[Unusual form of initiation of diabetes mellitus in patient with treatment refractory arterial hypertension].
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to J Estrada.
Explore the source record for details and available documents.
OBJECT: The indications for additional radiotherapy (RT) after surgery for non-functioning pituitary adenoma are controversial. The goal of this retrospective study was to evaluate the outcome of surgically treated patients, with or without post- operative irradiation. METHODS: Review of cases treated for non-functioning pituitary adenoma. Fifty-one patients were identified, with a mean post-operative follow-up of 6.4+/-3.5 yr. Twenty-nine patients showed residual tumor after surgery and 22 did not. Serial endocrine, visual and radiological evaluations were made after treatment to assess the efficacy and toxicity of surgery and RT. Twenty-seven patients with residual tumor after surgery received RT (22 of them during the post-operative period and 5 after an interval of several yr: 3 because of increased tumor size and 2 with stable residual lesion); tumors in 14 of these patients decreased in size, 11 appeared to be stable on imaging and one patient showed some increase in tumor size (one patient was not followed-up). The residual tumors of the 2 non-irradiated patients remained stable after 5 and 7 yr, respectively. Twenty-two patients without residual disease after surgery (11 with post-operative irradiation, 1 with RT 5 yr after transsphenoidal surgery because of tumor recurrence, and 10 without RT) have shown no evidence of tumor regrowth on serial images. CONCLUSIONS: Radiotherapy can be avoided in patients with complete macroscopic resection and absence of residual tumor in post-operative images; they must be carefully followed using imaging techniques and, in the case of recurrence, they should be re-operated and/or irradiated.
The development of Cushing's disease among patients with deficiency of 21-hydroxylase has not been observed to date. The clinical manifestations and the hormonal profile of this exceptional association are herein described through the study of two cases. The first one was a 39-yr-old woman who had undergone non-curative transsphenoidal surgery for a pituitary-dependent Cushing's syndrome 12 yr before. She showed hypertension, central obesity, severe hirsutism, alopecia and hyperpigmentation. Urinary excretion of cortisol was normal, but ACTH levels were very high and hormonal dynamic studies (cortisol circadian rhythm, insulin-induced hypoglycemia and dexamethasone suppression tests) revealed the qualitative disturbances that characterize Cushing's disease. Serum concentrations of androstenedione, free testosterone and 17-hydroxyprogesterone were clearly increased. Reexamination of the tissue samples from previous surgery confirmed the presence of an ACTH-producing pituitary adenoma. CYP21 gene analysis found the splicing 655G mutation at intron 2 and the V281L mutation at exon 7. The second case was a 21-yr-old woman who was diagnosed with pituitary ACTH-dependent Cushing's syndrome according to unequivocal clinical and laboratory findings. However, hirsutism was particularly severe and both serum androgens and 17-hydroxyprogesterone were elevated. The patient was heterozygote for a large conversion of CYP21 gene. In these cases, the clinical and biochemical expression of Cushing's syndrome was determined by the different severity of 21-hydroxylase deficiency and the subsequent residual ability of adrenal cortex to synthesize cortisol.
The landmark discrimination learning test can be used to assess the ability to utilize allocentric spatial information to locate targets. The present experiments examined the role of various factors on performance of a landmark discrimination learning task in beagle dogs. Experiments 1 and 2 looked at the effects of age and food composition. Experiments 3 and 4 were aimed at characterizing the cognitive strategies used in performance on this task and in long-term retention. Cognitively equivalent groups of old and young dogs were placed into either a test group maintained on food enriched with a broad-spectrum of antioxidants and mitochondrial cofactors, or a control group maintained on a complete and balanced food formulated for adult dogs. Following a wash-in period, the dogs were tested on a series of problems, in which reward was obtained when the animal responded selectively to the object closest to a thin wooden block, which served as a landmark. In Experiment 1, dogs were first trained to respond to a landmark placed directly on top of coaster, landmark 0 (L0). In the next phase of testing, the landmark was moved at successively greater distances (1, 4 or 10 cm) away from the reward object. Learning varied as a function of age group, food group, and task. The young dogs learned all of the tasks more quickly than the old dogs. The aged dogs on the enriched food learned L0 significantly more rapidly than aged dogs on control food. A higher proportion of dogs on the enriched food learned the task, when the distance was increased to 1cm. Experiment 2 showed that accuracy decreased with increased distance between the reward object and landmark, and this effect was greater in old animals. Experiment 3 showed stability of performance, despite using a novel landmark, and new locations, indicating that dogs learned the landmark concept. Experiment 4 found age impaired long-term retention of the landmark task. These results indicate that allocentric spatial learning is impaired in an age-dependent manner in dogs, and that age also affects performance when the distance between the landmark and target is increased. In addition, these results both support a role of oxidative damage in the development of age-associated cognitive dysfunction and indicate that short-term administration of a food enriched with supplemental antioxidants and mitochondrial cofactors can partially reverse the deleterious effects of aging on cognition.
A case of multiple endocrine neoplasia syndrome type-2A (MEN-2A) with primary hyperparathyroidism and medullary carcinoma of thyroid initially treated by surgery is reported. The presence of pulmonary nodules six years after the initial treatment was thought to be related to metastasis of medullary carcinoma, and the increase in serum calcium concentrations was assumed to be caused by persistence of parathyroid adenomatous or hyperplastic tissue. The patient underwent surgery again and the pulmonary nodules were confirmed to be metastases of a parathyroid carcinoma, a very rare entity in MEN-2A syndrome.
The D0 Collaboration has measured the inclusive jet cross section in barpp collisions at square root of s = 630 GeV. The results for pseudorapidities (eta)<0.5 are combined with our previous results at square root of s = 1800 GeV to form a ratio of cross sections with smaller uncertainties than either individual measurement. Next-to-leading-order QCD predictions show excellent agreement with the measurement at 630 GeV; agreement is also satisfactory for the ratio. Specifically, despite a 10% to 15% difference in the absolute magnitude, the dependence of the ratio on jet transverse momentum is very similar for data and theory.
We report on a study of the ratio of inclusive three-jet to inclusive two-jet production cross sections as a function of total transverse energy in p&pmacr; collisions at a center-of-mass energy sqrt[s] = 1.8 TeV, using data collected with the D0 detector during the 1992-1993 run of the Fermilab Tevatron Collider. The measurements are used to deduce preferred renormalization scales in perturbative O(alpha(3)(s)) QCD calculations in modeling soft-jet emission.
We report a search for effects of large extra spatial dimensions in pp collisions at a center-of-mass energy of 1.8 TeV with the D0 detector, using events containing a pair of electrons or photons. The data are in good agreement with the expected background and do not exhibit evidence for large extra dimensions. We set the most restrictive lower limits to date, at the 95% C.L. on the effective Planck scale between 1.0 and 1.4 TeV for several formalisms and numbers of extra dimensions.
Explore the source record for details and available documents.
Transsphenoidal microsurgery is the standard treatment for patients with Cushing's disease. However, there is general lack of agreement regarding the definition of cure. We studied 58 patients with corrected hypercortisolism after transsphenoidal surgery for Cushing's disease. Plasma and urinary cortisol levels were measured after surgery. After the postsurgical hypocortisolism stage (or periodically in patients without hypocortisolism), urinary free cortisol, plasma cortisol at 0800 h and 2300 h, morning cortisol after 1 mg dexamethasone, and cortisol response to insulin-induced hypoglycemia were performed. Patients were classified in 3 groups: group I, patients with transient hypocortisolism and normal hypothalamus-pituitary-adrenal axis afterwards; group II, patients with transient hypocortisolism and abnormalities in the circadian rhythm or the stress response afterwards; and group III, patients without postoperative hypocortisolism. Thirty-three patients were included in group I, 8 in group II, and 17 in group III. Groups I and II were similar in postsurgical plasma cortisol (46.9 +/- 30.3 vs. 60.7 +/- 38.6 nM) and mean follow-up (69.8 vs. 68.8 months) but were significantly different in their recurrence rate (3.4% vs. 50%, P < 0.001). Patients in group III had normal postsurgical plasma and urinary cortisol but persistent abnormalities in circadian rhythm and stress response. After a mean follow-up of 39.1 months, their recurrence rate was similar to that of group II (64.7% vs. 50%). The complete normalization of the adrenocortical function, which is always preceded by postsurgical hypocortisolism, is associated with a very low recurrence risk and should be considered, in our opinion, the main criterion of surgical cure in Cushing's disease.
We report on a measurement of sigma(pp-->W+X)B(W-->taunu) in pp collisions at sqrt[s]=1.8 TeV at the Fermilab Tevatron. The measurement is based on an integrated luminosity (lum) of 18 pb-1 of data collected with the D0 detector during 1994-1995. We find that sigma(pp-->W+X)B(W-->taunu)=2.22+/-0.09 (stat)+/-0. 10 (syst)+/-0.10 (lum) nb. Lepton universality predicts that the ratio of the tau and electron electroweak charged current couplings to the W boson, gWtau/gWe, be unity. We find gWtau/gWe=0.980+/-0.031, in agreement with lepton universality.
Inclusive dijet production at large pseudorapidity intervals (Deltaeta) between the two jets has been suggested as a regime for observing Balitsky-Fadin-Kuraev-Lipatov (BFKL) dynamics. We have measured the dijet cross section for large Deltaeta in pp collisions at sqrt[s]=1800 and 630 GeV using the D0 detector. The partonic cross section increases strongly with the size of Deltaeta. The observed growth is even stronger than expected on the basis of BFKL resummation in the leading logarithmic approximation. The growth of the partonic cross section can be accommodated with an effective BFKL intercept of alphaBFKL(20 GeV)=1.65+/-0.07.
Magnetized Rydberg positronium forms when an energetic positron ( e(+)) slows within a tungsten crystal and picks up an electron ( e(-)) as it emerges in a strong magnetic field. The signature is equal numbers of e(+) and e(-) when a weak electric field is applied, either of which can be accumulated and counted. The new e(+) accumulation technique is simple, robust, and much more efficient than any other demonstrated to be compatible with a cryogenic vacuum. Possible applications include the study of cold single component plasmas of e(+) and the formation of cold antihydrogen.
Apolipoprotein E (APOE) genotypes were determined in 75 Mazatecan Indians and 83 Mexican mestizos. APOE allele and genotype frequencies in Mazatecans and mestizos were similar, with high frequencies of the APOE*3 allele (0.900 and 0.915, respectively) and the E3/3 genotype (0.813 and 0.831, respectively) and an absence in both samples of the APOE*2 allele. Our data are similar to those previously described for Mexican-American and Mayan populations, which show the highest frequency worldwide of the APOE*3 allele and the E3/3 genotype. Mazatecans and mestizos also show a decreased frequency of the APOE*4 allele when compared to other Amerindian groups. The absence of the APOE*2 allele has also been reported in other Amerindian groups such as Mayans and Cayapa, whereas in Caucasians the average frequency of this allele is about 8%. Our data are in agreement with previous reports showing absence of the APOE*2 allele in Native American groups. These findings suggest that the APOE*2 allele was absent in humans from northern Asia who settled in the Arctic and populated the American continent.
Mnemonic deficits resulting from excitotoxic lesion of the basal forebrain have been classically attributed to the resulting depletion of cortical acetylcholine activity. In this study, we have performed a detailed analysis of the cholinergic status of the insular cortex (IC) following local injections of either 192IgG-saporin (192IgG-sap) or N-methyl-D-aspartate (NMDA) directly into the nucleus basalis magnocellularis (NBM). By means of in vivo microdialysis, we show that the immunotoxin lesion results in an almost complete lack of extracellular acetylcholine release, whereas NMDA-induced lesions result in a marginal reduction in cortical cholinergic activity. Choline-acetyltransferase activity in the IC further confirmed this differential pattern of cortical deafferentation. Surprisingly, however, only NMDA-induced lesions showed a strong disruptive effect upon taste aversion learning whereas no detectable deficits could be found following 192IgG-sap lesions. By combining intrabasal injections of 192IgG-sap with acute pre-training infusions of the cholinergic antagonist scopolamine into the IC, a strong disruption of taste aversion was attained. These results imply that residual cholinergic activity, following 192IgG-saporin lesions, might be still critical for normal cortical mediation of memory processing. They also support the role of basal forebrain in mediating learning and memory processes, and demonstrate that mnemonic deficits resulting from excitotoxic lesions of the basal forebrain are not the sole result of cortical acetylcholine activity hypofunction.
OBJECTIVE: To determine the clinical spectrum of disease in humans with mutations in the CD95 (Fas/ APO-1) receptor and to obtain mechanistic insight into the different clinical phenotypes observed. METHODS: Clinical information for each of the index cases, first-degree relatives, and any family members reported to have Canale-Smith syndrome (or another autoimmune disease) was gathered by direct interview, chart review, and verification of data by the physician or pathologist concerned. Apoptosis of activated T or B lymphocytes was induced by agonistic anti-CD95 antibodies and quantified by a cell death assay (propidium iodide staining in the subdiploid peak) or cell viability assay (alamar blue or 3H-thymidine incorporation). RESULTS: Evaluation of an additional 8 probands with novel heterozygous CD95 mutations revealed hypergammaglobulinemia and immune-mediated cytopenias in all patients, as well as urticarial rash, oral ulceration, lymphopenia, and peripheral neuropathy in some individuals. One patient (P4) had systemic lupus erythematosus (SLE) characterized by a World Health Organization class V lupus nephropathy, a recurrent, reversible multifocal central nervous system disorder, high-titer antiphospholipid autoantibodies, and autoimmune cytopenias. In the P4 pedigree, the father had reduced T and B cell apoptosis associated with a CD95 mutation, whereas an independent B cell apoptotic defect was demonstrated in maternal family members who did not have a CD95 mutation. Three cases of B cell lymphoma occurred in carriers of the CD95 mutation. CONCLUSIONS: CD95 mutations are associated with loss of regulation of B lymphocytes, which predisposes to systemic autoimmunity including SLE. The P4 family provides a model of the complex genetic and functional interactions that are required for the development of a lupus-like syndrome.
BACKGROUND: Irradiation of the pituitary is widely considered the most appropriate treatment for patients with Cushing's disease in whom transsphenoidal microsurgery has been unsuccessful. However, there is little information about the long-term efficacy of this treatment. METHODS: We used external pituitary radiation to treat 30 adult patients with persistent or recurrent Cushing's disease after unsuccessful transsphenoidal surgery. The mean (+/-SD) dose of radiation was 50+/-1 Gy. Pituitary and adrenal function was assessed every six months after radiation therapy. Remission was defined as the regression of symptoms and signs of Cushing's syndrome, normal urinary cortisol excretion, and a low plasma cortisol concentration in the morning after the administration of 1 mg of dexamethasone at midnight. RESULTS: Twenty-five patients (83 percent) had remissions during a median follow-up of 42 months (range, 18 to 114). The remissions began 6 to 60 months after radiation therapy, but in most cases (22 patients) remission occurred during the first 2 years. None of the 25 patients had a relapse of Cushing's disease after remission was achieved. There was no relation between the response to radiotherapy and sex, age, urinary cortisol excretion before radiotherapy, the interval between surgery and radiotherapy, whether a pituitary adenoma was found by pathological examination, or tumor size. Seventeen patients had a deficiency of growth hormone after radiation therapy, 10 had a deficiency of gonadotropins, 4 had a deficiency of thyrotropin, and 1 had a deficiency of corticotropin. CONCLUSIONS: Pituitary irradiation is an effective and well-tolerated treatment for patients with Cushing's disease in whom transsphenoidal surgery is unsuccessful.
We describe a patient with an incidental adrenal myelolipoma associated with biochemical evidence of Cushing's syndrome who lacked the physical stigmata of cortisol excess (subclinical Cushing's syndrome). Pathologic examination revealed the presence of adrenocortical cells mixed with myelolipomatous tissue. Although cases of clinically evident Cushing's syndrome due to adrenal myelolipomas have been reported previously, to our knowledge this is the first report associating adrenal myelolipoma and subclinical Cushing's syndrome.