61 research outputs found
Ontogenetic Changes in Feeding Ecology and Habitat of the Damselfish Neoglyphidodon melas at Lizard Island, Great Barrier Reef
This study examines ontogenetic shift in habitat and feeding ecology of the black damselfish, Neoglyphidodon melas in three patch reef sites at Lizard Island, Great Barrier Reef. This rarely studied species is unique in its coprophagous relationship with the faeces of the giant clam Tridacna gigas. Distribution and habitat composition between three sites and two reef zones was estimated with 48 Visual Belt and Point Intercept Transects. 80 Focal Animal Studies revealed specific foraging strategies and aggressive behaviours. The timing of this study permitted the inclusion of juvenile recruits resulting in a more complete and comprehensive study across developmental stages. Major results showed marked ontogenetic shifts in both habitat usage and feeding strategies. Recruits fed solely on plankton and were generally found over heads of digitate Acropora. Older juveniles added soft coral to their diet, which was also a major benthic component in high density areas. Only adults consumed clam faeces in addition to soft coral, and larger adults consumed more faeces than smaller adults. Adult distribution was affected by soft coral and rubble, which positively affected clam occupation. Larger fish exhibited greater aggression towards conspecifics and non-conspecifics, but adult fish occupying clams had a lower rate of chasing compared with adults without clams. Protein-rich clam faeces is an important dietary component for large adult fish
Prevalence and correlates of subjective cognitive impairment in Chinese psychiatric patients during the fifth wave of COVID-19 in Hong Kong
IntroductionThe extent of cognitive impairment and its association with psychological distress among people with pre-existing mental illness during COVID-19 is understudied. This study aimed to investigate prevalence and correlates of subjective cognitive impairment (SCI) in Chinese psychiatric patients during fifth-wave of COVID-19 in Hong Kong (HK).MethodsFour-hundred-eight psychiatric outpatients aged 18–64 years were assessed with questionnaires between 28 March and 8 April 2022, encompassing illness profile, psychopathological symptoms, coping-styles, resilience, and COVID-19 related factors. Participants were categorized into moderate-to-severe and intact/mild cognitive impairment (CI+ vs. CI-) groups based on severity of self-reported cognitive complaints. Univariate and multivariate regression analyses were conducted to determine variables associated with CI+ status.ResultsOne-hundred-ninety-nine participants (48.8%) experienced CI+. A multivariate model on psychopathological symptoms found that depressive and post-traumatic-stress-disorder (PTSD)-like symptoms were related to CI+, while a multivariate model on coping, resilience and COVID-19 related factors revealed that avoidant coping, low resilience and more stressors were associated with CI+. Final combined model demonstrated the best model performance and showed that more severe depressive and PTSD-like symptoms, and adoption of avoidant coping were significantly associated with CI+.ConclusionAlmost half of the sample of psychiatric patients reported cognitive complaints during fifth-wave of COVID-19 in HK. Greater depressive and PTSD-like symptom severity, and maladaptive (avoidant) coping were found as correlates of SCI. COVID-19 related factors were not independently associated with SCI in psychiatric patients. Early detection with targeted psychological interventions may therefore reduce psychological distress, and hence self-perceived cognitive difficulties in this vulnerable population
Evaluation of hazardous airborne carbonyls in five urban roadside dwellings: A comprehensive indoor air assessment in Sri Lanka
Indoor hazardous airborne carbonyls were quantified in five natural-ventilated roadside dwellings in Colombo, Sri Lanka. The total concentrations of all targeted carbonyls ranged from 13.6 to 18.6 mu g/m(3). Formaldehyde (C1) was the most abundant carbonyl, followed by acetaldehyde (C2) and acetone (C3K). The concentrations of C1 and C2 ranged from 3.3 to 8.5 mu g/m(3) and 2.3 to 4.4 mu g/m(3), respectively, which accounted for 23 to 42% and 18 to 26% respectively, to the total quantified carbonyls. The highest carbonyls levels were obtained in the dwelling located in an urban district with a mixture of industrial, commercial and residential areas. Much lower concentrations of carbonyls were measured in a light local traffic value was counted. Moderate correlations between individual combustion markers from vehicular emissions suggest the strong impacts from traffics to the indoor airs. The concentrations of C1 and C2 were compared with international indoor guidelines established by different authorities. A health assessment was conducted by estimation of inhalation cancer risk, implementing the inhalation unit risk values provided by Integrated Risk Information System (IRIS), associated with C1 and C2, which were 6.2 x 10(-5) and 7.7 x 10(-6), respectively. Even though the risks did not reach the action level (1 x 10(-4)), their health impact should not be overlooked. This kick-off indoor monitoring study provides valuable scientific data to the environmental science community since only limit data is available in Sri Lanka
A novel Hsp90 inhibitor AT13387 induces senescence in EBV-positive nasopharyngeal carcinoma cells and suppresses tumor formation
Background: Nasopharyngeal carcinoma (NPC) is an epithelial malignancy strongly associated with Epstein-Barr virus (EBV). AT13387 is a novel heat shock protein 90 (Hsp90) inhibitor, which inhibits the chaperone function of Hsp90 and reduces expression of Hsp90-dependent client oncoproteins. This study aimed to evaluate both the in vitro and in vivo antitumor effects of AT13387 in the EBV-positive NPC cell line C666-1.Results: Our results showed that AT13387 inhibited C666-1 cell growth and induced cellular senescence with the downregulation of multiple Hsp90 client oncoproteins EGFR, AKT, CDK4, and restored the protein expression of negative cell cycle regulator p27. We also studied the ability of AT13387 to restore p27 expression by downregulation of AKT and the p27 ubiquitin mediator, Skp2, using AKT inhibitor and Skp2 siRNA. In the functional study, AT13387 inhibited cell migration with downregulation of a cell migration regulator, HDAC6, and increased the acetylation and stabilization of α-tubulin. We also examined the effect of AT13387 on putative cancer stem cells (CSC) by 3-D tumor sphere formation assay. AT13387 effectively reduced both the number and size of C666-1 tumor spheres with decreased expression of NPC CSC-like markers CD44 and SOX2. In the in vivo study, AT13387 significantly suppressed tumor formation in C666-1 NPC xenografts.Conclusion: AT13387 suppressed cell growth, cell migration, tumor sphere formation and induced cellular senescence on EBV-positive NPC cell line C666-1. Also, the antitumor effect of AT13387 was demonstrated in an in vivo model. This study provided experimental evidence for the preclinical value of using AT13387 as an effective antitumor agent in treatment of NPC. © 2013 Chan et al.; licensee BioMed Central Ltd.published_or_final_versio
Intermolecular CT excitons enable nanosecond excited-state lifetimes in NIR-absorbing non-fullerene acceptors for efficient organic solar cells
State-of-the-art Y6-type molecular acceptors exhibit nanosecond excited-state
lifetimes despite their low optical gaps (~1.4 eV), thus allowing organic solar
cells (OSCs) to achieve highly efficient charge generation with extended
near-infrared (NIR) absorption range (up to ~1000 nm). However, the precise
molecular-level mechanism that enables low-energy excited states in Y6-type
acceptors to achieve nanosecond lifetimes has remained elusive. Here, we
demonstrate that the distinct packing of Y6 molecules in film leads to a strong
intermolecular charge-transfer (iCT) character of the lowest excited state in
Y6 aggregates, which is absent in other low-gap acceptors such as ITIC. Due to
strong electronic couplings between the adjacent Y6 molecules, the iCT-exciton
energies are greatly reduced by up to ~0.25 eV with respect to excitons formed
in separated molecules. Importantly, despite their low energies, the iCT
excitons have reduced non-adiabatic electron-vibration couplings with the
electronic ground state, thus suppressing non-radiative recombination and
allowing Y6 to overcome the well-known energy gap law. Our results reveal the
fundamental relationship between molecular packing and nanosecond excited-state
lifetimes in NIR-absorbing Y6-type acceptors underlying the outstanding
performance of Y6-based OSCs
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Early intervention for incipient insanity: early notions from the 19th century English literature.
AIM: Early intervention programmes in mental illnesses started to bloom in the 1990s, and many programmes have been established worldwide during the past twenty years. However, the concept of early intervention has emerged during the 19th century but it did not make much impact on practice. The aim of this review is to identify the difficulties appeared during that period of time which could provide insight into the modern development of early intervention initiatives. METHODS: A narrative review which focused on English literature about early intervention for insanity during the 19th century was undertaken. RESULTS: Clinicians during the 19th century recognized that treatment would be the most effective at the early stage of the mental illness and they had emphasized the importance of early intervention. However, because of a number of factors, such as the limited roles of asylums, lack of knowledge about mental disorder and the lack of effective treatment, the idea of early intervention did not make impact in clinical service during that period of time. CONCLUSION: During the past two hundred years, understanding towards mental illness has advanced and more effective treatments, such as the use of anti-psychotic medications, have been developed. Reflecting on the past experience and difficulties might shed light on the development of today early intervention in mental disorder.This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by Wiley
Predictive value of neutrophil-to-lymphocyte ratio for atrial fibrillation and stroke in type 2 diabetes mellitus: The Hong Kong Diabetes Study
Neutrophil-to-lymphocyte ratio (NLR) is a routinely available biomarker that reflects systemic inflammation. The study evaluated the predictive value of NLR for ischemic stroke and atrial fibrillation (AF) in patients with type 2 diabetes mellitus. This was a population-based cohort study of patients with type 2 diabetes mellitus and complete blood count tests at baseline between 1 January 1st, 2009, and 31 December, 2009, at government-funded hospitals/clinics in Hong Kong. Follow-up was until 31 December, 2019, or death. A total of 85,351 patients (age = 67.6 ± 13.2 years old, male = 48.8%, follow-up = 3101 ± 1441 days) were included. Univariable Cox regression found that increased NLR at quartiles 2, 3 and 4 was significantly associated with higher risks of new-onset ischemic stroke (hazard ratio [HR]: 1.28 [1.20-1.37], p < .001, HR: 1.41 [1.32-1.51], p < .001 and HR: 1.38 [1.29-1.47], p < .001) and AF (HR: 1.09 [1.02-1.17], p < .015; HR: 1.28 [1.20-1.37], p < .001; HR: 1.39 [1.31-1.49], p < .001) compared to quartile 1. On multivariable analysis, NLR remained a significant predictor of ischemic stroke risk for quartiles 2 and 3 (quartile 2: HR: 1.14 [1.05, 1.22], p = .001; quartile 3: HR: 1.14 [1.06, 1.23], p < .001) but not quartile 4 (HR: 1.08 [0.994, 1.17], p = .070). NLR was not predictive of AF after adjusting for confounders (quartile 2: HR: 0.966 [0.874, 1.07], p = .499; quartile 3: HR: 0.978 [0.884, 1.08], p = .661; quartile 4: HR: 1.05 [0.935, 1.16], p = .462). NLR is a significant predictor of new-onset ischaemic stroke after adjusting for significant confounders in Chinese type 2 diabetes patients
Reactivation of Epstein–Barr virus by a dual-responsive fluorescent EBNA1-targeting agent with Zn2+-chelating function
EBNA1 is the only Epstein–Barr virus (EBV) latent protein responsible for viral genome maintenance and is expressed in all EBV-infected cells. Zn2+ is essential for oligomerization of the functional EBNA1. We constructed an EBNA1 binding peptide with a Zn2+ chelator to create an EBNA1-specific inhibitor (ZRL5P4). ZRL5P4 by itself is sufficient to reactivate EBV from its latent infection. ZRL5P4 is able to emit unique responsive fluorescent signals once it binds with EBNA1 and a Zn2+ ion. ZRL5P4 can selectively disrupt the EBNA1 oligomerization and cause nasopharyngeal carcinoma (NPC) tumor shrinkage, possibly due to EBV lytic induction. Dicer1 seems essential for this lytic reactivation. As can been seen, EBNA1 is likely to maintain NPC cell survival by suppressing viral reactivation
Milk Consumption Across Life Periods in Relation to Lower Risk of Nasopharyngeal Carcinoma: A Multicentre Case-Control Study
Background: The much higher incidence of nasopharyngeal carcinoma (NPC) in men suggests sex hormones as a risk factor, and dairy products contain measurable amounts of steroid hormones. Milk consumption has greatly increased in endemic regions of NPC. We investigated the association between NPC and milk consumption across life periods in Hong Kong.Methods: A multicentre case-control study included 815 histologically confirmed NPC incident cases and 1,502 controls who were frequency-matched on age and sex at five major hospitals in Hong Kong in 2014–2017. Odds ratios (ORs) of NPC (cases vs. controls) for milk consumption at different life periods were estimated by unconditional logistic regression, adjusting for sex, age, socioeconomic status score, smoking and alcohol drinking status, exposure to occupational hazards, family history of cancer, IgA against Epstein-Barr virus viral capsid antigen, and total energy intake.Results: Compared with abstainers, lower risks of NPC were consistently observed in regular users (consuming ≥5 glasses of milk [fresh and powdered combined] per month) across four life periods of age 6–12 (adjusted OR 0.74, 95% CI 0.54–0.86), 13–18 (0.68, 0.55–0.84), 19–30 (0.68, 0.55–0.84), and 10 years before recruitment (0.72, 0.59–0.87). Long-term average milk consumption of ≤2.5, >2.5, and ≤12.5, >12.5 glasses per month yielded adjusted OR (95% CI) of 1.00 (0.80–1.26), 0.98 (0.81–1.18), 0.95 (0.76–1.18), and 0.55 (0.43–0.70), respectively (all P-values for trend < 0.05).Conclusion: Consumption of milk across life periods was associated with lower risks of NPC. If confirmed to be causal, this has important implications for dairy product consumption and prevention of NPC
Apolipoprotein M Gene (APOM) Polymorphism Modifies Metabolic and Disease Traits in Type 2 Diabetes
This study aimed at substantiating the associations of the apolipoproein M gene (APOM) with type 2 diabetes (T2D) as well as with metabolic traits in Hong Kong Chinese. In addition, APOM gene function was further characterized to elucidate its activity in cholesterol metabolism. Seventeen APOM SNPs documented in the NCBI database were genotyped. Five SNPs were confirmed in our study cohort of 1234 T2D and 606 control participants. Three of the five SNPs rs707921(C+1871A), rs707922(G+1837T) and rs805264(G+203A) were in linkage disequilibrium (LD). We chose rs707922 to tag this LD region for down stream association analyses and characterized the function of this SNP at molecular level. No association between APOM and T2D susceptibility was detected in our Hong Kong Chinese cohort. Interestingly, the C allele of rs805297 was significantly associated with T2D duration of longer than 10 years (OR = 1.245, p = 0.015). The rs707922 TT genotype was significantly associated with elevated plasma total- and LDL- cholesterol levels (p = 0.006 and p = 0.009, respectively) in T2D patients. Molecular analyses of rs707922 lead to the discoveries of a novel transcript APOM5 as well as the cryptic nature of exon 5 of the gene. Ectopic expression of APOM5 transcript confirmed rs707922 allele-dependent activity of the transcript in modifying cholesterol homeostasis in vitro. In conclusion, the results here did not support APOM as a T2D susceptibility gene in Hong Kong Chinese. However, in T2D patients, a subset of APOM SNPs was associated with disease duration and metabolic traits. Further molecular analysis proved the functional activity of rs707922 in APOM expression and in regulation of cellular cholesterol content
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