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1.
Plants (Basel) ; 13(2)2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38276778

RESUMO

Phellinus noxius is a highly destructive fungus that causes brown root disease in trees, leading to decay and death. In Taiwan, five prized woods-Taiwania cryptomerioides, Calocedrus macrolepis var. formosana, Cunninghamia lanceolata var. konishii, Chamaecyparis formosensis, and Chamaecyparis obtusa var. formosana-are known for their fragrance and durability. This study aims to explore the anti-brown-root-rot-fungus activity of Cunninghamia lanceolata var. konishii (CL) essential oil (CLOL) and its primary components, while also delving into their mechanisms of action and inhibition pathways. The essential oil (CLOL) from CL wood demonstrated significant efficacy against P. noxius, with an inhibitory concentration (IC50) of 37.5 µg/mL. Cedrol, the major component (78.48%) in CLOL, emerged as a potent antifungal agent, surpassing the reference drug triflumizole. Further assays with cedrol revealed a stronger anti-brown-root-disease activity (IC50 = 15.7 µg/mL) than triflumizole (IC50 = 32.1 µg/mL). Scanning electron microscopy showed deformation and rupture of fungal hyphae treated with CLOL and cedrol, indicating damage to the fungal cell membrane. Cedrol-induced oxidative stress in P. noxius was evidenced by increased reactive oxygen species (ROS) levels, leading to DNA fragmentation, mitochondrial membrane potential reduction, and fungal apoptosis through the mitochondrial pathway. Gel electrophoresis confirmed cedrol-induced DNA fragmentation, whereas TUNEL staining demonstrated increased apoptosis with rising cedrol concentrations. Moreover, protein expression analysis revealed cedrol-triggered release of cytochrome c, activation of caspase-9, and subsequent caspase-3 activation, initiating a caspase cascade reaction. This groundbreaking study establishes cedrol as the first compound to induce apoptosis in P. noxius while inhibiting its growth through oxidative stress, an increase in mitochondrial membrane permeability, and activation of the mitochondrial pathway. The findings offer compelling evidence for cedrol's potential as an effective antifungal agent against the destructive brown root disease caused by P. noxius.

2.
Lancet Microbe ; 4(6): e418-e430, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37086735

RESUMO

BACKGROUND: The primary aim of using vaccines in public health responses to SARS-CoV-2 variants of concern is to reduce incidence of severe disease, for which T-cell responses are essential. There is a paucity of data on vaccine-induced T-cell immunity to omicron (B.1.1.529). We aimed to compare SARS-CoV-2 omicron BA.1-specific T-cell responses in adults vaccinated with CoronaVac or BNT162b2. METHODS: For this observational cohort, we recruited adults (aged ≥18 years) from three vaccination centres in Hong Kong. We included participants from four cohorts (cohort 1: participants who received two doses of either BNT162b2 or CoronaVac, cohort 2: participants who received two doses and a booster, cohort 3: participants who received two doses and a booster and had a breakthrough omicron infection, and cohort 4: participants who had a previous non-omicron infection and subsequently received one dose of vaccine). People with confirmed history of COVID-19 at recruitment were excluded from cohort 1 and cohort 2. We collected blood samples before vaccination (for cohort 1 and 2), 1-month following vaccination (for all cohorts), and during convalescence for cohort 3 and 4) and determined the proportion of IFNγ+CD4+ and IFNγ+CD8+ T cells in peripheral blood against SARS-CoV-2 using flow cytometry with peptide pools of SARS-CoV-2 wild type or omicron BA.1. The primary outcome was proportion of CD4+ and CD8+ T cells against SARS-CoV-2 1 month after exposure (ie, vaccination or breakthrough infection). FINDINGS: Overall, between May 21, 2020, and Aug 31, 2021, we recruited 659 participants (231 [35%] men and 428 [65%] women). Of these participants, 428 were included in cohort 1 (214 [50%] received BNT162b2 and 214 [50%] received CoronaVac); 127 in cohort 2 (48 [38%] received all BNT162b2, 40 [31%] received all CoronaVac, and 39 [31%] received two CoronaVac and a booster with BNT162b2); 58 in cohort 3, and 46 in cohort 4 (16 [35%] received CoronaVac and 30 [65%] received BNT162b2). Vaccine-induced T-cell responses to the wild-type and omicron BA.1 variants were generally similar in adults receiving two doses of either CoronaVac (CD4+ cells p=0·33; CD8+ cells p=0·70) or BNT162b2 (CD4+ cells p=0·28; CD8+ cells p=1·0). Using a peptide pool of all structural proteins for stimulation, BNT162b2 induced a higher median frequency of omicron-specific CD4+ T cells in adults younger than 60 years (CD4+ cells 0·012% vs 0·010%, p=0·031; CD8+ cells 0·003% vs 0·000%, p=0·055) and omicron-specific CD8+ T cells in people aged 60 years or older (CD4+ cells 0·015% vs 0·006%, p=0·0070; CD8+ cells 0·007% vs 0·000%, p=0·035). A booster dose of either BNT162b2 or CoronaVac after two doses of CoronaVac boosted waning T-cell responses, but T-cell responses did not exceed those at 1 month after the second dose (CoronaVac CD4+ p=0·41, CD8+ p=0·79; BNT162b2 CD4+ p=0·70 CD8+ p=0·80). INTERPRETATION: The evidence that mRNA and inactivated vaccines based on the ancestral SARS-CoV-2 virus elicited T-cell responses to SARS-CoV-2 omicron variants might explain the high observed vaccine effectiveness against severe COVID-19 shown by both types of vaccine, despite great differences in neutralising antibody responses. The use of either vaccine can be considered if the primary aim is to reduce severity and death caused by the new omicron subvariants; however, BNT162b2 is preferable for adults older than 60 years. FUNDING: The Health and Medical Research Fund Commissioned Research on the Novel Coronavirus Disease and S H Ho Foundation.


Assuntos
Linfócitos T CD8-Positivos , COVID-19 , Masculino , Humanos , Adulto , Feminino , Adolescente , Vacina BNT162 , Hong Kong/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Infecções Irruptivas , Estudos de Coortes
3.
BMC Prim Care ; 24(1): 48, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36788489

RESUMO

BACKGROUND: Service gaps exist in oral anticoagulant (OAC) use among patients with atrial fibrillation (AF) in primary care. The purpose of this study was to explore the clinical effectiveness of a community dwelling Atrial Fibrillation Special Clinic (AFSC) run by primary care physicians by evaluating its impact on OAC use and the control of modifiable cardiovascular disease (CVD) risk factors in high risk AF patients. METHOD: Quasi-experimental study was conducted in AFSC run by public primary care physicians in Hong Kong. Study subjects were high risk AF patients with CHA2DS2-VASc scores ≥ 2, who had been followed up (FU) at AFSC for at least one year from 01 August, 2019 to 31 October, 2020. OAC usage and modifiable CVD risk factor control were compared before and after one year of FU at AFSC. Drug-related adverse events, emergency attendance or hospitalisation episodes, survival and mortality rates after one year FU at AFSC were also reviewed. RESULTS: Among the 299 high risk AF patients included in the study, significant increase in OAC use was observed from 58.5% at baseline to 82.6% after one year FU in AFSC (P < 0.001). Concerning CVD risk factor control, the average diastolic blood pressure level was significantly reduced (P = 0.009) and the satisfactory blood pressure control rate in non-diabetic patients was markedly improved after one year FU (P = 0.049). However, the average HbA1c and LDL-c levels remained static. The annual incidence rate of ischaemic stroke/systemic embolism was 0.4%, intra-cranial haemorrhage was 0.4%, major bleeding episode was 3.2% and all-cause mortality was 4.3%, all of which were comparable to reports in the literature. CONCLUSION: AFSC is effective in enhancing OAC use and maintaining optimal modifiable CVD risk factor control among high risk AF patients managed in primary care setting, and therefore may reduce AF-associated morbidity and mortality in the long run.


Assuntos
Fibrilação Atrial , Isquemia Encefálica , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/induzido quimicamente , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Isquemia Encefálica/induzido quimicamente , Isquemia Encefálica/complicações , Anticoagulantes/efeitos adversos , Fatores de Risco
4.
Nutr Diet ; 78(3): 296-304, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34159690

RESUMO

BACKGROUND: There is a need for quick and easy methods to monitor nutritional intake in hospital and identify patients with poor intake. Food record charts are often used in clinical practice, with low levels of accuracy and completion. This study aims to describe the development and evaluate the performance of a new tool to estimate energy and protein intake and identify poor nutritional intake amongst adult hospital patients. METHODS: Ninety trays were sampled and assessed independently using the new tool 'Meal Intake Points' and a weighed (reference) method. The performance was tested by measuring association (Spearman's correlation), agreement (proportion of meals within specified limits of reference method), and sensitivity and specificity to identify poor energy and protein intake. RESULTS: This new tool achieved very strong association for energy estimates (r = .91) and strong association for protein estimates (r = .86). Estimates for energy and protein were within 450 kJ and 4.5 g of the reference method in 77.8% and 62.2% of meals, respectively. It also displayed excellent performance as a screening tool (sensitivity 100%; specificity 76%-80%). Minor revision of the original tool was needed to optimise performance. CONCLUSIONS: Meal Intake Points accurately estimates energy and protein intake and identifies patients with poor nutritional intake, providing a clinically relevant tool for use in hospitals to monitor intake and identify patients for proactive nutrition support. Further validation studies are needed to determine its performance in clinical practice and whether it is useful in predicting hospital-acquired malnutrition.


Assuntos
Ingestão de Energia , Desnutrição , Ingestão de Alimentos , Hospitais , Humanos , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Refeições
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