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1.
Sci Rep ; 8(1): 4669, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29549350

RESUMO

The East Asian Summer Monsoon driven by temperature and moisture gradients between the Asian continent and the Pacific Ocean, leads to approximately 50% of the annual rainfall in the region across 20-40°N. Due to its increasing scientific and social importance, there have been several previous studies on identification of moisture sources for summer monsoon rainfall over East Asia mainly using Lagrangian or Eulerian atmospheric water vapor models. The major source regions for EASM previously proposed include the North Indian Ocean, South China Sea and North western Pacific. Based on high-precision and high-frequency 6-year measurement records of hydrofluorocarbons (HFCs), here we report a direct evidence of rapid intrusion of warm and moist tropical air mass from the Southern Hemisphere (SH) reaching within a couple of days up to 33°N into East Asia. We further suggest that the combination of direct chemical tracer record and a back-trajectory model with physical meteorological variables helps pave the way to identify moisture sources for monsoon rainfall. A case study for Gosan station (33.25°N, 126.19°E) indicates that the meridional transport of precipitable water from the SH accompanying the southerly/southwesterly flow contributes most significantly to its summer rainfall.

2.
Front Microbiol ; 8: 2280, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29238325

RESUMO

Probiotics are live microorganisms that confer benefits to the host health. The infection rate of potentially pathogenic organisms such as Candida albicans, the most common agent associated with mucosal candidiasis, can be reduced by probiotics. However, the mechanisms by which the probiotics interfere with the immune system are largely unknown. We evaluated the effect of probiotic bacteria on C. albicans challenged human macrophages. Macrophages were pretreated with lactobacilli alone (Lactobacillus rhamnosus LR32, Lactobacillus casei L324m, or Lactobacillus acidophilus NCFM) or associated with Escherichia coli lipopolysaccharide (LPS), followed by the challenge with C. albicans or LPS in a co-culture assay. The expression of pattern-recognition receptors genes (CLE7A, TLR2, and TLR4) was determined by RT-qPCR, and dectin-1 reduced levels were confirmed by flow cytometry. The cytokine profile was determined by ELISA using the macrophage cell supernatant. Overall probiotic lactobacilli down-regulated the transcription of CLEC7A (p < 0.05), resulting in the decreased expression of dectin-1 on probiotic pretreated macrophages. The tested Lactobacillus species down-regulated TLR4, and increased TLR2 mRNA levels in macrophages challenged with C. albicans. The cytokines profile of macrophages challenged with C. albicans or LPS were altered by the probiotics, which generally led to increased levels of IL-10 and IL-1ß, and reduction of IL-12 production by macrophages (p < 0.05). Our data suggest that probiotic lactobacilli impair the recognition of PAMPs by macrophages, and alter the production of pro/anti-inflammatory cytokines, thus modulating inflammation.

3.
Bull Am Meteorol Soc ; 98(1): 106-128, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29636590

RESUMO

The Convective Transport of Active Species in the Tropics (CONTRAST) experiment was conducted from Guam (13.5° N, 144.8° E) during January-February 2014. Using the NSF/NCAR Gulfstream V research aircraft, the experiment investigated the photochemical environment over the tropical western Pacific (TWP) warm pool, a region of massive deep convection and the major pathway for air to enter the stratosphere during Northern Hemisphere (NH) winter. The new observations provide a wealth of information for quantifying the influence of convection on the vertical distributions of active species. The airborne in situ measurements up to 15 km altitude fill a significant gap by characterizing the abundance and altitude variation of a wide suite of trace gases. These measurements, together with observations of dynamical and microphysical parameters, provide significant new data for constraining and evaluating global chemistry climate models. Measurements include precursor and product gas species of reactive halogen compounds that impact ozone in the upper troposphere/lower stratosphere. High accuracy, in-situ measurements of ozone obtained during CONTRAST quantify ozone concentration profiles in the UT, where previous observations from balloon-borne ozonesondes were often near or below the limit of detection. CONTRAST was one of the three coordinated experiments to observe the TWP during January-February 2014. Together, CONTRAST, ATTREX and CAST, using complementary capabilities of the three aircraft platforms as well as ground-based instrumentation, provide a comprehensive quantification of the regional distribution and vertical structure of natural and pollutant trace gases in the TWP during NH winter, from the oceanic boundary to the lower stratosphere.

4.
Int J Obes (Lond) ; 40(10): 1566-1573, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27273607

RESUMO

BACKGROUND/OBJECTIVES: The use of bisphenol A (BPA) in consumer products and food packaging has been associated under certain conditions with a risk of negative health outcomes. This prompted its removal from many products and replacement with structural analogs. Bisphenol S (BPS) is one such analog, but its metabolic effects have not been fully characterized. The objective of our study was to determine whether BPS functions similarly to BPA at inducing adipogenesis. METHODS: Murine 3T3-L1 preadipocytes were used to evaluate and compare the adipogenic potential of BPS to BPA. Cells were treated with 0.01-50 µM BPS or 0.01-50 µM BPA and adipogenic effects were measured. Further, their ability to activate peroxisome proliferator-activated receptor gamma (PPARγ), an adipogenic transcription factor, was also determined. RESULTS: Our results indicate that treatment of 3T3-L1 cells with BPS induced lipid accumulation and increased mRNA and protein expression of key adipogenic markers (1-50 µM; P<0.05). BPS treatment resulted in a higher expression of adipogenic markers as well as greater lipid accumulation when compared with BPA treatment. We showed that BPS can upregulate lipoprotein lipase, adipocyte protein 2, PPARγ, perilipin, adipsin and CCAAT/enhancer-binding protein alpha mRNA expression levels. Furthermore, using transcriptional assays, we showed that BPS and BPA can modestly activate PPARγ using a PPRE (PPARγ response element)-dependent luciferase construct by 1.5-fold (P<0.05). However, BPS but not BPA was able to competitively inhibit rosiglitazone (ROSI)-activated PPARγ, suggesting that BPS interacts with PPARγ distinctly from BPA. Co-treatment of cells with the selective PPARγ antagonist GW9662 inhibits BPS-, BPA-, ROSI- but not dexamethasone-dependent adipogenic differentiation. CONCLUSIONS: Both BPA and BPS can enhance 3T3-L1 adipocyte differentiation in a dose-dependent manner and require PPARγ to induce adipogenesis. Through direct comparison, we show that BPS is a more potent adipogen than BPA.


Assuntos
Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Compostos Benzidrílicos/farmacologia , PPAR gama/metabolismo , Fenóis/farmacologia , Células-Tronco/efeitos dos fármacos , Sulfonas/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Western Blotting , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Camundongos , Células-Tronco/citologia , Células-Tronco/metabolismo
5.
J Prosthodont ; 24(3): 194-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25143068

RESUMO

PURPOSE: The prevalence of Candida infections has been rising with an increasingly aging population and a larger population of immunocompromised individuals. The use of probiotics may be an alternative approach to antifungal agents in the prevention and treatment of oral candidiasis. This study aimed to evaluate the short-term effect of probiotics in reducing the infection level of oral Candida in candidiasis-asymptomatic elderly denture wearers. MATERIALS AND METHODS: In a double-blind randomized study, 59 denture wearers harboring Candida spp. in the oral cavity with no clinical symptoms were allocated into two groups: probiotic and placebo. All patients were instructed to clean the denture daily. The probiotic group poured a capsule containing lyophilized Lactobacillus rhamnosus HS111, Lactobacillus acidophillus HS101, and Bifidobacterium bifidum daily on the palatal surface of the maxillary denture, whereas the placebo group was submitted to the same regimen using placebo capsules. Candida spp. infection levels were evaluated in palate mucosa samples obtained before and after a 5-week experimental period. RESULTS: All patients harbored Candida in the palate mucosa at baseline. Fifty-five individuals completed the experimental period. The detection rate of Candida spp. was 92.0% in the placebo group after the experimental period, whereas it was reduced to 16.7% in the probiotic group. The reduction promoted by the probiotic regimen was independent of baseline characteristics such as Candida infection level and colonizing species, age of denture, and other variables. CONCLUSION: The probiotic product was effective in reducing the colonization of the oral cavity with Candida in candidiasis-asymptomatic elderly denture wearers, suggesting that this multispecies probiotic could be used to prevent oral candidiasis. CLINICAL IMPLICATIONS: Colonization of oral surfaces by Candida is considered a risk factor for invasive fungal infections. The use of a product with L. rhamnosus, L. acidophilus, and B. bifidum may represent an alternative treatment for reduction of Candida infections in elderly denture wearers.


Assuntos
Candida/efeitos dos fármacos , Candidíase Bucal/prevenção & controle , Candidíase Bucal/terapia , Dentaduras/microbiologia , Boca/microbiologia , Probióticos/uso terapêutico , Idoso , Bifidobacterium bifidum , Brasil , Desgaste de Restauração Dentária/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Lactobacillus acidophilus , Lacticaseibacillus rhamnosus , Masculino , Pessoa de Meia-Idade , Palato/microbiologia
6.
Geophys Res Lett ; 42(11): 4573-4580, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-27570318

RESUMO

We have developed a chemical mechanism describing the tropospheric degradation of chlorine containing very short-lived substances (VSLS). The scheme was included in a global atmospheric model and used to quantify the stratospheric injection of chlorine from anthropogenic VSLS ( ClyVSLS) between 2005 and 2013. By constraining the model with surface measurements of chloroform (CHCl3), dichloromethane (CH2Cl2), tetrachloroethene (C2Cl4), trichloroethene (C2HCl3), and 1,2-dichloroethane (CH2ClCH2Cl), we infer a 2013 ClyVSLS mixing ratio of 123 parts per trillion (ppt). Stratospheric injection of source gases dominates this supply, accounting for ∼83% of the total. The remainder comes from VSLS-derived organic products, phosgene (COCl2, 7%) and formyl chloride (CHClO, 2%), and also hydrogen chloride (HCl, 8%). Stratospheric ClyVSLS increased by ∼52% between 2005 and 2013, with a mean growth rate of 3.7 ppt Cl/yr. This increase is due to recent and ongoing growth in anthropogenic CH2Cl2-the most abundant chlorinated VSLS not controlled by the Montreal Protocol.

7.
Nature ; 513(7517): 219-23, 2014 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-25209800

RESUMO

The hydroxyl radical (OH) is a key oxidant involved in the removal of air pollutants and greenhouse gases from the atmosphere. The ratio of Northern Hemispheric to Southern Hemispheric (NH/SH) OH concentration is important for our understanding of emission estimates of atmospheric species such as nitrogen oxides and methane. It remains poorly constrained, however, with a range of estimates from 0.85 to 1.4 (refs 4, 7-10). Here we determine the NH/SH ratio of OH with the help of methyl chloroform data (a proxy for OH concentrations) and an atmospheric transport model that accurately describes interhemispheric transport and modelled emissions. We find that for the years 2004-2011 the model predicts an annual mean NH-SH gradient of methyl chloroform that is a tight linear function of the modelled NH/SH ratio in annual mean OH. We estimate a NH/SH OH ratio of 0.97 ± 0.12 during this time period by optimizing global total emissions and mean OH abundance to fit methyl chloroform data from two surface-measurement networks and aircraft campaigns. Our findings suggest that top-down emission estimates of reactive species such as nitrogen oxides in key emitting countries in the NH that are based on a NH/SH OH ratio larger than 1 may be overestimated.


Assuntos
Atmosfera/química , Radical Hidroxila/química , Modelos Teóricos , Poluentes Atmosféricos/química , Clorofórmio/química , Simulação por Computador , Óxidos de Nitrogênio/química
8.
Nutr Diabetes ; 4: e102, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24418828

RESUMO

BACKGROUND: Obesity is a major health concern in the developed world, and increasing evidence suggests that exposures to common environmental substances may enhance the risk for the development of this disease. OBJECTIVES: The current study examines the effect of the ubiquitous plastic monomer bisphenol A (BPA) on the differentiation of primary human preadipocytes in vitro and the role of the estrogen and glucocorticoid receptors. METHODS: In this study, the mechanism of BPA-induced adipogenesis in preadipocytes from donors with healthy body mass index in the absence of exogenous glucocorticoid was evaluated. The effects of estradiol, the estrogen-receptor (ER) antagonist ICI and the glucocorticoid receptor (GR) antagonist RU486 on BPA-induced adipogenesis were examined. The expression levels of key adipogenic factors were assessed. RESULTS: Treatment of preadipocytes with 1-50 µM BPA induced a dose-dependent increase in differentiation and lipid accumulation as determined by lipid staining and triacylglyceride quantification. BPA also induced expression of the adipogenic markers aP2, adipsin, peroxisome proliferator-activated receptor γ and the CCAAT-enhancer-binding proteins α and ß. Co-treatment of cells with ICI inhibited the BPA-induced increase in aP2 levels, while treatment with ICI or estradiol alone had no effect. Treatment of cells with the GR antagonist RU486 had no effect on BPA-induced differentiation as evaluated by aP2 levels. CONCLUSIONS: This study is one of the first to show that BPA induces human adipocyte differentiation in the absence of exogenous glucocorticoid through a non-classical ER pathway rather than through GR activation. These studies add to the growing evidence that endocrine-disrupting chemicals such as BPA have the potential to modulate adipogenesis and impact human biology.

9.
Science ; 331(6022): 1295-9, 2011 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-21393539

RESUMO

A large fraction of atmospheric aerosols are derived from organic compounds with various volatilities. A National Oceanic and Atmospheric Administration (NOAA) WP-3D research aircraft made airborne measurements of the gaseous and aerosol composition of air over the Deepwater Horizon (DWH) oil spill in the Gulf of Mexico that occurred from April to August 2010. A narrow plume of hydrocarbons was observed downwind of DWH that is attributed to the evaporation of fresh oil on the sea surface. A much wider plume with high concentrations of organic aerosol (>25 micrograms per cubic meter) was attributed to the formation of secondary organic aerosol (SOA) from unmeasured, less volatile hydrocarbons that were emitted from a wider area around DWH. These observations provide direct and compelling evidence for the importance of formation of SOA from less volatile hydrocarbons.

10.
Int J Clin Pract Suppl ; (170): 20-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21323809

RESUMO

Closed-loop algorithms can be found in every aspect of everyday modern life. Automation and control are used constantly to provide safety and to improve quality of life. Closed-loop systems and algorithms can be found in home appliances, automobiles, aviation and more. Can one imagine nowadays driving a car without ABS, cruise control or even anti-sliding control? Similar principles of automation and control can be used in the management of diabetes mellitus (DM). The idea of an algorithmic/technological way to control glycaemia is not new and has been researched for more than four decades. However, recent improvements in both glucose-sensing technology and insulin delivery together with advanced control and systems engineering made this dream of an artificial pancreas possible. The artificial pancreas may be the next big step in the treatment of DM since the use of insulin analogues. An artificial pancreas can be described as internal or external devices that use continuous glucose measurements to automatically manage exogenous insulin delivery with or without other hormones in an attempt to restore glucose regulation in individuals with DM using a control algorithm. This device as described can be internal or external; can use different types of control algorithms with bi-hormonal or uni-hormonal design; and can utilise different ways to administer them. The different designs and implementations have transitioned recently from in silico simulations to clinical evaluation stage with practical applications in mind. This may mark the beginning of a new era in diabetes management with the introduction of semi-closed-loop systems that can prevent or minimise nocturnal hypoglycaemia, to hybrid systems that will manage blood glucose (BG) levels with minimal user intervention to finally fully automated systems that will take the user out of the loop. More and more clinical trials will be needed for the artificial pancreas to become a reality but initial encouraging results are proof that we are on the right track. We attempted to select recent publications that will present these current achievements in the quest for the artificial pancreas and that will inspire others to continue to progress this field of research.


Assuntos
Diabetes Mellitus/terapia , Sistemas de Infusão de Insulina , Pâncreas Artificial , Humanos , Bombas de Infusão Implantáveis
11.
Rev. odontol. Univ. Cid. Sao Paulo ; 22(3): 240-246, set.-dez. 2010.
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-574613

RESUMO

A osseointegração é, sem sombra de dúvida, a responsável pelo notável avanço tecnológico, mudança deconceitos filosóficos e condução de planejamentos voltados à reabilitação oral, como também, pela disseminaçãoe propagação dos conhecimentos, interferindo sobremaneira nas demais áreas da Odontologia contemporânea.Os implantes osseointegrados são cada vez mais utilizados para substituir dentes perdidos em várias situações, desde a perda de um único dente até em casos de completo edentulismo. A reabilitação de pacientes desdentados com próteses fixas ou overdentures removíveis é um processo complexo e desafiador. Existem fatores cruciais para a decisão de uma prótese fixa ou removível para se obter estética, fonética, promover conforto e função. Além disso, o resultado do tratamento está relacionado à taxa de sobrevivência dos implantes, à manutenção do osso marginal, à saúde do tecido periimplantar, à longevidade dos componentes protéticos e da prótese em si. Esse estudo buscou analisar as vantagens e desvantagens das reabilitações protéticas sobre implantes, fixas e removíveis, para pacientes totalmente desdentados.


Doubtless, osseointegration is the major responsible for the remarkable technological advance, changing philosophical concepts and guiding treatment plans related to oral rehabilitation. It also contributes to knowledge spread and diffusion, interfering in other areas of contemporary dentistry. Osseointegrated implants are widelyused to replace lost teeth in many situations, since the loss of a single tooth to completely edentulous archcases. Rehabilitation of edentulous patients by using fixed or removable implant-supported prostheses is a complex and challenging procedure. There are crucial factors involved at the decision of whether fixed or removable implant prosthesis should be planned to acquire optimal esthetics, phonetics, comfort, and function. In addition, the treatment result is related to implant survival, crest bone loss, soft tissue health, prosthesis's components longevity and prosthesis longevity itself. The aim of the present study is analyze the advantages and disadvantages of prosthetic rehabilitation of completely edentulous patients with fixed or removable implants.


Assuntos
Arcada Edêntula/diagnóstico , Implantes Dentários , Prótese Total
12.
Int J Clin Pract Suppl ; (166): 20-5, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20377660

RESUMO

The dream of closing the loop is actually the dream of creating an artificial pancreas and freeing the patients from being involved with the care of their own diabetes. Insulin-dependent diabetes (type 1) is a chronic incurable disease which requires constant therapy without the possibility of any 'holidays' or insulin-free days. It means that patients have to inject insulin every day of their life, several times per day, and in order to do it safely they also have to measure their blood glucose levels several times per day. Patients need to plan their meals, their physical activities and their insulin regime - there is only very small room for spontaneous activities. This is why the desire for an artificial pancreas is so strong despite the fact that it will not cure the diabetic patients. Attempts to develop a closed-loop system started in the 1960s but never got to a clinical practical stage of development. In recent years the availability of continuous glucose sensors revived those efforts and stimulated the clinician and researchers to believe that closing the loop might be possible nowadays. Many papers have been published over the years describing several different ideas on how to close the loop. Most of the suggested systems have a sensing arm that measures the blood glucose repeatedly or continuously, an insulin delivery arm that injects insulin upon command and a computer that makes the decisions of when and how much insulin to deliver. The differences between the various published systems in the literature are mainly in their control algorithms. However, there are also differences related to the method and site of glucose measurement and insulin delivery. SC glucose measurements and insulin delivery are the most studied option but other combinations of insulin measurements and glucose delivery including intravascular and intraperitoneal (IP) are explored. We tried to select recent publications that we believe had influenced and inspired people interested in the field.


Assuntos
Diabetes Mellitus/terapia , Sistemas de Infusão de Insulina , Pâncreas Artificial , Humanos , Bombas de Infusão Implantáveis
13.
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
14.
Recurso na Internet em Português | LIS - Localizador de Informação em Saúde | ID: lis-17868

RESUMO

Tradução adaptada do texto da resolução adotada pela 48ª Assembléia Geral da Associação Médica Mundial, realizada em Somerset West, República da África do Sul, em outubro de 1996. Trata da questão da violência familiar e apresenta a posição da entidade, recomendando a adoção de diretrizes pelas entidades nacionais.


Assuntos
Saúde Pública , 50230 , Violência Doméstica , Padrões de Prática Médica
15.
Int J Oncol ; 23(5): 1407-12, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14532983

RESUMO

Black cohosh is an increasingly popular alternative to estrogen replacement therapy for the relief of menopausal symptoms, primarily hot flushes. However, an important consideration for long-term therapy is potential toxicity and carcinogenicity. Therefore, we undertook a study to assess the estrogenic activity of black cohosh to examine its safety for those with, or at high risk of developing, breast cancer. Several assays were utilized as listed: RNAse protection assays, which ascertain the regulation of the expression of E2-responsive genes; estrogen-responsive-element (ERE)-luciferase, which determines modulation of the ER function by transactivation of the ERE; the Ishikawa cell system, which has an E2-regulated endogenous alkaline phosphatase; and colony formation of ER-expressing breast cancer cells, which indicates possible progression of early stage breast cancer into a more aggressive state. Black cohosh extracts did not demonstrate estrogenic activity in any of these assay systems. This is an encouraging step in the assessment of the safety of black cohosh for treatment of menopausal hot flushes.


Assuntos
Neoplasias da Mama/patologia , Cimicifuga/metabolismo , Estrogênios/metabolismo , Menopausa/efeitos dos fármacos , Extratos Vegetais , Fosfatase Alcalina/metabolismo , Neoplasias da Mama/tratamento farmacológico , Adesão Celular , Divisão Celular , Linhagem Celular Tumoral , Humanos , RNA Mensageiro/metabolismo , Receptores de Estrogênio/metabolismo , Ribonucleases/metabolismo
16.
J Environ Monit ; 5(1): 35-9, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12619754

RESUMO

Elevated carbon monoxide (CO) mixing ratios in excess of those derived from emissions inventories have been observed in plumes from one gas- and coal-fired power plant and three of four lignite coal-fired electric utility power plants observed in east and central Texas. Observations of elevated CO on days characterized by differing wind directions show that CO emissions from the lignite plants were relatively constant over time and cannot be ascribed to separate sources adjacent to the power plants. These three plants were found to be emitting CO at rates 22 to 34 times those tabulated in State and Federal emissions inventories. Elevated CO emissions from the gas- and coal-fired plant were highly variable on time scales of hours to days, in one case changing by a factor of 8 within an hour. Three other fossil-fueled power plants, including one lignite-fired plant observed during this study, did not emit substantial amounts of CO, suggesting that a combination of plant operating conditions and the use of lignite coal may contribute to the enhanced emissions. Observed elevated CO emissions from the three lignite plants, if representative of average operating conditions, represent an additional 30% of the annual total CO emissions from point sources for the state of Texas.


Assuntos
Poluentes Atmosféricos/análise , Monóxido de Carbono/análise , Combustíveis Fósseis , Centrais Elétricas , Carvão Mineral , Monitoramento Ambiental , Texas
17.
Artigo em Russo | MEDLINE | ID: mdl-12132220

RESUMO

Neuromapping, neuromyography, cerebrovascular mapping, cardiointervalography were conducted in children with the diagnosis "natal trauma of the cervical spine and vertebral arteries with ischemia of the reticular formation of the cerebral trunk in the form of myatonic syndrome". Adaptation reserves in the children were also studied. In addition to conventional methods, the treatment included kinesitherapy. The efficacy of the kinesitherapy was assessed.


Assuntos
Miotonia/reabilitação , Criança , Feminino , Humanos , Cinesiologia Aplicada , Masculino , Miotonia/fisiopatologia , Miotonia/terapia , Sistema Nervoso/fisiopatologia
18.
Oncogene ; 20(48): 7110-4, 2001 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-11704836

RESUMO

Transcriptional regulation of the BRCA1 proximal promoter has been suggested to play a role in the decreased expression of BRCA1 observed in sporadic breast cancer. Computer analysis of the sequence of the proximal promoter reveals the presence of a potential CREB site. We have identified CREB/ATF-1 as the factor interacting with this site in nuclear extracts from MCF-7 and T-47D cells. This site is shown to be important for the constitutive expression of the promoter in these cells, as well as in Hep G2 cells. Despite the presence of this site, the BRCA1 promoter is not responsive to cAMP induction. It appears that CREB acts as a constitutive positive element for BRCA1 expression and that any mechanism inactivating CREB function would have a dramatic effect on BRCA1 expression.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas de Ligação a DNA , Regulação Neoplásica da Expressão Gênica/genética , Genes BRCA1 , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica/genética , Fator 1 Ativador da Transcrição , Adenocarcinoma/genética , Adenocarcinoma/patologia , Sequência de Bases , Sítios de Ligação , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Colforsina/farmacologia , Ilhas de CpG , AMP Cíclico/farmacologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/química , Metilação de DNA , DNA de Neoplasias/genética , Dimerização , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica , Fatores de Transcrição/química , Transfecção , Células Tumorais Cultivadas/efeitos dos fármacos
19.
Science ; 292(5517): 719-23, 2001 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-11326097

RESUMO

Data taken in aircraft transects of emissions plumes from rural U.S. coal-fired power plants were used to confirm and quantify the nonlinear dependence of tropospheric ozone formation on plume NO(x) (NO plus NO(2)) concentration, which is determined by plant NO(x) emission rate and atmospheric dispersion. The ambient availability of reactive volatile organic compounds, principally biogenic isoprene, was also found to modulate ozone production rate and yield in these rural plumes. Differences of a factor of 2 or greater in plume ozone formation rates and yields as a function of NO(x) and volatile organic compound concentrations were consistently observed. These large differences suggest that consideration of power plant NO(x) emission rates and geographic locations in current and future U.S. ozone control strategies could substantially enhance the efficacy of NO(x) reductions from these sources.

20.
Science ; 291(5506): 1026-31, 2001 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-11161213

RESUMO

Large particles containing nitric acid (HNO3) were observed in the 1999/2000 Arctic winter stratosphere. These in situ observations were made over a large altitude range (16 to 21 kilometers) and horizontal extent (1800 kilometers) on several airborne sampling flights during a period of several weeks. With diameters of 10 to 20 micrometers, these sedimenting particles have significant potential to denitrify the lower stratosphere. A microphysical model of nitric acid trihydrate particles is able to simulate the growth and sedimentation of these large sizes in the lower stratosphere, but the nucleation process is not yet known. Accurate modeling of the formation of these large particles is essential for understanding Arctic denitrification and predicting future Arctic ozone abundances.

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