Cell type specific suppression of hyper-recombination by human RAD18 is linked to PCNA K164 ubiquitination.

Homologous recombination (HR) and translesion synthesis (TLS) promote gap-filling DNA synthesis to complete genome replication. One factor involved in both pathways is RAD18, an E3 ubiquitin ligase. Although RAD18's role in promoting TLS through the ubiquitination of PCNA at lysine 164 (K164) is well established, its requirement for HR-based mechanisms is currently less clear. To assess this, we inactivated RAD18 in three human cell lines. Our analyses found that loss of RAD18 in HCT116, but neither hTERT RPE-1 nor DLD1 cell lines, resulted in elevated sister chromatid exchange, gene conversion, and gene targeting, i.e . HCT116 mutants were hyper-recombinogenic (hyper-rec). Loss of RAD18 also impaired TLS activity in HCT116 cells, but unexpectedly, did not reduce clonogenic survival. Interestingly, these phenotypes appear linked to PCNA K164 ubiquitination, as HCT116 PCNA K164R/+ mutants were also hyper-rec and showed reduced TLS activity, consistent with previous studies in rad18 -/- or pcna K164R avian DT40 mutant cells. Importantly, knockdown of UBC9 to prevent PCNA K164 SUMOylation did not affect hyper-recombination, strengthening the link between increased recombination and RAD18-catalyzed PCNA K164 ubiquitination, but not K164 SUMOylation. Taken together, these data suggest that the roles of human RAD18 in directing distinct gap-filling DNA synthesis pathways varies depending on cell type and that these functions are linked to PCNA ubiquitination.

The mediation model of social status on the link between parental attachment, aggressive behavior, and psychological well-being: Evidence from two studies in Vietnamese adolescents and young adults.

Little is known about how insecure attachment affects aggressive behavior and well-being among Vietnamese youth. Using structural equation modeling, we investigate the mediating role of subjective social status (SSS) on the paths from insecure attachment to overt aggressive behavior (OAB) and psychological well-being (PW) in a sample of 1753 Vietnamese adolescents (Mage = 16.136, SD = 0.784) and test whether the results will be replicated in another sample of 601 Vietnamese young adults (Mage = 19.93, SD = 1.35). Participants complete a survey comprising demographic information, attachment styles, SSS, OAB, and PW questionnaires. Our main findings include: (a) anxious attachment positively related to OAB in both samples, (b) anxious attachment was only negatively associated with adolescents' PW, (c) avoidant attachment was positively correlated to OAB in adolescents but negatively correlated in young adults, and (d) avoidant attachment was negatively related to PW in both samples. In addition, (e) in adolescents, the mediation role of SSS was significant in all paths, but (f) SSS only mediated the link from avoidant attachment to PW of young adults. The present study suggests that aggressive behavior might not be associated with social status or attachment in the same way in adolescents compared to young adult Vietnamese samples.

A scalable platform for efficient CRISPR-Cas9 chemical-genetic screens of DNA damage-inducing compounds.

Current approaches to define chemical-genetic interactions (CGIs) in human cell lines are resource-intensive. We designed a scalable chemical-genetic screening platform by generating a DNA damage response (DDR)-focused custom sgRNA library targeting 1011 genes with 3033 sgRNAs. We performed five proof-of-principle compound screens and found that the compounds' known modes-of-action (MoA) were enriched among the compounds' CGIs. These scalable screens recapitulated expected CGIs at a comparable signal-to-noise ratio (SNR) relative to genome-wide screens. Furthermore, time-resolved CGIs, captured by sequencing screens at various time points, suggested an unexpected, late interstrand-crosslinking (ICL) repair pathway response to camptothecin-induced DNA damage. Our approach can facilitate screening compounds at scale with 20-fold fewer resources than commonly used genome-wide libraries and produce biologically informative CGI profiles.

Professional quality of life and its associated factors among Vietnamese doctors and nurses.

BACKGROUND: Prevalence of health workers with occupational health issues ranked fourth among all careers resulting in a reduction in quality of life. However, tools to measure professional quality of life (ProQoL) are unavailable in Vietnamese. This study aims to develop a Vietnamese version of the ProQoL, and examine ProQoL and its associated factors among doctors and nurses. METHODS: The ProQoL is comprised of 30 items measures compassion satisfaction (CS), burnout (BO), and secondary traumatic stress (STS). The tool was translated into Vietnamese following the Guideline by Guillemin et. al (1993), reviewed by expert panels, and validated for internal consistency and test-retest reliability among 38 health workers working at hospitals in HCMC. The validated tool was then used in a cross-sectional study to measure the ProQoL of full-time doctors and nurses working in clinical departments at the University Medical Center, University of Medicine and Pharmacy at Ho Chi Minh City, Vietnam. In addition to the ProQoL, self-reported data about demographic and occupational characteristics were collected. RESULTS: The Vietnamese version of ProQoL achieved high internal consistency (alphas between 0.85 and 0.91) and Intra-class Correlation Coefficients (ICCs between 0.71 and 0.89) for all subscales. Among 316 health workers, mean scores of CS, BO, STS were 36.4 (SD = 5.4), 24.9 (SD = 5.1), 25.9 (SD = 5.3), respectively, indicating moderate levels of CS, BO and STS. Participants who were older (b = 0.17, 95%CI = 0.08, 0.26), had sufficient perceived income (b = 2.59, 95%CI = 0.93, 4.24), and > 10 years of working experience (b = 2.15, 95%CI = 0.68, 3.62), had higher CS scores. Those who were older (b=-0.15, 95%CI=-0.23, -0.07), had sufficient perceived income (b=-2.64, 95%CI=-4.18, -1.09), > 10 years of experience (b=-1.38, 95%CI=-2.76, -0.01), worked in surgical department (b=-1.46, 95%CI=-2.54, -0.38) and 8 hours/day (b=-1.52, 95%CI=-2.61, -0.44), had lower BO scores. Moreover, those in a relationship (b=-2.27, 95%CI=-3.53, -1.01) and had sufficient perceived income (b=-1.98, 95%CI=-3.64, -0.32) had lower STS scores. CONCLUSIONS: The Vietnamese version of ProQoL is valid and reliable for use among Vietnamese health workers. Age, marital status, perceived income status, years of working experience, daily working hours, and specialty was associated with at least one component of ProQoL but gender, religion, education level, and monthly income were not.

High-flow nasal cannula therapy in patients with COVID-19 in intensive care units in a country with limited resources: a single-center experience.

OBJECTIVE: This study was performed to determine the outcomes of patients with coronavirus disease 2019 (COVID-19) who developed hypoxemic respiratory failure necessitating high-flow nasal cannula (HFNC) therapy and to identify the predictors of HFNC therapy success. METHODS: This retrospective observational study involved all patients treated with HFNC therapy at a center for COVID-19 in Viet Nam from August to October 2021. RESULTS: The study recruited 302 patients. Of these 302 patients, 171 (56.6%) underwent successful HFNC therapy, and the all-cause mortality rate was 33.44%. Non-critical COVID-19 and a higher respiratory rate-oxygenation (ROX) index at 48 hours after initiating HFNC therapy were independently correlated with HFNC therapy success. The statistically significant predictors of HFNC therapy success were younger age, non-critical COVID-19, a higher platelet count when starting HFNC therapy, and a higher ROX index at 24, 36, and 48 hours after HFNC therapy initiation. CONCLUSIONS: HFNC therapy appears to be effective in patients with COVID-19 who develop respiratory failure requiring respiratory support. Non-critical COVID-19 and a higher ROX index measured 48 hours after HFNC therapy initiation might serve as predictive factors for the success of HFNC therapy.

Prevalence and impact of myocardial injury among patients hospitalized with COVID-19.

Background: Myocardial injury is a prevalent complication observed in patients hospitalized with COVID-19 and is strongly associated with severe illness and in-hospital mortality. However, the long-term consequences of myocardial injury on clinical outcomes remain poorly understood. This study aimed to assess the impact of myocardial injury on both acute-phase and long-term prognosis in COVID-19 patients. Methods: A retrospective, observational study was conducted on all patients who received treatment at the Intensive Care Center for COVID-19 patient, University Medical Center Ho Chi Minh City (UCICC), from August 3rd, 2021, to October 28th, 2021. Results: A total of 582 patients were enrolled in the study, of which 55.3% were female. The mean age of participants was 63.3 ± 16.2. Out of these patients, 330 cases (56.8%) showed myocardial injury. Compared to patients without myocardial injury, those with myocardial injury were older and had a higher incidence of chronic diseases including hypertension, ischemic heart disease, atrial fibrillation, heart failure, diabetes mellitus, chronic kidney disease. They also presented with more severe respiratory failure upon admission and showed a more pronounced abnormality in inflammation and kidney function tests. Furthermore, the in-hospital mortality rate was significantly higher in the group with myocardial injury (49.7% vs 14.3%, p < 0.001). After adjusting for age, gender, comorbidities, renal function, and disease severity at admission, myocardial injury emerged as an independent risk factor for in-hospital mortality (OR = 3.758, 95% CI 1.854-7.678, p < 0.001). Among successfully discharged COVID-19 patients, the all-cause mortality rate after a median follow-up of 18.4 months was 7.9%. Patients with myocardial injury had a significantly higher long-term mortality rate compared to those without myocardial injury (14.0% vs. 3.2%, p < 0.001). However, multivariable Cox regression analysis did not find myocardial injury to be a significant predictor of long-term mortality (HR = 2.128, 95% CI 0.792-5.712, p = 0.134). Conclusions: Myocardial injury is a common and serious complication in hospitalized COVID-19 patients, associated with increased in-hospital mortality. However, it does not significantly impact long-term mortality in successfully discharged COVID-19 patients.

Detection and Analysis of Microtubule Nucleator γ-Tubulin Ring Complex.

Golgi-derived microtubules constitute an asymmetrical microtubule network that drives polarized transport of vesicles to support cell polarization and directional migration. Golgi-based microtubule nucleation requires the γ-tubulin ring complex (γTuRC), the principal microtubule nucleator in animal cells. In this chapter, we present methods for detecting γTuRC components and associated proteins on the Golgi, examining Golgi-based microtubule nucleation, and measuring the microtubule-nucleating activity of isolated γTuRCs. These approaches have been demonstrated to be effective for assessing the microtubule-organizing function of the Golgi complex.

The Mutation Spectrum and Two Novel Point Mutations in the APC Gene in Vietnamese Patients with Familial Adenomatous Polyposis.

BACKGROUND: Familial adenomatous polyposis (FAP) is a hereditary disorder primarily caused by germline mutations in the APC gene. The most common type of mutation in the APC gene is point mutation, while deletion mutation is much less frequent. The current study was conducted to investigate the mutation spectrum of the APC gene in Vietnamese FAP patients. METHODS: Patients with the clinical diagnosis of FAP on colorectal endoscopy were screened for mutations in the APC gene using Sanger sequencing. Those who exhibited no point mutation subsequently underwent MLPA assay to detect deletion and duplication mutations. Besides, the relatives of patients with mutated APC genes were recruited for detecting carrier status. RESULTS: Sixty-three patients with clinical colorectal polyposis were recruited. Mutations in the APC gene were detected in 26/63 patients (41.3%). Genetic analysis of 105 asymptomatic relatives of these 26 patients found mutations in the APC gene in 55 individuals (52.4%). CONCLUSION: We successfully established the APC gene mutation spectrum in Vietnamese FAP patients for the first time. Of importance, we discovered two novel point mutations in the APC gene. The high prevalence of carrier status in asymptomatic family members of patients with mutation emphasizes the crucial role of appropriate genetic screening for early diagnosis, surveillance, and preventive measurements.

Preparation of Nanosensors for Detecting the Activity of Glycosaminoglycan Cleaving Enzymes.

Glycosaminoglycans (GAGs) play crucial roles in several biological processes including cell division, angiogenesis, anticoagulation, neurogenesis, axon guidance and growth, and viral and bacterial infections among others. The GAG cleaving hydrolases/lyases play a major role in the control of GAG structures, functions, and turn over. Dysregulation of GAG cleaving enzymes in vivo are linked to a number of human diseases including cancer, diabetes, atherosclerosis, arthritis, inflammation, and cardiovascular diseases. Several GAG cleaving enzymes are widely used for studying GAG glycobiology: heparitinases, chondroitinases, heparanases, hyaluronidases, and keratanases. Herein, we describe a method to synthesize four distinct nanometal surface energy transfer (NSET)-based gold-GAG-dye conjugates (nanosensors). Heparin, chondroitin sulfate, heparan sulfate, and hyaluronic acid are covalently linked with distinct fluorescent dyes and then immobilized on gold nanoparticles (AuNPs) to build nanosensors that serve as excellent substrates for GAG cleaving enzymes. Upon treatment of nanosensors with their respective GAG cleaving enzymes, dye-labeled oligosaccharides/disaccharides are released from AuNPs resulting in enhanced fluorescence recovery. These nanosensors have a great promise as diagnostic tools in various human pathophysiological conditions for detecting dysregulated expression of GAG cleaving enzymes and also as a sensitive analytical tool for assessing the quality control of pharmaceutical grade heparin polysaccharides that are produced in millions of small- and medium-sized animal slaughter houses worldwide.

Anomalous left coronary artery from the pulmonary artery (ALCAPA) as a concealed cause of severe mitral regurgitation in children and adults: Case reports.

INTRODUCTION: Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital coronary artery anomaly and is a concealed cause of mitral regurgitation. PRESENTATION OF CASE: We reported two cases of severe mitral regurgitation in whom the presence of ALCAPA was overlooked in the first cardiac surgery. In the first case, ALCAPA was diagnosed one year after the mitral annuloplasty and the surgical reimplantation was successfully performed. In the second case, ALCAPA was incidentally detected on multislice computerized tomography during preoperative workup for the second surgery to replace the dehiscent mitral prosthesis. DISCUSSION: The clinical presentation of ALCAPA varies highly. It is not difficult to diagnose an ALCAPA in newborns and infants. Contrarily, ALCAPA in children and adults can be overlooked. CONCLUSION: Physicians should always look for the presence of ALCAPA in patients who present with unexplained mitral regurgitation. The surgical strategy in patients with ALCAPA should be carefully individualised to achieve an optimal outcome and alleviate complications.