Serotype, antibiotic susceptibility and whole-genome characterization of Streptococcus pneumoniae in all age groups living in Southwest China during 2018-2022.

Background: Streptococcus pneumoniae is a common pathogen that colonizes the human upper respiratory tract, causing high morbidity and mortality worldwide. This study aimed to investigate the prevalence status of S. pneumoniae isolated from patients of all ages in Southwest China, including serotype, antibiotic susceptibility and other molecular characteristics, to provide a basis for clinical antibiotic usage and vaccine development. Methods: This study was conducted from January 2018 to March 2022 at West China Hospital, West China Second University Hospital, First People's Hospital of Longquanyi District (West China Longquan Hospital), Meishan Women and Children's Hospital (Alliance Hospital of West China Second University Hospital) and Chengdu Jinjiang Hospital for Women and Children Health. Demographic and clinical characteristics of 263 pneumococcal disease (PD) all-age patients were collected and analyzed. The serotypes, sequence types (STs), and antibiotic resistance of the strains were determined by next-generation sequencing, sequence analysis and the microdilution broth method. Results: The most common pneumococcal serotypes were 19F (17.87%), 19A (11.41%), 3 (8.75%), 23F (6.46%) and 6A (5.70%). Coverage rates for PCV10, PCV13, PCV15, PCV20 and PCV24 were 36.12, 61.98, 61.98, 63.12 and 64.26%, respectively. Prevalent STs were ST271 (12.55%), ST320 (11.79%), ST90 (4.18%), ST876 (4.18%) and ST11972 (3.42%). Penicillin-resistant S. pneumoniae (PRSP) accounted for 82.35 and 1.22% of meningitis and nonmeningitis PD cases, respectively. Resistance genes msrD (32.7%), mefA (32.7%), ermB (95.8%), tetM (97.3%) and catTC (7.6%) were found among 263 isolates. Most isolates showed high resistance to erythromycin (96.96%) and tetracycline (79.85%), with more than half being resistant to SXT (58.94%). A few isolates were resistant to AMX (9.89%), CTX (11.03%), MEN (9.13%), OFX (1.14%), LVX (1.14%) and MXF (0.38%). All isolates were susceptible to vancomycin and linezolid. Conclusion: Our study provides reliable information, including the prevalence, molecular characterization and antimicrobial resistance of S. pneumoniae isolates causing pneumococcal diseases in Southwest China. The findings contribute to informed and clinical policy decisions for prevention and treatment.

Low-Background Signal-On Homogeneous Electrochemiluminescence Biosensor for Hepatitis B Virus Detection Based on the Regulation of the Length of DNA Modified on the Nanoparticles by CRISPR/Cas12a and Hybridization Chain Reaction.

In this work, combined with the high amplification efficiency of hybridization chain reaction (HCR), high specificity of the CRISPR/Cas12a system, and convenience of the homogeneous electrochemiluminescence (ECL) assay based on the regulation of negative charge on the reporting probes, a sensitive ECL biosensor for hepatitis B virus DNA (chosen as a model target) had been developed. The initiator chain trigger DNA that can induce HCR amplification is modified on the surface of ruthenium bipyridine-doped silica nanoparticles (Ru@SiO2 NPs) first, and large amounts of negative charges modified on the particles were achieved through the HCR amplification reaction. The efficiency of the nanoparticles reaching the negatively charged working electrode can be regulated and realize the change of the ECL signal. In addition, long DNA on the surface of the luminescent body may prevent the coreactant from entering the pore to react with ruthenium bipyridine. These factors combine to produce a low-background system. The presence of the target can activate the CRISPR/Cas12a system and make trigger DNA disappear from the nanoparticle surface, and strong ECL can be detected. The sensor does not require a complex electrode modification; therefore, it has better reproducibility. Additionally, due to dual signal amplification, the sensor has a high sensitivity. In the range of 10 fM to 10 nM, the ECL intensity exhibits a strong linear relationship with the logarithm of the target concentration, and the detection limit is 7.41 fM. This sensor has shown high accuracy in detecting clinical samples, which holds significant potential for application in clinical testing.

Variation of Bone Turnover Markers in Childhood and Adolescence.

Objectives: To determine the bone metabolic marker changes from childhood to adolescence and to provide reference values for monitoring bone development in children in Southwest China. Methods: We surveyed 703 participants attending physical examinations from April 2019 and August 2021. Twenty-eight participants were excluded for lack of laboratory tests, and 14 people were excluded for diseases that might affect bone metabolism. A total of 661 children were selected for the study. According to the main developmental periods, the children were divided into preschool, preadolescence, and adolescence groups. Serum bone turnover markers including ß-isomerized C-terminal telopeptide of type I collagen (ß-CTx), N-terminal midfragment of osteocalcin (N-MID), and procollagen type 1 N-propeptide (P1NP) as well as growth and development indices such as serum calcium (Ca), phosphorus (Pi), alkaline phosphatase (ALP), and vitamin D were measured. The changes in bone metabolism-related markers and the correlations between the indices were analyzed. Results: During the development in boys, the levels of ß-CTx and N-MID increased with age from preschool to adolescence, while the levels of P1NP decreased and then increased. In girls, the levels of ß-CTx and N-MID plateaued in early adolescence and showed little change in subsequent adolescence, while the levels of P1NP exhibited a downward trend. The correlations between bone metabolism markers and vitamin D were not significant. Conclusions: The levels of bone metabolism markers differed between boys and girls. Reference intervals can be used as essential tools to examine the levels of bone metabolism markers reasonably.

The kidney antifibrotic effects of 5,7,3',4',5'-pentamethoxyflavone from Bauhinia championii in streptozotocin-induced diabetic rats: in vivo and in vitro experiments.

CONTEXT: The antidiabetic effects of flavonoids have been reported, but it is still unclear whether 5,7,3',4',5'-pentamethoxyflavone, isolated from Bauhinia championii Benth. (Fabaceae), also exhibits such properties. OBJECTIVE: To isolate 5,7,3',4',5'-pentamethoxyflavone from B. championii using high-speed countercurrent chromatography and examine its potential in treating diabetic nephropathy. MATERIALS AND METHODS: The phytochemical constituents from the stems of B. championii were separated and purified with high-speed countercurrent chromatography; 5,7,3',4',5'-pentamethoxyflavone (PMF) was identified by mass spectrum, 1H-NMR, and 13C-NMR. After exposing mesangial cells to 30 mM glucose and either 5 µM or 10 µM PMF for 6 h, the levels of fibronectin (FN) and p-Smad2/3 were analyzed using Western blotting. Male Sprague-Dawley rats were injected intraperitoneally with 55 mg/kg streptozotocin to induce diabetes and then were randomized into three groups (n = 10): vehicle administration, low-dose (5 mg/kg) PMF, and high-dose (25 mg/kg) PMF by intragastric gavage for 3 months. A healthy group was included as the control. RESULTS: Compared to the diabetic group, low-dose and high-dose PMF treatment decreased the phosphorylation of Smad2/3 by 0.54- and 0.52-fold, and the accumulation of FN decreased by 0.82- and 0.77-fold in vitro; the phosphorylation of Smad2/3 was decreased by 0.39- and 0.37-fold, and the accumulation of FN decreased by 0.47- and 0.40-fold in vivo, respectively. Furthermore, PMF alleviated the glomerular basement membrane thickness and foot process fusion. CONCLUSION: The findings suggest for the first time that PMF may be a promising treatment option for diabetic kidney fibrosis, which warrants additional clinical investigation.

Dual-target nucleic acid sequences responsive electrochemiluminescence biosensor using single type carbon dots as probe for SARS-CoV-2 detection based on series catalytic hairpin assembly amplification.

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) is rampant all over the world, and rapid and effective virus detection is the best auxiliary to curb the spread of the epidemic. A diagnosis can only be made if two or more different nucleic acid sequences are confirmed at the same time, and in most of traditional detection technologies, these target sequences have been detected separately. In this work, an electrochemiluminescent (ECL) biosensor employing a single ECL probe as signal output and responding to dual-target simultaneously is proposed for the first time. Taking the two sequences located in ORF 1ab region and N region of SARS-CoV-2 gene sequence as the model target and nitrogen doped carbon quantum dots (CDs) as ECL beacon, supplemented with catalytic hairpin assembly (CHA) reaction for signal amplification, the presented strategy has been successfully applied to the rapid detection of SARS-CoV-2. The developed SARS-CoV-2 biosensor based on the series CHA systems can realize the quantitative determination of SARS-CoV-2 in the range of 50 fM to 200 pM within 40 min. Moreover, the clinical validity of this method has been verified by the high consistency between the detection results of using this method and those using RT-qPCR for seven clinical pharyngeal swab samples.

Kirenol alleviates diabetic nephropathy via regulating TGF-ß/Smads and the NF-κB signal pathway.

CONTEXT: Kirenol possesses anti-inflammatory, antifibrotic and anti-arthritic effects. However, its reno-protective effects against diabetic nephropathy (DN) have not been evaluated. OBJECTIVE: This study explores the reno-protective effects of kirenol against DN and clarifies the potential mechanisms. MATERIALS AND METHODS: The mesangial cells were treated with 20 µM kirenol and 10 ng/mL human recombinant TGF-ß1 or 30 mM glucose for 24 h. Then the cells were harvested to assay the expression of the target genes or proteins. Thirty C57BL/6J male mice were given high-fat diet with streptozotocin injection to induce diabetes and then were randomized into three groups (n = 10): vehicle administration (DM group), 2 mg/kg kirenol (DM + kirenol group) and 200 mg/kg metformin (Met group) for 3 months, orally. A healthy group (Con, n = 10) was included as the control. RESULTS: Compared to the DM group, kirenol treatment decreased the phosphorylation of Smad2/3 and NF-κB (0.64- and 0.43-fold) as well as the accumulation of FN and Col IV (0.58- and 0.35-fold); moreover, the expression of IκBα was restored to normal level by kirenol treatment both in vivo and in vitro. After kirenol treatment, IL-6 expression was decreased 0.35- and 0.57-fold, and TNF-α expression was decreased 0.34- and 0.46-fold, in vitro and in vivo, respectively. Furthermore, kirenol alleviated the glomerular basement membrane thickness and foot process fusion. DISCUSSION AND CONCLUSIONS: Kirenol could alleviate DN by downregulating the TGF-ß/Smads and the NF-κB signal pathway. Our study provides a potential mechanism for the treatment of DN with kirenol.

Broad application prospects of bone turnover markers in pediatrics.

BACKGROUND: Bone turnover markers (BTMs) have been studied for application in clinical medicine. However, BTMs in children are challenging, and few studies explore these BTMs in children. The application of BTMs is complicated mainly due to pre-analytical factors, variable reference intervals of age- and sex-related BTMs for adolescents and children in different regions and laboratories. Therefore, laboratory testing of BTMs is critical for understanding pediatric bone development and metabolism, which provides additional information about bone development and diseases. METHODS: Literature search was conducted using the MeSH term "child" combined with the terms that bone turnover markers such as "osteocalcin," "Procollagen type I N-terminal propeptide," "procollagen type I C-terminal propeptide," "osteocalcin," "N-terminal cross-linked telopeptide," and "C-terminal cross-linked telopeptide," Several databases including Web of Science, Google Scholar, and PubMed were searched to obtain the relevant studies. RESULTS: BTMs represent the combined effects of skeletal development, growth, and remodeling in children, which can be used in clinical pediatrics to assist in the diagnosis and prognosis of bone metabolic disorders. CONCLUSION: BTMs are clearly helpful for diagnosis and monitoring of bone growth and development as well as bone metabolic disorders.

Molecular Characterization Based on Whole-Genome Sequencing of Streptococcus pneumoniae in Children Living in Southwest China During 2017-2019.

Background: Streptococcus pneumoniae is an important pathogen causing high morbidity and high mortality in children and undergoes frequent recombination for capsule switching to neutralize the 13-valent pneumococcal conjugate vaccine (PCV13). This study aimed to investigate the prevalence, and molecular characteristics including serotypes and antibiotic susceptibility of S. pneumoniae isolated from children living in Southwest China from 2017 to 2019 to facilitate the selection of effective vaccine formulations and appropriate antibiotic treatment regimens. Methods: This study was conducted at West China Second University Hospital (Chengdu, Sichuan Province, China), Zunyi Medical University Third Affiliated Hospital/First People's Hospital of Zunyi (Zunyi, Guizhou Province, China) and Chengdu Jinjiang District Maternal and Child Healthcare Hospital (Chengdu, Sichuan Province, China). Demographic and clinical characteristics of children infected with S. pneumoniae were collected and analysed. Next-generation sequencing and sequence analysis were used to determine the serotypes, sequence types, antibiotic resistance and potential protein vaccine target genes of the pneumococcal isolates. The coverage rate provided by PCV13 was estimated by calculating the percentage of the specific serotypes that were specifically the PCV13-included serotypes. Antimicrobial susceptibility was determined by the microdilution broth method. Results: The most prevalent pneumococcal serotypes were 19F (25.8%), 19A (14.1%), 6B (12.5%), 6A (9.4%) and 14 (7.8%). The predominant STs were ST271 (23.3%), ST320 (15.5%) and ST90 (8.6%), dominated by the clonal complex Taiwan19F-14 (39.1%). The coverage rate of PCV13 was 77.3% in all the isolates, with relatively higher values in invasive isolates (86.4%). Over the decade, the rates of resistance to penicillin, amoxicillin and cefotaxime were 5.6%, 5.3% and 5.1%, respectively, with significantly higher values in invasive isolates (22.4%, 14.9% and 11.9%). Almost all the isolates were resistant to erythromycin (99.1%) and clindamycin (95.9%). All isolates carried virulence-related genes, including ply, psaA, piaA, piuA, phtE, nanA, pepO, danJ, pvaA, clpP, pcsB, stkP, potD, and strH. The carriage of virulence and resistance genes varied among serotypes and clades, with serotype 19F/ST271 showing higher resistance to antibiotics and being more likely to carry pilus genes and other virulence genes. Conclusion: These data provide valuable information for the understanding of pneumococcal pathogenesis, antimicrobial resistance and the development of protein-based vaccines against pneumococcal infection.

Haemonchus contortus Transthyretin-Like Protein TTR-31 Plays Roles in Post-Embryonic Larval Development and Potentially Apoptosis of Germ Cells.

Transthyretin (TTR)-like proteins play multi-function roles in nematode and are important component of excretory/secretory product in Haemonchus contortus. In this study, we functionally characterised a secretory transthyretin-like protein in the barber's pole worm H. contortus. A full-length of transthyretin-like protein-coding gene (Hc-ttr-31) was identified in this parasitic nematode, representing a counterpart of Ce-ttr-31 in Caenorhabditis elegans. High transcriptional levels of Hc-ttr-31 were detected in the egg and early larval stages of H. contortus, with the lowest level measured in the adult stage, indicating a decreased transcriptional pattern of this gene during nematode development. Localisation analysis indicated a secretion of TTR-31 from the intestine to the gonad, suggesting additional roles of Hc-ttr-31 in nematode reproduction. Expression of Hc-ttr-31 and Ce-ttr-31 in C. elegans did not show marked influence on the nematode development and reproduction, whereas Hc-ttr-31 RNA interference-mediated gene knockdown of Ce-ttr-31 shortened the lifespan, decreased the brood size, slowed the pumping rate and inhibited the growth of treated worms. Particularly, gene knockdown of Hc-ttr-31 in C. elegans was linked to activated apoptosis signalling pathway, increased general reactive oxygen species (ROS) level, apoptotic germ cells and facultative vivipary phenotype, as well as suppressed germ cell removal signalling pathways. Taken together, Hc-ttr-31 appears to play roles in regulating post-embryonic larval development, and potentially in protecting gonad from oxidative stress and mediating engulfment of apoptotic germ cells. A better knowledge of these aspects should contribute to a better understanding of the developmental biology of H. contortus and a discovery of potential targets against this and related parasitic worms.

Highly Sensitive Homogeneous Electrochemiluminescence Biosensor for Alkaline Phosphatase Detection Based on Click Chemistry-Triggered Branched Hybridization Chain Reaction.

Alkaline phosphatase (ALP) has been used as a diagnostic index of clinical diseases since its expression level is closely related to many pathological processes. In this work, a highly sensitive electrochemiluminescence (ECL) method for the determination of ALP based on a click chemistry-induced branched hybridization chain reaction (BHCR) for signal amplification and ultrafiltration technology for the separation of homogeneous amplification products is introduced. ALP can release copper ions from a Cu2+/PPi complex by hydrolyzing pyrophosphoric acid, which initiates click chemistry in the system. A BHCR amplification is triggered afterward by the long single-stranded DNA (ssDNA) generated by click chemistry, resulting in a three-dimensional double-stranded DNA (dsDNA) with a large molecular weight. Based on the characteristic that Ru(phen)32+ can stably insert into the groove of dsDNA, a large amount of Ru(phen)32+ is retained together with the amplified product after ultrafiltration, and therefore a significantly enhanced ECL signal can be obtained. The test results show that this method can be used for the quantitative determination of ALP ranging from 0.002 to 50 U/L, with a detection limit of 0.7 mU/L. This method has also been confirmed to have good selectivity and anti-interference, and the results of the analysis of the ALP content in the diluted serum samples are satisfactory, showing great application potential in clinical diagnosis.

Acyl-CoA oxidase ACOX-1 interacts with a peroxin PEX-5 to play roles in larval development of Haemonchus contortus.

Hypobiosis (facultative developmental arrest) is the most important life-cycle adaptation ensuring survival of parasitic nematodes under adverse conditions. Little is known about such survival mechanisms, although ascarosides (ascarylose with fatty acid-derived side chains) have been reported to mediate the formation of dauer larvae in the free-living nematode Caenorhabditis elegans. Here, we investigated the role of a key gene acox-1, in the larval development of Haemonchus contortus, one of the most important parasitic nematodes that employ hypobiosis as a routine survival mechanism. In this parasite, acox-1 encodes three proteins (ACOXs) that all show a fatty acid oxidation activity in vitro and in vivo, and interact with a peroxin PEX-5 in peroxisomes. In particular, a peroxisomal targeting signal type1 (PTS1) sequence is required for ACOX-1 to be recognised by PEX-5. Analyses on developmental transcription and tissue expression show that acox-1 is predominantly expressed in the intestine and hypodermis of H. contortus, particularly in the early larval stages in the environment and the arrested fourth larval stage within host animals. Knockdown of acox-1 and pex-5 in parasitic H. contortus shows that these genes play essential roles in the post-embryonic larval development and likely in the facultative arrest of this species. A comprehensive understanding of these genes and the associated ß-oxidation cycle of fatty acids should provide novel insights into the developmental regulation of parasitic nematodes, and into the discovery of novel interventions for species of socioeconomic importance.

Homogeneous electrochemical biosensor for microRNA based on enzyme-driven cascaded signal amplification strategy.

Infectious diseases are a long-standing and severe global public health problem. The rapid diagnosis of infectious diseases is an urgent need to solve this problem. MicroRNA (miRNA) plays an important role in the intervention of some infectious diseases and is expected to become a potential biomarker for the diagnosis and prognosis of infectious diseases. It is of great significance to develop rapid and sensitive methods for detecting miRNA for effective control of infectious diseases. In this study, a simple and highly sensitive homogeneous electrochemical method for microRNAs using enzyme-driven cascaded signal amplification has been developed. In the presence of target miRNA, the reaction system produced plenty of MB-labeled single-nucleotide fragments (MB-MF) containing a few negative charges, which can diffuse to the negative surface of the ITO electrode easily, so an obvious electrochemical signal enhancement was obtained. Without the target, MB-HP contains a relatively large amount of negative charges due to the phosphates on the DNA chain, which cannot be digested by the enzyme and cannot diffuse freely to the negatively charged ITO electrode, so only a small signal was detected. The enhanced electrochemical response has a linear relationship with the logarithm of miRNA concentration in the range of 10 fM to 10 nM and the limit of detection as low as 3.0 fM. Furthermore, the proposed strategy showed the capability of discriminating single-base mismatch and performed eligibly in the analysis of miRNA in cell lysates, exhibiting great potential for disease diagnosis and biomedical research. Graphical abstract.

Development of SYBR Green real-time PCR for diagnosis of fasciolosis in sheep.

Fasciolosis is commonly diagnosed by microscopic detection of egg following sedimentation. However, this technique is time-consuming when a large number of samples must be processed and requires sufficient experience. Quantitative real-time PCR based on the detection of liver fluke ribosomal DNA in feces has been introduced, which is more accurate and liable to reflect the presence of flukes in hosts. This study aimed to develop an efficient molecular detection method in laboratory diagnosis. A cross-sectional study of 250 sheep was performed to detect Fasciola hepatica infections using gold standard microscopic detection, conventional PCR and real-time PCR. Both conventional and real-time PCRs targeted the internal transcribed spacer 2 (ITS-2). A composite reference standard(CRS) was used to analyze the sensitivity and specificity of three methods. Furthermore, the minimal amount of plasmid DNA detected by the real-time PCR was 1.67 pg plasmid DNA (equivalent to 1.1 × 106 copies). In conclusion, a highly sensitive and specific method for fasciolosis in sheep was developed.

A Highly Sensitive Electrochemiluminescence Biosensor for Pyrophosphatase Detection Based on Click Chemistry-Triggered Hybridization Chain Reaction in Homogeneous Solution.

The abnormal expression of pyrophosphatase (PPase) is closely related to many diseases and malignant tumors, so the detection for PPase is of great significance in clinical diagnosis, disease monitoring, and other biomedical aspects. In this study, a sensitive and specific electrochemiluminescence (ECL) biosensor combined highly specific Cu+-catalyzed azide-alkyne cycloaddition (CuAAC) with high efficiency of hybridization chain reaction (HCR) for the purpose of detecting pyrophosphatase has been designed. Highly efficient hybridization chain reaction amplification processed in homogeneous solution and the amplification products were connected to the electrode surface in one step, which solved the problem of low DNA amplification efficiency on the electrode surface because of the steric hindrance. Ru(phen)32+ was embedded into the dsDNA and functioned as ECL probes; the enhanced ECL intensity of the system had a linear relationship with the logarithm of PPase concentration in the range of 0.025-50 mU with a detection limit of 8 µU. The method was proved to be of good specificity, repeatability, and stability that could be used for screening and quantitatively determining pyrophosphatase inhibitor sodium fluoride. The practicability of this method in clinical application has been proved through the detection of serum from the clinical arthritis patients. Moreover, the method can be used to monitor PPase activity of arthritis patients before and after administration to provide reference for the effect of drug treatment.

Electrochemiluminescence Biosensor for Hyaluronidase Based on the Ru(bpy)32+ Doped SiO2 Nanoparticles Embedded in the Hydrogel Fabricated by Hyaluronic Acid and Polyethylenimine.

Hyaluronidase (HAase), a specific enzyme of hyaluronic acid (HA), has been reported as a potential tumor biomarker in recent years. Hence, developing some simple, rapid, and sensitive methods for HAase assay is necessary. In this work, a simple and sensitive biosensor constructed by a reliable controlled release system and a mature electrochemiluminescence (ECL) analytical technique has been devised for the quantification of HAase with high efficiency and selectivity. Tris (2,2'-bipyridyl) ruthenium(II) chloride hexahydrate doped SiO2 nanoparticles (Ru@SiO2 NPs), as ECL signal probes, were trapped in the hydrogel fabricated by HA and polyethylenimine evenly and steadily. When HAase existed, the hydrogel was decomposed by HAase, and the Ru@SiO2 NPs escaped from the hydrogel into the supernate. The ECL signal produced from the supernate can be detected and used to characterize HAase concentration. The result showed a good linear relationship between ECL intensity, and HAase concentration ranged from 2 to 60 U/mL and the limit of detection was 2 U/mL. The developed controlled release ECL biosensor has been used for HAase quantification in urine samples with satisfactory results.

An ultrasensitive electrochemiluminescence biosensor for nuclear factor kappa B p50 based on the proximity hybridization-induced hybridization chain reaction.

Nuclear factor kappa B p50 (NF-κB p50) induces various biological processes. In this study, a highly selective and sensitive electrochemiluminescence (ECL) biosensor for the detection of NF-κB p50 has been developed, which combines the high selectivity of the proximity hybridization assay (PHA) with the high efficiency of the hybridization chain reaction (HCR).

Highly sensitive electrochemical immunosensor for golgi protein 73 based on proximity ligation assay and enzyme-powered recycling amplification.

Golgi protein 73 (GP73) is a potential hepatocellular carcinoma serum marker with better sensitivity and specificity. In this study, a highly sensitive electrochemical immunosensor which combines the highly selective proximity ligation assay (PLA) and highly efficient enzyme-powered recycling amplification has been developed for GP73 determination. PLA is triggered by affinity binding of two labelled antibody-DNA (P1-RAb and P2-MAb) to target protein, resulting in increased specificity. The formed immunocomplex hybrids with DNA2 to realize the release of methylene blue labelled mononucleotides fragment with the help of exonuclease III, which acts as the power of recycling amplification. The fragment can diffuse easily to the nafion modified indium tin oxide electrode surface and a strong electrochemical signal can be detected. Under the optimized conditions, the enhanced electrochemical intensity has a linear relationship with the concentration of GP73 in the range of 0.3 pg mL-1 to 6.0 ng mL-1 with the detection limit of 0.10 pg mL-1. The developed immunosensor has been applied to detect the GP73 in the clinical serum samples with satisfactory results.

Correlation between infection of herpes virus family and liver function parameters: a population-based cross-sectional study.

INTRODUCTION: To evaluate the relationship between seropositivity to herpes virus family and liver function parameters in children from southwest China. METHODOLOGY: A 2-year cross-sectional retrospective study of 6,396 children aged 6 months to 12 years was performed. All participants underwent physical examination and liver function tests. RESULTS: Of the children, 622 were positive for EBV, HSV, or CMV IgM, with dramatic changes in liver function parameters. Aspartate aminotransferase and alanine aminotransferase levels were negatively correlated with EBV-IgM and hepatocellular injuries in children < 3 years of age, whereas a positive correlation between lactate dehydrogenase (LDH) and EBV-IgM and hepatocellular injuries was documented in children < 1 year of age. In those < 1 year and 3-6 years of age, HSV-IgM seropositivity was positively correlated with indirect bilirubin and γ-glutamyl transferase. The percentage of children < 1 year of age with positive CMV-IgM was 72.8% (158/217), approximately five times higher than that in those 1-3 years. Sixty-three children were infected with two pathogens simultaneously. Abnormal levels of LDH were observed in 85.71% of children simultaneously infected with CMV and HSV, 77.78% for CMV and EBV, 83.33% for EBV and HSV, and irregular levels of AST were noted in 69.19% of children infected with CMV and HSV, 77.78% for CMV and EBV, and 83.33% for EBV and HSV. CONCLUSIONS: Seropositivity to herpes virus family was correlated with abnormal liver function parameters across years of age. Clinicians should aim to protect the liver function of children infected with herpes viruses.

Application of DNA Barcodes in Asian Tropical Trees--A Case Study from Xishuangbanna Nature Reserve, Southwest China.

BACKGROUND: Within a regional floristic context, DNA barcoding is more useful to manage plant diversity inventories on a large scale and develop valuable conservation strategies. However, there are no DNA barcode studies from tropical areas of China, which represents one of the biodiversity hotspots around the world. METHODOLOGY AND PRINCIPAL FINDINGS: A DNA barcoding database of an Asian tropical trees with high diversity was established at Xishuangbanna Nature Reserve, Yunnan, southwest China using rbcL and matK as standard barcodes, as well as trnH-psbA and ITS as supplementary barcodes. The performance of tree species identification success was assessed using 2,052 accessions from four plots belonging to two vegetation types in the region by three methods: Neighbor-Joining, Maximum-Likelihood and BLAST. We corrected morphological field identification errors (9.6%) for the three plots using rbcL and matK based on Neighbor-Joining tree. The best barcode region for PCR and sequencing was rbcL (97.6%, 90.8%), followed by trnH-psbA (93.6%, 85.6%), while matK and ITS obtained relative low PCR and sequencing success rates. However, ITS performed best for both species (44.6-58.1%) and genus (72.8-76.2%) identification. With trnH-psbA slightly less effective for species identification. The two standard barcode rbcL and matK gave poor results for species identification (24.7-28.5% and 31.6-35.3%). Compared with other studies from comparable tropical forests (e.g. Cameroon, the Amazon and India), the overall performance of the four barcodes for species identification was lower for the Xishuangbanna Nature Reserve, possibly because of species/genus ratios and species composition between these tropical areas. CONCLUSIONS/SIGNIFICANCE: Although the core barcodes rbcL and matK were not suitable for species identification of tropical trees from Xishuangbanna Nature Reserve, they could still help with identification at the family and genus level. Considering the relative sequence recovery and the species identification performance, we recommend the use of trnH-psbA and ITS in combination as the preferred barcodes for tropical tree species identification in China.