ABSTRACT
The current research study evaluated the health and environmental risks issues associated with potentially toxic elements (PTEs) in the complex terminal aquifer located in the Algerian desert. The methods used included principal component and cluster (dendrogram) analysis to estimate source of ions and contamination. Various indices such as the Heavy Metal Pollution Index (HPI), Metal Index, hazard quotient, hazard index (HI), and cancer risk (CR) were applied to assess both environmental and human health risks. Furthermore, the Monte Carlo method was applied for probabilistic assessment of carcinogenic and non-carcinogenic risks through oral and dermal exposure routes in both adults and children. The results revealed that approximately 16% of the samples fell within the low pollution category (HPI < 100), indicating relatively lower levels of heavy metal contamination. However, the remaining 84% of the samples exhibited high pollution levels, indicating a significant presence of heavy metal pollutants in the northeastern part of the investigated area. The calculated average risk index (RI) for the collected samples was 18.99, with a range from 0.03 to 103.21. This indicates that a large portion, 82% of the samples, could cause low ecological risk (RI < 30), whereas the remaining 18% indicate a significant environmental pollution risk. The HI for oral ingestion showed that adults had HI values ranging from 0.231 to 1.54, while children exhibited higher values, ranging from 0.884 to 5.9 (Fig. 5a). For dermal exposure, HI values in adults ranged from 2.71E-07 to 8.74E-06 and in children, from 2.18E-06 to 7.03E-05. These findings highlight the potential non-carcinogenic risks associated with oral exposure to PTEs and underscore the increased vulnerability of children to metals such as Fe, Mn, Pb, and Cr. Most samples showed CR exceeding 1 × 10-4 for chromium (Cr) and lead (Pb), indicating a significant vulnerability to carcinogenic effects in both children and adults.
Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Algeria , Risk Assessment/methods , Humans , Metals, Heavy/analysis , Metals, Heavy/toxicity , Water Pollutants, Chemical/analysis , Water Quality , Environmental Monitoring/methods , Child , Adult , Monte Carlo Method , Environmental Exposure/adverse effects , Environmental Exposure/analysis , Groundwater/chemistry , Groundwater/analysisABSTRACT
Objective: 1) To evaluate the contribution of the GeneXpert® MTB/RIF (GX) test in the diagnosis of pulmonary and extra-pulmonary tuberculosis compared to culture. 2) To compare the rifampicin results resistance obtained by GX with the phenotypic sensitivity test. Materials and methods: Retrospective study carried out over a period of five years, from May 2017 to June 2022 at the microbiology laboratory of the Central army Hospital Mohamed Seghir Nekkache, Algiers (Algeria). The pulmonary and extrapulmonary clinical specimens were collected, cultivated, tested by GX PCR and direct examination by Ziehl-Neelsen staining. The study of sensitivity to antituberculosis drugs was performed according to the proportion method on liquid medium Bactec MGIT 960 (or on solid medium Lowenstein-Jensen at the Algerian Pasteur Institute). Results: 310 samples were included in the final analysis of the study, of which 156 were of pulmonary origin and 154 of extrapulmonary origin. Mycobacterium tuberculosis complex (MTBC) was detected in 95 samples from 88 tuberculosis patients (sex ratio 2,03 and middle age 37 years) with 49 cases of pulmonary tuberculosis and 39 cases of extra-pulmonary tuberculosis. For 2 cases, the GX was positive while the culture was negative and for 11 cases, the GX was negative while the culture was positive. Thus, in our study and compared to culture, GX showed an overall sensitivity of 88.2%, a specificity of 98.6%, a positive predictive value (PPV) of 96.4% and a negative predictive value (NPV) of 95.2%. The analysis of the data according to the type of samples, the sensitivity, specificity, PPV and NPV of GX for the pulmonary and extrapulmonary samples were 96.3% vs. 77.0%, 98.0% vs. 99.1%, 96.2% vs. 96.5% and 98.0% vs. 92.7% respectively. The sensitivity of GX for disco-vertebral, lymph node, meningeal and pleural tuberculosis were 100%, 90.0%, 71.4% and 57.1% respectively. The sensitivity of GX for pulmonary tuberculosis compared to microscopy was 96% vs. 68%. The comparison of the results of detection of resistance to rifampicin by GX and by phenotypic methods showed perfect agreement. Discussion and conclusion: A good sensitivity of GX compared to microscopy was revealed. The GX is a useful tool for the diagnosis of pulmonary tuberculosis, especially in smear-negative cases. The sensitivity of GX in extrapulmonary tuberculosis varied depending on the location of the infection. A negative result by GX does not exclude tuberculosis and cases of resistance to RIF detected by GX must be confirmed by phenotypic method.
Subject(s)
Antibiotics, Antitubercular , Mycobacterium tuberculosis , Rifampin , Humans , Algeria , Rifampin/pharmacology , Retrospective Studies , Female , Male , Adult , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/genetics , Middle Aged , Antibiotics, Antitubercular/pharmacology , Drug Resistance, Bacterial/genetics , Young Adult , Tuberculosis/diagnosis , Tuberculosis/microbiology , Tuberculosis/drug therapy , Molecular Diagnostic Techniques/methods , Microbial Sensitivity Tests , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/drug therapy , Tuberculosis, Pulmonary/microbiology , Aged , Adolescent , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Multidrug-Resistant/microbiology , Sensitivity and SpecificityABSTRACT
BACKGROUND: Lung cancer is the most commonly diagnosed cancer and the leading cause of cancer-related death in men in Algeria. Little is known about the characteristics of lung cancer in Algeria. This study aimed to determine the clinicopathological characteristics and prognosis of non-small cell lung cancer (NSCLC) patients in Algeria. METHODS: This retrospective study was performed on 269 pathologically confirmed cases of NSCLC at the Benbadis University Hospital of Constantine (2015-2023). Of these, 95 patients were included in the survival analysis. The clinicopathological and outcome data were investigated based on the patients' medical records. RESULTS: This study showed male predominance with sex ratio of 5.7, with a mean age of 61.8 years. Histologically, 67.3% of cases had adenocarcinoma (ADC) and 22.7% squamous cell carcinoma (SCC). ADC and SCC occurred more frequently in female (p = 0.02) and male (p = 0.003) patients, respectively. Smoking was estimated at 82.2% in men. Over 28% were non-smokers, of which 50.7% were women, and presented at younger age (p = 0.04). Most of our patients (75.5%) have an advanced stage at diagnosis. Around 70% of patients underwent chemotherapy (CT) as first-line treatment, with medians diagnostic and treatment delays of 4 and 1 months, respectively. The median overall survival (mOS) was estimated at 10.3 and 6.7 months in I-III and IV stages, respectively. Other factors that negatively impact OS were age > 65 years (p = 0.01), and the presence of symptoms (p = 0.005) and comorbidity (p = 0.004) in stage IV, and delayed treatment (p = 0.03) and receiving CT alone (p = 0.03) in stages I-III cases. Medians progression free survival (mPFS) in stage IV, III, and II patients were 4.1, 5.2, and 8.3 months, respectively, and negatively affected by the comorbidity (stage IV, p = 0.03) and receiving CT alone (stages II-III, p = 0.03). CONCLUSIONS: NSCLC presents at an early age and advanced stage in Algerian patients. ADC is the most frequent histological subtype and smoking remains the most important risk factor in men. Furthermore, the prognostic factors affecting survival are stage, age, comorbidity, symptoms, and treatment. Thus, tobacco control, early detection program, and access to novel therapies may be the best strategies to reduce NSCLC morbidity and mortality.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Male , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/epidemiology , Carcinoma, Non-Small-Cell Lung/therapy , Female , Middle Aged , Algeria/epidemiology , Retrospective Studies , Lung Neoplasms/pathology , Lung Neoplasms/mortality , Lung Neoplasms/epidemiology , Lung Neoplasms/therapy , Prognosis , Aged , Adult , Neoplasm Staging , Aged, 80 and over , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/epidemiology , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/therapy , Survival AnalysisABSTRACT
The study focuses on current pollution in the Saïda basin, a semi-arid region in north-western Algeria. By analyzing sediments, the study provides interesting results on urban pollution and its environmental impact. The research consists of two main phases, each addressing different aspects of pollution. In the first phase, different pollution indicators are used to analyze heavy metals and organic pollutants in urban drainage sediments. The results are compared with sediment quality guidelines, regulatory thresholds, and local and international references. Most of the metallic contaminants exceed the toxicity levels established by the continental crust and sediment quality guidelines, suggesting an anthropogenic origin. In addition, contamination indices show significant accumulation. In this context, the results highlight the importance of accumulation and transport processes in urban sediments. Hydrological parameters significantly influence heavy metal distribution mechanisms. Remarkable variations between copper (Cu) and lead (Pb) suggest a combined or singular source during transport. Conversely, chromium (Cr), nickel (Ni), and iron (Fe) are mainly derived from natural lithological sources. Cadmium (Cd) is associated with anthropogenic sources related to the agricultural use of phosphate fertilizers, whereas zinc (Zn) is mainly derived from physical corrosion processes. In the second phase, a combined descriptive and multivariate statistical analysis examines the mobility and distribution of heavy metals and their relationships with organic matter (OM) over time. Pronounced temporal variations in Cd, Zn, and Cu concentrations are attributed to human activities. Strong correlations exist between OM and cobalt (Co), Cu and Pb, confirming the ability of OM to adsorb these metals under specific geochemical conditions associated with waste disposal. Conversely, Zn, Cd, Cr, and Ni show weak or negative correlations with OM, suggesting diverse sources, including potential agricultural, industrial, and natural origins. The dendrogram confirms the existence of previously identified contaminant groups, suggesting common sources and potential co-occurrence patterns. This analysis highlights the role of the drainage network as a physico-chemical reactor in the mobilization of contaminants. It underlines the importance of sediment interactions in urban pollution processes. Finally, recommendations are proposed to ensure effective pollution control and remediation. PRACTITIONER POINTS: Useful information on pollution and its environmental impact is provided by the analysis of sediments in the urban basin of Saida (NW-Algeria). The results of this study indicate high levels of heavy metals in the sediments, in excess of toxicity limits, and evidence of anthropogenic sources. Temporal variations in metal concentrations indicate the influence of human activities. The study has made it possible to identify the sources, to understand the mobility and distribution, and to control the contamination by heavy metals in the urban sediments. Drainage system serves as a pathway for dispersing contaminants.
Subject(s)
Environmental Monitoring , Geologic Sediments , Metals, Heavy , Water Pollutants, Chemical , Metals, Heavy/analysis , Algeria , Geologic Sediments/chemistry , Water Pollutants, Chemical/analysis , CitiesABSTRACT
Introduction: preterm births continue to be the main cause of infant and child mortality as well as sensory-motor disabilities and neurodevelopmental difficulties worldwide. The rate of preterm births has been rising, in particular in Algeria. The purpose of this study is to determine the frequency of preterm births in the Oran Wilaya and to identify risk factors. Methods: we used data from a multicentre cross-sectional study carried out in all Public Maternity Hospitals in the Oran Wilaya (13). The study included parturient women who had given birth to a live and/or stillborn child (with birthweights ≥500 g), whose gestational age was greater than or equal to 24-36 weeks of amenorrhoea. Mothers´ demographic, medical and socio-behavioural factors were recorded. Logistic regression was used to study predictors of prematurity. Results: preterm birth rate was 9.9% (45/452). The average age of patients was 30.4±6 years; multiple pregnancies accounted for 2.2% of births. Factors related to prematurity were the risk of premature labour (aOR=4.68; 95% CI: 2.27-9.64), the lack of clinical monitoring of pregnancy (OR=2.83; CI 95%: 1.83-6.05) and gestational hypertension (aOR = 3.69, 95% CI: 1.83-8.8). Conclusion: the rate of preterm births is in line with the rate observed in neighbouring countries. The study identified predictive factors, some of which are already targeted by the national perinatal program. However, it is essential to continue to lead efforts to improve the monitoring and management of pregnancies and premature births at all levels of care.
Subject(s)
Gestational Age , Premature Birth , Humans , Algeria/epidemiology , Female , Cross-Sectional Studies , Pregnancy , Risk Factors , Premature Birth/epidemiology , Adult , Young Adult , Infant, Newborn , Hypertension, Pregnancy-Induced/epidemiology , Pregnancy, Multiple/statistics & numerical data , Obstetric Labor, Premature/epidemiology , Hospitals, Maternity/statistics & numerical data , AdolescentABSTRACT
Transmissible spongiform encephalopathies (TSEs) are a fatal neurogenerative disease that include Creutzfeldt-Jakob disease in humans, scrapie in sheep and goats, bovine spongiform encephalopathy (BSE), and several others as well as the recently described camel prion disease (CPD). CPD originally was documented in 3.1% of camels examined during an antemortem slaughterhouse inspection in the Ouargla region of Algeria. Of three individuals confirmed for CPD, two were sequenced for the exon 3 of the prion protein gene (PRNP) and were identical to sequences previously reported for Camelus dromedarius. Given that other TSEs, such as BSE, are known to be capable of cross-species transmission and that there is household consumption of meat and milk from Camelus, regulations to ensure camel and human health should be a One Health priority in exporting countries. Although the interspecies transmissibility of CPD currently is unknown, genotypic characterization of Camelus PRNP may be used for predictability of predisposition and potential susceptibility to CPD. Herein, eight breeds of dromedary camels from a previous genetic (mitochondrial DNA and microsatellites) and morphological study were genotyped for PRNP and compared to genotypes from CPD-positive Algerian camels. Sequence data from PRNP indicated that Ethiopian camels possessed 100% sequence identity to CPD-positive camels from Algeria. In addition, the camel PRNP genotype is unique compared to other members of the Orders Cetartiodactyla and Perissodactyla and provides an in-depth phylogenetic analysis of families within Cetartiodactyla and Perissodactyla that was used to infer the evolutionary history of the PRNP gene.
Subject(s)
Camelus , Prion Diseases , Animals , Camelus/genetics , Prion Diseases/genetics , Prion Diseases/veterinary , Algeria/epidemiology , Prion Proteins/genetics , Genotype , Phylogeny , Prions/geneticsABSTRACT
Introduction: Pharmacogenetic markers, such as the ATP Binding Cassette (ABCB1) and cytochrome P450 (CYP) 3A5 enzymes, play a crucial role in personalized medicine by influencing drug efficacy and toxicity based on individuals' or populations' genetic variations.This study aims to investigate the genetic polymorphisms of CYP3A5 (rs776746) and ABCB1 (rs1045642) in the West Algerian population and compare the genotypes and allelic distributions with those of various ethnic groups. Methods: The study involved 472 unrelated healthy subjects from the Western Algerian population. DNA genotyping was performed using TaqMan allelic discrimination assay. The variants in our population were compared to those in other ethnic groups available in the 1000 Genomes Project. Genotype and allele frequencies were calculated using the chi-square test and the Hardy-Weinberg equilibrium (HWE). Results: The minor allele frequencies were found to be 0.21 for CYP3A5 6986A and 0.34 for ABCB1 3435T. These frequencies were similar to those observed in North African populations, while notable differences were observed in comparison to certain Caucasian and African populations. Conclusion: The difference in the allelic and genotypic distribution of these polymorphisms emphasize the need for dose adjustments in drugs metabolized by CYP3A5 and transported by ABCB1 to optimize treatments outcomes.
Subject(s)
ATP Binding Cassette Transporter, Subfamily B , Cytochrome P-450 CYP3A , Gene Frequency , Genotype , Polymorphism, Single Nucleotide , Humans , Cytochrome P-450 CYP3A/genetics , ATP Binding Cassette Transporter, Subfamily B/genetics , Algeria , Male , Female , Adult , Pharmacogenetics , Middle Aged , Black People/genetics , Alleles , Young AdultABSTRACT
Toxoplasma gondii is one of the world's most widespread polyxenic protozoan parasites that affect all warm-blooded animals, including humans. This survey aims to study, for the first time in Algeria, the seroprevalence of Toxoplasma infection in zoo animals. The study included eight animal species of which 54 serum samples were collected from 30 Australian goats (Capra hircus), four bulls (Bos taurus), one dromedary (Camelus dromedarius), three cuffed sheep (Ammotragus lervia), seven donkeys (Equus asinus), one pony (Equus ferus), four bearded horses (Equus ferus caballus) and four rabbits (Oryctolagus cuniculus). The presence of antibodies to T. gondii was determined using the ID Screen® Toxoplasmosis Indirect Multispecies ELISA kit (IDVet, Grabels, France). A total of 8/54 (14.8%) samples were seropositive, including 5/28 (17.9%) males and 3/26 (11.5%) females. The seroprevalence was 6.7%, 50%, 25% and 75% in Capra hircus, Bos Taurus, Equus ferus caballus, and Oryctolagus cuniculus, respectively. No cases were observed in Camelus dromedarius, Ammotragus lervia, Equus asinus, and Equus ferus. This study indicates, for the first time in Algeria, the seroprevalence of T. gondii in zoo animals.
Subject(s)
Animals, Zoo , Antibodies, Protozoan , Toxoplasma , Toxoplasmosis, Animal , Animals , Toxoplasmosis, Animal/epidemiology , Toxoplasmosis, Animal/parasitology , Algeria/epidemiology , Seroepidemiologic Studies , Animals, Zoo/parasitology , Toxoplasma/immunology , Toxoplasma/isolation & purification , Female , Male , Antibodies, Protozoan/blood , Goats , Cattle , Enzyme-Linked Immunosorbent Assay/veterinary , Horses/parasitology , Rabbits/parasitology , SheepABSTRACT
BACKGROUND: Ticks are hematophagous arthropods acting as important vectors for several microorganisms. Ticks have an important role in the epidemiology of numerous diseases from a public health standpoint. In Algeria, knowledge of tick-borne associated microorganisms is limited. This paper aimed to investigate the presence of microorganisms in Ixodes ticks in Ain Kerma El Tarf region. MATERIALS AND METHODS: Ticks were collected from the environment using the flagging method in El Hannachir, Ain kerma (El Tarf province), conserved in 70% ethanol, and morphologically identified. DNA was individually isolated from the ticks and screened for the presence of Piroplasmids and Hepatozoon spp., Borrelia spp., Spotted fever group Rickettsia, Bartonella spp., Mycoplasma spp., Anaplasmataceae, Anaplasma phagocytophilum, Francisella tularensis. RESULTS: Adult ticks of the genus Ixodes (n = 51) were collected. Due to their pronounced morphological resemblance, the sampled ticks are referenced as: I. ricinus/ I.inopinatus (n = 51, 26 males, 25 females). The following pathogens were identified in the tested ticks: Borrelia lusitaniae (n = 17; 33.33%), Rickettsia monacensis (n = 10; 19.60%), and R. helvetica (n = 5; 9.80%). In addition, five ticks (9.80%) were found to be coinfected with Borrelia lusitaniae and R. monacensis/ heletica. All ticks were negative for Piroplasmids and Hepatozoon spp., Bartonella spp., Mycoplasma spp., Anaplasmataceae, Anaplasma phagocytophilum and Francisella tularensis. CONCLUSION: Questing Ixodes ticks from Algeria are carriers of various pathogens, with Borrelia lusitaniae posing a potential risk in the country.
Subject(s)
Borrelia , Ixodes , Animals , Algeria/epidemiology , Ixodes/microbiology , Ixodes/parasitology , Borrelia/isolation & purification , Borrelia/genetics , Female , MaleABSTRACT
Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is the first-line method for the rapid identification of most cultured microorganisms. As for Streptomyces strains, MALDI-TOF MS identification is complicated by the characteristic incrustation of colonies in agar and the strong cell wall of Actinomycetes cells requiring the use of alternative protein extraction protocols. In this study, we developed a specific protocol to overcome these difficulties for the MALDI-TOF MS identification of Actinomycetes made on solid medium. This protocol includes incubation of colony removed from agar plate with the beta-agarase enzyme, followed by a mechanical lysis and two washes by phosphate buffer and ethanol. Twenty-four Streptomyces and two Lentzea strains isolated from Algerian desertic soils were first identified by 16S rRNA sequencing as gold standard method, rpoB gene was used as a secondary gene target when 16S rRNA did not allow species identification. In parallel the isolates were identified by using the MALDI-TOF MS protocol as reported. After the expansion of the database with the inclusion of this MSPS, the strains were analyzed again in MALDI Biotyper, and all were identified. This work demonstrates that the rapid identification of Actinomycetes can be obtained without protein extraction step frequently used in MALDI-TOF mass spectrometry with this type of microorganisms.
Subject(s)
Actinobacteria , RNA, Ribosomal, 16S , Soil Microbiology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , RNA, Ribosomal, 16S/genetics , Algeria , Actinobacteria/isolation & purification , Actinobacteria/genetics , Actinobacteria/classification , Actinobacteria/chemistry , DNA, Bacterial/genetics , Streptomyces/isolation & purification , Streptomyces/genetics , Streptomyces/classification , Streptomyces/chemistry , Bacterial Proteins/genetics , DNA-Directed RNA Polymerases/genetics , Culture Media/chemistry , Sequence Analysis, DNA , Bacteriological Techniques/methods , Glycoside HydrolasesABSTRACT
Industrial effluents pose a serious environmental problem, because they contain toxic contaminants mainly heavy metals that are the most dangerous to humans, animals, plants, and the environment in general. Phytoremediation using macrophytes is an adopted technique for the environment decontamination due to its efficiency and cost-effectiveness. The present study aims to highlight the capabilities of macrophytes to remove heavy metals from wastewater of Biskra region (Algeria). The methodology consists of filling out the filters planted with Arundo donax and Phragmites australis with raw industrial wastewater, then recovering decontaminated water after 15 days to assess removal of lead, copper, zinc, and iron. Both plants had shown a good efficiency for the removal of metals loaded in wastewater eliminating about 94 to 98% of initial concentration. In addition, calculated bioaccumulation factor (BAF) had confirmed the accumulation of heavy metals in different parts of experimental plants; recorded values of BAF > 1 allowed the consideration of Arundo donax and Phragmites australis as good hyper-accumulator plants. Obtained results confirm the efficiency of phytoremediation technology using macrophytes for the wastewater treatment in particular and the environment decontamination in general.
Subject(s)
Biodegradation, Environmental , Metals, Heavy , Poaceae , Waste Disposal, Fluid , Wastewater , Water Pollutants, Chemical , Metals, Heavy/analysis , Metals, Heavy/metabolism , Wastewater/chemistry , Water Pollutants, Chemical/metabolism , Water Pollutants, Chemical/analysis , Waste Disposal, Fluid/methods , Algeria , Industrial WasteABSTRACT
Northeastern Algeria boasts numerous hot springs, yet these hydrothermal sites remain largely unexplored for their microbial ecology. The present study explores the bacterial abundance and diversity within two distinct Algerian hot springs (Hammam Saïda and Hammam Debagh) and investigates the link between the prevailing bacteria with geochemical parameters. High-throughput 16S rRNA gene sequencing of water and sediment samples revealed a bacterial dominance of 99.85-91.16% compared to Archaea (0.14-0.66%) in both springs. Interestingly, Saïda hot spring, characterized by higher temperatures and sodium content, harbored a community dominated by Pseudomonadota (51.13%), whereas Debagh, a Ca-Cl-SO4 type spring, was primarily populated by Bacillota with 55.33%. Bacteroidota displayed even distribution across both sites. Additional phyla, including Chloroflexota, Deinococcota, Cyanobacteriota, and Chlorobiota, were also present. Environmental factors, particularly temperature, sodium, potassium, and alkalinity, significantly influenced bacterial diversity and composition. These findings shed light on the interplay between distinct microbial communities and their associated geochemical properties, providing valuable insights for future research on biogeochemical processes in these unique ecosystems driven by distinct environmental conditions, including potential applications in bioremediation and enzyme discovery.
Subject(s)
Bacteria , Hot Springs , RNA, Ribosomal, 16S , Hot Springs/microbiology , Algeria , Biodiversity , ArchaeaABSTRACT
Water plays a pivotal role in socio-economic development in Algeria. However, the overexploitations of groundwater resources, water scarcity, and the proliferation of pollution sources (including industrial and urban effluents, untreated landfills, and chemical fertilizers, etc.) have resulted in substantial groundwater contamination. Preserving water irrigation quality has thus become a primary priority, capturing the attention of both scientists and local authorities. The current study introduces an innovative method to mapping contamination risks, integrating vulnerability assessments, land use patterns (as a sources of pollution), and groundwater overexploitation (represented by the waterhole density) through the implementation of a decision tree model. The resulting risk map illustrates the probability of contamination occurrence in the substantial aquifer on the plateau of Mostaganem. An agricultural region characterized by the intensive nutrients and pesticides use, the significant presence of septic tanks, widespread illegal dumping, and a technical landfill not compliant with environmental standards. The critical situation in the region is exacerbated by excessive groundwater pumping surpassing the aquifer's natural replenishment capacity (with 115 boreholes and 6345 operational wells), especially in a semi-arid climate featuring limited water resources and frequent drought. Vulnerability was evaluated using the DRFTID method, a derivative of the DRASTIC model, considering parameters such as depth to groundwater, recharge, fracture density, slope, nature of the unsaturated zone, and the drainage density. All these parameters are combined with analyses of inter-parameter relationship effects. The results show a spatial distribution into three risk levels (low, medium, and high), with 31.5% designated as high risk, and 56% as medium risk. The validation of this mapping relies on the assessment of physicochemical analyses in samples collected between 2010 and 2020. The results indicate elevated groundwater contamination levels in samples. Chloride exceeded acceptable levels by 100%, nitrate by 71%, calcium by 50%, and sodium by 42%. These elevated concentrations impact electrical conductivity, resulting in highly mineralized water attributed to anthropogenic agricultural pollution and septic tank discharges. High-risk zones align with areas exhibiting elevated nitrate and chloride concentrations. This model, deemed satisfactory, significantly enhances the sustainable management of water resources and irrigated land across various areas. In the long term, it would be beneficial to refine "vulnerability and risk" models by integrating detailed data on land use, groundwater exploitation, and hydrogeological and hydrochemical characteristics. This approach could improve vulnerability accuracy and pollution risk maps, particularly through detailed local data availability. It is also crucial that public authorities support these initiatives by adapting them to local geographical and climatic specificities on a regional and national scale. Finally, these studies have the potential to foster sustainable development at different geographical levels.
Subject(s)
Decision Trees , Environmental Monitoring , Groundwater , Groundwater/chemistry , Algeria , Water Pollution/analysis , Water Pollutants, Chemical/analysis , Risk AssessmentABSTRACT
INTRODUCTION: Chronic kidney disease (CKD) stage 5 is a common pathology, the increase in its incidence and prevalence has been noted worldwide. In Algeria, few studies have been done on the epidemiology of chronic kidney disease, the real extent of its incidence in southern Algeria remains unknown. AIM: To determine the incidence in 2017 of chronic kidney disease stage 5 treated by renal replacement in southeastern Algeria. METHOD: During our multicenter, prospective longitudinal regional study, from January 1, 2017 to December 31, 2017, all resident incident cases of CKD stage 5 treated in the region by renal replacement were recruited. RESULTS: The crude incidence of stage 5 CKD treated in 2017 in southeastern Algeria was 75 pmh. The age-standardized incidence rate was 100 pmh, with a male predominance, a M/F sex ratio of 1.59. The average age of incident cases was 48.50 ± 19.12 years. The incidence varies by age group and by wilaya. Diabetes (26.7%) and hypertensive nephropathy (22.6%) represent almost half of the cases and primary glomerulonephritis represents 5.9%. CONCLUSION: CKD stage 5 treated, due to its high incidence in Algeria, with large geographical variations, represents a major public health challenge. It mainly affects young people. Diabetes and high blood pressure represent the two main causes, encouraging prevention efforts to be focused on hypertensives and diabetics in high-risk wilayas.
Subject(s)
Renal Insufficiency, Chronic , Humans , Algeria/epidemiology , Male , Female , Incidence , Middle Aged , Adult , Renal Insufficiency, Chronic/epidemiology , Aged , Prospective Studies , Young Adult , Adolescent , Longitudinal Studies , Child , Aged, 80 and over , Child, Preschool , Renal Replacement Therapy/statistics & numerical data , Hypertension/epidemiologyABSTRACT
This study aims to assess the amount of organic carbon stored in soils, as it is an intention of knowing the sustainable soil management, by using two common methods for determining soil organic matter (SOM), namely oxidation with acidified wet dichromate (Walkley-Black method-WB) and loss on ignition (LOI). The study was carried with soil samples collected from a depth of 0 to 30 cm in the Saharan arid region of Ghardaïa (Algeria), with different land uses: agricultural, forest and pastoral. The results obtained from the LOI and WB methods were subjected to statistical analysis, and the relations between both methods were tested to investigate their relationship. The mean percentage of SOM values were 1.86, 2.42, 1.54 by using LOI, but, lower values of 0.34, 0.33, 0.36 were determined by using WB method, for agricultural, forest and pastoral soils respectively. A weak linear relationship between the two analytical procedures was obtained (R2 of 0.19 and 0.13 for agricultural and forest soils), while a medium relationship (R2 = 0.65) was found for pastoral soils when using linear adjustment. However, the opposite behaviour was found when we use the logarithmic adjustment. The study outcomes indicated discrepancies in the measurements of SOM values between the two methods, been higher those estimated with LOI. Finally, in order to identify the best methodology to measure soil organic matter in arid soils, more research is required in these extreme arid regions as they are a gap in world soil organic matter maps.
Subject(s)
Agriculture , Carbon , Soil , Algeria , Soil/chemistry , Carbon/analysis , Forests , Environmental Monitoring/methods , Carbon Sequestration , Desert ClimateABSTRACT
The contents of water-soluble major's ions (MSA, Cl-, NO3-, SO42-, Na+, NH4+, K+, Mg2+, and Ca2+) in the PM10 particle fraction were investigated thanks to detailed measurements of the main chemical constituents of PM10 in remote coastal areas in Bou-Ismail; in the South-West of the Mediterranean Sea (Algeria), during a 2-year period; from July 2011 to August 2013, under the framework of the ChArMEx project (Chemistry-Aerosol Mediterranean Experiment, http://charmex.lsce.ipsl.fr ). The total water-soluble ion concentrations in PM10 at the Bou-Ismail measurement station varied from 3.3 µg/m3 (July 2011) to 49.6 µg/m3 (March 2012). The annual mean mass concentrations of ions in the PM10 particulate fraction were Cl- > Na+ > SO42- > Mg2+ > NO3- > Ca2+ > K+ > NH4+ > Oxalate. The change in potassium nss-K + concentrations in PM10 over the course of a year reveals that biomass burning (BB) has an effect on three separate seasons: the beginning of winter (February and March), the end of summer (August), and the autumn (September and October). The origin periods of biomass burning BB identified employing the mapping of hotspots and fires during periods of August and September 2011, 2012, and 2013 underlined the important fires in the surrounding areas of the Mediterranean Sea (Sardinia Islands from Italy, Corsica from France).
Subject(s)
Air Pollutants , Environmental Monitoring , Ions , Particulate Matter , Algeria , Particulate Matter/analysis , Air Pollutants/analysis , Mediterranean Sea , SeasonsABSTRACT
The groundwater salinization process complexity and the lack of data on its controlling factors are the main challenges for accurate predictions and mapping of aquifer salinity. For this purpose, effective machine learning (ML) methodologies are employed for effective modeling and mapping of groundwater salinity (GWS) in the Mio-Pliocene aquifer in the Sidi Okba region, Algeria, based on limited dataset of electrical conductivity (EC) measurements and readily available digital elevation model (DEM) derivatives. The dataset was randomly split into training (70%) and testing (30%) sets, and three wrapper selection methods, recursive feature elimination (RFE), forward feature selection (FFS), and backward feature selection (BFS) are applied to train the data. The resulting combinations are used as inputs for five ML models, namely random forest (RF), hybrid neuro-fuzzy inference system (HyFIS), K-nearest neighbors (KNN), cubist regression model (CRM), and support vector machine (SVM). The best-performing model is identified and applied to predict and map GWS across the entire study area. It is highlighted that the applied methods yield input variation combinations as critical factors that are often overlocked by many researchers, which substantially impacts the models' accuracy. Among different alternatives the RF model emerged as the most effective for predicting and mapping GWS in the study area, which led to the high performance in both the training (RMSE = 1.016, R = 0.854, and MAE = 0.759) and testing (RMSE = 1.069, R = 0.831, and MAE = 0.921) phases. The generated digital map highlighted the alarming situation regarding excessive GWS levels in the study area, particularly in zones of low elevations and far from the Foum Elgherza dam and Elbiraz wadi. Overall, this study represents a significant advancement over previous approaches, offering enhanced predictive performance for GWS with the minimum number of input variables.
Subject(s)
Groundwater , Machine Learning , Salinity , Algeria , Groundwater/chemistry , Environmental Monitoring/methods , Support Vector Machine , Models, TheoreticalABSTRACT
Purpose: In this study, we retrospectively reviewed the use of flow cytometry (FCM) in the diagnosis of inborn errors of immunity (IEIs) at a single center in Algeria. Sharing insights into our practical experience, we present FCM based diagnostic approaches adapted to different clinical scenarios. Methods: Between May 2017 and February 2024, pediatric and adult patients presenting with clinical features suggestive of immunodeficiency were subjected to FCM evaluation, including lymphocyte subset analysis, detection of specific surface or intracellular proteins, and functional analysis of immune cells. Results: Over a nearly seven-year period, our laboratory diagnosed a total of 670 patients (372 (55.5%) males and 298 (44.5%) females), distributed into 70 different IEIs belonging to 9 different categories of the International Union of Immunological Societies classification. FCM was used to diagnose and categorize IEI in 514 patients (76.7%). It provided direct diagnostic insights for IEIs such as severe combined immunodeficiency, Omenn syndrome, MHC class II deficiency, familial hemophagocytic lymphohistiocytosis, and CD55 deficiency. For certain IEIs, including hyper-IgE syndrome, STAT1-gain of function, autoimmune lymphoproliferative syndrome, and activated PI3K delta syndrome, FCM offered suggestive evidence, necessitating subsequent genetic testing for confirmation. Protein expression and functional assays played a crucial role in establishing definitive diagnoses for various disorders. To setup such diagnostic assays at high and reproducible quality, high level of expertise is required; in house reference values need to be determined and the parallel testing of healthy controls is highly recommended. Conclusion: Flow cytometry has emerged as a highly valuable and cost-effective tool for diagnosing and studying most IEIs, particularly in low-income countries where access to genetic testing can be limited. FCM analysis could provide direct diagnostic insights for most common IEIs, offer clues to the underlying genetic defects, and/or aid in narrowing the list of putative genes to be analyzed.
Subject(s)
Flow Cytometry , Humans , Flow Cytometry/methods , Male , Female , Algeria , Child , Child, Preschool , Infant , Adolescent , Adult , Retrospective Studies , Immunophenotyping , Young Adult , Infant, Newborn , Immunologic Deficiency Syndromes/diagnosis , Immunologic Deficiency Syndromes/immunology , Immunologic Deficiency Syndromes/geneticsABSTRACT
BACKGROUND: Staphylococcus aureus can colonize and infect a variety of animal species. In dairy herds, it is one of the leading causes of mastitis cases. The objective of this study was to characterize the S. aureus isolates recovered from nasal swabs of 249 healthy cows and 21 breeders of 21 dairy farms located in two provinces of Algeria (Tizi Ouzou and Bouira). METHODS: The detection of enterotoxin genes was investigated by multiplex PCRs. Resistance of recovered isolates to 8 antimicrobial agents was determined by disc-diffusion method. The slime production and biofilm formation of S. aureus isolates were assessed using congo-red agar (CRA) and microtiter-plate assay. Molecular characterization of selected isolates was carried out by spa-typing and Multi-Locus-Sequence-Typing (MLST). RESULTS: S. aureus was detected in 30/249 (12%) and 6/13 (28.6%) of nasal swabs in cows and breeders, respectively, and a total of 72 isolates were recovered from positive samples (59 isolates from cows and 13 from breeders). Twenty-six of these isolates (36.1%) harbored genes encoding for staphylococcal enterotoxins, including 17/59 (28.8%) isolates from cows and 9/13 (69.2%) from breeders. Moreover, 49.1% and 92.3% of isolates from cows and breeders, respectively, showed penicillin resistance. All isolates were considered as methicillin-susceptible (MSSA). Forty-five (76.3%) of the isolates from cows were slime producers and 52 (88.1%) of them had the ability to form biofilm in microtiter plates. Evidence of a possible zoonotic transmission was observed in two farms, since S. aureus isolates recovered in these farms from cows and breeders belonged to the same clonal lineage (CC15-ST15-t084 or CC30-ST34-t2228). CONCLUSIONS: Although healthy cows in this study did not harbor methicillin-resistant S. aureus isolates, the nares of healthy cows could be a reservoir of enterotoxigenic and biofilm producing isolates which could have implications in human and animal health.
Subject(s)
Biofilms , Enterotoxins , Staphylococcal Infections , Staphylococcus aureus , Animals , Cattle , Staphylococcus aureus/genetics , Staphylococcus aureus/drug effects , Staphylococcus aureus/isolation & purification , Algeria , Enterotoxins/genetics , Female , Staphylococcal Infections/veterinary , Staphylococcal Infections/microbiology , Staphylococcal Infections/epidemiology , Drug Resistance, Bacterial/genetics , Anti-Bacterial Agents/pharmacology , Carrier State/veterinary , Carrier State/microbiology , Dairying , Cattle Diseases/microbiologyABSTRACT
The main goal of this study was to assess the bioactive and polysaccharide compositions, along with the antioxidant and antibacterial potentials, of five seaweeds collected from the northeastern coast of Algeria. Through Fourier transform infrared spectroscopy analysis and X-ray fluorescence spectroscopy, the study investigated the elemental composition of these seaweeds and their chemical structure. In addition, this study compared and identified the biochemical makeup of the collected seaweed by using cutting-edge methods like tandem mass spectrometry and ultra-high-performance liquid chromatography, and it searched for new sources of nutritionally valuable compounds. According to the study's findings, Sargassum muticum contains the highest levels of extractable bioactive compounds, showing a phenolic compound content of 235.67 ± 1.13 µg GAE·mg-1 and a total sugar content of 46.43 ± 0.12% DW. Both S. muticum and Dictyota dichotoma have high concentrations of good polyphenols, such as vanillin and chrysin. Another characteristic that sets brown algae apart is their composition. It showed that Cladophora laetevirens has an extracted bioactive compound content of 12.07% and a high capacity to scavenge ABTS+ radicals with a value of 78.65 ± 0.96 µg·mL-1, indicating high antioxidant activity. In terms of antibacterial activity, S. muticum seaweed showed excellent growth inhibition. In conclusion, all five species of seaweed under investigation exhibited unique strengths, highlighting the variety of advantageous characteristics of these seaweeds, especially S. muticum.