16 research outputs found

    Engineering microbial cells for biometallic catalysis

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    This study investigates the use of palladised Escherichia coli as a biometallic catalyst with a view to its use in deracemisation reactions. Some bacteria can reduce metals by their use as the terminal electron acceptor in the respiratory chain, and recent work using Desulfovibrio spp. has led to the generation of a palladium bionanocatalyst with superior activity to commercially available carbon-supported Pd(0) nanoparticles. This current study has investigated the use of formate as an electron donor for the reduction of soluble Pd(II) to insoluble Pd(0) nanoparticles by E. coli, and investigates the biological mechanisms responsible for the bioreduction, and for the extracellular location of the nanoparticles.Previous work has been done at the Manchester Interdisciplinary Biocentre with the directed evolution of the monoamine oxidase enzyme of Aspergillus niger (known as MAO-N), which catalyses the oxidative deamination of terminal amines. The result has been to produce an enzyme with enhanced activity in the production of enantiomerically pure chiral amines. The modified enzyme catalyses the oxidation of the (S)-enantiomer to the corresponding imine, which is then reduced using a chemical reductant back to either the (S)- or the (R)-enantiomer, leading to an enantiomeric excess (e.e.) of the latter. After several cycles, enantiomerically pure amines are produced. In this study, E. coli transformed with a plasmid containing the variant mao-N-D5 gene insert demonstrated good activity in catalysing the oxidation of the (S)-enantiomer of the secondary amine 1-methyltetrahydroisoquinoline (MTQ) to the imine 1-methyldihydroisoquinoline (MDQ), as measured by HPLC. The ability of E. coli to reduce Pd(II) to Pd(0) was exploited in order to use the supported nanoparticles in place of the chemical reductant, catalysing the reduction of the imine back to MTQ. Following five cycles of oxidation and reduction, racemic MTQ was converted to (R)-MTQ with an enantiomeric excess of up to 93%. The activity of the biometallic catalyst immobilised in alginate beads was also assessed, and found to be the same as planktonic cells. The recyclability and long-term storage of the immobilised biocatalyst was also investigated, and it was found that freeze-drying maintained the stability of the beads for up to six weeks, which was the limit of the experiment.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Psychosocial impact of undergoing prostate cancer screening for men with BRCA1 or BRCA2 mutations.

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    OBJECTIVES: To report the baseline results of a longitudinal psychosocial study that forms part of the IMPACT study, a multi-national investigation of targeted prostate cancer (PCa) screening among men with a known pathogenic germline mutation in the BRCA1 or BRCA2 genes. PARTICPANTS AND METHODS: Men enrolled in the IMPACT study were invited to complete a questionnaire at collaborating sites prior to each annual screening visit. The questionnaire included sociodemographic characteristics and the following measures: the Hospital Anxiety and Depression Scale (HADS), Impact of Event Scale (IES), 36-item short-form health survey (SF-36), Memorial Anxiety Scale for Prostate Cancer, Cancer Worry Scale-Revised, risk perception and knowledge. The results of the baseline questionnaire are presented. RESULTS: A total of 432 men completed questionnaires: 98 and 160 had mutations in BRCA1 and BRCA2 genes, respectively, and 174 were controls (familial mutation negative). Participants' perception of PCa risk was influenced by genetic status. Knowledge levels were high and unrelated to genetic status. Mean scores for the HADS and SF-36 were within reported general population norms and mean IES scores were within normal range. IES mean intrusion and avoidance scores were significantly higher in BRCA1/BRCA2 carriers than in controls and were higher in men with increased PCa risk perception. At the multivariate level, risk perception contributed more significantly to variance in IES scores than genetic status. CONCLUSION: This is the first study to report the psychosocial profile of men with BRCA1/BRCA2 mutations undergoing PCa screening. No clinically concerning levels of general or cancer-specific distress or poor quality of life were detected in the cohort as a whole. A small subset of participants reported higher levels of distress, suggesting the need for healthcare professionals offering PCa screening to identify these risk factors and offer additional information and support to men seeking PCa screening

    The FANCM:p.Arg658* truncating variant is associated with risk of triple-negative breast cancer

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    Abstract: Breast cancer is a common disease partially caused by genetic risk factors. Germline pathogenic variants in DNA repair genes BRCA1, BRCA2, PALB2, ATM, and CHEK2 are associated with breast cancer risk. FANCM, which encodes for a DNA translocase, has been proposed as a breast cancer predisposition gene, with greater effects for the ER-negative and triple-negative breast cancer (TNBC) subtypes. We tested the three recurrent protein-truncating variants FANCM:p.Arg658*, p.Gln1701*, and p.Arg1931* for association with breast cancer risk in 67,112 cases, 53,766 controls, and 26,662 carriers of pathogenic variants of BRCA1 or BRCA2. These three variants were also studied functionally by measuring survival and chromosome fragility in FANCM−/− patient-derived immortalized fibroblasts treated with diepoxybutane or olaparib. We observed that FANCM:p.Arg658* was associated with increased risk of ER-negative disease and TNBC (OR = 2.44, P = 0.034 and OR = 3.79; P = 0.009, respectively). In a country-restricted analysis, we confirmed the associations detected for FANCM:p.Arg658* and found that also FANCM:p.Arg1931* was associated with ER-negative breast cancer risk (OR = 1.96; P = 0.006). The functional results indicated that all three variants were deleterious affecting cell survival and chromosome stability with FANCM:p.Arg658* causing more severe phenotypes. In conclusion, we confirmed that the two rare FANCM deleterious variants p.Arg658* and p.Arg1931* are risk factors for ER-negative and TNBC subtypes. Overall our data suggest that the effect of truncating variants on breast cancer risk may depend on their position in the gene. Cell sensitivity to olaparib exposure, identifies a possible therapeutic option to treat FANCM-associated tumors

    Henkilöstön vaihtuvuus ja siihen liittyvät tekijät telemarkkinointialalla : case: Gainer Oy

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    Tämä opinnäytetyö toteutettiin toimeksiantosopimuksena Gainer Oy:lle, joka on toiminut telemarkkinoinnin alalla jo vuodesta 1984. Opinnäytetyön tutkimusstrategiaksi valittiin case study eli tapaustutkimus. Käytimme tutkimusmenetelmänä kvalitatiivista eli laadullista tutkimusta. Tavoitteenamme oli tutkia ja selvittää henkilöstön vaihtuvuutta ja siihen liittyviä tekijöitä alalla, jossa henkilöstön vaihtuvuus koetaan ongelmaksi. Teoriaosuudessa käsittelemme teoreettisen viitekehyksen liittyen työnantajan keinoihin vaikuttaa työntekijän sitouttamiseen. Tämä on jaettu kahteen osa-alueeseen, jotka ovat rekrytointi sekä työhyvinvointi ja osaamisen kehittäminen. Empiirisessä osiossa päädyimme käyttämään puolistrukturoitua teemahaastattelua, joka toteutettiin suurimmaksi osaksi puhelimitse sekä muutama haastattelu tehtiin kasvotusten. Teemahaastattelu valikoitui parhaimmaksi menetelmäksi johtuen aiheen moniulotteisuudesta. Avoimella haastattelulla emme olisi välttämättä saaneet merkittävää tietoa samassa mittakaavassa kuin puolistrukturoidulla mallilla. Opinnäytetyön tuloksena päädyimme esittämään toimeksiantajalle muutamia kehitysehdotuksia. Haastatteluista johdetuilla päätelmillä saatettaisiin parantaa rekrytoinnin onnistumista, joka osaltaan parantaa kannattavuutta niin tuloksellisesti, kuin henkilöstön resurssejakin säästäen. Kehitysehdotuksia muodostui myös muihin osa-alueisiin liittyen. Näillä on myös vaikutusta henkilöstön yleiseen työhyvinvointiin ja työssä jaksamiseen.This thesis was carried out as a commission agreement for Gainer Oy, which has operated in the field of telemarketing since 1984. Our study was carried out as a case study using qualitative approach as our research method. Our objective was to study personnel turnover and matters relating to it in a field where personnel turnover is seen as a problem. In the theoretical section of the study we deal with the theoretical frame of reference related to the employer's means to influence employee engagement. This is divided into two sections that are recruiting, and occupational health and development of skills. In the empirical part of our study, we ended up using half-structured theme interviews, which were mainly carried out by telephone. A few interviews were carried out face-to-face. Theme interview was selected to be the best method because of the multidimensionality of the subject. By using open interviews, we would not necessarily have received as much significant information as by using the half-structured model. As a result of our study, we presented a few development proposals for our client/commissioner. The conclusions drawn from the interviews may lead to more successful recruiting, which in turn improves viability both in terms of productivity and by saving the resources of the personnel. There were also other development proposals concerning other areas. The results of the study may also help to improve the general well-being at work and coping with one’s workload

    Prospective evaluation of body size and breast cancer risk among BRCA1 and BRCA2 mutation carriers

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    BACKGROUND:Although evidence suggests that larger body size in early life confers lifelong protection from developing breast cancer, few studies have investigated the relationship between body size and breast cancer risk among BRCA mutation carriers. Therefore, we conducted a prospective evaluation of body size and the risk of breast cancer among BRCA mutation carriers. METHODS:Current height and body mass index (BMI) at age 18 were determined from baseline questionnaires. Current BMI and weight change since age 18 were calculated from updated biennial follow-up questionnaires. Cox proportional hazards models were used to estimate the hazard ratio (HR) and 95% confidence interval (CI). RESULTS:Among 3734 BRCA mutation carriers, there were 338 incident breast cancers over a mean follow-up of 5.5 years. There was no association between height, current BMI or weight change and breast cancer risk. Women with BMI at age 18 ≥22.1 kg/m2 had a decreased risk of developing post-menopausal breast cancer compared with women with a BMI at age 18 between 18.8 and 20.3 kg/m2 (HR 0.49; 95% CI 0.30-0.82; P = 0.006). BMI at age 18 was not associated with risk of pre-menopausal breast cancer. CONCLUSIONS:There was no observed association between height, current BMI and weight change and risk of breast cancer. The inverse relationship between greater BMI at age 18 and post-menopausal breast cancer further supports a role of early rather than current or adulthood exposures for BRCA-associated breast cancer development. Future studies with longer follow-up and additional measures of adiposity are necessary to confirm these findings

    Kuntayhtymien talous vuonna 1968

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    Suomen virallinen tilasto (SVT
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