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1.
Am J Physiol Heart Circ Physiol ; 326(3): H760-H771, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241008

RESUMO

Increased sitting time, the most common form of sedentary behavior, is an independent risk factor for all-cause and cardiovascular disease mortality; however, the mechanisms linking sitting to cardiovascular risk remain largely elusive. Studies over the last decade have led to the concept that excessive time spent in the sitting position and the ensuing reduction in leg blood flow-induced shear stress cause endothelial dysfunction. This conclusion has been mainly supported by studies using flow-mediated dilation in the lower extremities as the measured outcome. In this review, we summarize evidence from classic studies and more recent ones that collectively support the notion that prolonged sitting-induced leg vascular dysfunction is likely also attributable to changes occurring in vascular smooth muscle cells (VSMCs). Indeed, we provide evidence that prolonged constriction of resistance arteries can lead to modifications in the structural characteristics of the vascular wall, including polymerization of actin filaments in VSMCs and inward remodeling, and that these changes manifest in a time frame that is consistent with the vascular changes observed with prolonged sitting. We expect this review will stimulate future studies with a focus on VSMC cytoskeletal remodeling as a potential target to prevent the detrimental vascular ramifications of too much sitting.


Assuntos
Postura Sentada , Doenças Vasculares , Humanos , Perna (Membro)/irrigação sanguínea , Postura/fisiologia , Endotélio Vascular , Extremidade Inferior/irrigação sanguínea , Vasodilatação/fisiologia
2.
Am J Physiol Heart Circ Physiol ; 326(1): H270-H277, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37999645

RESUMO

Endothelial insulin resistance represents a causal factor in the pathogenesis of type 2 diabetes (T2D) and vascular disease, thus the need to identify molecular mechanisms underlying defects in endothelial insulin signaling. We previously have shown that a disintegrin and metalloproteinase-17 (ADAM17) is increased while insulin receptor α-subunit (IRα) is decreased in the vasculature of patients with T2D, leading to impaired insulin-induced vasodilation. We have also demonstrated that ADAM17 sheddase activity targets IRα; however, the mechanisms driving endothelial ADAM17 activity in T2D are largely unknown. Herein, we report that externalization of phosphatidylserine (PS) to the outer leaflet of the plasma membrane causes ADAM17-mediated shedding of IRα and blunting of insulin signaling in endothelial cells. Furthermore, we demonstrate that endothelial PS externalization is mediated by the phospholipid scramblase anoctamin-6 (ANO6) and that this process can be stimulated by neuraminidase, a soluble enzyme that cleaves sialic acid residues. Of note, we demonstrate that men and women with T2D display increased levels of neuraminidase activity in plasma, relative to age-matched healthy individuals, and this occurs in conjunction with increased ADAM17 activity and impaired leg blood flow responses to endogenous insulin. Collectively, this work reveals the neuraminidase-ANO6-ADAM17 axis as a novel potential target for restoring endothelial insulin sensitivity in T2D.NEW & NOTEWORTHY This work provides the first evidence that neuraminidase, an enzyme increased in the circulation of men and women with type 2 diabetes (T2D), promotes anoctamin-6 (ANO6)-dependent externalization of phosphatidylserine in endothelial cells, which in turn leads to activation of a disintegrin and metalloproteinase-17 (ADAM17) and consequent shedding of the insulin receptor-α from the cell surface. Hence, this work supports that consideration should be given to the neuraminidase-ANO6-ADAM17 axis as a novel potential target for restoring endothelial insulin sensitivity in T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Masculino , Humanos , Feminino , Células Endoteliais/metabolismo , Receptor de Insulina/metabolismo , Fosfatidilserinas/metabolismo , Neuraminidase/metabolismo , Insulina/metabolismo , Desintegrinas , Proteína ADAM17/metabolismo , Anoctaminas/metabolismo
3.
Phytopathology ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748545

RESUMO

Citrus canker disease, caused by Xanthomonas citri subsp. citri, poses a significant threat to global citrus production. The control of the disease in the field relies mainly on the use of conventional tools such as copper compounds, which are harmful to the environment and could lead to bacterial resistance. This scenario stresses the need for new and sustainable technologies to control phytopathogens, representing a key challenge in developing studies that translate basic into applied knowledge. During infection, X. citri subsp. citri secretes a transcriptional activator-like effector that enters the nucleus of plant cells, activating the expression of the canker susceptibility gene LATERAL ORGAN BOUNDARIES 1 (LOB1). In this study, we explored the use of antisense oligonucleotides (ASOs) with phosphorothioate modifications to transiently inhibit the gene expression of CsLOB1 in Citrus sinensis. We designed and validated three potential ASO sequences, which led to a significant reduction in disease symptoms compared to the control. The selected ASO3-CsLOB1 significantly decreased the expression level of CsLOB1 when delivered through two distinct delivery methods and the reduction of the symptoms ranged from approximately 15% to 83%. Notably, plants treated with ASO3 did not exhibit an increase in symptoms development over the evaluation period. This study highlights the efficacy of ASO technology, based on short oligonucleotide chemically modified sequences, as a promising tool for controlling phytopathogens without the need for genetic transformation or plant regeneration. Our results demonstrate the potential of ASOs as a biotechnological tool for the management of citrus canker disease.

4.
Am J Physiol Regul Integr Comp Physiol ; 324(3): R293-R304, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36622084

RESUMO

Vascular insulin resistance, a major characteristic of obesity and type 2 diabetes (T2D), manifests with blunting of insulin-induced vasodilation. Although there is evidence that females are more whole body insulin sensitive than males in the healthy state, whether sex differences exist in vascular insulin sensitivity is unclear. Also uncertain is whether weight loss can reestablish vascular insulin sensitivity in T2D. The purpose of this investigation was to 1) establish if sex differences in vasodilatory responses to insulin exist in absence of disease, 2) determine whether female sex affords protection against the development of vascular insulin resistance with long-term overnutrition and obesity, and 3) examine if diet-induced weight loss can restore vascular insulin sensitivity in men and women with T2D. First, we show in healthy mice and humans that sex does not influence insulin-induced femoral artery dilation and insulin-stimulated leg blood flow, respectively. Second, we provide evidence that female mice are protected against impairments in insulin-induced dilation caused by overnutrition-induced obesity. Third, we show that men and women exhibit comparable levels of vascular insulin resistance when T2D develops but that diet-induced weight loss is effective at improving insulin-stimulated leg blood flow, particularly in women. Finally, we provide indirect evidence that these beneficial effects of weight loss may be mediated by a reduction in endothelin-1. In aggregate, the present data indicate that female sex confers protection against obesity-induced vascular insulin resistance and provide supportive evidence that, in women with T2D, vascular insulin resistance can be remediated with diet-induced weight loss.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Humanos , Feminino , Masculino , Camundongos , Animais , Resistência à Insulina/fisiologia , Insulina , Obesidade , Redução de Peso , Artéria Femoral , Dieta
5.
J Sex Med ; 20(6): 742-748, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37037776

RESUMO

BACKGROUND: Early-life stress affects physiological development and produces changes in various aspects of emotional behavior. AIM: We sought to examine the effects of double perinatal stress (DPS)-a combination of prenatal systemic hypoxic-ischemic (HI) insults and repeated early maternal separation-on the estrus cycle and sexual behavior of adult rats. METHODS: HI was induced by clamping the uterine arteries of pregnant rats for 45 minutes on the 18th day of gestation (HI group). Sham control animals received laparotomy and anesthesia only. Pups were born at term. Maternal separation was performed from postnatal day 1 (P1) (P0 = day of birth) to P15. At P90, the sexual response of females in estrus was evaluated. Statistical analysis was performed using 2-way analysis of variance followed by Tukey's test. OUTCOMES: We considered the estrous cycle and sexual behavior of female rats submitted to DPS, as well as the influence of female behavior on the sexual response of male rats. RESULTS: Rats submitted to DPS showed a reduction in the lordosis quotient and in the lordosis rate, suggesting a reduction in female sexual receptivity. DPS female rats showed a reduction in the number of hops and darts and in the genital exploration time rate, suggesting a reduction in sexual proceptivity. In addition, males that interacted with DPS females showed a reduction in the number of ejaculations and in copulatory efficiency. CLINICAL IMPLICATIONS: Developing a deeper understanding of perinatal factors that affect adult female sexual response will allow for more effective interventions to prevent and treat such changes. On the other hand, the analysis of the sexual response allows assessing the quality of life and the general state of health. STRENGTHS AND LIMITATIONS: The development of animal models to investigate the environmental factors that interfere in the female sexual response may allow researchers to propose and test new therapeutic strategies. On the other hand, care must be exercised when interpreting animal data and extrapolating these results to estimate the possible effects of perinatal stressors on the human sexual response. CONCLUSION: Our results revealed that females subjected to DPS showed long-term effects on sexual behavior. In conclusion, managing stressors in prenatal life and early postnatal life can prevent problems in adult sexual life and improve overall health.


Assuntos
Lordose , Privação Materna , Humanos , Gravidez , Ratos , Animais , Masculino , Feminino , Ratos Wistar , Qualidade de Vida , Comportamento Sexual Animal/fisiologia , Comportamento Sexual
6.
Virus Genes ; 59(4): 562-571, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37195404

RESUMO

The feline leukemia virus (FeLV) belongs to the Retroviridae family and Gammaretrovirus genus, and causes a variety of neoplastic and non-neoplastic diseases in domestic cats (Felis catus), such as thymic and multicentric lymphomas, myelodysplastic syndromes, acute myeloid leukemia, aplastic anemia, and immunodeficiency. The aim of the present study was to carry out the molecular characterization of FeLV-positive samples and determine the circulating viral subtype in the city of São Luís, Maranhão, Brazil, as well as identify its phylogenetic relationship and genetic diversity. The FIV Ac/FeLV Ag Test Kit (Alere™) and the commercial immunoenzymatic assay kit (Alere™) were used to detect the positive samples, which were subsequently confirmed by ELISA (ELISA - SNAP® Combo FeLV/FIV). To confirm the presence of proviral DNA, a polymerase chain reaction (PCR) was performed to amplify the target fragments of 450, 235, and 166 bp of the FeLV gag gene. For the detection of FeLV subtypes, nested PCR was performed for FeLV-A, B, and C, with amplification of 2350-, 1072-, 866-, and 1755-bp fragments for the FeLV env gene. The results obtained by nested PCR showed that the four positive samples amplified the A and B subtypes. The C subtype was not amplified. There was an AB combination but no ABC combination. Phylogenetic analysis revealed similarities (78% bootstrap) between the subtype circulating in Brazil and FeLV-AB and with the subtypes of Eastern Asia (Japan) and Southeast Asia (Malaysia), demonstrating that this subtype possesses high genetic variability and a differentiated genotype.


Assuntos
Doenças do Gato , Vírus da Imunodeficiência Felina , Gatos , Animais , Vírus da Leucemia Felina/genética , Brasil , Filogenia , Genótipo , Reação em Cadeia da Polimerase/veterinária , Vírus da Imunodeficiência Felina/genética
7.
Platelets ; 34(1): 2139821, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36377063

RESUMO

Exercise training (ET) can lower platelet reactivity in patients with cardiovascular risk factors. However, the effects of ET on platelet reactivity in higher-risk patients is unknown. The aim of this study was to evaluate the effects of ET on platelet reactivity in patients with recent myocardial infarction (MI). Ninety patients were randomly assigned 1 month post-MI to the intervention (patients submitted to a supervised ET program) or control group. All patients were on dual antiplatelet therapy (DAPT). Platelet reactivity by VerifyNow-P2Y12 (measured by P2Y12 reaction units - PRUs) test was determined at baseline and at the end of 14 ± 2 weeks of follow-up at rest (primary endpoint), and multiplate electrode aggregometry (MEA) adenosine diphosphate (ADP) and aspirin (ASPI) tests were performed immediately before and after the maximal cardiopulmonary exercise test (CPET) at the same time points (secondary endpoints). Sixty-five patients (mean age 58.9 ± 10 years; 73.8% men; 60% ST elevation MI) completed follow-up (control group, n = 31; intervention group, n = 34). At the end of the follow-up, the mean platelet reactivity was 172.8 ± 68.9 PRUs and 166.9 ± 65.1 PRUs for the control and intervention groups, respectively (p = .72). Platelet reactivity was significantly increased after the CPET compared to rest at the beginning and at the end of the 14-week follow-up (among the intervention groups) by the MEA-ADP and MEA-ASPI tests (p < .01 for all analyses). In post-MI patients on DAPT, 14 weeks of supervised ET did not reduce platelet reactivity. Moreover, platelet reactivity was increased after high-intensity exercise (ClinicalTrials.gov: NCT02958657; https://clinicaltrials.gov/ct2/show/NCT02958657).


What is the context? Platelet reactivity is reduced after exercise training in healthy individuals and patients with cardiovascular risk factors, but the effect in higher-risk patients is unknown.High-intensity exercise in untrained individuals increases platelet reactivity. The effect of dual antiplatelet therapy in inhibiting exercise-induced hyperreactivity is poorly understood.What's new?Exercise training did not reduce platelet reactivity in post-myocardial infarction patients.High-intensity exercise increased platelet reactivity in post-myocardial infarction patients on dual antiplatelet therapy.Exercise training did not attenuate the exercise-induced increase in platelet reactivity.What's the impact?The study suggests that strenuous exercise, if indicated, should be applied carefully to patients with high risk of recurrent ischemic events, even if on optimal medical therapy and after being trained.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Inibidores da Agregação Plaquetária/efeitos adversos , Plaquetas , Infarto do Miocárdio/tratamento farmacológico , Aspirina/efeitos adversos , Difosfato de Adenosina/farmacologia , Intervenção Coronária Percutânea/efeitos adversos , Agregação Plaquetária
8.
Arch Pharm (Weinheim) ; 356(4): e2200472, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36534890

RESUMO

Chagas disease (CD) is a neglected disease caused by the protozoan Trypanosoma cruzi. The two drugs used in the treatment schedules exhibit adverse effects and severe toxicity. Thus, searching for new antitrypanosomal agents is urgent to provide improved treatments to those affected by this disease. 5-Nitrofuran-isoxazole analogs were synthesized by cycloaddition reactions [3+2] between chloro-oximes and acetylenes in satisfactory yields. We analyzed the structure-activity relationship of the analogs based on Hammett's and Hansch's parameters. The 5-nitrofuran-isoxazole analogs exhibited relevant in vitro antitrypanosomal activity against the amastigote forms of T. cruzi. Analog 7s was the trending hit of the series, showing an IC50 value of 40 nM and a selectivity index of 132.50. A possible explanation for this result may be the presence of an electrophile near the isoxazole core. Moreover, the most active analogs proved to act as an in vitro substrate of type I nitroreductase rather than the cruzain, enzymes commonly investigated in molecular target studies of CD drug discovery. These findings suggest that 5-nitrofuran-isoxazole analogs are promising in the studies of agents for CD treatment.


Assuntos
Nitrofuranos , Tripanossomicidas , Trypanosoma cruzi , Relação Estrutura-Atividade , Isoxazóis/farmacologia , Isoxazóis/química , Reposicionamento de Medicamentos , Nitrofuranos/farmacologia , Nitrofuranos/química , Tripanossomicidas/farmacologia , Tripanossomicidas/química
9.
Int Wound J ; 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37904609

RESUMO

Wound care is a complex procedure and the related research may include many variables. Deficiencies in the sample inclusion and exclusion criteria may limit the generalizability of randomized controlled trials (RCTs) for wound patients in the real world. This study aimed to evaluate deficiencies in reporting the inclusion and exclusion criteria and the characteristics of patients in RCTs of pressure injuries (PI) therapeutic interventions. We conducted a systematic methodological review in which 40 full text RCTs of PI treatment interventions published in English, from 2008 to 2020, were identified. Data on the general characteristics of the included RCTs and data about inclusion/exclusion criteria and characteristics of patients were collected. The inclusion/exclusion criteria were categorized into five domains (definition of disease, precision, safety, ethical/legal and administrative). Study duration (in weeks) was 8.0 (quartile 1: 2.0; quartile 3: 48.0); only 5.0% of the trials mentioned race, skin colour or ethnicity, and 37.5% reported the duration of the wound. Only 9 (22.5%) studies reported the drugs that the included patients were using and 10 (25.0%) RCTs reported adverse events. The presence of the five domains was observed only in 12.5% of RCTs and only 12 (30.0%) had the precision domain. Much more research is required in systematic assessments of the external validity of trials because there is substantial disparity between the information that is provided by RCTs and the information that is required by clinicians. We concluded that there are deficiencies in reporting of data related to inclusion/exclusion criteria and characteristics of patients of RCTs assessing PI therapeutic interventions.

10.
Am J Physiol Heart Circ Physiol ; 322(2): H167-H180, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34890280

RESUMO

Consumption of diets high in fat, sugar, and salt (Western diet, WD) is associated with accelerated arterial stiffening, a major independent risk factor for cardiovascular disease (CVD). Women with obesity are more prone to develop arterial stiffening leading to more frequent and severe CVD compared with men. As tissue transglutaminase (TG2) has been implicated in vascular stiffening, our goal herein was to determine the efficacy of cystamine, a nonspecific TG2 inhibitor, at reducing vascular stiffness in female mice chronically fed a WD. Three experimental groups of female mice were created. One was fed regular chow diet (CD) for 43 wk starting at 4 wk of age. The second was fed a WD for the same 43 wk, whereas a third cohort was fed WD, but also received cystamine (216 mg/kg/day) in the drinking water during the last 8 wk on the diet (WD + C). All vascular stiffness parameters assessed, including aortic pulse wave velocity and the incremental modulus of elasticity of isolated femoral and mesenteric arteries, were significantly increased in WD- versus CD-fed mice, and reduced in WD + C versus WD-fed mice. These changes coincided with respectively augmented and diminished vascular wall collagen and F-actin content, with no associated effect in blood pressure. In cultured human vascular smooth muscle cells, cystamine reduced TG2 activity, F-actin:G-actin ratio, collagen compaction capacity, and cellular stiffness. We conclude that cystamine treatment represents an effective approach to reduce vascular stiffness in female mice in the setting of WD consumption, likely because of its TG2 inhibitory capacity.NEW & NOTEWORTHY This study evaluates the novel role of transglutaminase 2 (TG2) inhibition to directly treat vascular stiffness. Our data demonstrate that cystamine, a nonspecific TG2 inhibitor, improves vascular stiffness induced by a diet rich in fat, fructose, and salt. This research suggests that TG2 inhibition might bear therapeutic potential to reduce the disproportionate burden of cardiovascular disease in females in conditions of chronic overnutrition.


Assuntos
Cistamina/farmacologia , Dieta Ocidental/efeitos adversos , Inibidores Enzimáticos/farmacologia , Proteína 2 Glutamina gama-Glutamiltransferase/antagonistas & inibidores , Rigidez Vascular/efeitos dos fármacos , Actinas/metabolismo , Animais , Aorta/metabolismo , Aorta/fisiologia , Células Cultivadas , Colágeno/metabolismo , Elasticidade , Feminino , Humanos , Artérias Mesentéricas/metabolismo , Artérias Mesentéricas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/fisiologia , Análise de Onda de Pulso
11.
Am J Physiol Heart Circ Physiol ; 323(4): H688-H701, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36018759

RESUMO

Inflammation and vascular insulin resistance are hallmarks of type 2 diabetes (T2D). However, several potential mechanisms causing abnormal endothelial insulin signaling in T2D need further investigation. Evidence indicates that the activity of ADAM17 (a disintegrin and metalloproteinase-17) and the presence of insulin receptor (IR) in plasma are increased in subjects with T2D. Accordingly, we hypothesized that in T2D, increased ADAM17 activity sheds the IR ectodomain from endothelial cells and impairs insulin-induced vasodilation. We used small visceral arteries isolated from a cross-sectional study of subjects with and without T2D undergoing bariatric surgery, human cultured endothelial cells, and recombinant proteins to test our hypothesis. Here, we demonstrate that arteries from subjects with T2D had increased ADAM17 expression, reduced presence of tissue inhibitor of metalloproteinase-3 (TIMP3), decreased extracellular IRα, and impaired insulin-induced vasodilation versus those from subjects without T2D. In vitro, active ADAM17 cleaved the ectodomain of the IRß subunit. Endothelial cells with ADAM17 overexpression or exposed to the protein kinase-C activator, PMA, had increased ADAM17 activity, decreased IRα presence on the cell surface, and increased IR shedding. Moreover, pharmacological inhibition of ADAM17 with TAPI-0 rescued PMA-induced IR shedding and insulin-signaling impairments in endothelial cells and insulin-stimulated vasodilation in human arteries. In aggregate, our findings suggest that ADAM17-mediated shedding of IR from the endothelial surface impairs insulin-mediated vasodilation. Thus, we propose that inhibition of ADAM17 sheddase activity should be considered a strategy to restore vascular insulin sensitivity in T2D.NEW & NOTEWORTHY To our knowledge, this is the first study to investigate the involvement of ADAM17 in causing impaired insulin-induced vasodilation in T2D. We provide evidence that ADAM17 activity is increased in the vasculature of patients with T2D and support the notion that ADAM17-mediated shedding of endothelial IRα ectodomains is a novel mechanism causing vascular insulin resistance. Our results highlight that targeting ADAM17 activity may be a potential therapeutic strategy to correct vascular insulin resistance in T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Proteína ADAM17/genética , Proteína ADAM17/metabolismo , Estudos Transversais , Diabetes Mellitus Tipo 2/metabolismo , Desintegrinas , Células Endoteliais/metabolismo , Humanos , Insulina/metabolismo , Receptor de Insulina/metabolismo , Proteínas Recombinantes/metabolismo , Inibidor Tecidual de Metaloproteinase-3/metabolismo
12.
J Nat Prod ; 85(3): 581-589, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35167289

RESUMO

Our ongoing efforts to explore the chemical space associated with marine cyanobacteria from coral reefs of Guam have yielded two new members of the anaenamide family of natural products, anaenamides C (3) and D (4). These compounds were isolated from a novel Hormoscilla sp. (VPG16-58). Our phylogenetic profiling (16S rDNA) of this cyanobacterium indicated that VPG16-58 is taxonomically distinct from the previously reported producer of the anaephenes, VPG16-59 (Hormoscilla sp.), and other previously documented species of the genus Hormoscilla. The planar structures of 3 and 4 were determined via spectroscopic methods, and absolute configurations of the α-hydroxy acids were assigned by enantioselective HPLC analysis. To address the requirement for sufficient material for testing, we first adapted our published linear synthetic approach for 1 and 2 to generate anaenoic acid (7), which served as a point for diversification, providing the primary amides 3 and 4 from synthetic intermediates 5 and 6, respectively. The compounds were then tested for effects on HCT116 colon cancer cell viability and in an ARE-luciferase reporter gene assay for Nrf2 modulation using HEK293 human embryonic kidney cells. Our findings indicate that, in contrast to cytotoxic methyl esters 1 and 2, the primary amides 3 and 4 activate the Nrf2 pathway at noncytotoxic concentrations. Overall, our data suggest that the anaenamide scaffold is tunable to produce differential biological outcomes.


Assuntos
Cianobactérias , Fator 2 Relacionado a NF-E2 , Amidas/farmacologia , Cianobactérias/química , Células HEK293 , Humanos , Filogenia
13.
Molecules ; 27(5)2022 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35268819

RESUMO

Dysidazirine carboxylic acid (1) was isolated from the lipophilic extract of a collection of the benthic marine cyanobacterium Caldora sp. from reefs near Fort Lauderdale, Florida. The planar structure of this new compound was determined by spectroscopic methods and comparisons between HRMS and NMR data with its reported methyl ester. The absolute configuration of the single chiral center was determined by the conversion of 1 to the methyl ester and the comparison of its specific rotation data with the two known methyl ester isomers, 2 and 3. Molecular sequencing with 16S rDNA indicated that this cyanobacterium differs from Caldora penicillata (Oscillatoriales) and represents a previously undocumented and novel Caldora species. Dysidazirine (2) showed weak cytotoxicity against HCT116 colorectal cancer cells (IC50 9.1 µM), while dysidazirine carboxylic acid (1) was non-cytotoxic. Similar cell viability patterns were observed in RAW264.7 cells with dysidazirine only (2), displaying cytotoxicity at the highest concentration tested (50 µM). The non-cytotoxic dysidazirine carboxylic acid (1) demonstrated anti-inflammatory activity in RAW264.7 cells stimulated with LPS. After 24 h, 1 inhibited the production of NO by almost 50% at 50 µM, without inducing cytotoxicity. Compound 1 rapidly decreased gene expression of the pro-inflammatory gene iNOS after 3 h post-LPS treatment and in a dose-dependent manner (IC50 ~1 µM); the downregulation of iNOS persisted at least until 12 h.


Assuntos
Azirinas , Ácidos Carboxílicos , Anti-Inflamatórios/farmacologia , Ácidos Carboxílicos/farmacologia , Florida , Humanos , Estrutura Molecular
14.
Oecologia ; 196(3): 619-631, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33630171

RESUMO

Forest cover and light availability comprise key factors for plant establishment in tropical forests. In the Brazilian Atlantic Forest (AF), Euterpe edulis (Areacaceae) is an endangered and keystone food resource contributing to forest functionality. We investigated the influence of forest loss and light availability on leaf traits and acclimatization of young individuals of E. edulis in AF fragments. We aimed to understand (i) how canopy openness and transmitted light are affected by forest cover at the landscape scale and the individual palm level; and (ii) how local and landscape features, combined and separately, affect key leaf traits widely known to be related to plant growth. The study was carried out in 15 forest fragments, ranging from 16 to 97% of surrounding forest cover. In each fragment, we sampled 10-20 individuals of E. edulis and analyzed nine leaf traits related to morphological, biochemical and chemical aspects. We also took hemispherical photographs to estimate canopy openness on the top of each E. edulis and also within fragment plots. We found that young plants predominantly occurred in more shaded environments. Additionally, E. edulis succeeded to acclimate in six of the nine traits analyzed, with most traits being affected by local and landscape features. It is likely that the lack of variation in traits related to protection against herbivory are limiting the species establishment in highly deforested landscapes. Our results provide novel evidence that both landscape and local contexts affect the leaf traits of E. edulis young plants leading to biochemical, chemical and morphological adjustments.


Assuntos
Euterpe , Florestas , Brasil , Ecossistema , Humanos , Folhas de Planta , Árvores
15.
An Acad Bras Cienc ; 93(suppl 1): e20201096, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076206

RESUMO

BINGO (BAO from Integrated Neutral Gas Observations) is a unique radio telescope designed to map the intensity of neutral hydrogen distribution at cosmological distances, making the first detection of Baryon Acoustic Oscillations (BAO) in the frequency band 980 MHz - 1260 MHz, corresponding to a redshift range 0.127 < z < 0.449. BAO is one of the most powerful probes of cosmological parameters and BINGO was designed to detect the BAO signal to a level that makes it possible to put new constraints on the equation of state of dark energy. The telescope will be built in Paraíba, Brazil and consists of two \thicksim 40m mirrors, a feedhorn array of 50 horns, and no moving parts, working as a drift-scan instrument. It will cover a 15 ^{\circ} ∘ declination strip centered at \sim \delta ∼ δ =-15 ^{\circ} ∘ , mapping \sim ∼ 5400 square degrees in the sky. The BINGO consortium is led by University of São Paulo with co-leadership at National Institute for Space Research and Campina Grande Federal University (Brazil). Telescope subsystems have already been fabricated and tested, and the dish and structure fabrication are expected to start in late 2020, as well as the road and terrain preparation.

16.
J Vasc Bras ; 20: e20200165, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34456984

RESUMO

Abdominal aortic aneurysm is an abnormal dilatation, while acute aortic dissection is a delamination of the tunica media, forming a false lumen. Tenascin-C is a glycoprotein that can be found in situations involving tissue damage. The objective of this article is to evaluate whether Tenascin-C assays could be of use for predicting prognosis in abdominal aortic aneurysms and acute aortic dissection. We conducted an integrative literature review, for which four articles were considered eligible. Two of these studies associated higher Tenascin-C levels with protective factors and lower risk of injury, whereas the other two correlated them with worse prognosis. Some authors believe that Tenascin-C could be a candidate biomarker, but these studies are still inconclusive with regard to its role in the clinical outcomes of patients with aneurysms.

17.
J Nat Prod ; 83(6): 2030-2035, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32463692

RESUMO

A new, cyclic carbonate eudesmane-type sesquiterpene, eudesmacarbonate (1), was isolated from marine filamentous cyanobacterial mats associated with apparent ingestion-related intoxications of captive bottlenose dolphins in the Florida Keys. Sequencing of 16S rDNA revealed that mats were composed of closely related Oscillatoriacean species including a previously undocumented species of Neolyngbya. The structure of 1 was elucidated by (+)-HRESIMS, 1D and 2D NMR, single-crystal X-ray diffraction, and vibrational circular dichroism data. Toxicity of 1 was assessed in the zebrafish embryo/larval model, and 1 was found to exhibit effects qualitatively similar to those observed for the known neurotoxin brevetoxin-2 and consistent with neurobehavioral impairment.


Assuntos
Cianobactérias/química , Síndromes Neurotóxicas/psicologia , Neurotoxinas/toxicidade , Sesquiterpenos de Eudesmano/toxicidade , Sesquiterpenos/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Embrião não Mamífero , Florida , Larva , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Difração de Raios X , Peixe-Zebra
18.
Surg Radiol Anat ; 42(5): 577-582, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31901966

RESUMO

PURPOSES: The main purpose of this study was to assess the measurements and shape of the sella turcica by using cone beam computed tomography (CBCT) and to associate the data to skeletal class II and class III patients, including correlations with gender, age and measurements of the anterior cranial base. MATERIAL AND METHODS: A trained examiner specialist in dental radiology selected and evaluated randomly 95 CBCT images of pre-orthognathic surgery patients, 60 (63.2%) being female and 35 (36.8%) male with age between 16 and 57 years. All images were evaluated to determine the size, shape and volume of the sella turcica. The anterior cranial base, represented by the S-N line (sella-nasion), was also measured. RESULTS: Of these 95 patients, 48 (50.5%) had class III facial skeletal pattern, whereas 47 (49.5%) had class II. No statistically significant differences were found between class II and class III patients in the measurements and shape of the sella turcica (P > 0.05). The diameter and volume of the sella turcica had higher values in female patients, whereas the measurements of the anterior cranial base were higher in males (P < 0.05). CONCLUSION: Therefore, one can conclude that measurements of the sella turcica are not reliable parameters to evaluate whether a class II or class III patient will or will not need orthognathic surgery.


Assuntos
Tomada de Decisão Clínica/métodos , Má Oclusão Classe III de Angle/cirurgia , Má Oclusão Classe II de Angle/cirurgia , Cirurgia Ortognática/métodos , Sela Túrcica/anatomia & histologia , Adolescente , Adulto , Fatores Etários , Cefalometria/métodos , Tomografia Computadorizada de Feixe Cônico , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios/métodos , Estudos Prospectivos , Reprodutibilidade dos Testes , Sela Túrcica/diagnóstico por imagem , Fatores Sexuais , Base do Crânio/anatomia & histologia , Base do Crânio/diagnóstico por imagem , Adulto Jovem
19.
Am J Physiol Heart Circ Physiol ; 317(7): H1-H12, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31002284

RESUMO

The purpose of the present study was to test the hypothesis that doxorubicin (DX) and cyclophosphamide (CY) adjuvant chemotherapy (CHT) acutely impairs neurovascular and hemodynamic responses in women with breast cancer. Sixteen women (age: 47.0 ± 2.0 yr; body mass index: 24.2 ± 1.5 kg/m) with stage II-III breast cancer and indication for adjuvant CHT underwent two experimental sessions, saline (SL) and CHT. In the CHT session, DX (60 mg/m2) and CY (600 mg/m2) were administered over 45 min. In the SL session, a matching SL volume was infused in 45 min. Muscle sympathetic nerve activity (MSNA) from peroneal nerve (microneurography), calf blood flow (CBF; plethysmography) and calf vascular conductance (CVC), heart rate (HR; electrocardiography), and beat-to-beat blood pressure (BP; finger plethysmography) were measured at rest before, during, and after each session. Venous blood samples (5 ml) were collected before and after both sessions for assessment of circulating endothelial microparticles (EMPs; flow cytometry), a surrogate marker for endothelial damage. MSNA and BP responses were increased (P < 0.001), whereas CBF and CVC responses were decreased (P < 0.001), during and after CHT session when compared with SL session. Interestingly, the vascular alterations were also observed at the molecular level through an increased EMP response to CHT (P = 0.03, CHT vs. SL session). No difference in HR response was observed (P > 0.05). Adjuvant CHT with DX and CY in patients treated for breast cancer increases sympathetic nerve activity and circulating EMP levels and, in addition, reduces muscle vascular conductance and elevates systemic BP. These responses may be early signs of CHT-induced cardiovascular alterations and may represent potential targets for preventive interventions. NEW & NOTEWORTHY It is known that chemotherapy regimens increase the risk of cardiovascular events in patients treated for cancer. Here, we identified that a single cycle of adjuvant chemotherapy with doxorubicin and cyclophosphamide in women treated for breast cancer dramatically increases sympathetic nerve activity and circulating endothelial microparticle levels, reduces the muscle vascular conductance, and elevates systemic blood pressure.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Ciclofosfamida/efeitos adversos , Doxorrubicina/efeitos adversos , Endotélio Vascular/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Adulto , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Micropartículas Derivadas de Células/efeitos dos fármacos , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/inervação , Nervo Fibular/fisiologia
20.
Trop Anim Health Prod ; 51(3): 697-702, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30414020

RESUMO

Bovine brucellosis poses a risk to human health and causes serious economic losses for the animal industry. This report describes the use of different diagnostic methods for the diagnosis of brucellosis in cattle affected by cervical bursitis from a slaughterhouse located in São Luís, Maranhão, Brazil. Serum samples from a total of 47 cattle with bursitis were collected and submitted to the Rose Bengal Test (RBT), and RBT-positive samples were further confirmed by the 2-mercaptoethanol (2-ME) assay. RBT indicated 85.1% (40/47) of positive samples, from which 78.7% (37/47) were confirmed by 2-ME. Immunohistochemistry detected Brucella spp. in 34.0% (16/47) of tissues with bursitis. PCR and/or bacterial isolation demonstrated that 63.8% (30/47) of samples were positive and morphologically compatible with Brucella sp. All colonies suggestive of Brucella sp. were confirmed by PCR. Isolates were further characterized by PCR Multiplex AMOS-ENHANCED, which indicated that the isolates corresponded to biovar 1, 2, 4 (43.33%). This study evidences an association between cervical bursitis and Brucella spp. infection in cattle, and that different biovars of Brucella circulate in bovine herds in Maranhão.


Assuntos
Brucella/isolamento & purificação , Brucelose Bovina/patologia , Bursite/veterinária , Animais , Brasil/epidemiologia , Brucelose Bovina/epidemiologia , Brucelose Bovina/microbiologia , Bursite/epidemiologia , Bursite/microbiologia , Bursite/patologia , Bovinos , Pescoço , Zoonoses
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