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1.
AIDS ; 38(3): 317-327, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37788081

RESUMO

BACKGROUND: Proprotein convertase subtisilin/kexin 9 (PCSK9) raises low-density lipoprotein cholesterol (LDL-C) levels and is associated with inflammation, which is elevated in HIV and hepatitis C virus (HCV) infection. We compared PCSK9 levels in people with co-occurring HIV and HCV (HIV/HCV) vs. HIV alone, and evaluated the impact of HCV direct-acting antiviral (DAA) therapy on PCSK9. DESIGN: A prospective, observational cohort study. METHODS: Thirty-five adults with HIV/HCV and 37 with HIV alone were evaluated, all with HIV virologic suppression and without documented cardiovascular disease. Circulating PCSK9 and inflammatory biomarkers were measured at baseline and following HCV treatment or at week 52 (for HIV alone) and compared using Wilcoxon tests and Spearman correlations. RESULTS: At baseline, PCSK9 trended higher in HIV/HCV vs. HIV alone (307 vs. 284 ng/ml, P  = 0.06). Twenty-nine participants with HIV/HCV completed DAA therapy with sustained virologic response. PCSK9 declined from baseline to posttreatment 1 (median 7.3 weeks after end of therapy [EOT]) and posttreatment 2 (median 43.5 weeks after EOT), reaching levels similar to HIV alone; median within-person reduction was -60.5 ng/ml ( P  = 0.003) and -55.6 ng/ml ( P  = 0.02), respectively. Decline in PCSK9 correlated with decline in soluble (s)E-selectin and sCD163 ( r  = 0.64, P  = 0.002; r  = 0.58, P  = 0.008, respectively), but not with changes in LDL-C or other biomarkers. No significant change in PCSK9 occurred in the HIV alone group over 52 weeks. CONCLUSION: PCSK9 declined with DAA therapy in participants with HIV/HCV, correlating with declines in several inflammatory biomarkers but not LDL-C. Elevated PCSK9 with HCV may be linked to particular HCV-associated inflammatory pathways more so than cholesterol homeostasis.


Assuntos
Infecções por HIV , Hepatite C Crônica , Hepatite C , Adulto , Humanos , Pró-Proteína Convertase 9 , Antivirais/uso terapêutico , Hepacivirus , LDL-Colesterol , Estudos Prospectivos , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Pró-Proteína Convertases/metabolismo , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Inflamação/complicações , Biomarcadores
2.
Apunts, Med. esport (Internet) ; 58(220)October - December 2023. tab
Artigo em Inglês | IBECS | ID: ibc-226538

RESUMO

The aim of this study was to determine associations between workload, myosin isoforms, and performance in professional basketball, by following the progress of a professional basketball team over four consecutive seasons. Thirty male professional basketball players (age, 27.6 ± 4.1 years;height, 200.1 ± 9.4 cm;weight, 98.5 ± 12.6 kg) from an elite professional basketball team participated in this retrospective observational study. To analyze muscle response and which types of fiber were most involved, fast and myosin in serum were evaluated from three blood samples taken during the season, using enzyme-linked immunosorbent assay (ELISA). Parameters recorded were: exposure time,. Slow and fast myosins for muscle responses. Competitions won, ranking, and mean points scored for performance. Average values per season analysed were 280.1 ± 58 h of exposure to practice,1440.58±533.46µlmol/L of fast and 1178.75±427.75 µmol/L of slow myosin. Performance, assessed as team ranking was 6879.5 ± 985.37 u.a. per season and 90.72±2.79 u.a. per game, winning 7 competitions. Large negative relationships could be observed between slow myosins and exposure time (rho=−0.63;p=.02); There were possible associations between slow myosins and player mean performance per game (R2=0.98;p<.01) and team performance outcomes achieved (R2=0.83;p = 01) during these four seasons. Higher slow serum myosin values could be related to higher exposure time, and lower slow serum myosin values could be associated with better player and team performance. (AU)


Assuntos
Humanos , Masculino , Adulto Jovem , Adulto , Equipamentos Esportivos , Basquetebol/fisiologia , Miosinas/metabolismo , Miosinas/fisiologia , 51654 , Estudos Retrospectivos , Espanha
3.
Cancers (Basel) ; 15(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37568632

RESUMO

The study presents 'G4-QuadScreen', a user-friendly computational tool for identifying MTDLs against G4s. Also, it offers a few hit MTDLs based on in silico and in vitro approaches. Multi-tasking QSAR models were developed using linear discriminant analysis and random forest machine learning techniques for predicting the responses of interest (G4 interaction, G4 stabilization, G4 selectivity, and cytotoxicity) considering the variations in the experimental conditions (e.g., G4 sequences, endpoints, cell lines, buffers, and assays). A virtual screening with G4-QuadScreen and molecular docking using YASARA (AutoDock-Vina) was performed. G4 activities were confirmed via FRET melting, FID, and cell viability assays. Validation metrics demonstrated the high discriminatory power and robustness of the models (the accuracy of all models is ~>90% for the training sets and ~>80% for the external sets). The experimental evaluations showed that ten screened MTDLs have the capacity to selectively stabilize multiple G4s. Three screened MTDLs induced a strong inhibitory effect on various human cancer cell lines. This pioneering computational study serves a tool to accelerate the search for new leads against G4s, reducing false positive outcomes in the early stages of drug discovery. The G4-QuadScreen tool is accessible on the ChemoPredictionSuite website.

4.
AIDS Behav ; 27(12): 4041-4051, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37401993

RESUMO

The COVID-19 pandemic had a significant impact on vulnerable populations, including people living with HIV. California implemented a coronavirus lockdown (stay-at-home order) in March 2020, which ended in January 2021. We evaluated the pandemic's impact on both clinical outcomes of HIV RNA viral load (VL) and retention rate in a randomized clinical trial conducted from May 2018 to October 2020. The intervention group took co-encapsulated antiretrovirals (ARVs) with ingestible sensor (IS) pills from baseline through week 16. The IS system has the capacity to monitor adherence in real-time using a sensor patch, a mobile device, and supporting software. Both the IS and usual care (UC) groups were followed monthly for 28 weeks. Longitudinal mixed-effects models with random intercept and slope (RIAS) were used to fit log VL and self-reported adherence. The sample size of the study was 112 (54 in IS). Overall, the retention rate at week 28 was 86%, with 90% before the lockdown and 83% after the lockdown. The lockdown strengthened the associations between adherence and VL. Before the lockdown, a 10% increase in adherence was associated with a 0.2 unit decrease in log VL (ß = -1.88, p = 0.004), while during the lockdown, the association was a 0.41-unit decrease (ß = -2.27, p = 0.03). The pandemic did not have a significant impact on our adherence-focused intervention. Our findings regarding the intervention effect remain valid. TRIAL REGISTRATION NUMBER: NCT02797262. Date registration: September 2015.


Assuntos
COVID-19 , Infecções por HIV , Humanos , COVID-19/epidemiologia , Pandemias , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Controle de Doenças Transmissíveis , Antirretrovirais/uso terapêutico , Carga Viral , Adesão à Medicação
5.
Sensors (Basel) ; 23(11)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37300079

RESUMO

Applications of MEMS-based sensing technology are beneficial and versatile. If these electronic sensors integrate efficient processing methods, and if supervisory control and data acquisition (SCADA) software is also required, then mass networked real-time monitoring will be limited by cost, revealing a research gap related to the specific processing of signals. Static and dynamic accelerations are very noisy, and small variations of correctly processed static accelerations can be used as measurements and patterns of the biaxial inclination of many structures. This paper presents a biaxial tilt assessment for buildings based on a parallel training model and real-time measurements using inertial sensors, Wi-Fi Xbee, and Internet connectivity. The specific structural inclinations of the four exterior walls and their severity of rectangular buildings in urban areas with differential soil settlements can be supervised simultaneously in a control center. Two algorithms, combined with a new procedure using successive numeric repetitions designed especially for this work, process the gravitational acceleration signals, improving the final result remarkably. Subsequently, the inclination patterns based on biaxial angles are generated computationally, considering differential settlements and seismic events. The two neural models recognize 18 inclination patterns and their severity using an approach in cascade with a parallel training model for the severity classification. Lastly, the algorithms are integrated into monitoring software with 0.1° resolution, and their performance is verified on a small-scale physical model for laboratory tests. The classifiers had a precision, recall, F1-score, and accuracy greater than 95%.


Assuntos
Algoritmos , Software , Aceleração , Internet , Desenho de Equipamento
6.
Front Immunol ; 14: 1154108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37234172

RESUMO

MRGPRX2, a G-protein-coupled-seven transmembrane domain receptor, is mainly expressed in mast cells and neurons and is involved in skin immunity and pain. It is implicated in the pathophysiology of non-IgE-mediated immediate hypersensitivity and has been related to adverse drug reactions. Moreover, a role has been proposed in asthma, atopic dermatitis, contact dermatitis, and chronic spontaneous urticaria. Although it has a prominent role in disease, its signaling transduction is poorly understood. This study shows that MRGPRX2 activation with substance P increased Lysyl t-RNA synthetase (LysRS) translocation to the nucleus. LysRS is a moonlighting protein with a dual role in protein translation and IgE signaling in mast cells. Upon allergen- IgE-FcεRI crosslinking, LysRS is translocated to the nucleus and activates microphthalmia-associated transcription factor (MITF) activity. In this study, we found that MRGPRX2 triggering led to MITF phosphorylation and increased MITF activity. Therefore, overexpression of LysRS increased MITF activity after MRGPRX2 activation. MITF silencing reduced MRGPRX2-dependent calcium influx and mast cell degranulation. Furthermore, a MITF pathway inhibitor, ML329, impaired MITF expression, calcium influx, and mast cell degranulation. Moreover, drugs such as atracurium, vancomycin, and morphine, reported to induce MRGPRX2-dependent degranulation, increased MITF activity. Altogether, our data show that MRGPRX2 signaling enhances MITF activity, and its abrogation by silencing or inhibition resulted in defective MRGPRX2 degranulation. We conclude that MRGPRX2 signaling involves the LysRS and MITF pathway. Thus, MITF and MITF-dependent targets may be considered therapeutic approaches to treat pathologies where MRGPRX2 is implicated.


Assuntos
Lisina-tRNA Ligase , Lisina-tRNA Ligase/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Cálcio/metabolismo , Fator de Transcrição Associado à Microftalmia/metabolismo , Transdução de Sinais , Mastócitos
7.
Int J Mol Sci ; 24(4)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36834926

RESUMO

Activating mutations in KIT (CD117) have been associated with several diseases, including gastrointestinal stromal tumors and mastocytosis. Rapidly progressing pathologies or drug resistance highlight the need for alternative treatment strategies. Previously, we reported that the adaptor molecule SH3 binding protein 2 (SH3BP2 or 3BP2) regulates KIT expression at the transcriptional level and microphthalmia-associated transcription factor (MITF) expression at the post-transcriptional level in human mast cells and gastrointestinal stromal tumor (GIST) cell lines. Lately, we have found that the SH3BP2 pathway regulates MITF through miR-1246 and miR-5100 in GIST. In this study, miR-1246 and miR-5100 were validated by qPCR in the SH3BP2-silenced human mast cell leukemia cell line (HMC-1). MiRNA overexpression reduces MITF and MITF-dependent target expression in HMC-1. The same pattern was observed after MITF silencing. In addition, MITF inhibitor ML329 treatment reduces MITF expression and affects the viability and cell cycle progression in HMC-1. We also examine whether MITF downregulation affected IgE-dependent mast cell degranulation. MiRNA overexpression, MITF silencing, and ML329 treatment reduced IgE-dependent degranulation in LAD2- and CD34+-derived mast cells. These findings suggest MITF may be a potential therapeutic target for allergic reactions and deregulated KIT mast-cell-mediated disorders.


Assuntos
Leucemia de Mastócitos , MicroRNAs , Fator de Transcrição Associado à Microftalmia , Humanos , Morte Celular/genética , Regulação para Baixo , Tumores do Estroma Gastrointestinal/metabolismo , Tumores do Estroma Gastrointestinal/patologia , Imunoglobulina E/metabolismo , Leucemia de Mastócitos/metabolismo , Mastócitos/metabolismo , Fator de Transcrição Associado à Microftalmia/metabolismo , MicroRNAs/genética
9.
Cancer Gene Ther ; 30(2): 245-255, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36241703

RESUMO

Gastrointestinal stromal tumors (GISTs) are the most common neoplasms of mesenchymal origin, and most of them emerge due to the oncogenic activation of KIT or PDGFRA receptors. Despite their relevance in GIST oncogenesis, critical intermediates mediating the KIT/PDGFRA transforming program remain mostly unknown. Previously, we found that the adaptor molecule SH3BP2 was involved in GIST cell survival, likely due to the co-regulation of the expression of KIT and Microphthalmia-associated transcription factor (MITF). Remarkably, MITF reconstitution restored KIT expression levels in SH3BP2 silenced cells and restored cell viability. This study aimed to analyze MITF as a novel driver of KIT transforming program in GIST. Firstly, MITF isoforms were characterized in GIST cell lines and GIST patients' samples. MITF silencing decreases cell viability and increases apoptosis in GIST cell lines irrespective of the type of KIT primary or secondary mutation. Additionally, MITF silencing leads to cell cycle arrest and impaired tumor growth in vivo. Interestingly, MITF silencing also affects ETV1 expression, a linage survival factor in GIST that promotes tumorigenesis and is directly regulated by KIT signaling. Altogether, these results point to MITF as a key target of KIT/PDGFRA oncogenic signaling for GIST survival and tumor growth.


Assuntos
Tumores do Estroma Gastrointestinal , Humanos , Tumores do Estroma Gastrointestinal/patologia , Fator de Transcrição Associado à Microftalmia/genética , Fator de Transcrição Associado à Microftalmia/metabolismo , Transdução de Sinais , Mutação , Transformação Celular Neoplásica , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo
10.
Magn Reson Imaging ; 95: 27-38, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36265696

RESUMO

Brain structural changes in HIV identified by voxel-based morphometry (VBM) alone could arise from a variety of causes that are difficult to distinguish without further information, such as cortical thickness (CT), gyrification index (GI) or sulcal depth (SD). Hence, our goal was to assess these additional metrics in HIV using high-resolution 3D T1-weighted images and investigate if surface-based morphometric (SBM) analysis would reveal significant changes in the gray matter (GM) and white matter (WM) volumes combined with alterations in cortical thickness (CT), gyrification index (GI), sulcal depth (SD). T1-w magnetization-prepared-rapid-acquisition gradient-echo (MP-RAGE) scans were acquired in 27 HIV-infected individuals on antiretroviral therapy (ART) and 15 HIV-uninfected healthy controls using a 3T MRI scanner equipped with a 16-channel head "receive" and a quadrature body "transmit" coil. Voxel-based and surface-based morphometric analyses were performed using the MATLAB based SPM Computational Anatomy Toolbox (CAT12.7(1700)). HIV-infected patients showed significantly altered GM and WM volumes, CT, GI, and SD, in multiple brain regions. This study showed the association of altered GM and WM volumes in local brain regions with the changes in region-wise CT, GI and SD measures of HIV-infected patients, especially in the parahippocampal and middle frontal regions as compared to uninfected healthy controls. The outcome of this study suggests that the findings of VBM may not necessarily indicate the volumetric shrinkage or increase alone, but might also be due to altered CT, GI, or SD. Correlation analysis showed a significantly accelerated gray matter loss with age in HIV-infected individuals compared to uninfected healthy controls.


Assuntos
Infecções por HIV , Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Infecções por HIV/diagnóstico por imagem , Infecções por HIV/tratamento farmacológico
11.
Cancers (Basel) ; 14(24)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36551682

RESUMO

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. Gain of function in receptor tyrosine kinases type III, KIT, or PDGFRA drives the majority of GIST. Previously, our group reported that silencing of the adaptor molecule SH3 Binding Protein 2 (SH3BP2) downregulated KIT and PDGFRA and microphthalmia-associated transcription factor (MITF) levels and reduced tumor growth. This study shows that SH3BP2 silencing also decreases levels of ETV1, a required factor for GIST growth. To dissect the SH3BP2 pathway in GIST cells, we performed a miRNA array in SH3BP2-silenced GIST cell lines. Among the most up-regulated miRNAs, we found miR-1246 and miR-5100 to be predicted to target MITF and ETV1. Overexpression of these miRNAs led to a decrease in MITF and ETV1 levels. In this context, cell viability and cell cycle progression were affected, and a reduction in BCL2 and CDK2 was observed. Interestingly, overexpression of MITF enhanced cell proliferation and significantly rescued the viability of miRNA-transduced cells. Altogether, the KIT-SH3BP2-MITF/ETV1 pathway deserves to be considered in GIST cell survival and proliferation.

12.
EBioMedicine ; 86: 104330, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36372731

RESUMO

BACKGROUND: Co-encapsulated antiretrovirals (ARVs) with ingestible sensor (IS) has the capacity to monitor adherence in real-time using a sensor patch, a mobile device, and supporting software. We evaluated the acceptability, effectiveness, and sustainability of the IS system with real-time text reminders. METHODS: Participants were recruited from HIV clinics in Los Angeles and were randomised 1:1 to IS or usual care (UC) group. Adherence to ARVs (primary outcome) was measured by IS system (IS group only), plasma ARV concentration, and self-report. IS-measured adherence was clustered by group-based trajectory model and was validated by ARV concentration summarized by integrated pharmacokinetic adherence measure (IPAM) score. HIV RNA viral load (VL) was compared between IS and UC group. FINDINGS: A total of 112 (IS = 54, UC = 58) participants who completed baseline with at least one follow-up data collection were included in analyses. Overall satisfaction rate for the IS system was >90%. The IPAM score was higher (0.018, 95% CI: -0.098-0.134, p = 0.75) and VL decayed faster (-0.020, 95% CI: -0.042-0.002, p = 0.08) in the IS group compared with the UC group. The ingestible sensor system was well tolerated by study participants. INTERPRETATION: The IS system was well accepted by participants and its use was associated with improved adherence and lower HIV RNA VL. The findings provide a potentially effective strategy for improving adherence. FUNDING: This work was supported by grant R01-MH110056 from the National Institute of Mental Health (NIMH)/National Institutes of Health (NIH). Y. Wang was in part supported by the NIMH/NIH award T32MH080634. E. Daar was in part supported by the National Center for Advancing Translational Sciences through UCLACTSI Grant UL1TR001881. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.


Assuntos
Infecções por HIV , Adesão à Medicação , Humanos , Infecções por HIV/tratamento farmacológico , Antirretrovirais/uso terapêutico , RNA/uso terapêutico , Carga Viral
13.
Cir Cir ; 90(4): 433-438, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35944421

RESUMO

AIM: Describe our stereotactic brain biopsy (SBB) technique for intra-axial lesions of the posterior fossa, evaluate its effectiveness and safety, and compare them with other series. MATERIAL AND METHODS: Retrospective study in ten consecutive patients, whose variables were age, gender, location of the lesions, clinical, radiological, and histopathological diagnoses, complications, and mortality, for analysis using descriptive statistics and tests of concordance and diagnostic validity. RESULTS: Lesions were pontine in seven cases, and pontomedullary in three occasions, with histopathological diagnoses of four Grade II astrocytomas, two Grade IV astrocytomas, two infectious process, one neuroblastic tumor, and one cavernous malformation, whose frequency differs from the previous reports (χ2 = 0.07). The clinical-radiological concordance was poor (κ = 0.20). The validity of the clinical diagnosis had intermediate values (Sn = 66.7%, Sp = 75%), while radiological studies were more sensitive (Sn = 100%, Sp = 25%). A definitive diagnosis was obtained in all procedures, with no permanent morbidity or mortality because of the surgery. CONCLUSION: The SBB technique for posterior fossa implemented in our hospital shows high diagnostic yield, as well as absolute safety for the patient.


OBJETIVO: Describir nuestra técnica de biopsia cerebral estereotáctica (SBB) para lesiones intraaxiales de fosa posterior, evaluar su eficacia y seguridad y compararlas con otras series. MATERIAL Y MÉTODOS: Estudio retrospectivo en 10 pacientes consecutivos, cuyas variables fueron edad, sexo, localización de las lesiones, diagnósticos clínicos, radiológicos e histopatológicos, complicaciones y mortalidad, para análisis mediante estadística descriptiva y pruebas de concordancia y validez diagnóstica. RESULTADOS: Las lesiones fueron pontinas en 7 casos y pontomedulares en 3 ocasiones, con diagnósticos histopatológicos de 4 astrocitomas grado II, 2 astrocitomas grado IV, 2 procesos infecciosos, 1 tumor neuroblástico y 1 malformación cavernosa, cuya frecuencia difiere de reportes previos (χ2 = 0.07). La concordancia clínico-radiológica fue mala (κ = 0.20). La validez del diagnóstico clínico tuvo valores intermedios (Sn = 66.7%, Sp = 75%), mientras que los estudios radiológicos fueron más sensibles (Sn = 100%, Sp = 25%). Se obtuvo un diagnóstico definitivo en todos los procedimientos, sin morbimortalidad permanente por la cirugía. CONCLUSIÓN: La técnica SBB para fosa posterior implementada en nuestro hospital muestra un alto rendimiento diagnóstico, así como una seguridad absoluta para el paciente.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Astrocitoma/diagnóstico por imagem , Astrocitoma/cirurgia , Biópsia/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Hospitais , Humanos , Estudos Retrospectivos , Técnicas Estereotáxicas
14.
Entramado ; 17(2): 226-242, jul.-dic. 2021. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1360424

RESUMO

RESUMEN La metodología mapa de cadena de valor se ha convertido en una herramienta fundamental para los gerentes debido a su capacidad de diagnosticar procesos empresariales, donde se identifican las actividades que no agregan valor y se proponen alternativas de mejora basadas en distintas técnicas Lean Manufacturing. En el presente artículo, se aplica la herramienta mapa de cadena de valor en los procesos de cosecha y postcosecha de una empresa que se dedica al cultivo y comercialización de piña para el mercado nacional e internacional. Al final de la investigación se identifican desperdicios dentro del proceso como el exceso de manipulación, la falta de capacitación al personal y la ausencia de planes eficientes de mantenimiento de maquinaria. A partir de estas debilidades, se logra definir un plan de acción para la empresa, el cual es simulado utilizando el software Flexsim, donde se contrasta los escenarios "antes" y "después" de la operación con el fin de ilustrar a los gerentes, los beneficios potenciales de la implementación de las propuestas de mejora, en donde se logra establecer una reducción del tiempo de ciclo en aproximadamente un 19% lo que permite aumentar los volúmenes de producción y cumplir con la demanda del cliente final.


ABSTRACT The Value Stream Mapping methodology has become a fundamental tool for managers due to its ability to diagnose business processes, where activities that do not add value are identified and improvement alternatives based on different Lean Manufacturing techniques are proposed. In this article, the Value Stream Mapping tool is applied in the harvesting and postharvest processes of a company that is dedicated to the cultivation and sale of pineapple for the national and international market. At the end of the investigation, waste is identified within the process, such as excessive handling, lack of training for personnel and the absence of efficient machinery maintenance plans. From these weaknesses, it is possible to define an action plan for the company which is simulated using the Flexsim software, where the "before" and "after" scenarios of the operation are contrasted in order to illustrate to the managers, the potential benefits of the implementation of the improvement proposals, where it is possible to establish a reduction in cycle time by approximately 19%, which allows increasing production volumes and meeting the demand of the end customer.


RESUMO A metodologia do Mapeamento do Fluxo de Valor tornou-se uma ferramenta fundamental para os gestores devido a sua capacidade de diagnosticar processos de negócios, onde atividades que não agregam valor são identificadas e alternativas de melhoria são propostas com base em diferentes técnicas de Lean Manufacturing. Neste artigo, a ferramenta de Mapeamento do Fluxo de Valor é aplicada aos processos de colheita e pós-colheita de uma empresa dedicada ao cultivo e comercialização do abacaxi para o mercado nacional e internacional. Ao final da pesquisa, foram identificados resíduos dentro do processo, tais como manuseio excessivo, falta de treinamento de pessoal e a ausência de planos eficientes de manutenção de máquinas. A partir destes pontos fracos, é possível definir um plano de ação para a empresa, que é simulado utilizando o software FlexSim, que contrasta os cenários "antes" e "depois" da operação a fim de ilustrar aos gestores, os benefícios potenciais da implementação das melhorias propostas, onde é possível estabelecer uma redução no tempo de ciclo em aproximadamente 19%, o que permite aumentar os volumes de produção e atender a demanda do cliente final.

15.
Vitae (Medellín) ; 28(2): 1-14, 2021-05-18. Ilustraciones
Artigo em Inglês | LILACS, COLNAL | ID: biblio-1362619

RESUMO

Background: Ayanin (3,7,4'-Tri-O-methylquercetin) and 3,7-Di-O-methylquercetin (DMQ) are the main active metabolites isolated by bioguided fractionation from Croton schiedeanus, species known popularly in Colombia as "almizclillo", which has been studied in experimental models in rats, exerting vasodilator and antihypertensive effects. Also, when the effect of these flavonoids was studied separately, important vasodilation was observed. Objective:To evaluate whether flavonoids from Croton schiedeanus have synergistic vasodilator properties when different combinations are used in isolated aorta rings. Methods: Cumulative concentrations of ayanin (10-8 M - 6x10-5 M or 0.01 µM - 60 µM) were assayed in the absence and presence of an increasing concentration of 3,7-Di-O-methylquercetin (DMQ) (10-8 ­ 3x10-5M or 0.01­30 µM) in isolated rings from Wistar rats, pre-contracted with phenylephrine. The concentration-response curve with the maximal effect was compared with that obtained by Croton schiedeanus whole ethanolic extract (10-6 ­ 3x10-4 g/mL). Also, this combination was assayed in the presence of the nitric oxide synthetase inhibitor L-NAME (10-4 M) and the guanylate cyclase inhibitor methylene blue (10-4 M) to assess the role of the NO/cGMP pathway in this interaction. Results: Ayanin and DMQ display a dual interaction in vascular relaxant response: agonism at higher concentration ranges (10-6 ­ 3x10-5 M or 1­30 µM) and antagonism at lower concentration ranges (10-8 ­ 3x10-7 M or 0.01­0.3 µM). The efficacy at the highest concentration was greater than that obtained by the whole extract (Emax: 98.4% vs. 33.9%). This response was decreased but not reverted in the presence of L-NAME and methylene blue. Thus, the vasodilator effect of this combination does not depend entirely on the NO/cGMP cyclic pathway. Conclusion: The combined use of appropriate concentrations of these flavonoids could represent an advantage over Croton schiedeanus whole extract for vasodilator purposes


Antecedentes: Ayanina (3,7,4'-Tri-O-metilquercetina) y 3,7-Di-O-metilquercetina (DMQ) son los principales metabolitos activos aislados mediante fraccionamiento bioguiado, a partir de Croton schiedeanus, especie conocida popularmente en Colombia como "almizclillo", la cual ha sido estudiada en modelos experimentales en ratas, ejerciendo efectos antihipertensivos y vasodilatadores. Además, al estudiar por separado el efecto de los flavonoides, se observó importante vasodilatación. Objetivo:Evaluar si los principales flavonoides de Croton schiedeanus tienen propiedades vasodilatadoras sinérgicas al utilizar diferentes combinaciones de ellos en anillos de aorta aislados. Metodología: Se analizaron concentraciones acumulativas de ayanina (10-8 M - 6x10-5 M o 0,01 µM - 60 µM) en ausencia y en presencia de concentraciones crecientes de DMQ (10-8 M - 3x10-5 M o 0,01 µM ­ 30 µM) en anillos aislados de ratas Wistar, pre-contraídos con fenilefrina. La curva concentración respuesta obtenida con el efecto máximo, fue comparada con la obtenida con el extracto etanólico de Croton schiedeanus (10-6 - 3x10-4 g/mL). Adicionalmente, esta combinación fue ensayada en presencia del inhibidor de óxido nítrico sintetasa L-NAME (10-4 M) y el inhibidor de guanilato ciclasa, azul de metileno (10-4 M) para evaluar el papel de la vía NO/GMPc en esta interacción. Resultados: Ayanina y DMQ muestran una interacción dual en la respuesta vascular relajante: agonismo en el rango más alto (10-6 M ­ 3x10-5 M o 1 µM ­ 30 µM), y antagonismo en el rango más bajo (10-8 M ­ 3x10-7 M o 0.01 µM ­ 0,3 µM). A altas concentraciones, la eficacia de los flavonoides fue mayor que las obtenidas por el extracto completo (Emáx: 98,4% vs 33,9%). Esta respuesta disminuyó, pero no se revirtió en presencia de L-NAME y azul de metileno. Por lo tanto, el efecto vasodilatador de esta combinación no depende enteramente de la vía NO/GMPc. Conclusión: El uso combinado de las concentraciones apropiadas de estos flavonoides podría representar una ventaja sobre el extracto de Croton schiedeanus, con propósitos vasodilatadores


Assuntos
Humanos , Flavonoides , Croton , Sinergismo Farmacológico , Guanilato Ciclase , Óxido Nítrico
17.
J Allergy Clin Immunol ; 147(5): 1855-1864.e9, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33385443

RESUMO

BACKGROUND: Anaphylaxis is a severe allergic reaction that can be lethal if not treated adequately. The underlying molecular mechanisms responsible for the severity are mostly unknown. OBJECTIVE: This study is based on a clinical case of a patient with extremely severe anaphylaxis to paper wasp venom. This patient has a mutation in the KARS gene, which encodes lysyl-tRNA synthetase (LysRS), a moonlight protein with a canonical function in protein synthesis and a noncanonical function in antigen dependent-FcεRI activation in mast cells. In this study, the objective was to characterize the mutation at the molecular level. METHODS: Analysis of the KARS mutation was carried out using biochemical and functional approaches, cell transfection, Western blot, confocal microscopy, cell degranulation, prostaglandin D2 secretion, and proteases gene transcription. Structural analysis using molecular dynamics simulations and well-tempered metadynamics was also performed. RESULTS: The mutation found, P542R (proline was replaced by arginine at aminoacid 542), affects the location of the protein as we show in biochemical and structural analyses. The mutation resembles active LysRS and causes a constitutive activation of the microphthalmia transcription factor, which is involved in critical mast cell functions such as synthesis of mediators and granule biogenesis. Moreover, the structural analysis provides insights into how LysRS works in mast cell activation. CONCLUSIONS: A link between the aberrant LysRS-P542R function and mast cell-exacerbated activation with increase in proinflammatory mediator release after antigen-IgE-dependent response could be established.


Assuntos
Anafilaxia/genética , Lisina-tRNA Ligase/genética , Adulto , Anafilaxia/imunologia , Animais , Mordeduras e Picadas/complicações , Mordeduras e Picadas/genética , Mordeduras e Picadas/imunologia , Linhagem Celular , Humanos , Lisina-tRNA Ligase/imunologia , Masculino , Mastócitos/imunologia , Fator de Transcrição Associado à Microftalmia/genética , Fator de Transcrição Associado à Microftalmia/imunologia , Mutação , Ratos , Vespas
18.
BMC Med Educ ; 20(1): 446, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213436

RESUMO

BACKGROUND: The Program of Combined Studies in Medicine (PECEM, by its acronym in Spanish) is a program for simultaneous bachelor and doctorate studies (MD/PhD) that enrolls students who show academic excellence and interest in scientific research. The initial doctoral training comprises seven six-month research stays in different laboratories or clinical or computer areas with different high-quality scientific advisors who provide students with a unique experience for their scientific training. Therefore, satisfaction in this stage is decisive for students' performance and physical and psychological health. The aim of the present study was to administer a questionnaire to measure students' satisfaction with their research experience as a service-product bundle. METHODS: Students answered an online questionnaire that evaluated three dimensions: perceived quality of the advisor, skills development, and infrastructure and support. Several satisfiers were also evaluated: recommendation of the advisor to peers, fulfillment of student expectations and satisfaction with the program. Correlations were calculated using Fisher's exact test. The significance was set at p < 0.05. RESULTS: The high quality of the advisor, skills development and guidance during the stay were satisfiers correlated to the students' recommendation of their advisors to their peers and to the fulfillment of the students' scientific expectations. Conversely, skills development and infrastructure and support were satisfiers for a good to excellent experience as a PECEM student. A lack of direct interaction with the advisor's workgroup was related to dissatisfaction. CONCLUSIONS: The nontangible products of the service, such as a positive interaction between the student, the advisor and the advisor's workgroup as well as support obtained during the research stay, were satisfiers. These data indicate that promoting a fruitful bond between the student and advisor is a priority to ensure the quality of our innovative MD/PhD program.


Assuntos
Medicina , Estudantes de Medicina , Docentes de Medicina , Humanos , Satisfação Pessoal , Inquéritos e Questionários
19.
AIDS Res Hum Retroviruses ; 36(1): 65-74, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31516025

RESUMO

We investigated the use of a system with an ingestible sensor (Proteus Digital Health Feedback system) coencapsulated with antiretrovirals (ARVs) to measure real-time adherence. To assess the safety and impact, if any, coencapsulation might have on ARV concentrations, we evaluated the pharmacokinetics of ARVs coencapsulated with an ingestible sensor for eight commonly used fixed-dose combination ARVs: emtricitabine (FTC)/tenofovir disoproxil fumarate (TDF); FTC/tenofovir alafenamide (TAF); efavirenz (EFV)/FTC/TDF; abacavir (ABC)/lamivudine (3TC); dolutegravir (DTG)/ABC/3TC; rilpivirine (RPV)/TAF/FTC; elvitegravir (EVG)/cobicistat (COBI)/FTC/TAF; and bictegravir (BIC)/FTC/TAF. The steady-state apparent peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) were determined from plasma concentrations measured at predose, 1, 2, 4, and 6 h postdose, and compared with literature values. A total of 49 unique patients on stable regimens for at least 12 weeks with undetectable viral loads were recruited. Cmax and AUC values were not statistically significantly different from literature values for all of the formulations except the Cmax of FTC/TDF, Cmax of BIC, and the Cmax of RPV. In a subsequent evaluation of FTC/TDF and BIC/FTC/TAF using a crossover design, the geometric mean ratio (GMR) between the coencapsulated and the unencapsulated formulations for FTC/TDF were the following: FTC, 84.6% (90% confidence interval [CI] 66.6-107.4) for AUC and 77.5% (60.1-99.9) for Cmax. For tenofovir (TFV), the GMR was 96.2% (90% CI 89.2-103.8) for AUC and 87.3% (64.2-118.7) for Cmax. The GMR for BIC (from the BIC/FTC/TAF formulation) was 98.0% (90% CI 84.5-113.5) for AUC and 89.9% (84.5-95.7) for Cmax. The observed deviation in FTC/TDF (Truvada) may be due to participant characteristics, fasted/fed conditions, and/or random variation and may warrant further investigations with a larger sample size. These findings provide assurance for use of coencapsulated ARVs for future HIV treatment-adherence research.


Assuntos
Fármacos Anti-HIV/farmacocinética , Técnicas Biossensoriais , Monitoramento de Medicamentos/instrumentação , Infecções por HIV/tratamento farmacológico , Monitorização Ambulatorial/instrumentação , Monitorização Ambulatorial/métodos , Adulto , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/sangue , Estudos Cross-Over , Portadores de Fármacos , Composição de Medicamentos , Monitoramento de Medicamentos/métodos , Ingestão de Alimentos , Feminino , Humanos , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Carga Viral
20.
Clin Transl Sci ; 13(1): 189-194, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31536156

RESUMO

Adherence with antiretroviral therapy is important for preventing disease progression and HIV transmission. The co-encapsulated pill sensor system sends a signal through a cutaneous patch and allows real-time monitoring of pill ingestion. A 16-week pilot study used a sensor system in 15 HIV-infected individuals with real-time monitoring of pill-taking with a personalized short message system text. System acceptability was assessed by survey at weeks 4, 8, 12, and 16. Follow-up occurred in 80% of subjects through 8 weeks. The system effectively collected measures of pill ingestion, which triggered text message reminders. Only 2 of 14 participants stated that co-encapsulated pills were "unable to take" or "poorly tolerated." At least 75% of respondents stated at each visit that the patch was very or somewhat comfortable. With regard to text message reminders, only 10-15% of the participants at any visit did not find the messages to be helpful. Larger studies will define the utility of this system to assess antiretroviral adherence relative to standard measures.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Composição de Medicamentos/métodos , Infecções por HIV/tratamento farmacológico , Adesão à Medicação , Monitorização Ambulatorial/métodos , Administração Oral , Adulto , Cápsulas/efeitos adversos , Deglutição , Composição de Medicamentos/instrumentação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Ambulatorial/instrumentação , Satisfação do Paciente , Projetos Piloto , Envio de Mensagens de Texto , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio/instrumentação
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