Structural,optical and dielectric properties of Cu1.5Mn1.5O4 spinel nanoparticles

In this study, a Cu_1.5Mn_1.5O₄ spinel was successfully synthesized by a sol–gel method at 500 °C for 5 h and characterized by different techniques. X-ray diffraction (XRD), Fourier transformation infrared (FTIR) spectroscopy and Raman spectroscopic analyses confirmed the formation of a spinel cubic structure with the Fd$\bar{3}$m space group. The SEM proves that the grain size of our compound is of the order of 48 nm. Crystallite sizes determined from three estimates are closer to the grain size obtained from the SEM, indicating the single domain nature of the sample. The optical properties of UV-visible spectroscopy for our sample showed that the gap value is equal to 3.82 eV, making our compound a good candidate for optoelectronic applications. For electrical properties, impedance spectroscopy was performed at a frequency range of 40 ≤ frequency ≤ 10⁶ Hz. This suggested hoping conduction due to three theoretical models. The latter can be attributed to the correlated barrier hopping (CBH) model in region I, overlapping large polaron tunneling (OLPT) in region II and non-overlapping small polaron tunneling (NSPT) mechanism in region III. One dielectric relaxation is detected from the dielectric impedance and modulus, attributed to grain contributions. This behavior was confirmed by both Nyquist and Argand''s plots of dielectric impedance at different measuring temperatures.

In this study, a Cu_1.5Mn_1.5O₄ spinel was successfully synthesized by a sol–gel method at 500 °C for 5 h and characterized by different techniques.     

Doxycycline hydrochloride-metronidazole solid lipid microparticles gels for treatment of periodontitis: development,in-vitro and in-vivo clinical evaluation

Objective: To formulate solid lipid microparticles (SLMs) encapsulating doxycycline hydrochloride (DH) and metronidazole (MT) for the treatment of periodontal diseases.

Methods: SLMs were prepared applying hot homogenization method, using different types of lipids and stabilized with various types and concentrations of surfactants. The optimized formula was subjected to freeze-drying followed by incorporation into poloxamer gel. Microbiological and clinical evaluation of the selected SLMs on patients suffering from periodontal diseases was performed.

Results: SLMs could entrap high percentage of both drugs (81.14% and 68.75 % for doxycycline hydrochloride and metronidazole respectively). Transmission electron microscopy images of SLMs showed nearly spherical particles. Freeze-dried SLMs showed satisfactory stability for three months. Combined drugs were molecularly dispersed in SLMs. Incorporation of the freeze-dried SLMs powder in poloxamer gel could control the drugs release for 72 h. In-vivo study revealed effective and safe use of SLMs gel for periodontitis treatment. Significant improvement in both microbiological and clinical parameters was observed as compared to scaling and root planing alone.

Conclusion: The formulated SLMs gel offers an applicable dosage form that can be injected directly into the periodontal pocket as adjunctive to scaling and root planing.     

Association between RANTES polymorphisms and asthma severity among Tunisian children

The chemokine known as RANTES (regulated upon activation, normal T cells expressed and secreted) is an important element for the chemotaxis at the site of allergic inflammation. Many studies have made an interesting link between RANTES polymorphisms and asthma, showing that the variant in the promoter region is associated with high risk of asthma and severe airway obstruction. We conducted a case-control and family study aiming at identifying the relationship between polymorphisms (-28 C/G and -403 G/A) and haplotypes in the RANTES gene with asthma and severity. The results of the case control study suggest an association between alleles level of -28 C/G and -403 G/A promoter polymorphism (p = 0.01) (p = 0.00175) and asthma. Univariate analysis of the RANTES polymorphisms show an increased prevalence of the AC and AG haplotypes in asthmatics (p = 0.014) and (p = 0.015) respectively. Our data suggest that -28 C/G and -403 G/A polymorphisms within the RANTES promoter region play an important role in asthma predisposition and in the severity of airway obstruction.     

Effects of JC virus infection on anti-apoptotic protein survivin in progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a fatal demyelinating disease of the central nervous system resulting from the productive infection of oligodendrocytes by the opportunistic polyomavirus JC virus (JCV). Apoptosis is a host defense mechanism to dispose of damaged cells; however, certain viruses have the ability to deregulate apoptotic pathways to complete their life cycles. One such pathway involves survivin, a member of the inhibitor of apoptosis family, which is abundantly expressed during development in proliferating tissues but should be absent in normal, terminally differentiated cells. Immunohistochemistry performed in 20 cases of PML revealed the presence of survivin in JCV-infected oligodendrocytes and bizarre astrocytes within demyelinated plaques. Survivin up-regulation was also found in oligodendroglial and astrocytic cultures infected with JCV. Cell cycle analysis and DNA laddering demonstrated a significantly lower number of cells undergoing apoptosis on JCV infection compared with noninfected cultures; small interfering RNA inhibition of survivin resulted in a dramatic increase in apoptotic cells in JCV-infected cultures. This is the first report describing the activation of survivin by JCV infection in vitro and in PML clinical cases. These observations provide new insights into the anti-apoptotic mechanisms used by JCV to complete its lytic cycle and may suggest new therapeutic targets for PML.     

Enablers and inhibitors: A review of the situation regarding mHealth adoption in low- and middle-income countries

Objective

The objective of this review is to identify enabling and inhibiting factors for mHealth adoption in low resource settings, by giving emphasis on the stakeholders representing the caregiving side. Another objective of this study is to support implementation agencies (governmental and non-governmental) in designing scalable mHealth interventions.

PLGA-based monolithic filaments prepared by hot-melt extrusion: In-vitro comparative study

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Diallyl sulfide alleviates cisplatin‐induced nephrotoxicity in rats via suppressing NF‐κB downstream inflammatory proteins and p53/Puma signalling pathway

Despite being a potent anticancer drug, nephrotoxicity is an adverse effect which renders the clinical use of cisplatin (Cis) limited. The protective role of diallyl sulfide (DAS); a naturally occurring organo‐sulfide, present in garlic, in cisplatin‐induced nephrotoxicity has been reported earlier. However, the mechanism through which DAS exerts its nephroprotective activity remains elusive. The aim of the current study was to elucidate the possible mechanisms underlying the reno‐protective effect of DAS in cisplatin‐induced nephrotoxicity in rats. DAS was given at 2 dose levels; 50 and 100 mg/kg, orally for 4 consecutive days, starting 1 hour after administration of single dose of cisplatin (3.5 mg/kg, intraperitoneally [i.p.]). The Cis‐induced elevation in serum urea and creatinine, degree of histopathological alterations was significantly ameliorated in cisplatin groups co‐treated with DAS. In addition, DAS significantly restored Cis‐depleted glutathione (GSH) content and superoxide dismutase (SOD) activity and attenuated Cis‐elevated Malondialdehyde (MDA) level. Also, DAS significantly reduced Cis‐increased renal expression of nuclear factor kappa B (NF‐κB) and subsequent pro‐inflammatory mediators; tumour necrosis factor alpha (TNF‐α), interleukin‐1β (IL‐1β), intercellular adhesion molecule‐1 (ICAM‐1) and inducible nitric oxide synthase (iNOS) in kidney tissues. Moreover, co‐treatment with DAS significantly inhibited Cis‐increased caspase‐8 and ‐9 levels. Additionally, DAS significantly mitigated Cis‐induced protein expression of p53, Puma, and Bax while, it significantly restored Cis‐reduced protein expression of Bcl‐xL compared to the Cis group. In conclusion, these results demonstrate that DAS ameliorates cisplatin‐induced nephrotoxicity in rats through enhancement of antioxidant defense, reduction of inflammatory cytokine tissue levels as well as inhibition of apoptosis via p53/Puma signalling pathway.