The early and effective diagnosis is crucial to efficacious treatment of pulmonary tuberculosis, especially for smear negative cases and MDR-TB, and is one of the priorities of global tuberculosis control and prevention. The traditional methods which have been used for decades of years, show many well-known drawbacks, in terms of fast speed and time consuming. Recently, some new promising diagnostic methods emerged, which have been expected to optimize the diagnosis of tuberculosis, especially for MDR-TB.

Objective To investigate the incidence of drug resistance among new and retreatment TB patients from special hospital.Methods Totally 500 smear positive TB patients from June 2013 to December 2014 in Beijing Chest Hospital were enrolled.Phenotypic susceptibilities to cultured isolates were analyzed in 15 anti tuberculosis drugs by MGIT 960,include Isoniazid (INH),Rifampicin (RFP),Streptomycin (STR),Ethambuto (EMB),Kanamycin (Km),Amikacin (Am),Capreomycin (Cm),Ofloxacin (Ofx),Levofloxacin (Lfx),Moxifloxacin (Mfx),Paza-aminosalicylate (PAS),Protionamide (Pto),Linezolid (Lzd),Ethionamide (Eto),Pyrazinamide (PZA).Results A total of 500 TB cases were enrolled.71 samples among these were NTM infection and 12 samples were contaminted.The rest of 417 of cases infected with Mycobacteriuma,and the rate of drug resistance was 47.2％ (192/417) and the MDR rate was 28.2％ (120/417).The retreatment was significantly higher than that of the new in any drug resistance rate and MDR rate (P =0.000).100 of the retreatment isolates and 50 of the new isolates with Mycobacteriuma were selected to do the drug susceptibility test in 11 subsequent anti tuberculosis drugs (include:PZA,Am,Km,Cm,Ofx,Lfx,Mfx,PAS,Pto,Lzd,Eto).Five cases were contaminated,and in the rest of the cases,48 was the new and 97was the retreatment.The rate of the drug resistance to PZA,Am,Km,Cm,Ofx,Lfx,Mfx for the retreatment were significantly higher than the new (P ＜ 0.05).The rate of drug resistance to PAS,Pto,Lzd and Eto for the new and reteartment were no markedly differential in statistics.Conclusion This study further confirmed the rate of drug resistance in retreatment cases is higher,and the management of tuberculosis patients should be further strengthened.

Objective To explore the pathological features and the causative particles of severe acute respiratory syndrome (SARS) for providing evidences of SARS prevention and clinical treatment. Methods A dead case of SARS of China was studied by light microscopy, electron microscopy, histochemical and immunohistochemical stain. Results The major pathological changes of lung in the SARS case were acute pulmonary interstitial exudative and leakage inflammation, with predominant lymphocyte infiltration. The hyaloid membranes were formed in 20%～30% pulmonary alveoli. The diffuse pulmonary epithelial injury was observed, and virus like inclusions were found in about 30% of total alveolar epithelia by histochemical stain, but chlamydia like inclusions were found occasionally. Meanwhile, the extra pulmonary organs, such as lymph nodes and spleen, showed extensive haemorrhagic necrosis inflammation, accompanied macrophage/histocyte reactive proliferation with erythrocytophage. The double adrenal glands also presented focal haemorrhagic necrosis inflammation. Under the electron microscopy observation, virus like particles with 100 ～150 nm diameter and halo or garland envelopes were found in more than 30 % alveolar epithelial cells, endothelial cells in lung tissues, and also in a part of cardiomyocytes, lymphocytes and macrophages in lymph nodes. The virus like particles were mainly located in cytoplasm and dilated reticular endoplasm. In contrast, chlamydia like particles were commonly visualized in multiple extra lung organs such as liver, but very few in the lung. Immunohistochemistry showed the positive reactions in the lung tissues with the serum IgG and/or IgM from the dead case himself and other SARS convalescent stage cases from Guangdong province of China. Conclusion In the severe SARS case, predominant acute interstitial exudative and leakage inflammation, often with the formation of hyaloid membranes in pulmonaryalveoli, and the haemorrhagic necrosis inflammation of immune organs might be pathological features of SARS. According to the structures, diameter and location of the virus like particles found in this case, combined with the pathological changes, we should consider that those virus like particles might be a new kind of coronavirus, and this kind of virus might be the main causative agent of SARS. However, the chlamydia like particles frequently observed in extra lung organs also suggested the potential new kind of coronavirus might be coexist and synergicallly cause SARS. Our findings in this study provide several evidences for SARS clinical therapy such as application of corticosteroid and enhancement of immune ability and combination of anti virus and anti chlamydium drugs.

Objective To study the pathological changes in organs remote from the lung in SARS patient. Methods The pathological changes in extra lung organs and potential coronavirus infection were studied by using light and electron microscopic examinations as well as special virus inclusion stains in the tissues obtained from an autopsy of a patient who died of SARS. Results Besides the lesions in the lung, pathological changes were found also in the central nervous system (CNS), including the cerebrum, cerebellum, thalamus, pons, and medulla oblongata, such as widening of the Virchow Robin′s space, infiltration of a few lymphocytes and macrophages in the parenchyma, vasodilatation and congestion. However, no significant neuron degeneration or necrosis was identified. Vasodilatation in the lamina propria of mucosa and submucosa of the digestive tract with some lymphocytes infiltration, and epithelial nuclear vacuolation, and occasional apoptosis were observed in the mucosal epithelial and glandular cells, as well as focal hemorrhage in segments of the small intestine. Mesenchymal edema and infiltration of a few lymphocytes in the pancreas were noted. Very mild lymphocyte infiltration, but no viral inclusions, was found in the convoluted seminiferous tubules of the testis. The patient who died of SARS was proved to have arteriosclerosis of the coronary arteries, and coronavirul particles were identified in the blood vessels under electron microscopic examination, however no coronavirul particles were found in the brain or the testis of the patient. Conclusion There were mild hypoxic changes in the tissue of CNS in the patient with severe SARS without invasion of the virus. It was confirmed that there were coronavirul particles in the blood of the patient at the acute stage of SARS. Since the patient who succumbed to the disease had a history of coronary arteriosclerosis, it was inferred that cardiovascular disease might be a contributory factor of mortality in this patient with severe SARS.

Objective To explore the target cells of SARS coronavirus infection in vivo and to provide the evidence of multi organ injuries produced by SARS coronavirus infection. Methods Three biotin labeling oligonucleotide probes were synthesized according to the published gene sequence of SARS coronavirus. The location, distributtion and quantity of SARS coronavirus in 2 autopsy cases of SARS were studied by in situ hybridization and electron microscopic examination. Results SARS coronavirus particles were identified in multiple organs. In lungs, SARS coronaviruses were located predominantly in the cytoplasm of bronchiolar and alveolar epithelial cells, in a part of macrophages and endothelial cells as well as a few infiltrated lymphocytes. In situ hybridization showed that in target cells SARS coronavirus distribution presented a cytoplasmic or inclusive pattern, and the mean number of positive cells in the pulmonary tissue was 80?25 per 200? field. Electron microscopic examination showed that the coronaviral particles were 100～150 nm in diameter, with low density electron cores with halo or garland envelopes. About 15% of renal tubular epithelial cells harbored SARS coronavirus, and a few parenchymal cells and sinusoid capillary endothelial cells of adrenal glands were hybridization positive. In the gastro intestinal tract, SARS coronaviruses were seen in the cytoplasm of mucosal and crypt epithelial cells, mostly in 2/3 of superficial mocosa. Under both electron microscopy and in situ hybridization observation, SARS coronaviruses were found focally distributed in some cardiomyocytes. The SARS coronavirus positive particles were also noted in macrophages/histocytes, sinusoid endothelial cells, as well as a few lymphocytes in thoracic and celiac lymph nodes. In addition, coronavirus particles were also seen in a few testicular epithelial cells and Leydig's cells. Conclusion SARS coronavirus could attack multiple target cells, implicating that SARS might cause multi organ damages, with lungs as the predominant organ of injury.

BACKGROUND:At present, the development of reprogramming technology provides a wide prospect for stem cellresearch. Through the ectopic co-expression of reprogramming factors, the somatic cells can be reprogrammed to a pluripotent state, termed as induced pluripotent stem cells, which can avoid the ethical controversy faced in the research and application of embryonic stem cells. Also, we can generate patient-specific and disease-specific induced pluripotent stem cells, which significantly decrease immuno-rejection. However, reprogramming technology faces some chal enges, such as low efficiency and safety.
OBJECTIVE:Based on the characteristics of induced pluripotent stem cells and the principles of reprogramming, to detail the progress in reprogramming technology from five aspects, including cellresources, carriers, transcription factors, microRNA and signal transduction pathway. 
METHODS:A computer-based online retrieval was performed to search papers published form January 1990 to April 2013 in VIP periodical ful-text database, Wanfang periodical ful-text database, CNKI periodical ful-text database, PubMed database and Springer database with key words of“reprogramming, induced pluripotent stem cell, signal transduction pathway, epigenetics, microRNA, transcription factor, vector, somatic cell, smal molecule compound, safety”both in Chinese and English. After excluding objective-independent papers, 67 papers were included for further analysis.
RESULTS AND CONCLUSION:By exploring different cellresources, different carriers, various combination of transcription factors, microRNAs or inhibition of the signal transduction pathways, the reprogramming efficiency and safety have been improved greatly. However, currently, induced pluripotent stem cells stil could not meet the requirement of clinical application. To achieve the clinical application of induced pluripotent stem cells, it is urgent to explore the mechanism of reprogramming, and to optimize the programming strategy.

Objective:To investigate the protective role of heme oxygenase-1 and its reaction product,carbon monoxide against acute liver injury induced by carbon tetrachloride in rats.Methods: Thirty male Sprague-Dawley rats were randomly divided into six groups with five in each.The control group received a single dose of corn oil injection.Carbon tetrachloride was injected intraperitoneally(i.p) to establish acute liver injury models in rats.Hemin(50 ?mol/kg) was administered i.p.12 hours before CCl_4 treatment,with an aim to induce HO-1 protein expression in the liver of rats.Carbon monoxide was injected i.p.12 hours prior to CCl_4 injection,resulting in about 8%-12% carboxyhemoglobin concentration in vivo.The expression of HO-1 in the liver of hemin-treated rats was determined by western blot method at different time points.At 24 h after carbon tetrachloride administration,all rats were sacrificed to collect blood samples for the examination of ALT,AST levels and to remove liver tissues for analysis of MDA concentration,SOD activity and caspase-3 activity as well as TNF-a contents.In addition,histopathological changes were investigated and hepatocyte apoptosis was detected by TUNEL method.Results: The administration of carbon tetrachloride to rats caused a marked hepatic damage,characterized by significant elevation of serum ALT,AST levels(2 136.3?163.4 U,1 422.7?221.7 U) and liver MDA con-tent(5.28?0.93 ?mol/g),caspase-3 activitiy(optical density value(4.69)?1.02) and TNF-? level(256.3?27.3 ng/L) combined with a remarkable reduction in liver SOD activity(45.9?14.8 U/mg) as compared with the control rats.Histopathological observations revealed severe damage in the liver and prominent hepatocyte apoptosis took place in CCl_4treated rats.However,pretreatment with hemin could induce high expression of HO-1 protein and exert potent protective effects against liver injury,as demonstrated by a significant decrease in ALT,AST levels(287.1?24.3 U,246.2?21.7 U) and MDA concentration(3.27?1.34 ?mol/g),reduction in caspase-3 activity(optical density value 2.49?1.47) and TNF-? level(132.6?19.5 ng/L),as compared with the CCl_4-treated rats.Moreover,hepatocyte apoptosis and liver injury were both attenuated remarkably in the liver of rats pretreated with hemin.In contrast to hemin administration,single injection of exogenous CO produced the same protective effects,as indicated by the remarkable reduction of ALT,AST levels and caspase-3 activity and TNF-a levels.Conclusion: The above results suggest that HO-1/CO system has a potent protective effect on acute liver injury induced by carbon tetrachloride in rats.Induction of HO-1 expression and low concentration of CO can inhibit the progress of hepatic damage,which might be due to the alleviation of lipid peroxidation and reduction of caspase-3 activity or inhibition of TNF-? level.

Teaching the foreign students clinical medicine in English in the earlier period of foreign students education has played a vital role but also has such problems as teachers,difficulties in the later teaching and so on.Through practice we find that it is necessary to transit the mode from teaching in English to bilingual education,and finally teaching in Chinese in the internship to conform with the present medical foreign students education situation.Therefore ability of teaching in English and proficiency in Chinese are needed to improved as soon as possible.

OBJECTIVE To investigate the change of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),intercellular adhesion molecules(ICAM-1),matrix metalloproteinases 2 (MMP-2) and MMP-9 contents in cultured pulmonary microvascular endothelial cells (PMVECs) in rats after perfluoroisobutylene (PFIB) exposure. METHODS PMVECs were separated and purified using a modified method of implantation of pulmonary tissues. After identification,PMVECs were divided into the normal control group and the PFIB-exposed groups(n=3). The PFIB-exposed groups inhaled PFIB at the concentration of 200 mg · m-3 for 5 min in a flow-past header,while the normal control group were PMVECs in quiescent condition. The supernatants and lysates of PMVECs were harvested at 0.5,1,2,4 and 8 h,respec?tively, after execution. The contents of TNF-α,IL-1β,ICAM-1,MMP-2 and MMP-9 were measured by ELISA,and the activity of MMP-2 and MMP-9 was measured by gelatin zymography. RESULTS① According to the morphologic characteristics of cell growth and the expression of specificity antigens and the bind experiment of phytohemagglutinin,the cells separated and purified by modified method shared the characteristics of PMVECs.②TNF-αwas rapidly expressed by PMVECs at 0.5 h post PFIB stimulation and the maximum value was achieved at 2 h post PFIB stimulation(P<0.05). The newly synthesized TNF-α was slowly released out of the cells. The maximum TNF-α in the supernatant was achieved at 4 h post stimulation.③Within 2 h of stimulation,PMVECs synthesized a large amount of IL-1β and peaks at 2 h. However,IL-1βwas never released to the extracellular milieu.④The amount of ICAM-1 was rapidly synthesized by PMVECs after PFIB stimulation,but at a low level.⑤After stimulation with PFIB,MMP-2 in the supernatant of PMVECs culture was gradually increased,peaked at 2 h and then decreased subsequently. The biological activity of MMP-2 in the supernatant was also enhanced after PFIB stimulation. PFIB did not stimulate synthesis or secretion of MMP-9,indicating that PMVECs were not the main source of MMP-9 during PFIB inhalation-induced acute lung injury. CONCLUSION PFIB stimulates the surviving PMVECs to synthesize a large amount of TNF-α,IL-1β, MMP-2 and conjunctive ICAM-1.

We investigate the different expression of toxin gene mazF3,6,9 and antitoxin gene mazE3,6,9 in the drug-resistance Mycobacterium tuberculosis,we used quantitative real-time polymerase chin reaction method to detect the expression level of toxin gene mazF3,6,9 and antitoxin gene mazE3,6,9 in M.tuberculosis (20 mono-resistance strains,20 multidrug resistance strains and standard strain H37Rv).The differences of gene expression levels between groups were analyzed by oneway ANOVA.Contrasting with control group,toxin genes mazF6,9 were up-regulated expression levels both in mono-resistance (11.1519±22.31721;8.4306±17.97897) and multidrug resistance (4.6016±1.29018;6.9627±6.92948),had statistical significance (P＜0.01),mazF3 expression levels had statistical significance neither in mono-resistance nor in multidrug resistance (P＞0.05);antitoxin genes mazE3 was in down-expression level,and had statistical significance both in mono-resistance (0.3606±0.12527) and multidrug resistance (0.2016±0.16542) (P＜0.01),mazE6 had no statistical significance (P＞0.05)either in mono-resistance or multi drug resistance,mazE9 only in multidrug resistance(0.3989±0.37679) was in downexpression level,and has statistical significance (P＜0.001).The toxin gene mazF6,9 and antitoxin gene mazE3,9 may participate in the drug-resistance formation of M.tuberculosis.