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2.
Cereb Cortex ; 26(3): 1309-1321, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26656998

RESUMO

Crying is the most salient vocal signal of distress. The cries of a newborn infant alert adult listeners and often elicit caregiving behavior. For the parent, rapid responding to an infant in distress is an adaptive behavior, functioning to ensure offspring survival. The ability to react rapidly requires quick recognition and evaluation of stimuli followed by a co-ordinated motor response. Previous neuroimaging research has demonstrated early specialized activity in response to infant faces. Using magnetoencephalography, we found similarly early (100-200 ms) differences in neural responses to infant and adult cry vocalizations in auditory, emotional, and motor cortical brain regions. We propose that this early differential activity may help to rapidly identify infant cries and engage affective and motor neural circuitry to promote adaptive behavioral responding, before conscious awareness. These differences were observed in adults who were not parents, perhaps indicative of a universal brain-based "caregiving instinct."


Assuntos
Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Cuidadores , Reconhecimento Fisiológico de Modelo/fisiologia , Estimulação Acústica , Adulto , Conscientização/fisiologia , Cuidadores/psicologia , Choro/psicologia , Potenciais Evocados , Feminino , Humanos , Lactente , Magnetoencefalografia , Masculino , Testes Neuropsicológicos , Tempo , Adulto Jovem
3.
Int J Legal Med ; 128(4): 685-98, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24553729

RESUMO

A review of information that can be provided from measurements made on natural and anthropogenic radionuclide activities in human skeletal remains has been undertaken to establish what reliable information of forensic anthropological use can be obtained regarding years of birth and death (and hence post-mortem interval (PMI)). Of the anthropogenic radionuclides that have entered the environment, radiocarbon ((14)C) can currently be used to generate the most useful and reliable information. Measurements on single bones can indicate whether or not the person died during the nuclear era, while recent research suggests that measurements on trabecular bone may, depending on the chronological age of the remains, provide estimates of year of death and hence PMI. Additionally, (14)C measurements made on different components of single teeth or on teeth formed at different times can provide estimates of year of birth to within 1-2 years of the true year. Of the other anthropogenic radionuclides, (90)Sr shows some promise but there are problems of (1) variations in activities between individuals, (2) relatively large analytical uncertainties and (3) diagenetic contamination. With respect to natural series radionuclides, it is concluded that there is no convincing evidence that (210)Pb dating can be used in a rigorous, quantitative fashion to establish a PMI. Similarly, for daughter/parent pairs such as (210)Po/(210)Pb (from the (238)U decay series) and (228)Th/(228)Ra (from the (232)Th decay series), the combination of analytical uncertainty and uncertainty in activity ratios at the point of death inevitably results in major uncertainty in any estimate of PMI. However, observation of the disequilibrium between these two daughter/parent pairs could potentially be used in a qualitative way to support other forensic evidence.


Assuntos
Osso e Ossos/química , Mudanças Depois da Morte , Radioisótopos/análise , Dente/química , Radioisótopos de Carbono/análise , Ciências Forenses , Meia-Vida , Humanos , Chumbo/análise , Armas Nucleares , Polônio/análise , Rádio (Elemento)/análise , Tório/análise , Urânio/análise
4.
Sci Total Environ ; 409(10): 1854-66, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21345483

RESUMO

Uranium associations with colloidal and truly dissolved soil porewater components from two Ministry of Defence Firing Ranges in the UK were investigated. Porewater samples from 2-cm depth intervals for three soil cores from each of the Dundrennan and Eskmeals ranges were fractionated using centrifugal ultrafiltration (UF) and gel electrophoresis (GE). Soil porewaters from a transect running downslope from the Dundrennan firing area towards a stream (Dunrod Burn) were examined similarly. Uranium concentrations and isotopic composition were determined using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Multi-Collector-Inductively Coupled Plasma-Mass Spectrometry (MC-ICP-MS), respectively. The soils at Dundrennan were Fe- and Al-rich clay-loam soils whilst at Eskmeals, they were Fe- and Al-poor sandy soils; both, however, had similar organic matter contents due to the presence of a near-surface peaty layer at Eskmeals. These compositional features influenced the porewater composition and indeed the associations of U (and DU). In general, at Dundrennan, U was split between large (100kDa-0.2µm) and small (3-30kDa) organic colloids whilst at Eskmeals, U was mainly in the small colloidal and truly dissolved fractions. Especially below 10cm depth, association with large Fe/Al/organic colloids was considered to be a precursor to the removal of U from the Dundrennan porewaters to the solid phase. In contrast, the association of U with small organic colloids was largely responsible for inhibiting attenuation in the Eskmeals soils. Lateral migration of U (and DU) through near-surface Dundrennan soils will involve both large and small colloids but, at depth, transport of the smaller amounts of U remaining in the porewaters may involve large colloids only. For one of the Dundrennan cores the importance of redox-related processes for the re-mobilisation of DU was also indicated as Mn(IV) reduction resulted in the release of both Mn(II) and U(VI) into the truly dissolved phase.


Assuntos
Água Doce/química , Poluentes do Solo/análise , Urânio/análise , Poluentes Químicos da Água/análise , Armas , Reino Unido , Movimentos da Água
5.
Sci Total Environ ; 407(21): 5578-88, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19646736

RESUMO

The historical accumulation rates of mercury resulting from atmospheric deposition to four Scottish ombrotrophic peat bogs, Turclossie Moss (northeast Scotland), Flanders Moss (west-central), Red Moss of Balerno (east-central) and Carsegowan Moss (southwest), were determined via analysis of (210)Pb- and (14)C-dated cores up to 2000 years old. Average pre-industrial rates of mercury accumulation of 4.5 and 3.7 microg m(-2) y(-1) were obtained for Flanders Moss (A.D. 1-1800) and Red Moss of Balerno (A.D. 800-1800), respectively. Thereafter, mercury accumulation rates increased to typical maximum values of 51, 61, 77 and 85 microg m(-2) y(-1), recorded at different times possibly reflecting local/regional influences during the first 70 years of the 20th century, at the four sites (TM, FM, RM, CM), before declining to a mean value of 27+/-15 microg m(-2) y(-1) during the late 1990s/early 2000s. Comparison of such trends for mercury with those for lead and arsenic in the cores and also with direct data for the declining UK emissions of these three elements since 1970 suggested that a substantial proportion of the mercury deposited at these sites over the past few decades originated from outwith the UK, with contributions to wet and dry deposition arising from long-range transport of mercury released by sources such as combustion of coal. Confidence in the chronological reliability of these core-derived trends in absolute and relative accumulation of mercury, at least since the 19th century, was provided by the excellent agreement between the corresponding detailed and characteristic temporal trends in the (206)Pb/(207)Pb isotopic ratio of lead in the (210)Pb-dated Turclossie Moss core and those in archival Scottish Sphagnum moss samples of known date of collection. The possibility of some longer-term loss of volatile mercury released from diagenetically altered older peat cannot, however, be excluded by the findings of this study.


Assuntos
Poluentes Ambientais/análise , Poluição Ambiental/história , Mercúrio/análise , Áreas Alagadas , Radioisótopos de Carbono , Monitoramento Ambiental , Sedimentos Geológicos/química , Meia-Vida , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , História Antiga , História Medieval , Radioisótopos de Chumbo , Datação Radiométrica , Escócia , Solo
6.
Environ Sci Technol ; 42(24): 9158-64, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19174886

RESUMO

The mobility and bioavailability of depleted uranium (DU) in soils at a UK Ministry of Defence (UK MoD) weapons testing range were investigated. Soil and vegetation were collected near a test-firing position and at eight points along a transect line extending approximately 200 m down-slope, perpendicular to the firing line, toward a small stream. Earthworms and porewaters were subsequently separated from the soils and both total filtered porewater (<0.2 microm) and discrete size fractions (0.2 microm-100 kDa, 100-30 kDa, 30-3 kDa, and <3 kDa)obtainedvia centrifugal ultrafiltration were examined. Uranium concentrations were determined by inductively coupled plasma optical emission spectrometry (ICP-OES) for soils and ICP-mass spectrometry (MS) for earthworms and porewaters, while 235U:238U atom ratios were determined by multicollector (MC)-ICP-MS. Comparison of the porewater and earthworm isotopic values with those of the soil solids indicated that DU released into the environment during weapons test-firing operations was more labile and more bioavailable than naturally occurring U in the soils at the testing range. Importantly, DU was shown to be present in soil porewater even at a distance of approximately 185 m from the test-firing position and, along the extent of the transect was apparently associated with organic colloids.


Assuntos
Monitoramento Ambiental , Oligoquetos/química , Solo , Urânio/análise , Água/química , Armas , Animais , Geografia , Isótopos , Compostos Orgânicos/análise , Tamanho da Partícula , Plantas/química , Porosidade , Reino Unido
7.
Colorectal Dis ; 10(4): 344-51, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17949449

RESUMO

OBJECTIVE: Identification of biological markers that may predict response to chemotherapy would allow the individualization of treatment by enabling selection of patients most likely to benefit from chemotherapy. The aims of this study were to determine whether p53 mutation status and p53 and p33(ING1b) protein expression can predict which patients with Dukes' C colorectal cancer following curative surgical resection respond to adjuvant chemotherapy with 5-fluorouracil (5-FU). METHOD: Patients with Dukes'C colorectal cancer (n = 41) were studied. DNA was extracted and analysed for p53 mutation using PCR-based direct DNA sequencing. Tumours were analysed for p53 protein expression by immunohistochemistry using DO-7 monoclonal antibody and for p33(ING1b) protein expression using GN1 monoclonal antibody. RESULTS: There was a significant association between p53 mutation status analysed by gene sequencing and overall and metastasis-free survival (P = 0.03 and 0.004, respectively, log-rank test). By contrast, no significant correlation was found between p53 and p33(ING1b) protein expression and overall or metastasis-free survival. CONCLUSION: In patients with Dukes'C colorectal cancer who underwent curative surgical resection of the primary tumour, followed by 5-FU-based adjuvant chemotherapy, p53 mutation status as assessed by gene sequencing is a significant predictor of overall and metastasis-free survival.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Nucleares/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adulto , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Quimioterapia Adjuvante/métodos , Estudos de Coortes , Neoplasias Colorretais/classificação , Neoplasias Colorretais/cirurgia , Intervalo Livre de Doença , Feminino , Fluoruracila/uso terapêutico , Humanos , Proteína 1 Inibidora do Crescimento , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mutação/genética , Valor Preditivo dos Testes
8.
J Environ Monit ; 9(7): 740-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17607395

RESUMO

Depleted uranium (DU) weapons testing programmes have been conducted at two locations within the UK. An investigation was therefore carried out to assess the extent of any environmental contamination arising from these test programmes using both alpha spectrometry and mass spectrometry techniques. Uranium isotopic signatures indicative of DU contamination were observed in soil, plant and earthworm samples collected in the immediate vicinity of test firing points and targets, but contamination was found to be localised to these areas. This paper demonstrates the superiority of the (235)U : (238)U ratio over the (234)U : (238)U ratio for identifying and quantifying DU contamination in environmental samples, and also describes the respective circumstances under which alpha spectrometry or mass spectrometry may be the more appropriate analytical tool.


Assuntos
Oligoquetos/metabolismo , Plantas/metabolismo , Poluentes Radioativos do Solo/análise , Urânio/análise , Animais , Inglaterra , Guerra Nuclear , Monitoramento de Radiação/métodos , Escócia , Poluentes Radioativos do Solo/metabolismo , Urânio/metabolismo
9.
J Environ Monit ; 7(12): 1137-47, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16307064

RESUMO

Two cores collected in 2001 and 2004 from Flanders Moss ombrotrophic peat bog in central Scotland were dated (14C, 210Pb) and analysed (ICP-OES, ICP-MS) to derive and compare the historical atmospheric deposition records of Sb and Pb over the past 2500 years. After correction, via Sc, for contributions from soil dust, depositional fluxes of Sb and Pb peaked from ca. 1920-1960 A.D., with >95% of the anthropogenic inventories deposited post-1800 A.D. Over the past two centuries, trends in Sb and Pb deposition have been broadly similar, with fluctuations in the anthropogenic Sb/Pb ratio reflecting temporal variations in the relative input from emission sources such as the mining and smelting of Pb ores (in which Sb is commonly present, as at Leadhills/Wanlockhead in southern Scotland), combustion of coal (for which the Sb/Pb ratio is approximately an order of magnitude greater than in Pb ores) and exhaust emissions (Pb from leaded petrol) and abrasion products from the brake linings (Sb from heat-resistant Sb compounds) of automobiles. The influence of leaded petrol has been most noticeable in recent decades, firstly through the resultant minima in Sb/Pb and 206Pb/207Pb ratios (the latter arising from the use of less radiogenic Australian Pb in alkylPb additives) and then, during its phasing out and the adoption of unleaded petrol, complete by 2000 A.D., the subsequent increase in both Sb/Pb and 206Pb/207Pb ratios. The extent of the 20th century maximum anthropogenic enrichment of Sb and Pb, relative to the natural Sc-normalised levels of the Upper Continental Crust, was similar at approximately 50- to 100-fold. Prior to 1800 A.D., the influence of metallurgical activities on Sb and Pb concentrations in the peat cores during both the Mediaeval and Roman/pre-Roman periods was discernible, small Sb and Pb peaks during the latter appearing attributable, on the basis of Pb isotopic composition, to the mining/smelting of Pb ores indigenous to Britain.


Assuntos
Antimônio/análise , Chumbo/análise , Poluentes do Solo/análise , Poluentes do Solo/história , Antimônio/história , Automóveis , Radioisótopos de Carbono/análise , Monitoramento Ambiental , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , História Antiga , História Medieval , Chumbo/história , Radioisótopos de Chumbo/análise , Metalurgia , Mineração , Centrais Elétricas , Escócia , Solo/análise
10.
J Infect Dis ; 182(2): 629-33, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10915102

RESUMO

Studies were conducted to determine how malaria parasites are cleared from the blood after antimalarial treatment. Neither artesunate nor quinine decreased parasitized red cell deformability or increased antibody binding. In acute falciparum malaria, ring-infected erythrocyte surface antigen (RESA) was observed in erythrocytes without malaria parasites (RESA-red blood cell [RBC]), indicating prior parasitization. In uncomplicated malaria, RESA-RBC numbers increased significantly (P=.002) within 24 h of starting artesunate but rose much more slowly (7 days) after quinine treatment. In severe malaria, RESA-RBC increased significantly (P=. 001) within hours of starting artesunate but not with quinine treatment (P=.43). RESA-RBCs were not produced after drug treatment of malaria parasite cultures in vitro. Rapid malaria parasite clearance after treatment with artemisinin derivatives results mainly from the extraction of drug-affected parasites from host erythrocytes-presumably by the spleen. This explains why the fall in hematocrit after treatment of hyperparasitemia is often less than that predicted from loss of parasitized cells.


Assuntos
Artemisininas , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Parasitemia/tratamento farmacológico , Quinina/uso terapêutico , Sesquiterpenos/uso terapêutico , Animais , Antimaláricos/uso terapêutico , Artesunato , Eritrócitos/parasitologia , Humanos , Plasmodium falciparum/citologia
11.
Clin Infect Dis ; 29(2): 375-80, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10476745

RESUMO

A prospective, open, randomized, comparative treatment trial was conducted to compare the therapeutic efficacy of the conventional four-drug combination (chloramphenicol, trimethoprim-sulfamethoxazole, and doxycycline) with that of doxycycline alone in oral maintenance treatment of melioidosis. Adult Thai patients with culture-confirmed melioidosis were randomized to receive treatment with either regimen for a minimum of 12 weeks, usually following intravenous treatment of severe disease. The main outcome measure was culture-confirmed relapse. One hundred sixteen patients were enrolled; 109 had culture-confirmed melioidosis, and 87 were considered evaluable (43 had received doxycycline). Culture-confirmed relapse occurred in one patient randomized to the conventional regimen and in 11 (25.6%) randomized to the doxycycline regimen (P = .009), and treatment failed for 8 (18.2%) versus 20 (46.5%), respectively (P = .009). Adverse effects occurred in 26% of patients overall. Doxycycline alone cannot be recommended for a first-line regimen of oral maintenance treatment of melioidosis.


Assuntos
Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Cloranfenicol/uso terapêutico , Doxiciclina/uso terapêutico , Quimioterapia Combinada/uso terapêutico , Melioidose/tratamento farmacológico , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Adolescente , Adulto , Idoso , Antibacterianos/efeitos adversos , Anti-Infecciosos/efeitos adversos , Cloranfenicol/efeitos adversos , Doxiciclina/efeitos adversos , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Falha de Tratamento , Resultado do Tratamento , Combinação Trimetoprima e Sulfametoxazol/efeitos adversos
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