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1.
Pediatr Res ; 95(2): 566-572, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38057577

RESUMO

BACKGROUND: Studies examining the association between in utero Zika virus (ZIKV) exposure and child neurodevelopmental outcomes have produced varied results. METHODS: We aimed to assess neurodevelopmental outcomes among normocephalic children born from pregnant people enrolled in the Zika in Pregnancy in Honduras (ZIPH) cohort study, July-December 2016. Enrollment occurred during the first prenatal visit. Exposure was defined as prenatal ZIKV IgM and/or ZIKV RNA result at enrollment. Normocephalic children, >6 months old, were selected for longitudinal follow-up using the Bayley Scales of Infant and Toddler Development (BSID-III) and the Ages & Stages Questionnaires: Social-Emotional (ASQ:SE-2). RESULTS: One hundred fifty-two children were assessed; after exclusion, 60 were exposed and 72 were unexposed to ZIKV during pregnancy. Twenty children in the exposed group and 21 children in the unexposed group had a composite score <85 in any of the BSID-III domains. Although exposed children had lower cognitive and language scores, differences were not statistically significant. For ASQ:SE-2 assessment, there were not statistically significant differences between groups. CONCLUSIONS: This study found no statistically significant differences in the neurodevelopment of normocephalic children between in utero ZIKV exposed and unexposed. Nevertheless, long-term monitoring of children with in utero ZIKV exposure is warranted. IMPACT: This study found no statistically significant differences in the neurodevelopment in normocephalic children with in utero Zika virus exposure compared to unexposed children, although the exposed group showed lower cognitive and language scores that persisted after adjustment by maternal age and education and after excluding children born preterm and low birth weight from the analysis. Children with prenatal Zika virus exposure, including those normocephalic and have no evidence of abnormalities at birth, should be monitored for neurodevelopmental delays. Follow-up is important to be able to detect developmental abnormalities that might not be detected earlier in life.


Assuntos
Craniossinostoses , Complicações Infecciosas na Gravidez , Efeitos Tardios da Exposição Pré-Natal , Infecção por Zika virus , Zika virus , Gravidez , Lactente , Recém-Nascido , Feminino , Humanos , Estudos de Coortes , Infecção por Zika virus/diagnóstico , Desenvolvimento Infantil
2.
BMC Genomics ; 23(1): 465, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35751020

RESUMO

BACKGROUND: Type 2 diabetes mellitus (T2DM) has been associated with treatment failure, and the development of drug resistance in tuberculosis (TB). Also, whole-genome sequencing has provided a better understanding and allowed the growth of knowledge about polymorphisms in genes associated with drug resistance. Considering the above, this study analyzes genome sequences to evaluate the influence of type 2 diabetes mellitus in the development of mutations related to tuberculosis drug resistance. M. tuberculosis isolates from individuals with (n = 74), and without (n = 74) type 2 diabetes mellitus was recovered from online repositories, and further analyzed. RESULTS: The results showed the presence of 431 SNPs with similar proportions between diabetics, and non-diabetics individuals (48% vs. 52%), but with no significant relationship. A greater number of mutations associated with rifampicin resistance was observed in the T2DM-TB individuals (23.2% vs. 16%), and the exclusive presence of rpoBQ432L, rpoBQ432P, rpoBS441L, and rpoBH445L variants. While these variants are not private to T2DM-TB cases they are globally rare highlighting a potential role of T2DM. The phylogenetic analysis showed 12 sublineages, being 4.1.1.3, and 4.1.2.1 the most prevalent in T2DM-TB individuals but not differing from those most prevalent in their geographic location. Four clonal complexes were found, however, no significant relationship with T2DM was observed. Samples size and potential sampling biases prevented us to look for significant associations. CONCLUSIONS: The occurrence of globally rare rifampicin variants identified only in isolates from individuals with T2DM could be due to the hyperglycemic environment within the host. Therefore, further studies about the dynamics of SNPs' generation associated with antibiotic resistance in patients with diabetes mellitus are necessary.


Assuntos
Diabetes Mellitus Tipo 2 , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Testes de Sensibilidade Microbiana , Filogenia , Polimorfismo de Nucleotídeo Único , Rifampina/uso terapêutico , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Tuberculose/genética , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/genética , Sequenciamento Completo do Genoma
3.
Sensors (Basel) ; 22(15)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35957403

RESUMO

The Industrial Internet of Things (IIoT) is bringing evolution with remote monitoring, intelligent analytics, and control of industrial processes. However, as the industrial world is currently in its initial stage of adopting full-stack development solutions with IIoT, there is a need to address the arising challenges. In this regard, researchers have proposed IIoT architectures based on different architectural layers and emerging technologies for the end-to-end integration of IIoT systems. In this paper, we review and compare three widely accepted IIoT reference architectures and present a state-of-the-art review of conceptual and experimental IIoT architectures from the literature. We identified scalability, interoperability, security, privacy, reliability, and low latency as the main IIoT architectural requirements and detailed how the current architectures address these challenges by using emerging technologies such as edge/fog computing, blockchain, SDN, 5G, Machine Learning, and Wireless Sensor Networks (WSN). Finally, we discuss the relation between the current challenges and emergent technologies and present some opportunities and directions for future research work.


Assuntos
Blockchain , Internet das Coisas , Segurança Computacional , Privacidade , Reprodutibilidade dos Testes
4.
Molecules ; 27(3)2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35164296

RESUMO

The transient vanilloid receptor potential type 1 (TRPV1) regulates neuronal and vascular functions mediated by nitric oxide (NO) and by the calcitonin gene-related peptide (CGRP). Here, we study the participation of TRPV1 in the regulation of myocardial injury caused by ischemia-reperfusion and in the control of NO, tetrahydrobiopterin (BH4), the cGMP pathway, CGRP, total antioxidant capacity (TAC), malondialdehyde (MDA) and phosphodiesterase-3 (PDE-3). Isolated hearts of Wistar rats perfused according to the Langendorff technique were used to study the effects of an agonist of TRPV1, capsaicin (CS), an antagonist, capsazepine (CZ), and their combination CZ+CS. The hearts were subjected to three conditions: (1) control, (2) ischemia and (3) ischemia-reperfusion. We determined cardiac mechanical activity and the levels of NO, cGMP, BH4, CGRP, TAC, MDA and PDE-3 in ventricular tissue after administration of CS, CZ and CZ+CS. Western blots were used to study the expressions of eNOS, iNOS and phosphorylated NOS (pNOS). Structural changes were determined by histological evaluation. CS prevented damage caused by ischemia-reperfusion by improving cardiac mechanical activity and elevating the levels of NO, cGMP, BH4, TAC and CGRP. TRPV1 and iNOS expression were increased under ischemic conditions, while eNOS and pNOS were not modified. We conclude that the activation of TRPV1 constitutes a therapeutic possibility to counteract the damage caused by ischemia and reperfusion by regulating the NO pathway through CGRP.


Assuntos
Coração/fisiopatologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Óxido Nítrico/metabolismo , Estresse Oxidativo , Canais de Cátion TRPV/metabolismo , Animais , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais
5.
Prev Med ; 153: 106801, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34508733

RESUMO

WHO cervical cancer elimination goals comprise 70% of highly-sensitive screening coverage and 90% treatment of precancerous lesions. Triage for HPV-positive women may challenge sensitivity of screening algorithms and women's follow-up, particularly in low- and middle-income countries (LMIC) where screening quality and protocol adherence are frequently deficient. We aimed to determine the accuracy of triage for HPV positive women in routine screening services from Colombia by a prospective cross-sectional study. Consecutively, HPV DNA-positive women underwent six triage strategies (conventional cytology, two methods of visual inspection, HPV16/18/45-genotyping, telomerase, and HPV mRNA). Positive triage results underwent regular colposcopy/biopsy in public hospitals. Adjusted sensitivity, specificity, and predictive values for CIN2+/CIN3+ were estimated for stand-alone and combined tests. We explored the impact of triage strategies on referral rates and the complete screening algorithm (screening plus triage). Overall 16,242 women underwent HPV screening and 1789 (11.0%) were HPV-positive. In total, 20.1% of women were lost to follow-up. mRNA showed the highest positivity rate (0.64 among HPV-positive and 0.05 among the total screened cohort), the highest sensitivity (0.94 95%CI 0.75-0.96), and the lowest specificity (0.36 95%CI 0.29-0.43). Parallel testing with HPV-mRNA revealed the highest increase in sensitivity for all triage strategies. Accuracy of cytology and visual inspection differ between screening units but parallel testing with HPV16/18/45 genotyping significantly increased their sensitivity (over 0.80). Morphology-based triage for HPV-positive women remains a suitable alternative for routine practice in LMIC if combined with HPV16/18/45-genotyping; however, point-of-care triage would be preferable to reduce losses to follow-up. HPV-mRNA triage deserves cost-benefit analyses.


Assuntos
Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Colômbia , Colposcopia , Estudos Transversais , Detecção Precoce de Câncer/métodos , Feminino , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Programas de Rastreamento/métodos , Infecções por Papillomavirus/patologia , Gravidez , Estudos Prospectivos , Triagem , Esfregaço Vaginal/métodos , Displasia do Colo do Útero/patologia
6.
Sensors (Basel) ; 21(6)2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33803889

RESUMO

With the significant advancement of sensor and communication technology and the reliable application of obstacle detection techniques and algorithms, automated driving is becoming a pivotal technology that can revolutionize the future of transportation and mobility. Sensors are fundamental to the perception of vehicle surroundings in an automated driving system, and the use and performance of multiple integrated sensors can directly determine the safety and feasibility of automated driving vehicles. Sensor calibration is the foundation block of any autonomous system and its constituent sensors and must be performed correctly before sensor fusion and obstacle detection processes may be implemented. This paper evaluates the capabilities and the technical performance of sensors which are commonly employed in autonomous vehicles, primarily focusing on a large selection of vision cameras, LiDAR sensors, and radar sensors and the various conditions in which such sensors may operate in practice. We present an overview of the three primary categories of sensor calibration and review existing open-source calibration packages for multi-sensor calibration and their compatibility with numerous commercial sensors. We also summarize the three main approaches to sensor fusion and review current state-of-the-art multi-sensor fusion techniques and algorithms for object detection in autonomous driving applications. The current paper, therefore, provides an end-to-end review of the hardware and software methods required for sensor fusion object detection. We conclude by highlighting some of the challenges in the sensor fusion field and propose possible future research directions for automated driving systems.

7.
Eur Respir J ; 56(1)2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32241831

RESUMO

BACKGROUND: In animal models of pulmonary arterial hypertension (PAH), angiotensin-converting enzyme (ACE)2 and angiotensin (Ang)-(1-7) have been shown to have vasodilatory, antiproliferative, antifibrotic and antihypertrophic properties. However, the status and role of the ACE2-Ang(1-7) axis in human PAH is incompletely understood. METHODS: We studied 85 patients with a diagnosis of PAH of distinct aetiologies. 55 healthy blood donors paired for age and sex served as controls. Blood samples were obtained from the pulmonary artery in patients with PAH during right heart catheterisation. Peripheral blood was obtained for both groups. Ang(1-7) and -II were measured using zone capillary electrophoresis. Aldosterone, Ang(1-9), AngA and ACE2 were measured using ELISA, and ACE2 activity was determined enzymatically. RESULTS: Of the 85 patients, 47 had idiopathic PAH, 25 had PAH associated with congenital heart disease and 13 had PAH associated with collagen vascular disease. Compared to controls, patients with PAH had a higher concentration of AngII (median 1.03, interquartile range 0.72-1.88 pmol·mL-1 versus 0.19, 0.10-0.37 pmol·mL-1; p<0.001) and of aldosterone (88.7, 58.7-132 ng·dL-1 versus 12.9, 9.55-19.9 ng·dL-1; p<0.001). Conversely, PAH patients had a lower concentration of Ang(1-7) than controls (0.69, 0.474-0.91 pmol·mL-1 versus 4.07, 2.82-6.73 pmol·mL-1; p<0.001), and a lower concentration of Ang(1-9) and AngA. Similarly, the ACE2 concentration was higher than in controls (8.7, 5.35-13.2 ng·mL-1 versus 4.53, 1.47-14.3 ng·mL-1; p=0.011), whereas the ACE2 activity was significantly reduced (1.88, 1.08-2.81 nmol·mL-1 versus 5.97, 3.1-17.8 nmol·mL-1; p<0.001). No significant differences were found among the three different aetiological forms of PAH. CONCLUSIONS: The AngII-ACE2-Ang(1-7) axis appears to be altered in human PAH and we propose that this imbalance, in favour of AngII, plays a role in the pathogenesis of the severe PAH. Further mechanistic studies are warranted.


Assuntos
Enzima de Conversão de Angiotensina 2 , Hipertensão Arterial Pulmonar , Angiotensina I , Animais , Humanos , Fragmentos de Peptídeos , Peptidil Dipeptidase A
8.
Nature ; 498(7452): 94-8, 2013 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-23665961

RESUMO

It has been argued that the evolution of plant genome size is principally unidirectional and increasing owing to the varied action of whole-genome duplications (WGDs) and mobile element proliferation. However, extreme genome size reductions have been reported in the angiosperm family tree. Here we report the sequence of the 82-megabase genome of the carnivorous bladderwort plant Utricularia gibba. Despite its tiny size, the U. gibba genome accommodates a typical number of genes for a plant, with the main difference from other plant genomes arising from a drastic reduction in non-genic DNA. Unexpectedly, we identified at least three rounds of WGD in U. gibba since common ancestry with tomato (Solanum) and grape (Vitis). The compressed architecture of the U. gibba genome indicates that a small fraction of intergenic DNA, with few or no active retrotransposons, is sufficient to regulate and integrate all the processes required for the development and reproduction of a complex organism.


Assuntos
Evolução Molecular , Genoma de Planta/genética , Magnoliopsida/genética , DNA Intergênico/genética , Duplicação Gênica/genética , Genes de Plantas/genética , Modelos Genéticos , Solanum/genética , Sintenia/genética , Vitis/genética
9.
Molecules ; 24(2)2019 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-30642049

RESUMO

Myocardial infarction (MI) initiates an inflammatory response that promotes both beneficial and deleterious effects. The early response helps the myocardium to remove damaged tissue; however, a prolonged later response brings cardiac remodeling characterized by functional, metabolic, and structural pathological changes. Current pharmacological treatments have failed to reverse ischemic-induced cardiac damage. Therefore, our aim was to study if clofibrate treatment was capable of decreasing inflammation and apoptosis, and reverse ventricular remodeling and MI-induced functional damage. Male Wistar rats were assigned to (1) Sham coronary artery ligation (Sham) or (2) Coronary artery ligation (MI). Seven days post-MI, animals were further divided to receive vehicle (V) or clofibrate (100 mg/kg, C) for 7 days. The expression of IL-6, TNF-α, and inflammatory related molecules ICAM-1, VCAM-1, MMP-2 and -9, nuclear NF-kB, and iNOS, were elevated in MI-V. These inflammatory biomarkers decreased in MI-C. Also, apoptotic proteins (Bax and pBad) were elevated in MI-V, while clofibrate augmented anti-apoptotic proteins (Bcl-2 and 14-3-3ε). Clofibrate also protected MI-induced changes in ultra-structure. The ex vivo evaluation of myocardial functioning showed that left ventricular pressure and mechanical work decreased in infarcted rats; clofibrate treatment raised those parameters to control values. Echocardiogram showed that clofibrate partially reduced LV dilation. In conclusion, clofibrate decreases cardiac remodeling, decreases inflammatory molecules, and partly preserves myocardial diameters.


Assuntos
Clofibrato/farmacologia , Hipolipemiantes/farmacologia , Inflamação/patologia , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/patologia , Remodelação Ventricular/efeitos dos fármacos , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Infarto do Miocárdio/metabolismo , PPAR alfa/metabolismo , Roedores
10.
Microbiology (Reading) ; 164(4): 685-696, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29485393

RESUMO

Verticillium dahliae is a soilborne fungus that causes vascular wilt diseases on numerous plant species worldwide. The production of darkly melanized microsclerotia is crucial in the disease cycle of V. dahliae, as these structures allow for long-term survival in soil. Previously, transcriptomic and genomic analysis identified a cluster of genes in V. dahliae that encodes some dihydroxynaphthalene (DHN) melanin biosynthetic pathway homologues found in related fungi. In this study, we explored the roles of cluster-specific transcription factor VdCmr1, as well as two other genes within the cluster encoding a polyketide synthase (VdPKS1) and a laccase (VdLac1), enzymes at initial and endpoint steps in DHN melanin production. The results revealed that VdCmr1 and VdPKS1 are required for melanin production, but neither is required for microsclerotia production. None of the three genes were required for pathogenesis on tobacco and lettuce. Exposure of ΔVdCmr1 and wild-type strains to UV irradiation, or to high temperature (40 °C), revealed an approx. 50 % reduction of survival in the ΔVdCmr1 strain, relative to the wild-type strain, in response to either condition. Expression profiles revealed that expression of some melanin biosynthetic genes are in part dependent on VdCmr1. Combined data indicate VdCmr1 is a key regulator of melanin biosynthesis, and that via regulation of melanogenesis, VdCmr1 affects survival of V. dahliae in response to abiotic threats. We conclude with a model showing regulation of VdCmr1 by a high osmolarity glycerol response (Hog)-type MAP kinase pathway.


Assuntos
Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Melaninas/biossíntese , Fatores de Transcrição/metabolismo , Verticillium/genética , Proteínas Fúngicas/genética , Deleção de Genes , Lacase/genética , Modelos Biológicos , Naftóis , Doenças das Plantas/microbiologia , Policetídeo Sintases/genética , Temperatura , Fatores de Transcrição/genética , Raios Ultravioleta , Verticillium/metabolismo , Verticillium/efeitos da radiação
11.
Int J Mol Sci ; 18(11)2017 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-29135932

RESUMO

Numerous studies have supported a role for oxidative stress in the development of ischemic damage and endothelial dysfunction. Crataegus oxyacantha (Co) and Rosmarinus officinalis (Ro) extracts are polyphenolic-rich compounds that have proven to be efficient in the treatment of cardiovascular diseases. We studied the effect of extracts from Co and Ro on the myocardial damage associated with the oxidative status and to the production of different vasoactive agents. Rats were assigned to the following groups: (a) sham; (b) vehicle-treated myocardial infarction (MI) (MI-V); (c) Ro extract-treated myocardial infarction (MI-Ro); (d) Co extract-treated myocardial infarction (MI-Co); or (e) Ro+Co-treated myocardial infarction (MI-Ro+Co). Ro and Co treatments increased total antioxidant capacity, the expression of superoxide dismutase (SOD)-Cu2+/Zn2+, SOD-Mn2+, and catalase, with the subsequent decline of malondialdehyde and 8-hydroxy-2'-deoxyguanosine levels. The extracts diminished vasoconstrictor peptide levels (angiotensin II and endothelin-1), increased vasodilators agents (angiotensin 1-7 and bradikinin) and improved nitric oxide metabolism. Polyphenol treatment restored the left intraventricular pressure and cardiac mechanical work. We conclude that Ro and Co treatment attenuate morphological and functional ischemic-related changes by both an oxidant load reduction and improvement of the balance between vasoconstrictors and vasodilators.


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Crataegus/química , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/patologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Rosmarinus/química , Angiotensinas/farmacologia , Animais , Biomarcadores/metabolismo , Bradicinina/farmacologia , Fármacos Cardiovasculares/farmacologia , Cromatografia Líquida de Alta Pressão , Testes de Função Cardíaca , Hemodinâmica/efeitos dos fármacos , Masculino , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Miocárdio/ultraestrutura , Óxido Nítrico Sintase Tipo III/metabolismo , Extratos Vegetais/farmacologia , Folhas de Planta/química , Ratos Wistar , Vasoconstrição/efeitos dos fármacos
12.
Can J Physiol Pharmacol ; 94(6): 634-42, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27050838

RESUMO

Myocardial infarction (MI) has been associated with an inflammatory response and a rise in TNF-α, interleukin (IL)-1ß, and IL-6. Peroxisome proliferator-activated receptors (PPARs) promote a decreased expression of inflammatory molecules. We aimed to study whether PPAR stimulation by clofibrate decreases inflammation and reduces infarct size in rats with MI. Male Wistar rats were randomized into 3 groups: control, MI + vehicle, and MI + clofibrate (100 mg/kg). Treatment was administered for 3 consecutive days, previous to 2 h of MI. MI induced an increase in protein expression, mRNA content, and enzymatic activity of inducible nitric oxide synthase (iNOS). Additionally, MI incited an increased expression of matrix metalloproteinase (MMP)-2 and MMP-9, intercellular adhesion molecule (ICAM)-1, and IL-6. MI also elevated the nuclear content of nuclear factor-κB (NF-κB) and decreased IκB, both in myocyte nuclei and cytosol. Clofibrate treatment prevented MI-induced changes in iNOS, MMP-2 and MMP-9, ICAM-1, IL-6, NF-κB, and IκB. Infarct size was smaller in clofibrate-treated rats compared to MI-vehicle animals. In silico analysis exhibited 3 motifs shared by genes from renin-angiotensin system, PPARα, iNOS, MMP-2 and MMP-9, ICAM-1, and VCAM-1, suggesting a cross regulation. In conclusion, PPARα-stimulation prevents overexpression of pro-inflammatory molecules and preserves viability in an experimental model of acute MI.


Assuntos
Modelos Animais de Doenças , Regulação para Baixo/fisiologia , Mediadores da Inflamação/metabolismo , Infarto do Miocárdio/metabolismo , PPAR alfa/biossíntese , Animais , Clofibrato/farmacologia , Clofibrato/uso terapêutico , Regulação da Expressão Gênica , Masculino , Infarto do Miocárdio/tratamento farmacológico , PPAR alfa/genética , Distribuição Aleatória , Ratos , Ratos Wistar
13.
J Cardiovasc Pharmacol ; 65(5): 430-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25658458

RESUMO

We have recently demonstrated that peroxisome proliferator-activated receptor alpha (PPARα) stimulation lowers the production of angiotensin II while increasing the production of Ang-(1-7), both in cardiac and plasmatic level. This stimulation improves nitric oxide bioavailability, preserving cardiac histologic features and functioning. Based on these results, we decided to study the effect of PPARα stimulation on renin-angiotensin system components of ischemic myocardium. Male Wistar rats (weighing 300-350 g) were assigned to the following groups: (1) sham, (2) myocardial ischemia vehicle-treated (MI-V), and (3) myocardial ischemia clofibrate-treated. Expression of the angiotensin-converting enzyme increased during ischemia, whereas clofibrate-treated group remained comparable to control. Activation of the PPARα receptor stimulated the expression of angiotensin-converting enzyme-2; while the activity of this enzyme was increased in MI-V, clofibrate inhibited any change. The concentration of bradykinin and phospho-Akt(SER473) in homogenate increased in the animals treated with the drug. Mas receptor expression increased in MI-V rats. In conclusion, stimulation of PPARα by clofibrate prevents an increase in the activity of renin-angiotensin system and promotes the production of vasodilator substances.


Assuntos
Clofibrato/farmacologia , Isquemia Miocárdica/tratamento farmacológico , Miocárdio/metabolismo , PPAR alfa/agonistas , Sistema Renina-Angiotensina/efeitos dos fármacos , Enzima de Conversão de Angiotensina 2 , Animais , Bradicinina/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , Masculino , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatologia , PPAR alfa/metabolismo , Peptidil Dipeptidase A/metabolismo , Fosforilação , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Wistar , Receptores Acoplados a Proteínas G/metabolismo , Serina , Transdução de Sinais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
14.
Can J Physiol Pharmacol ; 93(4): 299-308, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25761067

RESUMO

We investigated the involvement of cyclooxygenase-2 (COX-2) and the renin-angiotensin system in N(G)-nitro-L-arginine methyl ester (L-NAME)-induced hypertension. Male Wistar rats were treated with L-NAME (75.0 mg·(kg body mass)(-1)·day(-1), in their drinking water) for different durations (1-33 days). COX-2 and renin mRNA were measured using real-time PCR in the renal cortex, and prostanoids were assessed in the renal perfusate, whereas angiotensin II (Ang II) and Ang (1-7) were quantified in plasma. In some rats, nitric oxide synthase inhibition was carried out in conjunction with oral administration of captopril (30.0 mg·kg(-1)·day(-1)) or celecoxib (1.0 mg·kg(-1)·day(-1)) for 2 or 19 days. We found a parallel increase in renocortical COX-2 and renin mRNA starting at day 2 of treatment with L-NAME, and both peaked at 19-25 days. In addition, L-NAME increased renal 6-Keto-PGF(1α) (prostacyclin (PGI2) metabolite) and plasma Ang II from day 2, but reduced plasma Ang (1-7) at day 19. Captopril prevented the increase in blood pressure, which was associated with lower plasma Ang II and increased COX-2-derived 6-Keto-PGF(1α) at day 2 and plasma Ang (1-7) at day 19. Celecoxib partially prevented the increase in blood pressure; this effect was associated with a reduction in plasma Ang II. These findings indicate that renal COX-2 expression increased in parallel with renin expression, renal PGI2 synthesis, and plasma Ang II in L-NAME-induced hypertension.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hipertensão Renal/metabolismo , Córtex Renal/metabolismo , Renina/metabolismo , 6-Cetoprostaglandina F1 alfa/sangue , 6-Cetoprostaglandina F1 alfa/metabolismo , Angiotensina I/sangue , Angiotensina I/metabolismo , Angiotensina II/sangue , Angiotensina II/metabolismo , Animais , Anti-Hipertensivos/uso terapêutico , Captopril/uso terapêutico , Celecoxib/uso terapêutico , Ciclo-Oxigenase 2/química , Ciclo-Oxigenase 2/genética , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Hipertensão Renal/sangue , Hipertensão Renal/prevenção & controle , Córtex Renal/efeitos dos fármacos , Córtex Renal/enzimologia , Masculino , NG-Nitroarginina Metil Éster , Óxido Nítrico/metabolismo , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/metabolismo , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos Wistar , Renina/genética
15.
Gac Med Mex ; 151(5): 660-5, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-26526481

RESUMO

Since the end of the XVIII century, digitalis glycosides were employed in heart failure. They were considered initially as diuretics and later as cardiotonic agents or as positive inotropics. At the present time there are varied groups of positive inotropic agents, which have a beneficial action on the failing human myocardium. For example, the beta adrenergics, the phosphodiesterase III inhibitors such as milrinone, or the sensibilizers of myocardial proteins to Ca++ such as levosimendan and omecamtiv mecarbil. However, following the opinion of distinguished cardiologists, in the case of heart failure associated to atrial fibrillation, digitalis cannot be substituted.


Assuntos
Glicosídeos Digitálicos/história , Digitalis , Farmacologia/história , História do Século XVI , História do Século XVIII , História do Século XIX , Humanos , México
16.
bioRxiv ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38559128

RESUMO

Normal aging is associated with significant deleterious cerebrovascular changes; these have been implicated in disease pathogenesis and increased susceptibility to ischemic injury. While these changes are well documented in the brain, few studies have been conducted in the spinal cord. Here, we utilize specialized contrast-enhanced ultrasound (CEUS) imaging to investigate age-related changes in cervical spinal vascular anatomy and hemodynamics in male Fisher 344 rats, a common strain in aging research. Aged rats (24-26 mo., N=6) exhibited significant tortuosity in the anterior spinal artery and elevated vascular resistance compared to adults (4-6 mo., N=6; tortuosity index 2.20±0.15 vs 4.74±0.45, p<0.05). Baseline blood volume was lower in both larger vessels and the microcirculation in the aged cohort, specifically in white matter (4.44e14±1.37e13 vs 3.66e14±2.64e13 CEUS bolus AUC, p<0.05). To elucidate functional differences, animals were exposed to a hypoxia challenge; whereas adult rats exhibited significant functional hyperemia in both gray and white matter (GM: 1.13±0.10-fold change from normoxia, p<0.05; WM: 1.16±0.13, p<0.05), aged rats showed no response. Immunohistochemistry revealed reduced pericyte coverage and activated microglia behavior in aged rats, which may partially explain the lack of vascular response. This study provides the first in vivo description of age-related hemodynamic differences in the cervical spinal cord.

17.
Microorganisms ; 12(2)2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38399727

RESUMO

Genetic variation in tuberculosis is influenced by the host environment, patients with comorbidity, and tuberculosis-type 2 diabetes mellitus (TB-T2DM) and implies a higher risk of treatment failure and development of drug resistance. Considering the above, this study aimed to evaluate the influence of T2DM on the dynamic of polymorphisms related to antibiotic resistance in TB. Fifty individuals with TB-T2DM and TB were initially characterized, and serial isolates of 29 of these individuals were recovered on day 0 (diagnosis), 30, and 60. Genomes were sequenced, variants related to phylogeny and drug resistance analyzed, and mutation rates calculated and compared between groups. Lineage X was predominant. At day 0 (collection), almost all isolates from the TB group were sensitive, apart from four isolates from the TB-T2DM group showing the mutation katG S315T, from which one isolate had the mutations rpoB S450L, gyrA A90G, and gyrA D94G. This pattern was observed in a second isolate at day 30. The results provide a first overview of the dynamics of mutations in resistance genes from individuals with TB-T2DM, describing an early development of resistance to isoniazid and a rapid evolution of resistance to other drugs. Although preliminary, these results help to explain the increased risk of drug resistance in individuals with TB and T2DM.

18.
Front Microbiol ; 15: 1376669, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650875

RESUMO

Introduction: The emergence of multi-drug-resistant bacteria is one of the main concerns in the health sector worldwide. The conventional strategies for treatment and prophylaxis against microbial infections include the use of antibiotics. However, these drugs are failing due to the increasing antimicrobial resistance. The unavailability of effective antibiotics highlights the need to discover effective alternatives to combat bacterial infections. One option is the use of metallic nanoparticles, which are toxic to some microorganisms due to their nanometric size. Methods: In this study we (1) synthesize and characterize bismuth and silver nanoparticles, (2) evaluate the antibacterial activity of NPs against Staphylococcus aureus and Escherichia coli in several infection models (in vivo models: infected wound and sepsis and in vitro model: mastitis), and we (3) determine the cytotoxic effect on several cell lines representative of the skin tissue. Results and discussion: We obtained bimetallic nanoparticles of bismuth and silver in a stable aqueous solution from a single reaction by chemical synthesis. These nanoparticles show antibacterial activity on S. aureus and E. coli in vitro without cytotoxic effects on fibroblast, endothelial vascular, and mammary epithelium cell lines. In an infected-wound mice model, antibacterial effect was observed, without effect on in vitro mastitis and sepsis models.

20.
PeerJ ; 11: e14981, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36968001

RESUMO

Background: Emulsions have been widely used as immunological adjuvants. But the use of materials derived from plants such as cottonseed oil, alpha-tocopherol, or minerals such as zinc, as well as their use at the nanometric scale has been little explored. In this study, we develop a new miniemulsion and evaluated its antioxidant and phagocytic capacity, as well as parameters related to immune response stimulation by cytokine expression and antibodies production in a mice model. Methods: Formulated CN (cottonseed oil miniemulsion) and CNZ (cottonseed oil miniemulsion whit zinc oxide nanoparticles) miniemulsions were characterized by scanning electronic microscopy SEM, DLS and FT-IR. In murine macrophages, splenocytes and thymocytes primary cultures safety and cytotoxicity were determined by MTT. In macrophages the antioxidant and phagocytic capacity was evaluated. In BALB/c mice, the stimulation of the immune system was determined by the expression of cytokines and the production of antibodies. Results: The CN and CNZ presented stability for 90 days. Immediately after preparation, the CN presented a higher particle size (543.1 nm) than CNZ (320 nm). FT-IR demonstrated the correct nanoparticle synthesis by the absence of sulfate groups. CN and CNZ (1.25 to 10 µL/mL) had no toxic effect on macrophages (p = 0.108), splenocytes (p = 0.413), and thymocytes (p = 0.923). All CN and CNZ doses tested induced nitric oxide and antioxidants production in dose dependent manner when compared with control. CN-ovalbumin and CNZ-ovalbumin treatments in femoral subcutaneous tissue area showed inflammation with higher leukocyte infiltration compared with FCA. The intraperitoneal administration with CN, CNZ, and FCA showed a higher total intraperitoneal cells recruitment (CD14+) after 24 h of inoculation than control (p = 0.0001). CN and CNZ increased the phagocyte capacity with respect to untreated macrophages in the Candida albicans-phagocytosis assay. The evaluation of residual CFU indicated that only CN significantly decreased (p = 0.004) this value at 3 h. By other side, only CN increased (p = 0.002) the nitric oxide production. CNZ stimulated a major INFγ secretion compared with FCA at day 7. A major IL-2 secretion was observed at days 7 and 14, stimulated with CN and CNZ. Both miniemulsions did not affect the antibody isotypes production (IgG1, IgG2a, IgG3, IgA and IgM) at days 7, 14, 28, and 42. CN induced a significant IgG production against OVA, but lesser than FCA. Conclusions: The two new miniemulsions with adjuvant and antioxidant capacity, were capable of generating leukocyte infiltration and increased cytokines and antibodies production.


Assuntos
Óxido de Zinco , Animais , Camundongos , Óxido de Zinco/farmacologia , alfa-Tocoferol/farmacologia , Óleo de Sementes de Algodão , Ovalbumina , Antioxidantes/farmacologia , Óxido Nítrico , Espectroscopia de Infravermelho com Transformada de Fourier , Adjuvantes Imunológicos/farmacologia , Citocinas , Imunoglobulina G , Adjuvantes Farmacêuticos
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