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Loose sands (siliceous, silty, and calcareous classes) are extensively found near arid areas in Egypt. Furthermore, many geotechnical structures, like water channels and roads, may be constructed on weak or loose sand soils. The geotechnical behavior of loose sands is usually connected with different interdependent problems, such as high permeability, low shear strength, low bearing capacity, high seepage, and low stability. This work characterized the effect of stabilization of the siliceous, silty, and calcareous sandy soils via biocementation process using Sporosarcina pasteurii bacteria as a potential eco, commercial, and engineering solution. This was carried out using bacteria, fixation, and cementation solutions (BFC) at different times number additions. The results indicated that the addition times of solution have a remarkable effect on the physical and mechanical properties of sandy soils. The results also proved that the precipitation of calcite by the bacterial activity led to cohesion of soil grains, and this increased the resistance of soils to deterioration. In addition, the high content of the precipitated calcium carbonate enhanced the shear strength and the unconfined compressive strength and decreased the soil permeability. S. pasteurii bacteria can be used successfully and commercially in the biocementation process for siliceous sand, silty sand, and calcareous sandy soils in Egypt using the recommended conditions and mixes.

Objectives To assess the in vitro activity of ceftazidime/avibactam against a recent, 2015–18, collection of clinical isolates of Gram-negative bacilli from Middle Eastern and African countries with a focus on isolates from ICUs and with MDR and difficult-to-treat resistance (DTR) phenotypes. Methods Antimicrobial susceptibility testing of 4608 isolates of Enterobacterales (997 isolates from ICU patients) and 1358 isolates of Pseudomonas aeruginosa (374 isolates from ICU patients) was performed by CLSI broth microdilution methodology in a central laboratory. MICs were interpreted using both CLSI (2020) and EUCAST (2020) MIC breakpoints. Results Most isolates of Enterobacterales (Middle East: ICU, 99.1% susceptible, non-ICU, 99.1%; Africa: ICU, 96.9% susceptible, non-ICU, 98.3%) and P. aeruginosa (Middle East: ICU, 93.4%, non-ICU, 92.1%; Africa: ICU, 89.8%; non-ICU, 94.1%) were susceptible to ceftazidime/avibactam. Applying CLSI and EUCAST breakpoints, MDR rates were similar for Enterobacterales (27.8%–36.0% of isolates) and P. aeruginosa (25.0%–36.4%) while DTR rates were lower for Enterobacterales (1.6%–1.8%) than for P. aeruginosa (5.2%–7.4%). Percentage susceptible rates for ceftazidime/avibactam for MDR Enterobacterales were 96.8%–97.5% (Middle East) and 92.5%–94.3% (Africa) while rates for P. aeruginosa were 70.1%–80.0% (Middle East) and 69.5%–78.2% (Africa). 60.5%–65.8% (Middle East) and 38.9%–52.2% (Africa) of isolates of Enterobacterales with DTR phenotypes were ceftazidime/avibactam susceptible as were 29.2%–31.1% (Middle East) and 28.2%–35.8% (Africa) of DTR P. aeruginosa. Conclusions Overall, the isolates of Enterobacterales and P. aeruginosa tested from Middle Eastern and African countries were highly susceptible to ceftazidime/avibactam. Most MDR and many DTR isolates of Enterobacterales and P. aeruginosa were susceptible to ceftazidime/avibactam.

This study aims to evaluate source rock formations (Kareem and Rudeis) through quantitative and qualitative analysis of pyrolysis data from 44 ditch samples from three wells (Elkhaligue-1, Kareem-1...

Biological process in soil improvement which is known as biocementation soil improvement technique has shown greater potential in geotechnical engineering applications such as slope stabilization and increasing sand strength. Egypt has more than 50,000 km irrigation and drainage channels. The main type of soil constituting a soil layer of most of the canal embankment in the Nile delta is the loosely soil. It is exposed to slope stability problems. This work focused on studying stabilization of the loosely soils via biocementation process and it was applied on sands to improve their mechanical properties by different treatment methods using bacteria named Sporosarcina pasteurii. These methods are injection with and without fixations, and mixing method. The main results showed that the injection methods of the bacteria with fixation solution in the treated soil was effective than the injection without fixation solution at the same conditions. Also, it is suggested to add solutions gradually to prevent precipitation of calcite on the surface of sand. Furthermore, using a growth media without sterilization has no negative effect on the bacterial activity. Meanwhile, using a growth media without centrifuge processes and bacteria incubation at 12 h instead of 24 h were more economy. This method leads to improvement of soil of large scale in site with low effort and relatively at short time when using the mixing method. The studied physicomechanical properties were significantly increased in biocemented sand for all methods used and they were superior for the injection with fixation method. The XRD results and SEM images indicated the deposition of calcium carbonates in biocemented sand. It is concluded that Sporosarcina pasteurii can be used commercially for sand biocementation process.

Objectives To report antimicrobial susceptibility testing surveillance data for ceftaroline and comparative agents from the AWARE global surveillance programme for bacterial pathogens causing skin and soft tissue infections (SSTIs) and lower respiratory infections (RTIs) in Middle East and African countries from 2015 to 2018. Methods Pathogens were identified by MALDI-TOF/MS. Antimicrobial susceptibility testing was performed using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method. MICs were interpreted by both CLSI (M100, 2020) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) (v 10.0, 2020) breakpoints. Results All MSSA (n = 1125) and 93.9% of MRSA (n = 1235) were susceptible to ceftaroline (MIC ≤ 1 μg/mL, CLSI and EUCAST). The maximum ceftaroline MIC observed for MRSA was 2 μg/mL; no ceftaroline-resistant MRSA were identified among SSTI (CLSI and EUCAST) and RTI (CLSI) isolates. All isolates of β-haemolytic Streptococcus (n = 324), and penicillin-susceptible (PSSP) and -intermediate Streptococcus pneumoniae (PISP; n = 369) were susceptible to ceftaroline. Rates of susceptibility to ceftaroline for penicillin-resistant S. pneumoniae (penicillin MIC ≥ 2 μg/mL; n = 175), and β-lactamase-negative (BLNHI; n = 224) and β-lactamase-positive Haemophilus influenzae (n = 49) were 99.4%, 98.7%, and 98.0% (CLSI) and 92.6%, 98.2%, and 83.7% (EUCAST), respectively. Rates of susceptibility to ceftaroline for ESBL-negative Escherichia coli (n = 442), Klebsiella pneumoniae (n = 381), and Klebsiella oxytoca (n = 103) were 92.1%, 93.2%, and 96.1%, respectively. Conclusion Ceftaroline-resistant isolates of MRSA causing SSTIs were not identified in Middle East and African countries in 2015–2018 using recently revised CLSI (in 2019) or EUCAST (in 2018) breakpoint criteria. Common bacterial pathogens causing SSTIs (Staphylococcus aureus, β-haemolytic Streptococcus) and lower RTIs (PSSP, PISP, BLNHI) demonstrated no resistance or low levels of resistance (0–1.8%) to ceftaroline.

Little information is available on the functional activity of leukocytes after arthroplasty or the expansion of populations with immune suppressive properties during the acute post-operative period. Synovial fluid and matched pre- and post-surgical blood samples were collected from total hip and knee arthroplasty patients (THA and TKA, respectively) to examine the impact of surgery on peripheral blood leukocyte frequency, bactericidal activity, and inflammatory mediator expression. For spinal surgeries, inflammatory mediator production by peripheral blood mononuclear cells (PBMCs) pre- and post-surgery was examined. An expansion of immune suppressive granulocytic myeloid-derived suppressor cells (G-MDSCs) was observed following arthroplasty, which correlated with significantly increased serum interleukin-10 (IL-10) levels. Analysis of synovial fluid from THA and TKAs revealed reduced granulocyte colony-stimulating factor (G-CSF) and soluble CD40 ligand (sCD40L) and increased interleukin-6 (IL-6), monocyte chemoattractant protein 2 (CCL2) and Fms-like tyrosine kinase 3 ligand (Flt-3L) compared to pre- and post-surgical serum. For the spinal surgery cohort, stimulation of PBMCs isolated post-surgery with bacterial antigens produced significantly less pro-inflammatory (IL-1&alpha, IL-1&beta, interleukin-1 receptor antagonist (IL-1RA), IL-12p40, growth-related oncogene-&alpha, /GRO-&alpha, (CXCL1) and 6Ckine (CCL21)) and more anti-inflammatory/tissue repair mediators (IL-10, G-CSF and granulocyte-macrophage colony-stimulating factor (GM-CSF)) compared to PBMCs recovered before surgery. The observed bias towards systemic anti-inflammatory changes without concomitant increases in pro-inflammatory responses may influence susceptibility to infection following orthopaedic surgery in the context of underlying co-morbidities or risk factors.

SThe pyrolysis and vitrinite reflectance estimations for fifteen shale rock tests and additionally, geochemical burial history, and gas chromatography – mass spectrometry parameters were ta...

BackgroundStaphylococcus aureus surgical-site infections (SSIs) are a major cause of poor health outcomes, including mortality, across surgical specialties. Despite current advances as a result of preventive interventions, the disease burden of S. aureus SSI remains high, and increasing antibiotic resistance continues to be a concern. Prophylactic S. aureus vaccines may represent an opportunity to prevent SSI.MethodsA review of SSI pathophysiology was undertaken in the context of evaluating new approaches to developing a prophylactic vaccine to prevent S. aureus SSI.ResultsA prophylactic vaccine ideally would provide protective immunity at the time of the surgical incision to prevent initiation and progression of infection. Although the pathogenicity of S. aureus is attributed to many virulence factors, previous attempts to develop S. aureus vaccines targeted only a single virulence mechanism. The field has now moved towards multiple-antigen vaccine strategies, and promising results have been observed in early-phase clinical studies that supported the recent initiation of an efficacy trial to prevent SSI.ConclusionThere is an unmet medical need for novel S. aureus SSI prevention measures. Advances in understanding of S. aureus SSI pathophysiology could lead to the development of effective and safe prophylactic multiple-antigen vaccines to prevent S. aureus SSI.

The organic matters of Rudeis and Kareem formation from Ras Budran oilfield in the central Gulf of Suez, Egypt, were investigated throughout the study of biomarkers and infrared spectrometric analyses. The results showed that Pr/Ph, Pr/n-C17, and Ph/n-C18 ratios indicated marine source organic matters deposited under reduced condition with a less effect of biodegradation and mature stage of occurrence. The gammacerane index indicated a low-salinity environment of deposition for the initial organic matters existed in the analyzed samples. Steranes distributions show high percentage of C28 steranes and C29 steranes compared with C27 steranes, and low-concentration C27 diasteranes show generally low ratios indicating anoxic carbonate source rocks. The diasteranes/steranes showed generally low ratios indicating most marine carbonate sources. The tricyclic terpane reflects mature organic matters and originated from marine organic sources.

Organic matters from the KK 85-1and HH 83-1wells in the Central Gulf of Suez were analyzed by two well-proven organic geochemical methods: Rock-Eval pyrolysis and gas chromatography–mass spectrometry (GC–MS) analyses. These techniques were used to obtain independent parameters of organic matter composition, thermal maturity, and environment of deposition. The study reveals a close concordance between Rock-Eval pyrolysis data and biomarkers parameters such as steranes and triterpanes. Rock-Eval pyrolysis in conjunction with GC–MS analyses shows that the organic matters contain two types of kerogen (Type-II/III and Type III), which lie dominantly prior to the peak stage of the conventional oil window (end of diagensis–beginning of catagensis). The case study shows that these methods are suitable for a proper assessment of the petroleum potential of source rocks and the rapid geochemical characterization of sedimentary organic matter.

Staphylococcus aureus capsular polysaccharides (CP) are important virulence factors under evaluation as vaccine antigens. Clinical S. aureus isolates have the biosynthetic capability to express either CP5 or CP8 and an understanding of the relationship between CP genotype/phenotype and S. aureus epidemiology is valuable. Using whole genome sequencing, the clonal relatedness and CP genotype were evaluated for disease-associated S. aureus isolates selected from the Tigecycline Evaluation and Surveillance Trial (T.E.S.T) to represent different geographic regions in the United States (US) during 2004 and 2009–10. Thirteen prominent clonal complexes (CC) were identified, with CC5, 8, 30 and 45 representing >80% of disease isolates. CC5 and CC8 isolates were CP type 5 and, CC30 and CC45 isolates were CP type 8. Representative isolates from prevalent CC were susceptible to in vitro opsonophagocytic killing elicited by anti-CP antibodies, demonstrating that susceptibility to opsonic killing is not linked to the genetic lineage. However, as not all S. aureus isolates may express CP, isolates representing the diversity of disease isolates were assessed for CP production. While approximately 35% of isolates (primarily CC8) did not express CP in vitro, CP expression could be clearly demonstrated in vivo for 77% of a subset of these isolates (n = 20) despite the presence of mutations within the capsule operon. CP expression in vivo was also confirmed indirectly by measuring an increase in CP specific antibodies in mice infected with CP5 or CP8 isolates. Detection of antigen expression in vivo in relevant disease states is important to support the inclusion of these antigens in vaccines. Our findings confirm the validity of CP as vaccine targets and the potential of CP-based vaccines to contribute to S. aureus disease prevention. Publisher PDF

The aim of this paper is to define the source rock potential of hydrocarbon generation through the determination of: (1) the quantity of organic matter, (2) present day kerogen types, (3) thermal maturity and (4) source organic matter input and depositional conditions of the source rock from Kareem, Rudeis and Matulla Formations, and Nubia Sandstone in 2 wells namely GH 376-1 and GH 404-1 throughout pyrolysis, vitrinite reflectance measurements and gas chromatographic analyses. The results suggest that Kareem and Rudeis source rocks have poor to good generating potential to generate both gas and oil at optimum maturity, Matulla source has a very good while Nubia has poor generating potential to generate both oil and gas at optimum maturity. The organic matter of Kareem, Rudeis and Nubia source rocks was deposited in marine environment under reducing conditions, while Matulla Formation deposited in transition environments and tends to be of terrestrial rather than marine sources.

Oil–oil and oil–source rock correlations are used in this study in order to achieve their relationship, depositional environments and diagenetic processes in the source rocks. Three oil samples and source rock hydrocarbon extracts were analyzed using relative geochemical analyses, and gas chromatography–mass spectrometry are used for this purpose. The results revealed that the extracts of the Alam El Bueib and Khatatba formations are derived from mixed organic sources in which terrestrial dominates marine sources, and deposited in transitional environments under less anoxic conditions. The extracts of Bahariya formation are derived from mixed marine inputs with a limited terrestrial contribution. The Alam El Bueib oil shows more contribution of terrestrial than marine sources. Also, a genetic close relation between them supported the indigenous mixed source of Alam El Bueib oil which related to different sources including the Khatatba, Alam El Bueib and Bahariya formations. Accordingly, the Alam El Bueib formation can be considered as an important source for petroleum generation in the Northern Western Desert.

Fifteen rock samples were subjected to comprehensive organic geochemical studies aiming to evaluate potential source rocks as well as to predict the time of petroleum generation and expulsion of Kharita, Alam El Bueib, and Khataba Fms. in some wells in Meleiha area. The study revealed the Kharita Fm. is immature and has fair potential to produce gas. The organic matter is derived from terrestrial origin. Alam El Bueib Fm. is mature with fair to good capability of producing mixed oil and gas. The organic matter is originated mainly from mixed organic sources. Khatatba Fm. is mature and has good potentiality for generating oil. The organic matter is derived mainly from marine origin. The geothermal profile revealed that Kharita Fm. reached only the early stage of hydrocarbon generation and did not enter the oil widow till the present time. Alam El Bueib Fm. entered the oil window during Late Eocene time. Khatatba Fm. entered the oil window during Late Cretaceous. Consequently, Khatatba Fm. in Meleih...

Twenty-two ditch samples were collected from GH-376-1 well, representing the Miocene and Paleozeoic rocks of GH-376 oilfield in the South Gulf of Suez. These were subjected to TOC, S2, Tmax, HI, and OI, and gas chromatography analyses. The results showed that Kareem Formation source rocks are immature and have fair to good potential of type III/II of kerogen for generating mixed gas and oil, but mainly gas. The organic matters are derived mainly from marine contribution from algae and bacteria deposited under reducing environments. Rudies Formation is immature and has poor to fair potential of type II/III kerogen for generating gas. The organic matter is derived mainly from marine and terrestrial sources deposited under oxidizing-reducing environments. Sudr Formation has poor to fair potential of type III kerogen to generate gas. The organic matter has been derived mainly from terrestrial sources deposited under oxidizing conditions. Matulla Formation is immature and has good to very good potentia...

Staphylococcus aureus (S. aureus) is a challenging bacterial pathogen which can cause a range of diseases, from mild skin infections, to more serious and invasive disease including deep or organ space surgical site infections, life-threatening bacteremia, and sepsis. S. aureus rapidly develops resistance to antibiotic treatments. Despite current infection control measures, the burden of disease remains high. The most advanced vaccine in clinical development is a 4 antigen S. aureus vaccine (SA4Ag) candidate that is being evaluated in a phase 2b/3 efficacy study in patients undergoing elective spinal fusion surgery (STaphylococcus aureus suRgical Inpatient Vaccine Efficacy [STRIVE]). SA4Ag has been shown in early phase clinical trials to be generally safe and well tolerated, and to induce high levels of bactericidal antibodies in healthy adults. In this review we discuss the design of SA4Ag, as well as the proposed clinical development plan supporting licensure of SA4Ag for the prevention of invasive disease caused by S. aureus in elective orthopedic surgical populations. We also explore the rationale for the generalizability of the results of the STRIVE efficacy study (patients undergoing elective open posterior multilevel instrumented spinal fusion surgery) to a broad elective orthopedic surgery population due to the common pathophysiology of invasive S. aureus disease and commonalties of patient and procedural risk factors for developing postoperative S. aureus surgical site infections.

While select eudesmane sesquiterpenes exhibit anti-neoplastic activity, tumor-inhibition for costic-acids has not been established. Here biological activity of 3-oxo-γ-costic acid (1), previously isolated from Chiliadenus montanus, as well as new sesquiterpenes (2–5) and the known derivative, 3-oxoeudesma-1,4,11(13)-trien-7-1061αH-l2-oic acid (6), all produced from 1 by the fungus Athelia rolfsii, are reported. Structures were elucidated using MS and NMR spectroscopy with activity-screening utilizing human colon- and lung-tumor lines, Caco-2 and A549 respectively. Compound 1 exhibited anti-proliferative activity against Caco-2 (IC50 39 µM) and 2 was active against A549 (IC50 74 µM) suggesting therapeutic potential for the original substrate and a bio-transformed product.

S. R. H. and J. P. were supported by Wellcome Trust grant 098051. This work was funded by Pfizer Vaccine Research and Development. Staphylococcus aureus USA300 represents the dominant community-associated methicillin-resistant S. aureus lineage in the USA, where it is a major cause of skin and soft tissue infections. Previous comparative genomic studies have described the population structure and evolution of USA300 based on geographically restricted isolate collections. Here, we investigated the USA300 population by sequencing genomes of a geographically distributed panel of 191 clinical S. aureus isolates belonging to clonal complex 8 (CC8), derived from the Tigecycline Evaluation and Surveillance Trial program. Isolates were collected at 12 healthcare centres across nine USA states in 2004, 2009 or 2010. Reconstruction of evolutionary relationships revealed that CC8 was dominated by USA300 isolates (154/191, 81 %), which were heterogeneous and demonstrated limited phylogeographic clustering. Analysis of the USA300 core genomes revealed an increase in median pairwise SNP distance from 62 to 98 between 2004 and 2010, with a stable pattern of above average dN/dS ratios. The phylogeny of the USA300 population indicated that early diversification events led to the formation of nested clades, which arose through cumulative acquisition of predominantly non-synonymous SNPs in various coding sequences. The accessory genome of USA300 was largely homogenous and consisted of elements previously associated with this lineage. We observed an emergence of SCCmec negative and ACME negative USA300 isolates amongst more recent samples, and an increase in the prevalence of ϕSa5 prophage. Together, the analysed S. aureus USA300 collection revealed an evolving pan-genome through increased core genome heterogeneity and temporal variation in the frequency of certain accessory elements. Publisher PDF

Staphylococcus aureus is both a commensal organism and also an important opportunistic human pathogen, causing a variety of community and hospital-associated pathologies, such as bacteremia-sepsis, endocarditis, pneumonia, osteomyelitis, arthritis and skin diseases. The resurgence of S. aureus during the last decade in many settings has been facilitated not only by bacterial antibiotic resistance mechanisms but also by the emergence of new S. aureus clonal types with increased expression of virulence factors and the capacity to neutralize the host immune response. Prevention of the spread of S. aureus infection relies on the use of contact precautions and adequate procedures for infection control that so far have not been fully effective. Prevention using a prophylactic vaccine would complement these processes, having the potential to bring additional, significant progress toward decreasing invasive disease due to S. aureus.

In continuation of our chemical investigation on some medicinal plants of the genus Achillea, chromatographic investigation of the methylene chloride/methanol (1:1) extract of the air-dried aerial part of Achillea biebersteinii Afan. (family Asteraceae) afforded a new natural monoterpene (2), in addition to two known sesquiterpenes (3 and 4). Compound 1 was isolated as light needle crystals. Structures were established on the basis of MS and NMR spectroscopic (1H, 13C, 1H-1H correlation spectroscopy, heteronuclear multiple-quantum coherence and heteronuclear multiple-bond correlation) data and in case of compound 1 were confirmed by X-ray analysis. All isolated compounds were examined for their anti-inflammatory activity to inhibit lipopolysaccharide-induced NO production in RAW264.7 macrophage cells. Compounds 3 and 4 produced a promising anti-inflammatory effect (76% and 80% inhibition, respectively). However, compounds 1 and 2 produced moderate inhibition of NO release recording a 41% and 36% inhibition of NO production, respectively.

Bacteria isolated from marine sponges, including the Silicibacter-Ruegeria (SR) subgroup of the Roseobacter clade, produce N-acylhomoserine lactone (AHL) quorum sensing signal molecules. This study is the first detailed analysis of AHL quorum sensing in sponge-associated bacteria, specifically Ruegeria sp. KLH11, from the sponge Mycale laxissima. Two pairs of luxR and luxI homologues and one solo luxI homologue were identified and designated ssaRI, ssbRI and sscI (sponge-associated symbiont locus A, B and C, luxR or luxI homologue). SsaI produced predominantly long-chain 3-oxo-AHLs and both SsbI and SscI specified 3-OH-AHLs. Addition of exogenous AHLs to KLH11 increased the expression of ssaI but not ssaR, ssbI or ssbR, and genetic analyses revealed a complex interconnected arrangement between SsaRI and SsbRI systems. Interestingly, flagellar motility was abolished in the ssaI and ssaR mutants, with the flagellar biosynthesis genes under strict SsaRI control, and active motility only at high culture density. Conversely, ssaI and ssaR mutants formed more robust biofilms than wild-type KLH11. AHLs and the ssaI transcript were detected in M. laxissima extracts, suggesting that AHL signalling contributes to the decision between motility and sessility and that it may also facilitate acclimation to different environments that include the sponge host.

Summary The aim of the present study was to evaluate the association of Glycine102Serine molecular variant of luteinising hormone (LH) β-subunit gene with infertility in Egyptian males and to assess the impact of oxidative stress in association with Glycine102Serine molecular variant on male infertility. Fifty men with idiopathic oligozoospermia were enrolled in the study. The control group consisted of 39 men with normal semen parameters and proven fertility. Variable oxidative status markers were evaluated. Glycine102Serine variant was investigated using restriction fragment length polymorphism-polymerase chain reaction. The study concluded that Glycine102Serine variant of LH β-subunit gene is relatively common among infertile Egyptian males and might be implicated in some Egyptian infertility cases. In addition, the association of this variant, in some cases, with disturbed oxidative status (decreased seminal plasma antioxidants’ level and increased sperm lipid peroxidation) probably have a significant role in accentuation of infertility in those particular cases.

Artemisia, one of the larger genera in the family Asteraceae and the largest genus in the tribe Anthemideae, comprises from 200 to more than 500 taxa at the specific or subspecific level. Many Artemisia species have a high economic value in several fields, as food plants and as antihelminthic and antimalaria in medicine. Artemisia herba-alba was known for its therapeutic and medicinal properties, it was used in both traditional and modern medicine. Several papers have been published on the chemical composition of specimens of A. herba-alba. The aim of this work is to review all available scientific literature published on A. herba-alba. The focus will be on the chemical constitutions which have been identified from this species, in addition to all of the reported biological activites of this species have been included as well as the pharmacology and toxicology

Red Sea sponges offer potential as sources of novel drugs and bioactive compounds. Sponges harbor diverse and abundant prokaryotic communities. The diversity of Egyptian sponge-associated bacterial communities has not yet been explored. Our study is the first culture-based and culture-independent investigation of the total bacterial assemblages associated with two Red Sea Demosponges, Hyrtios erectus and Amphimedon sp. Denaturing gradient gel electrophoresis fingerprint-based analysis revealed statistically different banding patterns of the bacterial communities of the studied sponges with H. erectus having the greater diversity. 16S rRNA clone libraries of both sponges revealed diverse and complex bacterial assemblages represented by ten phyla for H. erectus and five phyla for Amphimedon sp. The bacterial community associated with H. erectus was dominated by Deltaproteobacteria. Clones affiliated with Gammaproteobacteria were the major component of the clone library of Amphimedon sp. About a third of the 16S rRNA gene sequences in these communities were derived from bacteria that are novel at least at the species level. Although the overall bacterial communities were significantly different, some bacterial groups, including members of Alphaproteobacteria, Gammaproteobacteria, Acidobacteria, and Actinobacteria, were found in both sponge species. The culture-based component of this study targeted Actinobacteria and resulted in the isolation of 35 sponge-associated microbes. The current study lays the groundwork for future studies of the role of these diverse microbes in the ecology, evolution, and development of marine sponges. In addition, our work provides an excellent resource of several candidate bacteria for production of novel pharmaceutically important compounds.

Marine sponges contain complex assemblages of bacterial symbionts, the roles of which remain largely unknown. We identified diverse bacterial nifH genes within sponges and found that nifH genes are expressed in sponges. This is the first demonstration of the expression of any protein-coding bacterial gene within a sponge. Two sponges Ircinia strobilina and Mycale laxissima were collected from Key Largo, Florida and had delta(15)N values of c. 0-1 per thousand and 3-4 per thousand respectively. The potential for nitrogen fixation by symbionts was assessed by amplification of nifH genes. Diverse nifH genes affiliated with Proteobacteria and Cyanobacteria were detected, and expression of nifH genes affiliated with those from cyanobacteria was detected. The nifH genes from surrounding seawater were similar to those of Trichodesmium and clearly different from the cyanobacterial nifH genes detected in the two sponges. This study advances understanding of the role of bacterial symbionts in sponges and suggests that provision of fixed nitrogen is a means whereby symbionts benefit sponges in nutrient-limited reef environments. Nitrogen fixation by sponge symbionts is possibly an important source of new nitrogen to the reef environment that heretofore has been neglected and warrants further investigation.

Marine sponges in the genus Ircinia are known to be good sources of secondary metabolites with biological activities. A major obstacle in the development of sponge-derived metabolites is the difficulty in ensuring an economic, sustainable supply of the metabolites. A promising strategy is the ex situ culture of sponges in closed or semiclosed aquaculture systems. In this study, the marine sponge Ircinia strobilina (order Dictyoceratida: family Irciniidae) was collected from the wild and maintained for a year in a recirculating aquaculture system. Microbiological and molecular community analyses were performed on freshly collected sponges and sponges maintained in aquaculture for 3 months and 9 months. Chemical analyses were performed on wild collected sponges and individuals maintained in aquaculture for 3 months and 1 year. Denaturing gradient gel electrophoresis was used to assess the complexity of and to monitor changes in the microbial communities associated with I. strobilina . Culture-based and molecular techniques showed an increase in the Bacteroidetes and Alpha - and Gammaproteobacteria components of the bacterial community in aquaculture. Populations affiliated with Beta - and Deltaproteobacteria , Clostridia , and Planctomycetes emerged in sponges maintained in aquaculture. The diversity of bacterial communities increased upon transfer into aquaculture.

The changes in bacterial communities associated with the marine sponge Mycale laxissima on transfer to aquaculture were studied using culture-based and molecular techniques. M. laxissima was maintained alive in flowthrough and closed recirculating aquaculture systems for 2 years and 1 year, respectively. The bacterial communities associated with wild and aquacultured sponges, as well as the surrounding water, were assessed using 16S rRNA gene clone library analysis and denaturing gradient gel electrophoresis (DGGE). Bacterial richness and diversity were measured using DOTUR computer software, and clone libraries were compared using S-LIBSHUFF. DGGE analysis revealed that the diversity of the bacterial community of M. laxissima increased when sponges were maintained in aquaculture and that bacterial communities associated with wild and aquacultured M. laxissima were markedly different than those of the corresponding surrounding water. Clone libraries of bacterial 16S rRNA from sponges confirmed that the bacterial communities changed during aquaculture. These communities were significantly different than those of seawater and aquarium water. The diversity of bacterial communities associated with M. laxissima increased significantly in aquaculture. Our work shows that it is important to monitor changes in bacterial communities when examining the feasibility of growing sponges in aquaculture systems because these communities may change. This could have implications for the health of sponges or for the production of bioactive compounds by sponges in cases where these compounds are produced by symbiotic bacteria rather than by the sponges themselves.

Actinobacteria exclusively within the sub-class Acidimicrobidae were shown by 16S rDNA community analysis to be major components of the bacterial community associated with two sponge species in the genus Xestospongia. Four groups of Actinobacteria were identified in Xestospongia spp., with three of these four groups being found in both Xestospongia muta from Key Largo, Florida and Xestospongia testudinaria from Manado, Indonesia. This suggests that these groups are true symbionts in these sponges and may play a common role in both the Pacific and Atlantic sponge species. The fourth group was found only in X. testudinaria and was a novel assemblage distantly related to any previously sequenced actinobacterial clones. The only actinobacteria that were obtained in initial culturing attempts were Gordonia, Micrococcus and Brachybacterium spp., none of which were represented in the clone libraries. The closest cultured actinobacteria to all the Acidimicrobidae clones from Xestospongia spp. are 'Microthrix parvicella' and Acidimicrobium spp. Xestospongia spp. can now be targeted as source material from which to culture novel Acidimicrobidae to investigate their potential as producers of bioactive compounds. Isolation of sponge-associated Acidimicrobidae will also make it possible to elucidate their role as sponge symbionts.

Operations planning and scheduling (OPS) problems in advanced manufacturing systems, such as flexible manufacturing systems, are composed of a set of interrelated problems, such as part-type batching, machine grouping, tool loading, routing, part input sequencing and on-line scheduling. In this paper, an integrated, simulation-based approach to the OPS problems is discussed. A detailed simulation model is developed using FORTRAN and SLAM II which integrates loading, part inputting, routeing and dispatching issues of the OPS. An experimental frame is developed which provides statistical analysis of the simulation output by developing an experimental design. Statistical analyses concerning a number of system parameters (e.g. loading strategies and scheduling rules) are performed on a set of performance measures.

Phytochemical investigation of the methylenechloride/methanol extract of the aerial parts of Stachys aegyptiaca afforded a new neoclerodane-type diterpene with a new side chain 1, in addition to two known diterpenes 2 and 3 and a known flavonoid glycoside 4. The structures of the compounds were determined by comprehensive NMR studies including DEPT, COSY, NOESY, HMQC, HMBC and HR-MS.

Aerobic ammonia-oxidizing bacteria (AAOB) are known to have an important function in the marine nitrogen cycle. Anaerobic ammonium oxidation (anammox) carried out by some members of Planctomycetales is also an important process in marine ecosystems. Ammonia-monooxygenase gene (amoA) fragments were amplified to investigate the potential for nitrification and the diversity of the AAOB in two marine sponges Ircinia strobilina and Mycale laxissima. All of the AmoA sequences obtained from the two sponges clustered with the AmoA sequences of the Betaproteobacteria Nitrosospira spp. To investigate the anaerobic ammonia-oxidizing bacteria (AnAOB) in sponges, 16S rRNA gene fragments of Planctomycetales and anammox bacteria were also amplified with specific primers, and clone libraries were constructed. The Planctomycetales diversity detected in the two sponges was different. The Planctomycetales community in M. laxissima was affiliated with Pirellula, Planctomyces and anammox bacteria, while all of the I. strobilina Planctomycetales clones were solely affiliated with the candidate phylum 'Poribacteria'. Interestingly, sequences related to anammox genera were recovered only from M. laxissima. This is the first report of anammox bacteria in marine sponges. It is intriguing to find AAOB and AnAOB in M. laxissima, but the nature of their interaction with the sponge host and with each other remains unclear. This work further supports the potential of sponge-associated microorganisms for nitrification and sheds light on anammox as a new aspect of the nitrogen cycle in marine sponges.

Summary Marine sponges are hosts to diverse and dense bacterial communities and thus provide a potential environment for quorum sensing. Quorum sensing, a key factor in cell–cell communication and bacterial colonization of higher animals, might be involved in the symbiotic interactions between bacteria and their sponge hosts. Given that marine Proteobacteria are known to produce N-acyl homoserine lactone (AHL) signal molecules, we tested the production of AHLs by Alpha- and Gammaproteobacteria isolated from marine sponges Mycale laxissima and Ircinia strobilina and the surrounding water column. We used three different AHL biodetection systems in diffusion assays: Chromobacterium violaceum, Agrobacterium tumefaciens and Sinorhizobium meliloti with optimal sensitivity to short-chain (C4–C6), moderate-chain (C8–C12) and long-chain (≥ C14) AHLs respectively. Thirteen of 23 isolates from M. laxissima and five of 25 isolates from I. strobilina were found to produce AHLs. Signals were detected from two of eight proteobacterial strains from the water column. Thin-layer chromatographic assays based on the A. tumefaciens reporter system were utilized to determine the AHL profiles of the positive isolates. The types and amounts of AHLs synthesized varied considerably among the strains. Small ribosomal rRNA gene sequencing revealed that the AHL-producing alphaproteobacterial isolates were mainly from the Silicibacter–Ruegeria subgroup of the Roseobacter clade. Two-dimensional gel electrophoresis (2DGE)-based proteomic analyses were congruent with phylogenetic relationships but provided higher resolution to differentiate these closely related AHL-producing strains.

Ageratum conyzoides L., is an annual herb with a long history of traditional medicinal uses in many countries in the world, especially in the tropical and subtropical regions. A wide range of chemical compounds including alkaloids, flavonoids, chromenes, benzofurans and terpenoids have been isolated from this species. Extracts and metabolites from this plant have been found to possess pharmacological and insecticidal activities. In continuation of our interest in the Egyptian medicinal plants, the reinvestigation of the methylenechloride extract of the air-dried aerial parts of Ageratum conyzoides afforded a new natural compound 1 , pyrrolone, 5-ethoxy-1H-pyrrol-2(5H)-one, together with a known flavonoid. The structures of the compounds were determined by comprehensive NMR studies, including DEPT, COSY, HMQC, HMBC, and MS.

Phytochemical studies of the aerial parts of Euphorbia rigida afforded three triterpenes: betulin (1), cycloart-23Z-ene-3, 25-diol (2) and cycloartan-3, 24, 25-triol (3), firstly isolated from this plant. The structures and relative stereochemistry were determined on the basis of extensive spectroscopic analyses, including 1D and 2D NMR experiments (1H NMR, 13C NMR, COSY, NOESY, HMQC and HMBC).

The present work discusses the fundamental structure of simulation models (components, relations, terms, etc…); their basic elements, the programming language, and model structure and requirements. The study aims to define the role of simulation in design of a dynamic system such as FMS. A simulation study is carried out to demonstrate the application of simulation models. The system to be examined is a planned PMColl. The major task was to evaluate design issues such as the effect of priority rules for job sequencing, the determination of the number of pallets limit, and better conveyor speed.

The present work aims to evaluate the organic geochemistry of the crude oils recovered from Ashrafi and GH oilfields within the Gulf of Suez to assess and investigate oil characterization, maturation, source depositional environments and oil families. The saturated hydrocarbons were determined by gas chromatography and gas chromatography/mass spectrometry. Pristane/phytane, isoprenoids/n-alkanes, CPI, homohopane, diasteranes, gammacerane index, C29 20S/20S+20R, C29/C30 hopane and Ts/Tm are determined. The results suggest that the studied crude oils belong to marine oil and are characterized by high level of maturation and sourced mainly from organic matters of marine origin with few terrestrial inputs.

The aim of this paper is to define the source rock potential of hydrocarbon generation through the determination of: (1) the quantity of organic matter, (2) present day kerogen types, (3) thermal maturity and (4) source organic matter input and depositional conditions of the source rock from Kareem, Rudeis and Matulla Formations, and Nubia Sandstone in 2 wells namely GH 376-1 and GH 404-1 throughout pyrolysis, vitrinite reflectance measurements and gas chromatographic analyses. The results suggest that Kareem and Rudeis source rocks have poor to good generating potential to generate both gas and oil at optimum maturity, Matulla source has a very good while Nubia has poor generating potential to generate both oil and gas at optimum maturity. The organic matter of Kareem, Rudeis and Nubia source rocks was deposited in marine environment under reducing conditions, while Matulla Formation deposited in transition environments and tends to be of terrestrial rather than marine sources.