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BACKGROUND: Grooving evidence suggests that patients could have Direct Access (DA) to physiotherapy. It represents a new model of care, which might lead to improve patients' health status and decrease cost services for healthcare compared with a secondary care referral pathway. The aim of this study is to explore the evidence regarding feasibility, effectiveness, costs, safety and patient satisfaction through DA compared to other organizational models. METHODS: A systematic review was carried out through MEDLINE, CINAHL, and EMBASE databases from their inceptions until March 2018 using keywords related with DA. All articles in English, Italian or Polish comparing the modality of DA with any other organizational modality were included. Two reviewers independently selected eligible studies, extracted the data, and assessed methodological quality using the Newcastle-Ottawa Scale for cohort studies. RESULTS: 1593 articles were initially identified, and thirteen studies met the inclusion criteria. The mean NOS score for study quality was 6.4 ± 1.4 out of a possible total score of nine points. Patients impairments and health care status, were similar through all studies. DA showed less number of physiotherapy treatments, visits to physician, imaging performed and required fewer non-steroidal anti-inflammatory drugs and secondary care. Patients were more satisfied with the service in comparison to the group referred by the physician. and costs per subject were lower. DA patients were younger, with a higher level of education; mostly, they presented a less severe clinical condition and a more acute pathologies related to the spine. No harms were reported. Only one study assessed the clinical safety of the DA. CONCLUSION: The findings suggest that DA to physiotherapy is feasible considering the clinical and economic point of view. However, more research is still needed due to the low evidence of the reviewed studies and to explore the clinical safety of DA.
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Accesibilidad a los Servicios de Salud , Modalidades de Fisioterapia , Humanos , Satisfacción del Paciente , Modalidades de Fisioterapia/economíaRESUMEN
BACKGROUND: The presence of a post-traumatic psychiatric disorder in patients with acute injuries may have adverse effects on outcomes. AIM: In this study our aims were: (1) to assess the frequency of psychiatric disorders after a cerebrovascular accident or traumatic injury requiring rehabilitation; (2) to examine whether there was any correlation between psychiatric disorders and patients' baseline demographic and clinical variables. DESIGN: The study consisted of two phases: the first was cross-sectional and the second prospective with a 12-month follow-up. The period of recruitment was two years. The results of the first phase are presented here. SETTING: The study sample consisted of a consecutive series of patients admitted to hospital because of an acute cerebrovascular accident or a traumatic injury and referred for a rehabilitation program. Two inpatient Rehabilitation Hospitals were involved in the study. POPULATION: The sample consisted of 230 consecutive patients with a recent cerebrovascular accident or trauma included in a rehabilitation program. METHODS: The sample included: 89 men (39%) and 141 women (61%) aged 20-97 years. Psychiatric disorders and motor disabilities were assessed through psychiatric interview and the mini-international neuropsychiatric interview plus (MINI Plus) and, respectively, with the functional independent measure (FIM). In case of post-traumatic stress disorder (PTSD), severity was assessed through the Davidson's Trauma scale. Psychiatric disorders were correlated to demographic and clinical variables through univariate and multivariate analyses, the latter with logistic regression models. RESULTS: The most frequent entry diagnoses were traumatic fracture (41.3%) and stroke (37.0%). Ninety-three patients (40.4%) had one or more psychiatric disturbances at study entry, the commonest being depression (56 cases, 24.7%) and anxiety (23 cases, 10.0%). PTSD was present in 8 cases (3.5%). A history of psychiatric disorder was reported by 55 patients (24.2%) Compared to the rest of the study population, these subjects had more psychopathologic complaints (P<0.001). Mean total FIM score was 54.4 (SD=17.8) and 61.2 (SD=19.6) in patients with and without psychopathology (P<0.01) Independent predictors of psychopathology included past psychiatric history, lower total FIM scores, and limb amputation. Depression was predicted by history of psychiatric disorders and lack of partner. CONCLUSION: History of psychiatric disorders is the most relevant factor associated with psychopathology in patients with an acute cerebrovascular accident or traumatic injury, followed by lower total FIM scores, and type of pathologic event. CLINICAL REHABILITATION IMPACT: The presence of psychiatric disorders may potentially influence the rehabilitation process and outcomes; thus their recognition and management are key factors during a rehabilitation program.
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Trastorno Depresivo/rehabilitación , Traumatismo Múltiple/rehabilitación , Trastornos por Estrés Postraumático/rehabilitación , Rehabilitación de Accidente Cerebrovascular , Heridas y Lesiones/rehabilitación , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Estudios Transversales , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/psicología , Femenino , Estudios de Seguimiento , Hospitalización/estadística & datos numéricos , Humanos , Modelos Logísticos , Masculino , Trastornos Mentales/diagnóstico , Trastornos Mentales/psicología , Trastornos Mentales/rehabilitación , Persona de Mediana Edad , Traumatismo Múltiple/diagnóstico , Traumatismo Múltiple/psicología , Análisis Multivariante , Estudios Prospectivos , Psicometría , Medición de Riesgo , Factores Sexuales , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/psicología , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/psicología , Índices de Gravedad del Trauma , Resultado del Tratamiento , Heridas y Lesiones/diagnóstico , Heridas y Lesiones/psicología , Adulto JovenRESUMEN
A laboratory and on-the-field study was conducted to compare Floor-Based (FB) and Ceiling-Based (CB) patients transfer devices. Pushing and pulling forces were measured by means of computer assisted dynamometer. EMG signals were measured. Standardized patient transfers were setup in the room (bed-chair-door-return). FB devices showed pushing and pulling forces higher than CB ones. CB paths were the smoothest and EMG data related to upper arms and trunk muscles showed stable lower loads for CB. The study suggests that CB patient transfer devices reduced the load. CBs seem the best tools for patient handling.
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Electromiografía , Movimiento y Levantamiento de Pacientes/instrumentación , Transferencia de Pacientes , Fenómenos Biomecánicos , Pisos y Cubiertas de Piso , HumanosRESUMEN
Over the last few years, studies on the relationship between ageing and work have attracted growing interest due to the increased probability among workers of developing major health problems as a consequence of ageing of the working population. Negative outcomes for health are possible when an age-related imbalance appears between physical workload and physical work capacity. Interventions based on workload reductions should help to keep workers on the job for as long as allowed by law. Reference masses by age and sex are suggested by the technical standards of the ISO 11228 series, which are also quoted by Italian law D.Lgs. 81/2008, and EN 1005 series, which recommend limits valid also for manual material handling, and pushing and pulling. Decreasing low back pain prevalence or recurrence, in an ageing population with high prevalence of back disorders, could be more effective than many other approaches to enhance workers' quality of life and consequently maintain and improve workers' performance.
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Salud Laboral , Trabajo , Factores de Edad , Envejecimiento , Humanos , Medicina del Trabajo/normasRESUMEN
PURPOSE: We evaluated the accuracy of magnetic resonance imaging (MRI) in young women with primary amenorrhoea with suspected Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome (congenital absence of both vagina and uterus and presence of normal ovaries). MATERIALS AND METHODS: Fifty-eight women (age range 14-30 years, mean 20.9) with primary amenorrhea were studied with MRI performed with a 1.0-T superconducting magnet (Philips NT Intera). All patients were examined in the supine position using a phased-array coil (four channels). Turbo spin-echo T2-weighted images were acquired in the sagittal, axial and coronal planes with the following parameters: TR 4,750-6,686, TE 100-120, FOV 350-375, 4- to 5-mm sections with a 0.4- to 0.5-mm intersection gap and NSA 6. T1-weighted images were acquired in the axial and coronal planes (TR 470, TE 15, FOV 350, 4-mm sections with a 0.6-mm intersection gap, NSA 3). Two experienced radiologists evaluated all the examinations in consensus to assess the presence, position and morphology of vagina, uterus, ovaries and kidneys and any pelvic abnormalities. MRI results were judged on the basis of laparoscopic findings in 41 patients. RESULTS: MRKH syndrome was confirmed in 56 patients with 100% sensitivity and specificity. MRI identified bilateral Müllerian buds in 34/56 (61%) and unilateral in 10/56 (18%) patients. MRI sensitivity was 81.42%, and there was good agreement with laparoscopy (k=0.55) and full agreement in the identification of cavitation between MRI and intraoperative sonography. Both ovaries were visualised in 54 patients, with regular morphology in 46 (82.1%), polycystic in 10 (17.8%), pelvic in 47 (83.6%) and extrapelvic in eight (14.5%). We found associated abnormalities of the upper urinary tract in six patients (solitary kidney in four and ptosis in two). CONCLUSIONS: MRI is a useful diagnostic tool in the preoperative evaluation of MRKH syndrome and is less expensive and invasive than laparoscopy. Strong cooperation between radiologists and surgeons is highly recommended.
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Anomalías Múltiples/diagnóstico , Imagen por Resonancia Magnética/métodos , Útero/anomalías , Vagina/anomalías , Anomalías Múltiples/cirugía , Adolescente , Adulto , Femenino , Humanos , Cuidados Preoperatorios , SíndromeRESUMEN
Our aims were to assess diagnostic performance of T2-weighted (T2W) and dynamic gadolinium-enhanced T1-weighted (T1W) magnetic resonance imaging (MRI) in the preoperative assessment of myometrial and cervical invasion by endometrial carcinoma and to identify imaging features that predict nodal metastases. Two radiologists retrospectively reviewed MR images of 96 patients with endometrial carcinoma. Tumor size, depth of myometrial and cervical invasion, and nodal enlargement were recorded and then correlated with histology. The sensitivity, specificity, positive and negative predictive values (PPV and NPV) for the identification of any myometrial invasion (superficial or deep) were 0.94, 0.50, 0.93, 0.55 on T2W and 0.92, 0.50, 0.92, 0.50 on dynamic T1W, and for deep myometrial invasion were 0.84, 0.78, 0.65, 0.91 on T2W and 0.72, 0.88, 0.72, 0.88 on dynamic T1W. The sensitivity, specificity, PPV and NPV for any cervical invasion (endocervical or stromal) were 0.65, 0.87, 0.57, 0.90 on T2W and 0.50, 0.90, 0.46, 0.92 on dynamic T1W, and for cervical stromal involvement were 0.69, 0.95, 0.69, 0.95 on T2W and 0.50, 0.96, 0.57, 0.95 on dynamic T1W. Leiomyoma or adenomyosis were seen in 73% of misdiagnosed cases. Sensitivity and specificity for the detection of nodal metastases was 66% and 73%, respectively. Fifty percent of patients with cervical invasion on MRI had nodal metastases. In conclusion, MRI has a high sensitivity for detecting myometrial invasion and a high NPV for deep invasion. MRI has a high specificity and NPV for detecting cervical invasion. Dynamic enhancement did not improve diagnostic performance. MRI may allow accurate categorization of cases into low- or high-risk groups ensuring suitable extent of surgery and adjuvant therapy.
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Neoplasias Endometriales/patología , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Ganglios Linfáticos/patología , Metástasis Linfática , Persona de Mediana Edad , Invasividad Neoplásica , Reproducibilidad de los ResultadosRESUMEN
According to literature up to 85 percent of low back pain (LBP) cannot match a precise pathoanatomical diagnosis, particularly when the association between symptoms and imaging is weak. Effective diagnostic strategy is mainly needed by occupational and rehabilitation medicine. The present study is based on the hypothesis that cumulative effect of repetitive movements and sustained postures, particularly when the movement deviates from the optimal kinesiologic standard, can lead to tissue damage. Therefore this cross-sectional study answers to lack of standardization for LBP diagnosis by means of the classification proposed from Sahrmann within the Movement Impairment Syndromes (MSI) concept. The classification defines 5 categories of LBP: flexion, extension, rotation, extension-rotation and flexion-rotation. The present study results on 84 health workers with LBP match previous published data on the prevalence of MSI categories: 54.8% extension-rotation, 13% flexion-rotation, 11.9% rotation, 3.5% and 16.6% unclassified. MSI could also contribute to better understand LBP severity and the following restricted duty evaluation. Further studies to increase the sample size and to set up randomized clinical trials are needed.
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Dolor de la Región Lumbar/clasificación , Enfermedades Profesionales/clasificación , Adulto , Estudios Transversales , Femenino , Humanos , Dolor de la Región Lumbar/diagnóstico , Masculino , Movimiento , Enfermedades Profesionales/diagnósticoRESUMEN
AIM: To evaluate patterns of disease and identify factors predicting outcome in patients presenting with recurrent endometrial adenocarcinoma following primary surgery. MATERIALS AND METHODS: A retrospective review was performed of the imaging and clinical data in 86 patients (median age 66 years, range 42-88 years) presenting with recurrent endometrial adenocarcinoma following primary surgery. RESULTS: Following primary surgery recurrent disease occurred within 2 years in 64% and within 3 years in 87%. Relapse was seen within lymph nodes in 41 (46%), the vagina in 36 (42%) the peritoneum in 24 (28%) and the lung in 21 (24%). Unusual sites of disease included spleen, pancreas, rectum, muscle and brain. Univariate survival analysis showed the factors significant for poor outcome were: multiple sites of disease, liver and splenic disease, haematogenous, peritoneal and nodal spread, poorly differentiated tumour, and early relapse. The presence of disease within the vagina, bladder or lung was not associated with poor prognosis. Multivariate analysis identified multiple sites of disease, liver and splenic metastases to be independent predictors of poor outcome. CONCLUSION: The most frequently observed sites of relapse are: lymph nodes, vagina, peritoneum and lung. Significant predictors of poor outcome in recurrent disease are multiple sites of disease and liver and splenic metastases.
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Adenocarcinoma/diagnóstico por imagen , Neoplasias Endometriales/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Neoplasias Primarias Múltiples/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Endometriales/cirugía , Femenino , Humanos , Histerectomía , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/secundario , Metástasis Linfática , Persona de Mediana Edad , Análisis Multivariante , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Neoplasias Primarias Múltiples/cirugía , Neoplasias Peritoneales/diagnóstico por imagen , Neoplasias Peritoneales/secundario , Pronóstico , Estudios Retrospectivos , Neoplasias del Bazo/diagnóstico por imagen , Neoplasias del Bazo/secundario , Neoplasias Vaginales/diagnóstico por imagen , Neoplasias Vaginales/secundarioRESUMEN
PURPOSE: To evaluate the results of percutaneous balloon dilation of benign bile duct strictures in a series of patients with a long follow-up period. MATERIAL AND METHODS: 56 patients with benign bile duct strictures underwent balloon catheter dilation. These patients had strictures of various origins: postsurgical, postlocal not surgical treatments, associated with gallstones, due to primary sclerosing cholangitis and to Mirizzi's syndrome. In 41 cases the diagnosis was made on the basis of radiological findings and history and in 15 cases on the basis of transluminal biopsy. RESULTS: In 87.5% of cases the treatment was immediately successful. There were no early recurrences, but 7 (21%) recurrences were seen over 1 year after treatment; of these, 57% underwent another balloon dilation procedure with a positive long-term outcome. CONCLUSION: The long-term success rate obtained in 72% of this series confirms that percutaneous bile duct dilation is a valid alternative to surgery without being burdened by complications; the procedure is also a valid alternative to the approach using endoscopic stents.
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Cateterismo , Colestasis/terapia , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
A case of acute perforation of the small bowel in a 32-year-old man with Crohn's disease not previously diagnosed is presented. The patient underwent an emergency bowel resection and anastomosis and was put on 5-ASA for the following 4 years. No clinical or endoscopic recurrences appeared during this period. In order to avoid both functional disorders and recurrences, a surgical treatment based on resection and anastomosis in minor risk cases, i.e. in patients without abscess and/or concurrent steroid therapy, and on resections limited to grossly involved segments of bowel is advocated.
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Enfermedad de Crohn/complicaciones , Enfermedades del Íleon/etiología , Perforación Intestinal/etiología , Adulto , Anastomosis Quirúrgica , Ciego/cirugía , Estudios de Seguimiento , Humanos , Enfermedades del Íleon/cirugía , Íleon/cirugía , Perforación Intestinal/cirugía , Masculino , Factores de TiempoRESUMEN
Due to its rarity and biochemical and clinical heterogeneity, carnitine deficiency syndrome is difficult to diagnose in those cases where there are no past episodes of the disease. The paper describes two cases: one of a child aged 2 years and 10 months in whom tests permitted the diagnosis of a primary systemic form of carnitine deficiency; the other case concerned a 3 month-old baby girl who died unexpectedly due to hypothesised metabolic disease with secondary carnitine deficiency. The similarities and differences observed in the two cases are discussed.
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Carnitina/deficiencia , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Masculino , Errores Innatos del Metabolismo/diagnóstico , Errores Innatos del Metabolismo/genética , Linaje , SíndromeRESUMEN
Ischaemic colitis is one of the complications following aortic reconstruction for abdominal aortic aneurysm. The diagnosis and monitoring of this complication can be helped by a left colonoscopy. Through an endoscopic valuation of 18 patients, the Authors value the incidence of colonic mucosal or mucosal and muscularis ischaemia following aortic aneurysmectomy with inferior mesenteric arterial ligation.
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Aneurisma de la Aorta/cirugía , Colon/irrigación sanguínea , Colonoscopía , Isquemia/diagnóstico , Anciano , Anciano de 80 o más Años , Aorta Abdominal , Femenino , Estudios de Seguimiento , Humanos , Isquemia/etiología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Factores de TiempoRESUMEN
Adrenergic receptors were identified in healthy human hepatic tissue from thirty-nine subjects undergoing elective abdominal surgery by using the specific alpha 1-antagonist [3H]-prazosin and the beta adrenergic antagonist [3H]-dihydroalprenolol ([3H]-DHA). [3H]-prazosin binding to plasma membranes was rapid, of high affinity, saturable and stereospecific with a maximal binding capacity (Bmax) of 74.1 +/- 5.5 fmol mg-1 of protein. The displacement curve for (-)-norepinephrine was better explained by a one-site binding and after addition of GTP 0.1 mM the curve was not right-shifted, suggesting the majority of alpha receptors in healthy human liver are of the alpha 1 subtype and not linked to a GTP-binding protein. [3H]-DHA binding to liver plasma membranes was also rapid, of high affinity, saturable and stereospecific with a Bmax 96.5 +/- 10.3 fmol mg-1 of protein of receptors. Computer aided analysis of the displacement curve of ICI 118,551, a subtype selective beta 2-antagonist (IC50 = 62 +/- 2 nM), indicated a one-site binding, thus, showing that beta adrenergic receptors are of the beta 2 subtype. The displacement curve of [3H]-DHA for (-)-isoproterenol was right shifted by GTP indicating that beta 2 adrenergic receptors are linked to a GTP-binding protein in human liver. These results indicate that alpha 1- and beta 2-receptors co-exist in human liver but only beta 2-receptors are linked to a GTP-binding protein.
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Hígado/metabolismo , Receptores Adrenérgicos alfa/metabolismo , Receptores Adrenérgicos beta/metabolismo , Membrana Celular/metabolismo , Dihidroalprenolol/metabolismo , Humanos , Cinética , Prazosina/metabolismoRESUMEN
On the assumption that alterations in the adrenergic system may play a role in generating ventricular tachycardia in patients with myocardial post-infarction apical aneurysm, we evaluated norepinephrine concentration, number and affinity of both beta 1 and beta 2 adrenoceptors in perianeurysmatic tissue in twelve patients operated upon for congestive heart failure and recurrent sustained ventricular tachycardia. Concentration of norepinephrine in perianeurysmatic tissue was 0.1 +/- 0.05 micrograms g-1 tissue (n = 8), this value being much lower than that found in papillary muscle (n = 10) from patients with mitral valve stenosis (0.8 +/- 0.02 micrograms g-1 tissue) (P less than 0.01). The total number of beta adrenoceptors (71.4 +/- 7.8 v. 48.0 +/- 5.1 fmol mg-1 protein; P less than 0.01) and the percentage of beta 1 subtype were found to be higher in perianeurysmatic tissue (approximately 90%) than in papillary muscle (approximately 68%). Out of twelve patients with aneurysm, beta 2 adrenoceptors had considerably decreased in three patients and were absent in the remaining nine. Decrease in the neuronally released norepinephrine associated with contrasting behaviours of beta 1 and beta 2 adrenoceptors suggests the presence of a profound alteration in the sympathetic innervation of the perianeurysmatic myocardial tissue that may contribute to the genesis of sustained ventricular tachycardia in patients with postinfarction apical aneurysm.
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Aneurisma Cardíaco/fisiopatología , Infarto del Miocardio/complicaciones , Miocardio/metabolismo , Norepinefrina/metabolismo , Receptores Adrenérgicos beta/fisiología , Taquicardia/etiología , Adulto , Dihidroalprenolol/metabolismo , Femenino , Aneurisma Cardíaco/etiología , Aneurisma Cardíaco/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/metabolismo , Músculos Papilares/metabolismo , Taquicardia/metabolismoRESUMEN
The haemodynamic effect of indenolol, a beta-adrenoceptor blocker with intrinsic sympathomimetic activity (ISA) in animals, has been evaluated in a double-blind cross-over randomized trial after acute (3 days) and long-term treatment (28 days), in 12 hypertensive patients in comparison with that of propranolol. Patients were evaluated at rest and during isometric exercise (hand grip). The overall acute effect of both beta-adrenoceptor blocking drugs was to decrease mean blood pressure, heart rate and cardiac output, while total peripheral resistance increased. In the long-term studies the haemodynamic effect of propranolol was still characterized by cardiodepression and unchanged peripheral resistance. Patients on the long-term treatment with indenolol showed normal cardiac output and reduced total peripheral resistance. The data are compatible with a relatively strong ISA of indenolol, which would be responsible for the haemodynamic pattern observed during chronic treatment.
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Antihipertensivos/uso terapéutico , Hemodinámica/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Indenos/uso terapéutico , Propanolaminas/uso terapéutico , Propranolol/uso terapéutico , Adulto , Presión Sanguínea/efectos de los fármacos , Gasto Cardíaco/efectos de los fármacos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Hipertensión/fisiopatología , Contracción Isométrica , Masculino , Persona de Mediana Edad , Factores de Tiempo , Resistencia Vascular/efectos de los fármacosRESUMEN
To characterize the agonist profile of alpha 2-adrenoceptor agonists (imidazoline-like drugs, azoloazepine derivatives, beta-phenethylamines-like drugs) on human platelets, the characteristics of alpha 2-adrenoceptors (KD, Bmax) have been evaluated and the affinity constants measured by displacement technique and computer-assisted analysis of the curves. Furthermore, since alpha 2-adrenoceptor agonists interact with the post-synaptic receptors in a calcium-operated channel, whether the effect of calcium-entry inhibitors (verapamil, nifedipine, diltiazem) is related to a competition with alpha 2-receptors has also been examined. By Scatchard analysis, it was calculated that in human platelets alpha 2-adrenoceptors have KD = 3.45 nM and Bmax = 247 fmol (mg protein)-1. As far as the potency is concerned, imidazoline-like drugs were the most potent agonists in human platelet alpha 2-adrenoceptors (guanabenz IC50 = 8.6 +/- 0.8 X 10(-8), B-HT 920 IC50 = 2.9 +/- 0.3 X 10(-7), (-)-adrenaline IC50 = 3.4 +/- 0.5 X 10(-7)). Among the calcium-entry inhibitors only verapamil antagonized [3H]rauwolscine binding: the effect was stereospecific, (-)-D 600 being more potent than (+)-D 600. Nifedipine and diltiazem did not affect alpha 2-receptor binding. It is concluded that human platelets alpha 2-receptors share the agonist potency profile of other tissues containing alpha 2-receptors (brain, pre-synaptic junction), and that among calcium-entry blockers only verapamil can antagonize alpha 2-agonists. Nifedipine and diltiazem do not appear to interact stereospecifically with alpha 2-adrenoceptors.
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Azepinas/farmacología , Plaquetas/efectos de los fármacos , Imidazoles/farmacología , Fenetilaminas/farmacología , Receptores Adrenérgicos alfa/metabolismo , Agonistas alfa-Adrenérgicos/metabolismo , Agonistas alfa-Adrenérgicos/farmacología , Adulto , Azepinas/metabolismo , Unión Competitiva , Plaquetas/metabolismo , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Humanos , Imidazoles/metabolismo , Técnicas In Vitro , Cinética , Masculino , Persona de Mediana Edad , Fenetilaminas/metabolismo , Receptores Adrenérgicos alfa/efectos de los fármacos , Estereoisomerismo , Yohimbina/metabolismoRESUMEN
A radioimmunoassay for plasma arginine vasopressin (AVP) has been developed based on R2 antibody of Thomas and Lee, synthetic standard (Ferring) and extraction on Sep-Pak column. High recovery of AVP (approximately 79%) was achieved with a detection limit of 0.25 pg/ml. By improving the technique of measurement of plasma osmolality an intraassay coefficient of variation less than 1% was obtained. Physiological studies performed with this method demonstrated that AVP becomes undetectable after water loading 20 ml per Kg of water po; (N = 6) and increases in response to hypertonic saline infusion (0.05 ml/kg/min; N = 15) with a linear relationship between plasma osmolality and AVP in individual subjects; this relationship is maintained when the test is repeated in the same subjects. However when pooling all data together, the relationship between plasma osmolality and AVP is best expressed by an exponential relationship. This implies that after AVP release is initiated, the concentration of the hormone increases more rapidly than plasma osmolality and the release is continuous possibly due to recruitment of increasing number of neuronal units whose osmotic threshold varies from individual to individual.
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Arginina Vasopresina/metabolismo , Fenómenos Fisiológicos Sanguíneos , Radioinmunoensayo/métodos , Administración Oral , Adulto , Sangre/metabolismo , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Concentración Osmolar , Radioinmunoensayo/normas , Cloruro de Sodio/farmacologíaRESUMEN
To investigate the role of potassium deficiency in the development of glucose intolerance during caloric deprivation, potassium balance was maintained within normality with oral potassium supplementation in a group of obese subjects who underwent protein-modified fast and the results of the study of carbohydrate metabolism (oral glucose test, insulin receptors on monocytes and peripheral glucose utilization as assessed by euglycaemic clamp) were compared with those obtained in a group of obese subjects admitted to protein-modified fast without potassium supplementation. Caloric deprivation without oral potassium supplementation was followed by a negative potassium balance and a decrease of serum potassium levels; a decrease of the peripheral levels of insulin along with an increase in insulin receptors and a striking reduction of peripheral glucose utilization were also observed. The maintenance of normal potassium balance and normal serum potassium levels with oral potassium-chloride supplementation was associated with higher peripheral levels of insulin (P less than 0.01) and improvement of peripheral glucose utilization (P less than 0.01) whereas the binding of insulin to monocytes was unchanged. The data suggest that potassium depletion during protein-modified fast causes a decrease of the peripheral levels of insulin and a resistance to insulin action at the postreceptors sites which is reversed by potassium supply.