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4.
Climacteric ; 18(5): 743-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26029989

RESUMO

OBJECTIVE: Anecdotal reports suggest that application of a cool device to the back of the neck at the onset of a hot flush can afford symptomatic relief. The effects of a novel handheld mechanical cooling device in a population of perimenopausal women with moderate-to-severe vasomotor symptoms were evaluated. METHODS: In this randomized, double-blind, sham-controlled pilot study, 40 perimenopausal women experiencing ≥ 7 moderate-to-severe hot flushes per day were recruited at a single university site. Women were randomized to the active (n = 20) or sham (n = 20) device, which was applied to the back of the neck with each hot flush over the 4-week treatment period. Hot flush scores were calculated based on frequency and severity of symptoms. The Carpenter Hot Flash Related Daily Interference Scale and Zung Anxiety Scale were used to evaluate impact on quality of life. At study end, participants completed an open-ended questionnaire to assess the degree of unblinding and overall subjective improvement in symptoms with use of the device. RESULTS: No statistically significant differences were observed between the effects of the active and sham device. However, thematic analysis of the open-ended questionnaire revealed that 12/17 women (70.6%) in the active group, compared to 4/18 (22.2%) women in the sham group felt the device provided some symptomatic relief. CONCLUSIONS: Although the majority of women using the active device acknowledged that its cooling effect afforded a degree of symptomatic relief, the symptom scores chosen for this pilot study did not reflect a beneficial effect.


Assuntos
Crioterapia/instrumentação , Fogachos/terapia , Perimenopausa , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Inquéritos e Questionários
5.
Science ; 345(6204): 1609-13, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25258079

RESUMO

The Lower to Middle Paleolithic transition (~400,000 to 200,000 years ago) is marked by technical, behavioral, and anatomical changes among hominin populations throughout Africa and Eurasia. The replacement of bifacial stone tools, such as handaxes, by tools made on flakes detached from Levallois cores documents the most important conceptual shift in stone tool production strategies since the advent of bifacial technology more than one million years earlier and has been argued to result from the expansion of archaic Homo sapiens out of Africa. Our data from Nor Geghi 1, Armenia, record the earliest synchronic use of bifacial and Levallois technology outside Africa and are consistent with the hypothesis that this transition occurred independently within geographically dispersed, technologically precocious hominin populations with a shared technological ancestry.


Assuntos
Evolução Biológica , Hominidae/anatomia & histologia , Tecnologia/história , Animais , Armênia , História Antiga , Humanos
7.
Am J Obstet Gynecol ; 205(1): 30.e1-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22088897

RESUMO

OBJECTIVE: The objective of the study was to assess women's attitudes toward 2009 US Preventive Services Task Force mammography screening guideline changes and evaluate the role of media in shaping opinions. STUDY DESIGN: Two hundred forty-nine women, aged 39-49 years, presenting for annual examinations randomized to read 1 of 2 articles, and survey completion comprised the design of the study. RESULTS: Eighty-eight percent overestimated the lifetime breast cancer (BrCa) risk. Eighty-nine percent want yearly mammograms in their 40s. Eighty-six percent felt the changes were unsafe, and even if the changes were doctor recommended, 84% would not delay screening until age 50 years. Those with a friend/relative with BrCa were more likely to want annual mammography in their forties (92% vs 77%, P = .001), and feel changes unsafe (91% vs 69%, P ≤ .0001). Participants with previous false-positive mammograms were less likely to accept doctor-recommended screening delay until age 50 years (8% vs 21%, P = .01). CONCLUSION: Women overestimate BrCa risk. Skepticism of new mammogram guidelines exists, and is increased by exposure to negative media. Those with prior false-positive mammograms are less likely to accept changes.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Mamografia/psicologia , Aceitação pelo Paciente de Cuidados de Saúde , Mulheres/psicologia , Adulto , Meios de Comunicação , Detecção Precoce de Câncer/psicologia , Reações Falso-Positivas , Feminino , Humanos , Pessoa de Meia-Idade , Risco
8.
Science ; 330(6012): 1813-5, 2010 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-21109635

RESUMO

The flyby measurements of the Cassini spacecraft at Saturn's moon Rhea reveal a tenuous oxygen (O(2))-carbon dioxide (CO(2)) atmosphere. The atmosphere appears to be sustained by chemical decomposition of the surface water ice under irradiation from Saturn's magnetospheric plasma. This in situ detection of an oxidizing atmosphere is consistent with remote observations of other icy bodies, such as Jupiter's moons Europa and Ganymede, and suggestive of a reservoir of radiolytic O(2) locked within Rhea's ice. The presence of CO(2) suggests radiolysis reactions between surface oxidants and organics or sputtering and/or outgassing of CO(2) endogenic to Rhea's ice. Observations of outflowing positive and negative ions give evidence for pickup ionization as a major atmospheric loss mechanism.


Assuntos
Dióxido de Carbono , Oxigênio , Saturno , Atmosfera , Meio Ambiente Extraterreno , Gelo , Espectrometria de Massas , Processos Fotoquímicos , Astronave
11.
Lancet ; 371(9618): 1098-107, 2008 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-18355913

RESUMO

BACKGROUND: The international standard radiotherapy schedule for early breast cancer delivers 50 Gy in 25 fractions of 2.0 Gy over 5 weeks, but there is a long history of non-standard regimens delivering a lower total dose using fewer, larger fractions (hypofractionation). We aimed to test the benefits of radiotherapy schedules using fraction sizes larger than 2.0 Gy in terms of local-regional tumour control, normal tissue responses, quality of life, and economic consequences in women prescribed post-operative radiotherapy. METHODS: Between 1999 and 2001, 2215 women with early breast cancer (pT1-3a pN0-1 M0) at 23 centres in the UK were randomly assigned after primary surgery to receive 50 Gy in 25 fractions of 2.0 Gy over 5 weeks or 40 Gy in 15 fractions of 2.67 Gy over 3 weeks. Women were eligible for the trial if they were aged over 18 years, did not have an immediate reconstruction, and were available for follow-up. Randomisation method was computer generated and was not blinded. The protocol-specified principal endpoints were local-regional tumour relapse, defined as reappearance of cancer at irradiated sites, late normal tissue effects, and quality of life. Analysis was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN59368779. FINDINGS: 1105 women were assigned to the 50 Gy group and 1110 to the 40 Gy group. After a median follow up of 6.0 years (IQR 5.0-6.2) the rate of local-regional tumour relapse at 5 years was 2.2% (95% CI 1.3-3.1) in the 40 Gy group and 3.3% (95% CI 2.2 to 4.5) in the 50 Gy group, representing an absolute difference of -0.7% (95% CI -1.7% to 0.9%)--ie, the absolute difference in local-regional relapse could be up to 1.7% better and at most 1% worse after 40 Gy than after 50 Gy. Photographic and patient self-assessments indicated lower rates of late adverse effects after 40 Gy than after 50 Gy. INTERPRETATION: A radiation schedule delivering 40 Gy in 15 fractions seems to offer rates of local-regional tumour relapse and late adverse effects at least as favourable as the standard schedule of 50 Gy in 25 fractions.


Assuntos
Neoplasias da Mama/radioterapia , Radioterapia de Alta Energia/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/cirurgia , Fracionamento da Dose de Radiação , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Modelos de Riscos Proporcionais , Qualidade de Vida , Dosagem Radioterapêutica , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Reino Unido
12.
Lancet Oncol ; 9(4): 331-41, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18356109

RESUMO

BACKGROUND: The international standard radiotherapy schedule for breast cancer treatment delivers a high total dose in 25 small daily doses (fractions). However, a lower total dose delivered in fewer, larger fractions (hypofractionation) is hypothesised to be at least as safe and effective as the standard treatment. We tested two dose levels of a 13-fraction schedule against the standard regimen with the aim of measuring the sensitivity of normal and malignant tissues to fraction size. METHODS: Between 1998 and 2002, 2236 women with early breast cancer (pT1-3a pN0-1 M0) at 17 centres in the UK were randomly assigned after primary surgery to receive 50 Gy in 25 fractions of 2.0 Gy versus 41.6 Gy or 39 Gy in 13 fractions of 3.2 Gy or 3.0 Gy over 5 weeks. Women were eligible if they were aged over 18 years, did not have an immediate surgical reconstruction, and were available for follow-up. Randomisation method was computer generated and was not blinded. The protocol-specified principal endpoints were local-regional tumour relapse, defined as reappearance of cancer at irradiated sites, late normal tissue effects, and quality of life. Analysis was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN59368779. FINDINGS: 749 women were assigned to the 50 Gy group, 750 to the 41.6 Gy group, and 737 to the 39 Gy group. After a median follow up of 5.1 years (IQR 4.4-6.0) the rate of local-regional tumour relapse at 5 years was 3.6% (95% CI 2.2-5.1) after 50 Gy, 3.5% (95% CI 2.1-4.3) after 41.6 Gy, and 5.2% (95% CI 3.5-6.9) after 39 Gy. The estimated absolute differences in 5-year local-regional relapse rates compared with 50 Gy were 0.2% (95% CI -1.3% to 2.6%) after 41.6 Gy and 0.9% (95% CI -0.8% to 3.7%) after 39 Gy. Photographic and patient self-assessments suggested lower rates of late adverse effects after 39 Gy than with 50 Gy, with an HR for late change in breast appearance (photographic) of 0.69 (95% CI 0.52-0.91, p=0.01). From a planned meta-analysis with the pilot trial, the adjusted estimates of alpha/beta value for tumour control was 4.6 Gy (95% CI 1.1-8.1) and for late change in breast appearance (photographic) was 3.4 Gy (95% CI 2.3-4.5). INTERPRETATION: The data are consistent with the hypothesis that breast cancer and the dose-limiting normal tissues respond similarly to change in radiotherapy fraction size. 41.6 Gy in 13 fractions was similar to the control regimen of 50 Gy in 25 fractions in terms of local-regional tumour control and late normal tissue effects, a result consistent with the result of START Trial B. A lower total dose in a smaller number of fractions could offer similar rates of tumour control and normal tissue damage as the international standard fractionation schedule of 50 Gy in 25 fractions.


Assuntos
Neoplasias da Mama/mortalidade , Neoplasias da Mama/radioterapia , Fracionamento da Dose de Radiação , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Intervalos de Confiança , Relação Dose-Resposta à Radiação , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Mastectomia Segmentar/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Projetos Piloto , Modelos de Riscos Proporcionais , Dosagem Radioterapêutica/normas , Radioterapia Adjuvante , Valores de Referência , Medição de Risco , Fatores Sexuais , Análise de Sobrevida , Resultado do Tratamento , Reino Unido
13.
Fungal Genet Biol ; 45(3): 338-50, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17719250

RESUMO

Candida dubliniensis and Candida albicans, the most common human fungal pathogen, have most of the same genes and high sequence similarity, but C. dubliniensis is less virulent. C. albicans causes both mucosal and hematogenously disseminated disease, C. dubliniensis mostly mucosal infections. Pulse-field electrophoresis, genomic restriction enzyme digests, Southern blotting, and the emerging sequence from the Wellcome Trust Sanger Institute were used to determine the karyotype of C. dubliniensis type strain CD36. Three chromosomes have two intact homologues. A translocation in the rDNA repeat on chromosome R exchanges telomere-proximal regions of R and chromosome 5. Translocations involving the remaining chromosomes occur at the Major Repeat Sequence. CD36 lacks an MRS on chromosome R but has one on 3. Of six other C. dubliniensis strains, no two had the same electrophoretic karyotype. Despite extensive chromosome rearrangements, karyotypic differences between C. dubliniensis and C. albicans are unlikely to affect gene expression. Karyotypic instability may account for the diminished pathogenicity of C. dubliniensis.


Assuntos
Candida albicans/genética , Candida/genética , Aberrações Cromossômicas , Cromossomos Fúngicos/genética , Southern Blotting , Antígenos CD36/genética , Candida/classificação , Candida/patogenicidade , Candida albicans/classificação , Candida albicans/patogenicidade , DNA Fúngico/genética , DNA Ribossômico/genética , Eletroforese em Gel de Campo Pulsado , Cariotipagem/métodos , Técnicas de Tipagem Micológica , Virulência
14.
Science ; 316(5826): 870-5, 2007 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-17495166

RESUMO

Titan's lower atmosphere has long been known to harbor organic aerosols (tholins) presumed to have been formed from simple molecules, such as methane and nitrogen (CH4 and N2). Up to now, it has been assumed that tholins were formed at altitudes of several hundred kilometers by processes as yet unobserved. Using measurements from a combination of mass/charge and energy/charge spectrometers on the Cassini spacecraft, we have obtained evidence for tholin formation at high altitudes (approximately 1000 kilometers) in Titan's atmosphere. The observed chemical mix strongly implies a series of chemical reactions and physical processes that lead from simple molecules (CH4 and N2) to larger, more complex molecules (80 to 350 daltons) to negatively charged massive molecules (approximately 8000 daltons), which we identify as tholins. That the process involves massive negatively charged molecules and aerosols is completely unexpected.


Assuntos
Benzeno , Hidrocarbonetos , Nitrilas , Saturno , Aerossóis , Atmosfera , Meio Ambiente Extraterreno , Íons , Peso Molecular , Fotoquímica , Astronave , Temperatura , Raios Ultravioleta
15.
Genome Biol ; 8(4): R52, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17419877

RESUMO

BACKGROUND: The 10.9x genomic sequence of Candida albicans, the most important human fungal pathogen, was published in 2004. Assembly 19 consisted of 412 supercontigs, of which 266 were a haploid set, since this fungus is diploid and contains an extensive degree of heterozygosity but lacks a complete sexual cycle. However, sequences of specific chromosomes were not determined. RESULTS: Supercontigs from Assembly 19 (183, representing 98.4% of the sequence) were assigned to individual chromosomes purified by pulse-field gel electrophoresis and hybridized to DNA microarrays. Nine Assembly 19 supercontigs were found to contain markers from two different chromosomes. Assembly 21 contains the sequence of each of the eight chromosomes and was determined using a synteny analysis with preliminary versions of the Candida dubliniensis genome assembly, bioinformatics, a sequence tagged site (STS) map of overlapping fosmid clones, and an optical map. The orientation and order of the contigs on each chromosome, repeat regions too large to be covered by a sequence run, such as the ribosomal DNA cluster and the major repeat sequence, and telomere placement were determined using the STS map. Sequence gaps were closed by PCR and sequencing of the products. The overall assembly was compared to an optical map; this identified some misassembled contigs and gave a size estimate for each chromosome. CONCLUSION: Assembly 21 reveals an ancient chromosome fusion, a number of small internal duplications followed by inversions, and a subtelomeric arrangement, including a new gene family, the TLO genes. Correlations of position with relatedness of gene families imply a novel method of dispersion. The sequence of the individual chromosomes of C. albicans raises interesting biological questions about gene family creation and dispersion, subtelomere organization, and chromosome evolution.


Assuntos
Candida albicans/genética , Cromossomos Fúngicos/química , Genoma Fúngico , Sequência de Aminoácidos , Centrômero/química , Mapeamento de Sequências Contíguas , Dados de Sequência Molecular , Fases de Leitura Aberta , Sequências Repetitivas de Ácido Nucleico , Alinhamento de Sequência , Sintenia , Proteínas de Ligação a Telômeros/química , Proteínas de Ligação a Telômeros/genética
16.
Infect Immun ; 73(11): 7366-74, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16239535

RESUMO

Candida albicans is the most common fungal pathogen of humans. The recent discovery of sexuality in this organism has led to the demonstration of a mating type locus which is usually heterozygous, although some isolates are homozygous. Tetraploids can be formed between homozygotes of the opposite mating type. However, the role of the mating process and tetraploid formation in virulence has not been investigated. We describe here experiments using a murine model of disseminated candidiasis which demonstrate that in three strains, including CAI-4, the most commonly used strain background, tetraploids are less virulent than diploids and can undergo changes in ploidy during infection. In contrast to reports with other strains, we find that MTL homozygotes are almost as virulent as the heterozygotes. These results show that the level of ploidy in Candida albicans can affect virulence, but the mating type configuration does not necessarily do so.


Assuntos
Candida albicans/genética , Candida albicans/patogenicidade , Genes Fúngicos Tipo Acasalamento/genética , Genes Fúngicos Tipo Acasalamento/fisiologia , Ploidias , Animais , Candida albicans/fisiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiologia , Genótipo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Poliploidia , Virulência/genética
17.
Clin Oncol (R Coll Radiol) ; 17(5): 343-51, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16097565

RESUMO

AIMS: To investigate intensity-modulated radiotherapy (IMRT) plans for women with carcinoma of the breast, using a small number of Sim-CT slices, thus avoiding changing the patient's position and potential problems with CT capacity. MATERIALS AND METHODS: Ten CT scans of women with breast cancer were obtained for use in the study. IMRT plans based on an open tangent pair and additional top-up segment fields were created using the full CT scan, and represented the gold standard treatment plan for comparison purposes. Five-slice CT simulator scans were artificially created by omitting intermediate slices from the full CT scans. Additionally, the intermediate CT slices were recreated via interpolation of the five slices using a standard interpolation algorithm. IMRT plans were created in the same way as for the full CT scans. To allow a suitable plan comparison to be made, the beam segments and monitor units were transferred to the full CT scans, and the dose distribution calculated. RESULTS: The interpolated five-slice plans showed no significant difference in the volume of tissue receiving dose outside the range 95-105%, compared with the IMRT plans created using the full CT data set (1.3 +/- 2.2%, P = 0.092). In contrast, the discrete slice CT simulator plans increased by 6.3 +/- 5.4%, P = 0.0054, showing a statistically significant difference in the dose distribution produced and a clinically inferior plan. CONCLUSIONS: Plans created using five discrete slice CT scans were inferior to full CT-derived IMRT treatment plans, and are therefore not acceptable for IMRT. However, interpolating five CT simulator slices provides adequate anatomical information to produce comparable IMRT plans to those created by full CT scans of the patient. This allows the introduction of IMRT for this patient group without the need to change treatment position to accommodate CT scanning.


Assuntos
Anatomia Transversal/métodos , Neoplasias da Mama/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Radioterapia/métodos , Dosagem Radioterapêutica , Radioterapia Conformacional/métodos
18.
Genetics ; 170(4): 1525-37, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15937140

RESUMO

The size of the genome in the opportunistic fungus Candida albicans is 15.6 Mb. Whole-genome shotgun sequencing was carried out at Stanford University where the sequences were assembled into 412 contigs. C. albicans is a diploid basically, and analysis of the sequence is complicated due to repeated sequences and to sequence polymorphism between homologous chromosomes. Chromosome 7 is 1 Mb in size and the best characterized of the 8 chromosomes in C. albicans. We assigned 16 of the contigs, ranging in length from 7309 to 267,590 bp, to chromosome 7 and determined sequences of 16 regions. These regions included four gaps, a misassembled sequence, and two major repeat sequences (MRS) of >16 kb. The length of the continuous sequence attained was 949,626 bp and provided complete coverage of chromosome 7 except for telomeric regions. Sequence analysis was carried out and predicted 404 genes, 11 of which included at least one intron. A 7-kb indel, which might be caused by a retrotransposon, was identified as the largest difference between the homologous chromosomes. Synteny analysis revealed that the degree of synteny between C. albicans and Saccharomyces cerevisiae is too weak to use for completion of the genomic sequence in C. albicans.


Assuntos
Candida albicans/genética , Cromossomos Fúngicos , Genoma Fúngico , Mapeamento Físico do Cromossomo , Saccharomyces cerevisiae/genética , Sintenia , Sequência de Aminoácidos , Pareamento de Bases , Sequência de Bases , DNA Fúngico , Ligação Genética , Íntrons , Dados de Sequência Molecular , Técnicas de Amplificação de Ácido Nucleico , Fases de Leitura Aberta , Análise de Sequência de DNA
19.
J Reprod Med ; 49(10): 812-6, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15568405

RESUMO

OBJECTIVE: To determine the percentage of very-low-birth-weight (VLBW) infants (<1500 g) and infant deaths attributable to multiple births in the general population and in women aged 35+. STUDY DESIGN: The year 2000 Massachusetts birth certificate database with linked births-deaths was examined. Etiologic fractions (EF) for VLBW and infant mortality attributable to multiples were calculated for the general population and the 35+ age group. The percentages of multiples occurring in the 35+ age group were calculated. Infant deaths due to congenital anomalies and "perinatal conditions" were calculated. RESULTS: There were 81,582 resident births in Massachusetts in 2000. Of them 4.3% were multiples. Of the 1090 VLBW infants, 26.1% (95% CI: 23.5-28.8) were in twins and 7.7% (95% CI: 6.2-9.5) in higher-order multiples, yielding an EF of 30.8% for multiples in VLBW. In the 35+ age group, the multiple birth ratio was 6.6% (95% CI: 6.3-7.0). The EF for multiples and VLBW in this age group was 33.7%. The 35+ age group accounted for 32.4% (95% CI: 30.8-34.0) of twins and 45.5% (95% CI: 39.1-52.0) of higher-order multiples born in 2000. Of the 392 infant deaths, 57 (14.6%; 95% CI: 11.2-18.4) were attributed to congenital anomalies, and 236 (60.2%; 95% CI: 55.2-65.0) to "perinatal conditions." Multiples were responsible for 8 (14%; 95% CI: 6.3-25.8) of deaths due to anomalies, and 73 (30.9%; 95% CI: 25.1-37.3) due to "perinatal conditions." CONCLUSION: Over 30% of VLBW infants, nearly 20% of infant mortality and >30% of infant mortality due to perinatal conditions could be attributed to multiples. Multiple pregnancy is a significant public health problem.


Assuntos
Causas de Morte , Mortalidade Infantil/tendências , Recém-Nascido de muito Baixo Peso , Prole de Múltiplos Nascimentos/estatística & dados numéricos , Adulto , Declaração de Nascimento , Intervalos de Confiança , Feminino , Humanos , Incidência , Recém-Nascido , Massachusetts/epidemiologia , Idade Materna , Análise Multivariada , Gravidez , Cuidado Pré-Natal , Saúde Pública , Sistema de Registros , Medição de Risco
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