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1.
J Biol Chem ; 300(1): 105548, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38092148

RESUMO

Therapeutic mRNAs are generated using modified nucleotides, namely N1-methylpseudouridine (m1Ψ) triphosphate, so that the mRNA evades detection by the immune system. RNA modifications, even at a single-nucleotide position, perturb RNA structure, although it is not well understood how structure and function is impacted by globally modified RNAs. Therefore, we examined the metastasis-associated lung adenocarcinoma transcript 1 triple helix, a highly structured stability element that includes single-, double-, and triple-stranded RNA, globally modified with N6-methyladenosine (m6A), pseudouridine (Ψ), or m1Ψ. UV thermal denaturation assays showed that m6A destabilizes both the Hoogsteen and Watson-Crick faces of the RNA by ∼20 °C, Ψ stabilizes the Hoogsteen and Watson-Crick faces of the RNA by ∼12 °C, and m1Ψ has minimal effect on the stability of the Hoogsteen face of the RNA but increases the stability of the Watson-Crick face by ∼9 °C. Native gel-shift assays revealed that binding of the methyltransferase-like protein 16 to the metastasis-associated lung adenocarcinoma transcript 1 triple helix was weakened by at least 8-, 99-, and 23-fold, respectively, when RNA is globally modified with m6A, Ψ, or m1Ψ. These results demonstrate that a more thermostable RNA structure does not lead to tighter RNA-protein interactions, thereby highlighting the regulatory power of RNA modifications by multiple means.


Assuntos
RNA Longo não Codificante , RNA , Metiltransferases/genética , Metiltransferases/metabolismo , Conformação de Ácido Nucleico , Nucleotídeos , Pseudouridina , RNA/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
2.
Amino Acids ; 56(1): 35, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698213

RESUMO

Chagas disease, caused by the protozoa Trypanosoma cruzi, continues to be a serious public health problem in Latin America, worsened by the limitations in its detection. Given the importance of developing new diagnostic methods for this disease, the present review aimed to verify the number of publications dedicated to research on peptides that demonstrate their usefulness in serodiagnosis. To this end, a bibliographic survey was conducted on the PubMed platform using the keyword "peptide" or "epitope" combined with "Chagas disease" or "Trypanosoma cruzi"; "diagno*" or "serodiagnosis" or "immunodiagnosis", without period restriction. An increasing number of publications on studies employing peptides in ELISA and rapid tests assays was verified, which confirms the expansion of research in this field. It is possible to observe that many of the peptides tested so far originate from proteins widely used in the diagnosis of Chagas, and many of them are part of commercial tests developed. In this sense, as expected, promising results were obtained for several peptides when tested in ELISA, as many of them exhibited sensitivity and specificity values above 90%. Furthermore, some peptides have been tested in several studies, confirming their diagnostic potential. Despite the promising results observed, it is possible to emphasize the need for extensive testing of peptides, using different serological panels, in order to confirm their potential. The importance of producing an effective assay capable of detecting the clinical stages of the disease, as well as new immunogenic antigens that enable new serological diagnostic tools for Chagas disease, is evident.


Assuntos
Doença de Chagas , Ensaio de Imunoadsorção Enzimática , Peptídeos , Trypanosoma cruzi , Doença de Chagas/diagnóstico , Doença de Chagas/imunologia , Doença de Chagas/sangue , Humanos , Trypanosoma cruzi/imunologia , Peptídeos/imunologia , Peptídeos/química , Ensaio de Imunoadsorção Enzimática/métodos , Testes Imunológicos/métodos , Antígenos de Protozoários/imunologia , Antígenos de Protozoários/sangue , Testes Sorológicos/métodos
3.
Microb Cell Fact ; 23(1): 145, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778337

RESUMO

Recombinant multiepitope proteins (RMPs) are a promising alternative for application in diagnostic tests and, given their wide application in the most diverse diseases, this review article aims to survey the use of these antigens for diagnosis, as well as discuss the main points surrounding these antigens. RMPs usually consisting of linear, immunodominant, and phylogenetically conserved epitopes, has been applied in the experimental diagnosis of various human and animal diseases, such as leishmaniasis, brucellosis, cysticercosis, Chagas disease, hepatitis, leptospirosis, leprosy, filariasis, schistosomiasis, dengue, and COVID-19. The synthetic genes for these epitopes are joined to code a single RMP, either with spacers or fused, with different biochemical properties. The epitopes' high density within the RMPs contributes to a high degree of sensitivity and specificity. The RMPs can also sidestep the need for multiple peptide synthesis or multiple recombinant proteins, reducing costs and enhancing the standardization conditions for immunoassays. Methods such as bioinformatics and circular dichroism have been widely applied in the development of new RMPs, helping to guide their construction and better understand their structure. Several RMPs have been expressed, mainly using the Escherichia coli expression system, highlighting the importance of these cells in the biotechnological field. In fact, technological advances in this area, offering a wide range of different strains to be used, make these cells the most widely used expression platform. RMPs have been experimentally used to diagnose a broad range of illnesses in the laboratory, suggesting they could also be useful for accurate diagnoses commercially. On this point, the RMP method offers a tempting substitute for the production of promising antigens used to assemble commercial diagnostic kits.


Assuntos
Epitopos , Escherichia coli , Proteínas Recombinantes , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Humanos , Epitopos/imunologia , Epitopos/genética , Testes Imunológicos/métodos , Animais , COVID-19/diagnóstico
4.
Sensors (Basel) ; 23(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37299925

RESUMO

The next generation of mobile broadband communication, 5G, is seen as a driver for the industrial Internet of things (IIoT). The expected 5G-increased performance spanning across different indicators, flexibility to tailor the network to the needs of specific use cases, and the inherent security that offers guarantees both in terms of performance and data isolation have triggered the emergence of the concept of public network integrated non-public network (PNI-NPN) 5G networks. These networks might be a flexible alternative for the well-known (albeit mostly proprietary) Ethernet wired connections and protocols commonly used in the industry setting. With that in mind, this paper presents a practical implementation of IIoT over 5G composed of different infrastructure and application components. From the infrastructure perspective, the implementation includes a 5G Internet of things (IoT) end device that collects sensing data from shop floor assets and the surrounding environment and makes these data available over an industrial 5G Network. Application-wise, the implementation includes an intelligent assistant that consumes such data to generate valuable insights that allow for the sustainable operation of assets. These components have been tested and validated in a real shop floor environment at Bosch Termotecnologia (Bosch TT). Results show the potential of 5G as an enhancer of IIoT towards smarter, more sustainable, green, and environmentally friendly factories.


Assuntos
Internet das Coisas , Indústrias , Internet , Comunicação , Inteligência
5.
Sensors (Basel) ; 21(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34300415

RESUMO

Industry 4.0, allied with the growth and democratization of Artificial Intelligence (AI) and the advent of IoT, is paving the way for the complete digitization and automation of industrial processes. Maintenance is one of these processes, where the introduction of a predictive approach, as opposed to the traditional techniques, is expected to considerably improve the industry maintenance strategies with gains such as reduced downtime, improved equipment effectiveness, lower maintenance costs, increased return on assets, risk mitigation, and, ultimately, profitable growth. With predictive maintenance, dedicated sensors monitor the critical points of assets. The sensor data then feed into machine learning algorithms that can infer the asset health status and inform operators and decision-makers. With this in mind, in this paper, we present TIP4.0, a platform for predictive maintenance based on a modular software solution for edge computing gateways. TIP4.0 is built around Yocto, which makes it readily available and compliant with Commercial Off-the-Shelf (COTS) or proprietary hardware. TIP4.0 was conceived with an industry mindset with communication interfaces that allow it to serve sensor networks in the shop floor and modular software architecture that allows it to be easily adjusted to new deployment scenarios. To showcase its potential, the TIP4.0 platform was validated over COTS hardware, and we considered a public data-set for the simulation of predictive maintenance scenarios. We used a Convolution Neural Network (CNN) architecture, which provided competitive performance over the state-of-the-art approaches, while being approximately four-times and two-times faster than the uncompressed model inference on the Central Processing Unit (CPU) and Graphical Processing Unit, respectively. These results highlight the capabilities of distributed large-scale edge computing over industrial scenarios.


Assuntos
Internet das Coisas , Inteligência Artificial , Indústrias , Aprendizado de Máquina , Redes Neurais de Computação
6.
Int J Mol Sci ; 22(18)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34575971

RESUMO

BACKGROUND: The tumor immune microenvironment exerts a pivotal influence in tumor initiation and progression. The aim of this study was to analyze the immune context of sporadic and familial adenomatous polyposis (FAP) lesions along the colorectal adenoma-carcinoma sequence (ACS). METHODS: We analyzed immune cell counts (CD3+, CD4+, CD8+, Foxp3+, and CD57+), tumor mutation burden (TMB), MHC-I expression and PD-L1 expression of 59 FAP and 74 sporadic colorectal lesions, encompassing adenomas with low-grade dysplasia (LGD) (30 FAP; 30 sporadic), adenomas with high-grade dysplasia (22 FAP; 30 sporadic), and invasive adenocarcinomas (7 FAP; 14 sporadic). RESULTS: The sporadic colorectal ACS was characterized by (1) a stepwise decrease in immune cell counts, (2) an increase in TMB and MHC-I expression, and (3) a lower PD-L1 expression. In FAP lesions, we observed the same patterns, except for an increase in TMB along the ACS. FAP LGD lesions harbored lower Foxp3+ T cell counts than sporadic LGD lesions. A decrease in PD-L1 expression occurred earlier in FAP lesions compared to sporadic ones. CONCLUSIONS: The colorectal ACS is characterized by a progressive loss of adaptive immune infiltrate and by the establishment of a progressively immune cold microenvironment. These changes do not appear to be related with the loss of immunogenicity of tumor cells, or to the onset of an immunosuppressive tumor microenvironment.


Assuntos
Adenocarcinoma/imunologia , Polipose Adenomatosa do Colo/imunologia , Antígeno B7-H1/genética , Neoplasias Colorretais/imunologia , Microambiente Tumoral/imunologia , Imunidade Adaptativa/imunologia , Adenocarcinoma/complicações , Adenocarcinoma/genética , Adenocarcinoma/patologia , Polipose Adenomatosa do Colo/complicações , Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/imunologia , Complexo CD3/imunologia , Linfócitos T CD4-Positivos/imunologia , Antígenos CD57/imunologia , Linfócitos T CD8-Positivos/imunologia , Contagem de Células , Linhagem da Célula/imunologia , Neoplasias Colorretais/complicações , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Fatores de Transcrição Forkhead/imunologia , Regulação Neoplásica da Expressão Gênica/imunologia , Humanos , Masculino , Pessoa de Meia-Idade
7.
Helicobacter ; 25 Suppl 1: e12739, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32918356

RESUMO

Gastric cancer is still one of the most prevalent and deadliest cancers in the world. Although our knowledge about the disease has progressed extraordinarily, this has not been accompanied by our capacity to effectively treat the disease. In the last years, immunotherapy made its way into the cancer field and was responsible for major changes in the treatment success rates for several cancer types. Although gastric cancer was not among the first successful targets of this type of therapy, the relationship between this type of cancer, immunosurveillance and immunotherapy is now being actively researched. In this article, we review the literature of the past year regarding the relationship between gastric cancer, its immune microenvironment and response to immunotherapy. Published data indicate that the immune microenvironment influences the clinical behaviour of gastric cancer, and is correlated with its histologic and molecular subtypes with an emphasis on the microsatellite- and EBV-positive tumour subgroups. Although the literature regarding response to immunotherapy is scarce, there is good evidence that patient stratification for immunotherapy is going to become a reality in gastric cancer.


Assuntos
Imunoterapia , Neoplasias Gástricas/terapia , Microambiente Tumoral/imunologia , Humanos
8.
Sensors (Basel) ; 20(12)2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32575891

RESUMO

Small-scale farming can benefit from the usage of information and communication technology (ICT) to improve crop and soil management and increase yield. However, in order to introduce digital farming in rural areas, related ICT solutions must be viable, seamless and easy to use, since most farmers are not acquainted with technology. With that in mind, this paper proposes an Internet of Things (IoT) sensing platform that provides information on the state of the soil and surrounding environment in terms of pH, moisture, texture, colour, air temperature, and light. This platform is coupled with computer vision to further analyze and understand soil characteristics. Moreover, the platform hardware is housed in a specifically designed robust casing to allow easy assembly, transport, and protection from the deployment environment. To achieve requirements of usability and reproducibility, the architecture of the IoT sensing platform is based on low-cost, off-the-shelf hardware and software modularity, following a do-it-yourself approach and supporting further extension. In-lab validations of the platform were carried out to finetune its components, showing the platform's potential for application in rural areas by introducing digital farming to small-scale farmers, and help them delivering better produce and increasing income.

9.
Sensors (Basel) ; 19(11)2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31141885

RESUMO

Falls are one of the most common problems in the elderly population. Therefore, each year more solutions for automatic fall detection are emerging. This paper proposes a single accelerometer algorithm for wearable devices that works for three different body locations: chest, waist and pocket, without a calibration step being required. This algorithm is able to be fully executed on a wearable device and no external devices are necessary for data processing. Additionally, a study of the accelerometer sampling rate, that allows the algorithm to achieve a better performance, was performed. The algorithm was validated with a continuous dataset with daily living activities and 272 simulated falls. Considering the trade-off between sensitivity and the number of false alarms the most suitable sampling rate found was 50 Hz. The proposed algorithm was able to achieve a trade-off of no false alarms and 89.5% of fall detection rate when wearing the sensor on the user's waist with a medium sensitivity level of the algorithm. In conclusion, this paper presents a reliable solution for automatic fall detection that can be adapted to different usages and conditions, since it can be used in different body locations and its sensitivity can be adapted to different subjects according to their physical activity level.


Assuntos
Acidentes por Quedas , Algoritmos , Corpo Humano , Dispositivos Eletrônicos Vestíveis , Humanos , Movimento , Curva ROC , Reprodutibilidade dos Testes
11.
Gastric Cancer ; 19(1): 74-84, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25740226

RESUMO

BACKGROUND: Polymorphisms in inflammation-related genes have been associated with a risk of gastric carcinoma (GC). However, the biological mechanisms underlying these associations are still elusive. Our objective was to determine whether chronic inflammation-associated IL1Β signalling, as seen in the context of Helicobacter pylori infection, could be linked to gastric carcinogenesis by modulating the behaviour of gastric epithelial cells. METHODS: The effect of IL1B was assessed by studying the expression and activation status of the IL1Β-activated transcription factors C/EBPß and CREB in GC cell lines. Interaction between CREB and C/EBPß was explored through interference RNA, chromatin immunoprecipitation and chemical inhibition. CREB and C/EBPß expression was analysed in 66 samples of primary GC and in normal gastric mucosa. GC cell growth was analysed in vitro by BrdU incorporation and in vivo employing a chicken embryo chorioallantoic membrane model. RESULTS: We found that IL1B regulates the expression/activation status of both C/EBPß and CREB in GC cells through an ERK1/2-dependent mechanism. Our results show that CREB is a direct transactivator of CEBPB, acting as an upstream effector in this regulatory mechanism. Furthermore, we found CREB to be overexpressed in 94 % of GC samples and significantly associated with C/EBPß expression (P < 0.05). Finally, we demonstrated both in vitro and in vivo that CREB can mediate IL1B-induced GC cell proliferation. CONCLUSIONS: Our results support the hypothesis that the effect of chronic inflammation on gastric carcinogenesis, as seen in the context of genetically susceptible individuals infected with Helicobacter pylori, includes the modulation of signalling pathways that regulate survival mechanisms in epithelial cells. IL1B is able to increase the expression/activation status of CREB and its target gene C/EBPß, which are mandatory for GC cell survival. Our results may help inform new strategies for the prevention and treatment of GC, including the control of chronic inflammation.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Interleucina-1beta/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Embrião de Galinha , Membrana Corioalantoide , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Mucosa Gástrica/metabolismo , Infecções por Helicobacter/metabolismo , Humanos , Interleucina-1beta/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Transdução de Sinais
12.
Rev Port Cardiol ; 2024 Jun 19.
Artigo em Inglês, Português | MEDLINE | ID: mdl-38906521

RESUMO

INTRODUCTION AND OBJECTIVES: The use of loop diuretics is central in managing congestion in heart failure (HF), but their impact on prognosis remains unclear. In euvolemic patients, dose reduction is recommended, but there is no recommendation on their discontinuation. This study aims to assess the impact of loop diuretic discontinuation on the prognosis of outpatients with HF with reduced ejection fraction. METHODS: This retrospective cohort study collected data from medical records of patients followed in an outpatient HF clinic at a university hospital center. Patients were included if they had been on loop diuretics and these were discontinued. Demographic, clinical and laboratory data were collected, and number and type of congestive events during the one-year period after discontinuation were recorded. RESULTS: Among 265 patients on loop diuretics, almost half (129) discontinued them at some point. Patients had optimized medical therapy, low median age, low New York Heart Association class, low B-type natriuretic peptide values, normal blood pressure, controlled heart rate and kidney function within normal limits. Among 122 patients with one year of follow-up, 18 (14.8%) had a congestive event. Fifteen events (83.3%) were low-dose diuretic reinitiation at a scheduled visit. There were only three worsening heart failure events (2.5%) during the one-year period. A significant improvement in kidney function from discontinuation to the one-year follow-up appointment was also observed. CONCLUSIONS: In our cohort, loop diuretic discontinuation was possible and safe in a large proportion of patients. The results should be interpreted with caution and cannot be extrapolated to a broader population of HF patients.

13.
Rev Port Cardiol ; 42(1): 53-59, 2023 01.
Artigo em Inglês, Português | MEDLINE | ID: mdl-36116990

RESUMO

INTRODUCTION: In patients with cryptogenic stroke, one of the most frequently found abnormalities is patent foramen ovale (PFO). Percutaneous 'deviceless' systems based on surgical suture-mediated PFO closure have recently been introduced and show a favorable efficacy and safety profile with clear advantages. OBJECTIVES: To present procedural details of the technique and baseline characteristics of patients who underwent the procedure in our center. METHODS: A single-center prospective observational registry was established between February 2020 and February 2021, to assess the safety, efficacy and possible advantages of a novel percutaneous PFO closure system (NobleStitch® EL). Patient and PFO characteristics as well as technical features were collected for analysis. RESULTS: Twenty-three patients were considered suitable for this technique after transesophageal echocardiography. Their mean age was 51 years and 69.5% were women. Most patients (91.3%) had a history of cryptogenic stroke. PFO closure with the NobleStitch® system was successfully performed in all patients. All procedures were performed under local anesthesia and fluoroscopic monitoring. The mean duration of the procedure was 52 min and median contrast dose used was 187 ml. Median radiation dose absorbed per patient was 61.5 Gy cm2. All patients were discharged asymptomatic 24 hours after the procedure with no peri- or postprocedural complications recorded. CONCLUSION: Suture-mediated PFO closure represents a valid and safe alternative to traditional umbrella-like devices, and is feasible in the majority of PFO anatomies. Follow-up information, results of larger series and clinical trials may possibly validate this technique as the first choice for PFO closure.


Assuntos
Forame Oval Patente , AVC Isquêmico , Dispositivo para Oclusão Septal , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Forame Oval Patente/cirurgia , Forame Oval Patente/complicações , Resultado do Tratamento , Portugal , Cateterismo Cardíaco/métodos , AVC Isquêmico/complicações , Suturas/efeitos adversos , Dispositivo para Oclusão Septal/efeitos adversos
14.
Pathogens ; 12(2)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36839584

RESUMO

Chagas disease remains a neglected disease that is considered to be a public health problem. The early diagnosis of cases is important to improve the prognosis of infected patients and prevent transmission. Serological tests are the method of choice for diagnosis. However, two serological tests are currently recommended to confirm positive cases. In this sense, more sensitive and specific serological tests need to be developed to overcome these current diagnosis problems. This study aimed to develop a new recombinant multiepitope protein for the diagnosis of Chagas disease, hereafter named rTC. The rTC was constructed based on amino acid sequences from different combinations of Trypanosoma cruzi antigens in the same polypeptide and tested using an enzyme-linked immunosorbent assay (ELISA) to detect different types of Chagas disease. rTC was able to discriminate between indeterminate (IND) and cardiac (CARD) cases and cross-reactive diseases, as well as healthy samples, with 98.28% sensitivity and 96.67% specificity, respectively. These data suggest that rTC has the potential to be tested in future studies against a larger serological panel for the diagnosis of Chagas disease.

15.
J Control Release ; 349: 731-743, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35905784

RESUMO

Colorectal cancer (CRC) is a heterogeneous disease with high incidence and mortality worldwide. The efficacy of conventional CRC chemotherapy is hampered by poor drug solubility and bioavailability and suboptimal pharmacokinetic profiles. In this work, camptothecin (CPT), a potent anticancer drug, was loaded into an amphiphilic chitosan modified with PEG and oleic acid, to reduce CRC progression after oral administration. While CPT-loaded micelles presented anticancer activity against HCT116, Caco-2 and HT29 CRC cell lines in vitro, empty micelles demonstrated a safe profile when incubated with human blood cells and colorectal cancer cell lines. In a more complex 3D CRC multicellular spheroid model, CPT-loaded micelles also exhibited a significant effect on the spheroid's metabolic activity and size reduction. Remarkably, in vivo studies performed in a HCT116 xenograft model, showed a significant reduction on the tumor growth during and after treatment with CPT-loaded micelles. Moreover, in a more biological relevant in vivo model of chemically-induced CRC, orally administered CPT-loaded micelles demonstrated a significant reduction on tumor incidence and inflammation signs. The findings here reported indicate that CPT-loaded into chitosan-based micelles, by improving drug solubility, alongside its safety profile for normal tissues, may have a promising role CRC chemotherapy.


Assuntos
Antineoplásicos Fitogênicos , Antineoplásicos , Quitosana , Neoplasias Colorretais , Antineoplásicos/uso terapêutico , Células CACO-2 , Camptotecina , Linhagem Celular Tumoral , Quitosana/uso terapêutico , Neoplasias Colorretais/patologia , Portadores de Fármacos/uso terapêutico , Humanos , Micelas , Ácido Oleico
16.
Helicobacter ; 16 Suppl 1: 38-44, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21896084

RESUMO

Gastric cancer (GC) is a world health burden, ranging as the second cause of cancer death worldwide. Etiologically, GC arises not only from the combined effects of environmental factors and susceptible genetic variants but also from the accumulation of genetic and epigenetic alterations. In the last years, molecular oncobiology studies brought to light a number of genes that are implicated in gastric carcinogenesis. This review is intended to focus on the recently described basic aspects that play key roles in the process of gastric carcinogenesis. Genetic variants of the genes IL-10, IL-17, MUC1, MUC6, DNMT3B, SMAD4, and SERPINE1 have been reported to modify the risk of developing GC. Several genes have been newly associated with gastric carcinogenesis, both through oncogenic activation (GSK3ß, CD133, DSC2, P-Cadherin, CDH17, CD168, CD44, metalloproteinases MMP7 and MMP11, and a subset of miRNAs) and through tumor suppressor gene inactivation mechanisms (TFF1, PDX1, BCL2L10, XRCC, psiTPTE-HERV, HAI-2, GRIK2, and RUNX3). It also addressed the role of the inflammatory mediator cyclooxygenase-2 (COX-2) in the process of gastric carcinogenesis and its importance as a potential molecular target for therapy.


Assuntos
Infecções por Helicobacter/genética , Helicobacter pylori/fisiologia , Processos Neoplásicos , Neoplasias Gástricas/genética , Animais , Regulação Neoplásica da Expressão Gênica , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/isolamento & purificação , Humanos , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia
17.
Rev Port Cardiol (Engl Ed) ; 40(9): 641-648, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34503701

RESUMO

INTRODUCTION: Since 2011, the European guidelines have included a specific low-density lipoprotein cholesterol (LDL-C) target, <70 mg/dl, for very high cardiovascular risk (CVR) patients. However, registries have shown unsatisfactory results in obtaining this level of adequate lipid control. OBJECTIVES: To assess temporal trends in the use of lipid-lowering therapy (LLT) and attainment of adequate control in very high CVR patients since 2011. METHODS: We performed a retrospective observational study including very high CVR patients admitted in two periods: the first two years since the 2011 guidelines (2011/2012) and five years later (2016/2017). Lipid values, LLT, clinical variables and adequate lipid control rates were analyzed. RESULTS: A total of 1314 patients were reviewed (2011/2012: 638; 2016/2017: 676). Overall, 443 patients (33.7%) were not under LLT and only a slight improvement in drug prescription was observed from 2011/2012 to 2016/2017. In LLT users, the proportion of high-intensity LLT increased significantly in the later years (6.4% vs. 24.0%; p<0.001), but this was not associated with adequate lipid control. Overall, mean LDL-C was 95.4±37.2 mg/dl and adequate control was achieved in 320 patients (24.4%), without significant differences between 2011/2012 and 2016/2017 (p=0.282). Independent predictors of adequate control were male gender, older age, diabetes, chronic kidney disease, prior acute coronary syndrome, prior stroke and LLT, while stable coronary artery disease was associated with higher risk of failure. CONCLUSION: Even after the introduction of specific LDL-C targets, these are still not reached in most patients. Over a five-year period, LLT prescription only improved slightly, while adequate lipid control rates remained unchanged.


Assuntos
Doenças Cardiovasculares , Dislipidemias , Idoso , Biomarcadores , Doenças Cardiovasculares/epidemiologia , Dislipidemias/tratamento farmacológico , Fatores de Risco de Doenças Cardíacas , Humanos , Lipídeos , Masculino , Fatores de Risco , Resultado do Tratamento
18.
Lab Invest ; 90(8): 1132-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20386538

RESUMO

Transcription factors from the CCAAT/enhancer-binding protein (C/EBP) family are fundamental for the control of differentiation and proliferation of many adult tissues. C/EBP alpha has a crucial role in inducing terminal differentiation and is an established tumor suppressor gene in several cancer models. The objective of this study was to analyze the putative role of C/EBP alpha in gastric carcinoma (GC). We analyzed the expression of C/EBP alpha in normal and neoplastic gastric tissues, and assessed the role of C/EBP alpha on proliferation and differentiation of GC cells. In normal gastric mucosa, C/EBP alpha is expressed in the foveolar epithelium and co-localizes with the gastric differentiation marker trefoil factor 1 (TFF1). The expression of C/EBP alpha was found to be lost in 30% of GC cases. To evaluate the role of C/EBP alpha in cell proliferation and differentiation, we transfected GC cells with a full-length C/EBP alpha protein. We observed a significant decrease in proliferation in C/EBP alpha-transfected cells. This was accompanied by a decrease in Cyclin D1, an increase in P27 expression, and an increased expression of TFF1. Finally, we showed that inhibition of the Ras/MAPK pathway leads to increased C/EBP alpha and TFF1 expression, and decreased cell proliferation and cyclin D1 expression in GC cells. Our results suggest that C/EBP alpha (together with other members of the C/EBP family) has an active role in the control of differentiation and proliferation in normal gastric mucosa. In GC, loss of C/EBP alpha may be associated with the switch from a cellular differentiation to a cellular proliferation program, presumably as a consequence of Ras/MAPK pathway activation.


Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Mucosa Gástrica/metabolismo , Adulto , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Proteína alfa Estimuladora de Ligação a CCAAT/fisiologia , Proteínas Estimuladoras de Ligação a CCAAT/genética , Carcinoma/genética , Carcinoma/patologia , Diferenciação Celular/genética , Proliferação de Células , Transformação Celular Neoplásica/genética , Feminino , Mucosa Gástrica/patologia , Homeostase/genética , Humanos , Masculino , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção , Fator Trefoil-1 , Proteínas Supressoras de Tumor
19.
Helicobacter ; 15 Suppl 1: 34-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21054651

RESUMO

Gastric cancer (GC) is an important cause of morbidity and mortality worldwide. In addition to environmental factors, genetic factors also play an important role in GC etiology, as demonstrated by the fact that only a small proportion of individuals exposed to the known environmental risk factors develop GC. Molecular studies have provided evidence that GC arises not only from the combined effects of environmental factors and susceptible genetic variants but also from the accumulation of genetic and epigenetic alterations that play crucial roles in the process of cellular immortalization and tumorigenesis. This review is intended to focus on the recently described basic aspects that play key roles in the process of gastric carcinogenesis. Genetic variation in the genes DNMT3A, PSCA, VEGF, and XRCC1 has been reported to modify the risk of developing gastric carcinoma. Several genes have been newly associated with gastric carcinogenesis, both through oncogenic activation (MYC, SEMA5A, BCL2L12, RBP2 and BUBR1) and tumor suppressor gene inactivation mechanisms (KLF6, RELN, PTCH1A, CLDN11, and SFRP5). At the level of gastric carcinoma treatment, the HER-2 tyrosine kinase receptor has been demonstrated to be a molecular target of therapy.


Assuntos
Carcinoma/genética , Epigênese Genética , Polimorfismo Genético , Neoplasias Gástricas/genética , Predisposição Genética para Doença , Infecções por Helicobacter/complicações , Humanos , Proteína Reelina
20.
Cancer Immunol Res ; 8(11): 1407-1425, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32933968

RESUMO

Tumor growth is accompanied with dramatic changes in the cellular glycome, such as the aberrant expression of complex branched N-glycans. However, the role of this protumoral N-glycan in immune evasion and whether its removal contributes to enhancement of immune recognition and to unleashing an antitumor immune response remain elusive. We demonstrated that branched N-glycans are used by colorectal cancer cells to escape immune recognition, instructing the creation of immunosuppressive networks through inhibition of IFNγ. The removal of this "glycan-mask" exposed immunogenic mannose glycans that potentiated immune recognition by DC-SIGN-expressing immune cells, resulting in an effective antitumor immune response. We revealed a glycoimmune checkpoint in colorectal cancer, highlighting the therapeutic efficacy of its deglycosylation to potentiate immune recognition and, thus, improving cancer immunotherapy.


Assuntos
Neoplasias Colorretais/imunologia , Imunoterapia/métodos , Polissacarídeos/metabolismo , Progressão da Doença , Humanos
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