Helicobacter pylori Western cagA genotype in Egyptian patients with upper gastrointestinal disease

Background: Infection with Helicobacter pylori (H. pylori) causes persistent gastritis that may progress to fatal gastric cancer. The cytotoxin-associated gene A protein (CagA), encoded by the cytotoxin-associated gene A (cagA) is the main virulence factor associated with more severe clinical outcomes. It is further divided into Western-type CagA and East Asian-type CagA. The East Asian-type CagA induces more cytoskeleton changes and is more likely to be associated with gastric cancer.Aim of the study: In the current study we aimed to identify the most prevalent H. pylori cagA genotype among Egyptian patients suffering from dyspepsia and to examine its possible correlation with the associated clinical condition.Patients and methods: Four biopsies were obtained from the antrum and angularis from each of 113 adult patients, who underwent upper endoscopy at the Endoscopy Unit, Theodor Bilharz Research Institute (TBRI) Hospital for the analysis of H. pylori by rapid urease test and detection of 16S rRNA. Nested PCR assay was used to determine cagA genotype.Results: Sixty (53.1%) dyspeptic patients were found infected with H. pylori. Although Egypt has a high prevalence of H. pylori infection, low prevalence of cagA was detected (26.5%). Western type cagA is the predominant type (62.5%) while East Asian type was not detected and others (37.5%) remain uncharacterized. Western-genotype cagA genotype was found in 80% of patients with peptic ulcer disease and 40% of patients with gastritis.Conclusion: Absence of the more virulent East Asian cagA genotype, which is the strongest risk factor for gastric carcinogenesis, may explain the very low gastric cancer rate among Egyptian population compared to other parts of the world. This finding demands further molecular studies using whole genome sequencing and more samples to determine the exact uncharacterized cagA genotype to identify the actual risk in developing gastroduodenal diseases in Egypt.Keywords: Helicobacter pylori, Endoscopic findings, Western type cagA, East-Asian cagA, Peptic ulcer, Gastriti

HYPOLIPIDEMIC AND ANTI-FATTY LIVER EFFECTS EXERTED BY STANDARDIZED PUNICA GRANATUM L. PEEL EXTRACT IN HEPG2 CELL-LINE AND HIGH-FAT DIET-INDUCED MICE

Objective: Pomegranate, (Punica granatum L., Lythraceae) peel has concentrated amounts of lipid-lowering elements that demonstrated, in various hoary and recent studies, their effects against obesity and hyperlipidemia, which involves elevated rates of lipid and lipoprotein levels in blood and increases risks of cardiovascular diseases.We aim to study expression modulation of genes involved in lipid metabolism by the impact of standardized pomegranate peel extract (PPE) in a comprehensive research on human liver cells and experimental mice.Methods: Using reverse-transcription real-time PCR, an in vitro study harnessing HepG2 cell line was conducted to determine the hyperlipidemia-related gene expression profiles and cytotoxic effects upon treatment with PPE. In another complementary in vivo study, male C57BL/6J mice were fed a high-fat diet (HFD) or an HFD supplemented with PPE for 14 d to define the expression of lipid metabolism related genes that control obesity. Fatty liver proportions were also estimated after treatment.Results: Higher mRNA expression of LDL receptor (LDL-R) and down-regulation of sterol regulatory element-binding protein (SREBF-2), (SRBEP-1c), Fatty acid synthase (FAS) and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) upon PPE treatment in HepG2 cell line were significantly recorded. In vivo study indicated significant weight reduction of body and liver, besides amelioration of fatty liver state detected by histological analysis. Moreover, the reverse-transcription real-time PCR assay demonstrated suppression (FAS) expression and up regulation of hormone sensitive lipase (HSL) in mice isolated liver and white adipose tissues.Conclusion: Our study manages to affirm the hypolipidemic and anti-fatty liver influence of Punica granatum L. peel extract, reflected by molecular evaluation above and beyond other physiological assays.Keywords: Pomegranate, Peel extract, Hyperlipidemia, LDLR, SREBP, FAS, HMGCR, HS

Detection of Helicobacter pylori vacA, cagA and iceA1 virulence genes associated with gastric diseases in Egyptian patients

Background: Helicobactor pylori (H. pylori) virulence markers would be useful to predict peptic ulcer disease (PUD) or gastric cancer.Aim: In Egypt, since inadequate data are present regarding H. pylori virulence–related genes in different age group patients with gastro-duodenal diseases, it becomes crucial to study the clinical status of cagA, vacA and iceA1 genotypes of H. pylori strains recovered from patients with dyspepsia.Subjects and methods: The study included 113 dyspeptic patients who were exposed to upper gastrointestinal endoscopic examination. Four antral biopsies were obtained from each patient for the analysis of H. pylori infection by rapid urease test and detection of 16S rRNA.Results: Sixty (53.1%) patients were confirmed to be infected with H. pylori. Upon endoscopy, gastritis was revealed in 27 patients (45%) and10 patients (16.7%) had PUD. Of the 60 H. pylori strains, 39 (65%) had at least one virulence gene. Six different genotypic forms were recognized; vacA (9/60), iceA1 (1/60), vacA/cagA (7/60), vacA/iceA1 (13/60), vacA/cagA/iceA1 (8/60) only one of cagA/iceA type and we could not detect cagA. The overall vacA, iceA1and cagA genes identified were 61.6%, 38.8%, 26.6% respectively, by PCR-based molecular testing. The vacA gene status was highly significant related to gastritis patient (P 0.036). The vacA s1m1 and s2m2 alleles were significantly found in 50% of H. pylori infected patients with PUD and with gastritis 57.1% respectively (P 0.01).Conclusion: In conclusion, the main genotype combinations in the studied Egyptian patients were; vacAs2m2/iceA1, vacAs1m1/cagA, mostly associated with gastritis, and vacAs1/cagA/icA, mainly in PUD. The less virulent (s2, s2m2) H. pylori genotypes were found in patients aged over 43 years

Synthesis, physicochemical characterization, toxicity and efficacy of a PEG conjugate and a hybrid PEG conjugate nanoparticle formulation of the antibiotic moxifloxacin

Antibiotic resistance is increasing at such an alarming rate that it is now one of the greatest global health challenges. Undesirable toxic side-effects of the drugs lead to high rates of non-completion of treatment regimens which in turn leads to the development of drug resistance. We report on the development of delivery systems that enable antibiotics to be toxic against bacterial cells while sparing human cells. The broad-spectrum fluoroquinolone antibiotic moxifloxacin (Mox) was successfully conjugated to poly(ethylene glycol) (PEG) which was further encapsulated into the hydrophobic poly(3- caprolactone) (PCL) nanoparticles (NPs) with high efficiency, average particle size of 241.8 4 nm and negative zeta potential. Toxicity against erythrocytes and MDBK cell lines and drug release in human plasma were evaluated. Hemocompatibility and reduced cytotoxicity of the PEG–Mox and PCL(PEG– Mox) NPs were demonstrated in comparison to free Mox. Antimicrobial activity was assessed against drug sensitive and resistant: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae. The antibacterial activity of Mox was largely maintained after conjugation. Our data shows that the toxicity of Mox can be effectively attenuated while, in the case of PEG–Mox, retaining significant antibacterial activity. At the conditions employed in this study for antimicrobial activity the encapsulated conjugate (PCL(PEG–Mox) NPs) did not demonstrate, conclusively, significant antibacterial activity. These systems do, however, hold promise if further developed for improved treatment of bacterial infections.The National Research Foundation of South Africa and the Ministry of Higher Education and Scientific Research, Egypt.http://pubs.rsc.org/en/journals/journalissues/raam2021Chemistr

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance.

Investment in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing in Africa over the past year has led to a major increase in the number of sequences that have been generated and used to track the pandemic on the continent, a number that now exceeds 100,000 genomes. Our results show an increase in the number of African countries that are able to sequence domestically and highlight that local sequencing enables faster turnaround times and more-regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and illuminate the distinct dispersal dynamics of variants of concern-particularly Alpha, Beta, Delta, and Omicron-on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve while the continent faces many emerging and reemerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Functionalized GO nanoplatelets with folic acid as a novel material for boosting humidity sensing of chitosan/PVA nanocomposites for active food packaging

International audienceHumidity sensing materials play a pivotal role for serving as the essence of moisture sensors to trap surrounding water molecules through hydrophilic interaction, chemical bonding, or hydrogen bonds, therefore enhancing the sensor conductivity. Thus, this work addresses a highly efficient humidity sensing material based on folic acid (FA) functionalized graphene oxide (GO) which was prepared for consolidating inside chitosan (CS)/polyvinyl alcohol (PVA) (80/20) blend by the solvent casting approach. The structure of GO and its decoration were ratified by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and UV–vis spectroscopies. Three GO-FA contents (i.e., 10, 20, and 30 vol%) were utilized to fabricate the renewable CS/PVA nanosensors. The morphology of fabricated sensors was characterized by XRD and scanning electron microscopy (SEM). SEM images showed that the miscibility and dispersibility of GO-FA nanoplatelets in the CS/PVA matrix are better at 10 and 20 vol%, although the tensile strength increased to 69.40 MPa for the nanocomposite film containing 30 vol% GO-FA compared to the blank specimen. Moreover, other investigations such as Raman spectroscopy and antibacterial activities were performed on the CS/PVA sensors. The humidity sensing properties were carried out over a broad range of relative humidity from (7–97% RH) and frequency (100 Hz-100 kHz). The data revealed that 1 kHz was considered to be the optimum frequency. Furthermore, the obtained outcomes from humidity-sensing tests at 1 kHz showed that the sensor C10 had higher sensitivity with ultrafast response/recovery times (2.6 s/3.5 s) compared to other nanosensors, to be used in intelligent food packaging and preservation

Synthesis, physicochemical characterization, toxicity and efficacy of a PEG conjugate and a hybrid PEG conjugate nanoparticle formulation of the antibiotic moxifloxacin

Antibiotic resistance is increasing at such an alarming rate that it is now one of the greatest global health challenges. Undesirable toxic side-effects of the drugs lead to high rates of non-completion of treatment regimens which in turn leads to the development of drug resistance. We report on the development of delivery systems that enable antibiotics to be toxic against bacterial cells while sparing human cells