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81.
Context: Vernonia amygdalina Del. (VA) (Asteraceae) is commonly used to treat hypertension in Malaysia.

Objective: This study investigates the vasorelaxant mechanism of VA ethanol extract (VAE) and analyzes its tri-step FTIR spectroscopy fingerprint.

Materials and methods: Dried VA leaves were extracted with ethanol through maceration and concentrated using rotary evaporator before freeze-dried. The vasorelaxant activity and the underlying mechanisms of VAE using the cumulative concentration (0.01–2.55?mg/mL at 20-min intervals) were evaluated on aortic rings isolated from Sprague Dawley rats in the presence of antagonists.

Results: The tri-step FTIR spectroscopy showed that VAE contains alkaloids, flavonoids, and saponins. VAE caused the relaxation of pre-contracted aortic rings in the presence and absence of endothelium with EC50 of 0.057?±?0.006 and 0.430?±?0.196?mg/mL, respectively. In the presence of Nω-nitro-l-arginine methyl ester (EC50 0.971?±?0.459?mg/mL), methylene blue (EC50 1.203?±?0.426?mg/mL), indomethacin (EC50 2.128?±?1.218?mg/mL), atropine (EC50 0.470?±?0.325?mg/mL), and propranolol (EC50 0.314?±?0.032?mg/mL), relaxation stimulated by VAE was significantly reduced. VAE acted on potassium channels, with its vasorelaxation effects significantly reduced by tetraethylammonium, 4-aminopyridine, barium chloride, and glibenclamide (EC50 0.548?±?0.184, 0.158?±?0.012, 0.847?±?0.342, and 0.304?±?0.075?mg/mL, respectively). VAE was also found to be active in reducing Ca2+ released from the sarcoplasmic reticulum and blocking calcium channels.

Conclusions: The vasorelaxation effect of VAE involves upregulation of NO/cGMP and PGI2 signalling pathways, and modulation of calcium/potassium channels, and muscarinic and β2-adrenergic receptor levels.  相似文献   
82.

Objectives

The present study aimed to evaluate the parents' knowledge, attitudes and practices (KAP) towards the use of antibiotics for childhood upper respiratory tract infections (URTIs), at the Jordanian University Hospital.

Methods

This was a cross-sectional study. During the study period, 1301 parents of young children completed a validated – structured questionnaire.

Results

Gaps in common knowledge related to antibiotics and their use were noted among participants. Nearly half of respondents believed that antibiotics are void from adverse effects, while 72.4% of them believed that a child should be given an antibiotic if it develops fever, even though 60% they were aware that most URTIs were viral in nature. Parents reported that they administered antibiotics to children without medical advice most of the time for various causes, including using a previously prescribed antibiotic for a similar illness (27.1%), or based on pharmacist's recommendation (23.8%).

Conclusion

The results demonstrated the need for educational interventions to increase the awareness of parents about antibiotics to reduce inappropriate use and its consequences.  相似文献   
83.

Background:

Health system reforms in many countries have shown that the delivery of integrated primary health care services according to family medicine is the most efficient approach to achieve universal health coverage. In Tunisia, the issue is therefore the capacity of our health system to integrate a care approach based on family practice.

Aim:

To assess the preparedness to implement family medicine in our country

Methodology:

this is a qualitative study carried out over a period of 9 months during the year 2017.Based on a WHO protocol addressing the 13 pillars of family practice, our study explores health policy context, actors (using interviews with key informants at national, regional and local level) and health content.

Results:

Family practice model is a strategic priority in Tunisia. However, this political recognition suffers from a lack of operationalization, in relation with continuing medical training, registration of patients and families by doctors, referral system, minimum package of essential care/ essential drugs and quality of care monitoring as well as community involvement..

Conclusion:

Our situation analysis reveals that the delivery of integrated care based on family practice model; enforce to adopt a comprehensive and operational health policy that goes beyond the academic aspects.  相似文献   
84.
Recently, the fruits of Hylocereus polyrhizus, known as red dragon fruit, have received much attention from growers worldwide. However, there is little toxicological information regarding the safety of repeated exposure to these fruits. The present study evaluated the potential toxicity of a methanol extract of H. polyrhizus fruit after acute and subchronic administration in rats. In the acute toxicity study, single doses of fruit extract (1250, 2500 and 5000 mg/kg) were administered to rats by oral gavage, and the rats were then monitored for 14 days. In the subchronic toxicity study, the fruit extract was administered orally to rats at doses of 1250, 2500 and 5000 mg/kg/day for 28 days. There was no mortality or signs of acute or subchronic toxicity. There was no significant difference in body weight, relative organ weight or hematological parameters in the subchronic toxicity study. Biochemical analysis showed some significant changes, including creatinine, globulin, total protein and urea levels. No abnormality of internal organs was observed between treatment and control groups. The lethal oral dose of the fruit extract is more than 5000 mg/kg and the no-observed-adverse-effect level (NOAEL) of the extract for both male and female rats is considered to be 5000 mg/kg per day for 28 days.  相似文献   
85.
BACKGROUND AND OBJECTIVE: Digoxin is a known substrate of ATP-binding cassette B1 (ABCB1/MDR1). The results of studies on the association between ABCB1 polymorphisms and digoxin kinetics, however, remain contradictory. Almost all studies were small and involved only single dose kinetics. The goal of this study was to establish ABCB1 genotype effect on digoxin blood concentrations in a large cohort of chronic digoxin users in a general Dutch European population. METHODS: Digoxin users were identified in the Rotterdam Study, a prospective population-based cohort study of individuals aged 55 years and above. Digoxin blood levels were gathered from regional hospitals and laboratories. ABCB1 single nucleotide polymorphisms (SNPs) 1236C-->T, 2677G-->T/A, and 3435C-->T were assessed on peripheral blood DNA using Taqman assays. We studied the association between the ABCB1 genotypes and haplotypes, and digoxin blood levels using linear regression models adjusting for potential confounders. RESULTS: Digoxin serum levels and DNA were available for 195 participants (56.4% women, mean age 79.4 years). All three ABCB1 variants were significantly associated with serum digoxin concentration (0.18-0.21 microg/l per additional T allele). The association was even stronger for the 1236-2677-3435 TTT haplotype allele [0.26 mug/l (95% CI 0.14-0.38)], but absent for other haplotypes (CGC allele considered referent), suggesting an interaction of SNPs in a causal haplotype instead of individual SNP effects. CONCLUSION: We found that the common ABCB1 1236C-->T, 2677G-->T, and 3435C-->T variants and the associated TTT haplotype were associated with higher digoxin serum concentrations in a cohort of elderly European digoxin users in the general population.  相似文献   
86.
Morphine is known to prevent the development of cell-mediated immune (CMI) responses and enhance expression of the CCR5 receptor in monocyte macrophages. We undertook a study to determine the effect of morphine on the neuropathogenesis and immunopathogenesis of simian immunodeficiency virus (SIV) infection in Indian Rhesus Macaques. Hypothetically, the effect of morphine would be to prevent the development of CMI responses to SIV and to enhance the infection in macrophages. Sixteen Rhesus Macaques were divided into three experimental groups: M (morphine only, n = 5), VM (morphine + SIV, n = 6), and V (SIV only, n = 5). Animals in groups M and VM were given 2.5 mg/kg of morphine sulfate, four times daily, for up to 59 weeks. Groups VM and V were inoculated with SIVmacR71/17E 26 weeks after the beginning of morphine administration. Morphine prevented the development of enzyme-linked immunosorbent spot-forming cell CMI responses in contrast to virus control animals, all of which developed CMI. Whereas morphine treatment had no effect on viremia, cerebrospinal fluid viral titers or survival over the time course of the study, the drug was associated with a tendency for greater build-up of virus in the brains of infected animals. Histopathological changes in the brains of animals that developed disease were of a demyelinating type in the VM animals compared to an encephalitic type in the V animals. This difference may have been associated with the immunosuppressive effect of the drug in inhibiting CMI responses.  相似文献   
87.
Chronic particulate matter less than 2.5 μm in diameter (PM2.5) exposure can leave infants more susceptible to illness. Our objective is to estimate associations of the chronic PM2.5 exposure with infant bronchiolitis and otitis media (OM) clinical encounters. We obtained all first time bronchiolitis (n = 18,029) and OM (n = 40,042) clinical encounters among children less than 12 and 36 months of age, respectively, diagnosed from 2001 to 2009 and two controls per case matched on birthdate and gestational age from the Pregnancy to Early Life Longitudinal data linkage system in Massachusetts. We applied conditional logistic regression to estimate odds ratios (OR) and confidence intervals (CI) per 2-μg/m3 increase in lifetime average satellite based PM2.5 exposure. Effect modification was assessed by age, gestational age, frequency of clinical encounter, and income. We examined associations between residential distance to roadways, traffic density, and infant bronchiolitis and OM risk. PM2.5 was not associated with infant bronchiolitis (OR = 1.02, 95% CI = 1.00, 1.04) and inversely associated with OM (OR = 0.97, 95% CI = 0.95, 0.99). There was no evidence of effect modification. Compared to infants living near low traffic density, infants residing in high traffic density had elevated risk of bronchiolitis (OR = 1.23, 95% CI = 1.14, 1.31) but not OM (OR = 0.98, 95% CI = 0.93, 1.02) clinical encounter. We did not find strong evidence to support an association between early-life long-term PM2.5 exposure and infant bronchiolitis or OM. Bronchiolitis risk was increased among infants living near high traffic density.  相似文献   
88.
89.
90.
Background: Primary healthcare (PHC) is essential for equitable access and cost-effective healthcare. This makes PHC a key factor in the global strategy for universal health coverage (UHC). Implementing PHC requires an understanding of the health system under prevailing circumstances, but for most countries, no data are available.

Objectives: This paper describes and analyses the health systems of Bahrain, Egypt, Lebanon, Qatar, Sudan and the United Arab Emirates, in relation to PHC.

Methods: Data were collected during a workshop at the WONCA East Mediterranean Regional Conference in 2017. Academic family physicians (FP) presented their country, using the WONCA framework of 11 PowerPoint slides with queries of the country demographics, main health challenges, and the position of PHC in the health system.

Results: All six countries have improved the health of their populations, but currently face challenges of non-communicable diseases, aging populations and increasing costs. Main concerns were a lack of trained FPs in community settings, underuse of prevention and of equitable access to care. Countries differed in the extent to which this had resulted in coherent policy.

Conclusion: Priorities were (i) advocacy for community-based PHC to policymakers, including the importance of coordination of healthcare at the community level, and UHC to respond to the needs of populations; (ii) collaboration with universities to include PHC as a core component of every medical curriculum; (iii) collaboration with communities to improve public understanding of PHC; (iv) engagement with the private sector to focus on PHC and UHC.  相似文献   
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