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41.
42.
In past decades, much effort has been invested in developing therapies for spinal injuries. Lack of standardization of clinical read-out measures, however, makes direct comparison of experimental therapies difficult. Damage and therapeutic effects in vivo are routinely evaluated using rather subjective behavioral tests. Here we show that manganese-enhanced magnetic resonance imaging (MEMRI) can be used to examine the extent of damage following spinal cord injury (SCI) in mice in vivo. Injection of MnCl2 solution into the cerebrospinal fluid leads to manganese uptake into the spinal cord. Furthermore, after injury MEMRI-derived quantitative measures correlate closely with clinical locomotor scores. Improved locomotion due to treating the detrimental effects of SCI with an established therapy (neutralization of CD95Ligand) is reflected in an increase of manganese uptake into the injured spinal cord. Therefore, we demonstrate that MEMRI is a sensitive and objective tool for in vivo visualization and quantification of damage and functional improvement after SCI. Thus, MEMRI can serve as a reproducible surrogate measure of the clinical status of the spinal cord in mice, potentially becoming a standard approach for evaluating experimental therapies.  相似文献   
43.
BACKGROUND: Whether or not cytokine secretion is impaired in patients withsmall-cell lung cancer (SCLC), is unknown. We therefore investigatedwhether cytokine secretion by immunocompetent cells may be suppressedin patients with SCLC PATIENTS AND METHODS: We determined cytokine secretion by lymphocytes and monocytesin whole blood cell cultures from 58 patients with SCLC, 95patients with non-small-cell lung cancer (NSCLC), 10 patientswith nonmalignant lung disease and from 44 normal healthy individualsby using an enzyme-linked immunosorbent assay (ELISA) specificfor the different cytokines measured. RESULTS: Compared to normal controls, immunocompetent cells from patientswith SCLC secreted significantly lower amounts of IL-2, IFN  相似文献   
44.
BACKGROUNDTo understand the features of a replicating vaccine that might drive potent and durable immune responses to transgene-encoded antigens, we tested a replication-competent adenovirus type 4 encoding influenza virus H5 HA (Ad4-H5-Vtn) administered as an oral capsule or via tonsillar swab or nasal spray.METHODSViral shedding from the nose, mouth, and rectum was measured by PCR and culturing. H5-specific IgG and IgA antibodies were measured by bead array binding assays. Serum antibodies were measured by a pseudovirus entry inhibition, microneutralization, and HA inhibition assays.RESULTSAd4-H5-Vtn DNA was shed from most upper respiratory tract–immunized (URT-immunized) volunteers for 2 to 4 weeks, but cultured from only 60% of participants, with a median duration of 1 day. Ad4-H5-Vtn vaccination induced increases in H5-specific CD4+ and CD8+ T cells in the peripheral blood as well as increases in IgG and IgA in nasal, cervical, and rectal secretions. URT immunizations induced high levels of serum neutralizing antibodies (NAbs) against H5 that remained stable out to week 26. The duration of viral shedding correlated with the magnitude of the NAb response at week 26. Adverse events (AEs) were mild, and peak NAb titers were associated with overall AE frequency and duration. Serum NAb titers could be boosted to very high levels 2 to 5 years after Ad4-H5-Vtn vaccination with recombinant H5 or inactivated split H5N1 vaccine.CONCLUSIONReplicating Ad4 delivered to the URT caused prolonged exposure to antigen, drove durable systemic and mucosal immunity, and proved to be a promising platform for the induction of immunity against viral surface glycoprotein targets.TRIAL REGISTRATIONClinicalTrials.gov NCT01443936 and NCT01806909.FUNDINGIntramural and Extramural Research Programs of the NIAID, NIH (U19 AI109946) and the Centers of Excellence for Influenza Research and Surveillance (CEIRS), NIAID, NIH (contract HHSN272201400008C).  相似文献   
45.
BACKGROUND: The cardiovascular (CV) safety of non-steroidal anti-inflammatory drugs (NSAIDs) and selective cyclooxygenase-2 inhibitors has been the subject of considerable debate. OBJECTIVE: The objective of this study was to determine the risk of CV events with lumiracoxib by meta-analysis of all completed, randomized controlled trials (RCTs) of > or =1 week and up to 1 year in duration of patients with osteoarthritis and rheumatoid arthritis. METHODS: The Novartis Lumiracoxib Clinical Trial Database, which includes all clinical studies conducted to date with lumiracoxib, was reviewed. Data were extracted from RCTs of > or =1 week and up to 1 year in duration, the maximum study duration; 34,668 patients were included in standard and cumulative meta-analyses. Twenty-two RCTs of lumiracoxib 100 to 1200 mg daily were identified; 22,781 patients were included in 1-year trials. Mean age of the patients was 61.5 years and 74% were female. More than 50% of the patients in these studies had hypertension at baseline and 6% had diabetes. Parameters analyzed were the Antiplatelet Trialists' Collaboration (APTC) composite CV end point of myocardial infarction (MI), stroke (ischemic and hemorrhagic), and CV death; MI alone; and stroke alone. Twenty-one of the 22 RCTs have been published. RESULTS: For all 3 parameters, relative risk (RR) was calculated versus non-naproxen NSAIDs, naproxen, and placebo. The results were as follows: for the APTC end point versus non-naproxen NSAIDs: RR 0.83, 95% CI, 0.46-1.51; versus naproxen: RR 1.49, 95% CI, 0.94-2.36; versus placebo: RR 1.08, 95% CI, 0.41-2.86; for MI alone versus non-naproxen NSAIDs: RR 0.80, 95% CI, 0.28-2.25; versus naproxen: RR 1.69, 95% CI, 0.82-3.48; versus placebo: RR 1.27, 95% CI, 0.25-6.56; and for stroke alone versus non-naproxen NSAIDs: RR 0.91, 95% CI, 0.35-2.35; versus naproxen: RR 1.42, 95% CI, 0.70-2.91; versus placebo: RR 0.59, 95% CI, 0.13-2.74. Cumulative meta-analyses of lumiracoxib versus all comparators (placebo, diclofenac, ibuprofen, celecoxib, rofecoxib, and naproxen) did not find any significant differences in APTC, MI alone, or stroke alone. CONCLUSION: This meta-analysis of 34,668 patients receiving > or =1 week and up to 1 year of treatment found no evidence that lumiracoxib was associated with a significant increase in CV risk compared with naproxen, placebo, or all comparators (placebo, diclofenac, ibuprofen, celecoxib, rofecoxib, and naproxen).  相似文献   
46.
The aim was to investigate changes in the tumor bed on magnetic resonance mammography (MRM) after intraoperative radiotherapy (IORT) and whether they would limit the diagnostic value of posttherapeutic MRM. We retrospectively investigated 36 patients undergoing MRM after IORT (median interval 2.8 years, range 0.4-7.1). Wound cavities with fat necrosis were common after IORT (81%). They were associated with persisting contrast enhancement, i.e., enhancement was mostly seen irrespective of the posttherapeutic interval. It normally presented as rim enhancement and did not cause any diagnostic uncertainty if viewed together with other tissue characteristics. We do not expect a limited diagnostic value of MRM after IORT.  相似文献   
47.
Heterozygous mutations in the CD95 (APO-1/Fas) receptor occur in most individuals with autoimmune lymphoproliferative syndrome (ALPS) and dominantly interfere with apoptosis by an unknown mechanism. We show that local or global alterations in the structure of the cytoplasmic death domain from nine independent ALPS CD95 death-domain mutations result in a failure to bind the FADD/MORT1 signaling protein. Despite heterozygosity for the abnormal allele, lymphocytes from ALPS patients showed markedly decreased FADD association and a loss of caspase recruitment and activation after CD95 crosslinking. These data suggest that intracytoplasmic CD95 mutations in ALPS impair apoptosis chiefly by disrupting death-domain interactions with the signaling protein FADD/MORT1.  相似文献   
48.
OBJECTIVE: It is currently unknown whether human cartilage properties change during short periods of partial load bearing. We used a post-ankle fracture model to explore whether changes in cartilage morphology occur in the knee under conditions of partial load bearing. METHODS: The knees of 20 patients with Weber type B and type C fractures were examined using magnetic resonance imaging. The first scan was obtained shortly (mean +/- SD 3.2 +/- 3.0 days) after the injury, and a second scan was obtained 7 weeks later (mean +/- SD 50.7 +/- 5.5 days). The morphology (mean and maximum thickness, volume, and surface area) of the patellar, tibial, and femoral cartilage was determined from coronal and axial magnetic resonance images (fat-suppressed gradient-echo). RESULTS: Between week 0 and week 7, the cross-sectional area of the quadriceps muscle was reduced by 11% (P< 0.001). Changes in the mean (+/-SD) cartilage thickness ranged from -2.9 +/- 3.2% in the patella to -6.6 +/- 4.9% in the medial tibia. No significant change in cartilage morphology of the contralateral knee was observed. CONCLUSION: Results of this study demonstrate that in a post-ankle fracture model of partial load bearing, cartilage morphology in all knee compartments is subject to significant change. Changes in the femorotibial joint exceeded those in the patella, whereas no change was observed in the contralateral knee. These findings raise the question of whether cartilage is mechanically less competent and particularly vulnerable after states of partial or complete immobilization.  相似文献   
49.
BackgroundAfter an outbreak of the SARS-CoV-2 Beta variant in the district of Schwaz/Austria, vaccination with Comirnaty vaccine (BNT162b2 mRNA, BioNTech-Pfizer) had been offered to all adult inhabitants (≥ 16 years) in March 2021. This made Schwaz one of the most vaccinated regions in Europe at that time (70% of the adult population took up the offer). In contrast, all other Austrian districts remained with low vaccine coverage.AimWe studied whether this rapid mass vaccination campaign provided indirect protection to unvaccinated individuals such as children (< 16 years) living in the same district.MethodsTo study the effect of the campaign we used two complementary approaches. We compared infection rates among the population of children (< 16 years) in Schwaz with (i) the child population from similar districts (using the synthetic control method), and (ii) with the child population from municipalities along the border of Schwaz not included in the campaign (using an event study approach).ResultsBefore the campaign, we observed very similar infection spread across the cohort of children in Schwaz and the control regions. After the campaign, we found a significant reduction of new cases among children of −64.5% (95%-CI: −82.0 to −30.2%) relative to adjacent border municipalities (using the event study model). Employing the synthetic control method, we observed a significant reduction of −42.8% in the same cohort.ConclusionOur results constitute novel evidence of an indirect protection effect from a group of vaccinated individuals to an unvaccinated group.  相似文献   
50.
Although the pathogenesis of Hirschsprung's disease (HD) is not completely resolved, both the absence of nerve cells and the hypertrophy of nerve fascicles within the aganglionic colonic segment have been attributed to an abnormal intestinal microenvironment. Studies on animal models for HD revealed an altered ultrastructure of ingrowing nerve fascicles and abnormalities of basal laminae (BL). Therefore, the purpose of this study was to examine the ultrastructure of hypertrophied nerve fascicles in human HD with special reference to structural abnormalities of BL. Colonic specimens were obtained from patients with HD (n = 10) and controls (n = 5) and processed for electron-microscopical examination. Hypertrophied nerve fascicles were characterized by a prominent perineural sheath surrounded by large amounts of collagen bundles, a collagen-filled endoneurium, vasa nervorum and abundant glial cells of extraenteric ultrastructure, which were arranged in mono- or oligoaxonal units and frequently displayed different stages of myelination. As these ultrastructural characteristics resembled typical features of extrinsic nerves and were similar to those observed in subserosal nerves, the prominent intramural nerve fascicles were considered to be of extraenteric origin. Most likely their overabundance contributes to the functional obstruction of the terminal colon. Morphological abnormalities of BL encountered in the aganglionic colonic segment consisted of an extensive multilamination of BL surrounding glial processes and an irregular thickening of BL surrounding perineurocytes and smooth muscle cells of the muscularis mucosae. Similar alterations in BL have also been described in inherited peripheral and diabetic autonomic neuropathies and attributed to reactivated schwann cells. Thus, the overproduction of BL material within the hypertrophied nerve fascicles in HD may reflect an increased activity of proliferating glial cells. Since the smooth muscle cells of the muscularis mucosae showed abnormalities of BL similar to those observed in murine models for HD, it is suggestive that also in human HD the aganglionic colon is affected by a disturbed intestinal micro-environment impairing the neuronal colonisation and promoting the ingrowth of extrinsic nerves. The ultrastructurally observed alterations in BL of both neuronal and non-neuronal cells, as well as the increased amount of perineural and endoneural collagen provide further evidence that extracellular matrix components are abnormally distributed and overproduced within the bowel wall of patients affected by HD.  相似文献   
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