Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 9 de 9
Filter
Add more filters










Database
Language
Publication year range
1.
Cell Biol Int ; 46(10): 1661-1671, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35819094

ABSTRACT

The interaction of cancer cells with their tumor microenvironment determines key events in the progression of the disease, therapeutic efficacy, and the development of drug resistance. Here, we presented evidence that tamoxifen support breast cancer growth during nutrition deprivation by modulating mitochondrial dynamics through AMPK and MAPK signaling. Tamoxifen enhances mitochondrial fusion under nutrition-deprived conditions by suppressing Drp1 ser616 phosphorylation and upregulating Mfn1 levels. Tamoxifen-induced mitochondrial fusion is mediated by the activation of AMPK as evident by the pharmacological inhibition of AMPK reverse mitochondrial fusion. Interestingly, JNK activation by tamoxifen controls the mitochondrial fusion morphology by downregulating Mfn2. Collectively, tamoxifen support cell growth by enhancing mitochondrial fusion by regulating stress kinase signaling under nutrition deprivation condition.


Subject(s)
Mitochondrial Dynamics , Tamoxifen , AMP-Activated Protein Kinases/metabolism , Humans , Mitochondrial Dynamics/physiology , Phosphorylation , Signal Transduction , Tamoxifen/pharmacology
2.
Sci Rep ; 6: 21367, 2016 Feb 17.
Article in English | MEDLINE | ID: mdl-26883288

ABSTRACT

The present study aimed at the molecular characterization of pathogenic and non pathogenic F. oxysporum f. sp. lycopersici strains isolated from tomato. The causal agent isolated from symptomatic plants and soil samples was identified based on morphological and molecular analyses. Pathogenicity testing of 69 strains on five susceptible tomato varieties showed 45% of the strains were highly virulent and 30% were moderately virulent. Molecular analysis based on the fingerprints obtained through ISSR indicated the presence of wide genetic diversity among the strains. Phylogenetic analysis based on ITS sequences showed the presence of at least four evolutionary lineages of the pathogen. The clustering of F. oxysporum with non pathogenic isolates and with the members of other formae speciales indicated polyphyletic origin of F. oxysporum f. sp. lycopersici. Further analysis revealed intraspecies variability and nucleotide insertions or deletions in the ITS region among the strains in the study and the observed variations were found to be clade specific. The high genetic diversity in the pathogen population demands for development of effective resistance breeding programs in tomato. Among the pathogenic strains tested, toxigenic strains harbored the Fum1 gene clearly indicating that the strains infecting tomato crops have the potential to produce Fumonisin.


Subject(s)
Fusarium/classification , Fusarium/physiology , Phylogeny , Plant Diseases/microbiology , DNA, Intergenic , Genetic Variation , Genotype , Solanum lycopersicum/microbiology , Microsatellite Repeats , Molecular Typing , Virulence
3.
J Chem Phys ; 142(22): 224301, 2015 Jun 14.
Article in English | MEDLINE | ID: mdl-26071704

ABSTRACT

We have performed extensive calculations to investigate thermal energy, rotationally inelastic collisions of NaK (A(1)Σ(+)) with He. We determined a potential energy surface using a multi-reference configuration interaction wave function as implemented by the GAMESS electronic structure code, and we have performed coupled channel scattering calculations using the Arthurs and Dalgarno formalism. We also calculate the Grawert coefficients B(λ)(j, j') for each j → j' transition. These coefficients are used to determine the probability that orientation and alignment are preserved in collisions taking place in a cell environment. The calculations include all rotational levels with j or j' between 0 and 50, and total (translational and rotational) energies in the range 0.0002-0.0025 a.u. (∼44-550 cm(-1)). The calculated cross sections for transitions with even values of Δj tend to be larger than those for transitions with odd Δj, in agreement with the recent experiments of Wolfe et al. (J. Chem. Phys. 134, 174301 (2011)). The calculations of the energy dependence of the cross sections and the calculations of the fraction of orientation and alignment preserved in collisions also exhibit distinctly different behaviors for odd and even values of Δj. The calculations also indicate that the average fraction of orientation or alignment preserved in a transition becomes larger as j increases. We interpret this behavior using the semiclassical model of Derouard, which also leads to a simple way of visualizing the distribution of the angles between the initial and final angular momentum vectors j and j'. Finally, we compare the exact quantum results for j → j' transitions with results based on the simpler, energy sudden approximation. That approximation is shown to be quite accurate.

4.
Lett Appl Microbiol ; 58(5): 414-22, 2014 May.
Article in English | MEDLINE | ID: mdl-24313443

ABSTRACT

UNLABELLED: Aspergillus section Flavi is a heterogeneous fungal cluster including some of the most economically important Aspergillus species. The section is comprised of toxigenic and nontoxigenic aspergilli that are phenotypically undistinguishable. The aim of this study was to develop a genetic marker specific to Aspergillus section Flavi on the whole. Based on inter-simple sequence repeat (ISSR) fingerprinting profiles of major Aspergillus section Flavi members, a sequence-characterized amplified region (SCAR) marker was identified. Primers were designed in the conserved regions of the SCAR marker and were utilized in a PCR for concurrent identification of major members of the section. The detection level of the SCAR-PCR was found to be 0·1 ng purified DNA, and when applied to 45 naturally contaminated food samples, 28 samples were found infected with Aspergillus section Flavi members. The present SCAR-PCR is rapid and less cumbersome unlike conventional identification techniques. SIGNIFICANCE AND IMPACT OF THE STUDY: Identification of Aspergillus section Flavi members is important owing to their impact on human health and economy. The ISSR-based SCAR-PCR developed in this study is superior over the other existing Aspergillus section Flavi detection systems due to its simplicity and minimal requirement of sample handling. This PCR could be a supplementary strategy to time-consuming and rather ambiguous conventional polyphasic detection techniques and a reliable tool for high-throughput sample analysis.


Subject(s)
Aspergillus flavus/genetics , Aspergillus flavus/isolation & purification , Polymerase Chain Reaction/methods , Aflatoxins/biosynthesis , Aspergillus flavus/classification , DNA, Fungal/genetics , Humans , Microsatellite Repeats
5.
FEMS Microbiol Lett ; 340(2): 93-100, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23278425

ABSTRACT

Staphylococcus aureus and Clostridium perfringens are two major bacteria that infect open wounds and delay the healing process. The rapid and progressive deterioration of soft tissue during S. aureus and C. perfringens coinfections is due to analogous necrotic alpha toxins produced by the two organisms. The aim of this study was to determine the alpha toxins of S. aureus and C. perfringens by duplex PCR. The PCR assay employed two sets of primers: hlaf/r to amplify staphylococcal alpha toxin gene hla (274 bp) and cpaf/r to amplify clostridial alpha toxin gene cpa (398 bp) along with a competitive internal amplification control (608 bp), simultaneously. Optimization of the duplex PCR assay was achieved by a modified Taguchi method, an engineering optimization process, in a nine-tube combinatorial array. The detection level of the duplex PCR was found to be 10 pg of purified DNA or 10(3 ) CFU mL(-1) of S. aureus and 100 pg of purified DNA or 10(4)  CFU mL(-1) of C. perfringens. Other bacteria routinely found in tissue infections were tested for cross-reactivity and the duplex PCR turned out to be highly specific. This duplex PCR assay provides a rapid, robust and reliable alternative to the existing conventional techniques in establishing the aetiology of S. aureus and C. perfringens in soft tissue infections.


Subject(s)
Bacterial Toxins/genetics , Clostridium perfringens/metabolism , Polymerase Chain Reaction/methods , Staphylococcus aureus/metabolism , Bacterial Toxins/metabolism , Clostridium Infections/microbiology , Clostridium perfringens/genetics , Clostridium perfringens/isolation & purification , DNA Primers/genetics , Humans , Staphylococcal Infections/microbiology , Staphylococcus aureus/genetics , Staphylococcus aureus/isolation & purification
6.
J Appl Microbiol ; 114(3): 819-27, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23216688

ABSTRACT

AIM: To develop and evaluate a multiplex polymerase chain reaction assay (mPCR) for the concurrent detection of four major mycotoxin metabolic pathway genes, viz. nor1 (aflatoxin), Tri6 (trichothecene), FUM13 (fumonisin) and otanps (ochratoxin A). METHODS AND RESULTS: A mPCR assay with competitive internal amplification control, employing specific primers for each of the aforementioned four genes, was optimized and validated using 10 reference strains and 60 pure culture isolates. The standardized mPCR assay detected all four mycotoxin metabolic genes in artificially contaminated maize samples with a sensitivity of 2 × 10(3) CFU g(-1) for nor1-positive Aspergillus strains, Tri6 and FUM13-positive Fusarium strains and 2 × 10(4) CFU g(-1) for otanps-positive Penicillium strains. When the developed mPCR assay was applied to 40 natural foods, 35% (14 of 40) of the samples were contaminated with either one or more mycotoxins. The mPCR results were further evaluated with high-performance liquid chromatography (HPLC), and in general, both the methods provided unequivocal results. CONCLUSION: The current mPCR assay is a rapid and reliable tool for simultaneous specific and sensitive detection of aflatoxigenic Aspergillus strains, trichothecene- and fumonisin-producing Fusarium strains, and ochratoxigenic Penicillium species from naturally contaminated foods. SIGNIFICANCE AND IMPACT OF THE STUDY: This mPCR assay could be a supplementary strategy to current conventional mycotoxin analytical techniques such as thin-layer chromatography (TLC), high performance thin layer chromatography, HPLC, etc., and a reliable tool for high-throughput monitoring of major mycotoxin-producing fungi during the processing steps of food and feed commodities.


Subject(s)
Aspergillus/isolation & purification , Food Contamination/analysis , Food Microbiology/methods , Fusarium/isolation & purification , Multiplex Polymerase Chain Reaction/methods , Penicillium/isolation & purification , Aspergillus/genetics , Chromatography, High Pressure Liquid , DNA Primers , DNA, Fungal/genetics , Fumonisins/analysis , Fusarium/genetics , Multiplex Polymerase Chain Reaction/standards , Mycotoxins/analysis , Ochratoxins/analysis , Penicillium/genetics , Sensitivity and Specificity , Trichothecenes/analysis
7.
J Appl Microbiol ; 113(2): 448-58, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22563989

ABSTRACT

AIM: To evaluate an inter-generic recombinant alpha domain fusion protein for simultaneous detection and neutralization of Clostridium perfringens and Staphylococcus aureus alpha toxins. METHODS AND RESULTS: Truncated portions of clostridial and staphylococcal alpha haemolysin genes were PCR amplified and linked to each other through a hydrophilic flexible Glycine linker sequence using overlap-extension PCR to form a chimeric gene αCS. The recombinant αCS fusion protein was expressed and characterized for its toxicity, cell binding capacity and haemolysis inhibition properties. The fusion protein was nontoxic and effectively retarded staphylococcal alpha haemolysis, probably by competitively interacting with putative staphylococcal alpha haemolysin receptors on erythrocytes. Murine hyperimmune polysera raised against r-αCS specifically detected 42-kDa and 33-kDa proteins when culture supernatants of Cl. perfringens (clostridial alpha toxin) and Staph. aureus (staphylococcal alpha toxin), respectively, were analysed in Western blot. The polyclonal antisera effectively diminished the haemolytic action of both the wild-type toxins in vitro. CONCLUSIONS: The r-αCS fusion protein was nontoxic competitive inhibitor of staphylococcal alpha haemolysin. The protein elicited specific immune response against Cl. perfringens and Staph. aureus alpha toxins. The antisera also neutralized the toxicities of both the native wild-type toxins in vitro. SIGNIFICANCE OF THE STUDY: The bivalent recombinant αCS protein could be a novel intervention in the field of diagnostics and therapeutics against Cl. perfringens and Staph. aureus infections, particularly, in case of co-infections like gangrenous ischaemia, gangrenous mastitis, etc.


Subject(s)
Bacterial Toxins/antagonists & inhibitors , Calcium-Binding Proteins/antagonists & inhibitors , Hemolysin Proteins/antagonists & inhibitors , Recombinant Fusion Proteins/pharmacology , Type C Phospholipases/antagonists & inhibitors , Animals , Bacterial Toxins/genetics , Blotting, Western , Calcium-Binding Proteins/genetics , Enzyme-Linked Immunosorbent Assay , Erythrocytes/drug effects , Female , Hemolysin Proteins/genetics , Immune Sera/pharmacology , Mice , Mice, Inbred BALB C , Polymerase Chain Reaction , Recombinant Fusion Proteins/genetics , Type C Phospholipases/genetics
8.
Br J Dermatol ; 161(1): 78-89, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19416233

ABSTRACT

BACKGROUND: Hair follicle (HF) ostia represent a potential port of microbial entry into the skin. However, they rarely show clinical signs of infection. This suggests the presence of local, efficient, antimicrobial defence systems, which may include antimicrobial peptides (AMPs). OBJECTIVES: We determined the presence and distribution of the major AMPs, RNase 7 and psoriasin (S100A7), in human scalp HFs. We investigated whether HF production of these AMPs was induced by prototypic microbial products and proinflammatory cytokines, i.e. interferon (IFN)-gamma. Finally, we examined whether the classical pathways for AMP induction, such as toll-like receptor (TLR)4 and TLR5 expression, are present in human HFs and up-regulated after stimulation with bacterium-associated ligands. METHODS: Cryosections from fresh or organ-cultured full-thickness normal human scalp skin treated with lipopolysaccharide (LPS), flagellin, protein A, lipoteichoic acid (LTA) or IFN-gamma were stained for psoriasin and RNase 7 immunoreactivity (IR) as well as for TLR4 and TLR5. In addition, outer root sheath cell culture and semiquantitative analysis of mRNA expression levels of RNase 7 and psoriasin were performed. RESULTS: Specific RNase 7 IR was present throughout the entire HF outer root sheath in situ and in cell culture, whereas psoriasin IR was present only in the most distal compartment and not detectable in cultured ORS cells. Upon treatment with Gram-positive (LTA, protein A) or Gram-negative bacterial (LPS, flagellin) cell wall components, or with the cytokine IFN-gamma, the IR of both psoriasin and RNase 7 was modified. TLR4 and TLR5 IR was detected in the normal HF epithelium and were upregulated after treatment with their respective ligand. The mRNA analysis confirmed the immunohistochemistry results. CONCLUSIONS: This pilot study suggests that normal human scalp HF epithelium possesses a functional antimicrobial defence system, which includes the AMPs RNase 7 and psoriasin, and TLRs, and that these are induced by classical microbial products.


Subject(s)
Calcium-Binding Proteins/metabolism , Hair Follicle/metabolism , Ribonucleases/metabolism , Aged , Epithelium/immunology , Epithelium/metabolism , Female , Hair Follicle/drug effects , Hair Follicle/immunology , Humans , Immunohistochemistry , Interferon-gamma/pharmacology , Lipopolysaccharides/pharmacology , Middle Aged , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction , S100 Calcium Binding Protein A7 , S100 Proteins , Toll-Like Receptor 4/metabolism , Up-Regulation/drug effects
9.
Indian J Cancer ; 45(4): 158-63, 2008.
Article in English | MEDLINE | ID: mdl-19112204

ABSTRACT

BACKGROUND: There is general belief that patients who enrolled on a clinical trial have better outcomes compared to those who are treated outside of a trial. We analyzed if there was a 'trial effect' for patients with advanced non-small cell lung cancer (NSCLC) treated with chemotherapy. MATERIALS AND METHODS: A retrospective analysis of cohorts of patients with advanced NSCLC who received chemotherapy inside and outside of a clinical trial were analyzed for response rates (RR), progression free survival (PFS), overall survival (OS), 1 and 2 year survival. RESULTS: There were 194 patients who received chemotherapy of which, 54 were on a clinical trial and 140 outside of it. For the whole group, the RR, median PFS, OS, one and two-year survivals were 35.4%, six months (range, 2-70), seven months (range, 2-72), 29.8% and 9.7% respectively. The differences in RR and PFS of patients who were treated inside and outside of a clinical trial were not significant (P=0.6164, 0.0881). The differences in median OS and one-year survivals between the groups were significant (P=0.0052, 0.022). For the whole group, patients who received II line chemotherapy had better OS (P< or = 0.0001). More patients in the trial group received II line chemotherapy (P=0.0004).The difference in the median OS between the groups continued to be significant even after patients who received II line chemotherapy were censored (P=0.0437). CONCLUSION: Patients with advanced NSCLC who were treated inside of a clinical trial had better OS compared to those who were treated outside of it.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Patient Participation , Adolescent , Adult , Aged , Aged, 80 and over , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/radiotherapy , Combined Modality Therapy , Disease-Free Survival , Female , Humans , Lung Neoplasms/pathology , Lung Neoplasms/radiotherapy , Male , Middle Aged , Multicenter Studies as Topic , Neoplasm Staging , Organoplatinum Compounds/therapeutic use , Randomized Controlled Trials as Topic , Research Design , Survival Rate , Treatment Outcome , Young Adult
SELECTION OF CITATIONS
SEARCH DETAIL
...