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1.
The capacity of live or inactivated respiratory syncytial virus (RSV) to induce B-cell memory in respiratory-associated lymphoid tissues of mice was examined. Eight weeks after primary inoculation with either live or inactivated RSV, adult BALB/c mice were challenged with 4 × 105 PFU of RSV. Protection from viral shedding and mucosal production of RSV-specific antibodies were examined at various time points after challenge. We found that primary immunization with live, but not inactivated, RSV induced complete and durable protection upon challenge within the upper and lower respiratory tract. Also, primary immunization with live, but not inactivated, RSV enhanced the production of mucosal RSV-specific immunoglobulin A (IgA) upon challenge. Secondary mucosal IgA responses were characterized by (i) the early production of mucosal IgA by B cells that reside in organized nasal-associated lymphoid tissues, cervical lymph nodes, and bronchial lymph nodes, and (ii) the subsequent production of RSV-specific IgA by mucosal effector tissues, such as the tracheal lamina propria and lung. These findings suggest that primary infection of mice with live RSV might induce mucosal IgA-committed memory B cells. A greater understanding of the characteristics of RSA-specific mucosal memory B cells may facilitate the development of an RSV vaccine.  相似文献   
2.
The human non-classical MHC class I molecule HLA-E is a ligand for both an inhibitory NK cell receptor (CD94/NKG2A) and an activating receptor (CD94/NKG2C). To identify HLA-E surface recognized by both receptors, especially to determine if both receptors recognize the same epitope, we made a series of individually Ala-substituted HLA-E proteins and analyzed their binding to CD94/NKG2A orCD94/NKG2C. Eight HLA-E mutations that significantly impaired HLA-E binding to CD94/NKG2A are all found in the top of alpha1/alpha2 domain of HLA-E. These results suggest that CD94/NKG2A binds a HLA-E surface equivalent to a NKG2D binding site on MICA. Of the eight mutations that impaired HLA-E binding to CD94/NKG2A, six significantly impaired HLA-E binding to CD94/NKG2C suggesting that CD94/NKG2C also binds a similar surface of HLA-E. Unexpectedly, the two HLA-E mutations (D69A and H155A) selectively abrogated HLA-E binding to CD94/NKG2A, not largely affected CD94/NKG2C. These results indicate that a mostly shared, but partly distinct set of HLA-E residues is discriminated by the two receptors.  相似文献   
3.
The gut microbiota is closely related to good health; thus, there have been extensive efforts dedicated to improving health by controlling the gut microbial environment. Probiotics and prebiotics are being developed to support a healthier intestinal environment. However, much work remains to be performed to provide effective solutions to overcome individual differences in the gut microbial community. This study examined the importance of nutrients, other than dietary fiber, on the survival of gut bacteria in high-health-conscious populations. We found that vitamin B1, which is an essential nutrient for humans, had a significant effect on the survival and competition of bacteria in the symbiotic gut microbiota. In particular, sufficient dietary vitamin B1 intake affects the relative abundance of Ruminococcaceae, and these bacteria have proven to require dietary vitamin B1 because they lack the de novo vitamin B1 synthetic pathway. Moreover, we demonstrated that vitamin B1 is involved in the production of butyrate, along with the amount of acetate in the intestinal environment. We established the causality of possible associations and obtained mechanical insight, through in vivo murine experiments and in silico pathway analyses. These findings serve as a reference to support the development of methods to establish optimal intestinal environment conditions for healthy lifestyles.  相似文献   
4.
The influenza A/H1N1 2009 epidemic has spread to many countries since 2009, including Japan. We report an immune‐competent child involving rhabdomyolysis and compartment syndrome associated with influenza A/H1N1 2009. The patient was demonstrated rhabdomyolysis with myoglobinuria, hyperkalemia, cardiac dysfunction and compartment syndrome that arose during convalescence from influenza A/H1N1 2009 infection. Although RT‐PCR of muscle tissue yielded negative results for influenza A/H1N1 2009 RNA and no viral positive‐antigen cells were detected in the muscle lesions, the clinical picture suggested rhabdomyolysis associated with influenza A/H1N1. Rhabdomyolysis should be considered in the evaluation of muscle symptoms such as myalgia associated with novel influenza A/H1N1 2009 virus infection, particularly in critically ill patients.  相似文献   
5.
The fluorescence spectral fingerprint, also known as the excitation-emission matrix (EEM), is used to assess and visualize therapeutic drug photodegradation in combination with chemometrics. Examination of EEM-parallel factor analysis (PARAFAC) data showed that an individual component was easily separated from a mixture of photogenerated products of a heterocyclic pharmacophore, in this case, phenothiazine drugs (PTZs). Detailed investigations of both structure–EEM relationships and kinetics revealed that the components extracted from EEM–PARAFAC could be quantitatively attributed to such photogenerated products as phenothiazine sulfoxide and carbazole derivatives. EEM in combination with principal component analysis (PCA) could be used as a mapping tool to visualize information of the photodegradation process of PTZs. We also assessed the photostability of various types of PTZs containing side chains by using validated EEM–PARAFAC methodology.

Drug quality and assurance changes with time under the influence of a variety of environmental factors, such as light, temperature, and moisture.  相似文献   
6.
BackgroundHospitalist turnover is exceedingly high, placing financial burdens on hospital medicine groups (HMGs). Following training, many begin their employment in medicine as early-career hospitalists, the majority being millennials.ObjectiveTo understand what elements influence millennial hospitalists’ recruitment and retention.DesignWe developed a survey that asked participants to rate the level of importance of 18 elements (4-point Likert scale) in their decision to choose or remain at an HMG.ParticipantsThe survey was electronically distributed to hospitalists born in or after 1982 across 7 HMGs in the USA.Main MeasuresElements were grouped into four major categories: culture of practice, work-life balance, financial considerations, and career advancement. We calculated the means for all 18 elements reported as important across the sample. We then calculated means by averaging elements within each category. We used unpaired t-tests to compare differences in means for categories for choosing vs. remaining at an HMG.Key ResultsOne hundred forty-four of 235 hospitalists (61%) responded to the survey. 49.6% were females. Culture of practice category was the most frequently rated as important for choosing (mean 96%, SD 12%) and remaining (mean 96%, SD 13%) at an HMG. The category least frequently rated as important for both choosing (mean 69%, SD 35%) and remaining (mean 76%, SD 32%) at an HMG was career advancement. There were no significant differences between respondent gender, race, or parental status and ratings of elements for choosing or remaining with HMGs.ConclusionCulture of practice at an HMG may be highly important in influencing millennial hospitalists’ decision to choose and stay at an HMG. HMGs can implement strategies to create a millennial-friendly culture which may help improve recruitment and retention.KEY WORDS: Hospitalist, Hospital medicine group (HMG), Recruitment, Retention, Culture of practice, Millennial  相似文献   
7.
8.
The purpose of this study is to determine the incidence, clinical characteristics and risk factors of postradiation pelvic insufficiency fracture (PIF) in women with uterine cervical cancer. We reviewed the medical records of 126 patients who received definitive radiotherapy (RT) for uterine cervical cancer between 2003 and 2009 at our institution. Among them, 99 patients who underwent at least one computed tomography (CT) or magnetic resonance imaging of the pelvis during their follow-up at more than 6 months were included in this analysis. The relationship between the incidence of PIF and several patient- and treatment-related factors was analyzed. The median follow-up period was 21 months. Of the 126 patients, 33 (with a total of 50 lesions) were diagnosed with PIF. The 2-year cumulative incidence was 32%. Univariate analysis showed that age ≥70 years (P= 0.0010), postmenopausal state (P = 0.0013), and lower CT density of bone and bone marrow (P= 0.020) significantly related to PIF. In a multivariate analysis, of the 59 patients whose CT densities were evaluable, lower CT density was the only significant factor associated with PIF (P = 0.0026). In conclusion, postradiation PIFs were detected in a considerable number of patients after definitive RT for cervical cancer. Predisposing factors were older age, postmenopausal state, and decreased density of bone and bone marrow on CT.  相似文献   
9.
The patient was a 39-year-old woman admitted with complaints of fever, clubbed fingers and arthralgia. A chest roentgenogram and chest computed tomographic scan revealed a mass in the left lower lobe. Transbronchial lung biopsy was performed, and a diagnosis of moderately differentiated adenocarcinoma was made. Physical examination confirmed finger clubbing in both hands. Bone scintigram showed marked accumulation of 99mTc-MDP in the long bones, bones of the elbows, and patellae. These findings yielded a diagnosis of pulmonary hypertrophic osteoarthropathy associated with primary lung cancer in young adult. The patient had fever and disturbance of gait of arthralgia on admission, and was treated with an oral non-steroidal anti-inflammation drug (NSAID). Advanced non small cell lung cancer (clinical stage T2 N3 M1, Stage IV) was then diagnosed. Gefitinib was administered after EGFR mutation was found in the tumor specimen. NSAID therapy alleviated the fever and arthralgia. After starting gefitinib and discontinuing the NSAID, She had kept a remission of rational symptom with cytoreductive effect. The abnormal findings of bone scintigrams subsequently disappeared and the patient's serum ICTP dropped.  相似文献   
10.
The objective of this study was to examine the contribution of endurance fitness and visceral fat accumulation on the prevalence of metabolic syndrome in Japanese male patients with either an impaired glucose tolerance (IGT) or type 2 diabetes mellitus (DM). The subjects of this cross-sectional study consisted of 135 Japanese male patients with either IGT or type 2 DM who had not taken any medication or intervention. They were classified into three fitness categories (low, moderate, and high) based on the tertiles of their maximal oxygen uptake ( [Formula: see text] O(2)max) predicted by the Astrand nomogram using a cycle ergometer. Metabolic syndrome was defined based on the WHO criteria. The visceral fat area (VFA) was determined using a computed tomography scan. The age- and VFA-adjusted odds ratio was 3.49 (95% CI, 1.13-10.82) for subjects in the low fitness category in comparison to those in the high fitness category. We calculated the odds ratio for the prevalence of metabolic syndrome in the nine categories classified based on the three VFA and three [Formula: see text] (2)max levels. In Moderate- and Low- [Formula: see text] (2) max categories, the odds ratios increased in line with increases in the VFA level. The highest odds ratios were observed in the low fitness and high visceral fat group. In the High- [Formula: see text] O(2)max category, no significant odds ratios were observed in the Moderate- and High-VFA categories. These results indicate that a high degree of cardiorespiratory fitness positively contributed to the low prevalence of metabolic syndrome in Japanese male patients with IGT and type 2 DM.  相似文献   
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