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1.
Nat Commun ; 11(1): 3680, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778642

RESUMO

Before acquiring highest-resolution data of Ceres, questions remained about the emplacement mechanism and source of Occator crater's bright faculae. Here we report that brine effusion emplaced the faculae in a brine-limited, impact-induced hydrothermal system. Impact-derived fracturing enabled brines to reach the surface. The central faculae, Cerealia and Pasola Facula, postdate the central pit, and were primarily sourced from an impact-induced melt chamber, with some contribution from a deeper, pre-existing brine reservoir. Vinalia Faculae, in the crater floor, were sourced from the laterally extensive deep reservoir only. Vinalia Faculae are comparatively thinner and display greater ballistic emplacement than the central faculae because the deep reservoir brines took a longer path to the surface and contained more gas than the shallower impact-induced melt chamber brines. Impact-derived fractures providing conduits, and mixing of impact-induced melt with deeper endogenic brines, could also allow oceanic material to reach the surfaces of other large icy bodies.

2.
Icarus ; 338: 113466, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32905557

RESUMO

Tidal interactions between planets or stars and the bodies that orbit them dissipate energy in their interiors. The dissipated energy heats the interior and a fraction of that energy will be released as seismic energy. Here we formalize a model to describe the tidally-driven seismic activity on planetary bodies based on tidal dissipation. To constrain the parameters of our model we use the seismic activity of the Moon, driven by tidal dissipation from the Earth-Moon interactions. We then apply this model to predict the amount of seismic energy release and largest seismic events on other moons in our Solar System and exoplanetary bodies. We find that many moons in the Solar System should be more seismically active than the Earth's Moon and many exoplanets should exhibit more seismic activity than the Earth. Finally, we examine how temporal-spatial variations in tidal dissipation manifest as variations in the locations and timing of seismic events on these bodies.

3.
Science ; 353(6303)2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27701087

RESUMO

Volcanic edifices are abundant on rocky bodies of the inner solar system. In the cold outer solar system, volcanism can occur on solid bodies with a water-ice shell, but derived cryovolcanic constructs have proved elusive. We report the discovery, using Dawn Framing Camera images, of a landform on dwarf planet Ceres that we argue represents a viscous cryovolcanic dome. Parent material of the cryomagma is a mixture of secondary minerals, including salts and water ice. Absolute model ages from impact craters reveal that extrusion of the dome has occurred recently. Ceres' evolution must have been able to sustain recent interior activity and associated surface expressions. We propose salts with low eutectic temperatures and thermal conductivities as key drivers for Ceres' long-term internal evolution.

4.
Epidemiol Infect ; 143(9): 1858-67, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25373419

RESUMO

Significant gaps in immunity to polio, measles, and rubella may exist in adults in Cambodia and threaten vaccine-preventable disease (VPD) elimination and control goals, despite high childhood vaccination coverage. We conducted a nationwide serological survey during November-December 2012 of 2154 women aged 15-39 years to assess immunity to polio, measles, and rubella and to estimate congenital rubella syndrome (CRS) incidence. Measles and rubella antibodies were detected by IgG ELISA and polio antibodies by microneutralization testing. Age-structured catalytic models were fitted to rubella serological data to predict CRS cases. Overall, 29.8% of women lacked immunity to at least one poliovirus (PV); seroprevalence to PV1, PV2 and PV3 was 85.9%, 93.4% and 83.3%, respectively. Rubella and measles antibody seroprevalence was 73.3% and 95.9%, respectively. In the 15-19 years age group, 48.2% [95% confidence interval (CI) 42.4-54.1] were susceptible to either PV1 or PV3, and 40.3% (95% CI 33.0-47.5) to rubella virus. Based on rubella antibody seroprevalence, we estimate that >600 infants are born with CRS in Cambodia annually. Significant numbers of Cambodian women are still susceptible to polio and rubella, especially those aged 15-19 years, emphasizing the need to include adults in VPD surveillance and a potential role for vaccination strategies targeted at adults.


Assuntos
Sarampo/epidemiologia , Sarampo/imunologia , Poliomielite/epidemiologia , Poliomielite/imunologia , Rubéola (Sarampo Alemão)/epidemiologia , Rubéola (Sarampo Alemão)/imunologia , Adolescente , Adulto , Fatores Etários , Anticorpos Antivirais/análise , Camboja/epidemiologia , Estudos Transversais , Suscetibilidade a Doenças/epidemiologia , Suscetibilidade a Doenças/imunologia , Suscetibilidade a Doenças/virologia , Feminino , Humanos , Incidência , Sarampo/virologia , Vírus do Sarampo/fisiologia , Poliomielite/virologia , Poliovirus/fisiologia , Prevalência , Rubéola (Sarampo Alemão)/virologia , Síndrome da Rubéola Congênita/epidemiologia , Síndrome da Rubéola Congênita/imunologia , Síndrome da Rubéola Congênita/virologia , Vírus da Rubéola/fisiologia , Estudos Soroepidemiológicos , Adulto Jovem
5.
Oncogene ; 31(30): 3525-35, 2012 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-22081069

RESUMO

The NF-κB transcription factor has a central role in diverse processes, including inflammation, proliferation and cell survival, and its activity is dysregulated in diseases such as autoimmunity and cancer. We recently identified the TRE17/ubiquitin-specific protease 6 (USP6) oncogene as the first de-ubiquitinating enzyme to activate NF-κB. TRE17/USP6 is translocated and overexpressed in aneurysmal bone cyst (ABC), a pediatric tumor characterized by extensive bone degradation and inflammatory recruitment. In the current study, we explore the mechanism by which TRE17 induces activation of NF-κB, and find that it activates the classical NF-κB pathway through an atypical mechanism that does not involve IκB degradation. TRE17 co-precipitates with IκB kinase (IKK), and IKK activity is augmented in stable cell lines overexpressing TRE17, in a USP-dependent manner. Optimal activation of NF-κB by TRE17 requires both catalytic subunits of IKK, distinguishing its mechanism from the classical and non-canonical pathways, which require either IKKß or IKKα, respectively. TRE17 stimulates phosphorylation of p65 at serine 536, a modification that has been associated with enhanced transcriptional activity and nuclear retention. Induction of S536 phosphorylation by TRE17 requires both IKKα and IKKß, as well as the IKKγ/NEMO regulatory subunit of IKK. We further demonstrate that TRE17(long) is highly tumorigenic when overexpressed in NIH3T3 fibroblasts, and that inhibition of NF-κB significantly attenuates tumor formation. In summary, these studies uncover an unexpected signaling mechanism for activation of classical NF-κB by TRE17. They further reveal a critical role for NF-κB in TRE17-mediated tumorigenesis, and suggest that NF-κB inhibitors may function as effective therapeutic agents in the treatment of ABC.


Assuntos
Transformação Celular Neoplásica/metabolismo , NF-kappa B/metabolismo , Fragmentos de Peptídeos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina Tiolesterase/metabolismo , Animais , Células HeLa , Humanos , Quinase I-kappa B/metabolismo , Camundongos , Camundongos Nus , Células NIH 3T3 , Serina/metabolismo
6.
Proc Natl Acad Sci U S A ; 104(41): 16299-304, 2007 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-17901201

RESUMO

A comprehensive analysis of both the molecular genetic and phenotypic responses of any organism to the space flight environment has never been accomplished because of significant technological and logistical hurdles. Moreover, the effects of space flight on microbial pathogenicity and associated infectious disease risks have not been studied. The bacterial pathogen Salmonella typhimurium was grown aboard Space Shuttle mission STS-115 and compared with identical ground control cultures. Global microarray and proteomic analyses revealed that 167 transcripts and 73 proteins changed expression with the conserved RNA-binding protein Hfq identified as a likely global regulator involved in the response to this environment. Hfq involvement was confirmed with a ground-based microgravity culture model. Space flight samples exhibited enhanced virulence in a murine infection model and extracellular matrix accumulation consistent with a biofilm. Strategies to target Hfq and related regulators could potentially decrease infectious disease risks during space flight missions and provide novel therapeutic options on Earth.


Assuntos
Salmonella typhimurium/genética , Salmonella typhimurium/patogenicidade , Voo Espacial , Animais , Biofilmes/crescimento & desenvolvimento , Feminino , Expressão Gênica , Genes Bacterianos , Fator Proteico 1 do Hospedeiro/fisiologia , Ferro/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Análise de Sequência com Séries de Oligonucleotídeos , Proteômica , Regulon , Salmonelose Animal/etiologia , Salmonella typhimurium/fisiologia , Virulência , Simulação de Ausência de Peso
7.
J Infect Dis ; 181 Suppl 1: S152-5, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10657207

RESUMO

A total of 226 paired nose and throat swab specimens from 113 clinical diphtheria cases from the republic of Georgia were analyzed by direct polymerase chain reaction targeting both A and B subunits of the diphtheria toxin gene, tox. Even after prolonged transport and extensive storage (7-14 months) of the clinical specimens in silica gel packages, direct polymerase chain reaction detected the diphtheria tox gene in 54% of the specimens. Specimens obtained by throat swab were three times more likely than those obtained by nose swab to be positive for Corynebacterium diphtheriae.


Assuntos
Corynebacterium diphtheriae/isolamento & purificação , Toxina Diftérica/genética , Difteria/diagnóstico , Reação em Cadeia da Polimerase/métodos , Manejo de Espécimes , Estudos de Casos e Controles , Corynebacterium diphtheriae/genética , Difteria/epidemiologia , Difteria/microbiologia , Toxina Diftérica/biossíntese , Estudos de Avaliação como Assunto , República da Geórgia/epidemiologia , Humanos , Nariz/microbiologia , Faringe/microbiologia
8.
Arch Pediatr Adolesc Med ; 153(8): 879-86, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10437765

RESUMO

BACKGROUND: Since 1995, states and jurisdictions receiving federal immunization funds have been required to perform annual measurements of vaccination coverage in their public clinics, based on data from Georgia where clinic coverage increased after the institution of a measurement and feedback intervention. OBJECTIVE: To determine if clinic vaccination coverage improved in localities that used the Georgia intervention model. DESIGN: Retrospective examination of clinic vaccination coverage data. PARTICIPANTS: Children aged 19 to 35 months enrolled in clinics in localities that had applied the intervention for 4 years or longer. INTERVENTION: The Georgia intervention model: assessment of clinic vaccination coverage, feedback of the information to the clinic, incentives to clinics, and promotion of exchange of information among clinics (AFIX). MAIN OUTCOME MEASURE: Change in median clinic coverage rates, based on the primary (4-3-1) vaccine series, with comparison to results of the National Immunization Survey. RESULTS: Four states and 2 cities that had applied the AFIX intervention for 4 years or longer were identified. The number of clinic records reviewed annually was 4639 to 18000 in 73 to 116 clinics for states, and 714 to 5276 in 8 to 25 clinics for cities. Median clinic coverage rose in all localities: Missouri, 44% (1992) to 93% (1997); Louisiana, 61% (1992) to 83% (1997); Colorado, 55% (1993) to 75% (1997); Iowa, 71% (1994) to 89% (1997); Boston, Mass, 41% (1994) to 79% (1997); and Houston, Tex, 28% (1994) to 84% (1997). The increase in clinic coverage exceeded that of the general population in 5 localities and was identical in the sixth. The average annual coverage rise attributable to the intervention was +5 percentage points per year (Georgia, +6 per year). The average crude direct program cost was $49533 per locality per year. CONCLUSION: The Georgia intervention model (AFIX) can be reproduced elsewhere and is associated with improvements in clinic vaccination coverage.


Assuntos
Programas de Imunização/estatística & dados numéricos , Revisão da Utilização de Recursos de Saúde/estatística & dados numéricos , Pré-Escolar , Retroalimentação , Georgia , Custos de Cuidados de Saúde , Pesquisas sobre Atenção à Saúde , Humanos , Lactente , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos , Recompensa , Estados Unidos
9.
J Clin Microbiol ; 36(10): 2893-9, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9738040

RESUMO

VP1 sequences were determined for poliovirus type 1 isolates obtained over a 189-day period from a poliomyelitis patient with common variable immunodeficiency syndrome (a defect in antibody formation). The isolate from the first sample, taken 11 days after onset of paralysis, contained two poliovirus populations, differing from the Sabin 1 vaccine strain by approximately 10%, differing from diverse type 1 wild polioviruses by 19 to 24%, and differing from each other by 5.5% of nucleotides. Specimens taken after day 11 appeared to contain only one major poliovirus population. Evolution of VP1 sequences at synonymous third-codon positions occurred at an overall rate of approximately 3.4% per year over the 189-day period. Assuming this rate to be constant throughout the period of infection, the infection was calculated to have started approximately 9.3 years earlier. This estimate is about the time (6. 9 years earlier) the patient received his last oral poliovirus vaccine dose, approximately 2 years before the diagnosis of immunodeficiency. These findings may have important implications for the strategy to eliminate poliovirus immunization after global polio eradication.


Assuntos
Síndromes de Imunodeficiência/complicações , Filogenia , Poliomielite/imunologia , Vacina Antipólio Oral , Poliovirus/classificação , Poliovirus/fisiologia , Adulto , Sequência de Aminoácidos , Sequência de Bases , Capsídeo/genética , Proteínas do Capsídeo , Criança , Evolução Molecular , Fezes/virologia , Seguimentos , Variação Genética , Humanos , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/virologia , Masculino , Dados de Sequência Molecular , Poliomielite/complicações , Poliomielite/virologia , Poliovirus/genética , Reação em Cadeia da Polimerase/métodos , RNA Viral/genética , RNA Viral/isolamento & purificação , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Ensaio de Placa Viral , Replicação Viral
10.
Talanta ; 42(7): 927-36, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18966313

RESUMO

A new commercial system consisting of a flow injection analysis system for hydride generation coupled with a transversely heated graphite atomizer-atomic absorption spectrometer for the determination of lead is investigated in detail. The hydride generation is optimized by using an ammonium peroxodisulphate-hydrochloric acid system as oxidant and sodium borohydride as reducing reagent. The addition of sodium cumol sulphonate as surface active substance shows advantages considering efficient plumbane production. The hydride trapping and atomization in a graphite electrothermal atomizer is also optimized. The characteristic concentration was 0.74 mug/l, the detection limit was 0.70 mug/l for 500 mul sample volumes. The relative operation standard deviation of this method was smaller than 2%. Further examinations demonstrate the influence of several heavy metals on the determination of lead. Finally, the measurement of standard reference materials shows the efficiency of the method in combination with decomposition with aqua regia solutions.

11.
Arch Ophthalmol ; 104(2): 229-32, 1986 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3947298

RESUMO

Three patients with fourth cranial nerve palsy underwent a recession of the ipsilateral inferior oblique muscle. In all three cases, the inferior oblique muscle was anteriorly displaced to the temporal border of the inferior rectus muscle. In the immediate postoperative period, all three patients developed a hypotropia and diplopia in the primary position with limitation of upgaze. The hypotropia remained stable and required retrodisplacement of the inferior oblique muscle in order to eliminate the diplopia. We emphasize the power of the anterior transposition of the inferior oblique muscle and caution its use as a unilateral procedure in patients with central fusion.


Assuntos
Músculos Oculomotores/cirurgia , Paralisia/cirurgia , Estrabismo/etiologia , Nervo Troclear , Adulto , Criança , Doenças dos Nervos Cranianos/cirurgia , Humanos , Masculino , Músculos Oculomotores/fisiopatologia , Complicações Pós-Operatórias , Reoperação , Estrabismo/fisiopatologia , Estrabismo/cirurgia
12.
Am J Phys Anthropol ; 46(2): 253-64, 1977 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-403771

RESUMO

Data obtained during a field study of two species of nonhuman primates (Alouatta villosa and Ateles geoffroyi) living in the Tikal National Park in Guatemala are used to suggest an answer to the question: To what extent is the existence of a particular form of social organization (group size, structure, and composition) an indication of the amount of energy in the form of food resources available to animals in a particular habitat? Seven researchers working in teams spent 2,318 hours in the field, 1,145 hours of which were in contact with the monkeys. Comparisons of dietary data, estimated energy expenditures, and habitat productivity provide indications of the degree to which a habitat is capable of supporting the energy and other nutritional requirements of howler and spider monkeys living within the study area. These data suggest that much larger populations and different forms of social organizations can be supported by resources available within the habitat.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Dieta , Haplorrinos , Meio Social , Alouatta , Animais , Feminino , Guatemala , Masculino , Gravidez
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