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71.
Julian Stürznickel Tim Rolvien Alena Delsmann Sebastian Butscheidt Florian Barvencik Stefan Mundlos Thorsten Schinke Uwe Kornak Michael Amling Ralf Oheim 《Journal of bone and mineral research》2021,36(2):271-282
Reduced bone mineral density (BMD; ie, Z-score ≤−2.0) occurring at a young age (ie, premenopausal women and men <50 years) in the absence of secondary osteoporosis is considered early-onset osteoporosis (EOOP). Mutations affecting the WNT signaling pathway are of special interest because of their key role in bone mass regulation. Here, we analyzed the effects of relevant LRP5 and LRP6 variants on the clinical phenotype, bone turnover, BMD, and bone microarchitecture. After exclusion of secondary osteoporosis, EOOP patients (n = 372) were genotyped by gene panel sequencing, and segregation analysis of variants in LRP5/LRP6 was performed. The clinical assessment included the evaluation of bone turnover parameters, BMD by dual-energy X-ray absorptiometry, and microarchitecture via high-resolution peripheral quantitative computed tomography (HR-pQCT). In 50 individuals (31 EOOP index patients, 19 family members), relevant variants affecting LRP5 or LRP6 were detected (42 LRP5 and 8 LRP6 variants), including 10 novel variants. Seventeen variants were classified as disease causing, 14 were variants of unknown significance, and 19 were BMD-associated single-nucleotide polymorphisms (SNPs). One patient harbored compound heterozygous LRP5 mutations causing osteoporosis-pseudoglioma syndrome. Fractures were reported in 37 of 50 individuals, consisting of vertebral (18 of 50) and peripheral (29 of 50) fractures. Low bone formation was revealed in all individuals. A Z-score ≤−2.0 was detected in 31 of 50 individuals, and values at the spine were significantly lower than those at the hip (−2.1 ± 1.3 versus −1.6 ± 0.8; p = .003). HR-pQCT analysis (n = 34) showed impaired microarchitecture in trabecular and cortical compartments. Significant differences regarding the clinical phenotype were detectable between index patients and family members but not between different variant classes. Relevant variants in LRP5 and LRP6 contribute to EOOP in a substantial number of individuals, leading to a high number of fractures, low bone formation, reduced Z-scores, and impaired microarchitecture. This detailed skeletal characterization improves the interpretation of known and novel LRP5 and LRP6 variants. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). 相似文献
72.
Gretl Hendrickx Verena Fischer Astrid Liedert Simon von Kroge Melanie Haffner-Luntzer Laura Brylka Eva Pawlus Michaela Schweizer Timur Yorgan Anke Baranowsky Tim Rolvien Mona Neven Udo Schumacher David J Beech Michael Amling Anita Ignatius Thorsten Schinke 《Journal of bone and mineral research》2021,36(2):369-384
73.
Distal rectus femoris surgery in children with cerebral palsy: results of a Delphi consensus project
Robert M. Kay Kristan Pierz James McCarthy H. Kerr Graham Henry Chambers Jon R. Davids Unni Narayanan Tom F. Novacheck Jason Rhodes Erich Rutz Jeffrey Shilt Benjamin J. Shore Matthew Veerkamp M. Wade Shrader Tim Theologis Anja Van Campenhout Thomas Dreher 《Journal of children's orthopaedics》2021,15(3):270
PurposeThe purpose of this study was for an international panel of experts to establish consensus indications for distal rectus femoris surgery in children with cerebral palsy (CP) using a modified Delphi method.MethodsThe panel used a five-level Likert scale to record agreement or disagreement with 33 statements regarding distal rectus femoris surgery. The panel responded to statements regarding general characteristics, clinical indications, computerized gait data, intraoperative techniques and outcome measures. Consensus was defined as at least 80% of responses being in the highest or lowest two of the five Likert ratings, and general agreement as 60% to 79% falling into the highest or lowest two ratings. There was no agreement if neither threshold was reached.ResultsConsensus or general agreement was reached for 17 of 33 statements (52%). There was general consensus that distal rectus femoris surgery is better for stiff knee gait than is proximal rectus femoris release. There was no consensus about whether the results of distal rectus femoris release were comparable to those following distal rectus femoris transfer. Gross Motor Function Classification System (GMFCS) level was an important factor for the panel, with the best outcomes expected in children functioning at GMFCS levels I and II. The panel also reached consensus that they do distal rectus femoris surgery less frequently than earlier in their careers, in large part reflecting the narrowing of indications for this surgery over the last decade.ConclusionThis study can help paediatric orthopaedic surgeons optimize decision-making for, and outcomes of, distal rectus femoris surgery in children with CP.Level of evidenceV 相似文献
74.
75.
76.
Tim Borges Howard P. Glauert Li -Chuan Chen Ching K. Chow Larry W. Robertson 《Archives of toxicology》1990,64(1):26-30
The possible interrelationships between the effects of dietary selenium and perfluorodecanoic acid (PFDA) on growth and lipid metabolism were studied in the male Sprague Dawley rat. Rats were divided into groups and placed on diets containing three levels of selenium (0.04, 0.2, and 1.0 ppm as sodium selenite). Two weeks later, half the rats in each group received a single 35 mg/kg IP injection of PFDA in corn oil, while their pair-fed companion received only vehicle. Rats injected with PFDA stopped gaining weight, and weighed less than pair-fed controls, despite equal food intakes. Two weeks following PFDA administration the rats were killed and plasma cholesterol and triglycerides, and liver peroxisomal enzyme activities were quantified. In contrast to other peroxisome proliferators, PFDA increased plasma triglycerides while decreasing plasma cholesterol. The rate of peroxisomal fatty acid -oxidation was decreased, even though the activity of fatty acyl-CoA oxidase, the first enzyme in the peroxisomal fatty acid -oxidation pathway, was increased. Dietary selenium, other than increasing the liver to body weight ratio, did not alter growth or lipid metabolism. This study demonstrates, for the first time, the existence of a non-hypotriglyceridemic peroxisome proliferator-PFDA. 相似文献
77.
The most frequent form of idiopathic calcinosis is tumoral calcinosis (TC) which rarely occurs at young ages. We describe
here a TC case of a young boy with its light microscopy completed with electron microscopic examinations. X-ray microanalysis
revealed in the intracellular crystals CaCl2 besides the previously described hydroxyapatite. The significance of this finding is unknown at the moment. 相似文献
78.
The anaesthetic management of the surgical repair of a descending aortic aneurysm in a patient with large, bilateral, pulmonary
bullae is described. Anaesthesia for descending aortic surgery normally involves unilateral, positive-pressure ventilation,
an option which poses some risk of barotrauma in the presence of bilateral bullae. Patients with bullous disease commonly
have severe lung disease and thorough preoperative assessment and preparation are necessary. Intraoperatively, bilateral rupture
of the bullae could be catastrophic and preparations should be made for this possibility. In order to diminish this risk,
a surgical technique including preemptive collapse of the bulla by minithoracotomy and tube drainage, with use of a bronchial
blocker to the affected part of the lung may be used. If rupture occurs, then high frequency jet ventilation may be effective.
Use of a double lumen endobronchial tube may be advantageous for patients with either unilateral and bilateral bullae. Anaesthesia
for patients with bullae should avoid positive-pressure ventilation and nitrous oxide in order to limit the risk of barotrauma
from a ball valve mechanism. In this case, the risk of barotrauma was reduced by performing an inhalational induction of anaesthesia
and limiting peak inflation pressures during thoracotomy. It was elected to use positivepressure ventilation through a double
lumen endobronchial tube following chest incision. A high frequency jet ventilator was available but not employed. Anaesthetic
management was complicated by the presence of pleural adhesions, surgical approach directly through a bulla, and the requirement
for one lung ventilation.
The de i’aone descendante aecouverte cnez un pattent porde grosses bulles bilatérales d’emphysème est discutée, esthésie habituelle
pour une chirurgie de l’aorte descendante site une ventilation mécanique unilatérale et constitue ainsi sque additionnel pour
le porteur de bulles emphysémas bilatérales. Ces patients ont ordinairement des affections onaires graves et l’évaluation
et la préparation préopéraprennent une importance spéciale. Pendant l’intervention, pture de bulles bilatérales peut être
catastrophique et il se préparer à cette éventualité. Pour minimiser ce risque, technique chirurgicale qui inclut le collapsus
préventif de lle par minithoracotomie et drainage, avec installation d’un ieur bronchique sur la partie atteinte du poumon.
Si une re survient, le passage à la ventilation par jet à haute tence peut être salutaire. Le tube endobronchique à double
ère peut présenter des avantages aussi bien dans les cas ulles unilatérales que bilatérales. Chez ces patients, il vaut x
s’abstenir de ventiler avec une pression positive et du xyde d’azote afin de limiter le risque de barotraumisme soupape. Dans
ce cas-ci, on a réussi à limiter le risque arotraumatisme en réalisant une induction par inhalation réduisant la pression
d’inflation de pointe pendant la cotomie. Après l’incision thoracique, on a choisi d’utiliser tilation mécanique avec un tube
endobronchique à double ère. Un ventilateur à jet à haute fréquence était prêt mais as été utilisé. La gestion de l’anesthésie
a été compliquée par dhérences pleurales, par la rencontre d’une bulle d’emphysà l’incision et par l’obligation de ventiler
un seul poumon. 相似文献
79.
80.
I Segal A A Dubb L O Tim A Solomon M C Sottomayor E M Zwane 《British medical journal》1978,1(6111):469-472
The number of Africans in Johannesburg presenting with duodenal ulcers has steadily increased over the past 50 years. The characteristics of 105 patients with duodenal ulcer who presented a Baragwanath Hospital were compared with those of matched and unmatched samples of patients without gastrointestinal conditions in the same hospital. Men with duodenal ulcers were found to be significantly better educated than their controls, most had been born in the town, and more of them were employed at higher, though not the highest, educational levels. These data were used to test Susser's proposition that duodenal ulcers are associated with "early urbanisation." Johannesburg blacks with duodenal ulcer did seem to fit the pattern, but the relation between stress and duodenal ulcer remains unclear. 相似文献