Optimizing Eco-Friendly Degradation of Polyvinyl Chloride (PVC) Plastic Using Environmental Strains of Malassezia Species and Aspergillus fumigatus.

Worldwide, huge amounts of plastics are being introduced into the ecosystem, causing environmental pollution. Generally, plastic biodegradation in the ecosystem takes hundreds of years. Hence, the isolation of plastic-biodegrading microorganisms and finding optimum conditions for their action is crucial. The aim of the current study is to isolate plastic-biodegrading fungi and explore optimum conditions for their action. Soil samples were gathered from landfill sites; 18 isolates were able to grow on SDA. Only 10 isolates were able to the degrade polyvinyl chloride (PVC) polymer. Four isolates displayed promising depolymerase activity. Molecular identification revealed that three isolates belong to genus Aspergillus, and one isolate was Malassezia sp. Three isolates showed superior PVC-biodegrading activity (Aspergillus-2, Aspergillus-3 and Malassezia) using weight reduction analysis and SEM. Two Aspergillus strains and Malassezia showed optimum growth at 40 °C, while the last strain grew better at 30 °C. Two Aspergillus isolates grew better at pH 8-9, and the other two isolates grow better at pH 4. Maximal depolymerase activity was monitored at 50 °C, and at slightly acidic pH in most isolates, FeCl3 significantly enhanced depolymerase activity in two Aspergillus isolates. In conclusion, the isolated fungi have promising potential to degrade PVC and can contribute to the reduction of environmental pollution in eco-friendly way.

Human Parvovirus B19 Infection in Rheumatoid Arthritis Patients: Screening and Clinical Significance.

Rheumatoid arthritis (RA) is a common chronic inflammatory disease, affecting about 1% of the general population. Conflicting data are available regarding the etiologic association of human parvovirus B19 (B19) infection with RA. This study aimed to determine the prevalence of B19 infection in patients with RA compared to healthy controls and to assess its possible association with disease activity or severity. The study included 40 RA patients and 40 age and sex matched apparently healthy controls. Detection of B19 DNA by nested PCR and the detection of anti-B19 IgM and IgG by ELISA) were performed for patients and controls. It was found that B19 infection is more prevalent in patients with RA than healthy controls as the frequency of detection of B19 DNA and anti-B19 IgG was significantly higher in RA patients than healthy controls (P=0.003 and P=0.04, respectively) but not IgM. It was concluded that B19 infection may have a role in the etiopathogenesis of RA but not involved in disease activity or severity.

Prevention of Bacterial Biofilm Formation on Soft Contact Lenses Using Natural Compounds.

PURPOSE: In eye care field, contact lenses (CL) have a great impact on improving vision, but their use can be limited by ocular infection. CL- associated infections can be reduced by good attention to CL storage case practice. CL-care solutions should be able to control microbial growth on CL. The aim of the study was to evaluate and compare the efficacy of CL-care solutions (found in Egyptian market) with some natural compounds in removal and inhibition of bacterial biofilm formed on soft CL. Clinical isolates were recovered from patients having conjunctivitis from Benha University Hospital and identified microbiologically. Quantification of biofilm was done using microtiter plate assay. Three multipurpose CL-care solutions were examined for their ability to remove and inhibit biofilm. Also four natural extracts having antibacterial activity and are safe on eye were tested for their anti-biofilm activity. RESULTS: The major bacterial isolates from eye infections were Pseudomonas aeruginosa (36%) and Staphylococcus spp. (37.8%). Only 33.3% of isolates showed ability to produce weak to moderate biofilm. The tested multi-purpose CL-care solutions showed moderate ability to remove preformed biofilm. Among the tested natural compounds, Calendula officinalis and Buddleja salviifolia extracts showed an excellent efficacy in inhibition of biofilm and also removal of preformed biofilm. CONCLUSION: This study demonstrated that isolates from infected eye and CL-cases showed weak to moderate biofilm formation. Calendula officinalis and Buddleja salviifolia extracts showed excellent effect on inhibition and removal of biofilm, these extracts could be added into CL-care solutions which could markedly reduce eye-infections during CL-wear.

Surface Expression and Genetic Variants of Toll-like Receptor 2 in Pulmonary Tuberculosis Patients.

Innate immunity plays an important role in the host defense against Mycobacterium tuberculosis (M. tuberculosis). Toll-like receptor-2 (TLR2) is the main receptor and one of central components in initiation of innate immunity against M. tuberculosis. The study aimed to evaluate TLR2 surface expression on peripheral blood monocytes and study its association with variants in TLR2 597T/C single nucleotide polymorphisms (SNPs) in patients with pulmonary tuberculosis. Fifty pulmonary tuberculosis patients and 50 healthy controls were investigated for TLR2 expression on CD14+ monocytes by flow cytometry and TLR2 597T/C genotyping by Tetra primer amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR). A significant increase (P < 0.001) in TLR 2 expression was detected in tuberculosis patients compared to controls. TLR2 597 TC and CC genotypes were higher in pulmonary tuberculosis patients (OR =2.79, 95% CI =1.02-7.95 and OR =4.26, 95% CI =0.40-214.00) respectively. Genotype TT was associated with reduced risk of being a case of pulmonary tuberculosis. There was no association of TLR2 surface expression on monocytes in pulmonary tuberculosis patients with different TLR2 597T/C genotypes. It is concluded that elevated expression of TLR2 on CD14+ monocytes in pulmonary tuberculosis patients confirms the role of TLR2 in host defense against M. tuberculosis. 597T/C polymorphism of TLR 2 gene may be a risk factor for susceptibility to pulmonary tuberculosis in a sample Egyptian population.

Impact of Helicobacter pylori Eradication on Absolute Telomere Length in Gastric Mucosa

Background and study aim: This study proposed to assess the relation between absolute telomere lengths (TLs) in gastric mucosa and Helicobacter pylori (H. pylori) infection and study the impact of (H. pylori) eradication therapy on TLs. Patients and Methods: This study was conducted on (42) subjects divided into two groups, group I: included (17) H. pylori negative cases served as control group, group II: included (25) H. pylori positive patients. Absolute TLs was measured in base pairs (bp) in gastric mucosa and analyzed by real time polymerase chain reaction (RT-PCR) in all groups and reevaluated in H. pylori positive patients 4 weeks after eradication therapy. Results: Prior to eradication therapy, there was highly significant shortening (P<0.001) in TLs (bp) in gastric mucosa of H. pylori positive patients compared to H. pylori negative controls. While there was highly significant elongation was observed after H. pylori eradication therapy in H. pylori positive patients (P < 0.001). There was significant negative correlation between TLs and ages of patients (P<0.001) while there was no significant relation between TLs and sex (P= 0.5) before and after eradication therapy. Conclusion: H. pylori positive patients had significantly shorter TLs than H. pylori negative controls. TLs were increased after H. pylori eradication therapy in H. pylori positive cases. This finding may indicate the importance of H. pylori eradication to avoid the development of gastric cancer by its effect on TLs