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91.
Tony Wawina-Bokalanga Bert Vanmechelen Valentine Lhermitte Joan Martí-Carreras Valentijn Vergote Fara Raymond Koundouno Joseph Akoi-Bor Ruth Thom Tom Tipton Kimberley Steeds Kita Balla Moussa Ablam Amento Lies Laenen Sophie Duraffour Martin Gabriel Paula Ruibal Yper Hall Mandy Kader-Kond Stephan Günther Guy Baele Cesar Muoz-Fontela Johan Van Weyenbergh Miles W. Carroll Piet Maes 《Emerging infectious diseases》2021,27(1):76
We investigated the genetic profiles of killer cell immunoglobulin-like receptors (KIRs) in Ebola virus–infected patients. We studied the relationship between KIR–human leukocyte antigen (HLA) combinations and the clinical outcomes of patients with Ebola virus disease (EVD). We genotyped KIRs and HLA class I alleles using DNA from uninfected controls, EVD survivors, and persons who died of EVD. The activating 2DS4–003 and inhibitory 2DL5 genes were significantly more common among persons who died of EVD; 2DL2 was more common among survivors. We used logistic regression analysis and Bayesian modeling to identify 2DL2, 2DL5, 2DS4–003, HLA-B-Bw4-Thr, and HLA-B-Bw4-Ile as probably having a significant relationship with disease outcome. Our findings highlight the importance of innate immune response against Ebola virus and show the association between KIRs and the clinical outcome of EVD. 相似文献
92.
93.
Joseph S. Munn Sharon E. Culliton Dianne M. Bryant Steven J. MacDonald Bert M. Chesworth 《The Journal of arthroplasty》2021,36(6):1942-1946
BackgroundApproximately 20% of patients are dissatisfied with their total knee arthroplasty (TKA) at 1-year post-surgery. Met expectations have been found by some to significantly predict satisfaction. The role of met expectations in determining patient satisfaction has not been exhaustively explored. The primary aim of this study is to evaluate if met expectations moderate the relationship between pain and function variables and satisfaction.MethodsPatients who underwent primary TKA for osteoarthritis were included in the study (n = 304). Patient-reported outcomes at pre-surgery and 1-year post-surgery were collected. The Knee Society Score (KSS) satisfaction subscale was used as the dependent variable. Candidate independent variables included the following: demographics, KSS, Knee injury and Osteoarthritis Outcome Score (KOOS), 12-Item Short Form Health Survey (SF-12), Hospital Anxiety and Depression Scale, Pain Catastrophizing Scale, Self-Administered Comorbidity Questionnaire, and University of California Los Angeles activity score. Separate linear regression models were created to test interactions for KSS met expectations with pain and KSS met expectations with function.ResultsSignificant predictors of satisfaction were KSS symptoms (pain), KOOS activities of daily living (function), KSS met expectations, KOOS pre-surgery activities of daily living, body mass index, and SF-12 general health. A significant interaction between met expectations and pain was found (P = .043) and the met expectations and function interaction approached significance (P = .086). For both interactions, as met expectations increased, pain and function predicted satisfaction less strongly.ConclusionMet expectations were found to moderate the relationship between pain and satisfaction. There may be more value in improving pain for patients with low met expectations.Level of evidenceLevel IV. 相似文献
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95.
Bert van Rietbergen Emmanuel Biver Thierry Chevalley Keita Ito Roland Chapurlat Serge Ferrari 《Journal of bone and mineral research》2021,36(7):1351-1363
During aging, changes in endosteal and periosteal boundaries of cortical bone occur that differ between men and women. We here develop a new procedure that uses high-resolution peripheral quantitative CT (HR-pQCT) imaging and 3D registration to identify such changes within the timescale of longitudinal studies. A first goal was to test the sensitivity of the approach. A second goal was to assess differences in periosteal/endosteal expansion over time between men and women. Rigid 3D registration was used to transform baseline and all follow-up (FU) images to a common reference configuration for which the region consisting of complete slices (largest common height) was determined. Periosteal and endosteal contours were transformed to the reference position to determine the net periosteal and endosteal expansion distances. To test the sensitivity, images from a short-term reproducibility study were used (15 female, aged 21 to 47 years, scanned three times). To test differences between men and women, images from a subset of the Geneva Retirees Cohort were used (248 female, 61 male, average age 65 years, 3.5 and 7 years FU). The sensitivity study indicated a least significant change for detecting periosteal/endosteal expansion of 41/31 microns for the radius and 17/26 microns for the tibia. Results of the cohort study showed significant net endosteal retraction only in females at the radius and tibia after 3.5 years (38.0 and 38.4 microns, respectively) that further increased at 7 years FU (70.4 and 70.8 microns, respectively). No significant net periosteal changes were found for males or females at 7 years. The results demonstrate that it is possible to measure changes in endosteal contours in longitudinal studies within several years. For the investigated cohort, significant endosteal retraction was found in females but not in males. Whether these changes in cortical geometry are related to fracture risk remains to be investigated in larger cohorts © 2021 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
96.
Arjan C.Y. Loenen David C. Noriega Carlos Ruiz Wills Jérôme Noailly Pierce D. Nunley Rainer Kirchner Keita Ito Bert van Rietbergen 《The spine journal》2021,21(3):528-537
BACKGROUND CONTEXTManual contouring of spinal rods is often required intraoperatively for proper alignment of the rods within the pedicle screw heads. Residual misalignments are frequently reduced by using dedicated reduction devices. The forces exerted by these devices, however, are uncontrolled and may lead to excessive reaction forces. As a consequence, screw pullout might be provoked and surrounding tissue may experience unfavorable biomechanical loads. The corresponding loads and induced tissue deformations are however not well identified. Additionally, whether the forced reduction alters the biomechanical behavior of the lumbar spine during physiological movements postoperatively, remains unexplored.PURPOSETo predict whether the reduction of misaligned posterior instrumentation might result in clinical complications directly after reduction and during a subsequent physiological flexion movement.STUDY DESIGNFinite element analysis.METHODSA patient-specific, total lumbar (L1–S1) spine finite element model was available from previous research. The model consists of poro-elastic intervertebral discs with Pfirrmann grade-dependent material parameters, with linear elastic bone tissue with stiffness values related to the local bone density, and with the seven major ligaments per spinal motion segment described as nonlinear materials. Titanium instrumentation was implemented in this model to simulate a L4, L5, and S1 posterolateral fusion. Next, coronal and sagittal misalignments of 6 mm each were introduced between the rod and the screw head at L4. These misalignments were computationally reduced and a physiological flexion movement of 15° was prescribed. Non-instrumented and well-aligned instrumented models were used as control groups.RESULTSPulling forces up to 1.0 kN were required to correct the induced misalignments of 6 mm. These forces affected the posture of the total lumbar spine, as motion segments were predicted to rotate up to 3 degrees and rotations propagated proximally to and even affect the L1–2 level. The facet contact pressures in the corrected misaligned models were asymmetrical suggesting non-physiological joint loading in the misaligned models. In addition, the discs and vertebrae experienced abnormally high forces as a result of the correction procedure. These effects were more pronounced after a 15° flexion movement following forced reduction.CONCLUSIONSThe results of this study indicate that the correction of misaligned posterior instrumentation can result in high forces at the screws consistent with those reported to cause screw pullout, and may cause high-tissue strains in adjacent and downstream spinal segments.CLINICAL SIGNIFICANCEProper alignment of spinal posterior instrumentation may reduce clinical complications secondary to unfavorable biomechanics. 相似文献
97.
Chan Curtis Bavinton Benjamin R. Prestage Garrett E. Broady Timothy R. Mao Limin Rule John Wilcock Ben Holt Martin 《Archives of sexual behavior》2022,51(5):2509-2521
Archives of Sexual Behavior - Changes to how gay, bisexual, and other men who have sex with men (GBM) connect with each other and with their communities have implications for HIV prevention. Social... 相似文献
98.
Maria Rosaria Gualano Alessio Corradi Gianluca Voglino Dario Catozzi Elena Olivero Michele Corezzi Fabrizio Bert Roberta Siliquini 《Vaccine》2021,39(6):901-914
Influenza is a disease responsible for thousands of deaths every year. Although healthcare workers (HCWs) represent a way of contagion for patients, vaccination coverage among them is low. Mandatory vaccination has been proposed, but controversies remain. This systematic review and meta-analysis aimed to assess the acceptance of mandatory vaccination by HCWs, and to investigate associated characteristics. MEDLINE, Scopus, Embase, PsycInfo, CINAHL and Web of Science were used to search for studies assessing the topic. PRISMA statements were followed. Of the 13,457 univocal records found, 52 studies were included in the systematic review and 40 in the meta-analysis. The pooled proportion of HCWs accepting the policy was of 61% (95% CI: 53%- 68%) but with great heterogeneity between continents (from 54% in Europe to 69% in Asia) and in different professionals (from 40% in nurses to 80% in students). Vaccinated HCWs agreed more frequently with mandatory vaccination than non-vaccinated ones. More studies that consider mandatory vaccination acceptance as the main outcome are needed, but the results of this study confirm that in some settings the majority of HCWs favour mandatory vaccination. This, combined with effects that a flu epidemic could have if overlapped to pandemics with similar symptoms, requires renewed considerations on mandatory vaccination. 相似文献
99.
Anterograde and retrograde trafficking of brain-derived neurotrophic factor (BDNF) was examined in streptozotocin-diabetic and galactose-fed rats by measuring accumulation of endogenous neurotrophin proximal and distal to two constricting sciatic nerve ligatures and by direct injection of radiolabeled neurotrophin into the sciatic nerve. Compared to controls, accumulation of endogenous BDNF proximal and distal to the ligatures as well as basal levels in non-ligated nerve segments were decreased in streptozotocin-diabetic and galactose-fed rats. Neither streptozotocin diabetes nor galactose intoxication affected the amount of 125I-labeled BDNF retrogradely transported to the DRG after injection into the sciatic nerve. These results suggest that reduced anterograde and retrograde accumulations of BDNF in experimental diabetes are not a result of impaired capacity for receptor-mediated transport. 相似文献
100.
Elizabeth Knyihár-Csillik Ágotha Török Bert Csillik 《The Journal of comparative neurology》1990,297(4):594-612
Substance P-like immunoreactivity (SPLI) was localized in the superficial spinal dorsal horn of the rat by means of light and electron microscopic immunocytochemical techniques. Serial immunocytochemical sections were subjected to densitometric measurements with an electronic Image Analyser, and with aid of a computer program, a two-dimensional reconstruction of the fine neuroanatomical structure of the SPLI-active regions of the lumbosacral upper superficial spinal dorsal horn was obtained. SPLI activity in the superficial dorsal horn outlines four well-marked and distinctly differing regions, called, in the mediolateral sequence, areas A, B, C, and D, plus Cajal's noyeau interstitiel ("lateral spinal nucleus" = "nucleus of the dorsolateral fascicle," L). Lumbosacral dorsal rhizotomy results in an almost complete depletion of SPLI from ipsilateral areas A, B, C, and D; it induces decreased SPLI in the area of the lateral spinal nucleus (L), ipsi- or contralaterally in an alternating fashion. Transection of the segmentally related, ipsilateral peripheral nerve induces a marked depletion of SPLI from areas A, B, and C but only a slight decrease in area D and virtually none in the area of L. Whereas a simple crush of the peripheral nerve (axocompression) induces only a slight depletion of SPLI, if any, semiautomatic densitometric analysis of serial immunocytochemical sections proves that a controlled crush injury (axocontusion) results in depletion of SPLI from the upper dorsal horn, similar to transection of the peripheral nerve. Following regeneration of the ipsilateral, segmentally related peripheral nerve, the original immunocytochemical structure of the superficial dorsal horn is re-established by SPLI-positive axonal sprouts originating from previously damaged dorsal root axons. 相似文献