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1.
J Biol Chem ; 298(11): 102563, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36209820

RESUMO

RNA-binding proteins of the DBHS (Drosophila Behavior Human Splicing) family, NONO, SFPQ, and PSPC1 have numerous roles in genome stability and transcriptional and posttranscriptional regulation. Critical to DBHS activity is their recruitment to distinct subnuclear locations, for example, paraspeckle condensates, where DBHS proteins bind to the long noncoding RNA NEAT1 in the first essential step in paraspeckle formation. To carry out their diverse roles, DBHS proteins form homodimers and heterodimers, but how this dimerization influences DBHS localization and function is unknown. Here, we present an inducible GFP-NONO stable cell line and use it for live-cell 3D-structured illumination microscopy, revealing paraspeckles with dynamic, twisted elongated structures. Using siRNA knockdowns, we show these labeled paraspeckles consist of GFP-NONO/endogenous SFPQ dimers and that GFP-NONO localization to paraspeckles depends on endogenous SFPQ. Using purified proteins, we confirm that partner swapping between NONO and SFPQ occurs readily in vitro. Crystallographic analysis of the NONO-SFPQ heterodimer reveals conformational differences to the other DBHS dimer structures, which may contribute to partner preference, RNA specificity, and subnuclear localization. Thus overall, our study suggests heterodimer partner availability is crucial for NONO subnuclear distribution and helps explain the complexity of both DBHS protein and paraspeckle dynamics through imaging and structural approaches.


Assuntos
Paraspeckles , RNA Longo não Codificante , Humanos , Dimerização , Proteínas de Ligação a RNA/metabolismo , Regulação da Expressão Gênica , RNA Longo não Codificante/genética
2.
Int J Mol Sci ; 22(21)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34768837

RESUMO

Acute kidney injury (AKI) causes a lot of harm to human health but is treated by only supportive therapy in most cases. Recent evidence shows that mesenchymal stem cells (MSCs) benefit kidney regeneration through releasing paracrine factors and extracellular vesicles (EVs) to the recipient kidney cells and are considered to be promising cellular therapy for AKI. To develop more efficient, precise therapies for AKI, we review the therapeutic mechanism of MSCs and MSC-derived EVs in AKI and look for a better understanding of molecular signaling and cellular communication between donor MSCs and recipient kidney cells. We also review recent clinical trials of MSC-EVs in AKI. This review summarizes the molecular mechanisms of MSCs' therapeutic effects on kidney regeneration, expecting to comprehensively facilitate future clinical application for treating AKI.


Assuntos
Injúria Renal Aguda/terapia , Vesículas Extracelulares/transplante , Células-Tronco Mesenquimais/metabolismo , Injúria Renal Aguda/metabolismo , Animais , Terapia Baseada em Transplante de Células e Tecidos/métodos , Vesículas Extracelulares/fisiologia , Regeneração Tecidual Guiada/métodos , Humanos , Rim/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/fisiologia , Regeneração
3.
Mar Pollut Bull ; 136: 114-124, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30509792

RESUMO

The environmental impact caused by thermal discharge waters of power plants is of global concern since thermal discharge directly affects the environmental situation near power plants. The present study used the vital stain neutral red to identify live and dead zooplankton collected from stations at the intake and the outlet of two nuclear power plants (NPPs). Significantly higher mortalities occurred at the outlet station than at the intake station (p < 0.01) at both NPPs. The mortalities of most zooplankton taxa and all zooplankton assemblages were significantly positive correlated to differences of water temperature (ΔT) at NPP I (p < 0.05), whereas it was not significantly positive correlated with ΔT at NPP II (p > 0.05). The weight of organic matter of zooplankton fragments was higher at the outlet station than at the intake station at both NPPs, indicating the physical damage of zooplankton when passing the cooling system.


Assuntos
Monitoramento Ambiental/métodos , Centrais Nucleares , Poluição da Água , Zooplâncton/crescimento & desenvolvimento , Animais , Peso Corporal , Vermelho Neutro , Coloração e Rotulagem , Taiwan , Temperatura , Poluição da Água/efeitos adversos , Poluição da Água/análise
4.
J Phys Chem A ; 119(28): 7293-304, 2015 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-25658197

RESUMO

Following photodissociation of gaseous acryloyl chloride, CH2CHC(O)Cl, at 193 nm, temporally resolved vibration-rotational emission spectra of HCl (v ≤ 7, J ≤ 35) in region 2350-3250 cm(-1) and of CO (v ≤ 4, J ≤ 67) in region 1865-2300 cm(-1) were recorded with a step-scan Fourier-transform spectrometer. The HCl emission shows a minor low-J component for v ≤ 4 with average rotational energy Erot = 9 ± 3 kJ mol(-1) and vibrational energy Evib = 28 ± 7 kJ mol(-1) and a major high-J component for v ≤ 7 with average rotational energy Erot = 36 ± 6 kJ mol(-1) and vibrational energy Evib = 49 ± 9 kJ mol(-1); the branching ratio of these two channels is ∼0.2:0.8. Using electronic structure calculations to characterize the transition states and each intrinsic reaction coordinate, we find that the minor pathway corresponds to the four-center HCl-elimination of CH2ClCHCO following a 1,3-Cl-shift of CH2CHC(O)Cl, whereas the major pathway corresponds to the direct four-center HCl-elimination of CH2CHC(O)Cl. Although several channels are expected for CO produced from the secondary dissociation of C2H3CO and H2C═C═C═O, each produced from two possible dissociation channels of CH2CHC(O)Cl, the CO emission shows a near-Boltzmann rotational distribution with average rotational energy Erot = 21 ± 4 kJ mol(-1) and average vibrational energy Evib = 10 ± 4 kJ mol(-1). Consideration of the branching fractions suggests that the CO observed with greater vibrational excitation might result from secondary decomposition of H2C═C═C═O that was produced via the minor low-J HCl-elimination channel, while the internal state distributions of CO produced from the other three channels are indistinguishable. We also introduce a method for choosing the correct point along the intrinsic reaction coordinate for a roaming HCl elimination channel to generate a Franck-Condon prediction for the HCl vibrational energy.

5.
J Nephrol ; 26(4): 755-62, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23042434

RESUMO

BACKGROUND: Polycystic kidney disease (PCKD) is one of the most common inherited disorders in end-stage renal disease patients. It is generally thought that the survival of PCKD patients undergoing dialysis surpasses that of general dialysis patients, but the cause of this improved survival is not clear. METHODS: Using Taiwan's national health insurance claims data, we performed a longitudinal cohort study to investigate the survival and impact of comorbidities on mortality in dialysis patients with and without PCKD. We excluded patients without diabetes mellitus (DM) in a further analysis. A Cox proportional hazards model was used to identify the risk factors for all-cause mortality. The Kaplan-Meier method was used to describe overall patient survival. RESULTS: Five hundred and one (2.25%) of 22,298 nondiabetic incident dialysis patients had PCKD. We found no significant difference in survival rates between those with and without PCKD. Being male, being over 65 years old and having congestive heart failure or cerebrovascular accident were each found to be independent predictors of mortality in the PCKD dialysis patients. CONCLUSIONS: Taiwan has a lower incidence rate of PCKD than Western countries. In Taiwan, there is little difference in the long-term survival between dialysis patients with and without PCKD.


Assuntos
Falência Renal Crônica/mortalidade , Doenças Renais Policísticas/mortalidade , Diálise Renal/mortalidade , Feminino , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Doenças Renais Policísticas/complicações , Doenças Renais Policísticas/epidemiologia , Taiwan/epidemiologia
6.
Malar J ; 11: 408, 2012 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-23217163

RESUMO

BACKGROUND: A reliable and simple test for the detection of malaria parasite is crucial in providing effective treatment and therapeutic follow-up, especially in malaria elimination programmes. A comparison of four methods, including nested polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) were used for the malaria diagnosis and treatment follow-up in São Tomé and Príncipe, during a successful pre-elimination campaign. METHOD: During the period September to November 2009, blood samples from 128 children (five to 14 years old) with temperature ≥38°C (tympanic) in the District of Agua Grande were examined using four different methods, i.e., histidine-rich protein 2 (HRP-2) based rapid diagnostic tests (HRP-2-RDTs), optical microscopy, nested PCR, and LAMP. First-line treatment with artesunate-amodiaquine was given for uncomplicated malaria and intravenous quinine was given for complicated malaria. Children with persistent positivity for malaria by microscopy, or either by nested PCR, or by LAMP on day 7 were given second-line treatment with artemether-lumefantrine. Treatment follow-up was made weekly, for up to four weeks. RESULTS: On day 0, positive results for HRP-2-RDTs, microscopy, nested PCR, and LAMP, were 68(53%), 47(37%), 64(50%), and 65(51%), respectively. When nested PCR was used as a reference standard, only LAMP was comparable; both HRP-2-RDTs and microscopy had moderate sensitivity; HRP-2-RDTs had poor positive predictive value (PPV) and a moderate negative predictive value (NPV) for the treatment follow-up. Seventy-one children with uncomplicated malaria and eight children with complicated falciparum malaria were diagnosed based on at least one positive result from the four tests as well as clinical criteria. Twelve of the 79 children receiving first-line treatment had positive results by nested PCR on day 7 (nested PCR-corrected day 7 cure rate was 85%). After the second-line treatment, nested PCR/LAMP-corrected day 28 cure rate was 83% for these 12 children. CONCLUSIONS: HRP-2-RDTs have similar sensitivity as microscopy but less specificity. However, as compared to nested PCR, the poor sensitivity of HRP-2-RDTs indicates that low parasitaemia may not be detected after treatment, as well as the low specificity of HRP-2-RDTs indicates it cannot be applied for treatment follow-up. LAMP has similar sensitivity and specificity to nested PCR. With high PPV and NPV, LAMP is simpler and faster as compared to nested PCR with the advantage of detecting low parasitaemia becoming a potential point-of-care test for treatment follow-up.


Assuntos
Monitoramento de Medicamentos/métodos , Malária/diagnóstico , Malária/tratamento farmacológico , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Adolescente , Antimaláricos/administração & dosagem , Ilhas Atlânticas , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Sensibilidade e Especificidade
7.
PLoS One ; 7(7): e40633, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22844405

RESUMO

AIMS: The main focus of this study is to illustrate the importance of the statistical analysis in the evaluation of the accuracy of malaria diagnostic tests, without admitting a reference test, exploring a dataset (n=3317) collected in São Tomé and Príncipe. METHODS: Bayesian Latent Class Models (without and with constraints) are used to estimate the malaria infection prevalence, together with sensitivities, specificities, and predictive values of three diagnostic tests (RDT, Microscopy and PCR), in four subpopulations simultaneously based on a stratified analysis by age groups (< 5, ≥ 5 years old) and fever status (febrile, afebrile). RESULTS: In the afebrile individuals with at least five years old, the posterior mean of the malaria infection prevalence is 3.2% with a highest posterior density interval of [2.3-4.1]. The other three subpopulations (febrile ≥ 5 years, afebrile or febrile children less than 5 years) present a higher prevalence around 10.3% [8.8-11.7]. In afebrile children under-five years old, the sensitivity of microscopy is 50.5% [37.7-63.2]. In children under-five, the estimated sensitivities/specificities of RDT are 95.4% [90.3-99.5]/93.8% [91.6-96.0]--afebrile--and 94.1% [87.5-99.4]/97.5% [95.5-99.3]--febrile. In individuals with at least five years old are 96.0% [91.5-99.7]/98.7% [98.1-99.2]--afebrile--and 97.9% [95.3-99.8]/97.7% [96.6-98.6]--febrile. The PCR yields the most reliable results in four subpopulations. CONCLUSIONS: The utility of this RDT in the field seems to be relevant. However, in all subpopulations, data provide enough evidence to suggest caution with the positive predictive values of the RDT. Microscopy has poor sensitivity compared to the other tests, particularly, in the afebrile children less than 5 years. This type of findings reveals the danger of statistical analysis based on microscopy as a reference test. Bayesian Latent Class Models provide a powerful tool to evaluate malaria diagnostic tests, taking into account different groups of interest.


Assuntos
Malária/diagnóstico , Modelos Estatísticos , Teorema de Bayes , Criança , Pré-Escolar , Humanos , Malária/epidemiologia , Valor Preditivo dos Testes
8.
Malar J ; 9: 264, 2010 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-20920216

RESUMO

BACKGROUND: Plasmodium falciparum is the major cause of malaria infection in the island of São Tomé, in the Republic of São Tomé and Príncipe (STP), with an incidence of 40 - 50% before 2004. Since 2004, through the coordination of the Ministry of Health of STP and their Centro Nacional de Endemias (CNE), an integrated malaria control programme has been intensively deployed on the island of São Tomé. Malaria morbidity and mortality decreased by 95% after three years of effective intervention. In the low transmission settings, however, malaria seasonal fluctuation can be a potential problem directly related to epidemics if ongoing control measures are interrupted. Studies on a number of associated factors with malaria epidemics and the measures taken to respond to outbreaks are presented. METHODS: The integrated malaria control programme included indoor residual spraying (IRS), long-lasting insecticidal nets (LLINs), intermittent preventive therapy for pregnant women, as well as early diagnosis and prompt treatment with artemisinin-based combination therapy (ACT). Regular implementation of an island-wide IRS programme was carried out yearly in 2004-2007, and enhanced throughout the island in 2009. Malaria incidence and prevalence were estimated based on passive case detection and mass screening, respectively. Slide positivity rates were used for monitoring the beginning of a malaria epidemic or a seasonal peak. RESULTS: A steep decline of ca. 95% of malaria morbidity and mortality was observed between 2004 and 2008 with use of the combined control methods. Malaria incidence was 2.0%, 1.5%, and 3.0% for 2007, 2008, and 2009, respectively. In April 2008, a cross-sectional country-wide surveillance showed malaria prevalence of 3.5%, of which 95% cases were asymptomatic carriers. Only 50% of asymptomatic carriers were cured with ACT treatment, while 90% of the symptomatic patients were cured by ACT treatment as confirmed with a follow up study. Malaria morbidity increased by three-fold during the first half of 2009 as compared to the same period in 2008. Over this period of six months, severe malaria was also noted in all age groups and malaria mortality increased by two-fold in children less than five years old. After an emergency IRS was deployed, with increased use of LLINs, and an active search of asymptomatic carriers was followed and given complete ACT treatment, malaria incidence decreased to less than 1% in the second half of 2009. CONCLUSION: At the initial stage of the integrated malaria control programme, IRS contributed to the visible effect on the rapid reduction of malaria morbidity and mortality, while this programme highlights an urgent demand for the improvement of other measures, particularly promotion of LLINs usage, with close monitoring of asymptomatic carriers and with ACT treatment in malaria transmission hotspots. In addition, both daily reports and a regular active surveillance to prevent malaria outbreaks should be established permanently, so that a fast response to epidemics can be effectively made when necessary.


Assuntos
Malária/epidemiologia , Malária/prevenção & controle , Plasmodium/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Ilhas Atlânticas/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Mosquiteiros Tratados com Inseticida , Lactonas/uso terapêutico , Masculino , Microscopia/métodos , Pessoa de Meia-Idade , Controle de Mosquitos/métodos , Parasitologia/métodos , Gravidez , Estações do Ano , Adulto Jovem
9.
Malar J ; 9: 26, 2010 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-20089158

RESUMO

BACKGROUND: Plasmodium falciparum is the major species responsible for malaria transmission on the island of Príncipe, in the Republic of São Tomé and Príncipe (STP). Indoor residual spraying (IRS) has been intensively deployed on the island, since 2003. Other measures included intermittent preventive therapy (IPT), since 2004, as well as artemisinin-based therapy (ACT) and long-lasting insecticidal nets (LLINs) from 2005. The work was coordinated by the Ministry of Health of STP through their Centro Nacional de Endemias (CNE) and the impact of such an integrated control programme on the prevalence and epidemiology of malaria in Príncipe was evaluated. METHODS: The scaling-up of preventive strategies included IRS, LLINs, IPT for pregnant women, as well as early diagnosis and prompt treatment with ACT. Regular implementation of an island-wide IRS programme was carried out yearly in 2003-2005, and later in 2008. Malaria incidence and prevalence were estimated based on passive case detection and active case detection, respectively. Slide positivity rate (SPR) was used as an indicator of any increase of malaria cases during and after the control programme was initiated. RESULTS: Regular IRS achieved a coverage of 85-90% for each of the four annual cycles (2003-2005, annually and one spraying in 2008) while usage of LLINs was never superior to 50% from 2006-2009. Coverage of IPT steadily increased from 50% in 2004 to 80% in 2008. Since 2006, over 90% of uncomplicated malaria patients received ACT treatment. Severe malaria cases were hospitalized and treated with quinine. Monthly trends of SPR were constantly over 50% in 2003, but steadily decreased below 10% in 2006. SPR has been below 5% since 2007, but an increase to up to 15% was noted in June 2009 when 16 imported cases were detected. A steep decline by 99% of malaria incidence was observed between 2003 and 2008, with an incidence risk of the population of five per thousand, in 2008. No malaria mortality has been reported since 2005. Species shift from falciparum to non-falciparum malaria was noted after a five-year intensive control programme. Cross-sectional country-wide active surveillances showed malaria prevalences of 1.1%, 0.7%, and 0.9% in June 2006, Oct 2007, and July 2009, respectively, of which over 90% were asymptomatic. CONCLUSION: The effective measures of the combination of four major control methods have produced a rapid decline in malaria morbidity and mortality on the island of Príncipe. The combination of IRS, IPT, and active surveillance with ACT treatment seemed to have played important roles to achieve a present status of low and stable malaria on the island. In low transmission settings, any increase of malaria morbidity indicates potential epidemics and assumes that current control strategies were interrupted. Active surveillance should be reinforced to follow and monitor all asymptomatic carriers and imported cases. Consolidation and a shift to elimination phase demands the sustainability of such integrated programmes.


Assuntos
Antimaláricos/uso terapêutico , Insetos Vetores/parasitologia , Malária Falciparum/prevenção & controle , Controle de Mosquitos/métodos , Animais , Ilhas Atlânticas/epidemiologia , Roupas de Cama, Mesa e Banho/estatística & dados numéricos , Estudos Transversais , Quimioterapia Combinada , Feminino , Humanos , Incidência , Inseticidas , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Masculino , Parasitemia/tratamento farmacológico , Parasitemia/epidemiologia , Parasitemia/parasitologia , Plasmodium falciparum/isolamento & purificação , Gravidez , Complicações na Gravidez/parasitologia , Prevalência , Inquéritos e Questionários
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