Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 394
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Cell ; 176(3): 448-458.e12, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30639101

RESUMO

Cannabis elicits its mood-enhancing and analgesic effects through the cannabinoid receptor 1 (CB1), a G protein-coupled receptor (GPCR) that signals primarily through the adenylyl cyclase-inhibiting heterotrimeric G protein Gi. Activation of CB1-Gi signaling pathways holds potential for treating a number of neurological disorders and is thus crucial to understand the mechanism of Gi activation by CB1. Here, we present the structure of the CB1-Gi signaling complex bound to the highly potent agonist MDMB-Fubinaca (FUB), a recently emerged illicit synthetic cannabinoid infused in street drugs that have been associated with numerous overdoses and fatalities. The structure illustrates how FUB stabilizes the receptor in an active state to facilitate nucleotide exchange in Gi. The results compose the structural framework to explain CB1 activation by different classes of ligands and provide insights into the G protein coupling and selectivity mechanisms adopted by the receptor.


Assuntos
Receptor CB1 de Canabinoide/metabolismo , Receptor CB1 de Canabinoide/ultraestrutura , Animais , Agonistas de Receptores de Canabinoides/farmacologia , Canabinoides/farmacologia , Microscopia Crioeletrônica/métodos , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Humanos , Indazóis/farmacologia , Ligantes , Ligação Proteica , Receptor CB1 de Canabinoide/química , Receptores de Canabinoides/química , Receptores de Canabinoides/metabolismo , Receptores de Canabinoides/ultraestrutura , Receptores Acoplados a Proteínas G/metabolismo , Células Sf9 , Transdução de Sinais/efeitos dos fármacos
2.
Immunity ; 57(8): 1908-1922.e6, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39079535

RESUMO

In squamous cell carcinoma (SCC), macrophages responding to interleukin (IL)-33 create a TGF-ß-rich stromal niche that maintains cancer stem cells (CSCs), which evade chemotherapy-induced apoptosis in part via activation of the NRF2 antioxidant program. Here, we examined how IL-33 derived from CSCs facilitates the development of an immunosuppressive microenvironment. CSCs with high NRF2 activity redistributed nuclear IL-33 to the cytoplasm and released IL-33 as cargo of large oncosomes (LOs). Mechanistically, NRF2 increased the expression of the lipid scramblase ATG9B, which exposed an "eat me" signal on the LO surface, leading to annexin A1 (ANXA1) loading. These LOs promoted the differentiation of AXNA1 receptor+ myeloid precursors into immunosuppressive macrophages. Blocking ATG9B's scramblase activity or depleting ANXA1 decreased niche macrophages and hindered tumor progression. Thus, IL-33 is released from live CSCs via LOs to promote the differentiation of alternatively activated macrophage, with potential relevance to other settings of inflammation and tissue repair.


Assuntos
Diferenciação Celular , Interleucina-33 , Macrófagos , Células-Tronco Neoplásicas , Interleucina-33/metabolismo , Animais , Humanos , Camundongos , Macrófagos/imunologia , Macrófagos/metabolismo , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/metabolismo , Microambiente Tumoral/imunologia , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/metabolismo , Camundongos Endogâmicos C57BL , Proteínas Relacionadas à Autofagia/metabolismo , Linhagem Celular Tumoral
3.
Immunology ; 172(3): 392-407, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38504502

RESUMO

Treatment of tuberculosis (TB) is faced with several challenges including the long treatment duration, drug toxicity and tissue pathology. Host-directed therapy provides promising avenues to find compounds for adjunctively assisting antimycobacterials in the TB treatment regimen, by promoting pathogen eradication or limiting tissue destruction. Eicosanoids are a class of lipid molecules that are potent mediators of inflammation and have been implicated in aspects of the host response against TB. Here, we have explored the blood transcriptome of pulmonary TB patients to understand the activity of leukotriene B4, a pro-inflammatory eicosanoid. Our study shows a significant upregulation in the leukotriene B4 signalling pathway in active TB patients, which is reversed with TB treatment. We have further utilized our in-house network analysis algorithm, ResponseNet, to identify potential downstream signal effectors of leukotriene B4 in TB patients including STAT1/2 and NADPH oxidase at a systemic as well as local level, followed by experimental validation of the same. Finally, we show the potential of inhibiting leukotriene B4 signalling as a mode of adjunctive host-directed therapy against TB. This study provides a new mode of TB treatment along with mechanistic insights which can be further explored in pre-clinical trials.


Assuntos
Leucotrieno B4 , Mycobacterium tuberculosis , Transdução de Sinais , Tuberculose Pulmonar , Humanos , Leucotrieno B4/metabolismo , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/metabolismo , Mycobacterium tuberculosis/imunologia , Antituberculosos/uso terapêutico , Antituberculosos/farmacologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , NADPH Oxidases/metabolismo , Interações Hospedeiro-Patógeno
4.
Genes Dev ; 30(14): 1658-70, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27474443

RESUMO

RNA degradation is tightly regulated to selectively target aberrant RNAs, including viral RNA, but this regulation is incompletely understood. Through RNAi screening in Drosophila cells, we identified the 3'-to-5' RNA exosome and two components of the exosome cofactor TRAMP (Trf4/5-Air1/2-Mtr4 polyadenylation) complex, dMtr4 and dZcchc7, as antiviral against a panel of RNA viruses. We extended our studies to human orthologs and found that the exosome as well as TRAMP components hMTR4 and hZCCHC7 are antiviral. While hMTR4 and hZCCHC7 are normally nuclear, infection by cytoplasmic RNA viruses induces their export, forming a cytoplasmic complex that specifically recognizes and induces degradation of viral mRNAs. Furthermore, the 3' untranslated region (UTR) of bunyaviral mRNA is sufficient to confer virus-induced exosomal degradation. Altogether, our results reveal that signals from viral infection repurpose TRAMP components to a cytoplasmic surveillance role where they selectively engage viral RNAs for degradation to restrict a broad range of viruses.


Assuntos
Exossomos/metabolismo , Estabilidade de RNA/fisiologia , RNA Viral/metabolismo , Animais , Linhagem Celular , Citoplasma/metabolismo , Drosophila/virologia , Humanos , Complexos Multiproteicos/genética , Poliadenilação , Ligação Proteica , Transporte Proteico , Interferência de RNA , Infecções por Vírus de RNA/metabolismo , Infecções por Vírus de RNA/virologia , Vírus de RNA/fisiologia , Fatores de Transcrição/metabolismo
5.
Brain Behav Immun ; 112: 220-234, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37315702

RESUMO

Originally identified in fibroblasts, Protease Inhibitor (PI)16 was recently shown to be crucial for the development of neuropathic pain via effects on blood-nerve barrier permeability and leukocyte infiltration, though its impact on inflammatory pain has not been established. Using the complete Freund's Adjuvant inflammatory pain model, we show that Pi16-/- mice are protected against sustained inflammatory pain. Accordingly, intrathecal delivery of a PI16 neutralizing antibody in wild-type mice prevented sustained CFA pain. In contrast to neuropathic pain models, we did not observe any changes in blood-nerve barrier permeability due to PI16 deletion. Instead, Pi16-/- mice display reduced macrophage density in the CFA-injected hindpaw. Furthermore, there was a significant bias toward CD206hi (anti-inflammatory) macrophages in the hindpaw and associated dorsal root ganglia. Following CFA, intrathecal depletion of CD206+ macrophages using mannosylated clodronate liposomes promoted sustained pain in Pi16-/- mice. Similarly, an IL-10 neutralizing antibody also promoted sustained CFA pain in the Pi16-/ when administered intrathecally. Collectively, our results point to fibroblast-derived PI16 mediating substantial differences in macrophage phenotype in the pain neuroaxis under conditions of inflammation. The co-expression of PI16 alongside fibroblast markers in human DRG raise the likelihood that a similar mechanism operates in human inflammatory pain states. Collectively, our findings may have implications for targeting fibroblast-immune cell crosstalk for the treatment of chronic pain.


Assuntos
Dor Crônica , Neuralgia , Camundongos , Humanos , Animais , Inflamação , Macrófagos , Fibroblastos , Anticorpos Neutralizantes/farmacologia , Gânglios Espinais , Hiperalgesia , Proteínas de Transporte , Glicoproteínas
6.
Postgrad Med J ; 99(1171): 428-432, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37294722

RESUMO

PURPOSE: To elicit internal medicine residents' perspectives on wellness through poetry writing, examining (1) response rates, (2) the tone/sentiment of their submissions and (3) the primary thematic content. STUDY DESIGN: In academic year 2019-2020, a random sample of 88 residents from four internal medicine residency programmes was invited to participate in a year-long study of wellness. In December 2019, an open-ended prompt asked residents to write a poem reflecting on their well-being. Responses were inductively coded using content analysis techniques. RESULTS: The response rate for the poetry prompt was 94%. The tone of the entries was most often neutral or contradictory (42%), followed by negative (33%) and positive (25%). There were three main themes: (1) Mindsets: most residents simply wanted to make it through their programme; (2) wellness influencers: the main wellness supporters were external to the programme such as vacationing and exercise; within hospitals, friendships with colleagues and boosted wellness and (3) scheduling/repetition: difficult schedules drained energy as did the monotony of administrative tasks. CONCLUSIONS: Poetry appears to be an innovative and effective vehicle to elicit residents' perspectives without compromising response rate. Poetry survey techniques allow medical trainees to provide powerful messaging to leadership. Most of what is known about trainee wellness is derived from quantitative surveys. This study showed medicine trainees' willingness to engage in poetry and add richness and personal detail to highlight key drivers of wellness. Such information provides context and brings attention in a compelling manner to an important topic.


Assuntos
Esgotamento Profissional , Internato e Residência , Humanos , Inquéritos e Questionários , Redação , Esgotamento Profissional/prevenção & controle , Medicina Interna/educação
7.
Infect Immun ; 90(4): e0059721, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35311543

RESUMO

Streptococcus pneumoniae is a Gram-positive, encapsulated bacterium that is a significant cause of disease burden in pediatric and elderly populations. The rise in unencapsulated disease-causing strains and antimicrobial resistance in S. pneumoniae has increased the need for developing new antimicrobial strategies. Recent work by our laboratory has identified N,N-dimethyldithiocarbamate (DMDC) as a copper-dependent antimicrobial against bacterial, fungal, and parasitic pathogens. As a bactericidal antibiotic against S. pneumoniae, DMDC's ability to work as a copper-dependent antibiotic and its ability to work in vivo warranted further investigation. Here, our group studied the mechanisms of action of DMDC under various medium and excess-metal conditions and investigated DMDC's interactions with the innate immune system in vitro and in vivo. Of note, we found that DMDC plus copper significantly increased the internal copper concentration, hydrogen peroxide stress, nitric oxide stress, and the in vitro macrophage killing efficiency and decreased capsule. Furthermore, we found that in vivo DMDC treatment increased the quantity of innate immune cells in the lung during infection. Taken together, this study provides mechanistic insights regarding DMDC's activity as an antibiotic at the host-pathogen interface.


Assuntos
Anti-Infecciosos , Infecções Pneumocócicas , Idoso , Antibacterianos , Anti-Infecciosos/farmacologia , Criança , Cobre , Dimetilditiocarbamato , Humanos , Macrófagos , Streptococcus pneumoniae
8.
Br J Haematol ; 199(1): 95-99, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35694818

RESUMO

Belantamab mafodotin (BLMF) is a B-cell maturation antigen-directed antibody-drug conjugate, recently approved for advanced multiple myeloma (MM). The impact of BLMF-induced ocular toxicity on patient outcomes is unknown. We studied a cohort of 38 consecutively seen patients treated with BLMF outside of trials. Of those, 75% experienced ocular toxicity, with 69% developing keratopathy. Among patients requiring ocular toxicity-related permanent BLMF discontinuation (14%) or dose reduction (11%), 70% had progression of MM within a median of 3 months (95% confidence interval: 0.2-not reached) following BLMF interruption or dose reduction. Ocular toxicity is a major deterrent to the continuous use of BLMF in routine clinical practice. Measures to successfully prevent and mitigate ocular toxicity should be developed to achieve the full potential of this agent.


Assuntos
Imunoconjugados , Mieloma Múltiplo , Anticorpos Monoclonais Humanizados , Antígeno de Maturação de Linfócitos B , Humanos , Imunoconjugados/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Neuropatia Óptica Tóxica
9.
N Engl J Med ; 380(10): 905-914, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30855740

RESUMO

BACKGROUND: Concern persists that extended shifts in medical residency programs may adversely affect patient safety. METHODS: We conducted a cluster-randomized noninferiority trial in 63 internal-medicine residency programs during the 2015-2016 academic year. Programs underwent randomization to a group with standard duty hours, as adopted by the Accreditation Council for Graduate Medical Education (ACGME) in July 2011, or to a group with more flexible duty-hour rules that did not specify limits on shift length or mandatory time off between shifts. The primary outcome for each program was the change in unadjusted 30-day mortality from the pretrial year to the trial year, as ascertained from Medicare claims. We hypothesized that the change in 30-day mortality in the flexible programs would not be worse than the change in the standard programs (difference-in-difference analysis) by more than 1 percentage point (noninferiority margin). Secondary outcomes were changes in five other patient safety measures and risk-adjusted outcomes for all measures. RESULTS: The change in 30-day mortality (primary outcome) among the patients in the flexible programs (12.5% in the trial year vs. 12.6% in the pretrial year) was noninferior to that in the standard programs (12.2% in the trial year vs. 12.7% in the pretrial year). The test for noninferiority was significant (P = 0.03), with an estimate of the upper limit of the one-sided 95% confidence interval (0.93%) for a between-group difference in the change in mortality that was less than the prespecified noninferiority margin of 1 percentage point. Differences in changes between the flexible programs and the standard programs in the unadjusted rate of readmission at 7 days, patient safety indicators, and Medicare payments were also below 1 percentage point; the noninferiority criterion was not met for 30-day readmissions or prolonged length of hospital stay. Risk-adjusted measures generally showed similar findings. CONCLUSIONS: Allowing program directors flexibility in adjusting duty-hour schedules for trainees did not adversely affect 30-day mortality or several other measured outcomes of patient safety. (Funded by the National Heart, Lung, and Blood Institute and Accreditation Council for Graduate Medical Education; iCOMPARE ClinicalTrials.gov number, NCT02274818.).


Assuntos
Mortalidade Hospitalar , Medicina Interna/educação , Internato e Residência/organização & administração , Segurança do Paciente , Admissão e Escalonamento de Pessoal , Humanos , Internato e Residência/normas , Tempo de Internação , Readmissão do Paciente/estatística & dados numéricos , Admissão e Escalonamento de Pessoal/normas , Estados Unidos , Carga de Trabalho/normas
10.
N Engl J Med ; 380(10): 915-923, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30855741

RESUMO

BACKGROUND: A purpose of duty-hour regulations is to reduce sleep deprivation in medical trainees, but their effects on sleep, sleepiness, and alertness are largely unknown. METHODS: We randomly assigned 63 internal-medicine residency programs in the United States to follow either standard 2011 duty-hour policies or flexible policies that maintained an 80-hour workweek without limits on shift length or mandatory time off between shifts. Sleep duration and morning sleepiness and alertness were compared between the two groups by means of a noninferiority design, with outcome measures including sleep duration measured with actigraphy, the Karolinska Sleepiness Scale (with scores ranging from 1 [extremely alert] to 9 [extremely sleepy, fighting sleep]), and a brief computerized Psychomotor Vigilance Test (PVT-B), with long response times (lapses) indicating reduced alertness. RESULTS: Data were obtained over a period of 14 days for 205 interns at six flexible programs and 193 interns at six standard programs. The average sleep time per 24 hours was 6.85 hours (95% confidence interval [CI], 6.61 to 7.10) among those in flexible programs and 7.03 hours (95% CI, 6.78 to 7.27) among those in standard programs. Sleep duration in flexible programs was noninferior to that in standard programs (between-group difference, -0.17 hours per 24 hours; one-sided lower limit of the 95% confidence interval, -0.45 hours; noninferiority margin, -0.5 hours; P = 0.02 for noninferiority), as was the score on the Karolinska Sleepiness Scale (between-group difference, 0.12 points; one-sided upper limit of the 95% confidence interval, 0.31 points; noninferiority margin, 1 point; P<0.001). Noninferiority was not established for alertness according to the PVT-B (between-group difference, -0.3 lapses; one-sided upper limit of the 95% confidence interval, 1.6 lapses; noninferiority margin, 1 lapse; P = 0.10). CONCLUSIONS: This noninferiority trial showed no more chronic sleep loss or sleepiness across trial days among interns in flexible programs than among those in standard programs. Noninferiority of the flexible group for alertness was not established. (Funded by the National Heart, Lung, and Blood Institute and American Council for Graduate Medical Education; ClinicalTrials.gov number, NCT02274818.).


Assuntos
Medicina Interna/educação , Internato e Residência/organização & administração , Admissão e Escalonamento de Pessoal , Privação do Sono , Sonolência , Vigília , Tolerância ao Trabalho Programado , Actigrafia , Humanos , Admissão e Escalonamento de Pessoal/normas , Sono , Estados Unidos
11.
J Natl Compr Canc Netw ; 20(3): 218-223, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35276675

RESUMO

The stability of the human genome depends upon a delicate balance between replication by high- and low-fidelity DNA polymerases. Aberrant replication by error-prone polymerases or loss of function of high-fidelity polymerases predisposes to genetic instability and, in turn, cancer. DNA polymerase epsilon (Pol ε) is a high-fidelity, processive polymerase that is responsible for the majority of leading strand synthesis, and mutations in Pol ε have been increasingly associated with various human malignancies. The clinical significance of Pol ε mutations, including how and whether they should influence management decisions, remains poorly understood. In this report, we describe a 24-year-old man with an aggressive stage IV high-grade, poorly differentiated colon carcinoma who experienced a dramatic response to single-agent checkpoint inhibitor immunotherapy after rapidly progressing on standard chemotherapy. His response was complete and durable and has been maintained for more than 48 months. Genetic testing revealed a P286R mutation in the endonuclease domain of POLE and an elevated tumor mutational burden of 126 mutations per megabase, both of which have been previously associated with response to immunotherapy. Interestingly, tumor staining for PD-L1 was negative. This case study highlights the importance of genetic profiling of both early and late-stage cancers, the clinical significance of POLE mutations, and how the interplay between genetic instability and immune-checkpoint blockade can impact clinical decision-making.


Assuntos
Neoplasias Colorretais , DNA Polimerase II , Adulto , Biomarcadores Tumorais , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , DNA Polimerase II/genética , Humanos , Imunoterapia , Masculino , Mutação , Adulto Jovem
12.
BMC Neurol ; 22(1): 273, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869429

RESUMO

BACKGROUND: Automated infrared pupillometry (AIP) and the Neurological Pupil index (NPi) provide an objective means of assessing and trending the pupillary light reflex (PLR) across a broad spectrum of neurological diseases. NPi quantifies the PLR and ranges from 0 to 5; in healthy individuals, the NPi of both eyes is expected to be ≥ 3.0 and symmetric. AIP values demonstrate emerging value as a prognostic tool with predictive properties that could allow practitioners to anticipate neurological deterioration and recovery. The presence of an NPi differential (a difference ≥ 0.7 between the left and right eye) is a potential sign of neurological abnormality. METHODS: We explored NPi differential by considering the modified Rankin Score at discharge (DC mRS) among patients admitted to neuroscience intensive care units (NSICU) of 4 U.S. and 1 Japanese hospitals and for two cohorts of brain injuries: stroke (including subarachnoid hemorrhage, intracerebral hemorrhage, acute ischemic stroke, and aneurysm, 1,200 total patients) and 185 traumatic brain injury (TBI) patients for a total of more than 54,000 pupillary measurements. RESULTS: Stroke patients with at least 1 occurrence of an NPi differential during their NSICU stay have higher DC mRS scores (3.9) compared to those without an NPi differential (2.7; P < .001). Patients with TBI and at least 1 occurrence of an NPi differential during their NSICU stay have higher discharge modified Rankin Scale scores (4.1) compared to those without an NPi differential (2.9; P < .001). When patients experience both abnormalities, abnormal (NPi < 3.0) and an NPi differential, the latter has an anticipatory relationship with respect to the former (P < .001 for z-score skewness analysis). Finally, our analysis confirmed ≥ 0.7 as the optimal cutoff value for the NPi differential (AUC = 0.71, P < .001). CONCLUSION: The NPi differential is an important factor that clinicians should consider when managing critically ill neurological injured patients admitted to the neurocritical care units. TRIAL REGISTRATION: NCT02804438 , Date of Registration: June 17, 2016.


Assuntos
Lesões Encefálicas Traumáticas , AVC Isquêmico , Acidente Vascular Cerebral , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico , Humanos , Alta do Paciente , Pupila , Reflexo Pupilar , Acidente Vascular Cerebral/complicações
13.
J Intensive Care Med ; 37(10): 1288-1295, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35072539

RESUMO

Rationale: Geographic co-localization of patients and provider teams (geography) may improve care efficiency and quality. Patients requiring intermediate care present a unique challenge to the geographic model. Objective: Identify the best organizational and staffing model for intermediate care at our academic medical center. Methods: A modified nominal group technique was employed to assess the benefits and limitations of an existing model of intermediate care, identify and review potential alternative models, and choose a new model. Results: In addition to the institution's current model, the benefits and limitations of six alternative organizational and staffing models were characterized. The anticipated impact of each model on nurse: provider communication, maintenance of nursing competencies, nurse satisfaction, efficient utilization of technical and human resources, triage of patients to the unit, care continuity, and the impact on trainee education are described. After considering these features, stakeholders ranked a closed provider staffing model on a unit dedicated to intermediate care highest of the six alternative models. Important outcomes to monitor following transition to a closed staffing model included patient outcomes, nursing job satisfaction and retention, provider and trainee experience, unexpected patient transfers to higher or lower levels of care, and administrative costs. Conclusions: After considering six alternative staffing models for intermediate care, stakeholders ranked a closed provider staffing model highest. Further qualitative and quantitative comparisons to determine optimal models of intermediate care are needed.


Assuntos
Recursos Humanos de Enfermagem Hospitalar , Admissão e Escalonamento de Pessoal , Centros Médicos Acadêmicos , Humanos , Pacientes Internados , Recursos Humanos
14.
Am J Respir Crit Care Med ; 203(11): 1410-1418, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33326355

RESUMO

Rationale CC16 (club cell secretory protein) is a pneumoprotein produced predominantly by pulmonary club cells. Circulating CC16 is associated with protection from the inception and progression of the two most common obstructive lung diseases (asthma and chronic obstructive pulmonary disease). Objectives Although exact mechanisms remain elusive, studies consistently suggest a causal role of CC16 in mediating antiinflammatory and antioxidant functions in the lung. We sought to determine any novel receptor systems that could participate in CC16's role in obstructive lung diseases. Methods Protein alignment of CC16 across species led to the discovery of a highly conserved sequence of amino acids, leucine-valine-aspartic acid (LVD), a known integrin-binding motif. Recombinant CC16 was generated with and without the putative integrin-binding site. A Mycoplasma pneumoniae mouse model and a fluorescent cellular adhesion assay were used to determine the impact of the LVD site regarding CC16 function during live infection and on cellular adhesion during inflammatory conditions. Measurements and Main Results CC16 bound to integrin α4ß1), also known as the adhesion molecule VLA-4 (very late antigen 4), dependent on the presence of the LVD integrin-binding motif. During infection, recombinant CC16 rescued lung function parameters both when administered to the lung and intravenously but only when the LVD integrin-binding site was intact; likewise, neutrophil recruitment during infection and leukocyte adhesion were both impacted by the loss of the LVD site. Conclusions We discovered a novel receptor for CC16, VLA-4, which has important mechanistic implications for the role of CC16 in circulation as well as in the lung compartment.


Assuntos
Integrina alfa4beta1/metabolismo , Mycoplasma pneumoniae , Pneumonia por Mycoplasma/prevenção & controle , Uteroglobina/metabolismo , Animais , Adesão Celular , Modelos Animais de Doenças , Camundongos , Infiltração de Neutrófilos/fisiologia , Pneumonia por Mycoplasma/metabolismo , Ligação Proteica
15.
BMC Med Educ ; 22(1): 754, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36320029

RESUMO

BACKGROUND: Medical school academic achievements do not necessarily predict house staff job performance. This study explores a selection mechanism that improves house staff-program fit that enhances the Accreditation Council for Graduate Medical Education Milestones performance ratings. OBJECTIVE: Traditionally, house staff were selected primarily on medical school academic performance. To improve residency performance outcomes, the Program designed a theory-driven selection tool to assess house staff candidates on their personal values and goals fit with Program values and goals. It was hypothesized cohort performance ratings will improve because of the intervention. METHODS: Prospective quasi-experimental cohort design with data from two house staff cohorts at a university-based categorical Internal Medicine Residency Program. The intervention cohort, comprising 45 house staff from 2016 to 2017, was selected using a Behaviorally Anchored Rating Scales (BARS) tool for program fit. The control cohort, comprising 44 house staff from the prior year, was selected using medical school academic achievement scores. House staff performance was evaluated using ACGME Milestones indicators. The mean scores for each category were compared between the intervention and control cohorts using Student's t-tests with Bonferroni correction and Cohen's d for effect size. RESULTS: The cohorts were no different in academic performance scores at time of Program entry. The intervention cohort outperformed the control cohort on all 6 dimensions of Milestones by end-PGY1 and 3 of 6 dimensions by mid-PGY3. CONCLUSION: Selecting house staff based on compatibility with Residency Program values and objectives may yield higher job performance because trainees benefit more from a better fit with the training program.


Assuntos
Internato e Residência , Humanos , Estudos Prospectivos , Educação de Pós-Graduação em Medicina , Acreditação , Faculdades de Medicina , Competência Clínica , Avaliação de Programas e Projetos de Saúde
16.
Br J Cancer ; 124(3): 604-615, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33139797

RESUMO

BACKGROUND: To circumvent Warburg effect, several clinical trials for different cancers are utilising a combinatorial approach using metabolic reprogramming and chemotherapeutic agents including metformin. The majority of these metabolic interventions work via indirectly activating AMP-activated protein kinase (AMPK) to alter cellular metabolism in favour of oxidative phosphorylation over aerobic glycolysis. The effect of these drugs is dependent on glycaemic and insulin conditions.  Therefore, development of small molecules, which can activate AMPK, irrespective of the energy state, may be a better approach for triple-negative breast cancer (TNBC) treatment. METHODS: Therapeutic effect of SU212 on TNBC cells was examined using in vitro and in vivo models. RESULTS: We developed and characterised the efficacy of novel AMPK activator (SU212) that selectively induces oxidative phosphorylation and decreases glycolysis in TNBC cells, while not affecting these pathways in normal cells.   SU212 accomplished this metabolic reprogramming by activating AMPK independent of energy stress and irrespective of the glycaemic/insulin state. This leads to mitotic phase arrest and apoptosis in TNBC cells. In vivo, SU212 inhibits tumour growth, cancer progression and metastasis. CONCLUSIONS: SU212 directly activates AMPK in TNBC cells, but does not hamper glucose metabolism in normal cells. Our study provides compelling preclinical data for further development of SU212 for the treatment of TNBC.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Morte Celular , Fosforilação Oxidativa/efeitos dos fármacos , Podofilotoxina/análogos & derivados , Neoplasias de Mama Triplo Negativas/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Ativação Enzimática/efeitos dos fármacos , Feminino , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Ácido Láctico/metabolismo , Lipogênese/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas de Neoplasias/metabolismo , Distribuição Aleatória , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Efeito Warburg em Oncologia
17.
N Engl J Med ; 378(16): 1494-1508, 2018 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-29557719

RESUMO

BACKGROUND: Concern persists that inflexible duty-hour rules in medical residency programs may adversely affect the training of physicians. METHODS: We randomly assigned 63 internal medicine residency programs in the United States to be governed by standard duty-hour policies of the 2011 Accreditation Council for Graduate Medical Education (ACGME) or by more flexible policies that did not specify limits on shift length or mandatory time off between shifts. Measures of educational experience included observations of the activities of interns (first-year residents), surveys of trainees (both interns and residents) and faculty, and intern examination scores. RESULTS: There were no significant between-group differences in the mean percentages of time that interns spent in direct patient care and education nor in trainees' perceptions of an appropriate balance between clinical demands and education (primary outcome for trainee satisfaction with education; response rate, 91%) or in the assessments by program directors and faculty of whether trainees' workload exceeded their capacity (primary outcome for faculty satisfaction with education; response rate, 90%). Another survey of interns (response rate, 49%) revealed that those in flexible programs were more likely to report dissatisfaction with multiple aspects of training, including educational quality (odds ratio, 1.67; 95% confidence interval [CI], 1.02 to 2.73) and overall well-being (odds ratio, 2.47; 95% CI, 1.67 to 3.65). In contrast, directors of flexible programs were less likely to report dissatisfaction with multiple educational processes, including time for bedside teaching (response rate, 98%; odds ratio, 0.13; 95% CI, 0.03 to 0.49). Average scores (percent correct answers) on in-training examinations were 68.9% in flexible programs and 69.4% in standard programs; the difference did not meet the noninferiority margin of 2 percentage points (difference, -0.43; 95% CI, -2.38 to 1.52; P=0.06 for noninferiority). od Institute and the ACGME; iCOMPARE ClinicalTrials.gov number, NCT02274818 .). CONCLUSIONS: There was no significant difference in the proportion of time that medical interns spent on direct patient care and education between programs with standard duty-hour policies and programs with more flexible policies. Interns in flexible programs were less satisfied with their educational experience than were their peers in standard programs, but program directors were more satisfied. (Funded by the National Heart, Lung, and Blo


Assuntos
Atitude do Pessoal de Saúde , Competência Clínica , Administradores Hospitalares , Medicina Interna/educação , Internato e Residência/organização & administração , Carga de Trabalho/normas , Esgotamento Profissional/epidemiologia , Continuidade da Assistência ao Paciente , Docentes de Medicina , Humanos , Internato e Residência/normas , Satisfação no Emprego , Corpo Clínico Hospitalar , Admissão e Escalonamento de Pessoal/normas , Inquéritos e Questionários , Estudos de Tempo e Movimento , Estados Unidos , Tolerância ao Trabalho Programado
18.
Arch Pharm (Weinheim) ; 354(7): e2000393, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33749032

RESUMO

Cancer remains a leading cause of death worldwide, resulting in continuous efforts to discover and develop highly efficacious anticancer drugs. High-throughput screening of heterocyclic compound libraries is one of the promising approaches that provided several new lead molecules with a novel mechanism of action. On the basis of the promising anticancer potential of imidazoquinoxaline as well as the structurally similar imidazoquinoline-derived scaffold, we prepared a set of C6-substituted benzimidazo[1,2-a]quinoxaline derivatives via two novel synthetic routes using commercially available starting materials, with good to excellent yields and evaluated their anticancer activity against the NCI-60 cancer cell lines. The one-dose (10 µM) anticancer screening of the synthesized compounds in the NCI-60 cell line panel revealed that the substituents have a significant role in the activity. In particular, the indole (7f), imidazole (7g), and benzimidazole (7h) derivatives showed significant activity against the triple-negative breast cancer cell line, MDA-MB-468. The lead compounds also exhibited notable IC50 values against another breast cancer cell line, MCF-7. Furthermore, it was observed that these compounds were relatively nontoxic to normal cell lines: HEK293 (human embryonic kidney cell line) and MCF12A (nontumorigenic human breast epithelial cell line). The IC50 values against healthy cells were at least 5- to 11-fold higher, offering a new class of heterocycles that can be further developed as promising therapeutics for cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Imidazóis/farmacologia , Neoplasias/tratamento farmacológico , Quinoxalinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Imidazóis/síntese química , Imidazóis/química , Concentração Inibidora 50 , Neoplasias/patologia , Quinoxalinas/síntese química , Quinoxalinas/química , Relação Estrutura-Atividade
19.
Circulation ; 139(21): 2466-2482, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-30894016

RESUMO

BACKGROUND: Atherosclerosis progression is modulated by interactions with the adaptive immune system. Humoral immunity can help protect against atherosclerosis formation; however, the existence, origin, and function of putative atherogenic antibodies are controversial. How such atherosclerosis-promoting antibodies could affect the specific composition and stability of plaques, as well as the vasculature generally, remains unknown. METHODS: We addressed the overall contribution of antibodies to atherosclerosis plaque formation, composition, and stability in vivo (1) with mice that displayed a general loss of antibodies, (2) with mice that had selectively ablated germinal center-derived IgG production, or (3) through interruption of T-B-cell interactions and further studied the effects of antibody deficiency on the aorta by transcriptomics. RESULTS: Here, we demonstrate that atherosclerosis-prone mice with attenuated plasma cell function manifest reduced plaque burden, indicating that antibodies promote atherosclerotic lesion size. However, the composition of the plaque was altered in antibody-deficient mice, with an increase in lipid content and decreases in smooth muscle cells and macrophages, resulting in an experimentally validated vulnerable plaque phenotype. Furthermore, IgG antibodies enhanced smooth muscle cell proliferation in vitro in an Fc receptor-dependent manner, and antibody-deficient mice had decreased neointimal hyperplasia formation in vivo. These IgG antibodies were shown to be derived from germinal centers, and mice genetically deficient for germinal center formation had strongly reduced atherosclerosis plaque formation. mRNA sequencing of aortas revealed that antibodies are required for the sufficient expression of multiple signal-induced and growth-promoting transcription factors and that aortas undergo large-scale metabolic reprograming in their absence. Using an elastase model, we demonstrated that absence of IgG results in an increased severity of aneurysm formation. CONCLUSIONS: We propose that germinal center-derived IgG antibodies promote the size and stability of atherosclerosis plaques, through promoting arterial smooth muscle cell proliferation and maintaining the molecular identity of the aorta. These results could have implications for therapies that target B cells or B-T-cell interactions because the loss of humoral immunity leads to a smaller but less stable plaque phenotype.


Assuntos
Aorta/imunologia , Doenças da Aorta/imunologia , Aterosclerose/imunologia , Centro Germinativo/imunologia , Imunoglobulina G/imunologia , Placa Aterosclerótica , Animais , Antígenos CD19/genética , Antígenos CD19/metabolismo , Aorta/metabolismo , Aorta/patologia , Doenças da Aorta/genética , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Regulação da Expressão Gênica , Centro Germinativo/metabolismo , Imunoglobulina G/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Fator 1 de Ligação ao Domínio I Regulador Positivo/deficiência , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Ruptura Espontânea , Linfócitos T/imunologia , Linfócitos T/metabolismo
20.
Ophthalmology ; 127(11): 1454-1459, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32654758

RESUMO

PURPOSE: To determine the effect of implementing standardized opioid prescribing guidelines on prescription patterns for acute pain after ophthalmic surgery in opioid-naïve patients. DESIGN: Quality improvement study. PARTICIPANTS: Ophthalmic surgeons in an academic department of ophthalmology. METHODS: Postoperative opioid prescribing patterns were compared before and after the implementation of standardized opioid prescribing guidelines for ophthalmic surgery at an academic institution. Only prescriptions provided to opioid-naïve patients 18 years of age or older were included. Surgeons reached a consensus for standardized prescribing guidelines appropriate for the type of surgery within their subspecialty. Guidelines were disseminated in conjunction with postsurgical pain management education to all ophthalmologists in the department, including trainees. The frequency of opioid prescriptions, the quantity of opioid prescribed (converted to oral morphine equivalent [OME]), and opioid prescription refill rates were compared before and after intervention. MAIN OUTCOME MEASURES: Prescriptions with more than 80 OME, frequency of opioid prescriptions, mean OME, and refill rates. RESULTS: Of 5349 ophthalmic surgeries performed during the 2 assessment periods, 196 (3.7%) were associated with opioid prescriptions for acute postoperative pain. The frequency of opioid prescriptions decreased to 3.0% (81/2736) after intervention compared with 4.4% (115/2613) before intervention (P = 0.005). When opioids were prescribed, the mean OME decreased from 93 (range, 27-500) before intervention to 42 (range, 14-100) after intervention (P = 0.003). The number of prescriptions for more than 80 OME decreased from 56 (2.1%) before intervention to 4 (0.1%) after intervention (P < 0.001). Based on the standardized guidelines, 103 of the 115 (89.6%) preintervention opioid prescriptions would not have adhered to the guidelines, whereas 39 of the 81 (48.1%) postintervention prescriptions did not adhere to the guidelines (P < 0.001). The proportion of refill prescriptions did not differ before and after intervention (P = 0.44). CONCLUSIONS: The process of discussing postsurgical pain management and developing standardized opioid prescribing guidelines reduces overprescribing of opioids after ophthalmic surgery without increasing refill rates. Continued education is required to improve adherence to the prescribing guidelines further.


Assuntos
Analgésicos Opioides/uso terapêutico , Prescrições de Medicamentos/normas , Procedimentos Cirúrgicos Oftalmológicos/efeitos adversos , Dor Pós-Operatória/tratamento farmacológico , Padrões de Prática Médica/normas , Melhoria de Qualidade , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA