Distribution of thalassemias and associated hemoglobinopathies identified by prenatal diagnosis in Taiwan.

BACKGROUND: Hemoglobin (Hb) gene disorders are common hereditary disorders in Taiwan, and α- and ß-thalassemias are among the well-known Hb disorders here. Our study provides a primary reference for designing a locally relevant antenatal diagnostic test to control the spread of thalassemia. METHODS: Between 1998 and 2011, prenatal diagnoses for identifying thalassemia and hemoglobinopathies were performed on 1240 fetuses at risk for α-hydrops and ß-thalassemia major. RESULTS: Of 1240 specimens analyzed, 1082 (87%) were obtained by amniocentesis; 125 (10%), by chorionic villus sampling; and 33 (3%), by cordocentesis. Prenatal diagnoses revealed that 21.5% of these fetuses as thalassemia major (including α-thalassemia hydrops, ß-thalassemia major, and Hb E/ß-thalassemia); 50.2%, for thalassemia minor (include α-thalassemia carrier, ß-thalassemia carrier, and α-thalassemia combined ß-thalassemia carrier); and 28.3% for normal type (include non-α, ß-thalassemia). The most common α-hydrops were SEA (Southeast Asian) and Philippine type (frequencies of 74.91 and 5.24%, respectively). The frequency of the IVS-II-654 combined codons 41/42 mutation, the most common ß-thalassemia major mutation in this region, was 5.24%. Two fetuses were found with E/ß-thalassemia (HbE/IVS-II-654 and HbE/codons 41/42, respectively). Since 1993, Taiwan's Department of Health adopted a national program for screening pregnancies to control spread of thalassemia. In the last 10years, less than 3 such cases have occurred per year. After 2003, this number was 0 for a total of 4years (2003, 2004, 2007, and 2008). CONCLUSION: In Taiwan, incidence and frequency of thalassemia genotypes were similar to those previously reported. The national program for screening pregnancies to control spread of thalassemia that resulted in a marked decline in the number of newborns with thalassemia major. Interestingly, prenatal diagnoses revealed 21.5% for thalassemia major, 50.2% for thalassemia minor, 28.3% normal comparison of thalassemia type distribution showed normal type increasing by 13.2% and major type decreasing by 14%. This unique and significant finding needs further clinical studies and discussion to explain such a phenomenon.

Molecular epidemiology of the 2005 enterovirus 71 outbreak in central Taiwan.

BACKGROUND: Since 1998, Taiwan has experienced annual outbreaks of enterovirus 71 (EV71) nationwide. The area around Taichung City experienced a particularly large outbreak in 2005, after which EV71 disappeared for 2 y before re-emerging in 2008. Here we present the clinical, genotypic, and epidemiological baseline data for the 2005 Taichung outbreak. METHODS: Throat swab, stool and cerebrospinal fluid samples were collected and stored in viral transport medium. Samples were tested by reverse-transcriptase polymerase chain reaction and viral culture. Epidemiological, laboratory, and clinical data were extracted from medical record reviews. A total of 27 virus isolates were selected for phylogenetic analysis. RESULTS: Confirmed phylogenetic results of the viruses were separated into 5 groups. The 5'-UTR regions served as a focus for investigating genetic relationships among the 27 EV71 isolates, all of which belonged to a distinct clade in the C4 genotype. Most of the strains belonged to 5 observed epidemic groups. CONCLUSION: In conclusion, the 2005 outbreak in central Taiwan was caused by divergent EV71 strains belonging to the C4 genotype.

Molecular lesion frequency of hemoglobin gene disorders in Taiwan.

Hemoglobin (Hb) gene disorders are common inherited diseases in Taiwan. The α- and ß-thalassemias are among the well-known Hb diseases in this area. We reviewed abnormal hematological data in 3578 cases, identified between 1998 and 2009, as being at-risk for α-thalassemia (α-thal) (n = 1909; 53.3%), ß-thal (n = 743; 20.8%), non-α, ß-thal (n = 872; 24.4%), and α-thal combined with ß-thal (n = 54; 1.5%), and collected fetal blood samples for prenatal testing. The most common types of α(0)- and α(+)-thal were the SEA (Southeast Asian) deletion and the -α(3.7) rightward deletion, with frequencies of 87.79 and 4.85%, respectively. The frequency of the IVS-II-654 (C>T) mutation, the most common ß-thal mutation in this region, was 38.6%. Hb E [ß26(B8)Glu→Lys, GAG>AAG] was found to be the most common Hb variant, and it was concluded that Hb Tak [ß147 (+AC)], Hb G -Taichung (also known as Hb Q-Thailand) [α74(EF3)Asp→His, GAC>CAC (α1)], Hb Owari [α121(H4)Val→Met (GTG>ATG)], and Hb Phnom Penh [α117(GH5)Phe-Ile-α118(H1)Thr (α1)] were very rare. The results of this study provide a primary reference for designing a locally relevant antenatal diagnostic test for controlling the spread of thalassemia.

Fasting glucose-to-HbA1c ratio is a good indicator of G6PD deficiency, but not thalassemia, in patients with type 2 diabetes mellitus.

AIMS: Patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency or thalassemia have a shorter red blood cell lifespan; therefore, HbA1c is underestimated in these patients. To address these issues, we sought an early indicator for G6PD deficiency or thalassemia in DM patients. METHODS: A total of 4908 patients with DM and 1848 subjects without DM were included in this study. Fasting glucose (FG) levels, HbA1c levels, hemogram profiles and G6PD activities were measured. Genotypic analyses of G6PD deficiency and thalassemia were performed. RESULTS: DM patients with G6PD deficiency had significantly higher FG/HbA1c ratios than did those without G6PD deficiency (26.54 vs. 18.36; p < 0.0001). We divided the FG level into four categories: ≤150, 151-250, 251-350, and ≥351 mg/dL. Among all groups, only patients with DM and G6PD deficiency had higher FG/HbA1c ratios than those of patients with DM alone or DM with thalassemia. To evaluate the reliability of the FG/HbA1c ratio, receiver operating characteristic analyses were performed. The areas under the curve for detecting FG ≤ 150, 151-250, 251-350, and ≥351 mg/dL with G6PD deficiency based on the FG/HbA1c ratio were 0.839 (p < 0.001), 0.888 (p < 0.001), 0.891 (p < 0.001), and 0.640 (p = 0.3954), respectively. G6PD deficiency was confirmed by genetic analysis. We found common mutations that influenced G6PD activity and HbA1c levels. CONCLUSIONS: The FG/HbA1c ratio is a good indicator of DM with G6PD deficiency. If this ratio is determined to be high in a clinical setting, then the clinician must consider whether the patient has a G6PD deficiency, and HbA1c reference values must be adjusted to avoid misdiagnosis and incorrect treatment decisions.

Recombinant ORF66 and ORFK12 antigens for the detection of human herpesvirus 8 antibodies in HIV-positive and -negative patients.

Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma (KS)-associated herpesvirus (KSHV), is not routinely isolated in cell cultures, and thus detection of HHV-8-specific antibodies is usually performed. In this study, we performed recombinant antigens ORF66- and ORFK12-based Western blot strip assays and ELISA, and surveyed the seroprevalence of HHV-8 antibodies in HIV-positive and -negative patients. In serum samples from patients with positive plasma HHV-8 DNA, the sensitivity of the Western blot strip assay was 100% for the anti-ORF66 antibodies and 83.3% for the anti-ORFK12 antibodies. In addition, ORF66-based ELISA showed higher levels of specificity (87.3%) and sensitivity (84.8%) than ORFK12-based ELISA. Moreover, the area under the receiver-operating characteristics curves (AUROC) was 0.76 for ORF66-based ELISA and 0.66 for ORFK12-based ELISA. The seroprevalence of HHV-8 antibodies to ORF66 and/or ORFK12 in the HIV-infected patients (55%, 97/176) was significantly higher than in the DM patients (45%, 135/301) (P = 0.03) and the HIV-/DM-negative group (11%, 11/100) (P < 0.01). In the HIV-infected patients, the seropositivity of the HHV-8-specific antibody was 30% to both antigens, 19% to ORFK12 and 5.7% to ORF66. Importantly, HHV-8 seropositivity in the HIV-infected patients was significantly associated with the transmission method of intravenous injection and high levels of HIV RNA loading (P < 0.01), but not with gender, CD4 cell numbers or AIDS symptoms. This study assessed the sensitivity and specificity of ORF66 and ORFK12 for the detection of HHV-8 antibodies, providing novel antigens for the diagnosis of HHV-8 infection and epidemiology of HHV-8 seroprevalence.

Genotyping, plasmid analysis, and antimicrobial susceptibility of Salmonella enterica serotype Enteritidis isolates from humans and chickens in central Taiwan.

BACKGROUND/PURPOSE: Salmonella enterica serotype Enteritidis (SE) is the most frequent etiological agent of human salmonellosis. The molecular epidemiology and antimicrobial susceptibility of human and chicken isolates of SE were examined. METHODS: A total of 27 human and 40 chicken isolates of SE were collected in 2005-2006. We examined these isolates by antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE), and plasmid analysis. RESULTS: Most isolates were susceptible to the seven antibiotics tested, except chicken isolates in 2005, which showed 70% resistance to streptomycin and 75% to tetracycline. There were six plasmid profiles identified among these isolates. Almost all isolates (97%) harbored the 60-kb serotype-specific virulence plasmid. PFGE using XbaI digestion separated human isolates into eight subtypes (1a-1h) and chicken isolates into four subtypes (1a-1c and 1g). In 2005, 1a and 1c were predominant for human isolates and 1a for chicken isolates. However, in 2006, 1a and 1c remained predominant for human isolates and 1b and 1c for chicken isolates. Most 1b and 1c isolates belonged to plasmid type 2 or 4. Correlation between plasmid patterns and PFGE subtypes was obtained between a 36-kb plasmid and 1b and between another 3.6-kb plasmid and 1a. CONCLUSION: Plasmid profiling and PFGE were efficient for discriminating SE isolates from different sources. Our data support the notion that SE is transmitted from chickens to humans, presumably through the food chain, but it appears that chickens are not the sole reservoir for human infection with SE in Taiwan SE remained susceptible to most antimicrobial agents.

Disturbance of circadian gene expression in endometrial cancer: detection by real-time quantitative RT-PCR.

Circadian genes control the daily changes of the circadian rhythms in a variety of physiological processes, which in turn regulate many functions in the human body. Disruption of circadian rhythms can have a profound influence on our well-being. We established a set of PCR primers and fluorescent probes to analyze the mRNA levels of nine different circadian genes, and used immunohistochemical methods to study four important circadian proteins in 35 endometrial cancers and their paired non-cancerous tissues. Of these, 13 cases showed reduced expression in all nine circadian genes in the cancerous tissues relative to the paired non-cancerous tissues; the remaining cases showed similar reduced expression in 4-8 of the genes analyzed. Conversely, 3 non-cancerous tissues showed reduced expression in all nine circadian genes in comparison with their respective adjacent cancerous tissues, whereas 6 other non-cancerous tissues showed reduced expression in 6-8 of the circadian genes. These results were also confirmed by immunohistochemical study. Expression of the circadian genes is perturbed in endometrial cancer. Based on these results, we suggest that different circadian rhythms occur in endometrial cancer and non-cancerous tissues. Our results may provide the molecular basis for chronotherapy of endometrial cancer.

Lewis blood genotypes of peptic ulcer and gastric cancer patients in Taiwan.

AIM: The Lewis b (Le(b)) antigen has been implicated as a possible binding site for attachment of Helicobacter pylori (H pylori) to gastric mucosa. However, studies both supporting and denying this association have been reported in the literature. Differences in secretor (Se) genotype have been suggested as a possible reason for previous discrepancies. Therefore, we investigated the relationship between Le and Se genotypes and H pylori infection rates in people with peptic ulcer or gastric cancer. METHODS: Peripheral blood samples were obtained from 347 patients with endoscopic evidence of peptic ulcer disease (235 cases of duodenal ulcer, 62 of gastric ulcer, and 50 of combined duodenal ulcer/ gastric ulcer) and 51 patients with gastric cancer on endoscopy. Peripheral blood specimens from 101 unrelated normal volunteers were used as controls. Lewis phenotype was determined using an antibody method, whereas Le and Se genotypes were determined by DNA amplification and restriction enzyme analysis. Gastric or duodenal biopsies taken from patients with endoscopic evidence of peptic ulcer or gastric cancer were cultured for H pylori. Isolates were identified as H pylori by morphology and production of urease and catalase. The H pylori infection status was also evaluated by rapid urease test (CLO test), and urea breath test ((13)C-UBT). Results of studies were analyzed by chi-square test (taken as significant). RESULTS: H pylori was isolated from 83.7% (303/347) of patients with peptic ulcer disease. Statistical analysis did not show any significant difference in Lewis phenotype or genotype between patients with and without H pylori infection. No significant association was found between Lewis genotype and peptic ulcer or gastric cancer. CONCLUSION: Lewis blood genotype or phenotype may not play a role in the pathogenesis of H pylori infection. However, bacterial strain differences and the presence of more than one attachment mechanism may limit the value of epidemiological studies in elucidating this matter.

Applicability of adipose-derived stem cells in type 1 diabetes mellitus.

Type 1 diabetes mellitus (T1DM) is a form of early onset diabetes mellitus characterized by the autoimmune destruction of insulin-producing cells (IPCs), resulting in hyperglycemia and abnormal glucose metabolism. There are currently no treatments available capable of completely curing the symptoms associated with the loss or functional defects of IPCs. Nonetheless, stem cell therapy has demonstrated considerable promise in the replacement of IPCs with immunomodulatory functions to overcome the defects caused by T1DM. Adipose-derived stem cells (ADSCs) are particularly suitable for use in cell transplantation therapy, especially when seeking to avoid the ethical issues and tumorigenic complications commonly associated with embryos or induced pluripotent stem cells. Cell-based treatments have demonstrated therapeutic advantages and clinical applicability of ADSCs in T1DM, ensuring their suitability for transplantation therapy. This manuscript focuses on the benefits and possible mechanisms in a T1DM-relevant model and displays positive results from finished or ongoing human clinical trials. We also discuss and hypothesize potential methods to further enhance the therapeutic efficacy of these efforts, such as a humanized rodent model and gene therapies for IPC clusters, to meet the clinical applicability of the standard.

Molecular analysis of thiopurine S-methyltransferase alleles in South-east Asian populations.

Thiopurine S-methyltransferase (TPMT) catalyses the S-methylation of thiopurine drugs. In Caucasians, four variant TPMT alleles have been detected in over 80% of individuals with low or intermediate TPMT activity. The wild-type allele is designated as TPMT*1 and the mutant alleles are designated TPMT*2 through TPMT*8. The frequency of these alleles in different ethnic groups has not been well defined. In this study, one hundred individuals, from each of the Indonesian, Thai and Philippine populations, together with 249 Taiwanese, were analysed by polymerase chain reaction-restriction fragment length polymorphism and direct sequencing methods. The results showed that the allelic frequencies of TPMT*3C were 0.6% for Taiwanese and 1% for Filipino, Thai and Indonesian populations, respectively. One Filipino with a Caucasian parent was found to be heterozygous for the TPMT*2 allele. This study provides the first analysis of the allele frequency distribution of all known TPMT mutations in South-east Asian populations.

Correlation between protein expression and epigenetic and mutation changes of Wnt pathway-related genes in oral cancer.

The components of the Wnt-signaling pathway are reported to be mutated in human cancer cells, but the relationship between the components and oral squamous carcinoma (SCC) is still unknown. In this study, we analyzed the epigenetic changes and expression patterns of four member proteins of the Wnt-signaling pathway and analyzed the mutations of beta-catenin and AXIN 1 genes, in order to explore the roles of the pathway in the development of oral cancer. The results showed that there are no beta-catenin and AXIN 1 gene mutations and no methylation of the CpG island of beta-catenin, AXIN I and GSK3beta genes in oral cancer cells; methylation of the CpG island of APC occurs in the precancerous stage and it is a dynamic change; the aberrant expressions or abnormal localization of the Wnt-signaling pathway proteins have no relationship with methylation status or mutation. From our results, we suggest that the Wnt pathway related genes play a very limited role in the development of oral SCC.

Epigenetic changes of tumor suppressor genes, P15, P16, VHL and P53 in oral cancer.

We performed methylation specific PCR to explore the mechanism of inactivation of tumor suppressor genes P15, P16, P53 and VHL in 48 oral SCC. The frequencies of aberrant methylation on the promoter of the P15, the P16, the P53 and the VHL genes were 0.27 (13/48), 0.42 (20/48), 0.04 (2/48) and none, respectively. Altogether, over 50% of the samples showed the CpG-island methylation modification in at least one of the three tumor suppressor genes, indicating that the frequent inactivation of these genes may be an important step during oral cancer development, and the methylation inactivation of P15 or P16 may occur at pre-cancerous stage.

Molecular basis for the RhD negative phenotype in Chinese.

RhD negative individuals are rare and only account for 0.3-0.5% of Taiwanese population. There are some variations among Chinese RhD negative individuals and the molecular basis of these variants is unknown. Two hundred and four RhD negative DNA samples were investigated by a modified polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) and RT-PCR. Several representative cases were further studied using Southern blot analysis. Three types of genetic change in RhD negative individuals were discovered in the Taiwanese population. The most common one, accounting for 150 (73.5%) of 204 cases, was a deletion of the D gene with expression of normal ce or cE antigens (72.5% ce, and 1.0% cE), which were produced by the ce or cE allele of the RHCE gene. The second one, Del, was a deletion of 1013 bp between introns 8 and 9 including exon 9 of the RHD gene. This type accounted for 41 (20.1%) of 204 D negative individuals. The third type was caused by genomic rearrangement around intron 2 and intron 9 between the RHD and RHCE genes and it results in a hybrid gene (D-CE-D) with exons 1, 2 and 10 belonging to the RHD gene. This type of recombination accounted for 13 (6.4%) of 204 D negative individuals. The RhD negative variants found in this study are combination of two of the three alleles, described above. The PCR methods, which detect the differences in introns 1, 2 and 4 or exon 7 for differentiating D positive and D negative, are not reliable methods for studies in the Chinese population.

The correlation between CpG methylation and protein expression of P16 in oral squamous cell carcinomas.

We examined the P16 expression by immunohistochemical stain and detected the methylation by methylation specific polymerase chain reaction (MSP) in 48 primary oral squamous cell carcinoma (SCC) tissues. The results showed that 20/48 (41.7%) of cancerous tissues had CpG methylation around the promoter region, but 8/48 (17%) of the nearby non-cancerous tissues also had CpG methylation, around the promoter region. The results from immunohistochemical studies showed that reduced and heterogeneous expression of P16 were found in the tissues, which had CpG methylation around the promoter region. In conclusion, the methylation of P16 in oral SCC occurs in pre-cancerous and cancerous stage, which results in decreasing or abolishing the P16 expression, which is heterogeneous in the cancer cells.

Sulfotransferase 1A2*2 is a risk factor for early-onset breast cancer.

The estrogen-signaling pathway plays an important role in the pathophysiology of breast cancer, and the sulfotransferase 1A (SULT1A) family has been found to be both downstream targets of tamoxifen and a risk factor of breast cancer. We have used PCR-RFLP and direct sequencing methods to determine SULT1A2 polymorphisms in 230 Taiwanese breast cancer patients. The results showed that the frequencies of SULT1A2*1 and SULT1A2*2 occurring were 94.8% and 5.2%, respectively. No SULT1A2*3 allele was found in these patients. In comparison with the frequency of healthy controls (96.0% and 4.0% for SULT1A2*1 and SULT1A2*2, respectively), the allelic frequencies of SULT1A2 polymorphisms in these patients were not statistically significant (p=0.398). However, the SULT1A2*2 allele seems to influence the age of onset among early-onset breast cancer patients (p=0.021, OR=2.74, 95%CI=1.13-6.65).

The correlation between CpG methylation on promoter and protein expression of E-cadherin in oral squamous cell carcinoma.

BACKGROUND: Reduction of E-cadherin in most common epithelial tumors relates to metastasis, which results from the silence of E-cadherin by CpG methylation. MATERIALS AND METHODS: We examined the E-cadherin expression by immunohistochemical staining and detected methylation by methylation-specific polymerase chain reaction (MSP) in 48 primary oral SCC tissues. RESULTS: The results showed that 41 out of 48 (85.4%) cancerous tissues and 16 out of 48 (33.3%) nearby non-cancerous tissues had CpG methylation on the promoter region of E-cadherin. In these non-cancerous tissues, 2 out of 16 (12.5%) had no methylation change in their paired cancerous part. Immunohistochemical study showed that a decreased expression pattern was found in the tissue which had CpG methylation on the promoter region, but an over expression island or aberrant expression was also frequently found in these cases. CONCLUSION: The methylation of E-cadherin in oral SCC may occur in the precancerous stage and the process is dynamic, which has no relationship with the aberrant expression of E-cadherin protein.

Red blood cell alloimmunisation among Chinese patients with ß-thalassaemia major in Taiwan.

BACKGROUND: The development of red blood cell (RBC) antibodies can significantly complicate transfusion therapy in transfusion-dependent patients with thalassaemia. However, few data are available on the frequency of RBC alloimmunisation in the Chinese population with ß-thalassaemia major. MATERIALS AND METHODS: In this retrospective study, we investigated the development of RBC antibodies among Chinese patients with ß-thalassaemia major who had received long-term transfusion therapy with leucodepleted blood in our hospital over a period of 20 years. RESULTS: Of the 64 patients studied, six (9.4%) developed RBC alloantibodies, including four anti-E, one anti-C and one anti-"Mi(a)". All of the six alloimmunised patients had experienced previous transfusion reactions, while only 12 of the 58 non-immunised patients had had previous transfusion reactions (100% vs 15.5%; p <0.001). After subsequent transfusions with RBC which were negative for the antigens for the corresponding alloantibodies, all the RBC alloantibodies became undetectable within 1 year without additional interventions to eliminate them. CONCLUSIONS: RBC alloantibodies in Chinese patients with ß-thalassaemia major in Taiwan were different from those in other populations. The development of RBC alloantibodies was associated with previous transfusion reactions. Additional treatment may not be necessary for patients with alloantibodies.

Evaluation of breast cancer susceptibility loci on 2q35, 3p24, 17q23 and FGFR2 genes in Taiwanese women with breast cancer.

AIM: Breast cancer is the most common cancer in women. In recent years, mounting evidence has identified the possibility that 2q35, 3p24, 17q23 and fibroblast growth factor receptor 2 (FGFR2) may be genetic susceptibility loci for breast cancer. This study aimed to evaluate the association of four polymorphic genotypes in these loci with breast cancer in Taiwanese women. PATIENTS AND METHODS: Eighty-eight patients with breast cancer and 70 controls without breast cancer were selected. Polymorphic variants of 2q35-rs13387042, 3p24-rs4973768, 17q23-rs650490 and FGFR2-rs2981578 were analyzed to test for their association with breast cancer susceptibility. The 2q35, 17q23 and FGFR2 polymorphisms were detected using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) and the 3p24 polymorphism was detected using an amplification-created restriction site method. RESULTS: The distribution of genotypes of 2q35 were significantly different between the breast cancer group and the control group (p=0.035), while the distributions for 3p24, 17q23, and FGFR2 did not produce statistically significant differences (p>0.05). In addition, allele A of 2q35 conferred a higher risk for breast cancer risk than allele G (odds ratio, OR=2.95, 95% confidence interval, CI=1.29-6.71, p=0.008). Furthermore, the genotypic distribution of 2q35 was not significantly different among patients with different tumor stages, or from different specimen type. CONCLUSION: The 2q35 allele A may be a potential biomarker for breast cancer risk, but further confirmation is required to determine its role in breast carcinogenesis. Blood samples can be used for determining the genotypes for 2q35-rs13387042 in patients for risk of breast cancer.

Multilocus sequence typing of invasive group B Streptococcus in central area of Taiwan.

BACKGROUND: Group B Streptococcus (GBS) (Streptococcus agalactiae) is an important pathogen in neonates, pregnant women, and adults with underlying disease. METHODS: Fifty clinical isolates were collected during the period 2001-2004 and analyzed by multilocus sequence typing and capsular serotyping. RESULTS: The six major sequence types (STs) identified by multilocus sequence typing were ST1, ST12, ST19, ST17, ST23, and ST10. Five major clonal complexes (CCs) and one single ST (ST61) from 11 different STs were found. CC1 (n=14) was the most common one, followed by CC12 (n=13), CC19 (n=9), CC17 (n=7), and CC23 (n=6). The most common serotypes were serotype III, followed by Ib, V, Ia, and IV. The most invasive strains in adults belonged to ST1 (CC1) and serotype V, and those in neonates belonged to ST17 (CC17) and serotype III. In addition, ST19 was distributed in adults and neonates. CONCLUSIONS: These results are similar to those of previous reports, but some geographic differences were found, suggesting that limited clonal lineages play important roles in GBS-associated diseases worldwide. Continued tracking of GBS in the population through clinical isolates is important for epidemiologic investigations and vaccine development.

Sodium bicarbonate supplementation prevents skilled tennis performance decline after a simulated match.

The supplementation of sodium bicarbonate (NaHCO3) could increase performance or delay fatigue in intermittent high-intensity exercise. Prolonged tennis matches result in fatigue, which impairs skilled performance. The aim of this study was to investigate the effect of NaHCO3 supplementation on skilled tennis performance after a simulated match. Nine male college tennis players were recruited for this randomized cross-over, placebo-controlled, double-blind study. The participants consumed NaHCO3 (0.3 g. kg-1) or NaCl (0.209 g. kg-1) before the trial. An additional supplementation of 0.1 g. kg-1 NaHCO3 or 0.07 g. kg-1 NaCl was ingested after the third game in the simulated match. The Loughborough Tennis Skill Test was performed before and after the simulated match. Post-match [HCO3-] and base excess were significantly higher in the bicarbonate trial than those in the placebo trial. Blood [lactate] was significantly increased in the placebo (pre: 1.22 ± 0.54; post: 2.17 ± 1.46 mM) and bicarbonate (pre: 1.23 ± 0.41; post: 3.21 ± 1.89 mM) trials. The match-induced change in blood [lactate] was significantly higher in the bicarbonate trial. Blood pH remained unchanged in the placebo trial (pre: 7.37 ± 0.32; post: 7.37 ± 0.14) but was significantly increased in the bicarbonate trial (pre: 7.37 ± 0.26; post: 7.45 ± 0.63), indicating a more alkaline environment. The service and forehand ground stroke consistency scores were declined significantly after the simulated match in the placebo trial, while they were maintained in the bicarbonate trial. The match-induced declines in the consistency scores were significantly larger in the placebo trial than those in the bicarbonate trial. This study suggested that NaHCO3 supplementation could prevent the decline in skilled tennis performance after a simulated match.