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1.
Danielle E Whittier Elizabeth J Samelson Marian T Hannan Lauren A Burt David A Hanley Emmanuel Biver Pawel Szulc Elisabeth Sornay-Rendu Blandine Merle Roland Chapurlat Eric Lespessailles Andy Kin On Wong David Goltzman Sundeep Khosla Serge Ferrari Mary L Bouxsein Douglas P Kiel Steven K Boyd 《Journal of bone and mineral research》2022,37(3):428-439
Prevalence of osteoporosis is more than 50% in older adults, yet current clinical methods for diagnosis that rely on areal bone mineral density (aBMD) fail to detect most individuals who have a fragility fracture. Bone fragility can manifest in different forms, and a “one-size-fits-all” approach to diagnosis and management of osteoporosis may not be suitable. High-resolution peripheral quantitative computed tomography (HR-pQCT) provides additive information by capturing information about volumetric density and microarchitecture, but interpretation is challenging because of the complex interactions between the numerous properties measured. In this study, we propose that there are common combinations of bone properties, referred to as phenotypes, that are predisposed to different levels of fracture risk. Using HR-pQCT data from a multinational cohort (n = 5873, 71% female) between 40 and 96 years of age, we employed fuzzy c-means clustering, an unsupervised machine-learning method, to identify phenotypes of bone microarchitecture. Three clusters were identified, and using partial correlation analysis of HR-pQCT parameters, we characterized the clusters as low density, low volume, and healthy bone phenotypes. Most males were associated with the healthy bone phenotype, whereas females were more often associated with the low volume or low density bone phenotypes. Each phenotype had a significantly different cumulative hazard of major osteoporotic fracture (MOF) and of any incident osteoporotic fracture (p < 0.05). After adjustment for covariates (cohort, sex, and age), the low density followed by the low volume phenotype had the highest association with MOF (hazard ratio = 2.96 and 2.35, respectively), and significant associations were maintained when additionally adjusted for femoral neck aBMD (hazard ratio = 1.69 and 1.90, respectively). Further, within each phenotype, different imaging biomarkers of fracture were identified. These findings suggest that osteoporotic fracture risk is associated with bone phenotypes that capture key features of bone deterioration that are not distinguishable by aBMD. © 2021 American Society for Bone and Mineral Research (ASBMR). 相似文献
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3.
Pica practices of pregnant women 总被引:2,自引:0,他引:2
R D Horner C J Lackey K Kolasa K Warren 《Journal of the American Dietetic Association》1991,91(1):34-38
This report summarizes current knowledge about pica practices during pregnancy through a systematic review of the literature for the period 1950 through 1990. Pica behavior was considered in terms of its prevalence, risk factors, clinical profile, and effect on pregnancy outcome. Data on pica practices by pregnant women are limited and inconclusive but reveal several interesting relationships. The prevalence of pica among pregnant women in high-risk groups declined between the 1950s and the 1970s but now remains steady, affecting about one fifth of high-risk women. Women at high risk of pica are more likely to be black, to live in rural areas, and to have a positive childhood and family history of pica. The clinical picture of the disorder during pregnancy is not well described. The evidence suggests that pica during pregnancy results in anemia, but it is not definitive. Pica also has been associated with maternal and perinatal mortality. We conclude that the behavior is more prevalent than commonly believed, shows no sign of further decline, and may have serious effects, particularly anemia, on mother and infant. Dietetic practitioners who counsel pregnant women should ask questions about pica when they conduct nutrition assessments of their clients. 相似文献
4.
This study, based on a random sample of adults in a rural North Carolina county, demonstrates racial differences in rural adults' attitudes relating to adolescent sexual issues. Blacks were 50% more likely than Whites to indicate that public schools should provide general health care services, including pregnancy testing and treatment of sexually transmitted diseases, to teenagers; however, they were only half as likely as Whites to approve of sexual experimentation by adolescents. The local community's attitudes must be considered in the implementation of rural adolescent health programs, including acquired immunodeficiency syndrome education. 相似文献
5.
H Nedev K Rolka S Minchev G Kupryszewski K Kolasa Z Kleinrok 《Polish journal of pharmacology and pharmacy》1988,40(3):303-311
Four enkephalin analogs containing C-terminal 2-amino-2-phenyl-1,3-indandione residue were prepared: [Met-NHPID5]--enkephalin (E3), [D-Ala2,Met-NHPID5]--enkephalin (E4), [Leu-NHPID5]--enkephalin (E5), [D-Ala2,Leu-NHPID5]--enkephalin (E6). Their analgesic activities were assayed by three in vivo tests: the "hot plate" method, the reaction to electric painful stimulus and the writhing syndrome test. Neurotoxicity effects were determined by the rota-rod test. The most pronounced analgesic effect was induced by compounds with D-Ala in position 2, particularly in the "hot plate" test. 相似文献
6.
Iwona Stelmach Aleksandra Korzeniewska Wlodzimierz Stelmach Pawel Majak Tomasz Grzelewski Joanna Jerzynska 《Annals of allergy, asthma & immunology》2005,95(4):372-380
BACKGROUND: In cystic fibrosis (CF), the inflammatory process contributes to progressive lung tissue damage. Cysteinyl leukotrienes have been found in the sputum of patients with CF at high concentrations sufficient to cause potent biological effects. OBJECTIVE: To evaluate the effect of anti-inflammatory treatment with montelukast sodium in patients with CF. METHODS: Twenty-six patients aged 6 to 18 years were recruited to this 20-week, randomized, double-blind, placebo-controlled, crossover trial. Patients received montelukast or placebo for 8 weeks in addition to their regular CF treatment. Before and after treatment, findings from spirometry, whole-body plethysmography, and the clinical wheezing and cough scales were evaluated. At the same time, serum and sputum samples were obtained for the measurement of eosinophil cationic protein, interleukin 10 (IL-10), IL-8, and myeloperoxidase levels. RESULTS: Twenty-three patients completed the study. Compared with placebo use, montelukast treatment significantly improved forced expiratory volume in I second, peak expiratory flow, and forced expiratory flow between 25% and 75% and significantly decreased cough and wheezing scale scores (P < .001 for all). There were no significant changes in vital capacity, thoracic gas volume, airway resistance, and residual volume after treatment. Compared with placebo use, montelukast treatment decreased serum and sputum levels of eosinophil cationic protein and IL-8, decreased sputum levels of myeloperoxidase, and increased serum and sputum levels of IL-10 (P < .001 for all). CONCLUSIONS: Montelukast may have measurable anti-inflammatory properties in patients with CF. 相似文献
7.
Interaction of Dr adhesin with collagen type IV is a critical step in Escherichia coli renal persistence 下载免费PDF全文
Selvarangan R Goluszko P Singhal J Carnoy C Moseley S Hudson B Nowicki S Nowicki B 《Infection and immunity》2004,72(8):4827-4835
The pathogenic mechanism of recurrent or chronic urinary tract infection is poorly understood. Escherichia coli cells bearing Dr fimbriae display unique tropism to the basement membrane (BM)-renal interstitium that enables the bacteria to cause chronic pyelonephritis in experimental mice. The renal receptors for Dr-fimbriated E. coli are type IV collagen and decay-accelerating factor (DAF). We hypothesized that type IV collagen receptor-mediated BM-interstitial tropism is essential for E. coli to cause chronic pyelonephritis. To test the role of the type IV collagen tropism of Dr-fimbriated E. coli in renal persistence, we constructed an isogenic mutant in the DraE adhesin subunit that was unable to bind type IV collagen but retained binding to DAF and examined its virulence in the mouse model. The collagen-binding mutant DrI113T was eliminated from the mouse renal tissues in 6 to 8 weeks, while the parent strain caused persistent renal infection that lasted at least 14 weeks (P < or = 0.02). Transcomplementation with the intact Dr operon restored collagen-binding activity, BM-interstitial tropism, and the ability to cause persistent renal infection. We conclude that type IV collagen binding mediated by DraE adhesin is a critical step for the development of persistent renal infection in a murine model of E. coli pyelonephritis. 相似文献
8.
Wojciech Swat Harald Von Boehmer Pawel Kisielow 《European journal of immunology》1994,24(4):1010-1012
To evaluate directly the developmental potential of cortical CD4+8+ thymocytes, highly purified populations of small, nondividing CD4+8+TCRlow and large, dividing CD4+8+TCRhigh thymocytes from H-2d mice expressing a transgenic T cell receptor restricted by H-2Db (major histocompatibility complex class I) molecules were transferred into the thymus of normal, nonirradiated H-2b recipient mice. The results show that both populations generate CD4?8+ thymocytes under these conditions, thus providing conclusive evidence that small cortical thymocytes do not represent a “dead end” but an important intermediate stage in T cell development. 相似文献
9.
Iwona Stelmach Katarzyna Smejda Joanna Jerzynska W?odzimierz Stelmach Pawel Majak Piotr Stelmach Piotr Kuna 《Annals of allergy, asthma & immunology》2007,99(2):170-177
BACKGROUND: Several risk factors for the development of asthma and atopic disease in children have been described. Furthermore, there is consistent evidence that the prevalence of atopy increases with higher socioeconomic status. The knowledge about risk factors and preventive factors for atopy needs to be improved. OBJECTIVE: To compare 2 child populations (foster care and reference children) with different risk and protective factors for the development of atopy. METHODS: The study group consisted of 415 children, living in all 10 community foster homes in Lodz, a large industrial city in Poland. The study was performed from April 2, 2004, to April 30, 2006. The reference group consisted of 500 children, living with their parents at home, recruited from primary care centers. The primary outcome measures were skin prick test results and specific IgE in serum. Secondary outcomes included symptoms of allergic diseases and family history, including life conditions in early childhood. RESULTS: The full analysis set included 408 study children and 402 reference children. Significant differences were observed in the prevalence of atopy between the study and reference groups (11.3% vs 25.9%). We observed more positive skin prick test results in children from the reference group than in study children. To explain this phenomenon, we selected 16 variables that differ in both groups in early life and relate these to atopy. We found that the more cumulative features characteristic of the foster home population (poor living conditions), the lower the risk of atopy. CONCLUSION: Extremely unfavorable environmental circumstances, which are characteristic of the foster home population during early childhood, might prevent from atopy. 相似文献
10.
Klussmann JP Weissenborn SJ Wieland U Dries V Eckel HE Pfister HJ Fuchs PG 《Medical microbiology and immunology》2003,192(3):129-132
Human papillomavirus (HPV) infections are thought to be one of the causal factors in the development of head and neck squamous cell carcinomas (HNSCC), particularly in tumors arising from the Waldeyer's tonsillar ring. We screened 98 carefully stratified HNSCC and different control tissues for the presence of HPV DNA by nested polymerase chain reaction (PCR) specific for genital- and Epidermodysplasia verruciformis (EV)-associated HPVs and by HPV16-specific single step PCR. Typing was performed by direct sequencing and/or sequencing of cloned amplimers. On average HNSCC showed rather low HPV DNA prevalences; 18% of the oral cavity cancers, 8% of nasopharyngeal cancers, 25% of hypopharyngeal cancers and 7% of laryngeal cancers were HPV DNA positive. In contrast, HPV sequences could be detected in 45% of the oropharyngeal cancers, particularly tonsillar carcinomas (58%). Tonsillar carcinomas were significantly more likely to be HPV positive than tumors from any other site ( P<0.001). All tonsillar cancers contained oncogenic HPV types, predominantly HPV16 (13 of 14; 93%). Unaffected tonsils were available from two of these patients, but both tested negative for HPV DNA. Furthermore, no HPV DNA could be found in tonsillar biopsy specimens from control groups. Localization and load of HPV DNA was determined in HPV16-positive tonsillar carcinomas, their metastases and in unaffected mucosa using laser-assisted microdissection and subsequent real time fluorescence PCR. We demonstrated that the HPV genome is located in the cancer cells, whereas the infection of normal mucosa is a rare event. Quantification of HPV16 DNA in samples of seven patients yielded viral loads from 6 to 153 HPV DNA copies per beta-globin gene copy and the load values in both locations were roughly comparable. These loads are comparable with data shown for other HPV-associated lesions. Statistical evaluation of data related to clinicopathological parameters showed a significant correlation of the HPV positivity of tonsillar carcinomas with tumor grading ( P=0.008) and alcohol consumption ( P=0.029). Taken together our findings show a preferential association of HPV DNA with tonsillar carcinomas. Furthermore our results argue for HPV-positive tonsillar carcinomas representing a separate tumor entity, which is less dependent on conventional HNSCC risk factors. 相似文献