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1.
Proc Natl Acad Sci U S A ; 120(32): e2216141120, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37523525

RESUMO

Living longer without simultaneously extending years spent in good health ("health span") is an increasing societal burden, demanding new therapeutic strategies. Hydrogen sulfide (H2S) can correct disease-related mitochondrial metabolic deficiencies, and supraphysiological H2S concentrations can pro health span. However, the efficacy and mechanisms of mitochondrion-targeted sulfide delivery molecules (mtH2S) administered across the adult life course are unknown. Using a Caenorhabditis elegans aging model, we compared untargeted H2S (NaGYY4137, 100 µM and 100 nM) and mtH2S (AP39, 100 nM) donor effects on life span, neuromuscular health span, and mitochondrial integrity. H2S donors were administered from birth or in young/middle-aged animals (day 0, 2, or 4 postadulthood). RNAi pharmacogenetic interventions and transcriptomics/network analysis explored molecular events governing mtH2S donor-mediated health span. Developmentally administered mtH2S (100 nM) improved life/health span vs. equivalent untargeted H2S doses. mtH2S preserved aging mitochondrial structure, content (citrate synthase activity) and neuromuscular strength. Knockdown of H2S metabolism enzymes and FoxO/daf-16 prevented the positive health span effects of mtH2S, whereas DCAF11/wdr-23 - Nrf2/skn-1 oxidative stress protection pathways were dispensable. Health span, but not life span, increased with all adult-onset mtH2S treatments. Adult mtH2S treatment also rejuvenated aging transcriptomes by minimizing expression declines of mitochondria and cytoskeletal components, and peroxisome metabolism hub components, under mechanistic control by the elt-6/elt-3 transcription factor circuit. H2S health span extension likely acts at the mitochondrial level, the mechanisms of which dissociate from life span across adult vs. developmental treatment timings. The small mtH2S doses required for health span extension, combined with efficacy in adult animals, suggest mtH2S is a potential healthy aging therapeutic.


Assuntos
Proteínas de Caenorhabditis elegans , Sulfeto de Hidrogênio , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Longevidade , Sulfetos/metabolismo , Sulfeto de Hidrogênio/metabolismo , Mitocôndrias/metabolismo , Estresse Oxidativo , Fatores de Transcrição GATA/metabolismo
2.
Respir Res ; 25(1): 49, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245732

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease (COPD) has the highest increased risk due to household air pollution arising from biomass fuel burning. However, knowledge on COPD patho-mechanisms is mainly limited to tobacco smoke exposure. In this study, a repeated direct wood smoke (WS) exposure was performed using normal- (bro-ALI) and chronic bronchitis-like bronchial (bro-ALI-CB), and alveolar (alv-ALI) lung mucosa models at air-liquid interface (ALI) to assess broad toxicological end points. METHODS: The bro-ALI and bro-ALI-CB models were developed using human primary bronchial epithelial cells and the alv-ALI model was developed using a representative type-II pneumocyte cell line. The lung models were exposed to WS (10 min/exposure; 5-exposures over 3-days; n = 6-7 independent experiments). Sham exposed samples served as control. WS composition was analyzed following passive sampling. Cytotoxicity, total cellular reactive oxygen species (ROS) and stress responsive NFkB were assessed by flow cytometry. WS exposure induced changes in gene expression were evaluated by RNA-seq (p ≤ 0.01) followed by pathway enrichment analysis. Secreted levels of proinflammatory cytokines were assessed in the basal media. Non-parametric statistical analysis was performed. RESULTS: 147 unique compounds were annotated in WS of which 42 compounds have inhalation toxicity (9 very high). WS exposure resulted in significantly increased ROS in bro-ALI (11.2%) and bro-ALI-CB (25.7%) along with correspondingly increased NFkB levels (bro-ALI: 35.6%; bro-ALI-CB: 18.1%). A total of 1262 (817-up and 445-down), 329 (141-up and 188-down), and 102 (33-up and 69-down) genes were differentially regulated in the WS-exposed bro-ALI, bro-ALI-CB, and alv-ALI models respectively. The enriched pathways included the terms acute phase response, mitochondrial dysfunction, inflammation, oxidative stress, NFkB, ROS, xenobiotic metabolism of AHR, and chronic respiratory disorder. The enrichment of the 'cilium' related genes was predominant in the WS-exposed bro-ALI (180-up and 7-down). The pathways primary ciliary dyskinesia, ciliopathy, and ciliary movement were enriched in both WS-exposed bro-ALI and bro-ALI-CB. Interleukin-6 and tumor necrosis factor-α were reduced (p < 0.05) in WS-exposed bro-ALI and bro-ALI-CB. CONCLUSION: Findings of this study indicate differential response to WS-exposure in different lung regions and in chronic bronchitis, a condition commonly associated with COPD. Further, the data suggests ciliopathy as a candidate pathway in relation to WS-exposure.


Assuntos
Bronquite Crônica , Ciliopatias , Doença Pulmonar Obstrutiva Crônica , Humanos , Bronquite Crônica/induzido quimicamente , Bronquite Crônica/metabolismo , Fumaça/efeitos adversos , Madeira/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Pulmão/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Mucosa , Produtos do Tabaco
3.
Nanotechnology ; 34(19)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36731115

RESUMO

A rapid, clean plasma-chemical technique is demonstrated here, for cost-effective, synthesis of surface vacancy engineered, 2D, molybdenum-oxide nanomaterials, during a one-step, integrated synthesis-hydrogenation process for biomedical applications. A laminar plasma beam populated with O and H radicals impinges on a molybdenum target, out of which molybdenum-oxide nanomaterials are very rapidly generated with controlled surface O vacancies. 2D, dark-blue coloured, nano-flake/ribbon like MoO3-xis produced maximum up to 194 g h-1, the core of which still remains as stoichiometric molybdenum-oxide. These nanomaterials can get heated-up by absorbing energy from a near-infrared (NIR) laser, which enable them as photothermal therapy (PTT) candidate material for the invasive precision therapy of cancer. The surface defects endows the products with robust ferromagnetism at room temperature conditions (maximum saturation-magnetization: 6.58 emu g-1), which is order of magnitude stronger than most other vacancy engineered nanomaterials. These nanometric metal-oxides are observed to be perfectly compatible in animal physiological environment and easily dispersed in an aqueous solution even without any pre-treatment. The MoO3-xnanomaterials are stable against further oxidation even under prolonged atmospheric exposure.In vitroexperiments confirm that they have ideal efficacy for photothermal ablation of human and murine melanoma cancer at relatively lower dose. Duringin vivoPTT treatments, they may be manipulated with a simple external magnetic field for targeted delivery at the malignant tumours. It is demonstrated that commensurate to the neutralization of the malignant cells, the nanomaterials themselves get self-degraded, which should get easily excreted out of the body.


Assuntos
Nanoestruturas , Neoplasias , Animais , Humanos , Camundongos , Molibdênio , Fototerapia/métodos , Neoplasias/tratamento farmacológico , Nanoestruturas/uso terapêutico , Óxidos/uso terapêutico
4.
Environ Monit Assess ; 194(10): 730, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36066693

RESUMO

Nanomaterials (NMs) are currently being used in agricultural soils as part of a new bioremediation (BR) process. In this study, we reviewed the biosynthesis of NMs, as well as their chemical composition and prospective strategies for helpful and sustainable agricultural soil bioremediation (BR). Different types of NMs, such as nanoparticles, nanocomposites, nanocrystals, nano-powders, and nanotubes, are used in agricultural soil reclamation, and they reflect the toxicity of NMs to microorganisms. Plants (Sargassum muticum, Dodonaea viscose, Aloe Vera, Rosemarinus officinalis, Azadirachta indica, Green tea, and so on) and microorganisms (Escherichia coli, Shewanella oneidensis, Pleurotus sp., Klebsiella oxytoca, Aspergillus clavatus, and so on) are the primary sources for the biosynthesis of NMs. By using the BR process, microorganisms, such as bacteria and plants, can immobilize metals and change both inorganic and organic contaminants in the soil. Combining NMs with bioremediation techniques for agricultural soil remediation will be a valuable long-term solution.


Assuntos
Nanoestruturas , Poluentes do Solo , Biodegradação Ambiental , Monitoramento Ambiental , Plantas , Estudos Prospectivos , Solo/química , Poluentes do Solo/análise
5.
Toxicol Appl Pharmacol ; 420: 115532, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33845054

RESUMO

Limited information is available regarding the effects of arsenic exposure on immune function. We have recently reported that chronic exposure to As was associated asthma, as determined by spirometry and respiratory symptoms. Because T helper 2 (Th2)-driven immune responses are implicated in the pathogenesis of allergic diseases, including asthma, we studied the associations of serum Th1 and Th2 mediators with the As exposure markers and the features of asthma among individuals exposed to As. A total of 553 blood samples were selected from the same study subjects recruited in our previous asthma study. Serum levels of Th1 and Th2 cytokines were analyzed by immunoassay. Subjects' arsenic exposure levels (drinking water, hair and nail arsenic concentrations) were determined by inductively coupled plasma mass spectroscopy. Arsenic exposure levels of the subjects showed significant positive associations with serum Th2-mediators- interleukin (IL)-4, IL-5, IL-13, and eotaxin without any significant changes in Th1 mediators- interferon-γ and tumor necrosis factor-α. The ratios of Th2 to Th1 mediators were significantly increased with increasing exposure to As. Notably, most of the Th2 mediators were positively associated with serum levels of total immunoglobulin E and eotaxin. The serum levels of Th2 mediators were significantly higher in the subjects with asthma than those without asthma. The results of our study suggest that the exacerbated Th2-driven immune responses are involved in the increased susceptibility to allergic asthma among individuals chronically exposed to As.


Assuntos
Arsênio/efeitos adversos , Asma/induzido quimicamente , Citocinas/sangue , Células Th1/efeitos dos fármacos , Equilíbrio Th1-Th2/efeitos dos fármacos , Células Th2/efeitos dos fármacos , Poluentes Químicos da Água/efeitos adversos , Adolescente , Adulto , Asma/diagnóstico , Asma/imunologia , Asma/metabolismo , Bangladesh , Carga Corporal (Radioterapia) , Estudos Transversais , Feminino , Humanos , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Células Th1/imunologia , Células Th1/metabolismo , Células Th2/imunologia , Células Th2/metabolismo , Adulto Jovem
6.
Proc Natl Acad Sci U S A ; 115(16): E3616-E3625, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29618610

RESUMO

Locomotion of the nematode Caenorhabditis elegans is a key observable used in investigations ranging from behavior to neuroscience to aging. However, while the natural environment of this model organism is 3D, quantitative investigations of its locomotion have been mostly limited to 2D motion. Here, we present a quantitative analysis of how the nematode reorients itself in 3D media. We identify a unique behavioral state of C. elegans-a roll maneuver-which is an essential component of 3D locomotion in burrowing and swimming. The rolls, associated with nonzero torsion of the nematode body, result in rotation of the plane of dorsoventral body undulations about the symmetry axis of the trajectory. When combined with planar turns in a new undulation plane, the rolls allow the nematode to reorient its body in any direction, thus enabling complete exploration of 3D space. The rolls observed in swimming are much faster than the ones in burrowing; we show that this difference stems from a purely hydrodynamic enhancement mechanism and not from a gait change or an increase in the body torsion. This result demonstrates that hydrodynamic viscous forces can enhance 3D reorientation in undulatory locomotion, in contrast to known hydrodynamic hindrance of both forward motion and planar turns.


Assuntos
Caenorhabditis elegans/fisiologia , Natação/fisiologia , Animais , Hidrodinâmica , Modelos Biológicos , Rotação
7.
BMC Med Educ ; 21(1): 29, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413332

RESUMO

BACKGROUND: Distractor efficiency and the optimum number of functional distractors per item in One Best Answer Questions have been debated. The prevalence of non-functional distractors has led to a reduction in the number of distractors per item with the advantage of adding more items in the test. The existing literature eludes a definite answer to the question of what distractor efficiency best matches excellent psychometric indices. We examined the relationship between distractor efficiency and the psychometric indices of One Best Answer Questions in search of an answer. METHODS: We analysed 350 items used in 7 professional examinations and determined their distractor efficiency and the number of functional distractors per item. The items were sorted into five groups - excellent, good, fair, remediable and discarded based on their discrimination index. We studied how the distractor efficiency and functional distractors per item correlated with these five groups. RESULTS: Correlation of distractor efficiency with psychometric indices was significant but far from perfect. The excellent group topped in distractor efficiency in 3 tests, the good group in one test, the remediable group equalled excellent group in one test, and the discarded group topped in 2 tests. CONCLUSIONS: The distractor efficiency did not correlate in a consistent pattern with the discrimination index. Fifty per cent or higher distractor efficiency, not hundred percent, was found to be the optimum.


Assuntos
Avaliação Educacional , Humanos , Psicometria
8.
Environ Monit Assess ; 193(9): 575, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34392406

RESUMO

Motor vehicles operating on the road are a significant source of Particulate Matter (PM) emissions depending on the fuels used in the vehicles. Gasoline and Diesel vehicles are directly responsible for the tailpipe PM emissions (specifically PM2.5: particles ≤ 2.5 µm), known as primary PM2.5 emissions. The other major direct emissions from the vehicles, which include volatile organic compounds (VOCs), and nitrogen oxides (NOx) contribute to the formation of secondary organic PM, also known as secondary organic aerosols (SOA), through some inter-related chemical reactions. The SOAs are highly toxic and contribute to a portion of total PM emissions. In this research, emission scenarios of both primary PM2.5 and SOA for a car-dependent expanding Australian city (Adelaide) were analyzed. The variability of traffic characteristics on road was considered and conducted a probabilistic emissions inventory for tailpipe primary PM2.5 and precursors, while statistical analysis of the probable chemical conversion ratios was considered for the SOA inventory. It was found that the tailpipe emissions from the vehicles were higher than the air quality standard, while the SOA contribution from the vehicles was not significantly high but contributed to the increase of total PM concentration. The analysis of the chemical transformation of SOA precursors justified the importance of conducting more detailed emissions modelling for sustainable urban air quality planning.


Assuntos
Poluentes Atmosféricos , Material Particulado , Poluentes Atmosféricos/análise , Austrália , Monitoramento Ambiental , Gasolina/análise , Material Particulado/análise , Emissões de Veículos/análise
9.
Mar Policy ; 126: 104422, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33568881

RESUMO

COVID-19 is now a major global health crisis, can lead to severe food crisis unless proper measures are taken. Though a number of scientific studies have addressed the possible impacts of COVID-19 in Bangladesh on variety of issues, problems and food crises associated with aquatic resources and communities are missing. Therefore, this study aimed at bridging the gap in the existing situation and challenges of COVID-19 by linking its impact on aquatic food sector and small-scale fisheries with dependent population. The study was conducted based on secondary data analysis and primary fieldwork. Secondary data focused on COVID-19 overview and number of confirmed, recovered and death cases in Bangladesh; at the same time its connection with small-scale fisheries, aquatic food production, demand and supply was analyzed. Community perceptions were elicited to present how the changes felt and how they affected aquatic food system and small-scale fisheries and found devastating impact. Sudden illness, reduced income, complication to start production and input collection, labor crisis, transportation abstraction, complexity in food supply, weak value chain, low consumer demand, rising commodity prices, creditor's pressure were identified as the primary affecting drivers. Dependent people felt the measures taken by the Government should be based on protecting both the health and food security. Scope of alternative income generating opportunities, rationing system, training and motivational program could improve the situation. The study provides insight into policies adopted by the policy makers to mitigate the effects of the pandemic on aquatic food sector and small-scale fisheries.

10.
Environ Dev Sustain ; 23(6): 9352-9366, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33041644

RESUMO

We performed a global analysis with data from 149 countries to test whether temperature can explain the spatial variability of the spread rate and mortality of COVID-19 at the global scale. We performed partial correlation analysis and linear mixed effect modelling to evaluate the association of the spread rate and motility of COVID-19 with maximum, minimum, average temperatures and diurnal temperature variation (difference between daytime maximum and night-time minimum temperature) and other environmental and socio-economic parameters. After controlling the effect of the duration since the first positive case, partial correlation analysis revealed that temperature was not related with the spatial variability of the spread rate of COVID-19 at the global scale. Mortality was negatively related with temperature in the countries with high-income economies. In contrast, diurnal temperature variation was significantly and positively correlated with mortality in the low- and middle-income countries. Taking the country heterogeneity into account, mixed effect modelling revealed that inclusion of temperature as a fixed factor in the model significantly improved model skill predicting mortality in the low- and middle-income countries. Our analysis suggests that warm climate may reduce the mortality rate in high-income economies, but in low- and middle-income countries, high diurnal temperature variation may increase the mortality risk.

11.
Glob Chang Biol ; 26(7): 4028-4041, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32441438

RESUMO

Atmospheric CO2 (ca ) rise changes the physiology and possibly growth of tropical trees, but these effects are likely modified by climate. Such ca  × climate interactions importantly drive CO2 fertilization effects of tropical forests predicted by global vegetation models, but have not been tested empirically. Here we use tree-ring analyses to quantify how ca rise has shifted the sensitivity of tree stem growth to annual fluctuations in rainfall and temperature. We hypothesized that ca rise reduces drought sensitivity and increases temperature sensitivity of growth, by reducing transpiration and increasing leaf temperature. These responses were expected for cooler sites. At warmer sites, ca rise may cause leaf temperatures to frequently exceed the optimum for photosynthesis, and thus induce increased drought sensitivity and stronger negative effects of temperature. We tested these hypotheses using measurements of 5,318 annual rings from 129 trees of the widely distributed (sub-)tropical tree species, Toona ciliata. We studied growth responses during 1950-2014, a period during which ca rose by 28%. Tree-ring data were obtained from two cooler (mean annual temperature: 20.5-20.7°C) and two warmer (23.5-24.8°C) sites. We tested ca  × climate interactions, using mixed-effect models of ring-width measurements. Our statistical models revealed several significant and robust ca  × climate interactions. At cooler sites (and seasons), ca  × climate interactions showed good agreement with hypothesized growth responses of reduced drought sensitivity and increased temperature sensitivity. At warmer sites, drought sensitivity increased with increasing ca , as predicted, and hot years caused stronger growth reduction at high ca . Overall, ca rise has significantly modified sensitivity of Toona stem growth to climatic variation, but these changes depended on mean climate. Our study suggests that effects of ca rise on tropical tree growth may be more complex and less stimulatory than commonly assumed and require a better representation in global vegetation models.


Assuntos
Dióxido de Carbono , Árvores , Mudança Climática , Florestas , Temperatura , Clima Tropical
12.
Virol J ; 17(1): 90, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32615978

RESUMO

BACKGROUND: Three different genotypes of chikungunya virus (CHIKV) have been classified: East/Central/South African (ECSA), West African (WA), and Asian. Previously, a rapid immunochromatographic (IC) test detecting CHIKV E1-antigen showed high sensitivity for certain ECSA-genotype viruses, but this test showed poor performance against the Asian-genotype virus that is spreading in the American continents. We found that the reactivity of one monoclonal antibody (MAb) used in the IC rapid diagnostic test (RDT) is affected by a single amino acid substitution in E1. Therefore, we developed new MAbs that exhibited specific recognition of all three genotypes of CHIKV. METHODS: Using a combination of the newly generated MAbs, we developed a novel version of the IC RDT with improved sensitivity to Asian-genotype CHIKV. To evaluate the sensitivity, specificity, and cross-reactivity of the new version of the IC RDT, we first used CHIKV isolates and E1-pseudotyped lentiviral vectors. We then used clinical specimens obtained in Aruba in 2015 and in Bangladesh in 2017 for further evaluation of RDT sensitivity and specificity. Another alphavirus, sindbis virus (SINV), was used to test RDT cross-reactivity. RESULTS: The new version of the RDT detected Asian-genotype CHIKV at titers as low as 10^4 plaque-forming units per mL, a concentration that was below the limit of detection of the old version. The new RDT had sensitivity to the ECSA genotype that was comparable with that of the old version, yielding 92% (92 out of 100) sensitivity (95% confidence interval 85.0-95.9) and 100% (100 out of 100) specificity against a panel of 100 CHIKV-positive and 100 CHIKV-negative patient sera obtained in the 2017 outbreak in Bangladesh. CONCLUSIONS: Our newly developed CHIKV antigen-detecting RDT demonstrated high levels of sensitivity and lacked cross-reactivity against SINV. These results suggested that our new version of the CHIKV E1-antigen RDT is promising for use in areas in which the Asian and ECSA genotypes of CHIKV circulate. Further validation with large numbers of CHIKV-positive and -negative clinical samples is warranted. (323 words).


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos Virais/imunologia , Febre de Chikungunya/diagnóstico , Vírus Chikungunya/genética , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Antivirais/sangue , Vírus Chikungunya/classificação , Chlorocebus aethiops , Cromatografia de Afinidade , Reações Cruzadas , Genótipo , Células HEK293 , Humanos , Testes Imunológicos , Sensibilidade e Especificidade , Células Vero , Proteínas do Envelope Viral/genética
13.
Lupus ; 29(8): 825-835, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32479241

RESUMO

BACKGROUND: Low-density lipoprotein (LDL) levels are increased by proprotein convertase subtilisin kexin 9 (PCSK9) which targets the LDL receptor. We recently reported that PCSK9 ameliorates dendritic cell (DC) activation by oxidized LDL (OxLDL), which is abundant in atherosclerotic plaques and is also associated with cardiovascular disease (CVD) in systemic lupus erythematosus (SLE). Here, we investigated the role of PCSK9 in SLE. METHODS: PCSK9 levels were determined by ELISA among SLE patients (N = 109) and age- and sex-matched population-based controls (N = 91). Common carotid intima-media thickness (IMT) and plaque occurrence were determined by B-mode ultrasound. Plaques were graded by echogenicity. Human peripheral blood monocytes from SLE patients or controls were differentiated into DCs. The effects of PCSK9 and its inhibition by silencing were studied. RESULTS: PCSK9 levels were non-significantly higher among SLE-patients compared to controls but significantly associated with SLE disease activity, as determined by the Systemic Lupus Activity Measure (p = 0.020) or the SLE Disease Activity Index (p = 0.0178). There was no association between PCSK9 levels and atherosclerosis as determined by IMT, prevalence of plaques or echolucent (potentially vulnerable) plaques. PCSK9 levels were significantly associated with CVD among SLE patients but not after adjusting for age. OxLDL induced PCSK9 in DCs and DC maturation with increased expression of CD86 and HLA-DR. The effects were significantly stronger in DCs from SLE patients than from controls. Silencing of PCSK9 abolished OxLDL-induced DC maturation. CONCLUSIONS: PCSK9 is associated with disease activity in SLE. One underlying cause could be OxLDL promoting DC activation which depends on PCSK9. OxLDL induces PCSK9 - an effect which is higher among SLE patients. PCSK9 could play an unexpected immunological role in SLE.


Assuntos
Lúpus Eritematoso Sistêmico/sangue , Pró-Proteína Convertase 9/sangue , Adulto , Espessura Intima-Media Carotídea , Estudos de Casos e Controles , Feminino , Humanos , Lipoproteínas LDL/sangue , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/diagnóstico por imagem , Pró-Proteína Convertase 9/imunologia , Fatores de Risco
14.
Int J Med Sci ; 17(1): 103-111, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929744

RESUMO

Beyond their role in bone and lung homeostasis, mesenchymal stem cells (MSCs) are becoming popular in cell therapy. Various insults may disrupt the repair mechanisms involving MSCs. One such insult is smoking, which is a major risk factor for osteoporosis and respiratory diseases. Upon cigarette smoke-induced damage, a series of reparatory mechanisms ensue; one such mechanism involves Glycosaminoglycans (GAG). One of these GAGs, namely hyaluronic acid (HA), serves as a potential therapeutic target in lung injury. However, much of its mechanisms of action through its major receptor CD44 remains unexplored. Our previous studies have identified and functionally validated that both cortactin (CTTN: marker of motility) and Survivin (BIRC5: required for cell survival) act as novel HA/CD44-downstream transcriptional targets underpinning cell motility. Here, human MSCs were treated with "Water-pipe" smoke to investigate the effects of cigarette smoke condensate (CSC) on these HA-CD44 novel signaling pathways. Our results show that CSC decreased the expression of both CD44 and its downstream targets CTTN and BIRC5 in MSCs, and that HA reversed these effects. Interestingly, CSC inhibited migration and invasion of MSCs upon CD44-targeted RNAi treatment. This shows the importance of CD44-HA/CTTN and CD44-HA/BIRC5 signaling pathways in MSC motility, and further suggests that these signaling pathways may provide a novel mechanism implicated in migration of MSCs during repair of lung tissue injury. These findings suggest that one should use caution before utilizing MSC from donors with history of smoking, and further pave the way towards the development of targeted therapeutic approaches against CD44-associated diseases.


Assuntos
Fumar Cigarros/efeitos adversos , Cortactina/genética , Receptores de Hialuronatos/genética , Lesão Pulmonar/genética , Survivina/genética , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Glicosaminoglicanos/genética , Humanos , Ácido Hialurônico/genética , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/patologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/patologia , Transdução de Sinais/efeitos dos fármacos , Fumar/efeitos adversos
15.
Emerg Infect Dis ; 25(2): 370-372, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30666947

RESUMO

In 2017, an unprecedented increase in febrile illness was observed in Dhaka, Bangladesh. Real-time reverse transcription PCR confirmed that 603 (40.2%) of 1,500 cases were chikungunya fever. Phylogenetic analysis revealed circulation of the non-A226V East/Central/South African genotype of chikungunya virus in Bangladesh.


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya/genética , Surtos de Doenças , Genótipo , Bangladesh/epidemiologia , Febre de Chikungunya/história , Vírus Chikungunya/classificação , História do Século XXI , Humanos , Filogenia , RNA Viral , Proteínas Virais/genética
16.
Virol J ; 16(1): 102, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31416485

RESUMO

BACKGROUND: Dengue virus (DENV) infection is one of the biggest challenges for human health in the world. In addition, a secondary DENV infection sometimes causes dengue hemorrhagic fever (DHF), which frequently leads to death. For this reason, accurate diagnosis record management is useful for prediction of DHF. Therefore, the demand for DENV rapid diagnosis tests (RDTs) is increasing because these tests are easy and rapid to use. However, commercially available RDTs often show low sensitivity for DENV and cross-reactivity against other flaviviruses, especially Zika virus (ZIKV). METHODS: We developed two types of novel DENV non-structural protein 1 (NS1) detection RDTs, designated TKK-1st and TKK-2nd kits. Specificities of the monoclonal antibodies (MAbs) used in these kits were confirmed by enzyme-linked immuno-sorbent assay (ELISA), dot blot, and western blot using recombinant NS1 proteins and synthetic peptides. For evaluation of sensitivity, specificity, and cross-reactivity of the novel DENV NS1 RDTs, we first used cultured DENV and other flaviviruses, ZIKV and Japanese encephalitis virus (JEV). We then used clinical specimens obtained in Bangladesh in 2017 for further evaluation of kit sensitivity and specificity in comparison with commercially available RDTs. In addition, RNA extracted from sera were used for viral genome sequencing and genotyping. RESULTS: Epitopes of three out of four MAbs used in the two novel RDTs were located in amino acid positions 100 to 122 in the NS1 protein, a region that shows low levels of homology with other flaviviruses. Our new kits showed high levels of sensitivity against various serotypes and genotypes of DENV and exhibited high levels of specificity without cross-reactivity against ZIKV and JEV. In clinical specimens, our RDTs showed sensitivities of 96.0% (145/151, TKK-1st kit) and 96.7% (146/151, TKK-2nd kit), and specificities of 98.0% (98/100, TKK-1st kit and TKK-2nd kit). On the other hand, in the case of the commercially available SD Bioline RDT, sensitivity was 83.4% (126/151) and specificity was 99.0% (99/100) against the same clinical specimens. CONCLUSIONS: Our novel DENV NS1-targeting RDTs demonstrated high levels of sensitivity and lacked cross-reactivity against ZIKV and JEV compared with commercially available RDTs.


Assuntos
Vírus da Dengue/isolamento & purificação , Dengue/diagnóstico , Kit de Reagentes para Diagnóstico/normas , Proteínas não Estruturais Virais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Bangladesh , Western Blotting , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Humanos , Immunoblotting , Limite de Detecção , Proteínas Recombinantes/genética , Sensibilidade e Especificidade , Zika virus
17.
Hemoglobin ; 43(3): 162-165, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31339392

RESUMO

In Bangladesh, the practice of ß-thalassemia (ß-thal) carrier screening and prenatal diagnosis (PND) by ß-globin gene sequencing has been initiated to prevent the birth of affected children. The study aimed to describe a novel de novo mutation of the ß-globin gene and its clinical implication. Out of 100 Bangladeshi ß-thal carrier families, one patient with hematological and clinical features associated with ß-thal and her parents were included. Molecular characterizations of ß-globin gene mutations were performed by direct sequencing. A novel nucleotide deletion mutation at codon 8 in the first exon of the ß-globin gene (HBB: c.27delG) was found in a 1-year-old child of the studied family in a heterozygous state along with common Hb E (HBB: c.79G>A). The mutation caused a frameshift to a new stop codon at codon 18 resulting in a ß0-thal phenotype. The proband exhibited a ß-thal intermedia (ß-TI)-like genotype, however, showed ß-thal major (ß-TM)-like complications and was transfusion-dependent. Her mother had a profile consistent with the Hb E trait, while the father had normal hematological indices. Mutation analyses revealed the mother to be heterozygous for Hb E, while the father had a normal genotype. The novel mutation was assumed to be inherited de novo by the paternity test. The study documented a novel pathogenic mutation in the ß-globin gene in a Bangladeshi family by ß-globin gene sequencing.


Assuntos
Códon , Globinas beta/genética , Talassemia beta/diagnóstico , Talassemia beta/genética , Alelos , Sequência de Aminoácidos , Substituição de Aminoácidos , Bangladesh , Sequência de Bases , Biomarcadores , Análise Mutacional de DNA , Índices de Eritrócitos , Éxons , Feminino , Mutação da Fase de Leitura , Genótipo , Humanos , Lactente , Fenótipo , Talassemia beta/sangue
18.
Tohoku J Exp Med ; 244(3): 187-193, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29503347

RESUMO

The cytokine interleukin-21 (IL-21) is mainly produced from activated CD4+ T cells and natural killer T (NKT) cells. IL-21 enhances the proliferation and differentiation of T cells and B cells and also increases cytotoxicity of CD8+ T cells and NK cells through the IL-21 receptor and its downstream signaling molecules such as signal transducers and activator of transcription 3 (STAT3) and extracellular signal-regulated kinase 1/2 (ERK1/2). SH2 domain-containing tyrosine phosphatase (SHP-2) is ubiquitously expressed, including hematopoietic cells. SHP-2 has been implicated in the regulation of IL-6 and IL-3 signaling, but its function in IL-21 signaling has not been investigated. Therefore, we studied the role of SHP-2 in IL-21 signaling by SHP-2 overexpression and knockdown experiments. For the SHP-2 overexpression, we used 293T human embryonic kidney cells, in which the IL-21 receptor system were easily reconstituted and high amounts of exogenous SHP-2 were expressed by vector transfection. In 293T cells, overexpressed SHP-2 caused the increase in the degree of the IL-21-induced ERK1/2 activation. Subsequently, SHP-2 knockdown experiments were performed in the mouse pro-B cell line, BAF21RWT-1, which constitutively expresses human IL-21 receptor and proliferates in an IL-21-dependent manner. SHP-2 knockdown reduced the degree of the IL-21-induced ERK1/2 activation and suppressed cell proliferation. These results suggest that SHP-2 may augment the ERK1/2 activity and cell proliferation activity in IL-21 signaling. We propose that SHP-2 is involved in the IL-21-mediated ERK1/2 activation and cell proliferation.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Interleucinas/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Janus Quinases/metabolismo , Camundongos , Fosforilação/efeitos dos fármacos , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Quinases raf/metabolismo
19.
J Anim Physiol Anim Nutr (Berl) ; 102(6): 1450-1463, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30099783

RESUMO

This study aimed to evaluate in vitro fermentation characteristics, microbial protein synthesis and microbial community composition when replacing maize silage (MS) with red clover silage (RCS) in total mixed rations (TMR) of dairy cows. Treatments included TMR containing forage (MS and RCS) and concentrates (0.75:0.25) with targeted proportions (dry matter (DM) basis) of RCS in TMR of 0.15 (RCS15 ), 0.30 (RCS30 ), 0.45 (RCS45 ), and 0.60 (RCS60 ), in substitution of MS. Samples of the TMR were incubated using the in vitro Ankom RF technique with a mixture of rumen fluid and buffer solution (1:2 v/v) for 8 and 24 hr. Gas production and total short-chain fatty acids concentration did not differ between diets, whereas ammonia-nitrogen concentration increased with increasing level of RCS. Acetate proportion was not affected by RCS level, but propionate showed a linear increase with increasing level of RCS at the expenses of butyrate. Branched fatty acids proportions linearly declined, reflecting a reduced deamination of true protein. Gene copy numbers of protozoa linearly decreased with increasing RCS levels, while total numbers of bacteria and methanogens were not affected by diet. The amylolytic bacteria Ruminobacter amylophillus and Prevotella bryantii showed evidence to increase with higher RCS levels after 8 hr and 24 hr, respectively, whereas no effects of diet where observed for the fibrolytic bacteria Ruminococcus albus, Ruminococcus flavefaciens and Fibrobacter succinogenes. Concentrations of purine bases, and total N production in liquid-associated microbes declined with increasing RCS levels, suggesting a negative impact of this feed on microbial growth. The findings of this study suggest that in general, microbial protein synthesis might be impaired by the substitution of MS by RCS, therefore caution should be taken when formulating diets for dairy cows using high levels of RCS as ingredient.


Assuntos
Bactérias/metabolismo , Rúmen/fisiologia , Silagem/análise , Trifolium/química , Zea mays/química , Animais , Digestão , Fermentação , Biossíntese de Proteínas/fisiologia
20.
Clin Immunol ; 166-167: 27-37, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27102765

RESUMO

OBJECTIVES: Phosphorylcholine (PC) and malondialdehyde (MDA) are generated during lipid peroxidation and form adducts with proteins as albumin as studied herein. Atherosclerosis and cardiovascular disease (CVD) are increased in systemic lupus erythematosus (SLE). We here investigate the role and regulation of IgM antibodies against PC (anti-PC) and MDA (anti-MDA). METHODS: IgM anti-PC and anti-MDA in SLE patients (n=114) were compared with age- and sex-matched population-based controls (n=108). Common carotid intima-media thickness (IMT) and plaque occurrence were determined by B-mode ultrasound. Plaques were graded according to echogenicity (potentially vulnerability). Production of IgM anti-PC and anti-MDA by B cells was determined by ELISA and ELISPOT. The effect of anti-PC and anti-MDA on macrophage uptake of apoptotic cells and oxidative stress was studied by flow cytometry. RESULTS: Above 66rd percentile together, IgM anti-PC and anti-MDA were striking protection markers for plaque prevalence and echolucency in SLE (OR: 0.08, CI: 0.01-0.46 and OR: 0.10, CI: 0.01-0.82), respectively, and risk markers for plaque prevalence when below 33rd percentile: OR: 3.79, CI: (1.10-13.00). In vitro, IgM anti-PC and anti-MDA were much higher when B cells were co-cultured with CD3 T cells. Anti-HLA-, anti-CD40 antibody or CD40 silencing abolished these effects. Uptake of apoptotic cells was increased by IgM anti-PC and anti-MDA. MDA induced increased oxidative stress, which was inhibited by IgM anti-MDA. CONCLUSIONS: Unexpectedly, both IgM anti-MDA and IgM anti-PC are T-cell dependent and especially together, are strong protection markers for atherosclerosis in SLE. Underlying mechanisms include increased phagocytosis of apoptotic cells and decrease of oxidative stress.


Assuntos
Aterosclerose/imunologia , Imunoglobulina M/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Malondialdeído/imunologia , Fosforilcolina/imunologia , Adulto , Apoptose/imunologia , Aterosclerose/complicações , Aterosclerose/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biomarcadores/metabolismo , Complexo CD3/imunologia , Complexo CD3/metabolismo , Espessura Intima-Media Carotídea , Células Cultivadas , Técnicas de Cocultura , Ensaio de Imunoadsorção Enzimática , ELISPOT , Feminino , Humanos , Imunoglobulina M/metabolismo , Células Jurkat , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/metabolismo , Masculino , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Estresse Oxidativo/imunologia , Fagocitose/imunologia , Fosforilcolina/metabolismo , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Ultrassonografia
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