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81.

Background  

Although back pain is the most common reason patients use complementary and alternative medical (CAM) therapies, little is known about the willingness of primary care back pain patients to try these therapies. As part of an effort to refine recruitment strategies for clinical trials, we sought to determine if back pain patients are willing to try acupuncture, chiropractic, massage, meditation, and t'ai chi and to learn about their knowledge of, experience with, and perceptions about each of these therapies.  相似文献   
82.
Decay-accelerating factor (DAF, CD55) is a glycosylphosphatidylinositol-anchored membrane protein that restricts complement activation on autologous cells. It is also a ligand for CD97, an activation-associated lymphocyte antigen with seven transmembrane domains. It is widely expressed on cells of both the hematopoietic and nonhematopoietic lineages. Although deficiency of DAF on human erythrocytes is associated with the hemolytic anemia syndrome paroxysmal nocturnal hemoglobinuria, the in vivo biology of DAF is still poorly understood. We addressed the in vivo function of DAF in a knockout mouse model and describe here that deletion of DAF exacerbates autoimmune disease development in MRL/lpr mice, a model for human systemic lupus erythematosus. Compared to DAF-sufficient littermate controls, DAF-deficient female MRL/lpr mice developed exacerbated lymphadenopathy and splenomegaly, higher serum anti-chromatin autoantibody levels, and aggravated dermatitis. Consistent with the phenotype of aggravated dermatitis in DAF-deficient mice, Northern and Western blots and immunofluorescence studies showed DAF to be expressed abundantly in the mouse skin, suggesting that it may play a particularly important role in this tissue. Histology and immunostaining demonstrated inflammatory infiltrate and focal C3 deposition in early skin lesions, mostly along the dermal-epidermal junction. These results reveal a protective function of DAF in the development of a systemic autoimmune syndrome and suggest that dysfunction or down-regulation of DAF may contribute to autoimmune disease pathogenesis and manifestation.  相似文献   
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84.
The herpesvirus entry mediator A (HVEM/HveA) and nectin-1 (HveC/CD111) are two major receptors for herpes simplex virus (HSV). Although structurally unrelated, both receptors can independently mediate entry of wild-type (wt) HSV-1 and HSV-2 by interacting with the viral envelope glycoprotein D (gD). Laboratory strains with defined mutations in gD (e.g. rid1) do not use HVEM but use nectin-2 (HveB/CD112) for entry. The relative usage of HVEM and nectin-1 during HSV infection in vivo is not known. In the absence of a defined in vivo model, we used in vitro approaches to address this question. First, we screened HSV clinical isolates from various origins for receptor tropism and found that all used both HVEM and nectin-1. Second, we determined the numbers of surface receptors on various susceptible and resistant cell lines as well as on primary fibroblasts derived from an individual with cleft lip/palate ectodermal dysplasia (CLPED1). Although CLPED1 cells can only express a defective form of nectin-1, they allowed entry of wild type and mutant HSV strains by usage of either HVEM or nectin-2. Finally, we compared the ability of HVEM and nectin-1 to mediate entry when expressed at varying cell surface densities. Both receptors showed a direct relationship between the number of receptors and HSV susceptibility. Direct comparison of receptors suggests that nectin-1 is more efficient at promoting entry than HVEM. Overall, our data suggest that both receptors play a role during HSV infection in vivo and that both are highly efficient even at low levels of expression.  相似文献   
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86.
Aging is associated with cardiac hypertrophy and progressive decline in heart function. One of the hallmarks of cellular aging is the dysfunction of mitochondria. These organelles occupy around 1/4 to 1/3 of the cardiomyocyte volume. During cardiac aging, the removal of defective or dysfunctional mitochondria by mitophagy as well as the dynamic equilibrium between mitochondrial fusion and fission is distorted. Here, we hypothesized that these changes affect the number of mitochondria and alter their three-dimensional (3D) characteristics in aged mouse hearts. The polyamine spermidine stimulates both mitophagy and mitochondrial biogenesis, and these are associated with improved cardiac function and prolonged lifespan. Therefore, we speculated that oral spermidine administration normalizes the number of mitochondria and their 3D morphology in aged myocardium. Young (4-months old) and old (24-months old) mice, treated or not treated with spermidine, were used in this study (n = 10 each). The number of mitochondria in the left ventricles was estimated by design-based stereology using the Euler-Poincaré characteristic based on a disector at the transmission electron microscopic level. The 3D morphology of mitochondria was investigated by 3D reconstruction (using manual contour drawing) from electron microscopic z-stacks obtained by focused ion beam scanning electron microscopy. The volume of the left ventricle and cardiomyocytes were significantly increased in aged mice with or without spermidine treatment. Although the number of mitochondria was similar in young and old control mice, it was significantly increased in aged mice treated with spermidine. The interfibrillar mitochondria from old mice exhibited a lower degree of organization and a greater variation in shape and size compared to young animals. The mitochondrial alignment along the myofibrils in the spermidine-treated mice appeared more regular than in control aged mice, however, old mitochondria from animals fed spermidine also showed a greater diversity of shape and size than young mitochondria. In conclusion, mitochondria of the aged mouse left ventricle exhibited changes in number and 3D ultrastructure that is likely the structural correlate of dysfunctional mitochondrial dynamics. Spermidine treatment reduced, at least in part, these morphological changes, indicating a beneficial effect on cardiac mitochondrial alterations associated with aging.  相似文献   
87.
BackgroundThe association between elevated hemoglobin A1c (HbA1c) levels and the risk of postoperative infection after penile prosthesis surgery remains controversial.AimTo examine the association between HbA1c levels and penile implant infections in men undergoing inflatable penile prosthesis (IPP) surgery for erectile dysfunction using a large insurance claims database.MethodsThis was a retrospective review using Optum's de-identified Clinformatics Data Mart Database. Male subjects 18 years and older with available laboratory data undergoing IPP insertion between 2003 and 2018 were included. Administrative diagnosis and procedural codes were used to assess subsequent penile implant revision surgery status for either infectious or noninfectious causes. Associated conditions were controlled for such as smoking status, hyperlipidemia, hypertension, obesity status, and Peyronie's disease.OutcomesThe main outcomes were risk of revision for infection and time to revision.ResultsA total of 2,363 individuals underwent initial IPP insertion and had available HbA1c data with a mean HbA1c of 6.9%. The overall IPP infection revision rate was 3.9% and the highest rate of 12.1% was seen in the highest HbA1c group (>10%). After adjusting for demographic and health factors, a higher HbA1c level was associated with a higher risk of revision for infection, with every 1 point increase in HbA1c conferring an increased risk of infection requiring revision by 29% (95% CI 17–42%). When infections did occur, they happened sooner in men with HbA1c > 10.0% with an average of 1.3 months vs 3.5 months in the HbA1c < 6.0% group.Clinical ImplicationsThese findings provide insight into the potential relationship between HbA1c levels and postoperative risk of infection after penile prosthesis surgery and may aid in clinical decision-making.Strengths and LimitationsStrengths include the large sample size, length of data coverage, and real-world analysis of surgeries done across the United States. Limitations include the reliance on insurance claims data, the retrospective study design, and lack of additional relevant clinical variables that may impact infection rates.ConclusionsWhile the overall risk of penile prosthesis infection remains modest, the current report notes an increased risk of infection for diabetic men with poor glycemic control.Chen T, Li S, Eisenberg ML. The Association Between Hemoglobin A1c Levels and Inflatable Penile Prosthesis Infection: Analysis of US Insurance Claims Data. J Sex Med 2021;18:1104–1109.  相似文献   
88.
A forensic Y-STR database generated in the US was compiled with profiles containing a portion or complete typing of 16 STR markers DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS456, DYS458, DYS635, DYS448, and Y GATA H4. There were 17,447 samples in the version of database in which 77% and 20% were collected in North America and Asia, respectively. The database was separated into six general populations, African American, Asian, Caucasian, Hispanic, Indian, and Native American. Each population was further classified into subgroups according to geographic regions. Some subgroups were tested, found to be homogenous and merged together. Allele and haplotype frequencies, as well as sample sizes were summarized. Of the full haplotypes (i.e., 16 STRs without missing data), 93.7% in total population were distinct, 92.9% were population specific, and 89.3% were only observed once. The majority of shared haplotypes were found among North American populations as a result of admixture lasting the past few hundred years. The power of discrimination (PD), coancestry coefficient (Fst), and coefficient of gene differentiation (Gst) at locus and haplotype levels were also calculated. The most polymorphic marker was DYS385; this marker contains a tandem duplication and actually is composed of two loci. Both Gst and Fst estimates were very small with haplotypes composed of a high number of STRs haplotypes (e.g., 10–16 markers), although Gst is slightly more conservative for these extended haplotypes. With Native American removed from the total population data set, the Gst and Fst estimates reduce further. PD was 0.9998 for the total population dataset for all 16 Y-STR markers. Three measures of Y-STR profile frequency were calculated: (1) unconditional haplotype frequency, (2) population substructure adjusted frequency, and (3) binomial upper bound of the haplotype frequency. The binomial upper bound is the most conservative estimate for most forensic applications. Estimates of the weight of a Y-STR haplotype can be estimated using population specific or total population databases.  相似文献   
89.
90.
The effect of lovastatin therapy on LDL-receptor activity in fresh monocytes and on the structure and composition of lipoproteins was determined in 9 patients with familial hypercholesterolemia (FH) and 8 patients with non-familial hypercholesterolemia (NFH). Lovastatin reduced LDL-cholesterol levels by 34.8 and 47.5%, respectively, in the 2 groups of patients, and plasma apo B levels by 33.3 and 42.5%. LDL receptor activity in fresh monocytes increased by 53% and 86% respectively. HDL-cholesterol and plasma apo A-I levels increased only in the NFH group, by 10.2 and 7.1%. Lipoproteins were separated by centrifugation on a zonal rotor. Except for the intermediate density lipoprotein (IDL) fraction, no changes were observed in the structure and composition of the various lipoproteins. The investigations thus demonstrated that lovastatin therapy is associated with a measurable and significant increase of LDL-receptor activity in circulating monocytes that may contribute to the lipid lowering action of the drug.  相似文献   
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