Does Gγ/Aγ ratio and Hb F level influence the severity of sickle cell anaemia

Sickle cell anaemia (SCA) exhibits significant variations in clinical presentation in different populations for which several genetic factors including SCA-associated -and -thalassaemias, G-6-PD deficiency and elevated Hb F level have been implicated as possible ameliorating factors. Saudi Arabia is unique in that mild and severe forms of the disease occur at a high frequency. We investigated the G/A ratio and Hb F level and correlated these values with the severity of SCA. The results showed that Hb F level varies significantly in both groups of patients with no evident correlation with the mild clinical manifestations. However, G/A ratio correlated significantly with the disease severity where a high ratio was observed in patients with the mild and a low ratio in patients with the severe disease. The results are evaluated and discussed in the light of correlation studies and regression analysis.     

Functional EF-Tu with large C-terminal extensions in an E coli strain with a precise deletion of both chromosomal tuf genes

An Escherichia coli strain was constructed in which both chromosomal genes encoding elongation factor (EF)-Tu (tufA and tufB) have been inactivated with precise coding sequence replacements. A tufA gene in an expression vector is supplied as the sole EF-Tu source. By using plasmid replacement, based on plasmid incompatibility, mutant EF-Tu variants with a large C'-terminal extension up to 270 amino acids were studied and proved to be functional in a strain lacking the chromosomal tufA and tufB genes.     

Countdown to 2015: Tracking Maternal and Child Health Intervention Targets Using Lot Quality Assurance Sampling in Bauchi State Nigeria

Background

Improving maternal and child health remains a top priority in Nigeria’s Bauchi State in the northeastern region where the maternal mortality ratio (MMR) and infant mortality rate (IMR) are as high as 1540 per 100,000 live births and 78 per 1,000 live births respectively. In this study, we used the framework of the continuum of maternal and child care to evaluate the impact of interventions in Bauchi State focused on improved maternal and child health, and to ascertain progress towards the achievement of Millennium Development Goals (MDGs) 4 and 5.

Methods

At baseline (2012) and then at follow-up (2013), we randomly sampled 340 households from 19 random locations in each of the 20 Local Government Areas (LGA) of Bauchi State in Northern Nigeria, using the Lot Quality Assurance Sampling (LQAS) technique. Women residents in the households were interviewed about their own health and that of their children. Estimated LGA coverage of maternal and child health indicators were aggregated across the State. These values were then compared to the national figures, and the differences from 2012 to 2014 were calculated.

Results

For several of the indicators, a modest improvement from baseline was found. However, the indicators in the continuum of care neither reached the national average nor attained the 90% globally recommended coverage level. The majority of the LGA surveyed were classifiable as high priority, thus requiring intensified efforts and programmatic scale up.

Conclusions

Intensive scale-up of programs and interventions is needed in Bauchi State, Northern Nigeria, to accelerate, consolidate and sustain the modest but significant achievements in the continuum of care, if MDGs 4 and 5 are to be achieved by the end of 2015. The intentional focus of LGAs as the unit of intervention ought to be considered a condition precedent for future investments. Priority should be given to the re-allocating resources to program areas and regions where coverage has been low. Finally, systematic considerations need to be given to the design of strategies that address the demand for health services.     

Generation and characterization of functional mutants in the translation initiation factor IF1 of Escherichia coli.

Three protein factors IF1, IF2 and IF3 are involved in the initiation of translation in prokaryotes. No clear function has been assigned to the smallest of these three factors, IF1. Therefore, to investigate the role of this protein in the initiation process in Escherichia coli we have mutated the corresponding gene infA. Because IF1 is essential for cell viability and no mutant selection has so far been described, the infA gene in a plasmid was mutated by site-directed mutagenesis in a strain with a chromosomal infA+ gene, followed by deletion of this infA+ gene. Using this approach, the six arginine residues of IF1 were altered to leucine or aspartate. Another set of plasmid-encoded IF1 mutants with a cold-sensitive phenotype was collected using localized random mutagenesis. All mutants with a mutated infA gene on a plasmid and a deletion of the chromosomal infA copy were viable, except for an R65D alteration. Differences in growth phenotypes of the mutants were observed in both minimal and rich media. Some of the mutated infA genes were successfully recombined into the chromosome thereby replacing the wild-type infA+ allele. Several of these recombinants showed reduced growth rate and a partial cold-sensitive phenotype. This paper presents a collection of IF1 mutants designed for in vivo and in vitro studies on the function of IF1.     

Unique Substrate Specificity of SplE Serine Protease from Staphylococcus aureus

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Overexpression and optimization of glutamate decarboxylase in Lactobacillus plantarum Taj‐Apis362 for high gamma‐aminobutyric acid production

Gamma‐aminobutyric acid (GABA) is an important bioactive compound biosynthesized by microorganisms through decarboxylation of glutamate by glutamate decarboxylase (GAD). In this study, a full‐length GAD gene was obtained by cloning the template deoxyribonucleic acid to pTZ57R/T vector. The open reading frame of the GAD gene showed the cloned gene was composed of 1410 nucleotides and encoded a 469 amino acids protein. To improve the GABA‐production, the GAD gene was cloned into pMG36e‐LbGAD, and then expressed in Lactobacillus plantarum Taj‐Apis362 cells. The overexpression was confirmed by SDS‐PAGE and GAD activity, showing a 53 KDa protein with the enzyme activity increased by sevenfold compared with the original GAD activity. The optimal fermentation conditions for GABA production established using response surface methodology were at glutamic acid concentration of 497.973 mM, temperature 36°C, pH 5.31 and time 60 h. Under the conditions, maximum GABA concentration obtained (11.09 mM) was comparable with the predicted value by the model at 11.23 mM. To our knowledge, this is the first report of successful cloning (clone‐back) and overexpression of the LbGAD gene from L. plantarum to L. plantarum cells. The recombinant Lactobacillus could be used as a starter culture for direct incorporation into a food system during fermentation for production of GABA‐rich products.     

Strategies of enzyme immobilization on nanomatrix supports and their intracellular delivery

Abstract

Enzymes are one of the foundations and regulators for all major biological activities in living bodies. Hence, enormous efforts have been made for enhancing the efficiency of enzymes under different conditions. The use of nanomaterials as novel carriers for enzyme delivery and regulating the activities of enzymes has stimulated significant interests in the field of nano-biotechnology for biomedical applications. Since, all types of nanoparticles (NPs) offer large surface to volume ratios, the use of NPs as enzyme carriers affect the structure, performance, loading efficiency, and the reaction kinetics of enzymes. Hence, the immobilization of enzymes on nanomatrices can be used as a useful approach for direct delivery of therapeutic enzymes to the targeted sites. In other words, NPs can be used as advanced enzyme delivery nanocarriers. In this paper, we present an overview of different binding of enzymes to the nanomaterials as well as different types of nanomatrix supports for immobilization of enzymes. Afterwards, the enzyme immobilization on nanomaterials as a potential system for enzyme delivery has been discussed. Finally, the challenges associated with the enzyme delivery using nano matrices and their future perspective have been discussed.

Communicated by Ramasamy H. Sarma     

The Prevalence of unexpected antibodies in Saudi's plasma prior blood transfusion and their association with clinical conditions: A cross-sectional study

Unexpected antibodies, also called irregular antibodies, are not known to exist in a person's serum before testing. This research aims to assess the prevalence of unexpected antibodies and their correlation with several clinical conditions. This cross-sectional prospective study, undertaken from June 2019 to June 2020, included ABO, Rh grouping, cross-matching, and antibody screening. Antibody identification was performed only on patients who tested positive in the screening test. From a total of 9764 participants who were screened for unexpected antibodies, 107 (1.1%) tested positive. The Rh blood group system antibodies were the most frequent, particularly anti-D. There was also a significant correlation between the unexpected antibodies and history of transfusion, pregnancy, and autoimmune diseases as P ≤ 0.05. The most prominent unexpected antibodies in the study belong to the Rh system (Anti-D). Moreover, as a result of the strong correlation between the unexpected antibodies as well as the history of transfusion, pregnancy, and autoimmune diseases, the highest safety criteria must be followed during the transfusion of blood to patients with these clinical conditions.     

Discovery of novel dual inhibitors of receptor tyrosine kinases EGFR and IGF-1R

Novel 4-benzylamino benzo-anellated pyrrolo[2,3-b]pyridines have been synthesized with varied substitution patterns both at the molecular scaffold of the benzo-anellated ring and at the 4-benzylamino residue. With a structural similarity to substituted thieno[2,3-d]pyrimidines as epidermal growth factor receptor (EGFR) inhibitors, we characterized the inhibition of EGFR for our novel compounds. As receptor heterodimerization gained certain interest as mechanism of cancer cells to become resistant against novel protein kinase inhibitors, we additionally measured the inhibition of insulin-like growth factor receptor IGF-1R which is a prominent receptor for such heterodimerizations with EGFR. Structure–activity relationships are discussed for both kinase inhibitions depending on the varied substitution patterns. We discovered novel dual inhibitors of both receptor tyrosine kinases with interest for further studies to reduce inhibitor resistance developments in cancer treatment.     

Adsorption of Phenolic Compounds and Methylene Blue onto Activated Carbon Prepared from Date Fruit Pits

Activated carbon has been prepared from date fruit pits. The carbon, prepared at different burn‐off rates, showed a high uptake of methylene blue. At 92 % burn‐off (weight loss percent of the carbonized pits upon activation), methylene blue uptake was 590 mg/g. With this high capacity, the carbon was then used to study the adsorption of phenol, 2‐nitrophenol, 2,4‐dinitrophenol, and 2,4,6‐trinitrophenol. The prepared activated carbon showed an adsorption capacity better than that of many activated carbons in current use. The experimental adsorption data for the single components were regressed using both Langmuir and Freundlich isotherm models and the fit was generally satisfactory. The experimental adsorption data of the binary system phenol‐2‐nitrophenol were compared with the predicted results using two predictive models: the generalized Langmuir and the IAS models. The data were better represented by the IAS theory than the generalized Langmuir model even though the fit of the experimental data was not adequate.