The impact of chemical properties of the solid-liquid-adsorbate interfaces on the entropy-enthalpy compensation involved in adsorption.

Despite extensive studies on the thermodynamic mechanism governing molecular adsorption at the solid-water interface, a comprehensive understanding of the crucial role of interface properties in mediating the entropy-enthalpy compensation during adsorption is lacking, particularly at a quantitative level. Herein, we employed two types of surface models (hydroxyapatite and graphene) along with a series of amino acids to successfully elucidate how distinct interfacial features dictate the delicate balance between entropy and enthalpy variations. The adsorption of all amino acids on the hydroxyapatite surface is an enthalpy-dominated process, where the water-induced enthalpic component of the free energy and the surface-adsorbate electrostatic interaction term alternatively act as the driving force for adsorption in different regions of the surface. Although favorable interactions are observed between amino acids and the graphene surface, the entropy-enthalpy compensation exhibits dependence on the molecular size of the adsorbates. For small amino acids, favorable enthalpy changes predominantly determine their adsorption behavior; however, larger amino acids tend to bind more tightly with the graphene surface, which is thermodynamically dominated by the entropy variations despite the structural characteristics of amino acids. This study reveals specific entropy-enthalpy mechanisms underlying amino acid adsorption at the solid-liquid interface, providing guidance for surface design and synthesis of new biomolecules.

PHKG2 regulates RSL3-induced ferroptosis in Helicobacter pylori related gastric cancer.

Ferroptosis is a newly discovered form of regulatory cell death induced by iron-dependent lipid peroxidation. Infection with Helicobacter pylori (H. pylori) is regarded as a high-risk factor for the development of gastric cancer (GC) and is associated with an increase in the levels of reactive oxygen species with activation of oncogenic signaling pathways. However, whether GC arising in the context of infection with H. pylori is correlated with ferroptosis is still unknown. In this study, we demonstrate that H. pylori infection increased the sensitivity of GC cells to RSL3 (RAS-selective lethal3)-induced ferroptosis. The molecular subtypes mediated by ferroptosis-related genes are associated with tumor microenvironment (TME) cell infiltration and patient survival. Importantly, we identified that the expression of phosphorylase kinase G2 (PHKG2) was remarkably correlated with H. pylori infection, metabolic biological processes, patient survival and therapy response. We further found the mechanism of H. pylori-induced cell sensitivity to ferroptosis, which involves PHKG2 regulation of the lipoxygenase enzyme Arachidonate 5-Lipoxygenase (ALOX5). In conclusion, PHKG2 facilitates RSL3-induced ferroptosis in H. pylori-positive GC cells by promoting ALOX5 expression. These findings may contribute to a better understanding of the unique pathogenesis of H. pylori-induced GC and allow for maximum efficacy of genetic, cellular, and immune therapies for controlling ferroptosis in diverse contexts.

Development of a sensitive droplet digital PCR according to the HPV infection specificity in Chinese population.

HPV16 and 18 are positively correlated with cervical carcinogenesis. However, HPV prevalence tends to vary according to region, nationality, and environment. The most prevalent high-risk (HR) HPV genotypes are HPV16, 52, 58, 56, 18, 33, and 45), while the low-risk (LR) genotypes are HPV6 and 11 in the Chinese population. Importantly, undetectable low-copy HPV DNA could be an important indicator of integration into the human genome and may be a precursor to cancer progression. The HPV viral load changes dramatically, either increasing or decreasing rapidly during carcinogenesis, and traditional quantitative real-time PCR (qPCR) cannot accurately capture this subtle change. Therefore, in this study, a reliable droplet digital PCR (ddPCR) method was developed to simultaneously detect and quantify HPV genotypes. The ddPCR quantitative results showed high accuracy, sensitivity, and specificity compared to qPCR results employing the same clinical specimens and supplemented the ddPCR assay for HPV52/56/58/6 genotypes according to the infection specificity of the Chinese population. In summary, this procedure is valuable for quantifying HPV DNA, especially under conditions of low template copy number in cervical intraepithelial neoplasia (CIN) and/or cervical cancer. Additionally, this method can dynamically observe the prognosis and outcome of HPV infection and thus be used as an effective means for real-time monitoring of tumor load.

Physical insight into the entropy-driven ion association.

The ion association is widely believed to be dominated by the favorable entropy change arising from the release of water molecules from ion hydration shells. However, no direct thermodynamic evidence exists to validate the reliability and suitability of this view. Herein, we employ complicated free energy calculations to rigorously split the free energy including its entropic and enthalpic components into the water-induced contributions and ion-ion interaction terms for several ion pairs from monatomic to polyatomic ions, spanning the size range from small kosmotropes to large chaotropes (Na+ , Cs+ , Ca2+ , F- , I- , CO3 2- , and HPO4 2- ). Our results successfully reveal that though ion associations are indeed determined by a delicate balance between the favorable entropy variation and the repulsive enthalpy change, the entropy gain dominated by the solvent occurs only for the monatomic ion pairing. The water-induced entropic contribution significantly goes against the ion pairing between polyatomic anion and cation, which is, alternatively, dominated by the favorable entropy from the ion-ion interaction term, due to the configurational arrangement of polyatomic anions involved in ion association. The structural and dynamic analysis demonstrates that the entropy penalty from the water phase is primarily ascribed to the enhanced stability of water molecules around the cation imposed by the incoming anion. Our study successfully provides a fundamental understanding of water-mediated ion associations and highlights disparate lengthscale dependencies of the dehydration thermodynamics on the specific types of ions.

WDHD1 facilitates G1 checkpoint abrogation in HPV E7 expressing cells by modulating GCN5.

BACKGROUND: Genomic instability is a hallmark of cancer. The G1 checkpoint allows cells to repair damaged DNA that may lead to genomic instability. The high-risk human papillomavirus (HPV) E7 gene can abrogate the G1 checkpoint, yet the mechanism is still not fully understood. Our recent study showed that WDHD1 (WD repeat and high mobility group [HMG]-box DNA-binding protein 1) plays a role in regulating G1 checkpoint of E7 expressing cells. In this study, we explored the mechanism by which WDHD1 regulates G1 checkpoint in HPV E7 expressing cells. METHODS: NIKS and RPE1 derived cell lines were used. Real-time PCR, Rescue experiment, FACS and BrdU labeling experiments were performed to examine role of GCN5 in G1 checkpoint abrogation in HPV-16 E7 expressing cells. RESULTS: In this study, we observed that WDHD1 facilitates G1 checkpoint abrogation by modulating GCN5 in HPV E7 expressing cells. Notably, depletion of WDHD1 caused G1 arrest while overexpression of GCN5 rescued the inhibitory effects of WDHD1 knockdown on G1/S progression. Furthermore, siWDHD1 significantly decreased cell cycle proliferation and DNA synthesis that was correlated with Akt phosphorylation (p-Akt), which was reversed by GCN5 overexpression in HPV E7 expressing cells. CONCLUSIONS: In summary, our data identified a WDHD1/GCN5/Akt pathway leading to the abrogation of G1 checkpoint in the presence of damaged DNA, which may cause genomic instability and eventually HPV induced tumorigenesis.

A Novel Signature Based on m6A Regulator-Mediated Genes Along Glycolytic Pathway Predicts Prognosis and Immunotherapy Responses of Gastric Cancer Patients.

N6-methyladenosine (m6A) modification is involved in many aspects of gastric cancer (GC). Moreover, m6A and glycolysis-related genes (GRGs) play important roles in immunotherapeutic and prognostic implication of GC. However, GRGs involved in m6A regulation have never been analyzed comprehensively in GC. Herein, the study aims to identify and validate a novel signature based on m6A-related GRGs in GC patients. Therefore, a m6A-related GRGs signature is established, which can predict the survival of patients with GC and remain an independent prognostic factor in multivariate analyses. Clinical significance of the model is well validated in internal cohort and independent validation cohort. In addition, the expression levels of risk model-related GRGs in clinical samples are validated. Consistent with the database results, all model genes are up-regulated in expression except DCN. After regrouping the patients based on this risk model, the study can effectively distinguish between them in respect to immune-cell infiltration microenvironment and immunotherapeutic response. Additionally, candidate drugs targeting risk model-related GRGs are confirmed. Finally, a nomogram combining risk scores and clinical parameters is created, and calibration plots show that the nomogram can accurately predict survival. This risk model can serve as a reliable assessment tool for predicting prognosis and immunotherapeutic responses in GC patients.

Viral aetiology in adults with acute upper respiratory tract infection in Jinan, Northern China.

Our study investigated the epidemiology of respiratory viruses in adult patients with upper respiratory tract infection (URTI) between August 2009 and September 2010 in Jinan, northern China. Nasal and throat swabs (n = 596) were collected from adult patients with URTIs. Nine respiratory-related viruses, including IFV, PIV, HRV, HMPV, HBoV, HCoV, ADV, RSV, and EV, were detected in all samples by conventional and reverse transcription polymerase chain reactions. Positive detection rate for respiratory virus was 38.76% and codetection rate was 4.70% in adults with acute respiratory tract infections. IFV (20.81%) was the dominant agent detected and IFVB had a higher incidence (12.58%) than IFVA (7.72%). Detection rates of 8.22%, 5.03%, 3.69%, and 2.52% were observed for HBoV, HRV, EV, and RSV, respectively. HCoV had the lowest detection rate of 0.50%. HBoV, HRV, EV, and ADV infection rates were higher in the 14-25-year-old group than in the 26-65-year-old group. Codetection rates were higher (7.52%) in the 14-25-year-old group than in the older age group (2.64%). The spectrum of respiratory virus infection in adult patients with URTIs was different in Jinan compared with other cities in China.

Functions and modulation of PKM2 activity by human papillomavirus E7 oncoprotein (Review).

Most tumor cells still exhibit active glucose uptake and glycolysis under aerobic conditions, a phenomenon known as the Warburg effect or aerobic glycolysis. Pyruvate kinase, one of the key enzymes in the cell glycolysis pathway, can promote the conversion of glucose to pyruvate and produce energy. Pyruvate kinase M2 (PKM2), a competitive PK subtype, is an important regulator of the aerobic glycolysis pathway in tumor cells and plays a direct role in gene expression and cell cycle regulation. Human papillomavirus (HPV) persistence is the main risk factor for cervical cancer. In recent years, it has been discovered that HPV plays an important role in malignant anal tumors and oral cancer. HPV oncoprotein E7 can promote the Warburg effect and produce a large amount of ATP, which may meet the energy requirements of cancer cell division. There appears to be a regulatory relationship between HPV E7 and PKM2, but the specific mechanism is mostly unknown. The present review article discusses the role of HPV E7 in transcriptional regulation, enzyme activity regulation, protein kinase activity regulation, post-translational modification and the immune microenvironment of PKM2 in the occurrence and development of cervical cancer.

Seroprevalence of hepatitis C virus in Jinan, China, 2008-2020.

BACKGROUND: The updated estimates of hepatitis C virus (HCV) seroprevalence are critical for developing strategies to manage or eliminate HCV infection. METHODS: A comprehensive study on HCV seroprevalence was conducted among 365,210 patients at Jinan Central Hospital, China, from 2008 to 2020. The patients were tested for anti-HCV, HCV core antigen, hepatitis B surface antigen, syphilis antibody, human immunodeficiency virus antigen + antibody, antihepatitis A virus IgM, and antihepatitis E virus IgM. RESULTS: HCV seroprevalence was 0.79% and was related to age. HCV seropositivity was lower in children (aged < 18 years) than in adults (aged ≥ 18 years) (0.15% vs. 0.81%). High HCV prevalence was reported in adults aged ≥ 41 years, and HCV seropositivity in those aged 41-80 years accounted for 74.56% of all seropositive individuals. Notably, the rate of HCV-HIV coinfection was 0. HCV seroprevalence was considerably higher in patients at the Kidney Disease Unit and Dialysis Department than in those at other departments (inpatient or outpatient). CONCLUSIONS: HCV seroprevalence was lower in Jinan region but higher in patients at the Kidney Disease Unit and Dialysis Department, especially in those undergoing hemodialysis.

A novel clinical-imaging nomogram for predicting primary aldosteronism in patients with hypertension.

This study aimed to develop and validate the accuracy of a clinical-imaging index nomogram in predicting primary aldosteronism (PA) in patients with hypertension. This case-control study enrolled 404 hypertension patients in the First Affiliated Hospital of Nanjing Medical University, China, from April 2017 to September 2021. The patients were randomly divided into the training set (n = 283, 70%) and the validation set (n = 121, 30%). Univariate and multivariate logistic regression analyses were performed to identify independent predictors of PA, which were then used construct a nomogram. The receiver operating characteristic (ROC) curve and calibration plot were drawn to assess the predictive value. The accuracies of our nomogram and other known prediction models were compared using decision curve analyses (DCA). Four significant variables (history of hypokalemia [OR = 2.684, 95% CI: 1.281-5.623, P < 0.001], typical imaging feature [OR = 2.316, 95% CI: 1.166-4.601, P = 0.003], 24 h urine potassium [OR = 0.956, 95% CI: 0.932-0.980, P < 0.001], plasma renin activity [PRA] [OR = 1.423, 95% CI: 1.161-1.744, P < 0.001]) in the multivariate logistic regression analysis were sifted out, and used to build the nomogram. The predictive nomogram yielded an AUC of 0.890 (95% CI, 0.853-0.927) in the training set and 0.860 (95% CI, 0.793-0.927) in the validation set. Predicted and actual probability of PA matched well in the nomogram. Moreover, the DCA showed that the nomogram gained a net benefit in clinical practice in predicting PA when the threshold value was set between 0.1 and 1.0. Our four-variable nomogram was accurate in predicting PA patients and might be introduced into clinical management.

Effect of Low Temperature on Insecticidal Protein Contents of Cotton (Gossypium herbaceum L.) in the Boll Shell and Its Physiological Mechanism.

Low temperature is the main factor for global natural disasters affecting the growth and distribution of plants, and cotton may be affected by low temperature and cold damage at all growth stages. In addition, the insecticidal resistance of cultivars has been reported to perform poorly or unstably due to adverse environments. The present study aimed to investigate the impact of low temperature on the levels of insecticidal protein in Bacillus thuringiensis (Bt) transgenic cotton plants during the peak boll stage. To achieve this, two Bt cotton cultivars, Sikang1 (SK1) and Sikang3 (SK3), were subjected to different temperature regimes and durations. The findings of the study demonstrated that the expression of insecticidal protein in the boll shell of Bt transgenic cotton plants was significantly inhibited under low-temperature stress. Specifically, in 2020, compared to the CK (27 °C), the insecticidal protein content in the boll shell of SK3 decreased by 28.19% after a 48 h of a 16 °C temperature. These results suggest that low-temperature stress can negatively impact the expression of insecticidal protein in Bt transgenic cotton, highlighting the need for appropriate measures to minimize its adverse effects on cotton production. In addition, the threshold temperature that leads to a significant decrease in the content of insecticidal proteins symbolizes an upward trend as the duration of stress prolongs. Decreased Bt protein content at low temperatures is associated with changes in the N metabolism. The present study revealed a significant positive correlation between the levels of glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities, as well as in the soluble protein levels in the boll shell and the content of the Bt protein. On the other hand, a significant negative correlation was observed between the levels of free amino acids, peptidase, and protease activities, as well as of Bt protein content. These findings suggest that, in Bt cotton production, it is crucial to remain vigilant of prolonged low-temperature disasters, which last for over 12 h and drop below 17-20 °C during the peak boll stage. Such conditions may reduce insecticidal resistance, leading to substantial economic losses.

Association and mechanism of garlic consumption with gastrointestinal cancer risk: A systematic review and meta-analysis.

Gastrointestinal cancer is one of the most commonly diagnosed cancer type worldwide, with millions of cases per year. The aim of this review was to investigate the relationship between garlic intake and the risk reduction of gastrointestinal cancer. We performed saturated data mining on various public domain databases, including PubMed (https://pubmed.ncbi.nlm.nih.gov/), Embase (https://www.embase.com/landing?status=grey), and Cochrane Library (https://www.cochranelibrary.com/), with key terms including: 'garlic', 'allium', 'stomach', 'gastric', 'colon', 'neoplasms', 'cancer' and 'tumor'. Furthermore, we identified additional references through expert manual curation. Finally, a meta-analysis was conducted to determine whether garlic intake reduces the risk of gastric and/or colorectal cancer. The association between garlic intake and reduction in the risk of gastric cancer [odds ratio (OR)=0.65, 95% confidence interval (CI)=0.49-0.87, P<0.001] were clear. Nine studies on garlic intake and colorectal cancer showed that garlic reduced cancer risk with a statistical significance (OR=0.75, 95% CI=0.65-0.87, P<0.001). We summarized that four main organic sulfides in garlic, diallyl disulfide (DADS), diallyl trisulfide (DATS), S-allylmercaptocysteine (SAMC) and allicin, may contribute to the regulation of tumor cell apoptosis, migration and the cell cycle. We identified the association between garlic intake and reduced risk of gastric and colorectal cancers and hypothesized that the active ingredients in garlic may act on multiple pathways to reduce the risk of gastrointestinal tumors according to published papers. Importantly, the potential tumor-preventing effect of these garlic ingredients warrants further investigation in regards to the specific mechanism of the underlying antitumor activities.

Opinion Polls and Antibody Response Dynamics of Vaccination with COVID-19 Booster Vaccines.

As the third year of the global COVID-19 pandemic, vaccination remains the most effective tool against infections and symptomatic illness. Comprehension regarding immunity to SARS-CoV-2 is limited, and the durability of immune responses after vaccination is currently not clear. In this study, we randomly collected 395 questionnaires to analyze the current state of COVID-19 vaccination. At the same time, the serum of 16 individuals who had received two doses of the COVID-19 vaccine were collected at different times before and after the booster vaccination. We analyzed the dynamic changes of SARS-CoV-2 S-specific binding antibodies in serum and immunological indicators. By collecting public opinion surveys and analyzing variational trends of SARS-CoV-2 S-specific binding antibodies and immune indicators after COVID-19 booster vaccination, we endeavored to demonstrate the concerns affecting people's booster vaccinations, as well as the frequency, timing, and necessity of COVID-19 booster vaccinations. The analysis of antibody results in 16 vaccinated volunteers showed that the antibody concentration decreased six months after the second dose and the protective effect of the virus was reduced. The third dose of COVID-19 vaccination is necessary to maintain the antibody concentration and the protective effect of the virus. The vaccination with the vaccine booster depends not only on the time interval but also on the initial concentration of the SARS-CoV-2 S-specific binding antibody before the booster. Our study has important implications for raising public awareness of vaccinating against SARS-CoV-2 and the necessity of COVID-19 booster vaccinations.

Sensitivity evaluation of 2019 novel coronavirus (SARS-CoV-2) RT-PCR detection kits and strategy to reduce false negative.

The early detection and differential diagnosis of respiratory infections increase the chances for successful control of COVID-19 disease. The nucleic acid RT-PCR test is regarded as the current standard for molecular diagnosis. However, the maximal specificity confirmation target ORF1ab gene is considered to be less sensitive than other targets in clinical application. In addition, recent evidence indicated that the initial missed diagnosis of asymptomatic patients with SARS-CoV-2 and discharged patients with "re-examination positive" might be due to low viral load, and the ability of rapid mutation of SARS-CoV-2 also increases the rate of false-negative results. Moreover, the mixed sample nucleic acid detection is helpful in seeking out the early community transmission of SARS-CoV-2 rapidly, but the detection kit needs ultra-high detection sensitivity. Herein, the lowest detection concentration of different nucleic acid detection kits was evaluated and compared to provide direct evidence for the selection of kits for mixed sample detection or make recommendations for the selection of validation kit, which is of great significance for the prevention and control of the current epidemic and the discharge criteria of low viral load patients.

Transmission Routes Analysis of SARS-CoV-2: A Systematic Review and Case Report.

The global outbreak of SARS-CoV-2 spread rapidly throughout the world which transmitted among humans through various routes. Asymptomatic (carriers) and possible fecal-oral transmission, resulted into a large-scale spread. These issues pose great challenges to disease diagnosis and epidemic control. We obtained data on 29 cases of COVID-19 patients in Jinan, China, and reported the clinical data of asymptomatic patients confirmed with stool samples positive. Some patients with gastrointestinal infections are secondary to pulmonary infections, and during the patients' recovery period, the virus may still existin the patient's gastrointestinal tract over 7 days. We combined with epidemiological and clinical data of asymptomatic patients to analyze the possible routes of viral transmission and infection, including eyes-nose, hands-eyes, fecal-oral, and eyes-oral, et al., thus first presented the two-way transmission through eyes-oral. Through associating infection symptoms with the transmission routes of virus and the patient course of the disease, we expect to provide guidelines for clinical diagnosis and the basis for suppressing the spread of the virus and antiviral treatment.

Preservative effects of fish gelatin coating enriched with CUR/ßCD emulsion on grass carp (Ctenopharyngodon idellus) fillets during storage at 4 °C.

This study investigated the effects of a novel edible coating combining fish gelatin with curcumin/ß-cyclodextrin (CUR/ßCD) emulsion on the quality of grass carp fillets (GCFs) during storage at 4 °C. For all samples, the quality parameters, including weight loss, pH, total volatile basic nitrogen (TVB-N), peroxide value (PV), thiobarbituric acid (TBA) value, SDS-PAGE, free amino acids (FAA), microbiological (total viable counts (TVC), Pseudomonas counts, yeasts and molds, and H2S-producing bacteria), color and sensorial characteristics, were tested periodically. The coatings containing CUR/ßCD emulsions exhibited better preservative effects than gelatin/ßCD coating. Therefore, fish gelatin coating enriched with CUR/ßCD emulsion can be used as an effective way to maintain the quality of GCF and extend its shelf life during storage at 4 °C.

Patients With LR-HPV Infection Have a Distinct Vaginal Microbiota in Comparison With Healthy Controls.

Condyloma acuminatum (CA) is a benign epithelium hyperplasia mainly caused by human papillomavirus (HPV), which is now the second most common viral sexually transmitted infection (STI) in China. In total, 90% of CA patients are caused by the low-risk HPV 6 and 11. Aside from low-risk HPV infection there are likely other factors within the local microenvironment that contribute to CA and there has been related research before. In this study, 62 vaginal specimens were analyzed using 16S rRNA gene sequencing. The diversity of the vaginal microbiota was higher and the composition was different with LR-HPV infection. While the relative abundance of dominant Firmicutes was lower, Actinobacteria, Proteobacteria, and Fusobacteria phyla were significantly higher; at the genus level Gardnerella, Bifidobacterium, Sneathia, Hydrogenophilus, Burkholderia, and Atopobium were higher. This study firstly confirmed a more accurate and comprehensive understanding of the relationship between low-risk HPV infection and vaginal microbiota, in order to provide a theoretical basis for further research on the occurrence and development of CA.

Antitumor effect of a polysaccharide isolated from Phellinus pullus as an immunostimulant.

The antitumor function of fungal polysaccharides is a popular area of interest in the research field due to their high efficiency and low side effects. The main mechanism of fungal polysaccharides is immune enhancement. The polysaccharose (APS-3) was extracted from the fruit body of Phellinus pullus. The proliferation inhibition to mouse sarcoma 180 (S180) tumor cells was studied by the MTT method. Mice models of transplanted S180 tumor were established and treated with APS-3 to verify the antitumor activity in vivo. Natural killer (NK) and lymphokine-activated killer (LAK) cytotoxicities of the mice were evaluated by the lactate dehydrogenase method. APS-3 can significantly inhibit the proliferation of the S180 cells. Cells could be completely inhibited by 1.6 mg/ml APS-3 after 24 h treatment. After 18 days of treatment, the antitumor rate of the high-dose group was 85.47%. Histopathology detection showed that for the APS-3-treated mice, the tumor cells dissolved, and exhibited a large range of structureless necrotic areas. NK and LAK cytotoxicities of the APS-3 treated mice increased by 61.85 and 56.16%, respectively, compared with the normal control mice. APS-3 can be used as an antitumor agent by way of immune enhancement.

Development of a loop-mediated isothermal amplification method for rapid detection of streptococcal pyrogenic exotoxin B.

We developed a visual loop-mediated isothermal amplification (LAMP) technique to detect the streptococcal pyrogenic exotoxin B (speB) gene. Fifteen strains (from American Type Culture Collection or clinical isolates) were used to determine the specificity and sensitivity of the LAMP assay. Clinical samples were collected from 132 patients with suspected Streptococcus pyogenes (S. pyogenes) infection to verify the feasibility of the LAMP assay for detection of the speB gene. By using a set of five primers (a pair of outer primers, a pair of inner primers and one loop primer) targeting the speB gene, the amplification reaction was rapidly performed in a regular water bath under isothermal conditions at 63 °C for approximately 60 min. Only the two S. pyogenes strains showed positive results which were easily observed with the naked eye, and the other strains showed negative results. The detection limit of the LAMP assay was 0.01 ng/µl of template, showing higher sensitivity than conventional PCR (with a detection limit of 1.0 ng/µl). The detection rate of the speB gene in clinical samples was 71.21% and was consistent with the PCR results. The rapid detection of the speB gene by the LAMP assay is highly specific and sensitive, is simple to perform and cost-effective, and is expected to be a new reliable method for the rapid diagnosis of S. pyogenes infection, that is particularly suitable for rural or community hospitals in developing countries.

Activation of the intrinsic apoptosis pathway contributes to the induction of apoptosis in hepatocellular carcinoma cells by valproic acid.

The level of histone deacetylation is closely associated with the genesis and development of tumors, but the antitumor effect and mechanism of the class I histone deacetylase inhibitor (HDACI) valproate acid sodium (VPA) on hepatocellular carcinoma cells has not been clearly demonstrated. In the present study, the antitumor effect and mechanism of VPA were measured in vitro. Firstly, it was found that, as an HDAC inhibitor, VPA could inhibit HDAC activity and HDAC1 gene expression in hepatocellular carcinoma cells and, as a result, an inhibition of cell proliferation was detected by MTT assay. Subsequently, the cell cycle and cell apoptosis profiles were analyzed using flow cytometry (FCM). The expression of the mRNA and protein of cyclins A, D1 and E and P21Waf/cip1 was measured by reverse transcription-polymerase chain reaction and FCM analysis to determine the molecular mechanism of VPA-induced cell cycle arrest. The activity and mRNA and protein expression of caspases 3, 8 and 9 were detected to determine the apoptotic pathway. Caspase expression was blocked by caspase inhibitors in order to observe whether the intrinsic or extrinsic pathway contributed to HepG2 cell apoptosis. The results revealed that the mRNA and protein expression of cyclins A and D1 was downregulated while the expression of P21Waf/cip1 was upregulated by VPA. The expression of cyclin E was only slightly affected by VPA. The mRNA and protein expression and activity of caspases 3 and 9 were upregulated by VPA. By contrast, inhibitors of caspases 3 and 9 could reverse cell apoptosis and there was no notable change in caspase 8 expression in any of these experiments. The intrinsic apoptosis pathway, but not the death receptor pathway, contributed to the induction of apoptosis in hepatocellular carcinoma cells. Furthermore, VPA could inhibit the proliferation of hepatocellular carcinoma cells by inducing G1 phase arrest and cell apoptosis. These effects were attributed to the change in the caspase level.