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1.
Sensors (Basel) ; 23(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37299927

RESUMO

Post-ripening fruits need to be ripened to reach edible conditions, as they are not yet mature enough when picked. Ripening technology is based mainly on temperature control and gas regulation, with the proportion of ethylene being one of the key gas regulation parameters. A sensor's time domain response characteristic curve was obtained through the ethylene monitoring system. The first experiment showed that the sensor has good response speed (maximum of first derivative: 2.01714; minimum of first derivative: -2.01714), stability (xg: 2.42%; trec: 2.05%; Dres: 3.28%), and repeatability (xg: 20.6; trec: 52.4; Dres: 2.31). The second experiment showed that optimal ripening parameters include color, hardness (Change Ⅰ: 88.53%, Change Ⅱ: 75.28%), adhesiveness (Change Ⅰ: 95.29%, Change Ⅱ: 74.72%), and chewiness (Change Ⅰ: 95.18%, Change Ⅱ: 74.25%), verifying the response characteristics of the sensor. This paper proves that the sensor was able to accurately monitor changes in concentration which reflect changes in fruit ripeness, and that the optimal parameters were the ethylene response parameter (Change Ⅰ: 27.78%, Change Ⅱ: 32.53%) and the first derivative parameter (Change Ⅰ: 202.38%, Change Ⅱ: -293.28%). Developing a gas-sensing technology suitable for fruit ripening is of great significance.


Assuntos
Etilenos , Frutas , Frutas/fisiologia , Temperatura , Dureza , Proteínas de Plantas
2.
Acta Clin Croat ; 61(3): 436-448, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37492361

RESUMO

Osteoarthritis (OA) can be treated using either a pharmacological or non-pharmacological approach, or a combination of both. The purpose of the present study was to investigate the efficacy of crystalline glucosamine sulfate (CGS) in patients with knee OA. This open-label prospective study (with a 12-month follow-up) included 111 patients of both genders suffering from knee OA, who attended the Special Hospital for Rheumatic Diseases in Novi Sad, Serbia during the 2011-2013 period. Patients were divided into the experimental (n=52) and the control (n=59) group. While the former was prescribed CGS 1500 mg/day, the latter was treated with nonsteroidal anti-inflammatory drugs (NSAIDs) according to the standard protocol. The efficacy of both treatment modes was assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Lequesne index, along with the radiological findings which involved knee joint space width (JSW) measurements. One year following the initial assessment, all patients reported pain intensity reduction; however, those in the CGS group experienced significantly lower pain intensity when compared with controls. At the end of the study, no reduction in the progression of joint structure damage (p>0.5) was noted in either group. Thus, while CGS demonstrated symptomatic efficacy, it failed to delay the progression of knee OA.


Assuntos
Glucosamina , Osteoartrite do Joelho , Feminino , Humanos , Masculino , Seguimentos , Glucosamina/uso terapêutico , Osteoartrite do Joelho/tratamento farmacológico , Estudos Prospectivos , Resultado do Tratamento
3.
J Cell Physiol ; 236(5): 3234-3243, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33094851

RESUMO

As an oncogene, myelocytomatosis oncogene (MYC) is implicated in the concept of "oncogene addiction," where switching off the oncogene leads to the cell cycle arrest and cell differentiation. However, recent data suggest that MYC also controls the establishment of the tumour microenvironment and that "oncogene addiction" actually has a strong immune background. Evaluation of the MYC role in the immunoediting process led to the speculation that cancer just uses and distorts the physiological mechanism by which MYC normally prevents rapidly proliferating cells from the elicitation of an autoimmune response. Concordantly, elevated levels of MYC and induction of immunosuppressive molecules are observed during the processes of growth and development, tissue repair, placenta development, and so forth, implying that MYC may be involved in saving regular physiologically proliferating cells from the immune system attack. Even more, a growing body of evidence suggests MYC involvement in the shaping of the adaptive immune response, immunological memory development, and establishment of immunotolerance. This paper offers an overview of MYC actions in the context of modulation of the immune response in pathological and physiological conditions. The determination of such a new role for a well-known oncogene opens new perspectives in biomedicine, and consequently, in the treatment of various pathological conditions.


Assuntos
Diferenciação Celular/genética , Neoplasias/genética , Oncogenes/genética , Microambiente Tumoral/imunologia , Animais , Pontos de Checagem do Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Microambiente Tumoral/genética
4.
Sensors (Basel) ; 21(24)2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34960335

RESUMO

Lateral stepping is a motor task that is widely used in everyday life to modify the base of support, change direction, and avoid obstacles. Anticipatory Postural Adjustments (APAs) are often analyzed to describe postural preparation prior to forward stepping, however, little is known about lateral stepping. The aim of the study is to characterize APAs preceding lateral steps and to investigate how these are affected by footwear and lower limb preference. Twenty-two healthy young participants performed a lateral step using both their preferred and non-preferred leg in both barefoot and shod conditions. APA spatiotemporal parameters (size, duration, and speed) along both the anteroposterior and mediolateral axes were obtained through force plate data. APAs preceding lateral stepping showed typical patterns both along the anteroposterior and mediolateral axis. RM-ANOVA highlighted a significant effect of footwear only on medio-lateral APAs amplitude (p = 0.008) and velocity (p = 0.037). No differences were found for the limb preference. APAs in lateral stepping presented consistent features in the sagittal component, regardless of limb/shoe factors. Interestingly, the study observed that footwear induced an increase in the medio-lateral APAs size and velocity, highlighting the importance of including this factor when studying lateral stepping.


Assuntos
Equilíbrio Postural , Sapatos , Humanos , Extremidade Inferior , Orientação Espacial
5.
Entropy (Basel) ; 23(6)2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072438

RESUMO

In this paper, we investigate the multi-criteria decision-making complications under intuitionistic fuzzy hypersoft set (IFHSS) information. The IFHSS is a proper extension of the intuitionistic fuzzy soft set (IFSS) which discusses the parametrization of multi-sub attributes of considered parameters, and accommodates more hesitation comparative to IFSS utilizing the multi sub-attributes of the considered parameters. The main objective of this research is to introduce operational laws for intuitionistic fuzzy hypersoft numbers (IFHSNs). Additionally, based on developed operational laws two aggregation operators (AOs), i.e., intuitionistic fuzzy hypersoft weighted average (IFHSWA) and intuitionistic fuzzy hypersoft weighted geometric (IFHSWG), operators have been presented with their fundamental properties. Furthermore, a decision-making approach has been established utilizing our developed aggregation operators (AOs). Through the established approach, a technique for solving decision-making (DM) complications is proposed to select sustainable suppliers in sustainable supply chain management (SSCM). Moreover, a numerical description is presented to ensure the validity and usability of the proposed technique in the DM process. The practicality, effectivity, and flexibility of the current approach are demonstrated through comparative analysis with the assistance of some prevailing studies.

6.
Scand J Immunol ; 92(3): e12920, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32594535

RESUMO

The maintenance of inner integrity of an organism is founded on the proper performance of two immunity branches, innate and adaptive immune responses. Recently, it became apparent that subset of splenic B cells named marginal zone B cells (MZB cells) exhibits unique developmental and functional features that bridge these two immunity branches. Strategically positioned at the site where blood and lymph are filtered, MZB cells represent a population of sentinels that rapidly proliferate and differentiate into IgM plasmablast cells when encountered with blood-borne, thymus-independent (TI) Ags. Moreover, MZB cells have intrinsic capability to induce potent CD4+ helper T cell response and cytokine production upon stimulation with soluble antigens. Due to their ability to overcome a time gap prior the establishment of the full adaptive response towards pathogens, MZB cells connect and direct innate and adaptive immunity. An additional interesting characteristic of MZB cells is capacity to function as regulatory cells in autoimmune processes. MZB cells may also contribute to the control of autoimmunity via the induction of tolerance by apoptotic cells. Importantly, in the clear association with inflammation and autoimmunity, MZB cells may transform into MALT lymphoma, representing a concurrence point for the infection, immunity and malignancy. This paper presents an insight into the complex biology of marginal zone B cells and their role in intertwining and directing innate and adaptive immune processes at the physiological and pathological level.


Assuntos
Linfócitos B/imunologia , Linfócitos B/metabolismo , Suscetibilidade a Doenças , Homeostase , Baço/imunologia , Baço/metabolismo , Imunidade Adaptativa , Animais , Microambiente Celular/imunologia , Humanos , Ativação Linfocitária/imunologia , Baço/patologia
7.
Health Qual Life Outcomes ; 16(1): 149, 2018 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-30055623

RESUMO

BACKGROUND: The dramatic increase in the prevalence of obesity in developed and developing countries has become a major health care concern. Accordingly, there is growing recognition of the relationship between health-related quality of life (HRQOL) and obesity in the pediatric population. This study aimed to explore the relationship between HRQOL and different indicators of obesity in children aged 7-8 years. METHOD: In total, 182 children participated in this study (mean age 7.71 (0.29) years, 48.91% girls). To assess obesity, an InBody 230 analyzer was used to calculate body mass index (BMI) and body fat percentage (BFP). The proxy version of the KIDSCREEN-27 questionnaire was used to assess HRQOL. RESULTS: Among boys, 17.2% were overweight and 4.3% were obese according to BMI, while in terms of body fat percentage (BFP), the corresponding percentages were 12.9 and 9.7%, respectively. Among girls, the prevalence of overweight and obesity was 11.2 and 9.0% by BMI and 10.1 and 7.9% in terms of BFP, respectively. The analysis of BFP showed a significantly higher score in normal weight boys than in obese boys in the Social Support & Peers domains (KW H-test = 10.472, p = 0.03), while in girls, there were no significant differences between weight categories and any HRQOL dimensions. CONCLUSION: Obesity at 7-8 years of age could negatively affect some HRQOL domains; in particular, obese boys may have low social support and peer functioning.


Assuntos
Obesidade Infantil/psicologia , Qualidade de Vida , Índice de Massa Corporal , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade Infantil/diagnóstico , Obesidade Infantil/epidemiologia , Prevalência , Inquéritos e Questionários
8.
EMBO J ; 29(24): 4118-31, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21113129

RESUMO

Reactive oxygen species (ROS) participate in normal intracellular signalling and in many diseases including cancer and aging, although the associated mechanisms are not fully understood. Forkhead Box O (FoxO) 3 transcription factor regulates levels of ROS concentrations, and is essential for maintenance of hematopoietic stem cells. Here, we show that loss of Foxo3 causes a myeloproliferative syndrome with splenomegaly and increased hematopoietic progenitors (HPs) that are hypersensitive to cytokines. These mutant HPs contain increased ROS, overactive intracellular signalling through the AKT/mammalian target of rapamycin signalling pathway and relative deficiency of Lnk, a negative regulator of cytokine receptor signalling. In vivo treatment with ROS scavenger N-acetyl-cysteine corrects these biochemical abnormalities and relieves the myeloproliferation. Moreover, enforced expression of Lnk by retroviral transfer corrects the abnormal expansion of Foxo3(-/-) HPs in vivo. Our combined results show that loss of Foxo3 causes increased ROS accumulation in HPs. In turn, this inhibits Lnk expression that contributes to exaggerated cytokine responses that lead to myeloproliferation. Our findings could explain the mechanisms by which mutations that alter Foxo3 function induce malignancy. More generally, the work illustrates how deregulated ROS may contribute to malignant progression.


Assuntos
Fatores de Transcrição Forkhead/deficiência , Transtornos Mieloproliferativos/patologia , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Acetilcisteína/uso terapêutico , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteína Forkhead Box O3 , Sequestradores de Radicais Livres/uso terapêutico , Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Membrana , Camundongos , Camundongos Knockout , Transtornos Mieloproliferativos/tratamento farmacológico , Transdução de Sinais , Esplenomegalia/patologia
9.
Eur J Clin Pharmacol ; 69(4): 859-65, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23093041

RESUMO

PURPOSE: The aim of the study was to develop a population pharmacokinetic (PK) model for clearance of bisoprolol in patients with congestive heart failure (CHF). METHODS: Parameters associated with the plasma concentrations of bisoprolol at steady-state were analyzed in 61 patients (mean age 66.21 ± 9.49 years; mean total body weight 8.90 ± 12.26 kg) with CHF using non-linear mixed-effect modeling (NONMEM). A validation set of 17 patients with heart failure was used to estimate the predictive performance of the pharmacokinetic model. RESULTS: The typical mean value for bisoprolol clearance (CL), estimated by the base model (without covariates), in our population was 11.4 l h(-1). In the full model, covariates such as bisoprolol total daily dose (DD) and creatinine clearance were included. The final regression model for the clearance of bisoprolol was the following: CL (l h(-1)) = 4.68 + 0.859 * DD. CONCLUSION: The derived PK model describes the clearance of bisoprolol in patients with CHF, showing that the total daily dose of bisoprolol is the most important covariate. This finding will provide the basis for future PK studies on beta blockers in this specific patient population and lead to better overall management of heart failure.


Assuntos
Antagonistas de Receptores Adrenérgicos beta 1/farmacocinética , Bisoprolol/farmacocinética , Insuficiência Cardíaca/tratamento farmacológico , Modelos Biológicos , Antagonistas de Receptores Adrenérgicos beta 1/administração & dosagem , Antagonistas de Receptores Adrenérgicos beta 1/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Bisoprolol/administração & dosagem , Bisoprolol/uso terapêutico , Doença Crônica , Feminino , Insuficiência Cardíaca/sangue , Humanos , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade
10.
Coll Antropol ; 37 Suppl 2: 171-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23914505

RESUMO

The aim of the present study was to analyze differences in motor and cognitive abilities of children depending on their value in quantitative indicators of Body Mass Index (BMI) and subcutaneous fatty tissue. The study sample consisted of overall 910 boys and girls, aged 11 to 14, all from elementary schools in Vojvodina (Serbia). Six anthropometric, eight motor and one cognitive variable were analyzed to identify quantitative and qualitative differences in motor and cognitive functioning of children. Children were divided into three groups within gender based on their body mass index calculated and subcutaneous fatty tissue measured. The results obtained from the study indicate the existence of differences in motor and only partly in intellectual abilities between groups of subjects. The greatest differences between the clusters were found in the level of coordination of the entire body, and the static strength of arms and shoulders.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Índice de Massa Corporal , Desenvolvimento Infantil/fisiologia , Cognição/fisiologia , Destreza Motora/fisiologia , Gordura Subcutânea/fisiologia , Adolescente , Criança , Feminino , Humanos , Masculino
11.
Micromachines (Basel) ; 14(8)2023 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-37630099

RESUMO

Ceramics are widely used in microelectronics, semiconductor manufacturing, medical devices, aerospace, and aviation, cutting tools, precision optics, MEMS and NEMS devices, insulating components, and ceramic molds. But the fabrication and machining of the ceramic-based materials by conventional processes are always difficult due to their higher hardness and mechanical properties. Therefore, advanced manufacturing techniques are being preferred for these advanced materials, and out of that, laser-based processes are widely used. The benefits of laser fabrication and machining of ceramics include high precision, reduced thermal damage, non-contact processing, and the ability to work with complex geometries. Laser technology continues to advance, enabling even more intricate and diverse applications for ceramics in a wide range of industries. This paper explains various laser based ceramic processing techniques, such as selective laser sintering and melting, and laser machining techniques, such as laser drilling, etc. Identifying and optimizing the process parameters that influence the output quality of laser processed parts is the key technique to improving the quality, which is also focused on in this paper. It aims to facilitate the researchers by providing knowledge on laser-based manufacturing of ceramics and their composites to establish the field further.

12.
Front Bioeng Biotechnol ; 11: 1261108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38274011

RESUMO

Piezoelectric scaffolds have been recently developed to explore their potential to enhance the bone regeneration process using the concept of piezoelectricity, which also inherently occurs in bone. In addition to providing mechanical support during bone healing, with a suitable design, they are supposed to produce electrical signals that ought to favor the cell responses. In this study, using finite element analysis (FEA), a piezoelectric scaffold was designed with the aim of providing favorable ranges of mechanical and electrical signals when implanted in a large bone defect in a large animal model, so that it could inform future pre-clinical studies. A parametric analysis was then performed to evaluate the effect of the scaffold design parameters with regard to the piezoelectric behavior of the scaffold. The designed scaffold consisted of a porous strut-like structure with piezoelectric patches covering its free surfaces within the scaffold pores. The results showed that titanium or PCL for the scaffold and barium titanate (BT) for the piezoelectric patches are a promising material combination to generate favorable ranges of voltage, as reported in experimental studies. Furthermore, the analysis of variance showed the thickness of the piezoelectric patches to be the most influential geometrical parameter on the generation of electrical signals in the scaffold. This study shows the potential of computer tools for the optimization of scaffold designs and suggests that patches of piezoelectric material, attached to the scaffold surfaces, can deliver favorable ranges of electrical stimuli to the cells that might promote bone regeneration.

14.
Eur J Sport Sci ; 22(3): 354-359, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33896398

RESUMO

ABSTRACTBackground: Postural stability (PS) has an important role in many athletic activities. However, modern dance demands a heightened PS because of the required aesthetic quality and speed of movement. The aim of the present study was to compare the static and dynamic PS of young dancers and participants of other sporting activities.Method: A total of 101 girls (age: 7.91 ± 0.7 year) were divided into a Dance group (N = 53) and a physically active Control group (N = 48). Static PS was assessed with a two-leg standing test on a Force plate, and dynamic PS was assessed with a Körperkoordinationstest für Kinder (KTK) - a walking backwards test on a balance beam.Results: Multivariate analysis of variance showed a general difference between the groups (F = 21.95; p ≤ 0.0001). In static PS, the Dance group was better in Total distance of center of pressure (COP) (p ≤ 0.0001; ES = -1.70), Anterior-posterior oscillation (p ≤ 0.0001; ES = -1.40), Medial-lateral oscillation (p ≤ 0.0001; ES = 1.75) and Length in function of surface (p ≤ 0.0001; ES = -0.98). Both parameters of dynamic stability, the KTK test (p ≤ 0.0001; ES = 1.28) and Motor quotients KTK test (p ≤ 0.0001; ES = 1.45), were significantly better in the Dance group.Conclusion: The results from the present study indicate that children girls who participate mostly in dance develop better static and dynamic PS than children girls who participate in other sport activities. These findings underline the importance of training modification toward the improvement of PS in dance.


Assuntos
Dança , Criança , Feminino , Humanos , Movimento , Equilíbrio Postural , Caminhada
15.
Front Psychol ; 13: 844678, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35496239

RESUMO

Study in the period of coronavirus disease 2019 (COVID-19) lockdown and the effect of different exercise training programs on the quality of life (QoL) dimension are limited. This randomized control study as a part of which the impact of an 8-week neuromuscular training program on the 90 healthy young individuals' QoL after COVID-19 lockdown was assessed using a short form of the WHOQOL-BREF questionnaire comprising of four domains (physical health, psychological health, social relations, and the environment). The intervention group (NT) (n = 47) took part in a neuromuscular training program consisting of dynamic neuromuscular stabilization and whole-body vibration training. In contrast, the control group (CG) (n = 43) did not participate in any programmed physical activity. From pre- to post-intervention test, the NT group significantly and substantially improved [mean change (95% CI)] all the QoL domains, physical for 12.78 scores (8.89, 16.64), psychological for 13.12 scores (9.51, 16.74), social relationships for 20.57 scores (16.12, 25.02), and environmental for 24.40 scores (21.45, 27.35). These results suggest that the NT program could enhance QoL in young and healthy participants following COVID-19 lockdown.

16.
Biomed Res Int ; 2022: 7728277, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36277881

RESUMO

Rotator cuff disease, external and internal impingement syndromes, low shoulder stability, various types of trauma, and overuse injuries are all related to sports activities. In order to check symptoms in patients with disability and shoulder pain, clinicians use different methods and diagnostic imaging assessment. The research is aimed at evaluating whether there is a difference between provocation function tests (PFT) and ultrasonographic (US) testing of muscles within the rotator cuff in elite collegiate athletes. Patients (n = 184) were recruited from university team sports selections and tested with a standardized US examination of the shoulder and five PFTs (Speed's test, Neer's test, Hawkins test, lift-off test, Yergason's test). Based on the VAS pain assessment scale, 60 subjects had some pain, which was taken for further processing in the work (124 subjects did not have the presence of pain and were excluded from further processing). The US examination was conducted using Voluson 730 apparatus, by a linear probe, with the frequency in the range of 6-12 MHz. The chi-square test showed significant differences between PFT and the occurrence of shoulder muscle tendinitis for the following variables: Speed's test and subscapularis tendinitis (p = 0.02) and Speed's test and infraspinatus tendinitis (p = 0.01); Neer test and biceps brachii caput longum tendinitis (p = 0.01), Neer test and supraspinatus tendinitis (p = 0.02) and Neer test and infraspinatus tendinitis (p = 0.01); lift-off test and subscapularis tendinitis (p = 0.05); and Yergason's test and biceps brachii caput longum tendinitis (p = 0.03) and Yergason's test and subscapitis tendinitis (p = 0.01). The greatest effect of differences was observed in Neer's test and biceps brachii caput longum tendinitis (φ = 0.60), while the other effects can be described as medium and small in most cases. It can be concluded that functional tests are good predictors of soft tissue changes in the muscles of the rotator cuff of the shoulder. Further monitoring and analysis are needed on a larger number of athletes.


Assuntos
Lesões do Manguito Rotador , Tendinopatia , Humanos , Manguito Rotador/diagnóstico por imagem , Universidades , Lesões do Manguito Rotador/diagnóstico , Dor de Ombro , Atletas
17.
Blood ; 114(12): 2448-58, 2009 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-19628709

RESUMO

Deregulated c-MYC is found in a variety of cancers where it promotes proliferation as well as apoptosis. In many hematologic malignancies, enhanced NF-kappaB exerts prosurvival functions. Here we investigated the role of NF-kappaB in mouse and human c-MYC-transformed lymphomas. The NF-kappaB pathway is extinguished in murine lymphoma cells, and extrinsic stimuli typically inducing NF-kappaB activity fail to activate this pathway. Genetic activation of the NF-kappaB pathway induces apoptosis in these cells, whereas inhibition of NF-kappaB by an IkappaBalpha superrepressor provides a selective advantage in vivo. Furthermore, in human Burkitt lymphoma cells we find that NF-kappaB activation induces apoptosis. NF-kappaB up-regulates Fas and predisposes to Fas-induced cell death, which is caspase-8 mediated and can be prevented by CFLAR overexpression. We conclude that c-MYC overexpression sensitizes cells to NF-kappaB-induced apoptosis, and persistent inactivity of NF-kappaB signaling is a prerequisite for MYC-mediated tumorigenesis. We could also show that low immunogenicity and Fas insensitivity of MYC-driven lymphoma cells are reversed by activation of NF-kappaB. Our observations provide a molecular explanation for the described absence of the NF-kappaB signaling in Burkitt lymphoma and question the applicability of NF-kappaB inhibitors as candidates for treatment of this cancer.


Assuntos
Apoptose , Linfoma de Burkitt/patologia , Quinase I-kappa B/fisiologia , Linfoma de Células B/patologia , NF-kappa B/fisiologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Supressoras de Tumor/fisiologia , Animais , Western Blotting , Linfoma de Burkitt/metabolismo , Caspases/metabolismo , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Ensaio de Desvio de Mobilidade Eletroforética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Linfoma de Células B/metabolismo , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas c-myc/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Transfecção
18.
Circ Res ; 104(10): 1151-9, 2009 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-19407242

RESUMO

Previous work has shown that c-Myc is required for adequate vasculogenesis and angiogenesis. To further investigate the contribution of Myc to these processes, we conditionally expressed c-Myc in embryonic endothelial cells using a tetracycline-regulated system. Endothelial Myc overexpression resulted in severe defects in the embryonic vascular system. Myc-expressing embryos undergo widespread edema formation and multiple hemorrhagic lesions. They die between embryonic days 14.5 and 17.5. The changes in vascular permeability are not caused by deficiencies in vascular basement membrane composition or pericyte coverage. However, the overall turnover of endothelial cells is elevated as is revealed by increased levels of both proliferation and apoptosis. Whole-mount immunohistochemical analysis revealed alterations in the architecture of capillary networks. The dermal vasculature of Myc-expressing embryos is characterized by a reduction in vessel branching, which occurs despite upregulation of the proangiogenic factors vascular endothelial growth factor-A and angiopoietin-2. Thus, the net outcome of an excess of vascular endothelial growth factor-A and angiopoietin-2 in the face of an elevated cellular turnover appears to be a defect in vascular integrity.


Assuntos
Permeabilidade da Membrana Celular/fisiologia , Endotélio Vascular/embriologia , Endotélio Vascular/metabolismo , Neovascularização Fisiológica/fisiologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Angiopoietina-2/metabolismo , Animais , Linhagem Celular , Endotélio Vascular/citologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Animais , Receptor TIE-2/metabolismo , Regulação para Cima/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Mol Neurobiol ; 58(8): 4169-4177, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33954904

RESUMO

MYC is well known as a potent oncogene involved in regulating cell cycle and metabolism. Augmented MYC expression leads to cell cycle dysregulation, intense cell proliferation, and carcinogenesis. Surprisingly, its increased expression in neurons does not induce their proliferation, but leads to neuronal cell death and consequent development of a neurodegenerative phenotype. Interestingly, while cancer and neurodegenerative diseases such as Alzheimer's disease are placed at the opposite sides of cell division spectrum, both start with cell cycle dysregulation and stimulation of proliferation. It seems that MYC action directed toward neuron cell proliferation and neural tissue repair collides with evolutional loss of regenerative capacity of CNS neurons in order to strengthen synaptic structure, to protect our cognitive abilities and therefore character. Accordingly, there are abundant mechanisms that block its expression and action specifically in the brain. Moreover, while MYC expression in brain neurons during neurodegenerative processes is related to their death, there are obvious evidences that MYC action after physical injury is beneficial in case of peripheral nerve recovery. MYC might be a useful tool to repair brain cells upon development of neurodegenerative disease or CNS trauma, including stroke and traumatic brain and spinal cord injury, as even imperfect axonal growth and regeneration strategies will likely be of profound benefit. Understanding complex control of MYC action in the brain might have important therapeutic significance, but also it may contribute to the comprehension of development of neurodegenerative diseases.


Assuntos
Encéfalo/metabolismo , Doenças Neurodegenerativas/metabolismo , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Encéfalo/patologia , Morte Celular/fisiologia , Humanos , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Neurônios/patologia , Proteínas Proto-Oncogênicas c-myc/genética
20.
Int Rev Immunol ; 40(4): 255-267, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32631119

RESUMO

Ectopic lymphoid structures (ELS) or tertiary lymphoid organs are structures with the organization similar to the one of secondary lymphoid organs, formed in non-lymphoid tissues. They are considered to be an important site for the lymphocytic physiological and pathological role in conditions such are chronic infections, autoimmune diseases, cancer, and allograft rejection. Although similar to the secondary lymphoid tissues, the initiation of ELS formation is not preprogramed and requires chronic inflammation, expression of homeostatic chemokines, and lymphotoxin beta receptor activation. Importantly, while ELS formation may be considered beneficiary in antimicrobial and antitumor immunity, the persistence of these active lymphoid structures within the tissue increase the chance for development of autoimmunity and lymphoma. This paper is providing an overview of biological mechanisms involved in ELS formation, as well as the overview of the pathophysiological role of these structures. In addition, the paper discusses the possibility to therapeutically target ELS formation, bearing in mind their bivalent nature and role in different pathophysiological conditions.


Assuntos
Doenças Autoimunes , Infecções , Estruturas Linfoides Terciárias , Autoimunidade , Quimiocinas , Humanos , Tecido Linfoide
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