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101.
Apoptosis in breast carcinoma 总被引:1,自引:0,他引:1
González-Cámpora R Galera Ruiz MR Vázquez Ramírez F Ríos Martín JJ Fernández Santos JM Ramos Martos MM Gómez Pascual A 《Pathology, research and practice》2000,196(3):167-174
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
102.
Paulo AC Gomes MC Casinhas AC Horta A Domingos T 《IMA journal of mathematics applied in medicine and biology》2000,17(3):201-212
The high vaccination coverage required to eradicate communicable diseases like measles, mumps and rubella, with a single dose of vaccine, has prompted many countries to introduce a second dose. In this paper we investigate the conditions to eradicate childhood diseases with multiple doses of vaccine by obtaining explicit analytical solutions to the classical compartment model that assumes an age-independent force of infection and conceptualizes the host population as divided into maternally protected (P), susceptibles (S), latents (E), infectious (I), and removed (R). The solutions allow a quantitative discussion of the long-term impact of vaccination schedules with an arbitrary number of doses of vaccine. It becomes possible to determine the effect of the number of doses, ages at vaccination, and coverage rates of vaccines against childhood diseases. In an example with a two-dose vaccination schedule against measles, we show that, in spite of a second dose, a high (> 90%) immunization coverage in the first dose is still crucial to achieve eradication. With a high first-dose coverage, however, eradication is relatively insensitive to the age of the second dose and requires only moderate coverage rates in the latter. 相似文献
103.
104.
J Benitez C Martinez Frejo C Toledo J Sanchez Fayos C Ramos 《Cancer Genetics and Cytogenetics》1987,26(2):199-207
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
105.
F J Ramos D M McDonald-McGinn B S Emanuel E H Zackai 《American journal of medical genetics》1992,44(6):790-794
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
106.
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
107.
Mariz Vainzof Mayana Zatz Paulo A. Otto John M. Opitz James F. Reynolds 《American journal of medical genetics. Part A》1985,22(1):81-87
Serum creatine-kinase (CK) isoenzyme MB was measured in 53 patients affected by different types of myopathies (20 with Duchenne muscular dystrophy (DMD), eight with the Becker form (BMD), ten with the limb-girdle form (LGMD), six with the facioscapulohumeral form (FSH), and nine affected by polymyositis and in 21 normal control subjects). The aim of this study was to compare each group with the control individuals and to assess the nosologic value of CK-MB activity among some clinically similar dystrophies, which may have an important application for genetic counseling. A statistically significant increased CK-MB activity was found only in the Duchenne and Becker patients when compared with control persons (p < 0.05). When the different groups of patients were compared among themselves, no significant difference was found between DMD and BMD or LGMD and polymyositis. However, a significant difference was found between BMD and LGMD. Based on these data, it is possible, through discriminant analysis, to estimate the relative biochemical probability of an isolated male patient belonging to either group. 相似文献
108.
Tania A. T. Gomes M?nica A. M. Vieira Cecilia M. Abe Daleth Rodrigues Patricia M. Griffin S?nia R. T. S. Ramos 《Journal of clinical microbiology》1998,36(12):3609-3613
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, 13–15, 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
109.
Role of mast cells in plasma permeation due to immune injury of the skin basement membrane. 下载免费PDF全文
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
110.
Dr. M. V. Labay R. Ramos J. A. Hervas J. Reynes B. Gomez 《Intensive care medicine》1985,11(6):326-327
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