Engineering Tumor Cells with Tumor Necrosis Factor α (TNF-α) or CD40 Ligand (CD40L) Genes Induce Anti-tumor Immune Responses

International Journal of Peptide Research and Therapeutics - One of the main problems in tumor therapy is immunosuppressive microenvironment of the tumor. To overcome this, we assessed targeted...     

Kinetic modelling of organic matter removal in 80 horizontal flow reed beds for domestic sewage treatment

This paper reports a comparative study of four kinetic models that can be applied in the design of subsurface horizontal flow reed beds for wastewater treatment. The models were developed from different combinations of Monod kinetics, first-order kinetics, continuous stirred-tank reactor and plug flow patterns. Using three statistical parameters (coefficient of determination, relative root mean square error, and model efficiency), critical examinations were made on the accuracy of these models. For predicting organic matter removal, the combination of Monod kinetics with plug flow pattern gave the closest match between theoretical predictions and actual performances of 80 horizontal flow reed beds. In all four models, the coefficients of BOD removal were found to increase slightly with BOD loading. The ratios of BOD/COD had no correlation with the coefficients, indicating that in the horizontal flow reed beds the degradation of organic matter is insensitive to the nature of organics in the wastewater.     

Production of a novel glycerol-inducible lipase from thermophilic <Emphasis Type="Italic">Geobacillus stearothermophilus</Emphasis> strain-5

In a screening program for isolation of thermophilic lipase-producing bacteria, a number of thermophilic bacteria were isolated from desert soil from Baltim, Egypt. Among 55 isolates, a potent bacterial candidate (starin-5) was characterized and identified by biochemical and PCR techniques, based on 16S rRNA sequencing. Phylogenetic analysis revealed its closeness to geobacilli especially the thermophilic Geobacillus stearothermophilus with optimal growth and lipolytic enzyme activity at 60°C and pH 7.0. An inducible nature of lipolytic enzyme synthesis using glycerol and glucose was demonstrated. Approximately, 94–100% of the original activity was retained due to thermal stability of the crude enzyme after heat treatment for 15 min at 30–60°C. The enzyme retained 84.84% of its original activity during incubation at 70°C (pH 8.0) for 15 min. Lipase enzyme from G. stearothermophilus strain-5 was immobilized on various carriers and the most suitable carrier was chitin that showed 73.03% of activity yield.     

Cloning of Salmonella enterica Serovar Enteritidis Fimbrial Protein SefA as a Surface Protein in Escherichia coli Confers the Ability To Attach to Eukaryotic Cell Lines

The gene for the Salmonella enterica serovar Enteritidis fimbrial protein SefA was cloned into an Escherichia coli surface expression vector and confirmed by Western blot assay. E. coli clones expressing SefA attached to avian ovary granulosa cells and HEp-2 cells, providing evidence for the involvement of SefA in the ability of Salmonella to attach to eukaryotic cells.During the 1980s to 1990s, the worldwide increase in human Salmonella enterica serovar Enteritidis infections was associated with the consumption of contaminated eggs and egg products (13, 26, 28). In the United States, grade A shell eggs were identified as a major source contributing to Salmonella infections (19, 26, 29), and the percentage of S. Enteritidis among all Salmonella isolated from outbreaks increased from 5% to 26% from 1976 to 1996 (4). Although outbreak-associated cases due to S. Enteritidis decreased from 974 during 1998 to 2000 to 692 cases in 2004 to 2006, the 28 outbreaks in 2006 still remained above the Healthy People 2010 target of 22 (6). Despite efforts directed at reducing egg-related outbreaks, S. Enteritidis infections are still among those with the highest incidence of the seven most-reported serotypes of Salmonella (5).The large proportion of S. Enteritidis serotypes involved in food-borne outbreaks is partly attributed to the adherence elicited by surface fimbriae. Fimbriae are nonflagellar filamentous surface appendages which consist of helically arranged repeating subunit proteins called fimbrins (24). Four serologically distinct fimbriae of S. Enteritidis have been characterized according to their size (kDa) on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gels: SEF21, SEF18, SEF17, and SEF14 (9-11, 21). Fimbriae can mediate the aggregation of bacteria and their attachment to inert surfaces (2) and to the surfaces of eukaryotic cells, especially to carbohydrate receptors (8, 11, 36).SEF14 fimbriae are detected in all S. Enteritidis strains and are not widely distributed among the Enterobacteriaceae (10). These fimbriae consist of a repeating major subunit protein of 14.3 kDa (SefA) encoded by the gene sefA (9, 33). The results of studies by Peralta et al. (25) and Thiagarajan et al. (31) indicate that SEF14 fimbriae may have a role in pathogenesis by mediating attachment to eukaryotic cells. We focused on SEF14 fimbriae because of their limited distribution and their role as a main immunological target in the serological response to infection by S. Enteritidis in chickens (12). The objectives of this study were to clone and investigate the functional properties of the SEF14 fimbrin, SefA, as part of a fusion protein in Escherichia coli and to determine whether it could mediate adherence to tissue culture cells in vitro.Bacterial strains, tissue culture cells, and plasmids used in this study are described in Table ​Table1.1. Bacterial cultures were grown in LB medium (Fisher Scientific, Raleigh, NC) supplemented with 0.2% glucose and shaken at 220 revolutions min⁻¹ or in colonization factor broth (30) at 37°C. Chloramphenicol (Cm; 10 μg ml⁻¹) and ampicillin (Amp; 50 μg ml⁻¹) were added as needed (Sigma-Aldrich, St. Louis, MO). Avian ovary granulosa cells were grown in 5% CO₂ atmosphere at 37°C in M199 medium supplemented with 26 mM NaHCO₃, 0.1% bovine serum albumin, 100 U ml⁻¹ penicillin G, and 100 μg ml⁻¹ streptomycin sulfate (Gibco-BRL, Gaithersburg, MD). HEp-2 cells were obtained from ATCC (Rockville, MD) and grown in 5% CO₂ atmosphere at 37°C in minimum essential medium (Sigma-Aldrich), pH 7.2, supplemented with 26 mM NaHCO₃, 7% fetal bovine serum, 100 U ml⁻¹ penicillin G, and 100 μg ml⁻¹ streptomycin sulfate (Gibco-BRL and Sigma-Aldrich).

TABLE 1.

Bacterial strains, tissue culture cells, and plasmids

Benzene and dopamine catechol quinones could initiate cancer or neurogenic disease

Catechol quinones of estrogens react with DNA by 1,4-Michael addition to form depurinating N3Ade and N7Gua adducts. Loss of these adducts from DNA creates apurinic sites that can generate mutations leading to cancer initiation. We compared the reactions of the catechol quinones of the leukemogenic benzene (CAT-Q) and N-acetyldopamine (NADA-Q) with 2′-deoxyguanosine (dG) or DNA. NADA was used to prevent intramolecular cyclization of dopamine quinone. Reaction of CAT-Q or NADA-Q with dG at pH 4 afforded CAT-4-N7dG or NADA-6-N7dG, which lost deoxyribose with a half-life of 3 h to form CAT-4-N7Gua or 4 h to form NADA-6-N7Gua. When CAT-Q or NADA-Q was reacted with DNA, N3Ade adducts were formed and lost from DNA instantaneously, whereas N7Gua adducts were lost over several hours. The maximum yield of adducts in the reaction of CAT-Q or NADA-Q with DNA at pH 4 to 7 was at pH 4. When tyrosinase-activated CAT or NADA was reacted with DNA at pH 5 to 8, adduct levels were much higher (10- to 15-fold), and the highest yield was at pH 5. Reaction of catechol quinones of natural and synthetic estrogens, benzene, naphthalene, and dopamine with DNA to form depurinating adducts is a common feature that may lead to initiation of cancer or neurodegenerative disease.     

Factors controlling the effect of praziquantel on liver fibrosis in Schistosoma mansoni-infected patients

An association study of a cohort of 177 Sudanese patients infected with Schistosoma mansoni [82 (46%) males and 95 (54%) females] was conducted to evaluate the factors controlling the regression of liver fibrosis 39 months after treatment with praziquantel using ultrasound evaluation. Periportal fibrosis (PPF) was regressed in 63 (35.6%) patients, while the disease progressed to higher grades in 24 (13.6%) patients. The grade of PPF did not change in 90 (50.8%) patients. The mean values of portal vein diameter, splenic vein diameter and index liver size in subjects in whom PPF regressed after treatment were significantly lower than in subjects in whom the disease was progressed ( P <0.0001, P =0.031 and P =0.003, respectively). The progression of hepatic fibrosis in males (15, 8.5%) was greater than that in females (9, 5.1%). Patients with regression or progression phenotypes tend to cluster in certain families. Our study indicated that regression, progression and stabilization of PPF after praziquantel therapy is controlled by gender, age, grade of fibrosis and possibly inherited factors.     

Microwave-assisted synthesis and characterization of optically active poly (ester-imide)s incorporating l-alanine

Pyromellitic dianhydride (1) was reacted with L-alanine (2) to result [N,N′-(pyromellitoyl)-bis-l-alanine diacid] (3). This compound (3) was converted to N,N′-(pyromellitoyl)-bis-l-alanine diacyl chloride (4) by reaction with thionyl chloride. The microwave-assisted polycondensation of this diacyl chloride (4) with polyethyleneglycol-diol (PEG-200) and/or three synthetic aromatic diols furnish a series of new PEIs and Co-PEIs in a laboratory microwave oven (Milestone). The resulting polymers and copolymers have inherent viscosities in the range of 0.31–0.53 dl g⁻¹. These polymers are optically active, thermally stable and soluble in polar aprotic solvents such as DMF, DMSO, NMP, DMAc, and sulfuric acid. All of the above polymers were fully characterized by IR spectroscopy, ¹H NMR spectroscopy, elemental analyses, specific rotation and thermal analyses. Some structural characterizations and physical properties of these optically active PEIs and Co-PEIs have been reported.     

Use of multiple‐locus variable number tandem repeat analysis and phage typing for subtyping ofSalmonella Enteritidis from sporadic human cases in the United States

Aims: To investigate the genetic diversity among S. Enteritidis isolates from different geographic regions to evaluate the relationship between phage types (PTs) and variable number tandem repeat analysis (VNTR) loci. Methods and Results: We performed multiple‐locus variable number tandem repeat analysis (MLVA) and phage typing on 245 S. Enteritidis isolates collected from sporadic human clinical cases in Michigan, Minnesota, New York, and Washington states between 2000 and 2007. Ninety‐four MLVA types and 22 different PTs were identified. Specific PTs were associated with a predominant allele for certain VNTR loci. Cluster analysis using a minimum‐spanning tree demonstrated two major clusters (I, II) and one minor cluster of isolates. PTs 8, 13a, 13 and 34 were significantly associated with MLVA cluster I. Phage types 1, 4, 6a, and 18 were significantly associated with MLVA cluster II. Conclusions: We found significant association between MLVA‐based clusters and PTs. Certain VNTR loci were associated with specific PTs and could serve as useful molecular markers for S. Enteritidis in epidemiological investigations. Significance and Impact of the Study: MLVA genotyping in combination with phage typing can be used for effective characterization of S. Enteritidis isolates. It can also be useful for tracing possible sources during investigations of sporadic and outbreak cases of S. Enteritidis.