Different types of acids from fermentation environment or industrial microorganisms exist during fermentation process. Acids may inhibit growth and metabolism of industrial strains, namely acid stress. The tolerance mechanisms of acid stress include regulation of intracellular proton concentration, protection and restoration of intracellular macromolecules, changes in cell membrane composition and acid stress response at whole cell level. Screening and modification methods have been applied to improve acid-stress tolerance of industrial strains for decades. In this review, we provide insights into acid-stress tolerance of industrial microorganisms and address the modification of microbial pathways to improve acid-stress tolerance.
Acids ; chemistry ; Fermentation ; Hydrogen-Ion Concentration ; Industrial Microbiology ; Metabolic Engineering

BACKGROUNDHemodynamic evaluation is crucial for the management of patients with pulmonary hypertention. Clinicians often prefer a rapid and non-invasive method. This study aimed to examine the feasibility of transthoracic echocardiography for the measurements of hemodynamic parameters in patients with pulmonary hypertension.

METHODSA prospective single-center study was conducted among 42 patients with pulmonary hypertension caused by different diseases. Transthoracic echocardiography and right-heart catheterization were performed within 24 hours. Pulmonary artery systolic, diastolic and mean pressure (PASP, PADP and PAMP), cardiac output (CO), and pulmonary capillary wedge pressure (PCWP) were measured by both methods. A linear correlation and a Bland-Altman analysis were performed to compare the two groups of hemodynamic parameters.

RESULTSA good correlation was found between invasive and non-invasive measurements for PASP (r = 0.96), PADP (r = 0.85), PAMP (r = 0.88), CO (r = 0.82), and PCWP (r = 0.81). Further agreement analysis done by the Bland-Altman method showed that bias and a 95% confidence interval for PASP, PADP, and CO were clinically acceptable while great discrepancies existed for PAMP and PCWP.

CONCLUSIONSThe non-invasive measurements by PASP, PADP, and CO in patients with pulmonary hypertension correlate well with the invasive determinations. Transthoracic echocardiography (TTE) was inappropriate for estimating PCWP and PAMP.

Adolescent ; Adult ; Cardiac Catheterization ; Cardiac Output ; Echocardiography ; Female ; Hemodynamics ; Humans ; Hypertension, Pulmonary ; physiopathology ; Male ; Middle Aged ; Prospective Studies ; Pulmonary Wedge Pressure

OBJECTIVETo investigate the modification of GSTM1, GSTT1 and GSTP1 gene polymorphisms on urinary 1-hydroxypyrene (1-OHP) excretions in workers under different exposure levels.

METHODSFour hundred and forty-seven occupationally exposed workers from two coking plants and 220 control workers from a wire rod plant were genotyped to analyze the modification of GSTM1, GSTT1 and GSTP1 gene polymorphisms on urinary 1-OHP excretions.

RESULTSThe urinary 1-OHP concentration in exposed group was much higher than that in control group (4.61 vs 0.34 µmol/mol Cr, P < 0.05). Occupational exposure levels and cigarette smoking were of the dominating factors affecting 1-OHP excretions in urine. After controlling potential confounders, decreased excretion of urinary 1-OHP was associated with GSTP1 I105V AG + GG genotype in coke oven workers (single-gene model, P = 0.012; multi-gene model, P = 0.011) and with GSTT1 null type in the analysis including all subjects (P = 0.055 in both single-gene and multi-gene models). GSTT1 and GSTP1 were interacted on the urinary concentrations of 1-OHP.

CONCLUSIONUrinary 1-OHP concentrations can be modified by GSTM1, GSTT1 and GSTP1 gene polymorphisms, indicating that these genes are involved in the metabolism of polycyclic aromatic hydrocarbons.

Adolescent ; Adult ; Control Groups ; Genotype ; Glutathione S-Transferase pi ; genetics ; Glutathione Transferase ; genetics ; Humans ; Male ; Middle Aged ; Occupational Exposure ; Polymorphism, Single Nucleotide ; Pyrenes ; analysis ; Urinalysis ; Young Adult

OBJECTIVETo investigate the associations between periodontal diseases, presence of Porphyromonas gingivalis (P. gingivalis), serum levels of pro-inflammatory mediators and preterm low birth weight (PLBW).

METHODS60 women (30 PLBW and 30 healthy women), were recruited after postpartum within 3 days in this case-control study. Periodontal measurements including plaque index (PI), bleeding index (BI), probing pocket depth (PD) and clinical attachment loss (CAL) were assessed. The subgingival plaque was collected before periodontal examination and analysed by polymerase chain reaction (PCR) for the presence of the 16S rRNA gene specific to P. gingivalis, while the venous and umbilical cord blood specimens collected were determined by enzyme-linked immunosorbent assay (ELISA).

RESULTSThe PLBW cases had a poorer oral conditions and the presence of P. gingivalis was found in a higher proportion in the PLBW than the healthy pregnant (56.7% vs. 30.0%, P < 0.05). Both of the presence of periodontitis and P. gingivalis have been found to be associated weakly with a shorter gestational age and a lower birth weight (P < 0.05). The levels of IL-1beta, IL-6 and prostaglandin-E2 (PGE2) in both of the blood samples showed higer levels between the PLBW and normal groups (P < 0.01). The IL-1beta and PGE2 levels in maternal serum were higher with a severe periodontal disease in the PLBW group (P < 0.01).

CONCLUSIONThere may be a possible link between periodontal diseases and PLBW.

Adult ; Case-Control Studies ; Dental Plaque ; Dental Plaque Index ; Female ; Humans ; Infant, Low Birth Weight ; Infant, Newborn ; Interleukin-6 ; Periodontal Diseases ; Periodontitis ; Porphyromonas gingivalis ; Pregnancy ; Premature Birth ; RNA, Ribosomal, 16S

BACKGROUNDAn implantable cardioverter-defibrillator (ICD) has been suggested for heart failure patients for primary prevention of sudden cardiac death. However, few data have been reported on the application of ICD as primary prevention of sudden cardiac death in China. We evaluated the value of primary prevention ICD therapy in Chinese patients with heart failure.

METHODSThirty-four patients at an average age of (60.2 +/- 13.7) years seen in Peking Union Medical College Hospital were treated with ICD implantation for primary prevention of sudden cardiac death from November 2005 to July 2009. Single-chamber ICDs were implanted in 16 (47.0%) cases, and dual-chamber or cardiac resynchronization therapy defibrillators in 18 (53.0%) cases. The patients had an average left ventricular ejection fraction of (26.9 +/- 5.5)% (11% to 35%), of which 18 (53.0%) patients had ischemic cardiomyopathy and 16 (47.0%) patients had non-ischemic cardiomyopathy. All patients were followed up at three months after the implantation and every six months thereafter or when prompted by an ICD event.

RESULTSThere were five (14.7%) deaths, including two of heart failure and three with a non-cardiac course, during an average follow-up of (15.0 +/- 11.9) months. Forty-one ICD therapy events were recorded, including 19 (46.3%) appropriate ICD therapies in six patients and 22 (53.7%) inappropriate ICD therapies in four patients with single chamber leads. Inappropriate ICD therapies were mainly due to supraventricular tachyarrhythmias, especially atrial fibrillation. Patients with ischemic cardiomyopathy and non-ischemic cardiomyopathy did not differ in the incidence of either appropriate or inappropriate therapy.

CONCLUSIONSICD for primary prevention of sudden cardiac death in China prevents patients from arrhythmia death. Relatively high incidence of inappropriate therapies highlights the importance of an atrial lead.

Aged ; Death, Sudden, Cardiac ; prevention & control ; Defibrillators, Implantable ; adverse effects ; Female ; Heart Failure ; mortality ; therapy ; Humans ; Male ; Middle Aged ; Treatment Outcome

OBJECTIVETo study the characteristics of occupational exposure of polycyclic aromatic hydrocarbons (PAHs) in coke oven workers.

METHODSSamples were collected individually and PAHs concentration in the ambient air were assayed by high performance liquid chromatography (HPLC) and toxic equivalency factors (TEFs) were introduced to assess the carcinogenic potency.

RESULTSThe levels of PAHs occupational exposure in oven workers at topside was higher than at side oven and bottom oven (P < 0.05). Non-carcinogenic PAHs were more than 70% of total PAHs and benzo[a]pyrene accounted for 65.5% approximately 72.4% of total benzo[a]pyrene equivalents. Total occupational exposure level of PAHs in coke oven workers was positively related to the content of benzo[a]pyrene and pyrene, respectively (r(2) = 0.84, r(2) = 0.94, P < 0.05).

CONCLUSIONCoke oven workers were exposed to a high level of PAHs which possessed some extent of carcinogenic potency, and benzo[a]pyrene is the chief carcinogenic substance.

Benzo(a)pyrene ; analysis ; toxicity ; Carcinogens ; analysis ; toxicity ; Chromatography, High Pressure Liquid ; Coke ; Humans ; Occupational Exposure ; Polycyclic Compounds ; analysis ; toxicity

Objective To observe the clinical features and cardiac magnetic resonance imaging (CMR) characteristics of patients with endomyocardial biopsy (EMB)-proven cardiac amyloidosis (CA).Methods EMB proven CA patients underwent CMR examination from September 2006 to December 2010 were included.The findings of clinical manifestation,electrocardiogram,echocardiography and CMR were analyzed.Results Among the 18 patients with EMB verified CA,5 patients underwent CMR.All 5 patients had heart failure symptoms and electrocardiogram was abnormal.Echocardiogram showed concentric left ventricular hypertrophy,granular appearance of the myocardium,left atrial enlargement and moderate to severe left ventricular diastolic dysfunction.CMR revealed increased thickness of the left ventricular wall (especially at the inter-ventricular septum),enlarged bilateral auricle,restricted left ventricular filling with normal or mild to moderate reduced systolic function.Pleural and pericardial effusions were observed in 2 patients.Abnormal late gadolinium enhancement (LGE) was detected in all 5 patients.CMR revealed different patterns of LGE.Left ventricular global subendocardial delayed gadolinium enhancement or transmural delayed gadolinium enhancement were found,and patients also showed line-,granular- or patchylike enhancement.The degree and range of LGE paralleled the disease course and were consistent with electrocardiogram changes.Conclusions As a noninvasive diagnostic tool,CMR is valuable in the diagnosis of CA.For patients with clinical suspicion of CA,CMR could be a helpful diagnostic tool,especially in the hospitals where EMB is not available.

Objective To investigate the clinical characteristics, electrocardiography, electrophysiological features and the eff ectiveness of catheter ablation of ventricular arrhythmias originating from left ventricle posterior papillary muscles. Methods Clinical features and electrocardiography of 16 patients with ventricular arrhythmias arising from left ventricular posterior papillary muscles underwent catheter ablation were retrospectively analyzed. Activation mapping and/or pace mapping were performed to identify the site of origin and transthoracic echocardiography were used to demonstrate ablation catheter position and contact. The immediate success and recurrence rates were evaluated. Results During arrhythmias, QRS wave duration of 16 patients [5 men, mean age (45.0±18.2) years] was (155.1±9.0)ms. The prevalence of R>r' and r

OBJECTIVE:To systematically evaluate therapeutic efficacy and safety of pitavastatin comparison of atorvastatin in the treatment of primary hypedipemia in Chinese adults,and to provide evidence-based reference for clinic.METHODS:Retrieved from The Cochrane Library,PubMed,Chinese Journal Full-text Database,Wanfang database,and manually search Google Scholar,Baidu academic search engine,randomized controlled trials (RCTs) about pitavastatin (trial group) vs.atorvastatin (control group) in the treatment of primary hyperlipemia in Chinese adults were collected.After literature screening,data extraction,quality evaluation of included studies with modified Jadad scale,Meta-analysis of the levels of total cholesterol (TC),low density lipoprotein cholesterol (LDL-C),triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C),response rate and the incidence of ADR was conducted by using Rev Man 5.3 statistical software.RESULTS:A total of 5 RCTs were included,involving 456 patients.Results of Meta-analysis showed that the decrease of TC level [MD=0.09,95％CI(0.01,0.16),P=0.03] in trial group was more better than control group,while the increase of HDL-C level [MD=0.08,95％ CI (0.01,0.14),P=0.03] and the decrease of the TG level [MD=-0.13,95％ CI (-0.20,-0.06),P=0.000 4] in trial group were worse than control group,with statistical significance.There was no statistical difference in the decrease of LDL-C[MD=-0.01,95％ CI (-0.13,0.10),P=0.84],response rate [OR=0.75,95％CI (0.15,3.66),P=0.72] or the incidence of ADR [OR=0.68,95 ％ CI (0.44,1.05),P=0.08] between 2 groups.CONCLUSIONS:Pitavastatin has better therapeutic efficacy in decreasing TC,but its therapeutic efficacy in decreasing LDL-C is similar to that of atorvastatin;its therapeutic efficacy in decreasing TG and increasing HDL-C is worse than that of atorvastatin.The safety of them is equivalent.

Diabetes has become the third largest killer to human life and health,and its development is closely related to the intestinal flora imbalance caused by series of consequences.So adjusting the structure of intestinal flora becomes a new idea for the treatment of diabetes.Traditional Chinese medicine (TCM) has good curative effect in prevention and treatment of diabetes,and improvement on the structure of intestinal flora may be one of its important mechanisms.The article reviewed the research progress on prevention and treatment of diabetes by TCM single components (berberine,phloridzin,rheinic acid,etc),TCM single prescription (essential oil from Cinnamomum cassia,flower stalk of Coptis chinensis,total coumarin of Feucedani Radix) and TCM priscriptions (Gegen Qinlian Decoction,Shengjiang Powder,Buzhong Yiqi Decoction,Huanglian Jiedu Decoction,Wenyang Yiqi Huoxue Compound,etc.) based on new targets in intestinal flora,so as to provide reference for the development of TCM for prevention and treatment of diabetes.