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1.
J Chem Phys ; 153(12): 124711, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33003711

RESUMO

Improving the efficiency of photo-electrocatalytic cells depends on controlling the rates of interfacial electron transfer to promote the formation of long-lived charge separated states. Ultimately, for efficient catalytic assemblies to see widespread implementation, repeated electron transfer in the absence of charge recombination needs to be realized. In this study, a series of manganese-based transition metal complexes known to undergo charge transfer-induced spin crossover are employed to study how significant increases in inner-sphere reorganization energy affect the rates of interfacial electron transfer. Each complex is characterized by transient spectroscopic and electrochemical methods to calculate the rate of electron transfer to a model chromophore anchored to the surface of a TiO2 film. Likewise, open-circuit voltage decay measurements were used to determine the voltage-dependent lifetime of injected electrons in TiO2 in the presence of each complex. To further characterize the rates of electronic recombination, density functional theory was used to calculate the inner-sphere and outer-sphere reorganization energy for each complex. These calculations were then combined with classical Marcus theory to determine the theoretical rate of back-electron transfer from the TiO2 conduction band. These results show that, in model complexes, a significant reduction in the recombination rate constant is achieved for complexes possessing a significant inner-sphere reorganization energy.

2.
Community Dent Health ; 37(2): 161-166, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32227704

RESUMO

OBJECTIVE: To describe the shape of the relationship between area deprivation and dental attendance (DA) in children aged 5 years and under in England and the modifying effect of caries prevalence, ethnicity, family profile and dentist-to-population ratio. BASIC RESEARCH DESIGN: DA rates were calculated at lower-tier local authority level (LA, n=326) using NHS data for the year to March 2017. LA deprivation was determined by Index of Multiple Deprivation 2015. Caries prevalence was retrieved from the 2016/17 National Dental Epidemiology Programme; ethnicity and family profile from Census 2011 and dentist-to-population ratio from NHS statistics. Fractional polynomial (FP) models explored the shape of the relationship. Multivariable regression models were adjusted for covariates. The effect of moderators was estimated by adjusted marginal effects. CLINICAL SETTING: English Lower-tier LAs. MAIN OUTCOME MEASURE: Shape of the relationship between DA and deprivation and its moderators. RESULTS: Best-fitting second-order FP model (p=0.582) did not provide a better fit for the relationship than the linear model. Therefore, the linear model was selected for final analysis. Deprivation was associated with decreased DA rates (Coefficient=-0.39, 95%CI=-0.53,-0.24; p=⟨0.001); while White ethnicity (Coefficient=0.35, 95%CI=0.29, 0.41; p=⟨0.001), single parenthood (Coefficient = 2.21, 95%CI=0.91,3.51; p=0.001) and caries prevalence (Coefficient =0.34, 95%CI=0.25,0.44; p=⟨0.001) with increased rates. These moderated the relationship. CONCLUSIONS: We hypothesised that the shape of the relationship between deprivation and DA could be curvilinear with higher rates in the extreme ends of deprivation. However, the analysis showed a linear association, moderated by the effect of ethnicity, single parenthood and disease level.


Assuntos
Cárie Dentária , Criança , Pré-Escolar , Inglaterra , Etnicidade , Família , Humanos , Prevalência
3.
Community Dent Health ; 36(3): 198-202, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31436922

RESUMO

OBJECTIVE: To investigate inequalities in three aspects of access to orthodontic care: uptake of orthodontic treatment, normative need and subjective need in England. METHODS: We used data from two surveys in England: 12 and 15-year-olds from the 2013 Child Dental Health Survey (CDHS 2013) and 12-year-olds from the 2008/2009 NHS Dental Epidemiology Programme for England (NDEP 2008/2009). Summary variables representing orthodontic status were calculated. Two regression-based summary measures of inequalities were used to investigate the relationship between deprivation level and orthodontic outcomes: Slope and Relative indices of Inequality. RESULTS: There were significant absolute and relative inequalities in uptake of orthodontic treatment. The least deprived were 1.9 times more likely to have received orthodontic treatment compared to the most deprived in both surveys. Normative need was not associated with deprivation in either the analyses of CDHS 2013 (SII= 0.03, 95% CI: -0.04, 0.1; RII=1.06, 95% CI: 0.91, 1.24) or the NDEP 2007/2008 (SII= 0.03, 95% CI: -0.02, 0.07; RII=1.06, 95% CI: 0.96, 1.18). There was greater willingness to have teeth straightened in more deprived children from CDHS 2013 (SII=-0.09, 95% CI: -0.16, -0.03; RII=0.85, 95% CI: 0.75, 0.96) but not in NDEP 2007/2008 (SII=0.03, 95% CI: 0, 0.06; RII=1.07, 95% CI: 0.99, 1.15). CONCLUSIONS: Being deprived was associated with lower uptake of orthodontic treatment. Normative need was not related to deprivation. The association between deprivation and subjective need was only partly established, with poorer children showing a greater desire to have their teeth straightened in one survey.


Assuntos
Assistência Odontológica , Inquéritos de Saúde Bucal , Disparidades em Assistência à Saúde , Ortodontia , Adolescente , Criança , Inglaterra , Humanos , Fatores Socioeconômicos , Inquéritos e Questionários
4.
Community Dent Health ; 36(1): 17-21, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30667186

RESUMO

OBJECTIVES: Oral health related quality of life (OHRQoL) has been linked to malocclusion. We aimed (a) to investigate the association between malocclusion and OHRQoL among children, and (b) to examine whether this association varied by socioeconomic status. METHODS: Cross-sectional analysis of data for 4,217 children aged 12 & 15 years, who participated in the 2013 Children Dental Health Survey (CDHS); a nationally representative survey of children in England, Wales, and Northern Ireland. Malocclusion was determined using the modified Index of Orthodontic Treatment Need (IOTN). OHRQoL was measured using the Child Oral Impacts on Daily Performance (Child-OIDP). For socioeconomic status, we used the pupils' eligibility for free school meals (FSM) and Index of Multiple Deprivation (IMD). Adjusted marginal effects were estimated controlling for confounding variables. Separate analyses were carried out for the two age groups. RESULTS: Malocclusion was associated with 6% and 15% increases in the probability of reporting negative impact of OHRQoL for 12- and 15-year olds respectively, which was significant for 15-year olds (marginal effect=0.15, 95% CI=0.08-0.22). Malocclusion was associated with the prevalence of oral impacts for 12 year olds (marginal effect=0.1, 95% CI=0.02-0.17) and 15-year olds (marginal effect=0.2, 95% CI 95%=0.13-0.28) not eligible for FSM and for 15-year olds in the most (marginal effect=0.2, 95% CI=0.1-0.29) and least (marginal effect=0.26, 95% CI=0.13-0.4) deprived IMD quintiles. CONCLUSIONS: Malocclusion was associated with impacts on OHRQoL for 15-year olds. There was evidence of a relationship between SES, malocclusion and OHRQoL.


Assuntos
Má Oclusão , Saúde Bucal , Qualidade de Vida , Adolescente , Criança , Estudos Transversais , Inglaterra , Humanos , Irlanda do Norte , Fatores Socioeconômicos , Inquéritos e Questionários , País de Gales
5.
Community Dent Health ; 36(1): 22-26, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30779499

RESUMO

OBJECTIVE: To describe child dental attendance (DA) by 1 year of age in England and its relationship with area deprivation. BASIC RESEARCH DESIGN: Analysis of National Health Service data for the 12 months to June 2017. Deprivation was measured by Index of Multiple Deprivation Rank of Average Score (2015) for upper-tier and unitary local authorities in England (LAs, n=151). DA rates were calculated for children under 1 year (⟨1yr) and children aged 1 year and under (⟨1yr). A Spearman's test assessed strength of association with deprivation. The Slope Index of Inequality (SII) and Relative Index of Inequality (RII) explored equity. CLINICAL SETTING: Upper-tier and unitary LAs in England. MAIN OUTCOME MEASURE: Attending an NHS primary care dental service. RESULTS: DA rates ranged from 0 to 12.3% (Median:2; IQR:1.4,3.9) in children ⟨1yr and from 3.7 to 37.6% (Median:10; IQR:7.4,17) in children ≤1yr. DA rates decreased as deprivation decreased (Spearman=-0.25, p=0.0019 in children ⟨1yr; Spearman=-0.21, p=0.0104 in children ≤1yr). The SII suggested a 2 percentage point difference in DA rate across the deprivation distribution in children ⟨1yr (SII=-0.02, 95% CI=-0.01,-0.04; p=⟨0.001); and a 5 point difference in children ≤1yr (SII=-0.05, 95% CI=-0.02,-0.09; p=0.003). The DA rate in the most deprived LA was 2.1 higher than the least deprived LA (RII=2.1, 95% CI=1.4,3.2; p=⟨0.001) in children ⟨1yr and 1.5 higher (RII=1.5, 95% CI=1.2,2; p=0.004) in children ≤1yr. CONCLUSIONS: DA rates were low for all LAs and only partially explained by deprivation. More deprived LAs were, unexpectedly, more likely to report higher DA rates.


Assuntos
Assistência Odontológica , Governo Local , Atenção Primária à Saúde , Criança , Inglaterra , Disparidades nos Níveis de Saúde , Humanos , Lactente , Fatores Socioeconômicos
6.
Antimicrob Agents Chemother ; 59(11): 6725-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26282428

RESUMO

Neither breakpoints (BPs) nor epidemiological cutoff values (ECVs) have been established for Candida spp. with anidulafungin, caspofungin, and micafungin when using the Sensititre YeastOne (SYO) broth dilution colorimetric method. In addition, reference caspofungin MICs have so far proven to be unreliable. Candida species wild-type (WT) MIC distributions (for microorganisms in a species/drug combination with no detectable phenotypic resistance) were established for 6,007 Candida albicans, 186 C. dubliniensis, 3,188 C. glabrata complex, 119 C. guilliermondii, 493 C. krusei, 205 C. lusitaniae, 3,136 C. parapsilosis complex, and 1,016 C. tropicalis isolates. SYO MIC data gathered from 38 laboratories in Australia, Canada, Europe, Mexico, New Zealand, South Africa, and the United States were pooled to statistically define SYO ECVs. ECVs for anidulafungin, caspofungin, and micafungin encompassing ≥97.5% of the statistically modeled population were, respectively, 0.12, 0.25, and 0.06 µg/ml for C. albicans, 0.12, 0.25, and 0.03 µg/ml for C. glabrata complex, 4, 2, and 4 µg/ml for C. parapsilosis complex, 0.5, 0.25, and 0.06 µg/ml for C. tropicalis, 0.25, 1, and 0.25 µg/ml for C. krusei, 0.25, 1, and 0.12 µg/ml for C. lusitaniae, 4, 2, and 2 µg/ml for C. guilliermondii, and 0.25, 0.25, and 0.12 µg/ml for C. dubliniensis. Species-specific SYO ECVs for anidulafungin, caspofungin, and micafungin correctly classified 72 (88.9%), 74 (91.4%), 76 (93.8%), respectively, of 81 Candida isolates with identified fks mutations. SYO ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin, micafungin, and especially caspofungin, since testing the susceptibilities of Candida spp. to caspofungin by reference methodologies is not recommended.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Equinocandinas/farmacologia , Lipopeptídeos/farmacologia , Anidulafungina , Candida/genética , Caspofungina , Micafungina , Testes de Sensibilidade Microbiana , Mutação/genética
7.
Biochim Biophys Acta ; 1831(1): 126-32, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22835522

RESUMO

Lipid phosphate phosphatases (LPP) are integral membrane proteins with broad substrate specificity that dephosphorylate lipid substrates including phosphatidic acid, lysophosphatidic acid, ceramide 1-phosphate, sphingosine 1-phosphate, and diacylglycerol pyrophosphate. Although the three mammalian enzymes (LPP1-3) demonstrate overlapping catalytic activities and substrate preferences in vitro, the phenotypes of mice with targeted inactivation of the Ppap2 genes encoding the LPP enzymes reveal nonredundant functions. A specific role for LPP3 in vascular development has emerged from studies of mice lacking Ppap2b. A meta-analysis of multiple, large genome-wide association studies identified a single nucleotide polymorphism in PPAP2B as a novel predictor of coronary artery disease. In this review, we will discuss the evidence that links LPP3 to vascular development and disease and evaluate potential molecular mechanisms. This article is part of a Special Issue entitled Advances in Lysophospholipid Research.


Assuntos
Vasos Sanguíneos/enzimologia , Vasos Sanguíneos/crescimento & desenvolvimento , Fosfatidato Fosfatase/metabolismo , Animais , Doenças Cardiovasculares/enzimologia , Doenças Cardiovasculares/patologia , Humanos , Lisofosfolipídeos/metabolismo , Fosfatidato Fosfatase/química , Receptores de Lisoesfingolipídeo/metabolismo , Transdução de Sinais
8.
J Hepatol ; 60(2): 457-60, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24140803

RESUMO

Hemospray is a haemostatic agent licensed for endoscopic haemostasis of non-variceal upper gastrointestinal bleeding (NVUGIB) in Europe and Canada. Hemospray has been shown to be safe and effective in achieving haemostasis in bleeding peptic ulcers in a prospective clinical study and several further case series have described the use of hemospray in other non-variceal causes of gastrointestinal bleeding. Portal hypertensive gastropathy and colopathy are common in patients with portal hypertension. As hemospray is an easy to apply, non-contact method, which can cover large areas of mucosa, it may be of benefit in acute non-variceal portal hypertensive bleeding. We present data from the first four consecutive patients presenting to our institution with acute haemorrhage secondary to non-variceal diffuse portal hypertensive bleeding treated with hemospray.


Assuntos
Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Hemostáticos/administração & dosagem , Hipertensão Portal/complicações , Minerais/administração & dosagem , Idoso , Feminino , Hemostase Endoscópica/métodos , Humanos , Cirrose Hepática/complicações , Masculino , Pós/administração & dosagem
9.
J Dent Res ; 102(1): 5-12, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36081351

RESUMO

The poor physical health (including oral health) of people with mental disorders is a global problem. The burden of oral diseases among this group is substantial given their high prevalence and ability to increase the personal, social, and economic impacts of mental disorders. This article summarizes causes of mental disorders and oral diseases, critically reviews current evidence on interventions to reduce the burden of oral diseases in people with mental disorders, and suggests future research directions. The relationship between mental disorders and oral diseases is complex due to the shared social determinants and bidirectional interaction mechanisms that involve interconnected social, psychological, behavioral, and biological processes. Research has, to date, failed to produce effective and scalable interventions to tackle the burden of oral diseases among people with mental disorders. Transformative research and actions informed by a dynamic involvement of biological, behavioral, and social sciences are needed to understand and tackle the complex relationship between mental disorders and oral diseases, as well as inform the design of complex interventions. Examples of future research on complex public health, health service, and social care interventions are provided. The design and testing of these interventions should be carried out in real-world settings, underpinned by the principles of coproduction and systems thinking, and conducted by a transdisciplinary team. We propose this starts with setting research priorities and developing complex intervention theory, which we report to support future research to improve oral health and hence physical and mental health in this disadvantaged group.


Assuntos
Transtornos Mentais , Doenças da Boca , Humanos , Transtornos Mentais/complicações , Doenças da Boca/complicações
10.
J Hosp Infect ; 131: 164-172, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36270518

RESUMO

BACKGROUND: There are no contemporary data on healthcare-associated infections (HAIs) in New Zealand. AIMS: To determine the epidemiology of HAIs, prevalence of medical devices, and microbiology of HAIs in adults in public hospitals in New Zealand. METHODS: Point prevalence survey. Surveyors reviewed patients aged ≥18 years using the HAI definitions of the European Centres for Disease Prevention and Control. Device use and microbiology of HAIs were recorded. FINDINGS: In total, 5468 patients were surveyed; 361 patients (6.6%) had 423 HAIs (7.7 HAIs per 100 patients). The most common HAIs were: surgical site infections (N=104, 25%), urinary tract infections (N=80, 19%), pneumonia (N=75, 18%) and bloodstream infections (N=55, 13%). Overall, 3585 patients (66%) had at least one device, with 2922 (53%) patients having a peripheral intravenous catheter. Sixty-nine (16%) HAIs were device-associated. On multi-variable analysis, independent risk factors for HAIs included the presence of a peripheral [odds ratio (OR) 2.0] or central (OR 5.7) intravenous catheter and clinical service. HAI rates were higher in surgical patients (OR 1.8), intensive care unit patients (OR 2.6) and rehabilitation/older persons' health patients (OR 2.4) compared with general medicine patients (P≤0.01 for all groups). In total, 301 organisms were identified. Clostridioides difficile infection was uncommon, accounting for 1.7% of all HAIs. Forty-two isolates (14%) were drug-resistant, and most (N=33, 79%) were Enterobacterales. CONCLUSION: This study established the most common HAIs and their risk factors in New Zealand. The high prevalence of device use underscores the need to ensure that proven multi-modal prevention interventions are in place. However, as less than half of HAIs are device- or surgery-associated, other intervention strategies will be required to reduce their burden.


Assuntos
Infecções por Clostridium , Infecção Hospitalar , Infecções Urinárias , Adulto , Humanos , Adolescente , Idoso , Idoso de 80 Anos ou mais , Prevalência , Nova Zelândia/epidemiologia , Infecção Hospitalar/microbiologia , Hospitais Públicos , Infecções Urinárias/epidemiologia
11.
Community Dent Health ; 29(3): 252-6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23038945

RESUMO

AIM: The aim of this study was to consider reported working patterns of dentists and retention of the dental workforce. METHOD: Three cohorts of dental graduates from the University of Birmingham (n = 505) were tracked using the General Dental Council (GDC) register to assess retention of the workforce. A questionnaire was sent to these graduates to explore changes in working patterns over time and to investigate the factors which had influenced their choice of job location. RESULTS: A high proportion (90.9%) of the dental graduates included in this tracking exercise were found on the GDC register on the census date. A slightly higher proportion of female graduates (10.3%) than male graduates (8.0%) could not be traced on the current register (p = 0.37). A change in working patterns over time was demonstrated, with more general dental practitioners reporting a shorter working week. 'Availability of jobs' was the factor reported by most respondents to be important in determining job location. CONCLUSION: This study provides evidence of changing work patterns over time. Furthermore, although the majority of the study sample remained on the GDC register, there appeared to have been a gradual loss of subjects from the dental workforce over time. Changes such as these may affect the provision of services and the impact of investment in training. Further research in this area is warranted.


Assuntos
Mobilidade Ocupacional , Faculdades de Odontologia , Estudos de Coortes , Feminino , Humanos , Masculino , Reino Unido
12.
Scott Med J ; 55(3): 4-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20795508

RESUMO

BACKGROUND AND AIMS: Whilst hepatitis B (HBV) is historically uncommon in Scotland, anecdotal experience suggests an increasing prevalence of chronic infection. We sought to establish whether the incidence of chronic HBV is increasing in Greater Glasgow, and whether patients are assessed in secondary care. METHODS: The regional virus centre database identified HBV surface antigen (HBsAg) positive samples. For adult patients tested in Glasgow between 1993-2007 the first positive test was identified and classified as acute or chronic infection serologically. Clinic referral and attendance data was then obtained. RESULTS: 1,672 patients tested HBsAg positive; 1051 with chronic infection, 421 acute and 200 indeterminate. New diagnoses of HBV remained stable over time, however falling numbers of acute cases were mirrored by a rise in chronic cases from 40 to 119 per annum between 2000 and 2007. Of 193 patients diagnosed in 2006 and 2007, 51% were not seen in secondary care due to non referral (43%) or non attendance (8%). CONCLUSION: Chronic HBV trebled in Glasgow between 2000 and 2007. Most patients were not assessed in secondary care. Improved levels of clinic referral and attendance are required to ensure best care for HBV patients in Glasgow.


Assuntos
Hepatite B/epidemiologia , Doença Aguda , Hepatite B Crônica/epidemiologia , Humanos , Incidência , Escócia/epidemiologia
13.
JDR Clin Trans Res ; 5(2): 185-194, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31487468

RESUMO

INTRODUCTION: Despite a decline in the prevalence of dental caries among children in England and ongoing arrangements for the provision of free dental care up to the age of 18 y, there is limited information on the pattern and trend of socioeconomic inequalities in dental caries and dental attendance. METHODS: We estimated the magnitude of deprivation-related inequalities for dental caries and dental attendance in young children, using publicly available data and 2 regression-based summary measures of inequalities: slope index of inequality and relative index of inequality. RESULTS: We found no significant absolute or relative inequalities in dental attendance across English areas in the past decade, while there were persistent absolute and relative inequalities in dental caries. Socioeconomic inequalities in dental caries decreased between 2007 and 2012; thereafter, the relative inequalities increased. CONCLUSIONS: The apparent widening inequality in child dental caries in England despite equal access to dental care is a challenge for policy makers. KNOWLEDGE TRANSFER STATEMENT: While caries prevalence among English children has declined over the past decade, there has been an increase in socioeconomic inequalities in oral health despite there being no inequality in dental attendance. This has implications for the development of oral health strategy and planning dental services.


Assuntos
Cárie Dentária , Criança , Pré-Escolar , Inglaterra , Disparidades nos Níveis de Saúde , Humanos , Saúde Bucal , Fatores Socioeconômicos
14.
J Cell Biol ; 140(1): 81-90, 1998 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-9425156

RESUMO

Phospholipase D (PLD) enzymes catalyze the hydrolysis of phosphatidylcholine and are involved in membrane trafficking and cytoskeletal reorganization. The Saccharomyces cerevisiae SPO14 gene encodes a PLD that is essential for meiosis. We have analyzed the role of PLD in meiosis by examining two mutant proteins, one with a point mutation in a conserved residue (Spo14pK--> H) and one with an amino-terminal deletion (Spo14pDeltaN), neither of which can restore meiosis in a spo14 deletion strain. Spo14pK--> H is enzymatically inactive, indicating that PLD activity is required, whereas Spo14pDeltaN retains PLD catalytic activity in vitro, indicating that PLD activity is not sufficient for meiosis. To explore other aspects of Spo14 function, we followed the localization of the enzyme during meiosis. Spo14p is initially distributed throughout the cell, becomes concentrated at the spindle pole bodies after the meiosis I division, and at meiosis II localizes to the new spore membrane as it surrounds the nuclei and then expands to encapsulate the associated cytoplasm during the formation of spores. The catalytically inactive protein also undergoes relocalization during meiosis; however, in the absence of PLD activity, no membrane is formed. In contrast, Spo14pDeltaN does not relocalize properly, indicating that the failure of this protein to complement a spo14 mutant is due to its inability to localize its PLD activity. Furthermore, we find that Spo14p movement is correlated with phosphorylation of the protein. These experiments indicate that PLD participates in regulated membrane formation during meiosis, and that both its catalytic activity and subcellular redistribution are essential for this function.


Assuntos
Membrana Celular/fisiologia , Fosfolipase D/metabolismo , Saccharomyces cerevisiae/fisiologia , Fosfatase Alcalina , Animais , Membrana Celular/ultraestrutura , Citosol/fisiologia , Decápodes , Genes Fúngicos , Genótipo , Meiose , Fosfatos/metabolismo , Fosfolipase D/genética , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Esporos Fúngicos/fisiologia , Esporos Fúngicos/ultraestrutura
15.
J Cell Biol ; 138(3): 495-504, 1997 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-9245781

RESUMO

Phospholipase D (PLD) is a phospholipid hydrolyzing enzyme whose activation has been implicated in mediating signal transduction pathways, cell growth, and membrane trafficking in mammalian cells. Several laboratories have demonstrated that small GTP-binding proteins including ADP-ribosylation factor (ARF) can stimulate PLD activity in vitro and an ARF-activated PLD activity has been found in Golgi membranes. Since ARF-1 has also been shown to enhance release of nascent secretory vesicles from the TGN of endocrine cells, we hypothesized that this reaction occurred via PLD activation. Using a permeabilized cell system derived from growth hormone and prolactin-secreting pituitary GH3 cells, we demonstrate that immunoaffinity-purified human PLD1 stimulated nascent secretory vesicle budding from the TGN approximately twofold. In contrast, a similarly purified but enzymatically inactive mutant form of PLD1, designated Lys898Arg, had no effect on vesicle budding when added to the permeabilized cells. The release of nascent secretory vesicles from the TGN was sensitive to 1% 1-butanol, a concentration that inhibited PLD-catalyzed formation of phosphatidic acid. Furthermore, ARF-1 stimulated endogenous PLD activity in Golgi membranes approximately threefold and this activation correlated with its enhancement of vesicle budding. Our results suggest that ARF regulation of PLD activity plays an important role in the release of nascent secretory vesicles from the TGN.


Assuntos
Grânulos Citoplasmáticos/metabolismo , Glicerofosfolipídeos , Complexo de Golgi/metabolismo , Fosfolipase D/metabolismo , 1-Butanol , Fatores de Ribosilação do ADP , Animais , Butanóis/farmacologia , Linhagem Celular , Ativação Enzimática , Proteínas de Ligação ao GTP/fisiologia , Humanos , Ácidos Fosfatídicos/metabolismo , Fosfolipase D/farmacologia , Fosfolipídeos/metabolismo , Hipófise , Plantas/enzimologia , Ratos
16.
Community Dent Health ; 26(3): 170-6, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19780358

RESUMO

AIMS: The aim of the study was to investigate the reported working patterns, dentist perceptions and patient oral health for dentists in a Personal Dental Services (PDS) pilot and compare this with that of matched dentists working in the General Dental Services (GDS) arrangements in the same part of England. METHOD: Ten dentists were recruited, five each from PDS and GDS practices in Warwickshire, UK. The number of interventions carried out for adult patients in the year to April 2003 was obtained from the Dental Practice Board (DPB) for the two groups and compared. An Oral Health Index (OHX) (Burke and Wilson, 1995) was used to determine the oral health of a selection of patients from the two groups of dentists in the study. The final stage of the study involved semi-structured interviews with the dentists. RESULTS: The average age of dentists was similar, in the early to mid 40's (p>0.05). Both groups were, on average, around 20 years post qualification. The GDS dentists made an average of 3,507 activity reports to the Dental Practice Board in the year examined, compared with 3,441 from the PDS dentists. PDS dentists provided fewer simple periodontal treatments than GDS dentists, but otherwise the pattern of reported activity was similar. Both PDS and GDS dentists suggested that GDS dentists carried out more fillings because of a perverse incentive to provide fillings compared with PDS arrangements. PDS dentists believed that their treatment profiles had not changed significantly since changing to PDS, and suggested that their prescribing was based on clinical need only and was not influenced by the remuneration system. A total of 225 OHX scores were obtained for patients attending PDS dentists and a further 214 from patients attending GDS dentists. Overall, the mean OHX score was lower in the GDS patients than for PDS patients. CONCLUSIONS: PDS dentists provided fewer simple periodontal treatments than their GDS counterparts. There was no difference in the oral health of patients treated under either system. Although there was some evidence of a difference in attitude between GDS and PDS dentists towards charging and claiming for simple periodontal treatment, there was no uniformity of opinion within either group. There would appear to be a number of complex factors impacting upon decisions to treat or monitor dental conditions.


Assuntos
Serviços de Saúde Bucal/estatística & dados numéricos , Odontologia Geral/estatística & dados numéricos , Avaliação de Processos e Resultados em Cuidados de Saúde , Assistência Individualizada de Saúde/estatística & dados numéricos , Padrões de Prática Odontológica/estatística & dados numéricos , Adulto , Atitude do Pessoal de Saúde , Serviços de Saúde Bucal/organização & administração , Odontólogos/psicologia , Feminino , Odontologia Geral/organização & administração , Humanos , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Programas Nacionais de Saúde/organização & administração , Programas Nacionais de Saúde/estatística & dados numéricos , Assistência Individualizada de Saúde/organização & administração , Projetos Piloto , Mecanismo de Reembolso , Medicina Estatal , Reino Unido
17.
Sci Adv ; 5(4): eaav9044, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30972369

RESUMO

Hypergolic materials, capable of spontaneous ignition upon contact with an external oxidizer, are of critical importance as fuels and propellants in aerospace applications (e.g., rockets and spacecraft). Currently used hypergolic fuels are highly energetic, toxic, and carcinogenic hydrazine derivatives, inspiring the search for cleaner and safer hypergols. Here, we demonstrate the first strategy to design hypergolic behavior within a metal-organic framework (MOF) platform, by using simple "trigger" functionalities to unlock the latent and generally not recognized energetic properties of zeolitic imidazolate frameworks, a popular class of MOFs. The herein presented six hypergolic MOFs, based on zinc, cobalt, and cadmium, illustrate a uniquely modular platform to develop hypergols free of highly energetic or carcinogenic components, in which varying the metal and linker components enables the modulation of ignition and combustion properties, resulting in excellent hypergolic response evident by ultrashort ignition delays as low as 2 ms.

19.
J Hosp Infect ; 68(4): 355-62, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18353497

RESUMO

We aimed to document the epidemiology of extended-spectrum beta-lactamase (ESBL)-producing enterobacteria in the Auckland community and identify factors associated with infection using a case-control study design. ESBL-producing enterobacteria were isolated from 107 infected patients, for which demographic and clinical data were available for 98 cases (92%). Escherichia coli was the predominant organism (82%), with urine as the commonest source (97%). Compared with a control group infected with ESBL-negative enterobacteria, factors significantly associated with infection on univariate analysis were: living in a residential care home (RCH); recent admission to hospital 'M'; recent antibiotic use; older age (>75 years); presence of a urinary catheter; and a history of comorbid chronic obstructive pulmonary disease (COPD), cardiovascular disease, neurological disease or recurrent urinary tract infection. On multivariate analysis, residence in RCH and COPD remained significant associations. Pulsed-field gel electrophoresis typing of the ESBL-producing E. coli identified a common strain. We concluded that residence in RCH and a history of COPD are significant associations with ESBL-producing enterobacterial infection in the Auckland community. Several spatial clusters in RCHs and a common strain suggest point-source outbreaks. A substantial number of community cases did not live in an RCH nor had been recently hospitalised, suggesting the independent generation of ESBL-producing enterobacteria in the broader community.


Assuntos
Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/isolamento & purificação , beta-Lactamases/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Comorbidade , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Eletroforese em Gel de Campo Pulsado , Enterobacteriaceae/enzimologia , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/isolamento & purificação , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Instituições Residenciais , Fatores de Risco , Inquéritos e Questionários , Urina/microbiologia
20.
Gut ; 56(12): 1743-6, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17627961

RESUMO

INTRODUCTION: There is no consensus on the pharmacological treatment of alcoholic hepatitis. The Glasgow alcoholic hepatitis score (GAHS) has been shown to be more accurate than the modified Maddrey's discriminant function (mDF) in the prediction of outcome from alcoholic hepatitis. This study aimed to determine whether the GAHS was able to identify those patients who would benefit from corticosteroids. METHODS: 225 patients with an mDF greater than or equal to 32 from five hospital centres in the United Kingdom were reviewed. Patient survival relative to the GAHS and the use of corticosteroids was recorded. RESULTS: 144 patients with an mDF greater than or equal to 32 (64%) also had a GAHS greater than or equal to 9. There was no difference in survival between untreated or corticosteroid-treated patients for those with a GAHS less than 9. For patients with a GAHS greater than or equal to 9 the 28-day survival for untreated and corticosteroid-treated patients was 52% and 78% (p = 0.002), and 84-day survival was 38% and 59% (p = 0.02), respectively. CONCLUSIONS: Among patients with an mDF greater than or equal to 32, there was no appreciable benefit from treatment with corticosteroids in patients with a GAHS less than 9. Patients with a GAHS greater than or equal to 9 have an extremely poor prognosis if they are not treated with corticosteroids, or if such treatment is contraindicated.


Assuntos
Glucocorticoides/uso terapêutico , Hepatite Alcoólica/diagnóstico , Hepatite Alcoólica/tratamento farmacológico , Seleção de Pacientes , Índice de Gravidade de Doença , Adulto , Humanos , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida , Resultado do Tratamento
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