Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 119
Filtrar
1.
Phys Rev Lett ; 132(15): 155102, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38683000

RESUMO

We present the first experimental study of plasmoid formation in a magnetic reconnection layer undergoing rapid radiative cooling, a regime relevant to extreme astrophysical plasmas. Two exploding aluminum wire arrays, driven by the Z machine, generate a reconnection layer (S_{L}≈120) in which the cooling rate far exceeds the hydrodynamic transit rate (τ_{hydro}/τ_{cool}>100). The reconnection layer generates a transient burst of >1 keV x-ray emission, consistent with the formation and subsequent rapid cooling of the layer. Time-gated x-ray images show fast-moving (up to 50 km s^{-1}) hotspots in the layer, consistent with the presence of plasmoids in 3D resistive magnetohydrodynamic simulations. X-ray spectroscopy shows that these hotspots generate the majority of Al K-shell emission (around 1.6 keV) prior to the onset of cooling, and exhibit temperatures (170 eV) much greater than that of the plasma inflows and the rest of the reconnection layer, thus providing insight into the generation of high-energy radiation in radiatively cooled reconnection events.

2.
Genet Med ; 23(4): 645-652, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33244165

RESUMO

PURPOSE: MED12 is a subunit of the Mediator multiprotein complex with a central role in RNA polymerase II transcription and regulation of cell growth, development, and differentiation. This might underlie the variable phenotypes in males carrying missense variants in MED12, including X-linked recessive Ohdo, Lujan, and FG syndromes. METHODS: By international matchmaking we assembled variant and clinical data on 18 females presenting with variable neurodevelopmental disorders (NDDs) and harboring de novo variants in MED12. RESULTS: Five nonsense variants clustered in the C-terminal region, two splice variants were found in the same exon 8 splice acceptor site, and 11 missense variants were distributed over the gene/protein. Protein truncating variants were associated with a severe, syndromic phenotype consisting of intellectual disability (ID), facial dysmorphism, short stature, skeletal abnormalities, feeding difficulties, and variable other abnormalities. De novo missense variants were associated with a less specific, but homogeneous phenotype including severe ID, autistic features, limited speech and variable other anomalies, overlapping both with females with truncating variants as well as males with missense variants. CONCLUSION: We establish de novo truncating variants in MED12 as causative for a distinct NDD and de novo missense variants as causative for a severe, less specific NDD in females.


Assuntos
Deficiência Intelectual , Complexo Mediador/genética , Deficiência Intelectual Ligada ao Cromossomo X , Transtornos do Neurodesenvolvimento , Feminino , Genes Ligados ao Cromossomo X , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual Ligada ao Cromossomo X/genética , Mutação de Sentido Incorreto , Transtornos do Neurodesenvolvimento/genética , Fenótipo , Síndrome
3.
Langmuir ; 37(1): 499-508, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33372781

RESUMO

To assess the feasibility of utilizing reagent-loaded, porous polymeric nanocapsules (NCs) for chemical and biochemical sensor design, the surfaces of the NCs were decorated with 3,4-ethylenedioxythiophene (EDOT) moieties. The pores in the capsule wall allow unhindered bidirectional diffusion of molecules smaller than the programmed pore sizes, while larger molecules are either entrapped inside or blocked from entering the interior of the nanocapsules. Here, we investigate two electrochemical deposition methods to covalently attach acrylate-based porous nanocapsules with 3,4-ethylenedioxythiophene moieties on the nanocapsule surface, i.e., EDOT-decorated NCs to the surface of an existing PEDOT film: (1) galvanostatic or bilayer deposition with supporting EDOT in the deposition solution and (2) potentiostatic deposition without supporting EDOT in the deposition solution. The distribution of the covalently attached NCs in the PEDOT films was studied by variable angle FTIR-ATR and XPS depth profiling. The galvanostatic deposition of EDOT-decorated NCs over an existing PEDOT (tetrakis(pentafluorophenyl)borate) [PEDOT(TPFPhB)] film resulted in a bilayer structure, with an interface between the NC-free and NC-loaded layers, that could be traced with variable angle FTIR-ATR measurements. In contrast, the FTIR-ATR and XPS analyses of the films deposited potentiostatically from a solution without EDOT and containing only the EDOT-decorated NCs showed small amounts of NCs in the entire cross section of the films.

4.
J Comput Aided Mol Des ; 34(10): 1027-1044, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32737667

RESUMO

G protein-coupled receptors (GPCR) comprise the largest family of membrane proteins and are of considerable interest as targets for drug development. However, many GPCR structures remain unsolved. To address the structural ambiguity of these receptors, computational tools such as homology modeling and loop modeling are often employed to generate predictive receptor structures. Here we combined both methods to benchmark a protocol incorporating homology modeling based on a locally selected template and extracellular loop modeling that additionally evaluates the presence of template ligands during these modeling steps. Ligands were also docked using three docking methods and two pose selection methods to elucidate an optimal ligand pose selection method. Results suggest that local template-based homology models followed by loop modeling produce more accurate and predictive receptor models than models produced without loop modeling, with decreases in average receptor and ligand RMSD of 0.54 Å and 2.91 Å, respectively. Ligand docking results showcased the ability of MOE induced fit docking to produce ligand poses with atom root-mean-square deviation (RMSD) values at least 0.20 Å lower (on average) than the other two methods benchmarked in this study. In addition, pose selection methods (software-based scoring, ligand complementation) selected lower RMSD poses with MOE induced fit docking than either of the other methods (averaging at least 1.57 Å lower), indicating that MOE induced fit docking is most suited for docking into GPCR homology models in our hands. In addition, target receptor models produced with a template ligand present throughout the modeling process most often produced target ligand poses with RMSD values ≤ 4.5 Å and Tanimoto coefficients > 0.6 after selection based on ligand complementation than target receptor models produced in the absence of template ligands. Overall, the findings produced by this study support the use of local template homology modeling in combination with de novo ECL2 modeling in the presence of a ligand from the template crystal structure to generate GPCR models intended to study ligand binding interactions.


Assuntos
Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Software , Benchmarking , Humanos , Ligantes , Ligação Proteica , Conformação Proteica
5.
Clin Exp Immunol ; 192(3): 251-258, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29431870

RESUMO

Individuals with type 1 diabetes (T1D) are at increased risk of coeliac disease (CD), autoimmune thyroiditis and autoimmune gastritis, but the absolute risks are unclear. The aim of this study was to investigate the prevalence of autoantibodies to tissue transglutaminase (TGA), thyroid peroxidase (TPOA) and gastric H+ /K+ -ATPase (ATPA) and their genetic associations in a well-characterized population-based cohort of individuals with T1D from the Bart's-Oxford family study for whom islet autoantibody prevalence data were already available. Autoantibodies in sera from 1072 patients (males/females 604/468; median age 11·8 years, median T1D duration 2·7 months) were measured by radioimmunoassays; HLA class II risk genotype was analysed in 973 (91%) using polymerase chain reaction with sequence specific primers (PCR-SSP). The prevalence of TGA (and/or history of CD), TPOA and ATPA in patients was 9·0, 9·6 and 8·2%, respectively; 3·1% had two or more autoantibodies. Females were at higher risk of multiple autoimmunity; TGA/CD were associated with younger age and TPOA with older age. ATPA were uncommon in patients under 5 years, and more common in older patients. Anti-glutamate decarboxylase autoantibodies were predictive of co-existing TPOA/ATPA. TGA/CD were associated with human leucocyte antigen (HLA) DR3-DQ2, with the DR3-DQ2/DR3-DQ2 genotype conferring the highest risk, followed by DR4-DQ8/DR4-DQ8. ATPA were associated with DR3-DQ2, DRB1*0404 (in males) and the DR3-DQ2/DR4-DQ8 genotype. TPOA were associated with the DR3-DQ2/DR3-DQ2 genotype. Almost one-quarter of patients diagnosed with T1D aged under 21 years have at least one other organ-specific autoantibody. HLA class II genetic profiling may be useful in identifying those at risk of multiple autoimmunity.


Assuntos
Autoanticorpos/imunologia , Autoantígenos/imunologia , Autoimunidade/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Proteínas de Ligação ao GTP/imunologia , Glutamato Descarboxilase/imunologia , ATPase Trocadora de Hidrogênio-Potássio/imunologia , Iodeto Peroxidase/imunologia , Proteínas de Ligação ao Ferro/imunologia , Transglutaminases/imunologia , Adolescente , Adulto , Doença Celíaca/genética , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença/genética , Antígenos HLA-DQ/genética , Antígeno HLA-DR3/genética , Humanos , Lactente , Masculino , Proteína 2 Glutamina gama-Glutamiltransferase , Radioimunoensaio , Gastropatias/genética , Doenças da Glândula Tireoide/genética , Reino Unido , Adulto Jovem
6.
Diabet Med ; 35(7): 954-963, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29577424

RESUMO

AIMS: Glutamate decarboxylase (GAD) antibodies are the most widely used predictive marker for Type 1 diabetes, but many individuals currently found to be GAD antibody-positive are unlikely to develop diabetes. We have shown previously that radioimmunoassays using N-terminally truncated 35 S-GAD65 (96-585) offer better disease specificity with similar sensitivity to full-length 35 S-GAD65 (1-585). To determine whether assay performance could be improved further, we evaluated a more radically truncated 35 S-GAD65 (143-585) radiolabel. METHODS: Samples from people with recent-onset Type 1 diabetes (n = 157) and their first-degree relatives (n = 745) from the Bart's-Oxford family study of childhood diabetes were measured for GAD antibodies using 35 S-labelled GAD65 (143-585). These were screened previously using a local radioimmunoassay with 35 S-GAD65 (1-585). A subset was also tested by enzyme-linked immunosorbent assay (ELISA), which performs well in international workshops, but requires 10 times more serum. Results were compared with GAD antibody measurements using 35 S-GAD65 (1-585) and 35 S-GAD65 (96-585). RESULTS: Sensitivity of GAD antibody measurement was maintained using 35 S-GAD65 (143-585) compared with 35 S-GAD65 (1-585) and 35 S-GAD65 (96-585). Specificity for Type 1 diabetes was improved compared with 35 S-GAD65 (1-585), but was similar to 35 S-GAD65 (96-585). Relatives found to be GAD antibody-positive using these truncated labels were at increased risk of diabetes progression within 15 years, compared with those positive for GAD(1-585) antibody only, and at similar risk to those found GAD antibody-positive by ELISA. CONCLUSIONS: The first 142 amino acids of GAD65 do not contribute to epitopes recognized by Type 1 diabetes-associated GAD antibodies. Low-volume radioimmunoassays using N-terminally truncated 35 S-GAD65 are more specific than those using full-length GAD65 and offer practical alternatives to the GAD antibody ELISA for identifying children at increased risk of Type 1 diabetes.


Assuntos
Autoanticorpos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Glutamato Descarboxilase/imunologia , Fragmentos de Peptídeos/imunologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/diagnóstico , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Família , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Sensibilidade e Especificidade , Adulto Jovem
7.
J Med Genet ; 54(8): 537-543, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28100473

RESUMO

BACKGROUND: Bainbridge-Ropers syndrome (BRPS) is a recently described developmental disorder caused by de novo truncating mutations in the additional sex combs like 3 (ASXL3) gene. To date, there have been fewer than 10 reported patients. OBJECTIVES: Here, we delineate the BRPS phenotype further by describing a series of 12 previously unreported patients identified by the Deciphering Developmental Disorders study. METHODS: Trio-based exome sequencing was performed on all 12 patients included in this study, which found a de novo truncating mutation in ASXL3. Detailed phenotypic information and patient images were collected and summarised as part of this study. RESULTS: By obtaining genotype:phenotype data, we have been able to demonstrate a second mutation cluster region within ASXL3. This report expands the phenotype of older patients with BRPS; common emerging features include severe intellectual disability (11/12), poor/ absent speech (12/12), autistic traits (9/12), distinct face (arched eyebrows, prominent forehead, high-arched palate, hypertelorism and downslanting palpebral fissures), (9/12), hypotonia (11/12) and significant feeding difficulties (9/12) when young. DISCUSSION: Similarities in the patients reported previously in comparison with this cohort included their distinctive craniofacial features, feeding problems, absent/limited speech and intellectual disability. Shared behavioural phenotypes include autistic traits, hand-flapping, rocking, aggressive behaviour and sleep disturbance. CONCLUSIONS: This series expands the phenotypic spectrum of this severe disorder and highlights its surprisingly high frequency. With the advent of advanced genomic screening, we are likely to identify more variants in this gene presenting with a variable phenotype, which this study will explore.


Assuntos
Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/patologia , Mutação com Perda de Função/genética , Fenótipo , Fatores de Transcrição/genética , Adulto , Criança , Pré-Escolar , Deficiências do Desenvolvimento/fisiopatologia , Feminino , Humanos , Masculino , Sequenciamento do Exoma , Adulto Jovem
8.
Clin Genet ; 88(1): 13-24, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25307146

RESUMO

Fanconi anaemia (FA) is an inherited disease with congenital and developmental abnormalities, cross-linker hypersensitivity and extreme cancer predisposition. With better understanding of the genetic and molecular basis of the disease, and improved clinical management, FA has been transformed from a life-limiting paediatric disease to an uncommon chronic condition that needs lifelong multidisciplinary management, and a paradigm condition for the understanding of the gene-environment interaction in the aetiology of congenital anomalies, haematopoiesis and cancer development. Here we review genetic, molecular and clinical aspects of FA, and discuss current controversies and future prospects.


Assuntos
Anemia de Fanconi/genética , Neoplasias/genética , Adulto , Criança , Anormalidades Congênitas/diagnóstico , Gerenciamento Clínico , Anemia de Fanconi/complicações , Anemia de Fanconi/diagnóstico , Anemia de Fanconi/terapia , Feminino , Interação Gene-Ambiente , Humanos , Masculino , Neoplasias/etiologia , Fenótipo
9.
J Viral Hepat ; 21(11): e144-53, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24666386

RESUMO

To examine the associations between maternal hepatitis B (HBV) and hepatitis C (HCV) infection status and selected infant neurological outcomes diagnosed at birth, we conducted a population-based, retrospective cohort study on singleton live births in Florida from 1998 to 2009. Primary exposures included maternal HBV and HCV monoinfection. The neurological outcomes included brachial plexus injury, cephalhematoma, foetal distress, feeding difficulties, intraventricular h aemorrhage and neonatal seizures. Multivariable logistic regression models were used to generate odds ratios (OR) and 95% confidence intervals (CI) that were adjusted for socio-demographic characteristics, risky behaviours, pregnancy complications and pre-existing medical conditions, and timing of delivery. The risk of an adverse neurological outcome was higher in infants born to mothers with hepatitis viral infection (7.2% for HCV, 5.0% for HBV), compared with infants of hepatitis virus-free mothers (4.2%). After adjusting for potential confounders, women with HBV were twice as likely to have infants who suffered from brachial plexus injury (OR = 2.04, 95% CI = 1.15-3.60), while those with HCV had an elevated odds of having an infant with feeding difficulties (OR: 1.32, 95% CI = 1.06-1.64) and a borderline increased likelihood for neonatal seizures (OR = 1.74, 95% CI = 0.98-3.10). Additionally, HCV+ mothers had a 22% increased odds of having an infant with some type of adverse neurological outcome (OR: 1.22, 95% CI = 1.03-1.44). Our findings add to current understanding of the association between maternal HBV/HCV infections and infant neurological outcomes. Further research evaluating the role of maternal HBV and HCV infections (including viraemia, treatment) on pregnancy outcomes is warranted.


Assuntos
Hepatite B/complicações , Hepatite B/epidemiologia , Hepatite C/complicações , Hepatite C/epidemiologia , Doenças do Sistema Nervoso/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Adolescente , Adulto , Estudos de Coortes , Feminino , Florida/epidemiologia , Humanos , Modelos Estatísticos , Gravidez , Prevalência , Estudos Retrospectivos , Adulto Jovem
10.
Nutrients ; 16(10)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38794639

RESUMO

In this interventional pilot study, we investigated the effects of a modified ketogenic diet (KD) on children with autism spectrum disorder (ASD). We previously observed improved behavioral symptoms in this cohort following the KD; this trial was registered with Clinicaltrials.gov (NCT02477904). This report details the alterations observed in the microbiota, inflammation markers, and microRNAs of seven children following a KD for a duration of 4 months. Our analysis included blood and stool samples, collected before and after the KD. After 4 months follow up, we found that the KD led to decreased plasma levels of proinflammatory cytokines (IL-12p70 and IL-1b) and brain-derived neurotrophic factor (BDNF). Additionally, we observed changes in the gut microbiome, increased expression of butyrate kinase in the gut, and altered levels of BDNF-associated miRNAs in the plasma. These cohort findings suggest that the KD may positively influence ASD sociability, as previously observed, by reducing inflammation, reversing gut microbial dysbiosis, and impacting the BDNF pathway related to brain activity.


Assuntos
Transtorno do Espectro Autista , Fator Neurotrófico Derivado do Encéfalo , Citocinas , Dieta Cetogênica , Microbioma Gastrointestinal , MicroRNAs , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Transtorno do Espectro Autista/microbiologia , Transtorno do Espectro Autista/dietoterapia , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/sangue , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Citocinas/sangue , Disbiose , Inflamação , MicroRNAs/sangue , MicroRNAs/metabolismo , Projetos Piloto
11.
Clin Genet ; 83(5): 467-71, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22901312

RESUMO

Kabuki syndrome (KS) is a rare multi-system disorder that can result in a variety of congenital malformations, typical dysmorphism and variable learning disability. It is caused by MLL2 point mutations in the majority of the cases and, rarely by deletions involving KDM6A. Nearly one third of cases remain unsolved. Here, we expand the known genetic basis of KS by presenting five typical patients with the condition, all of whom have novel MLL2 mutation types- two patients with mosaic small deletions, one with a mosaic whole-gene deletion, one with a multi-exon deletion and one with an intragenic multi-exon duplication. We recommend MLL2 dosage studies for all patients with typical KS, where traditional Sanger sequencing fails to identify mutations. The prevalence of such MLL2 mutations in KS may be comparable with deletions involving KDM6A. These findings may be helpful in understanding the mutational mechanism of MLL2 and the disease mechanism of KS.


Assuntos
Anormalidades Múltiplas/genética , Proteínas de Ligação a DNA/genética , Deleção de Genes , Duplicação Gênica , Doenças Hematológicas/genética , Mosaicismo , Mutação , Proteínas de Neoplasias/genética , Doenças Vestibulares/genética , Anormalidades Múltiplas/diagnóstico , Sequência de Bases , Criança , Pré-Escolar , Face/anormalidades , Fácies , Feminino , Genótipo , Doenças Hematológicas/diagnóstico , Humanos , Masculino , Fenótipo , Doenças Vestibulares/diagnóstico
12.
Front Genet ; 14: 1125217, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152987

RESUMO

Introduction: Native Hawaiian and other Pacific Islander (NHPI) populations experience higher rates of immunometabolic diseases compared to other racial-ethnic groups in Hawaii. As annual NHPI mortality rates for suicide and type 2 diabetes mellitus (T2DM) exceed those of the state as a whole, understanding the social and biological mechanisms underlying these disparities are urgently needed to enable preventive strategies. Methods: A community-based approach was used to investigate the immunoepigenetic-gut microbiome axis in an NHPI-enriched cohort of Oahu residents (N = 68). Self-esteem (SE) data was collected using a modified Rosenberg self-esteem (SE) assessment as a proxy measure for mental wellbeing in consideration for cultural competency. T2DM status was evaluated using point-of-care A1c (%) tests. Stool samples were collected for 16s-based metagenomic sequencing analyses. Plasma from blood samples were isolated by density-gradient centrifugation. Peripheral blood mononuclear cells (PBMCs) were collected from the same samples and enriched for monocytes using negative selection techniques. Flow-cytometry was used for immunoprofiling assays. Monocyte DNA was extracted for Illumina EPIC array-based methylation analysis. Results: Compared to individuals with normal SE (NSE), those with low SE (LSE) exhibited significantly higher plasma concentrations (pg/ml) of proinflammatory cytokines IL-8 (p = 0.051) and TNF-α (p = 0.011). Metagenomic analysis revealed that the relative abundance (%) of specific gut bacteria significantly differed between SE groups - some of which directly correlated with SE scores. Gene ontology analysis revealed that 104 significantly differentially methylated loci (DML) between SE groups were preferentially located at genes involved in immunometabolic processes. Horvath clock analyses indicated epigenetic age (Epi-Age) deceleration in individuals with LSE and acceleration in individuals with NSE (p = 0.042), yet was not reproduced by other clocks. Discussion: These data reveal novel differences in the immunoepigenetic-gut microbiome axis with respect to SE, warranting further investigation into its relationship to brain activity and mental health in NHPI. Unexpected results from Epi-Age analyses warrant further investigation into the relationship between biological age and disparate health outcomes among the NHPI population. The modifiable component of epigenetic processes and the gut microbiome makes this axis an attractive target for potential therapeutics, biomarker discovery, and novel prevention strategies.

13.
J Environ Manage ; 113: 117-27, 2012 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-23010623

RESUMO

Countryside Survey is a unique large scale long-term monitoring programme investigating stock and change of habitats, landscape features, vegetation, soil and freshwaters of Great Britain. Repeat field surveys combine policy and scientific objectives to provide evidence on how multiple aspects of the environment are changing over time, a key goal of international science in the face of profound human impacts on ecosystems. Countryside Survey 2007 (CS2007), the fifth survey since 1978, retained consistency with previous surveys, whilst evolving in line with technological and conceptual advances in the collection and integration of data to understand landscape change. This paper outlines approaches taken in the 2007 survey and its subsequent analysis and presents some of the headline results of the survey and their relevance for national and international policy objectives. Key changes between 1998 and 2007 included: a) significant shifts in agricultural land cover from arable to grassland, accompanied by increases in the area of broadleaved woodland, b) decreases in the length of managed hedges associated with agricultural land, as a proportion deteriorated to lines of trees and c) increases in the areas and numbers of wet habitats (standing open water, ponds) and species preferring wetter conditions (1998-2007 and 1978-2007). Despite international policy directed at maintaining and enhancing biodiversity, there were widespread decreases in species richness in all linear and area habitats, except on arable land, consistent with an increase in competitive and late successional species between 1998 and 2007 and 1978 and 2007. Late successional and competitive species: Stinging nettle (Urtica dioica), Hawthorn (Cratageous monogyna) and Bramble (Rubus fruticosus), in the top ten recorded species recorded in 2007, all increased between 1998 and 2007. The most commonly recorded species in CS (1990, 1998 and 2007) was agricultural Ryegrass (Lolium perenne). Increases in both water quality and soil pH were in line with policy aimed at addressing previous deterioration of both. Headwater streams broadly showed continued improvements in biological quality from 1998 to 2007, continuing trends seen since 1990. In soils, there were significant increases in soil pH between 1998 and 2007 consistent with recovery from acidification.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Monitoramento Ambiental/métodos , Solo/análise
14.
Rev Sci Instrum ; 93(10): 103533, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319359

RESUMO

This work presents a novel approach for imaging the visible emissions from plasmas in pulsed power experiments using high-resolution plastic optical fibers. The diagnostic consists of a 2 mm diameter core commercial cable constructed of 13 000 individual acrylic fibers. The fibers are fused together to create a single high-resolution bundle. Different designs were investigated to cover a wide range of resolutions and fields of view (3-700 µm and 0.05-45 mm, respectively). The system was tested on the 1-MA Mykonos accelerator at Sandia National Laboratories and successfully imaged visible emission from a hybrid x-pinch target. Diagnostic development and preliminary results are presented.

15.
Front Psychiatry ; 12: 678090, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093287

RESUMO

Fragile X syndrome (FXS) is the most common cause of inherited intellectual disability. FXS is caused by functional loss of the Fragile X Protein (FXP), also known as Fragile X Mental Retardation Protein (FMRP). In humans and animal models, loss of FXP leads to sensory hypersensitivity, increased susceptibility to seizures and cortical hyperactivity. Several components of the GABAergic system, the major inhibitory system in the brain, are dysregulated in FXS, and thus modulation of GABAergic transmission was suggested and tested as a treatment strategy. However, so far, clinical trials using broad spectrum GABAA or GABAB receptor-specific agonists have not yielded broad improvement of FXS phenotypes in humans. Here, we tested a more selective strategy in Fmr1 knockout (KO) mice using the experimental drug BAER-101, which is a selective GABAA α2/α3 agonist. Our results suggest that BAER-101 reduces hyperexcitability of cortical circuits, partially corrects increased frequency-specific baseline cortical EEG power, reduces susceptibility to audiogenic seizures and improves novel object memory. Other Fmr1 KO-specific phenotypes were not improved by the drug, such as increased hippocampal dendritic spine density, open field activity and marble burying. Overall, this work shows that BAER-101 improves select phenotypes in Fmr1 KO mice and encourages further studies into the efficacy of GABAA-receptor subunit-selective agonists for the treatment of FXS.

16.
J Vet Intern Med ; 24(2): 372-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20102497

RESUMO

BACKGROUND: Vector-transmitted microorganisms in the genera Ehrlichia, Anaplasma, Rickettsia, Bartonella, and Borrelia are commonly suspected in dogs with meningoencephalomyelitis (MEM), but the prevalence of these pathogens in brain tissue and cerebrospinal fluid (CSF) of dogs with MEM is unknown. HYPOTHESIS/OBJECTIVES: To determine if DNA from these genera is present in brain tissue and CSF of dogs with MEM, including those with meningoencephalitis of unknown etiology (MUE) and histopathologically confirmed cases of granulomatous (GME) and necrotizing meningoencephalomyelitis (NME). ANIMALS: Hundred and nine dogs examined for neurological signs at 3 university referral hospitals. METHODS: Brain tissue and CSF were collected prospectively from dogs with neurological disease and evaluated by broadly reactive polymerase chain reaction (PCR) for Ehrlichia, Anaplasma, Spotted Fever Group Rickettsia, Bartonella, and Borrelia species. Medical records were evaluated retrospectively to identify MEM and control cases. RESULTS: Seventy-five cases of MUE, GME, or NME, including brain tissue from 31 and CSF from 44 cases, were evaluated. Brain tissue from 4 cases and inflammatory CSF from 30 cases with infectious, neoplastic, compressive, vascular, or malformative disease were evaluated as controls. Pathogen nucleic acids were detected in 1 of 109 cases evaluated. Specifically, Bartonella vinsonii subsp. berkhoffii DNA was amplified from 1/6 dogs with histopathologically confirmed GME. CONCLUSION AND CLINICAL IMPORTANCE: The results of this investigation suggest that microorganisms in the genera Ehrlichia, Anaplasma, Rickettsia, and Borrelia are unlikely to be directly associated with canine MEM in the geographic regions evaluated. The role of Bartonella in the pathogenesis of GME warrants further investigation.


Assuntos
Encéfalo/microbiologia , Doenças do Cão/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/veterinária , Meningoencefalite/veterinária , Reação em Cadeia da Polimerase/veterinária , Animais , DNA Bacteriano/classificação , DNA Bacteriano/isolamento & purificação , Doenças do Cão/líquido cefalorraquidiano , Cães , Feminino , Infecções por Bactérias Gram-Negativas/líquido cefalorraquidiano , Infecções por Bactérias Gram-Negativas/microbiologia , Masculino , Meningoencefalite/microbiologia
17.
Hum Mutat ; 30(9): E845-54, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19533689

RESUMO

Cohen syndrome is an autosomal recessive disorder that is characterized by mental retardation, facial dysmorphism, microcephaly, retinal dystrophy, truncal obesity, joint laxity and intermittent neutropenia. Mutations in the VPS13B (COH1) gene underlie Cohen syndrome. In approximately 70% of the patients mutations in the gene are identified on both alleles, while in about 30% only a mutation in a single allele or no mutant allele is detected. The VPS13B locus was recently added to the growing list of benign copy number variants. We hypothesized that patients with unexplained Cohen syndrome would harbour deletions affecting the VPS13B locus. We screened 35 patients from 26 families with targeted array CGH and identified 7 copy number alterations: 2 homozygous and 5 heterozygous deletions. Our results show that deletions are an important cause of Cohen syndrome and screening for copy number alterations of VPS13B should be an integral part of the diagnostic work-up of these patients. These findings have important consequences for the diagnosis of patients with genetic disorders in general since, as we highlight, rare benign copy number variants can underly autosomal recessive disorders and lead to disease in homozygous state or in compound heterozygosity with another mutation.


Assuntos
Anormalidades Múltiplas/genética , Deleção de Sequência , Proteínas de Transporte Vesicular/genética , Anormalidades Múltiplas/patologia , Adulto , Sequência de Bases , Criança , Análise Mutacional de DNA , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/patologia , Masculino , Microcefalia/genética , Microcefalia/patologia , Neutropenia/genética , Neutropenia/patologia , Fenótipo , Síndrome , Proteínas de Transporte Vesicular/metabolismo
18.
J Econ Entomol ; 102(4): 1523-35, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19736765

RESUMO

Decision support systems have been developed for risk analysis and management of root-feeding white grubs (Coleoptera: Scarabaeidae: Melolonthinae) in Queensland, Australia, sugarcane (Saccharum spp.), based partly on manual inspection of soil samples. Acoustic technology was considered as a potential alternative to this laborious procedure. Field surveys were conducted to detect the major pests Dermolepida albohirtum (Waterhouse) near Mackay, and Antitrogus parvulus Britton near Bundaberg. Computer analyses were developed to identify distinctive scrapes and other sounds produced by D. albohirtum and Antitrogus species and to distinguish them from sounds of nondamaging white grubs (Rutelinae, Dynastinae), as well as from extraneous, wind-induced tapping signals. Procedures were considered for incorporating acoustic methods into surveys and sequential sampling plans. Digging up and inspecting sugarcane root systems requires 10-12 min per sample, but acoustic assessments can be obtained in 3-5 min, so labor and time could be reduced by beginning the surveys with acoustic sampling. In a typical survey conducted in a field with low population densities, sampling might terminate quickly after five negative acoustic samples, establishing a desired precision level of 0.25 but avoiding the effort of excavating and inspecting empty samples. With a high population density, sampling might terminate also if signals were detected in five samples, in which case it would be beneficial to excavate the samples and count the white grubs. In intermediate populations, it might be necessary to collect up to 20 samples to achieve desired precision, and acoustic methods could help determine which samples would be best to excavate.


Assuntos
Acústica , Besouros/fisiologia , Controle de Insetos/métodos , Saccharum , Animais , Besouros/crescimento & desenvolvimento , Comportamento Alimentar , Larva/fisiologia , Densidade Demográfica , Queensland , Medição de Risco
19.
Vet Comp Orthop Traumatol ; 22(5): 427-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19750291

RESUMO

A variety of clinical disorders caused by the foreign body reaction to migrating plant material have been reported in the dog. In this report, we describe a novel presentation in an adult dog in which this condition produced signs of progressive thoracic limb lameness and cervical spinal pain, mimicking a tumour of the brachial plexus.


Assuntos
Neuropatias do Plexo Braquial/veterinária , Doenças do Cão/patologia , Corpos Estranhos/veterinária , Neoplasias de Bainha Neural/veterinária , Animais , Neuropatias do Plexo Braquial/etiologia , Neuropatias do Plexo Braquial/patologia , Doenças do Cão/diagnóstico , Cães , Corpos Estranhos/complicações , Corpos Estranhos/patologia , Masculino , Neoplasias de Bainha Neural/patologia , Plantas
20.
J Mol Graph Model ; 86: 235-246, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30390544

RESUMO

G protein-coupled receptors (GPCR) are integral membrane proteins of considerable interest as targets for drug development. GPCR ligand interaction studies often have a starting point with either crystal structures or comparative models. The majority of GPCR do not have experimentally-characterized 3-dimensional structures, so comparative modeling, also called homology modeling, is a good structure-based starting point. Comparative modeling is a widely used method for generating models of proteins with unknown structures by analogy to crystallized proteins that are expected to exhibit structural conservation. Traditionally, comparative modeling template selection is based on global sequence identity and shared function. However high sequence identity localized to the ligand binding pocket may produce better models to examine protein-ligand interactions. This in silico benchmark study examined the performance of a global versus local similarity measure applied to comparative modeling template selection for 6 previously crystallized, class A GCPR (CXCR4, FFAR1, NOP, P2Y12, OPRK, and M1) with the long-term goal of optimizing GPCR ligand identification efforts. Comparative models were generated from templates selected using both global and local similarity measures. Similarity to reference crystal structures was reflected in RMSD values between atom positions throughout the structure or localized to the ligand binding pocket. Overall, models deviated from the reference crystal structure to a similar degree regardless of whether the template was selected using a global or local similarity measure. Ligand docking simulations were performed to assess relative performance in predicting protein-ligand complex structures and interaction networks. Calculated RMSD values between ligand poses from docking simulations and crystal structures indicate that models based on locally selected templates give docked poses that better mimic crystallographic ligand positions than those based on globally-selected templates in five of the six benchmark cases. However, protein model refinement strategies in advance of ligand docking applications are clearly essential as the average RMSD between crystallographic poses and poses docked into local template models was 9.7 Šand typically less than half of the ligand interaction sites are shared between the docked and crystallographic poses. These data support the utilization of local similarity measures to guide template selection in protocols using comparative models to investigate ligand-receptor interactions.


Assuntos
Simulação de Dinâmica Molecular , Conformação Proteica , Receptores Acoplados a Proteínas G/química , Homologia Estrutural de Proteína , Ligantes , Simulação de Acoplamento Molecular , Estrutura Molecular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA