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N. Zamberlan R. Castello D. Gatti M. Rossini V. Braga E. Fracassi Prof. S. Adami 《Osteoporosis international》1997,7(2):133-137
Treatment with gonadotropin-releasing hormone (GnRH) agonist leads to enhanced bone turnover and accelerated bone loss in premenopausal women with endometriosis, uterine leiomyomatomas and hirsutism. Sodium etidronate is a powerful inhibitor of bone resorption which has been proven efficacious in the prevention and treatment of postmenopausal osteoporosis. The objective of this study was to evaluate the skeletal effects of 6 months of therapy with the depot preparation of the GnRH agonist triptorelin (decapeptil 3.75 mg intramuscularly every 4 weeks) in 24 hirsute patients, aged 24–33 years, with hyperandrogenic chronic anovulation. Ten patients also received cyclical etidronate in an oral dose of 400 mg/day for 2 weeks, followed by an 11-week period of 500 mg/day elemental oral calcium (one cycle). The remaining 14 patients received 500 mg/day of elemental calcium continuously. After 6 months all treatments were discontinued for at least a further 6 months. Bone mineral density (BMD) at lumbar spine and hip (dual-energy X-ray absorptiometry, Sophos LXRA, France) and biochemical markers (serum alkaline phosphatase, osteocalcin, urinary N-telopeptide and hydroxyproline/creatinine ratio) were evaluated at baseline, 6 months and 12 months. In the group given GnRH agonist alone BMD fell significantly at all measured skeletal sites during the first 6 months. In the patients treated with etidronate a significant decrease in BMD was observed at lumbar spine but not in the femoral neck and trochanter, and the changes at lumbar spine and trochanter were significantly smaller than those in the control group. At 6 months bone turnover was also increased in patients treated with GnRH and calcium. Cyclical etidronate prevented the increase in biochemical markers of bone formation and resorption, with the exception of calcium/creatinine excretion, which was significantly increased in both groups. Six months after treatment withdrawal BMD did not recover in either group. Biochemical markers (N-telopeptide, serum alkaline phosphatase) remained increased in those patients previously treated with calcium alone while they remained close to baseline values in the patients treated with cyclical etidronate.Our study indicates that: (1) GnRH agonist therapy causes remarkable bone loss in young individuals with androgen excess who are expected to have increased bone mass; (2) this bone loss can be partially prevented by intermittent cyclical etidronate therapy. 相似文献
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Davide Gatti Francesca Colapietro Elena Fracassi Elisabetta Sartori Franco Antoniazzi Vania Braga Maurizio Rossini Silvano Adami 《Journal of clinical densitometry》2003,6(2):173-177
In patients with osteogenesis imperfecta (OI), a disease characterized by abnormal bone fragility, bone mineral density (BMD) was found to be relatively preserved. Quantitative computed tomography (QCT) is the only available method for directly measuring in vivo both volumetric density and the cross-sectional area. Here we report the data from dual-energy X-ray absorptiometry DXA (spine and hip) and peripheral (pQCT) (ultradistal and proximal radius) measurement of 27 adult patients affected by OI, mostly of type I, compared with a group of healthy persons. In the patients with OI, areal BMD values at both femoral neck and lumbar spine were considerably lower than in control subjects (-32 and -36%, respectively; p<0.001 for body weight and height adjusted values). pQCT volumetric density at the ultradistal radius was 19% lower than in control subjects and this difference rose to 32% for purely cancellous bone tissue. The whole bone cross-sectional area of ultradistal radius, as measured by pQCT, was superimposable to normal. At the proximal radius, both cross-sectional area and cortical area, together with Bending Breaking Resistance Index (BBRI), were significantly lower in OI (-23; -22; -32% respectively; p<0.001 for body weight and height adjusted values), but cortical volumetric density was even slightly higher in the OI group than in control subjects. In conclusion, it appears that the most obvious defect in adults with OI is the inability to acquire an adequate thickness of the cortices of long bone and to achieve or maintain normal trabecular density. 相似文献
15.
Georges Dellatolas Lucia Willadino Braga Ligia do Nascimento Souza Gilberto Nunes Filho Elizabeth Queiroz Gerard Deloche 《Journal of the International Neuropsychological Society》2003,9(5):771-782
The effect of the degree of illiteracy (complete or incomplete) on phonological skills, verbal and visual memory and visuospatial skills is examined in 97 normal Brazilian adults who considered themselves illiterate, and 41 Brazilian school children aged 7 to 8 years, either nonreaders or beginning readers. Similar literacy effects were observed in children and in adults. Tasks involving phonological awareness and visual recognition memory of nonsense figures distinguish the best nonreaders and beginning readers. Children performed better than adults at oral repetition of short items and figure recall, and adults better than children at semantic verbal fluency, digit span, and word list recall. A principal component analysis of the correlations between tasks showed that phonological awareness/reading, phonological memory/oral repetition, and semantic verbal memory/fluency tasks, generated different components. The respective role of culturally based preschool activities and literacy on the cognitive functions that are explored in this study is discussed. 相似文献
16.
Braga M Baccari P Radaelli G DiCarlo V Gianotti L Cristallo M 《Clinical nutrition (Edinburgh, Scotland)》1989,8(4):197-201
To identify patients at high-risk for post-operative infections, several methods have been proposed, including prognostic nutritional index (PNI), instant nutritional assessment (INA) and nutritional assessment (NA). Weight loss (WL) has also been related to post-operative morbidity. We have evaluated the prognostic ability of PNI, INA, NA and WL in a prospective study carried out in 94 patients affected by gastro-intestinal malignancy, who underwent major surgery. Post-operative infections occurred in 26 (27.7%) patients. PNI, INA and NA identified classes of patients with a progressive risk of septic complications. To determine the prognostic ability of PNI, INA, NA and WL, sensitivity, specificity, Youden index and predictive values were evaluated. All methods had a Youden index greater than one, with a positive predictive value ranging from 0.33 to 0.36. Since all the methods studied showed a similar predictive ability, it seems reasonable to identify the high-risk surgical patient by using weight loss in association with those nutritional parameters derived from routine hospital laboratory tests. 相似文献
17.
Seropositivity for and Intestinal Colonization with Entamoeba histolytica and Entamoeba dispar in Individuals in Northeastern Brazil
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Lucia L. Braga Yacy Mendonca Clece A. Paiva Andrea Sales Andre L. M. Cavalcante Barbara J. Mann 《Journal of clinical microbiology》1998,36(10):3044-3045
In a slum community in northeastern Brazil 20% of a sample population was colonized with Entamoeba histolytica or Entamoeba dispar and 10.6% was colonized with E. histolytica alone. No correlation between seropositivity for anti-GalNAc lectin antibody and colonization was found. These results suggest that colonization does not necessarily produce immunity to reinfection. 相似文献
18.
R. Araujo L. Braga Dias F. Huth 《Virchows Archiv : an international journal of pathology》1971,352(4):312-323
Summary The purpose of this study was to determine whether autoimmune nephritis in rats affects subsequent generations. Moreover, it was planned to study the nature of the changes in the kidneys in subsequent generations of rats. In these experiments eight generations of rats were investigated. The first five generations were immunized with a mixture of -Streptococcus hemolyticus with an emulsion of renal cortical substance; the rats were given from 4 to 8 injections. After the fifth generation the animals were not immunized, but their nephritis was considerably more pronounced than in their parents. In the 6th and 8th generations there was a sharp rise in the number of animals that died, mainly pregnant rats and newborns. In the course of the experiments, the animals were found to have hypertension, elevated blood nitrogen and proteinuria. A morphological investigation of the rats of the 6th, 7th, and 8th generations that were not immunized, but were born of immunized parents, revealed membranous-proliferative glomerulonephritis, which according to its clinical course and morphological data resembled the nephrotic syndrome the mixed type of human glomerulonephritis.
Zusammenfassung Die Untersuchungen über den Generationswandel der Autoimmunnephritis der Ratte erstreckten sich über 8 Generationen. Bei den ersten 5 Generationen wurde durch eine 4–8malige Injektion einer Mischung aus beta-hämolytischen Streptokokken mit einer Emulsion aus Nierenrindengewebe eine Immunnephritis erzeugt. Die Ratten der 6. bis 8. Generation erhielten keine immunisierenden Injektionen. Trotzdem kam es in der 6. und 8. Generation zu einem akuten Anstieg der Spontantodesrate besonders unter den graviden und neugeborenen Versuchstieren. Klinisch führte die Immun-Nephritis zu einem Blutdruckanstieg, einer Proteinurie und Erhöhung des Harnstoffes. Histologisch entsprachen die Nierenbefunde der 6.–8. Generation einer membranösen proliferativen Glomerulonephritis.相似文献
19.
Linkage of epidemiological registries can provide cost-effective information on the associations between different diseases or exposures in the population under study and on completeness of surveillance system databases. We describe the program SALI (software for automated linkage in Italy) aimed at matching individual records from medium-sized registries (in the order of 100,000 records), where the desired outcome is to miss as few links as possible and, because of low link-likelihood (< 1%), a manual revision of matched pairs is feasible. SALI, developed in CA-Clipper language, uses registry files in dBase format. It requires only name, surname, and date of birth as key fields, and it allows for spelling errors in Italian or other Latin languages through a specific algorithm. Furthermore, a double-blind procedure ensures data confidentiality. The main linkage procedure is based on four stages, two automatic ones, and two where the operator can decide through specific windows whether to accept stage-selected matches. SALI takes into account possible errors in key fields thus reducing false negatives. It was used to solve the problem of linkage between AIDS and cancer registries in Italy. It can be used with every IBM-compatible computer system, assuring uniquely high portability. 相似文献
20.
P C Braga R Bossi L Allegra 《Methods and findings in experimental and clinical pharmacology》1986,8(5):321-326
"Mucociliary clearance", from a clinical point of view, is one of the most important defense mechanisms of the respiratory mucosa. Clinicians, pneumologists and pharmacologists are greatly interested in methods investigating the cilia, considered the biological engine that continuously moves the physiological and/or pathological bronchial mucous secretions. This paper describes a method for the study of ciliary activity in man. By a simple brushing technique it is possible to obtain samples of ciliated respiratory epithelium, and the ciliary beat can be observed immediately by microscopy (Nomarsky differential interference contrast) in a small thermostatic perfusion chamber. The ciliary image is visualized on a TV monitor by means of a TV camera. Using a new type of digital counter with a phototransistor probe, the beat rate of a single cilium can be measured directly by the monitor screen under physiological or pathological conditions or under drug perfusion. 相似文献