The innate immune system plays a crucial role in the rapid recognition and elimination of invading microbes. Detection of microbes relies on germ-line encoded pattern recognition receptors (PRRs) ...that recognize essential bacterial molecules, so-called pathogen-associated molecular patterns (PAMPs). A subset of PRRs, belonging to the nucleotide binding oligomerization domain (NOD)-like receptor (NLR) families, detects viral and bacterial pathogens in the cytosol of host cells and induces the assembly of a multi-protein signaling platform called the inflammasome. The inflammasome serves as an activation platform for the cysteine protease Caspase-1, a central mediator of innate immunity. Caspase-1 initiates a novel form of cell death called pyroptosis. Inflammasome activation by pathogen-associated signatures results in the autocatalytic cleavage of Caspase-1 and ultimately leads to the processing and thus secretion of pro-inflammatory cytokines, most importantly interleukin (IL)-1β and IL-18. Here, we review th
To investigate the etiology and clinical characteristics of hospital-acquired pneumonia (HAP) in China and to provide evidence for appropriate therapy.
We performed a prospective multicenter study in ...13 Chinese urban tertiary hospitals. All HAP cases diagnosed at respiratory general ward and respiratory intensive care unit (RICU) from August 2008 to December 2010 were studied. Epidemiological data, etiology and clinical characteristics of enrolled patients were collected. Sputum or tracheal aspirate and blood cultures, Legionella antibodies and Streptococcus pneumoniae urinary antigen tests were performed. Bacteria to antimicrobial susceptibility test was performed.
A total of 610 cases of HAP were diagnosed during the study, with an overall incidence of 1.4% among 42 877 hospitalized patients, while the incidence was 0.9% (362/41 261) in respiratory general ward and 15.4% (248/1616) in RICU. 93.9% (573 cases) of patients had at least one underlying disease, and 91.0% (555 cases) had exposure to at least one
To investigate the pathogens, clinical manifestations, prognosis of and the risk factors for pulmonary mycosis in China.
All cases of pulmonary mycosis from 16 centers in 10 cities from Jan. 1998 to ...Dec. 2007 that met the diagnostic criteria were included for clinical, microbiological and radiological analysis.
Totally 474 cases of pulmonary mycosis were retrieved. The top 5 pulmonary mycosis was pulmonary aspergillosis (180 cases, 37.9%), pulmonary candidiasis (162 cases, 34.2%), pulmonary cryptococcosis (74 cases, 15.6%), pneumocystis carinii pneumonia (23 cases, 4.8%) and pulmonary mucormycosis (10 cases, 2.1%). The constituent ratio in the last 3 years was similar to that in the former 7 years. The main pathogens of pulmonary candidiasis were Candida albicans (308/474, 65.0%) and Candida tropicalis (57/474, 12.0%), which were sensitive to common azoles. Compared with bacterial pneumonia, pulmonary mycosis showed more symptoms of hemoptysis (147/474, 31.0%) and pleural effusion (95/474, 20.0%), and less ra
The noise of closed loop micro-electromechanical systems (MEMS) capacitive accelerometer is treated as one of the significant performance specifications. Traditional optimization of noise performance ...often focuses on designing large capacitive sensitivity accelerometer and applying closed loop structure to shape total noise, but different noise sources in closed loop and their behaviors at low frequencies are seldom carefully studied, especially their behaviors with different electronic parameters. In this work, a thorough noise analysis is established focusing on the four noise sources transfer functions near 0 Hz with simplified electronic parameters in closed loop, and it is found that the total electronic noise equivalent acceleration varies differently at different frequency points, such that the noise spectrum shape at low frequencies can be altered from 1/
f
noise-like shape to flat spectrum shape. The bias instability changes as a consequence. With appropriate parameters settings, the 670 Hz resonant frequency accelerometer can reach resolution of
at 2 Hz and 6 μg bias instability, and 1300 Hz accelerometer can achieve
at 2 Hz and 31 μg bias instability. Both accelerometers have flat spectrum profile from 2 Hz to 15 Hz.
Leptin is a protein mainly secreted by adipocytes, and the major function of leptin was its role in body weight regulation. It is suggested that increased levels of circulating leptin may contribute ...to anorexia in pathologic conditions including chronic obstructive pulmonary disease (COPD). Recent studies have provided evidence for a link between leptin and proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha). This study aimed to explore the role of serum leptin in the malnutrition of COPD patients, and to observe the changes of serum leptin levels during acute exacerbation, also to investigate relationship between leptin and TNF-alpha.
Seventy-two COPD patients and 34 control subjects participated in this study. Seventy-two COPD patients were divided into 3 groups: group COPD IA (patients without malnutrition during acute exacerbation, n = 25), group COPD IB (patients without malnutrition during stable disease, n = 29), group COPD II (patients with malnutrition during stable disease, n = 18). To eliminate the effect of sex differences, all patients and controls were male. Body mass index (BMI), percent ideal body weight (IBW%), triceps skin-fold thickness (TSF), mid-upper arm circumference (MAC), mid-upper arm muscle circumference (MAMC), serum leptin and TNF-alpha levels, serum prealbumin (PA), serum transferrin (TF), serum albumin (Alb), total lymphocytes count (TLC), forced expiratory volume in one second (FEV(1)), maximal inspiration pressure (MIP) and maximal expiration pressure (MEP) were measured in all participants. Leptin levels were measured by radioimmunoassay. TNF-alpha levels were measured by ELISA. The between group difference and correlation of these parameters were analyzed.
Serum leptin levels were significantly lower in group COPD II (4.07 +/- 3.42) ng/ml than in group COPD IB (9.72 +/- 6.67) ng/ml and controls (8.21 +/- 5.41) ng/ml (P < 0.05). There was no statistically significant difference in serum leptin levels between group COPD IA (10.82 +/- 6.40) ng/ml, group COPD IB (9.72 +/- 6.67) ng/ml and controls (8.21 +/- 5.41) ng/ml. There was no statistically significant difference in serum TNF-alpha levels between group COPD II (8.03 +/- 3.37) pg/ml, group COPD IA (8.90 +/- 1.60) pg/ml, and group COPD IB (7.25 +/- 2.08) pg/ml. There was no significant correlation between leptin and TNF-alpha in any group.
Leptin was not involved in anorexia and weight loss of COPD patients. There was no statistically significant difference in serum leptin levels between COPD patients during stable stage and acute exacerbation, and there was no significant correlation between TNF-alpha and leptin during the regulation of the energy balance in COPD patients.
To investigate the pathogenic causes of community-acquired pneumonia (CAP) in adult patients in China, the relation of previous antibiotic use and the Pneumonia Patient Outcome Research Team (PORT) ...classification to microbial etiology, and the prevalence of drug resistance of common CAP bacteria.
A prospective study was performed on 665 consecutive adult patients with CAP at 12 centers in 7 Chinese cities during one year. The etiology of pneumonia was considered if one of the following criteria was met: (1) valid sputum sample yielding one or more predominant strains; (2) blood cultures yielding a bacterial pathogen; (3) seroconversion, a > or = 4-fold increase or decrease titers of antibodies to Mycoplasma pneumoniae, Chlamydia pneumoniae and Legionella pneumophila. Minimum inhibitory concentration (MIC) of respiratory tract isolates was determined using the agar dilution method.
Pathogens were identified in 324/610 patients (53.1%) with valid serum samples and sputum cultures as follows: Mycoplasma pneumoni
The development of biodegradable and recyclable polymers having the desired material properties required in practical use has provided a partial solution for realizing a sustainable plastics economy. ...Naturally produced commercial poly(3-hydroxybutyrate) (P3HB), one of the much studied biodegradable polyhydroxyalkanoates (PHAs), is a stereoregular thermoplastic material with a high degree of crystallinity, significantly restricting its application due to the stiff and brittle characteristics. Therefore, it is of great significance to overcome the inherent brittleness through decreasing the crystallinity of P3HB. In this contribution, we present a powerful strategy to toughen P3HB via catalytic carbonylative terpolymerization of enantiopure epoxides with different long alkyl side chains and configurations using a binary trimetallic CrIII complex/carbonyl cobalt catalyst system. The structure and stereochemistry of epoxides significantly impact the properties of the resultant PHA copolymers, which spans from viscous oil to tough/ductile and brittle plastics. This study represents a rather rare example of a method to toughen the extensively studied P3HB with epoxide and CO as raw materials.
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