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OBJECTIVES: The routes of human infection with Helicobacter pylori remain unclear. In the present study, we examined cockroaches as possible vectors for transmission of H. pylori. METHODS: We used a common species of cockroach (Periplaneta fuliginosa). After a 3-day fast, cockroaches were placed on agar plates containing freshly grown H. pylori (Sydney strain) (challenge group) or on sterile agar plates without H. pylori (control group). After 24 h of challenge, cockroaches were moved to disinfected containers, and sterile food and water were provided. The external surfaces (legs and body) and excreta of the cockroaches were sampled for culture, rapid urease test, and polymerase chain reaction (PCR). RESULTS: H. pylori were culturable from the excreta of the challenge group for 24 h postchallenge. Positive rapid urease test results were obtained up to day 3, and PCR analysis was positive for H. pylori DNA up to day 7 from the excreta. In contrast, H. pylori were not culturable from the external surfaces of the cockroaches. The rapid urease test was positive for only 8 h, and PCR analysis was positive for H. pylori DNA for 1 day from the external surface. CONCLUSIONS: Cockroaches usually live in unsanitary environments and may contaminate foods and food containment areas such as pantries. Transmission of H. pylori infection could be achieved via inadvertent ingestion of foods contaminated with cockroach excreta containing viable H. pylori.  相似文献   
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The electrical properties of CdTe layers electrodeposited from an acidic sulfate aqueous electrolyte were examined by resistivity and Hall effect measurements. It was revealed that the resistivity, conduction type, and carrier density of the as-deposited CdTe layers could be controlled by the deposition potential. The resistivity varied in the range from 2 × 106 to 2 × 108 Ω cm. The CdTe layers deposited at potentials slightly positive to the Cd2+/Cd equilibrium potential (?0.37 V vs. SHE?E??0.30 V) had n-type conductions, while those deposited at more positive potentials (?0.15 V ?E??0.05 V) were p-type. The carrier densities of the CdTe layers were on the order of 1010–1011 cm?3. As the deposition potential became more positive, the electron density decreased, and conversely, the hole density increased. The electron mobilities for the n-type CdTe layers were in the range 7–40 cm2 V?1 s?1, while the hole mobility was about 1 cm2 V?1 s?1.  相似文献   
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BACKGROUND: Elevated mean corpuscular volume (MCV) is a traditional biological marker for alcohol abuse and alcoholism, but the underlying mechanism is unclear. Three recent epidemiologic studies consistently showed that MCV was elevated by alcohol drinking more markedly among individuals with genetically inactive aldehyde dehydrogenase-2 (ALDH2) (encoded by ALDH2*2 mutant allele) than those with active ALDH2 (encoded by ALDH2*1/2*1 genotype), suggesting that the elevated MCV was etiologically linked to acetaldehyde exposure. The purpose of the present study was to clarify further this relationship by examining the status of folate and vitamin B12. METHODS: The study participants were 159 men who were aged 40 to 69 years and randomly selected from a Japanese rural population. The genetic polymorphism of ALDH2 was determined by PCR-restriction fragment length polymorphism method; data on alcohol drinking and other lifestyles were collected using a structured questionnaire; serum concentrations of folate and vitamin B12 were measured using the protein competitive reaction method, and blood cell counts were measured by routine methods. A multiple linear regression model was used to analyze the data. RESULTS:: The relationship between alcohol drinking and serum folate concentration was significantly different between ALDH2 genotypes, indicating that the reduction of serum folate by alcohol drinking was more marked in men with ALDH2*1/2*2 than those with ALDH2*1/2*1. The relationship between alcohol drinking and elevated MCV was significantly stronger in men with ALDH2*1/2*2 than those with ALDH2*1/2*1 even after adjustment for serum folate and vitamin B12 concentrations. CONCLUSIONS: These findings indicate that acetaldehyde plays a significant role in the development of decreased serum folate concentration and elevated MCV by alcohol drinking.  相似文献   
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Type A insulin resistance (IR) syndrome is a severe IR form caused by insulin receptor (INSR) gene defects. Antidiabetic drugs, including high‐dose insulin and insulin‐sensitizing agents, often fail to control associated hyperglycemia. Therapy with recombinant human insulin‐like growth factor 1 can be more effective, but it is expensive. We report a case of type A IR syndrome with an in‐frame INSR heterozygous deletion (ΔLeu999) that was treated with a combination of conventional therapy and ipragliflozin, a sodium–glucose cotransporter 2 inhibitor. Treatment reduced hemoglobin A1c levels (10.0–7.5%) and induced weight loss (54.4–52.0 kg) within 2 months, and the effects were sustained for >3 years. Sodium–glucose cotransporter 2 inhibitors might be useful to normalize blood glucose in type A IR syndrome by reducing bodyweight and ameliorating glucotoxicity.  相似文献   
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Aim: More than 5-year clinical outcomes after femoropopliteal (FP) stenting with bare-nitinol stent (BNS) have not yet been unclear. We investigate the long-term patency and mortality following FP stenting with BNS. Methods: This study was a multicenter retrospective study of a prospectively maintained database. From April 2004 to December 2011, 1824 consecutive patients (2211 limbs) who underwent FP stenting with BNS for de novo lesions were selected and analyzed. Primary endpoint was primary patency which was defined as treated vessel without restenosis and reintervention and its associated factors. Results: The prevalence of diabetes mellitus and dialysis was 60.5% and 23.8%, respectively. Chronic limb-threatening ischemia (CLTI) accounted for 30.8%. Chronic total occlusion (CTO) was found in 52.7%, and lesion length was more than 20 cm in 22.6%. During the median follow-up of 3.8 years (interquartile range, 1.4 to 7.4 years), 1049 cases lost patency, whereas 355 cases were dead without experiencing loss of patency. The primary patency (95% CI) was estimated to be 74.8%, 47.3% and 29.1% at 1-, 5- and 10-year. On multivariate analysis, female sex, age ≥ 80 years, diabetes, dialysis, CLTI, CTO, arterial calcification, long lesion (>20 cm), and small vessel (≤ 4 mm) were the independent predictors of primary patency after FP stenting. In addition, the prognostic impact of age ≥ 80 years, CLTI, and arterial calcification was significantly attenuated afterwards (P<0.05). Conclusions: Ten-year patency after BNS implantation for FP disease has been continuously reducing up to 10 years and the prognostic impact of risk factors was changed over time.  相似文献   
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