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1.
Int J Oral Maxillofac Surg ; 51(8): 1027-1033, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35065850

RESUMO

A retrospective clinicopathological analysis was performed to compare 35 proliferative verrucous leukoplakia (PVL), 40 leukoplakia without dysplasia (LK), 48 oral lichen planus (OLP)/oral lichenoid lesions (OLL), and 11 verrucous carcinoma (VC) (N = 134). The PVL group comprised 24 female and 11 male patients (mean age 66.5 years), with two to six sites involved (mean 3.1 sites) and multiple biopsies over time (mean 7.1/case). All PVL cases developed malignancy: 77.1% squamous cell and 40% verrucous carcinoma; 68.6% had multiple sites of malignancy. None showed local or distant metastatic spread. Five-year disease-specific survival was 88.6%. In LK and OLP/OLL, malignant transformation was significantly lower than in PVL (2.5% and 2.1%, respectively). Invasive squamous cell carcinoma was not reported in any conventional VC. Immunohistochemical histomorphometric analysis for p53, COX-2, and podoplanin showed no significant differences between the groups. PVL may overlap with LK, OLP/OLL, and VC, but has a persistent aggressive behaviour and high malignant transformation rate. The overlapping features may delay recognition as PVL. The results emphasize the need for a detailed clinicopathological definition of PVL, and long-term close monitoring to ensure progression to PVL and malignancy are recognized in time. The management of this persistent aggressive condition is challenging.


Assuntos
Carcinoma de Células Escamosas , Carcinoma Verrucoso , Neoplasias Bucais , Idoso , Carcinoma de Células Escamosas/patologia , Carcinoma Verrucoso/patologia , Transformação Celular Neoplásica/patologia , Feminino , Humanos , Leucoplasia Oral , Masculino , Neoplasias Bucais/patologia , Estudos Retrospectivos
2.
Neurochirurgie ; 68(2): 223-227, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33845114

RESUMO

BACKGROUND: Intraoperative control of optic nerve function conservation during neurosurgical operations currently relies mainly on visual evoked potential monitoring. Unfortunately, this detects peril only when the visual pathways are already compromised, sometimes irreversibly. In contrast, electrophysiological stimulation mapping of the nerves can be a fully preventive measure. However, direct sensory nerve mapping requires the patient to be awake during surgery, which is unfeasible for surgeries targeting the optic nerve area. Another possible approach to sensory nerve mapping involves unconditioned electrophysiological responses evoked by sensory nerve stimulation. The key point for this approach is the possibility of obtaining such responses for a particular sensory nerve under surgical anesthesia. CASE REPORT: A 52-year-old woman presented with meningioma in the area of right optic nerve and chiasm. She underwent microsurgical removal of the tumor through the transciliary supraorbital approach. During surgery, electrodes at the inferior margin of the right orbit repeatedly recorded electrophysiological reactions following contacts and displacements of the right optic nerve by the surgical instruments. CONCLUSIONS: The observed reactions suggest that either the unconditioned blink reflex or antidromic electroretinographic response to optic nerve irritation was conserved under total intravenous anesthesia. This observation might be of value for development of intraoperative optic nerve mapping. This in turn could increase patient safety by identifying the exact optic nerve location before any negative impact on it.


Assuntos
Neoplasias Meníngeas , Meningioma , Potenciais Evocados Visuais , Feminino , Humanos , Meningioma/cirurgia , Pessoa de Meia-Idade , Nervo Óptico/cirurgia , Vias Visuais
4.
Ultrasound Obstet Gynecol ; 58(3): 450-456, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34198360

RESUMO

OBJECTIVES: To determine the immunogenicity and reactogenicity of the Pfizer/BioNTech BNT162b2 mRNA coronavirus disease 2019 (COVID-19) vaccine among pregnant women compared with non-pregnant women, and to evaluate obstetric outcome following vaccination. METHODS: This was an observational case-control study of pregnant women who were vaccinated with a two-dose regimen of the BNT162b2 vaccine during gestation between January and February 2021 (study group) and age-matched non-pregnant women who received the vaccine during the same time period (control group). Participants received a digital questionnaire 1-4 weeks after the second dose and were asked to provide information regarding demographics, medication, medical history, history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, timing of COVID-19 vaccine doses and side effects after each vaccine dose. A second digital questionnaire, regarding current pregnancy and delivery outcomes, was sent to patients in the study group after the calculated due date. All recruited women were offered a serology blood test for SARS-CoV-2 immunoglobulin G (IgG) following the second vaccination dose and SARS-CoV-2 IgG levels were compared between the two groups. RESULTS: Of 539 pregnant women who were recruited after completion of the two-dose regimen of the vaccine, 390 returned the digital questionnaire and were included in the study group and compared to 260 age-matched non-pregnant vaccinated women. The rates of rash, fever and severe fatigue following vaccination among pregnant women were comparable to those in non-pregnant women. Myalgia, arthralgia and headache were significantly less common among pregnant women after each dose, local pain or swelling and axillary lymphadenopathy were significantly less common among pregnant women after the first and second doses, respectively, while paresthesia was significantly more common among the pregnant population after the second dose. Among pregnant women, there were no significant differences in the rates of side effects according to whether the vaccine was administered during the first, second or third trimester of pregnancy, except for local pain/swelling, which was significantly less common after the first dose when administered during the third trimester, and uterine contractions, which were significantly more common after the second dose when administered during the third trimester. The rates of obstetric complications, including uterine contractions (1.3% after the first dose and 6.4% after the second dose), vaginal bleeding (0.3% after the first dose and 1.5% after the second dose) and prelabor rupture of membranes (0% after the first dose and 0.8% after the second dose), were very low following vaccination. All serum samples in both groups were positive for SARS-CoV-2 IgG. However, pregnant women had significantly lower serum SARS-CoV-2 IgG levels compared to non-pregnant women (signal-to-cut-off ratio, 27.03 vs 34.35, respectively; P < 0.001). Among the 57 pregnant women who delivered during the study period and who completed the second questionnaire, median gestational age at delivery was 39.5 (interquartile range, 38.7-40.0) weeks, with no cases of preterm birth < 37 weeks, no cases of fetal or neonatal death and two (3.5%) cases of admission to the neonatal intensive care unit for respiratory support. CONCLUSIONS: The adverse-effect profile and short-term obstetric and neonatal outcomes among pregnant women who were vaccinated with the BNT162b2 vaccine at any stage of pregnancy do not indicate any safety concerns. The vaccine is effective in generating a humoral immune response in pregnant women, although SARS-CoV-2 IgG levels were lower than those observed in non-pregnant vaccinated women. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Vacinas contra COVID-19 , COVID-19/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Adulto , Vacina BNT162 , COVID-19/imunologia , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/imunologia , Estudos de Casos e Controles , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Resultado da Gravidez
5.
J Intern Med ; 288(6): 699-710, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32633011

RESUMO

INTRODUCTION: The gut microbiome may contribute to the development of obesity. So far, the extent of microbiome variation in people with obesity has not been determined in large cohorts and for a wide range of body mass index (BMI). Here, we aimed to investigate whether the faecal microbial metagenome can explain the variance in several clinical phenotypes associated with morbid obesity. METHODS: Caucasian subjects were recruited at our hospital. Blood pressure and anthropometric measurements were taken. Dietary intake was determined using questionnaires. Shotgun metagenomic sequencing was performed on faecal samples from 177 subjects. RESULTS: Subjects without obesity (n = 82, BMI 24.7 ± 2.9 kg m-2 ) and subjects with obesity (n = 95, BMI 38.6 ± 5.1 kg m-2 ) could be clearly distinguished based on microbial composition and microbial metabolic pathways. A total number of 52 bacterial species differed significantly in people with and without obesity. Independent of dietary intake, we found that microbial pathways involved in biosynthesis of amino acids were enriched in subjects with obesity, whereas pathways involved in the degradation of amino acids were depleted. Machine learning models showed that more than half of the variance in body fat composition followed by BMI could be explained by the gut microbiome, composition and microbial metabolic pathways, compared with 6% of variation explained in triglycerides and 9% in HDL. CONCLUSION: Based on the faecal microbiota composition, we were able to separate subjects with and without obesity. In addition, we found strong associations between gut microbial amino acid metabolism and specific microbial species in relation to clinical features of obesity.


Assuntos
Microbioma Gastrointestinal , Obesidade Mórbida/microbiologia , Magreza/microbiologia , Adulto , Aminoácidos/metabolismo , Índice de Massa Corporal , Fezes/microbiologia , Humanos , Aprendizado de Máquina , Redes e Vias Metabólicas , Metagenômica , Pessoa de Meia-Idade , Obesidade Mórbida/metabolismo , Magreza/metabolismo
6.
Nat Med ; 26(8): 1235-1239, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32719484

RESUMO

Three inherited autosomal dominant conditions-BRCA-related hereditary breast and ovarian cancer (HBOC), Lynch syndrome (LS) and familial hypercholesterolemia (FH)-have been termed the Centers for Disease Control and Prevention Tier 1 (CDCT1) genetic conditions, for which early identification and intervention have a meaningful potential for clinical actionability and a positive impact on public health1. In typical medical practice, genetic testing for these conditions is based on personal or family history, ethnic background or other demographic characteristics2. In this study of a cohort of 26,906 participants in the Healthy Nevada Project (HNP), we first evaluated whether population screening could efficiently identify carriers of these genetic conditions and, second, we evaluated the impact of genetic risk on health outcomes for these participants. We found a 1.33% combined carrier rate for pathogenic and likely pathogenic (P/LP) genetic variants for HBOC, LS and FH. Of these carriers, 21.9% of participants had clinically relevant disease, among whom 70% had been diagnosed with relevant disease before age 65. Moreover, 90% of the risk carriers had not been previously identified, and less than 19.8% of these had documentation in their medical records of inherited genetic disease risk, including family history. In a direct follow-up survey with all carriers, only 25.2% of individuals reported a family history of relevant disease. Our experience with the HNP suggests that genetic screening in patients could identify at-risk carriers, who would not be otherwise identified in routine care.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Testes Genéticos , Genética Populacional , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Hiperlipoproteinemia Tipo II/genética , Adolescente , Adulto , Idoso , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Feminino , Triagem de Portadores Genéticos/métodos , Síndrome Hereditária de Câncer de Mama e Ovário/diagnóstico , Síndrome Hereditária de Câncer de Mama e Ovário/patologia , Heterozigoto , Humanos , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/patologia , Pessoa de Meia-Idade
7.
Forensic Sci Int Synerg ; 1: 243-252, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32411977

RESUMO

This study presents analysis of forensic science research funded by UK Research and Innovation (UKRI) research councils (2009-2018), representing 150 projects with a cumulative value of £56.1 m (0.01% of the total UKRI budget over this time period). The findings indicate that dedicated forensic science funding represents only 46.0% of the projects included in the dataset. Research focussed on developing technological outputs represented 69.5% of the total funding (£37.2 m) in comparison to foundational research which represented 19.2% (£10.7 m). Traditional forensic science evidence types such as fingerprints and DNA received 1.3% and 5.1% of the total funding respectively, in comparison to digital and cyber projects which received 25.7%. These data offer insight into the scale of the funding crisis in forensic science in the UK, and the need to increase the resources available, to develop ways of articulating value and to ensure that both technological and foundational research are enabled.

8.
J Endocrinol ; 239(3): 303-312, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30400010

RESUMO

The importance of estrogen receptor α (ERα) for the regulation of bone mass in males is well established. ERα mediates estrogenic effects both via nuclear and membrane-initiated ERα (mERα) signaling. The role of mERα signaling for the effects of estrogen on bone in male mice is unknown. To investigate the role of mERα signaling, we have used mice (Nuclear-Only-ER; NOER) with a point mutation (C451A), which results in inhibited trafficking of ERα to the plasma membrane. Gonadal-intact male NOER mice had a significantly decreased total body areal bone mineral density (aBMD) compared to WT littermates at 3, 6 and 9 months of age as measured by dual-energy X-ray absorptiometry (DEXA). High-resolution microcomputed tomography (µCT) analysis of tibia in 3-month-old males demonstrated a decrease in cortical and trabecular thickness in NOER mice compared to WT littermates. As expected, estradiol (E2) treatment of orchidectomized (ORX) WT mice increased total body aBMD, trabecular BV/TV and cortical thickness in tibia compared to placebo treatment. E2 treatment increased these skeletal parameters also in ORX NOER mice. However, the estrogenic responses were significantly decreased in ORX NOER mice compared with ORX WT mice. In conclusion, mERα is essential for normal estrogen signaling in both trabecular and cortical bone in male mice. Increased knowledge of estrogen signaling mechanisms in the regulation of the male skeleton may aid in the development of new treatment options for male osteoporosis.


Assuntos
Osso e Ossos/metabolismo , Receptor alfa de Estrogênio/metabolismo , Estrogênios/metabolismo , Animais , Densidade Óssea , Remodelação Óssea , Masculino , Camundongos
9.
Science ; 362(6416): 794-799, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30262635

RESUMO

Here we explore factors potentially linked to the enhanced major hurricane activity in the Atlantic Ocean during 2017. Using a suite of high-resolution model experiments, we show that the increase in 2017 major hurricanes was not primarily caused by La Niña conditions in the Pacific Ocean but rather triggered mainly by pronounced warm sea surface conditions in the tropical North Atlantic. Further, we superimpose a similar pattern of North Atlantic surface warming on data for long-term increasing sea surface temperature (a product of increases in greenhouse gas concentrations and decreases in aerosols) to show that this warming trend will likely lead to even higher numbers of major hurricanes in the future. The key factor controlling Atlantic major hurricane activity appears to be the degree to which the tropical Atlantic warms relative to the rest of the global ocean.

10.
Clin Transl Gastroenterol ; 9(5): 155, 2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29799027

RESUMO

BACKGROUND: Gut microbiota-derived short-chain fatty acids (SCFAs) have been associated with beneficial metabolic effects. However, the direct effect of oral butyrate on metabolic parameters in humans has never been studied. In this first in men pilot study, we thus treated both lean and metabolic syndrome male subjects with oral sodium butyrate and investigated the effect on metabolism. METHODS: Healthy lean males (n = 9) and metabolic syndrome males (n = 10) were treated with oral 4 g of sodium butyrate daily for 4 weeks. Before and after treatment, insulin sensitivity was determined by a two-step hyperinsulinemic euglycemic clamp using [6,6-2H2]-glucose. Brown adipose tissue (BAT) uptake of glucose was visualized using 18F-FDG PET-CT. Fecal SCFA and bile acid concentrations as well as microbiota composition were determined before and after treatment. RESULTS: Oral butyrate had no effect on plasma and fecal butyrate levels after treatment, but did alter other SCFAs in both plasma and feces. Moreover, only in healthy lean subjects a significant improvement was observed in both peripheral (median Rd: from 71 to 82 µmol/kg min, p < 0.05) and hepatic insulin sensitivity (EGP suppression from 75 to 82% p < 0.05). Although BAT activity was significantly higher at baseline in lean (SUVmax: 12.4 ± 1.8) compared with metabolic syndrome subjects (SUVmax: 0.3 ± 0.8, p < 0.01), no significant effect following butyrate treatment on BAT was observed in either group (SUVmax lean to 13.3 ± 2.4 versus metabolic syndrome subjects to 1.2 ± 4.1). CONCLUSIONS: Oral butyrate treatment beneficially affects glucose metabolism in lean but not metabolic syndrome subjects, presumably due to an altered SCFA handling in insulin-resistant subjects. Although preliminary, these first in men findings argue against oral butyrate supplementation as treatment for glucose regulation in human subjects with type 2 diabetes mellitus.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Butiratos/administração & dosagem , Glucose/metabolismo , Resistência à Insulina/fisiologia , Síndrome Metabólica/metabolismo , Magreza/metabolismo , Administração Oral , Adulto , Ácidos e Sais Biliares/metabolismo , Metabolismo Energético , Ácidos Graxos Voláteis/sangue , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Fluordesoxiglucose F18 , Microbioma Gastrointestinal , Humanos , Fígado/metabolismo , Masculino , Síndrome Metabólica/tratamento farmacológico , Projetos Piloto , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Adulto Jovem
11.
Neurogastroenterol Motil ; 30(6): e13299, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29383802

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is a common gastrointestinal disorder associated with altered gastrointestinal microflora and increased nociception to colonic distension. This visceral hypersensitivity can be reversed in our rat maternal separation model by fungicides. Menthacarin® is a proprietary combination of essential oils from Mentha x piperita L. and Carum carvi. Because these oils exhibit antifungal and antibacterial properties, we investigated whether Menthacarin® can reverse existing visceral hypersensitivity in maternally separated rats. METHODS: In non-handled and maternally separated rats, we used the visceromotor responses to colorectal distension as measure for visceral sensitivity. We evaluated this response before and 24 hours after water-avoidance stress and after 7 days treatment with Menthacarin® or control. The pre- and post-treatment mycobiome and microbiome were characterized by sequencing of fungal internal transcribed spacer 1 (ITS-1) and bacterial 16s rDNA regions. In vitro antifungal and antimicrobial properties of Menthacarin® were studied with radial diffusion assay. KEY RESULTS: Menthacarin® inhibited in vitro growth of yeast and bacteria. Water-avoidance caused visceral hypersensitivity in maternally separated rats, and this was reversed by treatment. Multivariate analyses of ITS-1 and 16S high throughput data showed that maternal separation, induced changes in the myco- and microbiome. Menthacarin® treatment of non-handled and maternally separated rats shifted the mycobiomes to more similar compositions. CONCLUSIONS & INFERENCES: The development of visceral hypersensitivity in maternally separated rats and the Menthacarin® -mediated reversal of hypersensitivity is associated with changes in the mycobiome. Therefore, Menthacarin® may be a safe and effective treatment option that should be tested for IBS.


Assuntos
Hiperalgesia/tratamento farmacológico , Micobioma/efeitos dos fármacos , Óleos Voláteis/administração & dosagem , Óleos de Plantas/administração & dosagem , Dor Visceral/tratamento farmacológico , Animais , Animais Recém-Nascidos , Antibacterianos/administração & dosagem , Antibacterianos/isolamento & purificação , Antifúngicos/administração & dosagem , Antifúngicos/isolamento & purificação , Combinação de Medicamentos , Hiperalgesia/microbiologia , Hiperalgesia/psicologia , Masculino , Privação Materna , Mentha piperita , Micobioma/fisiologia , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/isolamento & purificação , Ratos , Ratos Long-Evans , Dor Visceral/microbiologia , Dor Visceral/psicologia
12.
Sci Justice ; 57(5): 349-360, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28889864

RESUMO

In recent years there has been growing interest in environmental forms of trace evidence, and ecological trace evidence collected from footwear has proved valuable within casework. Simultaneously, there has been growing awareness of the need for empirical experimentation to underpin forensic inferences. Diatoms are unicellular algae, and each cell (or 'frustule') consists of two valves which are made of silica, a robust material that favours their preservation both in sediments and within forensic scenarios. A series of experiments were carried out to investigate the transfer and persistence of diatoms upon common footwear materials, a recipient surface that has historically been overlooked by studies of persistence. The effectiveness of two novel extraction techniques (jet rinsing, and heating and agitation with distilled water) was compared to the established extraction technique of hydrogen peroxide digestion, for a suite of five common footwear materials: canvas, leather, and 'suede' (representing upper materials), and rubber and polyurethane (representing sole materials). It was observed that the novel extraction technique of heating and agitation with distilled water did not extract fewer diatom valves, or cause increased fragmentation of valves, when compared to peroxide digestion, suggesting that the method may be viable where potentially hazardous chemical reactions may be encountered with the peroxide digestion method. Valves could be extracted from all five footwear materials after 3min of immersion, and more valves were extracted from the rougher, woven upper materials than the smoother sole materials. Canvas yielded the most valves (a mean of 2511/cm2) and polyurethane the fewest (a mean of 15/cm2). The persistence of diatoms on the three upper materials was addressed with a preliminary pilot investigation, with ten intervals sampled between 0 and 168h. Valves were seen to persist in detectable quantities after 168h on all three upper materials. However, some samples produced slides with no valves, and the earliest time after which no diatom valves were found was 4h after the transfer. Analysis of the particle size distributions over time, by image analysis, suggests that the retention of diatoms may be size-selective; after 168h, no particles larger than 200µm2 could be found on the samples of canvas, and >95% of the particles on the samples of suede were less than or equal to 200µm2. A pilot investigation into the effects of immersion interval was carried out upon samples of canvas. Greater numbers of valves were extracted from the samples with longer immersion intervals, but even after 30s, >500 valves could be recovered per cm2, suggesting that footwear may be sampled for diatoms even if the contact with a water body may have been brief. These findings indicate that, if the variability within and between experimental runs can be addressed, there is significant potential for diatoms to be incorporated into the trace analysis of footwear and assist forensic reconstructions.


Assuntos
Diatomáceas , Água Doce , Sapatos , Manejo de Espécimes/métodos , Diatomáceas/isolamento & purificação , Ciências Forenses , Humanos , Imersão
13.
Artigo em Russo | MEDLINE | ID: mdl-28805756

RESUMO

AIM: To evaluate the efficacy of neuromonitoring methods in prevention of postoperative neurological complications and estimation of predictive power of intraoperative changes in monitored characteristics. MATERIAL AND METHODS: Retrospective study examined 240 patients, operated in the years 2014-2015 using intraoperative neurophysiological monitoring. One hundred and seventy-three patients suffered from hemispheric lesions and 67 had lesions located in or near the brainstem. Somatosensory evoked potentials (SSEP) were monitored in 152 cases, visual in 32, brainstem acoustic in 22, transcranial motor in 36; stimulation mapping of motor cortex was performed in 69 surgeries, and cranial nerves identification in 27. EEG was recorded in 7 patients, and 3 of them were woke up during the surgery for speech mapping. RESULTS: The sensitivity of the SSEP in motor dysfunction detection was low (33%), while the specificity was relatively high (82%). These characteristics for visual and motor evoked potentials were close to 100% provided that the parameters of anesthesia met the corresponding requirements. The most effective methods in respect of prevention of postoperative dysfunctions were the stimulation mapping of functionally significant areas (motor and speech) and motor pathways mapping. CONCLUSION: Intraoperative neuromonitoring reduces a number of neurological complications after neurosurgical operations. The SSEP method is not sensitive enough in surgeries that could affect motor centers and/or pathways, and multimodal monitoring combining SSEP and motor responses recording during transcranial and/or direct electrical brain stimulation. Successful monitoring requires highly coordinated actions between neurophysiologists, neurosurgeons and anesthesiologists.


Assuntos
Neoplasias Encefálicas/cirurgia , Monitorização Neurofisiológica Intraoperatória , Procedimentos Neurocirúrgicos , Potencial Evocado Motor , Potenciais Somatossensoriais Evocados , Feminino , Humanos , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade
14.
Science ; 355(6326): 733-735, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28209896

RESUMO

Nectar-feeding animals have among the highest recorded metabolic rates. High aerobic performance is linked to oxidative damage in muscles. Antioxidants in nectar are scarce to nonexistent. We propose that nectarivores use nectar sugar to mitigate the oxidative damage caused by the muscular demands of flight. We found that sugar-fed moths had lower oxidative damage to their flight muscle membranes than unfed moths. Using respirometry coupled with δ13C analyses, we showed that moths generate antioxidant potential by shunting nectar glucose to the pentose phosphate pathway (PPP), resulting in a reduction in oxidative damage to the flight muscles. We suggest that nectar feeding, the use of PPP, and intense exercise are causally linked and have allowed the evolution of powerful fliers that feed on nectar.


Assuntos
Sacarose na Dieta/metabolismo , Comportamento Alimentar , Voo Animal , Mariposas/fisiologia , Estresse Oxidativo , Néctar de Plantas/metabolismo , Aerobiose , Animais , Glucose/metabolismo , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Mariposas/metabolismo , Músculos/metabolismo , Via de Pentose Fosfato
15.
Solid State Nucl Magn Reson ; 78: 40-44, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27455192

RESUMO

(125)Te NMR spectra and spin-lattice relaxation times, T1, have been measured for several GeTe-based materials with Te excess. The spectra show inhomogeneous broadening by several thousand ppm and a systematic variation in T1 relaxation time with resonance frequency. The quadratic dependence of the spin-lattice relaxation rate, 1/T1, on the Knight shift in the Korringa relation is found to be valid over a wide range of Knight shifts. This result confirms that T1 relaxation in GeTe-based materials is mostly dominated by hyperfine interaction between nuclei and free charge carriers. In GeTe with 2.5% excess of Te, about 15% of the material exhibits a Knight shift of ≥4500ppm and a T1 of only 0.3ms, indicating a high hole concentration that could correspond to close to 50% vacancies on the Ge sublattice in this component. Our findings provide a basis for determining the charge carrier concentration and its distribution in complex thermoelectric and phase-change tellurides, which should lead to a better understanding of electronic and thermal transport properties as well as chemical bonding in these materials.

16.
Sci Rep ; 6: 29473, 2016 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-27388455

RESUMO

Estrogen receptor α (ERα) signaling leads to cellular responses in several tissues and in addition to nuclear ERα-mediated effects, membrane ERα (mERα) signaling may be of importance. To elucidate the significance, in vivo, of mERα signaling in multiple estrogen-responsive tissues, we have used female mice lacking the ability to localize ERα to the membrane due to a point mutation in the palmitoylation site (C451A), so called Nuclear-Only-ER (NOER) mice. Interestingly, the role of mERα signaling for the estrogen response was highly tissue-dependent, with trabecular bone in the axial skeleton being strongly dependent (>80% reduction in estrogen response in NOER mice), cortical and trabecular bone in long bones, as well as uterus and thymus being partly dependent (40-70% reduction in estrogen response in NOER mice) and effects on liver weight and total body fat mass being essentially independent of mERα (<35% reduction in estrogen response in NOER mice). In conclusion, mERα signaling is important for the estrogenic response in female mice in a tissue-dependent manner. Increased knowledge regarding membrane initiated ERα actions may provide means to develop new selective estrogen receptor modulators with improved profiles.


Assuntos
Membrana Celular/metabolismo , Estradiol/farmacologia , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Úmero/metabolismo , Tecido Adiposo/efeitos dos fármacos , Animais , Membrana Celular/genética , Retroalimentação Fisiológica , Feminino , Lipoilação , Fígado/metabolismo , Camundongos , Mutação , Tamanho do Órgão/efeitos dos fármacos , Especificidade de Órgãos , Ovariectomia , Transdução de Sinais , Timo/metabolismo , Útero/metabolismo
17.
Neurotoxicol Teratol ; 53: 55-63, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26548404

RESUMO

Acute exposures to some individual polycyclic aromatic hydrocarbons (PAHs) and complex PAH mixtures are known to cause cardiac malformations and edema in the developing fish embryo. However, the heart is not the only organ impacted by developmental PAH exposure. The developing brain is also affected, resulting in lasting behavioral dysfunction. While acute exposures to some PAHs are teratogenically lethal in fish, little is known about the later life consequences of early life, lower dose subteratogenic PAH exposures. We sought to determine and characterize the long-term behavioral consequences of subteratogenic developmental PAH mixture exposure in both naive killifish and PAH-adapted killifish using sediment pore water derived from the Atlantic Wood Industries Superfund Site. Killifish offspring were embryonically treated with two low-level PAH mixture dilutions of Elizabeth River sediment extract (ERSE) (TPAH 5.04 µg/L and 50.4 µg/L) at 24h post fertilization. Following exposure, killifish were raised to larval, juvenile, and adult life stages and subjected to a series of behavioral tests including: a locomotor activity test (4 days post-hatch), a sensorimotor response tap/habituation test (3 months post hatch), and a novel tank diving and exploration test (3months post hatch). Killifish were also monitored for survival at 1, 2, and 5 months over 5-month rearing period. Developmental PAH exposure caused short-term as well as persistent behavioral impairments in naive killifish. In contrast, the PAH-adapted killifish did not show behavioral alterations following PAH exposure. PAH mixture exposure caused increased mortality in reference killifish over time; yet, the PAH-adapted killifish, while demonstrating long-term rearing mortality, had no significant changes in mortality associated with ERSE exposure. This study demonstrated that early embryonic exposure to PAH-contaminated sediment pore water caused long-term locomotor and behavioral alterations in killifish, and that locomotor alterations could be observed in early larval stages. Additionally, our study highlights the resistance to behavioral alterations caused by low-level PAH mixture exposure in the adapted killifish population. Furthermore, this is the first longitudinal behavioral study to use killifish, an environmentally important estuarine teleost fish, and this testing framework can be used for future contaminant assessment.


Assuntos
Adaptação Biológica/efeitos dos fármacos , Embrião não Mamífero/anormalidades , Desenvolvimento Embrionário/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Embrião não Mamífero/efeitos dos fármacos , Meio Ambiente , Comportamento Exploratório/efeitos dos fármacos , Fundulidae , Cardiopatias Congênitas/induzido quimicamente , Larva/efeitos dos fármacos , Reflexo de Sobressalto/efeitos dos fármacos , Estatísticas não Paramétricas , Fatores de Tempo
18.
Vox Sang ; 110(3): 227-35, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26646434

RESUMO

BACKGROUND AND OBJECTIVES: Di-2-ethylhexyl phthalate (DEHP) is a blood bag plasticizer. It is also a toxin, raising concerns for vulnerable populations, for example, neonates and infants. Here, the in vitro quality of red cell concentrates (RCC) stored in paediatric bags formulated with alternative plasticizers to DEHP was compared. MATERIALS AND METHODS: RCC were pooled and split into polyvinylchloride (PVC)/DEHP, PVC/1,2-cyclohexanedicarboxylic acid diisononyl ester (DINCH) or PVC/butyryl trihexyl citrate (BTHC) bags. Quality was assessed on storage days 5, 21, 35 and 43. RESULTS: Metabolism differed among the bags: pCO2 levels were lowest and pO2 were highest in BTHC bags. Glucose consumption and lactate production suggested higher metabolic rates in BTHC bags. ATP levels were best maintained in DINCH bags (day 43 mean level: 2·86 ± 0·29 µmol/g Hb). RCC in BTHC bags had the greatest potassium release (54·6 ± 3·0 mm on day 43). From day 21, haemolysis was higher in BTHC bags (P < 0·01) and by day 43 had exceeded 0·8% (0·85 ± 0·10%). RCC in BTHC bags showed more microparticle formation than RCC in DEHP or DINCH bags. CONCLUSION: The results suggest that the BTHC formulation used was detrimental to RBC quality. DINCH bags could be a viable alternative to DEHP: they outperformed DEHP bags energetically, with better maintenance of ATP levels.


Assuntos
Preservação de Sangue/métodos , Dietilexilftalato/química , Eritrócitos/metabolismo , Plastificantes/química , Cloreto de Polivinila/química , Trifosfato de Adenosina/análise , Contagem de Células Sanguíneas , Gasometria , Preservação de Sangue/instrumentação , Dietilexilftalato/farmacologia , Eritrócitos/efeitos dos fármacos , Glucose/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Lactente , Recém-Nascido , Ácido Láctico/metabolismo , Plastificantes/farmacologia , Cloreto de Polivinila/farmacologia , Potássio/análise , Potássio/metabolismo , Temperatura , Fatores de Tempo
19.
Neurotoxicol Teratol ; 52(Pt B): 220-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26344674

RESUMO

BACKGROUND: Organophosphate flame retardants (OPFRs) have grown in usage since concerns about the health effects of the previously used polybrominated flame retardants led to their being phased out. The potential for OPFRs to cause adverse health effects of their own is still unexamined. Because of their structural similarities to organophosphate pesticides, which have themselves been heavily researched and shown to be neurobehavioral teratogens, we investigated the possibility that developmental exposure to two OPFRs, triphenyl phosphate (TPHP), and tris(1,3-dichloroisopropyl)phosphate (TDCIPP) might lead to behavioral impairment across the lifespan, as has been observed with the organophosphate pesticide chlorpyrifos. METHODS: Zebrafish were exposed to 0.03 or 0.3 µM of TPHP, TDCIPP, or chlorpyrifos from 0 to 5 days post fertilization. Vehicle control consisted of 0.03% solution of DMSO. At 6 days post fertilization, larvae were tested on a locomotor assay. Separate cohorts of 6 day old larvae that were not tested on the larval assay were allowed to grow to adulthood. At 12 weeks post fertilization, these adult zebrafish were tested on a battery of behavioral assays that included tests of novel environment exploration, startle habituation, social affiliation, and predator escape. RESULTS: Developmental exposure altered zebrafish behavior across the lifespan. Larval zebrafish exposed to the 0.03 µM doses of chlorpyrifos or TDCIPP exhibited significant (p<0.05) hyperactivity in the locomotor assay. Organophosphate exposure significantly (p<0.05) altered the time course of adult zebrafish behavior in the novel environment, startle habituation, and social affiliation assays. Predator escape behavior was significantly (p<0.05) reduced in fish exposed to the 0.3 µM dose of TDCIPP. Exposure also caused hyperactivity in adult fish, with fish exposed to the 0.3 µM dose of TDCIPP exhibiting significantly (p<0.05) elevated locomotor behavior in the novel environment assay. DISCUSSION: Early developmental exposure to OPFRs produced behavioral impairment that persisted into adulthood. These findings support broader research investigating the role of organophosphate compounds, including the OPFRs used here, in developmental neurotoxicity.


Assuntos
Comportamento Animal/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Retardadores de Chama/toxicidade , Atividade Motora/efeitos dos fármacos , Compostos Organofosforados/toxicidade , Animais , Reação de Fuga/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Habituação Psicofisiológica/efeitos dos fármacos , Organofosfatos/toxicidade , Reflexo de Sobressalto/efeitos dos fármacos , Comportamento Social , Peixe-Zebra/embriologia
20.
Neurotoxicol Teratol ; 52(Pt B): 210-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26239867

RESUMO

BACKGROUND: FireMaster® 550 (FM 550) is the second most commonly used flame retardant (FR) product in consumer goods and has been detected in household dust samples. However, neurobehavioral effects associated with exposure have not been characterized in detail. We investigated the behavioral effects of FM 550 in zebrafish to facilitate the integration of the cellular and molecular effects of FM 550 with its behavioral consequences. The effects of developmental FM 550 exposure on zebrafish larvae swimming shortly after the end of exposure as well as the persisting effects of this exposure on adolescent behavior were studied. In addition, the acute effects of FM 550 on behavior with exposure during adolescence in zebrafish were studied. METHODS: Developmental exposure to 0, 0.01, 0.1 or 1 mg/L of FM 550 via immersion spanned 0-5 days post fertilization, with larval testing on day 6 and adolescent testing on days 40-45. Acute adolescent (45 dpf) exposure was to 0, 1.0 or 3.0 mg/L of FM 550 via immersion, for 24 h, with testing 2 h or 1 week later. The vehicle condition was colony tank water with .0004% (developmental) or .0012% (adolescent) DMSO. Zebrafish behavior was characterized across several domains including learning, social affiliation, sensorimotor function, predator escape, and novel environment exploration. RESULTS: Persisting effects of developmental FM 550 exposure included a significant (p<0.01) reduction in social behavior among all dose groups. Acute FM 550 exposure during adolescence caused hypoactivity and reduced social behavior (p's<0.05) when the fish were tested 2 h after exposure. These effects were attenuated at the 1 week post exposure testing point DISCUSSION: Taken together, these data indicate that FM 550 may cause persisting neurobehavioral alterations to social behavior in the absence of perturbations along other behavioral domains and that developmental exposure is more costly to the organism than acute adolescent exposure.


Assuntos
Comportamento Animal/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Retardadores de Chama/toxicidade , Organofosfatos/toxicidade , Bifenil Polibromatos/toxicidade , Animais , Reação de Fuga/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Retardadores de Chama/administração & dosagem , Habituação Psicofisiológica/efeitos dos fármacos , Organofosfatos/administração & dosagem , Bifenil Polibromatos/administração & dosagem , Reflexo de Sobressalto/efeitos dos fármacos , Comportamento Social , Peixe-Zebra/embriologia
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