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1.

Background Context

Low back pain (LBP) is a common complaint in clinical practice of multifactorial origin. Although obesity has been thought to contribute to LBP primarily by altering the distribution of mechanical loads on the spine, the additional contribution of obesity-related conditions such as diabetes mellitus (DM) to LBP has not been thoroughly examined.

Purpose

To determine if there is a relationship between DM and LBP that is independent of body mass index (BMI) in a large cohort of adult survey participants.

Study Design

Retrospective analysis of prospectively collected National Health and Nutrition Examination Survey (NHANES) data to characterize associations between LBP, DM, and BMI in adults subdivided into 6 subpopulations: normal weight (BMI 18.5–25), overweight (BMI 25–30), and obese (BMI >30) diabetics and nondiabetics. Diabetes was defined with glycohemoglobin A1c (HbA1c) 6.5%.

Patient Sample

11,756 participants from NHANES cohort.

Outcome Measures

Percentage of LBP reported.

Methods

LBP reported in the 1999-2004 miscellaneous pain NHANES questionnaire was the dependent variable examined. Covariates included HbA1c, BMI, age, and family income ratio to poverty as continuous variables as well as race, gender, and smoking as binary variables. Individuals were further subdivided by weight class and diabetes status. Regression and graphical analyses were performed on the study population as a whole and also on subpopulations.

Results

Increasing HbA1c did not increase the odds of reporting LBP in the full cohort. However, multivariate logistic regression of the 6 subpopulations revealed that the odds of LBP significantly increased with increasing HbA1c levels in normal weight diabetics. No other subpopulations reported significant relationships between LBP and HbA1c. LBP was also significantly associated with BMI for normal weight diabetics and also for obese subjects regardless of their DM status.

Conclusions

LBP is significantly related to DM status, but this relationship is complex and may interact with BMI. These results support the concept that LBP may be improved in normal weight diabetic subjects with improved glycemic control and weight loss, and that all obese LBP subjects may benefit from improved weight loss alone.  相似文献   
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Percutaneous paraspinal pedicle screw implantation (PPSI) reduces soft tissue trauma, blood loss, and postoperative pain but remains technically challenging and associated with radiation exposure and implant-related artefacts. Here, we determined the feasibility, screw accessibility, and the accuracy of navigated PPSI in the thoraco-lumbar sacral spine using intraoperative computed tomography (iCT) and robotic cone-beam CT (CBCT) imaging. Between 2015 and 2018, 465 percutaneous paraspinal pedicle screws were implanted in 75 patients using iCT- or CBCT-based spinal navigation with 230 screws connected to rod reducers during screw assessment imaging (iCT 198; CBCT 32). Clinical and demographic data, intraoperative screw accessibility, and screw accuracy were analyzed and compared to a case-matched cohort of 75 patients undergoing navigated implantation of 481 pedicle screws through an open midline approach. Both iCT and CBCT permitted reliable assessment of each implanted screw, regardless of artifacts caused by rod reducers. Although overall accuracy for correct placement was comparable between PPSI and open surgery (PPSI 96.6%; Open 94.2%), PPSI compared favorably to open surgery regarding complete placement within the pedicle (PPSI 90.1%; Open 75.1%; p  <  0.0001), regional placement accuracy in the lumbar (PPSI 97.8%; Open 91.5%; p  <  0.001), and lumbar-sacral spine (PPSI 100%; Open 81.2%; p  <  0.05), next to the duration of surgery and length of hospitalization. PPSI with iCT- and CBCT-based spinal navigation improves the accuracy, safety, and workflow of navigated spinal instrumentation. Next, a cost-effectiveness and outcome analysis should determine whether iCT and CBCT imaging are truly economically justified. These slides can be retrieved under Electronic Supplementary Material.  相似文献   
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RNU4ATAC pathogenic variants to date have been associated with microcephalic osteodysplastic primordial dwarfism, type 1 and Roifman syndrome. Both conditions are clinically distinct skeletal dysplasias with microcephalic osteodysplastic primordial dwarfism, type 1 having a more severe phenotype than Roifman syndrome. Some of the overlapping features of the two conditions include developmental delay, microcephaly, and immune deficiency. The features also overlap with Lowry Wood syndrome, another rare but well‐defined skeletal dysplasia for which the genetic etiology has not been identified. Characteristic features include multiple epiphyseal dysplasia and microcephaly. Here, we describe three patients with Lowry Wood syndrome with biallelic RNU4ATAC pathogenic variants. This report expands the phenotypic spectrum for biallelic RNU4ATAC disorder causing variants and is the first to establish the genetic cause for Lowry Wood syndrome.
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Kaufmann  R.  Zech  C. J.  Takes  M.  Brantner  P.  Thieringer  F.  Deutschmann  M.  Hergan  K.  Scharinger  B.  Hecht  S.  Rezar  R.  Wernly  B.  Meissnitzer  M. 《Journal of digital imaging》2022,35(1):9-20

Three-dimensional (3D) printing of vascular structures is of special interest for procedure simulations in Interventional Radiology, but remains due to the complexity of the vascular system and the lack of biological tissue mimicking 3D printing materials a technical challenge. In this study, the technical feasibility, accuracy, and usability of a recently introduced silicone-like resin were evaluated for endovascular procedure simulations and technically compared to a commonly used standard clear resin. Fifty-four vascular models based on twenty-seven consecutive embolization cases were fabricated from preinterventional CT scans and each model was checked for printing success and accuracy by CT-scanning and digital comparison to its original CT data. Median deltas (Δ) of luminal diameters were 0.35 mm for clear and 0.32 mm for flexible resin (216 measurements in total) with no significant differences (p?>?0.05). Printing success was 85.2% for standard clear and 81.5% for the novel flexible resin. In conclusion, vascular 3D printing with silicone-like flexible resin was technically feasible and highly accurate. This is the first and largest consecutive case series of 3D-printed embolizations with a novel biological tissue mimicking material and is a promising next step in patient-specific procedure simulations in Interventional Radiology.

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Enteropathogenic E. coli (EPEC) is a major cause of infantile diarrhea, but the pathophysiology underlying associated diarrhea is poorly understood. We examined the role of the luminal membrane Cl(-)/OH(-) exchange process in EPEC pathogenesis using in vitro and in vivo models. Cl(-)/OH(-) exchange activity was measured as OH(-) gradient-driven (36)Cl(-) uptake. EPEC infection (60 minutes-3 hours) inhibited apical Cl(-)/OH(-) exchange activity in human intestinal Caco-2 and T84 cells. This effect was dependent upon the bacterial type III secretory system (TTSS) and involved secreted effector molecules EspG and EspG2, known to disrupt the host microtubular network. The microtubule-disrupting agent colchicine (100 muM, 3 hours) also inhibited (36)Cl(-) uptake. The plasma membrane expression of major apical anion exchanger DRA (SLC26A3) was considerably reduced in EPEC-infected cells, corresponding with decreased Cl(-)/OH(-) exchange activity. Confocal microscopic studies showed that EPEC infection caused a marked redistribution of DRA from the apical membrane to intracellular compartments. Interestingly, infection of cells with an EPEC mutant deficient in espG significantly attenuated the decrease in surface expression of DRA protein as compared with treatment with wild-type EPEC. EPEC infection in vivo (1 day) also caused marked redistribution of surface DRA protein in the mouse colon. Our data demonstrate that EspG and EspG2 play an important role in contributing to EPEC infection-associated inhibition of luminal membrane chloride transport via modulation of surface DRA expression.  相似文献   
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