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1.
Food Chem ; 418: 135807, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36989643

RESUMO

While fruit biowastes pose an environmental hazard, they can be utilized as a source of beneficial biopolymers such as pectin. However, conventional extraction techniques require long processing time with low, impure yields, and microwave assisted extraction (MAE) can suffer from these drawbacks. Here, MAE was applied to extract pectin from jackfruit rags and compared with conventional heating reflux extraction (HRE). Response surface methodology was adopted to optimize pectin yield, based on pH (1.0-2.0), solid-liquid ratio (1:20-1:30), time (5-90 min), and temperature (60-95 °C). Pectin extraction by MAE required lower temperatures (65.99 °C) and shorter reaction times (10.56 min). Pectin HRE resulted in a product with amorphous structures and rough surfaces, while pectin-MAE was high crystalline with smooth surfaces. Although both pectin samples showed shear-thinning behavior, pectin-MAE exhibited higher antioxidant and antibacterial activities. Therefore, microwave assisted extraction was an efficient method to extract pectin from jackfruit rags.


Assuntos
Artocarpus , Pectinas , Artocarpus/química , Frutas/química , Micro-Ondas , Pectinas/química , Temperatura , Antibacterianos/química , Antibacterianos/farmacologia , Fenômenos Químicos
2.
Drugs Context ; 112022.
Artigo em Inglês | MEDLINE | ID: mdl-36544626

RESUMO

Background: Hyperfunctional platelets play important roles in thromboembolism in patients with ß-thalassaemia/ haemoglobin E (ß-thal/HbE). Our previous study revealed ex vivo inhibitory effects of deferiprone on normal platelets. Herein, we aimed to investigate the in vivo effects on platelets in patients with ß-thal/HbE. Methods: A prospective, self-controlled clinical study on 30 patients with ß-thal/HbE who had received therapeutic deferiprone (20.8-94.5 mg/kg/day) was conducted. The study included a 4-week washout period followed by 4 and 12 weeks of deferiprone treatment. Platelet aggregation was performed by a turbidimetric method. Levels of deferiprone and soluble platelet (sP)-selectin in serum were measured by high-performance liquid chromatography (HPLC) and enzyme-linked immunosorbent assay (ELISA) kit, respectively. Results: The washout period significantly enhanced platelet hyperactivity both in patients who had undergone splenectomy and in those who had not. At 2 hours following the administration of a single dose of deferiprone, platelet sensitivity to ADP and arachidonic acid was significantly reduced. The inhibitory effects of deferiprone were gradually increased over the period of 4 and 12 weeks. Deferiprone also depressed sP-selectin levels, but the effect was stable over longer follow-up periods. Correlation analysis demonstrated the relationship between serum levels of deferiprone, sP-selectin, and platelet activities induced by ADP and arachidonic acid. Conclusion: We first demonstrated the in vivo antiplatelet effect and benefit of short-term treatment of deferiprone in patients with ß-thal/HbE. The impact on thrombotic outcomes deserves further study.

3.
Trop Med Infect Dis ; 6(3)2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34564547

RESUMO

X-ray screening is an important tool in tuberculosis (TB) prevention and care, but access has historically been restricted by its immobile nature. As recent advancements have improved the portability of modern X-ray systems, this study represents an early evaluation of the safety, image quality and yield of using an ultra-portable X-ray system for active case finding (ACF). We reported operational and radiological performance characteristics and compared image quality between the ultra-portable and two reference systems. Image quality was rated by three human readers and by an artificial intelligence (AI) software. We deployed the ultra-portable X-ray alongside the reference system for community-based ACF and described TB care cascades for each system. The ultra-portable system operated within advertised specifications and radiologic tolerances, except on X-ray capture capacity, which was 58% lower than the reported maximum of 100 exposures per charge. The mean image quality rating from radiologists for the ultra-portable system was significantly lower than the reference (3.71 vs. 3.99, p < 0.001). However, we detected no significant differences in TB abnormality scores using the AI software (p = 0.571), nor in any of the steps along the TB care cascade during our ACF campaign. Despite some shortcomings, ultra-portable X-ray systems have significant potential to improve case detection and equitable access to high-quality TB care.

4.
Accid Anal Prev ; 144: 105642, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32580063

RESUMO

OBJECTIVE: In Vietnam, motorcycle riders comprise about three-quarters of road traffic fatalities, the most common cause of which is head injuries that can be prevented by wearing a helmet. This study aims to assess helmet-wearing behaviors in Ho Chi Minh City, the largest city in Vietnam. METHODS: Eight rounds of observational studies were conducted in six randomly selected locations between July 2015 and April 2019. Given the multinomial nature of the outcome measure (not wearing a helmet; wearing a substandard helmet; wearing an unstrapped standard helmet; wearing a strapped standard helmet), a multinomial model was developed to estimate the level and trend of helmet use and identify the related individual and environmental factors. FINDINGS: A total of 479,892 motorcycle riders were observed, over 90 % of whom were wearing helmets (range over the eight rounds: 92.5 %-96.0 %). However, the prevalence of correct helmet use (defined as wearing a strapped standard helmet) gradually declined from 80.8 % in round 1-55.6 % in round 8. Results from a multinomial model showed the probability of wearing a strapped standard helmet had declined by 22.4 percentage points from round 3 to round 8 while holding other factors constant (95 % CI: 21.8-23.0). The prevalence of correct use is 11.3 percentage points higher for adults than for children (95 % CI: 10.5-12.1). During the same period, unstrapped standard helmet use increased by 24.5 percentage points (95 % CI: 24.1-24.9); substandard helmet use declined but remained high. CONCLUSION: The upward trend of incorrect helmet wearing behaviors and wearing substandard helmets sends a rallying call for multisectoral interventions.


Assuntos
Dispositivos de Proteção da Cabeça/estatística & dados numéricos , Motocicletas/estatística & dados numéricos , Adolescente , Adulto , Criança , Traumatismos Craniocerebrais/prevenção & controle , Estudos Transversais , Feminino , Dispositivos de Proteção da Cabeça/normas , Humanos , Masculino , Prevalência , Vietnã/epidemiologia
5.
Platelets ; 31(4): 505-512, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-31366263

RESUMO

Thalassemia patients are susceptible to both iron overload and thromboembolism. Deferiprone is an iron chelator that shows an antiplatelet activity and thus may alleviate platelet hyperactivation in thalassemia. Therefore, this study aimed to characterize the inhibitory effects and mechanisms of deferiprone on normal human platelets. The results illustrated that deferiprone inhibited platelet aggregation at the iron chelating concentrations (0.08-0.25 mmol/l). Deferiprone inhibited human platelet aggregation stimulated by arachidonic acid and ADP more potently than epinephrine and collagen, with the IC50 of 0.24 mmol/l and 0.25 mmol/l vs. 3.36 mmol/l and 3.73 mmol/l, respectively. Interestingly, deferiprone significantly inhibited COX-1 activity, with the IC50 of 0.33 mmol/l, and slightly increased cAMP level at the high concentration of 4 mmol/l. Moreover, the results from molecular docking showed that deferiprone interacted closely with key residues in the peroxidase active site of COX-1. These results suggested that deferiprone possessed antiplatelet activity mainly through the inhibition of COX-1 activity.


Assuntos
Plaquetas/efeitos dos fármacos , Ciclo-Oxigenase 1/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Deferiprona/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Difosfato de Adenosina/farmacologia , Adolescente , Ácido Araquidônico/farmacologia , Plaquetas/enzimologia , Plaquetas/metabolismo , AMP Cíclico/metabolismo , Ciclo-Oxigenase 1/química , Ciclo-Oxigenase 1/genética , Deferiprona/química , Humanos , Concentração Inibidora 50 , Pessoa de Meia-Idade , Simulação de Acoplamento Molecular , Adulto Jovem
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