FTIR determination of the degree of molar substitution for hydroxypropyl chitosan.

We developed and validated a novel Fourier transform infrared (FTIR) method to determine the degree of molar substitution (MS) for hydroxypropyl chitosan (HPCS) using nuclear magnetic resonance (1H NMR) as a reference, and investigated the factors influencing the MS assay. Through extensive screening of integration methods for candidate bands in the FTIR spectrum of HPCS using 20 HPCS samples with degrees of acetylation (DA) ranging from 0.003 to 0.139, we found that when using band area at 2970 cm-1 as a probe integral, the MS values obtained via the 1H NMR method exhibited linear correlations (R2 > 0.98) with at least 16 integral ratios derived from their FTIR spectra. The optimal reference bands with high reliability are located at 3440 cm-1 and 1415 cm-1, with R2 exceeding 0.99 and a MS range of 0.17-1.92. The band at 2875 cm-1 is less affected by the trace moisture present in HPCS samples than the others. The results of the method validation demonstrated a mean recovery of 98.9 ± 2.8 % and an RSD below 10 %, suggesting a simple, robust, and highly accurate and precise method. This method could be extendable for the determination of the MS of insoluble HPCS derivatives and other hydroxypropylated polysaccharides.

Effect of telephone-based health education intervention models on cervical cancer screening compliance: A protocol for systematic review and meta-analysis.

BACKGROUND: Screening is an effective strategy for preventing and controlling the cervical cancer. Unfortunately, women are often less likely to adhere to cervical cancer screening procedures. Related research shows that the telephone-based health education model can improve the compliance of screening. At present, however, this practice is lack of persuasion. Therefore, this study makes a systematic meta-analysis on whether the telephone-based health education model can improve the compliance of screening by women. METHODS: Retrievals will be made on PubMed, Web of Science, the Cochrane Library, EMBASE, and some clinical trial registration websites, and information on related randomized controlled trials (RCTs) will collected. After 2 researchers independently screen the literatures, they will extract the data and evaluate the bias risk contained in the collected studies, before meta-analysis is carried out with RevMan 5.3 software. RESULTS: The available evidence will be systematically reviewed in terms of compliance with cervical cancer screening. CONCLUSION: The findings of this study will produce comprehensive evidence to identify whether the telephone-based health education model can improve women's compliance with cervical cancer screening.

Superhydrophilic and Highly Transparent TiO2 Films Prepared by Dip Coating for Photocatalytic Degradation of Methylene Blue.

Nanocrystalline TiO2 films were prepared on slide glass by sol-gel and dip-coating methods, and the samples were then annealed at 200 °C, 250 °C, 300 °C, 350 °C, 400 °C, 450 °C and 500 °C for 2 h. The samples' crystal structures, morphology, water contact angle, transmission spectra, and photocatalytic performance with respect to the degradation of methylene blue (MB) under UV light irradiation were characterized by X-ray diffraction spectroscopy, scanning electron microscopy, contact angle measurement, and UV-vis spectrophotometry. The results obtained indicate that all of the films were highly transparent to the visible spectrum, but with an increase in the annealing temperature, the optical band-gap and the water contact angle both reduced. Samples annealed at 450 °C and 500 °C exhibited superhydrophilic properties, with the hydrophilicity of the films remaining stable for at least 6 months without UV light irradiation. Among all the samples, the one annealed at 450 °C was found to have the highest maximum MB degradation rate of 71.1%.

A descriptive phenomenology study of newcomers' experience of maternity care services: Chinese women's perspectives.

BACKGROUND: Maternity health care available in Canada is based on the needs of women born in Canada and often lacks the flexibility to meet the needs of immigrant women. The purpose of this study was to explore immigrant Chinese women's experiences in accessing maternity care, the utilization of maternity health services, and the obstacles they perceived in Canada. METHODS: This descriptive phenomenology study used in-depth semi-structured interviews to examine immigrant Chinese women's experiences. Fifteen participants were recruited from the Chinese community in Toronto, Canada by using purposive sampling. The interviews were digitally recorded and transcribed verbatim into written Chinese. The transcripts were analyzed using Colaizzi's (1978) phenomenological method. RESULTS: Six themes were extracted from the interviews: (1) preference for linguistically and culturally competent healthcare providers, with obstetricians over midwives, (2) strategies to deal with the inconvenience of the Canadian healthcare system (3) multiple resources to obtain pregnancy information, (4) the merits of the Canadian healthcare system, (5) the need for culturally sensitive care, and (6) the emergence of alternative supports and the use of private services. CONCLUSIONS: The findings provide new knowledge and understanding of immigrant Chinese women's experiences in accessing maternity health services within a large metropolitan Canadian city. Participants described two unique experiences within the themes: preference for linguistically and culturally competent healthcare providers, with obstetricians over midwives, and the emergence of alternative supports and the use of private services. Few studies of immigrant maternity service access have identified these experiences which may be linked to cultural difference. Further investigation with women from different cultural backgrounds is needed to develop a comprehensive understanding of immigrant women's experiences with maternity care.

The assessment of the quality of reporting of systematic reviews/meta-analyses in diagnostic tests published by authors in China.

BACKGROUND: The quality of reporting in systematic reviews (SRs)/meta-analyses (MAs) of diagnostic tests published by authors in China has not been evaluated. The aims of present study are to evaluate the quality of reporting in diagnostic SRs/MAs using the PRISMA statement and determine the changes in the quality of reporting over time. METHODS: According to the inclusion and exclusion criteria, we searched five databases including Chinese Biomedical Literature Database, PubMed, EMBASE, the Cochrane Library, and Web of knowledge, to identify SRs/MAs on diagnostic tests. The searches were conducted on July 14, 2012 and the cut off for inclusion of the SRs/MAs was December 31(st) 2011. The PRISMA statement was used to assess the quality of reporting. Analysis was performed using Excel 2003, RevMan 5. RESULTS: A total of 312 studies were included. Fifteen diseases systems were covered. According to the PRISMA checklist, there had been serious reporting flaws in following items: structured summary (item 2, 22.4%), objectives (item 4, 18.9%), protocol and registration (item 5, 2.6%), risk of bias across studies (item 15, 26.3%), funding (item 27, 28.8%). The subgroup analysis showed that there had been some statistically significant improvement in total compliance for 9 PRISMA items after the PRISMA was released, 6 items were statistically improved regarding funded articles, 3 items were statistically improved for CSCD articles, and there was a statistically significant increase in the proportion of reviews reporting on 22 items for SCI articles (P<0.050). CONCLUSION: The numbers of diagnostic SRs/MAs is increasing annually. The quality of reporting has measurably been improved over the previous years. Unfortunately, there are still many deficiencies in the reporting including protocol and registration, search, risk of bias across studies, and funding. Future Chinese reviewers should address issues on these aspects.

Proteomic analysis of the effect of diclazuril on second-generation merozoites of Eimeria tenella.

Diclazuril has long been used as an effective benzeneacetonitrile anticoccidial for the control of Eimeria tenella that causes coccidiosis. However, the molecular mechanism underlying the anticoccidial effects of diclazuril remains elusive. In this study, a proteomic analysis of the effect of diclazuril on second-generation merozoites of E. tenella was performed. Using two-dimensional gel electrophoresis and real-time quantitative polymerase chain reaction (RT-PCR), 13 target proteins were found to be significantly affected by diclazuril treatment, with 11 of these proteins being identified as annotated proteins from E. tenella or other Apicomplexa parasites. These proteins contribute to various functions, including metabolism, protein synthesis, and host cell invasion. Using RT-PCR, we identified the potential pattern of transcriptional regulation induced by diclazuril, and we suggest some promising targets for the intervention of E. tenella infection.

Information derived from cluster ions from DNA-modified gold nanoparticles under laser desorption/ionization: analysis of coverage, structure, and single-nucleotide polymorphism.

In this study, we employed laser desorption/ionization mass spectrometry (LDI-MS) to explore the interactions between thiolated DNA (HS-DNA) and gold nanoparticles (Au NPs). Under nanosecond-pulsed laser irradiation (Nd:YAG, 355 nm), the efficiency of Au cluster ion formation from the Au NPs decreased in the presence of HS-DNA. At the optimal laser power density (2.1 × 10(4) W cm(-2)), the intensity of the Au cluster signal was sensitive to the DNA coverage and the length of the DNA strands on the Au NPs (diameter: 13 nm). Using this information, we developed a simple and specific DNA sensor that operates through analysis of the Au cluster ions formed from the fragmentation of Au NPs under LDI conditions. The coverage of the thiolated probe DNA (pDNA) on the Au NPs increased in the presence of its perfectly matched DNA (DNA(pm)). As a result, the intensity of the signal of Au cluster ions decreased upon increasing the concentration of DNA(pm). Coupling these pDNA-Au NPs with LDI-MS allowed the detection of DNA(pm) at concentrations down to the nanomolar regime. Furthermore, we applied this pDNA-Au NP probe to the detection of single-nucleotide polymorphisms (SNPs) of the Arg249Ser unit in the TP53 gene. To the best of our knowledge, this paper provides the first example of the use of LDI to analyze the coverage and structure of DNA strands on metal NPs. This simple, rapid, high-throughput detection system, based on the coupling of biofunctional Au NPs with LDI-MS, appears to hold great practicality for bioanalyses of oligonucleotides and proteins.

Pulsed-laser desorption/ionization of clusters from biofunctional gold nanoparticles: implications for protein detections.

In this paper, we describe a pulsed-laser desorption/ionization mass spectrometry (LDI-MS) approach for the detection of proteins with femtomolar sensitivity through the analysis of gold (Au) clusters desorbed from aptamer-modified gold nanoparticles (Apt-AuNPs) on a nitrocellulose membrane (NCM). After the target protein (thrombin) was selectively captured by the surface-bound 29-mer thrombin-binding aptamer (TBA(29)), the thrombin/TBA(29)-AuNP complexes were concentrated and deposited onto the NCM to form a highly efficient background-free surface-assisted LDI substrate. Under pulsed laser irradiation (355 nm), the binding of thrombin decreased the desorption and/or ionization efficiencies of the Au atoms from the AuNP surfaces. The resulting decreases in the intensities of the signals for Au clusters in the mass spectra provided a highly amplified target-labeling indicator for the targeted protein. Under optimized conditions, this probe was highly sensitive (limit of detection: ca. 50 fM) and selective (by at least 1000-fold over other proteins) toward thrombin; it also improved reproducibility (<5%) of ion production by presenting a more-homogeneous substrate surface, thereby enabling LDI-based measurements for the accurate and precise quantification of thrombin in human serum. This novel LDI-MS approach allows high-speed analyses of low-abundance thrombin with ultrahigh sensitivity; decorating the AuNP surfaces with other aptamers also allowed amplification of other biological signals.

Trehalose-6-phosphate synthase 1 from Metarhizium anisopliae: clone, expression and properties of the recombinant.

Trehalose, an important component in fungal spores, is a disaccharide which protects against several environmental stresses, such as heat, desiccation, salt. Trehalose-6-phosphate synthase 1 (TPS1) is a subunit of trehalose synthase complex in fungi; it plays a key role in the biosynthesis of trehalose. In this study, a full-length cDNA from Metarhizium anisopliae encoding TPS1 (designated as MaTPS1) was isolated. The MaTPS1 cDNA is composed of 1836 nucleotides encoding a protein of 517 amino acids with a molecular mass of 58 kDa. The amino acid sequence has a relatively high homology with the TPS1s in several other filamentous fungi. Southern blot analysis showed that MaTPS1 gene occurs as a single copy in the M. anisopliae genome. And MaTPS1 was cloned into Pichia pastoris KM71 and secretively expressed with a histamine tag to facilitate a rapid purification of recombinant MaTPS1 (designated reTPS1). The properties of reTPS1 were examined. The K(m) value of reTPS1 for UDP-glucose and glucose-6-phosphate was 9.6 mM and 3.9 mM, respectively, and the optimal pH and temperature were about 6.5 and 40 degrees C. The enzyme was highly specific to glucose-6-phosphate for glucosyl acceptor, and its activity decreased rapidly as the concentrations of phosphate increased. The expression system will provide sufficient amounts of reTPS1 for future structural characterization of the protein and use for further investigation of MaTPS1's function.

Challenges and opportunities in processing muscle sympathetic nerve activity with wavelet denoising techniques: detecting single action potentials in multiunit sympathetic nerve recordings in humans.

An important issue in analysis of muscle sympathetic nerve activity (MSNA), particularly those measures made in humans, is the problem that background noise of varying levels from recording to recording may interfere with accurate assessment of neural discharge patterns and overall activity. In this study, the utility of wavelet denoising approaches for processing MSNA signals was examined with emphasis on 1) determining whether this approach could improve the signal-to-noise (SNR) in the integrated neurogram, and 2) detecting intra-burst single action potential spikes. The utility of wavelet denoising was examined in simulated data and in original human data with three recordings of varying SNR (low, moderate and high) obtained from two healthy individuals. Only in the high SNR signal was the noise removed without concurrent loss of signal. Using a threshold-detecting algorithm individual depolarization spikes were detected in denoised recordings of high original SNR (>3:1) from four individuals and the interspike interval characteristics of these were quantified on a burst-by-burst basis. Compared with baseline (15+/-1 spikes/burst) a reflexive increase in spike count (29+/-4 spikes/burst) was observed during a held maximal inspiration (P<0.01) with concurrent reductions in inter-spike interval (P<0.01). The findings indicate that within multiunit bursts of sympathetic neural activity in the band-pass filtered neural signal, there are particular frequency components that appear to be shared between the signal and noise. This may limit the utility of wavelet denoising to enhance detection of neural bursts in the integrated neurogram of MSNA. However, opportunities exist with this approach to detect variations in action potential contributions within each burst of MSNA. This latter observation suggests that this denoising approach provides a new probe to explore MSNA discharge patterns.