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33.
Duffy S Jackson TL Lansdown M Philips K Wells M Pollard S Clack G Coibion M Bianco AR;ATAC Trialists' Group 《Human reproduction (Oxford, England)》2005,20(1):294-301
BACKGROUND: The 'Arimidex', Tamoxifen, Alone or in Combination (ATAC) trial is a randomized, double-blind trial comparing anastrozole ('Arimidex'), alone or in combination with tamoxifen, relative to tamoxifen alone as 5 year adjuvant treatment for post-menopausal women with early breast cancer. Since tamoxifen is associated with endometrial pathology, the ATAC endometrial sub-protocol was initiated to establish the background prevalence of intrauterine pathology, and to assess prospectively the incidence and nature of intrauterine changes following endocrine therapy. Another aim was to provide data from which advice could be generated on the best endometrium screening method for patients receiving tamoxifen. METHODS: Patients underwent endometrial assessments at entry to the sub-protocol. The baseline investigations comprised transvaginal ultrasound scanning (TVUS), a hysteroscopy and an endometrial biopsy. RESULTS: A total of 285 gynaecologically asymptomatic women from 31 centres in 10 countries entered the endometrial sub-protocol. The mean uterine volume was 47.7 cm3. The median endometrial thickness overall was 3 mm. Twenty-four histologically confirmed, pathological changes were observed. Twenty-three pathologies were confirmed by TVUS, and 21 were identified by hysteroscopy and confirmed by histopathology. Women with or without intrauterine pathology had median endometrial thickness of 5 and 3 mm respectively. CONCLUSIONS: The presence of pathology was associated with increased endometrial thickness. The relative sensitivity and specificity of hysteroscopy and endometrial thickness for the diagnosis of endometrial pathology was comparable to other studies. If screening of the endometrium prior to treatment is appropriate, this study supports the use of an endometrial thickness of 3 mm, as assessed by TVUS, as a threshold for needing further investigation. This study demonstrates that if the endometrial thickness is >3 mm, hysteroscopy and biopsy is the optimal method of detecting intrauterine pathology in women with breast cancer who are about to commence endocrine treatment. 相似文献
34.
Association of ambient air‐pollution levels with acute asthma exacerbation among children in Singapore 总被引:1,自引:0,他引:1
BACKGROUND: Air-pollution levels have been shown to be associated with increased morbidity of respiratory diseases. METHODS: Data for ambient air-pollutant levels, meteorologic factors, and hospitalization or emergency room (ER) visits for acute asthma in Singapore children over a 5-year period (1990-4) were obtained and analyzed for associations by time-series methods. RESULTS: Throughout this period, the annual mean and 24-h mean levels for sulfur dioxide (SO2), nitrogen dioxide (NO2), and total suspended particles (TSP) and maximum 1-h daily average for ozone were generally within the air-quality guidelines established by the World Health Organization (WHO). However, positive correlation between levels of each of these pollutants and daily ER visits for asthma was observed in children aged 3-12 years, but not among adolescents and young adults (13-21 years old). The association with SO2 and TSP persisted after standardization for meteorologic and temporal variables. An adjusted increase in 2.9 ER visits for every 20 microg/m3 increase in atmospheric SO2 levels, lagged by 1 day, was observed on days when levels were above 68 microg/m3. With TSP, an adjusted increase of 5.80 ER visits for every 20 microg/m3 increase in its daily atmospheric levels, lagged by 1 day, was observed on days with levels above 73 microg/m3. Similar results were also obtained after controlling for autocorrelation by time-series analysis. CONCLUSIONS: These associations were observed even though the overall levels of all pollutants were generally within the air-quality guidelines established by the WHO. These findings suggest that asthmatic children are susceptible to increased levels of air pollutants, particularly SO2 and TSP, although the ambient levels are generally within "acceptable" ranges. 相似文献
35.
Screening of thalassaemia carriers in intermediate school of Latium: results of four years'' work. 总被引:1,自引:2,他引:1
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E Silvestroni I Bianco B Graziani C Carboni M Valente M Lerone S U D''Arca 《Journal of medical genetics》1980,17(3):161-164
From 1975 to 1979 the Rome Microcythaemia Centre carried out four health education campaigns and thalassaemia screenings among students of the intermediate schools throughout Latium, under the auspices and with the financial support of the Health Authorities of the Latium region. This project is aimed at avoiding reproduction by pairs of thalassaemia carriers and the birth of homozygous children. During the four campaigns 138 501 students were examined, that is, 70 to 76% of those enrolled. Of these 3343 were found to be thalassaemic. Thus the overall prevalence of thalassaemia in Latium is 2.41%, with minor fluctuations from one province to another and, above all, a slight, though definite, trend towards higher values in the southern part of Latium bordering on Campania. The screening was welcomed by the population and the thalassaemic families, there were no detectable negative side-effects, and it resulted in an increased awareness of the problem of the thalassaemias. 相似文献
36.
Wu Y Egerton G Pappin DJ Harrison RA Wilkinson MC Underwood A Bianco AE 《Molecular and biochemical parasitology》2004,134(2):213-224
Onchocerca volvulus is a tissue-dwelling, vector-borne nematode parasite of humans and the causative agent of onchocerciasis, or 'River Blindness'. Resistance to infection is associated with immune responses to the infective, third-stage (L3) larvae. The antigens of greatest interest for their vaccine potential are surface and secreted molecules. We have previously identified a family of Secreted Larval Acidic Proteins (SLAPs) from the L3 larvae of O. volvulus by biosynthetic labelling. Here, we provide further characterisation of these molecules following cloning and expression of the corresponding cDNAs. Using protein sequencing, we show that SLAPs are members of the alt gene family, first described in the lymphatic filarial parasite, Brugia malayi. Ov-ALT-1 and Ov-ALT-2 correspond with 20 and 18kDa SLAPs. Both proteins are highly acidic and related by sequence, differing chiefly in an 8-amino acid deletion from Ov-ALT-2. By immunochemistry, we confirm that Ov-ALTs are highly stage-specific, being expressed exclusively in late L2 and L3 larvae during growth in the vector. They are synthesised and stored in the glandular oesophagus. Secretion is triggered by the resumption of development in the definitive host and occurs via the pseudocoelom and cuticle. Serological responses in humans to recombinant Ov-ALT-1 indicate that the level of IgG production may be governed by the force of transmission but does not overtly reflect infection status. Immunisation of mice with recombinant Ov-ALT-1 resulted in a modest level of protection against challenge with O. volvulus L3 larvae (P = 0.036). We conclude that Ov-ALT genes, like those of other filariae, are of interest from the standpoint of parasite transmission and infectivity. They may also offer promise as components of a future sub-unit vaccine should the means to enhance protection be achieved. 相似文献
37.
Protective effect of inhaled furosemide on allergen-induced early and late asthmatic reactions 总被引:17,自引:0,他引:17
S Bianco M G Pieroni R M Refini L Rottoli P Sestini 《The New England journal of medicine》1989,321(16):1069-1073
The movement of ions and water across the membranes of bronchial cells is part of the control of the bronchial obstructive response to physical stimuli. In a double-blind, randomized, crossover study, we compared the effect of an aerosol of the loop diuretic furosemide with that of a placebo on the early (within 60 minutes) and late (4 to 12 hours) asthmatic responses to a specific inhaled allergen. We studied 11 subjects with mild allergic asthma, who had both early and late asthmatic responses to a specific inhaled allergen in a preliminary challenge. After placebo administration, the maximal changes (mean +/- SE) from base line in the forced expiratory volume in one second (FEV1) and specific airway resistance were, respectively, a decrease of 35 +/- 4 percent and an increase of 288 +/- 56 percent between 0 and 60 minutes after inhalation of the allergen (early response) and a decrease of 35 +/- 5 percent and an increase of 301 +/- 40 percent between 4 and 12 hours (late response). After furosemide administration (4 ml; 10 mg per milliliter), the early response to inhaled allergen was markedly attenuated in all the subjects, and the late response in all but one. The maximal changes in the FEV1 and specific airway resistance were, respectively, a decrease of 11 +/- 2 percent and an increase of 61 +/- 2 percent between 0 and 60 minutes and a decrease of 20 +/- 4 percent and an increase of 178 +/- 25 percent between 4 and 12 hours (P less than 0.05 for all comparisons). No significant differences were seen in the bronchoconstrictor response to inhaled methacholine after furosemide or placebo administration. We conclude that a furosemide-sensitive mechanism in the airways is involved in the pathogenesis of the reactions of patients with allergic asthma. Whether inhaled furosemide might be useful in the treatment of allergic asthma is uncertain and will require further study. 相似文献
38.
The possible mechanism of minimization of prosthesis-derived bone growth inhibitors by shielding of the metal and the reduction, if not elimination, of the associated metal dissolution was investigated. Titanium, aluminium and vanadium release rates were determined in vitro for Ti alloy specimens both with and without a calcium phosphate coating. Ti orderly oriented wire mesh (OOWM) porous coatings on Ti-6Al-4V substrates were used as the metal specimens. Half of the specimens were coated with a 75 microns calcium phosphate ceramic (CPC coating). Seven reference (OOWM) and seven coated (OOWM-CPC) specimens were immersed and placed along with seven control solutions for various periods in an incubator maintained at 37 degrees C and 5% CO2 - air atmosphere. Whereas the reference solutions showed a Ti release increasing as a function of time, the solutions that had the CPC-coated specimens contained no measurable amounts of titanium. The Al in solution around the CPC-coated specimens was significantly greater than the concentration around non-coated specimens. The Al, however, did not increase significantly with time, at least up to 4 wk immersion. The ceramic coating had a small beneficial effect on V concentration. In the absence of a significant adverse effect of Ti on local bone tissue formation, we focus on the Al data of our study. The possible adverse effect of this element is well documented. The calcium phosphate coating produced a significant increase of biological fixation, yet at the same time a greater Al release into solution, calling into question the significance of CPC coating in shielding adverse metal passive dissolution to explain enhanced bone growth [corrected]. 相似文献
39.
Dezzutti CS Guenthner PC Daniel S Utz U Cabrera T Marshall JH Bianco C Lal RB Cowan EP 《Clinical and diagnostic laboratory immunology》2003,10(4):715-717
A potential public health concern is the reported detection of the human T-lymphotropic virus (HTLV) tax gene in the lymphocytes of up to 11% of a low-risk group of New York City blood donors (NYBD). This study aimed to independently confirm the prevalence of HTLV tax sequences in 293 NYBD. All NYBD tested negative for antibodies to HTLV types 1 and 2 and HTLV Tax. HTLV tax sequences were not detected in the NYBD lymphocytes. These data demonstrate the lack of HTLV-1 tax in this group of NYBD at low risk for HTLV infection. 相似文献
40.
Bone marrow and peripheral blood natural killer cell activity in lymphomas. Its response to IL-2.
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L H Caldera M Leon-Ponte G Acquatella N E Bianco I Blanca 《Clinical and experimental immunology》1992,88(1):143-148
Natural killer (NK) cytotoxic activity was simultaneously investigated in bone marrow mononuclear cells (BMMC) and peripheral blood lymphocytes (PBL) from nine Hodgkin's disease (HD) and 15 non-Hodgkin lymphoma (NHL) untreated patients. Twenty-five PBL samples and seven bone marrow specimens from healthy individuals were also included as control group (C). NK cell activity was evaluated in basal condition and post-stimulation with human recombinant IL-2 (rIL-2). Data were expressed in K values (number of BMMC or PBL needed to lyse 50% of the target cells). In basal condition, both HD and NHL patients showed a NK cell activity comparable to the C group, both in BMMC (HD, K = 2.48 +/- 1.3; NHL, K = 3.8 +/- 2.0; C, K = 3.2 +/- 0.7) and PBL (HD, K = 2.0 +/- 1.0; NHL, K = 2.3 +/- 1.0; C, K = 2.2 +/- 0.2). Stimulation with rIL-2 induced a significant and comparable enhancement of the NK activity in PBL from HD, NHL and C while the response to rIL-2 of the BMMC in most of the HD and NHL patients was significantly greater than the C group. Responder cells were characterized by negative selection with specific MoAb plus complement as a CD3-, CD16+, CD56+ cytotoxic cell and further confirmed by flow cytometry. We postulate that IL-2 activation of bone marrow NK cell precursors, in addition to enhancing the activity of circulating NK, may be of value for the therapeutic rationale of IL-2 in patients with lymphoma. 相似文献