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2.
Anat Rec (Hoboken) ; 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37877628

RESUMO

The zygomatic root, along with other key craniofacial features, is hypothesized to play a crucial role in strengthening the face in response to stresses and strains related to feeding. As such, it has been cited as indicative of dietary specialization among fossil taxa, although it remains unknown how variable zygomatic arch root position is among living primates, and whether its positioning predicts differences in diet. We test whether primates that consume more mechanically challenging foods possess more anteriorly positioned zygomatic roots compared to those consuming less challenging foods. Zygomatic root position, as defined by the zygomaxillare landmark, was identified and recorded from digital images and physical specimens of adult primate crania. Data were collected from 33 haplorhine species (n = 722). Published data were used to assign species to a dietary type based on patterns of overall consumption along with reliance on especially challenging foods. Pairwise comparisons between mechanically challenging (hard and/or tough) and less mechanically challenging (soft) consumers found significant differences (p < 0.05) in the position of the zygomatic root in 17 of 20 pairs, 11 of which supported the prediction that a more mechanically challenging diet is associated with a more anteriorly placed zygomatic root. PGLS analysis found no significant effect of phylogeny on root position. This suggests that a more anteriorly positioned zygomatic root is useful for identifying dietary specialization in some taxa but is not required for consuming a mechanically challenging diet given that other craniofacial and behavioral factors can facilitate the consumption of such foods.

4.
Sci Total Environ ; 858(Pt 1): 159664, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306832

RESUMO

The rewetting of degraded peatlands has been adopted as a method to address climate change. Concerns have been raised about the effects of peat inundation and drying cycles, in more extreme climate events, on the potential release of nitrogen (N) species, in particular ammonium (NH4-N), once rewetted, as well as the physico-chemical and biological properties of the peat. This study used intact peat cores to measure the impact of two different cycles of peat inundation and drying (1 month and 2 month) over a total study duration of 56 weeks on the (1) NH4-N, nitrate-N (NO3-N) and dissolved reactive phosphorus (DRP) in the soil pore water; (2) microbial community structure; (3) physico-chemical properties of the peat; and (4) the structure of the peat, and therefore its ability to mitigate flood risks and storm surges. The study found that rewetted cores released NO3-N in the pore water up to a concentration of 6.25 mg L-1, but had no appreciable impact on NH4-N, which remained below 1.7 mg L-1 over the study duration. DRP moved quickly though the upper layers of the cores, but physico-chemical analysis suggested it was adsorbed to more iron-rich soil, which was present at depths below 0.4 m in the cores. Time intervals between inundation produced no significant difference on the forms of inorganic N released, nor did it compact the soil or change the microbial community structure. The depth of the water table, however, had a significant impact on inorganic N release, particularly NO3-N, which indicates that this N species, and not NH4-N, may be problematic in rewetted peatlands.


Assuntos
Nitrogênio , Solo , Solo/química , Nitrogênio/análise , Fósforo/análise , Nitratos/análise , Água/química
5.
BJOG ; 128(8): 1282-1291, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33539617

RESUMO

OBJECTIVE: To study genetic variants and their function within genes coding for complement receptors in pre-eclampsia. DESIGN: A case-control study. SETTING: Pre-eclampsia is a common vascular disease of pregnancy. The clearance of placenta-derived material is one of the functions of the complement system in pregnancy. POPULATION: We genotyped 500 women with pre-eclamptic pregnancies and 190 pregnant women without pre-eclampsia, as controls, from the FINNPEC cohort, and 122 women with pre-eclamptic pregnancies and 1905 controls from the national FINRISK cohort. METHODS: The functional consequences of genotypes discovered by targeted exomic sequencing were explored by analysing the binding of the main ligand iC3b to mutated CR3 or CR4, which were transiently expressed on the surface of COS-1 cells. MAIN OUTCOME MEASURES: Allele frequencies were compared between pre-eclamptic pregnancies and controls in genetic studies. The functional consequences of selected variants were measured by binding assays. RESULTS: The most significantly pre-eclampsia-linked CR3 variant M441K (P = 4.27E-4, OR = 1.401, 95% CI = 1.167-1.682) displayed a trend of increased adhesion to iC3b (P = 0.051). The CR4 variant A251T was found to enhance the adhesion of CR4 to iC3b, whereas W48R resulted in a decrease of the binding of CR4 to iC3b. CONCLUSIONS: Results suggest that changes in complement-facilitated phagocytosis are associated with pre-eclampsia. Further studies are needed to ascertain whether aberrant CR3 and CR4 activity leads to altered pro- and anti-inflammatory cytokine responses in individuals carrying the associated variants, and the role of these receptors in pre-eclampsia pathogenesis. TWEETABLE ABSTRACT: Genetic variants of complement receptors CR3 and CR4 have functional consequences that are associated with pre-eclampsia.


Assuntos
Antígeno CD11b/genética , Integrina alfaXbeta2/genética , Antígeno de Macrófago 1/genética , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/imunologia , Antígenos CD18/metabolismo , Citocinas/biossíntese , Feminino , Genótipo , Humanos , Integrina alfaXbeta2/metabolismo , Antígeno de Macrófago 1/metabolismo , Mutação , Fagocitose , Gravidez
6.
J Prev Alzheimers Dis ; 8(1): 29-32, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33336221

RESUMO

Emerging evidence of brain injury on risk of neurodegenerative diseases such as Alzheimer's disease (AD) and chronic traumatic encephalopathy (CTE) have resulted in interest in therapeutic potential of omega-3 fatty acids (n-3FA). We conducted a systematic review of n-3FA therapeutic efficacy for ageing adults at risk of AD/CTE following a history of repeated head trauma. Databases for articles between 1980-June 2020 were examined for studies reporting on n-3 FAs in adults (≥ 45 years) with a history of repeated brain injury. Following an initial screen of 175 articles, 12 studies were considered but were eventually rejected, as they did not meet inclusion criteria. Our review could find no evidence to support, or disprove, effectiveness of n-3FA intervention in older adults with a history of head trauma. With animal studies showing neuro-restorative potential of n-3FA following brain injury, this review highlights the urgent need for human research in this area.


Assuntos
Doença de Alzheimer/prevenção & controle , Encefalopatia Traumática Crônica/prevenção & controle , Ácidos Graxos Ômega-3/uso terapêutico , Envelhecimento , Doença de Alzheimer/etiologia , Animais , Concussão Encefálica/complicações , Encefalopatia Traumática Crônica/etiologia , Humanos , Recidiva
7.
Sci Rep ; 10(1): 18845, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33139857

RESUMO

22q11.2 Deletion Syndrome (22q11.2DS) is the most common microdeletion in humans, with a heterogenous clinical presentation including medical, behavioural and psychiatric conditions. Previous neuroimaging studies examining the neuroanatomical underpinnings of 22q11.2DS show alterations in cortical volume (CV), cortical thickness (CT) and surface area (SA). The aim of this study was to identify (1) the spatially distributed networks of differences in CT and SA in 22q11.2DS compared to controls, (2) their unique and spatial overlap, as well as (3) their relative contribution to observed differences in CV. Structural MRI scans were obtained from 62 individuals with 22q11.2DS and 57 age-and-gender-matched controls (aged 6-31). Using FreeSurfer, we examined differences in vertex-wise estimates of CV, CT and SA at each vertex, and compared the frequencies of vertices with a unique or overlapping difference for each morphometric feature. Our findings indicate that CT and SA make both common and unique contributions to volumetric differences in 22q11.2DS, and in some areas, their strong opposite effects mask differences in CV. By identifying the neuroanatomic variability in 22q11.2DS, and the separate contributions of CT and SA, we can start exploring the shared and distinct mechanisms that mediate neuropsychiatric symptoms across disorders, e.g. 22q11.2DS-related ASD and/or psychosis/schizophrenia.


Assuntos
Espessura Cortical do Cérebro , Encéfalo/fisiopatologia , Síndrome de DiGeorge/fisiopatologia , Esquizofrenia/fisiopatologia , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Criança , Síndrome de DiGeorge/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Escalas de Graduação Psiquiátrica , Esquizofrenia/diagnóstico por imagem , Propriedades de Superfície , Adulto Jovem
8.
J Psychiatr Res ; 111: 68-73, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30685564

RESUMO

Functional unblinding due to treatment emergent adverse events (TEAEs) may occur with any investigational drug and poses a challenge for double-blind, placebo-controlled studies. This pilot study compared site-based Montgomery-Asberg Depression Rating Scale (MADRS) scores to remote, site-independent scores by blinded raters. Audio-digital recordings of site-based MADRS interviews were obtained from a subset of patients during a double-blind, placebo-controlled study of esketamine nasal spray or placebo spray in treatment resistant depression (Clinical Trials Registration: NCT01998958). Fourteen of 67 patients (21%) in the ITT population were randomly selected from 3 clinical trial sites. The site-based MADRS interviews were recorded at the baseline and 2 h post-dose assessments on the first intranasal dosing day. Site-independent raters scored the recordings and were blinded to treatment and all reported TEAEs, including any transient dissociative/perceptual symptoms. None of the 7 placebo-assigned patients achieved a treatment response or remission at the 2-h post-dose assessment. Four of the 7 esketamine-assigned patients (57.1%) achieved a treatment response at 2-h post-dose, and 3 patients (42.9%) achieved remission. Three esketamine-treated patients experienced transient dissociative symptoms. The remote site-independent raters essentially replicated the site-based MADRS scores and yielded a 92.9% predictive value for matching treatment response and remission rates. This small pilot study affirms that blinded remote ratings (without the likelihood of functional unblinding) are comparable to site-based ratings of efficacy of esketamine nasal spray. The audio-digital recording method offers a reasonable strategy for other studies that may also be vulnerable to functional unblinding due to distinctive TEAEs.


Assuntos
Antidepressivos/farmacologia , Transtorno Depressivo Resistente a Tratamento/diagnóstico , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Ketamina/farmacologia , Avaliação de Processos e Resultados em Cuidados de Saúde , Adulto , Antidepressivos/administração & dosagem , Antidepressivos/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Ketamina/administração & dosagem , Ketamina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Sprays Nasais , Projetos Piloto , Efeito Placebo , Placebos , Valor Preditivo dos Testes , Escalas de Graduação Psiquiátrica/normas , Adulto Jovem
9.
Cereb Cortex ; 29(8): 3655-3665, 2019 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-30272146

RESUMO

22q11.2 Deletion Syndrome (22q11.2DS) is a genetic condition associated with a high prevalence of neuropsychiatric conditions that include autism spectrum disorder (ASD). While evidence suggests that clinical phenotypes represent distinct neurodevelopmental outcomes, it remains unknown whether this translates to the level of neurobiology. To fractionate the 22q11.2DS phenotype on the level of neuroanatomy, we examined differences in vertex-wise estimates of cortical volume, surface area, and cortical thickness between 1) individuals with 22q11.2DS (n = 62) and neurotypical controls (n = 57) and 2) 22q11.2DS individuals with ASD symptomatology (n = 30) and those without (n = 25). We firstly observed significant differences in surface anatomy between 22q11.2DS individuals and controls for all 3 neuroanatomical features, predominantly in parietotemporal regions, cingulate and dorsolateral prefrontal cortices. We also established that 22q11.2DS individuals with ASD symptomatology were neuroanatomically distinct from 22q11.2DS individuals without ASD symptoms, particularly in brain regions that have previously been linked to ASD (e.g., dorsolateral prefrontal cortices and the entorhinal cortex). Our findings indicate that different clinical 22q11.2DS phenotypes, including those with ASD symptomatology, may represent different neurobiological subgroups. The spatially distributed patterns of neuroanatomical differences associated with ASD symptomatology in 22q11.2DS may thus provide useful information for patient stratification and the prediction of clinical outcomes.


Assuntos
Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Síndrome de DiGeorge/diagnóstico por imagem , Adolescente , Adulto , Transtorno do Espectro Autista/etiologia , Transtorno do Espectro Autista/patologia , Transtorno do Espectro Autista/psicologia , Encéfalo/patologia , Estudos de Casos e Controles , Criança , Síndrome de DiGeorge/complicações , Síndrome de DiGeorge/patologia , Síndrome de DiGeorge/psicologia , Córtex Entorrinal/diagnóstico por imagem , Córtex Entorrinal/patologia , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/patologia , Humanos , Masculino , Tamanho do Órgão , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/patologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/patologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/patologia , Adulto Jovem
10.
Ir Med J ; 111(5): 749, 2018 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-30489044

RESUMO

Aims Annual seasonal influenza (flu) vaccination is recommended for all healthcare workers (HCW) in the Health Service Executive (HSE) in Ireland. This is to reduce the risk of HCW contracting the flu and onward transmission to their patients. HCW uptake remains less than ideal, despite extensive seasonal influenza campaigns and vaccination promotions. The aim of this study was to investigate the attitudes and uptake to flu vaccination among HCW, and to determine how much these influence their decision to be vaccinated. Methods A survey was sent to HCWs working in three healthcare facilities within HSE North-East following an outbreak of seasonal influenza in a local long-term care facility (LTCF), asking if HCW had been vaccinated for the 2016 to 2017 influenza season; the survey additionally included questions about attitudes and beliefs with respect to vaccination. Results Seventy HSE-employed HCWs in the North-East counties of Ireland responded to survey (93.3% responded to survey; 61.4% were based in long-term care facilties; 80.0% were female; and 35.7% were vaccinated for 2016 to 2017 influenza season). Most respondents reported that HCW flu vaccination was good example for patients (87.1%), while 92.9% acknowledged that it was important in healthcare facilities. The majority of HCW supported annual HCW flu vaccination (68.6%), with 52.9% of respondents reporting that they would be vaccinated for the 2017 to 2018 influenza season. However, only 35.7% agreed with mandatory HCW vaccination. Furthermore, 28.6% of respondents were concerned that flu vaccination was associated with side effects, and 22.9% were not aware that flu vaccination protected their patients. Previous flu vaccination was shown to be the only statistically significant predictor for HCW vaccination (p < 0.001). Discussion These results suggest there is need to address some attitudes and beliefs around HCW vaccination for seasonal influenza, in addition to removing some practical barriers to having vaccination, may help contribute to an improvement in vaccination uptake. It might be useful to focus on specific topics, to create a vaccine promotion culture, like adverse effects of vaccination, and collective benefits for patients in HSE to help improve HCW staff vaccination uptake.


Assuntos
Atitude do Pessoal de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Vacinas contra Influenza , Vacinação/estatística & dados numéricos , Feminino , Humanos , Masculino , Inquéritos e Questionários , Vacinação/psicologia
11.
Zoonoses Public Health ; 64(8): 655-661, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28432738

RESUMO

Lyme disease (LD) is a common tick-borne disease in New Hampshire (NH). While LD is a reportable condition and cases are counted for public health surveillance, many more people receive care for tick bites or diagnoses of LD than are reflected in surveillance data. NH's emergency department (ED) data system was queried for tick bite and LD-related encounters. Chief complaint text was queried for words related to LD or tick bites. International Classification of Diseases 9th Revision (ICD-9) codes were queried for the LD diagnosis code (088.81). Emergency department patient data were matched to reportable disease data to determine the proportion of ED patients reported to the health department as a suspected LD case. Data were analysed to calculate frequencies for key demographic and reporting characteristics. From 2010 to 2014, 13,615 tick bite or LD-related ED encounters were identified in NH, with most due to tick bites (76%). Of 3,256 patients with a LD-related ED encounter, 738 (23%) were reported to the health department as a suspected LD case. The geographic distribution of ED patients was similar to reported LD cases; however, the regions of the state that experienced higher rates of ED encounters were different than the regions that observed higher rates of reported LD cases. Seasonal distribution of ED encounters peaked earlier than reported LD cases with a second peak in the fall. While age and sex distribution was similar among ED patients and reported LD cases, the rates for children 5 years and younger and adults 65 years and older were greater for ED encounters. Patients frequently visit the ED to seek care for tick bites and suspected LD. Results of ED data analyses can be used to target education, in particular for ED providers and the public through timely distribution of evidence-based educational materials and training programmes.


Assuntos
Doença de Lyme/diagnóstico , Doença de Lyme/epidemiologia , Picadas de Carrapatos/epidemiologia , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , New Hampshire/epidemiologia , Estudos Retrospectivos , Adulto Jovem
12.
Transl Psychiatry ; 7(4): e1090, 2017 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-28398337

RESUMO

Autism spectrum conditions (ASC) are more prevalent in males than females. The biological basis of this difference remains unclear. It has been postulated that one of the primary causes of ASC is a partial disconnection of the frontal lobe from higher-order association areas during development (that is, a frontal 'disconnection syndrome'). Therefore, in the current study we investigated whether frontal connectivity differs between males and females with ASC. We recruited 98 adults with a confirmed high-functioning ASC diagnosis (61 males: aged 18-41 years; 37 females: aged 18-37 years) and 115 neurotypical controls (61 males: aged 18-45 years; 54 females: aged 18-52 years). Current ASC symptoms were evaluated using the Autism Diagnostic Observation Schedule (ADOS). Diffusion tensor imaging was performed and fractional anisotropy (FA) maps were created. Mean FA values were determined for five frontal fiber bundles and two non-frontal fiber tracts. Between-group differences in mean tract FA, as well as sex-by-diagnosis interactions were assessed. Additional analyses including ADOS scores informed us on the influence of current ASC symptom severity on frontal connectivity. We found that males with ASC had higher scores of current symptom severity than females, and had significantly lower mean FA values for all but one tract compared to controls. No differences were found between females with or without ASC. Significant sex-by-diagnosis effects were limited to the frontal tracts. Taking current ASC symptom severity scores into account did not alter the findings, although the observed power for these analyses varied. We suggest these findings of frontal connectivity abnormalities in males with ASC, but not in females with ASC, have the potential to inform us on some of the sex differences reported in the behavioral phenotype of ASC.


Assuntos
Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/patologia , Imagem de Tensor de Difusão , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/patologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/patologia , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Adulto Jovem
13.
Sci Rep ; 7: 42354, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28176862

RESUMO

Space radiation is a great danger to electronics and astronauts onboard space vessels. The spectral flux of space electrons, protons and ions for example in the radiation belts is inherently broadband, but this is a feature hard to mimic with conventional radiation sources. Using laser-plasma-accelerators, we reproduced relativistic, broadband radiation belt flux in the laboratory, and used this man-made space radiation to test the radiation hardness of space electronics. Such close mimicking of space radiation in the lab builds on the inherent ability of laser-plasma-accelerators to directly produce broadband Maxwellian-type particle flux, akin to conditions in space. In combination with the established sources, utilisation of the growing number of ever more potent laser-plasma-accelerator facilities worldwide as complementary space radiation sources can help alleviate the shortage of available beamtime and may allow for development of advanced test procedures, paving the way towards higher reliability of space missions.

14.
J Med Internet Res ; 18(6): e150, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-27363307

RESUMO

BACKGROUND: Despite numerous healthy eating campaigns, the prevalence of diets high in saturated fatty acids, sugar, and salt and low in fiber, fruit, and vegetables remains high. With more people than ever accessing the Internet, Web-based dietary assessment instruments have the potential to promote healthier dietary behaviors via personalized dietary advice. OBJECTIVE: The objectives of this study were to develop a dietary feedback system for the delivery of consistent personalized dietary advice in a multicenter study and to examine the impact of automating the advice system. METHODS: The development of the dietary feedback system included 4 components: (1) designing a system for categorizing nutritional intakes; (2) creating a method for prioritizing 3 nutrient-related goals for subsequent targeted dietary advice; (3) constructing decision tree algorithms linking data on nutritional intake to feedback messages; and (4) developing personal feedback reports. The system was used manually by researchers to provide personalized nutrition advice based on dietary assessment to 369 participants during the Food4Me randomized controlled trial, with an automated version developed on completion of the study. RESULTS: Saturated fatty acid, salt, and dietary fiber were most frequently selected as nutrient-related goals across the 7 centers. Average agreement between the manual and automated systems, in selecting 3 nutrient-related goals for personalized dietary advice across the centers, was highest for nutrient-related goals 1 and 2 and lower for goal 3, averaging at 92%, 87%, and 63%, respectively. Complete agreement between the 2 systems for feedback advice message selection averaged at 87% across the centers. CONCLUSIONS: The dietary feedback system was used to deliver personalized dietary advice within a multi-country study. Overall, there was good agreement between the manual and automated feedback systems, giving promise to the use of automated systems for personalizing dietary advice. TRIAL REGISTRATION: Clinicaltrials.gov NCT01530139; https://clinicaltrials.gov/ct2/show/NCT01530139 (Archived by WebCite at http://www.webcitation.org/6ht5Dgj8I).


Assuntos
Dieta , Retroalimentação , Internet , Avaliação Nutricional , Adulto , Algoritmos , Automação , Árvores de Decisões , Gorduras na Dieta , Fibras na Dieta , Feminino , Frutas , Educação em Saúde , Promoção da Saúde/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Cloreto de Sódio na Dieta , Inquéritos e Questionários , Verduras
15.
Cereb Cortex ; 26(7): 3297-309, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27130663

RESUMO

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition, which is accompanied by differences in gray matter neuroanatomy and white matter connectivity. However, it is unknown whether these differences are linked or reflect independent aetiologies. Using a multimodal neuroimaging approach, we therefore examined 51 male adults with ASD and 48 neurotypical controls to investigate the relationship between gray matter local gyrification (lGI) and white matter diffusivity in associated fiber tracts. First, ASD individuals had a significant increase in gyrification around the left pre- and post-central gyrus. Second, white matter fiber tracts originating and/or terminating in the cluster of increased lGI had a significant increase in axial diffusivity. This increase in diffusivity was predominantly observed in tracts in close proximity to the cortical sheet. Last, we demonstrate that the increase in lGI was significantly correlated with increased diffusivity of short tracts. This relationship was not significantly modulated by a main effect of group (i.e., ASD), which was more closely associated with gray matter gyrification than white matter diffusivity. Our findings suggest that differences in gray matter neuroanatomy and white matter connectivity are closely linked, and may reflect common rather than distinct aetiological pathways.


Assuntos
Transtorno do Espectro Autista/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adolescente , Adulto , Imagem de Tensor de Difusão , Humanos , Imageamento Tridimensional , Inteligência , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Tamanho do Órgão , Reconhecimento Automatizado de Padrão , Adulto Jovem
16.
Nature ; 530(7591): 477-80, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26911784

RESUMO

The variation in molar tooth size in humans and our closest relatives (hominins) has strongly influenced our view of human evolution. The reduction in overall size and disproportionate decrease in third molar size have been noted for over a century, and have been attributed to reduced selection for large dentitions owing to changes in diet or the acquisition of cooking. The systematic pattern of size variation along the tooth row has been described as a 'morphogenetic gradient' in mammal, and more specifically hominin, teeth since Butler and Dahlberg. However, the underlying controls of tooth size have not been well understood, with hypotheses ranging from morphogenetic fields to the clone theory. In this study we address the following question: are there rules that govern how hominin tooth size evolves? Here we propose that the inhibitory cascade, an activator-inhibitor mechanism that affects relative tooth size in mammals, produces the default pattern of tooth sizes for all lower primary postcanine teeth (deciduous premolars and permanent molars) in hominins. This configuration is also equivalent to a morphogenetic gradient, finally pointing to a mechanism that can generate this gradient. The pattern of tooth size remains constant with absolute size in australopiths (including Ardipithecus, Australopithecus and Paranthropus). However, in species of Homo, including modern humans, there is a tight link between tooth proportions and absolute size such that a single developmental parameter can explain both the relative and absolute sizes of primary postcanine teeth. On the basis of the relationship of inhibitory cascade patterning with size, we can use the size at one tooth position to predict the sizes of the remaining four primary postcanine teeth in the row for hominins. Our study provides a development-based expectation to examine the evolution of the unique proportions of human teeth.


Assuntos
Evolução Biológica , Hominidae/anatomia & histologia , Dente/anatomia & histologia , Animais , Feminino , Fósseis , Hominidae/classificação , Humanos , Masculino , Dente Molar/anatomia & histologia , Tamanho do Órgão , Filogenia , Especificidade da Espécie
17.
Food Chem Toxicol ; 83: 103-10, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26092325

RESUMO

Realistic estimates of chemical aggregate exposure are needed to ensure consumer safety. As exposure estimates are a critical part of the equation used to calculate acceptable "safe levels" and conduct quantitative risk assessments, methods are needed to produce realistic exposure estimations. To this end, a probabilistic aggregate exposure model was developed to estimate consumer exposure from several rinse off personal cleansing products containing the anti-dandruff preservative zinc pyrithione. The model incorporates large habits and practices surveys, containing data on frequency of use, amount applied, co-use along with market share, and combines these data at the level of the individual based on subject demographics to better estimate exposure. The daily-applied exposure (i.e., amount applied to the skin) was 3.79 mg/kg/day for the 95th percentile consumer. The estimated internal dose for the 95th percentile exposure ranged from 0.01-1.29 µg/kg/day after accounting for retention following rinsing and dermal penetration of ZnPt. This probabilistic aggregate exposure model can be used in the human safety assessment of ingredients in multiple rinse-off technologies (e.g., shampoo, bar soap, body wash, and liquid hand soap). In addition, this model may be used in other situations where refined exposure assessment is required to support a chemical risk assessment.


Assuntos
Qualidade de Produtos para o Consumidor , Cosméticos/química , Excipientes/toxicidade , Preparações para Cabelo/química , Modelos Biológicos , Compostos Organometálicos/toxicidade , Piridinas/toxicidade , Sabões/química , Administração Cutânea , Adulto , Animais , Cosméticos/efeitos adversos , Cosméticos/economia , Europa (Continente) , Excipientes/química , Asseio Animal , Preparações para Cabelo/efeitos adversos , Preparações para Cabelo/economia , Desinfecção das Mãos , Humanos , Internet , Compostos Organometálicos/química , Piridinas/química , Medição de Risco , Absorção Cutânea , Sabões/efeitos adversos , Sabões/economia , Solubilidade , Inquéritos e Questionários , Distribuição Tecidual , Toxicocinética , Estados Unidos
18.
Regul Toxicol Pharmacol ; 72(3): 673-82, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26071898

RESUMO

Ensuring the toxicological safety of fragrance ingredients used in personal care and cosmetic products is essential in product development and design, as well as in the regulatory compliance of the products. This requires an accurate estimation of consumer exposure which, in turn, requires an understanding of consumer habits and use of products. Where ingredients are used in multiple product types, it is important to take account of aggregate exposure in consumers using these products. This publication investigates the use of a newly developed probabilistic model, the Creme RIFM model, to estimate aggregate exposure to fragrance ingredients using the example of 2-phenylethanol (PEA). The output shown demonstrates the utility of the model in determining systemic and dermal exposure to fragrances from individual products, and aggregate exposure. The model provides valuable information not only for risk assessment, but also for risk management. It should be noted that data on the concentrations of PEA in products used in this article were obtained from limited sources and not the standard, industry wide surveys typically employed by the fragrance industry and are thus presented here to illustrate the output and utility of the newly developed model. They should not be considered an accurate representation of actual exposure to PEA.


Assuntos
Cosméticos , Exposição Ambiental/análise , Modelos Teóricos , Perfumes , Adulto , Qualidade de Produtos para o Consumidor , Europa (Continente) , Humanos , Álcool Feniletílico , Estados Unidos
19.
Regul Toxicol Pharmacol ; 72(3): 660-72, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26003515

RESUMO

Exposure of fragrance ingredients in cosmetics and personal care products to the population can be determined by way of a detailed and robust survey. The frequency and combinations of products used at specific times during the day will allow the estimation of aggregate exposure for an individual consumer, and to the sample population. In the present study, habits and practices of personal care and cosmetic products have been obtained from market research data for 36,446 subjects across European countries and the United States in order to determine the exposure to fragrance ingredients. Each subject logged their product uses, time of day and body application sites in an online diary for seven consecutive days. The survey data did not contain information on the amount of product used per occasion or body measurements, such as weight and skin surface area. Nevertheless, this was found from the literature where the likely amount of product used per occasion or body measurement could be probabilistically chosen from distributions of data based on subject demographics. The daily aggregate applied consumer product exposure was estimated based on each subject's frequency of product use, and Monte Carlo simulations of their likely product amount per use and body measurements. Statistical analyses of the habits and practices and consumer product exposure are presented, which show the robustness of the data and the ability to estimate aggregate consumer product exposure. Consequently, the data and modelling methods presented show potential as a means of performing ingredient safety assessments for personal care and cosmetics products.


Assuntos
Cosméticos , Exposição Ambiental , Modelos Teóricos , Perfumes , Adolescente , Adulto , Idoso , Qualidade de Produtos para o Consumidor , Bases de Dados Factuais , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
20.
Psychol Med ; 45(4): 795-805, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25111948

RESUMO

BACKGROUND: Increasing evidence suggests that autism is associated with abnormal white-matter (WM) anatomy and impaired brain 'connectivity'. While myelin plays a critical role in synchronized brain communication, its aetiological role in autistic symptoms has only been indirectly addressed by WM volumetric, relaxometry and diffusion tensor imaging studies. A potentially more specific measure of myelin content, termed myelin water fraction (MWF), could provide improved sensitivity to myelin alteration in autism. METHOD: We performed a cross-sectional imaging study that compared 14 individuals with autism and 14 age- and IQ-matched controls. T 1 relaxation times (T 1), T 2 relaxation times (T 2) and MWF values were compared between autistic subjects, diagnosed using the Autism Diagnostic Interview - Revised (ADI-R), with current symptoms assessed using the Autism Diagnostic Observation Schedule (ADOS) and typical healthy controls. Correlations between T 1, T 2 and MWF values with clinical measures [ADI-R, ADOS, and the Autism Quotient (AQ)] were also assessed. RESULTS: Individuals with autism showed widespread WM T 1 and MWF differences compared to typical controls. Within autistic individuals, worse current social interaction skill as measured by the ADOS was related to reduced MWF although not T 1. No significant differences or correlations with symptoms were observed with respect to T 2. CONCLUSIONS: Autistic individuals have significantly lower global MWF and higher T 1, suggesting widespread alteration in tissue microstructure and biochemistry. Areas of difference, including thalamic projections, cerebellum and cingulum, have previously been implicated in the disorder; however, this is the first study to specifically indicate myelin alteration in these regions.


Assuntos
Transtorno Autístico/patologia , Imageamento por Ressonância Magnética/métodos , Bainha de Mielina/patologia , Substância Branca/patologia , Adulto , Humanos , Masculino , Bainha de Mielina/química , Substância Branca/química , Adulto Jovem
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