Genotype profiles of Helicobacter pylori from gastric biopsies and strains with antimicrobial-induced resistance.

BACKGROUND AND AIMS: The genotypic method could significantly shorten the time needed to obtain antibiotic susceptibility data for Helicobacter pylori. The aim of this study was to explore the profile of H. pylori from gastric biopsies and strains with antibiotic-induced resistance. METHODS: A total of 124 gastric biopsies were used to perform gene sequencing and to perform bacterial culture and susceptibility testing. Seven susceptible strains were selected to develop resistance to clarithromycin, levofloxacin, and metronidazole. Four susceptible strains were selected to transfer candidate mutations. The genotype profiles of these groups were analyzed by sequencing analysis. The antibiotic susceptibility of these strains was detected using the E-test method. RESULTS: Phenotypic resistance to clarithromycin, levofloxacin, and metronidazole was observed in 35.5%, 40.0%, and 79.8% strains, respectively. Point mutations in 23 S rRNA, gyrA, and rdxA genes were observed in 39.5%, 38.7%, and 86.3% of gastric biopsies, respectively. The A2143G mutation in the 23S rRNA occurs in most clarithromycin-resistant samples. The A2142C point mutation showed a higher efficacy than A2142G and A2143G for inducing clarithromycin resistance. The D91N and N87K mutations in gyrA occurs in most levofloxacin-resistant samples, and double point mutations showed a higher efficacy than single mutations for inducing levofloxacin resistance. Phenotypic resistance and mutations in rdxA lacked consistency. CONCLUSION: Genotype-based gastric biopsy analysis was reliable for determining clarithromycin and levofloxacin resistance. A2143G in 23S rRNA and N87K/D91N in the gyrA gene occurred in most resistant strains. Mutations in the rdxA gene were not good indicators of metronidazole resistance.

[Preparation of angiopep-2-modified FITC-labeled neurotoxin nanoparticles and in vitro release characteristics].

In order to prepare angiopep-2 modified fluorescein isothiocyanate-labeled neurotoxin nanoparticles( ANG-NPs/FITCNT),emulsion/solvent evaporation method was used with m PEG-PLA and ANG-PEG-PLA( in proper proportions) as carriers and with FITC-NT as drug. With particle size and encapsulation efficiency as comprehensive indexes,the effects of different ultrasound power and ultrasound time combinations on the process were investigated. The in vitro release characteristics of nanoparticles in PBS buffer at p H 7. 4 and p H 6. 5 were investigated by dialysis method. The results indicated that the optimum process for preparing ANG-NPs/FITC-NT was as follows: ultrasonic power 90 W,ultrasonic time 30 s. In such optimal process,ANG-NPs/FITC-NT were well-shaped under the transmission electron microscope,with an average particle size of( 123. 9±0. 5) nm,Zeta potential of(-10. 5±0. 5) m V,encapsulation efficiency of( 68. 1±0. 4) %,and the drug loading of( 0. 82±0. 01) %. The in vitro drug release profiles of the nanoparticles in PBS buffer at p H 7. 4 and p H 6. 5 were both consistent with Ritger-Peppas equation,ln Q = 0. 508 8 lnt-2. 285 0,r = 0. 961 5( p H 7. 4) and ln Q= 0. 449 9 lnt-1. 855 3,r = 0. 970 3( p H 6. 5),respectively. The experiment results proved that the nanoparticles prepared by emulsion/solvent evaporation method had uniform particle size,high encapsulation efficiency and in vitro sustained release characteristic,which might be a potential carrier for NT intracerebral drug delivery.

Dichloroacetate induces protective autophagy in esophageal squamous carcinoma cells.

Dichloroacetate (DCA) is an inhibitor of pyruvate dehydrogenase kinase, which promotes the flux of carbohydrates into mitochondria and enhances the aerobic oxidation of glucose. DCA has previously been demonstrated to exhibit antitumor properties. The present study revealed that treatment with DCA induced increased levels of autophagy-associated proteins in esophageal squamous carcinoma cells while minimally affecting apoptosis. The present study examined the localization of light chain (LC)-3 by adenovirus infection with a green fluorescent protein (FP)-red FP-LC3 reporter construction and confirmed that DCA treatment induced significant autophagy. Furthermore, the inhibition of DCA-induced autophagy facilitated cell apoptosis and improved the drug sensitivity of esophageal squamous carcinoma cells to DCA and 5-FU (5-fluorouracil). The proliferation of TE-1 cells was markedly inhibited at low concentrations of DCA and 5-FU treatment when subjected to Atg5 mRNA interference, indicating that autophagy performed a protective role in cell survival upon DCA treatment. To determine the underlying mechanism of DCA-induced autophagy, the present study measured alterations in autophagy-associated signaling pathways. Notably, the protein kinase B (Akt)-mechanistic target of rapamycin (mTOR) signaling pathway, an important negative regulator of autophagy, was demonstrated to be suppressed by DCA treatment. These results may direct the development of novel strategies for the treatment of esophageal squamous carcinoma based on the combined use of DCA and autophagy inhibitors.

Comparison of two different size needles in endoscopic ultrasound-guided fine-needle aspiration for diagnosing solid pancreatic lesions: A meta-analysis of prospective controlled trials.

BACKGROUND: This meta-analysis aimed to provide a pooled analysis of prospective controlled trials comparing the diagnostic accuracy of 22-G and 25-G needles on endoscopic ultrasonography (EUS-FNA) of the solid pancreatic mass. METHODS: We established a rigorous study protocol according to Cochrane Collaboration recommendations. We systematically searched the PubMed and Embase databases to identify articles to include in the meta-analysis. Sensitivity, specificity, and corresponding 95% confidence intervals were calculated for 22-G and 25-G needles of individual studies from the contingency tables. RESULTS: Eleven prospective controlled trials included a total of 837 patients (412 with 22-G vs 425 with 25-G). Our outcomes revealed that 25-G needles (92% [95% CI, 89%-95%]) have higher sensitivity than 22-G needles (88% [95% CI, 84%-91%]) on solid pancreatic mass EUS-FNA (P = 0.046). However, there were no significant differences between the 2 groups in overall diagnostic specificity (P = 0.842). The pooled positive and negative likelihood ratio of the 22-G needle were 12.61 (95% CI, 5.65-28.14) and 0.16 (95% CI, 0.12-0.21), respectively. The pooled positive likelihood ratio was 12.61 (95% CI, 5.65-28.14), and the negative likelihood ratio was 0.16 (95% CI, 0.12-0.21) for the 22-G needle. The pooled positive likelihood ratio was 8.44 (95% CI, 3.87-18.42), and the negative likelihood ratio was 0.13 (95% CI, 0.09-0.18) for the 25-G needle. The area under the summary receiver operating characteristic curve was 0.97 for the 22-G needle and 0.96 for the 25-G needle. CONCLUSION: Compared to the study of 22-G EUS-FNA needles, our study showed that 25-G needles have superior sensitivity in the evaluation of solid pancreatic lesions by EUS-FNA.

Role of neovibsanin scaffold in preservation of spatial cognitive functions of rats with chronic epilepsy.

The effect of neovibsanin scaffold (NS) on the spatial cognitive functions of rats with lobal cerebrovascular hypoperfusion was investigated. Rats were divided into long-term memory (LTM) and short-term memory (STM) groups with 15 rats in each group. The groups were subdivided into 3 groups: control group comprised of 5 rats without surgery, untreated group of 5 rats left without treatment after 2OV, and NS treatment group with 5 rats receiving 5 mg/kg daily for 12 weeks of 2VO operation. NS-treatment caused a marked decrease in the escape latency time and total distance travelled in the treatment group compared to untreated group which was evident from the working memory test. The animals of treatment group also showed significant improvement over that of untreated group in maze test performance. Furthermore, NS treatment also resulted in significant improvement in the probe memory test performance in treatment group compared to untreated group. These findings suggest that NS exhibits therapeutic effect on the spatial cognitive preservation in rats with chronic epilepsy.

The lower peripheral blood lymphocyte/monocyte ratio assessed during routine follow-up after standard first-line chemotherapy is a risk factor for predicting relapse in patients with diffuse large B-cell lymphoma.

A specific predictor during routine follow-up to ascertain risk for relapse after standard first-line chemotherapy in non-Hodgkin's lymphoma (NHL) has not been identified, although blood counts, lactate dehydrogenase (LDH) and imaging studies, such as computed tomography (CT) scans or positron emission tomography, have been recommended. Therefore, we studied the absolute lymphocyte count/absolute monocyte count ratio (ALC/AMC ratio) as a marker of poststandard first-line chemotherapy for predicting relapse in patients with diffuse large B-cell lymphoma (DLBCL). 220 consecutive DLBCL patients, originally diagnosed, treated with CHOP or R-CHOP and followed up at two institutions. ALC/AMC ratio was obtained at the time of confirmed relapse or last follow-up. Patients at the time of confirmed relapse (n = 163) had a lower ALC/AMC ratio compared with those at last follow-up (n = 57) (P < 0.001). ALC/AMC ratio at the time of confirmed relapse was a strong predictor for relapse with an area under the curve = 0.813 (P < 0.001). The sensitivity and specificity for ALC/AMC ratio at the time of confirmed relapse or at last follow-up were 68.1% and 87.7%, respectively, and the relative risk of relapse with an ALC/AMC ratio < 2.8 at the time of confirmed relapse or at last follow-up was 1.845 with an odds ratio of 15.247 (95% cumulative incidence: 6.473-35.916) after CHOP or R-CHOP in DLBCL. Patients with an ALC/AMC ratio (< 2.8) had a higher cumulative hazard rate of relapse compared with an ALC/AMC ratio (≥2.8) (P < 0.001). This study suggests that the lower ALC/AMC ratio can be used as a marker to assess risk of DLBCL relapse during routine follow-up after standard first-line chemotherapy.