[Epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023].

Objective: To understand the epidemiological characteristics of human respiratory syncytial virus (HRSV) among acute respiratory infection (ARI) cases in 16 provinces of China from 2009 to 2023. Methods: The data of this study were collected from the ARI surveillance data from 16 provinces in China from 2009 to 2023, with a total of 28 278 ARI cases included in the study. The clinical specimens from ARI cases were screened for HRSV nucleic acid from 2009 to 2023, and differences in virus detection rates among cases of different age groups, regions, and months were analyzed. Results: A total of 28 278 ARI cases were enrolled from January 2009 to September 2023. The age of the cases ranged from<1 month to 112 years, and the age M (Q1, Q3) was 3 years (1 year, 9 years). Among them, 3 062 cases were positive for HRSV nucleic acid, with a total detection rate of 10.83%. From 2009 to 2019, the detection rate of HRSV was 9.33%, and the virus was mainly prevalent in winter and spring. During the Corona Virus Disease 2019 (COVID-19) pandemic, the detection rate of HRSV fluctuated between 6.32% and 18.67%. There was no traditional winter epidemic peak of HRSV from the end of 2022 to the beginning of 2023, and an anti-seasonal epidemic of HRSV occurred from April to May 2023. About 87.95% (2 693/3 062) of positive cases were children under 5 years old, and the difference in the detection rate of HRSV among different age groups was statistically significant (P<0.001), showing a decreasing trend of HRSV detection rate with the increase of age (P<0.001). Among them, the HRSV detection rate (25.69%) was highest in children under 6 months. Compared with 2009-2019, the ranking of HRSV detection rates in different age groups changed from high to low between 2020 and 2023, with the age M (Q1, Q3) of HRSV positive cases increasing from 1 year (6 months, 3 years) to 2 years (11 months, 3 years). Conclusion: Through 15 years of continuous HRSV surveillance analysis, children under 5 years old, especially infants under 6 months old, are the main high-risk population for HRSV infection. During the COVID-19 pandemic, the prevalence and patterns of HRSV in China have changed.

[Epidemiological characteristics of influenza and characteristics of hemagglutinin gene of B-Victoria strains in Hebei Province from 2018 to 2019].

Objective: To understand the epidemiological characteristics of influenza in Hebei Province from 2018 to 2019, and to analyze the characteristics and variation of hemagglutinin(HA) gene of influenza B-Victoria(BV) strains. Methods: Throat swab specimens of influenza-like cases within 3 days of fever were collected from 28 sentinel hospitals in Hebei province, meanwhile, The surveillance data was collected by the Chinese National Influenza Surveillance Network from April 2018 to March 2019, Throat swab specimens were collected from patients with influenza-like symptoms in sentinel hospitals, and tested by RT-PCR and virus isolation. 14 influenza B-Victoria strains from different regions were selected to sequence HA gene, Phylogenetic tree and the molecular characteristics were analyzed by DNASTAR 7.0 and Mega-X software. Results: From 2018 to 2019, A total of 99 266 cases of influenza-like illness (ILI) were detected from 4 689 103 cases by 28 influenza sentinel hospitals in Hebei Province, the visit percentage of ILI was 2.12%. During the period, 18 730 samples were detected, and 2 752(14.69%) samples were positive tested by RT-PCR, the peak was in the third week of 2019(44.92%), In the early stage of epidemic season, Influenza A(H1N1)pdm09 virus was the main type, while BV virus was the main type in the late stage. HA gene sequence analysis showed that the 14 BV viruses belonged to 162-164 amino acid deletion strains, the amino acid homology between HA sequences was 97.16%-100.00%, and 97.16%-98.95% compared with the vaccine strain B/Colorado/06/2017 recommended by WHO. Compared with the vaccine strains, 14 strains involved 11 amino acid site mutations. Conclusion: Influenza was prevalent in winter and spring in Hebei province from 2018 to 2019, Multiple mutations in antigenic sites of BV viruses might be related to the outbreaks.

Increased miR-142 and decreased DJ-1 enhance the sensitivity of pancreatic cancer cell to adriamycin.

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Increased miR-142 and decreased DJ-1 enhance the sensitivity of pancreatic cancer cell to adriamycin, by G.-Y. Han, J.-H. Cui, S. Liang, H.-L. Li, published in Eur Rev Med Pharmacol Sci 2018; 22 (22): 7696-7703-DOI: 10.26355/eurrev_201811_16390-PMID: 30536312" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/16390.

Targeting of GSK-3ß by miR-214 to facilitate gastric cancer cell proliferation and decrease of cell apoptosis.

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Targeting of GSK-3ß by miR-214 to facilitate gastric cancer cell proliferation and decrease of cell apoptosis, by H.-L. Li, S. Liang, J.-H. Cui, G.-Y. Han, published in Eur Rev Med Pharmacol Sci 2018; 22 (1): 127-134-DOI: 10.26355/eurrev_201801_14109-PMID: 29364479" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/14109.

An office building outbreak: the changing epidemiology of tuberculosis in Shenzhen, China.

Tuberculosis (TB) is generally considered a disease that principally afflicts the low-income segments of a population. In the Nanshan District of Shenzhen, China, with the economic transformation and a new Headquarters Economy (HE) emerging, there are now more cases in office workers than in manufacturing workers. To illustrate this trend, we describe a small TB outbreak in an office building located in the centre of the rapidly growing HE district. Two active pulmonary tuberculosis cases were found in workers who shared an office, and whole genome sequencing showed that the genetic distance between the strains of the two cases was just one single nucleotide polymorphism, consistent with intra-office transmission. Investigation of 30 other workers in the same or adjacent offices with interviews, interferon-gamma release assays (IGRAs) and chest X-rays, identified one new TB case and latent tuberculosis infection (LTBI) in 40.0% (12/30) of the contacts. The offices were under-ventilated. None of the IGRA positive, asymptomatic contacts agreed to receive treatment for LTBI, presumably due to TB stigma, and over the next 2 years 69.0% (20/29) of the contacts were lost to follow-up. Treatment for LTBI and stigma of TB remain challenges here. Office workers in the HE of rapidly economic developing areas should be targeted with increased vigilance by TB control programmes.

[Mechanism relevant to hepatocellular carcinoma occurrence after negative conversion of viral DNA in treatment of chronic hepatitis B patients with nucleos(t)ide drugs].

Hepatocellular carcinoma (HCC) is a common malignant tumor in China, and most of the patients have a background of chronic HBV infection. Nucleos(t)ide drugs (NAs) are currently recommended by major guidelines as a first-line treatments for chronic hepatitis B. However, it is still clinically possible to observe that some patients who have acquired virological response (HBV DNA below the lower detection limit) after NAS treatment progress to HCC, and its mechanism of development is still unclear. In this review, the mechanism relevant to HCC progression in treatment of chronic hepatitis B patients with NAs is analyzed mainly from the aspects of gene integration and persistent inflammatory injury.

Increased miR-142 and decreased DJ-1 enhance the sensitivity of pancreatic cancer cell to adriamycin.

OBJECTIVE: Phosphatidylinositol-3 kinase (PI3K)/protein kinase B (AKT) signaling pathway is related to tumorigenesis by up-regulating survivin. Phosphatase and tensin homologue deleted on chromosome ten (PTEN) can suppress PI3K/AKT signaling pathway, while DJ-1 is the negative regulator of PTEN. DJ-1 up-regulation is closely correlated with the occurrence, progression, and drug resistance of pancreatic cancer. MicroRNA-142 (MiR-142) is significantly declined in pancreatic cancer tissue. Bioinformatics analysis demonstrated that complementary binding site exists between miR-142 and DJ-1. This investigation, therefore, aimed to study the role of miR-142 in the regulation of DJ-1-PTEN/PI3K/AKT/Survivin signaling pathway as well as in pancreatic cancer cell proliferation, apoptosis, and adriamycin (ADM) resistance. MATERIALS AND METHODS: Dual luciferase assay was performed to assess the targeted relationship between miR-142 and DJ-1. MiR-142, DJ-1, and PTEN expressions in SW1990 cells and drug-resistant SW1990/ADM cells were compared. SW1990/ADM cells were divided into five groups, including mimic-NC, miR-142 mimic, small interfere normal control (si-NC), si-DJ-1, and miR-142 mimic + si-DJ-1 groups. DJ-1, PTEN, phosphorylated-AKT (p-AKT), and Survivin expressions were tested. Cell apoptosis was determined by flow cytometry. Cell proliferation was evaluated by EdU staining. RESULTS: MiR-142 targeted inhibited DJ-1 expression. MiR-142, PTEN, and cell apoptosis significantly down-regulated, while DJ-1, p-AKT, Survivin, and cell proliferation significantly elevated in SW1990/ADM cells compared with SW1990 cells. MiR-142 mimics and/or si-DJ-1 transfection markedly reduced DJ-1, p-AKT, and Survivin expressions enhanced PTEN level, attenuated cell proliferation, enhanced cell apoptosis, and weakened ADM resistance. CONCLUSIONS: MiR-142 over-expression weakened ADM resistance in pancreatic cancer cells by targeting DJ-1 to enhance PTEN expression and attenuate PI3K/AKT signaling pathway activity.

[Association of α-actinin-3 gene polymorphism and muscle strength of postmenopausal women].

Objective: To explore the association between α-actinin-3 (ACTN3) polymorphism and muscle strength in postmenopausal women. Methods: Five hundred and ninety-eight postmenopausal women with an average of (62.9±7.0) years old in Dongcheng District of Beijing were included. The ACTN3 polymorphism including rs540874, rs618838 and rs2229456 were genotyped by Sequenom Mass Array to explore their associations with muscle strength. One hundred and sixty-three of them were trained with regular Tai chi movement while 271 were administered with elemental calcium 600 mg/d combined with Vitamin D 800 U/d or calcitriol 0.25 µg/d for 2 years. Association between changes of muscle strength and ACTN3 polymorphism were analyzed. Results: The rs540874 genotypes were found to be significantly associated with chair stand test[GG (9.02±3.85) s vs GA (9.27±4.14) s vs AA (9.68±5.00) s, P=0.015]. Right grip strength in women with G allele were likely to be higher compared with A allele, but it was not statistically significant (P=0.056). Multiple linear regression showed that the chair stand test of AA genotype was statistically longer than that of GG and GA genotype (ß=2.639, 95% CI: 1.632-4.646, P=0.010). The associations between rs618838, rs2229456 genotypes and muscle strength of both lower and upper limbs were not significant (all P>0.05). In addition, muscle strength of lower limbs of patients with rs540874 genotyped with G allele, rs618838 genotyped with C allele and rs2229456 genotyped with A allele increased significantly after enhanced exercise and vitamin D supplementation (all P<0.05). Conclusions: The rs540874 polymorphism of ACTN3 gene was associated with the muscle function of lower limb in postmenopausal women. The improvement of muscle strength after intervention were possibly correlated with rs540874, rs618838 and rs2229456 polymorphisms.

Tea Consumption Is Associated with Increased Bone Strength in Middle-Aged and Elderly Chinese Women.

OBJECTIVES: Previous studies found that tea consumption was related to a reduction in the risks of some chronic diseases, but limited data are available on bone health. This study aimed to examine the associations of tea consumption with hip bone strength in Chinese women. DESIGN: Cross-sectional study. SETTING: The participants were from the ongoing Guangzhou Nutrition and Health Study. This was a cohort study started in 2008. The examination data conducted between June 2010 and December 2013 were used. PARTICIPANTS: A total of 1,495 Chinese women aged more than 40 years were included. MEASUREMENTS: Tea consumption, socio-demographic information and lifestyle habits were collected by a face-to-face questionnaire. Hip bone mineral density (BMD) and geometric parameters, i.e. cross-sectional area (CSA), section modulus (Z) and buckling ratio (BR), were generated by dual-energy X-ray absorptiometry. The associations of tea consumption with bone phenotypes were detected by analysis of covariance and multiple linear regression models after adjusting for age, body mass index, years since menopause, physical activity, dietary-protein intake, dietary-calcium intake, calcium tablet intake, drinking status and smoking status. RESULTS: Tea drinkers (n = 732) had approximately 1.9% higher BMD (p < 0.05) and 3.6% lower BR (p < 0.05) than non-tea drinkers (n = 763). The dose-response relationships of BMD, BR or CSA with total tea consumption were identified (p-trend < 0.05). Tea drinking was found to be a significant and independent predictor of BMD (ß = 0.068, p < 0.05) or BR (ß = -0.079, p < 0.05). CONCLUSION: Tea consumption was associated with increased bone strength in middle-aged and elderly Chinese women.

Targeting of GSK-3ß by miR-214 to facilitate gastric cancer cell proliferation and decrease of cell apoptosis.

OBJECTIVE: Wnt/ß-catenin pathway regulates cell proliferation and apoptosis. GSK-3ß degrades ß-catenin and negatively regulates Wnt/ß-catenin pathway. A previous study indicated that the GSK-3ß expression was significantly reduced in gastric cancer, along with the increase of miR-214 expression. Bioinformatics analysis revealed complementary binding sites between miR-214 and 3'-UTR of GSK-3ß mRNA. This study investigated the regulatory role and related mechanism of miR-214 in the proliferation and apoptosis of gastric cancer cells. PATIENTS AND METHODS: Gastric cancer tissues were collected from patients and the expressions of miR-214, GSK-3ß and ß-catenin were determined. Dual luciferase reporter gene assay was used to study the regulatory role between miR-214 and GSK-3ß. Expressions of miR-214, GSK-3ß, ß-catenin and survivin from GES-1 and MKN-28 cells were detected. Flow cytometry was used to measure cell proliferation and apoptosis. In vitro cultured MKN-28 cells were treated with miR-214 inhibitor and/or pSicoR-GSK-3ß. Levels of GSK-3ß, ß-catenin and survivin were detected, cell apoptosis was evaluated by flow cytometry and proliferation was tested by EdU staining. RESULTS: Compared to normal gastric mucosa, the levels of miR-214 and ß-catenin were elevated, and the expression of GSK-3ß was decreased in gastric cancer tissues. Compared to GES-1 cells, the expressions of miR-214, ß-catenin and survivin in MKN-28 cells were upregulated, along with downregulation of GSK-3ß expression. The proliferation was enhanced whilst apoptosis was suppressed. After the transfection of miR-214 inhibitor and/or pSicoR-GSK-3ß, GSK-3ß expression was induced in MKN-28 cells while ß-catenin and survivin expressions were inhibited, along with the increase of cell apoptosis. CONCLUSIONS: MiR-214 decreases GSK-3ß expression and promotes the pathogenesis of gastric cancer. The inhibition of miR-214 reduces the proliferation of gastric cancer cells via upregulation of GSK-3ß and suppression of Wnt/ß-catenin signal pathway, which provides fundamental support for the future therapy of gastric cancer.

CD44V6 regulates gastric carcinoma occurrence and development through up-regulating VEGF expression.

OBJECTIVE: Gastric carcinoma (GC) is one of the most common malignant tumors around the world. It is featured as high morbidity, poor prognosis, and short survival, thus seriously threats to the quality of life. The mechanism of GC is still unclear, leading to a difficulty in the treatment. CD44V6 plays an important role in tumorigenesis and progression, while its role in GC still needs further elucidation. PATIENTS AND METHODS: GC tissue and para-carcinoma tissue were collected from patients in different tumor-mode-metastasis (TNM) stages. CD44V6 and vascular endothelial growth factor (VEGF) expressions were detected by real-time PCR and Western blot. Their correlations with the clinicopathological characteristics of GC were analyzed. GC cell line SGC-7901 was cultured in vitro and divided into control, scramble group, and CD44V6 small interfering RNA (siRNA) group. Cell proliferation was assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Cell apoptosis was evaluated by caspase 3 activity assay. RESULTS: CD44V6 and VEGF protein expressions significantly increased in GC tissue compared with adjacent normal control (p < 0.05). CD44V6 expression was correlated with differentiation, lymph node metastasis, and TNM staging (p < 0.05). CD44V6 was positively correlated with VEGF (p < 0.05). CD44V6 siRNA reduced CD44V6 and VEGF expressions in SGC-7901, inhibited cell proliferation, and enhanced caspase 3 activity compared with control (p < 0.05). CONCLUSIONS: CD44V6 participates in GC occurrence and development by up-regulating VEGF expression. Targeting CD44V6 regulates GC progression through inhibiting VEGF expression, promoting cell apoptosis, and restraining cell proliferation.

Detection of hereditary hearing loss gene by DNA microarray.

OBJECTIVE: Screening genes in patients suffering clinically sporadic deafness, using DNA microarray, and evaluating the application value of the clinical detection. PATIENTS AND METHODS: DNA extracted from patients' venous blood was amplified by PCR, and hybridization was carried out in a myriad class clean room. Nine mutation sites of four deaf genes commonly seen in Chinese people were tested. RESULTS: Among 24 patients, 7 cases with mutations were detected, with a positive rate of 29.17%. These include 4 cases with GJB2 gene mutation (16.67%), of which 1 case with 176 del 16 site heterozygous mutation; 1 with 235 del C site homozygous mutation; 2 with 299 del AT site heterozygous mutation; 1 with SLC26A4 gene IVS7-2A>G site heterozygous mutation (4.17%), 2 with mitochondrion 12SrRNA gene1555A>G site homogeneous mutation (8.33%). No GJB3 gene mutation was detected. CONCLUSIONS: Gene chip technology of hereditary hearing loss can detect related mutation sites of hearing loss rapidly and with high-throughput, which meets the demands of clinical deaf gene detection.

MIR-150 promotes prostate cancer stem cell development via suppressing p27Kip1.

OBJECTIVE: Our previous study found that high miR-150 expression was positively correlated with prostate tumor recurrence or metastasis. In this work, we investigated the expression of miR-150 in prostate cancer stem cells (CSCs) and explored its regulation over p27 in the development of CSCs. MATERIALS AND METHODS: MiR-150 expression in CD144 or CD44 positive primary prostate cells and in DU145 cell line was measured. It regulation over CSCs was measured using tumor sphere assay and qRT-PCR analysis of CSC related Oct4, Nestin and Nanog genes. The direct binding between miR-150 and 3'UTR of p27 mRNA was verified using dual luciferase, qRT-PCR and western blot assay. The influence of miR-150-p27 axis on prostate CSC properties was further investigated. RESULTS: Findings of this study found miR-150 expression was significantly upregulated in CD44+ or CD133+ subgroups of prostate cancer cells. MiR-150 could directly target 3'UTR of p27 and decrease its expression, through which it increased the number and volume of tumor sphere formed by DU145 cells, as well as the expression of CSC related Oct4, Nestin and Nanog genes. CONCLUSIONS: Increased miR-150 expression might participate in the development and progression of human prostate CSC by suppressing p27. This supported our previous study which found miR-150 was positively correlated with prostate tumor recurrence or metastasis.

Blockade of S100A3 activity inhibits murine hair growth.

Using mouse gene expression microarray analysis, we obtained dynamic expression profiles of the whole genome in a depilation-induced hair growth mouse model. S100A3 expression increased during the anagen phase and returned to normal during the telogen phase. The effects of S100A3 blockade on the hair growth cycle were examined in mice after subcutaneous injection of an anti-mouse S100A3 antibody. Protein localization of S100A3 was confined to the hair shafts during the anagen phase and the sebaceous glands during the telogen phase. S100A3 blockade delayed hair follicle entry into the anagen phase, decreased hair elongation, and reduced the number of hair follicles in the subcutis, which correlated with the downregulated expression of hair growth induction-related genes in vivo. The present study demonstrates that anti-S100A3 antibody inhibits mouse hair growth, suggesting that S100A3 can be used as a target for hair loss treatment.

Viscosupplementation of synovial fluid with xanthan gum for treatment of osteoarthritis and its clearance kinetics in the rabbit knee joint.

BACKGROUND: Injection of xanthan gum (XG) has been demonstrated to reduce the symptoms and progression of osteoarthritis (OA) in experimental models. Due to its high viscosity and stability, it may restore the rheological homeostasis of osteoarthritic synovial fluid (SF), and avoid numerous intra-articular injections. OBJECTIVE: The present study investigated the effect of XG on the rheological properties of SF, and determined its residence time in the rabbit joint cavity. METHODS: Rabbit knees were subject to intra-articular injection with XG or XG labeled with green fluorescence, and the SF was collected at different time. Rheological properties of SF with XG injected were compared with those with sodium hyaluronate injected. Resistance to oxidant damage was tested by adding H2O2 to the viscosupplement. Fluorescence intensity was measured for the SF with XG labeled with green fluorescence. RESULTS: Results showed that XG could significantly improve the SF viscosity at 24, 96, 168 h, and increase the storage moduli (G') and loss moduli (G″) tested at frequency of 0.5 and 2.5 Hz. SF with XG injection exhibited a gel-like behavior at 24 h, in that G' exceed G″ over the entire oscillation frequency range. XG preparation had a high resistance to oxidant damage. Half-life of XG in the joint cavity was 35.9 h, with clearance obeying first-order kinetics. CONCLUSIONS: Intra-articular injection of XG could improve the rheological properties of SF, and this effect could last for several days.

Molecular characterization of hepatitis A virus isolated from acute gastroenteritis patients in the Seoul region of Korea.

Hepatitis A virus (HAV) is a major public health problem throughout the world. As a result of declining HAV endemic in Korea, an increasing number of children and adolescents have become susceptible to HAV infection. HAV is related with sanitation conditions of the environment and is transmitted via the fecal-oral route, either through person-to-person contact or by contaminated water and food. The present study has been carried out to determine the phylogenetic analysis and circulating patterns of HAV strains detected from hospitalized patients with acute gastroenteritis (AGE) in the Seoul region of Korea. In total, 2,782 stool specimens from hospitalized patients with AGE collected in October 2006 to September 2007 in Seoul were tested for HAV. A pair comparison of the nucleic acid sequence of a 159-bp base region at the putative VP1/2A junction of 85 Seoul isolates revealed that the most common HAV strain circulating in the region during 2006-2007 was subgenotype IA. HAV phylogenetic studies can provide important information on the genetic characteristics of HAV from AGE patients who may subsequently become the source of infection in Korea.

Antimicrobial activity of Ca(OH)2 containing pastes with Enterococcus faecalis in vitro.

Sixty-eight standardized human root specimens were infected with Enterococcus faecalis for 3 wk after removal of the smear layer. After 3 wk of infection, the smear layer was reformed and in half of the specimens, the smear layer was again removed. Aqueous Ca(OH)2 paste and silicone oil based Ca(OH)2 paste were used as the test medications. The specimens were divided into four groups (i.e. (a) nonsmeared aqueous calcium hydroxide group, (b) nonsmeared silicon oil-based calcium hydroxide group, (c) smeared aqueous calcium hydroxide group, and (d) smeared silicon oil-based calcium hydroxide group. Medications were placed in the canals for 7 days. After removal of medications dentin chips were collected and incubated. The quantity of bacteria present was assessed. All calcium hydroxide pastes were effective in the elimination of bacteria in the dentinal tubules, except in the smeared group with silicone oil-based calcium hydroxide.

[Isolation and structure determination of xanthone glycosides of Anemarrhena asphodeloides].

Xilingzhimu, the rhizomes of Anemarrhena asphodeloides Bunge (Liliaceae), has been prescribed as antipyretic, anti-inflammatory, diuretic and hypoglycemic agents in Chinese traditional medicine. In this paper, two xanthone glycosides I and II, were isolated from Xilingzhimu by conventional method. The structures of I and II were identified on the basis of chemical reactions and UV, IR, 1HNMR, 13CNMR and DEPT. Compound I was identified as mangiferin and II is a new compound, named neomangiferin. Its structure is 7-O-beta-D-glucopyranosyl-mangiferin.

Elevation of intracellular Ca2+ concentration in rabbit nonpigmented ciliary epithelial cells by allicin.

A previous study has shown that allicin produces changes in aqueous humor dynamics, and this study was conducted to examine possible cellular mechanisms. In rabbit nonpigmented ciliary epithelial cells, basal levels of [Ca2+]i were determined to be 164 +/- 34 nM. Allicin, a sulfhydryl-reactive agent, induced Ca2+ transients at 0.01 mM and at 0.2 mM, the Ca2+ transient peaked at 732 +/- 35 nM. Allicin-induced Ca2+ transients were prevented by pretreatment with dithiothreitol which did not affect the basal Ca2+ levels. Allicin had only a slight, insignificant, effect on L-type Ca2+ currents, and allicin-induced Ca2+ transients were also present under extracellular Ca(2+)-free conditions. These data suggest that intracellular Ca2+ stores are the most probable source of allicin's effect. Pretreatment of cells with ryanodine, an inhibitor of Ca(2+)-induced-Ca(2+)-release, inhibited allicin-induced Ca2+ transients, but the basal Ca2+ levels were unaffected by ryanodine. Thus, allicin-induced Ca2+ transients are most likely mediated through ryanodine-sensitive intracellular Ca2+ stores.

A procedure for quantitative determination of tris(2-carboxyethyl)phosphine, an odorless reducing agent more stable and effective than dithiothreitol.

The concentration of tris(2-carboxyethyl)phosphine (TCEP) can be conveniently determined by measuring the amount of 2-nitro-5-thiobenzoate (NTB) formed after reaction with 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB). This method utilizes the fact that TCEP reduces DTNB rapidly and stoichiometrically to generate two equivalents of NTB which, in its anionic form, has a molar extinction coefficient of 14,150 M-1 cm-1 at 412 nm. This method is sensitive enough to detect the concentration of TCEP in the micromolar range and has proven useful in monitoring the stability or oxidation of TCEP under various conditions. TCEP is not only very stable in acidic solutions, but unlike dithiothreitol (DTT) which readily oxidizes above pH 7.5, it is also highly stable in basic solutions. The rates of reduction of DTNB by TCEP and DTT are compared in the pH range 6-9. Below pH 8, TCEP is significantly more effective than DTT in reducing this disulfide. The rates of reduction of 2,2'-dithiodipyridine (2,2'-DTDP) by TCEP and DTT are compared in the pH range 1.5-8.5. Unlike DTT which is totally inactive at pH 1.5, TCEP is still capable of reducing 2,2'-DTDP effectively at this pH. Thus, if TCEP and thiols are simultaneously present, the concentration of TCEP can be selectively determined by using 2,2'-DTDP at very low pH.