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1.
Bioinformatics ; 40(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38991828

RESUMO

MOTIVATION: Sanger sequencing of taxonomic marker genes (e.g. 16S/18S/ITS/rpoB/cpn60) represents the leading method for identifying a wide range of microorganisms including bacteria, archaea, and fungi. However, the manual processing of sequence data and limitations associated with conventional BLAST searches impede the efficient generation of strain libraries essential for cataloging microbial diversity and discovering novel species. RESULTS: isolateR addresses these challenges by implementing a standardized and scalable three-step pipeline that includes: (1) automated batch processing of Sanger sequence files, (2) taxonomic classification via global alignment to type strain databases in accordance with the latest international nomenclature standards, and (3) straightforward creation of strain libraries and handling of clonal isolates, with the ability to set customizable sequence dereplication thresholds and combine data from multiple sequencing runs into a single library. The tool's user-friendly design also features interactive HTML outputs that simplify data exploration and analysis. Additionally, in silico benchmarking done on two comprehensive human gut genome catalogues (IMGG and Hadza hunter-gather populations) showcase the proficiency of isolateR in uncovering and cataloging the nuanced spectrum of microbial diversity, advocating for a more targeted and granular exploration within individual hosts to achieve the highest strain-level resolution possible when generating culture collections. AVAILABILITY AND IMPLEMENTATION: isolateR is available at: https://github.com/bdaisley/isolateR.


Assuntos
Bactérias , Software , Bactérias/genética , Bactérias/classificação , Análise de Sequência de DNA/métodos , Humanos , Archaea/genética , Fungos/genética , Biblioteca Gênica
3.
Risk Anal ; 41(10): 1795-1808, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33586801

RESUMO

This article develops a dynamic extension of the classic model of cybersecurity investment formulated by Gordon and Loeb. In this dynamic model, results are influenced by the rate at which cybersecurity assets depreciate and the rate of return on investment. Depreciation costs are lower in the dynamic model than is implicitly assumed in the classic model, while the rate-of-return threshold is higher. On balance, the user cost of cybersecurity assets is lower in the dynamic model than is implicitly assumed in the classic model. This difference increases the economically efficient size of the cybersecurity system in value terms, increasing the efficient level of risk reduction.

4.
Am J Physiol Renal Physiol ; 319(1): F8-F18, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32421349

RESUMO

Sepsis is the leading cause of acute kidney injury in critically ill patients. Tumor necrosis factor-α (TNF-α) has been implicated in the pathogenesis of septic kidney injury; however, the sites and mechanisms of renal TNF-α production during sepsis remain to be defined. In the present study, we showed that TNF-α expression is increased in medullary thick ascending limbs (MTALs) of mice with sepsis induced by cecal ligation and puncture. Treatment with lipopolysaccharide (LPS) for 3 h in vitro also increased MTAL TNF-α production. Sepsis and LPS increased MTAL TNF-α expression through activation of the myeloid differentiation factor 88 (MyD88)-IL-1 receptor-associated kinase 1-ERK signaling pathway. Pretreatment with monophosphoryl lipid A (MPLA), a nontoxic immunomodulator that protects against bacterial infection, eliminated the sepsis- and LPS-induced increases in MTAL TNF-α production. The suppressive effect of MPLA on TNF-α was mediated through activation of a phosphatidylinositol 3-kinase-dependent pathway that inhibits MyD88-dependent ERK activation. This likely involves MPLA-phosphatidylinositol 3-kinase-mediated induction of Tollip, which negatively regulates the MyD88-ERK pathway by inhibiting activation of IL-1 receptor-associated kinase 1. These regulatory mechanisms are similar to those previously shown to mediate the effect of MPLA to prevent sepsis-induced inhibition of MTAL [Formula: see text] absorption. These results identify the MTAL as a site of local TNF-α production in the kidney during sepsis and identify molecular mechanisms that can be targeted to attenuate renal TNF-α expression. The ability of MPLA pretreatment to suppress MyD88-dependent ERK signaling in the MTAL during sepsis has the dual beneficial effects of protecting tubule transport functions and attenuating harmful proinflammatory responses.


Assuntos
Citocinas/metabolismo , Medula Renal/efeitos dos fármacos , Lipídeo A/análogos & derivados , Alça do Néfron/efeitos dos fármacos , Sepse/metabolismo , Animais , Medula Renal/metabolismo , Lipídeo A/farmacologia , Lipopolissacarídeos/farmacologia , Alça do Néfron/metabolismo , Masculino , Camundongos , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Transdução de Sinais/efeitos dos fármacos
5.
Exp Brain Res ; 238(12): 2733-2744, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32970199

RESUMO

Previous research has demonstrated hemisphere-specific motor deficits in ipsilesional and contralesional unimanual movements in patients with hemiparetic stroke due to MCA infarct. Due to the importance of bilateral motor actions on activities of daily living, we now examine how bilateral coordination may be differentially affected by right or left hemisphere stroke. To avoid the caveat of simply adding unimanual deficits in assessing bimanual coordination, we designed a unique task that requires spatiotemporal coordination features that do not exist in unimanual movements. Participants with unilateral left (LHD) or right hemisphere damage (RHD) and age-matched controls moved a virtual rectangle (bar) from a midline start position to a midline target. Movement along the long axis of the bar was redundant to the task, such that the bar remained in the center of and parallel to an imaginary line connecting each hand. Thus, to maintain midline position of the bar, movements of one hand closer to or further away from the bar midline required simultaneous, but oppositely directed displacements with the other hand. Our findings indicate that left (LHD), but not right (RHD) hemisphere-damaged patients showed poor interlimb coordination, reflected by significantly lower correlations between displacements of each hand along the bar axis. These left hemisphere-specific deficits were only apparent prior to peak velocity, likely reflecting predictive control of interlimb coordination. In contrast, the RHD group bilateral coordination was not significantly different than that of the control group. We conclude that predictive mechanisms that govern bilateral coordination are dependent on left hemisphere mechanisms. These findings indicate that assessment and training in cooperative bimanual tasks should be considered as part of an intervention framework for post-stroke physical rehabilitation.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Atividades Cotidianas , Lateralidade Funcional , Mãos , Humanos , Movimento , Desempenho Psicomotor , Acidente Vascular Cerebral/complicações
6.
Am J Physiol Renal Physiol ; 317(3): F705-F719, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31241993

RESUMO

LPS inhibits HCO3- absorption in the medullary thick ascending limb (MTAL) through a Toll-like receptor 4 (TLR4)-myeloid differentiation factor 88 (MyD88)-extracellular signal-regulated kinase (ERK) pathway that is upregulated by sepsis. Pretreatment with the nontoxic immunomodulator monophosphoryl lipid A (MPLA) prevents inhibition by LPS through activation of a TLR4-TIR-domain-containing adaptor-inducing interferon-ß (TRIF)-phosphatidylinositol 3-kinase (PI3K) pathway that prevents LPS-induced ERK activation. Here, we identified the molecular mechanisms that underlie the protective inhibitory interaction between the MPLA-PI3K and LPS-ERK pathways. Treatment of mouse MTALs with LPS in vitro increased phosphorylation of IL-1 receptor-associated kinase (IRAK)-1, a critical mediator of LPS signaling downstream of TLR4-MyD88. Activation of ERK by LPS was eliminated by a selective IRAK-1 inhibitor, establishing IRAK-1 as the upstream mediator of ERK activation. Pretreatment of MTALs with MPLA in vitro prevented LPS-induced IRAK-1 activation; this effect was dependent on PI3K. Treatment of MTALs with MPLA increased expression of Toll-interacting protein (Tollip), an inducible protein that negatively regulates LPS signaling by inhibiting IRAK-1. The MPLA-induced increase in Tollip protein level was prevented by PI3K inhibitors. In coimmunoprecipitation experiments, MPLA increased the amount of Tollip stably bound to IRAK-1, an interaction that inhibits IRAK-1 activation. These results support a mechanism whereby MPLA increases Tollip expression in the MTAL through a PI3K-dependent pathway. Tollip, in turn, inhibits LPS-induced TLR4 signaling by suppressing activation of IRAK-1, thereby preventing activation of ERK that inhibits HCO3- absorption. These studies show that MPLA induces reprogramming of MTAL cells that protects against LPS stimulation and identify IRAK-1 and Tollip as new therapeutic targets to prevent renal tubule dysfunction in response to infectious and inflammatory stimuli.


Assuntos
Adjuvantes Imunológicos/farmacologia , Bicarbonatos/metabolismo , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipídeo A/análogos & derivados , Alça do Néfron/efeitos dos fármacos , Reabsorção Renal/efeitos dos fármacos , Sepse/tratamento farmacológico , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Citoproteção , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Lipídeo A/farmacologia , Alça do Néfron/metabolismo , Alça do Néfron/fisiopatologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosforilação , Ratos Sprague-Dawley , Sepse/metabolismo , Sepse/fisiopatologia , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
7.
Pharm Res ; 36(12): 164, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31637544

RESUMO

PURPOSE: To describe a stepwise approach to evaluate the pH effect for a weakly basic drug by in vitro, in vivo and in silico techniques and identify a viable mitigation strategy that addresses the risk. METHODS: Clinical studies included assessment of the pH effect with famotidine. In vitro dissolution was evaluated in various biorelevant media and in a pH-shift test. PK studies in dogs were conducted under pentagastrin or famotidine pre-treatment and GastroPlus was employed to model human and dog PK data and simulate the performance in human. RESULTS: Clinical data indicated considerable pH dependent absorption of the drug when dosed in the presence of H2-antagonists. In vitro dissolution and in vivo dog data confirmed that the observed pH effect was due to reduced dissolution rate and lower solubility at increased gastric and intestinal pH. A salt form was identified to overcome the effect by providing fast dissolution and prolonged supersaturation. GastroPlus simulations predicted a mitigation of the pH effect by the salt. CONCLUSIONS: The drug exhibited a strong pH-effect in humans. The in vitro, in vivo and modeling approach provides a systematic workflow to evaluate the risk of a new drug and identify a strategy able to mitigate the risk.


Assuntos
Antiulcerosos/farmacocinética , Simulação por Computador , Composição de Medicamentos/métodos , Famotidina/farmacocinética , Absorção Intestinal , Modelos Biológicos , Administração Oral , Animais , Antiulcerosos/administração & dosagem , Disponibilidade Biológica , Cães , Famotidina/administração & dosagem , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino
8.
Twin Res Hum Genet ; 22(2): 79-87, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31012404

RESUMO

Type 2 diabetes (T2D) is a chronic disease that disproportionately affects Indigenous Australians. We have previously reported the localization of a novel T2D locus by linkage analysis to chromosome 2q24 in a large admixed Indigenous Australian pedigree (Busfield et al. (2002). American Journal of Human Genetics, 70, 349-357). Here we describe fine mapping of this region in this pedigree, with the identification of SNPs showing strong association with T2D: rs3845724 (diabetes p = 7 × 10-4), rs4668106 (diabetes p = 9 × 10-4) and rs529002 (plasma glucose p = 3 × 10-4). These associations were successfully replicated in an independent collection of Indigenous Australian T2D cases and controls. These SNPs all lie within the gene encoding ceramide synthase 6 (CERS6) and thus may regulate ceramide synthesis.


Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Proteínas de Membrana/genética , Esfingosina N-Aciltransferase/genética , Austrália/epidemiologia , Diabetes Mellitus Tipo 2/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Polimorfismo de Nucleotídeo Único/genética
9.
Int J Mol Sci ; 20(14)2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31373300

RESUMO

Although cancer is a leading cause of death, significant breakthroughs have been made in its treatment in recent years. In particular, increasingly effective cancer vaccines are being developed, including some for colorectal cancer. There are also currently a variety of compounds that can act as adjuvants, such as signalling molecules called cytokines. Other adjuvants target and inhibit the specific mechanisms by which cancers evade the immune system. One of them is a galectin inhibitor, which targets galectins-proteins produced by cancer cells that can cause the death of immune cells. Likewise, immune checkpoint inhibitors affect immune checkpoints-natural host proteins that usually control inflammation but can be exploited by cancers to weaken the body's defences. Equally, regulatory T cells may contribute to the progression of cancer by inhibiting the functions of other T cells. The main advantages of cancer vaccines include their low toxicity and their ability to strengthen the immune system. Nevertheless, significant limitations include their slow effects and their inability to treat cancer at times due to immunosuppression. Ultimately, ongoing trials provide hope for the development of more effective methods of immunotherapeutic inoculation that can target a greater variety of cancers.


Assuntos
Vacinas Anticâncer/imunologia , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/terapia , Citocinas/imunologia , Galectinas/antagonistas & inibidores , Linfócitos T Reguladores/imunologia , Adjuvantes Imunológicos , Humanos , Imunoterapia/métodos , Evasão Tumoral/imunologia
10.
Am J Physiol Renal Physiol ; 315(3): F711-F725, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29741098

RESUMO

Metabolic acidosis is the most common acid-base disorder in septic patients and is associated with increased mortality. Previously, we demonstrated that sepsis induced by cecal ligation and puncture (CLP) impairs [Formula: see text] absorption in the medullary thick ascending limb (MTAL) by 1) decreasing the intrinsic [Formula: see text] absorptive capacity and 2) enhancing inhibition of [Formula: see text] absorption by LPS through upregulation of Toll-like receptor (TLR) 4 signaling. Both effects depend on ERK activation. Monophosphoryl lipid A (MPLA) is a detoxified TLR4 agonist that enhances innate antimicrobial immunity and improves survival following sepsis. Pretreatment of MTALs with MPLA in vitro prevents LPS inhibition of [Formula: see text] absorption. Here we examined whether pretreatment with MPLA would protect the MTAL against sepsis. Vehicle or MPLA was administered to mice 48 h before sham or CLP surgery, and MTALs were studied in vitro 18 h postsurgery. Pretreatment with MPLA prevented the effects of sepsis to decrease the basal [Formula: see text] absorption rate and enhance inhibition by LPS. These protective effects were mediated through MPLA stimulation of a Toll/IL-1 receptor domain-containing adaptor-inducing IFN-ß-(TRIF)-dependent phosphatidylinositol 3-kinase-Akt pathway that prevents sepsis- and LPS-induced ERK activation. The effects of MPLA to improve MTAL [Formula: see text] absorption were associated with marked improvement in plasma [Formula: see text] concentration, supporting a role for the kidneys in the pathogenesis of sepsis-induced metabolic acidosis. These studies support detoxified TLR4-based immunomodulators, such as MPLA, that enhance antimicrobial responses as a safe and effective approach to prevent or treat sepsis-induced renal tubule dysfunction and identify cell signaling pathways that can be targeted to preserve MTAL [Formula: see text] absorption and attenuate metabolic acidosis during sepsis.


Assuntos
Acidose/prevenção & controle , Bicarbonatos/metabolismo , Lipídeo A/análogos & derivados , Alça do Néfron/efeitos dos fármacos , Reabsorção Renal/efeitos dos fármacos , Sepse/tratamento farmacológico , Equilíbrio Ácido-Base/efeitos dos fármacos , Acidose/metabolismo , Acidose/fisiopatologia , Proteínas Adaptadoras de Transporte Vesicular/deficiência , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Bicarbonatos/sangue , Bicarbonatos/urina , Modelos Animais de Doenças , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Lipídeo A/farmacologia , Alça do Néfron/metabolismo , Alça do Néfron/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sepse/metabolismo , Sepse/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/agonistas
11.
Haematologica ; 103(2): 288-296, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29097500

RESUMO

The objective of this study was to create a bioclinical model, based on clinical and molecular predictors of event-free and overall survival for relapsed/refractory diffuse large B-cell lymphoma patients treated on the Canadian Cancer Trials Group (CCTG) LY12 prospective study. In 91 cases, sufficient histologic material was available to create tissue microarrays and perform immunohistochemistry staining for CD10, BCL6, MUM1/IRF4, FOXP1, LMO2, BCL2, MYC, P53 and phosphoSTAT3 (pySTAT3) expression. Sixty-seven cases had material sufficient for fluorescent in situ hybridization (FISH) for MYC and BCL2 In addition, 97 formalin-fixed, paraffin-embedded tissue samples underwent digital gene expression profiling (GEP) to evaluate BCL2, MYC, P53, and STAT3 expression, and to determine cell-of-origin (COO) using the Lymph2Cx assay. No method of determining COO predicted event-free survival (EFS) or overall survival (OS). Factors independently associated with survival outcomes in multivariate analysis included primary refractory disease, elevated serum lactate dehydrogenase (LDH) at relapse, and MYC or BCL2 protein or gene expression. A bioclinical score using these four factors predicted outcome with 3-year EFS for cases with 0-1 vs 2-4 factors of 55% vs 16% (P<0.0001), respectively, assessing MYC and BCL2 by immunohistochemistry, 46% vs. 5% (P<0.0001) assessing MYC and BCL2 messenger ribonucleic acid (mRNA) by digital gene expression, and 42% vs 21% (P=0.079) assessing MYC and BCL2 by FISH. This proposed bioclinical model should be further studied and validated in other datasets, but may discriminate relapsed/refractory diffuse large B-cell lymphoma (DLBCL) patients who could benefit from conventional salvage therapy from others who require novel approaches. The LY12 study; clinicaltrials.gov Identifier: 00078949.


Assuntos
Linfoma Difuso de Grandes Células B/diagnóstico , Modelos Biológicos , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-myc/análise , Adulto , Idoso , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Terapia de Salvação/métodos , Adulto Jovem
13.
J Cell Biochem ; 118(5): 979-993, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27291138

RESUMO

Recent evidences show that activation of serotonin 2A receptors (5-HT2A R) by agonists is significant in improving therapeutic activity of disease conditions, such as obsessive-compulsive disorder (OCD). Though the exact molecular mechanism is still not well understood, it is thought to involve agonist-driven, enhanced expression of 5-HT2A R in certain areas of brain, such as the pre-frontal cortex (PFC). Several other reports have also demonstrated association of OCD with lower dopamine receptor (D2 R) availability, primarily in the striatum of the brain along with dysfunction of 5-HT2A R-D2 R heteromer regulation. We thus hypothesized that compound(s) interacting with this molecular mechanism could be developed as drugs for long-term beneficial effects against OCD. In the present study, we have obtained experimental evidence in cultured neuronal cells (CLU213) that aqueous extract (AE, 50 µg/mL, P < 0.05) of the Australian cane toad skin significantly increased the levels of 5-HT2A R and D2 R protein and mRNA expression. AE was also found to enhance the interaction between 5-HT2A R and D2 R and formation of expression of 5-HT2A R-D2 R heteromer using co-immunoprecipitation and Western blot. Further investigation showed the involvement of classical signaling pathway (Gq/11 -PLCß) along with c-FOS transcription factor preferentially in 5-HT2A -mediated agonist activation. These results obtained demonstrated that AE upregulates 5-HT2A R by a mechanism that appears to involve Gq/11 -PLCß signaling pathway and c-FOS transcription factor activation. We indicate this enhanced 5-HT2A R and D2 R expression and their interaction to induce increased 5-HT2A R-D2 R heteromer formation by exposure to AE might provide a molecular mechanism to develop potential novel drug candidates to ameliorate OCD symptoms. J. Cell. Biochem. 118: 979-993, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Anuros/metabolismo , Neurônios/efeitos dos fármacos , Receptor 5-HT2A de Serotonina/metabolismo , Receptores de Dopamina D2/metabolismo , Pele/química , Extratos de Tecidos/farmacologia , Animais , Linhagem Celular , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Neurônios/citologia , Neurônios/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas c-fos/genética , Ratos , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional , Regulação para Cima
14.
Am J Physiol Renal Physiol ; 313(1): F103-F115, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28356284

RESUMO

Monophosphoryl lipid A (MPLA) is a detoxified derivative of LPS that induces tolerance to LPS and augments host resistance to bacterial infections. Previously, we demonstrated that LPS inhibits [Formula: see text] absorption in the medullary thick ascending limb (MTAL) through a basolateral Toll-like receptor 4 (TLR4)-myeloid differentiation factor 88 (MyD88)-ERK pathway. Here we examined whether pretreatment with MPLA would attenuate LPS inhibition. MTALs from rats were perfused in vitro with MPLA (1 µg/ml) in bath and lumen or bath alone for 2 h, and then LPS was added to (and MPLA removed from) the bath solution. Pretreatment with MPLA eliminated LPS-induced inhibition of [Formula: see text] absorption. In MTALs pretreated with MPLA plus a phosphatidylinositol 3-kinase (PI3K) or Akt inhibitor, LPS decreased [Formula: see text] absorption. MPLA increased Akt phosphorylation in dissected MTALs. The Akt activation was eliminated by a PI3K inhibitor and in MTALs from TLR4-/- or Toll/IL-1 receptor domain-containing adaptor-inducing IFN-ß (TRIF)-/- mice. The effect of MPLA to prevent LPS inhibition of [Formula: see text] absorption also was TRIF dependent. Pretreatment with MPLA prevented LPS-induced ERK activation; this effect was dependent on PI3K. MPLA alone had no effect on [Formula: see text] absorption, and MPLA pretreatment did not prevent ERK-mediated inhibition of [Formula: see text] absorption by aldosterone, consistent with MPLA's low toxicity profile. These results demonstrate that pretreatment with MPLA prevents the effect of LPS to inhibit [Formula: see text] absorption in the MTAL. This protective effect is mediated directly through MPLA stimulation of a TLR4-TRIF-PI3K-Akt pathway that prevents LPS-induced ERK activation. These studies identify detoxified TLR4-based immunomodulators as novel potential therapeutic agents to prevent or treat renal tubule dysfunction in response to bacterial infections.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Lipídeo A/análogos & derivados , Lipopolissacarídeos/toxicidade , Alça do Néfron/efeitos dos fármacos , Fosfatidilinositol 3-Quinase/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos , Proteínas Adaptadoras de Transporte Vesicular/deficiência , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Bicarbonatos/metabolismo , Citoproteção , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Técnicas In Vitro , Lipídeo A/farmacologia , Alça do Néfron/enzimologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Perfusão , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Reabsorção Renal/efeitos dos fármacos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
15.
Adv Health Sci Educ Theory Pract ; 22(2): 401-413, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28181019

RESUMO

Although there is extensive evidence confirming the predictive validity of situational judgement tests (SJTs) in medical education, there remains a shortage of evidence for their predictive validity for performance of postgraduate trainees in their first role in clinical practice. Moreover, to date few researchers have empirically examined the complementary roles of academic and non-academic selection methods in predicting in-role performance. This is an important area of enquiry as despite it being common practice to use both types of methods within a selection system, there is currently no evidence that this approach translates into increased predictive validity of the selection system as a whole, over that achieved by the use of a single selection method. In this preliminary study, the majority of the range of scores achieved by successful applicants to the UK Foundation Programme provided a unique opportunity to address both of these areas of enquiry. Sampling targeted high (>80th percentile) and low (<20th percentile) scorers on the SJT. Supervisors rated 391 trainees' in-role performance, and incidence of remedial action was collected. SJT and academic performance scores correlated with supervisor ratings (r = .31 and .28, respectively). The relationship was stronger between the SJT and in-role performance for the low scoring group (r = .33, high scoring group r = .11), and between academic performance and in-role performance for the high scoring group (r = .29, low scoring group r = .11). Trainees with low SJT scores were almost five times more likely to receive remedial action. Results indicate that an SJT for entry into trainee physicians' first role in clinical practice has good predictive validity of supervisor-rated performance and incidence of remedial action. In addition, an SJT and a measure of academic performance appeared to be complementary to each other. These initial findings suggest that SJTs may be more predictive at the lower end of a scoring distribution, and academic attainment more predictive at the higher end.


Assuntos
Logro , Competência Clínica , Educação de Pós-Graduação em Medicina/estatística & dados numéricos , Critérios de Admissão Escolar/estatística & dados numéricos , Adulto , Avaliação Educacional , Feminino , Humanos , Julgamento , Masculino , Valor Preditivo dos Testes , Grupos Raciais , Reprodutibilidade dos Testes , Reino Unido
16.
Am J Physiol Renal Physiol ; 311(3): F600-13, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27358052

RESUMO

High-mobility group box 1 (HMGB1) is a nuclear protein released extracellularly in response to infection or injury, where it activates immune responses and contributes to the pathogenesis of kidney dysfunction in sepsis and sterile inflammatory disorders. Recently, we demonstrated that HMGB1 inhibits HCO3 (-) absorption in perfused rat medullary thick ascending limbs (MTAL) through a basolateral receptor for advanced glycation end products (RAGE)-dependent pathway that is additive to Toll-like receptor 4 (TLR4)-ERK-mediated inhibition by LPS (Good DW, George T, Watts BA III. Am J Physiol Renal Physiol 309: F720-F730, 2015). Here, we examined signaling and transport mechanisms that mediate inhibition by HMGB1. Inhibition of HCO3 (-) absorption by HMGB1 was eliminated by the Rho-associated kinase (ROCK) inhibitor Y27632 and by a specific inhibitor of Rho, the major upstream activator of ROCK. HMGB1 increased RhoA and ROCK1 activity. HMGB1-induced ROCK1 activation was eliminated by the RAGE antagonist FPS-ZM1 and by inhibition of Rho. The Rho and ROCK inhibitors had no effect on inhibition of HCO3 (-) absorption by bath LPS. Inhibition of HCO3 (-) absorption by HMGB1 was eliminated by bath amiloride, 0 Na(+) bath, and the F-actin stabilizer jasplakinolide, three conditions that selectively prevent inhibition of MTAL HCO3 (-) absorption mediated through NHE1. HMGB1 decreased basolateral Na(+)/H(+) exchange activity through activation of ROCK. We conclude that HMGB1 inhibits HCO3 (-) absorption in the MTAL through a RAGE-RhoA-ROCK1 signaling pathway coupled to inhibition of NHE1. The HMGB1-RAGE-RhoA-ROCK1 pathway thus represents a potential target to attenuate MTAL dysfunction during sepsis and other inflammatory disorders. HMGB1 and LPS inhibit HCO3 (-) absorption through different receptor signaling and transport mechanisms, which enables these pathogenic mediators to act directly and independently to impair MTAL function.


Assuntos
Proteína HMGB1/metabolismo , Túbulos Renais/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Amidas/farmacologia , Amilorida/farmacologia , Animais , Bicarbonatos/metabolismo , Depsipeptídeos/farmacologia , Túbulos Renais/efeitos dos fármacos , Masculino , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
17.
Adv Exp Med Biol ; 957: 257-272, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28035570

RESUMO

Brain lateralization is a ubiquitous feature of neural organization across the vertebrate spectrum. We have developed a model of motor lateralization that attributes different motor control processes to each cerebral hemisphere. This bilateral hemispheric model of motor control has successfully predicted hemisphere-specific motor control and motor learning deficits in the ipsilesional, or non-paretic, arm of patients with unilateral stroke. We now show across large number and range of stroke patients that these motor performance deficits in the non-paretic arm of stroke patients vary with both the side of the lesion, as well as with the severity of contralesional impairment. This last point can be functionally devastating for patients with severe contralesional paresis because for these individuals, performance of upper extremity activities of daily living depends primarily and often exclusively on ipsilesional arm function. We present a pilot study focused on improving the speed and coordination of ipsilesional arm function in a convenience sample of three stroke patients with severe contralesional impairment. Over a three-week period, patients received a total of nine 1.5 h sessions of training that included intense practice of virtual reality and real-life tasks. Our results indicated substantial improvements in ipsilesional arm movement kinematics, functional performance, and that these improvements carried over to improve functional independence. In addition, the contralesional arm improved in our measure of contralesional impairment, which was likely due to improved participation in activities of daily living. We discuss of our findings for physical rehabilitation.


Assuntos
Lateralidade Funcional/fisiologia , Recuperação de Função Fisiológica/fisiologia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/fisiopatologia , Atividades Cotidianas , Idoso , Fenômenos Biomecânicos/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Resultado do Tratamento
18.
Am J Physiol Renal Physiol ; 309(8): F720-30, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26180239

RESUMO

High-mobility group box 1 (HMGB1) is a damage-associated molecule implicated in mediating kidney dysfunction in sepsis and sterile inflammatory disorders. HMGB1 is a nuclear protein released extracellularly in response to infection or injury, where it interacts with Toll-like receptor 4 (TLR4) and other receptors to mediate inflammation. Previously, we demonstrated that LPS inhibits HCO(3)(-) absorption in the medullary thick ascending limb (MTAL) through a basolateral TLR4-ERK pathway (Watts BA III, George T, Sherwood ER, Good DW. Am J Physiol Cell Physiol 301: C1296-C1306, 2011). Here, we examined whether HMGB1 could inhibit HCO(3)(-) absorption through the same pathway. Adding HMGB1 to the bath decreased HCO(3)(-) absorption by 24% in isolated, perfused rat and mouse MTALs. In contrast to LPS, inhibition by HMGB1 was preserved in MTALs from TLR4(-/-) mice and was unaffected by ERK inhibitors. Inhibition by HMGB1 was eliminated by the receptor for advanced glycation end products (RAGE) antagonist FPS-ZM1 and by neutralizing anti-RAGE antibody. Confocal immunofluorescence showed expression of RAGE in the basolateral membrane domain. Inhibition of HCO(3)(-) absorption by HMGB1 through RAGE was additive to inhibition by LPS through TLR4 and to inhibition by Gram-positive bacterial molecules through TLR2. Bath amiloride, which selectively prevents inhibition of MTAL HCO(3)(-) absorption mediated through Na⁺/H⁺ exchanger 1 (NHE1), eliminated inhibition by HMGB1. We conclude that HMGB1 inhibits MTAL HCO(3)(-) absorption through a RAGE-dependent pathway distinct from TLR4-mediated inhibition by LPS. These studies provide new evidence that HMGB1-RAGE signaling acts directly to impair the transport function of renal tubules. They reveal a novel paradigm for sepsis-induced renal tubule dysfunction, whereby exogenous pathogen-associated molecules and endogenous damage-associated molecules act directly and independently to inhibit MTAL HCO(3)(-) absorption through different receptor signaling pathways.


Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Proteína HMGB1/farmacologia , Medula Renal/metabolismo , Bicarbonato de Sódio/metabolismo , Animais , Benzamidas/farmacologia , Técnicas In Vitro , Medula Renal/efeitos dos fármacos , Túbulos Renais/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ratos , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/imunologia , Sepse/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
19.
Mol Pharm ; 12(12): 4434-44, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26536519

RESUMO

BMS-914392 is a tricyclic pyranoquinoline BCS class 2 weak base that demonstrates high solubility in low pH environments. Initial clinical studies indicated that rapid release of high dose BMS-914392 led to transient adverse events associated with peak plasma concentrations. A modified release (MR) formulation strategy was proposed to suppress the peak blood concentration and maintain total exposure to overcome the adverse effects. Three modified release prototype formulations were developed and tested via a USP 3 dissolution method to verify that each formulation can effectively slow the release of BMS-914392. A pharmacokinetic (PK) absorption model was employed to guide the formulation development and selection. Simulations showed good agreement with plasma levels measured after oral dosing in dogs. Identification of key formulation factors to achieve release rates suitable for blunting peak blood levels without diminishing exposure were achieved through combined preclinical data and use of GastroPlus simulations. PK absorption model refinements based on phase 1 data, dog pharmacokinetic results, and in vitro data provided reliable predictions of human absorption profiles and variability in patients. All three prototype formulations demonstrated lower maximum plasma concentrations of BMS-914392 and maintained satisfactory relative bioavailability. Both the PK absorption model and subsequent clinical data indicated that an acidified hydrophilic matrix MR formulation had the greatest potential to reduce the incidence of adverse events and showed the best exposure profile in fasted state healthy subjects with and without famotidine coadministration. The risk based development process achieved successful screening and selection of a suitable modified release formulation to enable clinical efficacy trials.


Assuntos
Quinolinas/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Química Farmacêutica/métodos , Simulação por Computador , Estudos Cross-Over , Cães , Famotidina/administração & dosagem , Humanos , Absorção Intestinal , Masculino , Modelos Biológicos , Quinolinas/administração & dosagem , Solubilidade
20.
Am J Dermatopathol ; 37(3): 232-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25374307

RESUMO

We describe the first reported occurrence of a composite cutaneous lymphoma involving a mantle cell lymphoma (MCL) and primary cutaneous anaplastic large cell lymphoma. The lesion occurred in a 76-year-old man with longstanding MCL who developed nodular skin lesions on his trunk and extremities. Biopsy revealed a CD30-positive lymphoma with pathological features characteristic of cutaneous anaplastic large cell lymphoma in the superficial dermis and a subjacent deposit of MCL in the deep dermis and subcutaneous adipose tissue. Immunophenotyping demonstrated T versus B lymphoid origin, respectively, for the 2 neoplasms, and fluorescence in situ hybridization demonstrated an 11;14 chromosomal translocation exclusively in the MCL. These results argue that the lymphomas represented clonally distinct neoplasms. Our case illustrates the extreme diversity associated with the cutaneous manifestations of lymphoid neoplasia and in particular of composite lymphomas, which present diagnostic challenges for clinicians and pathologists alike.


Assuntos
Linfoma de Célula do Manto/patologia , Linfoma Anaplásico Cutâneo Primário de Células Grandes/patologia , Neoplasias Complexas Mistas/patologia , Neoplasias Cutâneas/patologia , Idoso , Biomarcadores Tumorais/análise , Humanos , Imuno-Histoquímica , Masculino
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