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61.

Objective

To investigate the kinematic and myographic effects of weighted wrist cuffs on individuals with Parkinson disease (PD) during a reaching task.

Design

Cross-sectional study.

Setting

Biomechanics research laboratory.

Participants

Individuals (N=39) with PD (n=19) and healthy age-matched control subjects (n=20).

Interventions

Participants were instructed to reach and grasp a can at a distance of 80% of their arm length without a wrist cuff, while wearing separate 0.5- and 1.0-kg wrist cuffs, and subsequently without a wrist cuff.

Main Outcome Measures

Movement time, kinematic, and electromyographic data were recorded during all reach and grasp movements. Four end point coordinate strategy variables, 3 joint recruitment variables, and 2 co-contraction indices were derived from the raw data for analysis.

Results

Significant interaction effects were found in the trunk and index finger movement time as the weight of the cuff increased from 0.5 to 1.0kg. The group of individuals with PD showed decreased movement times in both instances, whereas the control group showed increased movement times as the weight of the wrist cuff increased from baseline to 0.5 and 1.0kg. No group difference was observed in the co-contraction index of the upper arm and forearm.

Conclusions

Adoption of weighted wrist cuffs in the clinic should be cautiously undertaken because compensatory movements may be induced in the trunk of individuals with PD.  相似文献   
62.

Background and Purpose

μ-Opioid receptors, pro-opiomelanocortin and pro-enkephalin are highly expressed in the nucleus tractus solitarii (NTS) and μ receptor agonists given to the NTS dose-dependently increased BP. However, the molecular mechanisms of this process remain unclear. In vitro, μ receptors heterodimerize with α2A-adrenoceptors. We hypothesized that α2A-adrenoceptor agonists would lose their depressor effects when their receptors heterodimerize in the NTS with μ receptors.

Experimental Approach

We microinjected μ-opioid agonists and antagonists into the NTS of rats and measured changes in BP. Formation of μ receptor/α2A-adrenoceptor heterodimers was assessed with immunofluorescence and co-immunoprecipitation methods, along with proximity ligation assays.

Key Results

Immunofluorescence staining revealed colocalization of α2A-adrenoceptors and μ receptors in NTS neurons. Co-immunoprecipitation revealed interactions between α2A-adrenoceptors and μ receptors. In situ proximity ligation assays confirmed the presence of μ receptor/α2A-adrenoceptor heterodimers in the NTS. Higher levels of endogenous endomorphin-1 and μ receptor/α2A-adrenoceptor heterodimers were found in the NTS of hypertensive rats, than in normotensive rats. Microinjection of the μ receptor agonist [D-Ala2, MePhe4, Gly5-ol]-enkephalin (DAMGO), but not that of the α2A-adrenoceptor agonist guanfacine, into the NTS of normotensive rats increased μ receptor/α2A-adrenoceptor heterodimer formation and BP elevation. The NO-dependent BP-lowering effect of α2A-adrenoceptor agonists was blunted following increased formation of μ receptor/α2A-adrenoceptor heterodimers in the NTS of hypertensive rats and DAMGO-treated normotensive rats.

Conclusions and Implications

Increases in endogenous μ receptor agonists in the NTS induced μ receptor/α2A-adrenoceptor heterodimer formation and reduced the NO-dependent depressor effect of α2A-adrenoceptor agonists. This process could contribute to the pathogenesis of hypertension.  相似文献   
63.
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymopathic disease in Taiwan. The mass neonatal screening of G6PD deficiency by fluorometric spot test in Taiwan was started with a pilot program in 1984. The nationwide screening was started on July 1, 1987, and a follow-up system comprising of eighteen referral hospitals, including outlying islands, was organized for confirmatory test, medical care and genetic counseling. From July 1987 to December 1997, 2,971,192 heel blood samples collected on filter paper from 1,143 delivery units were screened by four neonatal screening centers. 46,570 cases were confirmed as G6PD deficiency is estimated to be around 2.1% (male 3.1%, female 0.9%) in Taiwan. The coverage rate of neonatal screening was 99% in 1997. To assess the reliability of the confirmatory test, an external quality assurance (QA) program for G6PD assay was developed. Periodically, 3 or 5 lyophilized quality control materials with different activities of G6PD were sent to each referral hospital by speed post delivery in dry ice. From January 1988 to June 1998, 85 QA services were performed. Two hundred and seven (13.5%) abnormal QA results were found, which were attributed to clerk (11.6%), procedural (16.4%), and instrumental errors (47.3%). In aid to confirm G6PD deficiency, a method to detect the G6PD mutation by using the dried blood samples was developed. The frequencies of the mutant alleles in Taiwan were determined to be 46.8% (1376G > T), 16.2% (1388G > A), 7.9% (95A > G), 6.5% (493A > G), 5.6% (392G >T), 4.6% (1024C > T), 0.5% (487G > A) and 0.5% (519C > G), respectively.  相似文献   
64.
CD34+-selected peripheral blood progenitor cells (PBPCs) may not only reduce contaminated tumor cells but also compromise immunologic reconstitution and increase incidence of infections after transplantation. We analyzed the incidence of virus reactivation in CD34+-selected PBPCs autologous transplantation. From December 2001 to December 2004, ten high-risk aggressive non-Hodgkin’s lymphoma (NHL) patients were enrolled in a program of high-dose chemotherapy plus autologous CD34+-selected PBPCs support. Viral screening studies, including clinical symptoms, physical examinations, hepatitis B virus (HBV)-DNA, cytomegalovirus (CMV)-polymerase chain reaction (PCR), rapid diagnosis of fluorescent antibody stain for herpes-simplex virus (HSV), and viral culture from blood, fluid or tissue were performed weekly during the first 3 months and then monthly for 1 year. Two of four patients (50%) who were HBV carriers developed HBV reactivation. The other two HBV carriers who received prophylactic lamivudine therapy did not develop HBV reactivation. Two patients (20%) developed cytomegalovirus (CMV) infection, and three patients (30%) developed HSV infection in total ten serum-positive patients. The possibility of virus reactivation might increase in NHL patients undergoing autologous CD34+-selected PBPC transplantation. Administering prophylactic antivirus therapy and closely following patient’s clinical viral complications should be considered.  相似文献   
65.
BACKGROUND: Earlier phase 1 and 2 studies have shown that regadenoson has desirable features as a stress agent for myocardial perfusion imaging. METHODS AND RESULTS: This multicenter, double-blinded phase 3 trial involved 784 patients at 54 sites. Each patient underwent 2 sets of gated single photon emission computed tomography myocardial perfusion imaging studies: an initial qualifying study with adenosine and a subsequent randomized study with either regadenoson (2/3 of patients) or adenosine. Regadenoson was administered as a rapid bolus (<10 seconds) of 400 mug. The primary endpoint was to demonstrate noninferiority by showing that the difference in the strength of agreement in detecting reversible defects, based on blinded reading, between sequential adenosine-regadenoson images and adenosine-adenosine images, lay above a prespecified noninferiority margin. Other prospectively defined safety and tolerability comparisons and supporting analyses were also performed. The average agreement rate based on the median of 3 independent blinded readers was 0.63 +/- 0.03 for regadenoson-adenosine and 0.64 +/- 0.04 for adenosine-adenosine-a 1% absolute difference with the lower limit of the 95% confidence interval lying above the prespecified noninferiority margin. Side-by-side interpretation of regadenoson and adenosine images provided comparable results for detecting reversible defects. The peak increase in heart rate was greater with regadenoson than adenosine, but the blood pressure nadir was similar. A summed symptom score of flushing, chest pain, and dyspnea was less with regadenoson than adenosine (P = .013). CONCLUSIONS: This phase 3 trial shows that regadenoson provides diagnostic information comparable to a standard adenosine infusion. There were no serious drug-related side effects, and regadenoson was better tolerated than adenosine.  相似文献   
66.
T cells are involved in control of coronavirus disease 2019 (COVID-19), but limited knowledge is available on the relationship between antigen-specific T cell response and disease severity. Here, we used flow cytometry to assess the magnitude, function, and phenotype of SARS coronavirus 2–specific (SARS-CoV-2–specific) CD4+ T cells in 95 hospitalized COVID-19 patients, 38 of them being HIV-1 and/or tuberculosis (TB) coinfected, and 38 non–COVID-19 patients. We showed that SARS-CoV-2–specific CD4+ T cell attributes, rather than magnitude, were associated with disease severity, with severe disease being characterized by poor polyfunctional potential, reduced proliferation capacity, and enhanced HLA-DR expression. Moreover, HIV-1 and TB coinfection skewed the SARS-CoV-2 T cell response. HIV-1–mediated CD4+ T cell depletion associated with suboptimal T cell and humoral immune responses to SARS-CoV-2, and a decrease in the polyfunctional capacity of SARS-CoV-2–specific CD4+ T cells was observed in COVID-19 patients with active TB. Our results also revealed that COVID-19 patients displayed reduced frequency of Mycobacterium tuberculosis–specific CD4+ T cells, with possible implications for TB disease progression. These results corroborate the important role of SARS-CoV-2–specific T cells in COVID-19 pathogenesis and support the concept of altered T cell functions in patients with severe disease.  相似文献   
67.
ObjectivePreterm infants receive long-term parenteral nutrition (PN) for gastrointestinal immaturity. This study aimed to determine if mixed lipid emulsions containing fish oil decrease the incidence of PN-associated cholestasis by reducing oxidative stress and providing an anti-inflammatory effect.MethodsThis retrospective cohort study enrolled 399 very low birth weight premature infants (gestational age ≤32 weeks) between January 2009 and November 2017 at a single neonatal intensive care unit. Preterm infants received total PN with either mixed lipid emulsion including fish oil (SMOFlipid®, n = 195) or soybean oil-based lipid emulsion (Lipovenoes®, n = 204) for at least 7 days. We compared the outcomes of PN-associated cholestasis, comorbidities, and mortality between the groups.ResultsThe incidence of PN-associated cholestasis was significantly lower in the SMOFlipid group than in the Lipovenoes group. The duration to full feeding days was significantly shorter in the SMOFlipid group compared with the Lipovenoes group. Relevant complications, such as severe retinopathy of prematurity and bronchopulmonary dysplasia, were also significantly reduced in the SMOFlipid group compared with the Lipovenoes group.ConclusionIn premature infants, PN with fish oil-based lipid emulsions is associated with a lower incidence of PN-associated cholestasis compared with soybean oil-based lipid emulsions.  相似文献   
68.
69.
Rubella has been listed as a mandatory notifiable disease in Taiwan since 1988. Because of high coverage rates with an effective vaccine, rubella cases have decreased dramatically in Taiwan since 1994. However, rubella outbreaks still occur due to imported transmission. Five large clusters were detected in Taiwan from 2007 to 2011. In 2007, one cluster was caused by rubella genotype 1E viruses that were imported from Vietnam, whereas another cluster was caused by genotype 2B viruses and was untraceable. In 2008, two clusters were caused by different lineages of genotype 1E viruses that were imported from Malaysia. In 2009, a cluster that was caused by genotype 2B viruses was associated with imported cases from Vietnam. The rubella viruses from 124 confirmed cases from 2005 to 2011 were characterized, and the data revealed that these viruses were distributed in the following four genotypes: 1E (n = 56), 1h (n = 1), 1j (n = 4), and 2B (n = 63). Of these viruses, 93 (75%) were associated with imported cases, and 43 of 56 genotype 1E viruses were associated with imported cases from China, Vietnam, Malaysia, and Indonesia. One genotype 1h virus was imported from Belarus, and three of four genotype 1j viruses were imported from the Philippines. Of 63 rubella genotype 2B viruses, 46 were imported from Vietnam, Thailand, Malaysia, China, Germany, and South Africa. Molecular surveillance allows for the differentiation of circulating rubella viruses and can be used to investigate transmission pathways, which are important to identify the interruption of endemic virus transmission. J. Med. Virol. 85:745–753, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
70.
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