92 research outputs found

    Preliminary notes on invasion and proliferation of foodborne Listeria monocytogenes strains

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    In this study, virulence properties of L. monocytogenes strains isolated from food and food environments were evaluated. In particular, adhesion and invasion efficiencies were tested in a cell culture model (HeLa). Half of the isolates (9/18) exhibited a high invasion index. In particular, the strain isolated from smoked salmon had the highest invasion index. The remaining isolates showed an intermediate invasion index. All environmental isolates belonged to this group. Finally, no isolates revealed a low invasion index. Regarding intracellular growth, all tested isolates had a replication time between 2 and 6 hours. For this reason, they can be considered virulent. In spite of its capability to invade HeLa cells with a medium/high invasion index, a non-haemolytic rabbit isolate did not show any intracellular growth. In conclusion, differences in invasion efficiency and intracellular growth did not seem strictly related to the origin of the strains. Moreover, invasiveness of an organism is not the only requirement for establishing an infection. Virulence of L. monocytogenes also depends on ability to grow intracellularly and to spread from cell to cell. For these reasons, PCR detection of known virulence genes has the potential to gain additional insight into their pathogenic potential. A comprehensive comparative virulence characterization of different L. monocytogenes strains in studies that include tissue culture models and PCR detection of virulence genes will be necessary to investigate differences in human-pathogenic potentials among the subtypes of this bacterium

    Platelet-derived growth factor C and calpain-3 are modulators of human melanoma cell invasiveness.

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    The molecular mechanisms responsible for the elevated metastatic potential of malignant melanoma are still not fully understood. In order to shed light on the molecules involved in the acquisition by melanoma of a highly aggressive phenotype, we compared the gene expression profiles of two cell clones derived from the human cutaneous metastatic melanoma cell line M14: a highly invasive clone (M14C2/MK18) and a clone (M14C2/C4) with low ability to invade the extracellular matrix (ECM). The highly invasive phenotype of M14C2/MK18 cells was correlated with overexpression of neuropilin-1, activation of a vascular endothelial growth factor (VEGF)-A/VEGFR-2 autocrine loop and secretion of matrix metalloprotease-2. Moreover, in an in vivo murine model, M14C2/MK18 cells displayed a higher growth rate as compared with M14C2/C4 cells, even though in vitro both clones possessed comparable proliferative potential. Microarray analysis in M14C2/MK18 cells showed a strong upregulation of platelet-derived growth factor (PDGF)-C, a cytokine that contributes to angiogenesis, and downregulation of calpain-3, a calcium-dependent thiol-protease that regulates specific signalling cascade components. Inhibition of PDGF-C with a specific antibody resulted in a significant decrease in ECM invasion by M14C2/MK18 cells, confirming the involvement of PDGF-C in melanoma cell invasiveness. Moreover, the PDGF-C transcript was found to be upregulated in a high percentage of human melanoma cell lines (17/20), whereas only low PDGF-C levels were detected in a few melanocytic cultures (2/6). By contrast, inhibition of calpain-3 activity in M14C2/C4 control cells, using a specific chemical inhibitor, markedly increased ECM invasion, strongly suggesting that downregulation of calpain-3 plays a role in the acquisition of a highly invasive phenotype. The results indicate that PDGF-C upregulation and calpain-3 downregulation are involved in the aggressiveness of malignant melanoma and suggest that modulators of these proteins or their downstream effectors may synergise with VEGF‑A therapies in combating tumour-associated angiogenesis and melanoma spread

    Influence of MLH1 on colon cancer sensitivity to poly(ADP-ribose) polymerase inhibitor combined with irinotecan

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    Poly(ADP-ribose) polymerase inhibitors (PARPi) are currently evaluated in clinical trials in combination with topoisomerase I (Top1) inhibitors against a variety of cancers, including colon carcinoma. Since the mismatch repair component MLH1 is defective in 10-15% of colorectal cancers we have investigated whether MLH1 affects response to the Top1 inhibitor irinotecan, alone or in combination with PARPi. To this end, the colon cancer cell lines HCT116, carrying MLH1 mutations on chromosome 3 and HCT116 in which the wildtype MLH1 gene was replaced via chromosomal transfer (HCT116+3) or by transfection of the corresponding MLH1 cDNA (HCT116 1-2) were used. HCT116 cells or HCT116+3 cells stably silenced for PARP-1 expression were also analysed. The results of in vitro and in vivo experiments indicated that MLH1, together with low levels of Top1, contributed to colon cancer resistance to irinotecan. In the MLH1-proficient cells SN-38, the active metabolite of irinotecan, induced lower levels of DNA damage than in MLH1-deficient cells, as shown by the weaker induction of Îł-H2AX and p53 phosphorylation. The presence of MLH1 contributed to induce of prompt Chk1 phosphorylation, restoring G2/M cell cycle checkpoint and repair of DNA damage. On the contrary, in the absence of MLH1, HCT116 cells showed minor Chk1 phosphorylation and underwent apoptosis. Remarkably, inhibition of PARP function by PARPi or by PARP-1 gene silencing always increased the antitumor activity of irinotecan, even in the presence of low PARP-1 expression

    La llicenciatura en Física: Perfil de la professió. Estudi d’inserció professional

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    Les oportunitats professionals dels llicenciats i llicenciades en Física han evolucionat molt en el passat immediat, i també s’ha ampliat els tipus de sectors laborals que enrolen físics. Fa just trenta anys, la major part dels titulats era absorbida pel sector de l’ensenyament secundari i superior. Una minoria aconseguia fer carrera de recerca, principalment en centres acadèmics. En l’actualitat el panorama ha canviat força ja que, com revelen algunes enquestes a graduats recents de mitjan els anys noranta, la sortida professional de l’ensenyament només representava un 50 % del total

    The association between alcohol use, alcohol use disorders and tuberculosis (TB). A systematic review

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    <p>Abstract</p> <p>Background</p> <p>In 2004, tuberculosis (TB) was responsible for 2.5% of global mortality (among men 3.1%; among women 1.8%) and 2.2% of global burden of disease (men 2.7%; women 1.7%). The present work portrays accumulated evidence on the association between alcohol consumption and TB with the aim to clarify the nature of the relationship.</p> <p>Methods</p> <p>A systematic review of existing scientific data on the association between alcohol consumption and TB, and on studies relevant for clarification of causality was undertaken.</p> <p>Results</p> <p>There is a strong association between heavy alcohol use/alcohol use disorders (AUD) and TB. A meta-analysis on the risk of TB for these factors yielded a pooled relative risk of 2.94 (95% CI: 1.89-4.59). Numerous studies show pathogenic impact of alcohol on the immune system causing susceptibility to TB among heavy drinkers. In addition, there are potential social pathways linking AUD and TB. Heavy alcohol use strongly influences both the incidence and the outcome of the disease and was found to be linked to altered pharmacokinetics of medicines used in treatment of TB, social marginalization and drift, higher rate of re-infection, higher rate of treatment defaults and development of drug-resistant forms of TB. Based on the available data, about 10% of the TB cases globally were estimated to be attributable to alcohol.</p> <p>Conclusion</p> <p>The epidemiological and other evidence presented indicates that heavy alcohol use/AUD constitute a risk factor for incidence and re-infection of TB. Consequences for prevention and clinical interventions are discussed.</p

    The complete idiot's guide to the perfect job interview

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    Stable Carbon and Nitrogen Analysis: A Comparison of Modern Calculus, Hair and Fingernail

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    Stable carbon and nitrogen isotope analysis has been used to reflect dietary signatures in humans and animals. For ancient human remains, bone collagen and bone apatite are the traditional biomaterials used to estimate stable isotope ratios. For modern populations, hair and fingernail are used toward this end. Recent work indicates that dental calculus from ancient remains may be another viable biomaterial for stable isotope analysis. Because its collection is technically non-destructive, the use of dental calculus for stable isotope analysis could have benefits in cases where destructive analysis is prohibited. To help establish the utility of calculus as an isotope proxy, the present research analyzed modern calculus, along with the established biomaterials of hair and fingernail, to determine the extent to which they yield comparable isotope ratios. The analysis shows there is a strong and significant correlation between the stable carbon isotope ratios of modern calculus, hair and fingernails. In contrast, there is no correlation for stable nitrogen isotope ratios between calculus and either hair or nail. Based on the high weight percentages of carbon and nitrogen in some calculus samples, these findings may be complicated by components in plaque and saliva

    Establishing a Breakfast Club in the University

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    Considered as the most important meal of the day, breakfast when taken daily improves the health, mood and productivity of individuals. This quantitative descriptive study assessed the needs of students for breakfast with the aim of establishing a breakfast club in the university. This study was conducted among 475 students of the University of Cebu Lapu-Lapu and Mandaue, Mandaue City, Cebu, Philippines. The study employed the descriptive, quantitative approach. A researcher-made questionnaire was used to gather data. Data collection was done from January 2016 to December 2016. Treatment of data used were simple percentage, weighted mean, and sum of ranks. Majority of the respondents were female (55.2%), college level (76.2%), and residents of Lapu-Lapu City (54.5%). the students do not take breakfast before going to school (63.6%). If food is available at home, they prefer to take their breakfast from 6:00 AM to 7:00 AM (21.9%). Only 4 items are moderately preferred. This includes: one glass of water; one piece of egg (boiled, scrambled or sunny side up); one glass of milk or hot chocolate drink; and one piece of banana or any kind of fruit equivalent to 60 grams. On the 5th spot is 1 cup of rice or its equivalent (less preferred). Based on the findings of the study, there is a need to establish a breakfast club in the university. This program shall support the nutritional requirements of students to help them excel in class. Food preferences and breakfast time shall be considered in the implementation of the program. Recommended citation: Dorio, P. A. Jr. &amp; Amparado, M. A. P. (2020). Establishing a Breakfast Club in the University. Cebu Journal of Hospitality and Tourism and Management, 1(1), 90-100
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