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2.
Plant Dis ; : PDIS12222922RE, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38243181

ABSTRACT

Watermelon is affected by diseases such as Fusarium wilt, gummy stem blight, and root-knot nematode (RKN). Succinate dehydrogenase inhibitors (SDHIs) with potential fungicide and nematicide activity provide the opportunity to control multiple diseases with one compound. In this study, we aimed to determine the sensitivity of Meloidogyne incognita race 4 (MI4), Fusarium oxysporum f. sp. niveum (FON), and Stagonosporopsis citrulli (SCIT) to existing SDHIs: benzovindiflupyr, fluopyram, cyclobutrifluram, and pydiflumetofen. All SDHIs had fungicidal activity against 19 SCIT isolates in mycelial growth assays, but isolates were most sensitive to pydiflumetofen (median EC50 = 0.41 µg/ml). Most of the 50 FON isolates tested were sensitive to cyclobutrifluram for mycelial growth (median EC50 = 4.04 µg/ml) and conidial germination (median EC50 = 0.2 µg/ml) assays but were not sensitive to fluopyram. MI4 was most sensitive to cyclobutrifluram for egg hatch (mean EC50 = 0.0019 µg/ml) and J2 motility (mean EC50 = 1.16 µg/ml) assays but was not sensitive to pydiflumetofen. Significant positive correlations between the sensitivity of SCIT (mycelial growth) and FON (mycelial growth and conidial germination) for cyclobutrifluram and benzovindiflupyr (SCIT r = 0.88; FON r = 0.7; P < 0.0001) and cyclobutrifluram and pydiflumetofen (SCIT r = 0.83; FON r = 0.67 and 0.77; P < 0.0001) indicate a potential for cross-resistance between these SDHIs for these fungal pathogens. Overall, results suggest that cyclobutrifluram may be used for managing RKN, whereas it should be used judiciously for Fusarium wilt of watermelon and gummy stem blight due to the existence of insensitive isolates to the fungicide.

3.
Hong Kong Med J ; 29(3): 278-280, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37349146
4.
Hong Kong Med J ; 29(1): 88-90, 2023 02.
Article in English | MEDLINE | ID: mdl-36810247
5.
Hong Kong Med J ; 28(4): 338-339, 2022 08.
Article in English | MEDLINE | ID: mdl-35989439
6.
Chemosphere ; 307(Pt 3): 136018, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35973494

ABSTRACT

The noxious side effects of pesticides on human health and environment have prompted the search of effective and reliable treatment techniques for pesticide removal. The removal of pesticides can be accomplished through physical, chemical and biologicals. Physical approaches such as filtration and adsorption are prevailing pesticide removal strategies on account of their effectiveness and ease of operation. Membrane-based filtration technology has been recognized as a promising water and wastewater treatment approach that can be used for a wide range of organic micropollutants including pesticides. Nanofiltration (NF), reverse osmosis (RO) and forward osmosis (FO) have been increasingly explored for pesticide removal from aquatic environment owing to their versatility and high treatment efficiencies. This review looks into the remedial strategies of pesticides from aqueous environment using membrane-based processes. The potentials and applications of three prevailing membrane processes, namely NF, RO and FO for the treatment of pesticide-containing wastewater are discussed in terms of the development of advanced membranes, separation mechanisms and system design. The challenges in regards to the practical implementation of membrane-based processes for pesticide remediation are identified. The corresponding research directions and way forward are highlighted. An in depth understanding of the pesticide nature, water chemistry and the pesticide-membrane interactions is the key to achieving high pesticide removal efficiency. The integration of membrane technology and conventional removal technologies represents a new dimension and the future direction for the treatment of wastewater containing recalcitrant pesticides.


Subject(s)
Pesticides , Water Purification , Filtration/methods , Humans , Membranes, Artificial , Osmosis , Technology , Wastewater , Water , Water Purification/methods
7.
Hong Kong Med J ; 28(1): 93-95, 2022 02.
Article in English | MEDLINE | ID: mdl-35260503
12.
Hong Kong Med J ; 25(5): 392-398, 2019 10.
Article in English | MEDLINE | ID: mdl-31761748

ABSTRACT

We designed a session of high-fidelity simulation training course for final-year medical students in their emergency medicine specialty clerkship. This was a new initiative with clearly defined learning outcomes. We aimed to evaluate the learning outcomes. Students completed an evaluation form at the end of the session focusing on their perceived learning outcomes. Thematic analysis was conducted for data processing. We collected responses from 149 students. In addition to the intended outcomes of the course, students gained unexpected learning outcomes from the training and some of them matched a few identified learning gaps between undergraduate medical education and their subsequent transition to early clinical practice that have been described in the literature. High-fidelity simulation training in medical school could be an effective tool to address some of the identified gaps in the transition between undergraduate medical education and postgraduate practice.


Subject(s)
Clinical Competence , Education, Medical, Undergraduate , Emergency Medicine/education , High Fidelity Simulation Training , Students, Medical , Attitude of Health Personnel , Hong Kong , Humans , Surveys and Questionnaires
14.
Heliyon ; 5(1): e01142, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30723824

ABSTRACT

Ultrafiltration grade polysulfone-based mixed matrix membranes (MMMs) incorporated with two-dimensional boron nitride nanosheet (BNNS) was prepared via phase inversion method. The amount of BN incorporated was varied and the influence on membrane morphology, contact angle, surface charge, as well as water permeability and humic acid rejection were investigated. Results revealed that the addition of BN to the membrane matrix resulted in profound increase in water permeability (almost tripled to that of neat PSf) and humic acid rejection due to the increase in pore size and surface negative charge. Beyond the morphological changes imparted by the inclusion of BNNS, we postulated that the presence of BNNS within the membrane matrix also contribute to the enhancement in flux and rejection based on surface-slip and selective interlayer transport. Despite the favourable augmentation of water transport and filtration performance, the MMMs suffered with fouling problem due to the entrapment of foulant within the enlarged pores and the membrane valleys. Its inherent adsorptive character could be a disadvantage when utilized as membrane filler.

15.
Hong Kong Med J ; 24(5): 466-472, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30245480

ABSTRACT

INTRODUCTION: Entry into tertiary education is a critical juncture where adolescents proceed to adulthood. This study aimed to determine the prevalence of depression and anxiety, and factors associated with such symptoms, among university undergraduate students in Hong Kong. METHODS: A cross-sectional questionnaire study was employed. A total of 1200 undergraduate students from eight University Grants Committee-funded universities were invited to complete three sets of questionnaires, including the 9-item patient health questionnaire for screening of depressive symptoms, the 7-item generalised anxiety disorder scale for screening of anxiety symptoms, and a socio-demographic questionnaire. RESULTS: Among the valid responses (n=1119) analysed, 767 (68.5%) respondents indicated mild to severe depressive symptoms, which were associated with mild to severe anxiety symptoms. Several lifestyle and psychosocial variables, including regular exercise, self-confidence, satisfaction with academic performance, and optimism towards the future were inversely related with mild to severe depressive symptoms. A total of 599 (54.4%) respondents indicated mild to severe anxiety symptoms, which were associated with level of academic difficulty. Satisfaction with friendship, sleep quality, and self-confidence were inversely associated with mild to severe anxiety symptoms. CONCLUSION: More than 50% of respondents expressed some degree of depressive and anxiety symptoms (68.5% and 54.4%, respectively). Approximately 9% of respondents exhibited moderately severe to severe depressive symptoms; 5.8% exhibited severe anxiety symptoms. Respondents reporting regular exercise, higher self-confidence, and better satisfaction with both friendship and academic performance had fewer depressive and anxiety symptoms.


Subject(s)
Anxiety Disorders/epidemiology , Depressive Disorder/epidemiology , Students/psychology , Adolescent , Adult , Anxiety Disorders/etiology , Anxiety Disorders/psychology , Cross-Sectional Studies , Depressive Disorder/etiology , Depressive Disorder/psychology , Female , Hong Kong/epidemiology , Humans , Male , Prevalence , Psychiatric Status Rating Scales , Surveys and Questionnaires , Universities , Young Adult
16.
Am J Transplant ; 16(12): 3522-3531, 2016 12.
Article in English | MEDLINE | ID: mdl-27184686

ABSTRACT

When transplanted simultaneously, the liver allograft has been thought to have an immunoprotective role on other organs; however, detailed analyses in simultaneous heart-liver transplantation (SHLT) have not been done to date. We analyzed patient outcomes and incidence of immune-mediated injury in 22 consecutive SHLT versus 223 isolated heart transplantation (IHT) recipients between January 2004 and December 2013, by reviewing 3912 protocol- and indication-specific cardiac allograft biopsy specimens. Overall survival was similar (86.4%, 86.4%, and 69.1% for SHLT and 93.3%, 84.7%, and 70.0% for IHT at 1, 5, and 10 years; p = 0.83). Despite similar immunosuppression, the incidence of T cell-mediated rejection (TCMR) was lower in SHLT (31.8%) than in IHT (84.8%) (p < 0.0001). Although more SHLT patients had preexisting donor-specific HLA antibody (22.7% versus 8.1%; p = 0.04), the incidence of antibody-mediated rejection was not different in SHLT compared with IHT (4.5% versus 14.8%, p = 0.33). While the left ventricular ejection fraction was comparable in both groups at 5 years, the incidence and severity of cardiac allograft vasculopathy were reduced in the SHLT recipients (42.9% versus 66.8%, p = 0.03). Simultaneously transplanted liver allograft was associated with reduced risk of TCMR (odds ratio [OR] 0.003, 95% confidence interval [CI] 0-0.02; p < 0.0001), antibody-mediated rejection (OR 0.04, 95% CI 0-0.46; p = 0.004), and cardiac allograft vasculopathy (OR 0.26, 95% CI 0.07-0.84; p = 0.02), after adjusting for other risk factors. These data suggest that the incidence of alloimmune injury in the heart allograft is reduced in SHLT recipients.


Subject(s)
Allografts/immunology , Graft Rejection/prevention & control , Graft Survival/immunology , Heart Transplantation , Liver Transplantation , Postoperative Complications/prevention & control , Female , Follow-Up Studies , Graft Rejection/epidemiology , Graft Rejection/immunology , Heart Diseases/surgery , Humans , Incidence , Liver Diseases/surgery , Male , Middle Aged , Minnesota/epidemiology , Postoperative Complications/epidemiology , Postoperative Complications/immunology , Prognosis , Risk Factors
17.
J Microsc ; 263(1): 34-42, 2016 07.
Article in English | MEDLINE | ID: mdl-26695532

ABSTRACT

The chitosan has been used as the primary excipient in transdermal particulate dosage form design. Its distribution pattern across the epidermis and dermis is not easily accessible through chemical assay and limited to radiolabelled molecules via quantitative autoradiography. This study explored Fourier-transform infrared spectroscopy imaging technique with built-in microscope as the means to examine chitosan molecular distribution over epidermis and dermis with the aid of histology operation. Fourier-transform infrared spectroscopy skin imaging was conducted using chitosan of varying molecular weights, deacetylation degrees, particle sizes and zeta potentials, obtained via microwave ligation of polymer chains at solution state. Both skin permeation and retention characteristics of chitosan increased with the use of smaller chitosan molecules with reduced acetyl content and size, and increased positive charge density. The ratio of epidermal to dermal chitosan content decreased with the use of these chitosan molecules as their accumulation in dermis (3.90% to 18.22%) was raised to a greater extent than epidermis (0.62% to 1.92%). A larger dermal chitosan accumulation nonetheless did not promote the transdermal polymer passage more than the epidermal chitosan. A small increase in epidermal chitosan content apparently could fluidize the stratum corneum and was more essential to dictate molecular permeation into dermis and systemic circulation. The histology technique aided Fourier-transform infrared spectroscopy imaging approach introduces a new dimension to the mechanistic aspect of chitosan in transdermal delivery.


Subject(s)
Chitosan/administration & dosage , Chitosan/analysis , Histological Techniques/methods , Ninhydrin , Skin/chemistry , Spectroscopy, Fourier Transform Infrared/methods , Administration, Cutaneous , Animals , Chitosan/chemistry , Chitosan/pharmacokinetics , Male , Molecular Weight , Ninhydrin/analysis , Rats , Skin/metabolism
18.
Clin Pharmacol Ther ; 99(5): 555-61, 2016 May.
Article in English | MEDLINE | ID: mdl-26599303

ABSTRACT

Thioamides antithyroid-drugs (ATDs) are important in hyperthyroid disease management. Identification of the susceptibility locus of ATD-induced agranulocytosis is important for clinical management. We performed a genome-wide association study (GWAS) involving 20 patients with ATD-induced agranulocytosis and 775 healthy controls. The top finding was further replicated. A single-nucleotide polymorphism (SNP), rs185386680, showed the strongest association with ATD-induced agranulocytosis in GWAS (odds ratio (OR) = 36.4; 95% confidence interval (CI) = 12.8-103.7; P = 1.3 × 10(-24)) and replication (OR = 37; 95% CI = 3.7-367.4; P = 9.6 × 10(-7)). HLA-B*38:02:01 was in complete linkage disequilibrium with rs185386680. High-resolution HLA typing confirmed that HLA-B*38:02:01 was associated with carbimazole (CMZ)/methimazole (MMI)-induced agranulocytosis (OR = 265.5; 95% CI = 27.9-2528.0; P = 2.5 × 10(-14)), but not associated with propylthiouracil (PTU). The positive and negative predictive values of HLA-B*38:02:01 in predicting CMZ/MMI-induced agranulocytosis were 0.07 and 0.999. Approximately 211 cases need to be screened to prevent one case. Screening for the risk allele will be useful in preventing agranulocytosis in populations in which the frequency of the risk allele is high.


Subject(s)
Agranulocytosis/chemically induced , Antithyroid Agents/adverse effects , Carbimazole/adverse effects , HLA-B Antigens/genetics , Methimazole/adverse effects , Agranulocytosis/genetics , Antithyroid Agents/administration & dosage , Carbimazole/administration & dosage , Case-Control Studies , Female , Genome-Wide Association Study , Humans , Linkage Disequilibrium/genetics , Methimazole/administration & dosage , Polymorphism, Single Nucleotide , Predictive Value of Tests , Propylthiouracil/administration & dosage , Propylthiouracil/adverse effects
19.
Cogn Process ; 16 Suppl 1: 421-4, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26233524

ABSTRACT

Older repeat fallers have previously been shown to have a higher propensity to consciously monitor and control their movements (i.e. reinvestment) than non-fallers, yet to direct their attention equally between their limb movements and the external environment during locomotion (Wong et al. in J Am Geriatr Soc 57: 920-922, 2009). Whether increased attention to their movements is a result of falling or originates from a prior inclination to reinvest remains unclear. In order to better understand the interaction between reinvestment and attention during locomotion, this study examined the allocation of attention by older adults who had not fallen but displayed a high or low inclination for reinvestment. Twenty-eight low and twenty-eight high reinvestors were required to perform 30 walking trials. Their allocation of attention during walking was evaluated by asking tone-related attentional focus questions shortly after finishing each walking trial. High reinvestors were found to be more aware of their limb movements and less aware of the external environment. Low reinvestors, on the contrary, were more aware of the surrounding environment and less aware of their movement mechanics. Given that focusing internally to body movements has been proposed to utilise working memory capacity, the ability of high reinvestors to pick up all the environmental information necessary for successful locomotion might be compromised and requires further examination.


Subject(s)
Attention/physiology , Movement/physiology , Personal Space , Walking/physiology , Aged , Awareness , Environment , Female , Humans , Male , Mental Status Schedule , Statistics, Nonparametric
20.
Br J Dermatol ; 172(4): 1111-5, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25234635

ABSTRACT

The physiology of human skin pigmentation is varied and complex, with an extensive melanogenic paracrine network involving mesenchymal and epithelial cells, contributing to the regulation of melanocyte survival and proliferation and melanogenesis. Mutations in several genes, involving predominantly the KIT ligand/c-Kit and Ras/mitogen-activated protein kinase signalling pathways, have been implicated in a spectrum of diseases in which there is hyperpigmentation, hypopigmentation or both. Here, we report on a 12-year-old girl from Taiwan with a 6-year history of diffuse progressive skin hyperpigmentation resulting from a different aetiology: an inborn metabolic disorder of vitamin B12 (cobalamin), designated cblJ. Using whole-exome sequencing we identified a homozygous mutation in ABCD4 (c.423C>G; p.Asn141Lys), which encodes an ATP-binding cassette transporter with a role in the intracellular processing of cobalamin. The patient had biochemical and haematological evidence of cobalamin deficiency but no other clinical abnormalities apart from a slight lightening of her previously black hair. Of note, she had no neurological symptoms or signs. Treatment with oral cobalamin (3 mg daily) led to metabolic correction and some reduction in the skin hyperpigmentation at the 3-month follow-up. This case demonstrates that defects or deficiencies of cobalamin should be remembered in the differential diagnosis of diffuse hyperpigmentary skin disorders.


Subject(s)
ATP-Binding Cassette Transporters/genetics , Hyperpigmentation/genetics , Metabolism, Inborn Errors/genetics , Mutation/genetics , Polymorphism, Single Nucleotide/genetics , Vitamin B 12 Deficiency/genetics , Child , Female , Homozygote , Humans , Hyperpigmentation/drug therapy , Metabolism, Inborn Errors/drug therapy , Vitamin B 12/therapeutic use , Vitamin B 12 Deficiency/drug therapy , Vitamin B Complex/therapeutic use
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