Assessment of crystallite phase, morphology and mechanical properties of concrete reinforced with polyethylene terephthalate (PET)/carbon nanotubes (CNTs)

PET (Polyethylene terephthalate) is a semicrystalline thermoplastic polymer with good chemical resistance, thermal stability, melt mobility, and spinnability. In recent years, the development of nanocomposites with various types of nanomaterials has become a fascinating topic in material science. The polyethylene terephthalate (PET) blended with carbon nanotubes (CNTs) was mixed with concrete to prepare concrete/PET/CNTs nanocomposites. The PET/CNTs were employed as reinforcing material to study the synergistic effect between PET/CNTs and concrete. The impact of PET/CNTs at different ratios on the crystallite phase and morphology of the materials was examined using X-ray diffraction spectroscopy (XRD) and high-resolution scanning electron microscopy (HRSEM), respectively. The mechanical properties were tested using tensile, compression, and flexural measurement. The presence of PET/CNTs changes the orientation of minerals, thus reducing the crystallite sizes in the matrices at a higher amount of PET/CNT. The excellent mechanical strength of the composite materials gradually increased with the increase in concrete/PET/CNTs. The concrete/PET/CNT (1:4) performance was far from rutting due to the excellent compatibility and crosslinking between the reinforcing material and the concrete, thus increasing the mechanical strength and improving the resistance to cracking.

Genetic Structure of Cucumber Mosaic Virus From Natural Hosts in Nigeria Reveals High Diversity and Occurrence of Putative Novel Recombinant Strains

Cucumber mosaic virus (CMV, Bromoviridae: Cucummovirus), one of the most widespread plant viruses with several hosts, causes huge losses in yield quality and quantity. The occurrence of various CMV strains and high genetic diversity within the virus complicate its management. We describe the population structure of CMV in Nigeria using partial RNA1 and RNA3 gene sequences from three natural hosts: pepper (Capsicum annuum), tomato (Solanum lycopersicum), and watermelon (Citrullus lanatus). One hundred and six leaf samples were obtained from 16 locations across Nigeria, and specific primers were used to amplify the two gene fragments using PCR. Twenty-four samples tested positive for CMV using RNA1 primers, and amplicons were sequenced from 12 isolates, revealing 82.94–99.80% nucleotide and 85.42–100% amino acid sequence similarities within the population. The partial RNA3 fragment, corresponding to the complete coat protein (CP) gene, was sequenced from seven isolates, with 95.79–97.90% and 98.62–100% nucleotide and amino acid intrapopulation similarities, respectively. The isolates belonged to subgroup IB and formed distinct phylogenetic clusters in both gene sets, indicating putative novel strains. Recombination signals, supported by phylogenetic inferences, were detected within the RNA1 dataset (P ≤ 0.05) and identified a recombinant isolate within the Nigerian sequences. No recombination was detected within the CP genes. Population genetics parameters established high diversity within the Nigerian population compared to other isolates worldwide, while selection pressure estimates revealed the existence of negative selection in both gene sets. Although CMV subgroup IB strains were postulated to originate from Asia, this study reveals their prevalence across several hosts from different locations in Nigeria. To our knowledge, this is the first comprehensive description of a recombinant CMV subgroup IB isolate from West Africa, which has implications for its robust detection and overall management.

Management of SARS-CoV-2 Infection: Key Focus in Macrolides Efficacy for COVID-19

Macrolides (e.g., erythromycin, fidaxomicin, clarithromycin, and azithromycin) are a class of bacteriostatic antibiotics commonly employed in medicine against various gram-positive and atypical bacterial species mostly related to respiratory tract infections, besides they possess anti-inflammatory and immunomodulatory effects. Coronavirus Disease 2019 (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome of coronavirus 2 (SARS-CoV-2). It was first detected in Wuhan, Hubei, China, in December 2019 and resulted in a continuing pandemic. Macrolides have been extensively researched as broad adjunctive therapy for COVID-19 due to its immunostimulant abilities. Among such class of drugs, azithromycin is described as azalide and is well-known for its ability to decrease the production of pro-inflammatory cytokines, including matrix metalloproteinases, tumor necrosis factor-alpha, interleukin (IL)-6, and IL-8. In fact, a report recently published highlighted the effectiveness of combining azithromycin and hydroxychloroquine for COVID-19 treatment. Indeed, it has been underlined that azithromycin quickly prevents SARS-CoV-2 infection by raising the levels of both interferons and interferon-stimulated proteins at the same time which reduces the virus replication and release. In this sense, the current review aims to evaluate the applications of macrolides for the treatment of COVID-19.

A critical review on geosmin and 2-methylisoborneol in water: sources, effects, detection, and removal techniques

The exposure to geosmin (GSM) and 2-methylisoborneol (2-MIB) in water has caused a negative impact on product reputation and customer distrust. The occurrence of these compounds and their metabolites during drinking water treatment processes has caused different health challenges. Conventional treatment techniques such as coagulation, sedimentation, filtration, and chlorination employed in removing these two commonest taste and odor compounds (GSM and 2-MIB) were found to be ineffective and inherent shortcomings. The removal of GSM and MIB were found to be effective using combination of activated carbon and ozonation; however, high treatment cost associated with ozonation technique and poor regeneration efficiency of activated carbon constitute serious setback to the combined system. Other shortcoming of the activated carbon adsorption and ozonation include low adsorption efficiency due to the presence of natural organic matter and humic acid. In light of this background, the review is focused on the sources, effects, environmental pathways, detection, and removal techniques of 2-MIB and GSM from aqueous media. Although advanced oxidation processes (AOPs) were found to be promising to remove the two compounds from water but accompanied with different challenges. Herein, to fill the knowledge gap analysis on these algal metabolites (GSM and 2-MIB), the integration of treatment processes vis-a-viz combination of one or more AOPs with other conventional methods are considered logical to remove these odorous compounds and hence could improve overall water quality.

Age-Related Effects of Lead Poisoning on Some Haematological Parameters in Adult Wistar Rats

The World Health Organization (WHO) estimates that, about a quarter of the diseases facing mankind today occur due to prolonged exposure to environmental pollution, and that most of these environment-related diseases are however, not easily detected and may be acquired during childhood and manifested later in adulthood. The aim of this work was to evaluate sub-chronic effects of lead poisoning on haematological parameters and some sex hormones, as well as age-related changes on Wistar Rats. Thirty (30) of 3-, 5-, and 7-months old male Wistar rats, were divided into experimental (lead fed) and control (distil water) groups. Haematological parameters were determined, while blood lead concentration was determined using the method of Atomic Absorption Spectrophotometer. There was a significant (P< 0.05) increase (46.00, 46.75, 50.75 vs 14.56, 18.00, 17.60) in blood lead concentration with insignificant (P˃ 0.05) increase in the concentration of WBC counts (12.433, 13.000, 12.250 Vs 12.400, 10.000, 11.250) between the experimental and control groups. Significant decrease in Body Weight (77.43, 107.88, 134.35Vs 130.66, 150.60, 165.62), RBC counts (5.333, 7.000, 6.250 Vs 7.000, 7.500, 7.250), PCV (22.667, 40.00, 35.25 Vs 37.600, 45.5,43.25), Hb (10.000, 12.000, 10.75 Vs 13.200, 13.250, 12.50), MCV (45.333, 54.500, 55.750 Vs 55.400, 59.500, 58.250), MCH levels (15.00016.25016.500 Vs 18.400, 17.750, 17.000), as well as insignificant decrease in platelet counts(410, 373, 341 Vs 437, 313, 384), and MCHC (29.67, 29.75, 30.00 Vs 32.800, 30.25, 29.250). The effect of lead (Pb) on these parameters was observed to be more pronounced in younger animals (P≤0.05). It was concluded that, ingestion of lead acetate produces more physiological derangement in young Wistar Rats.

Potential of using kaolin as a natural adsorbent for the removal of pollutants from tannery wastewater

In the present work, kaolin sample from Gbako Local Government, Niger State, Nigeria was used as an adsorbent for the removal chloride, COD, BOD, sulphate, chromium, cadmium, zinc and the reduction of total alkalinity in tannery wastewater. The kaolin sample was pretreated to enhance its adsorption capacity and then characterized using X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), High Resolution Electron Microscopy (HRSEM), High Resolution Transmission Electron Microscopy (HRTEM), Energy Dispersive Spectroscopy (EDX), Selective Area Electron Diffraction (SAED) and Brunauer Emmett-Teller (BET). The specific surface area, pore volume and pore diameter of the kaolin were 17 m²/g, 0.018 cm³/g and 3.587 nm, respectively. The adsorption methods of the parameters onto the kaolin were investigated as functions of contact time, adsorbent dosage and temperature. Equilibrium isotherms for the adsorption parameters were carried out experimentally and the adsorption data correlated very well with Jovanovic and Redlich-Peterson models. Furthermore, the adsorption kinetics followed the Avrami model. From the results of the study it was established that kaolin from Gbako, Nigeria can serve as an economic, safe and effective natural adsorbent for the pollutants removal from tannery wastewater.

A direct requirement of nuclear factor-kappa B for suppression of apoptosis in ventricular myocytes

Nuclear factor-kappa B (NF-kappa B) is a ubiquitously expressed cellular factor regulated by the cytoplasmic factor inhibitor protein kappa B alpha (I kappa B alpha). Activation of NF-kappa B by cytokines, including tumor necrosis factor-alpha (TNF-alpha), requires the phosphorylation and degradation of I kappa B alpha. An anti-apoptotic role for NF-kappa B has recently been suggested. In the present study, we ascertained whether death-promoting signals and apoptosis mediated by TNF-alpha are suppressed by NF-kappa B in postnatal ventricular myocytes. Stimulation of myocytes with TNF-alpha resulted in a 12.1-fold increase (P < 0.01) in NF-kappa B-dependent gene transcription and DNA binding compared with controls. This was accompanied by a corresponding increase in the NF-kappa B target protein A20 as determined by Western blot analysis. Vital staining revealed that TNF-alpha was not cytotoxic to myocytes and did not provoke apoptosis. Adenovirus-mediated delivery of a nonphosphorylatable form of I kappa B alpha to inactivate NF-kappa B prevented TNF-alpha-stimulated NF-kappa B-dependent gene transcription and nuclear NF-kappa B DNA binding. Importantly, myocytes stimulated with TNF-alpha and defective for NF-kappa B activation resulted in a 2.2-fold increase (P < 0.001) in apoptosis. To our knowledge, the data provide the first indication that a functional NF-kappa B signaling pathway is crucial for suppressing death-promoting signals mediated by TNF-alpha in ventricular myocytes.

Dissociative disorders in the Sultanate of Oman

OBJECTIVE

To study the clinical manifestations and psychosocial aspects of dissociative (conversion) disorders (DD) in the Sultanate of Oman.

METHOD

A retrospective analysis was made of data derived from case records of patients admitted as in-patients to the Sultan Qaboos University Hospital, Oman, over a period of 8 years.

RESULTS

A higher prevalence of DD was noted in Oman compared to western countries. The female preponderance was less marked in Oman. The most common presentations were dissociative convulsions, dissociative motor and dissociative trance disorders. Interpersonal difficulties with family and academic problems were the important identified precipitants.

CONCLUSION

The study highlights the characteristic clinical and psychosocial features of the dissociative phenomena in Oman.

Bcl-2 activates the transcription factor NFkappaB through the degradation of the cytoplasmic inhibitor IkappaBalpha

Nuclear factor kappaB (NFkappaB) is a ubiquitously expressed transcription factor that is regulated by the cytoplasmic inhibitor protein IkappaBalpha. Biological agents such as tumor necrosis factor alpha (TNFalpha), which activate NFkappaB, result in the rapid degradation of IkappaBalpha. Adenoviral-mediated gene transfer of Bcl-2 prevents apoptosis of neonatal ventricular myocytes induced by TNFalpha. In view of the growing evidence that NFkappaB may play an important role in regulating apoptosis, we determined whether TNFalpha and Bcl-2 could modulate the activity of NFkappaB in ventricular myocytes. Stimulation of myocytes with TNFalpha resulted in a 2.1-fold increase (p < 0.001) in NFkappaB-dependent gene transcription and nuclear DNA binding. Similarly, a 1.9-fold increase (p < 0.0002) in NFkappaB-dependent gene transcription was observed in myocytes expressing Bcl-2. Nuclear DNA binding activity of NFkappaB was significantly increased in myocytes expressing Bcl-2, with a concomitant reduction in IkappaBalpha protein level. The Bcl-2-mediated loss of IkappaBalpha could be prevented by the proteasome inhibitor lactacystin, consistent with the notion that the targeted degradation of IkappaBalpha consequent to overexpression of Bcl-2 utilizes the ubiquitin-proteasome pathway. This was further tested in human 293 cells in which the N-terminal region of IkappaBalpha was identified to be an important regulatory site for Bcl-2. Deletion of this region or a serine to alanine substitution mutant at amino acids 32 and 36, which are defective for both phosphorylation and degradation, were more resistant than wild type IkappaBalpha to the inhibitory effects of Bcl-2. To our knowledge, this provides the first evidence for the regulation of IkappaBalpha by Bcl-2 and suggests a link between Bcl-2 and the NFkappaB signaling pathway in the suppression of apoptosis.