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1.
Mol Ther ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38946142

RESUMO

The chimeric antigen receptor (CAR) derived from the CD30 specific murine antibody, HRS-3, has produced promising clinical efficacy with a favorable safety profile in the treatment of relapsed or refractory CD30-positive lymphomas. However, persistence of the autologous CAR T cells was brief, and many patients relapsed a year after treatment. The lack of persistence may be attributed to the use of a wildtype IgG1 spacer that can associate with Fc receptors. We first identified the cysteine rich domain (CRD) 5 of CD30 as the primary binding epitope of HRS-3 and armed with this insight, attempted to improve the HRS-3 CAR functionality with a panel of novel spacer designs. We demonstrate that HRS-3 CARs with OX40 and 4-1BB derived spacers exhibited similar anti-tumor efficacy, circumvented interactions with Fc receptors and secreted lower levels of cytokines in vitro than a CAR employing the IgG1 spacer. Humanization of the HRS-3 scFv coupled with the 4-1BB spacer preserved potent on-target, on-tumor efficacy, and on-target, off-tumor safety. In a lymphoma mouse model of high tumor burden, T cells expressing a humanized HRS-3 CD30.CARs with the 4-1BB spacer potently killed tumors with low levels of circulating inflammatory cytokines, providing a promising candidate for future clinical development in the treatment of CD30-positive malignancies.

2.
J Mol Cell Cardiol ; 186: 125-137, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008210

RESUMO

N-terminal cardiac myosin-binding protein C (cMyBP-C) domains (C0-C2) bind to thick (myosin) and thin (actin) filaments to coordinate contraction and relaxation of the heart. These interactions are regulated by phosphorylation of the M-domain situated between domains C1 and C2. In cardiomyopathies and heart failure, phosphorylation of cMyBP-C is significantly altered. We aimed to investigate how cMyBP-C interacts with myosin and actin. We developed complementary, high-throughput, C0-C2 FRET-based binding assays for myosin and actin to characterize the effects due to 5 HCM-linked variants or functional mutations in unphosphorylated and phosphorylated C0-C2. The assays indicated that phosphorylation decreases binding to both myosin and actin, whereas the HCM mutations in M-domain generally increase binding. The effects of mutations were greatest in phosphorylated C0-C2, and some mutations had a larger effect on actin than myosin binding. Phosphorylation also altered the spatial relationship of the probes on C0-C2 and actin. The magnitude of these structural changes was dependent on C0-C2 probe location (C0, C1, or M-domain). We conclude that binding can differ between myosin and actin due to phosphorylation or mutations. Additionally, these variables can change the mode of binding, affecting which of the interactions in cMyBP-C N-terminal domains with myosin or actin take place. The opposite effects of phosphorylation and M-domain mutations is consistent with the idea that cMyBP-C phosphorylation is critical for normal cardiac function. The precision of these assays is indicative of their usefulness in high-throughput screening of drug libraries for targeting cMyBP-C as therapy.


Assuntos
Citoesqueleto de Actina , Actinas , Proteínas de Transporte , Actinas/metabolismo , Fosforilação , Citoesqueleto de Actina/metabolismo , Miosinas/genética , Miosinas/metabolismo , Mutação
3.
Environ Sci Technol ; 58(12): 5524-5533, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38466636

RESUMO

The high environmental concentrations, persistence, and toxicity of synthetic musk compounds (SMCs) necessitate a better grasp of their fate in wastewater treatment plants (WWTPs). To investigate the importance of WWTPs as pathways of SMCs to the environment, air and wastewater samples were collected at four WWTPs in Ontario, Canada. Polycyclic musks (PCMs) were present at higher concentrations than nitro musks (NMs) and macrocyclic musks (MCMs). Three PCMs [galaxolide (HHCB), tonalide (AHTN), and iso-E super (OTNE)] were the most abundant compounds (0.30-680 ng/m3 in air, 0.40-15 µg/L in influent, and 0.007-6.0 µg/L in effluent). Analyses of multiyear data suggest that risk management measures put in place have been effective in reducing the release of many SMCs into the environment. The highest removal efficiency, up to almost 100% of some SMCs, was observed for the plant with the longest solid retention time. A fugacity-based model was established to simulate the transport and fate of SMCs in the WWTP, and good agreement was obtained between the measured and modeled values. These findings indicate that the levels of certain SMCs discharged into the atmospheric and aquatic environments were substantial, potentially resulting in exposure to both humans and wildlife.


Assuntos
Ácidos Graxos Monoinsaturados , Poluentes Químicos da Água , Purificação da Água , Humanos , Poluentes Químicos da Água/análise , Águas Residuárias , Ontário , Benzopiranos/análise
5.
Proc Natl Acad Sci U S A ; 115(35): E8143-E8152, 2018 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-30104387

RESUMO

Mutations in ß-cardiac myosin, the predominant motor protein for human heart contraction, can alter power output and cause cardiomyopathy. However, measurements of the intrinsic force, velocity, and ATPase activity of myosin have not provided a consistent mechanism to link mutations to muscle pathology. An alternative model posits that mutations in myosin affect the stability of a sequestered, super relaxed state (SRX) of the protein with very slow ATP hydrolysis and thereby change the number of myosin heads accessible to actin. Here we show that purified human ß-cardiac myosin exists partly in an SRX and may in part correspond to a folded-back conformation of myosin heads observed in muscle fibers around the thick filament backbone. Mutations that cause hypertrophic cardiomyopathy destabilize this state, while the small molecule mavacamten promotes it. These findings provide a biochemical and structural link between the genetics and physiology of cardiomyopathy with implications for therapeutic strategies.


Assuntos
Benzilaminas/química , Uracila/análogos & derivados , Miosinas Ventriculares/química , Animais , Benzilaminas/farmacologia , Cardiomegalia/enzimologia , Cardiomegalia/genética , Humanos , Músculo Esquelético/enzimologia , Mutação , Suínos , Porco Miniatura , Uracila/química , Uracila/farmacologia , Miosinas Ventriculares/genética , Miosinas Ventriculares/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-31818819

RESUMO

Polymyxin B-based combinations are increasingly prescribed as a last-line option against extensively drug-resistant (XDR) Acinetobacter baumannii It is unknown if such combinations can result in the development of nondividing persister cells in XDR A. baumannii We investigated persister development upon exposure of XDR A. baumannii to polymyxin B-based antibiotic combinations using flow cytometry. Time-kill studies (TKSs) were conducted in three nonclonal XDR A. baumannii strains with 5 log10 CFU/ml bacteria against polymyxin B alone and polymyxin B-based two-drug combinations over 24 h. At different time points, samples were obtained and enumerated by viable plating and flow cytometry. Propidium iodide and carboxyfluorescein succinimidyl ester dyes were used to differentiate between live and dead cells and between dividing and nondividing cells, respectively, at the single-cell level, and nondividing live cells were resuscitated and characterized phenotypically. Our results from viable plating showed that polymyxin B plus meropenem and polymyxin B plus rifampin were each bactericidal (>99.9% kill compared to the initial inoculum) against 2/3 XDR A. baumannii strains at 24 h. By flow cytometry, however, none of the combinations were bactericidal against XDR A. baumannii at 24 h. Further analysis using cellular dyes in flow cytometry revealed that upon exposure to polymyxin B-based combinations, XDR A. baumannii entered a viable but nondividing persister state. These bacterial cells reinitiated division upon the removal of antibiotic pressure and did not have a growth deficit compared to the parent strain. We conclude that persister cells develop in XDR A. baumannii upon exposure to polymyxin B-based combinations and that nonplating methods appear to complement viable-plating methods in describing the killing activity of polymyxin B-based combinations against XDR A. baumannii.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Polimixina B/farmacologia , Citometria de Fluxo , Meropeném/farmacologia , Testes de Sensibilidade Microbiana
7.
BMC Public Health ; 18(1): 1113, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30208869

RESUMO

BACKGROUND: Quality of life (QOL) is an important component in assessing people's health. Environmental quality can influence people's QOL in the physical health, psychological, social relationships and environment domains. QOL in the four domains, overall QOL and general heath of residents living in the Kowloon Peninsula of Hong Kong were assessed. The association between satisfaction with the neighborhood environment and QOL, and health-related behaviors which mediated the effect were investigated. METHODS: A sample of 317 residents completed a questionnaire which comprised the WHOQOL-BREF (Hong Kong version) to assess QOL, the International Physical Activity Questionnaire (IPAQ) to study physical activities, and questions on satisfaction with the neighborhood environment, health-related behaviors and socio-demographics. One-way ANOVA and linear regression were used to study the associations between environmental satisfaction and QOL in the four domains, overall QOL and general health, followed by assessing the relationships between environmental satisfaction and the potential health-related behavior mediators with regression tests. Mediation analysis was conducted using multiple linear regressions to study the effects of environmental satisfaction on QOL in the four domains, overall QOL and general health, as well as the potential mediating roles played by various health-related behaviors. A P-value of < 0.05 was considered as statistically significant. RESULTS: The residents had a relatively higher physical health mean score of 70.83 ± 12.69, and a lower environmental mean score of 61.98 ± 13.76. Moderate satisfaction with the neighborhood environment had a significant relationship with QOL in the psychological domain (ß = 0.170, P = 0.006), however, this effect was partially mediated by the non-smoking behavior of the residents (ß = 0.143, P = 0.022). CONCLUSIONS: Our residents had lower QOL in the physical health and psychological domains but similar QOL in the social relationships and environmental domains compared to other countries. Only QOL in the psychological domain could be predicted by the satisfaction with the neighborhood environment, and non-smoking status was a partial mediator of the effect of moderate environmental satisfaction on QOL in the psychological domain. Refrain from smoking seems to be able to lower the influence of neighborhood environment on people's QOL in the psychological domain to a certain extent.


Assuntos
Comportamentos Relacionados com a Saúde , Satisfação Pessoal , Qualidade de Vida , Características de Residência , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/psicologia , Inquéritos e Questionários , Adulto Jovem
8.
Int J Health Geogr ; 16(1): 8, 2017 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-28228102

RESUMO

BACKGROUND: The prevalence of overweight is increasing and the effectiveness of various weight management and exercise programs varied. An augmented reality smartphone game, Pokémon Go, appears to increase activity levels of players. This study assessed the players and ex-players' frequencies and durations of staying outdoors, and walking/jogging before and during the time they played Pokémon Go, evaluated the physical activity levels of players, ex-players and non-players, and investigated the potential factors which determined their play statuses. METHODS: Students in a university answered an online-questionnaire survey. The IPAQ-short form was incorporated to measure vigorous-intensity activities, moderate-intensity activities and walking. Chi square tests were used to compare frequencies and durations of staying outdoors and walking/jogging, health discomforts and physical activity levels between players, ex-players and non-players. Wilcoxon signed ranks tests were performed to assess the changes prior to and during the time when the players and ex-players played Pokémon Go. Logistic regression analyses were performed to assess factors contributing to playing, quitting or not playing Pokémon Go. RESULTS: 644 university students answered the questionnaire. Compared with the ex-players, the players were significantly more frequent to stay outdoors when playing Pokémon Go (P < 0.001), walk/jog to a location to catch Pokémon, to Pokéstops or Gyms (P < 0.005), as well as walking/jogging to hatch eggs (P < 0.001). Players who never or rarely walked/jogged before spent a mean of 108.19 ± 158.21 min/week to walk/jog in order to play the game which is equivalent to burning 357 kcal/week for a 60-kg person walking a moderate pace. Compared with the non-players, players were more likely to be aged 18-25 years [OR (95% CI) 3.28 (1.28-8.40), P = 0.013], never [OR (95% CI) 10.51 (1.12-98.57), P = 0.039] or rarely [OR (95% CI) 4.00 (1.95-8.23), P < 0.001] stayed outdoors and rarely walked/jogged prior to playing the game [OR (95% CI) 3.88 (1.86-8.05), P < 0.001]. However, there was no significant difference in physical activity levels between the three groups (P = 0.573). CONCLUSIONS: Players who used to be sedentary benefited the most from Pokémon Go. The game can be used as a starting point for sedentary people to begin an active lifestyle. The impact of Pokémon Go on physical activity can provide insights to public health workers in using novel strategies in health promotion.


Assuntos
Exercício Físico/fisiologia , Estilo de Vida Saudável/fisiologia , Estudantes , Universidades/tendências , Jogos de Vídeo/tendências , Adolescente , Adulto , Estudos Transversais , Exercício Físico/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso/epidemiologia , Sobrepeso/prevenção & controle , Sobrepeso/psicologia , Projetos Piloto , Estudantes/psicologia , Inquéritos e Questionários , Jogos de Vídeo/psicologia , Adulto Jovem
9.
Environ Sci Technol ; 50(14): 7409-15, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27309668

RESUMO

Fourteen organophosphate esters (OPEs) were measured in the filter fraction of 117 active air samples from yearly ship-based sampling campaigns (2007-2013) and two land-based stations in the Canadian Arctic, to assess trends and long-range transport potential of OPEs. Four OPEs were detected in up to 97% of the samples, seven in 50% or less of the samples, and three were not detected. Median concentrations of ∑OPEs were 237 and 50 pg m(-3) for ship- and land-based samples, respectively. Individual median concentrations ranged from below detection to 119 pg m(-3) for ethanol, 2-chloro-, phosphate (3:1) (TCEP). High concentrations of up to 2340 pg m(-3) were observed for Tri-n-butyl phosphate (TnBP) at a land-based sampling location in Resolute Bay from 2012, whereas it was only detected in one ship-based sample at a concentration below 100 pg m(-3). Concentrations of halogenated OPEs seemed to be driven by river discharge from the Nelson and Churchill Rivers (Manitoba) and Churchill River and Lake Melville (Newfoundland and Labrador). In contrast, nonhalogenated OPE concentrations appeared to have diffuse sources or local sources close to the land-based sampling stations. Triphenyl phosphate (TPhP) showed an apparent temporal trend with a doubling-time of 11 months (p = 0.044). The results emphasize the increasing relevance of halogenated and nonhalogenated OPEs as contaminants in the Arctic.


Assuntos
Monitoramento Ambiental , Ésteres , Canadá , Organofosfatos , Rios
10.
J Immunol ; 193(2): 496-509, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24943219

RESUMO

The Blomia tropicalis dust mite is prevalent in tropical and subtropical regions of the world. Although it is a leading cause of asthma, little is known how it induces allergy. Using a novel murine asthma model induced by intranasal exposure to B. tropicalis, we observed that a single intranasal sensitization to B. tropicalis extract induces strong Th2 priming in the lung draining lymph node. Resident CD11b(+) dendritic cells (DCs) preferentially transport Ag from the lung to the draining lymph node and are crucial for the initiation of Th2 CD4(+) T cell responses. As a consequence, mice selectively deficient in CD11b(+) DCs exhibited attenuated Th2 responses and more importantly did not develop any allergic inflammation. Conversely, mice deficient in CD103(+) DCs and CCR2-dependent monocyte-derived DCs exhibited similar allergic inflammation compared with their wild-type counterparts. We also show that CD11b(+) DCs constitutively express higher levels of GM-CSF receptor compared with CD103(+) DCs and are thus selectively licensed by lung epithelial-derived GM-CSF to induce Th2 immunity. Taken together, our study identifies GM-CSF-licensed CD11b(+) lung DCs as a key component for induction of Th2 responses and represents a potential target for therapeutic intervention in allergy.


Assuntos
Células Dendríticas/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Pulmão/imunologia , Ácaros/imunologia , Células Th2/imunologia , Administração Intranasal , Transferência Adotiva , Animais , Asma/imunologia , Asma/metabolismo , Antígeno CD11b/imunologia , Antígeno CD11b/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/transplante , Células Dendríticas/metabolismo , Células Dendríticas/transplante , Feminino , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Imunização/métodos , Interleucina-4/imunologia , Interleucina-4/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ácaros/metabolismo , Ovalbumina/imunologia , Células Th2/metabolismo , Extratos de Tecidos/administração & dosagem , Extratos de Tecidos/imunologia
11.
Blood ; 122(22): 3666-77, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24113869

RESUMO

Lymphangiogenesis is an important physiological response to inflammatory insult, acting to limit inflammation. Macrophages, dendritic cells, and lymphocytes are known to drive lymphangiogenesis. In this study, we show that neutrophils recruited to sites of inflammation can also coordinate lymphangiogenesis. In the absence of B cells, intranodal lymphangiogenesis induced during prolonged inflammation as a consequence of immunization is dependent on the accumulation of neutrophils. When neutrophils are depleted in wild-type mice developing skin inflammation in response to immunization or contact hypersensitization, lymphangiogenesis is decreased and local inflammation is increased. We demonstrate that neutrophils contribute to lymphangiogenesis primarily by modulating vascular endothelial growth factor (VEGF)-A bioavailability and bioactivity and, to a lesser extent, secreting VEGF-D. We further show that neutrophils increased VEGF-A bioavailability and bioactivity via the secretion of matrix metalloproteinases 9 and heparanase. Together, these findings uncover a novel function for neutrophils as organizers of lymphangiogenesis during inflammation.


Assuntos
Inflamação/etiologia , Inflamação/metabolismo , Linfangiogênese/fisiologia , Neutrófilos/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator D de Crescimento do Endotélio Vascular/metabolismo , Animais , Linfócitos B/imunologia , Dermatite/etiologia , Dermatite/metabolismo , Dermatite/patologia , Feminino , Glucuronidase/metabolismo , Inflamação/patologia , Linfangiogênese/imunologia , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neutrófilos/imunologia , Neutrófilos/patologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
12.
Environ Sci Technol ; 49(23): 13844-52, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26196214

RESUMO

The Arctic has been contaminated by legacy organochlorine pesticides (OCPs) and currently used pesticides (CUPs) through atmospheric transport and oceanic currents. Here we report the time trends and air-water exchange of OCPs and CUPs from research expeditions conducted between 1993 and 2013. Compounds determined in both air and water were trans- and cis-chlordanes (TC, CC), trans- and cis-nonachlors (TN, CN), heptachlor exo-epoxide (HEPX), dieldrin (DIEL), chlorobornanes (ΣCHBs and toxaphene), dacthal (DAC), endosulfans and metabolite endosulfan sulfate (ENDO-I, ENDO-II, and ENDO SUL), chlorothalonil (CHT), chlorpyrifos (CPF), and trifluralin (TFN). Pentachloronitrobenzene (PCNB and quintozene) and its soil metabolite pentachlorothianisole (PCTA) were also found in air. Concentrations of most OCPs declined in surface water, whereas some CUPs increased (ENDO-I, CHT, and TFN) or showed no significant change (CPF and DAC), and most compounds declined in air. Chlordane compound fractions TC/(TC + CC) and TC/(TC + CC + TN) decreased in water and air, while CC/(TC + CC + TN) increased. TN/(TC + CC + TN) also increased in air and slightly, but not significantly, in water. These changes suggest selective removal of more labile TC and/or a shift in chlordane sources. Water-air fugacity ratios indicated net volatilization (FR > 1.0) or near equilibrium (FR not significantly different from 1.0) for most OCPs but net deposition (FR < 1.0) for ΣCHBs. Net deposition was shown for ENDO-I on all expeditions, while the net exchange direction of other CUPs varied. Understanding the processes and current state of air-surface exchange helps to interpret environmental exposure and evaluate the effectiveness of international protocols and provides insights for the environmental fate of new and emerging chemicals.


Assuntos
Poluentes Atmosféricos/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poluentes Químicos da Água/análise , Regiões Árticas , Clordano/análise , Clordano/química , Endossulfano/análogos & derivados , Endossulfano/análise , Endossulfano/química , Monitoramento Ambiental/métodos , Gases/análise , Gases/química , Hidrocarbonetos Clorados/química , Oceanos e Mares , Praguicidas/química , Água do Mar/análise , Água do Mar/química , Poluentes do Solo/análise , Volatilização
13.
Scand J Caring Sci ; 29(3): 486-94, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25250901

RESUMO

To date, research delving into the narratives of persons living with dementia is limited. Taking part in usual mealtime activities such as preparing food can sustain the identity of persons living with dementia. Yet if capacity for mealtime activities changes, this can put a strain or demand on the family, which must adjust and adapt to these changes. The aim of this study was to develop an in-depth story of resilience in one family living with dementia that was experiencing mealtime changes. Thematic narrative analysis following the elements of Clandinin and Connelly's (2000) 3D narrative inquiry space was used. One family's dementia journey was highlighted using the metaphor of a baking recipe to reflect their story of resilience. Developing positive strategies and continuing to learn and adapt were the two approaches used by this resilient family. Reminiscing, incorporating humour, having hope and optimism, and establishing social support were specific strategies. This family continued to learn and adapt by focusing on their positive gains and personal growth, accumulating life experiences, and balancing past pleasures while adapting to the new normal. Future work needs to further conceptualise resilience and how it can be supported in families living with dementia.


Assuntos
Demência/psicologia , Refeições/psicologia , Núcleo Familiar/psicologia , Resiliência Psicológica , Atividades Cotidianas/psicologia , Comunicação , Feminino , Esperança , Humanos , Relações Interpessoais , Aprendizagem , Memória Episódica , Relações Mãe-Filho/psicologia , Mães/psicologia , Narração , Otimismo/psicologia , Apoio Social , Senso de Humor e Humor como Assunto
14.
J Am Chem Soc ; 136(48): 16792-9, 2014 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-25406716

RESUMO

The mechanistic details of many polyketide synthases (PKSs) remain elusive due to the instability of transient intermediates that are not accessible via conventional methods. Here we report an atom replacement strategy that enables the rapid preparation of polyketone surrogates by selective atom replacement, thereby providing key substrate mimetics for detailed mechanistic evaluations. Polyketone mimetics are positioned on the actinorhodin acyl carrier protein (actACP) to probe the underpinnings of substrate association upon nascent chain elongation and processivity. Protein NMR is used to visualize substrate interaction with the actACP, where a tetraketide substrate is shown not to bind within the protein, while heptaketide and octaketide substrates show strong association between helix II and IV. To examine the later cyclization stages, we extended this strategy to prepare stabilized cyclic intermediates and evaluate their binding by the actACP. Elongated monocyclic mimics show much longer residence time within actACP than shortened analogs. Taken together, these observations suggest ACP-substrate association occurs both before and after ketoreductase action upon the fully elongated polyketone, indicating a key role played by the ACP within PKS timing and processivity. These atom replacement mimetics offer new tools to study protein and substrate interactions and are applicable to a wide variety of PKSs.


Assuntos
Cetonas/metabolismo , Policetídeo Sintases/química , Cetonas/química , Modelos Moleculares , Conformação Molecular , Policetídeo Sintases/metabolismo
15.
J Comput Aided Mol Des ; 28(11): 1143-51, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25168706

RESUMO

Peroxisome proliferator-activated receptor-gamma (PPARγ) plays a critical role in lipid and glucose homeostasis. It is the target of many drug discovery studies, because of its role in various disease states including diabetes and cancer. Thiazolidinediones, a synthetic class of agents that work by activation of PPARγ, have been used extensively as insulin-sensitizers for the management of type 2 diabetes. In this study, a combination of QSAR and docking methods were utilised to perform virtual screening of more than 25 million compounds in the ZINC library. The QSAR model was developed using 1,517 compounds and it identified 42,378 potential PPARγ agonists from the ZINC library, and 10,000 of these were selected for docking with PPARγ based on their diversity. Several steps were used to refine the docking results, and finally 30 potentially highly active ligands were identified. Four compounds were subsequently tested for their in vitro activity, and one compound was found to have a K i values of <5 µM.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Descoberta de Drogas , PPAR gama/agonistas , Tiazolidinedionas/administração & dosagem , Sítios de Ligação , Diabetes Mellitus Tipo 2/patologia , Humanos , Ligantes , Modelos Moleculares , Simulação de Acoplamento Molecular , PPAR gama/química , Receptores Ativados por Proliferador de Peroxissomo/química , Ligação Proteica , Relação Quantitativa Estrutura-Atividade
16.
Environ Sci Technol ; 48(15): 8807-14, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24943117

RESUMO

Human biomonitoring studies have shown that concentrations of perfluorooctane sulfonic acid (PFOS) in men are higher than in women. We investigate sex differences in elimination of PFOS by fitting a population-based pharmacokinetic model to six cross-sectional data sets from 1999 to 2012 from the US National Health and Nutrition Examination Survey (NHANES) and derive human first-order elimination rate constants (kE) and corresponding elimination half-lives (t1/2) for PFOS, where t1/2 = ln 2/kE. We use a modified version of the Ritter population-based pharmacokinetic model and derive elimination rate constants separately for men and women. The model accounts for population-average lifetime changes in PFOS intake, body weight, and menstruation rate. We compare the model-derived elimination rate constant for hypothetical nonmenstruating women to the elimination rate constant for men and women when menstruation is included as a loss process to evaluate the hypothesis that loss of PFOS by menstruation is an important process for women. The modeled elimination half-life for men is 4.7 years, and the modeled elimination half-life for women when excluding losses from menstruation is 3.7 years. The elimination half-life for women when menstruation is included in the model is 4.0 years. Thus, menstruation accounts for 30% of the discrepancy in elimination of PFOS between men and women. The remaining discrepancy is likely due to other sex-specific elimination routes that are not considered in our modeling.


Assuntos
Ácidos Alcanossulfônicos/farmacocinética , Poluentes Ambientais/farmacocinética , Fluorocarbonos/farmacocinética , Menstruação , Modelos Teóricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Peso Corporal , Criança , Estudos Transversais , Monitoramento Ambiental , Feminino , Meia-Vida , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Caracteres Sexuais , Adulto Jovem
17.
J Immunol ; 188(8): 4065-80, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22430738

RESUMO

During inflammation, accumulation of immune cells in activated lymph nodes (LNs), coupled with a transient shutdown in lymphocyte exit, results in dramatic cellular expansion. Counter-regulatory measures to restrain LN expansion must exist and may include re-establishment of lymphocyte egress to steady-state levels. Indeed, we show in a murine model that egress of lymphocytes from LNs was returned to steady-state levels during prolonged inflammation following initial retention. This restoration in lymphocyte egress was supported by a preferential expansion of cortical and medullary sinuses during late inflammation. Cortical and medullary sinus remodeling during late inflammation was dependent on temporal and spatial changes in vascular endothelial growth factor-A distribution. Specifically, its expression was restricted to the subcapsular space of the LN during early inflammation, whereas its expression was concentrated in the paracortical and medullary regions of the LN at later stages. We next showed that this process was mostly driven by the synergistic cross-talk between fibroblastic reticular cells and interstitial flow. Our data shed new light on the biological significance of LN lymphangiogenesis during prolonged inflammation and further underscore the collaborative roles of stromal cells, immune cells, and interstitial flow in modulating LN plasticity and function.


Assuntos
Linfonodos/imunologia , Linfócitos/imunologia , Transferência Adotiva , Animais , Anticorpos Neutralizantes/farmacologia , Comunicação Celular , Movimento Celular , Proliferação de Células , Células Endoteliais/imunologia , Células Endoteliais/patologia , Feminino , Hipertrofia , Inflamação/imunologia , Inflamação/patologia , Injeções Intraperitoneais , Linfonodos/patologia , Linfangiogênese , Linfócitos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Estromais/imunologia , Células Estromais/patologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
Cancer Res Commun ; 4(6): 1410-1429, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38717140

RESUMO

Encouraged by the observations of significant B7-H3 protein overexpression in many human solid tumors compared to healthy tissues, we directed our focus towards targeting B7-H3 using chimeric antigen receptor (CAR) T cells. We utilized a nanobody as the B7-H3-targeting domain in our CAR construct to circumvent the stability issues associated with single-chain variable fragment-based domains. In efforts to expand patient access to CAR T-cell therapy, we engineered our nanobody-based CAR into human Epstein-Barr virus-specific T cells (EBVST), offering a readily available off-the-shelf treatment. B7H3.CAR-armored EBVSTs demonstrated potent in vitro and in vivo activities against multiple B7-H3-positive human tumor cell lines and patient-derived xenograft models. Murine T cells expressing a murine equivalent of our B7H3.CAR exhibited no life-threatening toxicities in immunocompetent mice bearing syngeneic tumors. Further in vitro evaluation revealed that while human T, B, and natural killer cells were unaffected by B7H3.CAR EBVSTs, monocytes were targeted because of upregulation of B7-H3. Such targeting of myeloid cells, which are key mediators of cytokine release syndrome (CRS), contributed to a low incidence of CRS in humanized mice after B7H3.CAR EBVST treatment. Notably, we showed that B7H3.CAR EBVSTs can target B7-H3-expressing myeloid-derived suppressor cells (MDSC), thereby mitigating MDSC-driven immune suppression. In summary, our data demonstrate that our nanobody-based B7H3.CAR EBVSTs are effective as an off-the-shelf therapy for B7-H3-positive solid tumors. These cells also offer an avenue to modulate the immunosuppressive tumor microenvironment, highlighting their promising clinical potential in targeting solid tumors. SIGNIFICANCE: Clinical application of EBVSTs armored with B7-H3-targeting CARs offer an attractive solution to translate off-the-shelf CAR T cells as therapy for solid tumors.


Assuntos
Antígenos B7 , Herpesvirus Humano 4 , Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Linfócitos T , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Humanos , Antígenos B7/imunologia , Antígenos B7/metabolismo , Camundongos , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Herpesvirus Humano 4/imunologia , Imunoterapia Adotiva/métodos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linhagem Celular Tumoral , Neoplasias/terapia , Neoplasias/imunologia , Feminino , Anticorpos de Domínio Único/imunologia
19.
BMC Geriatr ; 13: 59, 2013 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-23758824

RESUMO

BACKGROUND: Patients with chronic diseases often undertake multiple medication regimes to manage their condition, prevent complications and to maintain their quality of life. A patient's medication knowledge has been defined as the awareness of drug name, purpose, administration schedule, adverse effects or side-effects and special administration instructions. Poor medication knowledge can have a negative impact on medication adherence and patient safety and, in increasing the use of medical resources. The objective of the study is to assess the medication knowledge of elderly patients with chronic disease conditions and the factors affecting this knowledge. METHODS: A cross-sectional survey was conducted in patients aged ≥ 60 with chronic disease conditions or their caregivers were recruited from two general outpatient clinics and two medical outpatient clinics in the public sector. Participants were approached by trained interviewers to complete a semi-structured questionnaire to assess their understanding of the instructions and information relating to their regular medications, which included medication name, regimen, purpose and common side-effects and precautions. RESULTS: A total of 412 patients were recruited with the mean age of 72.86 ± 7.70. Of those, 221 (54.2%) were male and 226 (55.4%) were of primary school educational level or below. The mean number of medications taken per patient was 3.75 ± 1.93. Overall, 52.7% of patients felt that healthcare staff or clinic pharmacists had very clearly explained the administration instruction of the prescribed medications whilst 47.9% had very clear explanations of drug purpose but only 11.4% felt they had very clear explanations of side-effects. 396 patients (96.1%) failed to recall any side effects or precautions of each of their prescribed medications, although 232 patients (58.4%) would consult a doctor if they encountered problems with their medications. Logistic regression analysis showed that for every additional medication prescribed, the likeliness of patients to recall side-effects of all the medications prescribed was significantly lowered by 35% (OR = 0.65; 95% CI = 0.44-0.94; P = 0.023). In addition, those who finished secondary school or higher education were likely to possess more knowledge of side-effects (OR = 9.88; 95% CI = 2.11-46.25; P = 0.004). CONCLUSIONS: Patients who take medications for their chronic diseases generally lack knowledge on side-effects of their medications which could potentially affect medication compliance and medication safety.


Assuntos
Doença Crônica/epidemiologia , Doença Crônica/terapia , Conhecimentos, Atitudes e Prática em Saúde , Adesão à Medicação , Preparações Farmacêuticas , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Assistência ao Paciente/métodos
20.
Eur J Neurosci ; 36(10): 3314-21, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22845723

RESUMO

Somatic sensory neuron somata are located within the dorsal root ganglia (DRG) and are mostly ensheathed by individual satellite glial cell sheets. It has been noted, however, that a subpopulation of these DRG somata are intimately associated, separated only by a single thin satellite glial cell membrane septum. We set out to test whether such neuron-glial cell-neuron trimers (NGlNs) are also linked functionally. The presence of NGlNs in chick DRGs was confirmed by electron microscopy. Selective satellite glial cell immunostains were identified and were used to image the inter-neuron septa in DRG frozen sections. We used a gentle, dispase-based enzymatic method to isolate chick and rat NGlNs in vitro for double patch clamp recordings. In the majority of pairs tested, an action potential-like stimulus train delivered to one soma resulted in a delayed, noisy and long-duration response in its idle partner. The response to a second stimulus train given minutes later was markedly facilitated. Both bidirectional and unidirectional transmission was observed between the paired neurons. Transmission was chemical and block by the general purinergic blocker suramin implicated ATP as a neurotransmitter. We conclude that the two neuronal somata in the NGlN can communicate by chemical transmission, which may involve a transglial, bi-synaptic pathway. This novel soma-to-soma transmission reflects a novel form of processing that may play a role in sensory disorders in the DRG and interneuron communication in the central nervous system.


Assuntos
Gânglios Espinais/fisiologia , Células Receptoras Sensoriais/fisiologia , Transmissão Sináptica/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Embrião de Galinha , Neuroglia/citologia , Neuroglia/fisiologia , Antagonistas Purinérgicos/farmacologia , Ratos , Células Receptoras Sensoriais/citologia , Suramina/farmacologia , Sinapses/metabolismo , Transmissão Sináptica/efeitos dos fármacos
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