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1.
Nat Commun ; 14(1): 267, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650172

RESUMO

Developmental control of gene expression critically depends on distal cis-regulatory elements including enhancers which interact with promoters to activate gene expression. To date no global experiments have been conducted that identify their cell type and cell stage-specific activity within one developmental pathway and in a chromatin context. Here, we describe a high-throughput method that identifies thousands of differentially active cis-elements able to stimulate a minimal promoter at five stages of hematopoietic progenitor development from embryonic stem (ES) cells, which can be adapted to any ES cell derived cell type. We show that blood cell-specific gene expression is controlled by the concerted action of thousands of differentiation stage-specific sets of cis-elements which respond to cytokine signals terminating at signalling responsive transcription factors. Our work provides an important resource for studies of hematopoietic specification and highlights the mechanisms of how and where extrinsic signals program a cell type-specific chromatin landscape driving hematopoietic differentiation.


Assuntos
Cromatina , Sequências Reguladoras de Ácido Nucleico , Cromatina/genética , Diferenciação Celular/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regiões Promotoras Genéticas/genética , Elementos Facilitadores Genéticos/genética
2.
BMJ Mil Health ; 169(e1): e86-e89, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-33127871

RESUMO

The Craig Joint Theater Hospital at Bagram Airfield is the coalition role 3 facility for the North Atlantic Treaty Organization-led Operation RESOLUTE SUPPORT in northern Afghanistan. The onset of the global COVID-19 pandemic in early 2020 presented the challenges of limiting viral transmission, disease force protection, specific protection of healthcare workers and management of patients with COVID-19, all while continuing to provide high-quality care for battlefield trauma. The estimated COVID-19 threat led to the introduction of enhanced force protection measures across the Combined Joint Operations Area-Afghanistan. Surveillance testing of high-risk groups at coalition locations was established. Non-essential movements were restricted and quarantine periods instigated. Protection of healthcare workers and patients was improved with enhanced personal protective equipment as well as structural, procedural and personnel changes across the role 3 facility in order to limit viral exposure and transmission. This occurred in a resource-limited environment without degrading overall clinical capability.


Assuntos
COVID-19 , Humanos , Afeganistão , Pandemias/prevenção & controle , Equipamento de Proteção Individual
3.
Ann Vasc Surg ; 75: 287-293, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33819582

RESUMO

OBJECTIVES: Tunneled central venous catheter infection (TCVCi) is a common complication that often necessitates removal of the TCVC and replacement by a further TCVC. Theoretically, insertion of an early - cannulation graft (ecAVG) early after TCVC infection is possible but not widely practiced with concerns over safety and infection in the ecAVG. With 8 years of ecAVG experience, the aim of this study was to compare the outcomes following TCVC infection, comparing replacement with TCVC (TCVCr) versus immediate ecAVG (ecAVGr). DESIGN: Retrospective comparison of 2 cohorts, who underwent replacement of an infected TCVC either by an early cannulation graft (n = 18) or by a further central catheter (n = 39). METHODS: Data were abstracted from a prospectively completed electronic patient record and collected on patient demographics, TCVC insertion, duration and infection, including culture proven bacteriaemia and subsequent access interventions. RESULTS: Eighteen of 299 patients identified from 2012 to 2020 had an ecAVG implanted as treatment for a TCVCi. In a 1-year time-period (January 1, 2015-December 31, 2015) out of 222 TCVC inserted, 39 were as a replacement following a TCVCi. No patient with an ecAVGr developed an immediate infection, nor complication from the procedure. The rate of subsequent vascular access infection was significantly more frequent for those with a TCVCr than with an ecAVGr (0.6 vs. 0.1/patient/1000 HD days, P< 0.000). The number of further TCVC required was significantly higher in the TCVCr group (7.1 vs. 0.4/patient/1000 HD days, P= 0.000). CONCLUSIONS: An ecAVG early following a TCVC infection is safe, reduces the incidence of subsequent infectious complications and reduces the number of TCVC required, with a better functional patency.


Assuntos
Derivação Arteriovenosa Cirúrgica , Infecções Relacionadas a Cateter/prevenção & controle , Cateterismo Venoso Central/efeitos adversos , Cateterismo , Cateteres de Demora/efeitos adversos , Cateteres Venosos Centrais/efeitos adversos , Diálise Renal , Idoso , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Infecções Relacionadas a Cateter/diagnóstico , Infecções Relacionadas a Cateter/microbiologia , Cateterismo Venoso Central/instrumentação , Remoção de Dispositivo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reinfecção , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
4.
N Z Vet J ; 69(3): 190-191, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33689588
5.
Environ Sci Pollut Res Int ; 28(1): 754-762, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32822011

RESUMO

The extraction, transport, and consumption of hydrocarbons occur daily worldwide and can lead to environmental pollution and significant incidents of wildlife mortality. This review of literature and publicly available databases from 1970 to 2018 summarises records on oil spill incidents, sources of spills, and reported effects on wildlife. During this time period, millions of tonnes of oil were released from over 1700 acute oil spills, with only 312 (18%) reporting wildlife effects. The most numerous reported spill source was shipping. From this review, there are obvious global gaps in reporting of oil spills and recording of effects on wildlife. We recommend there is a global need for increased consistency of reporting and availability of data of oil spills, and wildlife impacts. This information is critical to preparedness and response procedures for industry (shipping and oil) and governments.


Assuntos
Poluição por Petróleo , Poluição Ambiental , Indústrias , Navios
6.
Rev Endocr Metab Disord ; 22(3): 647-663, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33155118

RESUMO

The rapid evolution of novel, costly therapies for neuroendocrine neoplasia (NEN) warrants formal high-quality cost-effectiveness evaluation. Costs of individual investigations and therapies are high; and examples are presented. We aimed to review the last ten years of standalone health economic evaluations in NEN. Comparing to published standards, EMBASE, Cochrane library, Database of Abstracts of Reviews of Effects (DARE), NHS Economic Evaluation Database and the Health Technology Assessment (HTA) Database were searched for health economic evaluations (HEEs) in NEN published between 2010 and October 2019. Of 12 economic evaluations, 11 considered exclusively pharmacological treatment (3 studies of SSAs, 7 studies of sunitinib, everolimus and/or 177Lu-DOTATATE and 1 study of telotristat ethyl) and 1 compared surgery with intraarterial therapy. 7 studies of pharmacological treatment had placebo or best supportive care as the only comparator. There remains a paucity of economic evaluations in NEN with the majority industry funded. Most HEEs reviewed did not meet published health economic criteria used to assess quality. Lack of cost data collected from patient populations remains a significant factor in HEEs where clinical expert opinion is still often substituted. Further research utilizing high-quality effectiveness data and rigorous applied health economic analysis is needed.


Assuntos
Tumores Neuroendócrinos , Análise Custo-Benefício , Humanos , Tumores Neuroendócrinos/terapia , Tomografia por Emissão de Pósitrons , Cintilografia , Avaliação da Tecnologia Biomédica
7.
BJOG ; 126(12): 1456-1465, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31449731

RESUMO

OBJECTIVE: To quantify geographic variation in the use of lymphadenectomy and/or external-beam radiotherapy (EBRT) for endometrial cancer in England. DESIGN: Cross-sectional analysis of population-based data. SETTING: English cancer registry data, linked to chemotherapy, radiotherapy and hospital episodes statistics data. POPULATION: Twenty-two thousand four hundred and eighty-three women with endometrial cancer presenting without clinical or radiological evidence of distant metastatic spread, diagnosed in England from 2013 to 2016. METHODS: Proportions of patients receiving lymphadenectomy and/or EBRT were compared across 19 Cancer Alliances, to identify variations in clinical practice. Two separate logistic regression models assessed the impact on variation of adjustment for tumour and patient characteristics. MAIN OUTCOME MEASURES: Receipt of lymphadenectomy, receipt of EBRT. RESULTS: There was substantial variation by Cancer Alliance in the adjusted proportion of women with endometrial cancer receiving lymphadenectomy (range 5% [95% CI 4-6%] to 48% [95% CI 45-52%]) and EBRT (range 10% [95% CI 7-12%] to 31% [95% CI 28-33%]), after adjusting for variation in pathological grade, age, comorbidities, deprivation, ethnic group and (EBRT only) FIGO stage. Different approaches to clinical practice were identified; (i) one Cancer Alliance had significantly higher than average lymphadenectomy and significantly lower than average EBRT use, (ii) three had high use of both lymphadenectomy and EBRT, (iii) one had low lymphadenectomy use and high EBRT use, and (iv) three had low use of both lymphadenectomy and EBRT. CONCLUSIONS: Lymphadenectomy is probably used to triage for EBRT when lymphadenectomy use is high and EBRT use is low. This is probably a result of variation in local endometrial cancer management guidelines, suggesting that UK recommendations should be clarified. TWEETABLE ABSTRACT: There is geographic variation in England in the use of lymphadenectomy and radiotherapy to treat endometrial cancer.


Assuntos
Adenocarcinoma/terapia , Neoplasias do Endométrio/terapia , Adenocarcinoma/secundário , Adulto , Estudos Transversais , Neoplasias do Endométrio/patologia , Inglaterra , Feminino , Geografia , Humanos , Modelos Logísticos , Excisão de Linfonodo/estatística & dados numéricos , Metástase Neoplásica , Vigilância da População , Radioterapia Adjuvante/estatística & dados numéricos , Sistema de Registros , Medicina Estatal , Serviços de Saúde da Mulher
8.
Endocrinology ; 159(9): 3378-3388, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30060079

RESUMO

Atrazine (ATR) is a commonly used pre-emergence and early postemergence herbicide. Rats gavaged with ATR and its chlorometabolites desethylatrazine (DEA) and deisopropylatrazine (DIA) respond with a rapid and dose-dependent rise in plasma corticosterone, whereas the major chlorometabolite, diaminochlorotriazine (DACT), has little or no effect on corticosterone levels. In this study, we investigated the possible sites of ATR activation of the hypothalamic-pituitary-adrenal (HPA) axis. ATR treatment had no effect on adrenal weights but altered adrenal morphology. Hypophysectomized rats or rats under dexamethasone suppression did not respond to ATR treatment, suggesting that ATR does not directly stimulate the adrenal gland to induce corticosterone synthesis. Immortalized mouse corticotrophs (AtT-20) and primary rat pituitary cultures were treated with ATR, DEA, DIA, or DACT. None of the compounds induced an increase in ACTH secretion or potentiated ACTH release in conjunction with CRH on ACTH release. In female rats gavaged with ATR, pretreatment with the CRH receptor antagonist astressin completely blocked the ATR-induced rise in corticosterone concentrations, implicating CRH release in ATR-induced HPA activation. Intracerebroventricular infusion of ATR, DEA, and DIA but not DACT at concentrations equivalent to peak plasma concentrations after gavage dosing resulted in an elevation of plasma corticosterone concentrations. However, ATR did not induce c-Fos immunoreactivity in the paraventricular nucleus of the hypothalamus. These results indicate that ATR activates the HPA axis centrally and requires CRH receptor activation, but it does not stimulate cellular pathways associated with CRH neuronal excitation.


Assuntos
Atrazina/farmacologia , Corticotrofos/efeitos dos fármacos , Herbicidas/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Hipófise/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/patologia , Hormônio Adrenocorticotrópico/efeitos dos fármacos , Hormônio Adrenocorticotrópico/metabolismo , Animais , Atrazina/análogos & derivados , Linhagem Celular , Corticosterona/metabolismo , Corticotrofos/metabolismo , Dexametasona/farmacologia , Feminino , Glucocorticoides/farmacologia , Sistema Hipotálamo-Hipofisário/metabolismo , Camundongos , Técnicas de Cultura de Órgãos , Tamanho do Órgão , Hipófise/metabolismo , Hipófise/cirurgia , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Triazinas/farmacologia
9.
Gut Microbes ; 9(2): 115-130, 2018 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-28862530

RESUMO

Exercise reduces the risk of inflammatory disease by modulating a variety of tissue and cell types, including those within the gastrointestinal tract. Recent data indicates that exercise can also alter the gut microbiota, but little is known as to whether these changes affect host function. Here, we use a germ-free (GF) animal model to test whether exercise-induced modifications in the gut microbiota can directly affect host responses to microbiota colonization and chemically-induced colitis. Donor mice (n = 19) received access to a running wheel (n = 10) or remained without access (n = 9) for a period of six weeks. After euthanasia, cecal contents were pooled by activity treatment and transplanted into two separate cohorts of GF mice. Two experiments were then conducted. First, mice were euthanized five weeks after the microbiota transplant and tissues were collected for analysis. A second cohort of GF mice were colonized by donor microbiotas for four weeks before dextran-sodium-sulfate was administered to induce acute colitis, after which mice were euthanized for tissue analysis. We observed that microbial transplants from donor (exercised or control) mice led to differences in microbiota ß-diversity, metabolite profiles, colon inflammation, and body mass in recipient mice five weeks after colonization. We also demonstrate that colonization of mice with a gut microbiota from exercise-trained mice led to an attenuated response to chemical colitis, evidenced by reduced colon shortening, attenuated mucus depletion and augmented expression of cytokines involved in tissue regeneration. Exercise-induced modifications in the gut microbiota can mediate host-microbial interactions with potentially beneficial outcomes for the host.


Assuntos
Ceco/microbiologia , Colite/prevenção & controle , Colo/imunologia , Microbioma Gastrointestinal/fisiologia , Homeostase/fisiologia , Condicionamento Físico Animal/fisiologia , Animais , Peso Corporal , Ceco/metabolismo , Colite/induzido quimicamente , Colo/anatomia & histologia , Colo/patologia , Citocinas/genética , Sulfato de Dextrana/administração & dosagem , Modelos Animais de Doenças , Ácidos Graxos Voláteis/análise , Transplante de Microbiota Fecal , Feminino , Regulação da Expressão Gênica/imunologia , Vida Livre de Germes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fatores Sexuais
10.
Clin Obes ; 8(2): 105-113, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29224241

RESUMO

Evidence shows that surgery for severe obesity in adults improves health and psychological functioning, and is cost-effective. Data on bariatric surgery for adolescents with severe obesity are extremely limited, with no evidence on cost-effectiveness. We evaluated the lifetime cost-effectiveness of bariatric surgery compared with no surgery in adolescents with severe obesity from the UK's National Health Service perspective. Eighteen adolescents with body mass index ≥40 kg m-2 who underwent bariatric surgery (laparoscopic Roux en Y Gastric Bypass [RYGB] [N = 9], and laparoscopic Sleeve Gastrectomy [SG] [N = 9]) at University College London Hospitals between January 2008 and December 2013 were included. We used a Markov cohort model to compare the lifetime expected costs and quality-adjusted life years (QALYs) between bariatric surgery and no surgery. Mean cost of RYGB and SG procedures were £7100 and £7312, respectively. For RYGB vs. no surgery, the incremental cost/QALY was £2018 (95% CI £1942 - £2042) for males and £2005 (95% CI £1974 - £2031) for females. For SG vs. no surgery, the incremental cost/QALY was £1978 (95% CI £1954 - £2002) for males and £1941 (95% CI £1915 - £1969) for females. Bariatric surgery in adolescents with severe obesity is cost-effective; it is more costly than no surgery however it markedly improved quality of life.


Assuntos
Saúde do Adolescente/economia , Derivação Gástrica/economia , Obesidade Mórbida/economia , Obesidade Mórbida/cirurgia , Adolescente , Índice de Massa Corporal , Análise Custo-Benefício , Feminino , Gastrectomia/economia , Humanos , Masculino , Qualidade de Vida , Reino Unido , Adulto Jovem
11.
Ann Oncol ; 28(12): 3076-3082, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28950321

RESUMO

BACKGROUND: Reconstruction of clonal evolution is critical for understanding tumor progression and implementing personalized therapies. This is often done by clustering somatic variants based on their cellular prevalence estimated via bulk tumor sequencing of multiple samples. The clusters, consisting of the clonal marker variants, are then ordered based on their estimated cellular prevalence to reconstruct clonal evolution trees, a process referred to as 'clonal ordering'. However, cellular prevalence estimate is confounded by statistical variability and errors in sequencing/data analysis, and therefore inhibits accurate reconstruction of the clonal evolution. This problem is further complicated by intra- and inter-tumor heterogeneity. Furthermore, the field lacks a comprehensive visualization tool to facilitate the interpretation of complex clonal relationships. To address these challenges we developed ClonEvol, a unified software tool for clonal ordering, visualization, and interpretation. MATERIALS AND METHODS: ClonEvol uses a bootstrap resampling technique to estimate the cellular fraction of the clones and probabilistically models the clonal ordering constraints to account for statistical variability. The bootstrapping allows identification of the sample founding- and sub-clones, thus enabling interpretation of clonal seeding. ClonEvol automates the generation of multiple widely used visualizations for reconstructing and interpreting clonal evolution. RESULTS: ClonEvol outperformed three of the state of the art tools (LICHeE, Canopy and PhyloWGS) for clonal evolution inference, showing more robust error tolerance and producing more accurate trees in a simulation. Building upon multiple recent publications that utilized ClonEvol to study metastasis and drug resistance in solid cancers, here we show that ClonEvol rediscovered relapsed subclones in two published acute myeloid leukemia patients. Furthermore, we demonstrated that through noninvasive monitoring ClonEvol recapitulated the emerging subclones throughout metastatic progression observed in the tumors of a published breast cancer patient. CONCLUSIONS: ClonEvol has broad applicability for longitudinal monitoring of clonal populations in tumor biopsies, or noninvasively, to guide precision medicine. AVAILABILITY: ClonEvol is written in R and is available at https://github.com/ChrisMaherLab/ClonEvol.


Assuntos
Evolução Clonal , Leucemia Mieloide Aguda/genética , Células Clonais , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Leucemia Mieloide Aguda/patologia , Medicina de Precisão
12.
Haemophilia ; 23(5): 712-720, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28752601

RESUMO

INTRODUCTION: Prior to the introduction of viral inactivation of factor concentrates and screening of blood, 225 people with haemophilia became infected with hepatitis C (HCV) in Ireland. AIM: Our aim was to assess liver disease progression and mortality in this population after 30 years of infection. METHODS: Demographic and clinical data were collected from medical records in five hepatology units and one infectious disease unit retrospectively in 2005, and on four subsequent occasions. RESULTS: The participation rate was 73% (165/225). Eighty three percent of patients, who had been tested for RNA (n = 106/128), developed chronic HCV infection. Thirty four percent were co-infected with HIV. All-cause mortality, after approximately 30 years of infection with chronic HCV, was 44% in HIV positive patients and 29% in HIV negative patients. Liver-related mortality was 12.5% and did not vary significantly by HIV status. Thirty seven percent of patients had developed advanced liver disease, including 20% with cirrhosis and 9% with hepatocellular carcinoma. In the pre-interferon-free direct acting antivirals era, 57% (n = 60/106) of patients were treated for HCV, 65% of whom achieved a sustained virological response. Successfully treated patients had few adverse liver outcomes. CONCLUSION: After 30 years of infection, 40% of the patients who had evidence of chronic HCV had developed advanced liver disease, such as cirrhosis and HCC, or had died from liver-related causes. This proportion is high relative to similar international cohorts despite good anti-HCV treatment uptake and responses.


Assuntos
Hemofilia A/complicações , Hemofilia A/epidemiologia , Hemofilia B/complicações , Hemofilia B/epidemiologia , Hepatite C/complicações , Hepatite C/epidemiologia , Antivirais/uso terapêutico , Coinfecção , Progressão da Doença , Feminino , Seguimentos , Genótipo , Infecções por HIV , Hepacivirus , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Hepatite C Crônica/complicações , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/virologia , Humanos , Irlanda/epidemiologia , Estimativa de Kaplan-Meier , Cirrose Hepática/epidemiologia , Cirrose Hepática/etiologia , Cirrose Hepática/mortalidade , Masculino , Vigilância da População , Modelos de Riscos Proporcionais , Resultado do Tratamento , Carga Viral
13.
BMC Genomics ; 18(1): 448, 2017 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-28625162

RESUMO

BACKGROUND: Tobacco (Nicotiana tabacum) is an important plant model system that has played a key role in the early development of molecular plant biology. The tobacco genome is large and its characterisation challenging because it is an allotetraploid, likely arising from hybridisation between diploid N. sylvestris and N. tomentosiformis ancestors. A draft assembly was recently published for N. tabacum, but because of the aforementioned genome complexities it was of limited utility due to a high level of fragmentation. RESULTS: Here we report an improved tobacco genome assembly, which, aided by the application of optical mapping, achieves an N50 size of 2.17 Mb and enables anchoring of 64% of the genome to pseudomolecules; a significant increase from the previous value of 19%. We use this assembly to identify two homeologous genes that explain the differentiation of the burley tobacco market class, with potential for greater understanding of Nitrogen Utilization Efficiency and Nitrogen Use Efficiency in plants; an important trait for future sustainability of agricultural production. CONCLUSIONS: Development of an improved genome assembly for N. tabacum enables what we believe to be the first successful map-based gene discovery for the species, and demonstrates the value of an improved assembly for future research in this model and commercially-important species.


Assuntos
Loci Gênicos/genética , Genômica/normas , Nicotiana/genética , Nicotiana/metabolismo , Nitrogênio/metabolismo , Clonagem Molecular , Evolução Molecular , Genoma de Planta/genética , Padrões de Referência
14.
Dermatol Online J ; 23(6)2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28633740

RESUMO

Parvovirus B19 infections in adults are usually associated with nonspecific and mild symptoms. However, cases presenting with a lupus-like syndrome have been described, leading to the hypothesis that parvovirus infection can induce connective tissue disease. Various histopathologic features of cutaneous manifestations of parvovirus have been reported, including features which overlap with those of connective tissue disease. Herein, we discuss an unusual case of Parvovirus  B19 infection in a middle-aged woman. The biopsy results showed granulomatous vasculitis and were consistent with the previously described superantigen id reaction. This case demonstrates that infectious causes should be considered in the differential diagnosis for granulomatous vasculitis and clinicopathologic correlation is required for accurate diagnosis. We also provide a review of the literature highlighting the possible role of parvovirus in induction of a connective tissue disease-like presentation.


Assuntos
Doenças do Tecido Conjuntivo/diagnóstico , Infecções por Parvoviridae/diagnóstico , Parvovirus B19 Humano/isolamento & purificação , Biópsia , Doenças do Tecido Conjuntivo/patologia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Parvoviridae/patologia
15.
Transgenic Res ; 26(4): 567-575, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28534229

RESUMO

Swine are the only livestock species that produce both the second mammalian isoform of gonadotropin-releasing hormone (GNRH2) and its receptor (GNRHR2). Previously, we reported that GNRH2 and GNRHR2 mediate LH-independent testosterone secretion from porcine testes. To further explore this ligand-receptor complex, a pig model with reduced GNRHR2 expression was developed. Small hairpin RNA sequences targeting porcine GNRHR2 were subcloned into a lentiviral-based vector, lentiviral particles were generated and microinjected into the perivitelline space of zygotes, and embryos were transferred into a recipient. One GNRHR2 knockdown (KD) female was born that subsequently produced 80 piglets from 6 litters with 46 hemizygous progeny (57% transgenic). Hemizygous GNRHR2 KD (n = 10) and littermate control (n = 7) males were monitored at 40, 100, 150, 190, 225 and 300 days of age; body weight and testis size were measured and serum was isolated and assayed for testosterone and luteinizing hormone (LH) concentrations. Body weight of GNRHR2 KD boars was not different from littermate controls (P = 0.14), but testes were smaller (P < 0.05; 331.8 vs. 374.8 cm3, respectively). Testosterone concentrations tended (P = 0.06) to be reduced in GNRHR2 KD (1.6 ng/ml) compared to littermate control (4.2 ng/ml) males, but LH levels were similar (P = 0.47). The abundance of GNRHR2 mRNA was reduced (P < 0.001) by 69% in testicular tissue from mature GNRHR2 KD (n = 5) versus littermate control (n = 4) animals. These swine represent the first genetically-engineered model to elucidate the function of GNRH2 and its receptor in mammals.


Assuntos
Animais Geneticamente Modificados/genética , Hormônio Liberador de Gonadotropina/genética , Receptores LHRH/genética , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Feminino , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Hormônio Liberador de Gonadotropina/biossíntese , Hemizigoto , Hormônio Luteinizante/sangue , Masculino , RNA Interferente Pequeno/genética , Receptores LHRH/biossíntese , Suínos/genética , Suínos/crescimento & desenvolvimento , Testículo/crescimento & desenvolvimento , Testículo/metabolismo , Testosterona/sangue
16.
Phys Med Biol ; 61(23): N632-N641, 2016 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-27811397

RESUMO

The article aims to determine if a prospective acquisition algorithm can be used to find the ideal set of free-breathing phases for fast-helical model-based 4D-CT. A retrospective five-patient dataset that consisted of 25 repeated free breathing CT scans per patient was used. The sum of the square root amplitude difference between all the breathing phases was defined as an objective function to determine the optimality of sets of breathing phases. The objective function was intended to determine if a specific set of breathing phases would yield a motion model that could accurately predict the motion in all 25 CT scans. Voxel specific motion models were calculated using all combinations of N scans from 25 breathing trajectories, (3 ⩽ N ⩽ 25), and the minimum number of scans required to absolutely characterize the motion model was analyzed. This analysis suggests that the number of scans could potentially be reduced to as few as five scans. When the objective function was large, the resulting motion model provided an excellent approximation to the motion model created using all 25 scans.


Assuntos
Imageamento Tridimensional/métodos , Neoplasias Pulmonares/radioterapia , Movimento/fisiologia , Interpretação de Imagem Radiográfica Assistida por Computador , Tomografia Computadorizada Espiral/métodos , Algoritmos , Simulação por Computador , Humanos , Estudos Prospectivos , Respiração , Mecânica Respiratória , Estudos Retrospectivos
17.
Br J Neurosurg ; 30(4): 464-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26742681

RESUMO

The use of expensive, sophisticated, intraoperative ultrasound systems is established in cranial neurosurgery and less so in the realms of intradural spine. For units yet to acquire such costly devices, we demonstrate our experience of the readily available, anaesthetist's SonoSite™ probe in intradural spinal surgery.


Assuntos
Neurocirurgia , Procedimentos Neurocirúrgicos/instrumentação , Neoplasias da Medula Espinal/cirurgia , Coluna Vertebral/cirurgia , Anestesia , Humanos , Microcirurgia/instrumentação , Ultrassonografia/instrumentação
18.
Aust Dent J ; 61(3): 310-6, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26359636

RESUMO

BACKGROUND: There are persistent concerns about litigation in the dental and medical professions. These concerns arise in a setting where general dentists are more frequently undertaking a wider range of oral surgery procedures, potentially increasing legal risk. METHODS: Judicial cases dealing with medical negligence in the fields of general dentistry (oral surgery procedure) and oral and maxillofacial surgery were located using the three main legal databases. Relevant cases were analysed to determine the procedures involved, the patients' claims of injury, findings of negligence and damages awarded. A thematic analysis of the cases was undertaken to determine trends. RESULTS: Fifteen cases over a 20-year period were located across almost all Australian jurisdictions (eight cases involved general dentists; seven cases involved oral and maxillofacial surgeons). Eleven of the 15 cases involved determinations of whether or not the practitioner had failed in their duty of care; negligence was found in six cases. Eleven of the 15 cases related to molar extractions (eight specifically to third molar). CONCLUSIONS: Dental and medical practitioners wanting to manage legal risk should have regard to circumstances arising in judicial cases. Adequate warning of risks is critical, as is offering referral in appropriate cases. Preoperative radiographs, good medical records and processes to ensure appropriate follow-up are also important.


Assuntos
Imperícia/legislação & jurisprudência , Procedimentos Cirúrgicos Bucais/legislação & jurisprudência , Padrões de Prática Odontológica/legislação & jurisprudência , Austrália , Humanos , Padrões de Prática Odontológica/estatística & dados numéricos
19.
Clin Obes ; 5(6): 312-24, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26541244

RESUMO

The psychological and social outcomes of bariatric surgery in adolescents, together with psychological and social predictors of success, were systematically reviewed. PubMed, EMBASE, ISI Web of Science and PsychInfo were searched on July 2014. Existing data were sparse; 15 were suitable for qualitative review and six for meta-analysis (four quality of life [QOL], two depression). One study was a randomized controlled trial. A total of 139 subjects underwent Roux-en-Y gastric bypass, 202 underwent adjustable gastric band and 64 underwent sleeve gastrectomy. Overall QOL improved after bariatric surgery, regardless of surgical type with peak improvement at 6-12 months. Meta-analysis of four studies showed changed in overall QOL at latest follow-up of 2.80 standard deviation (SD) (95% confidence interval [CI] 1.23-4.37). Depression improved across all studies, regardless of procedure (effect size -0.47 SD [95% CI -0.76, -0.18] at 4-6 months). Two cohorts reported changes in both overall QOL and depression following a quadratic trajectory, with overall improvement over 2 years and deterioration in the second post-operative year. There were limited data on other psychological and social outcomes. There were insufficient data on psychosocial predictors of outcome to form evidence-based recommendations for patient selection for bariatric surgery at this time.


Assuntos
Cirurgia Bariátrica , Obesidade Infantil/psicologia , Obesidade Infantil/cirurgia , Redução de Peso , Adolescente , Medicina Baseada em Evidências , Humanos , Obesidade Mórbida/psicologia , Obesidade Mórbida/cirurgia , Qualidade de Vida/psicologia , Resultado do Tratamento
20.
Phys Med Biol ; 60(7): 3013-29, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25789418

RESUMO

The purpose of this study was to assess the feasibility of proton pencil beam scanning (PBS) for the treatment of mediastinal lymphoma. A group of 7 patients of varying tumor size (100-800 cc) were planned using a PBS anterior field. We investigated 17 fractions of 1.8 Gy(RBE) to deliver 30.6 Gy(RBE) to the internal target volume (ITV). Spots with σ ranging from 4 mm to 8 mm were used for all patients, while larger spots (σ = 6-16 mm) were employed for patients with motion perpendicular to the beam (⩾5 mm), based on initial 4-dimensional computed tomography (4D CT) motion evaluation. We considered volumetric repainting such that the same field would be delivered twice in each fraction. The ratio of extreme inhalation amplitude and regular tidal inhalation amplitude (free-breathing variability) was quantified as an indicator of potential irregular breathing during the scanning. Four-dimensional dose was calculated on the 4D CT scans based on the respiratory trace and beam delivery sequence, implemented by partitioning the spots into separate plans on each 4D CT phase. Four starting phases (end of inhalation, end of exhalation, middle of inhalation and middle of exhalation) were sampled for each painting and 4 energy switching times (0.5 s, 1 s, 3 s and 5 s) were tested, which resulted in 896 dose distributions for the analyzed cohort. Plan robustness was measured for the target and critical structures in terms of the percent difference between 'delivered' dose (4D-evaluated) and planned dose (calculated on average CT). It was found that none of the patients exhibited highly variable or chaotic breathing patterns. For all patients, the ITV D98% was degraded by <2% (standard deviations âˆ¼ 0.1%) when averaged over the whole treatment course. For six out of seven patients, the average degradation of ITV D98% per fraction was within 5% . For one patient with motion perpendicular to the beam (⩾5 mm), the degradation of ITV D98% per fraction was up to 15%, which was mitigated to 2% by employing larger spots and repainting. Deviation of mean lung dose was at most 0.2 Gy(RBE) (less than 1% of prescribed dose, 30.6 Gy(RBE)), while the deviation of heart maximum dose and cord maximum dose could exceed 5% of the prescribed dose. No significant difference in either target coverage or normal tissue dose was observed for different energy switching times compared via two-sided Wilcoxon signed-rank tests (p < 0.05). This feasibility study demonstrates that, for mediastinal lymphoma, the impact of the interplay effect on the PBS plan robustness is minimal when volumetric repainting and/or larger spots are employed.


Assuntos
Tomografia Computadorizada Quadridimensional/métodos , Linfoma/diagnóstico , Neoplasias do Mediastino/diagnóstico , Planejamento da Radioterapia Assistida por Computador/métodos , Fracionamento da Dose de Radiação , Humanos , Movimento , Respiração , Tomografia Computadorizada por Raios X/métodos
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