Brown macroalgae as bio-indicators for heavy metals pollution of Al-Jubail coastal area of Saudi Arabia

Wastes from both industrial and domestic sources, as well as habitat destruction have a substantial impact on the coastal environments. It causes serious problems in many countries and for several seas and oceans which leads to the extinction of several plant and animal species. Many water resources are no longer suitable for drinking or for agriculture as a result of pollution. The main aim of this study was to investigate the efficiency of four brown macroalage as bioindicators for toxic heavy metals (manganese (Mn), copper (Cu), zinc (Zn), arsenite (As), cadmium (Cd), and lead (Pb)) along Al-jubail industrial city coast at Persian Gulf (Saudi Arabia). Brown macroalage samples were collected from three different sites in three time points, January, March and May, 2010. The four collected brown macroalgae were identified as Sargassum angustifolium, Sargassum boveanum, Sargassum latifolium, and Padina gymnospora. The algal samples were cleaned using sea water and distilled water, dried, and the concentrations of various toxic metals were determined. The average concentrations of Mn, Co, Ni and Cd were within the expected limits of un-contaminated areas. However, the results indicate the high level of Zn ion accumulation in all tested brown algae, showing highest concentration in S. angustifolium > P. gymnospora > S. latifolium > S. boveanum with highest Zn concentration of 991 ± 49.1, 988 ± 47.5, 980 ± 44.2, and 911 ± 39.7 µg g-1 dry weights, respectively. In addition, Cu was detected at high concentration of 92.1 ± 3.7 ìg g-1 dry weight in S. boveanum. These results clearly indicate the high pollution levels of Al-jubail industrial city coast with Zn and Cu toxic heavy metals, which is mostly due to uncontrolled disposal of industrial waste into coastal area. Furthermore, the consistency of Zn concentrations in all tested brown algae indicated the efficiency of the tested algae, including P. gymnospora, S. angustifolium, S. latifolium, and S. boveanum, for bioaccumulation and bio-monitoring studies of Zn.Key words: Brown algae, heavy metals, bio-indicators, Sargassum sp., Padina sp

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

Epidemiological characterization of serotype group B Streptococci neonatal infections associated with interleukin-6 level as a sensitive parameter for the early diagnosis

Group B streptococcal infection (Streptococcus agalactiae) is one of the leading causes of life-threatening disease in the early neonatal period, resulting in sepsis, pneumonia, and meningitis. During invasive infections, an excessive release of pro-inflammatory cytokine, such as interleukin-6 (IL-6), thus IL-6 gene is significant, as a diagnostic marker of systemic infection of the newborns. The present study aimed to describe the epidemiology diagnostic of GBS disease in neonatal by phenotypic and genotypic methods. Nine hundred and ninety-six samples were taken at Maternity and Children Hospital, Jeddah, Saudi Arabia for a period of one year (2011–2012). Results indicated that out of 217 infected samples, twenty (9.23.0%) were positive for group B Streptococci bacteria. This study also shows that female infants are more susceptible than males. The level of IL-6 was higher in mothers above 30 years. Twenty positive Streptococci group B isolates showed bands with the cylE gene primers in the border between 228 bp, 267 bp and 50 bp. Molecular detection by Real time polymerase chain reaction was also done to detect the target (Sip gene) encoding the Sip surface immunogenic protein. Specific primers and TaqMan probe were chosen for this purpose. A Real-time PCR method targeting the sip gene of GBS in neonates after delivery has been evaluated. Keywords: Group B Streptococcus (GBS), Interlukin-6 (IL-6) neonatology, Meningitis, cylE, Sip gen

Molecular Epidemiology of Nosocomial Infection: Analysis of chromosomal Restriction Fragment Patterns by Pulsed-Field Gel Electrophoresis

Acinetobacter baumannii is a species of non-fermentative gram-negative coccobacilli commonly found in soil, water and other environmental samples. This bacterium is defined as being strict aerobes, nonmotile, catalase-positive and oxidase-negative. This organism was susceptible to most antibiotics in the 1970s. A. baumannii is an opportunistic pathogen that may be an important threat due to its increasing multidrug resistance and is involved in nosocomial infections that are often severe. The objective of this study was undertaken to elucidate the molecular epidemiology of A. baumannii using the most widely applicable DNA – based typing methods namely Pulsed-Field Gel Electrophoresis (PFGE). These strains comprised isolates from environmental samples, blood, wound, urine, cerebrospinal fluid and tracheal aspirates. PFGE analysis of 81 clinical isolates has been carried out by using CHEF–DR III systems from Bio – Rad and following the protocol of Gautom with some modifications. A 2.00% band tolerance and an optimization of 4.00% were selected for use during comparisons of generated fingerprints or pulsotypes after digestion with Apa I restriction enzyme. Similarity values have been generated using BioNumerics software, cluster analysis was performed by the unweighted pair – group method using arithmetic averages and DNA relatedness was calculated based on Dice coefficient. An interlinkage homology level of 80% between patterns was assumed as the cutoff for defining a close genetic relationship between strains and was used to define the cluster. As per the generated dendogram, isolates were categorized into 18 major groups designated as Strain I to Strain xvIII. Overall, PFGE was able to discriminate the 81 different Acinetobacter baumannii isolates with similarity levels of 63.63%. _________________________________________________king saud universit

Cytogenetic effects of the insecticide (Drago) and herbicide (Fusilade) on the cellular characters of Vicia faba L

Vicia faba L. plants were used to test the combined genotoxic effects of Fusilade (Herbicide) and Drago (Insecticide) and their interaction. Also, germination vigour, vegetative growth and biochemical parameters were used to test the combined physiological effects of two pesticides alone and in combination.To study the cytotoxic effects, the meristem cells in root tips of plant were treated with nine different concentrations (1, 5, 10, 50, 100, 500, 1000, 5000, 10000 ppm) at four different time (3, 6, 12, 24 hrs.). The concentrations of the two pesticides were tested on growth of seeds of Vicia faba L. compared with control where the mean root length of seeds was measured at different times between 24, 48 and 72hrs. Furthermore, after 72h, root degeneration occurred turning the root tips into black colour, which wasn't measurable. lethal concentration LC50% was decreased with the increase in time which caused an increase in percentage of mortality using Probit tables .All the above treatments of two pesticides alone and in combination have been shown to decrease the mitotic index . In the combined pesticides treatments, the decrease in (MI) wasn’t like in the individual pesticide treatments which was less when compared withpesticides alone either herbicide or insecticide at the same concentration and duration. Increase the percentage of mutation frequency in each pesticide alone and the combined (Fus.-Dra.) after 6hrs of treatment whereas at the combined the relation was inversed when compared with control, indicating an antagonistic effect. Also, all treatments used have caused different kinds of mitotic abnormalities and chromosomal aberrations, which were generally as follow: Cmetaphase, chromosome disturbance, stickiness, breaks and fragments, laggard and bridges, multipolar and ring chromosome, micronuclei and binuclear cells. In addition the pesticides have been shown to decrease the protein and DNA and RNA contents below the control level.King Saud Universit

Biochemical and molecular characterization of Haemophilus influenza isolated from Riyadh, Kingdom of Saudi Arabia

The objective of this study focused on the prevalence of Haemophilus influenza to confirm the colonies of H. influenza on the basis of their growth requirements and serotype distribution. This study prepared 80 isolates of H. influenze isolated from five different sources (eye, ear, sputum (SP), lower genital tract (TA), and nasopharyngeal (NPA)) with different ages for infants and elderly persons. The phenotypic characteristics, which included the biotype, serotype, antibiogram and β-lactamase production, were applied by using APINH and minimum inhibitory concentration (MIC). Also, the study focused on the identification of selected serotype using PFGE analysis. The discussion of this study differentiates the age groups occurrence in the isolates, alongside with non-typeable strain versus the typeable ones and their percentages in the sample of isolates. This clustering of most strains in on e PFGE pattern might be explained with the colonel population structure of the encapsulated H. influenza

p16INK4A Represses Breast Stromal Fibroblasts Migration/Invasion and Their VEGF-A-dependent Promotion of Angiogenesis through Akt Inhibition

Stromal fibroblasts, the most abundant and probably the most active cellular component of breast cancer-associated stroma, become active and promote angiogenesis through paracrine effects. However, it still unclear how these processes are regulated. Here, we have shown that down-regulation of the tumor suppressor p16INK4A protein enhances the migration/invasion abilities of breast stromal fibroblasts, which form dendritic network of extensions into matrigel. Furthermore, we present clear evidence that p16INK4A represses the expression/secretion of the proangiogenesis protein vascular endothelial growth factor A (VEGF-A). Consequently, p16INK4A-deficient breast stromal fibroblasts and mouse embryonic fibroblasts enhanced endothelial cell differentiation into capillary-like structures in a paracrine manner. This effect was suppressed by adding bevacizumab, a specific VEGF-A inhibitor. Additionally, p16INK4A-defective mouse embryonic fibroblasts enhanced angiogenesis in breast cancer xenografts in mice. Furthermore, we have shown that p16INK4A suppresses the Akt/mammalian target of rapamycin (mTOR) signaling pathway and its downstream effector hypoxia-inducible factor 1-alpha (HIF-1α), which transactivates VEGF-A. Consequently, Akt inactivation suppressed both the p16INK4A-dependent autocrine effect on fibroblast migration/invasion and the paracrine effect on angiogenesis, showing the important role of this protein kinase in mediating the various effects related to p16INK4A deficiency. These results indicate that p16INK4A is an efficient inhibitor of the migration/invasion abilities of breast stromal fibroblasts and also their paracrine proangiogenic effects, through inhibition of Akt. Therefore, pharmacologic restoration of p16INK4A level in stromal fibroblasts may be exploited as therapeutic strategy to help eradicate tumor cells and/or prevent their recurrence, through suppressing cell non-autonomous procarcinogenic mediators

Bacterial quality control of domestic and imported brands of bottled water in Saudi Arabia

Water is one of the most abundant and essential commodities of man occupying about 70% of the earth's surface and 60% of the human body therefore it should be continuously protected against microbial infections. Also, the mineral content in drinking water should be maintained within the acceptable range. Quality control of drinking water emerged with the invention of bottled drinking water. In this study, samples of bottled drinking water from Saudi markets were compared with tap water samples collected from different areas in Riyadh; both samples were tested for the presence of pathogenic bacteria. The bacterial isolates identified by the Biolog system (Hayward, CA, USA) include Bacillus cereus, Staphylococcus sp. and Pseudomonas aeruginosa in bottled drinking water, whereas tap water was mainly contaminated by P. aeruginosa. Bacterial contamination was highly observed in tap water samples and higher mineral content, determined by inductively coupled plasma-mass spectrometry (ICP-MS) was also observed in tap water. Bacterial cell count determined as CFU/ml was observed in bottled drinking water. Decreased water bacterial number was achieved with the solar disinfection system (SODIS) for one day with direct exposure to sunlight in polyethylene terephthalate (PET) plastic bottles. Thus water considered to be consumed by humans must maintain good microbial and mineral qualities within the acceptable ranges and must undergo effective treatment in order to reduce bacterial count and infection

Ecotoxicity of Ag-nanoparticles on two microalgae, Chlorella vulgaris and Dunaliella tertiolecta

The increasing application of nanotechnology highlights the need to clarify and understand it. In this work, the subacute toxicity of Ag-NPs to the fresh water microalga Chlorella vulgaris and marine microalga Dunaliella tertiolecta were assessed. The effect of Ag-NPs was induced by exposing both algae to increasing concentrations of Ag-NPs (0, 10, 50, 100 and 200 mg/L). Cellular viability and reactive oxygen species (ROS) formation were determined to evaluate the toxic effect of Ag-NPs on algal growth. Superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activities and lipid peroxidation (MDA) levels in the algal cells varied with the concentration of Ag-NPs suspensions and exposure times (up to 8 d). As a result, 100 and 200 mg/L Ag-NPs caused a statistically significant decrease in cell viability, as well as SOD, CAT and POD activities, and a significant increase in ROS formation and MDA levels in tissues (P <0.05), suggesting that the algal cells exposed to these two concentrations of Ag-NPs suffered from oxidative stress. The extent of depletion of antioxidant enzyme activities and the elevation of MDA in Dunaliella tertiolecta was the greatest, indicating that Dunaliella tertiolecta might be the most susceptible to Ag-NP exposure. These results indicated a potential risk from Ag-NPs released into the aqueous environment