Anaerobic biodegradation of high-molecular-weight polycyclic aromatic hydrocarbons by a facultative anaerobe Pseudomonas sp. JP1

Polycyclic aromatic hydrocarbons (PAHs) are harmful persistent organic pollutants, while the high-molecular-weight (HMW) PAHs are even more detrimental to the environment and human health. However, microbial anaerobic degradation of HMW PAHs has rarely been reported. One facultative anaerobe Pseudomonas sp. JP1 was isolated from Shantou Bay, Shantou, China, which could degrade a variety of HMW PAHs. After 40 days cultivation with strain JP1, anaerobic biodegradation rate of benzo[a]pyrene (BaP), fluoranthene, and phenanthrene was 30, 47, and 5 %, respectively. Consumption of nitrate as the electron acceptor was confirmed by N-(1-naphthyl) ethylenediamine spectrophotometry. Supplementation of sodium sulfite, maltose, or glycine, and in a salinity of 0–20 ‰ significantly stimulated anaerobic degradation of BaP. Lastly, the anaerobic degradation metabolites of BaP by strain JP1 were investigated using GC/MS, and the degradation pathway was proposed. This study is helpful for further studies on the mechanism of anaerobic biodegradation of PAHs.     

Apparent Reduction of ADAM10 in Scrapie-Infected Cultured Cells and in the Brains of Scrapie-Infected Rodents

It has been described that A disintegrin and metalloproteinase (ADAM10) may involve in the physiopathology of prion diseases, but the direct molecular basis still remains unsolved. In this study, we confirmed that ADAM10 was able to cleave recombinant human prion protein in vitro. Using immunoprecipitation tests (IP) and immunofluorescent assays (IFA), reliable molecular interaction between the native cellular form of PrP (PrP^C) and ADAM10 was observed not only in various cultured neuronal cell lines but also in brain homogenates of healthy hamsters and mice. Only mature ADAM10 (after removal of its prodomain) molecules showed the binding activity with the native PrP^C. Remarkably more prion protein (PrP)-ADAM10 complexes were detected in the membrane fraction of cultured cells. In the scrapie-infected SMB cell model, the endogenous ADAM10 levels, especially the mature ADAM10, were significantly decreased in the fraction of cell membrane. IP and IFA tests of prion-infected SMB-S15 cells confirmed no detectable PrP-ADAM10 complex in the cellular lysates and PrP-ADAM10 co-localization on the cell surface. Furthermore, we demonstrated that the levels of ADAM10 in the brain homogenates of scrapie agent 263K-infected hamsters and agent ME7-infected mice were also almost diminished at the terminal stage, showing time-dependent decreases during the incubation period. Our data here provide the solid molecular basis for the endoproteolysis of ADAM10 on PrP molecules and interaction between ADAM10 and PrP^C. Obvious loss of ADAM10 during prion infection in vitro and in vivo highlights that ADAM10 may play essential pathophysiological roles in prion replication and accumulation.     

Study of enhancement and inhibition phenomena and genes relating to degradation of petroleum polycyclic aromatic hydrocarbons in isolated bacteria

Polycyclic aromatic hydrocarbons (PAHs) are xenobiotic compounds, which being degraded by chemical, physical or biological methods. The latter is the safest and the cheapest one. Two bacterial strains ASU-01 and ASU-016 were isolated from different Egyptian petroleum contaminated sites. They were genetically identified based on the analysis of the nucleotide sequences of the 16S ribosomal PNA gene and the phylogenetic tree as Enterobacter hormaechei and Pseudomonas pseudoalcaligenes respectively. When pyrene as high molecular weight (HMW)-PAH was added as a sole carbon source, both strains could degrade it with efficiency 77.7 and 83.7% within 15 days of incubation, respectively. However, when it was mixed with low molecular weight (LMW)-PAHs, two opposite phenomena appeared. The first one was enhancement, which occurred with ASU-01. This strain shifted pyrene efficiency to 98.5%. The second phenomenon was inhibition occurred with ASU-016 which completely retarded pyrene degradation. Naphthalene dioxygenase (nahAc), and catechol dioxygenases (C12O and C23O) genes were detected in the two strains based on PCR. The detected genes were confirmed by determining the different specific activities of their translated protein (enzymes) on different PAHs. The maximum values of biosurfacatant production activity and cell-surface and percentage of cell-surface hydrophobicity (CSH) were detected during the exponential phase. These latter factors increased the bioavailability and consequently, the assimilation of PAHs.     

Mechanism of bFGF-binding Peptide Reversing Adriamycin Resistance in Human Gastric Cancer Cells

Development of drug resistance is a challenging problem in cancer chemotherapy. It has been shown that basic fibroblast growth factor (bFGF) plays an important role in an epigenetic mechanism of drug resistance. We have isolated a bFGF binding peptide P7 with inhibitory activity against bFGF-induced proliferation of human gastric cancer cells by screening a phage display library. In this study, we found that P7 peptide also has efficacy of reversing bFGF-induced resistance to Adriamycin (ADM) in human gastric cancer cells. Further investigations with SGC-7901 cells revealed that inhibition of Akt activation triggered by bFGF, and reversal of bFGF-induced up-regulation of Bcl-2 and XIAP and down-regulation of Bax, contribute to P7 peptide counteracting the anti-apoptotic effect of bFGF, and further reversing bFGF-induced resistance to ADM. The results suggested that the bFGF-binding peptide may have therapeutic potential of drug resistance in gastric cancer.     

cDNA library construction from meristematic tissue of finger millet panicle

A protocol to obtain full-length cDNA using a SuperScript® Full-Length cDNA Library Construction Kit II (Invitrogen, United States) was developed, and a high quality cDNA library of meristem tissue of finger millet panicle (Eleusine coracana (L.) Gaertn) was constructed. The titer of the constructed cDNA library was 3.01 × 10⁵ CFU/mL, the average length of the insert was approximately 1070 base pairs, and the average efficiency of insertion of cDNA fragments was 99.5%. The sequencing of randomly selected clones created cDNA library was carried out. The cDNA sequences of clones were identified by BLAST search. The cDNA library analysis and selective sequencing indicate good functionality and full size of cDNA inserts of the clones. The constructed cDNA library from meristematic tissue of finger millet panicle is a good and reliable source for isolation and identification of key genes of metabolism and development of meristem as well for creation of new genetic markers for genetic research and molecular selection.     

Expression of TNF-α, IFN-γ, TGF-β, and IL-4 in the Spinal Tuberculous Focus and Its Impact on the Disease

To investigate the expression of TNF-α, IFN-γ, TGF-β, and IL-4 in the spinal tuberculous focus and its relationship with the lesions type, severity, and bone destruction. The pathological samples of patients with spinal tuberculosis (TB) were divided into hyperplasia group and necrosis group according to their intra-operative and post-operative pathological findings. Normal bone tissues were taken as the control group. Pathology and expression of TNF-α, IFN-γ, TGF-β, and IL-4 in different tissues were compared among these three groups using immunohistochemical staining, quantitative image analysis, and measurement of bone tissue. 286 granulomas observed in the 14 samples in the hyperplasia group, which included 84 necrotizing and 202 non-necrotizing granulomas. As for the 20 samples in the necrosis group, there were 356 necrotizing and 186 non-necrotizing granulomas among all the 542 granulomas. The proportion of necrotizing granulomas in the necrosis group was significantly higher than that of the hyperplasia group. By inter-group comparison, expression of TNF-α, IFN-γ of granulomas in the hyperplasia group was significantly higher than that of the necrosis group, while the expression of TGF-β, IL-4 of granulomas in the necrosis group was significantly higher than that of the hyperplasia group. Also, expression of IFN-γ of non-necrotizing granulomas was significantly higher than that of necrotizing granulomas in the hyperplasia group, and expression of TGF-β in necrotizing granulomas was significantly higher than that of non-necrotizing granulomas in the necrosis group. The lesions were mainly bone resorption in the hyperplasia group, whereas mostly necrotic bones accompanied by local fibrosis in the necrosis group. Expression levels of TNF-α, IFN-γ in the hyperplasia group have a positive correlation to bone loss, whereas expression levels of TGF-β, IL-4 in the necrosis group have a positive correlation to the bone formation. The high expressions of TNF-α, IFN-γ in the spinal tuberculous focus were associated with protective immune cells. TGF-β and IL-4 were related to allergic lesions, fibrosis and osteogenesis. Expression imbalance of TNF-α, IFN-γ, TGF-β, and IL-4 might aggravate the allergy of TB.     

Chemopreventive effects of curcumin on chemically induced mouse skin carcinogenesis in BK5.insulin-like growth factor-1 transgenic mice

The insulin-like growth factor-1 (IGF-1) signaling pathway is strongly associated with the risk of various cancers, and its inhibition has emerged as a potent anticancer strategy. Accumulating evidence from in vitro studies has shown that curcumin is a potent inhibitor of the IGF-1 signaling pathway. However, direct evidence that curcumin modulates IGF-1-induced tumorigenesis in a physiological system has not been reported. Therefore, in this study, we assessed the anticarcinogenic activity of curcumin on skin cancer by using BK5.IGF-1 transgenic (Tg) mice that overexpress IGF-1 in the skin epidermis. In 7,12-dimethylbenz(a)anthracene (DMBA)-tetradecanoyl phorbol-13-acetate (TPA) two-stage skin carcinogenesis, a curcumin diet (0.02% wt/wt) fed for 14 wk remarkably reduced mouse skin tumor multiplicity by 53%, epidermal hyperplasia and proliferation compared to the control diet group. TPA-induced phosphorylation of Akt, S6 kinase (S6K), and eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1) in mouse skin was lower in the curcumin group than in the control group. Curcumin treatment inhibited IGF-1-induced phosphorylation of the IGF-1 receptor, insulin receptor substrate-1, Akt, S6K, and 4EBP1 in the mouse keratinocyte cell line, C50 in a dose-dependent manner. Taken together, these data suggest that curcumin exerts significant anticarcinogenic activity in skin cancer through the inhibition of IGF-1 signaling.     

Immune Response of the VEGF/bFGF Complex Peptide Vaccine and Function of Immune Antibodies in Inhibiting Migration of HUVEC Cells and Proliferation of Cancer Cells

Overexpression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) plays a key role in tumor angiogenesis and metastasis in tumors. VEGF/bFGF complex peptide (VBP3) was designed to elicit the body to produce both high titer anti-VEGF and anti-bFGF antibodies to inhibit tumor angiogenesis and tumor growth. BALB/c mice were immunized with the VEGF/bFGF complex peptide, and the immune responses were assayed. Splenocytes were separated from the immunized mice and the CD4, CD8 T cells and IFN-γ were assayed by Flow cytometry. The results showed that the VBP3 could effectively stimulate immune response in mice and resulted in the increase of CD4 and CD8 T cells. CD4+ T cells and CD8+ T cells were increased from 10.78 to 15.13 and 6.82 to 11.58 % respectively. Polyclonal antibodies purified from the VBP3 immunized mice showed good anti-proliferation function to lung cancer cells, and resulted in the decrease of phosphroylation level of Akt and Erk assayed by the Western-blot. Transwell assays showed that the migration of HUVEC cells was inhibited by the antibodies. The results revealed that the VBP3 have good immunogenicity and may be used as a vaccine for tumor therapy.     

Impregnation of the Bacterial Cellulose Membrane with Biologically Produced Silver Nanoparticles

Different wound dressings with antibacterial property have been surveyed and one among them is bacterial cellulose (BC). Since the BC does not have antibacterial property, the biologically produced silver nanoparticles (SNPs) were impregnated into the BC. For the BC production, Hestrin–Schramm broth was used. Formation of the BC was proven by enzymatic hydrolysis. For SNPs production, the bacterial supernatant was treated with AgNO₃ and formation of SNPs was monitored through spectrophotometer, TEM and XRD. For impregnation of SNPs into the BC, the cleaned membrane was placed in the bacterial supernatant that contained 1 mmol of AgNO₃. The antibacterial assay was done for the BC/SNPs. Enzymatic hydrolysis proved the presence of the BC. Spectrophotometer and XRD results showed the formation of SNPs. TEM analysis revealed the presence of SNPs with sizes around 5–100 nm. SEM micrographs showed the impregnation of SNPs into the BC. Antibacterial test exhibited the antibacterial activity of the BC/SNPs.     

The amino-terminal sequence ofStreptomyces griseus carboxypeptidase

The amino-terminal sequence of carboxypeptidase fromStreptomyces griseus was determined using a new protocol for automatic Edman degradation that reduced background noise. The sequence of the first 48 residues is: Asp-Phe-Pro-Pro-Ala-Asp-Ser-Arg-Tyr-His-Asn-Tyr-Ala-Glu-Met-Asn-Ala-Ala-Ile-Asp-Ala-Arg-Ile-Ala-Ala-Asn-Pro-Ser-Ile-Met-Ser-Lys-Arg-Val-Ile-Gly-Lys-Thr-Tyr-Gln-Gly-(Arg)-Asp-Val-Ile-Ala-Val-Lys, which is homologous to that of other zinc-containing carboxypeptidase from vertebrate and invertebrate sources.     

Gas chromatographic-mass spectroscopic identification and quantification of cyclic guanosine-3′: 5′-monophosphate in maize seedlings (Zea mays)

Gas chromatographic-mass spectroscopic evidence is presented for the presence of guanosine-3′: 5′-monophosphate (cGMP) in maize seedlings. The amount of cGMP (35–72 pmol g^-1 fresh weight) was quantified as a tetra-silyl derivative using gas-chromatographic detection with reference to a silylated standard of authentic cGMP. Gas-chromatographic separation of tri-silyl adenosine-3′: 5′-monophosphate and tetra-silyl cGMP is demonstrated.     

Aflatoxin in human and camel milk in Abu Dhabi,United Arab Emirates

During an initial survey, using thin layer chromatography, 10 of 64 samples of mothers’ breast milk, collected from donors at the Corniche Maternity Hospital and the Al-Nehyan Clinic for Maternity and Childhood, were found to contain Aflatoxin M₁ at concentrations ranging from 0.3 to 1.3 ng mL^?1. A second survey using HPLC showed Aflatoxin M₁ at concentrations ranging from 7 to 23 pg mL^?1 in all of the 15 samples collected. 6 of 20 samples of camel milk collected from several sources in Abu Dhabi were also found to contain Aflatoxin M₁ at levels ranging from 0.25 to 0.8 ng mL^?1.     

Key enzymes of degradation and angiogenesis as factors of tumor progression for squamous-cell cervical carcinoma

Destruction of the connective tissue matrix (CTM) and angiogenesis are the two processes playing a key role in tumor progression. Matrix metalloproteinases (MMPs) play a leading role in processes of tissue destruction. Tissue collagenases MMP-1 and MT1-MMP hydrolyze fibrillar collagens constituting the base of CTM and enable tumor invasion. Gelatinases A and B (MMP-2 and MMP-9) hydrolyze type IV collagen which is the main component of basal membranes and contribute to the development of metastases. Endogenous activators and inhibitors are involved in the regulation of expression and activity of these enzymes. MMP-9 was shown to release vascular endothelial growth factor (VEGF), the principal inductor of angiogenesis, bound to CTM. Angiotensin-converting enzyme (ACE) is involved in the induction of VEGF synthesis and stimulation of endothelial cell proliferation mediated by angiotensin II (AII) and its type 1 receptor (AT1R). Experiments reported in the present article addressed the distinctive features of expression of key degradation and angiogenesis enzymes in squamous cell carcinoma (SCC) of the cervix. MMP-1, MT1-MMP, MMP-2, and MMP-9 and their endogenous regulators TIMP-1 and TIMP-2, as well as ACE, were the objects of research. Experiments were performed with clinical specimens including tumor tissue samples, for which presence or absence of metastasis to regional lymph nodes was taken into account, and morphologically normal tissue samples. Increased expression of MMP-1, MT1-MMP, and MMP-9 and decreased expression of TIMP-1 and TIMP-2 were shown to make the principal contribution to the destructive (invasive) potential of cervical carcinomas; the effect of changes in MMP-2 expression was less pronounced. Dramatically increased expression of MMP-1 and MMP-9 was evident in metastasizing tumors. ACE activity in tumor samples was generally higher than activity in normal tissue. Substantial expression of MMP-1, MMP-2, MMP-9, and ACE was detected in morphologically normal tissue adjacent to the tumor; this can contribute to increased destructive potential of a tumor. The data reported are important for understanding the mechanisms of tumor progression, have prognostic value, and may affect the choice of individual therapeutic strategy for the patients.     

Adaptive Combiner for MapReduce on cloud computing

MapReduce is a programming model to process a massive amount of data on cloud computing. MapReduce processes data in two phases and needs to transfer intermediate data among computers between phases. MapReduce allows programmers to aggregate intermediate data with a function named combiner before transferring it. By leaving programmers the choice of using a combiner, MapReduce has a risk of performance degradation because aggregating intermediate data benefits some applications but harms others. Now, MapReduce can work with our proposal named the Adaptive Combiner for MapReduce (ACMR) to automatically, smartly, and trainer for getting a better performance without any interference of programmers. In experiments on seven applications, MapReduce can utilize ACMR to get the performance comparable to the system that is optimal for an application.