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1.
Nature ; 589(7841): 211-213, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33442039

RESUMO

Soft γ-ray repeaters exhibit bursting emission in hard X-rays and soft γ-rays. During the active phase, they emit random short (milliseconds to several seconds long), hard-X-ray bursts, with peak luminosities1 of 1036 to 1043 erg per second. Occasionally, a giant flare with an energy of around 1044 to 1046 erg is emitted2. These phenomena are thought to arise from neutron stars with extremely high magnetic fields (1014 to 1015 gauss), called magnetars1,3,4. A portion of the second-long initial pulse of a giant flare in some respects mimics short γ-ray bursts5,6, which have recently been identified as resulting from the merger of two neutron stars accompanied by gravitational-wave emission7. Two γ-ray bursts, GRB 051103 and GRB 070201, have been associated with giant flares2,8-11. Here we report observations of the γ-ray burst GRB 200415A, which we localized to a 20-square-arcmin region of the starburst galaxy NGC 253, located about 3.5 million parsecs away. The burst had a sharp, millisecond-scale hard spectrum in the initial pulse, which was followed by steady fading and softening over 0.2 seconds. The energy released (roughly 1.3 × 1046 erg) is similar to that of the superflare5,12,13 from the Galactic soft γ-ray repeater SGR 1806-20 (roughly 2.3 × 1046 erg). We argue that GRB 200415A is a giant flare from a magnetar in NGC 253.

2.
Genet Med ; 23(11): 2087-2095, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34262154

RESUMO

PURPOSE: Ataxia-Telangiectasia Mutated (ATM) has been implicated in the risk of several cancers, but establishing a causal relationship is often challenging. Although ATM single-nucleotide polymorphisms have been linked to melanoma, few functional alleles have been identified. Therefore, ATM impact on melanoma predisposition is unclear. METHODS: From 22 American, Australian, and European sites, we collected 2,104 familial, multiple primary (MPM), and sporadic melanoma cases who underwent ATM genotyping via panel, exome, or genome sequencing, and compared the allele frequency (AF) of selected ATM variants classified as loss-of-function (LOF) and variants of uncertain significance (VUS) between this cohort and the gnomAD non-Finnish European (NFE) data set. RESULTS: LOF variants were more represented in our study cohort than in gnomAD NFE, both in all (AF = 0.005 and 0.002, OR = 2.6, 95% CI = 1.56-4.11, p < 0.01), and familial + MPM cases (AF = 0.0054 and 0.002, OR = 2.97, p < 0.01). Similarly, VUS were enriched in all (AF = 0.046 and 0.033, OR = 1.41, 95% CI = 1.6-5.09, p < 0.01) and familial + MPM cases (AF = 0.053 and 0.033, OR = 1.63, p < 0.01). In a case-control comparison of two centers that provided 1,446 controls, LOF and VUS were enriched in familial + MPM cases (p = 0.027, p = 0.018). CONCLUSION: This study, describing the largest multicenter melanoma cohort investigated for ATM germline variants, supports the role of ATM as a melanoma predisposition gene, with LOF variants suggesting a moderate-risk.


Assuntos
Ataxia Telangiectasia , Melanoma , Proteínas Mutadas de Ataxia Telangiectasia/genética , Austrália , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Melanoma/genética
3.
Br J Dermatol ; 184(6): 1085-1093, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33270213

RESUMO

BACKGROUND: Melanoma aetiology has been proposed to have two pathways, which are determined by naevi and type of sun exposure and related to the anatomical site where melanoma develops. OBJECTIVES: We examined associations with melanoma by anatomical site for a comprehensive set of risk factors including pigmentary and naevus phenotypes, ultraviolet radiation exposure and polygenic risk. METHODS: We analysed harmonized data from 2617 people with incident first invasive melanoma and 975 healthy controls recruited through two population-based case-control studies in Australia and the UK. Questionnaire data were collected by interview using a single protocol, and pathway-specific polygenic risk scores were derived from DNA samples. We estimated adjusted odds ratios using unconditional logistic regression that compared melanoma cases at each anatomical site with all controls. RESULTS: When cases were compared with control participants, there were stronger associations for many naevi vs. no naevi for melanomas on the trunk, and upper and lower limbs than on the head and neck (P-heterogeneity < 0·001). Very fair skin (vs. olive/brown skin) was more weakly related to melanoma on the trunk than to melanomas at other sites (P-heterogeneity = 0·04). There was no significant difference by anatomical site for polygenic risk. Increased weekday sun exposure was positively associated with melanoma on the head and neck but not on other sites. CONCLUSIONS: We found evidence of aetiological heterogeneity for melanoma, supporting the dual pathway hypothesis. These findings enhance understanding of risk factors for melanoma and can guide prevention and skin examination education and practices.


Assuntos
Melanoma , Neoplasias Cutâneas , Austrália/epidemiologia , Humanos , Melanoma/etiologia , Melanoma/genética , Fatores de Risco , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/genética , Raios Ultravioleta
4.
Langenbecks Arch Surg ; 406(6): 2117-2123, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33587182

RESUMO

PURPOSE: To describe the abdominal wall reconstruction technique with an Ultrapro mesh and outcome for the repair of postoperative ventral hernias after the use of a Mercedes incision during the initial abdominal operation. METHOD: A retrospective review of all the patients undergoing elective postoperative ventral hernia repair between 2013 and 2019. The cohort of these patients that had an initial Mercedes incision was used for this study. RESULTS: Fourteen patients met the criteria for this study. Thirteen of the patients were transplant patients (10 liver transplant and 3 combined pancreas and kidney transplant), and one patient was after a hepatectomy. Fifty-seven percent of these hernias were multiple defects. All the patients underwent the same repair of a modified Rives-Stoppa, transversus abdominis release, and a bilateral transverse plication. A partially absorbable Ultrapro mesh was used for all the patients, with two of the patients needing an additional Symbotex mesh in order to bridge a portion of the posterior fascia. There were 6 minor early postoperative complications (hematoma, superficial wound infection, and seroma) that did not require reoperation. Two patients were readmitted for observation of a wound hematoma, and two patients (14.2%) had recurrence during the follow-up period. The average length of hospitalization was 5.6 days. CONCLUSION: This technique, with the use of an Ultrapro mesh, was found to be safe and effective for the repair of a postoperative ventral hernia due to an initial Mercedes incision.


Assuntos
Hérnia Ventral , Hérnia Incisional , Músculos Abdominais/cirurgia , Hérnia Ventral/cirurgia , Herniorrafia , Humanos , Hérnia Incisional/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Recidiva , Estudos Retrospectivos , Telas Cirúrgicas , Resultado do Tratamento
5.
Opt Express ; 28(15): 21956-21970, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32752466

RESUMO

We present the implementation of Co2+:MgAl2O4 transparent ceramics as passive Q-switching elements in an Er:Glass laser at 1.534 µm. Linearly polarized pulsed output was obtained by Brewster angle inclination of the material Q-switching plate relative to the laser axis. Separate pulses were ∼105 ns long (FWHM), exhibiting ∼6.2 kW peak power at near TEM00 quality. Several fundamental sample properties important for laser intracavity operation were measured; thermo-optic coefficient dn/dT = ( - 3.8 ± 1) × 10-5 °C-1, thermal lensing factor L-1d(nL)/dT = 2.59 × 10-5 °C-1, linear expansion coefficient α = (3.9 ± 0.6) × 10-5 °C-1, polarizability thermal coefficient ϕ = (7.2 ± 2.2) × 10-5 °C-1, and damage threshold ∼6.5 J/cm2.

6.
Neuroimage ; 202: 116080, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31401240

RESUMO

The human mind has an automatic tendency to avoid awareness of its mortality. How this protective mechanism is implemented at the neuronal level is unknown. Here we test the hypothesis that prediction-based mechanisms mediate death-denial by shielding the self from existential threat. We provide evidence that self-specific predictive processes are downregulated during the perception of death-related linguistic stimuli and that this mechanism can predict fear-of-death. Using a magnetoencephalography visual mismatch paradigm, we show that the brain's automatic prediction response to deviancy is eliminated when death words and self-face representations are coupled, but remains present when coupled to other-face or to negative words. We further demonstrate a functional link between how death impacts self-image vs. Other-image, and show that it predicts fear-of-death. Finally, we confirm this effect in a behavioral active inference experiment showing that death-related words bias perceptual judgment on facial self and other morphed video clips. Together these results lay out, for the first time, a plausible neural-based mechanism of death-denial.


Assuntos
Atitude Frente a Morte , Encéfalo/fisiologia , Negação em Psicologia , Medo , Adulto , Viés de Atenção/fisiologia , Medo/fisiologia , Medo/psicologia , Feminino , Humanos , Magnetoencefalografia , Masculino , Autoimagem
7.
J Eur Acad Dermatol Venereol ; 33(10): 1874-1885, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31087403

RESUMO

BACKGROUND: People at high risk of developing melanoma are usually identified by pigmentary and naevus phenotypes. OBJECTIVE: We examined whether associations of these phenotypes with melanoma risk differed by ambient sun exposure or participant characteristics in two population-based, case-control studies with comparable ancestry but different ambient sun exposure. METHODS: Data were analysed from 616 cases and 496 controls from the Australian Melanoma Family Study and 2012 cases and 504 controls from the Leeds (UK) case-control study. Questionnaire, interview and dermatological skin examination data were collected using the same measurement protocols. Relative risks were estimated as odds ratios using unconditional logistic regression, adjusted for potential confounders. RESULTS: Hair and skin colour were the strongest pigmentary phenotype risk factors. All associations of pigmentary phenotype with melanoma risk were similar across countries. The median number of clinically assessed naevi was approximately three times higher in Australia than Leeds, but the relative risks for melanoma associated with each additional common or dysplastic naevus were higher for Leeds than Australia, especially for naevi on the upper and lower limbs. Higher naevus counts on the head and neck were associated with a stronger relative risk for melanoma for women than men. The two countries had similar relative risks for melanoma based on self-reported naevus density categories, but personal perceptions of naevus number differed by country. There was no consistent evidence of interactions between phenotypes on risk. CONCLUSIONS: Classifying people at high risk of melanoma based on their number of naevi should ideally take into account their country of residence, type of counts (clinical or self-reported), body site on which the naevus counts are measured and sex. The presence of naevi may be a stronger indicator of a genetic predisposition in the UK than in Australia based on less opportunity for sun exposure to influence naevus development.


Assuntos
Exposição Ambiental , Melanoma/etnologia , Nevo Pigmentado/etnologia , Neoplasias Cutâneas/etnologia , Pigmentação da Pele , Luz Solar , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Estudos de Casos e Controles , Extremidades , Feminino , Cor de Cabelo , Humanos , Masculino , Pessoa de Meia-Idade , Nevo Pigmentado/patologia , Fenótipo , Medição de Risco , Fatores de Risco , Fatores Sexuais , Neoplasias Cutâneas/patologia , Carga Tumoral , Reino Unido/epidemiologia , População Branca , Adulto Jovem
8.
J Intellect Disabil Res ; 63(6): 603-613, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30775818

RESUMO

BACKGROUND: Aquatic motor intervention has been found to be effective in reducing falls and improving verbal working memory among the general population. However, effects among older adults with intellectual disabilities (ID) have never been explored. The aim of this study was to examine the effects of aquatic motor intervention on fall risk and verbal working memory among older adults with ID. METHODS: Forty-one older adults with mild to moderate ID (age: 50-66 years) were randomly assigned to 14 weeks of aquatic motor intervention (Ai Chi: N = 19) or identical on-land motor intervention (Tai Chi: N = 22). Fall risk, measured with the Tinetti balance assessment tool (TBAT), and verbal working memory, measured with the digit span forward test, were assessed pre-intervention, after 7 weeks of intervention and post-intervention. RESULTS: Study results indicate positive effects of both aquatic and on-land motor intervention on TBAT fall risk score, while the aquatic motor intervention group improved TBAT fall risk score quicker as compared with the on-land motor intervention group. Moreover, the lower the pre-intervention TBAT score was, the higher the improvement. In addition, study findings support the positive effects of aquatic motor intervention on verbal working memory ability as measured with the digit span forward test. CONCLUSIONS: Motor intervention, and particularly in an aquatic environment, can potentially reduce fall risk. Aquatic motor intervention may help to improve verbal working memory among older adults with ID.


Assuntos
Acidentes por Quedas , Envelhecimento , Deficiência Intelectual/reabilitação , Memória de Curto Prazo , Avaliação de Resultados em Cuidados de Saúde , Medição de Risco , Tai Chi Chuan , Esportes Aquáticos , Idoso , Envelhecimento/fisiologia , Feminino , Humanos , Deficiência Intelectual/fisiopatologia , Idioma , Masculino , Memória de Curto Prazo/fisiologia , Pessoa de Meia-Idade , Esportes Aquáticos/fisiologia
9.
Pediatr Surg Int ; 35(8): 829-834, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31201486

RESUMO

Although most children with Hirschsprung disease ultimately achieve functional and comfortable stooling, some will experience a variety of problems after pull-through surgery. The most common problems include soiling, obstructive symptoms, enterocolitis, and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative soiling in children with Hirschsprung disease. The American Pediatric Surgical Association Hirschsprung Disease Interest Group engaged in a literature review and group discussions. Expert consensus was then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with soiling symptoms following pull-through for Hirschsprung disease. Causes of soiling after pull-through are broadly categorized as abnormalities in sensation, abnormalities in sphincter control, and "pseudo-incontinence." A stepwise algorithm for the diagnosis and management of soiling after a pull-through for Hirschsprung disease is presented; it is our hope that this rational approach will facilitate treatment and optimize outcomes.


Assuntos
Algoritmos , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Incontinência Fecal/cirurgia , Doença de Hirschsprung/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Guias de Prática Clínica como Assunto , Criança , Incontinência Fecal/etiologia , Doença de Hirschsprung/complicações , Humanos , Período Pós-Operatório , Resultado do Tratamento
10.
Clin Genet ; 93(6): 1254-1256, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29368331

RESUMO

Identification of a novel compound heterozygous of GNB5 in a patient with intellectual developmental disorder with cardiac arrhytmia (IDDCA), from non-consaguineous family. Three-dimensional modelling and in silico predictions suggest that GNB5 variants are causative of the phenotype, extending the number of IDDCA patients so far identified.


Assuntos
Arritmias Cardíacas/complicações , Arritmias Cardíacas/genética , Subunidades beta da Proteína de Ligação ao GTP/genética , Deficiência Intelectual/complicações , Deficiência Intelectual/genética , Mutação/genética , Sequência de Aminoácidos , Pré-Escolar , Evolução Molecular , Subunidades beta da Proteína de Ligação ao GTP/química , Heterozigoto , Humanos , Lactente , Masculino , Linhagem
11.
J Biomed Inform ; 78: 87-101, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29369797

RESUMO

We study the question of how to represent or summarize raw laboratory data taken from an electronic health record (EHR) using parametric model selection to reduce or cope with biases induced through clinical care. It has been previously demonstrated that the health care process (Hripcsak and Albers, 2012, 2013), as defined by measurement context (Hripcsak and Albers, 2013; Albers et al., 2012) and measurement patterns (Albers and Hripcsak, 2010, 2012), can influence how EHR data are distributed statistically (Kohane and Weber, 2013; Pivovarov et al., 2014). We construct an algorithm, PopKLD, which is based on information criterion model selection (Burnham and Anderson, 2002; Claeskens and Hjort, 2008), is intended to reduce and cope with health care process biases and to produce an intuitively understandable continuous summary. The PopKLD algorithm can be automated and is designed to be applicable in high-throughput settings; for example, the output of the PopKLD algorithm can be used as input for phenotyping algorithms. Moreover, we develop the PopKLD-CAT algorithm that transforms the continuous PopKLD summary into a categorical summary useful for applications that require categorical data such as topic modeling. We evaluate our methodology in two ways. First, we apply the method to laboratory data collected in two different health care contexts, primary versus intensive care. We show that the PopKLD preserves known physiologic features in the data that are lost when summarizing the data using more common laboratory data summaries such as mean and standard deviation. Second, for three disease-laboratory measurement pairs, we perform a phenotyping task: we use the PopKLD and PopKLD-CAT algorithms to define high and low values of the laboratory variable that are used for defining a disease state. We then compare the relationship between the PopKLD-CAT summary disease predictions and the same predictions using empirically estimated mean and standard deviation to a gold standard generated by clinical review of patient records. We find that the PopKLD laboratory data summary is substantially better at predicting disease state. The PopKLD or PopKLD-CAT algorithms are not meant to be used as phenotyping algorithms, but we use the phenotyping task to show what information can be gained when using a more informative laboratory data summary. In the process of evaluation our method we show that the different clinical contexts and laboratory measurements necessitate different statistical summaries. Similarly, leveraging the principle of maximum entropy we argue that while some laboratory data only have sufficient information to estimate a mean and standard deviation, other laboratory data captured in an EHR contain substantially more information than can be captured in higher-parameter models.


Assuntos
Algoritmos , Técnicas de Laboratório Clínico/estatística & dados numéricos , Mineração de Dados/métodos , Registros Eletrônicos de Saúde/estatística & dados numéricos , Ensaios de Triagem em Larga Escala/métodos , Humanos , Modelos Estatísticos , Fenótipo
12.
Indoor Air ; 28(4): 572-584, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29665159

RESUMO

Building ventilation rates and indoor airflow conditions influence occupants' exposure to indoor air pollutants. By making time- and space-resolved measurement of 3 inert tracers steadily released in a single-family house in California for 8 weeks in summer and 5 weeks in winter, this study quantifies the air change rate of the living zone with 2-hour time resolution; estimates airflow rates between the living zone, attic, and crawlspace; and characterizes mixing of air in the split-level living space. Occupant behaviors altered the air change rates, primarily through opening windows and secondarily through operating the heating system. The air change rate correlated with the number of window openings, accounting for 57% of the variability measured across 2 seasons. There were substantial upward interzonal airflows between the crawlspace, living zone, and attic; downward airflows were negligible by comparison. More than 70% of the airflow entering the living zone in the winter and at night during summer came through the crawlspace, rather than directly from outdoors. The airflow from the living zone to the attic increased with the attic-outdoor temperature difference, indicating that buoyancy associated with solar heating of the attic induced airflow from the living zone, increasing the air change rate.


Assuntos
Movimentos do Ar , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Ventilação , California , Habitação , Humanos , Estações do Ano
13.
Indoor Air ; 28(4): 559-571, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29633369

RESUMO

Residences represent an important site for bioaerosol exposure. We studied bioaerosol concentrations, emissions, and exposures in a single-family residence in northern California with 2 occupants using real-time instrumentation during 2 monitoring campaigns (8 weeks during August-October 2016 and 5 weeks during January-March 2017). Time- and size-resolved fluorescent biological aerosol particles (FBAP) and total airborne particles were measured in real time in the kitchen using an ultraviolet aerodynamic particle sizer (UVAPS). Time-resolved occupancy status, household activity data, air-change rates, and spatial distribution of size-resolved particles were also determined throughout the house. Occupant activities strongly influenced indoor FBAP levels. Indoor FBAP concentrations were an order of magnitude higher when the house was occupied than when the house was vacant. Applying an integral material-balance approach, geometric mean of total FBAP emissions from human activities observed to perturb indoor levels were in the range of 10-50 million particles per event. During the summer and winter campaigns, occupants spent an average of 10 and 8.5 hours per day, respectively, awake and at home. During these hours, the geometric mean daily-averaged FBAP exposure concentration (1-10 µm diameter) was similar for each subject at 40 particles/L for summer and 29 particles/L for winter.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Exposição Ambiental/análise , Monitoramento Ambiental , California , Fluorescência , Habitação , Humanos , Tamanho da Partícula , Material Particulado
14.
Acta Endocrinol (Buchar) ; 14(1): 142-144, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31149250

RESUMO

Parathyroid imaging modalities have been used to guide clinicians and surgeons in finding the source of hyperparathyroidism for over 40 years. Primary hyperparathyroidism (PHPT) is generally caused by a parathyroid gland(s) autonomous production of parathyroid hormone (PTH), associated by enlargement of one or more glands. Noninvasive imaging procedures that are used in the management of hyperparathyroidism are anatomical (ultrasound, computer tomography, magnetic resonance imaging) and/or functional (nuclear medicine techniques: planar scintigraphy, single photon emission tomography, positron emission imaging) and/or hybrid imaging.

15.
Environ Microbiol ; 19(8): 2964-2983, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28076891

RESUMO

Endosymbiosis of bacteria by eukaryotes is a defining feature of cellular evolution. In addition to well-known bacterial origins for mitochondria and chloroplasts, multiple origins of bacterial endosymbiosis are known within the cells of diverse animals, plants and fungi. Early-diverging lineages of terrestrial fungi harbor endosymbiotic bacteria belonging to the Burkholderiaceae. We sequenced the metagenome of the soil-inhabiting fungus Mortierella elongata and assembled the complete circular chromosome of its endosymbiont, Mycoavidus cysteinexigens, which we place within a lineage of endofungal symbionts that are sister clade to Burkholderia. The genome of M. elongata strain AG77 features a core set of primary metabolic pathways for degradation of simple carbohydrates and lipid biosynthesis, while the M. cysteinexigens (AG77) genome is reduced in size and function. Experiments using antibiotics to cure the endobacterium from the host demonstrate that the fungal host metabolism is highly modulated by presence/absence of M. cysteinexigens. Independent comparative phylogenomic analyses of fungal and bacterial genomes are consistent with an ancient origin for M. elongata - M. cysteinexigens symbiosis, most likely over 350 million years ago and concomitant with the terrestrialization of Earth and diversification of land fungi and plants.


Assuntos
Burkholderiaceae/genética , Metabolismo dos Carboidratos/genética , Genoma Bacteriano/genética , Genoma Fúngico/genética , Metabolismo dos Lipídeos/genética , Mortierella/genética , Simbiose/genética , Animais , Sequência de Bases , Burkholderiaceae/metabolismo , Burkholderiaceae/fisiologia , Evolução Molecular , Redes e Vias Metabólicas/genética , Metagenoma/genética , Mortierella/isolamento & purificação , Mortierella/fisiologia , Filogenia , Análise de Sequência de DNA
16.
Ann Oncol ; 28(9): 2086-2093, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28911061

RESUMO

The International Agency for Research on Cancer (IARC) and the US National Cancer Institute (NCI) have initiated a series of cancer-focused seminars [Scelo G, Hofmann JN, Banks RE et al. International cancer seminars: a focus on kidney cancer. Ann Oncol 2016; 27(8): 1382-1385]. In this, the second seminar, IARC and NCI convened a workshop in order to examine the state of the current science on esophageal squamous cell carcinoma etiology, genetics, early detection, treatment, and palliation, was reviewed to identify the most critical open research questions. The results of these discussions were summarized by formulating a series of 'difficult questions', which should inform and prioritize future research efforts.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Internacionalidade , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Detecção Precoce de Câncer , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago , Humanos , Fatores de Risco
17.
Faraday Discuss ; 200: 579-598, 2017 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-28574567

RESUMO

Organic compounds in the atmosphere vary widely in their molecular composition and chemical properties, so no single instrument can reasonably measure the entire range of ambient compounds. Over the past decade, a new generation of in situ, field-deployable mass spectrometers has dramatically improved our ability to detect, identify, and quantify these organic compounds, but no systematic approach has been developed to assess the extent to which currently available tools capture the entire space of chemical identity and properties that is expected in the atmosphere. Reduced-parameter frameworks that have been developed to describe atmospheric mixtures are exploited here to characterize the range of chemical properties accessed by a suite of instruments. Multiple chemical spaces (e.g. oxidation state of carbon vs. volatility, and oxygen number vs. carbon number) were populated with ions measured by several mass spectrometers, with gas- and particle-phase α-pinene oxidation products serving as the test mixture of organic compounds. Few gaps are observed in the coverage of the parameter spaces by the instruments employed in this work, though the full extent to which comprehensive measurement was achieved is difficult to assess due to uncertainty in the composition of the mixture. Overlaps between individual ions and regions in parameter space were identified, both between gas- and particle-phase measurements, and within each phase. These overlaps were conservatively found to account for little (<10%) of the measured mass. However, challenges in identifying overlaps and in accurately converting molecular formulas into chemical properties (such as volatility or reactivity) highlight a continued need to incorporate structural information into atmospheric measurements.

18.
Pediatr Surg Int ; 33(5): 523-526, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28180937

RESUMO

Although most children with Hirschsprung disease ultimately do well, many experience a variety of ongoing problems after pull-through surgery. The most common include obstructive symptoms, soiling, enterocolitis and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative obstructive symptoms in children with Hirschsprung disease. The American Pediatric Surgical Association Board of Governors established a Hirschsprung Disease Interest Group. Group discussions, literature review and expert consensus were then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with obstructive symptoms following pull-through for Hirschsprung disease. Causes of obstructive symptoms post-pull-through include mechanical obstruction; persistent or acquired aganglionosis, hypoganglionosis, or transition zone pull-through; internal sphincter achalasia; disordered motility in the proximal intestine that contains ganglion cells; or functional megacolon caused by stool-holding behavior. An algorithm for the diagnosis and management of obstructive symptoms after a pull-through for Hirschsprung disease is presented. A stepwise, logical approach to the diagnosis and management of patients experiencing obstructive symptoms following pull-through for Hirschsprung disease can facilitate treatment. Level of evidence V.


Assuntos
Doença de Hirschsprung/cirurgia , Obstrução Intestinal/diagnóstico , Obstrução Intestinal/terapia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/terapia , Toxinas Botulínicas/uso terapêutico , Criança , Pré-Escolar , Enema , Feminino , Doença de Hirschsprung/complicações , Humanos , Lactente , Obstrução Intestinal/etiologia , Masculino , Guias de Prática Clínica como Assunto
19.
Faraday Discuss ; 189: 169-89, 2016 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-27101799

RESUMO

Ozone pollution affects human health, especially in urban areas on hot sunny days. Its basic photochemistry has been known for decades and yet it is still not possible to correctly predict the high ozone levels that are the greatest threat. The CalNex_SJV study in Bakersfield CA in May/June 2010 provided an opportunity to examine ozone photochemistry in an urban area surrounded by agriculture. The measurement suite included hydroxyl (OH), hydroperoxyl (HO2), and OH reactivity, which are compared with the output of a photochemical box model. While the agreement is generally within combined uncertainties, measured HO2 far exceeds modeled HO2 in NOx-rich plumes. OH production and loss do not balance as they should in the morning, and the ozone production calculated with measured HO2 is a decade greater than that calculated with modeled HO2 when NO levels are high. Calculated ozone production using measured HO2 is twice that using modeled HO2, but this difference in calculated ozone production has minimal impact on the assessment of NOx-sensitivity or VOC-sensitivity for midday ozone production. Evidence from this study indicates that this important discrepancy is not due to the HO2 measurement or to the sampling of transported plumes but instead to either emissions of unknown organic species that accompany the NO emissions or unknown photochemistry involving nitrogen oxides and hydrogen oxides, possibly the hypothesized reaction OH + NO + O2 → HO2 + NO2.

20.
Diabetes Obes Metab ; 18(5): 519-27, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26876427

RESUMO

AIMS: To examine whether co-administration of intestinal alkaline phosphatase (IAP) with antibiotics early in life may have a preventive role against metabolic syndrome (MetS) in mice. METHODS: A total of 50 mice were allocated to four treatment groups after weaning. Mice were treated with azithromycin (AZT) ± IAP, or with no AZT ± IAP, for three intermittent 7-day cycles. After the last treatment course, the mice were administered a regular chow diet for 5 weeks and subsequently a high-fat diet for 5 weeks. Body weight, food intake, water intake, serum lipids, glucose levels and liver lipids were compared. 16S rRNA gene pyrosequencing was used to determine the differences in microbiome composition. RESULTS: Exposure to AZT early in life rendered mice susceptible to MetS in adulthood. Co-administration of IAP with AZT completely prevented this susceptibility by decreasing total body weight, serum lipids, glucose levels and liver lipids to the levels of control mice. These effects of IAP probably occur as a result of changes in the composition of specific bacterial taxa at the genus and species levels (e.g. members of Anaeroplasma and Parabacteroides). CONCLUSIONS: Co-administration of IAP with AZT early in life prevents mice from susceptibility to the later development of MetS. This effect is associated with alterations in the composition of the gut microbiota. IAP may represent a novel treatment against MetS in humans.


Assuntos
Fosfatase Alcalina/uso terapêutico , Antibacterianos/efeitos adversos , Azitromicina/efeitos adversos , Suplementos Nutricionais , Disbiose/prevenção & controle , Mucosa Intestinal/enzimologia , Síndrome Metabólica/prevenção & controle , Acholeplasma/classificação , Acholeplasma/efeitos dos fármacos , Acholeplasma/crescimento & desenvolvimento , Acholeplasma/isolamento & purificação , Fosfatase Alcalina/efeitos adversos , Animais , Bacteroides/classificação , Bacteroides/efeitos dos fármacos , Bacteroides/crescimento & desenvolvimento , Bacteroides/isolamento & purificação , Bovinos , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Disbiose/induzido quimicamente , Disbiose/microbiologia , Disbiose/fisiopatologia , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Síndrome Metabólica/complicações , Síndrome Metabólica/etiologia , Síndrome Metabólica/microbiologia , Camundongos Endogâmicos C57BL , Tipagem Molecular , Obesidade/complicações , Obesidade/etiologia , Obesidade/microbiologia , Obesidade/prevenção & controle , Desmame , Aumento de Peso/efeitos dos fármacos
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