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This paper presents an approach to enable interoperability of the research data management system XNAT by the implementation of the HL7 standards framework Fast Healthcare Interoperability Resources (FHIR). The FHIR implementation is realized as an XNAT plugin (Source code: https://github.com/somnonetz/xnat-fhir-plugin ), that allows easy adoption in arbitrary XNAT instances. The approach is demonstrated on patient data exchange between a FHIR reference implementation and XNAT.
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Nível Sete de Saúde/organização & administração , Sistemas Computadorizados de Registros Médicos/organização & administração , Neuroimagem/métodos , Gerenciamento de Dados , Registros Eletrônicos de Saúde , Nível Sete de Saúde/normas , Humanos , Sistemas Computadorizados de Registros Médicos/normas , Integração de SistemasRESUMO
BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is the fourth most common cause of cancer related death. It is lethal in nearly all patients, due to an almost complete chemoresistance. Most if not all drugs that pass preclinical tests successfully, fail miserably in the patient. This raises the question whether traditional 2D cell culture is the correct tool for drug screening. The objective of this study is to develop a simple, high-throughput 3D model of human PDAC cell lines, and to explore mechanisms underlying the transition from 2D to 3D that might be responsible for chemoresistance. METHODS: Several established human PDAC and a KPC mouse cell lines were tested, whereby Panc-1 was studied in more detail. 3D spheroid formation was facilitated with methylcellulose. Spheroids were studied morphologically, electron microscopically and by qRT-PCR for selected matrix genes, related factors and miRNA. Metabolic studies were performed, and a panel of novel drugs was tested against gemcitabine. RESULTS: Comparing 3D to 2D cell culture, matrix proteins were significantly increased as were lumican, SNED1, DARP32, and miR-146a. Cell metabolism in 3D was shifted towards glycolysis. All drugs tested were less effective in 3D, except for allicin, MT100 and AX, which demonstrated effect. CONCLUSIONS: We developed a high-throughput 3D cell culture drug screening system for pancreatic cancer, which displays a strongly increased chemoresistance. Features associated to the 3D cell model are increased expression of matrix proteins and miRNA as well as stromal markers such as PPP1R1B and SNED1. This is supporting the concept of cell adhesion mediated drug resistance.
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Antineoplásicos/farmacologia , Carcinoma Ductal Pancreático/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas da Matriz Extracelular/genética , Neoplasias Pancreáticas/genética , Fenótipo , Esferoides Celulares/efeitos dos fármacos , Animais , Antineoplásicos/toxicidade , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Ensaios de Seleção de Medicamentos Antitumorais , Metabolismo Energético , Proteínas da Matriz Extracelular/metabolismo , Humanos , Ácido Láctico/metabolismo , Camundongos , Neoplasias Pancreáticas/metabolismo , Células Tumorais CultivadasRESUMO
Objective: Endotracheal intubation is a common procedure in the medical intensive care unit (MICU), but it carries risk of complications including, but not limited to, subglottic stenosis (SGS) and tracheal stenosis (TS). Current literature suggests identifiable risk factors for the development of airway complications. This study is a comprehensive evaluation of potential risk factors in patients who developed SGS and TS following endotracheal intubation in our MICU. Methods: Patients intubated in our MICU were identified from 2013 to 2019. Diagnoses of SGS or TS within 1 year of MICU admission were identified. Data extracted included age, sex, body measurements, comorbidities, bronchoscopies, endotracheal tube size, tracheostomy, social history, and medications. Patients with prior diagnosis of airway complication, tracheostomy, or head and neck cancer were excluded. Univariate and multivariate logistic regressions were performed. Results: A total of 136 patients with TS or SGS were identified out of a sample of 6603 patients intubated in the MICU. Cases were matched to controls who did not develop airway stenosis based on identical Charlson Comorbidity Index scores. Eighty six controls were identified with a complete record of endotracheal/tracheostomy tube size, airway procedures, sociodemographic data, and medical diagnosis. Regression analysis showed that SGS or TS were associated with tracheostomy, bronchoscopy, chronic obstructive pulmonary disease, current tobacco use, gastroesophageal reflux disease, systemic lupus erythematosus, pneumonia, bronchitis, and numerous medication classes. Conclusion: Various conditions, procedures, and medications are associated with an increased risk of developing SGS or TS. Level of evidence: 4.
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For more than ten years, re3data, a global registry of research data repositories (RDRs), has been helping scientists, funding agencies, libraries, and data centers with finding, identifying, and referencing RDRs. As the world's largest directory of RDRs, re3data currently describes over 3,000 RDRs on the basis of a comprehensive metadata schema. The service allows searching for RDRs of any type and from all disciplines, and users can filter results based on a wide range of characteristics. The re3data RDR descriptions are available as Open Data accessible through an API and are utilized by numerous Open Science services. re3data is engaged in various initiatives and projects concerning data management and is mentioned in the policies of many scientific institutions, funding organizations, and publishers. This article reflects on the ten-year experience of running re3data and discusses ten key issues related to the management of an Open Science service that caters to RDRs worldwide.
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Objectives/hypothesis: To identify sociodemographic factors associated with the development of airway stenosis (AS) among intubated medical intensive care unit (MICU) patients. Study design: Retrospective cohort study. Methods: A retrospective review of adult MICU intubated patients from 2013 to 2019 at a single academic institution was performed. Univariate and multivariate analysis with logistic regression examined associations between the development of AS and subsite abnormalities such as posterior glottic stenosis (PGS), subglottic stenosis (SGS), tracheal stenosis (TS), vocal fold immobility (VFI), and posterior glottic granuloma (PGG) with age, body mass index (BMI), height, weight, race, ethnicity, sex, rurality, Appalachian status, length of admission, distance to hospital, and median household income. Results: Of an overall sample of 6603 MICU patients, 449 intubated patients were included in the study, and 204 patients were found to have AS. AS was statistically associated with decreased driving distance to the hospital and increases in BMI. PGS was statistically associated with increases in age. TS was statistically associated with increases in admission duration and not having residence status in Appalachia. VFI was statistically associated with decreases in driving distance to the hospital and not having residence status in Appalachia. Additionally, black patients had a higher odds of developing VFI compared to Caucasian patients. Conclusion: AS is associated with sociodemographic factors such as age, BMI, shorter distance to hospital, admission duration, and no Appalachian status. These data demonstrate the need to further investigate the impact of social determinants of health on airway pathology and outcomes. Level of evidence: 4.
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OBJECTIVE: Assess Child and Adult Care Food Program (CACFP) program compliance with meal component requirements for children aged 3-5 years by program type, and describe foods and beverages most commonly served. DESIGN: Cross-sectional analysis of 1-week menu surveys during winter/spring 2017. SETTING: US CACFP-participating child care programs. PARTICIPANTS: Nationally representative multistage cluster sample of 664 programs: 222 child care centers, 247 Head Start programs, 195 family child care homes. MAIN OUTCOME MEASURE(S): Percentage of meals including required components; frequently served foods and beverages. ANALYSIS: Mean percentages; 2-tailed t tests; alphaâ¯=â¯0.05 significance level. RESULTS: Most breakfasts (97%), lunches (88%), and afternoon snacks (97%) included all required CACFP meal components. Most breakfasts included fruits (96%), but not vegetables; 16% included a meat/meat alternate. Most lunches (81%) included both fruits and vegetables. Afternoon snacks were mostly grains/breads (80%) and fruits (57%). Most frequently served foods included 1% unflavored milk and fresh fruits such as apples and bananas. Most menus limited juice, offered low-sugar cereal, and did not include flavored milk; very few menus included noncreditable foods with added sugar. CONCLUSIONS AND IMPLICATIONS: Most CACFP meals provided required components, but there is room for improvement, particularly for increasing vegetables served and limiting foods high in added sugar and fat.
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Cuidado da Criança , Serviços de Alimentação , Adulto , Criança , Creches , Estudos Transversais , Comportamento Alimentar , Humanos , Refeições , Política Nutricional , Açúcares , VerdurasRESUMO
BACKGROUND AND OBJECTIVES: Physical activity provides health and developmental benefits to young children. The Study of Nutrition and Activity in Child Care Settings describes physical activity opportunities and sedentary occasions for children aged 1 to 5 years at programs participating in the US Department of Agriculture Child and Adult Care Food Program. METHODS: The Study of Nutrition and Activity in Child Care Settings obtained a nationally representative sample of classrooms within Child and Adult Care Food Program-participating Head Start and child care centers via multistage cluster sampling. For 1 observation day, an observer in each classroom tallied designated outdoor and indoor playspaces; minutes children spent in playspaces; barriers and facilitators to physical activity; and classroom time when most children were physically active (eg, walking, dancing), sedentary (seated, lying down), or neither. Weighted descriptive tabulations by program type compared outdoor physical activity opportunity counts and total physical activity opportunity durations to national guidelines. Multivariate regression analysis investigated association of barriers with physical activity opportunity duration. RESULTS: The sample included 227 classrooms, 96 in child care centers and 131 in Head Start programs. All had sedentary occasions outside meals, snacks, and naps; virtually all offered opportunities for physical activity. Seventy-four percent of programs met national guidance on sufficient number of outdoor opportunities, weather permitting. Just 50% met guidance of ≥60 to 90 minutes of physical activity, whereas only 43% met both sets of guidance. Weather and staff not joining in outdoor play were associated with 74 and 31 fewer minutes devoted to physical activity, respectively. CONCLUSIONS: Findings suggest ample room for improvement in provision of physical activity opportunities during child care.
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Cuidado da Criança , Creches , Adulto , Criança , Saúde da Criança , Pré-Escolar , Intervenção Educacional Precoce , Exercício Físico , HumanosRESUMO
OBJECTIVES/HYPOTHESIS: To better assess rates of postoperative complications and mortality following esophageal dilation, and to identify factors associated with adverse outcomes. STUDY DESIGN: Observational, retrospective cohort study. METHODS: We queried a national database of insurance claims for Current Procedural Terminology (CPT) codes representing esophageal dilation performed between 2011 and 2017. Patients aged 18 to 100 who were continuously enrolled with their insurance provider were included. Demographic information, additional CPT codes, concomitant diagnoses, and anticoagulant medication data were collected for all patients included. Postoperative mortality was assessed and International Classification of Diseases (ICD)9/10 codes for complications, including esophageal perforation, hemorrhage, mediastinitis, and sepsis were flagged. RESULTS: We identified 202,965 encounters for esophageal dilation. Of these procedures, 193 were performed on a patient who underwent percutaneous endoscopic gastrostomy (PEG) during the study period and was analyzed separately. Another 244 dilations were excluded due to repeat entries. Of the remaining 202,528 procedures remaining, 42,310 were repeat dilations in the same patient. Data analysis was confined to each patient's initial dilation. 160,218 initial dilations remained. Of these, 62,107 were performed on male patients and 98,111 were performed on female patients. The average age was 57.7 years. There were 12 mortalities within 30 days postoperatively, representing 0.0075% of all dilations. Esophageal perforation and esophageal hemorrhage were the most common reported complications, with 139 and 110 occurrences, respectively. The overall per-dilation complication rate was 0.215%. CONCLUSIONS: Evidence from a national insurance claim database suggests that esophageal dilation is a safe procedure with a low rate of serious complications and a 30-day all-cause mortality rate of less than 1 per 10,000 dilations. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:2436-2440, 2021.
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Transtornos de Deglutição/cirurgia , Dilatação/efeitos adversos , Esôfago/cirurgia , Complicações Pós-Operatórias/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Estudos de Casos e Controles , Current Procedural Terminology , Bases de Dados Factuais , Dilatação/estatística & dados numéricos , Doenças do Esôfago/patologia , Perfuração Esofágica/epidemiologia , Esôfago/patologia , Feminino , Gastrostomia/estatística & dados numéricos , Gastrostomia/tendências , Hemorragia/epidemiologia , Humanos , Classificação Internacional de Doenças/normas , Masculino , Mediastinite/epidemiologia , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Sepse/epidemiologiaRESUMO
BACKGROUND: Assessment of lymphatic status via sentinel lymph node (SLN) biopsy is an integral and crucial part of melanoma surgical oncology. The most common technique for sentinel node mapping is preoperative planar scintigraphy of an injected gamma-emitting lymphatic tracer followed by intraoperative node localization using a non-imaging gamma probe with auditory feedback. In recent years, intraoperative visualization of SLNs in 3D has become possible by coupling the probe to an external system capable of tracking its location and orientation as it is read out, thereby enabling computation of the 3D distribution of the tracer (freehand SPECT). In this project, the non-imaging probe of the fhSPECT system was replaced by a unique handheld gamma camera containing an array of sodium iodide crystals optically coupled to an array of silicon photomultipliers (SiPMs). A feasibility study was performed in which preoperative SLN mapping was performed using camera fhSPECT and the number of detected nodes was compared to that visualized by lymphoscintigraphy, probe fhSPECT, and to the number ultimately excised under non-imaging probe guidance. RESULTS: Among five subjects, SLNs were detected in nine lymphatic basins, with one to five SLNs detected per basin. A basin-by-basin comparison showed that the number of SLNs detected using camera fhSPECT exceeded that using lymphoscintigraphy and probe fhSPECT in seven of nine basins and five of five basins, respectively. (Probe fhSPECT scans were not performed for four basins.) It exceeded the number excised under non-imaging probe guidance for seven of nine basins and equaled the number excised for the other two basins. CONCLUSIONS: Freehand SPECT using a prototype SiPM-based gamma camera demonstrates high sensitivity for detection of SLNs in a preoperative setting. Camera fhSPECT is a potential means for efficiently obtaining real-time 3D activity distribution maps in applications such as image-guided percutaneous biopsy, and surgical SLN biopsy or radioguided tumor excision.
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Nontraumatic abdominal apoplexy, which is the occurrence of hemorrhage into the peritoneal cavity, is uncommon in the pediatric literature. Adult case reports of nontraumatic abdominal apoplexy include visceral artery aneurysms from the aorta, splenic, celiac, hepatic, gastric, and gastroepiploic arteries as well as gynecologic pathology. We identified 2 case reports of spontaneous abdominal apoplexy due to injury of the short gastric arteries in adult patients with histories of vomiting after alcohol consumption. This is the first reported case of nontraumatic abdominal apoplexy due to injury to the short gastric arteries in a pediatric patient.
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Abdome Agudo/etiologia , Hemoperitônio/diagnóstico , Estômago/irrigação sanguínea , Adolescente , Hemoperitônio/complicações , Hemoperitônio/cirurgia , Humanos , Masculino , Ruptura EspontâneaRESUMO
Spinal cord injury (SCI) causes male infertility, with low sperm motility the major long-term cause. It has been suggested in previous studies that some seminal components may be responsible for the pathological asthenozoospermia. It is hypothesized that platelet-activating factor (PAF) acetylhydrolase (PAFah), which originates in the epididymis and other accessory sexual glands, may be a causative factor. This enzyme catalyzes PAF to acetate and biologically inactive lyso-PAF. PAF is well recognized to be an important phospholipid mediator that stimulates sperm motility and enhances sperm capacitation and fertilization. The present study was designed to analyze differences in PAFah activity in semen of men with SCI and age-matched healthy men. PAFah assay reagent kits were used to measure enzymatic activity by monitoring the production rates of 4-nitrophenol on a spectrophotometer during a given interval. The results showed that subjects with SCI had a higher concentration of PAFah than men in the control group (P < .001). A statistically significant negative correlation was found between enzymatic activity and sperm motility (r(2) = 0.8449; P < .001). Further studies will determine whether seminal vesicle dysfunction in men with SCI leads to abnormal PAFah activity, resulting in low sperm motility.
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1-Alquil-2-acetilglicerofosfocolina Esterase/metabolismo , Sêmen/enzimologia , Traumatismos da Medula Espinal/enzimologia , Adulto , Humanos , Infertilidade Masculina/etiologia , Masculino , Motilidade dos Espermatozoides/fisiologia , Traumatismos da Medula Espinal/complicaçõesRESUMO
Body mass index (BMI) has been demonstrated to affect female fertility; however, little information is available on the impact of BMI on male fertility or semen parameters. Therefore, the study objective was to determine the relationship between BMI and semen parameters, including sperm chromatin integrity. We analyzed data on semen samples from 520 men who were grouped based upon calculated BMI values (normal, 20-24 kg/m(2); overweight, 25-30 kg/m(2); obese, >30 kg/m(2)). The data collected included patient height and weight, semen volume, sperm concentration, percent sperm motility, percent sperm morphology (normal forms), and sperm chromatin integrity (DNA fragmentation index [DFI]). Data were analyzed by regression analysis and analysis of variance (ANOVA) with Tukey's test for multiple pairwise comparisons. The overall BMI mean (+/-SEM) was 27.5 (+/-0.49) kg/m(2). Linear regression revealed a significant (P < .05) and negative relationship between BMI and the total number of normal-motile sperm cells. ANOVA revealed a significant difference (P < .05) in the total number of normal-motile sperm cells among the different BMI groups. The number of normal-motile sperm cells per BMI group was as follows: normal, 18.6 x 10(6); overweight, 3.6 x 10(6); and obese, (0.7) x 10(6). All multiple pairwise comparisons were found to be significantly (P < .05) different. The overall DFI mean (+/-SEM) was 24.7 (+/-2.57). Linear regression revealed a significant (P < .05) and positive relation between BMI and DFI. Men presenting with a BMI greater than 25 kg/m(2) have fewer chromatin-intact normal-motile sperm cells per ejaculate. Therefore, to ensure maximum fertility potential, patients may be advised to reduce body weight.
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Índice de Massa Corporal , Contagem de Espermatozoides , Espermatozoides/fisiologia , Adulto , Humanos , Infertilidade Masculina/etiologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Motilidade dos Espermatozoides/fisiologiaRESUMO
AIMS: The primary aim of the study was to determine if the gonococcal porA pseudogene is a stable sequence target for the detection of Neisseria gonorrhoeae by PCR. METHODS: A total of 240 gonococcal strains from various geographic locations were tested by porA pseudogene PCR. In addition, porA pseudogene PCR positivity rates were compared with established gonococcal assays in three Australian states. RESULTS: All N. gonorrhoeae isolates provided positive results in the porA pseudogene PCR. Positivity rates compared favourably with established gonococcal assays, with increased N. gonorrhoeae detection in the Northern Territory and Western Australia. CONCLUSIONS: The results of this multicentre study provide further evidence that the porA pseudogene is highly conserved across a diverse range N. gonorrhoeae strains and is a suitable PCR target for routine detection of N. gonorrhoeae.
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Técnicas de Diagnóstico Urológico , Gonorreia/diagnóstico , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/isolamento & purificação , Porinas/genética , Reações Falso-Positivas , Gonorreia/microbiologia , Humanos , Neisseria gonorrhoeae/classificação , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Especificidade da EspécieRESUMO
Human sample data is stored in biobanks with software managing digital derived sample data. When these stand-alone components are connected and a search infrastructure is employed users become able to collect required research data from different data sources. Data protection, patient rights, data heterogeneity and access control are major challenges for such an infrastructure. This dissertation will investigate concepts for a multi-level security architecture to comply with these requirements.
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Segurança Computacional , Confidencialidade , Armazenamento e Recuperação da Informação , Humanos , SoftwareRESUMO
There is a slow but continuous decline in testosterone (T) levels with age, with a substantial percentage of males exhibiting T levels in the hypogonadal range. This age-dependent decline in circulating androgens is associated, in large part, with reduced sexual functioning and libido. The effectiveness of TestimR 1% (Auxilium Pharmaceuticals, Inc., Norristown, Pennsylvania) topical T gel was evaluated in older hypogonadal males who failed to experience satisfactory symptom relief after treatment with AndroGelR 1% (Solvay Pharmaceuticals, Inc., Marietta, Georgia). In this open-label study, consecutive subjects were assigned randomly to experimental treatment with Testim 1% (5 g) or to maintenance therapy (control group) with AndroGel 1% (5 g). Seventy-six experimental subjects and 75 control subjects were followed for 4 weeks to evaluate improvements in sexual functioning and satisfaction. Changes from baseline in the 5 domains of the Brief Male Sexual Function Inventory were compared between groups. The mean percentage improvement favored the experimental treatment in sexual drive (23% vs 16%, P < 0.3), erectile function (32% vs 8%, P < 0.03), ejaculatory function (11% vs 9%, P < 0.4), problem assessment (47% vs 12%, P < 0.01), and sexual satisfaction (62% vs 23%, P < 0.02). A greater percentage of subjects also reported satisfaction with the experimental treatment (55% vs 33%, P < 0.02), and these subjects were less likely to require upward dose titration at the final follow-up visit (53% vs 72%, P < 0.03). Consideration of Testim 1% gel in patients who have an inadequate response to prior T therapy is encouraged, although it is difficult to estimate the contribution of nonspecific study effects (eg, placebo) in this trial.
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Androgênios/administração & dosagem , Hipogonadismo/tratamento farmacológico , Satisfação do Paciente , Comportamento Sexual/fisiologia , Testosterona/administração & dosagem , Seguimentos , Humanos , Hipogonadismo/sangue , Hipogonadismo/fisiopatologia , Masculino , Pessoa de Meia-Idade , Retratamento , Resultado do TratamentoRESUMO
BACKGROUND: In recent years polymerase chain reaction (PCR) has proven to be a highly sensitive and specific method for the diagnosis of herpes simplex virus (HSV) infections. The advent of real-time HSV PCR protocols now enables rapid result turnaround times with minimal hands-on time. OBJECTIVES: In this study, we developed a real-time duplex PCR assay (HSVgD-dPCR) comprising of HSV and internal control PCR reactions. STUDY DESIGN: Using the LightCycler, the HSVgD-dPCR targeted the HSV glycoprotein D gene and HSV typing was performed by melting curve analysis. The internal control PCR reaction targeted sequences of the DNA of the human endogenous retrovirus (ERV-3). In total, 300 swab specimens, from patients with suspected HSV infection, were tested by the HSVgD-dPCR assay. The results were then compared to the results obtained by another HSV LightCycler assay, which utilized published primer and probe sequences targeting the HSV DNA polymerase gene (Dpol-HSV-LCPCR). RESULTS: Overall, 91 (30.3%) specimens were positive and 204 (68.0%) specimens were negative for HSV by both LightCycler assays. In addition, four (1.3%) specimens were positive by Dpol-HSV-LCPCR and negative by HSVgD-dPCR, whereas one (0.3%) specimen was positive by HSVgD-dPCR and negative by Dpol-HSV-LCPCR. The presence of HSV in these five specimens was confirmed by conventional PCR. Melting curve analysis by the HSVgD-dPCR assay enabled all HSV positive specimens to be typed, whereas sequence variation prevented three HSV positive specimens from being typed by the Dpol-HSV-LCPCR. Using the ERV-3 PCR, 5% specimens were found to contain inhibitory substances. CONCLUSIONS: By developing the HSVgD-dPCR we have enhanced the diagnostic utility of real-time detection of HSV by incorporating an internal control reaction and by accurately typing a greater proportion of HSV positive specimens.
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Herpes Simples/diagnóstico , Herpesvirus Humano 1/classificação , Herpesvirus Humano 1/isolamento & purificação , Herpesvirus Humano 2/classificação , Herpesvirus Humano 2/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , DNA Polimerase Dirigida por DNA/genética , Exodesoxirribonucleases/genética , Feminino , Herpes Genital/diagnóstico , Herpes Genital/virologia , Herpes Simples/virologia , Herpesvirus Humano 1/genética , Herpesvirus Humano 2/genética , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Sensibilidade e Especificidade , Proteínas do Envelope Viral/genética , Proteínas Virais/genéticaRESUMO
A facile, high-yield synthesis of Cl(3)VNSiMe(3) (1) is reported. 1 and the metal nitride halides Cl(3)MoN and Cl(3)WN react with [{(Me(2)N)(2)PNH(2)}(2)N](+)Cl(-) to form the six-membered metallacyclophosphazenes [(Me(2)N)(2)PN](2)VCl(2) (2), [(Me(2)N)(2)PN](2)MoCl(3).MeCN (3), and [(Me(2)N)(2)PN](2)WCl(3).MeCN (4), respectively. The X-ray structure determinations of 2 and 3 show the compounds to have planar six-membered rings of distorted geometry.
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Monitored natural attenuation (MNA) has recently emerged as a viable groundwater remediation technology in the United States. Area 6 at Dover Air Force Base (Dover, DE) was chosen as a test site to examine the potential for MNA of tetrachloroethene (PCE) and trichloroethene (TCE) in groundwater and aquifer sediments. A "lines of evidence" approach was used to document the occurrence of natural attenuation. Chlorinated hydrocarbon and biogeochemical data were used to develop a site-specific conceptual model where both anaerobic and aerobic biological processes are responsible for the destruction of PCE, TCE, and daughter metabolites. An examination of groundwater biogeochemical data showed a region of depleted dissolved oxygen with elevated dissolved methane and hydrogen concentrations. Reductive dechlorination likely dominated in the anaerobic portion of the aquifer where PCE and TCE levels were observed to decrease with a simultaneous increase in cis-1,2-dichloroethene (cis-DCE), vinyl chloride (VC), ethene, and dissolved chloride. Near the anaerobic/ aerobic interface, concentrations of cis-DCE and VC decreased to below detection limits, presumably due to aerobic biotransformation processes. Therefore, the contaminant and daughter product plumes present at the site appear to have been naturally atteuated by a combination of active anaerobic and aerobic biotransformation processes.
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Compostos Clorados/química , Poluentes do Solo/análise , Solventes/química , Poluentes da Água/análise , Bactérias Aeróbias , Bactérias Anaeróbias , Compostos Clorados/análise , Compostos Clorados/metabolismo , Delaware , Monitoramento Ambiental , Fenômenos Geológicos , Geologia , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/química , Hidrocarbonetos Clorados/metabolismo , Poluentes do Solo/metabolismo , Solventes/análise , Solventes/metabolismo , Poluentes da Água/metabolismoRESUMO
The effects of thyroxine and its related compounds on the benzodiazepine-insensitive γ-aminobutyric acid type A (GABA(A)) receptors were studied. Thyroxine at micromolar concentrations potentiated the (3)H-Ro15-4513 binding to rat brain membranes in-vitro in the thalamus, striatum, cortex and hippocampus, but not in cerebellum. In the thalamus, the rank order of potency was the following: 3,3',5,5'-tetraiodothyroacetic acid (TETRAC)>L-thyroxine>3,5-diiodo-l-thyronine (3,5-T2). TETRAC induced a slight potentiation of flumazenil binding to diazepam-sensitive GABA(A) receptors in the thalamus and striatum while no effect was found in cortex and hippocampus. Consequently, we examined whether these compounds could exert their modulatory effect on the currents mediated by benzodiazepine-insensitive GABA(A) receptors. The diazepam-insensitive GABA(A) receptor-mediated currents were recorded from acutely isolated rat ventrobasal thalamic neurons by applying low concentrations of 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP). TETRAC and thyroxine at low µM concentrations potentiated the THIP-evoked currents, although 3,5-T2 had no effect on the THIP-induced currents. Ethanol had no effect on the enhancing effects of TETRAC. TETRAC itself evoked GABA(A) receptor-mediated currents at high concentrations beyond 30 µM. Although the effects of TETRAC and thyroxine were observed at non-physiological concentrations of hormones, the present results might lead to new lead structures with specificity to diazepam-insensitive GABA(A) receptor subtypes.