Search PubMed⌕ Search

Biomedical subjects

M Casado

Publications and source records attributed to M Casado.

At least 19 recordsLinked to original sources
PubMed2002

[Amoxicillin-clavulanic acid induced hepatotoxicity with progression to cirrhosis].

Amoxicillin-clavulanic acid is a commonly used antibiotic in clinical practice. It is usually prescribed on an empirical basis and several cases of hepatotoxicity with cholestasis have been described. We report the case of a 42-year-old man who developed an acute hepatocellular lesion with progression to cirrhosis. The patient received amoxicillin-clavulanic acid twice with an interval of four months. Other causes of hepatic failure were excluded. Although amoxicillin-clavulanic acid-induced hepatotoxicity has been widely documented, there are no other reports describing its progression to cirrhosis in an adult.

Adult↗
PubMed2001

Contribution of cyclooxygenase 2 to liver regeneration after partial hepatectomy.

Partial hepatectomy (PH) triggers a rapid regenerative response in the remaining tissue to reinstate the organ function and the cell numbers. Among the molecules that change in the course of regeneration is an accumulation of prostaglandin E2 in the sera of rats with PH. Analysis of the cyclooxygenase (COX) isoenzymes in the remnant liver showed the preferential expression of COX-2 in hepatocytes. Cultured regenerating hepatocytes expressed significant levels of COX-2, a process that was not observed in the sham counterparts. Maximal expression of COX-2 was detected 16 h after PH with increased levels present even at 96 h. Pharmacological inhibition of COX-2 activity with NS398 shunted the up-regulation of cell proliferation after PH, which suggests a positive interaction of prostaglandins with the progression of the cell cycle. Similar results were obtained after PH of mice lacking the COX-2 gene. The expression of COX-2 in regenerating liver was concomitant with a decrease in CCAAT-enhancer binding protein (C/EBP-a) level and an increase in the expression of C/EBP-b and C/EBP-d. These results suggest a contribution of the enhanced synthesis of prostaglandins to liver regeneration observed after PH.

Animals↗
PubMed2001

[Predictive factors of the mortality of digestive hemorrhage caused by esophageal varices in elderly patients].

Complications of liver cirrhosis are increasingly frequent in elderly patients due to increased life expectancy and better management of cirrhotic patients. However, the influence of this condition on the evolution of variceal bleeding has not been well established. The aim of the present study was to determine the characteristics of esophagogastric variceal bleeding in elderly patients and the possible influence of advanced age on hemorrhage-related mortality. We analyzed 321 episodes of variceal bleeding in 227 cirrhotic patients. One hundred and thirteen (35.2%) episodes occurred in patients older than 65 years. No differences were found among patients older or younger than this age in terms of bleeding characteristics or Child-Pugh score. Patients older than 65 years more frequently presented serious associated diseases, hepatocellular carcinoma and hepatic encephalopathy during the episode (52.7% vs. 14%, p < 0.001; 19.7% vs. 8.7%, p = 0.01 and 17.4% vs. 10%, p = 0.09 respectively). Although hemorrhage-related mortality was higher in elderly patients (23.2% vs. 13.5%, p = 0.04), only the Child-Pugh score, definitive hemostasis, hepatocellular carcinoma and the development of encephalopathy or bacterial infection were independent predictive factors of mortality. A considerable proportion of the patients with esophagogastric variceal bleeding were older than 65 years. Advanced age does not independently influence mortality due to variceal bleeding.

Aged↗
PubMed2001

Randomized controlled trial of aspiration needle versus automated biopsy device for transjugular liver biopsy.

PURPOSE: The efficacy and safety of transjugular liver biopsy used to obtain liver specimens in patients with coagulation disorders have been widely proven. However, histopathologic examination is not always possible because of fragmented samples provided by the aspiration technique. Recently, an automated device with a Tru-Cut-type needle was designed. In this randomized controlled trial, the use of this new device is compared with the traditional method in terms of efficacy and safety. METHOD: Fifty-six patients were included in the study; 28 were randomized to undergo the aspiration technique and 28 were randomized to undergo the automated biopsy technique. RESULTS: Correct positioning of the device was achieved in 93% of patients undergoing the aspiration technique and 96% of patients undergoing the automated biopsy technique (P = NS). Mean duration of the procedure and total number of passes were significantly higher in the aspiration needle group than in the automated device group (22.6 min +/- 12.6 vs 15.5 min +/- 9.4; P = .03, and 3.3 min +/- 1.9 vs 1.5 min +/- 0.63; P < .001, respectively). The number of portal tracts was significantly higher in the automated device group (4.7 +/- 2.5 vs. 2.7 +/- 3.4; P < .05). Adequate specimens for histopathologic evaluation were obtained in 26 patients in the automated device group and 24 patients in the aspiration needle group (92.8% vs 85.7%; P = NS), but a definite histopathologic diagnosis was more frequently obtained with the automated biopsy device (68% vs 43%; P = .05). No significant differences were observed in complication rates (7.14% vs. 10.7%; P = NS). CONCLUSION: The automated biopsy device for transjugular liver biopsy is more effective than an aspiration needle in obtaining good samples for a definite histologic diagnosis.

Adult↗
PubMed2001

Expression of cyclooxygenase-2 promotes the release of matrix metalloproteinase-2 and -9 in fetal rat hepatocytes.

Treatment of primary cultures of fetal hepatocytes with proinflammatory cytokines, lipopolysaccharide (LPS), and hepatocyte growth factor promoted the expression of cyclooxygenase-2 (COX-2) and the synthesis of high amounts of prostaglandins (PGs). Under these conditions, the active forms of the matrix metalloproteinases-2 and -9 (MMPs) were released to the extracellular medium. This process was inhibited when the synthesis of PGs was suppressed pharmacologically with COX-2 inhibitors. Addition to the cell cultures of PGE(2) promoted the release of MMPs through a mechanism that involved the expression of COX-2 and the synthesis of additional PGs. Kinetic analysis of the secretion of MMPs in response to LPS and PGE(2) showed a similar time course, with a lag period of 6 hours, which suggests that PGE(2) does not act directly on the mechanism of MMP processing and release. Inhibitors of protein kinase A, p38 MAP kinase, phosphatidylinositol-3-kinase, and nuclear factor kappaB (NF-kappaB) activation impaired the release of MMPs in response to PGE(2) challenge, indicating the involvement of multiple steps in the process. The ability of fetal hepatocytes to release MMPs in response to growth factors and inflammatory stimuli constitutes a model for the study of the extracellular matrix remodeling that accompanies most liver diseases.

Animals↗
PubMed2000

Presynaptic N-methyl-D-aspartate receptors at the parallel fiber-Purkinje cell synapse.

At the cerebellar synapse between the parallel fibers (PFs) and the Purkinje cells in the cerebellum, we have found that application of N-methyl-d-aspartate (NMDA) reversibly depresses the postsynaptic current. We present evidence that this depression involves NMDA receptors located on the presynaptic axons and requires that the NMDA application be combined with action potentials in the PFs. Unexpectedly, unlike other modulations mediated by presynaptic receptors, the NMDA-induced inhibition does not involve a depression of transmitter release. Because it is blocked by both nitric oxide synthase and soluble guanylate cyclase inhibitors, we propose that it involves a trans-synaptic mechanism in which NO released by the PFs decreases the glutamate sensitivity of the Purkinje cell.

Animals↗
PubMed2000

Successful treatment of aphthous ulcerations in AIDS patients using topical granulocyte-macrophage colony-stimulating factor.

Oral recurrent aphthous ulceration (RAU) is a well-recognized complication in patients infected with human immunodeficiency virus. RAU can be progressive and destructive, causing dysphagia and secondary malnutrition. The aetiology of RAU remains unknown, and its response to available treatments is often unsatisfactory. We describe three patients with advanced AIDS who suffered from extensive RAU which failed to respond to several treatments, including topical viscous lidocaine and topical and systemic glucocorticoids. Owing to difficulties in using thalidomide (two patients had neurological conditions which precluded thalidomide use), all three patients were treated with an oral solution containing recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF, 400 microg in 5% glucose 200 mL). From the first application, all three patients showed significant improvement of their lesions and amelioration of pain, and they were completely cured in a few days. No adverse effects were recorded. The patients did not show relapses of RAU over a prolonged follow-up. Controlled trials are warranted in order to establish the role of GM-CSF as a valid, alternative option for aphthous ulcerations of the mouth in AIDS patients in whom corticosteroids or thalidomide are not suitable.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Mondor's disease.

BACKGROUND: Mondor's disease is a rare entity characterized by thrombophlebitis of the subcutaneous veins of the anterolateral thoraco-abdominal wall. The most common clinical manifestations are a painful subcutaneous cord, sensation of tension, and skin retraction. This condition is usually a benign and self-limited process, although it has been associated with breast cancer. METHODS: We describe four new cases, two men and two women, and comment on the clinical signs and possible etiopathogenic features. General physical examination, radiologic and ecographic studies, laboratory analysis including tumor markers, and exhaustive coagulation study were carried out on all patients. RESULTS: No cases were associated with malignant disease and/or hypercoagulability stage. With conservative treatment, the evolution proved favorable in all patients. CONCLUSIONS: Mondor's disease is usually a benign and self-limited process, but we recommend laboratory studies and physical examination, including mammography in women, in order to rule out the presence of systemic disorders, especially breast cancer.

Abdominal Muscles↗
PubMed1999

Essential role in vivo of upstream stimulatory factors for a normal dietary response of the fatty acid synthase gene in the liver.

In the liver, transcription of several genes encoding lipogenic and glycolytic enzymes, in particular the gene for fatty acid synthase (FAS), is known to be stimulated by dietary carbohydrates. The molecular dissection of the FAS promoter pointed out the critical role of an E box motif, located at position -65 with respect to the start site of transcription, in mediating the glucose- and insulin-dependent regulation of the gene. Upstream stimulatory factors (USF1 and USF2) and sterol response element binding protein 1 (SREBP1) were shown to be able to interact in vitro with this E box. However, to date, the relative contributions of USFs and SREBP1 ex vivo remain controversial. To gain insight into the specific roles of these factors in vivo, we have analyzed the glucose responsiveness of hepatic FAS gene expression in USF1 and USF2 knock-out mice. In both types of mouse lines, defective in either USF1 or USF2, induction of the FAS gene by refeeding a carbohydrate-rich diet was severely delayed, whereas expression of SREBP1 was almost normal and insulin response unchanged. Therefore, USF transactivators, and especially USF1/USF2 heterodimers, seem to be essential to sustain the dietary induction of the FAS gene in the liver.

Animals↗
PubMed1999

Carvedilol, a new nonselective beta-blocker with intrinsic anti- Alpha1-adrenergic activity, has a greater portal hypotensive effect than propranolol in patients with cirrhosis.

Only some patients show a substantial hepatic venous pressure gradient (HVPG) reduction after propranolol, which makes it desirable to investigate drugs with greater portal hypotensive effect. The aim of this study was to investigate whether carvedilol, a nonselective beta-blocker with anti-alpha1-adrenergic activity, may cause a greater HVPG reduction than propranolol. Thirty-five cirrhotic patients had hemodynamic measurements before and after the random administration of carvedilol (n = 14), propranolol (n = 14), or placebo (n = 7). Carvedilol markedly reduced HVPG, from 19.5 +/- 1.3 to 15.4 +/- 1 mm Hg (P <.0001). This HVPG reduction was greater than after propranolol (-20.4 +/- 2 vs. -12.7 +/- 2%, P <.05). Moreover, carvedilol decreased HVPG greater than 20% of baseline values or to </=12 mm Hg in a greater proportion of patients (64% vs. 14%, P <.05). Both drugs caused similar reductions in hepatic and azygos blood flows, suggesting that the greater HVPG decrease by carvedilol was because of reduced hepatic and portocollateral resistance. Propranolol caused greater reductions in heart rate and cardiac output than carvedilol, whereas carvedilol caused a greater decrease in mean arterial pressure (-23.1 vs. -11%, P <.05). Thus, carvedilol has a greater portal hypotensive effect than propranolol in patients with cirrhosis, suggesting a greater therapeutic potential. However, it causes arterial hypotension, which calls for careful evaluation before its long-term use.

Adrenergic alpha-Antagonists↗
PubMed1999

Requirement of nuclear factor kappaB for the constitutive expression of nitric oxide synthase-2 and cyclooxygenase-2 in rat trophoblasts.

Recently isolated trophoblasts express nitric oxide synthase 2 (NOS-2) and cyclooxygenase 2 (COX-2), decreasing the levels of the corresponding mRNAs when the cells were maintained in culture. The sustained expression of COX-2 and NOS-2 in trophoblasts was dependent on the activation of nuclear factor kappaB (NF-kappaB) since proteasome inhibitors and antioxidants that abrogated NF-kappaB activity suppressed the induction of both genes. The time-dependent fall of the mRNA levels of NOS-2 and COX-2 paralleled the inhibition of NF-kappaB, determined by electrophoretic mobility shift assays, and the increase of the IkappaBalpha and IkappaBbeta inhibitory proteins. Isolated trophoblasts synthesized reactive oxygen intermediates (ROI), a process impaired after culturing the cells, and that might be involved in the NF-kappaB activation process. Moreover, treatment of recently isolated cells with ROI scavengers suppressed the expression of COX-2 and NOS-2. Challenge of trophoblasts with interleukin-1beta up-regulated the expression of both proteins, an effect that was potentiated by lipopolysaccharide. These results indicate that the physiological expression of NOS-2 and COX-2 in trophoblasts involves a sustained activation of NF-kappaB which inhibition abrogates the inducibility of both genes.

Animals↗
PubMed1999

Epithelial sodium channel in human epidermal keratinocytes: expression of its subunits and relation to sodium transport and differentiation.

The amiloride-sensitive epithelial sodium channel (ENaC) is a main determinant of sodium absorption in renal and colonic epithelial cells. Surprisingly, it is also expressed in non-transporting epithelia such as the epidermis. To gain insight into the putative role of ENaC in keratinocytes, we have evaluated its expression in human skin and in cultured human keratinocytes. Our results indicate that (1) ENaC is expressed in the epidermis and in cultured keratinocytes, at the mRNA and at the protein levels, (2) the ratio of expression of the different ENaC subunits is drastically modified at the protein level during cell growth and differentiation, with a selective upregulation of the &bgr; subunit, (3) no transepithelial sodium transport function is apparent in cultured keratinocytes, but patch-clamp recordings indicate the existence of functional sodium channels with properties similar to those of the cloned ENaC and (4) ENaC inhibition does not alter keratinocyte proliferation, but it significantly decreases the frequency of dome formation in confluent keratinocyte cultures. These results document for the first time the characteristics of ENaC subunit expression in human keratinocytes, and suggest that ENaC may be important during differentiation.

Amiloride↗