99 research outputs found
Identification and Characterization of a Dual-Acting Antinematodal Agent against the Pinewood Nematode, Bursaphelenchus xylophilus
The pinewood nematode (PWN), Bursaphelenchus xylophilus, is a mycophagous and phytophagous pathogen responsible for the current widespread epidemic of the pine wilt disease, which has become a major threat to pine forests throughout the world. Despite the availability of several preventive trunk-injection agents, no therapeutic trunk-injection agent for eradication of PWN currently exists. In the characterization of basic physiological properties of B. xylophilus YB-1 isolates, we established a high-throughput screening (HTS) method that identifies potential hits within approximately 7 h. Using this HTS method, we screened 206 compounds with known activities, mostly antifungal, for antinematodal activities and identified HWY-4213 (1-n-undecyl-2-[2-fluorphenyl] methyl-3,4-dihydro-6,7-dimethoxy-isoquinolinium chloride), a highly water-soluble protoberberine derivative, as a potent nematicidal and antifungal agent. When tested on 4 year-old pinewood seedlings that were infected with YB-1 isolates, HWY-4213 exhibited a potent therapeutic nematicidal activity. Further tests of screening 39 Caenorhabditis elegans mutants deficient in channel proteins and B. xylophilus sensitivity to Ca2+ channel blockers suggested that HWY-4213 targets the calcium channel proteins. Our study marks a technical breakthrough by developing a novel HTS method that leads to the discovery HWY-4213 as a dual-acting antinematodal and antifungal compound
Screening for Chlamydia and Gonorrhea by Strand Displacement Amplification in Homeless Adolescents Attending Youth Shelters in Korea
We conducted the screening of sexually transmitted infections to define the prevalence of genital Chlamydia trachomatis and Neisseria gonorrhoeae infections and status of sexual risk behavior among homeless adolescents (10-19 yr old) in Korea. Adolescents who ran away from home and are under the care of youth shelters in ten cities in Korea served as the study population. Participants filled out a self-administered questionnaire related to sexuality. First-void urine was analyzed for chlamydial and gonococcal infection by strand displacement amplification (BDProbTecTMET, BD Diagnostic Systems, MD, U.S.A.). A total of 175 adolescents from 15 youth shelters took part in the study. Their median age was 16 yr, and 54.9% of them reported having sexual intercourse at least once. The prevalence of C. trachomatis and N. gonorrhoeae among homeless adolescents was 12.6% and 15.4%, respectively. Factors significantly associated with the infections were number of sexual partners during the past year and lifetime. This is the first community-based sexually transmitted infection (STI) screening among adolescent in Korea. Screening programs targeting sexually active adolescents are important for detection of STIs. They should be considered an alternative population-based surveillance system in order to control STIs nationally
Usefulness of Multiplex Real-Time PCR for Simultaneous Pathogen Detection and Resistance Profiling of Staphylococcal Bacteremia
Staphylococci are the leading cause of nosocomial blood stream infections. Fast and accurate identification of staphylococci and confirmation of their methicillin resistance are crucial for immediate treatment with effective antibiotics. A multiplex real-time PCR assay that targets mecA, femA specific for S. aureus, femA specific for S. epidermidis, 16S rRNA for universal bacteria, and 16S rRNA specific for staphylococci was developed and evaluated with 290 clinical blood culture samples containing Grampositive cocci in clusters (GPCC). For the 262 blood cultures identified to the species level with the MicroScan WalkAway system (Siemens Healthcare Diagnostics, USA), the direct real-time PCR assay of positive blood cultures showed very good agreement for the categorization of staphylococci into methicillin-resistant S. aureus (MRSA), methicillin-susceptible S. aureus (MSSA), methicillin-resistant S. epidermidis (MRSE), methicillin-susceptible S. epidermidis (MSSE), methicillin-resistant non-S. epidermidis CoNS (MRCoNS), and methicillin-susceptible non-S. epidermidis CoNS (MSCoNS) ( = 0.9313). The direct multiplex real-time PCR assay of positive blood cultures containing GPCC can provide essential information at the critical point of infection with a turnaround time of no more than 4 h. Further studies should evaluate the clinical outcome of using this rapid real-time PCR assay in glycopeptide antibiotic therapy in clinical settings
Anti-inflammatory and Immune-regulatory Effects of Subcutaneous Perillae Fructus Extract Injections on OVA-induced Asthma in Mice
Perillae fructus (perilla seed) is a traditional medicinal herb used to treat bronchial asthma in Oriental medical clinics. ST36 is one of the most widely used acupuncture points, particularly for immune system regulation. Injection of an herbal extract into an acupuncture point (herbal acupuncture) is a therapeutic technique combining both acupuncture and herbal treatment. Perillae fructus extract was injected subcutaneously (Perillae fructus herbal acupuncture; PF-HA) at acupoint ST36 of OVA-induced asthmatic mice. The lung weight, bronchoalveolar fluid (BALF) cell count, the number of CCR3+, CD11b+, CD4+ and CD3e+/CD69+ cells in the lung, and the level of IgE, IL-4, IL-5 and IL-13 in BALF and serum were then measured. RT-PCR was used to measure the mRNA expression of IL-4, IL-5, IL-13 and TNF-α in the lung. Lung sections were analyzed histologically. PF-HA significantly reduced lung weight, the number of inflammatory cells in the lung and BALF, the levels of IgE and Th2 cytokines in BALF and serum, mRNA expression of Th2 cytokines in the lung, and pathological changes in lung tissue. Our results suggest that PF-HA may have an anti-inflammatory and immune-regulatory effect on bronchial allergic asthma by restoring the Th1/Th2 imbalance in the immune system and suppressing eosinophilic inflammation in airways
Psychometric Validation of the Korean Version of Structured Interview for Post-traumatic Stress Disorder (K-SIP)
For diagnosis and management of post-traumatic stress disorder (PTSD), the easily administered assessment tool is essential. Structured Interview for PTSD (SIP) is a validated, 17-item, simple measurement being used widely. We aimed to develop the Korean version of SIP (K-SIP) and investigated its psychometric properties. Ninety-three subjects with PTSD, 73 subjects with mood disorder or anxiety disorder as a psychiatric control group, and 88 subjects as a healthy control group were enrolled in this study. All subjects completed psychometric assessments that included the K-SIP, the Korean versions of the Clinician-Administered PTSD Scale (CAPS) and other assessment tools. The K-SIP presented good internal consistency (Cronbach's α=0.92) and test-retest reliability (r=0.87). K-SIP showed strong correlations with CAPS (r=0.72). Among three groups including PTSD patients, psychiatric controls, and normal controls, there were significant differences in the K-SIP total score. The potential cut-off total score of K-SIP was 20 with highest diagnostic efficiency (91.9%). At this point, the sensitivity and specificity were 95.5% and 88.4%, respectively. Our result showed that K-SIP had good reliability and validity. We expect that K-SIP will be used as a simple but structured instrument for assessment of PTSD
The CpG island methylator phenotype may confer a survival benefit in patients with stage II or III colorectal carcinomas receiving fluoropyrimidine-based adjuvant chemotherapy
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