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1.
Infection ; 41(3): 691-4, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22996385

RESUMEN

Human toxocariasis has been reported to cause a broad spectrum of neurological syndromes, including encephalitis, meningitis and meningo-radiculitis. Nevertheless, cerebral infection by Toxocara may go undiagnosed due to its rarity, elusive symptoms and lack of availability of appropriate testing. We report the case of a 54-year-old man who presented with abdominal pain and paralytic ileus approximately 3 weeks after having eaten raw snails (a folk remedy for peptic ulcer). Three weeks later, marked eosinophilia ensued, associated with mental clouding, nystagmus, diplopia, peripheral limbs ataxia, urinary retention, slackened deep tendon reflexes, arthralgias and myalgias. Cerebrospinal fluid (CSF) examination demonstrated an eosinophilic meningitis, and Toxocara canis cerebral infection was diagnosed by positive serology and by the detection of T. canis DNA in the CSF. The patient made a full recovery following treatment with albendazole and corticosteroids. Physicians should be aware of this rare presentation of toxocariasis, whose diagnosis is, today, facilitated by molecular biology techniques. A history of ingestion of raw snails may alert the clinician to consider the possibility of such an uncommon condition.


Asunto(s)
Sistema Nervioso Autónomo/fisiopatología , Encefalitis/complicaciones , Encefalitis/patología , Ileus/etiología , Toxocara canis/aislamiento & purificación , Toxocariasis/complicaciones , Toxocariasis/patología , Animales , Anticuerpos Antihelmínticos/líquido cefalorraquídeo , Líquido Cefalorraquídeo/citología , ADN de Helmintos/líquido cefalorraquídeo , Encefalitis/parasitología , Enfermedades Transmitidas por los Alimentos/etiología , Enfermedades Transmitidas por los Alimentos/parasitología , Enfermedades Transmitidas por los Alimentos/patología , Humanos , Ileus/parasitología , Ileus/patología , Masculino , Persona de Mediana Edad , Toxocara canis/genética , Toxocara canis/inmunología , Toxocariasis/parasitología
2.
bioRxiv ; 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37786678

RESUMEN

The default mode network (DMN) is a widely distributed, intrinsic brain network thought to play a crucial role in internally-directed cognition. It subserves self-referential thinking, recollection of the past, mind wandering, and creativity. Knowledge about the electrophysiology underlying DMN activity is scarce, due to the difficulty to simultaneously record from multiple distant cortical areas with commonly-used techniques. The present study employs stereo-electroencephalography depth electrodes in 13 human patients undergoing monitoring for epilepsy, obtaining high spatiotemporal resolution neural recordings across multiple canonical DMN regions. Our results offer a rare insight into the temporal evolution and spatial origin of theta (4-8Hz) and gamma signals (30-70Hz) during two DMN-associated higher cognitive functions: mind-wandering and alternate uses. During the performance of these tasks, DMN activity is defined by a specific pattern of decreased theta coupled with increased gamma power. Critically, creativity and mind wandering engage the DMN with different dynamics: creativity recruits the DMN strongly during the covert search of ideas, while mind wandering displays the strongest modulation of DMN during the later recall of the train of thoughts. Theta band power modulations, predominantly occurring during mind wandering, do not show a predominant spatial origin within the DMN. In contrast, gamma power effects were similar for mind wandering and creativity and more strongly associated to lateral temporal nodes. Interfering with DMN activity through direct cortical stimulation within several DMN nodes caused a decrease in creativity, specifically reducing the originality of the alternate uses, without affecting creative fluency or mind wandering. These results suggest that DMN activity is flexibly modulated as a function of specific cognitive processes and supports its causal role in creative thinking. Our findings shed light on the neural constructs supporting creative cognition and provide causal evidence for the role of DMN in the generation of original connections among concepts.

3.
medRxiv ; 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37986996

RESUMEN

A reliable physiological biomarker for Major Depressive Disorder (MDD) is necessary to improve treatment success rates by shoring up variability in outcome measures. In this study, we establish a passive biomarker that tracks with changes in mood on the order of minutes to hours. We record from intracranial electrodes implanted deep in the brain - a surgical setting providing exquisite temporal and spatial sensitivity to detect this relationship in a difficult-to-measure brain area, the ventromedial prefrontal cortex (VMPFC). The aperiodic slope of the power spectral density captures the balance of activity across all frequency bands and is construed as a putative proxy for excitatory/inhibitory balance in the brain. This study demonstrates how shifts in aperiodic slope correlate with depression severity in a clinical trial of deep brain stimulation for treatment-resistant depression (TRD). The correlation between depression severity scores and aperiodic slope is significant in N=5 subjects, indicating that flatter (less negative) slopes correspond to reduced depression severity, especially in the ventromedial prefrontal cortex. This biomarker offers a new way to track patient response to MDD treatment, facilitating individualized therapies in both intracranial and non-invasive monitoring scenarios.

4.
Diabetes Metab Res Rev ; 27(3): 262-8, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21309049

RESUMEN

AIMS: Since glucose levels during oral glucose tolerance test (OGTT) are determined both by insulin sensitivity and insulin secretion, we investigated whether the percentage increment (PG%) of 2-h plasma glucose (2hPG) over fasting plasma glucose (FPG) is related to validated indexes of insulin sensitivity and insulin secretion. METHODS: Using Stumvoll's formulas we calculated estimated insulin sensitivity index and first-phase insulin secretion in 1281 subjects who underwent a standard OGTT. The ratio first-phase insulin secretion/(1/estimated insulin sensitivity index) was considered a surrogate index of ß-cell function. For each subject we calculated PG% using the formula: [(2hPG - FPG)/FPG] × 100. For each glucose tolerance group we formed tertiles based on PG% values. RESULTS: In each glucose tolerance group, ß-cell function was better preserved in lower PG% tertiles, demonstrating a correlation between PG% and insulin resistance. CONCLUSIONS: By a simple calculation, our study allows, expansion of the clinical use of OGTT to recognize subjects liable to further worsening of glucose homeostasis, independent from glucose tolerance groupings.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Ayuno/sangre , Prueba de Tolerancia a la Glucosa , Células Secretoras de Insulina/fisiología , Diabetes Mellitus Tipo 2/etiología , Humanos , Insulina/sangre , Insulina/metabolismo , Resistencia a la Insulina , Secreción de Insulina
5.
Nutr Metab Cardiovasc Dis ; 21(6): 406-11, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20171854

RESUMEN

BACKGROUND AND AIMS: Cardiovascular (CV) events occur even when LDL-C are <100mg/dL. To improve the detection of CV risk we investigated the apoB/apoA-I ratio versus LDL-C in subjects considered normal glucose tolerant (NGT) by oral glucose tolerance test (OGTT). METHODS AND RESULTS: We enrolled 616 NGT (273 men and 343 women), and we measured insulin resistance, lipid profile, apoB/apoA-I and the factors compounding the metabolic syndrome (MetS). An unfavourable apoB/apoA-I (≥0.9 for males and ≥0.8 for females) was present in 13.9% of 108 patients with LDL-C <100mg/dL: compared to subjects with lower apoB/apoA-I (<0.9 for males and <0.8 for females), they had more elements of MetS and their lipid profile strongly correlated with high CV risk. Out of 314 patients with lower apoB/apoA-I, 40.12% had LDL-C ≥130mg/dL: these retained a more favourable lipid profile than corresponding subjects with elevated apoB/apoA-I ratio. Finally, we found a significant correlation between LDL-C and apoB/apoA-I ratio (r=0.48, p<0.0001). CONCLUSIONS: In NGT with LDL-C <100mg/dL, a higher apoB/apoA-I exhibited an atherogenic lipid profile, indicating that LDL-C alone is insufficient to define CV risk. Independent from LDL-level, when apoB/apoA-I is lower, the lipid profile is, in fact, less atherogenic. This study demonstrates that apoB/apoA-I is at least complementary to LDL-C in identifying the "effective" CV risk profile of asymptomatic NGT subjects.


Asunto(s)
Apolipoproteína A-I/sangre , Apolipoproteínas B/sangre , Enfermedades Cardiovasculares/diagnóstico , LDL-Colesterol/sangre , Adulto , Glucemia/análisis , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/patología , Estudios de Cohortes , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Resistencia a la Insulina , Masculino , Síndrome Metabólico/sangre , Persona de Mediana Edad , Factores de Riesgo
6.
Nephron Physiol ; 117(1): p1-10, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-20798556

RESUMEN

BACKGROUND AND AIMS: The presence of altered plasma Na concentration (PNa) allows calculations of changes in water and electrolyte contents, which are not feasible during normonatremic derangements. We have developed a computational algorithm whereby the changes in solute (ΔNa and ΔCl) and solvent (ΔV) contents can be computed exactly when Na is lost entirely as NaCl (or NaHCO(3)) and nearly exactly in all other circumstances, except when the losses of Na and Cl occur in the same proportions as those of the normal plasma concentration of these ions. METHODS: In computer experiments, we simulated different fluid depletions containing 140 mEq/l of Na (which is to say, ΔNa/ΔV ≈ 140), coupled with variable ratios in Na to Cl losses (variable ΔNa/ΔCl). The data were back-calculated with our algorithms from the ensuing plasma ion concentrations (PNa(1), PCl(1) and POAN(1), where subscript (0) and (1) indicate normal and deranged plasma concentration values, respectively, and OAN indicates anions other than Cl), as if they had been measured on patients, and from known normal values (TBW(0), ECV(0), Na(0)). These were compared to the true values used to build the simulations. This procedure was reproduced in 17 patients suffering from iso-osmolar dehydration, where true data were obtained by balance studies. RESULTS: True and calculated data were compared with linear regression analysis. We obtained significant correlations both in computer-simulated and real patients (R(2) = 0.83, p < 0.005 and R(2) = 0.63, p < 0.05, respectively). CONCLUSION: This new math model and its related computational method are useful in the correct evaluation and treatment of iso-osmolar dehydration.


Asunto(s)
Algoritmos , Agua Corporal/metabolismo , Deshidratación/diagnóstico , Hiponatremia/diagnóstico , Pruebas de Función Renal/métodos , Modelos Biológicos , Sodio/sangre , Simulación por Computador , Deshidratación/sangre , Diagnóstico por Computador/métodos , Femenino , Humanos , Hiponatremia/sangre , Masculino , Concentración Osmolar , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Equilibrio Hidroelectrolítico
7.
Gastroenterol Clin Biol ; 34(4-5): 305-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20627637

RESUMEN

We report a series of ten cases of the clinical, endoscopic and pathological features of gastric metastases. Patients were six women and four men between 54 and 88 years old, with gastric metastases from breast carcinoma (4), lung carcinoma (4) and melanoma (2). Patients underwent an upper gastrointestinal endoscopy for epigastralgia (2), hematemesis (2), dysphagia (1) and anemia (5). On endoscopy, tumors appeared as nodules with a central ulceration (5), an ulceration (4) or simulating linitis plastica (1). Metastases were located in the cardia (2), fundus (5) and antrum (3). Primary tumors had been diagnosed between one day and 20 years before upper endoscopy. Eight patients had multivisceral metastases. The microscopic features of the gastric metastases resembled a primary gastric cancer in eight cases. Thanks to clinical data, the pathologist confirmed the diagnosis of gastric metastases on immunohistochemistry. Nine patients died in the eight-month follow-up period. Gastric metastases are rare, occur at a late stage of the neoplastic disease, and have a poor prognosis. Diagnosis of gastric metastases is difficult because they simulate primary gastric cancer on endoscopy and on microscopic examination. A correct diagnosis is based on good communication between gastroenterologists and pathologists.


Asunto(s)
Endoscopía Gastrointestinal , Neoplasias Gástricas/patología , Neoplasias Gástricas/secundario , Adenocarcinoma/patología , Adenocarcinoma/secundario , Anciano , Anciano de 80 o más Años , Carcinoma Lobular/patología , Carcinoma Lobular/secundario , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
8.
Gastroenterol Clin Biol ; 34(1): 100-3, 2010 Jan.
Artículo en Francés | MEDLINE | ID: mdl-20056367

RESUMEN

We report a case of recurrent digestive haemorrhage due to bleeding ectopic jejunal varices complicating portal hypertension in a 51-year-old cirrhotic patient, treated 1 year ago by transjugular intrahepatic porto-systemic shunt (TIPS) for the same problem. Successful embolisation with coils, of ectopic varices, was performed using original transjugular and trans-TIPS route, without complication, and no recurrence during a follow-up of 24 months.


Asunto(s)
Embolización Terapéutica , Várices Esofágicas y Gástricas/terapia , Hemorragia Gastrointestinal/terapia , Várices Esofágicas y Gástricas/complicaciones , Femenino , Hemorragia Gastrointestinal/etiología , Humanos , Cirrosis Hepática/complicaciones , Persona de Mediana Edad , Recurrencia
9.
Colorectal Dis ; 11(2): 178-83, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18477021

RESUMEN

INTRODUCTION: Acute malignant colorectal obstruction (CRO) can be satisfactorily dealt by the placement of a self-expanding metallic stent (SEMS). The aim of this prospective study was to evaluate the rate of elective (planned) colectomy (EPC) in patients with CRO after SEMS placement as a bridge to surgery on an intention-to-treat (ITT) basis. METHOD: From 2002 to 2007, 30 SEMS were placed as a bridge to surgery in 30 CRO patients (median age 73 +/- 12 years). The obstructing lesions were located in the right (n = 1), transverse (n = 1) or left colon (n = 24) or the upper third of the rectum (n = 4). RESULTS: The SEMS was placed successfully in 25 (83%) patients. Five patients underwent Hartmann's procedure (n = 2) or a diverting colostomy (n = 3). The SEMS was functionally operational in 23 (92%) of the 25 patients. A diverting colostomy was avoided in 23 (77%) of the 30 patients (placement failure n = 5, clinical failure n = 2). There were no complications in 17 (80%) patients. On an ITT basis, 70% of the patients (21 out of 30) underwent an EPC. CONCLUSION: On an ITT basis, SEMS placement in CRO patients enabled EPC in 70% of patients.


Asunto(s)
Colectomía/métodos , Neoplasias Colorrectales/cirugía , Procedimientos Quirúrgicos Electivos , Obstrucción Intestinal/cirugía , Stents , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/complicaciones , Constricción Patológica/cirugía , Femenino , Estudios de Seguimiento , Humanos , Obstrucción Intestinal/etiología , Masculino , Persona de Mediana Edad , Implantación de Prótesis/métodos
10.
Nutr Metab Cardiovasc Dis ; 19(1): 67-74, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19097768

RESUMEN

AIM: While empirical calculations are presently used, exact solutions to compute volume and solute changes of hyperosmolar coma (HC) can be obtained by subdividing the patients according to well defined clinical and laboratory conditions. These are represented by PNa(G), the plasma Na concentration that would be present if there were only glucose addition (GA), that discloses prevalent Na depletion when >PNa(1), prevalent water deficit when , = or

Asunto(s)
Hiperglucemia/complicaciones , Desequilibrio Hidroelectrolítico/diagnóstico , Desequilibrio Hidroelectrolítico/terapia , Glucemia/análisis , Coma/etiología , Simulación por Computador , Tratamiento de Urgencia , Fluidoterapia/métodos , Humanos , Coma Hiperglucémico Hiperosmolar no Cetósico/terapia , Hiponatremia/etiología , Hiponatremia/terapia , Hipovolemia/terapia , Insulina/administración & dosificación , Modelos Teóricos , Concentración Osmolar , Sensibilidad y Especificidad , Desequilibrio Hidroelectrolítico/etiología
11.
Exp Clin Endocrinol Diabetes ; 116(2): 86-93, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17972239

RESUMEN

INTRODUCTION: Obesity enhances insulin secretion and resistance. We investigated its importance in linking insulin metabolism to glucose intolerance. MATERIAL AND METHODS: We studied 700 subjects referred by general practitioners for possible metabolic abnormalities. Plasma glucose was measured before (FPG) and after (2h-PG) OGTT, together with insulin. Insulin resistance was estimated by HOMA-IR, insulin sensitivity using ISI(gly) and ISI(Stumvoll) indexes, insulin secretion by first (1stPH est) and second phase (2ndPH est) estimates. RESULTS: Sixty three subjects had impaired glucose tolerance (IGT), 132 impaired fasting glucose (IFG), 63 a mixed disorder (IFG/IGT). Insulin resistance was present only in IGT and IFG/IGT. IFG sub-jects had inappropriately low insulin secretionexclusively during fasting. In a stepwise logistic regression analysis BMI>or=27, female sex and hy-pertension were associated to an altered 2h-PG during OGTT, while hypertension and age were linked to alterations in FPG. While overweight prevalence (BMI>or=7) was higher in all glucose intolerance groups, obesity (BMI>or=30) was typical of IGT. Overweight and obesity were related to higher insulin concentration, secretion and resistance. Obese normal glucose tolerant subjects were more insulin resistant than lean IFG patients. DISCUSSION: OGTT is essential to correctly establish the metabolic derangement of glucose intolerance. Obesity is significantly connected with the impairment of insulin metabolism even in subjects with normal FPG. Considering that both obesity and insulin resistance are independently associated to an increased cardiovascular risk, all overweight subjects, even with normal FPG, should be referred for OGTT evaluation to define glucose tolerance status in order to enforce adequate preventive actions.


Asunto(s)
Intolerancia a la Glucosa/complicaciones , Intolerancia a la Glucosa/metabolismo , Obesidad/complicaciones , Obesidad/metabolismo , Adulto , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/etiología , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Hipertensión/complicaciones , Hipertensión/metabolismo , Insulina/metabolismo , Resistencia a la Insulina/fisiología , Masculino , Persona de Mediana Edad
12.
Hepatogastroenterology ; 55(85): 1327-31, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18795682

RESUMEN

BACKGROUND/AIMS: Endoscopic hemostasis and proton pump inhibitors (PPI) have decreased the incidence of rebleeding and reduced the need for surgery for bleeding duodenal ulcer (BDU). The gold standard surgical treatment of BDU remains vagotomy-antrectomy. Currently, no recommendation is made on the best procedure when emergency surgery is necessary. The aim of this study was to assess the results of a systematic conservative treatment (CT): under-running bleeding gastroduodenal artery (GDA) and ulcer suture through a duodenotomy with (CT+L group) or without (CT group) GDA double ligation along with continuous intravenous PPI. METHODOLOGY: From 1995 to 2006, 22 consecutive patients (11 per group) underwent emergency surgery for BDU. Mean age was 63 +/- 18 years, ASA score 2.64 +/- 0.7. Ten patients (45%) presented collapse. Mean transfusion number was 11 +/- 9, number of therapeutic endoscopies 1.7 +/- 1, and Rockall score 6 +/- 2. RESULTS: Overall, 2 patients (9%) had rebleeding and 5 patients (22%) died. No death was reported secondary to rebleeding. In the CT+L group, 9 patients (82%) had intravenous PPI, no patient had rebleeding and 2 patients died (22%). CONCLUSIONS: Surgical CT of BDU with continuous PPI is effective, with a low rate of rebleeding. The standard use of vagotomy-antrectomy is questionable.


Asunto(s)
Úlcera Duodenal/complicaciones , Hemostasis Quirúrgica/métodos , Úlcera Péptica Hemorrágica/tratamiento farmacológico , Úlcera Péptica Hemorrágica/cirugía , Inhibidores de la Bomba de Protones/uso terapéutico , Técnicas de Sutura , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Úlcera Duodenal/cirugía , Femenino , Humanos , Ligadura , Masculino , Persona de Mediana Edad , Úlcera Péptica Hemorrágica/etiología , Recurrencia , Retratamiento , Adulto Joven
13.
Eur J Intern Med ; 50: 3-5, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29395937

RESUMEN

BACKGROUND: The expansion of scientific publications makes more difficult the mining of relevant information necessary for a productive appraisal of authors' work, scientific interaction and exchange. Papers over-citation is unproductive, under-citation of innovative research generates delay and inefficiency. The extraction of information from the literature is mostly based on keywords (KWs). METHODS: I computed the chances of citation of one paper as 1/number of papers retrieved by the KWs published in that paper, and compared them with the chances obtained by selecting different KWs. RESULTS: Using generic KWs the chances are smaller, at times practically nil, as compared to those calculated with more specific KWs and their association. CONCLUSIONS: Selecting scientifically-analyzed KWs, specific for the message conveyed by a paper and computing beforehand the theoretical chances of citation, might increase the citations obtained, the retrieval of important scientific and innovative information, optimize scientific exchange and qualitative productivity. LEARNING POINTS.


Asunto(s)
Bibliometría , Almacenamiento y Recuperación de la Información , Publicaciones/normas , Humanos , Factor de Impacto de la Revista
14.
J Clin Invest ; 50(10): 2191-203, 1971 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-5116209

RESUMEN

The absolute rate of reabsorption by superficial rat proximal tubules was measured by the in situ microperfusion technique under conditions of hydropenia, infusion of saline, and infusion of saline plus aortic constriction sufficient to decrease whole kidney filtration rate below hydropenic levels. Fractional reabsorption was measured in adjacent filtering nephrons by collecting and recollecting tubular fluid from late proximal convolutions during each experimental condition. During hydropenia, the absolute rate of proximal tubular reabsorption averaged 3.56 +/-0.60 nl/min per mm and late proximal tubular fractional reabsorption averaged 0.56 +/-0.10. From these two measurements and measurements of tubule length to the site of micropuncture, a value for filtration rate was calculated for filtering nephrons. During hydropenia this value averaged 32.9 +/-7.1 nl/min. Saline infusion increased sodium excretion to 5.5% of the filtered load as the absolute rate of proximal tubular reabsorption decreased 38% and fractional reabsorption decreased 45%. Calculated superficial nephron filtration rate increased 21% which on the average was identical with the simultaneously measured increase in whole kidney filtration rate. Similar results were obtained in a separate group of animals by the technique of total collection of late proximal tubular fluid. Aortic constriction during saline infusion decreased whole kidney and calculated nephron filtration rate to the same degree and to values lower than those during hydropenia. Fractional reabsorption increased but not to hydropenic values. The persistent natriuresis during aortic constriction was associated with a continued depression of the absolute rate of proximal tubular reabsorption which was sufficient to maintain an increased delivery of filtrate out of the proximal tubule despite the fall in nephron filtration rate. These results indicate that depressed fractional reabsorption in the proximal tubule during acute saline infusion is due predominantly to a decrease in absolute reabsorptive rate and to a lesser extent to an increase in superficial nephron filtration rate which is proportional to the increase in whole kidney filtration. Continued natriuresis when filtration rate is decreased during saline infusion can be accounted for entirely by the persistent large reduction in the absolute rate of proximal tubular reabsorption.


Asunto(s)
Presión Sanguínea , Espacio Extracelular/fisiología , Glomérulos Renales/fisiología , Túbulos Renales/efectos de los fármacos , Natriuresis , Cloruro de Sodio/farmacología , Equilibrio Hidroelectrolítico , Ácidos Aminohipúricos , Animales , Coartación Aórtica/fisiopatología , Deshidratación/fisiopatología , Depresión Química , Tasa de Filtración Glomerular , Túbulos Renales/fisiología , Masculino , Perfusión , Punciones , Ratas
15.
J Clin Invest ; 52(4): 843-9, 1973 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-4693649

RESUMEN

Micropuncture techniques in the rat were used to reinvestigate the possibility that intraluminal flow rate per se may influence net volume reabsorption by the proximal tubule. An experimental design was devised which lowered intraluminal flow without affecting filtration rate of the nephron under study or without directly affecting other renal hemodynamics. In 11 rats flow of tubular fluid between early and late proximal tubular sites was reduced by partially collecting tubular fluid at the early puncture site. In 42 nephrons the rate of flow of tubular fluid was reduced an average of 45% without changing nephron filtration rate and there was an associated reduction in reabsorption between the two sites which averaged 29%. This indicated 63% balance between delivery of tubular fluid and the rate of reabsorption between two sites along proximal tubules. The results of these studies indicate that a reduction in delivery of normal filtrate along the proximal tubule is associated with a concordant reduction in the absolute rate of reabsorption. Since this relationship occurred in the absence of changes in renal hemodynamics or even a change in filtration rate of the nephron under study it is concluded that changes in intraluminal load per se play an important role in the phenomenon of glomerulotubular balance.


Asunto(s)
Túbulos Renales/fisiología , Absorción , Animales , Tasa de Filtración Glomerular , Inulina , Túbulos Renales Proximales/fisiología , Masculino , Ratas
16.
J Clin Invest ; 95(6): 2451-7, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7769090

RESUMEN

To determine whether decreased renal responsiveness to atrial natriuretic peptide (ANP) in diabetes is mediated by alterations in the renal ANP receptor, ANP receptor density and affinity were measured 17-20 d after streptozotocin injection and compared with values in vehicle-treated controls and streptozotocin-treated rats made euglycemic with insulin. Plasma ANP concentration was significantly greater in hyperglycemic diabetic rats than in control or euglycemic diabetic rats. Both in glomeruli and inner medulla, ANP receptor dissociation constant did not differ among the three study groups, whereas the maximum binding capacity was decreased significantly in hyperglycemic diabetics in comparison with controls and euglycemic diabetics. Glomerular clearance receptors were also decreased significantly in hyperglycemic diabetic rats in comparison with control and euglycemic diabetic rats. To determine whether the decreased number of renal ANP receptors in diabetic rats was associated with a decreased biological response, we measured ANP-dependent cyclic GMP (cGMP) accumulation by isolated glomeruli and inner medullary collecting duct cells in vitro. cGMP accumulation was significantly less in hyperglycemic diabetic rats than in controls or euglycemic diabetic rats both in the presence or absence of the phosphodiesterase inhibitor zaprinast. cGMP phosphodiesterase activity in inner medullary collecting duct cells obtained from control and hyperglycemic diabetic rats did not differ. Thus, the decreased number of biologically active ANP receptors in the kidneys of diabetic rats is accompanied by decreased biological responsiveness in vitro and provides a potential explanation for the reduction in renal sensitivity to ANP in this condition.


Asunto(s)
Factor Natriurético Atrial/metabolismo , Diabetes Mellitus Experimental/metabolismo , Riñón/metabolismo , Receptores del Factor Natriurético Atrial/metabolismo , Animales , Autorradiografía , Peso Corporal , Membrana Celular/metabolismo , GMP Cíclico/metabolismo , Citosol/metabolismo , Guanilato Ciclasa/metabolismo , Glomérulos Renales/metabolismo , Masculino , Hidrolasas Diéster Fosfóricas/metabolismo , Ensayo de Unión Radioligante , Ratas , Ratas Sprague-Dawley , Transducción de Señal
18.
Exp Clin Endocrinol Diabetes ; 115(2): 112-7, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17318771

RESUMEN

INTRODUCTION: With the objective to assess the diagnostic power of the ADA criteria in detecting glucose intolerance, we studied 654 patients by performing an oral glucose tolerance test (OGTT). MATERIAL AND METHODS: The design required computing sensitivity, specificity and predictive values for different cut-off levels of fasting plasma glucose (FPG). The patients were recruited in an outpatient facility of a General Internal Medicine department affiliated to a Medical School. RESULTS: Lowering the threshold from 7.0 to 6.1, 5.6, 5.0 and 4.4 mmol/l (126 to 110, 100, 90 and 80 mg/dl) respectively, resulted in a progressive fall in specificity (99.6, 91.6, 76.0, 45.3 and 15.8%) combined to a rise in sensitivity (8.6, 30.7, 56.4, 76.4 and 92.9%). Two subjects with FPG <5.0 mmol/l were diabetic. At the lowest FPG of 4.4 mmol/l the percentage of glucose intolerant patients by OGTT was still 11% while at 6.1 mmol/l the false positive rate was 50%. DISCUSSION: The simple screening based on FPG alone, as suggested by ADA, is ineffective, not detecting an unacceptable number of subjects with glucose intolerance, and conveys the high cost of working up an excessively large number of false positives. Only the OGTT represents the effective screening procedure.


Asunto(s)
Glucemia/análisis , Ayuno/sangre , Intolerancia a la Glucosa/diagnóstico , Prueba de Tolerancia a la Glucosa/métodos , Adulto , Femenino , Intolerancia a la Glucosa/sangre , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Estudios Retrospectivos , Sensibilidad y Especificidad
19.
J Chir (Paris) ; 144(1): 35-8, 2007.
Artículo en Francés | MEDLINE | ID: mdl-17369760

RESUMEN

BACKGROUND: Cutaneous fistulas from the rectal stump after Hartmann procedure are not rare. Rarely do they require operative intervention, but they may result in prolonged skin care during hospitalization. PURPOSE: of study: To describe the use of fibrin glue in the treatment of rectocutaneous fistulas occurring after Hartmann procedure. STUDY DESIGN: Ten patients underwent irrigation of the fistulous tract followed by fibrin glue injection. The glue was reconstituted using the usual two syringe admixture technique; the tract was catheterized as far as the rectal stump, and the glue was injected as the catheter was withdrawn to skin level. RESULTS: No complications were noted and the discharge from seven out of ten fistulas dried up completely. CONCLUSION: Biologic glue occlusion of rectocutaneous fistulas simplified local care and decreased hospital stay.


Asunto(s)
Colostomía/efectos adversos , Fístula Cutánea/terapia , Adhesivo de Tejido de Fibrina/uso terapéutico , Fístula Rectal/terapia , Adhesivos Tisulares/uso terapéutico , Adenocarcinoma/cirugía , Anciano , Anciano de 80 o más Años , Cateterismo/instrumentación , Diverticulitis del Colon/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Proctoscopía , Enfermedades del Sigmoide/cirugía , Neoplasias del Colon Sigmoide/cirugía , Irrigación Terapéutica , Resultado del Tratamiento
20.
Clin Microbiol Infect ; 12(8): 787-92, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16842575

RESUMEN

The prevalence and associated factors of chronic uncomplicated strongyloidiasis were estimated among 200 consecutive elderly patients (aged >or= 60 years) admitted to a general hospital in northern Italy. One-hundred patients had a peripheral eosinophil concentration >or= 500 cells/microL (group A), and 100 were age- and gender-matched controls (group B). Measurements included serum IgG anti-Strongyloides antibody titre by an indirect immunofluorescence assay, combined with faecal culture for Strongyloides stercoralis. Anti-Strongyloides antibodies were detected in 28 patients (at high titre in 11 patients). Seropositivity was significantly more common among group A than among group B patients (OR 4.85). Strong seropositivity for anti-Strongyloides antibodies was associated with farm work (p < 0.001), but not with other patient characteristics or with signs and symptoms of strongyloidiasis. In conclusion, strongyloidiasis was relatively common among elderly in-patients; eosinophilia and a history of farm work were the most useful indications for this diagnosis.


Asunto(s)
Eosinofilia/parasitología , Estrongiloidiasis/epidemiología , Anciano , Anciano de 80 o más Años , Anticuerpos Antihelmínticos/sangre , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Hospitalización , Humanos , Masculino , Estudios Prospectivos , Estudios Seroepidemiológicos , Estrongiloidiasis/diagnóstico
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