Al Zawiya University

About: Al Zawiya University is a education organization based out in Az Zāwīyah, Libya. It is known for research contribution in the topics: Computer science & Chemistry. The organization has 96 authors who have published 136 publications receiving 1136 citations. The organization is also known as: al-Zawiya University & Al Zawiya University.

PAH-degrading rhizobacteria of Lepironia articulata for phytoremediation enhancement

Abstract: This study identified plant rhizobacteria that have the capability to degrade polycyclic aromatic hydrocarbons (PAHs) and assist the plant in enhancing the phytoremediation process of PAH-contaminated wastewater. Rhizobacteria were isolated from the rhizosphere zone of Lepironia articulata exposed to 1%, 2% and 3% diesel concentrations (VDiesel/VWater). Thirty colonies were isolated, and after morphological and biochemical tests, they were classified into 23 colonies. These colonies were screened with a 3% diesel concentration (VDiesel/VWater) and only nine rhizobacteria (coded as A, B, C, D, E, F, G, H and I) were able to tolerate and sustain this. The extensive biodegradation of PAHs was carried out on the nine isolated rhizobacteria (individually as a monoculture), and it was found that the three rhizobacteria identified as Pseudomonas toyotomiensis strain ND1 (E), Microbacterium resistens strain ND2 (G) and Bacillus pumilus train ND3 (I) were highly able to remove PAHs (>80 % removal). Further biodegradation studies on the 16 components of PAHs were conducted for mixed cultures (E + G + I, G + E, G + I and E + I), and a mixed culture of G + E was found to be the best group in degrading PAHs (89 % removal). The existence of rhizobacteria, either as a monoculture or mixed culture, assisted the degradation of PAHs, thus enhancing the removal of PAH from wastewater. This study revealed the promising potential of the newly identified PAH degraders as candidates in enhancing the phytoremediation efficiency of PAH.

Molecular diagnosis of Toxoplasma gondii infection in Libya.

Abstract: Toxoplasma gondii infections are prevalent in humans and animals throughout Libya. Current diagnosis is based on detection of Toxoplasma-specific IgM and IgG. In this study, we established and optimized a diagnostic PCR assay for molecular diagnosis of T. gondii in Libya. From January to December, 2010, 177 blood and serum samples were collected from suspected patients. This includes: 140 women who have had spontaneous abortions, 26 HIV-positive patients, nine patients with leukemia and lymphoma, and two infants with ocular infection. Samples were screened for anti-Toxoplasma IgG and IgM antibodies before DNA extraction. The surface antigen gene 2 (SAG2) was targeted in a semi-nested PCR to amplify a 999 bp and a 614 bp fragment in the first and the second run respectively. A total of 54/140 (38.5 %) women who have had spontaneous abortions, 23/26 (88 %) HIV patients, 6/9 (66.6 %) of the leukaemia and lymphoma patients, and one child with ocular infection were seropositive for anti-Toxoplasma IgG and/or IgM. Genomic DNA was extracted from 38 selected seropositive samples. The PCR was sensitive enough to detect DNA concentration of 12 ng/μL. PCR analysis was performed for 38 selected seropositive patients (16 women who have had spontaneous abortions, 15 positive HIV patients, six leukaemia patients and one child with ocular infection). Our designed primers were successfully amplified in 22/38 (57.9 %) samples; 5/12 (35.7 %) from serum and 17/26 (65.8 %) from whole blood samples. All PCR positive samples were IgG-positive except two samples which were IgM and IgG & IgM-positive serum samples respectively. The semi-nested PCR confirmed five more samples. These included two leukaemia and two HIV-positive whole blood samples and one serum sample from an aborted woman. The ability of PCR to diagnose active toxoplasmosis is needed in immunocompromised patients and congenital toxoplasmosis cases, especially when serological techniques fail. For the first time in Libya, we established and optimized semi-nested PCR of SAG2 gene. The developed PCR method was able to detect as little as 12 ng/μL of T. gondii DNA and was useful to diagnose the diseases in women who have had spontaneous abortions, HIV-positive patients, patients with leukemia and lymphoma, and infants with ocular infection.

Deletion of AMPKα1 attenuates the anticontractile effect of perivascular adipose tissue (PVAT) and reduces adiponectin release

Abstract: Background and Purpose Perivascular adipose tissue (PVAT) surrounds most blood vessels and secretes numerous active substances, including adiponectin, which produce a net anticontractile effect in healthy individuals. AMPK is a key mediator of cellular energy balance and may mediate the vascular effects of adiponectin. In this study, we investigated the role of AMPK within PVAT in mediating the anticontractile effect of PVAT. Experimental Approach Endothelium-denuded aortic rings from wild-type (WT; Sv129) and α1AMPK knockout (KO) mice were mounted on a wire myograph. Dose–response curves to the AMPK-independent vasodilator cromakalim were studied in vessels with and without PVAT, and effect of pre-incubation with conditioned media and adiponectin on relaxation was also studied. The effect of AMPKα1 KO on the secretory profile of PVAT was assessed by elisa. Key Results Thoracic aortic PVAT from KO mice was morphologically indistinct from that of WT and primarily composed of brown adipose tissue. PVAT augmented relaxation to cromakalim in WT but not KO aortic rings. Addition of WT PVAT augmented relaxation in KO aortic rings but KO PVAT had no effect in WT rings. PVAT from KO mice secreted significantly less adiponectin and addition of adiponectin to either KO or WT aortic rings without PVAT augmented relaxation to cromakalim. An adiponectin blocking peptide significantly attenuated relaxation in WT rings with PVAT but not in KO rings. Conclusions and Implications AMPKα1 has a critical role in maintaining the anticontractile actions of PVAT; an effect independent of the endothelium but likely mediated through altered adiponectin secretion or sensitivity. Linked Articles This article is part of a themed section on Molecular Mechanisms Regulating Perivascular Adipose Tissue – Potential Pharmacological Targets? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.20/issuetoc

AMP-activated protein kinase complexes containing the β2 regulatory subunit are up-regulated during and contribute to adipogenesis.

Abstract: AMP-activated protein kinase (AMPK) is a heterotrimer of α-catalytic and β- and γ-regulatory subunits that acts to regulate cellular and whole-body nutrient metabolism. The key role of AMPK in sensing energy status has led to significant interest in AMPK as a therapeutic target for dysfunctional metabolism in type 2 diabetes, insulin resistance and obesity. Despite the actions of AMPK in the liver and skeletal muscle being extensively studied, the role of AMPK in adipose tissue and adipocytes remains less well characterised. Small molecules that selectively influence AMPK heterotrimers containing specific AMPKβ subunit isoforms have been developed, including MT47-100, which selectively inhibits complexes containing AMPKβ2. AMPKβ1 and AMPKβ2 are the principal AMPKβ subunit isoforms in rodent liver and skeletal muscle, respectively, yet the contribution of specific AMPKβ isoforms to adipose tissue function, however, remains largely unknown. This study therefore sought to determine the contribution of AMPKβ subunit isoforms to adipocyte biology, focussing on adipogenesis. AMPKβ2 was the principal AMPKβ isoform in 3T3-L1 adipocytes, isolated rodent adipocytes and human subcutaneous adipose tissue, as assessed by the contribution to total cellular AMPK activity. Down-regulation of AMPKβ2 with siRNA inhibited lipid accumulation, cellular adiponectin levels and adiponectin secretion during 3T3-L1 adipogenesis, whereas down-regulation of AMPKβ1 had no effect. Incubation of 3T3-L1 cells with MT47-100 selectively inhibited AMPK complexes containing AMPKβ2 whilst simultaneously inhibiting cellular lipid accumulation as well as cellular levels and secretion of adiponectin. Taken together, these data indicate that increased expression of AMPKβ2 is an important feature of efficient adipogenesis.

Coarse-resolution Ecology of Etiological Agent, Vector, and Reservoirs of Zoonotic Cutaneous Leishmaniasis in Libya

Abstract: Cutaneous leishmaniasis ranks among the tropical diseases least known and most neglected in Libya. World Health Organization reports recognized associations of Phlebotomus papatasi, Psammomys obesus, and Meriones spp., with transmission of zoonotic cutaneous leishmaniasis (ZCL; caused by Leishmania major) across Libya. Here, we map risk of ZCL infection based on occurrence records of L. major, P. papatasi, and four potential animal reservoirs (Meriones libycus, Meriones shawi, Psammomys obesus, and Gerbillus gerbillus). Ecological niche models identified limited risk areas for ZCL across the northern coast of the country; most species associated with ZCL transmission were confined to this same region, but some had ranges extending to central Libya. All ENM predictions were significant based on partial ROC tests. As a further evaluation of L. major ENM predictions, we compared predictions with 98 additional independent records provided by the Libyan National Centre for Disease Control (NCDC); all of these records fell inside the belt predicted as suitable for ZCL. We tested ecological niche similarity among vector, parasite, and reservoir species and could not reject any null hypotheses of niche similarity. Finally, we tested among possible combinations of vector and reservoir that could predict all recent human ZCL cases reported by NCDC; only three combinations could anticipate the distribution of human cases across the country.