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1.
Earth Space Sci ; 8(7): e2020EA001634, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34435081

RESUMO

The ACT-America project is a NASA Earth Venture Suborbital-2 mission designed to study the transport and fluxes of greenhouse gases. The open and freely available ACT-America data sets provide airborne in situ measurements of atmospheric carbon dioxide, methane, trace gases, aerosols, clouds, and meteorological properties, airborne remote sensing measurements of aerosol backscatter, atmospheric boundary layer height and columnar content of atmospheric carbon dioxide, tower-based measurements, and modeled atmospheric mole fractions and regional carbon fluxes of greenhouse gases over the Central and Eastern United States. We conducted 121 research flights during five campaigns in four seasons during 2016-2019 over three regions of the US (Mid-Atlantic, Midwest and South) using two NASA research aircraft (B-200 and C-130). We performed three flight patterns (fair weather, frontal crossings, and OCO-2 underflights) and collected more than 1,140 h of airborne measurements via level-leg flights in the atmospheric boundary layer, lower, and upper free troposphere and vertical profiles spanning these altitudes. We also merged various airborne in situ measurements onto a common standard sampling interval, which brings coherence to the data, creates geolocated data products, and makes it much easier for the users to perform holistic analysis of the ACT-America data products. Here, we report on detailed information of data sets collected, the workflow for data sets including storage and processing of the quality controlled and quality assured harmonized observations, and their archival and formatting for users. Finally, we provide some important information on the dissemination of data products including metadata and highlights of applications of ACT-America data sets.

2.
J Geophys Res Atmos ; 124(2): 1148-1169, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32832312

RESUMO

Emissions of C2-C5 alkanes from the U.S. oil and gas sector have changed rapidly over the last decade. We use a nested GEOS-Chem simulation driven by updated 2011NEI emissions with aircraft, surface and column observations to 1) examine spatial patterns in the emissions and observed atmospheric abundances of C2-C5 alkanes over the U.S., and 2) estimate the contribution of emissions from the U.S. oil and gas industry to these patterns. The oil and gas sector in the updated 2011NEI contributes over 80% of the total U.S. emissions of ethane (C2H6) and propane (C3H8), and emissions of these species are largest in the central U.S. Observed mixing ratios of C2-C5 alkanes show enhancements over the central U.S. below 2 km. A nested GEOS-Chem simulation underpredicts observed C3H8 mixing ratios in the boundary layer over several U.S. regions and the relative underprediction is not consistent, suggesting C3H8 emissions should receive more attention moving forward. Our decision to consider only C4-C5 alkane emissions as a single lumped species produces a geographic distribution similar to observations. Due to the increasing importance of oil and gas emissions in the U.S., we recommend continued support of existing long-term measurements of C2-C5 alkanes. We suggest additional monitoring of C2-C5 alkanes downwind of northeastern Colorado, Wyoming and western North Dakota to capture changes in these regions. The atmospheric chemistry modeling community should also evaluate whether chemical mechanisms that lump larger alkanes are sufficient to understand air quality issues in regions with large emissions of these species.

3.
J Pediatr Urol ; 14(2): 157.e1-157.e8, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29398588

RESUMO

INTRODUCTION: Prior studies of outcomes following genitoplasty have reported high rates of surgical complications among children with atypical genitalia. Few studies have prospectively assessed outcomes after contemporary surgical approaches. OBJECTIVE: The current study reported the occurrence of early postoperative complications and of cosmetic outcomes (as rated by surgeons and parents) at 12 months following contemporary genitoplasty procedures in children born with atypical genitalia. STUDY DESIGN: This 11-site, prospective study included children aged ≤2 years, with Prader 3-5 or Quigley 3-6 external genitalia, with no prior genitoplasty and non-urogenital malformations at the time of enrollment. Genital appearance was rated on a 4-point Likert scale. Paired t-tests evaluated differences in cosmesis ratings. RESULTS: Out of 27 children, 10 were 46,XY patients with the following diagnoses: gonadal dysgenesis, PAIS or testosterone biosynthetic defect, severe hypospadias and microphallus, who were reared male. Sixteen 46,XX congenital adrenal hyperplasia patients were reared female and one child with sex chromosome mosaicism was reared male. Eleven children had masculinizing genitoplasty for penoscrotal or perineal hypospadias (one-stage, three; two-stage, eight). Among one-stage surgeries, one child had meatal stenosis (minor) and one developed both urinary retention (minor) and urethrocutaneous fistula (major) (Summary Figure). Among two-stage surgeries, three children developed a major complication: penoscrotal fistula, glans dehiscence or urethral dehiscence. Among 16 children who had feminizing genitoplasty, vaginoplasty was performed in all, clitoroplasty in nine, external genitoplasty in 13, urethroplasty in four, perineoplasty in five, and total urogenital sinus mobilization in two. Two children had minor complications: one had a UTI, and one had both a mucosal skin tag and vaginal mucosal polyp. Two additional children developed a major complication: vaginal stenosis. Cosmesis scores revealed sustained improvements from 6 months post-genitoplasty, as previously reported, with all scores reported as good or satisfied. DISCUSSION: In these preliminary data from a multi-site, observational study, parents and surgeons were equally satisfied with the cosmetic outcomes 12 months after genitoplasty. A small number of patients had major complications in both feminizing and masculinizing surgeries; two-stage hypospadias repair had the most major complications. Long-term follow-up of patients at post-puberty will provide a better assessment of outcomes in this population. CONCLUSION: In this cohort of children with moderate to severe atypical genitalia, preliminary data on both surgical and cosmetic outcomes were presented. Findings from this study, and from following these children in long-term studies, will help guide practitioners in their discussions with families about surgical management.


Assuntos
Hiperplasia Suprarrenal Congênita/cirurgia , Transtornos do Desenvolvimento Sexual/cirurgia , Anormalidades Urogenitais/cirurgia , Hiperplasia Suprarrenal Congênita/diagnóstico , Pré-Escolar , Estudos de Coortes , Transtornos do Desenvolvimento Sexual/diagnóstico , Estética , Feminino , Genitália Feminina/anormalidades , Genitália Feminina/cirurgia , Genitália Masculina/anormalidades , Genitália Masculina/cirurgia , Humanos , Lactente , Masculino , Complicações Pós-Operatórias , Estudos Prospectivos , Qualidade de Vida , Procedimentos de Cirurgia Plástica/métodos , Medição de Risco , Cirurgia Plástica/métodos , Resultado do Tratamento , Anormalidades Urogenitais/diagnóstico , Procedimentos Cirúrgicos Urogenitais/efeitos adversos , Procedimentos Cirúrgicos Urogenitais/métodos
4.
J Geophys Res Atmos ; 122(19): 10510-10538, 2017 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33006328

RESUMO

Transport is a key parameter in air quality research and plays a dominant role in the Colorado Northern Front Range Metropolitan Area (NFRMA), where terrain induced flows and recirculation patterns can lead to vigorous mixing of different emission sources. To assess different transport processes and their connection to air quality in the NFRMA during the FRAPPÉ and DISCOVER-AQ campaigns in summer 2014, we use the Weather Research and Forecasting Model with inert tracers. Overall, the model represents well the measured winds and the inert tracers are in good agreement with observations of comparable trace gas concentrations. The model tracers support the analysis of surface wind and ozone measurements and allow for the analysis of transport patterns and interactions of emissions. A main focus of this study is on characterizing pollution transport from the NFRMA to the mountains by mountain-valley flows and the potential for recirculating pollution back into the NFRMA. One such event on 12 August 2014 was well captured by the aircraft and is studied in more detail. The model represents the flow conditions and demonstrates that during upslope events, frequently there is a separation of air masses that are heavily influenced by oil and gas emissions to the North and dominated by urban emissions to the South. This case study provides evidence that NFRMA pollution not only can impact the nearby Foothills and mountain areas to the East of the Continental Divide, but that pollution can "spill over" into the valleys to the West of the Continental Divide.

5.
J Pediatr Urol ; 13(1): 28.e1-28.e6, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27887913

RESUMO

INTRODUCTION: Little data exist about the surgical interventions taking place for children with disorders of sex development (DSD). Most studies that have evaluated cosmetic outcomes after genitoplasty have included retrospective ratings by a physician at a single center. OBJECTIVE: The present study aimed to: 1) describe frequency of sex assignment, and types of surgery performed in a cohort of patients with moderate-to-severe genital ambiguity; and 2) prospectively determine cosmesis ratings by parents and surgeons before and after genital surgery. STUDY DESIGN: This prospective, observational study included children aged <2 years of age, with no prior genitoplasty at the time of enrollment, moderate-to-severe genital atypia, and being treated at one of 11 children's hospitals in the United States of America (USA). Clinical information was collected, including type of surgery performed. Parents and the local pediatric urologist rated the cosmetic appearance of the child's genitalia prior to and 6 months after genitoplasty. RESULTS: Of the 37 children meeting eligibility criteria, 20 (54%) had a 46,XX karyotype, 15 (40%) had a 46,XY karyotype, and two (5%) had sex chromosome mosaicism. The most common diagnosis overall was congenital adrenal hyperplasia (54%). Thirty-five children had surgery; 21 received feminizing genitoplasty, and 14 had masculinizing genitoplasty. Two families decided against surgery. At baseline, 22 mothers (63%), 14 fathers (48%), and 35 surgeons (100%) stated that they were dissatisfied or very dissatisfied with the appearance of the child's genitalia. Surgeons rated the appearance of the genitalia significantly worse than mothers (P < 0.001) and fathers (P ≤ 0.001) at baseline. At the 6-month postoperative visit, cosmesis ratings improved significantly for all groups (P < 0.001 for all groups). Thirty-two mothers (94%), 26 fathers (92%), and 31 surgeons (88%) reported either a good outcome, or they were satisfied (see Summary Figure); there were no significant between-group differences in ratings. DISCUSSION: This multicenter, observational study showed surgical interventions being performed at DSD centers in the USA. While parent and surgeon ratings were discordant pre-operatively, they were generally concordant postoperatively. Satisfaction with postoperative cosmesis does not necessarily equate with satisfaction with the functional outcome later in life. CONCLUSION: In this cohort of children with genital atypia, the majority had surgery. Parents and surgeons all rated the appearance of the genitalia unfavorably before surgery, with surgeons giving worse ratings than parents. Cosmesis ratings improved significantly after surgery, with no between-group differences.


Assuntos
Doenças dos Genitais Femininos/cirurgia , Doenças dos Genitais Masculinos/cirurgia , Genitália/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Procedimentos Cirúrgicos Urogenitais , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos
6.
Environ Sci Technol ; 43(7): 2437-42, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19452898

RESUMO

A laser photoacoustic spectroscopy (LPAS) instrument was developed and used for aircraft measurements of ethene from industrial sources near Houston, Texas. The instrument provided 20 s measurements with a detection limit of less than 0.7 ppbv. Data from this instrument and from the GC-FID analysis of air samples collected in flight agreed within 15% on average. Ethene fluxes from the Mt. Belvieu chemical complex to the northeast of Houston were quantified during 10 different flights. The average flux was 520 +/- 140 kg h(-1) in agreement with independent results from solar occultation flux (SOF) measurements, and roughly an order of magnitude higher than regulatory emission inventories indicate. This study shows that ethene emissions are routinely at levels that qualify as emission upsets, which need to be reported to regional air quality managers.


Assuntos
Poluentes Atmosféricos/análise , Etilenos/análise , Análise Espectral/métodos , Acústica
7.
Bioorg Med Chem Lett ; 16(15): 3896-901, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16730987

RESUMO

Synthesis of a series of fused pyrazole tetrahydrofluorenone analogs which are potent, ERbeta subtype selective ligands is described. Analogs possessing subnanomolar ERbeta binding, greater than 100-fold ERbeta-selectivity, and oral bioavailability are reported.


Assuntos
Receptor beta de Estrogênio/efeitos dos fármacos , Fluorenos/química , Pirazóis/química , Animais , Área Sob a Curva , Disponibilidade Biológica , Ciclização , Receptor beta de Estrogênio/metabolismo , Fluorenos/sangue , Fluorenos/metabolismo , Ratos
9.
J Cell Physiol ; 206(2): 420-7, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16206243

RESUMO

We describe a novel human gene, named SEL-OB/SVEP1, expressed by skeletal tissues in vivo and by cultured osteogenic cells. The mRNA expression was analyzed on frozen tissues retrieved by laser-capture microscope dissection (LCM) and was detected in osteogenic tissues (periosteum and bone) but not in cartilage or skeletal muscle. The SEL-OB/SVEP1 cDNA of 11,139 bp was in silico translated into a 3574AA protein with expected molecular weight of 370 kDa. The protein is composed of multiple domains including complement control protein (CCP) modules with selectin superfamily signature; sushi and other domains, such as vWA, EGF, PTX, and HYR. Stromal osteogenic cells were analyzed for the protein expression using anti-SEL-OB/SVEP1 for immuno-precipitation and Western blot application confirm the presence of high molecular weight protein. Immuno-histochemistry and fluorescence-activated cell sorting (FACS) were applied to detect SEL-OB/SVEP1 on the surface of stromal cells. ELISA quantified the dependence of protein expression on cell density. Bioinformatic analysis of SEL-OB/SVEP1 revealed domains compositions recognized in cell surface molecules and suggested its role in cell adhesion. Analysis of mesechymal osteogenic cells' adhesion in presence of anti-SEL-OB/SVEP1 antibody demonstrated its interference with initial adhesion stages. In summary, present study describes novel SEL-OB/SVEP1 protein with a unique composition of functional domains, restricted pattern of expression in skeletal cells and demonstrated involvement in attachment of mesenchymal cells. The unusual composition of functional domains puts SEL-OB/SVEP1 in the discrete new group of membrane proteins involved in cell adhesion processes. All together makes SEL-OB/SVEP1 an attractive marker for studying the role of stromal osteogenic cells and their interactions within the bone marrow microenvironment creating a network that regulates the skeletal homeostasis.


Assuntos
Células da Medula Óssea/metabolismo , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/genética , Proteínas de Membrana/química , Proteínas de Membrana/genética , Osteoblastos/metabolismo , Animais , Sequência de Bases , Adesão Celular , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Citometria de Fluxo , Humanos , Proteínas de Membrana/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Dados de Sequência Molecular , Ratos , Homologia de Sequência , Células Estromais/metabolismo
10.
Thorac Cardiovasc Surg ; 53(4): 223-5, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16037867

RESUMO

We present the case of a 23-year-old African professional footballer who was admitted on April 1, 1999 to the Cardiology Department of the University Hospital in Magdeburg, on an emergency basis, from a regional lung clinic. According to the history, he was involved in a collision with an opposing player during a football match in his country (in Africa). He lost consciousness for a short time, but continued playing to the end of the match. About two months later he was invited by a German football club for a check-up, with the view to ultimately playing for the club. The team did not find him physically fit enough to play professional football, so he decided to go to Paris by bus on March 31, 1999. During the journey he suddenly became cardio-pulmonary decompensated and had to undergo cardio-pulmonary resuscitation (CPR). He was intubated and placed on a respirator and immediately transferred to a nearby lung clinic. From the lung clinic he was transferred to the Intensive Care Unit of the Cardiology Department of the Magdeburg University Hospital, on April 1, 1999 as an emergency case. He was intensively treated with catecholamines, intravenous ACE inhibitors and diuretics. His clinical condition did not improve appreciably. His chest X-ray showed extreme dilatation of the right and left heart as well as extreme pulmonary congestion.


Assuntos
Falso Aneurisma/cirurgia , Aorta , Insuficiência da Valva Aórtica/cirurgia , Futebol Americano/lesões , Valva Mitral/cirurgia , Adulto , Falso Aneurisma/diagnóstico por imagem , Insuficiência da Valva Aórtica/diagnóstico por imagem , Traumatismos em Atletas/diagnóstico , Traumatismos em Atletas/cirurgia , Terapia Combinada , Ecocardiografia Transesofagiana , Eletrocardiografia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/cirurgia , Testes de Função Cardíaca , Hemodinâmica/fisiologia , Humanos , Masculino , Monitorização Fisiológica , Marca-Passo Artificial , Prognóstico , Procedimentos de Cirurgia Plástica/métodos , Recuperação de Função Fisiológica , Medição de Risco
11.
J Cell Biochem ; 90(2): 347-60, 2003 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-14505351

RESUMO

We studied the beneficial effects of dietary consumption of n-3 polyunsaturated fatty acids (PUFA) and two selective estrogen receptor modulator (SERM) derivatives (SERM-I and SERM-II) and their combined effect on serum lipids, skin dermis and adipose layers, bone marrow adipogenesis, and cytokine secretion in mice. Two different ovariectomized (OVX) models were studied: treatment began immediately post-OVX in one and 3 months post-OVX in the other. Our results showed that n-3 PUFA and both SERMs decreased triglyceride levels in the serum, and that SERMs also decreased serum cholesterol levels while n-3 PUFA had no similar effect. SERMs had no effect on IL-6, IL-1 beta, or IL-10 levels, but they decreased ex vivo tumor necrosis factor (TNF-alpha). N-3 PUFA decreased secretion of non-induced IL-6 and TNF-alpha from cultured BMC and IL-1 beta levels in vivo (i.e., in bone marrow plasma), but its main effect was a significant elevation in the secretion of IL-10, a known anti-inflammatory cytokine. OVX-induced B-lymphopoiesis was not affected by LY-139481 (SERM-I) while LY-353381 (SERM-II) exhibited an estrogen-antagonistic effect in sham and OVX mice and elevated the amount of B-cells in bone marrow. Fish oil consumption prevented the elevation in B-lymphopoiesis caused by OVX, but had no curative effect on established augmented B-lymphopoiesis. This activity could be mediated via the elevation of IL-10 which was shown to suppress B-lymphopoiesis. Both SERMs and n-3 PUFA inhibited the increase in adipose tissue thickness caused by OVX in mice. Our results showed that n-3 PUFA, could prevent some of the deleterious outcomes of estrogen deficiency that were not affected by SERMs. We observed no significant beneficial effects of the combined administration of SERM-I, SERM-II, and PUFA on the studied parameters.The exact mechanism by which polyunsaturated fatty acids exert their activities is still not clear, but peroxisome proliferator-activated receptors (PPARs) might be involved in processes which are modulated by n-3 PUFA.


Assuntos
Ácidos Graxos Insaturados/farmacologia , Hipolipemiantes/farmacologia , Ovariectomia , Ovário/fisiologia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Triglicerídeos/farmacologia , Tecido Adiposo/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Colesterol/sangue , Ácidos Graxos Ômega-3 , Feminino , Óleos de Peixe , Interleucina-1/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Piperidinas/farmacologia , Cloridrato de Raloxifeno/farmacologia , Pele/efeitos dos fármacos , Pele/metabolismo , Baço/metabolismo , Tiofenos/farmacologia , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/metabolismo
12.
J Environ Monit ; 5(1): 68-74, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12619758

RESUMO

Emissions of volatile chemicals control the hydroxyl radical (OH), the atmosphere's main cleansing agent, and thus the production of secondary pollutants. Accounting for all of these chemicals can be difficult, especially in environments with mixed urban and forest emissions. The first direct measurements of the atmospheric OH reactivity, the inverse of the OH lifetime, were made as part of the Southern Oxidant Study (SOS) at Cornelia Fort Airpark in Nashville, TN in summer 1999. Measured OH reactivity was typically 11 s(-1). Measured OH reactivity was 1.4 times larger than OH reactivity calculated from the sum of the products of measured chemical concentrations and their OH reaction rate coefficients. This difference is statistically significant at the 1sigma uncertainty level of both the measurements and the calculations but not the 2sigma uncertainty level. Measured OH reactivity was 1.3 times larger than the OH reactivity from a model that uses measured ambient concentrations of volatile organic compounds (VOCs), NO, NO2, SO2, and CO. However, it was within approximately 10% of the OH reactivity from a model that includes hydrocarbon measurements made in a Nashville tunnel and scaled to the ambient CO at Cornelia Fort Airpark. These comparisons indicate that 30% of the OH reactivity in Nashville may come from short-lived highly reactive VOCs that are not usually measured in field intensive studies or by US EPA's Photochemical Assessment Monitoring Stations.


Assuntos
Poluentes Atmosféricos/análise , Radical Hidroxila/análise , Radical Hidroxila/química , Oxidantes/análise , Oxidantes/química , Cidades , Monitoramento Ambiental , Compostos Orgânicos , Estações do Ano , Tennessee , Árvores , Volatilização
13.
J Epidemiol Community Health ; 56(8): 631-6, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12118057

RESUMO

STUDY OBJECTIVE: s: Depression and falls are two common conditions that impair the health of older people. Both are relatively underdiagnosed and undertreated problems in primary care. The study objective was to investigate whether there was a common set of risk factors that could predict an increased risk of both falls and depression. DESIGN: This was a cohort study drawn from a primary care clinic, with a one year follow up. Dependent measures included: reporting two or more falls in the past year and a score of 7 or over on the S-GDS (Short Geriatric Depression Scale). A parsimonious set of risk factors was selected that predicted both outcomes based on a series of discriminant function analyses. PARTICIPANTS AND SETTING: The setting was a primary care clinic serving a mixed socioeconomic population, in Beer Sheva, Israel. The sample included 283 General Sick Fund members, aged 60 and over, who completed both baseline assessments and one year follow up interviews. MAIN RESULTS: At the one year follow up, 12% of the sample reported frequent falls in the past year and 25.5% of the sample screened positive for depressive symptoms. A set of five risk factors that included: poor self rated health, poor cognitive status, impaired ADL, two or more clinic visits in the past month, and slow walking speed (g10 seconds over five metres) was successful at discriminating between fallers and non-fallers (86% discrimination) and between those with and without depressive symptoms (76%). For every risk factor added, there was a significant increase in the proportion of respondents who had depressive symptoms. A similar result was found for falls. CONCLUSIONS: These results show that there is a common set of risk factors that increase the risk of two common outcomes in geriatric medicine, falls and depression. For a general practitioner or a geriatric physician, it might be easier to detect these risk factors than to diagnose depression or high risk for falls. When these risk factors are detected in patients the physician can then be more active in direct probing about depression and falls.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Transtorno Depressivo/etiologia , Avaliação Geriátrica , Medição de Risco , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Indicadores Básicos de Saúde , Humanos , Israel/epidemiologia , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Fatores de Risco
14.
Appl Phys B ; 75(2-3): 281-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12599397

RESUMO

The development of a compact tunable mid-IR laser system at 3.5 micrometers for quantitative airborne spectroscopic trace gas absorption measurements is reported. The mid-IR laser system is based on difference frequency generation (DFG) in periodically poled LiNbO3 and utilizes optical fiber amplified near-IR diode and fiber lasers as pump sources operating at 1083 nm and 1562 nm, respectively. This paper describes the optical sensor architecture, performance characteristics of individual pump lasers and DFG, as well as its application to wavelength modulation spectroscopy employing an astigmatic Herriott multi-pass gas absorption cell. This compact system permits detection of formaldehyde with a minimal detectable concentration (1 sigma replicate precision) of 74 parts-per-trillion by volume (pptv) for 1 min of averaging time and was achieved using calibrated gas standards, zero air background and rapid dual-beam subtraction. This corresponds to a pathlength-normalized replicate fractional absorption sensitivity of 2.5 x 10-(10 )cm-1.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental/instrumentação , Lasers , Espectrofotometria Infravermelho/instrumentação , Atmosfera/química , Monitoramento Ambiental/métodos , Desenho de Equipamento , Estudos de Avaliação como Assunto , Tecnologia de Fibra Óptica , Formaldeído/análise , Nióbio , Distribuição Normal , Fibras Ópticas , Óxidos
15.
Transplantation ; 72(12): 1974-82, 2001 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-11773898

RESUMO

BACKGROUND: In vitro, soluble MHC (sMHC) antigens modulate and induce apoptosis in alloreactive and antigen-specific T cells, demonstrating their potency to regulate T cell-mediated immune responses. However, their efficacy to regulate immunological responses in vivo remains unclear. Here, we report that repetitive intraperitoneal injection of recombinant Lewis rat-derived MHC class I antigens in Dark Agouti (DA) rats modulates alloreactivity. METHODS: RT1.A1 (Lewis derived) genes were cloned into mammalian expression vectors, and RT1.Aa (DA derived) genes were used to transfect a rat myeloma cell line. RT1.A1 molecules were injected intraperitoneally in DA recipients that subsequently underwent transplantation with Lewis-derived cardiac allografts. RESULTS: Soluble class I antigens were secreted by the transfected cells and were shown to be heterodimeric, peptide-loaded, and conformationally folded. Injection of donor-derived soluble MHC significantly reduced the ability of recipient animals to mount a cytotoxic T-cell response to donor-derived tissue. More interestingly, this treatment significantly prolonged donor-graft survival and allowed 60% of treated animals to develop graft tolerance (>120 days), when donor sMHC were combined with a single subtherapeutic dosage of cyclosporine. Thymectomy of recipient animals before transplantation did not interfere with induction of peripheral tolerance. CONCLUSIONS: Donor-derived sMHC are potential tolerogens for down-regulating the cytotoxic T-cell response of animals that undergo transplantation. Thus, these data provide for the first time a rationale for the application of directly injected sMHC in vivo to down-regulate immunological responses and aid the induction of graft tolerance.


Assuntos
Ciclosporina/administração & dosagem , Transplante de Coração/imunologia , Antígenos de Histocompatibilidade Classe I/farmacologia , Imunossupressores/administração & dosagem , Linfócitos T/fisiologia , Doadores de Tecidos , Tolerância ao Transplante , Animais , Formação de Anticorpos , Apoptose , Linfócitos T CD4-Positivos/patologia , Ciclosporina/farmacologia , Relação Dose-Resposta a Droga , Regulação para Baixo , Sobrevivência de Enxerto/efeitos dos fármacos , Antígenos de Histocompatibilidade/metabolismo , Imunossupressores/farmacologia , Isoanticorpos/biossíntese , Miocárdio/patologia , Ratos , Ratos Endogâmicos Lew , Ratos Endogâmicos , Linfócitos T/efeitos dos fármacos , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/fisiologia , Timo/fisiologia , Transfecção , Células Tumorais Cultivadas
16.
Minim Invasive Neurosurg ; 43(4): 190-1, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11270829

RESUMO

We present an infant who underwent endoscopic third ventriculostomy due to symptomatic hydrocephalus secondary to aqueductal stenosis. This is the first reported case of inappropriate secretion of antidiuretic hormone complicated by hyponatriemia and seizures following endoscopic surgery. The possibility of such a neuroendoscopic complication should alert neurosurgeons and close observation of serum electrolytes is highly recommended in the acute postoperative period, particularly in infants.


Assuntos
Endoscopia , Hidrocefalia/cirurgia , Hiponatremia/etiologia , Síndrome de Secreção Inadequada de HAD/etiologia , Complicações Pós-Operatórias/etiologia , Convulsões/etiologia , Terceiro Ventrículo/cirurgia , Ventriculostomia , Traumatismos Cranianos Fechados/complicações , Traumatismos Cranianos Fechados/diagnóstico por imagem , Traumatismos Cranianos Fechados/cirurgia , Humanos , Hidrocefalia/diagnóstico por imagem , Hiponatremia/diagnóstico por imagem , Síndrome de Secreção Inadequada de HAD/diagnóstico por imagem , Lactente , Masculino , Complicações Pós-Operatórias/diagnóstico por imagem , Convulsões/diagnóstico por imagem , Terceiro Ventrículo/diagnóstico por imagem , Tomografia Computadorizada por Raios X
17.
Appl Opt ; 39(24): 4436-43, 2000 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-11543547

RESUMO

High-sensitivity detection of formaldehyde (CH2O) at 3.5315 micrometers (2831.64 cm-1) is reported with a diode-laser-pumped, fiber-coupled, periodically poled LiNbO3 spectroscopic source. This source replaced the Pb-salt diode laser Dewar assembly of an existing tunable diode-laser absorption spectrometer designed for ultrasensitive detection of CH2O. Spectra are recorded with 2f-modulation spectroscopy and zero-air rapid background subtraction. Initial measurements reported here, determined from multiple measurements of a flowing 7.7 parts per billion by volume (ppbv, parts in 10(9)) CH2O in air mixture, indicate replicate precisions as low as 0.24 ppbv.


Assuntos
Atmosfera/química , Monitoramento Ambiental/instrumentação , Formaldeído/análise , Lasers , Espectrofotometria Infravermelho/instrumentação , Desenho de Equipamento , Estudos de Avaliação como Assunto , Chumbo
18.
Pediatr Neurosurg ; 30(3): 132-4, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10352415

RESUMO

Gangliogliomas are generally considered benign tumors. Although more commonly found in the brain, spinal cord ganglioglioma is a well established, albeit infrequent, entity. We describe a 2-decade clinical course of a patient initially diagnosed with a thoracolumbar 'glial-neuronal hamartoma' at age 4. Seventeen years after his first operation, local recurrence was noted. Despite subsequent multiple gross total resections and adjuvant therapy, histologic features became increasingly ominous and ultimately proved fatal. This is an unusual report and histologic presentation of a resected spinal cord ganglioglioma recurring as an anaplastic ependymoma/astrocytoma and subsequently a glioblastoma. It is quite likely that the originally resected ganglioglioma was actually part of a primitive neuroectodermal tumor which had undergone extensive maturation.


Assuntos
Transformação Celular Neoplásica , Ganglioglioma/patologia , Glioma/patologia , Hamartoma/patologia , Segunda Neoplasia Primária , Doenças da Medula Espinal/patologia , Neoplasias da Medula Espinal/patologia , Adulto , Pré-Escolar , Ependimoma/patologia , Ependimoma/cirurgia , Evolução Fatal , Ganglioglioma/cirurgia , Glioblastoma/patologia , Glioblastoma/cirurgia , Hamartoma/cirurgia , Humanos , Masculino , Recidiva Local de Neoplasia , Tumores Neuroectodérmicos Primitivos/patologia , Doenças da Medula Espinal/cirurgia , Neoplasias da Medula Espinal/cirurgia
19.
J Card Fail ; 5(1): 8-16, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10194655

RESUMO

BACKGROUND: The rate of left ventricular (LV) pressure increase (LV + dP/dt) may be related to QRS duration, as well as to a number of hemodynamic parameters. METHODS AND RESULTS: We studied the relation between basal LV + dP/dt and QRS duration in 43 patients with normal LV function and 81 patients with heart failure undergoing diagnostic catheterization. We also examined the relationship between LV + dP/dt and heart rate, as well as measures of both LV preload and afterload. In patients with normal LV function, there was a strong relationship between basal LV + dP/dt and resting heart rate, whereas the relationship with QRS duration was of borderline significance. In patients with heart failure, the relationship with heart rate was lost; however, LV systolic pressure, QRS duration, and LV end-diastolic pressure all made significant contributions to a model predicting LV + dP/dt. CONCLUSIONS: These data show a strong relationship between resting heart rate and LV + dP/dt in the healthy human LV. In patients with heart failure, the relationship with heart rate is not maintained; however, there is a systematic relationship between LV + dP/dt and both the time-course of the electrical activation and measures of LV loading conditions.


Assuntos
Sistema de Condução Cardíaco/fisiologia , Função Ventricular Esquerda/fisiologia , Idoso , Pressão Sanguínea , Feminino , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Disfunção Ventricular Esquerda/fisiopatologia
20.
Science ; 281(5376): 517, 1998 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-9705720
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