[A survey of deployment of sidewalks in central urban areas of 12 cities, China]

Objective: To explore the deployment of sidewalks and the possible relationship with local GDP, population density and prosperity of streets in 12 cities selected in China. Methods: For all the streets in 333 blocks of 12 cities surveyed (Beijing, Tianjin, Shanghai, Qingdao, Hangzhou, Shaoxing, Suzhou, Nantong, Zhenjiang, Chengdu, Xining and Harbin), the deployment and management of sidewalks were observed. And we collected the GDP data of the 12 cities, the population data of 333 blocks, and the numbers of stores and restaurants along the streets. Results: A total of 4 255 streets were included in the study. In the 12 cities, 71.1% of the streets had sidewalks. The deployment rates of sidewalks was high in Qingdao (91.9%) and Harbin (90.6%), and low in Suzhou (48.6%) and Shaoxing (52.6%), the differences were significant. The higher GDP of city was, the more sidewalks were deployed. But on the other hand there were more parking cars and obstacles on the sidewalks. The higher the population density was, the worse the condition of sidewalks was. Conclusions: The survey of sidewalks in the 12 cities indicated that efforts could be made to improve the condition of sidewalks. Attention should be paid not only to the deployment of sidewalks, but also the management of sidewalks. Reasonable deployment of sidewalks should be considered according to the local population density and traffic flow.

[Influences of genetic and environmental factors on smoking related behaviors among male twin adults in China]

OBJECTIVE

To analyze the influences of genetic and environmental factors on smoking behavior, smoking cessation and onset age of smoking less than 20 years in male twin adults.

METHODS

A face-to-face questionnaire was conducted to collect data from 6 458 pair male twins aged ≥25 years registered in 9 provinces(municipality)in China. The heritability of three smoking related behaviors were calculated by using structural equation models.

RESULTS

The ACE models were the best models of the three dimensions of smoking, i.e. smoking behavior, smoking cessation and onset age of smoking less than 20 years for male twins, and the corresponding heritability of these behaviors were 0.26(0.19-0.34), 0.27(0.19-0.37)and 0.05(0.00-0.14), respectively. When adjusted for area and age, the heritability of these three behaviors were 0.26(0.19-0.34), 0.31(0.00-0.74)and 0.05(0.00-0.14), respectively.

CONCLUSIONS

All the three smoking related behaviors were affected by genetic factors, but environment factors had more effect on them. For smoking cessation, the heritability was highest, but the influence of environmental factors was lowest. Meanwhile, for onset age of smoking, the influence of environmental factors was highest.

Insulin-like Growth Factor 1 Regulates the Expression of ATP-Binding Cassette Transporter A1 in Pancreatic Beta Cells

ATP-binding cassette transporter A1 (ABCA1) in pancreatic beta cells influences insulin secretion and cholesterol homeostasis. The present study investigates whether insulin-like growth factor 1 (IGF-1), which mediates stimulation of ABCA1 gene expression, could also interfere with the phosphatidylinositol 3-kinase (PI3-K) cascade.ABCA1 expression was examined by real-time polymerase chain reaction (PCR), Western blot analysis, and a reporter gene assay in rat insulin-secreting INS-1 cells incubated with IGF-1. The binding of forkhead box O1 (FoxO1) protein to the ABCA1 promoter was assessed by a chromatin immunoprecipitation (ChIP) assay. ABCA1 protein levels increased in response to rising concentrations of IGF-1. Real-time PCR analysis showed a significant increase in ABCA1 mRNA expression. However, both effects were suppressed after silencing the IGF-1 receptor. In parallel with its effect on endogenous ABCA1 mRNA levels, IGF-1 induced the activity of a reporter construct containing the ABCA1 promoter, while it was abrogated by LY294002, a specific inhibitor of PI3-K. Constitutively active Akt stimulated activity of the ABCA1 promoter, and a dominant-negative mutant of Akt or mutagenesis of the FoxO1 response element in the ABCA1 promoter abolished the ability of IGF-1 to stimulate promoter activity. A ChIP assay showed that FoxO1 mediated its transcriptional activity by directly binding to the ABCA1 promoter region. The knockdown of FoxO1 disrupted the effect of IGF-1 on ABCA1 expression. Furthermore, IGF-1 promoted cholesterol efflux and reduced the pancreatic lipotoxicity. These results demonstrate that the PI3-K/Akt/FoxO1 pathway contributes to the regulation of ABCA1 expression in response to IGF-1 stimulation.

Simplified ab externo fixation technique to treat late dislocation of scleral-sutured polymethyl methacrylate intraocular lenses

PurposeWe report a simplified ab externo scleral fixation technique to manage the late dislocation of scleral-sutured polymethyl methacrylate (PMMA) intraocular lenses (IOLs) in the absence of capsule support.Materials and methodsThe technique was performed on five eyes of five patients. Symmetrical scleral pocket tunnels without conjunctival peritomy were created. An anterior vitrectomy via a limbal approach with an anterior chamber infusion or a 3-port pars plana vitrectomy was performed to rescue the dislocated IOL. A long straight suture needle and 23-gauge vitreoretinal forceps were used to conveniently reposition the IOL and loop sutures through the IOL positioning eyelets without externalizing IOL haptics. The outside suture knots were buried under the roof of the scleral tunnels.ResultsThe patients were followed for 5-14 months after surgery. All the operated eyes quickly recovered with negligible corneal endothelial cell loss and mild inflammation. Visual acuity improvement and IOL centration were achieved in all eyes with no major complications.ConclusionThe simplified ab externo scleral fixation technique offers an effective and minimally invasive surgical alternative to salvage dislocated previously scleral-sutured PMMA IOLs.

GenoType® MTBDRplus assay detection of drug-resistant tuberculosis in routine practice in Korea

SETTING

Korea is an intermediate-burden country with high rates of tuberculosis (TB) drug resistance.

OBJECTIVE

To evaluate the performance of the GenoType® MTBDRplus (MTBDR) assay in diagnosing drug-resistant TB in routine practice in Korea.

DESIGN

The MTBDR assay was performed on 428 samples, and the results were retrospectively compared with the results of conventional drug susceptibility testing (DST). The interval between treatment and diagnosis of drug resistance was also compared.

RESULTS

The sensitivity, specificity and positive and negative predictive values of the MTBDR assay were respectively 96.6%, 98.9%, 93.4% and 99.5% for the detection of rifampicin (RMP) resistance; 93.8%, 98.3%, 92.7% and 98.6% for isoniazid (INH) resistance; and 91.1%, 99.2%, 99.4% and 98.7% for multidrug-resistant TB (MDR-TB). The median interval between the start of anti-tuberculosis chemotherapy and the reporting of results was 88.9 days for conventional DST and 19.8 days for MTBDR using clinical specimens.

CONCLUSION

The specificity of the MTBDR assay in detecting MDR-TB was very high, although the sensitivity in detecting INH resistance and MDR-TB was not optimal (<95%). Although the turnaround time in detecting drug resistance was dramatically reduced with MTBDR compared to conventional DST, more effort is needed to shorten the turnaround time.

Distinguishing tuberculosis from Mycobacterium avium complex disease using an interferon-gamma release assay

SETTING

The QuantiFERON-TB Gold (QFT-G) test can be used to distinguish between tuberculosis (TB) and non-tuberculous mycobacterial disease, but a high background TB infection rate may pose a problem. Although the QuantiFERON-TB (QFT) test, the first-generation QFT-G test, employs a non-specific PPD antigen, avium sensitin is also used as a stimulating antigen.

OBJECTIVE

To evaluate the utility of these two interferon gamma release assays (IGRAs), QFT-G and QFT, and the tuberculin skin test (TST), to differentiate TB from Mycobacterium avium complex (MAC) disease in an intermediate TB burden country.

METHODS

We compared the diagnostic performance of these three tests in 38 prospectively enrolled patients with TB and 40 with MAC lung disease.

RESULTS

The TST yielded positive results in 70.6% of TB and 47.5% of MAC patients; the proportions were respectively 89.5% and 34.3% for QFT-G and 86.8% and 35.3% for QFT. The three tests were of similar accuracy, sensitivity and specificity in diagnosing TB.

CONCLUSION

Our findings indicate that the TST and IGRAs could not discriminate between active TB and MAC disease or latent TB infection in a TB-endemic area.

Non-tuberculous mycobacterial diseases presenting as solitary pulmonary nodules

SETTING

South Korea, 2005-2007.

BACKGROUND

Non-tuberculous mycobacterial diseases presenting as solitary pulmonary nodules (NTM-SPN) are rare and may be misdiagnosed as tuberculoma.

DESIGN

Eleven NTM-SPN patients were enrolled retrospectively and compared with two groups each of 33 patients with upper lobe cavitary (UC) and nodular bronchiectatic (NB) type NTM diseases, respectively.

RESULTS

The patients' median age was 52 years. Compared with UC-type disease, NTM-SPN patients showed female (n = 9) and never smoker (n = 8) predominance and fewer comorbidities (n = 0; P < 0.05 for each). Mycobacterium avium (n = 9) was predominant in NTM-SPN patients, followed by M. intracellulare (n = 2), whereas M. intracellulare was most frequently isolated from patients with both UC- and NB-type NTM (P < 0.05). The nodules were a median of 2.3 cm in diameter (range 1.6-6.3 cm) and were distributed evenly in all lobes. In all patients, percutaneous needle aspiration/biopsy was performed with a median 71 days of diagnostic delay. Ten patients successfully completed treatment, and one showed spontaneous reduction of nodule size without treatment. Reverse blot hybridisation assays of six DNA samples identified four subjects with M.avium-intracellulare complex (MAC), in line with conventional test data.

CONCLUSION

NTM-SPN was caused exclusively by MAC. Although clinical outcome was favourable, confirmatory diagnosis was delayed. Molecular methods are needed for early diagnosis of NTM-SPN.