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Chemical Composition, Characterization and Factors Affecting Household Dust (<20 µm) in Greater Cairo, Egypt

Open Journal of Air Pollution 2015年第4期4卷 184-197页

作者： Salwa K. Hassan ahmed A. El-Abssawy Mamdouh I. Khoder Air Pollution Department National Research Centre Giza Egypt Environmental Sciences Department Faculty of Meteorology Environment and Arid Land Agriculture King Abdulaziz University Jeddah Saudi Arabia Center of Excellence in Environmental Studies King Abdulaziz University Jeddah Saudi Arabia

Adverse health and environmental effects of household dust are derived from their chemical composition and properties. In this study, household, stairs and entryway dust (<20 μm) samples from homes located in urban, residential and residential near to industrial area in Greater Cairo during summer 2013 were collected to study their chemical composition, characterization and factors affecting them. Results indicate that the levels of measured anions and cations were higher in the household compared to stairs and entryway dust. The highest concentration of ?, , Cl-?,?, Na+, K+, Ca2+ and Mg2+ in the household and entryway dust was found in urban area. was abundant in household, entryway and stairs dust followed by Cl- and . Its average concentrations were 21.38, 14.57 and 15.83 mg/g, respectively. The household/entryway (I/O) concentration ratios of measured ion components indicate that these species might derive from indoor sources, although outdoor sources could be present as well. pH values of household, stairs and entryway dust ranged from 6.43 to 8.53, indicating that these dusts brought a large amount of crustal species, and might alleviate the tendency of acidification. The relationships between the concentrations of acidic components ( and ) and basic components (, Ca2+ and Mg2+) in household, stairs and entryway dust confirm that the acidity of dust is neutralized. Ca2+ and in household and stairs dust and Ca2+ and Mg2+ in entryway dust are the most dominant neutralization substances.

关键词： Household Stairs and Entryway Dust Chemical Composition and Characterization Greater Cairo Egypt

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The Distribution and Accretion of Some Heavy Metals in Makkah Wells

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Journal of Water Resource and Protection 2014年第11期6卷 998-1010页

作者： Nezar H. M. Khdary ahmed E. H. Gassim King Abdulaziz City for Science and Technology Riyadh KSA Makkah Toxicology Center Research Unit Makkah KSA

The aim of this study is to determine the types of heavy metals frequently present in Makkah wells and the possible environmental causes of their distribution and accumulation. Makkah lies in a mountain range dominated by different types of rocks from the Precambrian and Lower Paleozoic eras, as well as subordinate sedimentary rocks and basaltic lava flow from the Tertiary and Quaternary periods. Natural contaminants in Makkah wells water can be attributed to the unique location. Many epidemiological studies have identified associations between the ingestion of wells water contaminated with heavy metals and increased risk of some illnesses. This study presents exclusive information on the levels and distribution of 9 heavy metals—arsenic, barium, cadmium, chromium, cobalt, copper, lead, mercury, and selenium—in the wells water in various rural and urban areas of Makkah city. These naturally occurring elements are considered significant markers of water purity. More than 160 wells were involved in this three-year investigation. Water samples were collected during different seasons in order to assess any changes in the distribution and concentration of these heavy metals throughout the year. The collected water samples were filtered and digested before analysis using inductively coupled plasma mass spectrometry (ICP/MS). We found the following sequence of concentrations of heavy metals in the studied wells: Ba > Se >Cr > As > Co > Cu> Hg > Pb > Cd. Arsenic, barium, chromium, and selenium were the most abundant contaminants in the wells studied. The concentrations of the other heavy metals ranged from non-detectable to 3 μg/L. Although low, these values are also reported in comparisons with the local and international strict values and standards which govern the maximum contaminant levels permitted for long-term daily consumption.

关键词： Makkah Wells Water Contamination Heavy Metals Rural and Urban Areas ICP/MS

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Experimental Investigation of Effects of Electric Operating Parameters on Pulsed Corona Discharges in Humid Air at Atmospheric Pressure

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Journal of Analytical Sciences, Methods and Instrumentation 2018年第4期8卷 49-64页

作者： Hasna Guedah Alyen Abahazem Nofel Merbahi Mohamed Yousfi Karim Saber ahmed Ihlal Laboratory Materials and Renewable Energies Physics Department Ibn Zohr University Agadir Morocco CRMEF-SM Inezgane Morocco LAPLACE UMR 5213-CNRS Paul Sabatier University Toulouse France

The present work is devoted to electrical and optical study of a point-plane atmospheric pressure corona discharge reactor in humid air powered by pulsed high voltage supply. The corona current and the injected energy are analyzed as a function of several parameters such as applied voltage and humidity rate. Then, investigations based on emission spectroscopy analysis were used in UV range (from 200 nm to about 400 nm). The main observed excited species were the second positive (SPS), the first negative (FNS) systems and OH(A-X) rotational bands. The latter band was used to simulate the rotational temperature (Tr), whereas the N2+ (FNS) band was used to determine the vibrational temperature (Tv). The electron temperature (Te ) is determined from the ratio of line intensities of the spectral bands of both N2+ FNS at 391.4 nm and N2SPS at 394.4 nm. The rotational, vibrational and electronic temperatures are analyzed as a function of above parameters (applied voltage, frequency and hygrometry rate) near the anodic tip. As well we study the axial variation of electronic temperature for a fixed applied voltage at 6.4 kV, frequency at 10 kHz and 100% of humidity. It is found that the rotational, vibrational and electronic temperatures increased with increasing applied voltage, frequency and humidity rate. The increase of rate hygrometry for an inter-electrode distance fixed at 10 mm causes an increase in both the amplitude of the corona current discharge and the energy injected in corona discharge. This is indicative of more intense reactive plasma while increasing hygrometry rate.

关键词： Corona Discharge Atmospheric Pressure Optical Emission Spectroscopy Pulsed High Voltage Humidity

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Efficacy of Some Antibiotics in Curing Resistant <i>Escherichia coli</i>Infection

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Journal of Biosciences and Medicines 2015年第7期3卷 31-53页

作者： Tarek El-Banna ahmed Abd El-Aziz Nageh EL-Mahdy Yasmine Samy Microbiology Department Faculty of Pharmacy Tanta University Tanta Egypt Pharmacology Department Faculty of Pharmacy Tanta University Tanta Egypt Pharmaceutical Sciences Faculty of Pharmacy Tanta University Tanta Egypt

There is growing interest in re-evaluation of older antibiotics with the wide spread of pathogen resistance, especially gram negative bacteria, which impair treatment of some infections. In contrast various studies have reported that some antibiotics have efficacy in clearing resistant bacterial infections. On account of that it was interesting to evaluate the efficacy of erythromycin, chloramphenicol and/or tenoxicam in curing and/or relieving wound infection of highly resistant Escherichia coli and investigate the possible mechanisms beyond their antibacterial activity. This was achieved through evaluating highly resistant E. coli strains in vitro using agar dilution and in vivo rat models of E. coli infected wound and acute inflammation by carrageenin, where possible mechanisms were evaluated through measuring immunological mediators and histopathological examination. This study revealed that in vivo, erythromycin alone or in combination with tenoxicam significantly improved the healing of infected skin wounds with E. coli irresspective of resistancy in vitro. In addition to the improvement of immunological mediators involved in inflammatory reaction, oxidative stress and in cytokines expression as response to the bacterial infection in vivo. On the other hand chloramphenicol neither alone nor in combination with tenoxicam, achieved any significant effect. Tenoxicam didn’t show antimicrobial activity alone nor in combination with tested antibiotics in vitro, but it has shown synergestic activity in combination with tested antibiotics in vivo. Thus we concluded that immunomodulatory activity of erythromycin through anti-inflammatory and antioxidant effects was the possible mechanisms by which this antibiotic had healed infection with resistant E. coli in vivo, despite its resistancy to this antibiotic in vitro.

关键词： Efficacy Antibiotics Resistant E. coli Infection

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Fabrication and Characterization on Physico-Mechanical and Structural Properties of Sawdust Reinforced Acrylonitrile Butadiene Styrene (ABS) Composites

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Materials Sciences and Applications 2020年第9期11卷 644-658页

作者： Budrun Neher Nabila Tasnim Nova Rakib Hossain M. A. Gafur Farid ahmed Department of Physics Jahangirnagar University Dhaka Bangladesh Department of Physics Bangabandhu Sheikh Mujibur Rahman Science & Technology University Gopalganj Bangladesh PP and PDC Bangladesh Council of Scientific and Industrial Research Dhaka Bangladesh

The sawdust reinforced Acrylonitrile Butadiene Styrene (ABS) composites were prepared by using hot press molding machine for five different wt% (0%, 5%, 10%, 15% and 20%) at 180°C temperature and 50 KN load. Sawdust was collected from local saw mill of Savar, Dhaka, Bangladesh and ABS polymer was collected from local market of Dhaka, Bangladesh. In this study, different properties of composites like physical (bulk density and water absorption), mechanical (tensile properties and hardness) and structural (Fourier Transform Infrared Spectroscopy) properties were studied. The bulk density of composites was not altered consistently and it gave greater value for 5% and 20% composites. The water absorption enhanced for all composites with the accumulation of fiber content and soaking time. The reduction of tensile strength and Leeb’s rebound hardness of the composites were observed with the increase of the fiber content in all compositions. Maximum (%) of elongation was found for 5% composite, and then it gradually decreased;however, elastic modulus increased with the increased of fiber content in composites. Fourier Transform Infrared (FTIR) spectroscopy study was done for structural characterization. It was found that there was a new bond (C≡C) stretching formed for 20% composite;moreover, C-H rocking for 0% composite was broken for all other composites after the addition of sawdust in ABS polymer matrix.

关键词： Sawdust-ABS Composite Hot Press Molding Machine Tensile Strength Leeb’s Rebound Hardness FTIR Spectroscopy

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Clinical Isolates of Staphylococcus aureus Show Variation in β-Lactamase Production and Are More Susceptible to Antibiotics Conjugated with β-Lactamase Inhibitors

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Open Journal of Medical Microbiology 2016年第4期6卷 143-149页

作者： Uzal Umar Umar ahmed Faruk Damoroem M. Tanko Mohammed B. Yerima Department for Biological Sciences Abubakar Tafawa Balewa University Bauchi Nigeria Department of Microbiology Federal University Dutse Dutse Nigeria

β-Lactam antibiotics are a cornerstone in the treatment of bacterial infections on account of its high therapeutic index and selective toxicity—they act by inhibiting the biosynthesis of peptidoglycan, a key component in bacterial cell wall. Ninety (90) clinical specimens obtained from the microbiology unit Specialist Hospital Bauchi were screened for S. aureus, positive isolates were examined for β-Lactamase expression by using two Penicillin G concentrations (5000 IU/ml and 25,000 IU/ml) in acidometric agar technique with phenol red as indicator, and the susceptibility pattern of the isolates to β-Lactam antibiotics was also determined. S. aureus prevalence of 31% (28/90) was obtained, of which 96% (27/28) of strains were β-Lactamase positive in the standard test, while 63% (17/27) were able to hydrolyze penicillin G concentration of 25,000 IU/ml (5X the concentration in the standard test), and a strain was found to be β-Lactamase negative. The resistance to five β-Lactams, ampicillin, cephalexin, amoxicillin, cloxacillin and flucloxaillin, were 100%, 96%, 89%, 74% and 56% respectively. When ampicillin and amoxicillin were conjugated to β-Lactamase inhibitors sulbactam and clavulanic acid respectively the resistance to ampicillin decreased to 21% and to amoxicillin to 15%. The antibiotic susceptibility profile revealed β-Lactamase elaboration to be the major mechanism of resistance to the β-Lactams. β-Lactam utilization as therapeutic option would thus require the search for sensitive irreversible β-Lactamase inhibitors for the β-Lactamase enzymes or agents to block the release of β-Lactamase by strains.

关键词： β-Lactamase Peptidoglycan Transpeptidation Haemolysis Resistance Antibiotics

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HER2-Specific Vaccines for HER2-Positive Breast Cancer Immunotherapy

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World Journal of Vaccines 2015年第2期5卷 106-128页

作者： Maxwell Omabe Shahid ahmed Amer Sami Yufeng Xie Min Tao Jim Xiang Cancer Research Cluster Saskatchewan Cancer Agency Saskatoon Canada Department of Oncology University of Saskatchewan Saskatoon Canada Department of Oncology The first Affiliated Hospital Soo-Chow University Suzhou China

Anti-human epidermal growth factor receptor-2 (HER2) immunization can be elicited by vaccination with DNA encoding the extra- or intra-cellular domain (ECD or ICD) of HER2, naked or encap-sulated in viral vectors. HER2-peptides derived from ECD or ICD of HER2, and HER2-pulsed dendritic cells (DCs) or engineered DCs expressing HER2, respectively. We performed a computer- based literature search which includes but is not limited to the following keywords: breast cancer, immunotherapy, HER2-peptide vaccine, HER2-DNA vaccine, HER-DC vaccine, HER2 vaccine, and HER2/neu, in PubMed, Medline, EMBO and Google Scholar;data from recently reported clinical trials were also included. Drawing upon this synthesis of literature, this work summarizes the de-velopment and current trend in experimental and clinical investigations in HER2-positive breast cancer using HER2-specific vaccine and immunotherapy, focusing especially on: (i) DNA-;(ii) peptide-;and (iii) DC-based vaccines. It addresses interventions that have been applied to overcome immunotolerance thereby to improve treatment outcomes. These include blocking the inhibitory cytotoxic T lymphocyte-associated protein-4 (CTLA-4), which is expressed at high levels by regulatory T (Treg) cells, or complete Treg depletion to improve T-cell activation. Moreover, modulatory interventions can provide further improvement in the efficacy of HER2-specific vaccine. The interventions include the use of immunogenic adjuvants such as cytokines interleukin-12 (IL-12), tumor necrosis factor (TNF)-α and granulocyte-macrophage colony-stimulating factor (GM-CSF), the use of Toll-like receptor (TLR) ligands and tetanus toxin’s universal epitopes such as the CD4+ help T (Th)-epitope P30, and the use of either chimeric or heterogenous xenogeneic HER2. Combining active HER2-vaccination with adoptive trastuzumab antibody immunotherapy is likely to increase the effectiveness of each approach alone. The development of effective HER2-vaccines for breast

关键词： HER2 Breast Cancer DNA Peptide Dendritic Cell Vaccine

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GSTM1,GSTT1,GSTP1 and CYP1A1 genetic polymorphisms and susceptibility to esophageal cancer in a French population:Different pattern of squamous cell carcinoma and adenocarcinoma

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World Journal of Gastroenterology 2004年第23期10卷 3389-3393页

作者： ahmed Abbas Karine Delvinquière Mathilde Lechevrel Pierre Lebailly Pascal Gauduchon Guy Launoy Fran ois Sichel GRECAN-EA1772 UFR des Sciences Pharmaceutiques Université de Caen Basse-Normandie et Centre Francois BaclesseAvenue du Général Harris14076 Caen cedex 05France GRECAN-EA1772 Université de Caen Basse-Normandie et Registre des Tumeurs Digestives du Calvados UFR de MédecineAvenue de la C te de Nacre14032 Caen cedexFrance

AIM:To evaluate the association between CYP1A1 and GSTs genetic polymorphisms and susceptibility to esophageal squamous cell carcinoma(SCC)and esophageal adenocarcinoma(ADC)in a high risk area of northwest of France. METHODS:A case-control study was conducted to investigate the genetic polymorphisms of these enzymes (CYPIAI*2C and GSTP1 exon 7 Val alleles,GSTMI*2/*2 and GSTTl *2/*2 null genotypes).A total of 79 esophageal cancer cases and 130 controls were recruited. RESULTS:GSTMI*2/*2 and CYPIAI*IA/*2C genotype frequencies were higher among squamous cell carcinomas at a level dose to statistical significance(OR =1.83,95% CI 0.88-3.83,P=0.11;OR=3.03,95% CI 0.93-9.90,P=0.07, respectively).For GSTP1 polymorphism,no difference was found between controls and cases,whatever their histological *** frequency of GSTT1 deletion was observed in ADC group compared to controls with a statistically significant difference(OR=13.31,95% CI 1.66-106.92,P<0.01). CONCLUSION:In SCC,our results are consistent with the strong association of this kind of tumour with tobacco *** ADC,our results suggest 3 distinct hypotheses: (1)activation of exogenous procarcinogens,such as small halogenated compounds by GSTT1;(2)contribution of GSTT1 to the inflammatory response of esophageal mucosa,which is known to be a strong risk factor for ADC, possibly through leukotriene synthesis;(3)higher sensitivity to the inflammatory process associated with intracellular depletion of glutathione.

关键词： Acyltransferases Adenocarcinoma Adult Aged Aged, 80 and over Carcinoma, Squamous Cell Case-Control Studies Cytochrome P-450 CYP1A1 Esophageal Neoplasms Female France Genetic Predisposition to Disease Genotype Glutathione Transferase Humans Male Middle Aged Polymorphism, Genetic Research Support, Non-U.S. Gov't Risk Factors

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Knowledge Attitude and Practice about Water-Pipe Smoking among Saudi Population

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Journal of Biosciences and Medicines 2020年第3期8卷 58-72页

作者： Reema Fahad Abdulrahman Alnumair Amal Hussain Mohammed Ali Hussam ahmed Mohammed Alghamdi Department of Medical Laboratories College of Applied Medical Sciences Qassim University Qassim Kingdom of Saudi Arabia

Water pipe smoking has been practiced extensively for about 400 years. Water pipe smoking is common in the Saudi Arabia. Water-pipe smoking exposes smokers to high levels of tobacco and toxins. An observational and cross-sectional survey carried among 1170 participants to determine the knowledge, attitude, and practice about water-pipe smoking among Saudi population. Data was collected and obtained by the online questionnaire that has been created in Google form and then published in different social media platforms over a period from September 2019 to November 2019. The data were entered in Excel and analyzed in EpiInfo7 statistical software to get descriptive statistics. Results: About 70% were females and 30% male, 43% of them are university students with 83% in the age group of the 18 - 25 high participants. Low knowledge of Carbon monoxide poisoning effects = 78%, While 54% of the participants showed low knowledge about infectious disease transmitted by water-pipe. The Knowledge about water pipe contents and carbon monoxide poisoning was low. Further efforts will be necessary to increase the level of awareness among participants in Saudi Arabia regarding water pipe contents and carbon monoxide poisoning.

关键词： Knowledge Attitude Practice Water-Pipe Smoking Saudi

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Evaluating Discharge Capacity of Major Chara’s of Sylhet City Using GIS

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Journal of Water Resource and Protection 2018年第2期10卷 167-181页

作者： Gulam Md. Munna Jahir Bin Alam Jobayer ahmed Abdullah Al Mamun Department of Civil and Environmental Engineering Shahjalal University of Science and Technology (SUST) Kumargaon Sylhet-3114 Bangladesh

Heavy rainfall is one of the most frequent and widespread severe weather hazards that affect Sylhet city. In Sylhet, nine natural channels locally called “chara” are mainly responsible for the drainage of heavy rainfall to the Surma River. The present condition of this natural drainage is not feasible due to the unplanned land development and manipulation by people. So water logging is a common scenario of Sylhet city. Many parts of Sylhet city are experiencing the severe inundation problem due to heavy rainfall. Time series analysis of rainfall data (1974-2015) is important for knowing and predicting of rainfall variation. Mann-Kendall analysis showed no trend for monthly and yearly rainfall data. The rainfall intensity of Sylhet is higher than other districts of Bangladesh. In this study, IDF (Intensity Duration Frequency) curve has been developed that is commonly used in engineering planning and design. By using IDF curve, ArcGIS software, DEM map, and normal discharge, maximum discharge for a different point of Mongoli chara and Bolramer chara has been calculated (for 25 years return period). Discharge through Mongoli chara and Bolramer chara has been represented in ArcMap using ordinary kriging. To keep the catchment of those chara free from inundation and water logging problem, this calculated discharge needed to be managed.

关键词： ArcGIS Canal Chi-Square Gamble Distribution IDF Curve Mann-Kendall Rainfall

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