RESUMEN
We examined the gender difference in performance of open-water ultra-swimmers crossing the English Channel between 1875 and 2011. A total of 1606 swimmers (1120 males and 486 females) crossed the English Channel within a mean time of 809.6 ± 175.6 min. The overall female swim time of 796.3 ± 188.7 min was not different compared with the overall male swim time of 815.4 ± 169.4 min (P > 0.05). The fastest male swim time ever of 417 min was 6.7% faster than the fastest female swim time ever with 445 min. The gender difference in performance of the top three times ever was 8.9 ± 2.3%. Over the last 36 years, the performance of the annual top three swimmers showed no changes for both females and males. The top three males (564.3 ± 63.8 min) were significantly faster than the top three females (602.1 ± 58.7 min; P < 0.01). The gender difference remained unchanged at 12.5 ± 9.6% over the years. To summarize, the top three male swimmers in the English Channel were â¼12% faster than the females in the last 36 years. It seems unlikely that female open-water ultra-swimmers will overtop males in the near future in the English Channel.
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Rendimiento Atlético/estadística & datos numéricos , Natación/estadística & datos numéricos , Rendimiento Atlético/tendencias , Inglaterra , Femenino , Francia , Humanos , Masculino , Océanos y Mares , Caracteres Sexuales , Factores Sexuales , Natación/fisiología , Natación/tendencias , Factores de TiempoRESUMEN
AIM: The aim of this cross-sectional study was to compare the age-related declines in swimming, cycling, and running and overall race times between males and females in an Olympic distance triathlon, the 'Zürich Triathlon' in Switzerland. METHODS: Swimming (1.5 km), cycling (40 km), running (10 km) and overall race times of 7939 total finishers (1666 females and 6273 males) from 2000 to 2010 in the "Zürich Triathlon" were analysed. RESULTS: There was a significant (P<0.001) age effect on performance for both males and females independently of the discipline. No significant difference in the overall race time was observed between 18 and 34 years for both genders. There was an interaction (P<0.001) of age and gender for swimming, cycling and overall race times, but not for running times. The age-related declines in performance were significantly less pronounced for males compared with females for swimming (>50 years), for cycling (>40 years) and for overall race time (>40 years). CONCLUSION: These data suggest that the age and gender interactions in an Olympic distance triathlon performance differ between the three locomotion modes. Further studies investigating training regimes, competition experience or socio-demographic factors are needed to get a better insight in the phenomenon of the gender specific age-related declines in endurance performance.
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Envejecimiento/fisiología , Atletas , Rendimiento Atlético/fisiología , Adolescente , Adulto , Ciclismo/fisiología , Estudios Transversales , Femenino , Humanos , Masculino , Carrera/fisiología , Factores Sexuales , Natación/fisiología , Adulto JovenRESUMEN
A 49-year-old woman presented with unspecific symptoms including polydipsia, increasing fatigue for several weeks, and vague abdominal pain. Serum calcium (5.30 mmol/l; normal range 2.00-2.60) and parathyroid hormone levels (> 2500.0 ng/l; normal range 15.0-68.0) were extremely elevated. Imaging studies showed a huge mediastinal tumor. Based on these findings a hypercalcemic crisis caused by primary hyperparathyroidism was diagnosed. After intensive care treatment and further diagnostic procedures, the patient's parathyroid adenoma was removed by parathyroidectomy. The postoperative course was uneventful.
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Dolor Abdominal/etiología , Adenoma/complicaciones , Adenoma/diagnóstico , Fatiga/etiología , Neoplasias de las Paratiroides/complicaciones , Neoplasias de las Paratiroides/diagnóstico , Polidipsia/etiología , Dolor Abdominal/diagnóstico , Dolor Abdominal/prevención & control , Adenoma/cirugía , Diagnóstico Diferencial , Fatiga/diagnóstico , Fatiga/prevención & control , Femenino , Humanos , Neoplasias del Mediastino , Persona de Mediana Edad , Neoplasias de las Paratiroides/cirugía , Paratiroidectomía , Polidipsia/diagnóstico , Polidipsia/prevención & control , Resultado del TratamientoRESUMEN
The purposes of this study were (i) to determine the prevalence of exercise-associated hyponatremia (EAH) in multi-stage ultra-marathoners and (ii) to gain more insight into fluid and electrolyte regulation during a multi-stage race. Body mass, sodium concentration ([Naâº]), potassium concentration ([Kâº]), creatinine, urea, specific gravity, and osmolality in urine were measured in 25 male ultra-marathoners in the 'Swiss Jura Marathon' 2008 with 11,000 m gain of altitude over 7 stages covering 350 km, before and after each stage. Haemoglobin, haematocrit, creatinine, urea, [Naâº], [Kâº], and osmolality were measured in plasma before stage 1 and after stages 1, 3, 5, and 7. Two athletes (8%) showed plasma [Naâº] <135 mmol/l. Body mass, plasma [Naâº], and plasma [Kâº] remained unchanged (p>0.05). Urine specific gravity (p<0.001) and osmolality in both plasma (p<0.01) and urine (p<0.001) were increased and haematocrit (p<0.0001), haemoglobin (p<0.0001) and plasma albumin were decreased (p<0.001). Plasma volume (p<0.01) and plasma urea (p<0.001) were increased. The Kâº/Na⺠ratio in urine increased >1.0 after each stage and returned to <1.0 the morning of the next stage (p<0.001). To summarize, more sodium than potassium was excreted during rest. The increased urinary sodium losses during rest are compatible with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) or the cerebral salt-wasting syndrome (CSWS). Further studies are needed to determine the antidiuretic hormone (ADH) and both the atrial natriuretic peptide (ANP) and the brain natriuretic peptide (BNP) during multi-stage races.
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Hiponatremia/etiología , Resistencia Física , Equilibrio Hidroelectrolítico , Adulto , Altitud , Atletas , Humanos , Hiperuricemia/sangre , Hiperuricemia/epidemiología , Hiperuricemia/etiología , Hiperuricemia/orina , Hiponatremia/epidemiología , Hiponatremia/metabolismo , Hiponatremia/fisiopatología , Síndrome de Secreción Inadecuada de ADH/etiología , Masculino , Persona de Mediana Edad , Concentración Osmolar , Potasio/sangre , Potasio/orina , Prevalencia , Carrera , Índice de Severidad de la Enfermedad , Sodio/sangre , Sodio/orina , Gravedad Específica , SuizaRESUMEN
Exercise-associated hyponatremia (EAH) is a well know electrolyte disorder in endurance athletes. Although fluid overload is the most like etiology, recent studies, however, argued whether EAH is a disorder of vasopressin secretion. The aims of the present study were to investigate (i) the prevalence of EAH in male ultra-marathoners and (ii) whether fluid intake, aldosterone or vasopressin, as measured by copeptin, were associated with post-race serum sodium concentration ([Na+]). In 50 male ultra-marathoners in a 100 km ultra-marathon, serum [Na+], aldosterone, copeptin, serum and urine osmolality, and body mass were measured pre- and post-race. Fluid intake, renal function parameters and urine excretion were measured. No athlete developed EAH. Copeptin and aldosterone increased; a significant correlation was found between the change in copeptin and the change in serum [Na+], no correlation was found between aldosterone and serum [Na+]. Serum [Na+] increased by 1.6%; body mass decreased by 1.9 kg. The change in serum [Na+] and body mass correlated significantly and negatively. The fluid intake of ~ 0.58 l/h was positively related to the change in body mass and negatively to both post-race serum [Na+] and the change in serum [Na+]. We conclude that serum [Na+] was maintained by both the mechanisms of fluid intake and the hormonal regulation of vasopressin.
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Aldosterona/metabolismo , Ingestión de Líquidos , Electrólitos/metabolismo , Hiponatremia/metabolismo , Carrera/fisiología , Sodio/sangre , Vasopresinas/metabolismo , Aldosterona/sangre , Atletas , Humanos , Hiponatremia/epidemiología , Hiponatremia/fisiopatología , Masculino , Persona de Mediana Edad , Vasopresinas/sangreRESUMEN
"Low phospholipid associated cholelithiasis" (LPAC) syndrome is an important differential diagnosis in younger patients with biliary symptoms after cholecystectomy and concomitant elevated serum liver tests. Typical symptoms include recurrence of biliary colics after cholecystectomy, echogenic material in the intrahepatic bile ducts, intrahepatic cholestasis of pregnancy or cholestasis under hormonal contraception and a family history of gallstone disease. Patients with LPAC syndrome can be successfully treated with ursodeoxycholic acid.
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Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Enfermedades de los Conductos Biliares/diagnóstico , Conductos Biliares Intrahepáticos , Colecistectomía , Colelitiasis/diagnóstico , Colelitiasis/genética , Pruebas de Función Hepática , Fosfolípidos/deficiencia , Síndrome Poscolecistectomía/diagnóstico , gamma-Glutamiltransferasa/sangre , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Adulto , Alelos , Colangiopancreatografia Retrógrada Endoscópica , Colelitiasis/cirugía , Cólico/etiología , Femenino , Tamización de Portadores Genéticos , Humanos , Linaje , Mutación Puntual/genética , Síndrome Poscolecistectomía/etiología , Síndrome , UltrasonografíaRESUMEN
Melatonin in beeswax was implanted in male weasels (Mustela erminea). Brown weasels and white animals undergoing the spring change to the brown pelage and reproductive activity molted, grew a new white coat, and became reproductively quiescent after treatment. Controls retained or acquired the brown coat and developed or maintained enlarged testes. Treated weasels with pituitary autografts under the kidney capsule grew brown hair after hair growth was initiated by plucking. It is suggested that the pineal gland product, melatonin, initiates changes in the central nervous system and endocrines which result in molting, growth of the white winter pelage, and reproductive quiescence in the weasel.
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Cabello/efectos de los fármacos , Melatonina/farmacología , Pigmentación/efectos de los fármacos , Testículo/efectos de los fármacos , Animales , Carnívoros , Masculino , Hipófisis/trasplante , Trasplante AutólogoRESUMEN
OBJECTIVE: Ursodeoxycholic acid (UDCA) exerts anticholestatic effects in part by protein kinase C (PKC)-dependent mechanisms. Its taurine conjugate, TUDCA, is a cPKC alpha agonist. We tested whether protein kinase A (PKA) might contribute to the anticholestatic action of TUDCA via cooperative cPKC alpha-/PKA-dependent mechanisms in taurolithocholic acid (TLCA)-induced cholestasis. METHODS: In perfused rat liver, bile flow was determined gravimetrically, organic anion secretion spectrophotometrically, lactate dehydrogenase (LDH) release enzymatically, cAMP response-element binding protein (CREB) phosphorylation by immunoblotting, and cAMP by immunoassay. PKC/PKA inhibitors were tested radiochemically. In vitro phosphorylation of the conjugate export pump, Mrp2/Abcc2, was studied in rat hepatocytes and human Hep-G2 hepatoma cells. RESULTS: In livers treated with TLCA (10 micromol/l)+TUDCA (25 micromol/l), combined inhibition of cPKC by the cPKC-selective inhibitor Gö6976 (100 nmol/l) or the non-selective PKC inhibitor staurosporine (10 nmol/l) and of PKA by H89 (100 nmol/l) reduced bile flow by 36% (p<0.05) and 48% (p<0.01), and secretion of the Mrp2/Abcc2 substrate, 2,4-dinitrophenyl-S-glutathione, by 31% (p<0.05) and 41% (p<0.01), respectively; bile flow was unaffected in control livers or livers treated with TUDCA only or TLCA+taurocholic acid. Inhibition of cPKC or PKA alone did not affect the anticholestatic action of TUDCA. Hepatic cAMP levels and CREB phosphorylation as readout of PKA activity were unaffected by the bile acids tested, suggesting a permissive effect of PKA for the anticholestatic action of TUDCA. Rat and human hepatocellular Mrp2 were phosphorylated by phorbol ester pretreatment and recombinant cPKC alpha, nPKC epsilon, and PKA, respectively, in a staurosporine-sensitive manner. CONCLUSION: UDCA conjugates exert their anticholestatic action in bile acid-induced cholestasis in part via cooperative post-translational cPKC alpha-/PKA-dependent mechanisms. Hepatocellular Mrp2 may be one target of bile acid-induced kinase activation.
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Colagogos y Coleréticos/farmacología , Colestasis/tratamiento farmacológico , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Hígado/enzimología , Proteína Quinasa C-alfa/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Ácido Tauroquenodesoxicólico/farmacología , Animales , Colestasis/enzimología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Activación Enzimática , Humanos , Masculino , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Proteína Quinasa C-alfa/metabolismo , RatasRESUMEN
The selection of an appropriate treatment strategy for patients with HCC depends on careful tumor staging and assessment of the underlying liver disease (Fig. 5). All patients with localized HCC (involvement of one single lobe, no vascular invasion or extrahepatic disease) should be evaluated for the potentially curative therapeutic options of partial hepatectomy or OLT. Candidates for partial hepatectomy must have no liver disease or Child's A cirrhosis, normal portal pressure, and normal serum bilirubin. For patients not meeting these criteria, OLT should be considered if there is a solitary lesion smaller than 5 cm in diameter or fewer than three lesions smaller than 3 cm. Local ablative therapies such as PEI, RFA, and TACE offer palliation for patients for whom surgical approaches are contraindicated. Percutaneous alcohol injection and RFA are minimally invasive and can be used on an outpatient basis, usually for tumor nodules smaller than 3 cm. When these therapies are used for small tumors, the survival rates can be similar to those achieved by partial hepatectomy. Transcatheter [figure: see text] arterial chemoembolization may be used as an interim treatment for patients waiting for OLT. Although TACE is often used for the palliation of large tumors, significant survival benefits have not yet been demonstrated for this indication.
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Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/cirugía , Quimioembolización Terapéutica , Etanol/administración & dosificación , Humanos , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/cirugía , Terapia por Radiofrecuencia , Tasa de SupervivenciaRESUMEN
OBJECTIVES: To examine individual clinic staff members' experiences with using an immunization registry and to compare staff members' perceptions of immunization registries across different provider sites. DESIGN: Cross-sectional survey using in-depth interviews and direct observation. SETTINGS: The pediatric department of an urban community health center and 2 urban hospital-based pediatric primary care clinics. PARTICIPANTS: Twenty-five subjects were recruited using maximum variation sampling at each site. The subjects included clerks, clinic assistants, licensed practical nurses, a nurse practitioner, and registered nurses. MAIN OUTCOME MEASURES: Clinic staff members' perceptions of an immunization registry and frequency of registry use. RESULTS: Differences were observed in subjects' perceptions of an immunization registry across provider sites. Although most subjects had positive attitudes toward the registry, they did not necessarily believe that the registry decreased their workload. The ability to access immunization registry data and actual use of the registry seem to be related to training of clinic personnel, location of the registry terminal, and helpfulness and availability of registry staff. CONCLUSION: Obtaining the opinions of immunization registry users is an important strategy to evaluate the usefulness of a registry in a site and target possible areas for improvement.
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Actitud Frente a la Salud , Personal de Salud , Programas de Inmunización/estadística & datos numéricos , Sistema de Registros/estadística & datos numéricos , Encuestas y Cuestionarios , Centros Comunitarios de Salud , Estudios Transversales , Humanos , Evaluación de Necesidades , Atención Primaria de Salud , Carga de TrabajoRESUMEN
OBJECTIVES: To determine appointment failure rates in pediatric resident continuity clinics nationally, and to identify characteristics of clinics with respect to factors that may affect appointment failure rates. DESIGN: A one-page questionnaire administered via facsimile machine to pediatric residencies' continuity clinic directors. RESULTS: Of 200 continuity clinic directors, 160 (80%) returned the survey. The mean no-show percentage was 30.9%, with a range of 3% to 80%. Among the factors studied, only mode of payment emerged as an independent predictor. CONCLUSIONS: Appointment failure is a substantial problem in pediatric resident continuity clinics, which needs attention if resident learning, patient care, and clinic efficiency are to be optimized.
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Citas y Horarios , Atención a la Salud/normas , Pacientes , Pediatría , Humanos , Encuestas y Cuestionarios , Estados UnidosRESUMEN
OBJECTIVE: To investigate the effect on immunization levels of retrospective written feedback to residents regarding missed immunization opportunities. DESIGN: Randomized trial with control group. SETTING: Pediatric resident continuity clinic in an urban hospital-based primary care clinic. PARTICIPANTS: Thirty-two postgraduate level 2 and postgraduate level 3 pediatric residents. INTERVENTION: Monthly retrospective written feedback mailed to residents detailing their missed immunization opportunities and appointment failure rates over a 12-month period beginning in February 1997. MAIN OUTCOME MEASURES: The immunization level of 2-year-old children in the resident clinic was the main outcome of interest. Secondary outcomes included missed immunization opportunity rates and appointment failure rates. RESULTS: Postintervention immunization levels were 71.4% (95% confidence limits [CLs]: 63.2%, 78.7%) for patients from the intervention group and 68.5% (95% CLs: 60.8%, 75.4%) for patients from the control group. The immunization level for patients of both groups who had fewer than 2 visits during the second year of life was 47.2% (95% CLs: 38.2%, 56.3%). This compares with an immunization level of 78.1% (95% CLs: 66.0%, 87.5%) for patients from both groups who had 2 visits during the second year of life, and with an immunization level of 88.2% (95% CLs: 81.0%, 93.4%) for patients of both groups who had more than 2 visits during the second year of life (P<.001). CONCLUSIONS: In this setting, written retrospective feedback to residents was an ineffective strategy for improving immunization levels. Adequate follow-up during the second year of life is critical in achieving high immunization levels.
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Inmunización/estadística & datos numéricos , Internado y Residencia , Servicio Ambulatorio en Hospital/normas , Pediatría/educación , Adulto , Preescolar , Retroalimentación , Femenino , Georgia , Humanos , Masculino , Pautas de la Práctica en Medicina , Servicios Preventivos de SaludRESUMEN
An in vitro autoradiographic study was performed to characterize specific rat brain binding sites for non-opioid neuroleptic-like gamma-type endorphins, using [35S]Met-des-enkephalin-gamma-endorphin ([35S]Met-DE gamma E; [35]S-beta-endorphins(5-17)) with high specific activity as radioligand. The binding sites appeared to be confined to rat forebrain regions, e.g., orbital cortex, frontal cortex, cingulate cortex, piriform cortex, nucleus accumbens, amygdala, mediodorsal nucleus of the thalamus and arcuate and periventricular nuclei of the hypothalamus. These regions are part of the mesocorticolimbic feedback circuit. Densitometric analysis of the autoradiographs revealed that the density of the binding sites was highest in the mediodorsal nucleus of the thalamus and the amygdala. Concentration-dependent displacement of [35S]Met-DE gamma E (500 pM) with DE gamma E yielded an IC50 of 0.6 nM whereas DE alpha E (beta-endorphin(6-16)) had an IC50 of 210 nM. Various endorphins, sharing the gamma-endorphin C terminus, displaced [35S]Met-DE gamma E to the same extent as non-labelled DE gamma E (at 10(-6) M) whereas non-endorphin peptides did not show displacing capacity. Possible relationships of the binding sites with opioid receptors were investigated. DAMGO (mu) and DPDPE (delta) displaced [35S]Met-DE gamma E to some extent at 10(-6) M whereas U69,593 (kappa) was inactive, suggesting that the binding sites for gamma-type endorphins may resemble mu- and delta-opioid receptors in some aspects. Similarly, relationships with dopamine receptors were investigated. Haloperidol partially displaced [35S]Met-DE gamma E whereas sulpiride, SKF38,393 and 3-PPP at 10(-6) M did not induce significant displacement. Thus, binding sites are distinct from dopamine receptors.(ABSTRACT TRUNCATED AT 250 WORDS)
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Encéfalo/metabolismo , Endorfinas/metabolismo , Receptores Opioides/metabolismo , betaendorfina , Amígdala del Cerebelo/metabolismo , Animales , Anticuerpos Monoclonales , Autorradiografía , Unión Competitiva , Cromatografía Líquida de Alta Presión , Densitometría , Masculino , Ratas , Ratas Wistar , Receptores Dopaminérgicos/metabolismo , Relación Estructura-Actividad , Radioisótopos de Azufre , betaendorfina/inmunologíaRESUMEN
INTRODUCTION: The medical and public health communities advocate immunization registries as one tool to achieve national immunization goals. Although substantial resources have been expended to establish registries across the nation, minimal research has been conducted to evaluate provider participation costs. METHODS: The objective of this study was to identify the direct costs to participate in an immunization registry. To estimate labor and equipment costs, we conducted interviews and direct observation at four sites that were participating in one of two immunization registries. We calculated mean data-entry times from direct observation of clinic personnel. RESULTS: The annual cost of participating in a registry varied extremely, ranging from $6083 to $24,246, with the annual cost per patient ranging from $0.65 to $7. 74. Annual per-patient costs were lowest in the site that used an automated data-entry interface. Of the sites requiring a separate data-entry step, costs were lowest for the site participating in the registry that provided more intensive training and had a higher proportion of the target population entered into the registry. CONCLUSIONS: Ease of registry interface, data-entry times, and target population coverage affect provider participation costs. Designing the registry to accept electronic transfers of records and to avoid duplicative data-entry tasks may decrease provider costs.
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Costos Directos de Servicios/estadística & datos numéricos , Programas de Inmunización/economía , Sistema de Registros , Instituciones de Atención Ambulatoria/economía , Servicios de Salud Comunitaria/economía , Costos y Análisis de Costo/estadística & datos numéricos , Procesamiento Automatizado de Datos/economía , Humanos , Estados UnidosRESUMEN
INTRODUCTION: The medical and public health communities advocate the use of immunization registries as one tool to achieve national goals for immunization. Despite the considerable investment of resources into registry development, little information is available about the costs of developing or maintaining a registry. METHODS: The objective of this study was to measure the direct costs of maintaining one immunization registry. Cost and resource-use data were collected by interviewing registry personnel and staff at participating pediatric practices, collecting available financial records, and direct observation. RESULTS: The estimated direct cost for maintaining the registry during the 3 calendar years 1995 through 1997 was $439,232. In 1997, this represented an annual cost of $5.26 per child immunized whose record was entered into the registry. In all years, personnel expenses represented at least three fourths of the total costs, with the majority of administrative effort donated. Yearly costs increased over time largely because of growing administrative personnel requirements as the registry became fully operational. CONCLUSION: Considerable resources are required to establish and maintain immunization registries. Because personnel costs, particularly nontechnical personnel, represent a large portion of total registry costs, it is important to accurately account for donated effort. Recommendations for future registry cost studies include prospective data collection and focusing upon the costs of providing specific outreach or surveillance functions rather than overall registry costs. In addition, registry effectiveness evaluations are needed to translate registry costs into cost-effectiveness ratios.
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Programas de Inmunización/economía , Sistema de Registros/estadística & datos numéricos , Niño , Costos y Análisis de Costo , Recolección de Datos/estadística & datos numéricos , Femenino , Georgia , Humanos , MasculinoRESUMEN
To investigate the significance of endogenous, neuroleptic-like gamma-type endorphins and their putative receptors, polyclonal and monoclonal antibodies against gamma-type endorphins, which may bio-inactivate the ligands for the receptors, and monoclonal anti-idiotype antibodies, which presumably bind to the receptors, were injected into the nucleus accumbens of the rat brain. The desenkephalin-gamma-endorphin-induced antagonism of the hypomotility response elicited by challenge with apomorphine injected into the nucleus accumbens was used as test system. Both the anti-desenkephalin-gamma-endorphin antibodies and anti-idiotype antibodies blocked the action of exogenous desenkephalin-gamma-endorphin. Thus, the anti-idiotype antibodies may serve as receptor antagonists. Chronic treatment (injection into the nucleus accumbens) with the anti-idiotype antibodies induced sustained hypermotility, decreased habituation and impaired passive avoidance behavior. In such treated animals local treatment with apomorphine did not elicit hypomotility. It is suggested that gamma-type endorphins influence the setpoint for feedback regulation in dopaminergic neurons equipped with gamma-type endorphin receptor systems.
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Anticuerpos Monoclonales/farmacología , Conducta Animal/efectos de los fármacos , Receptores Opioides/efectos de los fármacos , gamma-Endorfina/inmunología , Animales , Apomorfina/farmacología , Reacción de Prevención/efectos de los fármacos , Agonistas de Dopamina/farmacología , Retroalimentación/fisiología , Habituación Psicofisiológica/efectos de los fármacos , Masculino , Actividad Motora/efectos de los fármacos , Oxitocina/inmunología , Ratas , Ratas Wistar , Receptores Dopaminérgicos/efectos de los fármacos , Receptores Opioides/inmunologíaRESUMEN
Spiral computer tomography (Sp-CT) was performed on 25 patients with 81 aorto-coronary bypasses, with persistent symptoms, following selective coronary angiography. The purpose was to determine to what extent Sp-CT is able to demonstrate patency or occlusion of individual bypasses. From the raw data, transverse sections and standardised 3D reconstructions were obtained. Statistical evaluation showed a sensitivity of 93% and a specificity of 100% with regard to patency. Sp-CT provides optimal contrast and complete demonstration of the bypass without movement artifacts from respiration. 3D reconstructions aid in the evaluation of complex anatomical situations but occasionally lead to incorrect diagnosis of stenoses or occlusions. Compared with other non-invasive procedures (conventional CT and NMR) Sp-CT has proved significantly better for the evaluation of bypass occlusions. Sp-CT cannot completely replace angiography but in some cases may be an acceptable alternative.
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Puente de Arteria Coronaria , Oclusión de Injerto Vascular/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Anciano , Aortografía/instrumentación , Aortografía/métodos , Angiografía Coronaria/instrumentación , Angiografía Coronaria/métodos , Enfermedad Coronaria/diagnóstico por imagen , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X/instrumentaciónRESUMEN
Contemporary prostheses have developed from small iterations on moderately successful archetypes. This has resulted in modern designs that can either be termed cosmetic or functional, with neither attribute being fully satisfied. A new strategy is needed to develop a generation of upper-limb prostheses that will integrate both cosmetic and functional requirements in a single device. It is hypothesized that design principles applicable to a new generation of prostheses will result from exploring close analogies to the human upper limb. A method of practice led design research has been adopted to explore appropriate analogies, using the production of physical models to elucidate the design problem to the design team and other interested parties. This method uses a consciously iterative approach whereby criticisms and lessons learnt in the development of early models are embodied in subsequent models. This paper describes the first iterative cycle. It includes a critical review of the devices currently available and a study of mechanical analogies to original anatomy which form two of the inputs to the development of a skeletal model hand. It details the lessons learnt from this study and concludes on the wider application of practice led design research in medical engineering.
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Miembros Artificiales/normas , Diseño Asistido por Computadora , Mano/fisiología , Fenómenos Biomecánicos , Ergonomía , Medicina Basada en la Evidencia , Fuerza de la Mano , Humanos , Modelos Anatómicos , Diseño de Prótesis , InvestigaciónRESUMEN
BACKGROUND: In elderly patients with gallstone disease, a gallstone ileus must be considered for unexplained abdominal pain. This is demonstrated in the following case report. CASE REPORT: A 75-year-old female patient presented with a 72-hour history of abdominal pain, nausea and vomiting. The patient's abdomen was mildly distended, although soft and nontender with bowel sounds present. Plain radiographs and ultrasound investigation of the abdomen were compatible with small bowel obstruction. To clarify the etiology, an abdominal computed tomography scan was obtained. These examinations disclosed air in the biliary tree, dilated small bowel and an impacted intraluminal abnormality in the terminal ileum compatible with a gallstone. Operative intervention confirmed the presence of a 3 cm obstructing calculus in the terminal ileum that was removed by an enterolithotomy. A two-step cholecystectomy and closure of the cholecystoduodenal fistula were performed 8 weeks later. The patient's recovery was uneventful. CONCLUSIONS: Although rare in a general population, gallstone ileus accounts for 25% of nonstrangulated small bowel obstructions in patients over the age of 65. The radiographic picture and ultrasound of small bowel obstruction and the presence of air in the biliary tree are suggestive for the diagnosis of a gallstone ileus. In our patient, the computed tomography and ultrasound findings confirmed the diagnosis and led to a prompt and directed surgical intervention. In patients with comorbid factors a two-step approach with enterolithotomy in a first and cholecystectomy in a second operation should be the therapeutic strategy of choice.
Asunto(s)
Dolor Abdominal/etiología , Fístula Biliar/diagnóstico , Colelitiasis/diagnóstico , Enfermedades Duodenales/diagnóstico , Enfermedades de la Vesícula Biliar/diagnóstico , Fístula Intestinal/diagnóstico , Obstrucción Intestinal/diagnóstico , Viaje , Vómitos/etiología , Anciano , Fístula Biliar/cirugía , Colelitiasis/cirugía , Diagnóstico Diferencial , Enfermedades Duodenales/cirugía , Femenino , Enfermedades de la Vesícula Biliar/cirugía , Humanos , Fístula Intestinal/cirugía , Obstrucción Intestinal/cirugía , LaparoscopíaRESUMEN
BACKGROUND AND AIMS: Measurement of 7 alpha-hydroxy-4-cholesten-3-one (C4) in serum is a semiquantitative test for bile acid malabsorption (BAM). We have previously established pediatric normal values for C4 with an upper limit of normal of 66.5 ng/mL, independent of age and sex. Here we performed the C4 test in 58 pediatric patients with Crohn's disease (CD) and ulcerative colitis (UC). METHODS: C4 was measured using high performance liquid chromatography (HPLC) in fasting serum samples of 44 patients with CD (range 7-19 years) and 14 with UC (4-18 years). Disease activity was assessed by the pediatric CD and UC activity indices (PCDAI and PUCAI, respectively) plus serum (CRP, ESR) and fecal inflammatory markers (calprotectin). RESULTS: C4 concentrations were increased in 10 CD (23%) (range: 70.8-269.3 ng/mL) but only one UC patient (72.9 ng/mL). CD patients with diarrhea (n=12) had higher C4-values compared to those without (76.9 vs. 30.4 ng/mL; p=0.0043). Ileal resection in CD patients (n=10) was associated with increased C4 concentrations (81.2 vs. 24.3 ng/mL, p=0.0004). No correlation was found between C4 values and inflammatory markers. Six of 7 CD patients with persistent diarrhea but quiescent disease (PCDAI ≤12.5) had C4 values indicating BAM. CONCLUSION: Elevated C4 concentrations indicating BAM are common in children with CD. They are associated with ileal resection and non-bloody diarrhea in the absence of active disease or elevated inflammatory markers. The C4-test identifies a subgroup of CD patients with persistent diarrhea in spite of clinical remission which may benefit from bile acid binding therapy.