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91.
Byung-Ho Yoon Lynne C. Jones Chung-Hwan Chen Edward Y. Cheng Quanjun Cui Wolf Drescher Wakaba Fukushima Valerie Gangji Stuart B. Goodman Yong-Chan Ha Philippe Hernigou Marc Hungerford Richard Iorio Woo-Lam Jo Vikas Khanduja Harry Kim Shin-Yoon Kim Tae-Young Kim Kyung-Hoi Koo 《The Journal of arthroplasty》2019,34(1):169-174.e1
Background
Although alcohol is a leading risk factor for osteonecrosis of the femoral head (ONFH) and its prevalence reportedly ranges from 20% to 45%, there are no unified classification criteria for this subpopulation. In 2015, Association Research Circulation Osseous decided to develop classification criteria for alcohol-associated ONFH.Methods
In June of 2017, Association Research Circulation Osseous formed a task force to conduct a Delphi survey. The task force invited 28 experts in osteonecrosis/bone circulation from 8 countries. Each round of the Delphi survey included questionnaires, analysis of replies, and feedback reports to the panel. After 3 rounds of the survey, consensus was reached on the classification criteria. The response rates for the 3 Delphi rounds were 100% (round 1), 96% (round 2), and 100% (round 3).Results
The consensus on the classification criteria of alcohol-associated ONFH included the following: (1) patients should have a history of alcohol intake >400 mL/wk (320 g/wk, any type of alcoholic beverage) of pure ethanol for more than 6 months; (2) ONFH should be diagnosed within 1 year after alcohol intake of this dose; and (3) patients should not have other risk factor(s).Conclusion
ARCO-established classification criteria to standardize clinical studies concerning AA-ONFH. 相似文献92.
Sanja Stanojevic Felix Ratjen Derek Stephens Annie Lu Yvonne Yau Elizabeth Tullis Valerie Waters 《Journal of cystic fibrosis》2013,12(6):575-583
BackgroundStenotrophomonas maltophilia is one of the most common multi-drug resistant organisms causing pulmonary infections in CF patients. It is unknown whether S. maltophilia infection follows the same pattern and shares similar risk factors for acquisition as described for Pseudomonas aeruginosa.MethodsWe examined all clinical events from 1997 to 2008 in the Toronto CF Database to identify risk factors for the acquisition of S. maltophilia and to define distinct patterns of infection.ResultsWe followed 601 patients over 12 years, during which time one quarter of subjects had at least one positive culture for S. maltophilia; the incidence rate was slightly higher in children (11.6/100 person years) compared with adults (10.6/100 person years). Using multi-variable Cox proportional hazards models, steeper rate of FEV1 decline was a significant risk factor for S. maltophilia acquisition, whereas new infections were less likely to occur with greater oral antibiotic use and a history of Burkholderia cepacia complex infection.ConclusionsThis study illustrates the evolution of S. maltophilia infection over time in a large cohort of adults and children with CF. Younger CF patients, and those with greater lung function decline were at increased risk of S. maltophilia infection. The use of oral antibiotics to maintain lung function may be a way of decreasing the risk of infection. However, the optimal management of CF patients with persistent S. maltophilia infection is not yet known and requires further studies. 相似文献
93.
Insulin-Like Growth Factor I Is a Determinant of Hip Bone Mineral Density in Men Less Than 60 years of Age: MINOS Study 总被引:4,自引:0,他引:4
Several studies show that in elderly men bone mineral density (BMD) is not correlated with the insulin-like growth factor (IGF-I) level, but data are scanty in young men. Results of studies correlating insulin-like growth factor binding protein 3 (IGFBP-3) and BMD in men are discordant. As different hypotheses can explain the discordant results, we evaluated the correlation of BMD with serum IGF-I, IGFBP-3, and IGF-I/IGFBP-3 index in a large cohort of 721 men aged 19–85 years taking into account age, body weight, 17-estradiol, free testosterone, and parathyroid hormone. Serum IGF-I and IGFBP-3 decreased with age (r = –0.44 and r = –0.36, P = 0.0001). After adjustment for confounding variables, IGF-I correlated weakly positively with BMD and with bone mineral apparent density (BMAD) of hip as well as with cortical thickness of femoral neck, both of which are determined mainly by bone resorption, but not with bone size determined by periosteal apposition. IGF-I correlated weakly positively with BMD at the whole body and at the third lumbar vertebra IGFBP-3 and IGF-I/IGFBP-3 index did not correlate with densitometric parameters. In men aged 19–60 years, IGF-I correlated with BMD and BMAD of total hip and with cortical thickness of femoral neck positively and more strongly than in the entire cohort but not with the size of proximal femur. BMD of total hip was 6% higher in men in the highest quartile of IGF-I than in men in the lowest quartile. IGF-I, IGFBP-3, and IGF-I/IGFBP-3 index did not correlate with densitometric parameters of other sites. In the men aged more than 60 years, neither IGF-I nor IGFBP-3 nor IGF-I/IGFBP-3 index correlated with BMD, BMAD, or bone size. In men aged 19–60 years, the most significant hormonal determinants of BMD and BMAD of the hip and of the cortical thickness of femoral neck were 17-estradiol and IGF-I (P < 0.05–0.0001). In men aged more than 60 years, the most significant determinants of hip BMD were 17-estradiol and PTH. In conclusion, IGF-I seems to contribute to the inhibition of bone resorption and to maintaining bone mass of the proximal femur during the phase of slow bone loss in men aged less than 60 years. IGFBP-3 and IGF-I/IGFBP-3 index were not correlated with BMD or bone size.
Supported by a contract with INSERM/Merck Sharp & Dohme Chibret, Paris, France 相似文献
94.
Sukiennik A Carr DB Bonney I Marchand JE Wurm H Sant GR 《Anesthesia and analgesia》2004,98(3):846-50, table of contents
We investigated the effect of epidural local anesthetic blockade on urinary substance P levels in five patients suffering from painful flare-ups of interstitial cystitis. Urine was collected in 24-h intervals commencing at the onset of an epidural bolus of 0.25% bupivacaine followed by maintenance epidural infusions of 0.05% bupivacaine. Substance P was measured by radioimmunoassay. After initiation of the epidural infusion, urinary substance P levels increased and then declined in all patients. All patients reported a decrease in pain intensity. We hypothesize that acute release, followed by depletion, of substance P from bladder sensory nerve endings accounts for the transient increase of peptide levels in urine and may contribute to the decrease in pain intensity during a 3-day epidural infusion. IMPLICATIONS: Substance P levels in urine initially increased and then declined in a series of 5 patients who achieved pain control by epidural local anesthetic infusion during a flare-up of interstitial cystitis. 相似文献
95.
Abdulmassih S. Iskandrian Jeffrey Johnson Tung T. Le Valerie Wasserleben Virginia Cave Jaekyeong Heo 《Journal of nuclear cardiology》1994,1(2):144-149
Background
This study compared the prognostic value of exercise single-photon emission computed tomographic (SPECT) thallium imaging with that of treadmill exercise score in medically treated patients with coronary artery disease (CAD) 相似文献96.
Expression of a cloned denV gene of bacteriophage T4 in Escherichia coli. 总被引:10,自引:2,他引:10 下载免费PDF全文
K Valerie E E Henderson J K de Riel 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(14):4763-4767
A 713-base-pair Hae III fragment from bacteriophage T4 encompassing the denV gene with its preceding promoter has been cloned in a pBR322-derived positive-selection vector and introduced into a variety of DNA repair-deficient uvr and rec and uvr,rec Escherichia coli strains. The denV gene was found to be expressed, probably from its own promoter, causing pyrimidine dimer incision-deficient uvrA, uvrB, uvrC strains to be rescued by the denV gene. A uvrD (DNA helicase II) strain was also complemented, but to a lesser extent. A wild-type strain did not seem to be affected at the UV doses tested. Surprisingly, all recA, recB, and recC strains tested also showed an increased UV resistance, perhaps by reinforcement of the intact uvr system in these strains. Complementation of denV- T4 strains and host-cell reactivation of lambda phage was also observed in denV+ E. coli strains. Equilibrium sedimentation showed that DNA repair synthesis occurred in a UV-irradiated uvrA E. coli strain carrying the cloned denV gene. Southern blotting confirmed our earlier results [Valerie, K., Henderson, E. E. & de Riel, J. K. (1984) Nucleic Acids Res. 12, 8085-8096] that the denV gene is located at 64 kilobases on the T4 map. Phage T2 (denV-) did not hybridize to a denV-specific probe. 相似文献
97.
Genetic complementation of UV-induced DNA repair in Chinese hamster ovary cells by the denV gene of phage T4. 总被引:8,自引:3,他引:8 下载免费PDF全文
K Valerie J K de Riel E E Henderson 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(22):7656-7660
The denV gene of phage T4, encoding the pyrimidine dimer-specific DNA repair enzyme endonuclease V, has been introduced by DNA transfection into the UV-sensitive DNA repair-deficient Chinese hamster ovary (CHO) cell line UV5. Transformants were first selected for resistance to the antibiotic G418 conferred by the neo gene from Tn5 carried by the same plasmid. A majority of the isolated G418-resistant UV5 clones also showed an increased resistance to 254-nm UV light. One clone, designated I-A1, was found to have an intermediate level of colony-forming ability after UV irradiation when compared to UV5 and wild-type AA8 cells. A Southern blot showed that I-A1 carries a single integrated intact copy of the denV gene. Alkaline sucrose gradients revealed a dose-dependent appearance of breaks in the DNA of I-A1 cells following UV-irradiation, while unirradiated cells did not exhibit any significant breaks. Analysis of DNA repair by isopycnic sedimentation showed that DNA excision repair by I-A1 was at least equal to the level of repair in AA8 cells. These results show that the prokaryotic denV gene can restore UV repair capabilities in vivo to CHO UV5 cells defective in repair of UV-induced damage. 相似文献
98.
Age-related changes in cardiac muscarinic receptors: decreased ability of the receptor to form a high affinity agonist binding state 总被引:1,自引:0,他引:1
Cardiac ventricular muscarinic cholinergic receptors and agonist binding properties were determined in Fischer 344 rats at 3, 12, and 24 months of age. Muscarinic receptors were determined by specific (-)-[3H]quinuclidinyl benzilate (QNB) binding, and the agonist binding properties were determined by competition assays. There were no differences in the concentration of the receptor or the dissociation constant of [3H]QNB binding among the three age groups. In cardiac membranes from 3- and 12-month-old animals, 5'-guanylyl-imidodiphosphate (Gpp(NH)p) increased by 16- to 18-fold (p less than .01) the concentration of carbachol required to inhibit [3H]QNB binding by 50% (IC50). At 24 months, however, Gpp(NH)p induced only a 2.7-fold shift in the carbachol IC50 value (p less than .01). The reduced shift was due to an increase in the carbachol IC50 value determined in the absence of Gpp(NH)p (p less than .01). There was no significant differences among the 3-, 12-, and 24-month-old animals in the half-maximal concentration of Gpp(NH)p required to produce the carbachol IC50 shift. The data indicated that with age there is a reduced ability of the muscarinic receptor to form a high affinity agonist binding state. 相似文献
99.
100.
Joerg Heil Valerie Fuchs Michael Golatta Sarah Schott Markus Wallwiener Christoph Domschke Peter Sinn Michael P. Lux Christof Sohn Florian Schütz 《Breast care (Basel, Switzerland)》2012,7(5):364-369
Surgery is still a main therapeutic option in breast cancer treatment. Nowadays, methods of resection and reconstruction vary according to different tumors and patients. This review presents and discusses standards of care and arising questions on how radical primary breast cancer surgery should be according to different clinical situations. In most early breast cancer patients, breast conservation is the method of choice. The discussion on resection margins is still controversial as different studies show conflicting results. Modified radical mastectomy is the standard in locally advanced breast cancer patients, although there are different promising approaches to spare skin or even the nipple-areola complex. A sentinel node biopsy is the standard of care in clinically node-negative invasive breast cancer patients, whereas the significance of axillary lymphonodectomy seems to be questioned through a number of different findings. Although there are interesting findings to modify surgical approaches in very young or elderly breast cancer patients, it will always be an individualized approach if we do not adhere to current guidelines. Up to date, there are no special surgical procedures in BRCA mutation carriers or patients of high-risk families. 相似文献