Association of TLR1 gene polymorphisms with pulmonary candida infection and candida colonization in Guizhou Han patients with chronic obstructive pulmonary disease / 医学研究生学报

Objective Studies are rarely reported on the correlation of the Toll-like receptor (TLR) gene polymorphisms with fungal infection in the Chinese Han population. This study aims to explore the association between TLR gene polymorphisms and pulmonary candida infection (PCI) and candida colonization (CC) in patients with chronic obstructive pulmonary disease (COPD) in the Guizhou Han population. Methods Using the polymerase chain reaction-direct sequencing (PCR-SBT) method, we genotyped six single nucleotide polymorphisms (SNP) of the TLR1, TLR2 and TLR4 genes in 344 Guizhou Han patients with COPD, including 80 cases complicated by PCI (the PCI group), 103 cases complicated by CC (the CC group), and 161 negative controls. We analyzed the correlation of the SNPs with PCI and CC in the COPD patients in different genetic models with the SNPstats online software, measured the levels of IL-6, IL-8, IL-1β and TNF-α proteins in the plasma of the patients by ELISA, and assessed the functional consequences of these polymorphisms. Results The polymorphisms of rs5743611, rs5743708, rs4986790 and rs4986791 were found in none of the patients. The genotype frequency of rs4833095 was significantly different between the PCI and control groups in the codominant, dominant and overdominant models (P < 0.05), with the dominant model as the best genetic pattern. No statistically significant difference was observed either in the rs4833095 genotype frequency between the CC and control groups (P > 0.05) or in the rs5743618 genotype frequency between any two groups (P > 0.05). In the PCI group, the T allele of the rs4833095 polymorphism significantly decreased the levels of IL-6, IL-8 and IL-1β in the plasma (P < 0.05), and that of TNF-α as well, though with no statistically significant difference (P > 0.05). Conclusion The rs4833095 polymorphism of the TLR1 gene is associated with PCI in COPD patients. The T allele of rs4833095 may affect the function of TLR1, decrease the levels of IL-6, IL-8 and IL-1β proteins in the plasma. Neither rs4833095 nor rs5743618 gene polymorphism is correlated with the susceptibility to candida colonization.

Analysis on microstructure and biomechanical properties in different regions of osteoporotic femoral head / 医用生物力学

Objective To investigate the structure and biomechanical property differences in different regions of the femoral head for elderly patients with femoral neck fractures, and to study its influence on internal fixation for fracture. Methods Twenty femoral head specimens were collected from elderly patients with femoral neck fracture after joint replacement. The femoral head was divided into 3 parts (lateral, inferior and medial region) with reference to anatomical markers on surface of the femoral head. After the position and drilling direction of the ring drill were determined, a circular drill was used to obtain the cylindrical cancellous bone columns with 10 mm in diameter and 10 mm in height. The data of cancellous bone columns in different regions were analyzed by Micro-CT scanning system, including bone volume fraction (BVF), trabecular space (Tb.Sp), trabecular thickness (Tb.Th), the number of trabecular number (Tb.N), the bone surface volume ratio (bone surface/bone volume, BS/BV), structural model index (SMI). Mechanical property differences of bone tissues in different regions were calculated by micro-finite element analysis. ResultsBone mass in the elderly osteoporotic femoral head decreased, and there were significant differences in bone microstructure and mechanical properties in different regions of the femoral head. Bone microstructure and mechanical properties in medial region were obviously superior to those in lateral and interior region. Conclusions The bone structure and mechanical strength in medial region of the femoral head are obvious superior to those in lateral and inferior regions. The position for internal fixation should be fully considered during treatment of osteoporotic femoral neck fracture in clinic.

Infliximab protects against pulmonary emphysema in smoking rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>It is widely accepted that tumor necrosis factor-α (TNF-α) plays an important role in the pathogenesis of emphysema. This study aimed at investigating the protective effects of anti-TNF-α antibody, infliximab, in the development of emphysema induced by passive smoking in rats.</p><p><b>METHODS</b>Thirty-nine rats were randomly divided into a normal control group (group 1), an emphysema group (group 2), and an infliximab-intervention group (group 3). Rat models of emphysema were established by exposure to cigarette smoking daily for 74 days. After 1 month, the infliximab intervention group was treated with infliximab via subcutaneous injection. The levels of TNF-α, IL-8 and vascular endothelial growth factor (VEGF) in bronchoalveolar lavage fluid (BALF) were measured with enzyme linked immunosorbent assay (ELISA). The number and classification of cells in the BALF were measured. Lung tissue sections stained by hematoxylin and eosin (HE) were observed, and mean linear intercept (MLI) and mean alveolar numbers (MAN) were measured. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) methods were used to examine the percentage of positive cells and distribution of apoptotic cells.</p><p><b>RESULTS</b>The levels of TNF-α and IL-8 in BALF were higher in group 2 than in group 1 and group 3. The MLI was greater in group 2 than that in group 1 and group 3 while MAN was decreased. The concentration of VEGF in BALF of group 2 was significantly decreased as compared with group 1. The total cells and neutrophils number was significantly increased in group 2 as compared with group 1 and group 3, so was the percentage of neutrophils. The number of TUNEL positive cells in the alveolar septa was significantly increased in group 2 as compared with group 1 and group 3.</p><p><b>CONCLUSION</b>Infliximab protects against cigarette smoking-induced emphysema by reducing airway inflammation, attenuating alveolar septa cell apoptosis and improving pathological changes.</p>

Exploration in the Reform of Medical Microbiology Teaching on Eight-year MD Program / 微生物学通报

In the reform of medical microbiology education on medical students of 8-year-education pro-gram, we compared the traditional teaching methods with Problem Based Learning (PBL) method. Through our practice, we have found that the combination of traditional lecture-based learning and PBL seems to better match the students’ way of learning. The lack of basic knowledge of the students hindered their learn-ing effect during the bilateral discussion in the PBL education. We also found that the application of PBL in medical microbiology education is an iterative process and should be promoted step by step. The theoretical level and the innovative ideas of the teachers play a crucial role in the dynamic process of education reform.

Discussion on Students' Common Problems During Medical Microbiology Experiment Practice / 微生物学通报

As a major ingredient of high medical college education,experiment practice plays an important role for medical students in integrating the medical theory with practice,training their capability of analyzing and thinking to definitively solute the problems in their study.Microbiology experiment is characterized with strong comprehensiveness and manipulation,which requests the students both aseptic operation and consciousness of bio-safety.To promote the student's comprehensive diathesis and to improve the experiment teaching quality,several common problems of students in medical microbiology experiment practice were analyzed and discussed in this article.