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Macrophages infiltrating tumour tissues or residing in the microenvironment of solid tumours are known as tumour-associated macrophages (TAMs). These specialized immune cells play crucial roles in tumour growth, angiogenesis, immune regulation, metastasis, and chemoresistance. TAMs encompass various subpopulations, primarily classified into M1 and M2 subtypes based on their differentiation and activities. M1 macrophages, characterized by a pro-inflammatory phenotype, exert anti-tumoural effects, while M2 macrophages, with an anti-inflammatory phenotype, function as protumoural regulators. These highly versatile cells respond to stimuli from tumour cells and other constituents within the tumour microenvironment (TME), such as growth factors, cytokines, chemokines, and enzymes. These stimuli induce their polarization towards one phenotype or another, leading to complex interactions with TME components and influencing both pro-tumour and anti-tumour processes.This review comprehensively and deeply covers the literature on macrophages, their origin and function as well as the intricate interplay between macrophages and the TME, influencing the dual nature of TAMs in promoting both pro- and anti-tumour processes. Moreover, the review delves into the primary pathways implicated in macrophage polarization, examining the diverse stimuli that regulate this process. These stimuli play a crucial role in shaping the phenotype and functions of macrophages. In addition, the advantages and limitations of current macrophage based clinical interventions are reviewed, including enhancing TAM phagocytosis, inducing TAM exhaustion, inhibiting TAM recruitment, and polarizing TAMs towards an M1-like phenotype. In conclusion, while the treatment strategies targeting macrophages in precision medicine show promise, overcoming several obstacles is still necessary to achieve an accessible and efficient immunotherapy.
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Imunoterapia , Neoplasias , Microambiente Tumoral , Macrófagos Associados a Tumor , Humanos , Microambiente Tumoral/imunologia , Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/patologia , Macrófagos Associados a Tumor/imunologia , Medicina de Precisão , Macrófagos/imunologia , AnimaisRESUMO
Neuropathic pain, defined as the most terrible of all tortures, which a nerve wound may inflict, is a common chronic painful condition caused by gradual damage or dysfunction of the somatosensory nervous system. As with many chronic diseases, neuropathic pain has a profound economic and emotional impact worldwide and represents a major public health issue from a treatment standpoint. This condition involves multiple sensory symptoms including impaired transmission and perception of noxious stimuli, burning, shooting, spontaneous pain, mechanical or thermal allodynia and hyperalgesia. Current pharmacological options for the treatment of neuropathic pain are limited, ineffective and have unacceptable side effects. In this framework, a deeper understanding of the pathophysiology and molecular mechanisms associated with neuropathic pain is key to the development of promising new therapeutical approaches. For this purpose, a plethora of experimental models that mimic common clinical features of human neuropathic pain have been characterized in rodents, with the spinal nerve ligation (SNL) model being one of the most widely used. In this chapter, we provide a detailed surgical procedure of the SNL model used to induce neuropathic pain in rats and mice. We further describe the behavioral approaches used for stimulus-evoked and spontaneous pain assessment in rodents. Finally, we demonstrate that our SNL model induces multiple pain behaviors in rats and mice.
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Modelos Animais de Doenças , Neuralgia , Nervos Espinhais , Animais , Neuralgia/patologia , Neuralgia/fisiopatologia , Neuralgia/etiologia , Ligadura/métodos , Ligadura/efeitos adversos , Ratos , Camundongos , Hiperalgesia/fisiopatologia , Medição da Dor/métodos , MasculinoRESUMO
Background: Uncontrolled hypertension is a common problem worldwide, despite the availability of many effective antihypertensive drugs and lifestyle interventions. We assessed the efficacy of a multi-component intervention in individuals with uncontrolled hypertension in a primary care setting. Methods: This study was a randomized, multicenter, parallel, two-arm, single-blind controlled trial performed in primary healthcare centers in Mallorca (Spain). All participants were 35 to 75-years-old and had poorly controlled hypertension. Patients were randomly assigned in a 1:1 ratio to a control group (usual care) or an intervention group (self-monitoring of blood pressure, self-titration of hypertensive medications, dietary interventions, and physical activity interventions). The primary outcome was decrease in the mean SBP at 6 months relative to baseline. Results: A total of 153 participants were randomized to an intervention group (77) or a control group (76). After 6 months, the intervention group had a significantly lower systolic blood pressure (135.1â mmHg [±14.8] vs. 142.7â mmHg [±15.0], adjusted mean difference: 8.7â mmHg [95% CI: 3.4, 13.9], p < 0.001) and a significantly lower diastolic blood pressure (83.5â mmHg [±8.8] vs. 87.00â mmHg [±9.0], adjusted mean difference: 5.4 [95% CI: 2.9, 7.8], p < 0.0001). The intervention group also had significantly more patients who achieved successful blood pressure control (<140/90â mmHg; 54.4% vs. 32.9%, p = 0.011). Discussion: Self-monitoring of blood pressure in combination with self-management of hypertensive medications, diet, and physical activity in a primary care setting leads to significantly lower blood pressure in patients with poorly controlled hypertension.Clinical Trial Registration: ClinicalTrials.gov, identifier ISRCTN14433778.
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Atopic dermatitis is a chronic skin condition that affects up to 20% of children and 10% of adults worldwide. Due to the high burden of dermatological signs and symptoms, atopic dermatitis has a significant impact on the quality of life of patients and their families. In the absence of objective measures to accurately assess severity and symptom burden, patient-reported outcome measures are essential to monitor the impact and progression of the disease, as well as the efficacy of treatments. Although there are currently no standardised guidelines for their use in clinical practice, there are some initiatives, such as the Harmonise Outcome Measures for Eczema and Vivir con Dermatitis Atópica, that can provide guidance. As healthcare systems move towards value-based healthcare models, patient-reported measures are becoming increasingly important for incorporating the patient perspective and improving the quality of healthcare services. The use of these measures can help monitor disease activity and guide treatment decisions. This article discusses the impact of atopic dermatitis and describes the patient-reported outcome measures commonly used in atopic dermatitis and the recommendations of the initiatives that have selected a core set of measures to best assess atopic dermatitis in clinical practice. Considering the recommendations of these initiatives and based on our experience in clinical practice, we propose the use of the Dermatology Life Quality Index to assess the impact of the disease on quality of life, the Patient-Oriented Eczema Measure to assess symptom severity, and the Numerical Rating Scale or the Visual Analogue Scale to measure itch intensity. To systematize the administration of these measures and to integrate them into hospital information systems and medical records, we emphasise the importance of telemedicine platforms that allow the electronic administration of these instruments.
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Capillaries, composed of electrically coupled endothelial cells and overlying pericytes, constitute the vast majority of blood vessels in the brain. The most arteriole-proximate three to four branches of the capillary bed are covered by α-actin-expressing, contractile pericytes. These mural cells have a distinctive morphology and express different markers compared with their smooth muscle cell (SMC) cousins but share similar excitation-coupling contraction machinery. Despite this similarity, pericytes are considerably more depolarized than SMCs at low intravascular pressures. We have recently shown that pericytes, such as SMCs, possess functional voltage-dependent Ca2+ channels and ATP-sensitive K+ channels. Here, we further investigate the complement of pericyte ion channels, focusing on members of the K+ channel superfamily. Using NG2-DsRed-transgenic mice and diverse configurations of the patch-clamp technique, we demonstrate that pericytes display robust inward-rectifier K+ currents that are primarily mediated by the Kir2 family, based on their unique biophysical characteristics and sensitivity to micromolar concentrations of Ba2+. Moreover, multiple lines of evidence, including characteristic kinetics, sensitivity to specific blockers, biophysical attributes, and distinctive single-channel properties, established the functional expression of two voltage-dependent K+ channels: KV1 and BKCa. Although these three types of channels are also present in SMCs, they exhibit distinctive current density and kinetics profiles in pericytes. Collectively, these findings underscore differences in the operation of shared molecular features between pericytes and SMCs and highlight the potential contribution of these three K+ ion channels in setting pericyte membrane potential, modulating capillary hemodynamics, and regulating cerebral blood flow.
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Encéfalo , Capilares , Pericitos , Pericitos/metabolismo , Pericitos/citologia , Animais , Capilares/metabolismo , Capilares/citologia , Camundongos , Encéfalo/irrigação sanguínea , Encéfalo/citologia , Encéfalo/metabolismo , Canais de Potássio/metabolismo , Camundongos Transgênicos , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Camundongos Endogâmicos C57BLRESUMO
Pulmonary arterial (PA) hypertension (PAH) is a severe cardiopulmonary disease that may be triggered by exposure to drugs such as dasatinib or facilitated by genetic predispositions. The incidence of dasatinib-associated PAH is estimated at 0.45%, suggesting individual predispositions. The mechanisms of dasatinib-associated PAH are still incomplete. We discovered a KCNK3 gene (Potassium channel subfamily K member 3; coding for outward K+ channel) variant in a patient with dasatinib-associated PAH and investigated the impact of this variant on KCNK3 function. Additionally, we assessed the effects of dasatinib exposure on KCNK3 expression. In control human PA smooth muscle cells (hPASMCs) and human pulmonary endothelial cells (hPECs), we evaluated the consequences of KCNK3 knockdown on cell migration, mitochondrial membrane potential, ATP production, and in vitro tube formation. Using mass spectrometry, we determined the KCNK3 interactome. Patch-clamp experiments revealed that the KCNK3 variant represents a loss-of-function variant. Dasatinib contributed to PA constriction by decreasing KCNK3 function and expression. In control hPASMCs, KCNK3 knockdown promotes mitochondrial membrane depolarization and glycolytic shift. Dasatinib exposure or KCNK3 knockdown reduced the number of caveolae in hPECs. Moreover, KCNK3 knockdown in control hPECs reduced migration, proliferation, and in vitro tubulogenesis. Using proximity labeling and mass spectrometry, we identified the KCNK3 interactome, revealing that KCNK3 interacts with various proteins across different cellular compartments. We identified a novel pathogenic variant in KCNK3 and showed that dasatinib downregulates KCNK3, emphasizing the relationship between dasatinib-associated PAH and KCNK3 dysfunction. We demonstrated that a loss of KCNK3-dependent signaling contributes to endothelial dysfunction in PAH and glycolytic switch of hPASMCs.
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Dasatinibe , Células Endoteliais , Canais de Potássio de Domínios Poros em Tandem , Dasatinibe/farmacologia , Dasatinibe/efeitos adversos , Humanos , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Canais de Potássio de Domínios Poros em Tandem/genética , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Movimento Celular/efeitos dos fármacos , Hipertensão Arterial Pulmonar/induzido quimicamente , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/patologia , Masculino , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Artéria Pulmonar/efeitos dos fármacos , Proteínas do Tecido NervosoRESUMO
Traumatic brain injury (TBI) represents one of the leading causes of disability and death worldwide. The annual economic impact of TBI-including direct and indirect costs-is high, particularly impacting low- and middle-income countries. Despite extensive research, a comprehensive understanding of the primary and secondary TBI pathophysiology, followed by the development of promising therapeutic approaches, remains limited. These fundamental caveats in knowledge have motivated the development of various experimental models to explore the molecular mechanisms underpinning the pathogenesis of TBI. In this context, the Lateral Fluid Percussion Injury (LFPI) model produces a brain injury that mimics most of the neurological and systemic aspects observed in human TBI. Moreover, its high reproducibility makes the LFPI model one of the most widely used rodent-based TBI models. In this chapter, we provide a detailed surgical protocol of the LFPI model used to induce TBI in adult Wistar rats. We further highlight the neuroscore test as a valuable tool for the evaluation of TBI-induced sensorimotor consequences and their severity in rats. Lastly, we briefly summarize the current knowledge on the pathological aspects and functional outcomes observed in the LFPI-induced TBI model in rodents.
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Lesões Encefálicas Traumáticas , Lesões Encefálicas , Ratos , Humanos , Animais , Percussão/efeitos adversos , Percussão/métodos , Reprodutibilidade dos Testes , Ratos Wistar , Modelos Animais de Doenças , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas/complicações , Lesões Encefálicas/patologiaRESUMO
The arterial myogenic response to intraluminal pressure elicits constriction to maintain tissue perfusion. Smooth muscle [Ca2+] is a key determinant of constriction, tied to L-type (CaV1.2) Ca2+ channels. While important, other Ca2+ channels, particularly T-type could contribute to pressure regulation within defined voltage ranges. This study examined the role of one T-type Ca2+ channel (CaV3.1) using C57BL/6 wild type and CaV3.1-/- mice. Patch-clamp electrophysiology, pressure myography, blood pressure and Ca2+ imaging defined the CaV3.1-/- phenotype relative to C57BL/6. CaV3.1-/- mice had absent CaV3.1 expression and whole-cell current, coinciding with lower blood pressure and reduced mesenteric artery myogenic tone, particularly at lower pressures (20-60 mmHg) where membrane potential is hyperpolarized. This reduction coincided with diminished Ca2+ wave generation, asynchronous events of Ca2+ release from the sarcoplasmic reticulum, insensitive to L-type Ca2+ channel blockade (Nifedipine, 0.3 µM). Proximity ligation assay (PLA) confirmed IP3R1/CaV3.1 close physical association. IP3R blockade (2-APB, 50 µM or xestospongin C, 3 µM) in nifedipine-treated C57BL/6 arteries rendered a CaV3.1-/- contractile phenotype. Findings indicate that Ca2+ influx through CaV3.1 contributes to myogenic tone at hyperpolarized voltages through Ca2+-induced Ca2+ release tied to the sarcoplasmic reticulum. This study helps establish CaV3.1 as a potential therapeutic target to control blood pressure.
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Canais de Cálcio Tipo T , Nifedipino , Camundongos , Animais , Nifedipino/farmacologia , Nifedipino/metabolismo , Sinalização do Cálcio , Vasoconstrição , Camundongos Endogâmicos C57BL , Artérias Mesentéricas/metabolismo , Niacinamida/metabolismo , Músculo Liso Vascular/metabolismo , Cálcio/metabolismo , Canais de Cálcio Tipo T/metabolismoRESUMO
Recent evidence suggests that vitamin D is involved in the development of pulmonary arterial hypertension (PAH). The aim of this study was to analyze the electrophysiological and contractile properties of pulmonary arteries (PAs) in vitamin D receptor knockout mice (Vdr-/-). PAs were dissected and mounted in a wire myograph. Potassium membrane currents were recorded in freshly isolated PA smooth muscle cells (PASMCs) using the conventional whole-cell configuration of the patch-clamp technique. Potential vitamin D response elements (VDREs) in Kv7 channels coding genes were studied, and their protein expression was analyzed. Vdr-/- mice did not show a pulmonary hypertensive phenotype, as neither right ventricular hypertrophy nor endothelial dysfunction was apparent. However, resistance PA from these mice exhibited increased response to retigabine, a Kv7 activator, compared to controls and heterozygous mice. Furthermore, the current sensitive to XE991, a Kv7 inhibitor, was also higher in PASMCs from knockout mice. A possible VDRE was found in the gene coding for KCNE4, the regulatory subunit of Kv7.4. Accordingly, Vdr-/- mice showed an increased expression of KCNE4 in the lungs, with no changes in Kv7.1 and Kv7.4. These results indicate that the absence of Vdr in mice, as occurred with vitamin D deficient rats, is not sufficient to induce PAH. However, the contribution of Kv7 channel currents to the regulation of PA tone is increased in Vdr-/- mice, resembling animals and humans suffering from PAH.
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Canais de Potássio de Abertura Dependente da Tensão da Membrana , Artéria Pulmonar , Animais , Humanos , Camundongos , Ratos , Canais de Potássio KCNQ/metabolismo , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Artéria Pulmonar/metabolismo , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Vitamina D/farmacologia , Vitamina D/metabolismoRESUMO
OBJECTIVE: To develop new antiphospholipid syndrome (APS) classification criteria with high specificity for use in observational studies and trials, jointly supported by the American College of Rheumatology (ACR) and EULAR. METHODS: This international multidisciplinary initiative included 4 phases: 1) Phase I, criteria generation by surveys and literature review; 2) Phase II, criteria reduction by modified Delphi and nominal group technique exercises; 3) Phase III, criteria definition, further reduction with the guidance of real-world patient scenarios, and weighting via consensus-based multicriteria decision analysis, and threshold identification; and 4) Phase IV, validation using independent adjudicators' consensus as the gold standard. RESULTS: The 2023 ACR/EULAR APS classification criteria include an entry criterion of at least one positive antiphospholipid antibody (aPL) test within 3 years of identification of an aPL-associated clinical criterion, followed by additive weighted criteria (score range 1-7 points each) clustered into 6 clinical domains (macrovascular venous thromboembolism, macrovascular arterial thrombosis, microvascular, obstetric, cardiac valve, and hematologic) and 2 laboratory domains (lupus anticoagulant functional coagulation assays, and solid-phase enzyme-linked immunosorbent assays for IgG/IgM anticardiolipin and/or IgG/IgM anti-ß2 -glycoprotein I antibodies). Patients accumulating at least 3 points each from the clinical and laboratory domains are classified as having APS. In the validation cohort, the new APS criteria versus the 2006 revised Sapporo classification criteria had a specificity of 99% versus 86%, and a sensitivity of 84% versus 99%. CONCLUSION: These new ACR/EULAR APS classification criteria were developed using rigorous methodology with multidisciplinary international input. Hierarchically clustered, weighted, and risk-stratified criteria reflect the current thinking about APS, providing high specificity and a strong foundation for future APS research.
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Síndrome Antifosfolipídica , Reumatologia , Feminino , Gravidez , Humanos , Estados Unidos , beta 2-Glicoproteína I , Autoanticorpos , Imunoglobulina G , Imunoglobulina MRESUMO
OBJECTIVE: To develop new antiphospholipid syndrome (APS) classification criteria with high specificity for use in observational studies and trials, jointly supported by the American College of Rheumatology (ACR) and EULAR. METHODS: This international multidisciplinary initiative included four phases: (1) Phase I, criteria generation by surveys and literature review; (2) Phase II, criteria reduction by modified Delphi and nominal group technique exercises; (3) Phase III, criteria definition, further reduction with the guidance of real-world patient scenarios, and weighting via consensus-based multicriteria decision analysis, and threshold identification; and (4) Phase IV, validation using independent adjudicators' consensus as the gold standard. RESULTS: The 2023 ACR/EULAR APS classification criteria include an entry criterion of at least one positive antiphospholipid antibody (aPL) test within 3 years of identification of an aPL-associated clinical criterion, followed by additive weighted criteria (score range 1-7 points each) clustered into six clinical domains (macrovascular venous thromboembolism, macrovascular arterial thrombosis, microvascular, obstetric, cardiac valve, and hematologic) and two laboratory domains (lupus anticoagulant functional coagulation assays, and solid-phase enzyme-linked immunosorbent assays for IgG/IgM anticardiolipin and/or IgG/IgM anti-ß2-glycoprotein I antibodies). Patients accumulating at least three points each from the clinical and laboratory domains are classified as having APS. In the validation cohort, the new APS criteria vs the 2006 revised Sapporo classification criteria had a specificity of 99% vs 86%, and a sensitivity of 84% vs 99%. CONCLUSION: These new ACR/EULAR APS classification criteria were developed using rigorous methodology with multidisciplinary international input. Hierarchically clustered, weighted, and risk-stratified criteria reflect the current thinking about APS, providing high specificity and a strong foundation for future APS research.
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Síndrome Antifosfolipídica , Reumatologia , Feminino , Gravidez , Humanos , Síndrome Antifosfolipídica/diagnóstico , Autoanticorpos , Imunoglobulina G , Imunoglobulina MRESUMO
This study analyse the type of release kinetic of specific monomers from dental resin composites containing various fluoride-doped calcium phosphates. The release behavior of urethane dimethacrylate (UDMA), ethoxylated bisphenol-A dimethacrylate (bis-EMA) and 1.6-hexanediol ethoxylate diacrylate (HEDA) was evaluated over a period of 35 days. Two tailored calcium phosphates doped with different concentrations of fluoride salts (VS10% and VS20%) were prepared and incorporated in the dimethacrylate matrix at various concentrations to generate a range of experimental composites. The release kinetics were characterized using mathematical models such as zero-order, first-order, Peppas and Higuchi models. The results showed that the first-order model best described the release kinetics. UDMA and HEDA exhibited significant differences in release compared to bis-EMA from day 1, while no significant differences were observed between UDMA and HEDA, except on day 35, when UDMA exhibited a higher release rate than HEDA. When comparing the release of each monomer, VS20-R20% had the highest total release percentage, with 3.10 ± 0.25%, whereas the composite VS10-R5% showed the lowest release percentage, with a total of 1.66 ± 0.08%. The release kinetics were influenced by the composition of the resin composites and the presence of calcium fluoride and sodium fluoride in the calcium phosphate played a role in the maximum amounts of monomer released. In conclusion, the release of monomers from the tested resin composites followed a first-order kinetic behaviour, with an initial rapid release that decreased over time. The composition of the resin monomers and the presence of fluoride salts influenced the release kinetics. The VS10-R5% and VS10-R10% resin composites exhibited the lowest total monomer release, suggesting its potential favourable composition with reduced monomer elution. These findings contribute to understanding the release behavior of dental resin composites and provide insights for the development of resin-based bioactive dental materials.
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(1) Background: Falls are a significant health problem among older adults, and can result in severe injuries, disability, and even death. In Spain, the prevalence of falls is lower if the person lives in the community than if they are institutionalized. Research has shown that exercise is an effective strategy for reducing the risk of falls among older adults. The objective of this study was to study the influence of a multicomponent exercise intervention on falls in people between 65 and 80 years of age despite the presence of diseases and drug use that are risk factors for falls; (2) Methods: This is a quasi-experimental study that focuses on people aged 65-80 who attended 21 primary healthcare centres. Target: Inclusion criteria were people between 65 and 80 years of age, living in the community with independent ambulation, and who were served by the healthcare centre of their region. Variables analysed: The number and characteristics of falls, sociodemographic, drug use, and previous diseases; (3) Results: The drugs associated with falls are benzodiazepines (OR 2.58), vasodilators (OR = 2.51), and psychotropics (OR = 1.61). For one of the years, a relationship was found between the consumption of antidepressants and falls (OR = 1.83). The associated diseases were mental and behavioural (OR = 2.53); (4) Discussion: The intervention has been related to the reduction in falls in people who consumed benzodiazepines, vasodilators, and psychotropics and in people with mental disorders; (5) Conclusion: This research concludes the importance of the implementation of the Otago Exercise Programme in the prevention of falls in the elderly.
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Arteriolar smooth muscle cells (SMCs) and capillary pericytes dynamically regulate blood flow in the central nervous system in the face of fluctuating perfusion pressures. Pressure-induced depolarization and Ca2+ elevation provide a mechanism for regulation of SMC contraction, but whether pericytes participate in pressure-induced changes in blood flow remains unknown. Here, utilizing a pressurized whole-retina preparation, we found that increases in intraluminal pressure in the physiological range induce contraction of both dynamically contractile pericytes in the arteriole-proximate transition zone and distal pericytes of the capillary bed. We found that the contractile response to pressure elevation was slower in distal pericytes than in transition zone pericytes and arteriolar SMCs. Pressure-evoked elevation of cytosolic Ca2+ and contractile responses in SMCs were dependent on voltage-dependent Ca2+ channel (VDCC) activity. In contrast, Ca2+ elevation and contractile responses were partially dependent on VDCC activity in transition zone pericytes and independent of VDCC activity in distal pericytes. In both transition zone and distal pericytes, membrane potential at low inlet pressure (20 mmHg) was approximately -40 mV and was depolarized to approximately -30 mV by an increase in pressure to 80 mmHg. The magnitude of whole-cell VDCC currents in freshly isolated pericytes was approximately half that measured in isolated SMCs. Collectively, these results indicate a loss of VDCC involvement in pressure-induced constriction along the arteriole-capillary continuum. They further suggest that alternative mechanisms and kinetics of Ca2+ elevation, contractility, and blood flow regulation exist in central nervous system capillary networks, distinguishing them from neighboring arterioles.
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Cálcio , Pericitos , Pericitos/metabolismo , Cálcio/metabolismo , Canais de Cálcio Tipo L , Arteríolas/fisiologia , Sistema Nervoso Central/metabolismo , Cálcio da DietaRESUMO
Hydrogen sulfide (H2S) is a unique signaling molecule that, along with carbon monoxide and nitric oxide, belongs to the gasotransmitters family. H2S is endogenously synthesized by enzymatic and non-enzymatic pathways. Three enzymatic pathways involving cystathionine-γ-lyase, cystathionine-ß-synthetase, and 3-mercaptopyruvate sulfurtransferase are known as endogenous sources of H2S. This gaseous molecule has recently emerged as a regulator of many systems and physiological functions, including the cardiovascular system where it controls the vascular tone of small arteries. In this context, H2S leads to vasorelaxation by regulating the activity of vascular smooth muscle cells, endothelial cells, and perivascular nerves. Specifically, H2S modulates the functionality of different ion channels to inhibit the autonomic sympathetic outflow-by either central or peripheral mechanisms-or to stimulate perivascular sensory nerves. These mechanisms are particularly relevant for those pathological conditions associated with impaired neuromodulation of vascular tone. In this regard, exogenous H2S administration efficiently attenuates the increased activity of the sympathetic nervous system often seen in patients with certain pathologies. These effects of H2S on the autonomic sympathetic outflow will be the primary focus of this review. Thereafter, we will discuss the central and peripheral regulatory effects of H2S on vascular tone. Finally, we will provide the audience with a detailed summary of the current pathological implications of H2S modulation on the neural regulation of vascular tone.
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Gasotransmissores , Sulfeto de Hidrogênio , Humanos , Sulfeto de Hidrogênio/metabolismo , Células Endoteliais/metabolismo , Gasotransmissores/metabolismo , Neurotransmissores/farmacologia , Transdução de SinaisRESUMO
Cerebral arteries contain two primary and interacting cell types, smooth muscle (SMCs) and endothelial cells (ECs), which are each capable of sensing particular hemodynamic forces to set basal tone and brain perfusion. These biomechanical stimuli help confer tone within arterial networks upon which local neurovascular stimuli function. Tone development is intimately tied to arterial membrane potential (V M ) and changes in intracellular [Ca2+] driven by voltage-gated Ca2+ channels (VGCCs). Arterial V M is in turn set by the dynamic interplay among ion channel species, the strongly inward rectifying K+ (Kir) channel being of special interest. Kir2 channels possess a unique biophysical signature in that they strongly rectify, display negative slope conductance, respond to elevated extracellular K+ and are blocked by micromolar Ba2+. While functional Kir2 channels are expressed in both smooth muscle and endothelium, they lack classic regulatory control, thus are often viewed as a simple background conductance. Recent literature has provided new insight, with two membrane lipids, phosphatidylinositol 4,5-bisphosphate (PIP2) and cholesterol, noted to (1) stabilize Kir2 channels in a preferred open or closed state, respectively, and (2) confer, in association with the cytoskeleton, caveolin-1 (Cav1) and syntrophin, hemodynamic sensitivity. It is these aspects of vascular Kir2 channels that will be the primary focus of this review.
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Morbidity is the main item in the distribution of expenditure on healthcare services. The Adjusted Morbidity Group (AMG) measures comorbidity and complexity and classifies the patient into mutually exclusive clinical categories. The aim of this study is to analyse the variability of healthcare expenditure on users with similar scores classified by the AMG. Observational analytical and retrospective study. Population: 1,691,075 subjects, from Canary Islands (Spain), aged over 15 years with data from health cards, clinical history, Basic Minimum Specialised Healthcare Data Set, AMG, hospital agreements information system and Electronic Prescriptions. A descriptive, bivariant (ANOVA coefficient η2) and multivariant analysis was conducted. There is a correlation between the costs and the weight of AMG (rho = 0.678) and the prescribed active ingredients (rho = 0.689), which is smaller with age and does not exist with the other variables. As for the influence of the AMG morbidity group on the total costs of the patient, the coefficient η2 (0.09) obtains a median effect in terms of the variability of expenditure, hence there is intra- and inter-group variability in the cost. In a first model created with all the variables and the cost, an explanatory power of 36.43% (R2 = 0.3643) was obtained; a second model that uses solely active ingredients, AMG weight, being female and a pensioner obtained an explanatory power of 36.4%. There is room for improvement in terms of predicting the expenditure.
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Atenção à Saúde , Gastos em Saúde , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Morbidade , Estudos Retrospectivos , Espanha/epidemiologiaRESUMO
The dense network of capillaries composed of capillary endothelial cells (cECs) and pericytes lies in close proximity to all neurons, ideally positioning it to sense neuron- and glial-derived compounds that enhance regional and global cerebral perfusion. The membrane potential (VM) of vascular cells serves as the physiological bridge that translates brain activity into vascular function. In other beds, the ATP-sensitive K+ (KATP) channel regulates VM in vascular smooth muscle, which is absent in the capillary network. Here, with transgenic mice that expressed a dominant-negative mutant of the pore-forming Kir6.1 subunit specifically in brain cECs or pericytes, we demonstrated that KATP channels were present in both cell types and robustly controlled VM. We further showed that the signaling nucleotide adenosine acted through A2A receptors and the Gαs/cAMP/PKA pathway to activate capillary KATP channels. Moreover, KATP channel stimulation in vivo increased cerebral blood flow (CBF), an effect that was blunted by expression of the dominant-negative Kir6.1 mutant in either capillary cell type. These findings establish an important role for KATP channels in cECs and pericytes in the regulation of CBF.
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Células Endoteliais , Pericitos , Adenosina , Trifosfato de Adenosina/metabolismo , Animais , Capilares/metabolismo , Células Endoteliais/metabolismo , Canais KATP/genética , Canais KATP/metabolismo , Camundongos , Pericitos/metabolismoRESUMO
Glomerular filtration is a pivotal process of renal physiology, and its alterations are a central pathological event in acute kidney injury and chronic kidney disease. Creatinine clearance (ClCr), a standard method for glomerular filtration rate (GFR) measurement, requires a long and tedious procedure of timed (usually 24 h) urine collection. We have developed a neural network (NN)-based calculator of rat ClCr from plasma creatinine (pCr) and body weight. For this purpose, matched pCr, weight, and ClCr trios from our historical records on male Wistar rats were used. When evaluated on the training (1165 trios), validation (389), and test sets (660), the model committed an average prediction error of 0.196, 0.178, and 0.203 mL/min and had a correlation coefficient of 0.863, 0.902, and 0.856, respectively. More importantly, for all datasets, the NN seemed especially effective at comparing ClCr among groups within individual experiments, providing results that were often more congruent than those measured experimentally. ACLARA, a friendly interface for this calculator, has been made publicly available to ease and expedite experimental procedures and to enhance animal welfare in alignment with the 3Rs principles by avoiding unnecessary stressing metabolic caging for individual urine collection.
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BACKGROUND: Falls are a major public health problem. Fear of falling is highly prevalent amongst community-dwelling older adults who have already fallen and it is also a risk factor for recurrent falls. There has been limited research about the impact that exercises programs have on the fear of falling. The aim of this study was to evaluate whether the Otago Exercise Programme (OEP) reduced the fear of falling in non-institutionalised people aged 65-80 years in Spain. It also evaluated the factors associated with the fear of falling. METHODS: This was a quasi-experimental study that focused on people aged 65-80 who attended 21 primary healthcare centres, lived in the community, were able to walk independently and provided written, informed consent. They were recruited from September 2017 to December 2019. The OEP sessions took place at the primary healthcare centres and were provided on an individual or group basis by trained OEP instructors. The participants attended five weekly sessions, where they were given exercises to develop their strength, balance and endurance. They then continued the programme at home. The subjects were followed up 12 months after baseline and the analyses included a bivariate analysis and a multivariate analysis with logistic regression. RESULTS: We enroled 498 patients (67.07% female) with an average age of 71.81 years. More than two-thirds (65.06%) lived with a partner and 42.37% were overweight. Significant reductions were observed in the mean level of fear of falling between baseline and 12 months (p = 0.000). A number of factors associated with fear of falling also showed significant differences. These were: age (p = 0.033), sex (p = 0.000), living alone (p = 0.000), body mass index (p = 0.003) and whether psychotropic drugs were used (p = 0.000). The multivariate analysis showed a moderate to high fear of falling amongst participants who were female (p = 0.000), 72-80 years of age (p = 0.017), obese (p = 0.045) and used psychotropic drugs (p = 0.021). CONCLUSIONS: Taking part in the OEP reduced the overall fear of falling. There were significant associations between fear of falling and being female, taking psychotic drugs and having a history of falls. This study is a quasi-experimental sign nested an experimental study (randomized controlled trial previously published and registered on ClinicalTrials.org (NCT03320668)). Retrospectively registered on 25/10/2017.