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Adrenergic receptors of the ß3-subtype (ß3-ADRs) seem to represent a new target for a more effective pharmacological treatment of overactive bladder (OAB), a wide spread urinary disorder. A promising opportunity for OAB therapy might rely on the development of selective ß3-ADR agonists, but an appropriate preclinical screening, as well as investigation of their pharmacological mechanism(s), is limited by poor availability of human bladder samples and of translational animal models. In this study, we used the porcine urinary bladder as experimental tool to ascertain the functions of ß3-ADRs in the control the parasympathetic motor drive. Tritiated acetylcholine ([3H]-ACh), mainly originated from neural stores, was released by electrical field stimulation (EFS) in epithelium-deprived detrusor strips from pigs bred without estrogens. EFS produced simultaneously [3H]-ACh release and smooth muscle contraction allowing to asses neural (pre-junctional) and myogenic (postjunctional) effects in the same experiment. Isoprenaline and mirabegron produced on the EFS-evoked effects a concentration-dependent inhibition antagonized by L-748,337, a high selective ß3-ADR antagonist. The analysis of the resultant pharmacodynamic parameters supports the notion that in pig detrusors, as well as in previously described human detrusors, the activation of inhibitory ß3-ADRs can modulate neural parasympathetic pathways. In such inhibitory control, the involvement of membrane K+ channels, mainly of the SK type, seems to play a pivotal role similarly to what previously described in humans. Therefore, the isolated porcine detrusor can provide a suitable experimental tool to study the mechanisms underlying the clinical efficacy of selective ß3-ADR compounds for human use.
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OBJECTIVE: The purpose of this study was to describe the incidence, characteristics, and outcomes of cardiac arrest in the air medical environment so that we can begin to understand predictors of in-flight cardiac arrest and identify opportunities to improve care. METHODS: This retrospective observational study was undertaken at Airlift Northwest from 2013 to 2017. Descriptive statistics of adult patients with medical and traumatic etiologies of cardiac arrest were analyzed and compared. RESULTS: Of the 13,915 adult patients transported during the study period, fewer than 1% (Nâ¯=â¯92) had a cardiac arrest during transport. Of those, 42% in the overall cohort had return of spontaneous circulation on arrival at the destination hospital. Medical etiologies of cardiac arrest were more common than traumatic (65% vs. 35%), more likely to have an initial shockable rhythm (30% vs. 3%, Pâ¯=â¯.004), and more frequently arrived at the receiving hospital with return of spontaneous circulation (57% vs. 31%, Pâ¯=â¯.03). Rearrest in transport occurred frequently (39%). Most patients were hypotensive before cardiac arrest, and peri-intubation cardiac arrest occurred in 12% of patients. CONCLUSION: Cardiac arrest during air medical transport is a rare event that requires a high level of critical care to treat refractory cardiac arrests, hemodynamic instability, and airway compromise.
Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Adulto , Cuidados Críticos , Humanos , Estudos RetrospectivosRESUMO
The purposes of this retrospective study were to document the prevalence of serum C-reactive protein (CRP), a biomarker of inflammation, and its potential predictive value for Rehabilitation outcomes in post-acute elderly inpatients. The medical records of 304 elderly subjects admitted to our Rehabilitation Institute for any disease following an acute event were examined. High levels of CRP (> 0.5 mg/dl) were present in 100% of the subjects, and the value > 1.5 mg/dl (n = 86) predicted unfavourable outcomes (n = 28; 32.5% of the patients: death or transfer to other institutions). Among the patients with favourable outcomes (discharge home n = 255), 62.7% still exhibited severe disabilities. Pressure ulcers and low functional status also predicted unfavourable outcomes. The study highlights the need for future investigations into the possible reduction of CRP levels, after an intensive nutritional approach and combined physical interventions.
Assuntos
Úlcera por Pressão , Idoso , Estado Funcional , Humanos , Inflamação , Úlcera por Pressão/epidemiologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
INTRODUCTION: Seattle Mountain Rescue (SMR) is a nonprofit, volunteer organization that provides mountain rescue services in King County, Washington. This study analyzed the medical care provided by SMR over 14 y to understand the challenges in patient care in the region and to perform data collection and monitoring. METHODS: A retrospective review of mission reports submitted from 2004 to 2017 was conducted. Date, location, demographics, activity, callout reason, chief complaint, treatments provided, extraction means, and helicopter utilization were analyzed. Data are presented as mean±SD, with range as appropriate, unless otherwise noted. Linear regression was used to estimate changes in mission volume over time. RESULTS: There were 552 missions involving 756 subjects during the study period. Mission totals increased by 4 (95% CI 2-6, P<0.001) per year. Four locations accounted for 38% of mission volume. Subject age was 36±18 y, and 59% of subjects were male. The most common activity leading to rescue was hiking (80%). Injuries or illness precipitated 58% of callouts, whereas lost, stranded, or overdue subjects comprised 40%. For subjects requiring medical treatment, 81% involved a traumatic injury, 64% were packaged in a litter, and 35% required splinting. CONCLUSIONS: The frequency of mountain rescue missions in King County, Washington, has increased in the past 14 y, with traumatic injuries most frequently requiring medical care. Missing data were common in most categories, and nonstandardized reports challenged research efforts. This study provides a baseline for future research and data collection and adds to the literature regarding the medical care provided during mountain rescue incidents.
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Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/terapia , Trabalho de Resgate , Adolescente , Adulto , Serviços Médicos de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Esportes , Washington , Adulto JovemRESUMO
Airway management and maintenance of adequate ventilation during a patient's unattended helicopter rescue hoist extraction present unique challenges to the air medical provider. We present the case of a critically injured patient requiring emergent airway management and subsequent extrication via hoist from challenging, near-vertical terrain, which illustrates the logistical challenges of providing high-quality, neuroprotective mechanical ventilation in an austere air medical scenario.
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Resgate Aéreo , Intubação Intratraqueal , Montanhismo/lesões , Trabalho de Resgate/métodos , Humanos , Masculino , Adulto JovemRESUMO
Conflicting results about alterations of plasma amino acid (AA) levels are reported in subjects with Alzheimer's disease (AD). The current study aimed to provide more homogeneous AA profiles and correlations between AAs and cognitive tests. Venous plasma AAs were measured in 54 fasting patients with AD (37 males, 17 females; 74.63 ± 8.03 yrs; 3.2 ± 1.9 yrs from symptom onset). Seventeen matched subjects without neurodegenerative symptoms (NNDS) served as a control group (C-NNDS). Patients were tested for short-term verbal memory and attention capacity and stratified for nutritional state (Mini Nutritional Assessment, MNA). Compared to C-NNDS, patients exhibited lower plasma levels of aspartic acid and taurine (p < 0.0001) and higher 3-methylhistidine (p < 0.0001), which were independent of patients' MNA. In comparison to normonourished AD, the patients at risk of and with malnutrition showed a tendency towards lower ratios of Essential AAs/Total AAs, Branched-chain AAs/Total AAs, and Branched-chain AAs/Essential AAs. Serine and histidine were positively correlated with verbal memory and attention capacity deficits, respectively. Total AAs negatively correlated with attention capacity deficits. Stratifying patients with AD for MNA may identify a dual pattern of altered AAs, one due to AD per se and the other linked to nutritional state. Significant correlations were observed between several AAs and cognitive tests.
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Doença de Alzheimer/sangue , Aminoácidos/sangue , Estado Nutricional , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Atenção , Feminino , Histidina/sangue , Humanos , Masculino , Desnutrição/sangue , Desnutrição/complicações , Memória , Transtornos da Memória/sangue , Avaliação Nutricional , Serina/sangueRESUMO
Chemotherapy for colorectal cancer may lower muscle protein synthesis and increase oxidative stress. We hypothesize that chemotherapy may worsen plasma amino acids (AAs) and markers of oxidative stress (MOS). Therefore, this study aimed to document plasma AAs and MOS before, during and after chemotherapy in colorectal cancer (CRC) surgery patients. Fourteen normal-weight CRC patients were enrolled one month after surgery and scheduled for oxaliplatin-fluoropyrimidine combination (XELOX) therapy. Venous blood samples for AA and MOS (malondialdehyde, MDA; 8-hydroxy-2'-deoxyguanosine, 8-OHdG) measurements were drawn in fasting patients before each oxaliplatin infusion at initiation (A), 1 month (B) and 3 months (C) of the therapy, and after XELOX had finished (6 months, D). The results showed that during XELOX therapy (from phase B to phase D), in comparison to baseline (phase A), the branched chain amino acid/essential amino acid ratio, branched chain amino acids expressed as a percentage of total AAs, and arginine expressed as a percentage of total AAs significantly decreased (p = 0.017, p = 0.028, p = 0.028, respectively). Plasma levels of MOS did not change significantly. This study indicates that XELOX therapy does not affect plasma AA levels or worsen oxidative stress.
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Aminoácidos/sangue , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Capecitabina/farmacologia , Neoplasias Colorretais/sangue , Neoplasias Colorretais/tratamento farmacológico , Oxaloacetatos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , 8-Hidroxi-2'-Desoxiguanosina/sangue , Arginina/sangue , Colectomia , Neoplasias Colorretais/cirurgia , Jejum/sangue , Feminino , Humanos , Estudos Longitudinais , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Projetos Piloto , Período Pós-Operatório , Estudos ProspectivosRESUMO
BACKGROUND: Systemic inflammation and its impact on rehabilitation for patients with non-traumatic haemorrhagic injury (HBI) sequelae has not yet been adequately documented. OBJECTIVE AND METHODS: We therefore considered 31 patients with HBI, to determine the serum levels of inflammatory markers (C-Reactive Protein, CRP and or interleukine-6, IL-6) to establish their impact on functional status (Functional Independence Measure, FIM: 18 indicating the worst performance and 126, a normal score). RESULTS: The results showed an inflammation prevalence (CRP >0.5âmg/dl and/or IL 6 >7 pg/ml) of 74.2% at admission to Rehab. FIM reduction was more pronounced in inflamed compared to non-inflamed subjects (pâ< â0.05) and significantly correlated with blood variables sensitive to inflammation, such as alpha 1 globulin (râ=â- 0.565) and neutrophil/ lymphocyte ratio (râ=â- 0.52), CRP (râ=â- 0.365). At discharge from Rehab, the inflammation rate diminished. Inflamed patients showed similar gains in FIM score as their controls. In the entire population, the FIM gain was significantly associated with a gain in serum albumin, only (râ=â+0.56). CONCLUSIONS: We conclude that systemic inflammation is prevalent in HBI patients and contributes to reduce patient functional status. However, during the Rehab stage, inflammation does not hinder the improvement rate of functional capacity.
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Proteína C-Reativa/metabolismo , Citocinas/sangue , Hemorragias Intracranianas/sangue , Reabilitação Neurológica/estatística & dados numéricos , Idoso , Feminino , Humanos , Hemorragias Intracranianas/epidemiologia , Hemorragias Intracranianas/reabilitação , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND: Systemic inflammation and its impact on rehabilitation for patients with non-traumatic haemorrhagic injury (HBI) sequelae has not yet been adequately documented. OBJECTIVE AND METHODS: We therefore considered 31 patients with HBI, to determine the serum levels of inflammatory markers (C-Reactive Protein, CRP and or interleukine-6, IL-6) to establish their impact on functional status (Functional Independence Measure, FIM: 18 indicating the worst performance and 126, a normal score). RESULTS: The results showed an inflammation prevalence (CRP >0.5âmg/dl and/or IL 6 >7 pg/ml) of 74.2% at admission to Rehab. FIM reduction was more pronounced in inflamed compared to non-inflamed subjects (pâ< â0.05) and significantly correlated with blood variables sensitive to inflammation, such as alpha 1 globulin (râ=â- 0.565) and neutrophil/ lymphocyte ratio (râ=â- 0.52), CRP (râ=â- 0.365). At discharge from Rehab, the inflammation rate diminished. Inflamed patients showed similar gains in FIM score as their controls. In the entire population, the FIM gain was significantly associated with a gain in serum albumin, only (râ=â+0.56). CONCLUSIONS: We conclude that systemic inflammation is prevalent in HBI patients and contributes to reduce patient functional status. However, during the Rehab stage, inflammation does not hinder the improvement rate of functional capacity.
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The goal of this study was to measure arterial amino acid levels in patients with chronic heart failure (CHF), and relate them to left ventricular function and disease severity. Amino acids (AAs) play a crucial role for heart protein-energy metabolism. In heart failure, arterial AAs, which are the major determinant of AA uptake by the myocardium, are rarely measured. Forty-one subjects with clinically stable CHF (New York Heart Association (NYHA) class II to IV) were analyzed. After overnight fasting, blood samples from the radial artery were taken to measure AA concentrations. Calorie (KcalI), protein-, fat-, carbohydrate-intake, resting energy expenditure (REE), total daily energy expenditure (REE × 1.3), and cardiac right catheterization variables were all measured. Eight matched controls were compared for all measurements, with the exception of cardiac catheterization. Compared with controls, CHF patients had reduced arterial AA levels, of which both their number and reduced rates are related to Heart Failure (HF) severity. Arterial aspartic acid correlated with stroke volume index (r = 0.6263; p < 0.0001) and cardiac index (r = 0.4243; p = 0.0028). The value of arterial aspartic acid (µmol/L) multiplied by the cardiac index was associated with left ventricular ejection fraction (r = 0.3765; p = 0.0076). All NYHA groups had adequate protein intake (≥1.1 g/kg/day) and inadequate calorie intake (KcalI < REE × 1.3) was found only in class IV patients. This study showed that CHF patients had reduced arterial AA levels directly related to clinical disease severity and left ventricular dysfunction.
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Aminoácidos/sangue , Metabolismo Energético , Insuficiência Cardíaca/sangue , Miocárdio/metabolismo , Idoso , Estudos de Casos e Controles , Doença Crônica , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Índice de Gravidade de Doença , Função Ventricular EsquerdaRESUMO
Essential amino acids (EAAs) are nutritional substrates that promote body protein synthesis; thus we hypothesised that their supplementation may improve circulating albumin (Alb) and haemoglobin (Hb) in rehabilitative elderly patients following hip fractures (HF). Out of the 145 HF patients originally enrolled in our study, 112 completed the protocol. These subjects were divided into two randomised groups, each containing 56 patients. For a period of two months, one group (age 81.4 ± 8.1 years; male/female 27/29) received a placebo, and the other (age 83.1 ± 7.5 years; male/female 25/31) received 4 + 4 g/day oral EAAs. At admission, the prevalence of both hypoAlb (<3.5 g/dL) and hypoHb (<13 g/dL male, <12 g/dL female) was similar in the placebo group (64.3% hypoAlb, 66% hypoHb) and the treated group of patients (73.2% hypoAlb, 67.8% hypoHb). At discharge, however, the prevalence of hypoAlb had reduced more in EAAs than in placebo subjects (31.7% in EAAs vs. 77.8% in placebo; p < 0.001). There was a 34.2% reduction of anaemia in hypoHb in EAA subjects and 18.9% in placebo subjects, but the difference was not statistically significant. Oral supplementation of EAAs improves hypoAlb and, to a lesser extent, Hb in elderly rehabilitative subjects with hip fractures. Anaemia was reduced in more than one third of patients, which, despite not being statistically significant, may be clinically relevant.
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Aminoácidos Essenciais/administração & dosagem , Suplementos Nutricionais , Hemoglobinas/metabolismo , Fraturas do Quadril/tratamento farmacológico , Inflamação/tratamento farmacológico , Albumina Sérica/metabolismo , Idoso , Idoso de 80 Anos ou mais , Anemia Ferropriva/tratamento farmacológico , Caseínas/administração & dosagem , Dieta , Feminino , Humanos , Masculino , Resultado do TratamentoRESUMO
This investigation compares the levels of plasma kinetics of plasma essential amino acids (EAAs) after ingestion as free-form EAAs (FEAAs) or EAAs as components of dietary protein (DPEAAs), in eighteen healthy individuals, nine elderly (85 ± 6.7 years; 4 male) and nine young (28.7 ± 7 years; 3 males). For two consecutive days, each subject ingested EAAs in the form of (FEAAs) or (DPEAAs) in a random alternate pattern. Five minutes before EAA ingestion (baseline) and 30, 60, 90, 150 and 270 min after, venous blood samples were taken to determine the concentrations of EAAS (micromol/L). In both groups, ingested FEAAs compared to DPEAAs led to faster increase in plasma EAA levels at 30-150 min (p < 0.0001). Moreover, the increased plasma EAAs disappeared faster after FEAA compared to DPEAA. These results may be important in those subjects who have high requirement both for EAAs substrates and anabolic efficiency.
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Aminoácidos Essenciais/sangue , Proteínas Alimentares/sangue , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Aminoácidos Essenciais/farmacocinética , Proteínas Alimentares/farmacocinética , Ingestão de Alimentos , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Cardiac chamber collapse secondary to extrapericardial causes is rare. Focused cardiac ultrasound (FoCUS) in the emergency department can rapidly yield important clinical information and guide management in patients presenting with dyspnea, hypotension, or other cardiopulmonary complaints of uncertain etiology. We report a case of newly-diagnosed cirrhosis with massive ascites and large pleural effusions that distorted normal cardiac anatomy and venous return, in which FoCUS was essential in differentiating underlying pathology of this sick patient and guiding therapy.
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Embolia/diagnóstico por imagem , Corpos Estranhos/diagnóstico por imagem , Dor Lombar/etiologia , Mercúrio/efeitos adversos , Veia Porta/diagnóstico por imagem , Tela Subcutânea/diagnóstico por imagem , Embolia/etiologia , Feminino , Corpos Estranhos/complicações , Humanos , Pessoa de Meia-Idade , Agulhas , RadiografiaRESUMO
Bladder overactivity (OAB) is a multifactorial bladder disorder that requires therapeutics superior to the current pharmacological treatment with muscarinic antagonists. ß3-adrenoceptor (ß3-ADR) agonists represent a novel promising approach that differently addresses the parasympathetic pathway, but the clinical efficacy of these drugs has not been fully elucidated to date. Therefore, we aimed to study the pharmacological mechanisms activated by ß3-ADR agonists at muscular and neural sites in the isolated human bladder. Detrusor smooth muscle strips obtained from male patients undergoing total cystectomy were labelled with tritiated choline and stimulated with electrical field stimulation (EFS). EFS produced smooth muscle contraction and simultaneous acetylcholine ([(3)H]-ACh) release, which mostly reflects the neural origin of acetylcholine. Isoprenaline (INA), BRL37344 and mirabegron inhibited the EFS-evoked contraction and [(3)H]-ACh release in a concentration-dependent manner, yielding concentration-response curves (CRCs) that were shifted to the right by the selective ß3-ADR antagonists L-748,337 and SR59230A. Based on the agonist potency estimates (pEC50) and apparent affinities (pKb) of antagonists evaluated from the CRCs of agonists, our data confirm the occurrence of ß3-ADRs at muscle sites. Moreover, our data are consistent with the presence of inhibitory ß3-ADRs that are functionally expressed at the neural site. Taken together, these findings elucidate the mechanisms activated by ß3-ADR agonists because neural ß3-ADRs participate in the inhibition of detrusor motor drive by reducing the amount of acetylcholine involved in the cholinergic pathway.
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Acetilcolina/metabolismo , Agonistas de Receptores Adrenérgicos beta 3/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/fisiologia , Receptores Adrenérgicos beta 3/metabolismo , Bexiga Urinária/fisiologia , Acetanilidas/antagonistas & inibidores , Acetanilidas/farmacologia , Aminofenóis/farmacologia , Relação Dose-Resposta a Droga , Estimulação Elétrica , Etanolaminas/antagonistas & inibidores , Etanolaminas/farmacologia , Humanos , Isoproterenol/antagonistas & inibidores , Isoproterenol/farmacologia , Masculino , Músculo Liso/efeitos dos fármacos , Propanolaminas/farmacologia , Sulfonamidas/farmacologia , Tiazóis/antagonistas & inibidores , Tiazóis/farmacologia , Bexiga Urinária/efeitos dos fármacosRESUMO
BACKGROUND: Inferior vena cava (IVC) filter placement is performed to mitigate the risk of pulmonary embolism (PE) when anticoagulation is contraindicated or ineffective. Technical advances now allow catheter-based filter retrieval. Many believe the benefits of retrieval are self-evident, yet retrieval carries an inherent complication risk and cost. The purpose of this study was to quantitatively weigh the risks and benefits of IVC filter retrieval using formal decision analysis. METHODS: A Markov state-transition model was used to simulate two clinical scenarios: to leave a previously placed IVC filter or to retrieve it. Analysis was performed during the lifetime of the individual, and outcomes were expressed in quality-adjusted life-years (QALYs). The base case is a 60-year-old man with a filter placed within 3 months who no longer requires mechanical thromboprophylaxis. Potential events included PE, filter complications, and death from all other causes during each cycle. Tolls were used to incorporate the disutility of short-term treatment for PE and filter complications. For the base case and sensitivity analyses, we used utilities and probabilities derived from the literature. RESULTS: In the base case scenario, leaving the filter in place was preferred to filter retrieval, yielding 22.3 vs 21.9 QALYs. One-way sensitivity analysis demonstrated that filter retrieval may be preferable if the utility of living with a filter is <0.98. For all probabilities of retrieval and PE mortality, leaving the filter in place is preferred. CONCLUSIONS: Leaving a previously placed IVC filter provides a 0.4 QALY benefit over retrieving the filter for the average patient. This decision is sensitive to the utility of living with the IVC filter.
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Remoção de Dispositivo , Filtros de Veia Cava , Custos e Análise de Custo , Remoção de Dispositivo/efeitos adversos , Remoção de Dispositivo/economia , Humanos , Masculino , Embolia Pulmonar/fisiopatologia , Embolia Pulmonar/prevenção & controle , Anos de Vida Ajustados por Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento , Filtros de Veia Cava/efeitos adversos , Filtros de Veia Cava/economia , Veia Cava Inferior/patologia , Trombose Venosa/terapiaRESUMO
OBJECTIVES: Muscle release of the amino acid 3-methyl-histidine (3MH) is a sensitive index of myofibrillar protein overdegradation (MPO). We hypothesized that patients with chronic heart failure (CHF) could have increased muscle release of 3MH, which in turn reflects MPO, and that serum electrolyte sodium (Na(+)) and potassium (K(+)) levels may be associated with this 3MH muscle release. METHODS: Thirty-one overweight outpatients (body mass index, 27 ± 4.4 kg/m(2); 22 men and 9 women; age, 56 ± 8.7 y) with clinically stable CHF were studied. After a 24-hour meat-free diet and overnight fasting, patients underwent blood sampling from a cannulated arm vein (V) and concomitantly from the arterial artery (A) to determine plasma 3MH levels and to calculate the A-V difference. Serum levels of Na(+) and K(+) in the venous blood were determined, and the Na(+)/K(+) ratio was calculated. Ten healthy subjects who were matched for gender, age, and body mass index served as controls and underwent the same protocol as the patients with CHF. RESULTS: The patient group had higher arterial (P = 0.02) and venous (P = 0.005) 3MH levels but a similar A-V 3MH difference (P = 0.28) as compared with the controls. Within the CHF group, 67.7% of patients released 3MH, which resulted in a negative A-V value (P < 0.02 as compared with controls). In patients with CHF, the A-V 3MH difference correlated positively with the serum K(+) level (r = 0.62; P = 0.0002) and negatively with Na(+)/K(+) ratio (r = -0.55; P = 0.002). No association was found between the A-V 3MH difference and the Na(+) level. CONCLUSIONS: The study demonstrated the existence of MPO in resting overweight patients with CHF, thereby suggesting that low serum levels of K(+) may contribute to MPO.
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Insuficiência Cardíaca/complicações , Metilistidinas/metabolismo , Proteínas Musculares/metabolismo , Miofibrilas/metabolismo , Obesidade/metabolismo , Potássio/sangue , Artérias/metabolismo , Estudos de Casos e Controles , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/complicações , Sódio/sangue , Veias/metabolismoRESUMO
The purpose of this study was to investigate whether the documented difficulties of physiological amounts of essential amino acids (EAAs) (7 g) to induce protein synthesis could be reflected in a simple method adaptable to a clinical setting. Sixteen healthy individuals, nine elderly (75.3 ± 3.5 years), and seven young (28 ± 2.5 years) were enrolled in the study. Five minutes before EAA ingestion (baseline) and 20, 40, 60, 90, 120, 180 min after EAA ingestion, venous blood samples were taken from the ante-cubital vein to determine the concentrations of EAAs (µmol/L). The results show that plasma EAA increases were significantly higher in old than in young persons at the considered time points (from p < 0.004 to p < 0.001) (unpaired Student t test). However, the velocity rate of the increasing was slower in old subjects than in young group. The study shows that EAAs ingestion by old subject is associated with reduced muscle EAA uptake.
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Envelhecimento/sangue , Aminoácidos Essenciais/sangue , Aminoácidos Essenciais/farmacocinética , Adulto , Fatores Etários , Idoso , Envelhecimento/metabolismo , Velocidade do Fluxo Sanguíneo/fisiologia , Ingestão de Alimentos/fisiologia , Feminino , Humanos , Masculino , Músculo Esquelético/fisiologiaRESUMO
Various forms of low urinary tract symptoms (LUTS) seem dependant upon dysregulation of the purinergic pathway which produces sensory- or motor-activated incontinence. A body of evidence in human urinary bladders supports a link between up-regulation of purinergic activity and the pathogenesis of detrusor instability. This study investigated the potential role of adenosine 5'-triphosphate (ATP) in the control of detrusor motor drive in a model of porcine urinary bladder. The involvement of ATP on excitatory activity was assessed by measuring neurally-evoked [(3)H]-acetylcholine (ACh) release and smooth muscle contraction in detrusor strips. Epithelium-deprived preparations were used to minimize the influence of non-neural sources of ACh and ATP on parasympathetic neurotransmission. ACh release and smooth muscle contractility were not significantly affected by neural ATP in normal detrusor, but markedly enhanced when ATP hydrolysis was reduced by ectoATPase inhibitors, as well as by α,ß-methylene-ATP (ABMA), agonist resistant to ecto-enzymes degradation. Prejunctional P2X receptors located on cholinergic nerves are involved in such potentiating effect. These purinergic heteroreceptors were characterized as P2X(3) subunits by means of the putative antagonists: NF449 (P2X(1,3) selective), NF023 (P2X(1,3) selective), PPNDS (P2X(1) selective) and A-317491 (P2X(3) selective). In porcine detrusor, P2X(3) receptors are functionally expressed at neural site facilitating neurogenic ACh release. When purine breakdown is experimentally down-regulated to mimicking the impaired purinergic pathway observed in pathological human bladders, endogenous ATP can markedly enhance detrusor contractility through activation of these receptors. Since P2X(3) blockade represents a potential therapeutic approach for diseases of the urinary tract, isolated porcine detrusor represents a reliable model for development of novel selective P2X(3) antagonists beneficial in the treatment of detrusor hyperactivity.
Assuntos
Trifosfato de Adenosina/metabolismo , Neurônios Motores/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Sistema Nervoso Parassimpático/efeitos dos fármacos , Antagonistas do Receptor Purinérgico P2X/farmacologia , Receptores Purinérgicos P2X3/efeitos dos fármacos , Bexiga Urinária Hiperativa/tratamento farmacológico , Bexiga Urinária/efeitos dos fármacos , Acetilcolina/metabolismo , Animais , Relação Dose-Resposta a Droga , Estimulação Elétrica , Hidrólise , Técnicas In Vitro , Neurônios Motores/metabolismo , Músculo Liso/inervação , Músculo Liso/metabolismo , Sistema Nervoso Parassimpático/metabolismo , Receptores Purinérgicos P2X3/metabolismo , Suínos , Transmissão Sináptica/efeitos dos fármacos , Fatores de Tempo , Bexiga Urinária/inervação , Bexiga Urinária/metabolismo , Bexiga Urinária Hiperativa/metabolismo , Bexiga Urinária Hiperativa/fisiopatologiaRESUMO
Bladder overactivity (OAB) is a chronic and debilitating lower urinary tract (LUT) disorder that affects millions of individuals worldwide. LUT symptoms associated with OAB, such as urgency and urinary incontinence, cause a hygienic and social concern to patients, but their current pharmacological treatment is largely inadequate due to the lack of uroselectivity. Although OAB etiology remains multifactorial and poorly understood, increasing evidence indicates that serotonin [5-hydroxytryptamine (5-HT)] is an endogenous substance involved in the control of micturition at central and peripheral sites. In this study, we demonstrated the presence of three distinct 5-HT receptors localized at parasympathetic nerve terminals of the human bladder by measuring electrically evoked tritiated acetylcholine release in isolated detrusor strips. These prejunctional receptors, involved in both positive and negative feedback mechanisms regulating cholinergic transmission, have been characterized by means of three highly selective 5-HT antagonists for 5-HT(4), 5-HT(7), and 5-HT(1A) receptors, namely GR113808A ([1-[2-[(-methylsulphonyl) amino] ethyl]4-piperinidyl]methyl1-methyl-1H-indole-3-carboxylate succinate), SB269970 [(R)-3-(2-(2-(4-methylpiperidin-1-yl)ethyl)pyrrolidine-1-sulfonyl)phenol hydrochloride], and WAY100635 [N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridyl)-cyclohexane-carboxamide trichloride]. Under these conditions, we confirmed the facilitatory role of 5-HT(4) heteroreceptors on acetylcholine release and revealed for the first time the occurrence of 5-HT(7) and 5-HT(1A) heteroreceptors with a facilitatory and an inhibitory action, respectively. Our findings strengthen the novel concept for the use of recently patented selective 5-HT agonists and antagonists for the control of OAB dysfunctions associated with inflammatory conditions, although their therapeutic efficacy needs to be explored in the clinical setting.