancestrally shared regions in genetic isolates, such as the Chaldean population, a Roman Catholic group from Iraq. We analyzed four multiply affected American Chaldean families with inflammatory bowel disease not known to be related. We observed evidence for linkage and linkage disequilibrium in precisely the same region of chromosome band 1p36 reported previously in an outbred population. Maximal evidence for linkage was observed near D1S1597 by multipoint analysis (MLOD = 3.01, P = 6.1 x 10(-5)). A shared haplotype (D1S507 to D1S1628) was observed over 27 cM between two families. There was homozygous sharing of a 5 cM portion of that haplotype in one family and over a <1 cM region in the second family. Homozygous sharing of this haplotype near D1S2697 and D1S3669 was observed in one individual in a third multiply affected family, with heterozygous sharing in a fourth family. Linkage in outbred families as well as in this genetic isolate indicates that a pathophysiologically crucial IBD susceptibility gene is located in 1p36. These findings provide a unique opportunity to refine the localization and identify a major susceptibility gene for a complex genetic disorder.  相似文献   
82.
Apoptosis in breast carcinoma   总被引:1,自引:0,他引:1  
Apoptosis may play a major role in determining tumor growth and aggressiveness. The aim of this study was to examine the relationship between apoptosis, expression of bcl-2 and p53 proteins, proliferation index, and other clinicopathological features of breast carcinoma. Sixty-five formalin-fixed paraffin-embedded tissue sections from invasive ductal breast carcinomas were studied for the presence of apoptosis by the terminaldeoxynucleotidyl-transferase-mediated dUTP-FITC nick end-labeling (TUNEL) method. Immunohistochemical methods were also used to determine the expression of estrogen receptor, Ki67, bcl-2 and p53 proteins. The number of apoptotic cells ranged from 2.0 to 236.0/10HPF (mean 36.26, median 28.0). The observation of 30 apoptotic cells/10HPF was more common in tumors > 3 cm, of histological grade III, with a high mitotic index, Ki67 index > or = 300, and p53 positivity; however, statistical significance was found only for the histological grade. Grade I and III tumors displayed an inverse association between the apoptotic index and bcl-2 and p53 protein expressions; grade I tumors frequently expressed bcl-2 (19/28), lacked p53 (20/28), and presented a low number of apoptotic cells (18/28), whereas grade III tumors tended to express p53 (12/17), lacked bcl-2 (13/17), and displayed a high number of apoptotic cells/10HPF (12/17). Multivariate analysis for survival revealed that estrogen receptors and apoptosis were independent variables. These data suggest that apoptosis, rather than proliferation index or expression of bcl-2 or p53 proteins, is an independent factor for the prognosis of survival.  相似文献   
83.
Serial cytogenetic studies have been performed in four patients with myelodysplastic syndromes. In all four a 5q- alteration was present, but with a different pattern of presentation. One patient presented 5q- as the only alteration since diagnosis; two patients acquired this alteration during the course of the disease; and the fourth showed a 5q- plus other alterations since the first cytogenetic study. Likewise, three of the four patients showed a clone with trisomy 8 and without 5q-. According to these observations and others from the literature with similar cytogenetic behavior, we have analyzed the following points: 5q- as a primary event and as the only alteration, 5q- as a secondary event, 5q- plus other alterations, and presence of cytogenetically different clones. Analysis of these points suggests that the 5q- alteration can represent an early mutation conferring a slow capacity of expansion to the affected clones, with the possibility of cytogenetic evolution during the progression of the disease (about 30% of the patients). Likewise, the association of trisomy 8 clones with 5q- clones can be a nonrandom event.  相似文献   
84.
A patient with the diagnosis of Langer-Giedion syndrome (tricho-rhino-phalangeal syndrome type II) and interstitial 8q deletion was also noted to have persistent cloaca and prune belly sequence. This is the first report of this association. If it postulated that these latter embryonic defects may be due to the chromosome abnormality, supporting the definition of contiguous gene syndrome.  相似文献   
85.
A family with Becker type muscular dystrophy is described, in which two females were severely affected, giving the family tree the appearance of dominant inheritance.  相似文献   
86.
The correlation between various adherence patterns and adherence-related DNA sequences in Escherichia coli isolates from 1- to 4-year-old children with and without diarrhea in São Paulo, Brazil, was evaluated. A total of 1,801 isolates obtained from 200 patients and 200 age-matched controls were studied. The adherence patterns found were classified as diffuse, aggregative, aggregative in a 6-h assay, aggregative predominantly in coverslips, localized, localized-like, and noncharacteristic. In general, the DNA sequences used as probes showed excellent specificities (>93%), but their sensitivities varied. Thus, the results of bioassays and assays with DNA probes normally used to search for adherent E. coli did not correlate well, and the best method for the identification of these organisms in the clinical research setting remains controversial. Isolates presenting diffuse adherence or hybridizing with the related daaC probe, or both, were by far the most frequent in patients (31.5, 26.0, and 23.0%, respectively), followed by isolates presenting aggregative adherence or hybridizing with the related EAEC probe, or both (21.5, 13.0, and 10.5%, respectively). None of the different combinations of adherence patterns and adherence-related DNA sequences found were associated with acute diarrhea.The first step in the establishment of the diarrheal diseases caused by the various categories of diarrheagenic Escherichia coli is adherence to epithelial cells of the intestinal mucosa. In vitro assays with eukaryotic cell lines (HeLa and HEp-2 cells) have identified three distinct adherence patterns among fecal isolates of E. coli: localized, diffuse, and aggregative (37, 38, 41). Localized adherence (LA) is characterized by formation of bacterial microcolonies on a restricted area(s) of the cell surface, while diffuse adherence (DA) is the scattered attachment of bacteria over the whole surface of the cell (41). The pattern of aggregative adherence (AA) consists of bacterial attachment to the cells and the intervening cell growth surface in a stacked brick-like lattice (37).The LA pattern was first detected in strains classified as enteropathogenic E. coli (EPEC) among serogroups associated with outbreaks of infantile diarrhea (41). Although E. coli strains exhibiting DA (DAEC) have been isolated at similar frequencies from feces of infants and young children with acute diarrhea and nondiarrheic controls in some populations (3, 10, 11, 14, 18), they were significantly associated with diarrhea in other settings (1, 17, 24, 29, 33). E. coli strains showing AA, termed enteroaggregative E. coli (EAEC), have been linked to sporadic persistent diarrhea (3, 4, 7, 10, 13, 26, 27, 44) and to outbreaks of diarrhea in both developing and developed countries (8, 12, 28, 43). However, the role of EAEC in acute diarrhea is still controversial: some studies have shown a correlation (7, 23, 25, 27, 34, 37), but others (1, 3, 6, 10, 11, 1315, 17, 18, 24, 26, 29, 33, 44) have not.DNA probes derived from adherence-related sequences have been constructed (2, 5, 16, 31, 36) and used in hybridization assays for the detection of the different established and putative categories of diarrheagenic E. coli in many epidemiological studies.We evaluated the relationship between the LA, DA, and AA patterns and hybridization with adherence-related DNA sequences and tested children 1 to 4 years old with and without acute diarrhea for the presence of adherent E. coli strains.  相似文献   
87.
Y Zhang  B F Ramos    B A Jakschik 《Immunology》1992,77(3):422-427
Immune injury of the basement membrane occurs in various human diseases. In the present study, an antibody specific for the basement membrane of mouse skin was injected i.d. into mast cell-deficient WBB6F1-W/Wv mice and their congenic controls, WBB6F1-(+/+). Vascular permeability changes, oedema and fibrin deposition were assessed. Plasma permeation, evaluated by dye exudation, was time and dose dependent in both groups of animals, but significantly less in WBB6F1-W/Wv than in normal mice. At 30 min, the time of maximum in congenic controls, extravasation of the dye was 60% less in mast cell-deficient than in WBB6F1-(+/+) mice. Pyrilamine decreased exudation by 40% in normal but not in WBB6F1-W/Wv mice, indicating that the mast cell mediator histamine contributes to the increase in vascular permeability. Mast cell deficiency also markedly reduced fibrin deposition as assessed by direct immunostaining. Oedema, measured as skin thickness, was 60% less in WBB6F1-W/Wv mice than in their congenic controls. A 5-lipoxygenase blocker inhibited plasma exudation and oedema in normal but not in WBB6F1-W/Wv mice. This indicates that leukotrienes are involved in these processes and that mast cells are important for their production. Local mast cell reconstitution restored dye extravasation and oedema to normal levels as well as the effect of the 5-lipoxygenase inhibitor. These findings show that mast cells and their mediators participate in these inflammatory processes which were initiated by the deposition of IgG on the skin basement membrane.  相似文献   
88.
Membranous laryngotracheobronchitis is a very serious infection which affects the larynx, trachea and bronchi, requiring aggressive therapeutic measures. It has been recently rediscovered as a cause of disease in children. However, it is a very unusual complication of measles. Two infants with measles and membranous laryngotracheobronchitis are reported.  相似文献   
89.
Prevention Science - “Madres Apoyando&nbsp;el Desarrollo Emocional de Sus Hijos” (“Mothers Supporting the Emotional Development of Their Children”) is a parenting...  相似文献   
90.
Purpose

Smoking during pregnancy may be linked to other problematic prenatal health behaviors in women. We examined interrelationships among prenatal smoking, prenatal health behaviors and mental health. The objective of this study was to examine factors that may contribute to variations in prenatal health practices among women who smoke during pregnancy.

Methods

Birth mothers from an adoption study (N?=?912) were interviewed about prenatal smoking, health behaviors, and mental health symptoms at 5 months postpartum.

Results

One-quarter of participants (N?=?222) reported smoking 6 or more cigarettes daily for at least 1 trimester. For mothers who smoked more than 6 cigarettes daily, higher levels of antisocial behaviors (β?=????.14, p?=?.03) and depressive symptoms (β?=????.17, p?=?.03) were associated with less frequent prenatal folate use; antisocial behaviors and depressive symptoms were not associated for prenatal folate use among women who did not smoke more than 6 cigarettes daily. For mothers who did not smoke more than 6 cigarettes daily, more depressive symptoms were associated with fewer prenatal care visits (β?=?.12, p?=?.01). Antisocial behaviors and anxiety symptoms were not associated with prenatal care visits in either group of mothers.

Conclusions for Practice

Maternal antisocial behaviors and depressive symptoms during pregnancy may be markers for poorer adherence to recommendations for folate supplementation among women who smoke 6 or more cigarettes daily during pregnancy, independent of adequacy of prenatal care.

  相似文献   
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