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J Dominguez

Publications and source records attributed to J Dominguez.

At least 37 records · Page 2Linked to original sources

A prognostic index of the survival of patients with unresectable hepatocellular carcinoma after transcatheter arterial chemoembolization.

BACKGROUND: Transcatheter arterial chemoembolization (TACE) has been used as a palliative treatment for patients with unresectable hepatocellular carcinoma (HCC), but its prognostic usefulness has not previously been clarified. METHODS: The authors reviewed all patients treated at their institution with TACE for unresectable HCC in order to analyze prognostic factors and to determine which patients might benefit from this treatment. One hundred forty-three patients were retrospectively studied. Pretreatment, treatment, and follow-up variables with possible prognostic significance were analyzed. A stepwise multivariate analysis was performed using the Cox regression model, and a prognostic index was obtained. RESULTS: According to univariate analysis, variables significantly associated with survival were alpha-fetoprotein (>400 U/L), tumor size (>50%), ascites, albumin (<30 g/L), Child-Pugh grade (Child C), Okuda stage (Okuda III), portal vein thrombosis, tumor greatest dimension larger than 5 cm, more than 3 nodules, bilobular involvement, and pattern of iodized oil uptake, tumor size reduction, and radiologic T classification on computed tomography scan performed 7 and 30 days after TACE. However, only ascites, alpha-fetoprotein (>400 U/L), tumor size (>50%), Child-Pugh grade (Child C), pattern of iodized oil uptake, and portal vein thrombosis were independent factors in multivariate analysis. Using the beta-coefficients of alpha-fetoprotein (>400 U/L), tumor size (>50%) and Child-Pugh score, a prognostic index was calculated, and according to this index patients were classified into 3 categories with different prognoses. Ascites was excluded from the analysis because it is included in Child-Pugh grade, and iodized oil uptake was excluded because it cannot be evaluated before treatment. CONCLUSIONS: This simple prognostic index can predict the survival of patients treated with TACE and can therefore be used to decide which patients with unresectable HCC should receive this therapy. TACE should not be administered to patients with one or more positive prognostic factors.

Actuarial Analysis↗

Percutaneous embolization of the failed renal allograft in patients with graft intolerance syndrome.

OBJECTIVE: To analyse the circumstances, results and complications of percutaneous embolization in failed renal grafts that are not tolerated, to avoid surgical graft removal in selected patients. PATIENTS AND METHODS: The study included 33 patients (mean age 42 years, SD 13.9) whose renal grafts failed between 1990 and 1999. The patients underwent percutaneous embolization of their renal transplant for graft intolerance syndrome. The allograft was left in situ after failure for a mean (SD) of 9.9 (6.5) months. The subsequent hospital stay, the appearance of complications and the final results were assessed. RESULTS: Post-embolization syndrome (fever for 2-5 days) appeared in 20 (61%) of the patients; the clinical intolerance resolved in 28 (85%). The embolization was unsuccessful in five of the 33 patients (15%) and they required graft removal. The mean (SD) hospital stay was 5 (2) days; there were no major complications from graft embolization. CONCLUSIONS: Graft embolization avoids kidney removal in many patients with failed and rejected transplants, with low rates of morbidity. Surgical graft nephrectomy was useful when graft intolerance syndrome persisted after embolization.

Adult↗

Human Cdc25 A inactivation in response to S phase inhibition and its role in preventing premature mitosis.

The Cdc25 A phosphatase is required for the G1-S transition of the cell cycle and is overexpressed in human cancers. We found that it is ubiquitylated and rapidly degraded by the proteasome and that its levels increase from G1 until mitosis. By treating cells with the DNA synthesis inhibitor hydroxyurea, Cdc25 A rapidly decreased in abundance, and this was accompanied by an increase in Cdk2 phosphotyrosine content and a decrease in Cdk2 kinase activity. Cdc25 A overexpression altered the ability of cells to arrest in the presence of hydroxyurea, and caused them to undergo premature chromosome condensation. Cdc25 A overexpression could render tumor cells less sensitive to DNA replication checkpoints, thereby contributing to their genomic instability.

Bromodeoxyuridine↗

Partial antagonism of 8-OH-DPAT'S effects on male rat sexual behavior with a D2, but not a 5-HT1A, antagonist.

The serotonin agonist 8-hydroxy-di-propylaminotetralin (8-OH-DPAT), injected systemically or directly into the medial preoptic area (MPOA), reduces the ejaculatory threshold in male rats. While 8-OH-DPAT has been characterized as an agonist at the 5-HT1A receptor, it also acts at other receptor sites including the dopamine D2 receptor. The current experiments investigated whether 8-OH-DPAT injected into the MPOA facilitates male sexual behavior through stimulation of the 5-HT1A receptor or the dopamine D2 receptor. Experiment 1 co-administered 8-OH-DPAT (6 microgram) with either the 5-HT1A antagonist 4-iodo-N-[2-[4-(methoxyphenyl)-1-piperazinyl]ethyl]-N-2-pyridinyl-ben zamide hydrochloride (MPPI) (10 microgram) or the D2 antagonist raclopride (10 microgram). Raclopride blocked 8-OH-DPAT's facilitative effects on ejaculation frequency and latency, while the 5-HT1A antagonist was ineffective. In Experiment 2, 8-OH-DPAT (500 microM), retrodialyzed into the MPOA through a microdialysis probe, enhanced male copulatory behavior similarly to the microinjection, increasing ejaculation frequency and decreasing ejaculation latency, postejaculatory interval and mount frequency. Retrodialyzing 8-OH-DPAT through a microdialysis probe in the MPOA had been previously shown to increase extracellular levels of dopamine and serotonin. The data from the present studies suggest that the effects of 8-OH-DPAT in the MPOA on male rat copulatory behavior may be mediated, at least in part, either directly through 8-OH-DPAT's activity at D2 receptors or indirectly through 8-OH-DPAT's ability to increase extracellular dopamine.

8-Hydroxy-2-(di-n-propylamino)tetralin↗

Complete resolution of post-traumatic high-flow priapism with conservative treatment.

The most frequent cause of high-flow priapism is penile or perineal closed trauma with laceration of the cavernous artery and the formation of an arterial-lacunar fistula. We present the case of a high-flow priapism due to closed perineal trauma and damage to the left cavernous artery which completely resolved following conservative treatment. The case was documented by duplex Doppler ultrasound and selective pudendal arteriogram before and after resolution.

Adult↗

Effect of recombinant human erythropoietin on endothelial cell apoptosis.

BACKGROUND: Recombinant human erythropoietin (rHuEPO) induces endothelial cell growth and angiogenesis in vitro. The mechanisms are unknown. Because an increase in endothelial cell survival could play a role in this process, we examined the effect of rHuEPO on lipopolysaccharide (LPS)-induced apoptosis in bovine pulmonary artery endothelial cells (BPAECs). METHODS: Four groups of cells were studied. The first group was preincubated in serum-free medium followed by treatment with LPS. The second group was preincubated with rHuEPO followed by LPS. The third group was treated with only rHuEPO. Control cells were cultured in the absence of rHuEPO and LPS. Apoptosis was determined by flow cytometric DNA analysis, propidium iodide staining, cellular DNA fragmentation by ELISA, and gel electrophoresis. RESULTS: LPS-treated cells showed an increase in hypodiploid DNA (36.4 +/- 6.1%) compared with controls (9.8 +/- 3.3%, P < 0.001). Preincubation with rHuEPO decreased this effect to 14.7 +/- 5.1% (P < 0.001). Apoptosis determined by propidium iodide was observed in 33 +/- 8% of LPS-treated cells, but in only 9 +/- 3% of cells preincubated with rHuEPO cells (P < 0.001). Similarly, DNA fragmentation was decreased in rHuEPO pretreated cells compared with LPS alone (0.155 OD +/- 0.02 vs. 0.538 +/- 0.09 OD, P < 0.001). DNA breakdown was observed in only LPS-treated cells. CONCLUSIONS: These results suggest that rHuEPO prevents LPS-induced apoptosis in endothelial cells. This protective effect could be an important factor in the action of rHuEPO on vascular endothelium.

Animals↗

Accuracy of polyp detection by gastroenterologists and nurse endoscopists during flexible sigmoidoscopy: a randomized trial.

BACKGROUND & AIMS: The use of nurse endoscopists to perform flexible sigmoidoscopy is expanding, increasing the availability of colorectal cancer screening. However, the effectiveness of this practice has not been studied in randomized trials. The aim of this trial was to examine the miss rate of polyps, the depth of sigmoidoscope insertion, and the incidence of complications during flexible sigmoidoscopy performed by nurse endoscopists and by gastroenterologists. METHODS: Three hundred twenty-eight patients were randomized to undergo screening flexible sigmoidoscopy performed by a nurse endoscopist or by a gastroenterologist. Frequency of missed polyps was determined by repeat sigmoidoscopy, performed by a gastroenterologist blinded to the identity of the first endoscopist. Multiple logistic regression analysis identified characteristics associated with missed polyps. RESULTS: Gastroenterologists and nurse endoscopists had equivalent miss rates for adenomatous polyps (20% vs. 21%, respectively; P = 0.91). No complications occurred in any patient. Gastroenterologists inserted the sigmoidoscope further than nurse endoscopists (61 vs. 55 cm, respectively; P < 0.00001). Polyp location in the descending colon (odds ratio, 4.1; 95% confidence interval, 1.7-10.3) was highly associated with missed polyps. CONCLUSIONS: No differences in detection of adenomatous polyps or frequency of complications were found. These data suggest that experienced nurse endoscopists may perform screening flexible sigmoidoscopy as safely and as effectively as gastroenterologists.

Adult↗

Proteasome-dependent degradation of p27/kip1 in gliomas.

p27/kip1 regulates the G1-S transition of the cell cycle by inhibiting cyclin D-CDK4, cyclin E-CDK2, and cyclin A-CDK2. Modulation of p27 cellular abundance occurs mainly at post-translational level by the ubiquitin-proteasome proteolysis. Although rearrangements and mutations of p27/kip1 are extremely rare events, p27 levels are reduced and associated with a poor prognosis in many human carcinomas. In astrocytic tumors, p27 decreases with advancing anaplasia and is almost absent in glioblastomas. To verify whether the degradation of p27 protein was responsible for its reduced levels in malignant gliomas, p27 degradation activity was tested in 22 tissue extracts that represented high, low, and absent p27 protein levels. p27 protein expression was detected by immunohistochemistry and immunoblot analysis and comparable results between the 2 methods were obtained. Low or undetectable p27 degradation activity was found in samples that displayed high levels of p27, i.e. all 4 normal brain biopsies, and 4 out of 6 grade II astrocytomas. Enhanced degradation activity resulted in malignant gliomas with low or absent p27 protein levels. The proteasome inhibitor LLnL abolished p27 degradation, demonstrating that it occurs in a proteasome-dependent manner. These data suggest that proteasome degradation of p27 may be instrumental in the deregulation of the cell cycle and to the malignant transformation of gliomas.

Astrocytoma↗

Analysis of the immunological cross reactivities of 213 well characterized monoclonal antibodies with specificities against various leucocyte surface antigens of human and 11 animal species.

213 Monoclonal antibodies (mAbs) raised against leucocyte surface antigens from human and 11 animal species were analyzed for reactivities against leucocytes from human and 15 different animal species. We found 77 mAbs (36%) to cross-react. Altogether, 217 cross reactions were registered out of 3195 possible combinations (7%). Most of the cross reacting mAbs had integrin or MHC class II specificities. This study defined cross reactions on the following markers: CD1a, 1c, 2, 4, 5, 8, 9, 11a, 11b, 14, 18, 20, 21, 23, 29, 31, 41, 43, 44, 45, 45R, 46, 49, 61, 62L, TCR gamma/delta, BCR, Thy-1, MHC class I and MHC class II, Swine-WC7 and Cattle-WC1. In order to characterize the molecular weight (MW) of the corresponding cross reacting antigens, selected mAbs were used to immunoprecipitate the antigens. The MW's of the analyzed precipitated antigens were in good agreement with the MWs of the homologous antigens. The followed strategy was found to be efficient and economical in defining new leucocyte antigen reactive mAbs.

Animals↗

Overview of the Second International Workshop to define swine cluster of differentiation (CD) antigens.

The aim of the Second International Swine Cluster of Differentiation (CD) Workshop, supported by the Veterinary Immunology Committee (VIC) of the International Union of Immunological Societies (IUIS), was to standardize the assignment of monoclonal antibodies (mAb) reactive with porcine leukocyte differentiation antigens and to define new antibody clusters. At the summary meeting of the workshop in July, 1995, revisions in the existing nomenclature for Swine CD were approved, so that the rules are now in accord with those for human and ruminant CD. Swine CD numbers will now be given to clusters of mAb to swine orthologues of human CD molecules when homology is proven by (1) suitable tissue distribution and lymphoid cell subset expression, (2) appropriate molecular mass of the antigen recognized by the mAbs, and (3) reactivity of mAbs with the cloned swine gene products, or cross-reactivity of the mAb on the human gene products. In some cases, this reactivity would not be fully proven, mainly due to the lack of cloned gene products; for these CD antigens, the respective clusters will be assigned by the prefix 'w' which will lead to 'wCD' antigens. As a result of the Second International Swine CD Workshop the assignment of 16 mAb to existing CD groups (CD2a, CD4a, CD5a, wCD6, wCD8, CD14, CD18a, wCD21, wCD25) was confirmed, and 2 mAb to existing swine workshop clusters (SWC). More importantly, for the work on the porcine immune system, was the definition of 5 new swine CD antigens, namely CD3 (recognized by 6 new mAb and 3 epitopes), CD16 (1 new mAb), wCD29 (2 mAb), CD45RA (3 mAb) and CD45RC (1 new mAb). Finally, the demarcation of two new SWC molecules in swine, SWC8 (2 mAb) and SWC9 (2 mAb) was confirmed.

Animals↗

Summary of workshop findings for antibodies reacting with porcine T-cells and activation antigens: results from the Second International Swine CD Workshop.

After initial evaluation of the 176 new and 19 control monoclonal antibodies (mAb) submitted to the Second International Swine CD Workshop, 57 were assigned to the T-cell/activation marker subgroup. These 57 mAb were further analyzed using flow cytometry on whole blood lymphocytes, splenocytes, Peyer's patch lymphocytes, in vitro cell lines, broncho-alveolar lavage cells, Con A and PHA blasts, fetal cell populations, and by 2-color flow cytometry against mAb to porcine CD2, CD4, and CD8. Finally, the molecular weights of the target antigens were characterized when possible. As a result of these analyses, 23 mAb were distributed into 7 CD clusters. Newly confirmed mAb assignments included: two CD2; one CD4; two CD5; one wCD6; and one wCD25. Three new mAb were found that reacted with wCD8, one of which defined a new epitope, wCD8c. For the first time, mAb against porcine CD3 were identified, including 6 mAb that reacted with three different epitopes. Several new mAb reacted with antigens whose expression varied depending on the activation state of the test cell. These will require further characterization in order to assign a CD number.

Animals↗

Analyses of monoclonal antibodies reacting with porcine CD3: results from the Second International Swine CD Workshop.

Among the 57 monoclonal antibodies (mAb) analyzed within the T-cell group from the Second Swine CD Workshop, six mAb fell within clusters T10 and T11 (No. 088, STH164; No. 148, FY1A3; No. 149, FY2C1; No. 150, FY1H2; No. 151, FY2A11; No. 169, BB23-8E6). The mAb within these two groups gave a similar appearance on flow cytometry and stained all peripheral blood T-cells as defined by CD4 and wCD8 staining. All six mAb precipitated a 24 kDa protein. On the basis of inhibition analyses performed as part of the workshop and from published data, the mAb define at least three epitopes. There is only minimal stimulation of resting peripheral lymphocytes, but four of the mAb produce strong stimulation in the presence of PMA. With the exception of STH164, all have been shown to react with CD3 epsilon-transfected COS cells. The new mAb, therefore, react with three epitopes on porcine CD3 epsilon designated CD3a (BB23-8E6, FY2A11), CD3b (FY1A3, FY2C1), and CD3c (FY1H2). mAb STH164 appears to be reactive with another epitope, however, since its reactivity with CD3 has not been confirmed it is designated as wCD3.

Animals↗

Analyses of monoclonal antibodies reacting with porcine CD5: results from the Second International Swine CD Workshop.

Among the 57 monoclonal antibodies analyzed within the T-cell group, three mAbs fell within cluster T13 including the CD5a standard b53b7 (No. 174). The two new mAbs 1H6/8 (No. 058) and BB6-9G12 (No. 166) both precipitated 55 and 60 kDa proteins that were of similar molecular weights as the standard. Staining patterns on the various cell types were similar. Both new antibodies inhibited the binding of the CD5a reference mAbs b53b7 to peripheral lymphocytes. These mAbs, therefore both react with the CD5a epitope bringing the number of anti-porcine CD5 mAbs to eight, all of which appear to recognize the same epitope.

Animals↗