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Matrix metalloproteinases (MMPs) such as MMP-9, 3, and 2 degrade the cellular matrix and are believed to play a crucial role in ischemic stroke. We examined how the duration of ischemia (up to 4 h) and treatment with recombinant tissue plasminogen activator altered the comparative expression of these MMPs in experimental ischemic stroke with reperfusion. Both prolonged ischemia and r-tPA treatment markedly increased MMP-9 expression in the ischemic hemisphere (all p < 0.0001). The duration of ischemia and r-tPA treatment also significantly increased MMP-2 expression (p < 0.01-0.001) in the ischemic hemisphere (p < 0.01) but to a lesser degree than MMP-9. In contrast, MMP-3 expression significantly decreased in the ischemic hemisphere (p < 0.001) with increasing duration of ischemia and r-tPA treatment (p < 0.05-0001). MMP-9 expression was prominent in the vascular compartment and leukocytes. MMP-2 expression was evident in the vascular compartment and MMP-3 in NeuN+ neurons. Prolonging the duration of ischemia (up to 4 h) before reperfusion increased brain hemorrhage, infarction, swelling, and neurologic disability in both saline-treated (control) and r-tPA-treated mice. MMP-9 and MMP-2 expression were significantly positively correlated with, and MMP-3 was significantly negatively correlated with, infarct volume, swelling, and brain hemorrhage. We conclude that in experimental ischemic stroke with reperfusion, the duration of ischemia and r-tPA treatment significantly altered MMP-9, 3, and 2 expression, ischemic brain injury, and neurological disability. Each MMP showed unique patterns of expression that are strongly correlated with the severity of brain infarction, swelling, and hemorrhage. In summary, in experimental ischemic stroke in male mice with reperfusion, the duration of ischemia, and r-tPA treatment significantly altered the immunofluorescent expression of MMP-9, 3, and 2, ischemic brain injury, and neurological disability. In this model, each MMP showed unique patterns of expression that were strongly correlated with the severity of brain infarction, swelling, and hemorrhage.
Assuntos
Isquemia Encefálica , Metaloproteinase 2 da Matriz , Metaloproteinase 3 da Matriz , Metaloproteinase 9 da Matriz , Ativador de Plasminogênio Tecidual , Animais , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , Fatores de TempoRESUMO
Venous thrombosis and pulmonary embolism (venous thromboembolism) are important causes of morbidity and mortality worldwide. In patients with venous thromboembolism, thrombi obstruct blood vessels and resist physiological dissolution (fibrinolysis), which can be life threatening and cause chronic complications. Plasminogen activator therapy, which was developed >50 years ago, is effective in dissolving thrombi but has unacceptable bleeding risks. Safe dissolution of thrombi in patients with venous thromboembolism has been elusive despite multiple innovations in plasminogen activator design and catheter-based therapy. Evidence now suggests that fibrinolysis is rigidly controlled by endogenous fibrinolysis inhibitors, including α2-antiplasmin, plasminogen activator inhibitor-1, and thrombin-activable fibrinolysis inhibitor. Elevated levels of these fibrinolysis inhibitors are associated with an increased risk of venous thromboembolism in humans. New therapeutic paradigms suggest that accelerated and effective fibrinolysis may be achieved safely by therapeutically targeting these fibrinolytic inhibitors in venous thromboembolism. In this article, we discuss the role of fibrinolytic components in venous thromboembolism and the current status of research and development targeting fibrinolysis inhibitors.
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Fibrinólise , Fibrinolíticos , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/tratamento farmacológico , Fibrinólise/efeitos dos fármacos , Fibrinolíticos/uso terapêutico , Fibrinolíticos/efeitos adversos , Terapia Trombolítica/métodos , Animais , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Inibidor 1 de Ativador de Plasminogênio/uso terapêuticoRESUMO
Symptomatic heart failure (sHF) with cardiac dysfunction, edema, and mortality are driven by overactivation of the renin-angiotensin-aldosterone system (RAAS). Renin is widely recognized as a key initiator of RAAS function, yet the mechanisms that activate renin remain a mystery. We discovered that activated coagulation factor XII generates active renin in the circulation and is directly linked to pathological activation of the systemic RAAS, development of sHF, and increased mortality. These findings suggest a new paradigm for therapeutically modulating the RAAS in sHF and other pathological conditions.
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Triiodothyronine (T3) concentrations in plasma decrease during acute illness and it is unclear if this contributes to disease. Clinical and laboratory studies of T3 supplementation in disease have revealed little or no effect. It is uncertain if short term supplementation of T3 has any discernible effect in a healthy animals. Observational study of intravenous T3 (1 µg/kg/h) for 24 h in a healthy sheep model receiving protocol-guided intensive care supports (T3 group, n=5). A total of 45 endpoints were measured including hemodynamic, respiratory, renal, hematological, metabolic and endocrine parameters. Data were compared with previously published studies of sheep subject to the same support protocol without administered T3 (No T3 group, n=5). Plasma free T3 concentrations were elevated 8-fold by the infusion (pmol/l at 24 h; T3 group 34.9±9.9 vs. No T3 group 4.4±0.3, P<0.01, reference range 1.6 to 6.8). There was no significant physiological response to administration of T3 over the study duration. Supplementation of intravenous T3 for 24 h has no physiological effect on relevant physiological endpoints in healthy sheep. Further research is required to understand if the lack of effect of short-term T3 may be related to kinetics of T3 cellular uptake, metabolism and action, or acute counterbalancing hormone resistance. This information may be helpful in design of clinical T3 supplementation trials.
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Arritmias Cardíacas , Cardiomiopatias , Fibrose , Hipertensão , Serina Endopeptidases , Humanos , Arritmias Cardíacas/genética , Cardiomiopatias/genética , Fibrose/genética , Átrios do Coração/patologia , Átrios do Coração/diagnóstico por imagem , Hipertensão/genética , Serina Endopeptidases/genéticaRESUMO
This study aimed to evaluate the utility and applicability of electrooculography (EOG) when studying ocular activity during complex motor behavior. Due to its lower spatial resolution relative to eye tracking (ET), it is unclear whether EOG can provide valid and accurate temporal measurements such as the duration of the Quiet Eye (QE), that is the uninterrupted dwell time on the visual target prior to and during action. However, because of its greater temporal resolution, EOG is better suited for temporal-spectral decomposition, a technique that allows us to distinguish between lower and higher frequency activity as a function of time. Sixteen golfers of varying expertise (novices to experts) putted 60 balls to a 4-m distant target on a flat surface while we recorded EOG, ET, performance accuracy, and putter kinematics. Correlational and discrepancy analyses confirmed that EOG yielded valid and accurate QE measurements, but only when using certain processing parameters. Nested cross-validation indicated that, among a set of ET and EOG temporal and spectral oculomotor features, EOG power was the most useful when predicting performance accuracy through robust regression. Follow-up cross-validation and correlational analyses revealed that more accurate performance was preceded by diminished lower-frequency activity immediately before movement initiation and elevated higher-frequency activity during movement recorded from the horizontal channel. This higher-frequency activity was also found to accompany a smoother movement execution. This study validates EOG algorithms (code provided) for measuring temporal parameters and presents a novel approach to extracting temporal and spectral oculomotor features during complex motor behavior.
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Algoritmos , Movimentos Oculares , Humanos , Eletroculografia/métodos , Tecnologia de Rastreamento Ocular , Fenômenos BiomecânicosRESUMO
BACKGROUND: Initiatives in perioperative care warrant robust cost-effectiveness analysis in a cost-constrained era when high-value care is a priority. A model of anesthesia-led early high-acuity postoperative care, advanced recovery room care (ARRC), has shown benefit in terms of hospital and patient outcomes, but its cost-effectiveness has not yet been formally determined. METHODS: Data from a previously published single-center prospective cohort study of ARRC in medium-risk patients were used to generate a Markov model, which described patient transition between care locations, each with different characteristics and costs. The incremental cost-effectiveness ratio (ICER), using days at home (DAH) and hospital costs, was calculated for ARRC compared to usual ward care using deterministic and probabilistic sensitivity analysis. RESULTS: The Markov model accurately described patient disposition after surgery. For each patient, ARRC provided 4.3 more DAH within the first 90 days after surgery and decreased overall hospital costs by $1081 per patient. Probabilistic sensitivity analysis revealed that ARRC had a 99.3% probability of increased DAH and a 77.4% probability that ARRC was dominant from the perspective of the hospital, with improved outcomes and decreased costs. CONCLUSIONS: Early high-acuity care for approximately 24 hours after surgery in medium-risk patients provides highly cost-effective improvements in outcomes when compared to usual ward care.
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Funding the research needed to advance our understanding of rare cancers is very challenging [...].
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BACKGROUND: Duchenne muscular dystrophy (DMD) is a severe form of muscular dystrophy without an effective treatment, caused by mutations in the DMD gene, leading to the absence of dystrophin. DMD results in muscle weakness, loss of ambulation, and death at an early age. Metabolomics studies in mdx mice, the most used model for DMD, reveal changes in metabolites associated with muscle degeneration and aging. In DMD, the tongue muscles exhibit unique behavior, initially showing partial protection against inflammation but later experiencing fibrosis and loss of muscle fibers. Certain metabolites and proteins, like TNF-α and TGF-ß, are potential biomarkers for dystrophic muscle characterization. METHODS: To investigate disease progression and aging, we utilized young (1 month old) and old (21-25 months old) mdx and wild-type tongue muscles. Metabolite changes were analyzed using 1H nuclear magnetic resonance, while TNF-α and TGF-ß were assessed using Western blotting to examine inflammation and fibrosis. Morphometric analysis was conducted to assess the extent of myofiber damage between groups. RESULTS: The histological analysis of the mid-belly tongue showed no differences between groups. No differences were found between the concentrations of metabolites from wild-type or mdx whole tongues of the same age. The metabolites alanine, methionine, and 3-methylhistidine were higher, and taurine and glycerol were lower in young tongues in both wild type and mdx (p < 0.001). The metabolites glycine (p < 0.001) and glutamic acid (p = 0.0018) were different only in the mdx groups, being higher in young mdx mice. Acetic acid, phosphocreatine, isoleucine, succinic acid, creatine, and the proteins TNF-α and TGF-ß had no difference in the analysis between groups (p > 0.05). CONCLUSIONS: Surprisingly, histological, metabolite, and protein analysis reveal that the tongue of old mdx remains partially spared from the severe myonecrosis observed in other muscles. The metabolites alanine, methionine, 3-methylhistidine, taurine, and glycerol may be effective for specific assessments, although their use for disease progression monitoring should be cautious due to age-related changes in the tongue muscle. Acetic acid, phosphocreatine, isoleucine, succinate, creatine, TNF-α, and TGF-ß do not vary with aging and remain constant in spared muscles, suggesting their potential as specific biomarkers for DMD progression independent of aging.
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Distrofia Muscular de Duchenne , Camundongos , Animais , Distrofia Muscular de Duchenne/genética , Fator de Necrose Tumoral alfa/genética , Creatina , Camundongos Endogâmicos mdx , Fosfocreatina , Glicerol , Isoleucina , Fibras Musculares Esqueléticas , Metionina , Racemetionina , Ácido Acético , Alanina , Progressão da DoençaRESUMO
To evaluate the impact of elevator travel on intraocular pressure after vitreoretinal surgery with gas tamponade. Patients undergoing pars plana vitreoretinal surgery with and without gas insertion were recruited on post-operative day 1. All intraocular pressures were measured three times by Tono-Pen AVIA (Reichert, USA) on the fourth floor and, after rapid ascent in an elevator, on the 12th floor of the hospital. All patients were observed and asked for any symptoms of pain or nausea for at least 15 min. In this study, 54 patients were recruited. Twenty-seven patients underwent vitreoretinal procedures with gas insertion, while 27 patients without gas insertion acted as controls. The mean age of patients was 60.9 years. The mean changes in intraocular pressure of the patients with gas insertion (+ 1.39 mmHg) were greater than those without gas insertion (- 0.43 mmHg) and statistically significantly different (95% CI 1.17-2.48, P < 0.0001). Patients undergoing vitreoretinal surgery with gas insertion had statistically significant intraocular pressure rise even with 8-floor ascent in the immediate post-operative period. Further studies are needed to evaluate the change in intraocular pressure with a larger range of altitudes and different gases.
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Oftalmopatias , Pressão Intraocular , Humanos , Pessoa de Meia-Idade , Elevadores e Escadas Rolantes , Vitrectomia/efeitos adversos , Tonometria Ocular , GasesRESUMO
Improving the performance of a supercapacitor is one of the main approaches to solve the energy shortage problem. Electrode material is one of the key components limiting the efficiency of a supercapacitor. Discovering, tuning, and improving electrode materials are very important. This work reports the effect of SiO2/Al2O3 ratio on electrochemical performances of amorphous zeolites ZSM5 (AZ) and H-ZSM5 (H-AZ) loaded with cobalt oxide. Two SiO2/Al2O3 ratios (1 = 6.2 and 2 = 8.3) of AZ1, AZ2 and H-AZ1, H-AZ2 were synthesized by a facile impregnation method. Then, controlled masses of cobalt oxide were introduced to enhance the supercapacitive performances of the amorphous zeolite. Investigation of the SiO2/Al2O3 ratio in the cobalt oxide/zeolite composite (Co/AZ and Co/H-AZ) was carried out to unveil its effect on the electrochemical properties. Worthy of note is the fact that the resulting electrode materials exhibited supercapacitive behavior that is effective over a potential window ranging from 0 to 0.5 V in potassium hydroxide (1 M KOH) aqueous electrolyte. Results from Galvanometry Charging and Discharging (GCD) analyses show that the modified Ni-foam electrodes loaded with Co/H-AZ1 and Co/H-AZ2 are capable of delivering a relatively high specific capacity from 45.97 mA h g-1 to a high value of 72.5 mA h g-1 at 1 A g-1 and Ni-foam electrodes loaded with Co/AZ1 and Co/AZ2 exhibited values from 26 mA h g-1 to 52.83 mA h g-1 respectively. It is clearly shown that, when the mass ratio SiO2/Al2O3 increases, the specific capacity increases as well. It was also noticed that after 2000 cycles, Co/H-AZ1 and Co/AZ1 have a poor coulombic efficiency while Co/H-AZ2 and Co/AZ2 exhibited 98% for coulombic efficiency. Finally, this study shows that to fabricate high performance supercapacitors with amorphous zeolite loaded with cobalt oxide, one should keep the ratio of SiO2/Al2O3 as high as possible during synthesis.
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Background: Duchenne muscular dystrophy (DMD) is a severe form of muscular dystrophy without an effective treatment, caused by mutations in the DMD gene, leading to the absence of dystrophin. DMD results in muscle weakness, loss of ambulation and death at an early age. Metabolomics studies in mdx mice, the most used model for DMD, reveal changes in metabolites associated with muscle degeneration and aging. In DMD, the tongue muscles exhibit unique behavior, initially showing partial protection against inflammation but later experiencing fibrosis and loss of muscle fibers. Certain metabolites and proteins, like TNF-α and TGF-ß, are potential biomarkers for dystrophic muscle characterization. Methods: To investigate disease progression and aging, we utilized young (1-month old) and old (21-25 months old) mdx and wild-type mice. Metabolite changes were analyzed using 1-H Nuclear Magnetic Resonance, while TNF-α and TGF-ß were assessed using Western blotting to examine inflammation, and fibrosis. Morphometric analysis was conducted to assess the extent of myofiber damage between groups. Results: The histological analysis of the tongue showed no differences between groups. No differences were found between the concentrations of metabolites from wild type or mdx animals of the same age. The metabolites alanine, methionine, 3-methylhistidine were higher, and taurine and glycerol were lower in young animals in both wild type and mdx (p < 0.001). The metabolites glycine (p < 0.001) and glutamic acid (p = 0.0018) were different only in the mdx groups, being higher in young mdx mice. Acetic acid, phosphocreatine, isoleucine, succinic acid, creatine and the proteins TNF-α and TGF-ß had no difference in the analysis between groups (p > 0.05). Conclusions: Surprisingly, histological and protein analysis reveals that the tongue of young and old mdx animals is protected from severe myonecrosis observed in other muscles. The metabolites alanine, methionine, 3-methylhistidine, taurine, and glycerol may be effective for specific assessments, although their use for disease progression monitoring should be cautious due to age-related changes. Acetic acid, phosphocreatine, isoleucine, succinate, creatine, TNF-α, and TGF-ß do not vary with aging and remain constant in spared muscles, suggesting their potential as specific biomarkers for DMD progression independent of aging.
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BACKGROUND & AIMS: The cause of Crohn's disease (CD) is unknown, but the current hypothesis is that microbial or environmental factors induce gut inflammation in genetically susceptible individuals, leading to chronic intestinal inflammation. Case-control studies of patients with CD have cataloged alterations in the gut microbiome composition; however, these studies fail to distinguish whether the altered gut microbiome composition is associated with initiation of CD or is the result of inflammation or drug treatment. METHODS: In this prospective cohort study, 3483 healthy first-degree relatives (FDRs) of patients with CD were recruited to identify the gut microbiome composition that precedes the onset of CD and to what extent this composition predicts the risk of developing CD. We applied a machine learning approach to the analysis of the gut microbiome composition (based on 16S ribosomal RNA sequencing) to define a microbial signature that associates with future development of CD. The performance of the model was assessed in an independent validation cohort. RESULTS: In the validation cohort, the microbiome risk score (MRS) model yielded a hazard ratio of 2.24 (95% confidence interval, 1.03-4.84; P = .04), using the median of the MRS from the discovery cohort as the threshold. The MRS demonstrated a temporal validity by capturing individuals that developed CD up to 5 years before disease onset (area under the curve > 0.65). The 5 most important taxa contributing to the MRS included Ruminococcus torques, Blautia, Colidextribacter, an uncultured genus-level group from Oscillospiraceae, and Roseburia. CONCLUSION: This study is the first to demonstrate that gut microbiome composition is associated with future onset of CD and suggests that gut microbiome is a contributor in the pathogenesis of CD.
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Doença de Crohn , Microbioma Gastrointestinal , Inflamação , Humanos , Inflamação/genética , Estudos Prospectivos , Faecalibacterium , Complexo Antígeno L1 LeucocitárioRESUMO
Clinical manifestations and courses of eye diseases in children are profoundly variable, from minor irritations, pain, infections, inflammations, ocular misalignment, refractive errors and visual impairment, to permanent blindness [...].