Expression and regulation of HIF-1a in hypoxic pulmonary hypertension: Focus on pathological mechanism and Pharmacological Treatment.

Hypoxia inducible factor-1(HIF-1), a heterodimeric transcription factor, is composed of two subunits (HIF-1α and HIF-1ß). It is considered as an important transcription factor for regulating oxygen changes in hypoxic environment, which can regulate the expression of various hypoxia-related target genes and play a role in acute and chronic hypoxia pulmonary vascular reactions. In this paper, the function and mechanism of HIF-1a expression and regulation in hypoxic pulmonary hypertension (HPH) were reviewed, and current candidate schemes for treating pulmonary hypertension by using HIF-1a as the target were introduced, so as to provide reference for studying the pathogenesis of HPH and screening effective treatment methods.

The Impact of Aging and Toll-like Receptor 2 Deficiency on the Clinical Outcomes of Staphylococcus aureus Bacteremia.

Staphylococcus aureus (S. aureus) causes a broad range of infections. Toll-like receptor (TLR) 2 senses the S. aureus lipoproteins in S. aureus infections. Aging raises the risk of infection. Our aim was to understand how aging and TLR2 affect the clinical outcomes of S. aureus bacteremia. Four groups of mice (wild type/young, wild type/old, TLR2-/-/young, and TLR2-/-/old) were intravenously infected with S. aureus, and the infection course was followed. Both TLR2 deficiency and aging enhanced the susceptibility to disease. Increased age was the main contributing factor for increased mortality rates and changes in spleen weight, whereas other clinical parameters, such as weight loss and kidney abscess formation, were more TLR2 dependent. Importantly, aging increased mortality rates without relying on TLR2. In vitro, both aging and TLR2 deficiency down-regulated cytokine/chemokine production of immune cells with distinct patterns. In summary, we demonstrate that aging and TLR2 deficiency impair the immune response to S. aureus bacteremia in distinct ways.

Multiplex lateral flow test strip for detection of carbapenemase genes using barcoded tetrahedral DNA capture probe-based biosensing interface.

Carbapenem-resistant Enterobacterales pose significant global health challenges due to their rapid spread and ability to hydrolyse various beta-lactam antibiotics. Rapid tests for these carbapenemase genes are crucial to ensure appropriate prescription administration and infection control. In this study, we developed a rapid visual nanodiagnostic platform for multiplexed detection of carbapenemase genes using a lateral flow strip. The nanodiagnostic strip was designed with separate barcoded DNA tetrahedrons for the blaKPC and blaNDM genes. These tetrahedrons were distributed on a nitrocellulose membrane at two different test lines as capture probes. When tested against a panel of carbapenemase genes, the tetrahedral probes captured single-stranded amplicons of asymmetric PCR via strand hybridisation. The amplicons acted as bridging elements, binding the DNA-modified gold nanoparticles to the test line of the strip, resulting in clear visual readouts specific to the blaKPC and blaNDM genes. By employing barcoded tetrahedrons and asymmetric PCR in conjunction with the lateral flow strip, a single diagnostic test enabled the detection of multiple carbapenemase genes. The test yielded results as low as 0.12 fM for blaKPC and 0.05 fM for blaNDM within 75 min. Furthermore, the strip effectively identified specific carbapenemase genes in clinical isolates using real-time PCR, antibody-based lateral flow systems for carbapenemase detection, and carbapenemase phenotype experiments. Thus, the strip develop has a high potential for testing blaKPC and blaNDM genes in practice.

Assessing the spatial variability of raising public risk awareness for the intervention performance of COVID-19 voluntary screening: A spatial simulation approach.

The rapid spread of a (re)emerging pandemic (e.g., COVID-19) is usually attributed to the invisible transmission caused by asymptomatic cases. Health authorities rely on large-scale voluntary screening to identify and isolate invisible spreaders as well as symptomatic people as early as possible to control disease spread. Raising public awareness is beneficial for improving the effectiveness of epidemic prevention because it could increase the usage and demand for testing kits. However, the effectiveness of testing could be influenced by the spatial demand for medical resources in different periods. Spatial demand could also be triggered by public awareness in areas with two geographical factors, including spatial proximity to resources and attractiveness of human mobility. Therefore, it is necessary to explore the spatial variations in raising public awareness on the effectiveness of COVID-19 screening. We implemented spatial simulation models to integrate various levels of public awareness and pandemic dynamics in time and space. Moreover, we also assessed the effects of the spatial proximity of testing kits and the ease of human mobility on COVID-19 testing at various levels of public awareness. Our results indicated that high public awareness promotes high willingness to be tested. This causes the demand to not be fully satisfied at the peak times during a pandemic, yet the shortage of tests does not significantly increase pandemic severity. We also found that when public awareness is low, concentrating on unattractive areas (such as residential or urban fringe areas) could promote a higher benefit of testing. On the other hand, when awareness is high, the factor of distances to testing stations is more important for promoting the benefit of testing; allocating additional testing resources in areas distant from stations could have a higher benefit of testing. This study aims to provide insights for health authorities into the allocation of testing resources against disease outbreaks with respect to various levels of public awareness.

Roles of soluble minerals in Cd sorption onto rice straw biochar.

Transforming to biochar provides an environmentally friendly approach for crop residue reutilization, which are usually applied as sorbent for heavy metal removal. As typical silicon-rich material, the specific sorptive mechanisms of rice straw derived biochar (RSBC) are concerned, especially at the low concentration range which is more environmentally relevant. In the present study, Cd sorption onto RSBCs at the concentration of ≤ 5 mg/L was investigated. The sorptive capacity was positively correlated with the pyrolytic temperature of the biochar and the environmental pH value. Water soluble minerals of the RSBCs played the dominant roles in Cd sorption, contributing 29.2%, 62.5% and 82.9% of the total sorption for RSBCs derived under 300°C, 500°C and 700°C, respectively. Increased number of cations, dominantly K+, were exchanged during the sorption. Coprecipitation with cations and carbonates may also be contributive to the sorption. The dissolution of silicon-containing minerals was found to be declined during sorption, suggesting its involvement in the sorption process, possibly through precipitation. Whilst, the sparingly soluble silicate crystals may impose ignorable role in the sorption. Complexation with organic groups is only a minor mechanism in Cd sorption, compared to the much more dominant roles of the inorganic ashes.

Regionalization for infection control: An algorithm for delineating containment zones considering the regularity of human mobility.

Restricting human movement to decrease contact probability and frequency helps mitigate large-scale epidemics. Movement-based zoning can be implemented to delineate the boundaries for movement restrictions. Previous studies used network community detection methods, which capture cohesive within-region movements, to delineate containment zones. However, most people usually travel and spend most of their time in several fixed locations, which implies that an infected person could transmit the pathogens to only a specific group of people with whom s/he usually has a contact in frequently-visited locations. Existing network community detection methods cannot reflect the regularity of the flow of people; thus, this study aims to use land-use patterns to reflect trip purposes to measure the regularity of human mobility. We propose a novel network community detection method, the Human Mobility Regularity-based Zoning (HuMoRZ) algorithm, to delineate containment zones incorporating mobility regularity. The Taipei metropolitan area in Taiwan is used to demonstrate the feasibility of the proposed algorithm. The spatial diffusion of an emerging respiratory disease, novel influenza A/H1N1, is simulated for comparing three different quarantine zoning systems: (1) a minimum zoning unit, (2) optimal zoning without considering mobility regularity, and (3) optimal zoning considering mobility regularity. Two epidemiological performance indicators are used to compare simulation results: namely, the accumulated infected number (AN) on the 30th day, reflecting the severity of an epidemic, and the critical time (CT), the moment at which half of the population becomes infected, measuring the diffusion speed of an epidemic. To measure the variety of different facility types within a containment zone, we further use Shannon's entropy scores, representing a self-contained zone, and the boxplot of all zones' entropy scores, reflecting geospatial homogeneity of life functions across zones. Our results suggest that containment zones that incorporate mobility regularity could significantly delay the epidemic peak and critical time and decrease the severity of an epidemic. The zoning patterns proposed in our algorithm could also allow for more life functions in a zone and more evenly distributed life resources across zones than those of zones generated by other methods. These findings could provide insightful implications for fighting the COVID-19 pandemic.

Pre-treatment with IL2 gene therapy alleviates Staphylococcus aureus arthritis in mice.

BACKGROUND: Staphylococcus aureus (S. aureus) arthritis is one of the most detrimental joint diseases known and leads to severe joint destruction within days. We hypothesized that the provision of auxiliary immunoregulation via an expanded compartment of T regulatory cells (Tregs) could dampen detrimental aspects of the host immune response whilst preserving its protective nature. Administration of low-dose interleukin 2 (IL2) preferentially expands Tregs, and is being studied as a treatment choice in several autoimmune conditions. We aimed to evaluate the role of IL2 and Tregs in septic arthritis using a well-established mouse model of haematogenously spred S. aureus arthritis. METHODS: C57BL/6 or NMRI mice we intravenously (iv) injected with a defined dose of S. aureus LS-1 or Newman and the role of IL2 and Tregs were assessed by the following approaches: IL2 was endogenously delivered by intraperitoneal injection of a recombinant adeno-associated virus vector (rAAV) before iv S. aureus inoculation; Tregs were depleted before and during S. aureus arthritis using antiCD25 antibodies; Tregs were adoptively transferred before induction of S. aureus arthritis and finally, recombinant IL2 was used as a treatment starting day 3 after S. aureus injection. Studied outcomes included survival, weight change, bacterial clearance, and joint damage. RESULTS: Expansion of Tregs induced by IL2 gene therapy prior to disease onset does not compromise host resistance to S. aureus infection, as the increased proportions of Tregs reduced the arthritis severity as well as the systemic inflammatory response, while simultaneously preserving the host's ability to clear the infection. CONCLUSIONS: Pre-treatment with IL2 gene therapy dampens detrimental immune responses but preserves appropriate host defense, which alleviates S. aureus septic arthritis in a mouse model.

Mass spectrometry imaging: An emerging technology for the analysis of metabolites in insects.

Mass spectrometry imaging (MSI) can visualize the composition, abundance, and spatial distribution of molecules in tissues or cells, which has been widely used in the research of life science. Insects, especially the agricultural pests, have received a great deal of interests from the scientists in biodiversity and food security. This review introduces the major characteristics of MSI, summarizes its application to the investigation of insect endogenous metabolites, exogenous metabolites, and the spatiotemporal changes of metabolites between insects and plants, and discusses its shortfalls and perspectives. The significance of these concerns is beneficial for future insect research such as physiology and metabolism.

Differential Profiles of Gut Microbiota and Metabolites Associated with Host Shift of Plutella xylostella.

Evolutionary and ecological forces are important factors that shape gut microbial profiles in hosts, which can help insects adapt to different environments through modulating their metabolites. However, little is known about how gut microbes and metabolites are altered when lepidopteran pest species switch hosts. In the present study, using 16S-rDNA sequencing and mass spectrometry-based metabolomics, we analyzed the gut microbiota and metabolites of three populations of Plutella xylostella: one feeding on radish (PxR) and two feeding on peas (PxP; with PxP-1 and PxP-17 being the first and 17th generations after host shift from radish to peas, respectively). We found that the diversity of gut microbes in PxP-17 was significantly lower than those in PxR and PxP-1, which indicates a distinct change in gut microbiota after host shift. Kyoto Encyclopedia of Genes and Genomes analysis revealed that the functions of energy metabolism, signal transduction, and xenobiotics biodegradation and metabolism were increased in PxP-17, suggesting their potential roles in host adaptation. Metabolic profiling showed a significant difference in the abundance of gut metabolites between PxR and PxP-17, and significant correlations of gut bacteria with gut metabolites. These findings shed light on the interaction among plants, herbivores, and symbionts, and advance our understanding of host adaptation associated with gut bacteria and metabolic activities in P. xylostella.

Overexpression of P2X4 receptor in Schwann cells promotes motor and sensory functional recovery and remyelination via BDNF secretion after nerve injury.

Of the seven P2X receptor subtypes, P2X4 receptor (P2X4R) is widely distributed in the central nervous system, including in neurons, astrocytes, and microglia. Accumulating evidence supports roles for P2X4R in the central nervous system, including regulating cell excitability, synaptic transmission, and neuropathic pain. However, little information is available about the distribution and function of P2X4R in the peripheral nervous system. In this study, we find that P2X4R is mainly localized in the lysosomes of Schwann cells in the peripheral nervous system. In cultured Schwann cells, TNF-a not only enhances the synthesis of P2X4R protein but also promotes P2X4R trafficking to the surface of Schwann cells. TNF-a-induced BDNF secretion in Schwann cells is P2X4R dependent. in vivo experiments reveal that expression of P2X4R in Schwann cells of injured nerves is strikingly upregulated following nerve crush injury. Moreover, overexpression of P2X4R in Schwann cells by genetic manipulation promotes motor and sensory functional recovery and accelerates nerve remyelination via BDNF release following nerve injury. Our results suggest that enhancement of P2X4R expression in Schwann cells after nerve injury may be an effective approach to facilitate the regrowth and remyelination of injured nerves.

Exploring the differential mechanisms of carotenoid biosynthesis in the yellow peel and red flesh of papaya.

BACKGROUND: Red-fleshed papaya is a good material to study the different carotenoids accumulation mechanism in the peel and flesh. Although the peel and flesh of papaya closely integrated into one body, the flesh coloration changing from white to red, while the exocarp coloration changing from green to yellow. In this study, the major carotenoids accumulation and the expression patterns of key carotenoid biosynthesis pathway genes in the process of papaya fruit ripening were studied, and the carotenoid biosynthetic pathways in the yellow peel and red flesh of papaya were investigated. RESULTS: The carotenoid composition in papaya flesh and peel were different. The major carotenoids were lutein and ß-carotene in the peel, while lycopene in the flesh. The accumulation of carotenoids, including lycopene, ß-carotene, and ß-cryptoxanthin were considered to cause the orange-red color of papaya cv. 'Daqing No.10' flesh. The color of peel changed from green to yellow because of the fast degradation of chlorophyll and the appearance of carotenoids such as lutein and ß-carotene. Thirteen genes that encode enzymes in the carotenoid biosynthetic pathway were detected in papaya fruit transcriptome: two phytoene synthase (PSY1, PSY2), two phytoene desaturase (PDS1, PDS2), one ζ-carotene desaturase (ZDS), four lycopene cyclase (CYCB, LCYB1, LCYB2, LCYE), one ß-carotene hydroxylase (CHYB), one carotene ε-monooxygenase (LUT1), one violaxanthin de-epoxidase (VDE), and one zeaxanthin epoxidase (ZEP). The results of RNA-Seq and RT-qPCR showed the expression of carotenoid biosynthetic pathway genes was consistent with the change of carotenoid content. Carotenoid biosynthetic pathways in the yellow peel and red flesh of papaya were analysed based on the major carotenoids accumulation and the expression patterns of key carotenoid biosynthesis pathway genes. There was only a ß-branch of carotenoid biosynthesis in the flesh of papaya, while there were both α- and ß-branch of carotenoid biosynthesis in papaya peel. In the process of papaya fruit ripening, the α-branch was inhibited and the ß-branch was enhanced in the peel. CONCLUSIONS: The differential carotenoid accumulation and biosynthesis pathway genes expression in peel and flesh, lay a foundation for further study and provide further insights to control fruit color and improve fruit quality and appearance.

Biochar Addition Enhances Phenanthrene Fixation in Sediment.

Biochar is believed to be promising for soil contaminant stabilization due to its large adsorption capacity. However, study in sediment is rare, especially with the aging effect. In the present study, a plant biomass-derived biochar was added to phenanthrene polluted sediment, in order to investigate its performance in sediment remediation. During the incubation period of 60 days, it was observed that the partition coefficient of phenanthrene increased in sediment either with or without biochar addition, as a result of aging process. Whilst, the biochar-added sediments showed much higher partition coefficients, as well as more curved adsorption isotherms, suggesting larger retention of the contaminant. Under the extreme extraction by strong surfactant, the release ratio of phenanthrene from polluted sediment was significantly reduced from 60% to 5% by 0.5% (w/w) addition of biochar. These results suggested that biochar would be applicable for improving the adsorption of organic pollutant in sediment, and the adsorbed organic pollutant would be stably fixed during aging as a result of the increased affinity.

Lack of Receptor for Advanced Glycation End Products Leads to Less Severe Staphylococcal Skin Infection but More Skin Abscesses and Prolonged Wound Healing.

Background: Lack of receptor for advanced glycation end products (RAGE) ameliorates several infections including Staphylococcus aureus pneumonia. We sought to investigate the role of RAGE in staphylococcal skin infection in mice. Methods: Wild-type (WT) and RAGE deficient (RAGE-/-) mice were subcutaneously inoculated with S. aureus SH1000 strain in abscess-forming dose or necrotic dose. Clinical signs of dermatitis, along with histopathological changes, were compared between the groups. Results: The skin lesion size was smaller in RAGE-/- mice. Infected RAGE-/- mice expressed lower proinflammatory cytokines in local skins compared to control mice. Low dose of bacteria caused more abscess formation in RAGE-/- mice compared to skin necrosis that was more often observed in WT mice. As a result of more abscess formation, the wound healing was prolonged in RAGE-/- mice. Importantly, RAGE-/- mice had lower bacterial loads in the skin than controls, which is correlated with higher local levels of myeloperoxidase before skin infection. In vitro, enhanced phagocytic capacity of neutrophils and macrophages obtained from RAGE-/- mice compared to control mice was observed. Conclusions: RAGE deficiency up-regulates phagocytic capacity of phagocytes, resulting in lower bacterial burden in local skin and milder skin lesions in mice with staphylococcal skin infection.

[Correlation study on chemical constitutes of cardiac glycosides in Taxillus chinensis and its Nerium indicum host by UPLC-Q-TOF-MS/MS].

To build up an identification method on cardiac glycosides in Taxillus chinensis and its Nerium indicum host, and evaluate the influence on medicine quality from host to T. chinensis, ultra-performance liquid chromatography coupled with quadrupole-time-of-flight tandem mass-mass spectrometry(UPLC-Q-TOF-MS/MS)was applied. The samples of T. chinensis(harvested from N. indicum)and its N. indicum host were collected in field. The samples of T. chinensis(harvested from Morus alba)and its M. alba host was taken as control substance. All samples were extracted by ultrasonic extraction in 70% ethanol. Chromatographic separation was performed on an ACQUITY UPLC HSS T3 C_(18)(2.1 mm×100 mm,1.8 µm)column at 40 ℃. Gradient elution was applied, and the mobile phase was consisted of 0.1% formic acid water and acetonitrile. The 0.5 µL of sample solution was injected and the flow rate of the mobile phase was kept at 0.6 mL·min~(-1) in each run. It was done to identify cardiac glycosides and explore the chemical composition correlation in T. chinensis and its N. indicum host by analyzing positive and negative ion mode mass spectrometry data, elemental composition, cardiac glycoside reference substance and searching related literatures. A total of 29 cardiac glycosides were identified, 28 of it belonged to N. indicum host, 5 belonged to T. chinensis(harvested from N. indicum host), none of cardiac glycoside was identified in T. chinensis(harvested from M. alba host). The result could provide a reference in evaluating the influence in T. chinensis medicine quality from host. It was rapid, accurate, and comprehensive to identify cardiac glycosides in T. chinensis and its N. indicum host by UPLC-Q-TOF-MS/MS.

Isolation of ripening-related genes from ethylene/1-MCP treated papaya through RNA-seq.

BACKGROUND: Since papaya is a typical climacteric fruit, exogenous ethylene (ETH) applications can induce premature and quicker ripening, while 1-methylcyclopropene (1-MCP) slows down the ripening processes. Differential gene expression in ETH or 1-MCP-treated papaya fruits accounts for the ripening processes. To isolate the key ripening-related genes and better understand fruit ripening mechanisms, transcriptomes of ETH or 1-MCP-treated, and non-treated (Control Group, CG) papaya fruits were sequenced using Illumina Hiseq2500. RESULTS: A total of 18,648 (1-MCP), 19,093 (CG), and 15,321 (ETH) genes were detected, with the genes detected in the ETH-treatment being the least. This suggests that ETH may inhibit the expression of some genes. Based on the differential gene expression (DGE) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, 53 fruit ripening-related genes were selected: 20 cell wall-related genes, 18 chlorophyll and carotenoid metabolism-related genes, four proteinases and their inhibitors, six plant hormone signal transduction pathway genes, four transcription factors, and one senescence-associated gene. Reverse transcription quantitative PCR (RT-qPCR) analyses confirmed the results of RNA-seq and verified that the expression pattern of six genes is consistent with the fruit senescence process. Based on the expression profiling of genes in carbohydrate metabolic process, chlorophyll metabolism pathway, and carotenoid metabolism pathway, the mechanism of pulp softening and coloration of papaya was deduced and discussed. We illustrate that papaya fruit softening is a complex process with significant cell wall hydrolases, such as pectinases, cellulases, and hemicellulases involved in the process. Exogenous ethylene accelerates the coloration of papaya changing from green to yellow. This is likely due to the inhibition of chlorophyll biosynthesis and the α-branch of carotenoid metabolism. Chy-b may play an important role in the yellow color of papaya fruit. CONCLUSIONS: Comparing the differential gene expression in ETH/1-MCP-treated papaya using RNA-seq is a sound approach to isolate ripening-related genes. The results of this study can improve our understanding of papaya fruit ripening molecular mechanism and reveal candidate fruit ripening-related genes for further research.

Role of Diabetes Mellitus on Treatment Effects in Drug-susceptible Initial Pulmonary Tuberculosis Patients in China.

We assessed the role of diabetes mellitus (DM) on treatment effects in drug-susceptible initial pulmonary tuberculosis (PTB) patients. A prospective study was conducted in eight provinces of China from October 2008 to December 2010. We enrolled 1,313 confirmed drug-susceptible initial PTB patients, and all subjects received the treatment regimen (2H3R3E3Z3/4H3R3) as recommended by the national guidelines. Of the 1,313 PTB patients, 157 (11.9%) had DM; these patients had more sputum smear-positive rates at the end of the second month [adjusted odds ratios (aOR) 2.829, 95% confidence intervals (CI) 1.783-4.490], and higher treatment failure (aOR 2.120, 95% CI 1.565-3.477) and death rates (aOR 1.536, 95% CI 1.011-2.628). DM was a contributing factor for culture-positive rates at the end of the second month and treatment failure and death of PTB patients, thus playing an unfavorable role in treatment effects of PTB.

Effects of electromagnetic fields exposure on plasma hormonal and inflammatory pathway biomarkers in male workers of a power plant.

PURPOSE: The potential health risks of electromagnetic fields (EMFs) have currently raised considerable public concerns. The aim of this study was to evaluate the effects of EMF exposure on levels of plasma hormonal and inflammatory pathway biomarkers in male workers of an electric power plant. METHODS: Seventy-seven male workers with high occupational EMF exposure and 77 male controls with low exposure, matched by age, were selected from a cross-sectional study. Moreover, high EMF exposure group was with walkie-talkies usage and exposed to power frequency EMF at the work places for a longer duration than control group. A questionnaire was applied to obtain relevant information, including sociodemographic characteristics, lifestyle factors, and EMF exposures. Plasma levels of testosterone, estradiol, melatonin, NF-κB, heat-shock protein (HSP) 70, HSP27, and TET1 were determined by an enzyme-linked immunosorbent assay. RESULTS: EMF exposure group had statistically significantly lower levels of testosterone (ß = -0.3 nmol/L, P = 0.015), testosterone/estradiol (T/E2) ratio (ß = -15.6, P = 0.037), and NF-κB (ß = -20.8 ng/L, P = 0.045) than control group. Moreover, joint effects between occupational EMF exposure and employment duration, mobile phone fees, years of mobile phone usage, and electric fees on levels of testosterone and T/E2 ratio were observed. Nevertheless, no statistically significant associations of EMF exposures with plasma estradiol, melatonin, HSP70, HSP27, and TET1 were found. CONCLUSIONS: The findings showed that chronic exposure to EMF could decrease male plasma testosterone and T/E2 ratio, and it might possibly affect reproductive functions in males. No significant associations of EMF exposure with inflammatory pathway biomarkers were found.

Risk of Treatment Failure in Patients with Drug-susceptible Pulmonary Tuberculosis in China.

The objective of this prospective study of the risks of treatment failure in patients with drug-susceptible pulmonary tuberculosis (PTB) was to provide reference data to help develop a disease control strategy. Participants were recruited in eight provinces of China from October 2008 to December 2010. A total of 1447 patients with drug-susceptible PTB and older than 15 years of age were enrolled. Demographic characteristics, bacteriological test results, and patient outcome, i.e., cure or treatment failure were recorded and compared using the chi-square or Fisher's exact tests. Multivariate logistic regression was used to identify factors associated with risk of treatment failure. Of the 1447 patients who were enrolled, 1349 patients (93.2%) were successfully treated and 98 (6.8%) failed treatment. Failure was significantly associated with age 365 years [odds ratio (OR)=2.522, 95% confidence interval (CI): (1.097-5.801)], retreatment [OR=2.365, 95% CI: (1.276-4.381)], missed medicine [OR=1.836, 95% CI: (1.020-3.306)], treatment not observed [OR=1.879 95% CI: (1.105-3.195)], and positive culture result after the first [OR=1.971, 95% CI: (1.080-3.597)] and second month [OR=4.659, 95% CI: (2.590-8.382)]. The risk factors associated with treatment failure were age 365 years, retreatment, missed medication, treatment not observed, and positive culture at the end of month 1 or month 2. These risk factors should be monitored during treatment and interventions carried out to reduce or prevent treatment failure and optimize treatment success.

[Bloodstream infections in southwestern China: 2012 Whire Union report on bacterial susceptibility to antibiotics].

OBJECTIVE: To test the susceptibility of blood culture isolates to antibiotics in a sample of hospitals in Southwestern China in 2012. METHODS: Blood culture samples were taken and tested from the patients under the Whire Union surveillance in three tertiary hospitals in Southwestern China in 2012. We performed antimicrobial susceptibility analyses on the blood culture isolates using WHONET5. 5 and SPSS19.0. RESULTS: A total of 1745 isolates were identified: 877 Gram-positive (50.26%); 868 Gram-negative (49.74%). Coagulase-negative Staphylococcius (CNS, 541 strains, 31.00%), Escherichia coli (ECO, 379 strains, 21.72%), Klebsiella spp. (170 strains, 9.74%), Enterococcus spp. (143 strains, 8.20%) and Staphylococcus aureus (SAU, 128 strains, 7.34%) comprised the majority of isolates. Methicillin-resistant was found in 37.5% of S. aureus and 85.4% of CNS, respectively. Zero and 6.3% resistance to vancomycin were found for Enterococcus faecalis and E. faecium, respectively,compared with a 1.4% and 7.9% resistance to linezolid, respectively. Imipenem-resistance occurred in 0.7% E. coli, 3.6% Klebsiella spp., and 11.1% Enterobacter spp.. Nonfermenters were highly resistant to carbapenems, with an imipenem resistance rate of 25.0% in P. aeruginosa and 79.1% in Acinetobacter baumannii. Antimicrobial usage and critical-care units were identified as risk factors for MRSA and multi-drug-resistant A. baumannii infections. Patients undergoing tracheotomy/endotracheal intubation were likely to develop multi-drug-resistant A. baumannii infections than others. CONCLUSION: CNS, E. coli,Klebsiella spp., Enterococcus spp. and S. aureus were the predominant organisms in bloodstream infections in Southwestern China. Low methicillin-resistant rate was found in Staphylococcus aureus. But vancomycin-resistant rate was high in E. faecium. Imipenem-resistant rates varied in Enterobacteriaceae: higher in non-fermenting bacteria especially in Acinetobacter spp. Use of abtimicrobial drugs and invasive procedures can lead to development of antimicrobial drugs-resistance.