3,290 research outputs found
The psychosocial burden of psoriasis and barriers to biologic therapy in Hong Kong: patients’ perspectives
This journal suppl. is proceedings of the 18th MRC 2013INTRODUCTION: Psoriatic skin lesions are often visible and have negative impact on patients’ quality of life (QoL). The introduction of biologic therapies has revolutionised the treatment of psoriasis. They are highly efficacious in clearing skin lesions and relieving joint symptoms. The use of biologics in psoriasis patients is associated with improved QoL and patient satisfaction. In Hong Kong, the psychosocial impacts of psoriasis on patients and their satisfaction towards various treatment modalities have not been well studied. Moreover, the ways local patients come to access the information on biologics and their concerns are unclear. METHODS: We conducted a survey of 85 psoriasis …published_or_final_versio
Coastal urbanization leads to remarkable seaweed species loss and community shifts along the SW Atlantic.
Coastal urbanization is rapidly expanding worldwide while its impacts on seaweed communities remain poorly understood. We assessed the impact of urbanization along an extensive latitudinal gradient encompassing three phycogeographical regions in the SW Atlantic. Human population density, number of dwellings, and terrestrial vegetation cover were determined for each survey area and correlated with diversity indices calculated from seaweed percent cover data. Urban areas had significantly lower calcareous algal cover (-38%), and there was significantly less carbonate in the sediment off urban areas than off reference areas. Seaweed richness averaged 26% less in urban areas than in areas with higher vegetation cover. We observed a remarkable decline in Phaeophyceae and a substantial increase of Chlorophyta in urban areas across a wide latitudinal gradient. Our data show that coastal urbanization is causing substantial loss of seaweed biodiversity in the SW Atlantic, and is considerably changing seaweed assemblages
Mitochondrial disease and endocrine dysfunction
Mitochondria are critical organelles for endocrine health; steroid hormone biosynthesis occurs in these organelles and they provide energy in the form of ATP for hormone production and trafficking. Mitochondrial diseases are multisystem disorders that feature defective oxidative phosphorylation, and are characterized by enormous clinical, biochemical and genetic heterogeneity. To date, mitochondrial diseases have been found to result from >250 monogenic defects encoded across two genomes: the nuclear genome and the ancient circular mitochondrial genome located within mitochondria themselves. Endocrine dysfunction is often observed in genetic mitochondrial diseases and reflects decreased intracellular production or extracellular secretion of hormones. Diabetes mellitus is the most frequently described endocrine disturbance in patients with inherited mitochondrial diseases, but other endocrine manifestations in these patients can include growth hormone deficiency, hypogonadism, adrenal dysfunction, hypoparathyroidism and thyroid disease. Although mitochondrial endocrine dysfunction frequently occurs in the context of multisystem disease, some mitochondrial disorders are characterized by isolated endocrine involvement. Furthermore, additional monogenic mitochondrial endocrine diseases are anticipated to be revealed by the application of genome-wide next-generation sequencing approaches in the future. Understanding the mitochondrial basis of endocrine disturbance is key to developing innovative therapies for patients with mitochondrial diseases
Epigenetic regulation of the electrophysiological phenotype of human embryonic stem cell-derived ventricular cardiomyocytes: Insights for driven maturation and hypertrophic growth
Epigenetic regulation is implicated in embryonic development and the control of gene expression in a cell-specific manner. However, little is known about the role of histone methylation changes on human cardiac differentiation and maturation. Using human embryonic stem cells (hESCs) and their derived ventricular (V) cardiomyocytes (CMs) as a model, we examined trimethylation of histone H3 lysine 4 (H3K4me3) and lysine 27 (H3K27me3) on promoters of genes associated with cardiac electrophysiology, contraction, and Ca2+ handling. To avoid ambiguities due to heterogeneous chamber-specific types, hESC-derived ventricular cardiomyocytes (VCMs) were selected by dual zeocin-GFP expression under the transcriptional control of the MLC2v promoter and confirmed electrophysiologically by its signature action potential phenotype. High levels of H3K4me3 are present on pluripotency genes in hESCs with an absence of H3K27me3. Human ESC-VCMS, relative to hESCs, were characterized by a profound loss of H3K27me3 and an enrichment of H3K4me3 marks on cardiac-specific genes, including MYH6, MYH7, MYL2, cTNT, and ANF. Gene transcripts encoding key voltage-gated ion channels and Ca2+-handling proteins in hESC-VCMs were significantly increased, which could be attributed to a distinct pattern of differential H3K4me3 and H3K27me3 profiles. Treatment of hESC-VCMs with the histone deacetylase inhibitor valproic acid increased H3K4me3 on gene promoters, induced hypertrophic growth (as gauged by cell volume and capacitance), and augmented cardiac gene expression, but it did not affect electrophysiological properties of these cells. Hence, cardiac differentiation of hESCs involves a dynamic shift in histone methylation, which differentially affects VCM gene expression and function. We conclude that the epigenetic state of hESC-VCMs is dynamic and primed to promote growth and developmental maturation, but that proper environmental stimuli with chromatin remodeling will be required to synergistically trigger global CM maturation to a more adult-like phenotype. © Mary Ann Liebert, Inc.published_or_final_versio
The Clinical Utility of SUDOSCAN in Chronic Kidney Disease in Chinese Patients with Type 2 Diabetes
published_or_final_versio
A community study on burden and depressive symptoms among carers of demented relatives
Background: Most mild to moderate demented patients
are cared at home. Studies have shown that carers face
increased stress and are prone to depression. In order to
understand their needs, a collaboration study between
District Board, Community Rehabilitation Network and
local hospitals was done. Objective: (1) To understand
care needs of demented patients and their carers in the
family. (2) To assess difficulties faced by carers and evaluate
their stress. (3) To find out which factors may aggravate
or relieve carer stress. Method: The study was performed
by interviewing 100 carers by questionnaire. Three main
themes were studied: (1) presence of depression by Center
for Epidemiological Studies Depression Scale (CES-D), (2)
caregiver burden by Zarit Burden Interview (ZBI), patients’
memory and behavioural problems by Revised Memory
and Behaviour Problems Checklist (RMBPC), patient ADL
performance, and (3) carer coping abilities by Brief COPE
and perceived social support by Multidimensional Scale
of Perceived Social Support (MSPSS). Results: 49% of
patients are in moderate to severe stage, with moderate to
high ADL dependency level (mean ADL score: 62.4, with
40% of patients scoring 60 or below). On average carers
spent 13.8 hours per day on their relative. 24% of carers
have rated self-perceived health status as poor or very
poor. 36% have little or no knowledge about the dementia
illness. Regarding carer depression, 49% had CES-D score
in the moderately and severely depressed range. Caregiver burden was high with ZBI score of 38.2 (>24 being highly
associated with depression). Memory and behavioural
symptoms were common with mean RMBPC 38.2. Carer
coping abilities as measured by Brief COPE was 24.6.
Perceived social support as measured by MSPSS was
56.2. Carer depression was found to be correlated with
cognitive and behaviour problems as well as carer burden;
whereas it was negatively correlated with social support.
After multiple linear regression analysis, caregiver burden
was the most significant factor contributing to caregiver
depression (β=0.55, T=5.43, p<0.001). Conclusions: This
cohort of carers, having spent long hours caring for their
demented relatives had limited knowledge, poor perceived
health and emotional problems. They had high burden
and showed signs of depression. Caregiver depression
was found to be associated with a higher level of burden.published_or_final_versio
Relation of substance use disorders to mortality, accident and emergency department attendances, and hospital admissions: A 13-year population-based cohort study in Hong Kong
BACKGROUND: The impact of substance use disorders (SUD) in an Asian population has not been fully explored. We aimed to assess the risk of mortality, accident and emergency (A&E) department attendances, and hospital admissions associated with SUD in a population-based cohort study. METHOD: Patients diagnosed with SUD in public A&E departments from 2004 to 2016 (N = 8,423) were identified in the Clinical Database Analysis and Reporting System of the Hong Kong Hospital Authority and 1:1 matched to patients without SUD by propensity score (N = 6,074 in each group). Relative risks of mortality, A&E attendances and hospital admissions were assessed using Cox regression and Hurdle negative binomial regression. RESULTS: Patients with SUD had higher mortality (hazard ratio=1.43; 95% confidence interval [CI]=1.26-1.62) and more often died from poisoning or toxicity and injuries. The odds ratio (OR) for A&E attendances and all-cause hospital admissions associated with SUD were 2.80 (95% CI=2.58-3.04) and 3.54 (95% CI=3.26-3.83), respectively. The impact of SUD on the above outcomes was greatest among school-aged individuals (≤ 21 years) and decreased with age. The relative risk of mental disorder-related hospital admissions was much higher than that for infections, respiratory diseases, and cardiovascular diseases. In patients with SUD, ketamine and amphetamine use were associated with increased A&E attendances than opioid use. CONCLUSIONS: SUD was associated with increased mortality, A&E attendances and hospital admissions, especially in school-aged individuals. Our findings suggest prioritising early treatment and preventive interventions for school-aged individuals and focusing on the management of comorbid mental disorders and the use of ketamine and amphetamine
Global Hopf bifurcation in the ZIP regulatory system
Regulation of zinc uptake in roots of Arabidopsis thaliana has recently been
modeled by a system of ordinary differential equations based on the uptake of
zinc, expression of a transporter protein and the interaction between an
activator and inhibitor. For certain parameter choices the steady state of this
model becomes unstable upon variation in the external zinc concentration.
Numerical results show periodic orbits emerging between two critical values of
the external zinc concentration. Here we show the existence of a global Hopf
bifurcation with a continuous family of stable periodic orbits between two Hopf
bifurcation points. The stability of the orbits in a neighborhood of the
bifurcation points is analyzed by deriving the normal form, while the stability
of the orbits in the global continuation is shown by calculation of the Floquet
multipliers. From a biological point of view, stable periodic orbits lead to
potentially toxic zinc peaks in plant cells. Buffering is believed to be an
efficient way to deal with strong transient variations in zinc supply. We
extend the model by a buffer reaction and analyze the stability of the steady
state in dependence of the properties of this reaction. We find that a large
enough equilibrium constant of the buffering reaction stabilizes the steady
state and prevents the development of oscillations. Hence, our results suggest
that buffering has a key role in the dynamics of zinc homeostasis in plant
cells.Comment: 22 pages, 5 figures, uses svjour3.cl
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