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1.
Diabet Med ; : e15370, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837551

RESUMO

AIMS: To explore UK healthcare professionals' practice and attitudes towards asking women with diabetes about sexual health problems, including symptoms of female sexual dysfunction (FSD). METHODS: An online questionnaire to address the study aims was developed, piloted by ten healthcare professionals (HCPs) and completed by 111 eligible HCPs, recruited via professional networks and social media. Free text data were analysed and reported thematically. Two questions were analysed to test the hypothesis of differences between men's and women's responses. RESULTS: The majority of respondents did not ask women with diabetes about sexual problems. Multiple barriers to inquiry were reported, including inadequate training, time constraints, competing priorities, the perceived likelihood that questions will cause surprise or distress (especially for certain groups of women), the belief that sexual problems are to be expected as women age, and the belief that FSD is complex or untreatable, with unclear management pathways. Exploratory findings indicated significant differences in men and women's responses (men disagreed more strongly with prioritisation, and fewer reported routine inquiry about sexual problems in their usual practice). CONCLUSIONS: HCPs reported not asking women with diabetes about sexual problems during routine care. They described multiple factors reinforcing the silence about sexual health, including inadequate education and perceived social risk for individual HCPs who deviate from the patterns of topics usually discussed in diabetes consultations.

2.
PLoS Biol ; 17(5): e3000258, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31136566

RESUMO

AccessLabs are workshops with two simultaneous motivations, achieved through direct citizen-scientist pairings: (1) to decentralise research skills so that a broader range of people are able to access/use scientific research, and (2) to expose science researchers to the difficulties of using their research as an outsider, creating new open access advocates. Five trial AccessLabs have taken place for policy makers, media/journalists, marine sector participants, community groups, and artists. The act of pairing science academics with local community members helps build understanding and trust between groups at a time when this relationship appears to be under increasing threat from different political and economic currents in society. Here, we outline the workshop motivations, format, and evaluation, with the aim that others can build on the methods developed.


Assuntos
Congressos como Assunto , Pesquisa , Ciência , Pesquisadores
3.
N Engl J Med ; 379(14): 1322-1331, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30281988

RESUMO

BACKGROUND: Candida auris is an emerging and multidrug-resistant pathogen. Here we report the epidemiology of a hospital outbreak of C. auris colonization and infection. METHODS: After identification of a cluster of C. auris infections in the neurosciences intensive care unit (ICU) of the Oxford University Hospitals, United Kingdom, we instituted an intensive patient and environmental screening program and package of interventions. Multivariable logistic regression was used to identify predictors of C. auris colonization and infection. Isolates from patients and from the environment were analyzed by whole-genome sequencing. RESULTS: A total of 70 patients were identified as being colonized or infected with C. auris between February 2, 2015, and August 31, 2017; of these patients, 66 (94%) had been admitted to the neurosciences ICU before diagnosis. Invasive C. auris infections developed in 7 patients. When length of stay in the neurosciences ICU and patient vital signs and laboratory results were controlled for, the predictors of C. auris colonization or infection included the use of reusable skin-surface axillary temperature probes (multivariable odds ratio, 6.80; 95% confidence interval [CI], 2.96 to 15.63; P<0.001) and systemic fluconazole exposure (multivariable odds ratio, 10.34; 95% CI, 1.64 to 65.18; P=0.01). C. auris was rarely detected in the general environment. However, it was detected in isolates from reusable equipment, including multiple axillary skin-surface temperature probes. Despite a bundle of infection-control interventions, the incidence of new cases was reduced only after removal of the temperature probes. All outbreak sequences formed a single genetic cluster within the C. auris South African clade. The sequenced isolates from reusable equipment were genetically related to isolates from the patients. CONCLUSIONS: The transmission of C. auris in this hospital outbreak was found to be linked to reusable axillary temperature probes, indicating that this emerging pathogen can persist in the environment and be transmitted in health care settings. (Funded by the National Institute for Health Research Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance at Oxford University and others.).


Assuntos
Candida , Candidíase/epidemiologia , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Contaminação de Equipamentos , Reutilização de Equipamento , Controle de Infecções/métodos , Unidades de Terapia Intensiva , Termômetros/microbiologia , Adulto , Candida/genética , Candida/isolamento & purificação , Candidíase/mortalidade , Candidíase/transmissão , Estudos de Casos e Controles , Infecção Hospitalar/mortalidade , Infecção Hospitalar/transmissão , Feminino , Departamentos Hospitalares , Humanos , Incidência , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Análise Multivariada , Neurologia , Filogenia , Fatores de Risco , Reino Unido/epidemiologia
4.
Proc Biol Sci ; 288(1942): 20202823, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33434457

RESUMO

The motion dazzle hypothesis posits that high contrast geometric patterns can cause difficulties in tracking a moving target and has been argued to explain the patterning of animals such as zebras. Research to date has only tested a small number of patterns, offering equivocal support for the hypothesis. Here, we take a genetic programming approach to allow patterns to evolve based on their fitness (time taken to capture) and thus find the optimal strategy for providing protection when moving. Our 'Dazzle Bug' citizen science game tested over 1.5 million targets in a touch screen game at a popular visitor attraction. Surprisingly, we found that targets lost pattern elements during evolution and became closely background matching. Modelling results suggested that targets with lower motion energy were harder to catch. Our results indicate that low contrast, featureless targets offer the greatest protection against capture when in motion, challenging the motion dazzle hypothesis.


Assuntos
Ciência do Cidadão , Percepção de Movimento , Animais , Movimento (Física) , Movimento
5.
Artigo em Inglês | MEDLINE | ID: mdl-32205351

RESUMO

Resistance to amoxicillin-clavulanate, a widely used beta-lactam/beta-lactamase inhibitor combination antibiotic, is rising globally, and yet susceptibility testing remains challenging. To test whether whole-genome sequencing (WGS) could provide a more reliable assessment of susceptibility than traditional methods, we predicted resistance from WGS for 976 Escherichia coli bloodstream infection isolates from Oxfordshire, United Kingdom, comparing against phenotypes from the BD Phoenix (calibrated against EUCAST guidelines). A total of 339/976 (35%) isolates were amoxicillin-clavulanate resistant. Predictions based solely on beta-lactamase presence/absence performed poorly (sensitivity, 23% [78/339]) but improved when genetic features associated with penicillinase hyperproduction (e.g., promoter mutations and copy number estimates) were considered (sensitivity, 82% [277/339]; P < 0.0001). Most discrepancies occurred in isolates with MICs within ±1 doubling dilution of the breakpoint. We investigated two potential causes: the phenotypic reference and the binary resistant/susceptible classification. We performed reference standard, replicated phenotyping in a random stratified subsample of 261/976 (27%) isolates using agar dilution, following both EUCAST and CLSI guidelines, which use different clavulanate concentrations. As well as disagreeing with each other, neither agar dilution phenotype aligned perfectly with genetic features. A random-effects model investigating associations between genetic features and MICs showed that some genetic features had small, variable and additive effects, resulting in variable resistance classification. Using model fixed-effects to predict MICs for the non-agar dilution isolates, predicted MICs were in essential agreement (±1 doubling dilution) with observed (BD Phoenix) MICs for 691/715 (97%) isolates. This suggests amoxicillin-clavulanate resistance in E. coli is quantitative, rather than qualitative, explaining the poorly reproducible binary (resistant/susceptible) phenotypes and suboptimal concordance between different phenotypic methods and with WGS-based predictions.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio , Escherichia coli , Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ácido Clavulânico/farmacologia , Escherichia coli/genética , Testes de Sensibilidade Microbiana , Fenótipo , Reino Unido , beta-Lactamases/genética
6.
J Virol ; 93(21)2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31434729

RESUMO

Jaagsiekte sheep retrovirus (JSRV) is the etiologic agent of ovine pulmonary adenocarcinoma (OPA), a neoplastic lung disease of sheep. OPA is an important economic and welfare issue for sheep farmers and a valuable naturally occurring animal model for human lung adenocarcinoma. Here, we used RNA sequencing to study the transcriptional response of ovine lung tissue to infection by JSRV. We identified 1,971 ovine genes differentially expressed in JSRV-infected lung compared to noninfected lung, including many genes with roles in carcinogenesis and immunomodulation. The differential expression of selected genes was confirmed using immunohistochemistry and reverse transcription-quantitative PCR. A key finding was the activation of anterior gradient 2, yes-associated protein 1, and amphiregulin in OPA tumor cells, indicating a role for this oncogenic pathway in OPA. In addition, there was differential expression of genes related to innate immunity, including genes encoding cytokines, chemokines, and complement system proteins. In contrast, there was little evidence for the upregulation of genes involved in T-cell immunity. Many genes related to macrophage function were also differentially expressed, reflecting the increased abundance of these cells in OPA-affected lung tissue. Comparison of the genes differentially regulated in OPA with the transcriptional changes occurring in human lung cancer revealed important similarities and differences between OPA and human lung adenocarcinoma. This study provides valuable new information on the pathogenesis of OPA and strengthens the use of this naturally occurring animal model for human lung adenocarcinoma.IMPORTANCE Ovine pulmonary adenocarcinoma is a chronic respiratory disease of sheep caused by jaagsiekte sheep retrovirus (JSRV). OPA is a significant economic problem for sheep farmers in many countries and is a valuable animal model for some forms of human lung cancer. Here, we examined the changes in host gene expression that occur in the lung in response to JSRV infection. We identified a large number of genes with altered expression in infected lung, including factors with roles in cancer and immune system function. We also compared the data from OPA to previously published data from human lung adenocarcinoma and found a large degree of overlap in the genes that were dysregulated. The results of this study provide exciting new avenues for future studies of OPA and may have comparative relevance for understanding human lung cancer.


Assuntos
Retrovirus Jaagsiekte de Ovinos/fisiologia , Pulmão/virologia , Adenomatose Pulmonar Ovina/genética , Adenocarcinoma de Pulmão/genética , Animais , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/genética , Adenomatose Pulmonar Ovina/metabolismo , Adenomatose Pulmonar Ovina/patologia , Adenomatose Pulmonar Ovina/virologia , Ovinos
7.
PLoS Biol ; 15(11): e2004044, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29190283

RESUMO

The Sonic Kayak is a musical instrument used to investigate nature and developed during open hacklab events. The kayaks are rigged with underwater environmental sensors, which allow paddlers to hear real-time water temperature sonifications and underwater sounds, generating live music from the marine world. Sensor data is also logged every second with location, time and date, which allows for fine-scale mapping of water temperatures and underwater noise that was previously unattainable using standard research equipment. The system can be used as a citizen science data collection device, research equipment for professional scientists, or a sound art installation in its own right.


Assuntos
Acústica , Monitoramento Ambiental , Música , Navios , Software , Temperatura
8.
BJU Int ; 125(4): 506-514, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31900963

RESUMO

OBJECTIVE: To test the hypothesis that the baseline clinico-pathological features of the men with localized prostate cancer (PCa) included in the ProtecT (Prostate Testing for Cancer and Treatment) trial who progressed (n = 198) at a 10-year median follow-up were different from those of men with stable disease (n = 1409). PATIENTS AND METHODS: We stratified the study participants at baseline according to risk of progression using clinical disease stage, pathological grade and PSA level, using Cox proportional hazard models. RESULTS: The findings showed that 34% of participants (n = 505) had intermediate- or high-risk PCa, and 66% (n = 973) had low-risk PCa. Of 198 participants who progressed, 101 (51%) had baseline International Society of Urological Pathology Grade Group 1, 59 (30%) Grade Group 2, and 38 (19%) Grade Group 3 PCa, compared with 79%, 17% and 5%, respectively, for 1409 participants without progression (P < 0.001). In participants with progression, 38% and 62% had baseline low- and intermediate-/high-risk disease, compared with 69% and 31% of participants with stable disease (P < 0.001). Treatment received, age (65-69 vs 50-64 years), PSA level, Grade Group, clinical stage, risk group, number of positive cores, tumour length and perineural invasion were associated with time to progression (P ≤ 0.005). Men progressing after surgery (n = 19) were more likely to have a higher Grade Group and pathological stage at surgery, larger tumours, lymph node involvement and positive margins. CONCLUSIONS: We demonstrate that one-third of the ProtecT cohort consists of people with intermediate-/high-risk disease, and the outcomes data at an average of 10 years' follow-up are generalizable beyond men with low-risk PCa.


Assuntos
Neoplasias da Próstata/patologia , Idoso , Estudos de Coortes , Progressão da Doença , Seguimentos , Humanos , Calicreínas/sangue , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Medição de Risco , Fatores de Tempo
9.
J Fish Biol ; 97(4): 964-973, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32613622

RESUMO

Predator-prey size (PPS) relationships are determined by predator behaviour, with the likelihood of prey being eaten dependent on their size relative to that of the consumer. Published PPS relationships for 30 pelagic or benthic marine fish species were analysed using quantile regression to determine how median, lower and upper prey sizes varied with predator size and habitat. Habitat effects on predator foraging activity/mode, morphology, growth and natural mortality are quantified and the effects on PPS relationships explored. Pelagic species are more active, more likely to move by caudal fin propulsion and grow more rapidly but have higher mortality rates than benthic species, where the need for greater manoeuvrability when foraging in more physically complex habitats favours ambush predators using pectoral fin propulsion. Prey size increased with predator size in most species, but pelagic species ate relatively smaller prey than benthic predators. As pelagic predators grew, lower prey size limits changed little, and prey size range increased but median relative prey size declined, whereas the lower limit increased and median relative prey size was constant or increased in benthic species.


Assuntos
Organismos Aquáticos/fisiologia , Tamanho Corporal/fisiologia , Ecossistema , Peixes/anatomia & histologia , Peixes/fisiologia , Animais , Comportamento Predatório
10.
Histopathology ; 74(3): 377-390, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30325065

RESUMO

AIMS: The International Collaboration on Cancer Reporting (ICCR) has provided detailed data sets based upon the published reporting protocols of the Royal College of Pathologists, the Royal College of Pathologists of Australasia and the College of American Pathologists. METHODS AND RESULTS: The data set for carcinomas of renal tubular origin treated by nephrectomy was developed to provide a minimum structured reporting template suitable for international use, and incorporated recommendations from the 2012 Vancouver Consensus Conference of the International Society of Urological Pathology (ISUP) and the fourth edition of the World Health Organisation Bluebook on tumours of the urinary and male genital systems published in 2016. Reporting elements were divided into those, which are required and recommended components of the report. Required elements are: specimen laterality, operative procedure, attached structures, tumour focality, tumour dimension, tumour type, WHO/ISUP grade, sarcomatoid/rhabdoid morphology, tumour necrosis, extent of invasion, lymph node status, surgical margin status, AJCC TNM staging and co-existing pathology. Recommended reporting elements are: pre-operative treatment, details of tissue removed for experimental purposes prior to submission, site of tumour(s) block identification key, extent of sarcomatoid and/or rhabdoid component, extent of necrosis, presence of tumour in renal vein wall, lymphovascular invasion and lymph node status (size of largest focus and extranodal extension). CONCLUSIONS: It is anticipated that the implementation of this data set in routine clinical practice will inform patient treatment as well as provide standardised information relating to outcome prediction. The harmonisation of data reporting should also facilitate international research collaborations.


Assuntos
Carcinoma de Células Renais , Conjuntos de Dados como Assunto/normas , Neoplasias Renais , Projetos de Pesquisa/normas , Australásia , Humanos , Patologia Clínica/métodos , Patologia Clínica/normas
11.
Cell Biol Toxicol ; 35(3): 219-232, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30426330

RESUMO

The polyether toxin, okadaic acid, causes diarrhetic shellfish poisoning in humans. Despite extensive research into its cellular targets using rodent models, we know little about its putative effect(s) on innate immunity. We inoculated larvae of the greater wax moth, Galleria mellonella, with physiologically relevant doses of okadaic acid by direct injection into the haemocoel (body cavity) and/or gavage (force-feeding). We monitored larval survival and employed a range of cellular and biochemical assays to assess the potential harmful effects of okadaic acid. Okadaic acid at concentrations ≥ 75 ng/larva (≥ 242 µg/kg) led to significant reductions in larval survival (> 65%) and circulating haemocyte (blood cell) numbers (> 50%) within 24 h post-inoculation. In the haemolymph, okadaic acid reduced haemocyte viability and increased phenoloxidase activities. In the midgut, okadaic acid induced oxidative damage as determined by increases in superoxide dismutase activity and levels of malondialdehyde (i.e. lipid peroxidation). Our observations of insect larvae correspond broadly to data published using rodent models of shellfish-poisoning toxidrome, including complementary LD50 values: 206-242 µg/kg in mice, ~ 239 µg/kg in G. mellonella. These data support the use of this insect as a surrogate model for the investigation of marine toxins, which offers distinct ethical and financial incentives.


Assuntos
Mariposas/efeitos dos fármacos , Ácido Okadáico/toxicidade , Animais , Insetos/efeitos dos fármacos , Larva/efeitos dos fármacos , Lepidópteros/efeitos dos fármacos , Modelos Animais , Oxirredução , Intoxicação por Frutos do Mar/fisiopatologia
12.
Clin Infect Dis ; 67(9): 1379-1387, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-29659753

RESUMO

Background: No study has used whole-genome sequencing (WGS) to investigate risk factors for Clostridium difficile (CD) transmission between cases, or assessed the impact of recent acquisition on patient outcome. Methods: This 20 month retrospective cohort study included consecutive cytotoxin-positive diarrheal samples, which underwent culture, ribotyping, and WGS (Illumina). Sequenced isolates were compared using single nucleotide variants (SNVs). Independent predictors of acquisition from another case, onward transmission, 120-day recurrence, and 30-day mortality were identified using logistic regression with backwards elimination. Results: Of 660 CD cases, 640 (97%) were sequenced, of which 567 (89%) shared a ribotype with a prior case, but only 227 (35%) were ≤2 SNVs from a prior case, supporting recent acquisition. Plausible (<2 SNVs) recent ward-based acquisition from a symptomatic case was more frequent in certain ribotypes; 64% (67/105) for ribotype-027 cases, compared with 11% (6/57) for ribotype-078. Independent risk factors (adjusted P < .05) for CD acquisition included older age, longer inpatient duration, and ribotype; these factors, and male sex, increased onward transmission. Patients with a plausible donor had a greater risk of recurrence (adjusted P = .001) and trended towards greater 30-day mortality (adjusted P = .06). Ribotype had no additional mortality or recurrence impact after adjusting for acquisition (P > .1). Conclusions: Greater transmission of certain lineages suggests CD may have different reservoirs and modes of transmission. Acquiring CD from a recent case is associated with poorer clinical outcomes. Clinical characteristics associated with increased healthcare-associated CD transmission could be used to target preventative interventions.


Assuntos
Clostridioides difficile/classificação , Infecções por Clostridium/mortalidade , Infecções por Clostridium/transmissão , Pacientes Internados , Idoso , Idoso de 80 Anos ou mais , Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/microbiologia , Diarreia/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Ribotipagem , Fatores de Risco , Sequenciamento Completo do Genoma
13.
J Pathol ; 243(4): 442-456, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29134654

RESUMO

Aberrant phosphoinositide 3-kinase (PI3K), mitogen-activated protein kinase (MAPK) and WNT signalling are emerging as key events in the multistep nature of prostate tumourigenesis and progression. Here, we report a compound prostate cancer murine model in which these signalling pathways cooperate to produce a more aggressive prostate cancer phenotype. Using Cre-LoxP technology and the probasin promoter, we combined the loss of Pten (Ptenfl/fl ), to activate the PI3K signalling pathway, with either dominant stabilized ß-catenin [Catnb+/lox(ex3) ] or activated K-RAS (K-Ras+/V12 ) to aberrantly activate WNT and MAPK signalling, respectively. Synchronous activation of all three pathways (triple mutants) significantly reduced survival (median 96 days) as compared with double mutants [median: 140 days for Catnb+/lox(ex3) Ptenfl/fl ; 182 days for Catnb+/lox(ex3) K-Ras+/V12 ; 238 days for Ptenfl/fl K-Ras+/V12 ], and single mutants [median: 383 days for Catnb+/lox(ex3) ; 407 days for Ptenfl/fl ], reflecting the accelerated tumourigenesis. Tumours followed a stepwise progression from mouse prostate intraepithelial neoplasia to invasive adenocarcinoma, similar to that seen in human disease. There was significantly elevated cellular proliferation, tumour growth and percentage of invasive adenocarcinoma in triple mutants as compared with double mutants and single mutants. Triple mutants showed not only activated AKT, extracellular-signal regulated kinase 1/2, and nuclear ß-catenin, but also significantly elevated signalling through mechanistic target of rapamycin complex 1 (mTORC1). In summary, we show that combined deregulation of the PI3K, MAPK and WNT signalling pathways drives rapid progression of prostate tumourigenesis, and that deregulation of all three pathways results in tumours showing aberrant mTORC1 signalling. As mTORC1 signalling is emerging as a key driver of androgen deprivation therapy resistance, our findings are important for understanding the biology of therapy-resistant prostate cancer and identifying potential approaches to overcome this. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Adenocarcinoma/enzimologia , Transformação Celular Neoplásica/metabolismo , PTEN Fosfo-Hidrolase/deficiência , Neoplasia Prostática Intraepitelial/enzimologia , Neoplasias da Próstata/enzimologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , beta Catenina/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Progressão da Doença , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Predisposição Genética para Doença , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Knockout , Mutação , PTEN Fosfo-Hidrolase/genética , Fenótipo , Fosfatidilinositol 3-Quinase/metabolismo , Neoplasia Prostática Intraepitelial/genética , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Fatores de Tempo , Carga Tumoral , Via de Sinalização Wnt , beta Catenina/genética
14.
Philos Trans A Math Phys Eng Sci ; 376(2134)2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-30373948

RESUMO

Electromagnetic fields carry momentum: [Formula: see text] But if the centre of energy of a (localized) system is at rest, its total momentum must be zero. The compensating term has come to be called 'hidden' momentum: P h = - P em It is (typically) ordinary mechanical momentum, relativistic in nature, and is 'hidden' only in the sense that it is not associated with motion of the system as a whole-only with that of its constituent parts. This article develops a catalogue of field momenta and hidden momenta for ideal electric and magnetic dipoles-both the 'standard' variety made from electric charges and currents and the 'anomalous' variety made from hypothetical magnetic monopoles and their currents-in the presence of electric and magnetic fields (which themselves may be produced by 'standard' or 'anomalous' sources).This article is part of the theme issue 'Celebrating 125 years of Oliver Heaviside's 'Electromagnetic Theory''.

15.
Regul Toxicol Pharmacol ; 94: 22-32, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29309809

RESUMO

Acute inhalation studies are conducted in animals as part of chemical hazard identification and for classification and labelling. Current methods employ death as an endpoint (Organisation for Economic Co-operation and Development (OECD) test guideline (TG) 403 and TG436) while the recently approved fixed concentration procedure (FCP) (OECD TG433) uses fewer animals and replaces lethality as an endpoint with evident toxicity. Evident toxicity is the presence of clinical signs that predict that exposure to the next highest concentration will cause severe toxicity or death in most animals. Approval of TG433 was the result of an international initiative, led by the National Centre for the Replacement, Refinement & Reduction of Animals in Research (NC3Rs), which collected data from six laboratories on clinical signs recorded for inhalation studies on 172 substances. This paper summarises previously published data and describes the additional analyses of the dataset that were essential for approval of the TG.


Assuntos
Testes de Toxicidade Aguda/métodos , Administração por Inalação , Alternativas ao Uso de Animais/métodos , Animais , Feminino , Masculino
16.
Soc Stud Sci ; 48(1): 125-148, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29424285

RESUMO

The 2006 'Consensus statement on management of intersex disorders' recommended moving to a new classification of intersex variations, framed in terms of 'disorders of sex development' or DSD. Part of the rationale for this change was to move away from associations with gender, and to increase clarity by grounding the classification system in genetics. While the medical community has largely accepted the move, some individuals from intersex activist communities have condemned it. In addition, people both inside and outside the medical community have disagreed about what should be covered by the classification system, in particular whether sex chromosome variations and the related diagnoses of Turner and Klinefelter's syndromes should be included. This article explores initial descriptions of Turner and Klinefelter's syndromes and their subsequent inclusion in intersex classifications, which were increasingly grounded in scientific understandings of sex chromosomes that emerged in the 1950s. The article questions the current drive to stabilize and 'sort out' intersex classifications through a grounding in genetics. Alternative social and historical definitions of intersex - such as those proposed by the intersex activists - have the potential to do more justice to the lived experience of those affected by such classifications and their consequences.


Assuntos
Transtornos do Desenvolvimento Sexual/história , Síndrome de Klinefelter/história , Síndrome de Turner/história , Transtornos do Desenvolvimento Sexual/classificação , Transtornos do Desenvolvimento Sexual/diagnóstico , História do Século XX , História do Século XXI , Humanos , Síndrome de Klinefelter/classificação , Síndrome de Klinefelter/diagnóstico , Síndrome , Síndrome de Turner/classificação , Síndrome de Turner/diagnóstico
17.
Sexualities ; 21(3): 476-495, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29568226

RESUMO

The medical 'management' of individuals with atypical sex characteristics, or intersex variations, has been under scrutiny since the beginnings of intersex activism in the 1990s. This article explores a history of intersex surgeries in Britain and the interaction with medical and popular discourses around 'sex-change' between 1930 and 1955. A focus on this period in Britain helps to critically elaborate on debates in intersex scholarship; provides historical context for the introduction of approaches and protocols based on John Money and colleagues' work in the USA in the mid-century; and analyses a long history of tension and intersection between trans and intersex experiences, treatments, politics and popular representations that continue into the present.

18.
Clin Infect Dis ; 64(9): 1163-1170, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28158441

RESUMO

Background: The role of symptomatic patients who are toxigenic strain positive (TS+) but fecal toxin negative (FT-) in transmission of Clostridium difficile is currently unknown. Methods: We investigated the contribution of symptomatic TS+/FT- and TS+/FT+ patients in C. difficile transmission in 2 UK regions. From 2-step testing, all glutamate dehydrogenase (GDH)-positive specimens, regardless of fecal toxin result, from Oxford (April 2012 through April 2013) and Leeds (July 2012 through April 2013) microbiology laboratories underwent culture and whole-genome sequencing (WGS), using WGS to identify toxigenic strains. Plausible sources for each TS+/FT+ case, including TS+/FT- and TS+/FT+ patients, were determined using WGS, with and without hospital admission data. Results: A total of 1447 of 12772 (11%) fecal samples were GDH positive, 866 of 1447 (60%) contained toxigenic C. difficile, and fecal toxin was detected in 511 of 866 (59%), representing 235 Leeds and 191 Oxford TS+/FT+ cases. TS+/FT+ cases were 3 times more likely to be plausibly acquired from a previous TS+/FT+ case than a TS+/FT- patient. Fifty-one of 265 (19%) TS+/FT+ cases diagnosed >3 months into the study were genetically related (≤2 single-nucleotide polymorphisms) to ≥1 previous TS+/FT+ case or TS+/FT- patient: 27 (10%) to only TS+/FT+ cases, 9 (3%) to only TS+/FT- patients, and 15 (6%) to both. Only 10 of 265 (4%) were genetically related to a previous TS+/FT+ or TS+/FT- patient and shared the same ward simultaneously or within 28 days. Conclusions: Symptomatic TS+/FT- patients were a source of C. difficile transmission, although they accounted for less onward transmission than TS+/FT+ cases. Although transmission from symptomatic patients with either fecal toxin status accounted for a low overall proportion of new cases, both groups should be infection control targets.


Assuntos
Toxinas Bacterianas/análise , Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/transmissão , Transmissão de Doença Infecciosa , Fezes/química , Fezes/microbiologia , Idoso , Idoso de 80 Anos ou mais , Técnicas Bacteriológicas , Clostridioides difficile/classificação , Clostridioides difficile/genética , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/patologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Tipagem Molecular , Análise de Sequência de DNA , Reino Unido/epidemiologia
19.
N Engl J Med ; 369(13): 1195-205, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-24066741

RESUMO

BACKGROUND: It has been thought that Clostridium difficile infection is transmitted predominantly within health care settings. However, endemic spread has hampered identification of precise sources of infection and the assessment of the efficacy of interventions. METHODS: From September 2007 through March 2011, we performed whole-genome sequencing on isolates obtained from all symptomatic patients with C. difficile infection identified in health care settings or in the community in Oxfordshire, United Kingdom. We compared single-nucleotide variants (SNVs) between the isolates, using C. difficile evolution rates estimated on the basis of the first and last samples obtained from each of 145 patients, with 0 to 2 SNVs expected between transmitted isolates obtained less than 124 days apart, on the basis of a 95% prediction interval. We then identified plausible epidemiologic links among genetically related cases from data on hospital admissions and community location. RESULTS: Of 1250 C. difficile cases that were evaluated, 1223 (98%) were successfully sequenced. In a comparison of 957 samples obtained from April 2008 through March 2011 with those obtained from September 2007 onward, a total of 333 isolates (35%) had no more than 2 SNVs from at least 1 earlier case, and 428 isolates (45%) had more than 10 SNVs from all previous cases. Reductions in incidence over time were similar in the two groups, a finding that suggests an effect of interventions targeting the transition from exposure to disease. Of the 333 patients with no more than 2 SNVs (consistent with transmission), 126 patients (38%) had close hospital contact with another patient, and 120 patients (36%) had no hospital or community contact with another patient. Distinct subtypes of infection continued to be identified throughout the study, which suggests a considerable reservoir of C. difficile. CONCLUSIONS: Over a 3-year period, 45% of C. difficile cases in Oxfordshire were genetically distinct from all previous cases. Genetically diverse sources, in addition to symptomatic patients, play a major part in C. difficile transmission. (Funded by the U.K. Clinical Research Collaboration Translational Infection Research Initiative and others.).


Assuntos
Clostridioides difficile/genética , Infecções por Clostridium/transmissão , Infecção Hospitalar/transmissão , Idoso , Idoso de 80 Anos ou mais , Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , DNA Bacteriano/análise , Transmissão de Doença Infecciosa , Feminino , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Incidência , Masculino , Análise de Sequência de DNA , Reino Unido
20.
J Virol ; 89(1): 35-47, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25320307

RESUMO

UNLABELLED: Merkel cell carcinoma (MCC) is an aggressive skin cancer of neuroendocrine origin with a high propensity for recurrence and metastasis. Merkel cell polyomavirus (MCPyV) causes the majority of MCC cases due to the expression of the MCPyV small and large tumor antigens (ST and LT, respectively). Although a number of molecular mechanisms have been attributed to MCPyV tumor antigen-mediated cellular transformation or replication, to date, no studies have investigated any potential link between MCPyV T antigen expression and the highly metastatic nature of MCC. Here we use a quantitative proteomic approach to show that MCPyV ST promotes differential expression of cellular proteins implicated in microtubule-associated cytoskeletal organization and dynamics. Intriguingly, we demonstrate that MCPyV ST expression promotes microtubule destabilization, leading to a motile and migratory phenotype. We further highlight the essential role of the microtubule-associated protein stathmin in MCPyV ST-mediated microtubule destabilization and cell motility and implicate the cellular phosphatase catalytic subunit protein phosphatase 4C (PP4C) in the regulation of this process. These findings suggest a possible molecular mechanism for the highly metastatic phenotype associated with MCC. IMPORTANCE: Merkel cell polyomavirus (MCPyV) causes the majority of cases of Merkel cell carcinoma (MCC), an aggressive skin cancer with a high metastatic potential. However, the molecular mechanisms leading to virally induced cancer development have yet to be fully elucidated. In particular, no studies have investigated any potential link between the virus and the highly metastatic nature of MCC. We demonstrate that the MCPyV small tumor antigen (ST) promotes the destabilization of the host cell microtubule network, which leads to a more motile and migratory cell phenotype. We further show that MCPyV ST induces this process by regulating the phosphorylation status of the cellular microtubule-associated protein stathmin by its known association with the cellular phosphatase catalytic subunit PP4C. These findings highlight stathmin as a possible biomarker of MCC and as a target for novel antitumoral therapies.


Assuntos
Antígenos Virais de Tumores/metabolismo , Movimento Celular , Interações Hospedeiro-Patógeno , Poliomavírus das Células de Merkel/fisiologia , Microtúbulos/metabolismo , Linhagem Celular , Perfilação da Expressão Gênica , Humanos , Fosfoproteínas Fosfatases/metabolismo , Proteoma/análise , Estatmina/metabolismo
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