Prevalence of carbapenem-hydrolyzing class D β-lactamase genes in Acinetobacter spp. isolates in China

In order to assess the prevalence of carbapenem-hydrolyzing class D β-lactamase genes in Acinetobacter spp. isolates in China, we conducted a polymerase chain reaction (PCR)-based surveillance of OXA-type β-lactamase gene clusters for a total of 2,880 Acinetobacter spp. isolates collected from 23 Chinese provinces. All isolates were tested for susceptibility to 12 antimicrobial agents and showed high rates of resistance to all these agents except minocycline. We also found that the vast majority of carbapenem-resistant Acinetobacter spp. were OXA-23-like-producing isolates, predominantly Acinetobacter baumannii isolates. Besides, bla OXA-58-like and bla OXA-24-like genes were detected in 32 and 11 isolates, respectively, involving many provinces throughout China. Furthermore, these two carbapenem-resistance determinants were located on transferable plasmids in most cases, indicating an emerging threat for both OXA-58-like- and OXA-24-like-producing Acinetobacter spp. isolates in China. Interestingly, a novel homologue of the bla OXA-143 gene was identified in a susceptible Acinetobacter pittii isolate. Overall, these observations suggest that the bla OXA-23-harboring A. baumannii isolates are the most frequent carbapenem-resistant Acinetobacter spp. in China, and the bla OXA-24-like and bla OXA-58-like genes have emerged as potential threats of hospital outbreaks of multidrug-resistant Acinetobacter spp.

Death-associated protein-3, DAP-3, correlates with preoperative chemotherapy effectiveness and prognosis of gastric cancer patients following perioperative chemotherapy and radical gastrectomy

Background:

DAP3 is a member of the death-associated protein (DAP) family and is characterised by proapoptotic function. It is involved in both exogenous and endogenous apoptotic pathways. In our previous studies, apoptotic level was found to be correlated with the effectiveness of preoperative chemotherapy. The effectiveness of preoperative chemotherapy was also associated with the overall effectiveness of the combined therapy and prognosis. The present study aimed to investigate the role of DAP3 in the evaluation of preoperative chemotherapy effectiveness and its ability to predict prognosis in gastric cancer.

Methods:

Quantitative PCR and immunohistochemistry staining were performed in 87 patients who received combined therapy. Knockdown of DAP3 was conducted in gastric cancer cell lines to investigate its impact on cell growth, migration, adhesion and invasion. Tolerance to chemotherapy agents was determined by assessing apoptosis and caspase-3.

Results:

Higher DAP3 expression in gastric tumours was correlated with better prognosis. Knockdown of DAP3 expression promoted cell migration and enhanced resistance to chemotherapy by inhibiting apoptosis.

Conclusion:

DAP3 is a potential molecular marker for response to preoperative chemotherapy and for predicting prognosis in gastric cancer patients treated with neoadjuvant chemotherapy and gastrectomy.

Reversible Performance of Dodecyl Tetramethyl Guanidine Solution Induced by CO2 Trigger

Dodecyl tetramethyl guanidine (DTMG) were synthesized and characterized, and its reversible performance was studied. The results showed that DTMG could form bicarbonate ionic adduct after exposed to CO2, so it could be used as CO2 switchable surfactants. By bubbling CO2 through DTMG solution or heating CO2 saturated DTMG solution, the alkali and surface active properties of solution was changed reversibly. Emulsion and foam stabilized by DTMG could be controlled between stable and unstable state by CO2. In addition, the state of DTMG solution was easy to be distinguished by naked eye through a simple indicator, phenolphthalein. Pink indicated it was inactive, and colorless indicated it was active.

Molecular cytogenetic characterization of the Aegilops biuncialis karyotype

Aegilops biuncialis can be hybridized with wheat (Triticum spp) and has been used for wheat breeding and genetic studies. The A. biuncialis karyotype (U(b) U(b) M(b) M(b)) was investigated based on three A. biuncialis accessions grown in China. Two pairs of SAT chromosomes were identified as 1U(b) and 5U(b), with a karyotype formula of 2n = 4x = 28 = 14m + 10sm + 4st. Fluorescence in situ hybridization (FISH) and C-banding approaches were used to analyze the A. biuncialis accession chromosomes at the mitotic stage. Based on the C-banding and FISH patterns, all U(b) and M(b) chromosomes could be discriminated simultaneously; the three A. biuncialis accessions exhibited similar patterns, suggesting a common origin. The U(b) genome from A. biuncialis resembled the U genome in the diploid species A. umbellulata, and it may be related to the tetraploid species containing the U genome. The M(b) genome had some differences compared to the M genome in the diploid species A. comosa, and it may be related to the tetraploid species possessing the M genome. A generalized ideogram was proposed for the A. biuncialis genome, which could be useful for standardized and accurate identification of the A. biuncialis karyotype and chromosomes.

A retrospective study of different treatments of limited-stage small-cell esophageal carcinoma and associated prognostic factor analysis

Primary, small-cell esophageal carcinoma (SCEC) is a rare but highly malignant tumor. Due to lack of randomized, controlled, prospective studies, there are currently no unified treatment modalities for SCEC. This study retrospectively analyzed the outcomes of different treatments and prognostic factors that influence overall survival in patients with limited-stage SCEC. The study included 106 patients pathologically diagnosed with limited-stage SCEC at Huai'an First People's Hospital, Nanjing Medical University (Huai'an, China), between 1998 and 2007. There were 66 males and 40 females, with a median age of 58 years (range: 45-77 years). Fourteen patients received surgery alone, 42 received surgery and postoperative chemotherapy, 11 received radiotherapy alone, and 39 received concurrent chemoradiotherapy. Combined modality treatment with and without chemotherapy yielded 5-year survival rates (5YSRs) of 27.2% and 0%, respectively. Associated median survival times were 22 months and 11 months, respectively, with a hazard ratio (HR) of 2.30 (95% confidence interval [CI]: 1.42-3.73, P = 0.001). Among patients treated with surgery plus postoperative chemotherapy or with concurrent chemoradiotherapy, the 5YSRs were 31.0% and 23.1%, respectively. Median survival times were 26 months and 18 months, with an HR of 1.25 (95% CI: 0.75-2.09, P = 0.725). Multivariate survival analysis using Cox regression model showed that chemotherapy was a positive independent prognostic factor for SCEC (HR 2.92, 95% CI: 1.25-6.80). Chemotherapy-based combined modality treatment appears to increase the long-term survival of patients with limited-stage SCEC. Similar overall survival rates results are achieved with surgery combined with chemotherapy as with concurrent chemoradiotherapy, with chemotherapy being an independent prognostic factor. Randomized, controlled, prospective studies are needed to identify optimal chemotherapy regimens for treating SCEC.

Different combinations of probiotics improve the production performance, egg quality, and immune response of layer hens

To evaluate the effects of different combinations of probiotics on performance, egg quality, and immune response of layer hens, a trial was carried out with 1,800 white feather layer hens of the Lohmann variety. The experiment was conducted by using a completely randomized design with 9 treatments, 4 replicates, and 50 hens in each replicate. Compared with the control group, group F, which added a composition of heat-inactivated Lactobacillus salivarius(CB) and Bacillus subtilis to the diets of layer hens, caused highly significant (P < 0.05) increases in egg production, daily egg yield, damaged egg ratio, combined with a significant (P < 0.05) decrease in feed conversion and damaged egg ratio. Group G, adding a combination of inactivated Lactobacillus salivarius and sodium butyrate, resulted in a significant increase (P < 0.05) in daily egg yield, feed conversion, damaged egg ratio and Haugh unit. Meanwhile, groups D and H had significantly decreased feed conversion (P < 0.05), and groups B, H, and I had a significantly decreased damaged egg ratio. In serum levels, no significant difference was observed except a significant decrease (P < 0.05) in total cholesterol (groups D, E, and G) and low-density lipoprotein cholesterol (group E and G) and a significant increase (P < 0.05) in total cholesterol (groups D, E, and G) compared with group A. According to the hemagglutination inhibition test, the antibody titer of antibody against the avian influenza virus was significantly (P < 0.05) higher in most treated groups such as groups B, C, E, G, and I after d 15 fed to layers with probiotics and groups B, C, D, E, F, G, and H after d 45 compared with the control group. No significant difference was observed in the antibody titer against the Newcastle disease virus at d 15, but significantly (P < 0.05) higher at d 45 in groups F and G. These results demonstrate that several combinations of probiotics used in this experiment have a positive impact on the performance, egg quality, and immune response of layer hens, and the following work will continue to focus on these groups.

Attributable causes of cancer in China

BACKGROUND

Most cancers are due to modifiable lifestyle and environmental risk factors, and are potentially preventable. No studies have provided a systematic quantitative assessment of the burden of cancer mortality and incidence attributable to known risk factors in China.

METHODS

We calculated the proportions of cancer deaths and new cases attributable to known risk factors in China, based on the prevalence of exposure around 1990 and national data on cancer mortality and incidence for the year 2005.

RESULTS

Chronic infection is the main risk factor for cancer in China, accounting for 29.4% of cancer deaths (31.7% in men and 25.3% in women), followed by tobacco smoking (22.6% with 32.7% in men and 5.0% in women), low fruit intake (13.0%), alcohol drinking (4.4%), low vegetable intake (3.6%) and occupational exposures (2.7%). The remaining factors, including environmental agents, physical inactivity, the use of exogenous hormones and reproductive factors are each responsible for <1.0%.

CONCLUSIONS

Modifiable risk factors explain nearly 60% of cancer deaths in China, with a predominant role of chronic infection and tobacco smoking. Our findings could provide a basis for cancer prevention and control programs aimed at reducing cancer risk in other developing countries.

Effect of autoimmune diseases on mortality and survival in subsequent digestive tract cancers

BACKGROUND

Patients with some autoimmune diseases (AIDs) are at increased risk of cancer, possibly a result of an underlying dysregulation of the immune system, medication, treatment or, probably, surveillance bias. Data on cancer mortality and survival in patients previously diagnosed with AIDs would provide novel information on these comorbidities and their clinical implications.

PATIENTS AND METHODS

Standardized mortality ratios (SMRs) and hazard ratios (HRs) were calculated for subsequent deaths from seven digestive tract cancers between 1964 and 2008 in patients hospitalized for any of 33 AIDs.

RESULTS

There were 33 increased SMRs for specific cancers after a defined AID; similarly, 21 HRs were increased. Both the SMR and HR were increased after 10 autoimmune disorders, including pernicious anemia, systemic lupus erythematosus and psoriasis. Increased SMRs and unchanged HRs were noted for 23 cancers. Myasthenia gravis was associated with SMRs for five cancers but no increases in HRs. For nine cancers, including esophageal cancer after ulcerative colitis and rheumatoid arthritis, the SMR was unchanged but the HR increased.

CONCLUSIONS

The increases in SMRs provide evidence that cancer risks were truly increased and largely unaffected by surveillance bias. The prognostic survival data should contribute to clinical evaluation and therapeutic planning.

Development of a fluorescent-intercalating-dye-based reverse transcription loop-mediated isothermal amplification assay for rapid detection of seasonal Japanese B encephalitis outbreaks in pigs

The standardization and validation of a one-step, single-tube, accelerated fluorescent-intercalating-dye-based reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay targeting the NS3 gene of Japanese B encephalitis virus (JEV) is described for rapid, simple, and high-throughput detection of JEV. The amplification can be completed in 35 min under isothermal conditions at 63°C by employing a set of six primers targeting the NS3 gene of JEV. The RT-LAMP assay described demonstrated high sensitivity for detecting JEV, with a detection limit in swine samples of 8.13 PFU/ml. The specificity of the selected primer sets was established by cross-reactivity studies with pathogens that exhibit similar clinical signs and testing of samples from healthy animals. The clinical applicability of the RT-LAMP assay was validated using either spiked samples or samples from seasonal outbreaks. The comparative evaluation of the RT-LAMP assay revealed 79.59 % concordance with conventional RT-PCR targeting the E gene of JEV. The RT-LAMP assay reported here is a valuable tool for rapid real-time and high-throughput seasonal infection surveillance and quarantine after outbreak through blood sampling by using ordinary real-time PCR thermocyclers without purchasing an expensive Loopamp real-time turbidimeter.

Family history and risk of hospital treatment for varicose veins in Sweden

Background

Family history has been suggested as a risk factor for varicose veins, but recall bias may inflate the familial risks. The aim of this nationwide study was to determine familial risks for hospital treatment for varicose veins.

Methods

Data from the Swedish Multi-Generation Register of people aged 0-76 years were linked to Hospital Discharge Register data for 1964–2008. Standardized incidence ratios (SIRs) were calculated for individuals whose relatives were treated in hospital for varicose veins and compared with those whose relatives were not. Only main diagnoses of varicose veins were considered.

Results

A total of 39 396 people had hospital treatment for varicose veins. The familial SIR among offspring with one affected parent was 2·39 (95 per cent confidence interval 2·32 to 2·46). The SIR for those with one affected sibling was 2·86 (2·76 to 2·97). SIRs were increased in both men and women. The SIR for individuals with two or more affected siblings or with two affected parents was 5·88 (5·28 to 6·53) and 5·52 (4·77 to 6·36) respectively. The SIR for the wives of men treated for varicose veins was 1·69 (1·59 to 1·80); that for the husbands of women treated for varicose veins was 1·68 (1·58 to 1·79).

Conclusion

Using the Swedish Hospital Discharge Register, and thereby eliminating recall bias, family history of hospital treatment for varicose veins was associated with an increased risk of similar treatment among relatives. The increased spousal risk suggests a contribution from non-genetic factors.

Clinical factors associated with sodium removal in peritoneal dialysis patients

A cross-sectional study was conducted in 156 clinically-stable peritoneal dialysis patients to identify the factors associated with sodium removal. Serum biochemistry, peritoneal function (modified peritoneal equilibration test [PET]) and the adequacy of dialysis were analysed in relation to sodium removal using multivariate linear regression. Factors significantly affecting peritoneal sodium removal included infusion volume and ultrafiltration volume per 24 h, sodium dip in the first hour of PET and sodium difference between serum and fresh dialysate. Factors significantly affecting total sodium removal included ultrafiltration and urine volume per 24 h, sodium dip in the first hour of PET and sodium difference between serum and fresh dialysate. With traditional dialysate, adequate fluid removal is required to ensure sufficient sodium removal, but a low-sodium dialysate may prevent sodium retention. Sodium removal should be included in evaluation of the adequacy of dialysis.

Subsequent cancers in patients diagnosed with cancer of unknown primary (CUP): etiological insights?

BACKGROUND

Patterns of subsequent malignancies in patients with cancer of unknown primary (CUP) may provide etiological insight into the primary tumor. The objective of the present study is to quantify risks of the subsequent cancers in CUP patients since such studies are lacking.

PATIENTS AND METHODS

A population-based cohort of CUP was identified from the Swedish Family-Cancer Database of year 2008. Standardized incidence ratios (SIRs) were calculated for developing the following malignancies in 31,357 CUP patients from 1975 to 2008.

RESULTS

A total of 755 CUP patients developed subsequent cancers, showing a significantly increased overall SIR of 1.69 (95% confidence interval 1.57-1.81). Among the most common 32 malignancies, increased SIRs were noted for 16 sites. Over 10-fold increases were observed for squamous cell carcinoma at four sites, possibly as a result of uncontrolled human papillomavirus infection due to faltering immune surveillance. The highest SIRs were observed among CUP patients diagnosed at a younger age and during the first follow-up year.

CONCLUSIONS

Swedish CUP survivors had a higher risk of developing many subsequent cancers. Different patterns of risk excess may be suggestive of possible roles for disease- and therapy-related immunosuppression, reappearance of hidden primary tumors, or genetic predisposition.

Synthesis and Characterization of Mesoporous Alumina-Zirconia as Catalyst Support for Suzuki Coupling Reaction

One pot facile synthesis of ordered mesoporous alumina-supported zirconia with high thermal stability and large pore sizes by evaporation-induced method was systematically investigated. The strategy based on a sol-gel process associated with nonionic triblock copolymers PPO-PEO-PPO as templates in ethanolic solution. Small-angle XRD, TEM, and nitrogen adsorption and desorption results showed that these composites possessed an ordered 2D hexagonal mesostructure, resisted to high temperature up to 1000 °C, and had large surface areas and narrow pore-size distributions. Loaded with palladium, the mesoporous alumina-zirconia composite exhibited high catalytic activity in Suzuki coupling of 2-bromotoluene with phenylboronic acid.

Assessment of urinary N-acetyl-β-glucosaminidase as an early marker of contrast-induced nephropathy

Early detection and timely intervention are important for improving contrast-induced nephropathy (CIN) prognosis. Whether urinary N-acetyl-β-glucosaminidase (NAG) is a useful marker for early detection of CIN was investigated in 590 patients undergoing diagnostic coronary angiography (CA) and/or therapeutic percutaneous coronary intervention (PCI) for acute coronary syndromes or stable angina, and who received low-osmolality nonionic contrast agent. Urinary NAG, osmolality and serum creatinine were measured before and 1, 2 and 6 days after contrast agent exposure. CIN occurred in 33 patients; its incidence in high-risk patients (pre-existing renal dysfunction with/without diabetes mellitus) was significantly higher than in others. In patients with CIN, urinary NAG and serum creatinine levels on days 1 and 2 were significantly higher than at baseline and compared with patients without CIN; mean levels were gradually returning to baseline by day 6. Compared with serum creatinine, urinary NAG levels peaked earlier in CIN patients and increased much more. The results suggest that, following CA and/or PCI, CIN occurs to a certain degree and that NAG may be a useful early CIN marker as it is noninvasive, simple, inexpensive and sensitive.

Oxidative stress-resistance assay for screening yeast strains overproducing heterologous proteins

Many natural proteins have been developed into drugs and produced for direct application. Identifying improved hosts to achieve high-level heterologous protein production is a challenge in the study of heterologous protein expression in recombinant yeast. In this study, a novel high-throughput assay to screen such overproducing Saccharomyces cerevisiae strains was systematically developed. The protocol designed was based on screening host strain derivatives with increased superoxide dismutase dependent resistance to oxidative stress. Yeast cells transformed with recombinant plasmid carrying SOD1 gene as a reporter responded exquisitely to oxidative stress induced by elevated concentrations of paraquat. Improved yeast strains resulting from screening clones subjected to genome shuffling through selective pressure argue for a more effective screening system compared with traditonal selection. Moreover, this approach can be employed in general biochemical analysis without utilization of flow cytometry or well plate reader. Therefore, it is expected that the high-throughput assay would make superior strains producing heterologous proteins.