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1.
Subcell Biochem ; 88: 407-442, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29900506

RESUMO

Flaviviruses are positive, single-stranded, enveloped cytoplasmic sense RNA viruses that cause a variety of important diseases worldwide. Among them, Zika virus, West Nile virus, Japanese encephalitis virus, and Dengue virus have the potential to cause severe disease. Extensive studies have been performed to elucidate the structure and replication strategies of flaviviruses, and current studies are aiming to unravel the complex molecular interactions between the virus and host during the very early stages of infection. The outcomes of viral infection and rapid establishment of the antiviral state, depends on viral detection by pathogen recognition receptors and rapid initiation of signalling cascades to induce an effective innate immune response. Extracellular and intracellular pathogen recognition receptors play a crucial role in detecting flavivirus infection and inducing a robust antiviral response. One of the main hallmarks of flaviviral nonstructural proteins is their multiple strategies to antagonise the interferon system. In this chapter, we summarize the molecular characteristics of flaviviral proteins and discuss how viral proteins target different components of the interferon signalling pathway by blocking phosphorylation, enhancing degradation, and downregulating the expression of major components of the Janus kinase/signal transducer and activator of transcription pathway. We also discuss how the interactions of viral proteins with host proteins facilitate viral pathogenesis. Due to the lack of antivirals or prophylactic treatments for many flaviviral infections, it is necessary to fully elucidate how these viruses disrupt cellular processes to influence pathogenesis and disease outcomes.


Assuntos
Infecções por Flavivirus/imunologia , Flavivirus/imunologia , Imunidade Inata , Interferons/imunologia , Transdução de Sinais/imunologia , Proteínas não Estruturais Virais/imunologia , Animais , Flavivirus/patogenicidade , Infecções por Flavivirus/patologia , Humanos , Janus Quinases/imunologia
2.
Clin Exp Immunol ; 188(1): 109-126, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27886660

RESUMO

Listeriolysin O (LLO) has been proposed as a potential carrier or adjuvant molecule in the vaccination field. However, the cytotoxic and pro-apoptotic effects of LLO are the major limitations for this purpose. Here, we have performed a preclinical safety evaluation and characterized a new potential adjuvant application for a non-cytolytic LLO mutant (dtLLO) to enhance and modulate the immune response against the envelope (E) protein from dengue virus. In addition, we have studied the adjuvant effects of dtLLO on human immune cells and the role of membrane cholesterol for the binding and proinflammatory property of the toxoid. Our in-vivo results in the murine model confirmed that dtLLO is a safer molecule than wild-type LLO (wtLLO), with a significantly increased survival rate for mice challenged with dtLLO compared with mice challenged with wtLLO (P < 0·001). Histopathological analysis showed non-toxic effects in key target organs such as brain, heart, liver, spleen, kidney and lung after challenge with dtLLO. In vitro, dtLLO retained the capacity of binding to plasma membrane cholesterol on the surface of murine and human immune cells. Immunization of 6-8-week-old female BALB/c mice with a combination of dtLLO mixed with E protein elicited a robust specific humoral response with isotype diversification of immunoglobulin (Ig)G antibodies (IgG1 and IgG2a). Finally, we demonstrated that cholesterol and lipid raft integrity are required to induce a proinflammatory response by human cells. Taken together, these findings support a potential use of the dtLLO mutant as a safe and effective adjuvant molecule in vaccination.


Assuntos
Adjuvantes Imunológicos , Antígenos Virais/imunologia , Toxinas Bacterianas/imunologia , Vírus da Dengue/imunologia , Proteínas de Choque Térmico/imunologia , Proteínas Hemolisinas/imunologia , Imunidade Humoral , Proteínas Mutantes/imunologia , Animais , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos/imunologia , Toxinas Bacterianas/genética , Colesterol/metabolismo , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Dengue/imunologia , Dengue/patologia , Dengue/prevenção & controle , Modelos Animais de Doenças , Feminino , Proteínas de Choque Térmico/genética , Proteínas Hemolisinas/genética , Hemólise/imunologia , Imunização , Mediadores da Inflamação/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Lipídeos de Membrana/metabolismo , Camundongos , Proteínas Mutantes/genética , Ligação Proteica/imunologia
3.
J Nanosci Nanotechnol ; 17(1): 846-52, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-29634187

RESUMO

Biodegradables Chitosan-based Nanoparticles (CS NPs) have been extensively studied as delivery system for therapeutic molecules and as efficient carriers or adjuvants in experimental vaccination. Physicochemical association between CS NPs and antigens is a key step for the biological function as carrier devices. However, for the adjuvant CS NPs property, it is not well known if coupling with vaccine antigens is required or not to potentiate the immune response. To address this issue, in this work, we evaluated the potential adjuvant effect of CS NPs by simply mixing with two different antigens such as Bovine Serum Albumin (BSA) or E protein from Dengue Virus serotype 2 (E protein DENV2). Thus the CS NPs were prepared by ionic gelation with sodium tripolyphosphate, resulting particles among 68 and 188 nm of size. Immunization of 6­8 week old female BALB/c mice, were carried out by intraperitoneal route with a simple combination of CS NPs either with BSA (CS NPs-BSA) at 10 µg or with E protein DENV2 (CS NPs-Protein E) at 5 µg. Combinations with the above antigens with CS NPs elicited robust specific primary and secondary humoral responses comparable to alum, a well-known adjuvant. BSA-specific IgG titers were detectable by day 14 after priming with the CS NPs-BSA formulation, with titers that ranged from 102 to 103 EU ml-. After a second immunization, the anti-BSA titers ranged around 104 EU ml-. In contrast, in the group of mice immunized with the protein alone, BSA-specific serum IgG titers were undetectable at day 14 and 28. For the immunizations with the CS NPs-E protein formulation, we observed also a remarkable specific-antibody production in the primary response, with titers reaching 103 EU ml-. After the booster immunization the anti-E protein DENV2 antibodies titers reached peak values around 104 EU ml-. Interestingly, for both antigens, the combination with CS NPs polarized the immune response to a Th2-like profile, which is characterized mainly by the production of the IgG1 Isotype, confirming that CS NPs can enhance and modulate the humoral immune responses against different antigens independently of physicochemical conjugation. This could represent a simplification in the use of CS NPs as adjuvants in vaccination.


Assuntos
Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Compostos de Alúmen/química , Antígenos/química , Quitosana/química , Imunidade Humoral/efeitos dos fármacos , Nanopartículas/química , Animais , Antígenos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Soroalbumina Bovina/química , Soroalbumina Bovina/imunologia , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/imunologia
4.
J Dairy Sci ; 100(9): 6962-6971, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28734602

RESUMO

The aim of the present study was to evaluate the influence of rapeseed oilcake used for feeding sheep on the content of fatty acids (FA), tocopherols, retinoids, and cholesterol of milk and cheese, and on the sensory properties of cheese. Indoor animal feeding (in winter) is the highest cost of production for cheesemakers, and the inclusion of locally produced rapeseed oilcake in the concentrate feed formulation can reduce the cost of cheese production, as long as the quality of the cheese is not altered. The experiment was carried out in March (mid lactation) with 72 Latxa sheep from an experimental farm located in the Basque Country (northern Spain). Two homogeneous groups of animals (n = 36) were set to receive each a different diet based on commercial or rapeseed concentrate, respectively, and forage (Festuca hay). Animal production parameters were individually recorded for each feeding group, whereas bulk milk from each group was used for cheesemaking trials. The rapeseed concentrate had higher amounts of unsaturated FA (mainly C18:1 cis isomers, C18:2 cis-9,cis-12 and C18:3 cis-9,cis-12,cis-15) and tocopherols than the commercial concentrate. The inclusion of rapeseed oilcake in the diet of dairy sheep did not compromise animal production parameters or milk gross composition. Bulk milk and cheese from sheep fed rapeseed concentrate showed higher content of unsaturated FA and tocopherols than those from sheep fed commercial concentrate. No differences were observed in the content of retinoid in milk and cheese between feeding groups, whereas the cholesterol content was slightly lower in cheese made with milk from sheep fed rapeseed concentrate. Thus, milk and cheese from sheep fed rapeseed concentrate had a healthier lipid profile. In addition, the inclusion of rapeseed oilcake in the diet of sheep did not change the typical sensory attributes of Protected Denomination of Origin Idiazabal cheese. Therefore, rapeseed concentrate could be a good local resource for feeding sheep to improve the nutritional quality of dairy products and to provide higher returns to farms.


Assuntos
Queijo/análise , Colesterol/análise , Ácidos Graxos/análise , Leite/química , Óleo de Brassica napus/administração & dosagem , Retinoides/análise , Tocoferóis/análise , Vitaminas/análise , Ração Animal , Animais , Brassica rapa , Dieta , Feminino , Lactação , Ovinos , Espanha , Paladar
5.
South Med J ; 110(3): 172-180, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28257541

RESUMO

OBJECTIVES: Antibiotics for acute respiratory illness (ARI) constitute most pediatric medication use and contribute to the emergence of antimicrobial resistance. We investigated antibiotic prescription risk factors for ARI in pediatric clinics and clinical follow-up in individuals prescribed and not prescribed antibiotics. METHODS: In this observational study, we enrolled children ages 2 to 17 years old presenting with ARI with fever to two academic pediatric primary care outpatient clinics during influenza season 2013-2014. We collected information on demographics, initial symptoms, medical conditions, laboratory tests, discharge diagnoses, treatments, and 30 days of follow-up medical encounters. Factors associated with antibiotic prescription receipt were evaluated using logistic regression. RESULTS: Of 206 consented and enrolled children, 59 (29%) were prescribed antibiotics, 51 of 59 (86%) for indicated diagnoses: 34 for streptococcal pharyngitis, 15 for acute otitis media (AOM), and 2 for pneumonia. Discharge diagnoses were the only factors independently associated with an antibiotic prescription. Of children prescribed/not prescribed an antibiotic, 17%/17% received follow-up telephone calls and 27%/17% had follow-up visits related to ARI within 30 days. Two children with AOM were prescribed a second antibiotic during follow-up, and one developed Clostridium difficile colitis. Eighteen of 206 (9%) additional children were prescribed antibiotics within 30 days for ARI symptoms, 17 for streptococcal pharyngitis, AOM, pneumonia, or sinusitis; one was prescribed antibiotics for influenza-like illness. CONCLUSIONS: Among study children 2 to 17 years old with outpatient ARI, 29% were prescribed antibiotics at the initial visit and another 9% were prescribed antibiotics during the 30-day follow-up (most were for appropriate indications). Further decreasing antibiotic use in similar settings will likely require wider implementation of watchful waiting for AOM, a change in guidelines for pharyngitis management, and/or reductions in these diseases.


Assuntos
Antibacterianos/uso terapêutico , Prescrições de Medicamentos/estatística & dados numéricos , Otite Média/tratamento farmacológico , Faringite/tratamento farmacológico , Pneumonia/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Continuidade da Assistência ao Paciente , Feminino , Humanos , Masculino , Fatores de Risco , Tennessee
6.
J Pediatr ; 166(5): 1240-1245.e1, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25720366

RESUMO

OBJECTIVE: To assess how frequently pediatric practitioners perform latent tuberculosis infection (LTBI) screening according to guidelines. We hypothesized that screening occurs less frequently among children whose parents do not speak English as the primary language. STUDY DESIGN: We conducted a retrospective cohort study of patients attending well-child visits in an urban academic pediatric primary care clinic between April 1, 2012, and March 31, 2013. We assessed documentation of 3 LTBI screening components and tested the association between parent primary language and tuberculin skin test (TST) placement and documentation of results. RESULTS: During the study period, 387 of 9143 children (4%) had no documentation of screening question responses. Among the other 8756 children, 831 (10%) were identified as at high risk for LTBI. Of these, 514 (62%) did not have documented TST placement in the appropriate time frame. Thirty-nine of 213 children (18%) who had a TST placed did not have documented results. Multivariable regression showed that parent language was not associated with TST placement or documentation of results, but non-Hispanic Black children were more likely to not have a documented test result (aOR, 2.12; 95% CI, 1.07-4.19; P=.03) when adjusting for age, sex, parent primary language, insurance status, day of the week, and study year of TST placement. CONCLUSION: Parent primary language was not associated with LTBI testing. However, we found substantial gaps in TST placement and documentation of TST results among high-risk children, the latter of which was associated with race/ethnicity. Targeted quality improvement efforts should focus on developing processes to ensure complete screening in high-risk children.


Assuntos
Tuberculose Latente/diagnóstico , Programas de Rastreamento/métodos , Atenção Primária à Saúde/métodos , Adolescente , Criança , Pré-Escolar , Registros Eletrônicos de Saúde , Feminino , Humanos , Lactente , Masculino , Análise Multivariada , Estudos Retrospectivos , Tennessee , Teste Tuberculínico
7.
Matern Child Health J ; 19(6): 1384-92, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25467179

RESUMO

Developing improved systems of care for children with special health care needs (CSHCN) requires accurate identification and stratification of this population. This study was designed to assess the ability of a brief screener to identify and stratify CSHCN in a primary care clinic to focus future quality improvement initiatives and allocate resources. All families presenting for health maintenance visits or acute care appointments at an academic primary care clinic between September 5, 2012 and September 28, 2012 were asked to complete the CSHCN Screener(©). This panel of patients was compared to registries previously created by: (1) retrospective chart reviews using published lists of International Statistical Classification of Diseases and Related Health Problems (ICD9) codes for CSHCN and (2) direct physician referral to a clinic case manager providing care coordination services to CSHCN. Screeners identified 246 CSHCN (16.8 % of unique completed screeners). Scores ranged from 0 to 5; higher scores indicate higher levels of complexity. Patients with positive screens had a mean score of 2.4. Patients previously identified by retrospective ICD9 search who completed a screener had a mean score of 1.6 with nearly one-half having negative screens. Patients previously identified by physician referral who completed a screener had a mean score of 2.7 with nearly one-half having scores of 4 or 5. The CSHCN Screener(©) can be utilized in an academic primary care clinic to prospectively identify CSHCN and potentially offers a more clinically meaningful method of identification given its inherent ability to stratify this population based on complexity of medical needs.


Assuntos
Assistência Ambulatorial/métodos , Serviços de Saúde da Criança/organização & administração , Assistência Ambulatorial/organização & administração , Criança , Pré-Escolar , Crianças com Deficiência , Feminino , Humanos , Lactente , Masculino , Programas de Rastreamento/métodos , Atenção Primária à Saúde/métodos , Atenção Primária à Saúde/organização & administração , Inquéritos e Questionários
8.
Immunol Invest ; 43(1): 28-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24063571

RESUMO

Dengue virus (DENV) RNA replication requires 2 viral proteins, non-structural protein 3 (NS3) and NS5. NS5 consists of 2 functional domains: a methyltransferase (MTase) domain involved in RNA cap formation and located in the amino terminal region and a RNA-dependent RNA polymerase domain essential for virus replication and located in the carboxyl terminal region. To gain additional insight into the structural interactions between viral proteins and cellular factors involved in DENV RNA replication, we generated a panel of rat monoclonal antibodies (mAbs) against the NS5 MTase domain. Six rat mAbs were selected from 41 clones, of which clone 13G7 was further characterized. The specificity of this antibody for NS5 was demonstrated by western blot of DENV-infected cells, which revealed that this antibody recognizes all 4 DENV serotypes. Furthermore, Western blotting analysis suggested that this antibody recognizes a sequential epitope of the NS5 protein. Positive and specific staining with 13G7 was detected predominantly in nuclei of DENV-infected cells, similarly a pattern was observed in both in human and monkey cells. Furthermore, the NS5 staining co-localized with a Lamin A protein (Pierson index: 0.7). In summary, this monoclonal antibody could be used to identify and evaluate different cellular factors that may interact with NS5 during DENV replication.


Assuntos
Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , RNA Polimerases Dirigidas por DNA/imunologia , Vírus da Dengue/imunologia , Proteínas não Estruturais Virais/imunologia , Animais , Especificidade de Anticorpos/imunologia , Linhagem Celular , Chlorocebus aethiops , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/isolamento & purificação , RNA Polimerases Dirigidas por DNA/metabolismo , Vírus da Dengue/classificação , Vírus da Dengue/genética , Humanos , Lamina Tipo A/metabolismo , Ligação Proteica/imunologia , Transporte Proteico , Ratos , Sorotipagem , Células Vero , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/isolamento & purificação , Proteínas não Estruturais Virais/metabolismo
9.
J Autism Dev Disord ; 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38289527

RESUMO

PURPOSE: A high-quality primary care clinic should provide clear action points and important care coordination for a child receiving a new diagnosis of autism spectrum disorder (ASD). Unfortunately, a substantial proportion of caregivers report little-to-no post-diagnosis support from their home clinics and primary care providers often report lack of training and resources in providing these supports. METHODS: We implemented an intervention package to investigate the impact on the frequency and quality of follow-up care for children with ASD in a busy, high-volume resident continuity clinic. The package consisted of a care coordination scheduling pathway and a standardized clinical template-embedded in the electronic health record (EHR)-that guided providers through best-practice recommendations and patient resources. RESULTS: As a result of these interventions, 74% of patients had ASD-specific follow-up, a more than threefold increase from baseline with a majority of providers using the EHR-embedded template to guide their visit. Providers also indicated a high degree of usability for the system and that it aided them in following best-practice guidelines for ASD care. CONCLUSION: Through explicit scheduling pathways and a novel EHR template, we saw a significant increase in ASD-specific follow-up visits and implementation of best practices for ASD care, demonstrating a new process for training and engaging primary care providers in clear action steps for post-diagnostic care without having to rely on tertiary referrals.

10.
J Med Internet Res ; 15(7): e141, 2013 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-23864345

RESUMO

BACKGROUND: Self-report is the most common method of measuring medication adherence but is influenced by recall error and response bias, and it typically does not provide insight into the causes of poor adherence. Ecological momentary assessment (EMA) of health behaviors using mobile phones offers a promising alternative to assessing adherence and collecting related data that can be clinically useful for adherence problem solving. OBJECTIVE: To determine the feasibility of using EMA via mobile phones to assess adolescent asthma medication adherence and identify contextual characteristics of adherence decision making. METHODS: We utilized a descriptive and correlational study design to explore a mobile method of symptom and adherence assessment using an interactive voice response system. Adolescents aged 12-18 years with a diagnosis of asthma and prescribed inhalers were recruited from an academic medical center. A survey including barriers to mobile phone use, the Illness Management Survey, and the Pediatric Asthma Quality of Life Questionnaire were administered at baseline. Quantitative and qualitative assessment of asthma symptoms and adherence were conducted with daily calls to mobile phones for 1 month. The Asthma Control Test (ACT) was administered at 2 study time points: baseline and 1 month after baseline. RESULTS: The sample consisted of 53 adolescents who were primarily African American (34/53, 64%) and female (31/53, 58%) with incomes US$40K/year or lower (29/53, 55%). The majority of adolescents (37/53, 70%) reported that they carried their phones with them everywhere, but only 47% (25/53) were able to use their mobile phone at school. Adolescents responded to an average of 20.1 (SD 8.1) of the 30 daily calls received (67%). Response frequency declined during the last week of the month (b=-0.29, P<.001) and was related to EMA-reported levels of rescue inhaler adherence (r= 0.33, P=.035). Using EMA, adolescents reported an average of 0.63 (SD 1.2) asthma symptoms per day and used a rescue inhaler an average of 70% of the time (SD 35%) when they experienced symptoms. About half (26/49, 53%) of the instances of nonadherence took place in the presence of friends. The EMA-measured adherence to rescue inhaler use correlated appropriately with asthma control as measured by the ACT (r=-0.33, P=.034). CONCLUSIONS: Mobile phones provided a feasible method to assess asthma symptoms and adherence in adolescents. The EMA method was consistent with the ACT, a widely established measure of asthma control, and results provided valuable insights regarding the context of adherence decision making that could be used clinically for problem solving or as feedback to adolescents in a mobile or Web-based support system.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Asma/fisiopatologia , Telefone Celular , Cooperação do Paciente , Adolescente , Criança , Feminino , Humanos , Masculino
11.
Nano Lett ; 12(7): 3640-4, 2012 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-22594393

RESUMO

Using a modal matching theory, we demonstrate the generation of short-range, chiral electromagnetic fields via the excitation of arrays of staggered nanoslits that are chiral in two dimensions. The electromagnetic near fields, which exhibit a chiral density greater than that of circularly polarized light, can enhance the chiroptical interactions in the vicinity of the nanoslits. We discuss the features of nanostructure symmetry required to obtain the chiral fields and explicitly show how these structures can give rise to detection and characterization of materials with chiral symmetry.

12.
J Vet Cardiol ; 48: 7-18, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37276765

RESUMO

BACKGROUND: Echocardiographic indices of the inferior vena cava have been associated with elevated right atrial pressures in humans. HYPOTHESIS/OBJECTIVES: Describe caudal vena caval (CVC) sonographic dimensions in healthy cats compared to cats with cardiogenic cavitary effusion (CCE), cardiogenic pulmonary edema (CPE), or non-cardiac causes of cavitary effusion (NCE). ANIMALS: 30 healthy control cats and 52 client-owned cats with CCE, CPE, or NCE examined at two university hospitals. METHODS: Sagittal 2-dimensional (2D) and M-mode CVC dimensions were acquired from the subxiphoid view. Caudal vena cava collapsibility index (CVC-CI) was calculated. Variables were compared between study groups using Kruskal-Wallis and Dunn's Bonferroni testing. Receiver operating characteristic curves were used to assess sensitivity and specificity for diagnostic categories. RESULTS: Healthy cats had sagittal 2D and M-mode (median, interquartile range) CVC maximal dimensions of 2.4 mm (1.3-4.0) and 3.4 mm (1.5-4.9) and CVC-CI of 52% (45.2-61.8) and 55% (47.8-61.3), respectively. The CVC maximal dimensions in healthy controls were smaller than in cats with cavitary effusions or pulmonary edema (all P<0.05). CVC-CI was different between CCE and NCE (P<0.0001) with cutoffs of CVC-CI ≤38% (2D) or ≤29% (M-mode) being 90.5% and 85.7% sensitive, and 94.4% and 100% specific for diagnosis of CCE, respectively. CONCLUSIONS AND CLINICAL IMPORTANCE: Caudal vena cava measurements are larger in cats with cavitary effusions and cats with CPE than healthy cats. In cats with cavitary effusion, decreased CVC-CI, ≤38% (2D) or ≤29% (M-mode), was helpful in distinguishing between cardiogenic and noncardiogenic etiology.


Assuntos
Doenças do Gato , Insuficiência Cardíaca , Edema Pulmonar , Humanos , Gatos , Animais , Edema Pulmonar/veterinária , Veia Cava Inferior/diagnóstico por imagem , Ecocardiografia/veterinária , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/veterinária , Insuficiência Cardíaca/complicações , Ultrassonografia/veterinária , Doenças do Gato/diagnóstico por imagem
13.
medRxiv ; 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36865144

RESUMO

Objective: To determine if ChatGPT can generate useful suggestions for improving clinical decision support (CDS) logic and to assess noninferiority compared to human-generated suggestions. Methods: We supplied summaries of CDS logic to ChatGPT, an artificial intelligence (AI) tool for question answering that uses a large language model, and asked it to generate suggestions. We asked human clinician reviewers to review the AI-generated suggestions as well as human-generated suggestions for improving the same CDS alerts, and rate the suggestions for their usefulness, acceptance, relevance, understanding, workflow, bias, inversion, and redundancy. Results: Five clinicians analyzed 36 AI-generated suggestions and 29 human-generated suggestions for 7 alerts. Of the 20 suggestions that scored highest in the survey, 9 were generated by ChatGPT. The suggestions generated by AI were found to offer unique perspectives and were evaluated as highly understandable and relevant, with moderate usefulness, low acceptance, bias, inversion, redundancy. Conclusion: AI-generated suggestions could be an important complementary part of optimizing CDS alerts, can identify potential improvements to alert logic and support their implementation, and may even be able to assist experts in formulating their own suggestions for CDS improvement. ChatGPT shows great potential for using large language models and reinforcement learning from human feedback to improve CDS alert logic and potentially other medical areas involving complex, clinical logic, a key step in the development of an advanced learning health system.

14.
J Am Med Inform Assoc ; 30(7): 1237-1245, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37087108

RESUMO

OBJECTIVE: To determine if ChatGPT can generate useful suggestions for improving clinical decision support (CDS) logic and to assess noninferiority compared to human-generated suggestions. METHODS: We supplied summaries of CDS logic to ChatGPT, an artificial intelligence (AI) tool for question answering that uses a large language model, and asked it to generate suggestions. We asked human clinician reviewers to review the AI-generated suggestions as well as human-generated suggestions for improving the same CDS alerts, and rate the suggestions for their usefulness, acceptance, relevance, understanding, workflow, bias, inversion, and redundancy. RESULTS: Five clinicians analyzed 36 AI-generated suggestions and 29 human-generated suggestions for 7 alerts. Of the 20 suggestions that scored highest in the survey, 9 were generated by ChatGPT. The suggestions generated by AI were found to offer unique perspectives and were evaluated as highly understandable and relevant, with moderate usefulness, low acceptance, bias, inversion, redundancy. CONCLUSION: AI-generated suggestions could be an important complementary part of optimizing CDS alerts, can identify potential improvements to alert logic and support their implementation, and may even be able to assist experts in formulating their own suggestions for CDS improvement. ChatGPT shows great potential for using large language models and reinforcement learning from human feedback to improve CDS alert logic and potentially other medical areas involving complex, clinical logic, a key step in the development of an advanced learning health system.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Sistema de Aprendizagem em Saúde , Humanos , Inteligência Artificial , Idioma , Fluxo de Trabalho
15.
Pediatr Qual Saf ; 7(3): e553, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720875

RESUMO

Introduction: Acute otitis media (AOM) is the most common reason for antibiotic use in children. The American Academy of Pediatrics (AAP) published its latest AOM guidelines in 2013. A safety-net antibiotic prescription (SNAP) is recommended for some patients based on age, severity, and duration of symptoms. At baseline, 78% of patients diagnosed with AOM in our general pediatrics practice met AAP guidelines, and 20% of eligible patients received a SNAP according to guidelines. We aimed to increase adherence to AAP AOM guidelines in an academic general pediatrics clinic from 78% to 90% by January 2020. Methods: A quality improvement team determined key drivers and developed interventions. Patients included were 6 months to 12 years old with AOM. Encounters were reviewed for adherence to AAP AOM guidelines. During the project, interventions included an ear pain note template, which generated guideline-based recommendations, note template education in clinic orientation sessions, a didactic session on AOM management, and reminders on workstations. Data were analyzed using P-charts. Results: Percent of AOM encounters (n = 1266) adhering to AAP AOM guidelines increased from 78% to 92%. We also reviewed two process measures. First, the use of the ear pain note template increased from 0% to 44%. Second, the percent of AOM encounters where an eligible patient received a SNAP increased from 21% to 78% (encounters n = 421). Conclusion: We demonstrate increased adherence to AAP AOM guidelines, including improved use of SNAPs after introducing a note template with clinical decision support and provider educational sessions.

16.
J Vet Cardiol ; 40: 99-109, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33741312

RESUMO

INTRODUCTION: Dilated cardiomyopathy (DCM) in dogs has been associated with feeding of grain-free (GF), legume-rich diets. Some dogs with presumed diet-associated DCM have shown improved myocardial function and clinical outcomes following a change in diet and standard medical therapy. HYPOTHESIS: Prior GF (pGF) diet influences reverse cardiac remodeling and clinical outcomes in dogs with DCM and congestive heart failure (CHF). ANIMALS AND METHODS: A retrospective study was performed with 67 dogs with DCM and CHF for which diet history was known. Dogs were grouped by diet into pGF and grain-inclusive (GI) groups. Dogs in the pGF group were included if diet change was a component of therapy. Survival was analyzed using Kaplan-Meier curves and the Cox proportional-hazards model. RESULTS: The median survival time was 344 days for pGF dogs vs. 253 days for GI dogs (P = 0.074). Statistically significant differences in median survival were identified when the analysis was limited to dogs surviving longer than one week (P = 0.033). Prior GF dogs had a significantly worse outcome the longer a GF diet was fed prior to diagnosis (P = 0.004) or if they were diagnosed at a younger age (P = 0.017). Prior GF dogs showed significantly greater improvement in normalized left ventricular internal diastolic diameter (P = 0.038) and E-point septal separation (P = 0.031) measurements and significant decreases in their furosemide (P = 0.009) and pimobendan (P < 0.005) dosages over time compared to GI dogs. CONCLUSIONS: Prior GF dogs that survived at least one week after diagnosis of DCM, treatment of CHF, and diet change had better clinical outcomes and showed reverse ventricular remodeling compared to GI dogs.


Assuntos
Cardiomiopatia Dilatada , Doenças do Cão , Insuficiência Cardíaca , Animais , Cães , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/veterinária , Dieta/veterinária , Doenças do Cão/diagnóstico , Ecocardiografia/veterinária , Grão Comestível , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/veterinária , Estudos Retrospectivos
17.
J Am Med Inform Assoc ; 29(6): 1050-1059, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35244165

RESUMO

OBJECTIVE: We describe the Clickbusters initiative implemented at Vanderbilt University Medical Center (VUMC), which was designed to improve safety and quality and reduce burnout through the optimization of clinical decision support (CDS) alerts. MATERIALS AND METHODS: We developed a 10-step Clickbusting process and implemented a program that included a curriculum, CDS alert inventory, oversight process, and gamification. We carried out two 3-month rounds of the Clickbusters program at VUMC. We completed descriptive analyses of the changes made to alerts during the process, and of alert firing rates before and after the program. RESULTS: Prior to Clickbusters, VUMC had 419 CDS alerts in production, with 488 425 firings (42 982 interruptive) each week. After 2 rounds, the Clickbusters program resulted in detailed, comprehensive reviews of 84 CDS alerts and reduced the number of weekly alert firings by more than 70 000 (15.43%). In addition to the direct improvements in CDS, the initiative also increased user engagement and involvement in CDS. CONCLUSIONS: At VUMC, the Clickbusters program was successful in optimizing CDS alerts by reducing alert firings and resulting clicks. The program also involved more users in the process of evaluating and improving CDS and helped build a culture of continuous evaluation and improvement of clinical content in the electronic health record.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Sistemas de Registro de Ordens Médicas , Registros Eletrônicos de Saúde , Humanos
18.
Oncogene ; 40(11): 2065-2080, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33627784

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most intractable and devastating malignant tumors. Epigenetic modifications such as DNA methylation and histone modification regulate tumor initiation and progression. However, the contribution of histone variants in PDAC is unknown. Here, we demonstrated that the histone variant H2A.Z is highly expressed in PDAC cell lines and PDAC patients and that its overexpression correlates with poor prognosis. Moreover, all three H2A.Z isoforms (H2A.Z.1, H2A.Z.2.1, and H2A.Z.2.2) are highly expressed in PDAC cell lines and PDAC patients. Knockdown of these H2A.Z isoforms in PDAC cell lines induces a senescent phenotype, cell cycle arrest in phase G2/M, increased expression of cyclin-dependent kinase inhibitor CDKN2A/p16, SA-ß-galactosidase activity and interleukin 8 production. Transcriptome analysis of H2A.Z-depleted PDAC cells showed altered gene expression in fatty acid biosynthesis pathways and those that regulate cell cycle and DNA damage repair. Importantly, depletion of H2A.Z isoforms reduces the tumor size in a mouse xenograft model in vivo and sensitizes PDAC cells to gemcitabine. Overexpression of H2A.Z.1 and H2A.Z.2.1 more than H2A.Z.2.2 partially restores the oncogenic phenotype. Therefore, our data suggest that overexpression of H2A.Z isoforms enables cells to overcome the oncoprotective barrier associated with senescence, favoring PDAC tumor grow and chemoresistance. These results make H2A.Z a potential candidate as a diagnostic biomarker and therapeutic target for PDAC.


Assuntos
Adenocarcinoma/genética , Carcinoma Ductal Pancreático/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , beta-Galactosidase/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Envelhecimento/genética , Animais , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Transformação Celular Neoplásica/genética , Dano ao DNA/efeitos dos fármacos , Metilação de DNA/genética , Reparo do DNA/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Epigênese Genética/genética , Xenoenxertos , Histonas/genética , Humanos , Camundongos , Gencitabina
19.
Cancer Invest ; 28(5): 452-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19863344

RESUMO

It has been recently demonstrated that progranulin is overexpressed in ovarian cancer and that this protein is involved in the stimulation of cell proliferation, malignancy, and chemoresistance in ovarian cancer. The goal of the present study was to establish the differences in progranulin expression among normal, benign, and malignant ovarian tissues and to identify the signal transduction pathways activated by progranulin in an ovarian cancer cell line. Compared with benign tumors and normal ovarian tissue, progranulin mRNA and protein were overexpressed in malignant tumors. Survival analysis by the Kaplan-Meier method showed a correlation between high mRNA expression levels with poor survival outcome. Progranulin activated the MAPK-signaling pathway in NIH-OVCAR-3 cells. Progranulin expression may be potentially involved in the pathogenesis and malignant progression of ovarian cancer, and thus may represent a therapeutic target for this particular malignancy.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Ovarianas/metabolismo , Ovário/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Sistema de Sinalização das MAP Quinases , Pessoa de Meia-Idade , Neoplasias Ovarianas/mortalidade , Progranulinas
20.
J Dairy Sci ; 93(9): 3902-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20723663

RESUMO

Ewe raw milk composition, rennet coagulation parameters, and curd texture were monitored throughout the milk production season in 11 commercial flocks reared under a part-time grazing system. Milking season lasted from February to July. During that period, the diet of the animals shifted from indoor feeding, consisting of concentrate and forage, to an outdoor grazing diet. Lean dry matter, fat, protein, calcium, and magnesium contents increased throughout the milking season, as did rennet coagulation time, curd firmness, and curd resistance to compression. However, lean dry matter, protein content, and curd resistance to compression stabilized when sheep started to graze. Principal component analysis correlated curd resistance to compression and proteins, whereas curd firmness was highly correlated with fat content and minerals. Discriminant analysis distributed milk samples according to the feeding management. Curd firmness, fat, and magnesium turned out to be discriminant variables. Those variables reflected the evolution of the composition and coagulation parameters when fresh pasture prevailed over other feeds in the diet of the flocks. The present study shows that seasonal changes associated with feeding management influence milk technological quality and that milk of good processing quality can be obtained under part-time grazing.


Assuntos
Indústria de Laticínios/métodos , Leite/química , Ovinos , Ração Animal , Criação de Animais Domésticos/métodos , Animais , Caseínas/análise , Quimosina/metabolismo , Dieta/veterinária , Gorduras/análise , Feminino , Concentração de Íons de Hidrogênio , Proteínas do Leite/análise , Estações do Ano , Ovinos/fisiologia , Espanha
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