Evaluation of shear bond strength and SEM observation of all-in-one self-etching primer used for bonding of fissure sealants

OBJECTIVES: To evaluate and compare enamel shear bond strength of an all-in-one self-etching primer (Prompt L-Pop) to regular acid etch material when bonded to two-fissure sealant systems (Concise and Dyract Seal). METHOD AND MATERIALS: Forty newly extracted non-carious first permanent molars were embedded in a Teflon mold. The teeth were divided into four groups and each consisted of ten specimens. The bonding surfaces were treated with either Prompt L-Pop as recommended by the manufacturer or etched with phosphoric acid. After 24 hours of water storage, the specimens were evaluated for shear bond strength using an Instron testing machine. Scanning electron microscope (SEM) examinations were carried out to evaluate the failure sites of the sealants. RESULTS: The mean shear bond strengths using Prompt L-Pop were Concise: 23.46 MPa and Dyract Seal: 20.34 MPa. These values were higher than and statistically different from those of Dyract Seal (9.99 MPa) and Concise (8.85 MPa) when phosphoric acid was used. The failure was predominantly of the adhesive type. The SEM examination showed the failure of debonding was predominantly related to the type of etching systems used rather than the type of fissure sealants. CONCLUSION: The use of the all-in-one self-etching adhesive Prompt L-Pop improves the mean enamel shear bond strength of fissure sealants.     

Food Insecurity,Dietary Diversity,and Coping Strategies in Jordan during the COVID-19 Pandemic: A Cross-Sectional Study

The 2019 coronavirus disease (COVID-19) is an emerging respiratory infection with severe impacts on the nutritional status of the worldwide population. This cross-sectional study was conducted to assess the food insecurity, dietary diversity, and food-related coping strategies in Jordan during the pandemic using an online, self-administered questionnaire. Among the 740 adults who completed the survey, the prevalence of food security was 84.1%, whereas 2% and 13.9% were moderately and severely food-insecure, respectively. The determinants of food insecurity were educational level, monthly income, marital status, availability of health insurance, and type of residence. In addition, food insecurity was significantly higher among the participants who consumed two or fewer meals per day (p = 0.015). Moreover, an acceptable food consumption score was shown among 76.2% of the participants, and the remaining participants were at borderline (14.1%) or had poor scores (9.7%), with a significant association between food insecurity and food consumption scores (p < 0.001). The food-related coping strategies studied were significantly associated with food insecurity at both levels (p < 0.001) and were more evident in the severely food-insecure group. These findings highlight the adverse effects of COVID-19 restrictions on nutritional status, especially among food-insecure households, which might reduce food accessibility due to economic difficulties.     

Efficacy of epidural dexamethasone versus fentanyl on postoperative analgesia

Purpose  

Dexamethasone has analgesic, anti-inflammatory, and antiemetic effects. This prospective, randomized, double-blind, controlled study was designed to evaluate the efficacy of adding dexamethasone versus fentanyl to epidural bupivacaine on postoperative analgesia.     

Photodynamic efficacy of hypericin targeted by two delivery techniques to hepatocellular carcinoma cells

The photocytotoxic effect of hypericin (Hyp) targeted by two different delivery techniques, namely, liposomes and anti-hepatocyte specific antigen (anti-HSA) was investigated. Optical absorption and steady-state fluorescence were used to analyze the conjugation of Hyp with anti-HSA model and to evaluate the encapsulation capacity and drug release in a liposome model. Particle size and thermal analysis of the prepared liposomes were performed using laser-light scattering and differential scanning calorimetry (DSC), respectively. Viability study of HepG2 cells exposed to Hyp in the two delivery systems, in the dark and following visible light irradiation, was performed in comparison to free Hyp. The intracellular uptake and localization of Hyp in HepG2 cells were analyzed by means of spectrofluorometry and fluorescence microscopy. Spectroscopic measurements demonstrated that Hyp binds to anti-HSA in its monomeric form. The photocytotoxic effect of Hyp depended clearly on the form of Hyp administered, either in free form, loaded into liposomes or conjugated with anti-HSA. While liposomes loaded with Hyp (Lip-Hyp) did not induce significant phototoxicity, both free Hyp or anti-HSA-Hyp inflicted substantial cell mortality, after photoirradiation. The intracellular uptake of Lip-Hyp by HepG2 cells was estimated to be 20% less compared to free Hyp or anti-HSA-Hyp. In spite of the equal uptake of both free Hyp and anti-HSA-Hyp, HepG2 cells demonstrated a relatively higher mortality with anti-HSA-Hyp compared to free Hyp.     

The effects of selective cyclooxygenase-2 inhibitors, celecoxib and rofecoxib, on experimental colitis induced by acetic acid in rats

Several mediators may be involved in the pathogenesis of inflammatory bowel disease, as well as in experimental colitis. The present work was conducted to investigate the effects of the two selective cyclooxygenase-2 inhibitors, celecoxib and rofecoxib, on experimentally induced colitis in rats. Rectal instillation of acetic acid was used to induce the colitis. Acetic acid treatment caused haemorrhagic diarrhoea and weight loss in rats. Celecoxib (5 mg/kg) or rofecoxib (2.5 mg/kg), when given twice daily by the oral route, reduced the degree of haemorrhagic diarrhoea and the weight loss produced. In addition, they produced a significant reduction in the degree of colonic injury, the rise in myeloperoxidase (MPO) levels, total nitric oxide synthetase (NOS) activity, platelet-activating factor (PAF), histamine levels and prostaglandin E2 levels. In contrast, there was a significant increase in the levels of reduced glutathione (GSH). Thus, the findings of the present study provide evidence that selective cyclooxygenase-2 inhibitors may be beneficial in patients with inflammatory bowel disease.     

Ultrahigh verapamil-loaded controlled release polymeric beads using superamphiphobic substrate: D-optimal statistical design,in vitro and in vivo performance

Controlled-release multiparticulate systems of hydrophilic drugs usually suffer from poor encapsulation and rapid-release rate. In the present study, ultra-high loaded controlled release polymeric beads containing verapamil hydrochloride (VP) as hydrophilic model drug were efficiently prepared using superamphiphobic substrates aiming to improve patient compliance by reducing dosing frequency. Superamphiphobic substrates were fabricated using clean aluminum sheets etched with ammonia solution and were treated with 1.5% (w/v) perfluorodecyltriethoxysilane (PFDTS) alcoholic solution. The effect of the main polymer type (lactide/glycolide (PLGA) 5004A, PLGA 5010, and polycaprolactone (PCL)), copolymer (Eudragit RS100) content together with the effect of drug load on encapsulation efficiency (EE%) and in vitro drug release was statistically studied and optimized via D-optimal statistical design. In vivo pharmacokinetic study was carried out to compare the optimized system relative to the market product (Isoptin^®). Results revealed that superamphiphobic substrates were successfully prepared showing a rough micro-sized hierarchical structured surface upon observing with scanning electron microscope and were confirmed by high contact angles of 151.60?±?2.42 and 142.80°±05.23° for water and olive oil, respectively. The fabricated VP-loaded beads showed extremely high encapsulation efficiency exceeding 92.31% w/w. All the prepared systems exhibited a controlled release behavior with Q12?h ranging between 5.46 and 95.90%w/w. The optimized VP-loaded system composed of 150?mg (1.5% w/v) PCL without Eudragit RS100 together with 160?mg VP showed 2.7-folds mean residence time compared to the market product allowing once daily administration instead of three times per day.     

Formulation and optimization of orodispersible tablets of flutamide

The present study aimed to formulate orodispersible tablets of flutamide (FTM) to increase its bioavailability. Orodispersible tablets were prepared by direct compression technique using three different approaches namely; super-disintegration, effervescence and sublimation. Different combined approaches were proposed and evaluated to optimize tablet characteristics. Sodium starch glycolate (SSG) was used as the superdisintegrant. The prepared powder mixtures were subjected to both pre and post compression evaluation parameters including; IR spectroscopy, micromeritics properties, tablet hardness, friability, wetting time, disintegration time and in-vitro drug release. IR studies indicated that there was no interaction between the drug and the excipients used except Ludipress. The results of micromeritics studies revealed that all formulations were of acceptable to good flowability. Tablet hardness and friability indicated good mechanical strength. Wetting and dispersion times decreased from 46 to 38 s by increasing the SSG concentration from 3.33 to 6.66% w/w in tablets prepared by superdisintegration method. The F8 formulation which was prepared by combined approaches of effervescence and superdisintegrant addition gave promising results for tablet disintegration and wetting times but failed to give faster dissolution rate. The incorporation of 1:5 solid dispersion of FTM: PEG 6000 instead of the pure drug in the same formulation increased the drug release rate from 73.12 to 96.99% after 15 min. This increase in the dissolution rate may be due to the amorphization of the drug during the solid dispersion preparation. The presence of the amorphous form of the drug was shown in the IR spectra.     

Influenza a common viral infection among Hajj pilgrims: time for routine surveillance and vaccination

BACKGROUND: The annual Hajj pilgrimage to Mecca, Saudi Arabia brings over two million people to a small confined area. Respiratory tract infection is the most common disease transmitted during this period. For most of the etiologic agents of upper respiratory tract infections, no vaccine or prophylaxis is available, except for influenza. Yearly influenza vaccination of high-risk groups is recommended, but no special recommendations are available for those performing the Hajj or other similar large congregational activities. Viral surveillance studies are being carried out through more than 100 centers around the world to identify newly emerging viruses. Saudi Arabia is not one of those centers and no routine surveillance takes place. METHODS: Five hundred Hajj pilgrims presenting with upper respiratory tract symptoms from different parts of the world were screened by way of a throat swab for viral culture, including influenza A and B, parainfluenza, respiratory syncytial virus (RSV), adenovirus, herpes simplex virus (HSV), and enteroviruses. Information was collected on age, sex, nationality, smoking habits and upper respiratory tract symptoms. Vaccination status for influenza and meningococcus was obtained by self-declaration, since most pilgrims did not have their vaccination cards with them. Only those with symptoms including at least fever, reported by the patient to be >38.3 degrees C, and/or sore throat were included. Pilgrims with any other symptoms, especially myalgia and fatigue alone, were excluded, since many of the physical chores during the pilgrimage may contribute to such symptoms. RESULTS: Fifty-four patients (10.8%) had positive viral throat cultures. Of these, 27 (50%) were influenza B, 13 (24.1%) were HSV, 7 (12.9%) were RSV, 4 (7.4%) were parainfluenza, and 3 (5.6%) were influenza A. No enteroviruses or adenoviruses were detected, and no multiple infections were detected. Only 22 (4.7%) pilgrims received the influenza vaccine. When the results are applied to the total number of pilgrims in 2003, an estimate of 24,000 cases of influenza is obtained. CONCLUSION: The findings from this study suggest a high incidence of influenza as a cause of upper respiratory tract infection among pilgrims, estimated to be 24,000 cases per Hajj season, excluding those becoming ill from contact with Hajj pilgrims returning home. They also indicate a very low vaccination rate for the influenza vaccine; as well as poor knowledge of its existence. Continued surveillance during the Hajj pilgrimage is necessary. The influenza vaccine should be a priority for those attending the Hajj pilgrimage, and should also be considered for antiviral prophylaxis.     

Synthesis of new imidazolyl acetic acid derivatives with anti-inflammatory and analgesic activities

We synthesized 2-(4-(4-fluorobenzylidene)-2-(4-fluorophenyl) 5-oxo-4,5-dihydroimidazol-1-yl) acetic acid 3. Chlorination afforded the chloro derivative 4, which reacted with different amines and hydrazine to afford compounds 5–8. Pyrazole, pyrazolone, and thiazolidinone derivatives were also synthesized from Imidazol-1-ylacetic acid hydrazide 8 to give compounds 9–12. Compounds were then evaluated for their anti-inflammatory activity against carrageenan-induced rat paw edema and their analgesic activity using the writhing test in albino mice. Compounds 5, 9, 10, 12 exhibited maximum anti-inflammatory activity, and all the compounds inhibited writhing, with 10 and 12 being two times more effective than the reference standard.     

Dietary fish oil,and to a lesser extent the fat-1 transgene,increases astrocyte activation in response to intracerebroventricular amyloid-β 1–40 in mice

Objectives: Increases in astrocytes and one of their markers, glial fibrillary acidic protein (GFAP) have been reported in the brains of patients with Alzheimer’s disease (AD). N-3 polyunsaturated fatty acids (PUFA) modulate neuroinflammation in animal models; however, their effect on astrocytes is unclear.

Methods: Fat-1 mice and their wildtype littermates were fed either a fish oil diet or a safflower oil diet deprived of n-3 PUFA. At 12 weeks, mice underwent intracerebroventricular infusion of amyloid-β 1-40. Astrocyte phenotype in the hippocampus was assessed at baseline and 10 days post-surgery using immunohistochemistry with various microscopy and image analysis techniques.

Results: GFAP increased in all groups in response to amyloid-β, with a greater increase in fish oil-fed mice than either fat-1 or wildtype safflower oil-fed mice. Astrocytes in this group were also more hypertrophic, suggesting increased activation. Both fat-1- and fish oil-fed mice had greater increases in branch number and length in response to amyloid-β infusion than wildtype safflower animals.

Conclusion: Fish oil feeding, and to a lesser extent the fat-1 transgene, enhances the astrocyte activation phenotype in response to amyloid-β 1-40. Astrocytes in mice fed fish oil were more activated in response to amyloid-β than in fat-1 mice despite similar levels of hippocampal n-3 PUFA, which suggests that other fatty acids or dietary factors contribute to this effect.