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51.
52.
BackgroundThe current understanding of ventilator efficiency variables during ramp exercise testing in the normal Japanese population is insufficient, and the responses of tidal volume (VT) and minute ventilation (V?E) to the ramp exercise test in the normal Japanese population are not known.MethodsA total of 529 healthy Japanese subjects aged 20–78 years underwent cardiopulmonary exercise testing using a cycle ergometer with ramp protocols. VT and V?E at rest, at anaerobic threshold, and at peak exercise were determined. The slope of V?E versus carbon dioxide (V?CO2) (V?E vs. V?CO2 slope), minimum V?E/V?CO2, and oxygen uptake efficiency slope (OUES) were determined.ResultsFor males and females in their 20 s, peak VT (VTpeak) was 2192 ± 376 and 1509 ± 260 mL (p < 0.001), peak V?E (V?Epeak) was 80.6 ± 18.7 and 57.7 ± 13.9 L/min (sex differences p < 0.001), the V?E vs. V?CO2 slope was 24.4 ± 3.2 and 25.7 ± 3.2 (p = 0.035), the minimum V?E/V?CO2 was 24.2 ± 2.3 and 27.0 ± 2.8 (p < 0.001), and the OUES was 2452 ± 519 and 1991 ± 315 (p < 0.001), respectively. VTpeak and V?Epeak decreased with age and increased with weight and height. The V?E vs. V?CO2 slope and minimum V?E/V?CO2 increased with age, while conversely, the OUES decreased with age.ConclusionsWe have established the normal range of VT and V?E responses, the V?E vs. V?CO2 slope, the minimum V?E/V?CO2, and the OUES for a healthy Japanese population. Some of these parameters were influenced by weight, height, sex, and age. These results provide useful reference values for interpreting the results of cardiopulmonary exercise testing in cardiac patients.  相似文献   
53.
Since a variety of cell intrinsic and extrinsic molecular abnormalities cooperatively promote tumor formation in multiple myeloma (MM), therapeutic approaches that concomitantly target more than one molecule are increasingly attractive. We herein demonstrate the anti-myeloma effect of a cephalotaxus alkaloid, homoharringtonine (HHT), an inhibitor of protein synthesis, through the induction of apoptosis. HHT significantly reduced Mcl-1, a crucial protein involved in myeloma cell survival, in all three myeloma cell lines examined, whereas certain BH3-only proteins, such as Bim, Bik, and Puma, remained unchanged following HHT treatment, and their expression levels depended on the cell type. HHT also reduced the levels of c-FLIP(L/S), activated caspase-8, and induced active truncated-Bid. Thus, HHT-induced apoptosis appears to be mediated via both intrinsic and extrinsic apoptosis pathways, and the resultant imbalance between BH3-only proteins and Mcl-1 may be pivotal for apoptosis by HHT. In addition, HHT treatment resulted in reduced levels of beta-catenin and XIAP proteins, which also contribute to disease progression and resistance to chemotherapy in MM. In combination, HHT enhanced the effects of melphalan, bortezomib, and ABT-737. These results suggest that HHT could constitute an attractive option for MM treatment though its ability to simultaneously target multiple tumor-promoting molecules.  相似文献   
54.
STUDY OBJECTIVES: Following the development of the Caribbean Guidelines for Asthma Care, we examined the utilization of inhaled medications in asthmatic patients in Trinidad, West Indies. SETTING: Chest Clinic, Ministry of Health, Trinidad. PARTICIPANTS: Physician-diagnosed asthmatic patients who attended the Chest Clinic between July 1998 and August 2000. MEASUREMENTS AND RESULTS: A consecutive sample of patients who were > 7 years of age (n = 402) was interviewed about compliance with, understanding of, and use of inhaler medication. The inhaler technique of these patients was directly observed. Inhaled steroid therapy was prescribed in 83% of patients but were prescribed the least in elderly patients (63%) and children (62%). Salbutamol was prescribed in 98% of patients, and ipratropium and sodium cromoglycate were selectively prescribed in elderly men and children, respectively. Only 33% of patients used the inhaler correctly, and children and the elderly were the least efficient in its use. The use of a spacer device was advised in 19% of patients, including only 6% of the elderly patients. Explanations for different inhaler therapies were given to 62% of patients, and 53% of patients could describe these reasons. The reported 40% noncompliance rate among patients in the sample was primarily a result of long waiting periods at the pharmacy (58%) and the personal cost incurred on purchasing the medication (52%). CONCLUSIONS: Educating patients, with a focus on children and the elderly, in inhaler techniques and reinforcing understanding of asthma medications can improve asthma management in Trinidad. Asthma caregivers in the Caribbean should ensure the appropriate dissemination of the guidelines and should outline strategies for their implementation.  相似文献   
55.
Evidence for association between serum total homocysteine (tHcy) level and cardiovascular disease is limited in Asian populations. We conducted a nested case-control study under JACC Study. A total of 39,242 subjects aged 40-79 years provided serum samples at baseline surveys between 1988 and 1990. Control subjects were selected by matching for sex, age, community and year of serum storage. Serum tHcy levels were measured by high-performance liquid chromatography. During the 10-year follow-up, there were 444 deaths due to total cardiovascular disease, including 310 total stroke (131 hemorrhage and 101 ischemic strokes) and 134 coronary heart diseases. The risks of mortality from ischemic stroke, coronary heart disease, and total cardiovascular disease were significantly higher in individuals with the highest serum tHcy quartile (>or=15.3micromol/L) than in those with the lowest quartile (<10.5micromol/L); the respective multivariable odds ratios (95% CI) were 4.35 (1.12-16.9), 3.40 (1.17-9.86), and 1.68 (1.02-2.77). The multivariable odds ratios associated with a 5-micromol/L increase in tHcy were 1.49 (1.01-2.18), 2.01 (1.21-3.35), and 1.15 (1.00-1.32), respectively. High serum tHcy levels were associated with increased mortality from ischemic stroke, coronary heart disease and total cardiovascular disease among Japanese.  相似文献   
56.
ABSTRACT

Half of HIV-positive persons in Russia are on antiretroviral therapy (ART), and only 27% are virally suppressed. A feasibility pilot intervention to mobilize social capital resources for HIV care support was conducted in St. Petersburg. Out-of-care or ART-nonadherent HIV-positive persons (n?=?24) attended a five-session intervention to increase access social capital resources (i.e., family, friends, or providers) to mobilize supports for entering care, initiating care, and adhering to ART. HIV care indicators were assessed at baseline, an immediate followup (FU-1), and 6-month followup (FU-2) points. At FU-1, participants more frequently discussed their care experiences with others, verifying the intervention’s mechanism of action. Participants increased in scales of medication taking adherence (p?=?0.002, FU-1; p?=?0.011, FU-2), self-efficacy (p?=?0.042; FU-1), and outcome expectancies (p?=?0.016, FU-2). Among persons not on ART, HIV Medication Readiness scale scores increased at FU-1 (p?=?0.032) but became attenuated at FU-2. Participants tended to more frequently keep care appointments (79%, baseline to 90%, FU-1, p?=?0.077); to have undetectable viral load (54%, baseline to 74%, FU-2; p?=?0.063); and to have fewer past-month days with delayed or incomplete medication doses (7.8, baseline to 4.2, FU-1; p?=?0.084). This novel social capital intervention is promising for improving HIV care-related outcomes and warrants a full-scale evaluation.  相似文献   
57.
Seasonal influenza vaccination elicits a diminished adaptive immune response in the elderly, and the mechanisms of immunosenescence are not fully understood. Using Ig-Seq, we found a marked increase with age in the prevalence of cross-reactive (CR) serum antibodies that recognize both the H1N1 (vaccine-H1) and H3N2 (vaccine-H3) components of an egg-produced split influenza vaccine. CR antibodies accounted for 73% ± 18% of the serum vaccine responses in a cohort of elderly donors, 65% ± 15% in late middle-aged donors, and only 13% ± 5% in persons under 35 years of age. The antibody response to non-HA antigens was boosted by vaccination. Recombinant expression of 19 vaccine-H1+H3 CR serum monoclonal antibodies (s-mAbs) revealed that they predominantly bound to non-HA influenza proteins. A sizable fraction of vaccine-H1+H3 CR s-mAbs recognized with high affinity the sulfated glycans, in particular sulfated type 2 N-acetyllactosamine (Galβ1-4GalNAcβ), which is found on egg-produced proteins and thus unlikely to contribute to protection against influenza infection in humans. Antibodies against sulfated glycans in egg-produced vaccine had been identified in animals but were not previously characterized in humans. Collectively, our results provide a quantitative basis for how repeated exposure to split influenza vaccine correlates with unintended focusing of serum antibody responses to non-HA antigens that may result in suboptimal immunity against influenza.  相似文献   
58.
Recently, it has been shown that increased level of LDL-containing circulating immune complexes (LDL-CIC) possess high diagnostic significance in clinically manifested atherosclerosis, but little is known about its diagnostic and prognostic significance in early atherosclerosis. Two-years prospective study was performed in 98 asymptomatic men aged 40–74. The rate of atherosclerosis progression was estimated by high-resolution B-mode ultrasonography as the increase in intima-media thickness (IMT) of common carotid arteries. The patients with elevated baseline levels of LDL-CIC were characterized by significantly higher levels of total and LDL cholesterol as well as significantly increased mean IMT of common carotid arteries. Among all baseline lipid parameters, only LDL-CIC and LDL cholesterol were contingent with the extent of early carotid atherosclerosis (p?=?0.042 and p?=?0.049, respectively) and had the highest levels of relative risk and odds ratio. During the follow up, significant IMT increase was registered in 53.1 % (n?=?52) patients, IMT significant reduction was observed in 21.4 % (n?=?21) patients. The increased levels of LDL-CIC, total serum cholesterol and LDL cholesterol had similar prognostic significance with the respect of atherosclerosis progression. The normal level of LDL-CIC (below than 16.0 μg/ml) was the only lipid parameter that predicted the absence of carotid atherosclerosis progression for two following years at prognostic value of 78.3 %. The results of the study allow assuming that LDL-CIC level may be employed not only as a marker of early atherosclerosis, but also has a sufficient prognostic value for clinical implications.  相似文献   
59.
Objective: We report two cases of atypical femoral fracture (AFF) in patients with cancer.Patients: Two patients, a 53-year-old woman with breast cancer and a 77-year-old man with prostate cancer, could not walk after being injured in a fall. They used bone-modifying agents (BMA) for the prevention of bone metastasis for three and four years, respectively.Results: Intramedullary nails were placed to fix the femoral fractures in each patient. Neither of them had pathological metastatic femoral fractures based on fracture site specimens; however, severe suppression of bone turnover at the fracture site was suspected. Both patients could ambulate with a T-cane and were free of hip pain after surgery. Radiographs showed no callus formation at the fracture site.Conclusion: Based on the two cases of AFF in patients with cancer related to BMA use, we should consider that the incidence of AFF may be associated with long-term BMA use.  相似文献   
60.
Journal of Muscle Research and Cell Motility - Two single mutations, R694N and E45Q, were introduced in the beta isoform of human cardiac myosin to remove permanent salt bridges E45:R694 and...  相似文献   
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