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1.
Acta Biomed ; 94(S1): e2023210, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37490034

RESUMO

Necrotizing fasciitis is a rare soft tissue infection that requires immediate medical attention to prevent its fulminant development that can lead to amputation or death of the patient. In most of reported cases of multifocal necrotizing fasciitis, injuries appear synchronously within hours from the initial diagnosis. It is the only third reported case with metachronous lesions, and the first that involves both S. pyogenes and S. aureus. Early diagnosis and multidisciplinary treatment is mandatory to prevent fatal outcomes. We present the case of a 58-year-old Caucasian man who developed necrotizing fasciitis of both lower limbs with four days between each one. After initial clinical suspicion, he was treated with intravenous antibiotics and we performed an urgent fasciotomy of the right leg and diagnosis was confirmed. Streptococcus pyogenes and Methicillin-Resistant Staphylococcus aureus were isolated from intraoperative cultures. Four days later, due to rising signs on the left limb, another fasciotomy had to be performed and the same microorganisms were isolated. Our patient was discharged home one month after his admission and had no complications during the follow-up. In order to prevent the development of metachronous lesions, early multidisciplinary treatment with aggressive and repeated debridement is necessary. We managed to keep our patient alive, without amputation or intervention by Plastic Surgery, and he recovered fully which is an excellent outcome from a very aggressive disease.


Assuntos
Fasciite Necrosante , Staphylococcus aureus Resistente à Meticilina , Masculino , Humanos , Pessoa de Meia-Idade , Staphylococcus aureus , Extremidade Inferior , Perna (Membro)
2.
Genes (Basel) ; 13(3)2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35328049

RESUMO

While Inherited Retinal Diseases (IRDs) are typically considered rare diseases, Familial Exudative Vitreo-Retinopathy (FEVR) and Norrie Disease (ND) are more rare than retinitis pigmentosa. We wanted to determine if multigenic protein-altering variants are common in FEVR subjects within a set of FEVR-related genes. The potential occurrence of protein-altering variants in two different genes has been documented in a very small percentage of patients, but potential multigenic contributions to FEVR remain unclear. Genes involved in these orphan pediatric retinal diseases are not universally included in available IRD targeted-sequencing panels, and cost is also a factor limiting multigenic-sequence-based testing for these rare conditions. To provide an accurate solution at lower cost, we developed a targeted-sequencing protocol that includes seven genes involved in Familial Exudative Vitreo-Retinopathy (FEVR) and Norrie disease. Seventy-six DNA samples from persons refered to clinic with possible FEVR and some close relatives were sequenced using a novel Oakland-ERI orphan pediatric retinal disease panel (version 2) providing 900 times average read coverage. The seven genes involved in FEVR/ND were: NDP (ChrX), CTNNB1 (Chr3); TSPAN12 (Chr7); KIF11 (Chr10), FZD4 (Chr11), LRP5 (Chr11), ZNF408 (Chr11). A total of 33 variants were found that alter protein sequence, with the following relative distribution: LRP5 13/33 (40%), FZD4 9/33 (27%), ZNF408 6/33 (18%), (KIF11 3/33 (9%), NDP 1/33 (3%), CTNNB1 1/33 (3%). Most protein-altering variants, 85%, were found in three genes: FZD4, LRP5, and ZNF408. Four previously known pathogenic variants were detected in five families and two unrelated individuals. Two novel, likely pathogenic variants were detected in one family (FZD4: Cys450ter), and a likely pathogenic frame shift termination variant was detected in one unrelated individual (LRP5: Ala919CysfsTer67). The average number of genes with protein-altering variants was greater in subjects with confirmed FEVR (1.46, n = 30) compared to subjects confirmed unaffected by FEVR (0.95, n = 20), (p = 0.009). Thirty-four percent of persons sequenced had digenic and trigenic protein-altering variants within this set of FEVR genes, which was much greater than expected in the general population (3.6%), as derived from GnomAD data. While the potential contributions to FEVR are not known for most of the variants in a multigenic context, the high multigenic frequency suggests that potential multigenic contributions to FEVR severity warrant future investigation. The targeted-sequencing format developed will support such exploration by reducing the testing cost to $250 (US) for seven genes and facilitating greater access to genetic testing for families with this very rare inherited retinal disease.


Assuntos
Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Doenças Retinianas , Cegueira/congênito , Criança , Análise Mutacional de DNA , Proteínas de Ligação a DNA/genética , Vitreorretinopatias Exsudativas Familiares/genética , Receptores Frizzled/metabolismo , Doenças Genéticas Ligadas ao Cromossomo X , Humanos , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Mutação , Doenças do Sistema Nervoso , Degeneração Retiniana , Doenças Retinianas/metabolismo , Espasmos Infantis , Tetraspaninas/genética , Tetraspaninas/metabolismo , Fatores de Transcrição/genética
3.
Mol Vis ; 27: 191-205, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33953532

RESUMO

Purpose: There are reports that a b-isoform of vascular endothelial growth factor-A 165 (VEGFA165b) is predominant in normal human vitreous, switching to the a-isoform (VEGFA165a) in the vitreous of some diseased eyes. Although these isoforms appear to have a different ability to activate the VEGF receptor 2 (VEGFR2) in various endothelial cells, the nature of their ability to activate intracellular signaling pathways is not fully characterized, especially in retinal endothelial cells. We determined their activation potential for two key intracellular signaling pathways (MAPK, AKT) over complete dose-response curves and compared potential effects on the expression of several VEGFA165 target genes in primary human retinal microvascular endothelial cells (HRMECs). Methods: To determine full dose-response curves for the activation of MAPK (ERK1/2), AKT, and VEGFR2, direct in-cell western assays were developed using primary HRMECs. Potential differences in dose-response effects on gene expression markers related to endothelial cell and leukocyte adhesion (ICAM1, VCAM1, and SELE) and tight junctions (CLDN5 and OCLN) were tested with quantitative PCR. Results: Activation dose-response analysis revealed much stronger activation of MAPK, AKT, and VEGFR2 by the a-isoform at lower doses. MAPK activation in primary HRMECs displayed a sigmoidal dose-response to a range of VEGFA 165 a concentrations spanning 10-250 pM, which shifted higher into the 100-5,000 pM range with VEGFA 165 b. Similar maximum activation of MAPK was achieved by both isoforms at high concentrations. Maximum activation of AKT by VEGFA 165 b was only half of the maximum activation from VEGFA 165 a. At a lower intermediate dose, where VEGFA 165 a activated intracellular signaling stronger than VEGFA 165 b, the changes in VEGFA target gene expression were generally greater with VEGFA 165 a. Conclusions: In primary HRMECs, VEGFA 165 a could maximally activate MAPK and AKT at lower concentrations where VEGFA 165 b had relatively little effect. The timing for maximum activation of MAPK was similar for the isoforms, which is different from that reported for non-retinal endothelial cells. Although differences in VEGFA 165 a and VEGFA 165 b are limited to the sequence of their six C-terminal six amino acids, this results in a large difference in their ability to activate at least two key intracellular signaling pathways and VEGF-target gene expression in primary human retinal endothelial cells.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Vasos Retinianos/citologia , Transdução de Sinais/fisiologia , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Claudina-5/genética , Selectina E/genética , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica/fisiologia , Humanos , Immunoblotting , Molécula 1 de Adesão Intercelular/genética , Ocludina/genética , Reação em Cadeia da Polimerase , Isoformas de Proteínas , Ativação Transcricional/fisiologia , Molécula 1 de Adesão de Célula Vascular/genética
4.
Sci Adv ; 7(10)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658192

RESUMO

Neurons synaptically interacting in a conductive medium generate extracellular endogenous electric fields (EFs) that reciprocally affect membrane potential. Exogenous EFs modulate neuronal activity, and their clinical applications are being profusely explored. However, whether endogenous EFs contribute to network synchronization remains unclear. We analyzed spontaneously generated slow-wave activity in the cerebral cortex network in vitro, which allowed us to distinguish synaptic from nonsynaptic mechanisms of activity propagation and synchronization. Slow oscillations generated EFs that propagated independently of synaptic transmission. We demonstrate that cortical oscillations modulate spontaneous rhythmic activity of neighboring synaptically disconnected cortical columns if layers are aligned. We provide experimental evidence that these EF-mediated effects are compatible with electric dipoles. With a model of interacting dipoles, we reproduce the experimental measurements and predict that endogenous EF-mediated synchronizing effects should be relevant in the brain. Thus, experiments and models suggest that electric-dipole interactions contribute to synchronization of neighboring cortical columns.

5.
Neuroimage ; 224: 117415, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33011419

RESUMO

The ability of different groups of cortical neurons to engage in causal interactions that are at once differentiated and integrated results in complex dynamic patterns. Complexity is low during periods of unconsciousness (deep sleep, anesthesia, unresponsive wakefulness syndrome) in which the brain tends to generate a stereotypical pattern consisting of alternating active and silent periods of neural activity-slow oscillations- and is high during wakefulness. But how is cortical complexity built up? Is it a continuum? An open question is whether cortical complexity can vary within the same brain state. Here we recorded with 32-channel multielectrode arrays from the cortical surface of the mouse and used both spontaneous dynamics (wave propagation entropy and functional complexity) and a perturbational approach (a variation of the perturbation complexity index) to measure complexity at different anesthesia levels. Variations in anesthesia level within the bistable regime of slow oscillations (0.1-1.5 Hz) resulted in a modulation of the slow oscillation frequency. Both perturbational and spontaneous complexity increased with decreasing anesthesia levels, in correlation with the decrease in coherence of the underlying network. Changes in complexity level are related to, but not dependent on, changes in excitability. We conclude that cortical complexity can vary within a single brain state dominated by slow oscillations, building up to the higher complexity associated with consciousness.


Assuntos
Anestésicos Gerais/farmacologia , Ondas Encefálicas/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Anestesia Geral , Animais , Ondas Encefálicas/fisiologia , Córtex Cerebral/fisiologia , Estimulação Elétrica , Eletroencefalografia , Hipnóticos e Sedativos/farmacologia , Isoflurano/farmacologia , Ketamina/farmacologia , Medetomidina/farmacologia , Camundongos
6.
Mol Neurobiol ; 57(2): 765-777, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31471877

RESUMO

Williams-Beuren syndrome (WBS) is a rare neurodevelopmental disorder characterized by moderate intellectual disability and learning difficulties alongside behavioral abnormalities such as hypersociability. Several structural and functional brain alterations are characteristic of this syndrome, as well as disturbed sleep and sleeping patterns. However, the detailed physiological mechanisms underlying WBS are mostly unknown. Here, we characterized the cortical dynamics in a mouse model of WBS previously reported to replicate most of the behavioral alterations described in humans. We recorded the laminar local field potential generated in the frontal cortex during deep anesthesia and characterized the properties of the emergent slow oscillation activity. Moreover, we performed micro-electrocorticogram recordings using multielectrode arrays covering the cortical surface of one hemisphere. We found significant differences between the cortical emergent activity and functional connectivity between wild-type mice and WBS model mice. Slow oscillations displayed Up states with diminished firing rate and lower high-frequency content in the gamma range. Lower firing rates were also recorded in the awake WBS animals while performing a marble burying task and could be associated with the decreased spine density and thus synaptic connectivity in this cortical area. We also found an overall increase in functional connectivity between brain areas, reflected in lower clustering and abnormally high integration, especially in the gamma range. These results expand previous findings in humans, suggesting that the cognitive deficits characterizing WBS might be associated with reduced excitability, plus an imbalance in the capacity to functionally integrate and segregate information.


Assuntos
Neocórtex/patologia , Síndrome de Williams/patologia , Animais , Espinhas Dendríticas/metabolismo , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Neocórtex/fisiopatologia , Rede Nervosa/patologia , Rede Nervosa/fisiopatologia , Vigília , Síndrome de Williams/fisiopatologia
7.
Data Brief ; 15: 491-495, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29062875

RESUMO

The data presented in this article are related to the research paper entitled "Norrin treatment improves ganglion cell survival in an oxygen-induced model of retinal ischemia" (Dailey et al., 2017) [1] This article describes treatment with the human Norrin protein, an atypical Wnt-protein, to improve the survival of retinal ganglion cells in a murine model of Oxygen-Induced Retinopathy (OIR). That study utilized Optical coherence tomography (OCT) to visualize retinal layers at high resolution in vivo, and to quantify changes to nerve fiber layer thickness. Organization of the laminar structure of other retinal layers in this model in vivo, were not known because of uncertainties regarding potential artifacts during the processing of tissue for traditional histology. The OCT image data provided here shows researchers the retinal laminar structural features that exist in vivo in this popular mouse OIR model. Traditional H&E stained retinal tissue sections are also provided here for comparison.

8.
Exp Eye Res ; 164: 129-138, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28823941

RESUMO

Treatment of a mouse model of oxygen-induced retinopathy (OIR) with recombinant human Norrin (Norrie Disease Protein, gene: NDP) accelerates regrowth of the microvasculature into central ischemic regions of the neural retina, which are generated after treatment with 75% oxygen. While this reduces the average duration and severity of ischemia overall, we do not know if this accelerated recovery of the microvasculature results in any significant survival of retinal ganglion cells (RGCs). The purpose of this study was to investigate ganglion cell survival with and without the intravitreal injection of Norrin in the murine model of oxygen induced retinopathy (OIR), using two strains of mice: C57BL/6J and Thy1-YFP mice. Intravitreal injections of Norrin or vehicle were done after five days of exposure to 75% oxygen from ages P7 to P12. The C57BL/J mice were followed by Spectral-Domain Optical Coherence Tomography (SD-OCT), and the average nerve fiber layer (NFL) and inner-plexiform layer (IPL) thicknesses were measured at twenty-four locations per retina at P42. Additionally, some C57BL/J retinas were flat mounted and immunostained for the RGC marker, Brn3a, to compare the population density of surviving retinal ganglion cells. Using homozygous Thy1-YFP mice, single intrinsically fluorescent RGCs were imaged in live animals with a Micron-III imaging system at ages P21, 28 and P42. The relative percentage of YFP-fluorescent RGCs with dendritic arbors were compared. At age P42, the NFL was thicker in Norrin-injected OIR eyes, 14.4 µm, compared to Vehicle-injected OIR eyes, 13.3 µm (p = 0.01). In the superior retina, the average thickness of the IPL was greater in Norrin-injected OIR eyes, 37.7 µm, compared to Vehicle-injected OIR eyes, 34.6 µm (p = 0.04). Retinas from Norrin injected OIR mice had significantly more surviving RGCs (p = 0.03) than vehicle-injected mice. Based upon NFL thickness and counts of RGCs, we conclude that Norrin treatment, early in the ischemic phase, increased the relative population density of surviving RGCs in the central retinas of OIR mice.


Assuntos
Proteínas do Olho/farmacologia , Proteínas do Tecido Nervoso/farmacologia , Retina/patologia , Células Ganglionares da Retina/efeitos dos fármacos , Neovascularização Retiniana/tratamento farmacológico , Animais , Sobrevivência Celular , Modelos Animais de Doenças , Humanos , Isquemia/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Oxigênio/farmacologia , Retina/metabolismo , Células Ganglionares da Retina/patologia , Vasos Retinianos/metabolismo , Fator de Transcrição Brn-3A/metabolismo
9.
Environ Sci Technol ; 50(13): 6803-13, 2016 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-26992352

RESUMO

Limited supply of clean water in urbanizing watersheds creates challenges for safely sustaining irrigated agriculture and global food security. On-farm interventions, such as riverbank filtration (RBF), are used in developing countries to treat irrigation water from rivers with extensive fecal contamination. Using a Bayesian approach incorporating ethnographic data and pathogen measurements, quantitative microbial risk assessment (QMRA) methods were employed to assess the impact of RBF on consumer health burdens for Giardia, Cryptosporidium, rotavirus, norovirus, and adenovirus infections resulting from indirect wastewater reuse, with lettuce irrigation in Bolivia as a model system. Concentrations of the microbial source tracking markers pepper mild mottle virus and HF183 Bacteroides were respectively 2.9 and 5.5 log10 units lower in RBF-treated water than in the river water. Consumption of lettuce irrigated with river water caused an estimated median health burden that represents 37% of Bolivia's overall diarrheal disease burden, but RBF resulted in an estimated health burden that is only 1.1% of this overall diarrheal disease burden. Variability and uncertainty associated with environmental and cultural factors affecting exposure correlated more with QMRA-predicted health outcomes than factors related to disease vulnerability. Policies governing simple on-farm interventions like RBF can be intermediary solutions for communities in urbanizing watersheds that currently lack wastewater treatment.


Assuntos
Teorema de Bayes , Águas Residuárias/virologia , Irrigação Agrícola , Giardia , Humanos , Norovirus , Medição de Risco
10.
Mol Vis ; 20: 1527-44, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25489226

RESUMO

PURPOSE: The histone-deacetylase inhibitor activity of valproic acid (VPA) was discovered after VPA's adoption as an anticonvulsant. This generated speculation for VPA's potential to increase the expression of neuroprotective genes. Clinical trials for retinitis pigmentosa (RP) are currently active, testing VPA's potential to reduce photoreceptor loss; however, we lack information regarding the effects of VPA on available mammalian models of retinal degeneration, nor do we know if retinal gene expression is perturbed by VPA in a predictable way. Thus, we examined the effects of systemic VPA on neurotrophic factor and Nrl-related gene expression in the mouse retina and compared VPA's effects on the rate of photoreceptor loss in two strains of mice, Pde6b(rd1/rd1) and Pde6b(rd10/rd10) . METHODS: The expression of Bdnf, Gdnf, Cntf, and Fgf2 was measured by quantitative PCR after single and multiple doses of VPA (intraperitoneal) in wild-type and Pde6b(rd1/rd1) mice. Pde6b(rd1/rd1) mice were treated with daily doses of VPA during the period of rapid photoreceptor loss. Pde6b(rd10/rd10) mice were also treated with systemic VPA to compare in a partial loss-of-function model. Retinal morphology was assessed by virtual microscopy or spectral-domain optical coherence tomography (SD-OCT). Full-field and focal electroretinography (ERG) analysis were employed with Pde6b(rd10/rd10) mice to measure retinal function. RESULTS: In wild-type postnatal mice, a single VPA dose increased the expression of Bdnf and Gdnf in the neural retina after 18 h, while the expression of Cntf was reduced by 70%. Daily dosing of wild-type mice from postnatal day P17 to P28 resulted in smaller increases in Bdnf and Gdnf expression, normal Cntf expression, and reduced Fgf2 expression (25%). Nrl gene expression was decreased by 50%, while Crx gene expression was not affected. Rod-specific expression of Mef2c and Nr2e3 was decreased substantially by VPA treatment, while Rhodopsin and Pde6b gene expression was normal at P28. Daily injections with VPA (P9-P21) dramatically slowed the loss of rod photoreceptors in Pde6b(rd1/rd1) mice. At age P21, VPA-treated mice had several extra rows of rod photoreceptor nuclei compared to PBS-injected littermates. Dosing started later (P14) or dosing every second day also rescued photoreceptors. In contrast, systemic VPA treatment of Pde6b(rd10/rd10) mice (P17-P28) reduced visual function that correlated with a slight increase in photoreceptor loss. Treating Pde6b(rd10/rd10) mice earlier (P9-P21) also failed to rescue photoreceptors. Treating wild-type mice earlier (P9-P21) reduced the number of photoreceptors in VPA-treated mice by 20% compared to PBS-treated animals. CONCLUSIONS: A single systemic dose of VPA can change retinal neurotrophic factor and rod-specific gene expression in the immature retina. Daily VPA treatment from P17 to P28 can also alter gene expression in the mature neural retina. While daily treatment with VPA could significantly reduce photoreceptor loss in the rd1 model, VPA treatment slightly accelerated photoreceptor loss in the rd10 model. The apparent rescue of photoreceptors in the rd1 model was not the result of producing more photoreceptors before degeneration. In fact, daily systemic VPA was toxic to wild-type photoreceptors when started at P9. However, the effective treatment period for Pde6b(rd1/rd1) mice (P9-P21) has significant overlap with the photoreceptor maturation period, which complicates the use of the rd1 model for testing of VPA's efficacy. In contrast, VPA treatment started after P17 did not cause photoreceptor loss in wild-type mice. Thus, the acceleration of photoreceptor loss in the rd10 model may be more relevant where both photoreceptor loss and VPA treatment (P17-P28) started when the central retina was mature.


Assuntos
Inibidores Enzimáticos/farmacologia , Substâncias Protetoras/farmacologia , Degeneração Retiniana/tratamento farmacológico , Células Fotorreceptoras Retinianas Bastonetes/efeitos dos fármacos , Ácido Valproico/farmacologia , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 6/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 6/metabolismo , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Regulação da Expressão Gênica , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Injeções Intraperitoneais , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Receptores Nucleares Órfãos/genética , Receptores Nucleares Órfãos/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/patologia , Rodopsina/genética , Rodopsina/metabolismo , Especificidade da Espécie , Fatores de Tempo , Transativadores/genética , Transativadores/metabolismo
11.
Front Public Health ; 2: 69, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25101253

RESUMO

Despite increased interest regarding the potentially long-term negative impact of chronic traumatic brain injury, limited research has been conducted regarding such injuries and neurological outcomes in real world settings. To increase understanding regarding the relationship between sparring (e.g., training under the tutelage of an experienced boxing coach for the purpose of improving skills and/or fitness) and neurological functioning, professional boxers (n = 237) who competed in Maryland between 2003 and 2008 completed measures regarding sparring exposure (Cumulative Sparring Index, CSI) and performance on tests of cognition (Symbol Digit Modalities Test, SDMT) and balance (Sharpened Romberg Test, SRT). Measures were completed prior to boxing matches. Higher scores on the CSI (increased sparring exposure) were associated with poorer performance on both tests of cognition (SDMT) and balance (SRT). A threshold effect was noted regarding performance on the SDMT, with those reporting CSI values greater than about 150 experiencing a decline in cognition. A history of frequent and/or intense sparring may pose a significant risk for developing boxing associated neurological sequelae. Implementing administration of clinically meaningful tests before bouts, such as the CSI, SDMT, and/or the SRT, as well as documentation of results into the boxer's physicals or medical profiles may be an important step for improving boxing safety.

12.
Nanoscale Res Lett ; 9(1): 36, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24438542

RESUMO

An extensive study on molecular beam epitaxy growth conditions of quaternary GaAsSbN as a capping layer (CL) for InAs/GaAs quantum dots (QD) was carried out. In particular, CL thickness, growth temperature, and growth rate were optimized. Problems related to the simultaneous presence of Sb and N, responsible for a significant degradation of photoluminescence (PL), are thereby solved allowing the achievement of room-temperature (RT) emission. A particularly strong improvement on the PL is obtained when the growth rate of the CL is increased. This is likely due to an improvement in the structural quality of the quaternary alloy that resulted from reduced strain and composition inhomogeneities. Nevertheless, a significant reduction of Sb and N incorporation was found when the growth rate was increased. Indeed, the incorporation of N is intrinsically limited to a maximum value of approximately 1.6% when the growth rate is at 2.0 ML s-1. Therefore, achieving RT emission and extending it somewhat beyond 1.3 µm were possible by means of a compromise among the growth conditions. This opens the possibility of exploiting the versatility on band structure engineering offered by this QD-CL structure in devices working at RT. PACS: 81.15.Hi (molecular beam epitaxy); 78.55.Cr (III-V semiconductors); 73.21.La (quantum dots).

13.
Phys Rev Lett ; 109(12): 126101, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-23005962

RESUMO

We experimentally demonstrate a sigmoidal variation of the composition profile across semiconductor heterointerfaces. The wide range of material systems (III-arsenides, III-antimonides, III-V quaternary compounds, III-nitrides) exhibiting such a profile suggests a universal behavior. We show that sigmoidal profiles emerge from a simple model of cooperative growth mediated by two-dimensional island formation, wherein cooperative effects are described by a specific functional dependence of the sticking coefficient on the surface coverage. Experimental results confirm that, except in the very early stages, island growth prevails over nucleation as the mechanism governing the interface development and ultimately determines the sigmoidal shape of the chemical profile in these two-dimensional-grown layers. In agreement with our experimental findings, the model also predicts a minimum value of the interfacial width, with the minimum attainable value depending on the chemical identity of the species.

14.
Appl Environ Microbiol ; 78(15): 5133-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22582051

RESUMO

Viable ova of Ascaris lumbricoides, an indicator organism for pathogens, are frequently found in feces-derived compost produced from ecological toilets, demonstrating that threshold levels of time, temperature, pH, and moisture content for pathogen inactivation are not routinely met. Previous studies have determined that NH(3) has ovicidal properties for pathogens, including Ascaris ova. This research attempted to achieve Ascaris inactivation via NH(3) under environmental conditions commonly found in ecological toilets and using materials universally available in an ecological sanitation setting, including compost (feces and sawdust), urine, and ash. Compost mixed with stored urine and ash produced the most rapid inactivation, with significant inactivation observed after 2 weeks and with a time to 99% ovum inactivation (T(99)) of 8 weeks. Compost mixed with fresh urine and ash achieved a T(99) of 15 weeks, after a 4-week lag phase. Both matrices had relatively high total-ammonia concentrations and pH values of >9.24 (pK(a) of ammonia). In compost mixed with ash only, and in compost mixed with fresh urine only, inactivation was observed after an 11-week lag phase. These matrices contained NH(3) concentrations of 164 to 173 and 102 to 277 mg/liter, respectively, when inactivation occurred, which was below the previously hypothesized threshold for inactivation (280 mg/liter), suggesting that a lower threshold NH(3) concentration may be possible with a longer contact time. Other significant results include the hydrolysis of urea to ammonia between pH values of 10.4 and 11.6, above the literature threshold pH of 10.


Assuntos
Amônia/toxicidade , Ascaris/fisiologia , Fezes/parasitologia , Óvulo/efeitos dos fármacos , Engenharia Sanitária/métodos , Animais , Ascaris/efeitos dos fármacos , Bolívia , Fezes/química , Humanos , Modelos Lineares , Fatores de Tempo , Banheiros , Urina/química
15.
Bipolar Disord ; 14(1): 90-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22329476

RESUMO

OBJECTIVE: An association between allergic disease and depression has been consistently reported, but whether the key mediating ingredients are predominantly biological, psychological, or mere artifacts remains unknown. In the current study, we examined a hypothesized relationship between allergen-specific immunoglobulin E (IgE) status and changes in allergy symptoms with worsening in depression scores. METHODS: In patients with recurrent mood disorders, we individually coupled sensitization to specific seasonal aeroallergens (as assessed by allergen-specific IgE) with temporal windows of exposure to aeroallergens (low versus high tree or ragweed pollen counts, measured according to the National Allergy Bureau guidelines). We compared Structured Interview Guide for the Hamilton Depression Rating Scale-Seasonal Affective Disorder Version (SIGH-SAD) depression score changes in 41 patients with mood disorders [25 with major depression and 16 with bipolar I disorder, diagnosed by Structured Clinical Interview for DSM (SCID)] seropositive for tree or ragweed pollen-specific IgE antibody versus 53 patients with mood disorders (30 with major depression and 23 with bipolar I disorder) seronegative for aeroallergen-specific IgE. RESULTS: Worsening in total depressive scores from low to high pollen exposure was greater in allergen-specific IgE-positive patients as compared to allergen-specific IgE antibody-negative patients (p = 0.01). When stratified by polarity, the association was significant only in patients with bipolar I disorder (p = 0.004). This relationship was resilient to adjustment for changes in allergy symptom scores. CONCLUSION: To our knowledge, this is the first report of coupling a molecular marker of vulnerability (allergen-specific IgE) with a specific environmental trigger (airborne allergens) leading to exacerbation of depression in patients with bipolar I disorder.


Assuntos
Alérgenos/imunologia , Transtorno Bipolar/imunologia , Depressão/imunologia , Imunoglobulina E/sangue , Pólen/imunologia , Rinite Alérgica Sazonal/psicologia , Adulto , Ambrosia/imunologia , Transtorno Bipolar/psicologia , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estações do Ano , Índice de Gravidade de Doença , Árvores/imunologia
17.
Int J Adolesc Med Health ; 21(4): 431-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20306758

RESUMO

The multicultural nature of American society presents clinicians and mental health providers with the unique challenge of working with mentally ill patients from many different cultural backgrounds. Although research investigating suicidal behavior among Latinos is limited, the literature suggests the presence of two distinct phenomena: (a) the prevalence of completed suicide among Latinos as a group is lower than the national rate and (b) the prevalence of suicidal behavior among Latino youth between the ages of 10-24 years is greater than in other ethnic groups, especially among females. Acculturation, family conflicts, physical abuse and sexual abuse, among other factors, have been suggested to increase the risk of depression and suicide among young Latinos. To ameliorate suicidal behavior among Latino youth, more research is needed about specific risk factors, diagnosis, treatment, and ultimately, suicide prevention. Research focused on identifying risk and mediating factors for suicidal behavior in young Latinos is particularly relevant, given the size and rapid growth of the Latino population in the United States of America.


Assuntos
Hispânico ou Latino/estatística & dados numéricos , Suicídio/etnologia , Aculturação , Adolescente , Comportamento do Adolescente , Adulto , Criança , Depressão/etnologia , Relações Familiares/etnologia , Humanos , Saúde Mental/estatística & dados numéricos , Prevalência , Grupos Raciais , Religião , Distribuição por Sexo , Delitos Sexuais , Adulto Jovem
18.
Int J Child Health Hum Dev ; 1(3): 313-322, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19430577

RESUMO

Considering clinical and animal evidence suggesting a relationship between allergy and anxiety, we hypothesized that, from low to high aeroallergen exposure, changes in anxiety symptom scores in patients with primary mood disorders will correlate with changes in allergy symptom scores. We also anticipated that sensitization to tree pollen, as determined by allergen specific IgE antibodies, will predict a greater worsening of anxiety during exposure to tree pollen. 51 patients with unipolar or bipolar disorder (age: 19-63 years, 65% female) were recruited. Tree- pollen IgE positive subjects (12) were included as the experimental group and patients negative to a multi-allergen serological test (39) were included in the control group. Self reports of anxiety and allergy symptoms were obtained once during the peak airborne pollen counts and once during the period of low airborne pollen counts, as reported by two local pollen counting stations. Using linear regression models, we confirmed a significant positive association between allergy scores and anxiety scores (p<0.04); however, the IgE specific tree pollen positivity was not significantly associated with changes in anxiety scores. Because changes in anxiety scores relate to changes in depression scores, the relationship between allergy and anxiety involves states rather than only traits, and as such, our results lead to future efforts to uncover potential anxiety triggering, exacerbating or perpetuating role of allergens in vulnerable individuals.

19.
ScientificWorldJournal ; 7: 870-9, 2007 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-17619773

RESUMO

To our knowledge, this paper is the first to estimate seasonality of mood in a predominantly Caucasian sample, living in areas with hot summers and a relative unavailability of air conditioning. As a summer pattern of seasonal depression was previously associated with a vulnerability to heat exposure, we hypothesized that those with access to air conditioners would have a lower rate of summer seasonal affective disorder (SAD) compared to those without air conditioning. A convenience sample of 476 Romanian postgraduate students completed the Seasonal Pattern Assessment Questionnaire (SPAQ), which was used to calculate a global seasonality score (GSS) and to estimate the rates of winter- and summer-type SAD. The ratio of summer- vs. winter-type SAD was compared using multinomial probability distribution tests. We also compared the ratio of summer SAD in individuals with vs. without air conditioners. Winter SAD and winter subsyndromal SAD (S-SAD) were significantly more prevalent than summer SAD and summer S-SAD. Those with access to air conditioners had a higher, rather than a lower, rate of summer SAD. Our results are consistent with prior studies that reported a lower prevalence of summer than winter SAD in Caucasian populations. Finding an increased rate of summer SAD in the minority of those with access to air conditioners was surprising and deserves replication.


Assuntos
Ar Condicionado/estatística & dados numéricos , Educação de Pós-Graduação em Medicina/estatística & dados numéricos , Transtornos Mentais/epidemiologia , Medição de Risco/métodos , Transtorno Afetivo Sazonal/epidemiologia , Estações do Ano , Estudantes de Medicina/estatística & dados numéricos , Adulto , Distribuição por Idade , Comorbidade , Feminino , Humanos , Incidência , Masculino , Fatores de Risco , Romênia/epidemiologia , Distribuição por Sexo
20.
ScientificWorldJournal ; 7: 577-83, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17525822

RESUMO

We conducted a prospective, longitudinal study of seasonality in a vulnerable population, i.e., African students who migrated to a temperate climate. Consistent with previous cross-sectional studies, we hypothesized lower mood and energy, and higher appetite and weight, in fall/winter than in spring/summer. Four cohorts of African students attending a year-long nursing school program without vacation in Washington, D.C., were assessed monthly for 1 year. Forty-three subjects (mean age = 33.46 +/- 6.25), consisting of predominantly females (76.7%), completed the study. The cohorts began their academic program in different seasons (one each in winter, spring, summer, and fall), inherently minimizing confounding influences on seasonality, such as academic and immigration stress, as well as allowing adjustment for an order effect. At each assessment, students completed three 100-mm visual analog scales for mood, energy, and appetite, and were weighed on a digital scale. For each standardized dependent variable, a repeated measure ANOVA was used and, if a significant effect of month was identified, averages for spring/summer and fall/winter were compared using paired t-tests. In addition, a mixed model for repeated measures was applied to raw (nonstandardized) data. Body weight was significantly higher in fall/winter than in spring/summer (p < 0.01). No seasonal differences in mood, energy, or appetite were found. Benefiting from certain unique features of our cohorts allowing adjustment for order effects, this is the first study to identify a seasonal variation in body weight with a peak in winter using longitudinal monthly measurements.


Assuntos
População Negra/psicologia , População Negra/estatística & dados numéricos , Emigração e Imigração , Estações do Ano , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Adulto , África/etnologia , District of Columbia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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