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Biomedical subjects

J Serrano

Publications and source records attributed to J Serrano.

At least 127 records · Page 7Linked to original sources
PubMed1997

Malignant pheochromocytoma of the bladder: current controversies.

Urinary bladder pheochromocytoma is an uncommon tumor that produces hypertensive crises coinciding with micturition. It is usually benign, with less than 20 cases with evidence of metastasis described to date. We present a rare case of a malignant bladder pheochromocytoma with regional metastasis, where the pathological and scintigraphic findings are described. The controversy about pathology diagnosis, treatment and prognosis of this unusual tumor is discussed.

3-Iodobenzylguanidine↗
PubMed1997

Growth of newly diagnosed, untreated metastatic gastrinomas and predictors of growth patterns.

PURPOSE: The growth pattern of untreated metastatic neuroendocrine tumors is unknown. This uncertainty contributes to the disagreement regarding timing and could effect evaluation of the efficacy of antitumor treatment. The purpose of this study was to determine the growth rate of untreated hepatic metastatic gastrinoma and to identify its predictors. PATIENTS AND METHODS: Nineteen patients with histologically proven metastatic gastrinoma in the liver with Zollinger-Ellison syndrome were studied. Conventional imaging studies were performed initially and at 4- to 6-month intervals before any treatment. Metastases growth rates were calculated and correlated with laboratory and clinical parameters, as well as tumor extent on initial tumor assessment. RESULTS: Twenty-six percent of patients (five of 19) demonstrated no growth over a mean follow-up time of 29 months, 32% (six of 19) had slow growth (1% to 50% increase in volume per month) over a 19-month period, and 42% (eight of 19) had rapid growth (> 50% volume increase per month) over an 11-month period. In patients with rapid growth, 62% died; 0% of the no-growth or slow-growth group died. No clinical or laboratory parameter correlated with growth rate, except the rate increase in fasting serum gastrin and the presence of bilobar liver or bone metastases. The growth rate was highly predictive of death from tumor. CONCLUSION: The growth rate of metastatic gastrinoma varies markedly in different patients and 26% demonstrate no growth. The growth rate needs to considered in the determination of when and in whom antitumor therapy is initiated, as well as in the assessment of response to tumoricidal therapies.

Adult↗
PubMed1997

[Ulcerative colitis and colonic angiodysplasia associated with a lower digestive hemorrhage. Their diagnosis by 99-technetium-labelled red blood cells].

We describe a case of a patient with previously diagnosed of ulcerative colitis, who was admitted to the hospital because of rectal bleeding and abdominal pain. A mild active colitis was reported by colonoscopy with biopsy. Rectal bleeding relapsed, and an arteriovenous malformation in the transverse colon compatible with angiodysplasia was located by early vascular scintigraphy with 99m-technetium-labeled red blood cells. This finding was confirmed by selective arteriography. Four months after hemicolectomy, the patient is free of rectal bleedings. Labeled red blood cell scintigraphy may be useful to differential diagnosis of lower digestive hemorrhage.

Aged↗
PubMed1997

[Cerebral blood flow study using SPECT in patients with memory disorders].

INTRODUCTION: Global amnesia (AG) is a dysfunction of memory, in which there is a sudden incapacity to remember recent events and assimilate new information. The aetiology is currently under discussion. The main hypotheses under consideration are an ischemic mechanism and an epileptic mechanism. OBJECTIVE: To study the cerebral blood flow in patients with temporary global amnesia (AGT) or permanent global amnesia (AGP) using functional neuroimaging techniques. MATERIAL AND METHODS: Four patients were studied. Two had severe alterations of fixation memory which had been present for months. The other two had a sudden loss of recent memory, although space-person orientation and immediate memory remained normal. In all cases the cerebral blood flow (FSC), was assessed by single photon emission tomography (SPECT), using Tc-HMPAO as the radio tracer. RESULTS: We describe 4 patients, 2 men and 2 women aged between 42 and 64.2 with AGT and the others with AGP. On SPECT there was temporal hypoperfusion in all 4 patients. In 2 cases there was associated parietal hypoperfusion and in 1 case there was frontal hypoperfusion. CONCLUSIONS: These findings suggest that AGT and AGP are of vascular origin and that SPECT is a useful diagnostic technique in patients with AG.

Adult↗
PubMed1997

[Recurrent rectorrhagia caused by angiodysplasia of the colon localized exclusively by scintigraphy with Tc-99m red blood cells].

A case of angiodysplasia of the colon with clinical manifestation of massive rectal bleeding is presented. The activity and the severity of the life-threatening bleeding episode led to emergency exploratory laparotomy with intraoperative colonoscopy which was not diagnostic. Three years later, following multiple recurrent bleeding episodes and non diagnostic explorations, the localization of the hemorrhage was obtained by abdominal scintigraphy with 99mTc-red blood cells. Surgical removal of the affected area achieved definitive cure.

Angiodysplasia↗
PubMed1997

Total-body scintigraphy with thallium-201 and iodine-131 in the follow-up of differentiated thyroid cancer.

UNLABELLED: We analyzed the significance of total body scintigraphy with 201Tl in the follow-up of patients with differentiated thyroid cancer, both in the preablation and ablated stages. METHODS: Prospective assessment was performed in 116 patients who were involved in 178 studies (115 in preablation and 63 after ablation). For ablation, an absence of uptake in the thyroid bed was required in the total 131I follow-up scan after 131I ablation therapy. Each study consisted of a 201Tl scan performed while the patient was receiving thyroid hormone therapy, an 131I scan performed when endogenous thyroid-stimulating hormone levels were higher than 50 mlU/ml and determination of thyroglobulin (Tg) concentration using the same sample. RESULTS: In the 115 scans in the preablation group, the findings for 201Tl and 131I agreed in 26 scans and disagreed in 89 scans. In 59 discordant studies, only 131I detected focal accumulation, and, in 54 of these, Tg levels were undetectable. Of the other 30 discordant studies, 201Tl and 131I detected focal uptake in 27 studies, although they did not reveal the same lesions, and in 3 studies, only 201Tl detected focal accumulation; in these 30 studies, the association of detectable Tg predominated. Of the 63 studies in the ablated group, the results agreed for the two tracers in 49 and disagreed in 14 studies. In 13 of the 14 discordant studies, 201Tl detected focal uptake, and, in 10 of these, Tg was detectable. Thus, 31 of the 116 patients assessed (15 preablation and 16 ablated) had at least one lesion that was detected by 201Tl but not detected by 131I. A definitive diagnosis could be established in 26 patients, and the presence of thyroid cancer was confirmed in 23. The sensitivity and specificity in the ablated group were 94% and 96%, respectively, for 201Tl and 29% and 100%, respectively, for 131I. CONCLUSION: The high sensitivity of 201Tl scintigraphy in detecting tumor tissue indicates that the inclusion of this technique in the follow-up of patients with differentiated thyroid carcinoma should be considered in both the preablation and the ablated stages.

Adenocarcinoma, Follicular↗
PubMed1996

Determination of 8-hydroxydeoxyguanosine in biological tissue by liquid chromatography/electrospray ionization-mass spectrometry/mass spectrometry.

A method based on liquid chromatography (LC) combined with electrospray ionization tandem mass spectrometry for the analysis of the frequency of formation of 8-hydroxydeoxyguanosine (80HdGuo), a biomarker of oxidative damage to DNA, has been developed. This analytical technique has the advantage over gas chromatography combined with mass spectrometry of not requiring analyte derivatization, and over LC combined with ultraviolet and electrochemical detection of being chemospecific. The method was evaluated by determining increased frequency of formation of 80HdGuo in male Sprague-Dawley rats given a single intraperitoneal dose of Adriamycin compared to control rats. Detection of one oxidized deoxyguanosine per 5 x 10(5) deoxyguanosines was readily achieved.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed1996

Effects of L-arginine infusion on renal hemodynamics and sodium excretion during hypo-, normo-, and hyperinsulinemia, as studied in dogs.

The response of renal hemodynamics and sodium excretion (NaU) to an infusion of L-arginine, in the presence (experiment I) or absence (experiment II) of endogenous insulin secretion and during a sustained hyperinsulinemic euglycemic state (experiment III), was studied in 10 age-matched beagle dogs. The experiments were preceded by a standard oral glucose tolerance test (OGTT), performed 1 week before experiment I. One week resting periods were allowed between experiments I, II, and III. No differences in renal hemodynamics and NaU were observed between basal (experiment I) and insulin secretion suppressed states (experiment II). L-Arginine infusion increased renal plasma flow (RPF), glomerular filtration rate (GFR), and NaU to a similar extent in both experiments. The hyperinsulinemic-euglycemic state (experiment III) induced a decrease in renal hemodynamics and NaU. In this situation, the infusion of L-arginine increased NaU, but was unable to increase RPF and GFR. Our data suggest that a sustained hyperinsulinemic state can interact with the physiological vasoactive mechanisms involved in the regulation of renal vasculature. These results may be pertinent to human disease, especially in pathological conditions in which insulin resistance is present.

6-Ketoprostaglandin F1 alpha↗
PubMed1996

[Bronchiolitis associated with ulcerative colitis].

Inflammatory bowel disease (IBD) only occasionally affects the lung. Noteworthy among the various pulmonary entities related to IBD are chronic bronchitis and bronchiectasis, though reports of bronchiolitis, obliterants bronchiolitis with organizing pneumonia and other interstitial diseases have also been published. Given the rarity of such pneumopathy, we report a case of bronchiolitis in a patient with a prior diagnosis of ulcerative colitis. We discuss the radiological findings and the results of lung function testing, emphasizin the utility of corticosteroid treatment, which usually leads to a good outcome in pneumopathy secondary to IBD.

Administration, Oral↗
PubMed1995

Protein kinase C is increased in the liver of humans and rats with non-insulin-dependent diabetes mellitus: an alteration not due to hyperglycemia.

We tested the hypothesis that liver protein kinase C (PKC) is increased in non-insulin-dependent diabetes mellitus (NIDDM). To this end we examined the distribution of PKC isozymes in liver biopsies from obese individuals with and without NIDDM and in lean controls. PKC isozymes alpha, beta, epsilon and zeta were detected by immunoblotting in both the cytosol and membrane fractions. Isozymes gamma and delta were not detected. There was a significant increase in immunodetectable PKC-alpha (twofold), -epsilon (threefold), and -zeta (twofold) in the membrane fraction isolated from obese subjects with NIDDM compared with the lean controls. In obese subjects without NIDDM, the amount of membrane PKC isozymes was not different from the other two groups. We next sought an animal model where this observation could be studied further. The Zucker diabetic fatty rat offered such a model system. Immunodetectable membrane PKC-alpha, -beta, -epsilon, and -zeta were significantly increased when compared with both the lean and obese controls. The increase in immunodetectable PKC protein correlated with a 40% elevation in the activity of PKC at the membrane. Normalization of circulating glucose in the rat model by either insulin or phlorizin treatment did not result in a reduction in membrane PKC isozyme protein or kinase activity. Further, phlorizin treatment did not improve insulin receptor autophosphorylation nor did the treatment lower liver diacylglycerol. We conclude that liver PKC is increased in NIDDM, a change that is not secondary to hyperglycemia. It is possible that PKC-mediated phosphorylation of some component in the insulin signaling cascade contributes to the insulin resistance observed in NIDDM.

Adult↗
PubMed1995

Alpha 1-adrenoceptor reagents. Synthesis of some 5,6,11,11a-tetrahydro-1H-imidazo[1',5':1,6]pyrido and 5,6,11,11b-tetrahydro-1H-imidazo[1',5':1,2]pyrido[3,4-b]indole-1,3(2H) -diones.

Several 2-substituted 5,6,11,11a-tetrahydro-1H-imidazo[1',5':1,6]pyrido (1) and 5,6,11,11b-tetrahydro-1H-imidazo [1',5':1,2]pyrido[3,4-b]indole,3(2H)-diones (2) were synthesized and studied by 2D-NMR spectroscopy and difference nuclear Overhauser effect experiments. All the compounds were evaluated for in vitro alpha(1) adrenoceptor affinity by radioligand receptor binding assays. The most active derivative in displacement of [3H]prazosin from rat cortical membranes was 1b (K(i) = 219 nM). At 1 microM concentration, compounds 1 and 2 had no effect on the benzodiazepine or 5-HT(1A) receptor. The biological activity profile of 1b makes it a possible lead compound for the design of new selective alpha1 adrenoceptor ligands.

Animals↗
PubMed1995

CT findings of atrophy of chest wall muscle after thoracotomy: relationship between muscles involved and type of surgery.

OBJECTIVE: Postthoracotomy atrophy of chest wall muscles results from nerve injury during surgery. After encountering patients with different patterns of chest wall muscular atrophy postthoracotomy, we performed this study to determine the relationship between type of thoracotomy and atrophic muscles as seen on CT scans. MATERIALS AND METHODS: CT scans of 58 patients who had previously undergone unilateral thoracotomy were reviewed. Forty patients had a posterolateral thoracotomy, and 18 had an anterolateral thoracotomy. In two cases, the incision extended posteriorly. Atrophy seen on CT scans was defined as a marked decrease in size or thickness of a muscle compared with the muscle on the other side. RESULTS: Atrophy of the latissimus dorsi muscle and of the inferior portion of the serratus anterior muscle was detected on CT scans in 40 patients. No atrophy was found in 16 patients. The remaining two displayed atrophy only in the serratus anterior muscle. Atrophy of the latissimus dorsi muscle and of the inferior portion of the serratus anterior muscle developed in all patients who had a posterolateral thoracotomy. Atrophy developed in only two of the 18 patients who had an anterolateral thoracotomy, and in these two, the incision had been extended posteriorly. CONCLUSION: A direct correlation was found between type of thoracotomy and site of atrophy of the chest wall muscles seen on CT scans. This finding may account for different CT appearances of the thoracic wall in patients who have had thoracic surgery.

Aged↗
PubMed1995

[Surgery for the repair of renal arteriovenous fistula and its hemodynamic impact].

The case of a 42-year-old woman with an arteriovenous fistula on the left kidney is described. Twenty-six years before presentation, a percutaneous renal biopsy had been obtained. The patient presented with arterial hypertension, angina and dyspnea. We studied the hemodynamic parameters before and after surgical repair of the fistula. Pulmonary artery pressure was very high but fell to normal after surgery, indicating that the fistula was responsible for hemodynamic complications that increased the level of surgical risk.

Adult↗
PubMed1995

[Carotid endarterectomy using cervical plexus block].

To evaluate the efficacy and level of patient satisfaction, as well as the incidence of neurological manifestations, hemodynamic changes and other perioperative complications of cervical plexus block. This was a prospective study of 52 patients undergoing carotid endarterectomy under superficial and deep cervical plexus block. The anesthetic technique was effective in all cases. Supplementation with local anesthetic was needed for 25% of the patients and none required general anesthesia. The technique was considered good by 92% of the patients, who stated that would accept the same technique in case of having to undergo surgery on the contralateral carotid artery. Hypertension was the hemodynamic change observed most often (in 30%) during surgery. No serious complications related to the anesthetic technique were observed, though transient dysphonia was the most frequently seen effect (in 36.5%). Eight (15.4%) patients showed neurological signs when the carotid was clamped, with symptoms resolving with placement of a shunt. Two deaths due to myocardial infarction occurred after surgery and 1 patient suffered a permanent cerebrovascular accident. Regional anesthesia with deep and superficial cervical plexus block during carotid endarterectomy allows for continuous evaluation of the patient's neurological status and facilitates the selective use of intraluminal shunt for the prevention of stroke accident during surgery. The technique is well-tolerated by patients, does not make surgery more difficult, does not give rise to serious complications and the incidence of local complications is low.

Aged↗
PubMed1993

Analytical procedures and quality assurance criteria for the determination of major and minor deoxynucleosides in fish tissue DNA by liquid chromatography-ultraviolet spectroscopy and liquid chromatography-thermospray mass spectrometry.

Analytical procedures and quality assurance criteria have been established for enzymatic hydrolysis of fish tissue DNA to free nucleosides and their subsequent characterization by liquid chromatography-photodiode-array ultraviolet spectroscopy and liquid chromatography-thermospray mass spectrometry. Optimization of enzymatic efficiency to assure minimal loss of modified nucleosides is described. Variability in analyte capacity factors and multiwavelength response have been compared for analyte standards and hydrolysates, and results have been used to derive qualitative and quantitative quality assurance criteria. A comparison of DNA mole percent calculated using single-wavelength quantification and multiwavelength averaging quantification indicates that less variability in data may be expected using the multiwavelength technique. Finally, the composition of DNA from liver of three species of fish widely used in mutagen/carcinogen laboratory and field studies, rainbow trout (Onchorynchus mykiss), medaka (Oryzias latipes), and brown bullhead (Ictalurus nebulosus), has been determined. Identification of deoxyuridine in the DNA hydrolysates of each fish indicates that this analyte should be measured to accurately report DNA deoxynucleoside mole percent, especially when reporting data for the methylation of deoxycytidine.

Animals↗
PubMed1993

A novel chicken homeobox-containing gene expressed in neurulating embryos.

We have isolated a cDNA clone from chicken embryo that contains a homeobox sequence (CHox-cad2). Analysis at the nucleotide and amino acid levels revealed closest similarity to the Xenopus Xcad1 and to other homeoboxes related to Drosophila caudal. RNA blot analysis showed hybridization of CHox-cad2 to two transcripts of 2.6 and 1.5 kb, present at day 1 of embryogenesis (E1). Using the highly sensitive polymerase chain reaction (PCR) to amplify cDNAs from embryonic RNAs from E0 (unincubated blastoderm) to E4, we confirmed the restricted expression of this homeobox sequence to the period of neurulation (E1).

Amino Acid Sequence↗