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Background Evidence for mitigation of transfusion-transmitted dengue informed by surveillance data is lacking. In this study, we evaluated the risk of positive dengue viral (DENV) ribonucleic acid (RNA) from blood transfusions during a large outbreak in Taiwan. Methods Serum collected from blood donors living in districts experiencing the dengue epidemic were tested for DENV RNA using a qualitative transcription-mediated nucleic acid amplification assay (TMA). The TMA-reactive specimens were further tested for immunoglobulin (Ig)M and IgG antibodies, nonstructural protein 1 (NS1) antigen, and viral RNA by reverse-transcription polymerase chain reaction. We estimated DENV RNA prevalence and the number of DENV infections among blood donors. Results A total of 4976 specimens were tested for DENV RNA, and 21 were TMA-reactive. The detection rate was 0.84 (95% confidence interval [CI], 0.15–4.73), 3.36 (95% CI, 1.31–8.60), and 6.19 (95% CI, 3.14–12.17) per 1000 donors in districts where the weekly dengue incidence was 5–50, 50–200, and 200 or more per 100 000 residents, respectively. Alanine aminotransferase screening only detected 4.4% of TMA-reactive donations. A total of 143 transfusion-transmitted DENV infections probably occurred during this outbreak, accounting for 9.2 in 10 000 dengue infections. Conclusions Approximately 0.5%–1% of blood donations were DENV RNA positive in epidemic districts. The correlation of DENV RNA rates with dengue incidence may inform the design of effective control measures.

The prevalence of hepatitis C virus (HCV) infection in Taiwan was approximately 4% a decade ago, much higher than the worldwide average. This study aimed to assess the HCV burden among 4 million voluntary blood donors after 2 decades of prevention and treatment policies. We retrieved screening results for anti‐HCV and HCV RNA from the Database for Evaluating Voluntary Taiwanese Eligible Donors. First‐time blood donors who donated blood after 1999 and repeat donors who donated blood more than once between 2013 and 2017 were included to estimate HCV prevalence and incidence, respectively. The Cox proportional hazards model was used to estimate hazard ratios. Geographic variation in HCV prevalence and incidence in 364 townships was also analyzed. The prevalence study included 3,656,598 first‐time donors. The overall crude prevalence of anti‐HCV decreased from 15.5 to 4.5 per 1,000 donors between 1999 and 2017. Younger birth cohorts had a significantly lower prevalence of anti‐HCV. The majority of townships (64.3%) in Taiwan showed a significantly decreased prevalence. The incidence study included 1,393,014 repeat donors followed for 3,436,607 person‐years. Ninety‐eight donors seroconverted to HCV RNA positivity, resulting in an HCV incidence of 2.9 per 100,000 person‐years. Donors living in townships where HCV RNA prevalence was greater than 2 per 1,000 had at least 2.5‐fold greater risk of new HCV infection. Conclusion: HCV prevalence in Taiwanese first‐time blood donors decreased by 71% in the last 2 decades. However, townships with higher HCV prevalence also showed higher HCV incidence and require more active intervention., HCV prevalence and incidence were estimated among four million blood donors in Taiwan. The overall crude prevalence of anti‐HCV decreased by 71% during 1999‐2017, and incidence of HCV RNA was as low as 2.85 per 100,000 in recent years. This successful control may be due to the overall improvements in medical resources, practices, and health education.

Due to excessive clinical blood usage and a rapidly aging population, an impending blood shortage in Taiwan is inevitable. This study aimed to determine the potential blood deficit in Taiwan in 2030. The numbers of units of whole blood (WB) donated and red blood cells (RBC) transfused will increase from 1,182,973 to 1,115,803 in 2018 to 1,230,500 and 1,250,760 in 2030, respectively. Considering the gap between donation and transfusion, we estimate a deficit of 97,633 units of WB in 2030. Blood collection will increasingly rely on donors over the age of 40. Moreover, we observed a large decline in units of WB donated among people less than 25 years old. A growing demand for RBC is attributed to the aging population and limited decreases in age-specific units of RBC transfused per capita. Scrutinizing and forecasting changes in blood collection and transfusion are necessary for generating strategies to mitigate blood shortages.

Glycophorin hybrids such as GP.Mur are common in Southeast Asians. In Taiwan, clinically significant alloantibodies to the GP.Mur phenotype are the most important issue in blood banks. A large-scale screening of glycophorin hybrids in the Taiwanese population is urgently needed to ensure transfusion safety. Four clones of human hybridomas that secrete anti-Mia, anti-MUT, and anti-Mur were established by fusing human B-lymphocytes and myeloma cells (JMS-3). The specificity of each monoclonal antibody (MoAb) was characterized. Three MoAbs were applied on an Automated Pretransfusion Blood Testing Analyzer (PK7300/PK7400) for donor screening. Genotyping was performed to determine the detailed subgrouping of glycophorin hybrids. Four MoAbs are IgM antibodies. Anti-Mia (377T) binds to 46DXHKRDTYA54, 48HKRDTYAAHT57 peptides, and anti-Mia (367T) binds to 43QTNDXHKRD51 peptides (X indicates T, M, or K). Anti-Mur is reactive with 49KRDTYPAHTA58 peptides. Anti-MUT is reactive with 47KHKRDTYA54. A total of 78,327 donors were screened using three MoAbs, and 3690 (4.71%) were GP.Mur, 20 (0.025%) were GP.Hut, and 18 (0.022%) were GP.Vw. When the Mia antigen was introduced as routine screening, the frequency of Mi(a+) among blood donors in Taiwan was 4.66% (67,348/1,444,541). Mia antigen was implemented as a routine blood testing, and the results were labeled on all red blood cell (RBC) units.

Objective - This study examines the relationship between perceived stress, athletic burnout and leisure amongst badminton players. Methodology/Technique - The research subjects were all first national ranking tournament badminton players in 2012. The study uses convenience sampling to conduct a questionnaire survey. 350 questionnaires were distrubuted, with 288 valid questionnaires being returned (male 195, female 93). The rate of effectiveness was 82%. All of the data collected was analyzed using descriptive statistic and hierarchical regression analysis. Findings – The research subjects were all first national ranking tournament badminton players in 2012. The study uses convenience sampling to conduct a questionnaire survey. 350 questionnaires were distrubuted, with 288 valid questionnaires being returned (male 195, female 93). The rate of effectiveness was 82%. All of the data collected was analyzed using descriptive statistic and hierarchical regression analysis. Novelty – The study highlights that badminton players who participate in leisure-based activities are able to effectively adjust their perception of pressure to a "reduced sense of accomplishment" which has an effect on athletic burnout. Additionally, the study results give rise to variety of proposed solutions or suggestions for dealing with burnout or stress. Type of Paper - Empirical Keywords: Hierarchical Regression Analysis; Sources of Stress; Leisure; Badminton Players. JEL Classification: M10, Z20.

Background An attenuated mutant (designated NY303) of Vibrio vulnificus, which causes serious wound infection and septicemia in humans, was isolated fortuitously from a clinical strain YJ016. This mutant was defective in cytotoxicity, migration on soft agar and virulence in the mouse. The purpose of this study was to map the mutation in this attenuated mutant and further explore how the gene thus identified is involved in virulence. Methods The whole genome sequence of mutant NY303 determined by next-generation sequencing was compared with that of strain YJ016 to map the mutations. By isolating and characterizing the specific gene-knockout mutants, the gene associated with the phenotype of mutant NY303 was identified. This gene encodes a global regulator, Lrp. A mutant, YH01, deficient in Lrp was isolated and examined in vitro, in vivo and ex vivo to find the affected virulence mechanisms. The target genes of Lrp were further identified by comparing the transcriptomes, which were determined by RNA-seq, of strain YJ016 and mutant YH01. The promoters bound by Lrp were identified by genome footprinting-sequencing, and those related with virulence were further examined by electrophoretic mobility shift assay. Results A mutation in lrp was shown to be associated with the reduced cytotoxicity, chemotaxis and virulence of mutant NY303. Mutant YH01 exhibited a phenotype resembling that of mutant NY303, and was defective in colonization in the mouse and growth in mouse serum, but not the antiphagocytosis ability. 596 and 95 genes were down- and up-regulated, respectively, in mutant YH01. Many of the genes involved in secretion of the MARTX cytotoxin, chemotaxis and iron-acquisition were down-regulated in mutant YH01. The lrp gene, which was shown to be negatively autoregulated, and 7 down-regulated virulence-associated genes were bound by Lrp in their promoters. A 14-bp consensus sequence, mkCrTTkwAyTsTG, putatively recognized by Lrp was identified in the promoters of these genes. Conclusions Lrp is a global regulator involved in regulation of cytotoxicity, chemotaxis and iron-acquisition in V. vulnificus. Down-regulation of many of the genes associated with these properties may be responsible, at least partly, for loss of virulence in mutant NY303. Electronic supplementary material The online version of this article (doi:10.1186/s12929-017-0361-9) contains supplementary material, which is available to authorized users.

The distribution of Lrp target genes in different functional categories. (DOCX 334Â kb)

Location of point mutation in lrp of V. vulnificus mutant NY303. (DOCX 72Â kb)

The mRNA levels of genes predicted to be involved in iron-acquisition and chemotaxis in the wild-type strain and Î lrp mutant. (DOCX 219Â kb)

Phagocytosis of various V. vulnificus strains by RAW 264.7 cells after mixed infection. (DOCX 55Â kb)

The mRNA levels of lrp in the wild-type strain incubated in various media. (DOCX 158Â kb)

Polymorphism of human platelet antigens (HPAs) leads to alloimmunizations and immune-mediated platelet disorders including fetal-neonatal alloimmune thrombocytopenia (FNAIT), posttransfusion purpura (PTP), and platelet transfusion refractoriness (PTR). HPA typing and knowledge of antigen frequency in a population are important in particular for the provision of HPA-matched blood components for patients with PTR. We have performed allele genotyping for HPA-1 through -6 and -15 among 998 platelet donors from 6 blood centers in Taiwan using sequence-specific primer polymerase chain reaction. The HPA allele frequency was 99.55, and 0.45% for HPA-1a and -1b; 96.49, and 3.51% for HPA-2a and -2b; 55.81, and 44.19% for HPA-3a and -3b; 99.75, and 0.25% for HPA-4a and -4b; 98.50, and 1.50% for HPA-5a and -5b; 97.75 and 2.25% for HPA-6a and -6b; 53.71 and 46.29% for HPA-15a and -15b. HPA-15b and HPA-3a, may be considered the most important, followed by HPA-2, -6, -1, -5, and -4 systems, as a cause of FNAIT, PTP, and PTR based on allele frequency. HPA-4b and HPA-5b role cannot be excluded based on their immunogenicity. A larger-scale study will now be conducted to confirm these hypotheses and to establish an apheresis donor database for the procurement of HPA-matched apheresis platelets for patients with PTR.

Almost all of the studies described elderly as beginning at the age 70 and very few focused on the group of patients over 80 years of age. This study was undertaken to compare the surgical risk and prognosis between septuagenarians and octogenarians undergoing pancreaticoduodenectomy and to clarify whether or not pancreaticoduodenectomy is justified in octogenarians.Among 276 patients with periampullary lesions undergoing pancreaticoduodenectomy between 1982 and 2000, octogenarians and septuagenarians were identified. The study concentrated on the surgical risks and outcomes.There were 16 (6%) octogenarians and 82 (30%) septuagenarians among our 276 patients undergoing pancreaticoduodenectomy. Surgical mortality did not significantly increase in octogenarians (13%), as compared to septuagenarians (12%). Surgical morbidity was also similar in both groups (51% in octogenarians vs. 56% in septuagenarians). Octogenarians needed more frequent care in the intensive care unit (69%) postoperatively than septuagenarians (27%), p = 0.001. There was no significant difference in survival, (median survival = 16 months for septuagenarians and 17.6 months for octogenarians), p = 0.137. About half of each group (44.2% septuagenarians and 54.5% octogenarians) still died of the underlying periampullary lesions, p = 0.771.Surgical risk did not significantly increase and prognosis was similar in octogenarians after pancreaticoduodenectomy, as compared to septuagenarians. Therefore, pancreaticoduodenectomy is justified not only in septuagenarians but also in octogenarians if carefully selected.

Territrem B (TRB) is a fungal metabolite isolated from Aspergillus terreus shown previously to be a potent and irreversible inhibitor of acetylcholinesterase (AChE). In the present study, a number of binding and inhibition assays were carried out to further characterize the inhibitory effect of TRB. The results indicate that the binding of TRB (a) is much more selective than a well characterized selective inhibitor of AChE, BW284C51, (b) adopts a one-to-one stoichiometry with the enzyme, (c) cannot be undone by an AChE-regenerating oxime agent, which contrasts the ability of 8 M urea to release AChE-bound TRB, (d) is enhanced by high concentration NaCl but prevented, unless preincubated, by Triton X-100, and (e) exhibits quasi-first order kinetics with an overall inhibition constant of 0.01 nM(-1) min(-1). Together these results suggest a very different irreversible binding (a noncovalent type) from that of the covalent type, which involves typical irreversible AChE inhibitors such as diisopropylfluorophosphate and neostigmine. According to the prediction of a molecular modeling study, the distinct AChE inhibitory characteristics of TRB may arise from the inhibitor being noncovalently trapped within a unique active-site gorge structure of the enzyme. It was predicted that an optimal TRB. AChE binding would position a narrowing connection of the TRB structure at a constricted area near the entrance of the gorge, thereby providing a structural basis for the observed irreversible binding.

Territrem B (TRB), a fungal metabolite isolated from Aspergillus terreus, potently and noncompetitively inhibited Electrophorus acetylcholinesterase (AChE EC 3.1.1.7), but had no inhibitory effect on horse serum butyrylcholinesterase (BtChE EC 3.1.1.8). The TRB-treated AChE did not recover its enzyme activity after either dialysis or dilution of the inhibited enzyme. The binding of [(14)C]TRB to AChE, but not to BtChE, was demonstrated. The concentrations of territrems required for 50% inhibition of AChE were: TRA 2.4 x 10(-8) M; TRB 1.9 x 10(-8) M; TRC 1.5 x 10(-8) M; TRA' 9.8 x 10(-8) M; TRB' 9.2 x 10(-8) M. Copyright 1996 S. Karger AG, Basel