638 research outputs found
Human papillomavirus infection and anal cytology in Taiwanese homosexual men with and without HIV infection
Introduction: Anal cancer screening has not been adopted by Taiwanese care providers. The study aim was to explore the differences of anal cytology and HPV detection among men with and without HIV.
Methodology: In this case-control study, men with HIV who attended one of the outpatient clinics of Taoyuan General Hospital were enrolled as cases. Men who had experienced condomless sex and tested HIV negative were enrolled as controls. Anal swabs were collected for thin-preparation anal cytology and HPV genotyping.
Results: A total of 288 men who had tested positive for HIV and 208 who had tested HIV negative were enrolled; 75% of subjects with HIV and 30.3% of those without HIV had tested positive for various types of HPV (P < 0.001). Anal cell dysplasia, including atypical squamous cells with undetermined significance (ASCUS), low-grade squamous intraepithelial lesions (LSILs), high-grade squamous intraepithelial lesions (HSILs), or atypical squamous cells cannot exclude HSIL (ASC-H), were noted in 20.8% of men with HIV and 4.8% of those without HIV (P < 0.001). In multivariate analysis, HIV serostatus, history of sexually transmitted infections, having male sexual partners, and practice of anal sex were correlated significantly with detection of any type of HPV. Additionally, both oncogenic and non-oncogenic HPV types were significantly associated with anal cytology dysplasia.
Conclusions: We strongly suggest that there should be awareness of anal HPV infection and related anal cellular dysplasia in at-risk populations
Characteristics of HIV-positive pregnant women and HIV- and antiretroviral therapy-exposed fetuses: A case-control study
Introduction: This study determined risk factors, obstetric comorbidities, and fetal conditions among HIV-positive mothers to improve their maternal care.
Methodology: This retrospective case-control study included HIV-positive pregnant women 18 years of age or older and age-, parity-, and delivery method-matched HIV-negative controls between 2011 and 2018. Those who had stillbirth were excluded. Baseline demographics, labor process, CD4 count, plasma HIV viral load, and antiretroviral therapy (ART) regimen were recorded. Fetal conditions were recorded as well.
Results: Forty HIV-positive women (45 parities; 22 via NSD, 23 via C/S) were included, with 45 HIV-negative parities as controls. Twenty-nine (72.5%) HIV-positive women had illicit drug use. In the HIV-positive group, 17% received ART prior to first perinatal visit, and 75.6% reached viral suppression pre-delivery. Zidovudine and ritonavir-boosted lopinavir were the majorly prescribed ART. Mild perineal lacerations via NSD were observed in HIV-positive women. Fetal body weight was lower in HIV- and ART-exposed fetuses (2665 vs 3010 g, p < 0.001). Preterm delivery PTB (28.9% vs 8.9%, p= 0.015) and small-for gestational age SGA (28.9% vs 8.8%, p = 0.003) rates were higher in the HIV-positive group. There was no vertical transmission of HIV.
Conclusions: HIV-positive women tend to deliver fetuses with low body weight and have higher SGA and PTB rates. Given that most women received zidovudine and protease inhibitors, benefits of newer agents for HIV-positive pregnancies should be studied
Stereotactic ablative radiotherapy versus conventionally fractionated radiotherapy in the treatment of hepatocellular carcinoma with portal vein invasion: a retrospective analysis
BackgroundThis study aimed to compare the clinical outcomes of stereotactic ablative radiotherapy (SABR) and conventionally fractionated radiotherapy (CFRT) in hepatocellular carcinoma (HCC) patients with portal vein invasion (PVI).MethodsHCC patients with PVI treated with radiotherapy from 2007 to 2016 were analysed. CFRT was administered at a median dose of 51.5 Gy (interquartile range, 45-54 Gy) with 1.8-3 Gy per fraction. SABR was administered at a median dose of 45 Gy (interquartile range, 40-48 Gy) with 6-12.5 Gy per fraction. Treatment efficacy, toxicity, and associated predictors were assessed.ResultsAmong the 104 evaluable patients (45 in the SABR group and 59 in the CFRT group), the overall response rate (ORR, complete and partial response) was significantly higher in the SABR group than the CFRT group (62.2% vs. 33.8%, p = 0.003). The 1-year overall survival (OS) rate (34.9% vs. 15.3%, p = 0.012) and in-field progression-free survival (IFPS) rate (69.6% vs. 32.2%, p = 0.007) were also significantly higher in the SABR vs. CFRT group. All 3 rates remained higher in the SABR group after propensity score matching. Multivariable analysis identified SABR and a biologically effective dose ≥65 Gy as favourable predicators of OS. There was no difference between treatment groups in the incidence of radiation-induced liver disease or increase of Child-Pugh score ≥ 2 within 3 months of radiotherapy.ConclusionsSABR was superior to CFRT in terms of ORR, OS, and IFPS. We suggest that SABR should be the preferred technique for HCC patients with PVI
The presence of broadly neutralizing anti-SARS-CoV-2 RBD antibodies elicited by primary series and booster dose of COVID-19 vaccine
Antibody-mediated immunity plays a key role in protection against SARS-CoV-2. We characterized B-cell-derived anti-SARS-CoV-2 RBD antibody repertoires from vaccinated and infected individuals and elucidate the mechanism of action of broadly neutralizing antibodies and dissect antibodies at the epitope level. The breadth and clonality of anti-RBD B cell response varies among individuals. The majority of neutralizing antibody clones lose or exhibit reduced activities against Beta, Delta, and Omicron variants. Nevertheless, a portion of anti-RBD antibody clones that develops after a primary series or booster dose of COVID-19 vaccination exhibit broad neutralization against emerging Omicron BA.2, BA.4, BA.5, BQ.1.1, XBB.1.5 and XBB.1.16 variants. These broadly neutralizing antibodies share genetic features including a conserved usage of the IGHV3-53 and 3–9 genes and recognize three clustered epitopes of the RBD, including epitopes that partially overlap the classically defined set identified early in the pandemic. The Fab-RBD crystal and Fab-Spike complex structures corroborate the epitope grouping of antibodies and reveal the detailed binding mode of broadly neutralizing antibodies. Structure-guided mutagenesis improves binding and neutralization potency of antibody with Omicron variants via a single amino-substitution. Together, these results provide an immunological basis for partial protection against severe COVID-19 by the ancestral strain-based vaccine and indicate guidance for next generation monoclonal antibody development and vaccine design
Studies on Ancient Rice—Where Botanists, Agronomists, Archeologists, Linguists, and Ethnologists Meet
Abstract
Taiwan’s aboriginal peoples are thought to be related to ancestral Austronesian-speaking peoples. Currently, Taiwan has 14 officially acknowledged aboriginal tribes. The major crops currently farmed in aboriginal areas are rice (Oryza sativa) and foxtail millet (Setaria italica). Archeologists recently excavated the remains of several early cultures in Taiwan. The most plentiful plant remains were carbonated rice and foxtail millet grains. The earliest 14C date of these excavation sites is ∼5,000 bp. These settlements may be those of the earliest ancestral Austronesian speakers in Taiwan. Rice domestication is a complex story. In this study, we identified the functional nucleotide polymorphisms of 16 domestication-related genes using 60 landraces collected from aboriginal Taiwanese villages about 100 years ago. We also screened the phenotypes of these landraces. By integrating pheno- and genotypic data, together with data from archeologists and linguists, we may be able to better understand the history of rice cultivation in Taiwan and nearby areas.</jats:p
Clonal dissemination of the multi-drug resistant Salmonella enterica serovar Braenderup, but not the serovar Bareilly, of prevalent serogroup C1 Salmonella from Taiwan
<p>Abstract</p> <p>Background</p> <p>Nontyphoidal <it>Salmonella </it>is the main cause of human salmonellosis. In order to study the prevalent serogroups and serovars of clinical isolates in Taiwan, 8931 <it>Salmonellae </it>isolates were collected from 19 medical centers and district hospitals throughout the country from 2004 to 2007. The pulsed-field eletrophoresis types (PFGE) and antibiotic resistance profiles of <it>Salmonella enterica </it>serovars Bareilly (<it>S</it>. Bareilly) and Braenderup (<it>S</it>. Braenderup) were compared, and multi-drug resistance (MDR) plasmids were characterized.</p> <p>Results</p> <p>Over 95% of human salmonellosis in Taiwan was caused by five <it>Salmonella </it>serogroups: B, C1, C2-C3, D1, and E1. <it>S</it>. Typhymurium, <it>S</it>. Enteritidis, <it>S</it>. Stanley and <it>S</it>. Newport were the four most prevalent serovars, accounting for about 64% of isolates. While only one or two major serovars from four of the most prevalent serogroups were represented, four predominant serovars were found in serogroup C1 <it>Salmonellae</it>. The prevalence was decreasing for <it>S</it>. Choleraeuis and <it>S</it>. Braenderup, and S. Virchow and increasing for <it>S</it>. Bareilly. <it>S</it>. Braenderup mainly caused gastroenteritis in children; in contrast, <it>S</it>. Bareiley infected children and elderly people. Both serovars differed by <it>Xba</it>I-PFGE patterns. Almost all <it>S</it>. Bareilly isolates were susceptible to antibiotics of interest, while all lacked plasmids and belonged to one clone. Two distinct major clones in <it>S</it>. Braenderup were cluster A, mainly including MDR isolates with large MDR plasmid from North Taiwan, and cluster B, mainly containing susceptible isolates without R plasmid from South Taiwan. In cluster A, there were two types of conjugative R plasmids with sizes ranging from 75 to 130 kb. Type 1 plasmids consisted of replicons F1A/F1B, <it>bla</it><sub>TEM</sub>, IS<it>26</it>, and a class 1 integron with the genes <it>dfrA12</it>-<it>orfF</it>-<it>aadA2-qacE</it>Δ1-<it>sulI</it>. Type 2 plasmids belonged to incompatibility group Inc<it>I</it>, contained <it>tnpA</it>-<it>bla</it><sub>CMY-2</sub>-<it>blc</it>-<it>sugE </it>genetic structures and lacked both IS<it>26 </it>and class 1 integrons. Although type 2 plasmids showed higher conjugation capability, type 1 plasmids were the predominant plasmid.</p> <p>Conclusions</p> <p>Serogroups B, C1, C2-C3, D1, and E1 of <it>Salmonella </it>caused over 95% of human salmonellosis. Two prevalent serovars within serogroup C1, <it>S</it>. Bareilly and cluster B of S. Braenderup, were clonal and drug-susceptible. However, cluster A of <it>S</it>. Braenderup was MDR and probably derived from susceptible isolates by acquiring one of two distinct conjugative R plasmids.</p
Arginine starvation impairs mitochondrial respiratory function in ASS1-deficient breast cancer cells.
Autophagy is the principal catabolic response to nutrient starvation and is necessary to clear dysfunctional or damaged organelles, but excessive autophagy can be cytotoxic or cytostatic and contributes to cell death. Depending on the abundance of enzymes involved in molecule biosynthesis, cells can be dependent on uptake of exogenous nutrients to provide these molecules. Argininosuccinate synthetase 1 (ASS1) is a key enzyme in arginine biosynthesis, and its abundance is reduced in many solid tumors, making them sensitive to external arginine depletion. We demonstrated that prolonged arginine starvation by exposure to ADI-PEG20 (pegylated arginine deiminase) induced autophagy-dependent death of ASS1-deficient breast cancer cells, because these cells are arginine auxotrophs (dependent on uptake of extracellular arginine). Indeed, these breast cancer cells died in culture when exposed to ADI-PEG20 or cultured in the absence of arginine. Arginine starvation induced mitochondrial oxidative stress, which impaired mitochondrial bioenergetics and integrity. Furthermore, arginine starvation killed breast cancer cells in vivo and in vitro only if they were autophagy-competent. Thus, a key mechanism underlying the lethality induced by prolonged arginine starvation was the cytotoxic autophagy that occurred in response to mitochondrial damage. Last, ASS1 was either low in abundance or absent in more than 60% of 149 random breast cancer biosamples, suggesting that patients with such tumors could be candidates for arginine starvation therapy
Primary tumor site is a useful predictor of cetuximab efficacy in the third-line or salvage treatment of KRAS wild-type (exon 2 non-mutant) metastatic colorectal cancer: a nationwide cohort study
BACKGROUND: Previous studies have shown left-sided colorectal cancer (LCRC) and right-sided colorectal cancer (RCRC) exhibit different molecular and clinicopathological features. We explored the association between the primary tumor site and cetuximab efficacy in KRAS wild-type colorectal cancer (CRC). METHODS: This study enrolled a cohort of patients, who had received cetuximab treatment after two or more lines of chemotherapy for KRAS wild-type (exon 2 nonmutant) metastatic CRC, from the databases of Taiwan Cancer Registry (2004–2010) and National Health Insurance (2004–2011). Survival data were obtained from the National Death Registry. Time to treatment discontinuation (TTD) and overall survival (OS) after the start of cetuximab treatment were compared between patients with LCRC (splenic flexure to rectum) and RCRC (cecum to hepatic flexure). RESULTS: A total of 969 CRC patients were enrolled. Among them, 765 (78.9 %) and 136 (14.0 %) patients had LCRC and RCRC, respectively. Patients with LCRC, compared to patients with RCRC, had longer TTD (median, 4.59 vs. 2.75 months, P = .0005) and OS (median, 12.62 vs. 8.07 months, P < .0001) after the start of cetuximab treatment. Multivariate analysis revealed a right-sided primary tumor site was an independent predictor of shorter TTD (adjusted hazard ratio [HR] = 1.32, using the LCRC group as a reference, 95 % confidence interval: 1.08–1.61, P = .0072) and OS (adjusted HR = 1.45, 95 % CI: 1.18–1.78, P = .0003). CONCLUSION: Our findings demonstrate that a left-sided primary tumor site is a useful predictor of improved cetuximab efficacy in the third-line or salvage treatment of KRAS wild-type (exon 2 nonmutant) metastatic CRC
Rapid establishment of a COVID-19 biobank in NHRI by National Biobank Consortium of Taiwan
By the request of the Minister of Health and Welfare, NHRI Biobank was assigned to
establish a COVID-19 biobank in early Feb, 2020 to collect COVID-19 patients’ blood samples
for Taiwan researchers and industries in an emergent way. It was set up in less than 3 weeks
and quickly opened for application. By August 5, 2020, this COVID-19 biobank has collected
165 blood samples of 110 patients from more than 10 hospitals across north, middle and
south part of Taiwan, including both COVID-19 (þ) and (-) pneumonia patients. This biobank
can provide applicants with biosamples, such as serum, DNA and RNA, and also the clinical
and genomic data, so as to accelerate the COVID-19 treatment and prevention research in
Taiwan. This COID-19 biobank already received 15 applications. It has become the most
important research resource for the COVID-19 pandemic in Taiwan, including new
screening reagents, disease mechanism, the variable human responses and epidemic preventions. Since it is publicly available for both academic and industrial applicants
Structures and therapeutic potential of anti-RBD human monoclonal antibodies against SARS-CoV-2
Background: Administration of potent anti-receptor-binding domain (RBD) monoclonal antibodies has been shown to curtail viral shedding and reduce hospitalization in patients with SARS-CoV-2 infection. However, the structure-function analysis of potent human anti-RBD monoclonal antibodies and its links to the formulation of antibody cocktails remains largely elusive. Methods: Previously, we isolated a panel of neutralizing anti-RBD monoclonal antibodies from convalescent patients and showed their neutralization efficacy in vitro. Here, we elucidate the mechanism of action of antibodies and dissect antibodies at the epitope level, which leads to a formation of a potent antibody cocktail. Results: We found that representative antibodies which target non-overlapping epitopes are effective against wild type virus and recently emerging variants of concern, whilst being encoded by antibody genes with few somatic mutations. Neutralization is associated with the inhibition of binding of viral RBD to ACE2 and possibly of the subsequent fusion process. Structural analysis of representative antibodies, by cryo-electron microscopy and crystallography, reveals that they have some unique aspects that are of potential value while sharing some features in common with previously reported neutralizing monoclonal antibodies. For instance, one has a common VH 3-53 public variable region yet is unusually resilient to mutation at residue 501 of the RBD. We evaluate the in vivo efficacy of an antibody cocktail consisting of two potent non-competing anti-RBD antibodies in a Syrian hamster model. We demonstrate that the cocktail prevents weight loss, reduces lung viral load and attenuates pulmonary inflammation in hamsters in both prophylactic and therapeutic settings. Although neutralization of one of these antibodies is abrogated by the mutations of variant B.1.351, it is also possible to produce a bi-valent cocktail of antibodies both of which are resilient to variants B.1.1.7, B.1.351 and B.1.617.2. Conclusions: These findings support the up-to-date and rational design of an anti-RBD antibody cocktail as a therapeutic candidate against COVID-19.Temple University. College of Science and TechnologyBiolog
- …
