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1.
Science ; 267(5205): 1837-9, 1995 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-7892611

RESUMO

When a person attempts to produce from memory a given spatial or temporal interval, there is inevitably some error associated with the estimate. The time course of this error was measured in a series of experiments where subjects repeatedly attempted to replicate given target intervals. Sequences of the errors in both spatial and temporal replications were found to fluctuate as 1/f noises. 1/f noise is encountered in a wide variety of physical systems and is theorized to be a characteristic signature of complexity.


Assuntos
Cognição/fisiologia , Percepção Espacial/fisiologia , Percepção do Tempo/fisiologia , Análise de Fourier , Humanos , Modelos Psicológicos , Tempo de Reação/fisiologia
2.
Oncogene ; 26(50): 7158-62, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17525745

RESUMO

Endometrial carcinoma is the most common gynecological malignancy in the United States. Although most women present with early disease confined to the uterus, the majority of persistent or recurrent tumors are refractory to current chemotherapies. We have identified a total of 11 different FGFR2 mutations in 3/10 (30%) of endometrial cell lines and 19/187 (10%) of primary uterine tumors. Mutations were seen primarily in tumors of the endometrioid histologic subtype (18/115 cases investigated, 16%). The majority of the somatic mutations identified were identical to germline activating mutations in FGFR2 and FGFR3 that cause Apert Syndrome, Beare-Stevenson Syndrome, hypochondroplasia, achondroplasia and SADDAN syndrome. The two most common somatic mutations identified were S252W (in eight tumors) and N550K (in five samples). Four novel mutations were identified, three of which are also likely to result in receptor gain-of-function. Extensive functional analyses have already been performed on many of these mutations, demonstrating they result in receptor activation through a variety of mechanisms. The discovery of activating FGFR2 mutations in endometrial carcinoma raises the possibility of employing anti-FGFR molecularly targeted therapies in patients with advanced or recurrent endometrial carcinoma.


Assuntos
Doenças do Desenvolvimento Ósseo/genética , Carcinoma Endometrioide/genética , Carcinossarcoma/genética , Craniossinostoses/genética , Neoplasias do Endométrio/genética , Mutação em Linhagem Germinativa , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Idoso , Substituição de Aminoácidos/genética , Linhagem Celular Tumoral , Feminino , Humanos
3.
Res Involv Engagem ; 3: 25, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29214056

RESUMO

PLAIN ENGLISH SUMMARY: Many young adults with type 1 diabetes struggle with the day-to-day management of their condition. They often find it difficult to find the time to attend their clinic appointments and to meet with their diabetes healthcare team. Young adults living with type 1 diabetes are not routinely involved in research that may help improve health services other than being invited to take part in studies as research participants. A 3-day international conference was held in Galway in June 2016 called "Strength In Numbers: Teaming up to improve the health of young adults with type 1 diabetes". It aimed to bring together people from a broad variety of backgrounds with an interest in young adults with type 1 diabetes. Young people with type 1 diabetes came together with healthcare professionals, researchers, software developers and policy makers to come up with and agree on a new approach for engaging young adults with type 1 diabetes with their health services and to improve how they manage their diabetes.The people involved in the conference aimed to reach agreement (consensus) on a fixed set of outcome measures called a core outcome set (COS) that the group would recommend future studies involving young adults with type 1 diabetes to use, to suggest a new approach (intervention) for providing health services to young adults with type 1 diabetes, and to come up with health technology ideas that could help deliver the new intervention. Over the 3 days, this diverse international group of people that included young adults living with type 1 diabetes, agreed on a COS, 3 key parts of a new intervention and 1 possible health technology idea that could help with how the overall intervention could be delivered.Involving young adults living with type 1 diabetes in a 3-day conference along with other key groups is an effective method for coming up with a new approach to improve health services for young adults with type 1 diabetes and better support their self-management. ABSTRACT: Background A 3-day international consensus meeting was hosted by the D1 Now study team in Galway on June 22-24, 2016 called "Strength In Numbers: Teaming up to improve the health of young adults with type 1 diabetes". The aim of the meeting was to bring together young adults with type 1 diabetes, healthcare providers, policy makers and researchers to reach a consensus on strategies to improve engagement, self-management and ultimately outcomes for young adults living with type 1 diabetes. Methods This diverse stakeholder group participated in the meeting to reach consensus on (i) a core outcome set (COS) to be used in future intervention studies involving young adults with type 1 diabetes, (ii) new strategies for delivering health services to young adults and (iii) potential digital health solutions that could be incorporated into a future intervention. Results A COS of 8 outcomes and 3 key intervention components that aim to improve engagement between young adults with type 1 diabetes and service providers were identified. A digital health solution that could potentially compliment the intervention components was proposed. Conclusion The outputs from the 3-day consensus conference, that held patient and public involvement at its core, will help the research team further develop and test the D1 Now intervention for young adults with type 1 diabetes in a pilot and feasibility study and ultimately in a definitive trial. The conference represents a good example of knowledge exchange among different stakeholders for health research and service improvement.

6.
Biol Reprod ; 57(6): 1285-92, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9408232

RESUMO

The mechanism of labor initiation in humans has not been completely elucidated. Prostaglandins, estrogens, and corticotropin-releasing factor (CRF) have all been shown to affect uterine myocytes and enhance uterine contractility. There are also indications that these uterine regulators have additional effects on other sites involved in labor and that they may act in concert or, perhaps, by regulating each other. Therefore, we evaluated the CRF promoter for transcriptional regulation by prostaglandins and estrogens. Human placental choriocarcinoma cell lines were transfected with CRF-luciferase reporter genes and treated with prostaglandins. Prostaglandin E2 (PGE2), but not prostaglandin F2alpha (PGF2alpha), stimulated CRF-luciferase expression in choriocarcinoma cell lines via a cAMP-dependent pathway. A combination of transfections and in vitro binding studies tested for potential regulation of CRF by estrogen receptor (ER). ER neither regulated the CRF promoter nor interacted with steroid response half-sites from the CRF promoter. Our results provide a molecular regulatory link between PGE2 and CRF, two compounds that enhance uterine contractile function. Combined with the stimulation of prostaglandin release by CRF, these data support a potentially important "feed-forward" regulatory loop involving CRF and PGE2 in parturition. In contrast, we found no evidence for direct effects of estrogens or PGF2alpha on CRF transcription.


Assuntos
Hormônio Liberador da Corticotropina/genética , Dinoprosta/farmacologia , Dinoprostona/farmacologia , Estradiol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Placenta/química , Prostaglandinas/farmacologia , Transcrição Gênica , Animais , Linhagem Celular , Coriocarcinoma , Feminino , Haplorrinos , Humanos , Luciferases/genética , Gravidez , Proteínas Recombinantes de Fusão , Transfecção , Células Tumorais Cultivadas , Neoplasias Uterinas
7.
Genomics ; 76(1-3): 37-44, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11549315

RESUMO

Previous loss-of-heterozygosity studies in endometrial carcinoma mapped a putative tumor suppressor gene to 10q25.3-26.1. An analysis of genomic sequences for the deletion interval showed several expressed sequence tags and the homeodomain gene EMX2, a homologue of Drosophila melanogaster empty spiracles. Expression studies showed that EMX2 transcripts are abundant in the adult uterus and that message levels seem to be inversely correlated with endometrial proliferation. EMX2 RNA was more abundant in quiescent postmenopausal endometrium than in premenopausal endometrium. We found decreased EMX2 expression in a subset of primary endometrial tumors, and four of six endometrial cancer cell lines investigated failed to express EMX2. The predicted protein showed extensive amino acid conservation with EMX2 sequences from several vertebrates. There was also considerable evolutionary conservation in the 3' untranslated region. To examine the potential function of EMX2 in endometrial tumorigenesis, we investigated 20 primary tumors and 6 endometrial cancer cell lines for mutations. Two primary tumors had mutations. Inactivation or reduced expression of EMX2 in cancers, coupled with increased expression in the quiescent endometrium, indicate that this homeodomain gene is involved in maintenance of the differentiated state.


Assuntos
Sequência Conservada/genética , Neoplasias do Endométrio/genética , Genes Homeobox/genética , Proteínas de Homeodomínio/biossíntese , Proteínas de Homeodomínio/genética , Adenocarcinoma/genética , Sequência de Aminoácidos , Sequência de Bases , Análise Mutacional de DNA/métodos , DNA de Neoplasias/genética , Evolução Molecular , Feminino , Perfilação da Expressão Gênica , Genes Supressores de Tumor/genética , Humanos , Tumor Mulleriano Misto/genética , Dados de Sequência Molecular , Mutação/genética , Polimorfismo Genético/genética , Fatores de Transcrição , Células Tumorais Cultivadas
8.
J Nutr ; 113(1): 178-83, 1983 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6822887

RESUMO

Guinea pigs were maintained for various periods of time on low (0.5 mg/day), intermediate (20 mg/day), or high (100 and 500 mg/day) levels of dietary ascorbic acid. Animals in each experimental group were challenged with Candida albicans via cardiac injection, and the course of infection in the kidneys was assessed. The results show that the animals receiving only 0.5 mg of ascorbic acid per day were significantly more susceptible to the infection than animals maintained on any higher level of dietary ascorbic acid. The greater susceptibility of the guinea pigs in the 0.5-mg level group was evident, however, only during "early" stages of the infection (until about day 3). Guinea pigs receiving high levels of dietary ascorbic acid were no more resistant at any time after infection, or with any challenge dose, than those receiving an intermediate dietary level. Although these data suggest that vitamin C may be involved in resistance to candidiasis, tissue levels of ascorbic acid do not change significantly with time after infection. These results indicate that low levels of dietary ascorbic acid increase susceptibility to candidiasis, yet high (or "megadose") levels of dietary vitamin C do not show any effect on resistance to this microorganism.


Assuntos
Ácido Ascórbico/farmacologia , Candidíase/imunologia , Nefropatias/imunologia , Animais , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/metabolismo , Dieta , Relação Dose-Resposta a Droga , Relação Dose-Resposta Imunológica , Cobaias , Imunidade Inata/efeitos dos fármacos , Fatores de Tempo
9.
Arch Environ Contam Toxicol ; 8(4): 383-96, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-485207

RESUMO

Lethal and sublethal responses to the herbicides 2,4-D, DEF, propanil, and trifluralin of various life history stages of the Dungeness crab, Cancer magister, were examined to estimate maximum acceptable toxicant concentrations (MATC) of each compound for this species. Zoeae were found, in long term tests, to be the most sensitive stage. Based on the experiments with this stage, MATCs were concluded to be greater than 0.95, less than 6.9 microgram/L for DEF, greater than or equal to 26, less than 220 microgram/L for trifluralin, greater than or equal to 1,700 microgram/L for propanil, and less than 1,000 microgram/L for the free acid form of 2,4-D.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Anilidas/toxicidade , Braquiúros/efeitos dos fármacos , Herbicidas/toxicidade , Organotiofosfatos/toxicidade , Compostos Organotiofosforados/toxicidade , Propanil/toxicidade , Toluidinas/toxicidade , Trifluralina/toxicidade , Envelhecimento , Animais , Larva , Fatores de Tempo
10.
Proc Natl Acad Sci U S A ; 69(3): 561-5, 1972 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-4501573

RESUMO

A general method of imaging organic and biological surfaces based on the photoelectric effect is reported. For the experiments, a photoelectron emission microscope was constructed. It is an ultrahigh vacuum instrument using electrostatic electron lenses, microchannel plate image intensifier, cold stage, hydrogen excitation source, and magnesium fluoride optics. The organic surfaces examined were grid patterns of acridine orange, fluorescein, and benzo(a)pyrene on a Butvar surface. A biological sample, sectioned rat epididymis, was also imaged by the new photoelectron microscope. Good contrast was obtained in these initial low magnification experiments. These data demonstrate the feasibility of mapping biological surfaces according to differences in ionization potentials of exposed molecules. A number of technical difficulties, such as the intensity of the excitation source, must be solved before high resolution experiments are practical. However, it is probable that this approach can be useful, even at low magnifications, in determination of the properties of organic and biological surfaces.


Assuntos
Microscopia Eletrônica , Propriedades de Superfície , Acridinas/análise , Animais , Benzopirenos/análise , Epididimo/citologia , Fluoresceínas/análise , Fluoretos/análise , Masculino , Microscopia Eletrônica/instrumentação , Ratos
11.
J Am Chem Soc ; 88(16): 3698-702, 1966 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-5916369
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