Evidence for a quantum spin Hall phase in graphene decorated with Bi2Te3 nanoparticles.

Realization of the quantum spin Hall effect in graphene devices has remained an outstanding challenge dating back to the inception of the field of topological insulators. Graphene's exceptionally weak spin-orbit coupling-stemming from carbon's low mass-poses the primary obstacle. We experimentally and theoretically study artificially enhanced spin-orbit coupling in graphene via random decoration with dilute Bi2Te3 nanoparticles. Multiterminal resistance measurements suggest the presence of helical edge states characteristic of a quantum spin Hall phase; the magnetic field and temperature dependence of the resistance peaks, x-ray photoelectron spectra, scanning tunneling spectroscopy, and first-principles calculations further support this scenario. These observations highlight a pathway to spintronics and quantum information applications in graphene-based quantum spin Hall platforms.

The impact of nutritional state on the duration of sputum positivity of Mycobacterium tuberculosis.

BACKGROUND: The outcome of anti-tuberculosis treatment varies according to patient factors. OBJECTIVE: To retrospectively identify risks related to the extension of time to negative sputum culture (Tn) and to determine their clinical significance. DESIGN: Patients with bacilli susceptible to isoniazid and rifampicin who received initial standard treatment without cessation were recruited into the study. A total of 630 consecutive in-patients were included in the risk development analysis (development cohort) and another 611 consecutive in-patients in the risk validation analysis (validation cohort). RESULTS: Univariate analysis showed that Tn was related to sex, body mass index (BMI), white blood cell count (WBC), serum albumin, fasting blood sugar, haemoglobin A1c, C-reactive protein and total cholesterol levels and sputum smear positivity (SSP). Multivariate analysis showed that BMI, WBC and SSP were significant risk factors related to extended Tn. Optimal cut-offs of BMI and WBC for predicting good (Tn < 46 days) and poor responders (Tn ⩾ 46 days) according to each risk were determined by receiver operating characteristics analysis. Risks were verified with the validation cohort. Tn increased according to the number of risks; the median Tn for patients with three risks was 21 days longer than that of patients with none. CONCLUSION: The nutritional state of a TB patient can be used to predict Tn.

The impact of nutrition and glucose intolerance on the development of tuberculosis in Japan.

BACKGROUND: Although Japan is categorised as an intermediate tuberculosis (TB) burden country, the incidence of TB is nevertheless decreasing. OBJECTIVE: To identify metabolic and nutritional risk factors for the development of TB. DESIGN: We compared 522 TB in-patients (350 males, 172 females) with age- and sex-matched 522 controls randomly selected from among individuals undergoing comprehensive medical examinations. Patients with relapsed or multidrug-resistant TB were excluded. RESULT: The proportion of males with glucose intolerance was significantly higher in TB patients than in controls (34.2% vs. 14.4%). Among females, the proportion with glucose intolerance was higher in TB patients than in controls (18.3% vs. 10.0%). In male and female controls and female TB patients, individuals with glucose intolerance had significantly higher body mass index (BMI) than those without glucose intolerance. Low BMI was prevalent in male TB patients; there was no significant difference between the BMIs of TB patients with glucose intolerance and those without. Significant associations were found between BMI, peripheral white blood cell count, serum albumin concentration and glucose intolerance and the development of TB in males. Albumin was a parameter significantly associated with TB development in females. CONCLUSION: In Japan, the development of TB is still associated with glucose intolerance and malnutrition.

[Antimicrobial effect of human endometrial peroxidase on Escherichia coli and Staphylococcus aureus].

Human endometrium had potent peroxidase activity and an antimicrobial effect. Relationships which existed between the human endometrial peroxidase and antimicrobial effect were studied. Human endometrial peroxidase activity was measured by the modified method of Himmelhoch. In the normal menstrual cycle, the peroxidase activity in the secretory phase was higher than in the proliferative phase. The peroxidase activity in endometrial carcinoma was remarkably higher than in the normal menstrual cycle. The organisms (E.coli, S.aureus) and peroxidase extract were incubated for 60 min at 37 degrees C. Bacterial viability was determined by the plate culture method. The viable cell count was decreased. Endometrial peroxidase had an antimicrobial effect on E.coli and S.aureus. But the antimicrobial effect on clinically isolated S.aureus exerted by the peroxidase was not effective. Although the peroxidase activity in the endometrial carcinoma was higher than in the normal endometrium, there was no detectable antimicrobial effect. Peroxidase of endometrial carcinoma was suspected of having some different characteristics from normal endometrium.