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1.
Appl Microbiol Biotechnol ; 106(4): 1475-1492, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35092453

RESUMO

The protease catalytic subunit of the nuclear inclusion protein A from tobacco etch virus (TEVp) is widely used to remove tags and fusion proteins from recombinant proteins. Some intrinsic drawbacks to its recombinant production have been studied for many years, such as low solubility, auto-proteolysis, and instability. Some point mutations have been incorporated in the amino acid protease sequence to improve its production. Here, a comprehensive review of each mutation reported so far has been made to incorporate them into a mutant called TEVp7M with a total of seven changes. This mutant with a His7tag at N-terminus was produced with remarkable purification yields (55 mg/L of culture) from the soluble fraction in a single step affinity purification. The stability of His7-TEVp7M was analyzed and compared with the single mutant TEVp S219V, making evident that His7-TEVp7M shows very constant thermal stability against pH variation, whereas TEVp S219V is highly sensitive to this change. The cleavage reaction was optimized by determining the amount of protease that could cleave a 100-fold excess substrate in the shortest possible time at 30 °C. Under these conditions, His7-TEVp7M was able to cleave His-tag in the buffers commonly used for affinity purification. Finally, a structural analysis of the mutations showed that four of them increased the polarity of the residues involved and, consequently, showed increased solubility of TEVp and fewer hydrophobic regions exposed to the solvent. Taken together, the seven changes studied in this work improved stability, solubility, and activity of TEVp producing enough protease to digest large amounts of tags or fusion proteins. KEY POINTS: • Production of excellent yields of a TEVp (TEVp7M) by incorporation of seven changes. • His-tag removal in an excess substrate in the common buffers used for purification. • Incorporated mutations improve polarity, stability, and activity of TEVp7M.


Assuntos
Endopeptidases , Cromatografia de Afinidade , Endopeptidases/genética , Endopeptidases/metabolismo , Proteólise , Proteínas Recombinantes de Fusão/metabolismo
2.
Int Urogynecol J ; 33(3): 741-744, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34623456

RESUMO

INTRODUCTION AND HYPOTHESIS: The mid-urethral sling (MUS) is considered the gold standard for stress urinary incontinence (SUI). Nevertheless, this procedure is not excluded from postsurgical complications, which can be challenging for most clinicians. Hence, one of the main concerns about this procedure is late postoperative voiding dysfunction (LDS), defined as obstructive symptoms 6 weeks after surgery. Primary medical management regularly includes expectant management and rehabilitation, including the mid-urethral cut sling (MUCS) as an alternative when it fails. This video provides an anatomical illustration and detailed description of the surgical steps of the J-cut of the lateral sling. MATERIALS AND METHODS: We set up a step-by-step surgical process and provided some advice for MUCS in a video; this material included how to position the sling, dissect, isolate the synthetic material, release adhesions and make a lateral cut of the MUS. Additionally, a case series of 30 patients from our institution is described to confirm the effectiveness of MUCS to manage delayed voiding dysfunction syndrome. RESULTS: MUCS in LDS was beneficial for our patients. Obstructive symptoms improved clinically from 75% to 100%, and urgency-related symptoms decreased from 57.9% to 26.3%, evidencing 20% SUI post-MUCS surgery. CONCLUSIONS: The lateral cut of the mid-urethral tape should be considered a surgical alternative for the resolution of post-sling late voiding dysfunction syndrome in patients who do not improve with expectant management.


Assuntos
Slings Suburetrais , Incontinência Urinária por Estresse , Humanos , Masculino , Período Pós-Operatório , Slings Suburetrais/efeitos adversos , Síndrome , Uretra , Incontinência Urinária por Estresse/etiologia , Incontinência Urinária por Estresse/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos
3.
Heart Fail Rev ; 26(3): 711-726, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32995973

RESUMO

Even though effective drugs for treating hypertension are available, a great percentage of patients have inadequate control of their blood pressure. Unwanted side effects and inappropriate oral drug adherence are important factors that contribute to the global problem of uncontrolled hypertension. Vaccination could provide a revolutionary therapy with long-lasting effects, increasing patient compliance and therefore better control of high blood pressure. Nowadays, current immunization approaches against hypertension target renin, angiotensin I, angiotensin II, and angiotensin II type 1 receptor, key elements of the renin-angiotensin system. This article reviews the different vaccination attempts with proteins and peptides against the different molecules of the renin-angiotensin system in the last two decades, safety issues, and other novel prospects biomarkers in hypertension, and summarizes the potential of this immunomodulatory approach in clinical practice.


Assuntos
Hipertensão , Vacinas , Pressão Sanguínea , Humanos , Adesão à Medicação , Renina , Sistema Renina-Angiotensina
4.
Pharmacol Res ; 164: 105372, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33316382

RESUMO

Cardiovascular disease continues to be the most common cause of death worldwide. The global burden is so high that numerous organizations are providing counseling recommendations and annual revisions of current pharmacological and non-pharmacological treatments as well as risk prediction for disease prevention and further progression. Although primary preventive interventions targeting risk factors such as obesity, hypertension, smoking, and sedentarism have led to a global decline in hospitalization rates, the aging population has overwhelmed these efforts on a global scale. This review focuses on peptidic vaccines, with the known and not well-known autoantigens in atheroma formation or acquired cardiac diseases, as novel potential immunotherapy approaches to counteract harmful heart disease continuance. We summarize how cancer immunomodulatory strategies started novel approaches to modulate the innate and adaptive immune responses, and how they can be targeted for therapeutic purposes in the cardiovascular system. Brief descriptions focused on the processes that start as either immunologic or non-immunologic, and the ultimate loss of cardiac muscle cell contractility as the outcome, are discussed. We conclude debating how novel strategies with nanoparticles and nanovaccines open a promising therapeutic option to reduce or prevent cardiovascular diseases.


Assuntos
Doenças Cardiovasculares/terapia , Imunoterapia , Vacinas de Subunidades Antigênicas/uso terapêutico , Animais , Autoantígenos/imunologia , Doenças Cardiovasculares/imunologia , Endotélio Vascular , Humanos , Placa Aterosclerótica/prevenção & controle , Sistema Renina-Angiotensina
5.
Molecules ; 26(19)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34641286

RESUMO

Hepatocellular carcinoma (HCC) is the most common form of liver cancer. The number of cases is increasing and the trend for the next few years is not encouraging. HCC is usually detected in the advanced stages of the disease, and pharmacological therapies are not entirely effective. For this reason, it is necessary to search for new therapeutic options. The objective of this work was to evaluate the effect of the drugs isotretinoin and thalidomide on c-MYC expression and cancer-related proteins in an HCC cellular model. The expression of c-MYC was measured using RT-qPCR and western blot assays. In addition, luciferase activity assays were performed for the c-MYC promoters P1 and P2 using recombinant plasmids. Dose-response-time analyses were performed for isotretinoin or thalidomide in cells transfected with the c-MYC promoters. Finally, a proteome profile analysis of cells exposed to these two drugs was performed and the results were validated by western blot. We demonstrated that in HepG2 cells, isotretinoin and thalidomide reduced c-MYC mRNA expression levels, but this decrease in expression was linked to the regulation of P1 and P1-P2 c-MYC promoter activity in isotretinoin only. Thalidomide did not exert any effect on c-MYC promoters. Also, isotretinoin and thalidomide were capable of inducing and repressing proteins associated with cancer. In conclusion, isotretinoin and thalidomide down-regulate c-MYC mRNA expression and this is partially due to P1 or P2 promoter activity, suggesting that these drugs could be promising options for modulating the expression of oncogenes and tumor suppressor genes in HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Isotretinoína/farmacologia , Neoplasias Hepáticas/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Talidomida/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Regiões Promotoras Genéticas , Proteômica/métodos
6.
Artigo em Inglês | MEDLINE | ID: mdl-34040650

RESUMO

BACKGROUND: The COVID-19 crisis is fuelling a state of fear among the human population at global level. Especially, those living in informal settlements and slums worldwide have been profoundly impacted by this pandemic. Individuals living in these places are already leading underprivileged lives. Thus, the economic and mental health problems caused by the COVID-19 crisis have further exacerbated their living standards, which has resulted, for instance, in tragedies such as suicides. OBJECTIVE: In this study, we have sought to identify those individuals most at risk of displaying high levels of fear of COVID-19 in an informal settlement located in the capital city of Peru. METHODS: A questionnaire was administered to 449 inhabitants living in the Carmen Alto informal settlement. The questionnaire was made up of two parts: the first one inquired about demographic data and the second part consisted of the Fear of COVID-19 Scale. RESULTS: The demographic variables of age, gender, marital status, educational level, occupation, whether a relative from the household was infected with COVID-19, and whether one of them died of this showed significant differences. It could be observed as well that the groups of females, stable workers, unemployed and those having completed a workforce education are at higher odds of displaying high levels of fear of COVID-19. As expected, the groups that had either a relative infected with COVID-19 or a relative death by this had the highest levels of fear towards the virus. CONCLUSION: The female participants are more likely to display higher levels of fear of COVID-19 due to the terrible effect that unfavorable events have on them. In the cases of the unemployed and stable workers, their proneness to show high levels of fear towards the virus is because they have lost their incomes, due to the loss of their jobs, and because of fear of infection, respectively. Hence, we hope that this work serves Peruvian (and other) health authorities to develop strategies that help individuals living in informal settlements and are in urgent need of mitigating mental health problems.

7.
J Antimicrob Chemother ; 75(5): 1294-1300, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32030406

RESUMO

OBJECTIVES: We report the results of the reverse transcriptase (RT)/protease (PR) transmitted drug resistance (TDR) prevalence study in 2018, focusing on doravirine resistance-associated mutations and the differences observed when Stanford or French National Agency for AIDS Research (ANRS)/Spanish Network of AIDS Research (RIS)/IAS-USA resistance interpretation algorithms are used to describe clinically relevant resistance. METHODS: We used the WHO 2009 list to investigate the prevalence of NNRTI, NRTI and PI TDR, in treatment-naive HIV-1-infected patients, adding mutations E138A/G/K/Q/R, V106I, V108I, V179L, G190Q, H221Y, F227C/L/V, M230IDR, L234I, P236L and Y318F in RT. The prevalence of doravirine resistance-associated mutations, as described by Soulie et al. in 2019, was evaluated. Clinically relevant TDR was investigated using the latest versions of ANRS, RIS, IAS-USA and Stanford algorithms. RESULTS: NNRTI mutations were detected in 82 of 606 (13.5%) patients. We found 18 patients (3.0%) with NRTI mutations and 5 patients (0.8%) with PI mutations. We detected 11 patients harbouring doravirine resistance-associated mutations (prevalence of 1.8%). Furthermore, we observed important differences in clinically relevant resistance to doravirine when ANRS/RIS (0.7%), IAS-USA (0.5%) or Stanford algorithms (5.0%) were used. V106I, which was detected in 3.8% of the patients, was the main mutation driving these differences. V106I detection was not associated with any of the clinical, demographic or virological characteristics of the patients. CONCLUSIONS: The prevalence of NRTI and PI TDR remains constant in Spain. Doravirine TDR is very infrequent by RIS/ANRS/IAS-USA algorithms, in contrast with results using the Stanford algorithm. Further genotype-phenotype studies are necessary to elucidate the role of V106I in doravirine resistance.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Algoritmos , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Mutação , Prevalência , Piridonas , Espanha , Triazóis
8.
J Antimicrob Chemother ; 74(6): 1693-1700, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30838386

RESUMO

BACKGROUND: Integrase strand-transfer inhibitors (INSTIs) constitute at present one of the pillars of first-line ART. OBJECTIVES: To study the prevalence of and the trend in transmitted drug resistance (TDR) to INSTIs in ART-naive patients in Spain. METHODS: During the period 2012-17, 1109 patients from CoRIS were analysed. The Stanford algorithm v8.7 was used to evaluate TDR and transmission of clinically relevant resistance. To describe individual mutations/polymorphisms, the most recent IAS list (for INSTIs) and the 2009 WHO list update (for the backbone NRTIs used in combination with INSTIs in first-line treatment) were used. RESULTS: Clinically relevant resistance to the INSTI class was 0.2%: T66I, 0.1%, resistance to elvitegravir and intermediate resistance to raltegravir; and G163K, 0.1%, intermediate resistance to raltegravir and elvitegravir. No clinical resistance to dolutegravir or bictegravir was observed. The prevalence of INSTI TDR following the IAS-USA INSTI mutation list was 2.6%, with no trend towards changes in the prevalence throughout the study period. The overall prevalence of NRTI WHO mutations was 4.3%, whereas clinically relevant resistance to tenofovir, abacavir and emtricitabine/lamivudine was 1.7%, 1.9% and 0.7%, respectively. CONCLUSIONS: Given the low prevalence of clinically relevant resistance to INSTIs and first-line NRTIs in Spain, it is very unlikely that a newly diagnosed patient will present with clinical resistance to a first-line INSTI-based regimen. These patients may not benefit from INSTI and NRTI baseline resistance testing.


Assuntos
Farmacorresistência Viral , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Inibidores de Integrase de HIV/farmacologia , Adulto , Idoso , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , Inibidores de Integrase de HIV/uso terapêutico , HIV-1/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Vigilância em Saúde Pública , Espanha/epidemiologia
9.
Bioconjug Chem ; 29(5): 1584-1594, 2018 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-29570280

RESUMO

Cell-to-cell transmission is the most effective pathway for the spread of human immunodeficiency virus (HIV-1). Infected cells expose virus-encoded fusion proteins on their surface as a consequence of HIV-1 replicative cycle that interacts with noninfected cells through CD4 receptor and CXCR4 coreceptor leading to the formation of giant multinucleated cells known as syncytia. Our group previously described the potent activity of dendrimers against CCR5-tropic viruses. Nevertheless, the study of G1-S4, G2-S16, and G3-S16 dendrimers in the context of X4-HIV-1 tropic cell-cell fusion referred to syncytium formation remains still unknown. These dendrimers showed a suitable biocompatibility in all cell lines studied and our results demonstrated that anionic carbosilane dendrimers G1-S4, G2-S16, and G3-S16 significantly inhibit the X4-HIV-1 infection, as well as syncytia formation, in a dose dependent manner. We also demonstrated that G2-S16 and G1-S4 significantly reduced syncytia formation in HIV-1 Env-mediated cell-to-cell fusion model. Molecular modeling and in silico models showed that G2-S16 dendrimer interfered with gp120-CD4 complex and demonstrated its potential use for a treatment.


Assuntos
Fármacos Anti-HIV/farmacologia , Dendrímeros/farmacologia , Proteína gp120 do Envelope de HIV/metabolismo , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Silanos/farmacologia , Internalização do Vírus/efeitos dos fármacos , Ânions/química , Ânions/farmacologia , Fármacos Anti-HIV/química , Antígenos CD4/metabolismo , Linhagem Celular , Dendrímeros/química , Infecções por HIV/metabolismo , HIV-1/fisiologia , Humanos , Modelos Moleculares , Silanos/química
10.
Sensors (Basel) ; 18(5)2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29747374

RESUMO

The evoked potential is a neuronal activity that originates when a stimulus is presented. To achieve its detection, various techniques of brain signal processing can be used. One of the most studied evoked potentials is the P300 brain wave, which usually appears between 300 and 500 ms after the stimulus. Currently, the detection of P300 evoked potentials is of great importance due to its unique properties that allow the development of applications such as spellers, lie detectors, and diagnosis of psychiatric disorders. The present study was developed to demonstrate the usefulness of the Stockwell transform in the process of identifying P300 evoked potentials using a low-cost electroencephalography (EEG) device with only two brain sensors. The acquisition of signals was carried out using the Emotiv EPOC® device—a wireless EEG headset. In the feature extraction, the Stockwell transform was used to obtain time-frequency information. The algorithms of linear discriminant analysis and a support vector machine were used in the classification process. The experiments were carried out with 10 participants; men with an average age of 25.3 years in good health. In general, a good performance (75⁻92%) was obtained in identifying P300 evoked potentials.


Assuntos
Encéfalo/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados P300/fisiologia , Adulto , Interfaces Cérebro-Computador , Análise Discriminante , Eletrodos , Eletroencefalografia/economia , Humanos , Masculino , Processamento de Sinais Assistido por Computador , Máquina de Vetores de Suporte , Tecnologia sem Fio , Adulto Jovem
11.
P R Health Sci J ; 37(1): 39-45, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29547683

RESUMO

OBJECTIVE: Colorectal cancer (CRC) is a leading causes of cancer death among men and women. The purpose of this study was to determine the prevalence of oligopolyposis (≥20 synchronous colorectal adenomas) and its associated clinicopathological characteristics in Hispanics with incident CRC. METHODS: Pathology reports from individuals diagnosed with CRC (2007 to 2011) were obtained from the PR Central Cancer Registry. Colorectal polyp burden was calculated using pathology reports and the data was normalized to colon segment size. Comparisons of demographic and clinicopathological characteristics by synchronous oligopolyposis status (<20 vs. <= *20) were performed using the chi-square or Fisher's exact test. Multivariate logistic regression models were fitted to estimate the adjusted prevalence odds ratios (aPOR), with 95% confidence intervals (CI). All analyses were performed using Stata (v.12.0). RESULTS: Analyses of 1,573 colectomy specimens was performed. Oligopolyposis was observed in 9.47% (149 of 1,573) of the subjects with incident CRC. Increasing age (aPOR50-64 = 1.72, 95% CI: 0.59-5.02; aPOR65-74 = 1.83, 95% CI: 0.64-5.27; aPOR≥75 = 2.67, 95% CI: 0.93-7.64) and proximal CRC tumor location (POR = 2.91, 95% CI:1.98-4.30) were significantly associated with having oligopolyposis at CRC diagnosis. However, subjects diagnosed with CRC at a regional stage (aPORRegional = 0.50, 95% CI: 0.32-0.79) or distant stage (aPORDistant = 0.45, 95% CI: 0.29-0.69) were less likely to have synchronous oligopolyposis (p<0.05). CONCLUSION: Our findings suggest that genetic syndromes associated with colorectal polyposis may be implicated in a higher than expected number of CRC cases. Individuals with CRC and synchronous oligopolyposis should receive genetic counseling.


Assuntos
Polipose Adenomatosa do Colo/epidemiologia , Neoplasias Colorretais/epidemiologia , Neoplasias Primárias Múltiplas/epidemiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos
12.
Gac Med Mex ; 154(5): 561-568, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-30407454

RESUMO

INTRODUCTION: Retinopathy of prematurity (ROP) is a disease where retinal blood vessels do not develop normally and may cause visual damage and blindness. OBJECTIVE: To determine the frequency and severity of ROP in preterm newborns. METHOD: A descriptive, comparative study was carried out within the 2009-2013 period. Patients' general characteristics were recorded, including gestational age and postmenstrual age at the moment of ophthalmologic examination, as well as ROP severity and type of treatment. RESULTS: A total of 326 preterm newborns were included: 47.8 % (n = 156) had ROP; in 21.1 % it was severe (stage ≥ 3). Median gestational age was 28 weeks in preterm newborns with ROP, median birth weight was 1000 g, and median postmenstrual age at ophthalmological examination was 36 weeks. Of the infants with ROP, 71.1 % received treatment: 63.4 % of those who had mild ROP and 100 % of those with severe ROP. CONCLUSIONS: ROP frequency was high, higher than that reported in developed countries and similar to that in developing countries. The frequency of severe ROP was also higher. It is necessary for effective programs for the detection and opportune treatment of ROP to be established.


INTRODUCCIÓN: La retinopatía del prematuro (ROP) es una enfermedad en la que los vasos sanguíneos de la retina no se desarrollan normalmente, lo que puede ocasionar daño visual y ceguera. OBJETIVO: Identificar la frecuencia y gravedad de la ROP en recién nacidos prematuros. MÉTODO: Estudio descriptivo comparativo realizado en el periodo 2009-2013. Se registraron características generales de los pacientes, edad posnatal y edad posconcepcional al momento de la exploración oftalmológica, así como gravedad y tratamiento de la ROP. RESULTADOS: Se incluyeron 326 recién nacidos prematuros: 47.8 % (n = 156) tuvo ROP, en 21.1 % fue grave (estadio ≥ 3). La mediana de la edad gestacional fue de 28 semanas en los recién nacidos prematuros con ROP, el peso al nacer fue de 1000 g y la edad posconcepcional a la exploración oftalmológica fue de 36 semanas. De los niños con ROP, 71.1 % recibió tratamiento, 63.4 % de aquellos que tuvieron ROP leve y 100 % de aquellos con ROP grave. CONCLUSIONES: La frecuencia de ROP fue alta, mayor a la reportada en los países desarrollados y similar a la de otros países en desarrollo. La frecuencia de ROP grave también fue mayor. Es necesario establecer programas efectivos de detección y tratamiento oportuno de ROP.


Assuntos
Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Retinopatia da Prematuridade/epidemiologia , Peso ao Nascer , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , México/epidemiologia , Retinopatia da Prematuridade/fisiopatologia , Índice de Gravidade de Doença
13.
Am J Physiol Heart Circ Physiol ; 312(4): H645-H661, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28130337

RESUMO

Recent evidence has shown that nanoparticles that have been used to improve or create new functional properties for common products may pose potential risks to human health. Silicon dioxide (SiO2) has emerged as a promising therapy vector for the heart. However, its potential toxicity and mechanisms of damage remain poorly understood. This study provides the first exploration of SiO2-induced toxicity in cultured cardiomyocytes exposed to 7- or 670-nm SiO2 particles. We evaluated the mechanism of cell death in isolated adult cardiomyocytes exposed to 24-h incubation. The SiO2 cell membrane association and internalization were analyzed. SiO2 showed a dose-dependent cytotoxic effect with a half-maximal inhibitory concentration for the 7 nm (99.5 ± 12.4 µg/ml) and 670 nm (>1,500 µg/ml) particles, which indicates size-dependent toxicity. We evaluated cardiomyocyte shortening and intracellular Ca2+ handling, which showed impaired contractility and intracellular Ca2+ transient amplitude during ß-adrenergic stimulation in SiO2 treatment. The time to 50% Ca2+ decay increased 39%, and the Ca2+ spark frequency and amplitude decreased by 35 and 21%, respectively, which suggest a reduction in sarcoplasmic reticulum Ca2+-ATPase (SERCA) activity. Moreover, SiO2 treatment depolarized the mitochondrial membrane potential and decreased ATP production by 55%. Notable glutathione depletion and H2O2 generation were also observed. These data indicate that SiO2 increases oxidative stress, which leads to mitochondrial dysfunction and low energy status; these underlie reduced SERCA activity, shortened Ca2+ release, and reduced cell shortening. This mechanism of SiO2 cardiotoxicity potentially plays an important role in the pathophysiology mechanism of heart failure, arrhythmias, and sudden death.NEW & NOTEWORTHY Silica particles are used as novel nanotechnology-based vehicles for diagnostics and therapeutics for the heart. However, their potential hazardous effects remain unknown. Here, the cardiotoxicity of silica nanoparticles in rat myocytes has been described for the first time, showing an impairment of mitochondrial function that interfered directly with Ca2+ handling.


Assuntos
Cálcio/metabolismo , Cardiotoxicidade/metabolismo , Metabolismo Energético/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Nanopartículas/toxicidade , Dióxido de Silício/toxicidade , Trifosfato de Adenosina/metabolismo , Animais , Membrana Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Cardíacas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
14.
J Bioenerg Biomembr ; 48(1): 43-54, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26739598

RESUMO

Copper-based drugs, Casiopeinas (Cas), exhibit antiproliferative and antineoplastic activities in vitro and in vivo, respectively. Unfortunately, the clinical use of these novel chemotherapeutics could be limited by the development of dose-dependent cardiotoxicity. In addition, the molecular mechanisms underlying Cas cardiotoxicity and anticancer activity are not completely understood. Here, we explore the potential impact of Cas on the cardiac mitochondria energetics as the molecular mechanisms underlying Cas-induced cardiotoxicity. To explore the properties on mitochondrial metabolism, we determined Cas effects on respiration, membrane potential, membrane permeability, and redox state in isolated cardiac mitochondria. The effect of Cas on the mitochondrial membrane potential (Δψm) was also evaluated in isolated cardiomyocytes by confocal microscopy and flow cytometry. Cas IIIEa, IIgly, and IIIia predominately inhibited maximal NADH- and succinate-linked mitochondrial respiration, increased the state-4 respiration rate and reduced membrane potential, suggesting that Cas also act as mitochondrial uncouplers. Interestingly, cyclosporine A inhibited Cas-induced mitochondrial depolarization, suggesting the involvement of mitochondrial permeability transition pore (mPTP). Similarly to isolated mitochondria, in isolated cardiomyocytes, Cas treatment decreased the Δψm and cyclosporine A treatment prevented mitochondrial depolarization. The production of H2O2 increased in Cas-treated mitochondria, which might also increase the oxidation of mitochondrial proteins such as adenine nucleotide translocase. In accordance, an antioxidant scavenger (Tiron) significantly diminished Cas IIIia mitochondrial depolarization. Cas induces a prominent loss of membrane potential, associated with alterations in redox state, which increases mPTP opening, potentially due to thiol-dependent modifications of the pore, suggesting that direct or indirect inhibition of mPTP opening might reduce Cas-induced cardiotoxicity.


Assuntos
Antineoplásicos , Cobre , Mitocôndrias Cardíacas/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Cobre/efeitos adversos , Cobre/farmacologia , Mitocôndrias Cardíacas/patologia , Miócitos Cardíacos/patologia , Permeabilidade/efeitos dos fármacos , Ratos
15.
Am J Physiol Heart Circ Physiol ; 308(5): H467-77, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25527782

RESUMO

Stress-induced cardiomyopathy, triggered by acute catecholamine discharge, is a syndrome characterized by transient, apical ballooning linked to acute heart failure and ventricular arrhythmias. Rats receiving an acute isoproterenol (ISO) overdose (OV) suffer cardiac apex ischemia-reperfusion damage and arrhythmia, and then undergo cardiac remodeling and dysfunction. Nevertheless, the subcellular mechanisms underlying cardiac dysfunction after acute damage subsides are not thoroughly understood. To address this question, Wistar rats received a single ISO injection (67 mg/kg). We found in vivo moderate systolic and diastolic dysfunction at 2 wk post-ISO-OV; however, systolic dysfunction recovered after 4 wk, while diastolic dysfunction worsened. At 2 wk post-ISO-OV, cardiac function was assessed ex vivo, while mitochondrial oxidative metabolism and stress were assessed in vitro, and Ca(2+) handling in ventricular myocytes. These were complemented with sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA), phospholamban (PLB), and RyR2 expression studies. Ex vivo, basal mechanical performance index (MPI) and oxygen consumption rate (MVO2) were unchanged. Nevertheless, upon increase of metabolic demand, by ß-adrenergic stimulation (1-100 nM ISO), the MPI versus MVO2 relation decreased and shifted to the right, suggesting MPI and mitochondrial energy production uncoupling. Mitochondria showed decreased oxidative metabolism, membrane fragility, and enhanced oxidative stress. Myocytes presented systolic and diastolic Ca(2+) mishandling, and blunted response to ISO (100 nM), and all these without apparent changes in SERCA, PLB, or RyR2 expression. We suggest that post-ISO-OV mitochondrial dysfunction may underlie decreased cardiac contractility, mainly by depletion of ATP needed for myofilaments and Ca(2+) transport by SERCA, while exacerbated oxidative stress may enhance diastolic RyR2 activity.


Assuntos
Sinalização do Cálcio , Cardiomiopatias/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Estresse Oxidativo , Agonistas Adrenérgicos/toxicidade , Animais , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Cardiomiopatias/etiologia , Cardiomiopatias/fisiopatologia , Células Cultivadas , Ventrículos do Coração/citologia , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Isoproterenol/toxicidade , Camundongos , Mitocôndrias Cardíacas/metabolismo , Contração Miocárdica , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Consumo de Oxigênio , Ratos , Ratos Wistar , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
16.
Soc Stud Sci ; 45(6): 797-815, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27479997

RESUMO

This article provides a comparison between genomic medicine and forensic genetics in Mexico, in light of recent depictions of the nation as a 'país de gordos' (country of the fat) and a 'país de muertos' (country of the dead). We examine the continuities and ruptures in the public image of genetics in these two areas of attention, health and security, focusing especially on how the relevant publics of genetic science are assembled in each case. Publics of biomedical and forensic genetics are assembled through processes of recruitment and interpellation, in ways that modulate current theorizations of co-production. The comparison also provides a vista onto discussions regarding the involvement of genetics in regimes of governance and citizenship and about the relationship between the state and biopower in a context of perceived health crisis and war-like violence.


Assuntos
Morte , Genética Forense , Genética Médica , Obesidade/genética , Obesidade/prevenção & controle , Humanos , México , Obesidade/psicologia
17.
Soc Stud Sci ; 45(6): 775-96, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27479996

RESUMO

The articles in this issue highlight contributions that studies of Latin America can make to wider debates about the effects of genomic science on public ideas about race and nation. We argue that current ideas about the power of genomics to transfigure and transform existing ways of thinking about human diversity are often overstated. If a range of social contexts are examined, the effects are uneven. Our data show that genomic knowledge can unsettle and reinforce ideas of nation and race; it can be both banal and highly politicized. In this introduction, we outline concepts of genetic knowledge in society; theories of genetics, nation and race; approaches to public understandings of science; and the Latin American contexts of transnational ideas of nation and race.


Assuntos
Genômica , Grupos Raciais/psicologia , Humanos , América Latina
18.
Soc Stud Sci ; 45(6): 839-61, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27479999

RESUMO

This article explores the relationship between genetic research, nationalism and the construction of collective social identities in Latin America. It makes a comparative analysis of two research projects--the 'Genoma Mexicano' and the 'Homo Brasilis'--both of which sought to establish national and genetic profiles. Both have reproduced and strengthened the idea of their respective nations of focus, incorporating biological elements into debates on social identities. Also, both have placed the unifying figure of the mestizo/mestiço at the heart of national identity constructions, and in so doing have displaced alternative identity categories, such as those based on race. However, having been developed in different national contexts, these projects have had distinct scientific and social trajectories: in Mexico, the genomic mestizo is mobilized mainly in relation to health, while in Brazil the key arena is that of race. We show the importance of the nation as a frame for mobilizing genetic data in public policy debates, and demonstrate how race comes in and out of focus in different Latin American national contexts of genomic research, while never completely disappearing.


Assuntos
Cultura , Saúde Pública , Política Pública , Grupos Raciais , Identificação Social , Brasil , Pesquisa em Genética , Humanos , México
19.
Sensors (Basel) ; 14(11): 20645-66, 2014 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-25365462

RESUMO

In this article, a toolbox based on a monitoring and control interface (MCI) is presented and applied in a heat exchanger. The MCI was programed in order to realize sensor fault detection and isolation and fault tolerance using virtual sensors. The virtual sensors were designed from model-based high-gain observers. To develop the control task, different kinds of control laws were included in the monitoring and control interface. These control laws are PID, MPC and a non-linear model-based control law. The MCI helps to maintain the heat exchanger under operation, even if a temperature outlet sensor fault occurs; in the case of outlet temperature sensor failure, the MCI will display an alarm. The monitoring and control interface is used as a practical tool to support electronic engineering students with heat transfer and control concepts to be applied in a double-pipe heat exchanger pilot plant. The method aims to teach the students through the observation and manipulation of the main variables of the process and by the interaction with the monitoring and control interface (MCI) developed in LabVIEW©. The MCI provides the electronic engineering students with the knowledge of heat exchanger behavior, since the interface is provided with a thermodynamic model that approximates the temperatures and the physical properties of the fluid (density and heat capacity). An advantage of the interface is the easy manipulation of the actuator for an automatic or manual operation. Another advantage of the monitoring and control interface is that all algorithms can be manipulated and modified by the users.

20.
Biomolecules ; 14(3)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38540672

RESUMO

As temperatures continue to modify due to weather changes, more regions are being exposed to extreme heat and cold. Physiological distress due to low and high temperatures can affect the heart, blood vessels, liver, and especially, the kidneys. Dehydration causes impaired cell function and heat itself triggers cellular stress. The decline in circulating plasma volume by sweat, which stresses the renal and cardiovascular systems, has been related to some molecules that are crucial players in preventing or provoking cellular damage. Hypovolemia and blood redistribution to cutaneous blood vessels reduce perfusion to the kidney triggering the activation of the renin-angiotensin-aldosterone system. In this review, we expose a deeper understanding of the modulation of molecules that interact with other proteins in humans to provide significant findings in the context of extreme heat and cold environments and renal damage reversal. We focus on the molecular changes exerted by temperature and dehydration in the renal system as both parameters are heavily implicated by weather change (e.g., vasopressin-induced fructose uptake, fructogenesis, and hypertension). We also discuss the compensatory mechanisms activated under extreme temperatures that can exert further kidney injury. To finalize, we place special emphasis on the renal mechanisms of protection against temperature extremes, focusing on two important protein groups: heat shock proteins and sirtuins.


Assuntos
Desidratação , Nefropatias , Humanos , Desidratação/metabolismo , Mudança Climática , Rim/metabolismo , Nefropatias/etiologia , Nefropatias/metabolismo , Temperatura
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