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991.
Yicong Yin Danchen Wang Chaochao Ma Songlin Yu Shaowei Xie Qian Cheng Ling Qiu 《Journal of clinical laboratory analysis》2021,35(4)
BackgroundVitamins A and E play important roles in sustaining life activities and maintaining a good physical condition. However, most people, particularly the elderly, experience micronutrient deficiencies. This study aimed to establish reference intervals (RIs) for vitamins A and E in Chinese elderly people using a liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) method.MethodsA total of 356 apparently healthy individuals aged ≥64 years who underwent health checkups were randomly selected for the study. Vitamin A and E levels were measured using LC‐MS/MS. The effect of sex on vitamin A and E levels was evaluated, and RIs were established using a parametric method.ResultsFemales showed significantly higher levels of vitamin E than males (p < 0.05). However, no significant sex‐specific difference was observed with vitamin A levels. The RI for vitamin A in the elderly was 0.283–0.730 mg/L. For vitamin E, the RIs were 4.39–15.63, 4.51–16.14, and 4.41–14.67 mg/L for the total, female, and male participants, respectively. In multiple linear regression, alanine aminotransferase, glutamyl transpeptidase, urea, glucose, and uric acid levels increased with increasing vitamin A levels (p < 0.05), and total cholesterol and low‐density lipoprotein cholesterol levels increased with increasing vitamin E levels (p < 0.05). Direct bilirubin levels decreased with increasing vitamin E levels (p < 0.05).ConclusionsThis study established RIs for vitamins A and E in Chinese elderly individuals using an LC‐MS/MS method. We also found that females had significantly higher vitamin E levels than males. The findings could provide a scientific basis for interpreting vitamin status in the elderly. 相似文献
992.
993.
Xia Xie Mi Tang Asher Kahn-Krell Kele Qin Jinfu Yang Chengming Fan 《The Journal of international medical research》2021,49(3)
Patients with a large congenital atrial septal defect (ASD) traditionally have the ASD repaired at the preschool age. Unfortunately, insufficient education of patients regarding medical science and clinical recommendations can lead to delayed therapy, resulting in complications during adulthood. We report a rare case of a large congenital ASD in a 20-year-old man. Echocardiography showed a 67-mm ostium secundum defect and moderate mitral and tricuspid regurgitation. The patient underwent transthoracic ASD repair along with mitral and tricuspid valvuloplasty. This report emphasizes the importance of educating patients about congenital malformations and potential interventions in developing countries, particularly in rural communities. 相似文献
994.
995.
Channakeshava S. Umeshappa Roopa H. Nanjundappa Yufeng Xie Andrew Freywald Qingyong Xu Jim Xiang 《Immunology》2013,138(4):298-306
Increased CD8+ T‐cell precursor frequency (PF) precludes the requirement of CD4+ helper T (Th) cells for primary CD8+ cytotoxic T‐lymphocyte (CTL) responses. However, the key questions of whether unhelped CTLs generated at higher PF are functional effectors, and whether unhelped CTLs can differentiate into functional memory cells at higher PF are unclear. In this study, ovalbumin (OVA) ‐pulsed dendritic cells (DCOVA) derived from C57BL/6, CD40 knockout (CD40?/?) or CD40 ligand knockout (CD40L?/?) mice were used to immunize C57BL/6, Iab?/?, CD40?/? or CD40L?/? mice, whose PF was previously increased with transfer of 1 × 106 CD8+ T cells derived from OVA‐specific T‐cell receptor (TCR) transgenic OTI, OTI(CD40?/?) or OTI(CD40L?/?) mice. All the immunized mice were then assessed for effector and memory CTL responses. Following DC immunization, relatively comparable CTL priming occurred without CD4+ T‐cell help and Th‐provided CD40/CD40L signalling. In addition, the unhelped CTLs were functional effectors capable of inducing therapeutic immunity against established OVA‐expressing tumours. In contrast, the functional memory development of CTLs was severely impaired in the absence of CD4+ T‐cell help and CD40/CD40L signalling. Finally, unhelped memory CTLs failed to protect mice against lethal tumour challenge. Taken together, these results demonstrate that CD4+ T‐cell help at higher PF, is not required for effector CTL priming, but is required for functional memory CTL development against cancer. Our data may impact the development of novel preventive and therapeutic approaches in cancer patients with compromised CD4+ T‐cell functions. 相似文献
996.
In epilepsy diagnosis or epileptic seizure detection, much effort has been focused on finding effective combination of feature extraction and classification methods. In this paper, we develop a wavelet-based sparse functional linear model for representation of EEG signals. The aim of this modeling approach is to capture discriminative random components of EEG signals using wavelet variances. To achieve this goal, a forward search algorithm is proposed for determination of an appropriate wavelet decomposition level. Two EEG databases from University of Bonn and University of Freiburg are used for illustration of applicability of the proposed method to both epilepsy diagnosis and epileptic seizure detection problems. For this data considered, we show that wavelet-based sparse functional linear model with a simple classifier such as 1-NN classification method leads to higher classification results than those obtained using other complicated methods such as support vector machine. This approach produces a 100 % classification accuracy for various classification tasks using the EEG database from University of Bonn, and outperforms many other state-of-the-art techniques. The proposed classification scheme leads to 99 % overall classification accuracy for the EEG data from University of Freiburg. 相似文献
997.
998.
Xiuqin Ma Ruhua Chen Xiufang Liu Jin Xie Keyun Si Lirong Duan 《African journal of traditional, complementary, and alternative medicines》2013,10(3):442-448
The current study aims to investigate the effects of matrine on the JAK-STAT signaling transduction pathways in bleomycin (BLM)-induced pulmonary fibrosis (PF) and to explore its action mechanism. A total of 72 male C57BL/6 mice were randomized into the control, model, and treatment groups. PF models were established by instilling BLM intratracheally. The treatment group was given daily matrine through gastric lavage. Six mice were sacrificed in each group at 3, 7, 14, and 28 days. The lung tissues were observed using hematoxylin-eosin staining. The expression of JAK, STAT1, and STAT3 was observed using immunohistochemistry and then determined using real-time polymerase chain reaction. Alveolitis and PF significantly improved in the treatment group compared with the model group (P < 0.05). The expression of JAK, STAT1, and STAT3 in the model group increased at day 7, peaked at day 14 and then decreased, but the expression was still higher than that in the control group at day 28 (P < 0.05). The three indices in the treatment group were significantly lower than those in the model group at any detection time point (P < 0.05). PF causes high expression of JAK, STAT1, and STAT3. Matrine exerts an anti-PF effect by inhibiting the JAK-STAT signaling transduction pathways. 相似文献
999.
AbstractObjectives: To develop a nomogram to evaluate the risk of urinary tract infections (UTI) in patients with neurogenic bladder (NGB)Methods: A retrospective analysis was conducted on 337 patients with NGB admitted to three hospitals. Collected data included clinical symptoms, patients’ general characteristics, laboratory examinations and imaging findings. Multivariate logistic regression analysis was conducted to develop the risk prediction nomogram of UTIs for NGB patients. C index was used for the internal and external validation of that model.Results: The occurrence of UTIs was 45.7% (154 of 337), 52.6% (102 of 194), and 36.4% (52 of 143) in the overall, training and validation data sets, respectively. The prediction nomogram was developed with 5 prognostic factors which included white blood cell (WBC) in blood, Leukocyte (LEU) in urine, Urinary pH, length of stay and urination mode. The nomogram presented good discrimination with a C-index value of 0.921 (95% confidence interval: 0.87396???0.96804) and good calibration. The C-index values of the interval validation and external validation were 0.8905541 and 0.817, respectively. The results of decision curve analysis (DCA) demonstrated that the model was clinically useful.Conclusions: The prediction nomogram we developed is a simple and accurate tool for early prediction of UTIs in patients with NGB. This tool can assess risk of UTIs early, allowing for timely initiation of appropriate preventive measures. 相似文献
1000.
Tolerogenic dendritic cells (tDCs) potently induce and maintain tolerance based on their distinct characteristics compared with conventional DCs. Recent reports show that donor or host tDCs promote allograft survival in mice. In this study, the efficacy of third‐party tDCs in the prevention of acute graft‐versus‐host disease (aGVHD) was evaluated. In vitro, tDCs derived from the bone marrow (BM) of D1 mice were induced by GM‐CSF, IL‐10 and TGF‐β1. The phenotypes, expression of cytokines and suppression of tDCs were analysed. In vivo, the effects of adoptive transfer of third‐party‐tDCs were evaluated in an MHC‐mismatched aGVHD mouse model. Survival, body weight, GVHD scoring, histopathological specimens and serum cytokines were analysed in tDC‐treated mice and untreated controls. Tolerogenic DCs had low expression of MHC and co‐stimulatory molecules, expressed high levels of ‘immunosuppressive’ cytokines and suppressed allo‐CD4+T cell proliferation. In the B6→D2 mouse model, all aGVHD mice died within 18 days. Fortunately, third‐party tDCs transferred at low doses (104) effectively prolonged survival after allo‐BMT. Furthermore, in the mice treated with 104 tDCs, serum levels of IL‐10/TGF‐β were significantly higher and the percentage of Foxp3+ cells continually increased compared with the mice treated with other doses of tDCs. Third‐party tDCs play a crucial role in reducing the severity of aGVHD by modulating the secretion of various cytokines and expanding Foxp3+ regulatory T cells, which suggests the possibility of using third‐party tDCs for therapeutic applications. Furthermore, special attention should be paid to the optimal range of tDCs for preventing allograft rejection. 相似文献