Current status of oral and maxillofacial radiology in West Africa

Background

Oral and maxillofacial radiology became the ninth dental specialty recognized by the American Dental Association (ADA) in 1999. This came about following the discovery of X-rays by Wilhelm Conrad Roentgen in 1895 and, 14 days later, the application of X-rays to making dental radiographs by Otto Walkhoff. The purpose of this narrative study was to review the evolution of oral and maxillofacial radiology as a dental specialty in the USA and its recognition as a program of training by the West African College of Surgeons.

Methods

This study was conceptualized as a narrative review of the literature focusing on the history and development of oral and maxillofacial radiology in the USA. It builds a synthesis that describes the recognition of oral and maxillofacial radiology as a specialty of dentistry in West Africa, UK, Japan, and Australia.

Results

The main finding was that oral and maxillofacial radiology became the ninth specialty recognized by the American Dental Association, ADA, in October 13, 1999. On March 20, 2014, the West African College of Surgeons recognized this specialty and granted accreditation for postgraduate training. In the UK, Japan, and Australia, the postgraduate education in oral and maxillofacial radiology has two patterns, namely professional training and academic training.

Conclusions

The primary goal of the postgraduate training curriculum is to train radiologists who are competent to deliver care to patients in any clinical setting, including a dental school, hospital radiology practice, or private practice.

     

Assessing the validity of existing dental sealant quality measures

Background

Although sealants are highly effective in preventing caries in children, placement rates continue to be low. The authors’ goals were to implement and assess the performance of 2 existing sealant quality measures against a manual audit of charts at 4 dental institutions and to identify measurement gaps that may be filled by using data from electronic health records.

Alhagi: A Plant Genus Rich in Bioactives for Pharmaceuticals

Alhagi, a plant genus from family Fabaceae, is widely distributed in many countries of Asia, Australia and Europe. Commonly known as camel thorn, Alhagi has many species famous for feed and folk medicinal uses. Different species of Alhagi such as Alhagi pseudalhagi, A. graecorum, A. sparsifolia, A. kirgisorum, A. maurorum, A. camelorum and A. persarum have been explored for their antioxidant potential and nutritive value along with various medicinal properties. A wide array of pharmacologically active secondary metabolites such as flavonoids, alkaloids (alhacidin and alhacin), steroids, pseudalhagin A, phospholipids and polysaccharides have been reported from different parts of Alhagi species. A broad range of biological activities such as antioxidant, cardiovascular, anti‐ulcer, hepatoprotective, antispasmodic, antidiarrheal, antinociceptive, antipyretic, anti‐inflammatory, anti‐rheumatic, antibacterial and antifungal have been ascribed to different parts of Alhagi. In addition, Alhagi plants are also valued as a rich source of digestible protein and important minerals. This review focuses on the medicinal applications and detailed profile of high‐value bioactive phytochemicals along with pharmacological attributes and therapeutic potential of these multi‐purpose plants. Copyright © 2014 John Wiley & Sons, Ltd.     

Pilot-scale production of a highly thermostable α-amylase enzyme from Thermotoga petrophila cloned into E. coli and its application as a desizer in textile industry

In this study, the industrial applications of a highly thermostable α-amylase as a desizer in the textile industry was evaluated. The cloned gene was expressed in different media (ZBM, LB, ZYBM9, and ZB) with IPTG (isopropyl β-d-1-thiogalactopyranoside) used as an inducer. Lactose was also used as an alternate inducer for the T7 promoter system in E. coli. For the large-scale production of the enzyme, different parameters were optimized. The maximum enzyme production was achieved when the volume of medium was 70% of the total volume of fermenter with a 2.0 vvm air supply and 20% dissolved oxygen at a 200 rpm agitation rate. Under all the optimized conditions, the maximum enzyme production was 22.08 U ml⁻¹ min⁻¹ with lactose (200 mM) as an inducer in ZBM medium. The desizing potential of the purified α-amylase enzyme was calculated with different enzyme concentrations (50–300 U ml⁻¹) at different temperatures (50–100 °C), and pHs (4–9) with varying time intervals (30–120 min). The highest desizing activity was found when 150 U ml⁻¹ enzyme units were utilized at 85 °C and at 6.5 pH for 1 h.

Thermostable recombinant α-amylase was produced in a large scale for the desizing of cotton cloth in the textile industry.     

Convenient pH-responsive removal of Acid Black 1 by green l-histidine/iron oxide magnetic nanoadsorbent from water: performance and mechanistic studies

This study was aimed at developing green histidine-modified Fe₃O₄ nanoparticles (His-MNPs) for the adsorptive removal of Acid Black 1 (AB1) from aqueous solution. The His-MNPs were characterized by atomic force microscopy, scanning electron microscopy-energy dispersive X-ray spectrometry, infra-red spectra and thermogravimetry. These MNPs were spherical (average diameter 11–28 nm) with polydispersity index of 1.40 and about 13% mass coating of histidine. To optimize AB1 adsorption on His-MNPs and understand its mechanism, the influences of different operational variables (pH, adsorbent amount, temperature, initial AB1 concentration, contact time, ionic strength, etc.) on adsorption were examined with adsorption isotherms, kinetics and thermodynamic studies. The AB1 adsorption from water was fast with equilibrium time ≤ 45 min. The adsorption equilibrium was best fitted to the Langmuir isotherm model (q_max = 166.7 mg g⁻¹ at the adsorbent dose of 0.2 g L⁻¹, temperature 30 °C and pH 4). The linearity order for other isotherms was as follows: Dubinin–Radushkevich (D–R) < Temkin < Freundlich. The kinetics of the AB1 adsorption demonstrated the best compliance with the pseudo-second-order model, predominantly controlled by film diffusion as compared to intraparticle diffusion. Thermodynamic parameters (ΔH° and ΔG°) reflected the exothermic and spontaneous adsorption process. The values of ΔG°, ΔH°, activation energy and D–R free adsorption energy were all consistent with the physisorptive removal of AB1. The spectral (electronic and IR) and pH studies further corroborated the mechanism of AB1 removal by His-MNPs. The His-MNPs showed efficient adsorption, easy regeneration and excellent reusability, assisted by their pH-responsive properties. The prepared adsorbent can provide a safe, effective and economical alternative strategy for removing azo dyes from wastewater.

Effective and eco-friendly separation of Acid Black 1 dye from water by electrostatic adsorption onto reusable Histidine-Fe₃O₄ nanoparticles, credited to their pH-responsiveness.     

ASK1-p38 cascaded signal mediates pulmonary microvascular endothelial barrier injury induced by the return of PHSML in rats

The return of post-hemorrhagic shock mesenteric lymph (PHSML) induces pulmonary vascular endothelial barrier dysfunction, which results in acute lung injury. Activation of the apoptosis signal-regulated kinase 1 (ASK1) and p38 mitogen-activated protein kinase (p38 MAPK) pathway has been shown to trigger inflammatory responses. However, whether the ASK1-p38 MAPK pathway is involved in the PHSML-induced pulmonary endothelial barrier dysfunction remains unclear. In the present study, permeability changes of pulmonary capillaries were found in vivo, and activation of the ASK1-p38 MAPK pathway was determined in vitro. PMVEC barrier dysfunction was determined by measuring TEER. Furthermore, junctional and cytoskeletal protein expressions were analyzed. The results showed that hemorrhagic shock led to a marked increase in the permeability of pulmonary capillaries in vivo, which was markedly alleviated by PHSML drainage. In cultured pulmonary microvascular endothelial cells (PMVECs), PHSML reduced the endothelial barrier function accompanied by upregulated p-ASK1 and p-p38 MAPK protein expression, impaired the cytoskeletal protein structure, and down-regulated junction protein expression. These adverse effects were eliminated by applying either Trx1 (ASK1 inhibitor) or SB203580 (p38 MAPK inhibitor). These results indicated that the ASK1-p38 MAPK pathway mediates PHSML-induced pulmonary vascular endothelial barrier dysfunction during hemorrhagic shock.

The return of post-hemorrhagic shock mesenteric lymph (PHSML) induces pulmonary vascular endothelial barrier dysfunction, which results in acute lung injury.     

Facile efficient earth abundant NiO/C composite electrocatalyst for the oxygen evolution reaction

Due to the increasing energy consumption, designing efficient electrocatalysts for electrochemical water splitting is highly demanded. In this study, we provide a facile approach for the design and fabrication of efficient and stable electrocatalysts through wet chemical methods. The carbon material, obtained by the dehydration of sucrose sugar, provides high surface area for the deposition of NiO nanostructures and the resulting NiO/C catalysts show higher activity towards the OER in alkaline media. During the OER, a composite of NiO with 200 mg C can produce current densities of 10 and 20 mA cm⁻² at a bias of 1.45 V and 1.47 V vs. RHE, respectively. Electrochemical impedance spectroscopy experiments showed the lowest charge transfer resistance and the highest double layer capacitance in the case of the NiO/C composite with 200 mg C. The presence of C for the deposition of NiO nanostructures increases the active centers and consequently a robust electrocatalytic activity is achieved. The obtained results in terms of the low overpotential and small Tafel slope of 55 mV dec⁻¹ for non-precious catalysts are clear indications for the significant advancement in the field of electrocatalyst design for water splitting. This composite material based on NiO/C is simple and scalable for widespread use in various applications, especially in supercapacitors and lithium-ion batteries.

Due to the increasing energy consumption, designing efficient electrocatalysts for electrochemical water splitting is highly demanded.     

Synthesis of fluorescent drug molecules for competitive binding assay based on molecularly imprinted polymers

Fluorescent immunosorbent assay (FIA) is very promising for sensitive and selective analysis in bio-medical applications. Here, we proposed an assay, using fluorescent engineering of analytes and the corresponding molecularly imprinted polymers (MIPs) as a plastic antibody. Three drug molecules (metronidazole, zidovudine and lamivudine) were condensed with 9-aminoacridine, using succinic anhydride as a spacer. The target products were characterized with ¹H-NMR, IR and mass spectrometry. UV-vis absorption and fluorescent properties of the fluorophore-labeled drug molecules were investigated. Feasibility of the fluorescent biomimetic immunosorbent assay based on MIPs was demonstrated in the solution. This work will provide sound foundation for the future application in real sample.

Drug molecules (metronidazole, zidovudine and lamivudine) were successfully labelled with a fluorescent reagent and used to develop fluorescent biomimetic immunosorbent assays using molecularly imprinted polymers in the place of natural antibody.