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R Robles

Publications and source records attributed to R Robles.

At least 73 records · Page 4Linked to original sources
PubMed2000

Clinical and histological differences in anaplastic thyroid carcinoma.

OBJECTIVE: To report our experience in patients with anaplastic thyroid carcinoma and try to establish differences between cases in which the histological study showed that there was an associated thyroid carcinoma and those that were strictly anaplastic or pure. DESIGN: Retrospective study. SETTING: University hospital, Spain. SUBJECTS: 14 patients with anaplastic thyroid cancer treated over a period of 26 years; 7 presented with associated thyroid tumours and 7 were pure. MEAN OUTCOME MEASURES: Clinical data (age, sex, symptoms), treatment, histological study (associated thyroid disease, spread, involved lymph nodes) and follow-up. RESULTS: 13 of the 14 tumours had spread locally. 5 patients were treated by total thyroidectomy, 3 subtotal thyroidectomy, 5 excision of the tumour, and 1 patient had a biopsy alone. There were associated thyroid tumours in 7 cases: 2 follicular, 2 tall cell papillary, 1 solid papillary, 1 medullary and 1 Hurthle cell tumour. 12 patients died. Another 2 are still alive having survived 61 and 70 months respectively, both with associated anaplastic cancers (follicular and solid). The mean survival was 14 months (24 for associated anaplastic carcinoma and 4 for pure anaplastic carcinoma). CONCLUSION: There is a subgroup of anaplastic cancers in which a better differentiated thyroid carcinoma coexists with the anaplastic carcinoma. The prognosis in this subgroup is better than that for primary pure anaplastic carcinoma.

Adult↗
PubMed2000

The aryl hydrocarbon receptor, a basic helix-loop-helix transcription factor of the PAS gene family, is required for normal ovarian germ cell dynamics in the mouse.

The aryl hydrocarbon receptor (AhR), so-designated based on the ability of the protein to bind with and be activated by polycyclic aromatic hydrocarbons (PAH) and related halogenated hydrocarbons, is part of an emerging family of ligand-activated transcriptional regulators that are distinct from the steroid-thyroid hormone receptor superfamily. Once bound by ligand, the AhR interacts with the AhR nuclear translocator (ARNT) protein to form the aryl hydrocarbon receptor complex (AHRC). Both subunits of the AHRC contain sequences corresponding to basic helix-loop-helix domains, a motif that is shared by a number of other dimeric transcription factors. Although the natural ligand(s) for the AhR remains to be elucidated, to date over fifteen genes, including enzymes, growth factors and other transcription factors, have been identified as potential targets for transcriptional regulation by the chemically-activated AHRC. In the ovary, PAH exposure is known to cause destruction of oocytes within immature follicles, implying that one function of the AhR is to mediate cell death signaling in the female germ line. To assess this possibility, we explored AhR expression patterns in the murine ovary, and then determined the impact of AhR-deficiency (gene knockout) on female germ cell dynamics. Immunohistochemical analysis of ovaries of wild-type female mice indicated that AhR protein was abundantly and exclusively expressed in oocytes and granulosa cells of follicles at all stages of development. Histomorphometric analysis of serial ovarian sections revealed a two-fold higher number of primordial follicles in Ahr-null versus wild-type females at day 4 postpartum. This phenotype likely results from a cell-intrinsic death defect in the developing germ line since AhR-deficiency attenuated the magnitude of oocyte apoptosis in fetal ovaries cultured without hormonal support for 72 h. We propose that the AhR, activated by an as yet unknown endogenous ligand(s), serves to regulate the size of the oocyte reserve endowed at birth by affecting germ cell death during female gametogenesis.

Animals↗
PubMed1999

Analysis of the complications of the piggy-back technique in 1,112 liver transplants.

BACKGROUND: The "piggy-back" technique has gained acceptance in adult orthotopic liver transplantation during the last few years, especially in European countries. At the moment, however, there is controversy over advantages or specific complications (suprahepatic thrombosis or narrowing, etc.) related to this surgical technique. The aim of this study is to know of the immediate per-and postoperative morbidity and mortality rates in 1112 orthotopic liver transplantations performed with a vena cava preservation technique. METHODS: All liver transplant units in Spain were sent a questionnaire on retrohepatic vena cava preservation during orthotopic liver transplantation. The number of orthotopic liver transplantations that had been performed in the seven centers that answered the questionnaire, because the beginning of the program, was 1674, with the vena cava preservation technique used in 1112. RESULTS: Twenty-eight patients (2.5%) had intraoperative complications related to the vena cava preservation technique, which were treated during the operation. Eleven patients (1%) had early postoperative complications (first week), the most frequent (nine cases) being an acute Budd-Chiari syndrome in the first 48 hr. Three patients developed symptoms of massive ascites between 2 and 3 months (late postoperative complications), with patency of the retrohepatic cava verified by cavography. A hemodynamic study revealed a hyperpressure at the suprahepatic veins. This chronic Budd-Chiari syndrome was controlled in all patients with diuretics. Only six patients (0.5%) died as a result of complications related to the "piggy-back" technique. These complications were more frequent when venous reconstruction was done using two suprahepatic veins than when the three veins were used (P<0.001). CONCLUSIONS: The vena cava preservation technique can be used routinely in orthotopic liver transplantation because it is safe and efficient and involves few surgical complications especially if for venous reconstruction we use the patch obtained by joining the three suprahepatic veins.

Adult↗
PubMed1999

Effect of antiviral drugs used to treat cytomegalovirus end-organ disease on subsequent course of previously diagnosed Kaposi's sarcoma in patients with AIDS.

OBJECTIVE: To evaluate the association of ganciclovir (GCV) and foscarnet (PFA) therapy with the outcome of previously diagnosed Kaposi's sarcoma (KS) after initiating antiviral therapy for cytomegalovirus (CMV) end-organ disease. DESIGN: Retrospective study. METHODS: KS progression was defined as a clinically obvious increase in size of baseline cutaneous or mucosal lesions, a new diagnosis of visceral KS, or initiation of a new systemic antineoplastic regimen or radiation therapy to treat KS. Multivariate analyses of risk of KS progression were calculated for prior duration of KS before initiating CMV treatment, treatment with PFA or GCV, number of weeks treated with PFA or GCV, absolute CD4 lymphocyte count at time of CMV-related disease diagnosis, diagnosis of KS prior to 1991, visceral KS, prior systemic chemotherapy, and prior radiation therapy. RESULTS: Among 66 patients who received > or = 14 days PFA (N=20) or only GCV (N=46), median time to progression of KS was 211 days (95% confidence interval [CI], 46-578) for patients who received PFA versus 22 days (95% CI, 15-41) for those who received only GCV (p < .001). In the stepwise multivariate analysis, only prior visceral KS (rate ratio [RR]=2.80; 95% CI, 1.07-7.35) and foscarnet therapy (RR = 0.24; 95% CI, 0.11-0.53) were significantly associated with risk of KS progression. CONCLUSION: PFA may be an effective therapy for AIDS-related KS; prospective trials are indicated.

Acquired Immunodeficiency Syndrome↗