Biomedical subjects

Yujun Wu

Publications and source records attributed to Yujun Wu.

4 recordsLinked to original sources

PubMed2024

In-situ enrichment of ARGs and their carriers in soil by hydroxamate siderophore: A promising biocontrol approach for source reduction.

Pathogenic microorganisms with antibiotic resistance genes (ARGs) pose a serious threat to public health and soil ecology. Although new drugs and available antibacterial materials can kill ARG carriers but accidentally kill beneficial microorganisms. Therefore, the rapid enrichment and separation of ARGs and their carriers from soil is becoming an important strategy for controlling the diffusion of ARGs. Hydroxamate siderophore (HDS) has gained widespread attentions for its involvement in trace element transfer among microorganisms in the soil environment, we thus explored an in-situ trapping-enrichment method for ARGs and their carriers via a small molecular HDS secreted by Pseudomonas fluorescens HMP01. In this study, we demonstrate that HDS significantly in-situ traps and enriches certain ARGs, including chloramphenicol, MLS, rifamycin, and tetracycline resistance genes in the soil environment. The enrichment efficiencies were 1473-fold, 38-fold, 17-fold, and 5-fold, respectively, higher than those in the control group. Specifically, the primary enriched ARGs were rpoB, mphL, catB2, and tetA(60), and Bacillus, Rhizobium, Rossellomorea, and Agrobacterium were hosts for these ARGs. This enrichment was caused by the upregulation of chemotaxis genes (e.g., cheW, cheC, and cheD) and rapid biofilm formation within the enriched bacterial population. Notably, representative ARGs such as cat, macB, and rpoB were significantly reduced by 36%, 85.7%, and 72%, respectively, in the paddy soil after HDS enrichment. Our research sheds light on the potential application of siderophore as a rapping agent for the eco-friendly reduction of ARGs and their carriers in soil environments.

Soil Microbiology↗

PubMed2006

Rational drug sequencing of paclitaxel, gemcitabine and carboplatin in patients with untreated stage IV and select stage IIIB non-small cell lung cancer.

INTRODUCTION: To conduct a phase II study evaluating the efficacy of rationally sequenced paclitaxel, gemcitabine, and carboplatin in patients with stage IV or select stage IIIB non-small cell lung cancer (NSCLC). METHODS: Patients with select stages IIIB (pleural effusion) and IV NSCLC with an ECOG performance status of 0-1 and no prior chemotherapy for their disease were eligible to participate. Treatment was delivered as follows: paclitaxel at 70 mg/m2 followed by gemcitabine at 300 mg/m2 on day 1, with carboplatin (AUC 5) on day 2 of a 28-day cycle. Response was assessed after every two cycles of therapy. The primary endpoint of this trial was response rate, with secondary endpoints of time to progression and 1 year overall survival. RESULTS: Twenty patients were enrolled on protocol, one of whom never received chemotherapy. The median number of cycles delivered was 3 (range 0-8). A partial response rate of 42% (8/19; 95% CI: 20-67%) and a stable disease rate of 11% (2/19; 95% CI: 1-33%) were observed. The median overall survival time was 9.6 months (95% CI: 4.6-16.6), with a 1 year overall survival rate of 42.1% (95% CI: 24.9-71.3%). Eight patients (42%) stopped treatment due to toxicity. CONCLUSION: Paclitaxel followed by gemcitabine and then carboplatin is an active, albeit complex, regimen in the treatment of patients with advanced NSCLC with insufficient advantage to justify continuation of this regimen.

Aged↗

PubMed2006

A multivariate two-sample mean test for small sample size and missing data.

We develop a new statistic for testing the equality of two multivariate mean vectors. A scaled chi-squared distribution is proposed as an approximating null distribution. Because the test statistic is based on componentwise statistics, it has the advantage over Hotelling's T2 test of being applicable to the case where the dimension of an observation exceeds the number of observations. An appealing feature of the new test is its ability to handle missing data by relying on only componentwise sample moments. Monte Carlo studies indicate good power compared to Hotelling's T2 and a recently proposed test by Srivastava (2004, Technical Report, University of Toronto). The test is applied to drug discovery data.

Algorithms↗

PubMed2005

Strong correlation between meiotic crossovers and haplotype structure in a 2.5-Mb region on the long arm of chromosome 21.

Although the haplotype structure of the human genome has been studied in great detail, very little is known about the mechanisms underlying its formation. To investigate the role of meiotic recombination on haplotype block formation, single nucleotide polymorphisms were selected at a high density from a 2.5-Mb region of human chromosome 21. Direct analysis of meiotic recombination by high-throughput multiplex genotyping of 662 single sperm identifies 41 recombinants. The crossovers were nonrandomly distributed within 16 small areas. All, except one, of these crossovers fall in areas where the haplotype structure exhibits breakdown, displaying a strong statistically positive association between crossovers and haplotype block breaks. The data also indicate a particular clustered distribution of recombination hotspots within the region. This finding supports the hypothesis that meiotic recombination makes a primary contribution to haplotype block formation in the human genome.

Chromosome Mapping↗