Rational design of yolk–shell nanostructures for drug delivery

Yolk–shell nanoparticles (YSNPs) are a new class of hollow nanostructures, and their unique properties can be utilized in drug delivery systems. The recent progress in YSNPs-based carriers is highlighted in drug delivery systems. Doxorubicin hydrochloride, ceftriaxone sodium, and methotrexate are three of the most common drugs that are used in this field. According to the reported studies, the materials used most often as yolk–shells are magnetic nanoparticles and polymers. The used methods for synthesizing a diverse array of YSNPs are classified based on their core structures. Various properties of YSNPs include their high drug-loading capacity, and their ability to decrease drug toxicity and satisfactorily and efficiently release drugs.

The recent progress in yolk–shell nanoparticles (YSNPs) as a new class of hollow nanostructures applied for drug delivery.     

Factors enabling community health workers and volunteers to overcome socio-cultural barriers to behaviour change: meta-synthesis using the concept of social capital

Background

Community-based health workers and volunteers are not just low-level health workforce; their effectiveness is also due to their unique relationship with the community and is often attributed to social capital, an area not well studied or acknowledged in the literature.

Methods

A qualitative meta-synthesis was conducted using the SPIDER framework and based on critical interpretive synthesis. The protocol was registered with PROSPERO, ID = CRD42018084130. This article reports on the qualitative data extracted from the final 33 articles selected from 147 full-text articles on social capital and community-based health systems.

Results

Three constructs were identified that enable community health workers to bring about changes in behaviour in the community: seeing their role as a service or a calling motivated by altruistic values, accompanying community members on their journey and the aim of the journey being empowerment rather than health. Community health workers feel under-resourced to provide for expectations from the community, to fulfil their non-health needs, to meet the expectations of their employers and to be able to deliver health services.

Conclusion

The dichotomy of needs between the community and health services can be resolved if policy makers and programme designers examine the possibility of two cadres of community-based health workforce: full-time workers and part-time volunteers, with clear scopes of practice and supervision. Community health workers would primarily be concerned with task shifting roles demanded by programmes, and volunteers can focus on the wider empowerment-based needs of communities.

     

THE ROLE OF METHIONINE DEFICIENCY IN POLIOVIRUS REPLICATION IN TISSUE CULTURES

The role of methionine in poliovirus infection in HeLa and monkey kidney cells was investigated by using the methionine analogue l-ethionine. In the presence of 2.0 x 10^–3 and 4.0 x 10^–3 moles ethionine, the growth of HeLa and monkey kidney cells was significantly inhibited. Under the same experimental conditions, ethionine had no significant effect on the biosynthesis of two strains of poliovirus (Mahoney and Lansing) in HeLa cells, whereas in primary monkey kidney cells, it markedly inhibited the biosynthesis of the Lansing strain of poliovirus. HeLa cells partly depleted of their intracellular amino acids did not change the rate of viral biosynthesis. The inhibitory effect of ethionine on cell growth and viral biosynthesis was reversed by addition of an excess of l-methionine.     

Prevention and Treatment of Urinary Catheter-Associated Infections

Catheter-associated urinary tract infections (CA-UTIs) are the most common nosocomial infection worldwide. Prolonged catheterization is the most important risk factor for CA-UTIs. As is the case with all device-related infections, the biofilm plays a central role in the pathogenesis of CA-UTIs. The diagnosis is often difficult, given the lack of good diagnostic tests. The most effective way to prevent infection is to limit catheter use and discontinue the catheter when no longer needed. Catheter removal or exchange is also useful in management. This review summarizes and analyzes the results of published studies of CA-UTIs and assesses the role of prevention approaches and management strategies.     

The prevalence of allergic fungal rhinosinusitis in sinonasal polyposis

Allergic fungal sinusitis (AFS) is a noninvasive form of fungal rhinosinusitis with a prevalence of 6–9 % among all rhinosinusitis cases requiring surgery. The fungi causing AFRS have a great diversity and regional variation in the incidence of AFS has been reported worldwide. The aim of this study was to evaluate the prevalence of AFS among rhinosinusitis patients in the north east of Iran. In a prospective cross-sectional study 127 patients with sinonasal polyposis who were candidates for surgery were recruited. All cases were evaluated by sinonasal CT scan, Prick test for common regional allergens, total serum immunoglobulin E (IgE) level, and allergic mucin culture for fungi in suspected cases. Data analyses were done using SPSS version 13.0. Their mean age was 37.4 ± 11.6 years, the male-to-female ratio was 69/58. Eleven patients (9.45 %) met the AFS criteria. Nine cases had a positive culture for Aspergillus specimen and three for Alternaria. Prick test was positive for at least one allergen in 28 cases (22.05 %). The most common allergen was weed. The total IgE level was significantly higher in AFS patients. This study showed the prevalence of AFS among patients with nasal polyposis to be 9.45 %.