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1.
Phys Chem Chem Phys ; 23(2): 1500-1509, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33400746

RESUMO

The aggregation of coronene is relevant to understand the formation of carbon nanomaterials, including graphene quantum dots (GQDs) that show exceptional photophysical properties. This article evaluates the influence of carboxyl and amine substituting groups on the aggregation of coronene by performing a global optimization study based on a new potential energy surface. The structures of clusters with substituted coronene are similar to those formed by un-substituted monomers, that is, stacked (non-stacked) motifs are favoured for small-size (large-size) clusters. Nonetheless, the presence of carboxyl and amine groups leads to an increase of the number of local minima of comparable energy. The clusters with substituted monomers have also shown to enhance the attractive component interaction, which can be attributed to weak induction and charge transfer effects and to stronger electrostatic contributions. Moreover, the calculated height of magic-number structures of the clusters in this work is compatible with the morphology of the GQDs reported in the literature.

2.
Mol Biol Rep ; 47(11): 8757-8762, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33085049

RESUMO

Patients with HIV-AIDS treated with antiretroviral drugs still have high prevalence of cognitive disorders and many factors are likely to contribute for ongoing neurologic decline such as chronic low-level infection, coinfections with hepatitis B and C and genetic influences, both the virus and the host. Some evidences suggest that the genetic APOE polymorphism may be an associated risk factor. This study aimed to evaluate the association between APOE polymorphisms and cognitive disorders in patients with HIV-AIDS. This was a cross-sectional study comprising 133 patients aged 19-59 years old, with HIV-AIDS and were assisted at the infectious disease outpatient clinics at Hospital Universitário Oswaldo Cruz, in Recife, Brazil. For cognitive evaluation, Mini-Mental State Examination test (MMSE) and Montreal Cognitive Assessment test (MoCA) were used. The determination of APOE gene polymorphism was performed by using the PCR-RFLP technique. Sociodemographic and clinical characteristics were not significantly associated to APOE ε4 polymorphism, except for the high results of CD4 rate (p < 0.015). There was an absence associated between APOE ε4 polymorphism and neurocognitive tests. This study found no association between cognitive alterations and APOE polymorphism in patients with HIV-AIDS in the Northeast of Brazil. The imbalance of APOE allelic frequency distribution, according to Hardy-Weinberg law, there could be an adjustment phase of its equilibrium suffered by the HIV virus, however, the mechanism is still unknown.


Assuntos
Síndrome da Imunodeficiência Adquirida/patologia , Apolipoproteínas E/genética , Transtornos Cognitivos , Infecções por HIV/patologia , Síndrome da Imunodeficiência Adquirida/genética , Adulto , Brasil , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/genética , Estudos Transversais , Feminino , Infecções por HIV/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Adulto Jovem
3.
Nature ; 506(7486): 76-80, 2014 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-24499918

RESUMO

Feedbacks between land carbon pools and climate provide one of the largest sources of uncertainty in our predictions of global climate. Estimates of the sensitivity of the terrestrial carbon budget to climate anomalies in the tropics and the identification of the mechanisms responsible for feedback effects remain uncertain. The Amazon basin stores a vast amount of carbon, and has experienced increasingly higher temperatures and more frequent floods and droughts over the past two decades. Here we report seasonal and annual carbon balances across the Amazon basin, based on carbon dioxide and carbon monoxide measurements for the anomalously dry and wet years 2010 and 2011, respectively. We find that the Amazon basin lost 0.48 ± 0.18 petagrams of carbon per year (Pg C yr(-1)) during the dry year but was carbon neutral (0.06 ± 0.1 Pg C yr(-1)) during the wet year. Taking into account carbon losses from fire by using carbon monoxide measurements, we derived the basin net biome exchange (that is, the carbon flux between the non-burned forest and the atmosphere) revealing that during the dry year, vegetation was carbon neutral. During the wet year, vegetation was a net carbon sink of 0.25 ± 0.14 Pg C yr(-1), which is roughly consistent with the mean long-term intact-forest biomass sink of 0.39 ± 0.10 Pg C yr(-1) previously estimated from forest censuses. Observations from Amazonian forest plots suggest the suppression of photosynthesis during drought as the primary cause for the 2010 sink neutralization. Overall, our results suggest that moisture has an important role in determining the Amazonian carbon balance. If the recent trend of increasing precipitation extremes persists, the Amazon may become an increasing carbon source as a result of both emissions from fires and the suppression of net biome exchange by drought.


Assuntos
Atmosfera/química , Ciclo do Carbono , Secas/estatística & dados numéricos , Biomassa , Biota , Brasil , Dióxido de Carbono/análise , Monóxido de Carbono/análise , Incêndios/estatística & dados numéricos , Água Doce/análise , Fotossíntese , Chuva , Estações do Ano , Árvores/metabolismo , Clima Tropical
4.
Lupus ; 28(12): 1441-1451, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31594456

RESUMO

OBJECTIVE: Lupus is a chronic, autoimmune disease that disproportionately affects African Americans. We adapted the Centers for Disease Control and Prevention's Popular Opinion Leader model to implement an intervention tailored for African American individuals that leverages an academic-community partnership and community-based social networks to disseminate culturally appropriate lupus education. METHODS: Academic rheumatologists, social scientists, and researchers in Boston, MA and Chicago, IL partnered with local lupus support groups, community organizations, and churches in neighborhoods with higher proportions of African Americans to develop curriculum and recruit community leaders with and without lupus (Popular Opinion Leaders; POLs). POLs attended four training sessions focused on lupus education, strategies to educate others, and a review of research methods. POLs disseminated information through their social networks and recorded their impact, which was mapped using a geographic information system framework. RESULTS: We trained 18 POLs in greater Boston and 19 in greater Chicago: 97% were African American, 97% were female; and the mean age was 57 years. Fifty-nine percent of Boston POLs and 68% of Chicago POLs had lupus. POLs at both sites engaged members of their social networks and communities in conversations about lupus, health disparities, and the importance of care. Boston POLs documented 97 encounters with 547 community members reached. Chicago POLs documented 124 encounters with 4083 community members reached. CONCLUSIONS: An adapted, community-based POL model can be used to disseminate lupus education and increase awareness in African American communities. Further research is needed to determine the degree to which this may begin to reduce disparities in access to care and outcomes.


Assuntos
Conscientização , Negro ou Afro-Americano/educação , Redes Comunitárias/organização & administração , Lúpus Eritematoso Sistêmico/epidemiologia , Adulto , Negro ou Afro-Americano/psicologia , Idoso , Centers for Disease Control and Prevention, U.S./organização & administração , Doença Crônica , Redes Comunitárias/tendências , Feminino , Sistemas de Informação Geográfica/instrumentação , Promoção da Saúde/métodos , Disparidades em Assistência à Saúde/etnologia , Disparidades em Assistência à Saúde/estatística & dados numéricos , Humanos , Disseminação de Informação/métodos , Liderança , Lúpus Eritematoso Sistêmico/prevenção & controle , Masculino , Pessoa de Meia-Idade , Opinião Pública , Projetos de Pesquisa , Estados Unidos/etnologia
12.
Scand J Immunol ; 86(1): 40-49, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28426172

RESUMO

It is well established that helper T cell responses influence resistance or susceptibility to Mycobacterium leprae infection, but the role of more recently described helper T cell subsets in determining severity is less clear. To investigate the involvement of Th17 cells in the pathogenesis of leprosy, we determined the immune profile with variant presentations of leprosy. Firstly, IL-17A, IFN-γ and IL-10 were evaluated in conjunction with CD4+ T cell staining by confocal microscopy of lesion biopsies from tuberculoid (TT) and lepromatous leprosy (LL) patients. Secondly, inflammatory cytokines were measured by multiplex assay of serum samples from Multibacillary (MB, n = 28) and Paucibacillary (PB, n = 23) patients and household contacts (HHC, n = 23). Patients with leprosy were also evaluated for leprosy reaction occurrence: LR+ (n = 8) and LR- (n = 20). Finally, peripheral blood mononuclear cells were analysed by flow cytometry used to determine the phenotype of cytokine-producing cells. Lesions from TT patients were found to have more CD4+ IL-17A+ cells than those from LL patients. Higher concentrations of IL-17A and IL-1ß were observed in serum from PB than MB patients. The highest serum IFN-γ concentrations were, however, detected in sera from MB patients that developed leprosy reactions (MB LR+ ). Together, these results indicate that Th1 cells were associated with both the PB presentation and also with leprosy reactions. In contrast, Th17 cells were associated with an effective inflammatory response that is present in the PB forms but were not predictive of leprosy reactions in MB patients.


Assuntos
Mediadores da Inflamação/imunologia , Hanseníase Paucibacilar/imunologia , Hanseníase/imunologia , Mycobacterium leprae/imunologia , Células Th1/imunologia , Células Th17/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Criança , Busca de Comunicante , Feminino , Citometria de Fluxo , Humanos , Mediadores da Inflamação/sangue , Mediadores da Inflamação/metabolismo , Interferon gama/sangue , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-10/sangue , Interleucina-10/imunologia , Interleucina-10/metabolismo , Interleucina-17/sangue , Interleucina-17/imunologia , Interleucina-17/metabolismo , Interleucina-1beta/sangue , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Hanseníase/sangue , Hanseníase/microbiologia , Hanseníase Multibacilar/sangue , Hanseníase Multibacilar/imunologia , Hanseníase Multibacilar/microbiologia , Hanseníase Paucibacilar/sangue , Hanseníase Paucibacilar/microbiologia , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Mycobacterium leprae/fisiologia , Células Th1/metabolismo , Células Th17/metabolismo , Adulto Jovem
15.
J Anim Physiol Anim Nutr (Berl) ; 101(6): 1215-1226, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28133820

RESUMO

The aim of this study was to assess the nutritional effect of tomato pomace, in combination with two distinct fat sources (lard or soya bean oil), on longissimus lumborum muscle, subcutaneous fat and liver of young pigs. Forty male pigs of 4 weeks old were randomly assigned to four dietary treatments using two fibre sources (wheat bran or 5.0% tomato pomace) and two fat sources (lard or soya bean oil), in a 2 × 2 factorial design for a 5-week trial. Tomato pomace did not improve colour, fatty acid profile, cholesterol content or lipid oxidation, nor did it yield detectable levels in lycopene or ß-carotene in the meat (p > 0.05). However, a positive increase in α-tocopherol content of meat and liver was observed in pigs fed tomato pomace (p < 0.05). Compared with lard, soya bean oil increased MUFA and PUFA proportions and decreased the percentage of SFA (p < 0.05). Our results indicate that 5.0% of tomato pomace increases pork oxidative stability and that 5.0% of soya bean oil, compared with lard, improves its nutritional quality.


Assuntos
Ração Animal/análise , Dieta/veterinária , Carne/análise , Solanum lycopersicum , Fenômenos Fisiológicos da Nutrição Animal , Animais , Ácidos Graxos/química , Peroxidação de Lipídeos , Oxirredução , Suínos/fisiologia
17.
J Opt Soc Am A Opt Image Sci Vis ; 31(1): 101-13, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24561945

RESUMO

Multi-object adaptive optics (MOAO) systems are still in their infancy: their complex optical designs for tomographic, wide-field wavefront sensing, coupled with open-loop (OL) correction, make their calibration a challenge. The correction of a discrete number of specific directions in the field allows for streamlined application of a general class of spatio-angular algorithms, initially proposed in Whiteley et al. [J. Opt. Soc. Am. A15, 2097 (1998)], which is compatible with partial on-line calibration. The recent Learn & Apply algorithm from Vidal et al. [J. Opt. Soc. Am. A27, A253 (2010)] can then be reinterpreted in a broader framework of tomographic algorithms and is shown to be a special case that exploits the particulars of OL and aperture-plane phase conjugation. An extension to embed a temporal prediction step to tackle sky-coverage limitations is discussed. The trade-off between lengthening the camera integration period, therefore increasing system lag error, and the resulting improvement in SNR can be shifted to higher guide-star magnitudes by introducing temporal prediction. The derivation of the optimal predictor and a comparison to suboptimal autoregressive models is provided using temporal structure functions. It is shown using end-to-end simulations of Raven, the MOAO science, and technology demonstrator for the 8 m Subaru telescope that prediction allows by itself the use of 1-magnitude-fainter guide stars.

18.
Anaesthesia ; 69(1): 72-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24224548

RESUMO

We describe the management of a 62-year-old man who developed severe pain, cramps, paraplegia and pulmonary oedema after the accidental administration of potassium chloride into the subarachnoid space. In addition to supportive treatment, we performed cerebrospinal fluid lavage with saline 0.9%. The patient recovered well without any permanent injury.


Assuntos
Raquianestesia/efeitos adversos , Erros de Medicação/efeitos adversos , Cloreto de Potássio/intoxicação , Irrigação Terapêutica/métodos , Anestésicos Locais , Bupivacaína , Embalagem de Medicamentos , Humanos , Injeções Espinhais , Masculino , Pessoa de Meia-Idade , Paraplegia/induzido quimicamente , Paraplegia/terapia
19.
Mar Pollut Bull ; 174: 113296, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34995889

RESUMO

This study aimed to assess the influence of treated wastewater disposal on Ria Formosa coastal lagoon (South Portugal), the largest national producer of bivalve mollusks. Water quality was evaluated at two areas under different wastewater loads and hydrodynamic conditions, using physico-chemical variables, bacterial indicators of contamination, chlorophyll-a concentration, phytoplankton abundance and composition. Samples were collected monthly, between October 2018 and September 2019. Minor influence of effluent discharge was detected at the eastern Olhão area, exposed to stronger hydrodynamics and higher wastewater load than the northwestern Faro area (ca. 2-4-fold total nitrogen and phosphorus). The lower load weakly flushed area showed a poorer water quality, up to 500 m from the discharge point, more marked during the spring-summer period. The intensity, persistence, and spatial extent of the wastewater footprint, lower for the highest-loading area, reflected the role of local hydrodynamic conditions, modulating the influence of wastewater discharge on lagoonal water quality.


Assuntos
Águas Residuárias , Qualidade da Água , Monitoramento Ambiental , Hidrodinâmica , Portugal , Taiwan
20.
Rev Esp Anestesiol Reanim (Engl Ed) ; 69(2): 102-104, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35168918

RESUMO

INTRODUCTION: The development of a subcutaneous implantable cardioverter-defibrillator (S-ICD) combined with the typical patient comorbidities creates new challenges for anaesthesia. CLINICAL CASE: A young male, ASA II, was proposed for S-ICD placement, after recovery from a sudden CRP episode. We performed regional anaesthesia with a serratus plane block (SPB) and transversus thoracic muscle plane block (TTPB) with administration of Mepivacaine and Ropivacaine. S-ICD placement was achieved under regional anaesthesia. In the perioperative period, the patient remained hemodynamically stable, without any complications or pain. DISCUSSION: The implantation of the ICD occurs in fragile patients, with high anaesthetic risk. In this case, the association of SPB and TTPB was an effective anaesthetic/analgesic approach, has advantages when compared with other techniques and has potential use in other procedures.


Assuntos
Anestesia por Condução , Bloqueio Nervoso , Humanos , Masculino , Músculo Esquelético , Bloqueio Nervoso/métodos , Tela Subcutânea
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