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1.
Physiol Rev ; 99(1): 235-309, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30354966

RESUMO

The thick ascending limb plays a key role in maintaining water and electrolyte balance. The importance of this segment in regulating blood pressure is evidenced by the effect of loop diuretics or local genetic defects on this parameter. Hormones and factors produced by thick ascending limbs have both autocrine and paracrine effects, which can extend prohypertensive signaling to other structures of the nephron. In this review, we discuss the role of the thick ascending limb in the development of hypertension, not as a sole participant, but one that works within the rich biological context of the renal medulla. We first provide an overview of the basic physiology of the segment and the anatomical considerations necessary to understand its relationship with other renal structures. We explore the physiopathological changes in thick ascending limbs occurring in both genetic and induced animal models of hypertension. We then discuss the racial differences and genetic defects that affect blood pressure in humans through changes in thick ascending limb transport rates. Throughout the text, we scrutinize methodologies and discuss the limitations of research techniques that, when overlooked, can lead investigators to make erroneous conclusions. Thus, in addition to advancing an understanding of the basic mechanisms of physiology, the ultimate goal of this work is to understand our research tools, to make better use of them, and to contextualize research data. Future advances in renal hypertension research will require not only collection of new experimental data, but also integration of our current knowledge.


Assuntos
Pressão Sanguínea/fisiologia , Extremidades/irrigação sanguínea , Hipertensão/metabolismo , Transporte de Íons/fisiologia , Sódio/metabolismo , Animais , Humanos , Equilíbrio Hidroeletrolítico/fisiologia
2.
Proc Natl Acad Sci U S A ; 120(33): e2303491120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549280

RESUMO

The formation of myelin, the fatty sheath that insulates nerve fibers, is critical for healthy brain function. A fundamental open question is what impact being born has on myelin growth. To address this, we evaluated a large (n = 300) cross-sectional sample of newborns from the Developing Human Connectome Project (dHCP). First, we developed software for the automated identification of 20 white matter bundles in individual newborns that is well suited for large samples. Next, we fit linear models that quantify how T1w/T2w (a myelin-sensitive imaging contrast) changes over time at each point along the bundles. We found faster growth of T1w/T2w along the lengths of all bundles before birth than right after birth. Further, in a separate longitudinal sample of preterm infants (N = 34), we found lower T1w/T2w than in full-term peers measured at the same age. By applying the linear models fit on the cross-section sample to the longitudinal sample of preterm infants, we find that their delay in T1w/T2w growth is well explained by the amount of time they spent developing in utero and ex utero. These results suggest that white matter myelinates faster in utero than ex utero. The reduced rate of myelin growth after birth, in turn, explains lower myelin content in individuals born preterm and could account for long-term cognitive, neurological, and developmental consequences of preterm birth. We hypothesize that closely matching the environment of infants born preterm to what they would have experienced in the womb may reduce delays in myelin growth and hence improve developmental outcomes.


Assuntos
Nascimento Prematuro , Substância Branca , Lactente , Feminino , Humanos , Recém-Nascido , Substância Branca/diagnóstico por imagem , Estudos Transversais , Imageamento por Ressonância Magnética/métodos , Recém-Nascido Prematuro , Bainha de Mielina , Encéfalo/diagnóstico por imagem
3.
Am J Physiol Renal Physiol ; 326(2): F249-F256, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38059297

RESUMO

Angiotensin II (ANG II) increases proximal tubule superoxide (O2-) production more in rats fed a 20% fructose normal-salt diet compared with rats fed a 20% glucose normal-salt diet. A 20% fructose high-salt diet (FHS) increases systolic blood pressure (SBP), whereas a 20% glucose high-salt diet (GHS) does not. However, it is unclear whether FHS enhances ANG II-induced oxidative stress in proximal tubules and whether this contributes to increases in blood pressure in this model. We hypothesized that FHS augments the ability of ANG II to stimulate O2- production by proximal tubules, and this contributes to fructose-induced salt-sensitive hypertension. We measured SBP in male Sprague-Dawley rats fed FHS and GHS and determined the effects of 3 mM tempol and 50 mg/kg losartan for 7 days. We then measured basal and ANG II-stimulated (3.7 × 10-8 M) O2- production by proximal tubule suspensions and the role of protein kinase C. FHS increased SBP by 27 ± 5 mmHg (n = 6, P < 0.006) but GHS did not. Rats fed FHS + tempol and GHS + tempol showed no significant increases in SBP. ANG II increased O2- production by 11 ± 1 relative light units/µg protein/s in proximal tubules from FHS-fed rats (n = 6, P < 0.05) but not in tubules from rats fed GHS. ANG II did not significantly stimulate O2- production by proximal tubules from rats fed FHS + tempol or FHS + losartan. The protein kinase C inhibitor Gö6976 blunted ANG II-stimulated O2- production. In conclusion, FHS enhances the sensitivity of proximal tubule O2- production to ANG II, and this contributes to fructose-induced salt-sensitive hypertension.NEW & NOTEWORTHY A diet containing amounts of fructose consumed by 17 million Americans causes salt-sensitive hypertension. Oxidative stress is an initiating cause of this model of fructose-induced salt-sensitive hypertension increasing blood pressure. This salt-sensitive hypertension is prevented by losartan and thus is angiotensin II (ANG II) dependent. Fructose-induced salt-sensitive hypertension depends on ANG II stimulating oxidative stress in the proximal tubule. A fructose/high-salt diet augments the ability of ANG II to stimulate proximal tubule O2- via protein kinase C.


Assuntos
Angiotensina II , Óxidos N-Cíclicos , Hipertensão , Marcadores de Spin , Humanos , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Superóxidos/metabolismo , Losartan/farmacologia , Frutose/farmacologia , Hipertensão/induzido quimicamente , Hipertensão/metabolismo , Cloreto de Sódio/metabolismo , Néfrons/metabolismo , Cloreto de Sódio na Dieta/metabolismo , Pressão Sanguínea , Proteína Quinase C/metabolismo , Glucose/farmacologia
4.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38474316

RESUMO

Single-cell RNA sequencing (scRNAseq) is a crucial tool in kidney research. These technologies cluster cells based on transcriptome similarity, irrespective of the anatomical location and order within the nephron. Thus, a transcriptome cluster may obscure the heterogeneity of the cell population within a nephron segment. Elevated dietary fructose leads to salt-sensitive hypertension, in part, through fructose reabsorption in the proximal tubule (PT). However, the organization of the four known fructose transporters in apical PTs (SGLT4, SGLT5, GLUT5, and NaGLT1) remains poorly understood. We hypothesized that cells within each subsegment of the proximal tubule exhibit complex, heterogeneous fructose transporter expression patterns. To test this hypothesis, we analyzed rat kidney transcriptomes and proteomes from publicly available scRNAseq and tubule microdissection databases. We found that microdissected PT-S1 segments consist of 81% ± 12% cells with scRNAseq-derived transcriptional characteristics of S1, whereas PT-S2 express a mixture of 18% ± 9% S1, 58% ± 8% S2, and 19% ± 5% S3 transcripts, and PT-S3 consists of 75% ± 9% S3 transcripts. The expression of all four fructose transporters was detectable in all three PT segments, but key fructose transporters SGLT5 and GLUT5 progressively increased from S1 to S3, and both were significantly upregulated in S3 vs. S1/S2 (Slc5a10: 1.9 log2FC, p < 1 × 10-299; Scl2a5: 1.4 log2FC, p < 4 × 10-105). A similar distribution was found in human kidneys. These data suggest that S3 is the primary site of fructose reabsorption in both humans and rats. Finally, because of the multiple scRNAseq transcriptional phenotypes found in each segment, our findings also imply that anatomical labels applied to scRNAseq clusters may be misleading.


Assuntos
Frutose , Transcriptoma , Humanos , Ratos , Animais , Frutose/metabolismo , Néfrons/metabolismo , Rim/metabolismo , Túbulos Renais Proximais/metabolismo , Proteínas de Membrana Transportadoras/metabolismo
5.
Exp Dermatol ; 32(5): 660-670, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36645024

RESUMO

Atopic dermatitis (AD) is a Th2-type inflammatory disease characterized by an alteration of epidermal barrier following the release of IL-4 and IL-13. These cytokines activate type II IL-4Rα/IL-13Rα1 receptors in the keratinocyte. Whilst IL-2Rγ, that forms type I receptor for IL-4, is only expressed in haematopoietic cells, recent studies suggest its induction in keratinocytes, which questions about its role. We studied expression of IL-2Rγ in keratinocytes and its role in alteration of keratinocyte function and epidermal barrier. IL-2Rγ expression in keratinocytes was studied using both reconstructed human epidermis (RHE) exposed to IL-4/IL-13 and AD skin. IL-2Rγ induction by type II receptor has been analyzed using JAK inhibitors and RHE knockout (KO) for IL13RA1. IL-2Rγ function was investigated in RHE KO for IL2RG. In RHE, IL-4/IL-13 induce expression of IL-2Rγ at the mRNA and protein levels. Its mRNA expression is also visualized in keratinocytes of lesional AD skin. IL-2Rγ expression is low in RHE treated with JAK inhibitors and absent in RHE KO for IL13RA1. Exposure to IL-4/IL-13 alters epidermal barrier, but this alteration is absent in RHE KO for IL2RG. A more important induction of IL-13Rα2 is reported in RHE KO for IL2RG than in not edited RHE. These results demonstrate IL-2Rγ induction in keratinocytes through activation of type II receptor. IL-2Rγ is involved in the alteration of the epidermal barrier and in the regulation of IL-13Rα2 expression. Observation of IL-2Rγ expression by keratinocytes inside AD lesional skin suggests a role for this receptor subunit in the disease.


Assuntos
Dermatite Atópica , Subunidade gama Comum de Receptores de Interleucina , Humanos , Células Cultivadas , Dermatite Atópica/metabolismo , Epiderme/metabolismo , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Inibidores de Janus Quinases , Queratinócitos/metabolismo , RNA Mensageiro/metabolismo , Subunidade gama Comum de Receptores de Interleucina/metabolismo
6.
Pediatr Nephrol ; 38(4): 1115-1126, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35943576

RESUMO

BACKGROUND: Minimal change disease (MCD) is the major cause of childhood idiopathic nephrotic syndrome, which is characterized by massive proteinuria and debilitating edema. Proteinuria in MCD is typically rapidly reversible with corticosteroid therapy, but relapses are common, and children often have many adverse events from the repeated courses of immunosuppressive therapy. The pathobiology of MCD remains poorly understood. Prior clinical observations suggest that abnormal T-cell function may play a central role in MCD pathogenesis. Based on these observations, we hypothesized that T-cell responses to specific exposures or antigens lead to a clonal expansion of T-cell subsets, a restriction in the T-cell repertoire, and an elaboration of specific circulating factors that trigger disease onset and relapses. METHODS: To test these hypotheses, we sequenced T-cell receptors in fourteen MCD, four focal segmental glomerulosclerosis (FSGS), and four membranous nephropathy (MN) patients with clinical data and blood samples drawn during active disease and during remission collected by the Nephrotic Syndrome Study Network (NEPTUNE). We calculated several T-cell receptor diversity metrics to assess possible differences between active disease and remission states in paired samples. RESULTS: Median productive clonality did not differ between MCD active disease (0.0083; range: 0.0042, 0.0397) and remission (0.0088; range: 0.0038, 0.0369). We did not identify dominant clonotypes in MCD active disease, and few clonotypes were shared with FSGS and MN patients. CONCLUSIONS: While these data do not support an obvious role of the adaptive immune system T-cells in MCD pathogenesis, further study is warranted given the limited sample size. A higher resolution version of the Graphical abstract is available as Supplementary information.


Assuntos
Glomerulonefrite Membranosa , Glomerulosclerose Segmentar e Focal , Nefrose Lipoide , Síndrome Nefrótica , Criança , Humanos , Nefrose Lipoide/tratamento farmacológico , Glomerulosclerose Segmentar e Focal/complicações , Netuno , Síndrome Nefrótica/tratamento farmacológico , Proteinúria/etiologia , Glomerulonefrite Membranosa/complicações , Receptores de Antígenos de Linfócitos T/uso terapêutico , Recidiva
7.
Environ Res ; 228: 115860, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37030405

RESUMO

The immobilization of TiO2-SiO2 (TSO) materials on seed mats stands as a practical way to help the germination and early growth of tomato plants (Solanum Lycopersicum). Mesoporous materials are functionalized with triethanolamine (TEA) and loaded with the biocide molecule of carvacrol (CAR). The effect of CAR on the parameters of germination percentage, germination time, root, shoot length, and chlorophyll content of seeds and/or tomato seedlings are investigated. The germination experiments were carried out using seed mats coated with the TSO materials, also TSO powdered materials were put directly on the tomato seeds to study their effect on germination. Direct deposition of TSO composites achieved the complete germination and longer shoots due to the cooperative interactions among nanomaterials, carvacrol, and the tomato seed. However, the handling of the seeds and the detrimental effect of powder in the germination system made difficult the application with agricultural purposes. The plastic seed mats provide a practical system with lower germination, but more homogenous growth of root/shoot is possible. Surprisingly, in this methodology the carvacrol presents a detrimental effect on germination due to less interaction with the seeds. The handling of seeds and recover of the nanomaterials and its reuse are advantages of the plastic seed mats, which together with less wastage of seeds suggest a potential use in agriculture. The as-synthetized TSO NPs, together with the functionalization of triethanolamine and carvacrol used to promote the health germination of the seeds, allows the control of the time for seed germination, germination %, and length for the root/shoot of seed tomato germination. The immobilization of mesoporous materials results in an alternative to help the germination and early growth of agricultural plants searching to avoid the lixiviation of nanomaterials to the environment.


Assuntos
Germinação , Solanum lycopersicum , Dióxido de Silício , Sementes
8.
J Digit Imaging ; 36(5): 2259-2277, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37468696

RESUMO

Peri-implantitis can cause marginal bone remodeling around implants. The aim is to develop an automatic image processing approach based on two artificial intelligence (AI) techniques in intraoral (periapical and bitewing) radiographs to assist dentists in determining bone loss. The first is a deep learning (DL) object-detector (YOLOv3) to roughly identify (no exact localization is required) two objects: prosthesis (crown) and implant (screw). The second is an image understanding-based (IU) process to fine-tune lines on screw edges and to identify significant points (intensity bone changes, intersections between screw and crown). Distances between these points are used to compute bone loss. A total of 2920 radiographs were used for training (50%) and testing (50%) the DL process. The mAP@0.5 metric is used for performance evaluation of DL considering periapical/bitewing and screws/crowns in upper and lower jaws, with scores ranging from 0.537 to 0.898 (sufficient because DL only needs an approximation). The IU performance is assessed with 50% of the testing radiographs through the t test statistical method, obtaining p values of 0.0106 (line fitting) and 0.0213 (significant point detection). The IU performance is satisfactory, as these values are in accordance with the statistical average/standard deviation in pixels for line fitting (2.75/1.01) and for significant point detection (2.63/1.28) according to the expert criteria of dentists, who establish the ground-truth lines and significant points. In conclusion, AI methods have good prospects for automatic bone loss detection in intraoral radiographs to assist dental specialists in diagnosing peri-implantitis.


Assuntos
Perda do Osso Alveolar , Peri-Implantite , Dente , Humanos , Inteligência Artificial , Próteses e Implantes
9.
Int J Mol Sci ; 24(6)2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36982465

RESUMO

Patients admitted for acute coronary syndrome (ACS) usually have high cardiovascular risk scores with low levels of high-density lipoprotein cholesterol (HDL-C) and high low-density lipoprotein cholesterol (LDL-C) levels. Here, we investigated the role of lipoprotein functionality as well as particle number and size in patients with a first-onset ACS with on-target LDL-C levels. Ninety-seven patients with chest pain and first-onset ACS with LDL-C levels of 100 ± 4 mg/dL and non-HDL-C levels of 128 ± 4.0 mg/dL were included in the study. Patients were categorized as ACS and non-ACS after all diagnostic tests were performed (electrocardiogram, echocardiogram, troponin levels and angiography) on admission. HDL-C and LDL-C functionality and particle number/size by nuclear magnetic resonance (NMR) were blindly investigated. A group of matched healthy volunteers (n = 31) was included as a reference for these novel laboratory variables. LDL susceptibility to oxidation was higher and HDL-antioxidant capacity lower in the ACS patients than in the non-ACS individuals. ACS patients had lower HDL-C and Apolipoprotein A-I levels than non-ACS patients despite the same prevalence of classical cardiovascular risk factors. Cholesterol efflux potential was impaired only in the ACS patients. ACS-STEMI (Acute Coronary Syndrome-ST-segment-elevation myocardial infarction) patients, had a larger HDL particle diameter than non-ACS individuals (8.4 ± 0.02 vs. 8.3 ± 0.02 and, ANOVA test, p = 0.004). In conclusion, patients admitted for chest pain with a first-onset ACS and on-target lipid levels had impaired lipoprotein functionality and NMR measured larger HDL particles. This study shows the relevance of HDL functionality rather than HDL-C concentration in ACS patients.


Assuntos
Síndrome Coronariana Aguda , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Síndrome Coronariana Aguda/diagnóstico , LDL-Colesterol , Colesterol , HDL-Colesterol , Lipoproteínas , Dor no Peito
10.
J Environ Sci (China) ; 126: 575-589, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36503783

RESUMO

We present the structural, morphological and photocatalytic properties of stretchable composites made with carbon nanotubes (CNTs), silicon rubber and Ni@TiO2:W nanoparticles (TiWNi NPs) with average size of 37 ± 2 nm. Microscopy images showed that the TiWNi NPs decorated the surface of the CNT fibers, which are oriented in a preferential direction. TiWNi NPs presented a mixture of anatase/rutile phases with cubic structure. The performance of the TiWNi powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible light. The results revealed that the maximum DCF degradation percentages were 34.6%, 91.9%, 97.1%, 98.5% and 100% for the CNT composite (stretched at 0%), TiWNi powders, CNT + TiWNi (stretched at 0%), CNT + TiWNi (stretched at 50%) and CNT + TiWNi (stretched at 100%), respectively. Thus, stretching the CNT + TiWNi composites was a good strategy to enhance the DCF degradation percentage from 97.1% to 100%, since stretching created additional defects (oxygen vacancies) that acted as electron sink, delaying the electron-hole recombination, and favors the DCF degradation. Raman/absorbance measurements confirmed the presence of such defects. Moreover, the reactive oxygen species (ROS) were determined by the scavenger's experiments and found that the main ROS were the ·OH and O2- radicals, which attacked the DCF molecules, causing their degradation. The results of this investigation confirmed that the stretchable CNT/TiWNi-based composites are a viable alternative to remove pharmaceutical contaminants from water and can be manually separated from the decontaminated water, which is unviable using photocatalytic powders.


Assuntos
Água Potável , Nanotubos de Carbono , Diclofenaco , Elétrons , Oxigênio
11.
Eur J Clin Invest ; 52(4): e13709, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34757635

RESUMO

BACKGROUND: Atrial fibrillation (AF) increases the risk of thromboembolism. We investigate the efficacy and safety of oral anticoagulation (OAC) therapy and explored the number needed to treat for net effect (NNTnet) of OAC in the Spanish cohort of the EURObservational Research Programme-AF (EORP-AF) Long-term General Registry. METHODS: The EORP-AF General Registry is a prospective, multicentre registry conducted in ESC countries, including consecutive AF patients. For the present analysis, we used the Spanish cohort, and the primary outcome was any thromboembolism (TE)/acute coronary syndrome (ACS)/cardiovascular death during the first year of follow-up. RESULTS: 729 AF patients were included (57.1% male, median age 75 [IQR 67-81] years, median CHA2 DS2 -VASc and HAS-BLED of 3 [IQR 2-5] and 2 [IQR 1-2], respectively). 548 (75.2%) patients received OAC alone (318 [43.6%] on VKAs and 230 [31.6%] on DOACs). After 1 year, the use of OAC alone showed lower rates of any TE/ACS/cardiovascular death (3.0%/year; p < 0.001) compared to other regimens, and non-use of OAC alone (HR 4.18, 95% CI 2.12-8.27) was independently associated with any TE/ACS/cardiovascular death. Balancing the effects of treatment, the NNTnet to provide an overall benefit of OAC therapy was 24. The proportion of patients on OAC increased at 1 year (87% to 88.1%), particularly on DOACs (33.6% to 39.9%) (p = 0.015), with low discontinuation rates. CONCLUSIONS: In this contemporary cohort of AF patients, OAC therapy was associated with better clinical outcomes at 1 year and positive NNTnet. OAC use slightly increased during the follow-up, with low discontinuation rates and higher prescription of DOACs.


Assuntos
Fibrinolíticos/administração & dosagem , Tromboembolia/prevenção & controle , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/complicações , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos Prospectivos , Sistema de Registros , Espanha , Tromboembolia/etiologia , Fatores de Tempo , Resultado do Tratamento
12.
Vet Pathol ; 59(6): 950-959, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35787065

RESUMO

Pithomycotoxicosis (facial eczema) is a seasonal hepatogenous photosensitization of sheep caused by the ingestion of sporidesmin contained in the spores of the fungus Pithomyces chartarum. We describe 4 cases of obstructive rhinopathy associated with chronic pithomycotoxicosis naturally occurring in the north of Spain. Sheep were 5 to 7 years old and Latxa breed. A detailed clinical study was conducted together with computerized tomography examination and completed by necropsy and histopathology. All sheep developed a permanent narrowing of the nasal lumen close to the nostrils causing inspiratory dyspnea and snoring. Computerized tomography demonstrated a significant increase of soft tissue in the rostral nasal cavity. Elevated gamma-glutamyl transferase, alanine aminotransferase, and lipase were noted on serum biochemistry. At necropsy, liver atrophy and fibrosis associated with chronic pithomycotoxicosis was identified in 3 of the sheep. All sheep had whitish elevations and rough surfaces on the alar folds and areas adjacent to the nasal surfaces. Histopathologic assessments, which included histochemical and immunohistochemical techniques, of the nasal lesions identified moderate to severe arteriosclerosis in 21.5% to 61.9% of the small arteries evaluated with surrounding fibrosis and edema. No changes associated with hypersensitivity reactions were found. These lesions were similar to the ones described in blood vessels of the liver in chronic pithomycotoxicosis and in our cases. The results of this study suggest a direct action of the sporidesmin on the rostral nasal cavity. Further studies are needed to analyze the impact of the sporidesmin on the sheep nasal mucosa.


Assuntos
Doenças dos Ovinos , Esporidesminas , Alanina Transaminase , Animais , Fibrose , Lipase , Ovinos , Doenças dos Ovinos/etiologia
13.
Am J Physiol Renal Physiol ; 321(3): F369-F377, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34308669

RESUMO

Dahl salt-sensitive (SS) rat kidneys produce less nitric oxide (NO) than those of salt-resistant (SR) rats. Thick ascending limb (TAL) NO synthase 3 (NOS3) is a major source of renal NO, and luminal flow enhances its activity. We hypothesized that flow-induced NO is reduced in TALs from SS rats primarily due to NOS uncoupling and diminished NOS3 expression rather than scavenging. Rats were fed normal-salt (NS) or high-salt (HS) diets. We measured flow-induced NO and superoxide in perfused TALs and performed Western blots of renal outer medullas. For rats on NS, flow-induced NO was 35 ± 6 arbitrary units (AU)/min in TALs from SR rats but only 11 ± 2 AU/min in TALs from SS (P < 0.008). The superoxide scavenger tempol decreased the difference in flow-induced NO between strains by about 36% (P < 0.020). The NOS inhibitor N-nitro-l-arginine methyl ester (l-NAME) decreased flow-induced superoxide by 36 ± 8% in TALs from SS rats (P < 0.02) but had no effect in TALs from SR rats. NOS3 expression was not different between strains on NS. For rats on HS, the difference in flow-induced NO between strains was enhanced (SR rats: 44 ± 10 vs. SS: 9 ± 2 AU/min, P < 0.005). Tempol decreased the difference in flow-induced NO between strains by about 37% (P < 0.012). l-NAME did not significantly reduce flow-induced superoxide in either strain. HS increased NOS3 expression in TALs from SR rats but not in TALs from SS rats (P < 0.003). We conclude that 1) on NS, flow-induced NO is diminished in TALs from SS rats mainly due to NOS3 uncoupling such that it produces superoxide and 2) on HS, the difference is enhanced due to failure of TALs from SS rats to increase NOS3 expression.NEW & NOTEWORTHY The Dahl rat has been used extensively to study the causes and effects of salt-sensitive hypertension. Our study suggests that more complex processes other than simple scavenging of nitric oxide (NO) by superoxide lead to less NO production in thick ascending limbs of the Dahl salt-sensitive rat. The predominant mechanism involved depends on dietary salt. Impaired flow-induced NO production in thick ascending limbs most likely contributes to the Na+ retention associated with salt-sensitive hypertension.


Assuntos
Alça do Néfron/metabolismo , Óxido Nítrico/metabolismo , Cloreto de Sódio na Dieta/metabolismo , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Hipertensão/fisiopatologia , Masculino , Ratos Endogâmicos Dahl , Cloreto de Sódio/metabolismo , Superóxidos/metabolismo
14.
Eur J Clin Invest ; 51(4): e13431, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33065765

RESUMO

BACKGROUND: Atrial fibrillation (AF) and peripheral artery disease (PAD) are common conditions that increase cardiovascular risk. We determined the association between PAD and prognosis in a cohort of real-world patients receiving oral anticoagulant therapy for nonvalvular AF. METHODS: We prospectively included 1956 patients (mean age 73.8 ± 9.5 years, 44.0% women) receiving oral anticoagulant therapy for AF. Clinical characteristics were collected at baseline. Patients were followed for a period of 3 years. Survival analysis and multivariable regression analyses were performed to assess variables related to death, stroke, bleeding, myocardial infarction and major adverse cardiovascular events (MACE). RESULTS: Patients with PAD (n = 118; 6%) exhibited higher rates of cardiovascular risk factors and cardiovascular diseases. After 3 years of follow-up, there were a total of 255 deaths (no PAD 233, vs PAD 22), 45 strokes (43 vs 2), 146 major bleedings (136 vs 10) and 168 MACE (148 vs 20). On univariate analysis, there was a higher risk of cardiovascular mortality (2.02%/year no PAD vs 4.08%/year PAD, P = .02), myocardial infarction (0.99%/year no PAD vs 2.43%/year PAD, P = .02) and MACE (3.18%/year no PAD vs 6.99%/year PAD, P < .01). There was no statistically significant association with these events after multivariable adjustment. CONCLUSIONS: In a large cohort of anticoagulated patients with AF, the presence of PAD represents a higher risk subgroup and is associated with worse crude outcomes. The exact contribution of the PAD independently of other cardiovascular diseases or risk factors requires further investigation.


Assuntos
Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Doença Arterial Periférica/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Doenças Cardiovasculares/mortalidade , Comorbidade , Feminino , Hemorragia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Sistema de Registros , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia
15.
Catheter Cardiovasc Interv ; 98(3): E342-E350, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33829625

RESUMO

BACKGROUND: Routine manual thrombectomy (MT) is not recommended in primary percutaneous coronary intervention (P-PCI) but it is performed in many procedures. The objective of our study was validating the DDTA score, designed for selecting patients who benefit most from MT. METHODS: Observational and multicenter study of all consecutive patients undergoing P-PCI in five institutions. Results were compared with the design cohort and the performance of the DDTA was analyzed in all patients. Primary end-point of the analyses was TIMI 3 after MT; secondary endpoints were final TIMI 3, no-reflow incidence, in-hospital mortality and in-hospital major cardiovascular events (MACE). In-hospital prognosis was assessed by the Zwolle risk score. RESULTS: Three hundred forty patients were included in the validation cohort and no differences were observed as compared to the design cohort (618 patients) except for lower use of MT and higher IIb/IIIa inhibitors or drug-eluting stents. The probability of TIMI 3 after MT decreased as delay to P-PCI was higher. If DDTA score, MT was associated to TIMI 3 after MT (OR: 4.11) and final TIMI 3 (OR: 2.44). There was a linear and continuous relationship between DDTA score and all endpoints. DDTA score ≥ 4 was independently associated to lower no-reflow, in-hospital MACE or mortality. The lowest incidence of in-hospital mortality or MACE was in patients who had DDTA score ≥ 4 and Zwolle risk score 0-3. CONCLUSIONS: MT is associated to higher rate of final TIMI3 in patients with the DDTA score ≥ 4. Patients with DDTA score ≥ 4 had lower no-reflow and in-hospital complications.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Ácido Edético/análogos & derivados , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Trombectomia , Resultado do Tratamento
16.
J Cardiovasc Pharmacol ; 77(2): 164-169, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33351537

RESUMO

BACKGROUND: Clinical trials have assessed the effect of direct oral antagonists (DOACs) in patients with atrial fibrillation (AF) after percutaneous coronary interventions (PCI). Studies were designed to test the effect on bleeding incidence, but concerns related to safety on ischemic events remain. METHODS: We performed a meta-analysis with currently available studies involving DOACs versus Vitamin-K antagonist (VKA) in patients with AF after PCI. The primary endpoint was the incidence of cardiac ischemic events, including myocardial infarction and stent thrombosis. Secondary endpoints were the incidence of stroke, all-cause mortality, and major bleeding. RESULTS: Eleven thousand twenty-three patients were included in the analysis: 5510 receiving DOACs and 5513 VKA. A total of 190 cases of myocardial infarction were registered in patients treated with DOACs and 177 in patients on VKA, and no statistical difference was noted [relative risk (RR): 1.07 95% confidence interval (CI) 0.88-1.31]. The incidence of stent thrombosis was very low with no differences between both treatment strategies (RR: 1.14 95% CI 0.76-1.71). The incidence of cardiac ischemic events was the same in patients receiving DOACs or VKA (HR 1.09 95% CI 0.91-1.30). No differences were observed in the incidence of stroke (RR: 0.86 95% CI 0.61-1.23) or mortality (RR: 1.09, 95% CI 0.90-1.31). Treatment with DOACs was associated with 34% reduction in major bleeding (RR: 0.66, 95% CI 0.54-0.81). CONCLUSIONS: Treatment with DOACs in patients with AF after a PCI do not increase the risk of cardiac ischemic events, stroke, or death and reduce the incidence of major bleeding by 34% as compared with VKA.


Assuntos
Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Inibidores do Fator Xa/uso terapêutico , Isquemia Miocárdica/terapia , Intervenção Coronária Percutânea , Vitamina K/antagonistas & inibidores , Anticoagulantes/efeitos adversos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/mortalidade , Trombose Coronária/mortalidade , Inibidores do Fator Xa/efeitos adversos , Hemorragia/induzido quimicamente , Humanos , Incidência , Infarto do Miocárdio/mortalidade , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/mortalidade , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Medição de Risco , Fatores de Risco , Stents , Acidente Vascular Cerebral/mortalidade , Fatores de Tempo , Resultado do Tratamento
17.
Sensors (Basel) ; 22(1)2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35009833

RESUMO

Atrial substrate modification after pulmonary vein isolation (PVI) of paroxysmal atrial fibrillation (pAF) can be assessed non-invasively by analyzing P-wave duration in the electrocardiogram (ECG). However, whether right (RA) and left atrium (LA) contribute equally to this phenomenon remains unknown. The present study splits fundamental P-wave features to investigate the different RA and LA contributions to P-wave duration. Recordings of 29 pAF patients undergoing first-ever PVI were acquired before and after PVI. P-wave features were calculated: P-wave duration (PWD), duration of the first (PWDon-peak) and second (PWDpeak-off) P-wave halves, estimating RA and LA conduction, respectively. P-wave onset (PWon-R) or offset (PWoff-R) to R-peak interval, measuring combined atrial/atrioventricular and single atrioventricular conduction, respectively. Heart-rate fluctuation was corrected by scaling. Pre- and post-PVI results were compared with Mann-Whitney U-test. PWD was correlated with the remaining features. Only PWD (non-scaling: Δ=-9.84%, p=0.0085, scaling: Δ=-17.96%, p=0.0442) and PWDpeak-off (non-scaling: Δ=-22.03%, p=0.0250, scaling: Δ=-27.77%, p=0.0268) were decreased. Correlation of all features with PWD was significant before/after PVI (p<0.0001), showing the highest value between PWD and PWon-R (ρmax=0.855). PWD correlated more with PWDon-peak (ρ= 0.540-0.805) than PWDpeak-off (ρ= 0.419-0.710). PWD shortening after PVI of pAF stems mainly from the second half of the P-wave. Therefore, noninvasive estimation of LA conduction time is critical for the study of atrial substrate modification after PVI and should be addressed by splitting the P-wave in order to achieve improved estimations.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Átrios do Coração , Humanos , Veias Pulmonares/cirurgia , Recidiva , Resultado do Tratamento
18.
J Environ Manage ; 284: 111983, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33529884

RESUMO

Lignocellulosic biomass has become an important sustainable resource for fuels, chemicals and energy. It is an attractive source for alternative fuels and green chemicals because it is non-edible and widely available in the planet in huge volumes. The use of biomass as starting material to produce fuels and chemicals leads to closed carbon cycle and promotes circular economy. Although there are many thermo-chemical methods such as pyrolysis, liquefaction and gasification close at hand for processing lignocellulosic biomass and transforming the derived compounds into valuable chemicals and fuels, the photocatalytic method is more advantageous as it utilizes light and ambient conditions for reforming the said compounds. Appraisal of recent literature indicates a variety of photocatalytic systems involving different catalysts, reactors and conditions studied for this purpose. This article reviews the recent developments on the photocatalytic oxidation of biomass and its derivatives into value-added chemicals. The nature of the biomass and derived molecules, nature of the photocatalysts, efficiency of the photocatalysts in terms of conversion and selectivity, influence of reaction conditions and light sources, effect of additives and mechanistic pathways are discussed. Importance has been given also to discuss the complementary technologies that could be coupled with photocatalysis for better conversion of biomass and biomass-derived molecules to value-added chemicals. A summary of these aspects, conclusions and future prospects are given in the end.


Assuntos
Lignina , Biomassa , Catálise , Lignina/metabolismo , Oxirredução
19.
Am J Physiol Renal Physiol ; 318(1): F183-F192, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31760771

RESUMO

Angiotensin II exacerbates oxidative stress in part by increasing superoxide (O2-) production by many renal tissues. However, whether it does so in proximal tubules and the source of O2- in this segment are unknown. Dietary fructose enhances the stimulatory effect of angiotensin II on proximal tubule Na+ reabsorption, but whether this is true for oxidative stress is unknown. We hypothesized that angiotensin II causes proximal nephron oxidative stress in part by stimulating NADPH oxidase (NOX)4-dependent O2- production and decreasing the amount of the antioxidant glutathione, and this is exacerbated by dietary fructose. We measured basal and angiotensin II-stimulated O2- production with and without inhibitors, NOX1 and NOX4 expression, and total and reduced glutathione (GSH) in proximal tubules from rats drinking either tap water (control) or 20% fructose. Angiotensin II (10 nM) increased O2- production by 113 ± 42 relative light units·mg protein-1·s-1 in controls and 401 ± 74 relative light units·mg protein-1·s-1 with 20% fructose (n = 11 for each group, P < 0.05 vs. control). Apocynin and the Nox1/4 inhibitor GKT136901 prevented angiotensin II-induced increases in both groups. NOX4 expression was not different between groups. NOX1 expression was undetectable. Angiotensin II decreased GSH by 1.8 ± 0.8 nmol/mg protein in controls and by 4.2 ± 0.9 nmol/mg protein with 20% fructose (n = 18 for each group, P < 0.047 vs. control). We conclude that 1) angiotensin II causes oxidative stress in proximal tubules by increasing O2- production by NOX4 and decreasing GSH and 2) dietary fructose enhances the ability of angiotensin II to stimulate O2- and diminish GSH, thereby exacerbating oxidative stress in this segment.


Assuntos
Angiotensina II/farmacologia , Glutationa/metabolismo , Túbulos Renais Proximais/efeitos dos fármacos , Superóxidos/metabolismo , Acetofenonas/farmacologia , Animais , Antioxidantes/farmacologia , Açúcares da Dieta , Frutose , Túbulos Renais Proximais/metabolismo , Masculino , NADPH Oxidases/metabolismo , Néfrons/efeitos dos fármacos , Néfrons/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pirazóis/farmacologia , Piridonas/farmacologia , Ratos , Ratos Sprague-Dawley
20.
Sensors (Basel) ; 20(17)2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32899314

RESUMO

The digital world is spreading to all sectors of the economy, and Industry 4.0, with the digital twin, is a reality in the building sector. Energy reduction and decarbonization in buildings are urgently required. Models are the base for prediction and preparedness for uncertainty. Building energy models have been a growing field for a long time. This paper proposes a novel calibration methodology for a building energy model based on two pillars: simplicity, because there is an important reduction in the number of parameters (four) to be adjusted, and cost-effectiveness, because the methodology minimizes the number of sensors provided to perform the process by 47.5%. The new methodology was validated empirically and comparatively based on a previous work carried out in Annex 58 of the International Energy Agency (IEA). The use of a tested and structured experiment adds value to the results obtained.

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