Incidence of and risk factors for active tuberculosis in human immunodeficiency virus-infected patients in South Korea

BACKGROUND

In South Korea, a high-income country with an intermediate tuberculosis (TB) burden and low human immunodeficiency virus (HIV) prevalence, studies on incidence and risk factors of TB in HIV-infected persons have rarely been reported.

OBJECTIVE

To investigate the incidence of and risk factors for active TB in HIV-infected persons in South Korea.

METHODS

A retrospective analysis was conducted of 1265 HIV-1 infected patients who visited four hospitals in South Korea between 1985 and 2012. We analysed the incidence of TB during the follow-up period. To investigate risk factors associated with active TB, we conducted a 1:2 matched case-control study of HIV-infected patients with newly active TB and controls without active TB who had similar CD4(+) T-cell counts and dates of first visit.

RESULTS

Over a total of 4457 person-years (py), 185 (14.6%) subjects were diagnosed with active TB; the incidence was 4.2 cases/100 py. In multivariate analysis, low body mass index (P = 0.033) and current smoking (P = 0.003) were independent risk factors for TB in HIV-infected patients.

CONCLUSION

Further strategies on prevention and treatment of active TB among HIV-infected patients should be implemented in South Korea. Encouraging smoking cessation and supporting good nutrition may be ways to reduce the incidence of active TB in HIV-infected patients.

The association between coronary artery calcification and colorectal adenoma

BACKGROUND/AIMS

Both colorectal neoplasm and coronary artery disease are prevalent diseases worldwide and share several risk factors. The aim of this study was to investigate the association between coronary artery calcification and prevalence of colorectal adenoma.

METHODOLOGY

We retrospectively evaluated 3,092 subjects who underwent colonoscopy and coronary artery calcium computed tomography (CT) on the same day or within a 3-month interval, during routine check-ups between January 2006 and June 2009 at the Center for Health Promotion of the Samsung Medical Center. Multivariate logistic regression analysis was used to calculate adjusted odds ratios (ORs).

RESULTS

Colorectal adenomas were detected in 1,067 (34.5%) of the 3,092 subjects, including 536 (41.0%) individuals with and 531 (29.7%) without coronary calcification (p<0.001). Multiple logistic regression analysis showed that the presence of coronary artery calcification (OR=1.346; 95% confidence interval [CI]=1.122-1.614), age ≥50 years (OR=1.516; 95% CI=1.256-1.829), waist circumference of 90-99cm (OR=1.364; 95% CI=1.008-1.844) and current smoker (OR=1.266; 95% CI=1.045-1.534) were associated with the prevalence of colorectal adenoma.

CONCLUSIONS

The prevalence of colorectal adenoma is significantly higher in patients with coronary artery calcification. Our results support positive relationship between coronary artery disease and colorectal adenoma.

A phase II study of neoadjuvant docetaxel, oxaliplatin, and S-1 (DOS) chemotherapy followed by surgery and adjuvant S-1 chemotherapy in potentially resectable gastric or gastroesophageal junction adenocarcinoma

PURPOSE

Adjuvant chemotherapy trial of TS-1 for gastric cancer study demonstrated that postoperative S-1 chemotherapy for 1 year improved overall survival of locally advanced gastric cancer (LAGC) patients. The goals of this study were to evaluate the feasibility and efficacy of neoadjuvant docetaxel, oxaliplatin, and S-1 (DOS) chemotherapy followed by surgery and adjuvant S-1 chemotherapy.

METHODS

In this single-center, open-label, phase II study, patients with potentially resectable adenocarcinoma of the stomach or gastroesophageal junction were eligible. For neoadjuvant chemotherapy, docetaxel 50 mg/m(2) on day (D) 1, oxaliplatin 100 mg/m(2) on D1, and S-1 40 mg/m(2) bid orally on D1-14 were administrated every 3 weeks for three cycles. After DOS chemotherapy, gastrectomy was performed, and then, adjuvant S-1 40 mg/m(2) bid was given on D1-28 every 6 weeks for 1 year. The primary endpoints were the proportion of patients who did not experience grade 3 or 4 toxicities (except grade 3 neutropenia) and R0 resection rates.

RESULTS

A total of 41 patients were enrolled. All patients completed three planned cycles of neoadjuvant chemotherapy without disease progression. Eighteen patients (43.9 %) did not experience any grade 3-4 toxicity (except grade 3 neutropenia) during the neoadjuvant chemotherapy. All patients underwent surgery, and R0 resection was achieved in 40 patients (97.6 %).

CONCLUSION

Neoadjuvant DOS chemotherapy could be performed safely with a high R0 resection rate in LAGC patients. A phase III trial is currently underway.

A ginseng metabolite, compound K, induces autophagy and apoptosis via generation of reactive oxygen species and activation of JNK in human colon cancer cells

Compound K (20-O-(β-D-glucopyranosyl)-20(S)-protopanaxadiol) is an active metabolite of ginsenosides and induces apoptosis in various types of cancer cells. This study investigated the role of autophagy in compound K-induced cell death of human HCT-116 colon cancer cells. Compound K activated an autophagy pathway characterized by the accumulation of vesicles, the increased positive acridine orange-stained cells, the accumulation of LC3-II, and the elevation of autophagic flux. Whereas blockade of compound K-induced autophagy by 3-methyladenein and bafilomycin A1 significantly increased cell viability. In addition, compound K augmented the time-dependent expression of the autophagy-related proteins Atg5, Atg6, and Atg7. However, knockdown of Atg5, Atg6, and Atg7 markedly inhibited the detrimental impact of compound K on LC3-II accumulation and cell vitality. Compound K-provoked autophagy was also linked to the generation of intracellular reactive oxygen species (ROS); both of these processes were mitigated by the pre-treatment of cells with the antioxidant N-acetylcysteine. Moreover, compound K activated the c-Jun NH2-terminal kinase (JNK) signaling pathway, whereas downregulation of JNK by its specific inhibitor SP600125 or by small interfering RNA against JNK attenuated autophagy-mediated cell death in response to compound K. Compound K also provoked apoptosis, as evidenced by an increased number of apoptotic bodies and sub-G1 hypodiploid cells, enhanced activation of caspase-3 and caspase-9, and modulation of Bcl-2 and Bcl-2-associated X protein expression. Notably, compound K-stimulated autophagy as well as apoptosis was induced by disrupting the interaction between Atg6 and Bcl-2. Taken together, these results indicate that the induction of autophagy and apoptosis by compound K is mediated through ROS generation and JNK activation in human colon cancer cells.

Synthesis and biological activity of 4,5-polymethylenepyrazole-derived HMG-COA reductase inhibitors

New HMG-CoA reductase inhibitors, in which 3-substituted 4,5-polymethylenepyrazoles are employed as a hydrophobic anchor connected to tetrahydro-4-hydroxy-2H-pyran-2-one by a two-carbon bridge, were designed and synthesized to exhibit significant inhibitory activity comparable to mevinolin. The most potent enzyme inhibitor (11cc, IC(50)=0.01 muM) is 4-fold more potent than lovastatin.

A novel nortriterpene fromHedera rhombea

A new nortriterpene, rhombenone (1) was isolated from the leaves ofHedera rhombea Bean (Araliaceae). The structure of this compound was established as 27-demethyl-20(S)-dammar-23-ene-6alpha,20-diol-3,25-dione on the basis of spectral analysis including HMQC and HMBC techniques. Rhombenone (1) was the first 27-demethyl nortriterpene of dammarance type isolated from natural sources.