Identification of early Al-responsive genes in rice bean (Vigna umbellata) roots provides new clues to molecular mechanisms of Al toxicity and tolerance.

Significant secretion of citrate from root apex of rice bean (Vigna umbellata) is delayed by several hours under aluminium (Al) stress. However, the molecular basis of regulation of VuMATE1, a gene encoding an Al-activated citrate transporter, remains unclear. In this study, we used suppression subtractive hybridization together with reverse northern blot analysis and qRT-PCR to identify genes with altered transcript levels in the root apex after treatment with low (5 µm) or high (25 µm) concentration of AlCl(3) for a short time (4 h). We found that in addition to VuMATE1, 393 genes showed an early response to Al. Among functionally annotated genes, those related to 'metabolism and energy', 'signal transduction and transcription' and 'transport' was predominantly up-regulated, whereas those associated with 'protein translation, processing and degradation' was predominantly down-regulated. Comparative analysis of transcriptional profiles highlighted candidate genes associated with citrate secretion and revealed several new aspects of the molecular processes underlying Al toxicity and tolerance. Based on the data, it is proposed that metabolic changes represent adaptive mechanisms to Al stress, whereas inhibition of both cell elongation and cell division underlies Al-induced root growth inhibition.

Decreased risk of developing lung cancer in subjects carrying the CLPTM1L rs401681 (G>A) polymorphism: evidence from a meta-analysis.

A genome-wide association study revealed that a single nucleotide polymorphism, CLPTM1L - rs401681 (G>A), located at the 5p15.33 locus was significantly associated with increased risk of various cancers; however, its association with lung cancer is currently inconclusive. In order to explore the relationship between this polymorphism and lung cancer risk more precisely, we performed a meta-analysis of eight eligible studies involving 9935 cases and 11,261 controls. The pooled odds ratio (OR) and the 95% confidence interval (CI) were calculated using a fixed- or random-effect models. Results indicated that this polymorphism was significantly associated with lung cancer risk in all genetic models (GA vs GG: OR = 0.88, 95%CI = 0.83-0.94; AA vs GG: OR = 0.81, 95%CI = 0.70-0.93; AA/GA vs GG: OR = 0.86, 95%CI = 0.81-0.91; AA vs GA/GG: OR = 0.86, 95%CI = 0.76-0.99). An analysis stratified by ethnicity and source of controls revealed a significantly decreased risk among European groups and population-based studies in all genetic models, and among Asian populations only in the dominant model comparison. Additionally, in a subgroup analysis by histology type, the CLPTM1L rs401681 polymorphism was found to significantly decrease the risks of both adenocarcinoma and squamous cell carcinoma of the lung in all genetic models. In conclusion, our study indicated that the CLPTM1L - rs401681 (G>A) polymorphism was significantly associated with decreased lung cancer risk, especially among European populations. Due to some minor limitations, our findings should be confirmed in further studies.

Saccharomyces cerevisiae Live Cells Decreased In vitro Methane Production in Intestinal Content of Pigs.

An in vitro gas production technique was used in this study to elucidate the effect of two strains of active live yeast on methane (CH4) production in the large intestinal content of pigs to provide an insight to whether active live yeast could suppress CH4 production in the hindgut of pigs. Treatments used in this study include blank (no substrate and no live yeast cells), control (no live yeast cells) and yeast (YST) supplementation groups (supplemented with live yeast cells, YST1 or YST2). The yeast cultures contained 1.8×10(10) cells per g, which were added at the rates of 0.2 mg and 0.4 mg per ml of the fermented inoculum. Large intestinal contents were collected from 2 Duroc×Landrace×Yorkshire pigs, mixed with a phosphate buffer (1:2), and incubated anaerobically at 39°C for 24 h using 500 mg substrate (dry matter (DM) basis). Total gas and CH4 production decreased (p<0.05) with supplementation of yeast. The methane production reduction potential (MRP) was calculated by assuming net methane concentration for the control as 100%. The MRP of yeast 2 was more than 25%. Compared with the control group, in vitro DM digestibility (IVDMD) and total volatile fatty acids (VFA) concentration increased (p<0.05) in 0.4 mg/ml YST1 and 0.2 mg/ml YST2 supplementation groups. Proportion of propionate, butyrate and valerate increased (p<0.05), but that of acetate decreased (p<0.05), which led to a decreased (p<0.05) acetate: propionate (A: P) ratio in the both YST2 treatments and the 0.4 mg/ml YST 1 supplementation groups. Hydrogen recovery decreased (p<0.05) with yeast supplementation. Quantity of methanogenic archaea per milliliter of inoculum decreased (p<0.05) with yeast supplementation after 24 h of incubation. Our results suggest that live yeast cells suppressed in vitro CH4 production when inoculated into the large intestinal contents of pigs and shifted the fermentation pattern to favor propionate production together with an increased population of acetogenic bacteria, both of which serve as a competitive pathway for the available H2 resulting in the reduction of methanogenic archaea.

[Plasmids carried by carbapenems-resistant Klebsiella pneumoniae in burn patients and its correlation with strain transmission].

Objective: To explore the carrier status of carbapenems-resistant Klebsiella pneumoniae (CRKP) plasmids in burn patients and analyze the correlation of these plasmids with the transmission of CRKP. Methods: A retrospective observational study was conducted. A total of 26 CRKP strains, which were isolated from the clinic-related samples of 22 burn patients (with 20 males and 2 females, aged (42±16) years) admitted to the First Affiliated Hospital of Army Medical University (the Third Military Medical University) from January to December 2017, were collected and individually numbered. The plasmids of the strains were extracted by alkali lysis. After determination of the plasmid concentration by a nucleic acid concentration detector, the agarose gel electrophoresis was used to visualize the bands, and rough plasmids typing was performed. The plasmid of the smallest numbered CRKP in each plasmid type was transformed into competent Escherichia coli (E. coli) strain Top10 (hereinafter referred to as TOP10 strain). The growth of each transformed strains and a Top10 strain cultivated in ampicillin containing Luria-Bertani (LB) agar medium overnight was observed, and the proportion of successful transformation was calculated. The plasmids from the smallest numbered plasmid carrying CRKP strain of successfully transformed Top10 strains (hereinafter referred to as the smallest successfully transformed strain) and correspondingly numbered CRKP were extracted, and then, the agarose gel electrophoresis was used to visualize the bands. Aforementioned successfully transformed strains and a TOP10 strain were used for the antimicrobial susceptibility testing with 17 antibiotics commonly used in clinic. The plasmid from the smallest successfully transformed strain was sequenced using the next-generation sequencing technology. Bioinformatics analyses such as protein-coding gene prediction and protein sequence alignment were performed successively. The sequence was subsequently named pKP03-NDM1 according to the carrying of drug resistance gene. According to the whole genome sequence of the plasmid carried by the smallest successfully transformed strain, the polymerase chain reaction, agarose gel electrophoresis, and gene sequencing were used to detect the New Delhi metallo-beta lactamase-1 (blaNDM-1) of plasmids in the remaining 25 strains of CRKP. The ST typing in multilocus sequence typing of 26 strains of CRKP was analyzed based on the literature. Results: Plasmids were successfully extracted from 26 CRKP, with mass concentrations ranging from 19.3 to 189.8 ng/µL. Each of the 26 CRKP carrying plasmids showed at least one band longer than 2 500 bp in the agarose gel electrophoresis, which were roughly divided into 6 patterns of A, B, C, D, E, and F. After overnight cultivation, no growth of strains was observed in LB agar medium containing ampicillin inoculated with the TOP10 strain or TOP10 strains transformed by the plasmid of CRKP patterning A, B, D, or E. In contrast, TOP10 strains transformed by the pattern C plasmid from NO.3 CRKP and the pattern F plasmid from NO.15 CRKP resulted in numerous colony growths, and those transformed strains were named as TOP10-pKP03 and TOP10-pKP15, respectively. The proportion of successful transformation was 1/3. The plasmid carried by TOP10-pKP03 showed a single band in the agarose gel electrophoresis, which was the same size as the largest band of the plasmid from NO.3 CRKP. The TOP10 strain was sensitive to the 17 antibiotics commonly used in clinic. TOP10-pKP03 and TOP10-pKP15 were resistant to penicillins, cephalosporins, and carbapenems but remained sensitive to monocyclic ß-lactam, aminoglycosides, quinolones and tigecycline. The full length of the plasmid carried by TOP10-pKP03 was 41 190 bp. In addition to blaNDM-1, this plasmid carried bleMBL, T4SS, bleomycin resistance gene, conjugation transfer elements, and relaxase, etc. The plasmid showed 99% nucleotide identity similarity and the same length to the plasmid pJN24NDM1 extracted from an E. coli isolate JN24. Totally 16 (61.5%) CRKP were confirmed to carrying blaNDM-1 gene, among the ST typing of the 16 strains, 11 strains were ST11, while ST215, ST260, ST395, ST2230, and new ST had 1 strain each. Among the ST typing of 10 blaNDM-1-negative CRKP, 8 strains were ST11, while ST395 and ST2230 had 1 strain each. Conclusions: A blaNDM-1 gene carrying plasmid pKP03-NDM1 was extracted and sequenced from CRKP isolated from burn patients, with a high plasmid carrying rate. Meanwhile, this plasmid may mediate inter-CRKP and CRKP-E. coli horizontal transfer of blaNDM-1, leading to transmission of antimicrobial resistance.

Lysophosphatidic acid (LPA) and endothelial differentiation gene (Edg) receptors in human pancreatic cancer.

Lysophosphatidic acid (LPA) is a naturally occurring phospholipid with diverse effects on various cells, ranging from immediate morphological change to long-lasting cellular function alteration such as induction of stimulation of cell proliferation, survival, drug resistance, and motility. LPA interacts with cells through specific cell surface receptors. LPA1/Edg-2, LPA2/Edg-4, and LPA3/Edg-7 are three most common LPA receptors. Herein we review the roles of LPA and its receptors in the carcinogenesis of human malignancies, with focus on pancreatic cancer.

Long-term survival case of a non-small cell lung cancer bone metastasis patient treated with bone cement, radiation and gefitinib.

OBJECTIVE: We explore the treatment of bone metastases in advanced non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: We reported a 76-year-old female patient, who was diagnosed with NSCLC with bone metastasis eight years ago (stage IVA). Due to unbearable diarrhea, she refused chemotherapy, and we adopted local treatment, including local radiotherapy 50 Gy and bone cement to lumbar spinal metastases, 62 Gy local radiotherapy of primary lung tumor, TKI inhibitor gefitinib and zoledronic acid. RESULTS: She survived more than eight years and is still in follow-up. CONCLUSIONS: The median survival time for NSCLC patients with bone metastases is often less than 1 year. We reported the patient with more than eight years of survival, showed that some special cases can adopt the methods of local treatment including bone cement, treatment benefit patients, radiation therapy and targeted therapy in clinic to expand the survival.

[Epidemiological investigation and analysis of etiological characteristics of infection on 3 067 hospitalized pediatric patients with burns].

Objective: To investigate the epidemiological characteristics and etiological distribution of infection on 3 067 hospitalized pediatric patients with burns, and explore the prevention and treatment strategy of pediatric burns. Methods: A cross-sectional survey was conducted. An analysis was performed on the data of 3 067 hospitalized pediatric patients with burns who met the inclusion criteria and were admitted to the First Affiliated Hospital of Army Medical University (the Third Military Medical University) from January 2012 to December 2020, including gender, age, causative factors, locations and severities of burns, seasons of accidents, and the type, source of tissue or body fluid, and drug resistance of pathogenic bacteria. API bacterial identification batten and automatic microbial identification system were applied for pathogen identification. Drug sensitivities of top 3 consistent ratio pathogen identifed were tested with minimum inhibitory concentration and disk diffusion method. WHONET 5.6 software was applied to analyze the data. Results: There were 3 067 hospitalized pediatric patients with burns, including 1 768 boys and 1 299 girls. The majority of pediatric burn patients were >1 and ≤4 years, accounting for 72.9% (2 236/3 067), and the minority of pediatric burn patients were >8 and ≤12 years, accounting for 4.9% (150/3 067). Moderate burns and severe burns of pediatric burn patients accounted for the majority parts, and the proportions of the two were close. The top cause of pediatric burns was scald, accounting for 81.6% (2504/3 067). Extremities were the most common burn sites in that of entire 3 254. The most pediatric burns occurred in winter, accounting for 29.4% (903/3 067). A total of 1 018 strains of pathogenic bacteria were collected from pediatric burn patients, all of which were non-repeated isolates. The pathogens with top five consistent ratio were Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, Enterobacter cloacae, and Escherichia coli, among which Staphylococcus aureus ranked the first every year. The pathogens were mainly isolated from the wound exudate, accounting for 81.34% (828/1 018). Staphylococcus aureus from 2012 to 2020 showed no resistance to vancomycin, linezolid or teicoplanin while Staphylococcus aureus isolated in 2019 was 100% resistant to macrolides, penicillin, aminoglycosides, and quinolones. Pseudomonas aeruginosa was not resistant to polymyxin B. Acinetobacter baumannii showed a high rate of drug resistance to most antibiotics. Conclusions: Among the pediatric burn patients admitted to the First Affiliated Hospital of Army Medical University (the Third Military Medical University) from 2012 to 2020, the majority are male children aged >1 and ≤4 years with moderate burns. Scalds are the leading cause; and extremities are the common burn sites; and the most pediatric burns occurre in winter. Staphylococcus aureus from wound exudate is the primary pathogen of burn wound infections in pediatric patients.

[Work flow of clinical microbiology laboratory in the epidemic of the coronavirus disease 2019].

The burn microbiology laboratory of the author's unit is a level Ⅱ biosafety laboratory, which is mainly responsible for handling clinical microbial samples from our department and other departments in the hospital. Since the outbreak of the coronavirus disease 2019, in order to ensure the normal operation of routine work and the safety of medical staff, the microbiology laboratory has actively adjusted the daily work flow. The detailed work flow is summarized as follows to provide references for the safety protection of peer in clinical microbiology laboratory.

[Analysis of distribution and drug resistance of pathogens isolated from 159 patients with catheter-related bloodstream infection in burn intensive care unit].

Objective: To analyze the distribution and drug resistance of pathogens isolated from patients with catheter-related bloodstream infection (CRBSI) in burn intensive care unit (BICU). Methods: From January 2011 to December 2018, among 2 264 patients who were peripherally inserted central venous catheter at the BICU of the First Affiliated Hospital of Army Medical University (the third Military Medical University), hereinafter referred to as the author's unit, 159 patients were diagnosed CRBSI, including 131 males and 28 females, aged 43 (1, 79) years. The pathogens primarily isolated from peripheral venous blood and central venous catheter blood/anterior central venous catheter specimen of patients with CRBSI were retrospectively analyzed. API bacteria identification kits and automatic microorganism identification instrument were used to identify pathogens. Broth micro-dilution method or Kirby-Bauer paper disk diffusion method was used to detect the drug resistance of the pathogens to 5 antifungal drugs including fluconazole and itraconazole, etc., and 37 antibacterial drugs including tigecycline and imipenem, etc. Modified Hodge test was used to further identify imipenem- and meropenem-resistant Klebsiella pneumonia. D test was used to detect erythromycin-induced clindamycin resistant Staphylococcus aureus. The WHONET 5.6 software was applied to analyze the annual incidence of CRBSI, mortality of patients with CRBSI, incidence of CRBSI cases, distribution of infection site, and duration of catheterization, detection of Gram-negative and Gram-positive bacteria, fungi, methicillin-resistant Staphylococcus aureus (MRSA), and methicillin-sensitive Staphylococcus aureus (MSSA), and drug resistance of fungi and major Gram-negative and Gram-positive bacteria to the commonly used antibiotics in clinic. Results: (1) The incidence of CRBSI was 7.0% (159/2 264) during the eight years, which was slightly higher in 2014 and 2017 with 13.6% (30/221) and 11.1% (24/217) respectively. The mortality rate of patients with CRBSI was 7.5% (12/159). (2) The incidence of CRBSI cases was 14.9% (338/2 264); the main infection site was femoral vein, totally 271 cases (80.2%), and the duration of catheterization of this site was 9 (2, 25) d. (3) During the eight years, totally 543 strains of pathogens were isolated, including 353 (65.0%) strains of Gram-negative bacteria, 140 (25.8%) strains of Gram-positive bacteria, and 50 (9.2%) strains of fungi. The top three isolated pathogens with isolation rate from high to low were Acinetobacter baumannii, Staphylococcus aureus, and Pseudomonas aeruginosa, accounting for 23.2% (126/543), 17.1% (93/543), and 15.7% (85/543), respectively. Fungi were mainly Candida parapsilosis. Among the Staphylococcus aureus, the detection rate of MRSA was 98.9% (92/93), and that of MSSA was 1.1% (1/93). (4) Except for the low drug resistance rates to polymyxin B, minocycline, and tigecycline, the drug resistance rates of Acinetobacter baumannii to the other antibiotics were considerably high (80.1%-100.0%). Pseudomonas aeruginosa was not resistant to polymyxin B but highly resistant to netilmicin (88.7%) and piperacillin (92.6%), with resistance rates to the other antibiotics from 34.5% to 62.7%. Klebsiella pneumoniae was not resistant to tigecycline and lowly resistant to imipenem and meropenem (28.9%, 9 imipenem- and meropenem-resistant strains were further confirmed by modified Hodge test), with resistance rates to the other antibiotics from 40.9% to 95.2%. The resistance rates of MRSA to most antibiotics were higher than those of MSSA. MRSA was not resistant to linezolid, vancomycin, teicoplanin, sulfamethoxazole, or tigecycline. The resistance rates of MRSA to clindamycin and erythromycin were 7.9% and 62.0%, respectively, and those to the other antibiotics were higher than 91.5%. Except for the complete resistance to penicillin G and tetracycline, MSSA was not resistant to the other antibiotics. Thirty-three strains of Staphylococcus aureus showed resistance to erythromycin-induced clindamycin. Fungi was not resistant to amphotericin B, with drug resistance rates to voriconazole, itraconazole, ketoconazole, and fluconazole from 4.2% to 6.2%. Conclusions: The incidence of CRBSI and mortality of patients with CRBSI are high in BICU of the author's unit, and the main infection site is femoral vein. There are various types of pathogens in patients with CRBSI, and most of them are Gram-negative. The top three isolated pathogens are Acinetobacter baumannii, Staphylococcus aureus, and Pseudomonas aeruginosa, accompanying with grim drug resistance phenomenon.

[Analysis of the pathogenic characteristics of fungal bloodstream infection in severe burn patients].

Objective: To retrospectively analyze the diagnosis time, pathogen distribution, and drug resistance of fungal bloodstream infection in severe burn patients. Methods: Blood samples were collected from 55 severe burn patients with fungal bloodstream infection (including 46 males and 9 females, aged 42 (1, 78) years) admitted to the intensive care unit of the Institute of Burn Research of the First Affiliated Hospital of Army Medical University (the Third Military Medical University) from July 2011 to May 2019 for retrospective analysis. Microbial monitoring system was used to cultivate pathogens, API yeast identification kit and Candida chromogenic medium were used to identify pathogens, and Kirby-Bauer paper disk diffusion method was used to detect drug resistance of fungi to fluconazole, amphotericin B, itraconazole, ketoconazole, and voriconazole. The positive rate of blood fungal culture, mortality rate, distribution of local fungal proliferation sites, the diagnosis time distribution of fungal bloodstream infection, the distribution of fungal species, resistance to commonly-used antifungal drugs, and the use of antibiotics were assessed. The WHONET 5.6 software was applied to analyze the distribution and drug resistance of fungi. Results: (1) Totally 4 839 blood samples were collected during the 9 years, and 122 strains of fungi were isolated, with positive rate of 2.52%. The mortality rate was 14.55% (8 patients) in 55 patients. Catheter fungal proliferation ranked the first among 30 cases of local fungal proliferation. (2) The diagnosis time of fungal bloodstream infection mainly distributed in ≤1 week of hospitalization [32.73% (18/55)]. (3) Among the 55 strains of fungi detected, the detection rate of Candida parapsilosis ranked the first (21.82%, 12 strains), Candida glabrata was the second (18.18%, 10 strains), and Candida tropicalis was tied with Candida albicans in the third place (14.55%, 8 strains). All the detected fungi were sensitive to amphotericin B, and the resistance rates to voriconazole, fluconazole, itraconazole, and ketoconazole were between 4.5% and 9.1%. (4) Droad-spectrum antibiotics were used in all the 55 patients, ≥3 kinds of antibiotics were used in 44 patients, and 37 patients used antibacterial drugs ≥7 days. Conclusions: The diagnosis time of fungal bloodstream infection in the 55 severe burn patients was mainly within 1 week of hospitalization. Candida parapsilosis is the most commonly detected fungal species. Catheter fungal proliferation occurs most commonly among the 30 patients with local fungal proliferation. All the detected fungi were sensitive to amphotericin B, with low drug resistance to voriconazole, fluconazole, itraconazole, and ketoconazole. Broad-spectrum antibiotics were overused in the severe burn patients with fungal bloodstream infection.