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Biomedical subjects

E Castro

Publications and source records attributed to E Castro.

At least 55 records · Page 3Linked to original sources
PubMed1995

Treatment of pulmonary disease caused by Mycobacterium kansasii: results of 18 vs 12 months' chemotherapy.

SETTING: Chest Clinic, Sant Pau Hospital, Barcelona, Spain. OBJECTIVE: To assess the therapeutic response of pulmonary disease due to Mycobacterium kansasii to 12 and 18 months of chemotherapy. DESIGN: 28 patients with criteria of pulmonary disease caused by M. kansasii not associated with HIV-infection were identified in our department in the period 1985-91 (24 male, 4 female, mean age 56 +/- 12 years). 14 patients were treated with rifampicin-isoniazid-ethambutol daily for 12 months (ethambutol only for the first 6 months), and 14 with the same regimen for 18 months. The follow-up after treatment was 12-30 months. RESULTS: All patients showed improvement of radiographic manifestation of disease and sputum conversion (mean time: 4.5 +/- 2 months). The adverse drug effects were minimal. No failures were detected, and only one patient (3.5%), in the group of 12-month chemotherapy, relapsed after finishing the treatment. CONCLUSIONS: Our findings suggest that pulmonary disease due to M. kansasii has an effective response to 12-month chemotherapy regimen and that it is not necessary to prolong the administration of ethambutol for more than 6 months.

Adult↗
PubMed1995

5'-(N-ethylcarboxamido)adenosine inhibits Ca2+ influx and activates a protein phosphatase in bovine adrenal chromaffin cells.

We investigated the effect of the adenosine receptor agonist 5'-(N-ethylcarboxamido)adenosine (NECA) in catecholamine secretion from adrenal chromaffin cells that exhibit only the A2b subtype adenosine receptor. NECA reduced catecholamine release evoked by the nicotinic agonist 1,1-dimethyl-4-phenylpiperazinium (DMPP) in a time-dependent manner. Inhibition reached 25% after 30-40-min exposure to NECA. This effect on DMPP-evoked catecholamine secretion was mirrored by a similar (27.7 +/- 3.3%), slowly developing inhibition of [Ca2+]i transients induced by DMPP that peaked at 30-min preincubation with NECA. The capacity of the chromaffin cells to buffer Ca2+ load was not affected by the treatment with NECA. Short-term treatment with NECA failed both to modify [Ca2+]i levels and to increase endogenous diacylglycerol production, showing that NECA does not activate the intracellular Ca2+/protein kinase C signaling pathway. The inhibitory effects of NECA were accompanied by a 30% increase of protein phosphatase activity in chromaffin cell cytosol. We suggest that dephosphorylation of a protein involved in DMPP-evoked Ca2+ influx pathway (e.g., L-type Ca2+ channels) could be the mechanism of the inhibitory action of adenosine receptor stimulation on catecholamine secretion from adrenal chromaffin cells.

Adenosine↗
PubMed1995

[Recombinant growth hormone for support of ovarian gonadotropin treatment in a hypophysectomized patient: a case-control study].

In a patient, suffering of apituitarism after the surgical removal of a cranyopharyngeoma at the age of 14, was treated with various doses of human urinary gonadotropin preparations for in vitro fertilization and embryo transfer. The first five treatments were performed without the additional administration of recombinant growth hormone, but due to the administration of increasing doses of exogenous gonadotropins a pregnancy was finally achieved leading to the birth of a healthy girl. Later, as the couple desired a second baby, the treatment was repeated using a low dose of gonadotropins in combination with recombinant growth hormone. This combined treatment was immediately successful, leading to the birth of a healthy boy. The present communication offers a complete survey of the existing literature about the use of recombinant growth hormone in support of ovarian stimulation with gonadotropins. The ongoing controversy is caused by the lack of an established methodology for the diagnosis of growth hormone deficiency. Whereas the efficacy of the additional use of recombinant growth hormone in support of ovarian stimulation with gonadotropins is established in patients without any endogenous growth hormone secretion, its use in patients with less defined hormonal disturbances remains controversial.

Adult↗
PubMed1995

[Value and role of electromyography in the assessment and prognosis of disorders of laryngeal mobility].

Although it was described many years ago, laryngeal electromyography is of limited use. It can easily be performed in the doctor's surgery by the intercrico-thyroid approach. The author reports on 70 examinations, 64 for mobility disorders, 6 for abnormal spasmodic movements. 15 normal plots made it possible to correct a faulty diagnosis of palsy. The prognostic contribution is not so clear-cut and must take account of the clinical circumstances and the time elapsed before examination. EMG must be performed systematically before any irreversible therapeutic decision.

Electromyography↗
PubMed1994

Single-cell fura-2 microfluorometry reveals different purinoceptor subtypes coupled to Ca2+ influx and intracellular Ca2+ release in bovine adrenal chromaffin and endothelial cells.

ATP and adenosine(5')tetraphospho(5')adenosine (Ap4A), released from adrenal chromaffin cells, are potent stimulators of endothelial cell function. Using single-cell fura-2 fluorescence recording techniques to measure free cytosolic Ca2+ concentration ([Ca2+]i), we have investigated the role of purinoceptor subtypes in the activation of cocultured chromaffin and endothelial cells. ATP evoked concentration-dependent [Ca2+]i rises (EC50 = 3.8 microM) in a subpopulation of chromaffin cells. Both ATP-sensitive and -insensitive cells were potently activated by nicotine, bradykinin and muscarine. Reducing extracellular free Ca2+ concentration to around 100 nM suppressed the [Ca2+]i transient evoked by ATP but not the [Ca2+]i response to bradykinin. ATP-sensitive chromaffin cells were also potently stimulated by 2-methylthioadenosine triphosphate (2MeSATP; EC50 = 12.5 microM) and UTP, but did not respond to either adenosine 5'-[beta-thio]diphosphate (ADP[beta S]), a P2Y receptor agonist, adenosine 5'-[alpha,beta-methylene]triphosphate (pp-[CH2]pA), a P2X agonist or AMP. Adrenal endothelial cells displayed concentration-dependent [Ca2+]i responses when stimulated with ATP (EC50 = 0.86 microM), UTP (EC50 = 1.6 microM) and 2MeSATP (EC50 = 0.38 microM). 2MeSATP behaved as a partial agonist. Ap4A and ADP[beta S] also raised the [Ca2+]i in endothelial cells, whereas AMP and pp[CH2]pA were ineffective. Lowering extracellular free Ca2+ to around 100 nM did not affect the peak ATP-evoked [Ca2+]i rise in these cells. It is concluded that different purinoceptor subtypes are heterogeneously distributed among the major cell types of the adrenal medulla. An intracellular Ca(2+)-releasing P2U-type purinoceptor is specifically localized to adrenal endothelial cells, while a subpopulation of chromaffin cells expresses a non-P2X, non-P2Y subtype exclusively coupled to Ca2+ influx.

Adenosine Triphosphate↗
PubMed1994

Histologic features of the CISH procedure.

STUDY OBJECTIVE: To evaluate the classic intrafascial SEMM (serrated-edge macromorcellated) hysterectomy (CISH) performed by pelviscopy and by laparotomy, and determine the histologic features of the procedures. DESIGN: The first 253 women who required hysterectomy were assigned to undergo the procedure by pelviscopy or laparotomy based on uterine size. PATIENTS: One hundred fifty-two women underwent CISH by pelviscopy and 101 by laparotomy. INTERVENTIONS: Between September 1991 and December 1993, the patients underwent the two procedures. Uterine leiomyomas with menstrual disorders and pressure symptoms were the principal indications (61%). MEASUREMENTS AND MAIN RESULTS: Histologic findings were in agreement with indications for the procedures. Leiomyomas and leiomyomas with adenomyosis were the most frequent findings. Histologic analysis revealed that the squamocolumnar transformation zone was totally removed in all cases, and all cervical glands were excised in 92%. CONCLUSION: Cervical dysplasia is not a contraindication to CISH, but emphasizes the importance of adequate preoperative screening. This is a conservative operation that my protect against some cervical cancers.

Adult↗
PubMed1994

Pulsatile subcutaneous versus bolus intramuscular gonadotrophin administration after pituitary suppression with a long-acting gonadotrophin-releasing hormone analogue: a controlled prospective study.

The potential advantages of pulsatile s.c. administration instead of daily bolus i.m. administration of human urinary gonadotrophin preparations were tested after the administration of a long-acting gonadotrophin-releasing hormone (GnRH) analogue within a programme for in-vitro fertilization (IVF) and embryo transfer. First, the pharmacokinetic properties of human urinary gonadotrophins were analysed with immunological and biological methods, both during bolus i.m. injections and during pulsatile s.c. administration. Second, a prospective randomized controlled study was performed in 75 patients undergoing IVF/embryo transfer in whom the effects of pulsatile s.c. administration were compared with the effects of single daily bolus i.m. injections of the same gonadotrophin preparation. The results showed that neither method of gonadotrophin administration induced measurable changes in the serum concentration of luteinizing hormone (LH). Both oestradiol and androstenedione concentrations were slightly lower during pulsatile s.c. gonadotrophin administration, suggesting that this method of gonadotrophin administration results in less LH occupying the ovarian LH receptors. Pulsatile s.c. gonadotrophin administration resembles a continuous infusion of follicle-stimulating hormone (FSH). Significant fluctuations in the serum concentrations of FSH were observed during single daily bolus i.m. administration of human urinary gonadotrophins, but the pregnancy rate of IVF/embryo transfer per cycle after pulsatile s.c. administration was not significantly better than after the daily bolus i.m. injection of gonadotrophins (42.1 versus 37.2%). It is concluded that pulsatile s.c. administration of gonadotrophins instead of single daily injections does not improve the pregnancy rate in IVF/embryo transfer.

Adult↗
PubMed1994

Dengue virus. Detection and pathogeny.

Sequences front a cDNA of dengue virus type 4 were cloned into transcription vectors. These sequences included the E, NS1, NS2A, NS2B, NS3 genes. RNA transcripts produced in vitro from these plasmids were used in hybridization assays to detect dengue viral sequences. With these RNA-probes we have been able to detect molecules of serotype-specific dengue 4 viral RNA. Moreover, the riboprobes detected viral sequences of other serotypes in the following order of sensitivity 4 > 2 > 3 > 1, and might be useful to differentiate serotypes.

Animals↗
PubMed1994

Neurocysticercosis in Brazilian children: report of 10 cases.

In a 6-year period, ten cases of neurocysticercosis were diagnosed in children with ages ranging from 4 to 13 years, in a Brazilian teaching hospital. Most of the children presented epilepsy and/or raised intracranial pressure, but meningoencephalitis and psychotic reactions were also observed. The cerebrospinal fluid (CSF) cell count ranged from 1 to 52 cells per mm3, with pleocytosis in 6 cases, mostly by lymphocytes and eosinophils. Antibodies to Cysticercus cellulosae were detected in the CSF in all cases. A cranial radiograph was abnormal in 5 out of 6 cases, and a computed tomographic (CT) scan in 4 out of 8 cases. Stool examination was positive for ova and/or proglottids of Taenia sp in 4 out of the 10 cases. Seven patients were treated with either praziquantel or albendazole plus dexamethasone; there were no important side effects, and surgical treatment was required in no case. Neurocysticercosis must be included in the differential diagnosis of seizures, raised intracranial pressure, meningitis and psychotic reactions in children living in or having travelled to the tropics. The diagnosis can be suspected by the presence of eosinophils in the CSF, and confirmed by imaging methods such as CT scans and by immunological tests in the CSF.

Adolescent↗
PubMed1993

Antiserotoninergic activity of 2-aminoethylbenzocyclanones in rat aorta: structure-activity relationships.

The antiserotoninergic activity at the serotonin receptor subtype 2 (5-HT2) of seven new 2-aminoethylbenzocyclanones was determined with respect to serotonin-induced contractions in rat aorta and compared with that of ketanserine (pA2 = 8.87). Competitive antagonism was observed in six compounds (6.72 < or = pA2 < or = 8.12). Three-dimensional structures and molecular electrostatic potential distributions of ketanserine and 2-aminoethylbenzocyclanones were analyzed. Several molecular features correlated with the rank of antiserotoninergic activity. In the case of the cyclanone fragment, the rank of activity was associated with the degree of planarity of the bicyclic system. The steric and electrostatic effects due to the loss of planarity were analyzed. In the case of the amino moiety, activity was associated with a particular spatial pattern defined by the amino nitrogen, the aromatic system, and molecular electrostatic potential minima generated by the oxygen atom.

Animals↗
PubMed1993

Predictive parameters for ovarian response to hyperstimulation with exogenous gonadotropins after suppression of gonadotropin secretion of the pituitary using a long-acting GnRH agonist.

Individually adapted gonadotropin dosage is more successful than standardized schemes for ovarian stimulation prior to in vitro fertilization and embryo transfer. Unfortunately, differences in ovarian response can not be predicted reliably. In order to develop predictive parameters for ovarian response the data from 99 cycles in 69 patients were analysed retrospectively. Before initiating ovarian stimulation for in vitro fertilization, an untreated menstrual cycle was examined using a commonly used endocrinological screening protocol. The ovaries were then stimulated with exogenous gonadotropins after previous suppression of endogenous gonadotropin secretion using a long-acting GnRH-analogue. The predictive value of this endocrinological screening protocol for ovarian response was evaluated. Ovarian response was defined as the logarithmically transformed ratio of the serum estradiol concentration at ovulation induction, divided by the number of ampoules of exogenous gonadotropins administered. Comparison of the various hormone characteristics with ovarian response led to identification of two distinct groups of patients showing reduced ovarian response: those with elevated serum levels of FSH on the third cycle day (> 9 units/l, P < 0.0001), and those with elevated serum levels of estradiol on the third cycle day (> 190 pmol/l, P < 0.02). Patients with high serum levels of TSH in the TRH test responded poorly to ovarian stimulation (P < 0.05), but also showed significantly higher serum concentrations of FSH (P < 0.01). No parameter correlated positively with ovarian response.

Adult↗
PubMed1993

Effect of P2Y agonists on adenosine transport in cultured chromaffin cells.

Adenosine transport in cultured chromaffin cells was inhibited by purinergic P2y-receptor agonists without significant changes in the affinity constant, the values being between 1 +/- 0.4 and 1.6 +/- 0.6 microM. The Vmax parameter was modified significantly, being 40 +/- 1.0, 26 +/- 5.0, 32 +/- 3.0, and 22 +/- 4.7 pmol/10(6) cells/min for control, adenosine-5'-O-(2-thiodiphosphate), 5'-adenylylimidodiphosphate, and P1,P4-di(adenosine-5'-) tetraphosphate (Ap4A) (100 microM for every effector), respectively. Ap4A, a physiological ligand for P2y receptors in chromaffin cells, showed the highest inhibitory effect (45%). This transport inhibition is explained by an increase in the cytosolic Ca2+ concentration ([Ca2+]i) and the activation of protein kinase C (PKC). Experiments of [Ca2+]i measurement with the fura-2 technique showed that P2y agonists, as well as bradykinin, were able to increase [Ca2+]i, this effect being independent of the presence of extracellular Ca2+. The peptide bradykinin, determined to be coupled to phosphatidylinositol hydrolysis and internal Ca2+ mobilization in chromaffin cells, exhibited a behavior similar to that of P2y agonists in adenosine transport inhibition (39%). P2y agonists and bradykinin increased PKC activity associated with the membrane fraction (about 50% increase in particulate PKC activity with respect to controls). The present studies suggest that adenosine transport is regulated by P2y-purinergic receptors mediated via Ca2+ mobilization and PKC activation.

Adenosine↗
PubMed1993

Comparative assessment of the leprosy antibody absorption test, Mycobacterium leprae extract enzyme-linked immunosorbent assay, and gelatin particle agglutination test for serodiagnosis of lepromatous leprosy.

A comparative assessment of three serological methods for leprosy diagnosis (the fluorescent leprosy antibody absorption [FLA-ABS] test, the Mycobacterium leprae soluble-extract enzyme-linked immunosorbent assay [ELISA], and the M. leprae particle agglutination [MLPA] test) was carried out. The objective was to identify their performance in clinical and epidemiological diagnosis of leprosy. The study group included 45 lepromatous leprosy patients under treatment. Specificity was > 95% for all three assays, and sensitivity was 95, 58, and 74% for the FLA-ABS test, the MLPA test, and the ELISA, respectively. The only cross-reactivity for M. tuberculosis-infected patients was with the soluble-extract ELISA. Although the FLA-ABS test displayed the highest specificity and sensitivity values, it can only be used in well-developed laboratories, and the patient's clinical and epidemiological background must be considered when results are interpreted because the test remains positive after therapeutic success and could be positive for some household contacts. The MLPA test is easier to perform and interpret, and it is adequate for small laboratories and epidemiological studies intended to detect active untreated or irregularly treated leprosy cases. Therefore, the FLA-ABS and MLPA tests are complementary, and both should be used for serodiagnosis of leprosy.

Agglutination Tests↗
PubMed1992

Mechanism through which GABAA receptor modulates catecholamine secretion from bovine chromaffin cells.

The actions and mechanism of GABAergic modulation of catecholamine secretion from isolated bovine chromaffin cells were investigated. The GABAA receptor agonist muscimol induced a fast rise in cytosolic [Ca2+]. The mean peak increase was 290 +/- 30 nM over basal levels. The increase in cytosolic [Ca2+] was abolished in the absence of extracellular [Ca2+] and was blocked by the GABAA antagonist bicuculline and the dihydropiridine nifedipine. Muscimol also elicited the release of catecholamines and increased the bisoxonol fluorescence indicating a cell depolarization. The [Ca2+] entry was well correlated with muscimol-evoked catecholamine secretion. When cells were treated with muscimol and a second secretagogue, a biphasic behavior was revealed. Muscimol enhanced the catecholamine release evoked by low concentrations of nicotine or K+, whereas release obtained at high concentrations of nicotine or K+ was actually inhibited. When the muscimol effect on membrane potential was studied in the presence of low K+ or nicotine concentrations, an enhancement of the bisoxonol fluorescence was observed. This effect was reversed at high concentrations of both K+ and nicotine. Measurement of 36Cl- fluxes showed an increase in membrane permeability to Cl- during muscimol stimulation. The influx or efflux in Cl- was dependent on membrane potential. In normal conditions, with a K+ concentration of 5.4 mM, a Cl- efflux was observed by both radiometric techniques, with 36Cl- and by the use of the chloride-sensitive fluorescent probe 6-methoxy-N-(3-sulphopropil)quinolinium, as indicator of intracellular Cl-. At high nicotine (20 mM) or K+ concentrations (105 mM) a Cl- influx was observed using 6-methoxy-N-(3-sulphopropil)quinolinium.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Human tuberculosis due to Mycobacterium bovis: report of 10 cases.

During the period 1986-1990, 10 cases of human disease caused by Mycobacterium bovis were diagnosed in our hospital. The incidence, in relation to the cases of disease from Mycobacterium tuberculosis diagnosed in the same period, was 0.9%. The patients had an average age of 32 years (range 5-68 years). Pulmonary disease was observed in 5 patients (50%), lymphadenitis in 2, pleural effusion in 2 and peritoneal in 1. The most significant of the epidemiological features was that 2 patients were veterinary students. There was 1 death from ovarian neoplasia with abdominal dissemination. The other cases responded favourably to treatment with standard chemotherapy of 6-12 months achieving cure, without relapse, of all the patients.

Adolescent↗
PubMed1992

Ca(2+)-stores mobilization by diadenosine tetraphosphate, Ap4A, through a putative P2Y purinoceptor in adrenal chromaffin cells.

1. Diadenosine tetraphosphate (Ap4A) evoked a concentration-dependent increase in cytosolic [Ca2+] in resting chromaffin cells. The EC50 value for this action was 28.2 +/- 6.6 microM. This effect was also produced by diadenosine pentaphosphate (Ap5A) with an EC50 of 50 +/- 7 microM. 2. In contrast with this effect, pretreatment with Ap4A or Ap5A induced a 30% reduction in Ca2+ entry following 10 microM dimethylphenylpiperazinium. 3. The elevation in cytosolic [Ca2+] induced by Ap4A was persistent in approximately 100 nM external [Ca2+] and was sensitive to depletion of internal Ca2+ stores by a bradykinin prepulse or whole cell depletion in Ca2+. 4. The effect of Ap4A was mimicked and desensitized by the agonist adenosine 5'-O-(2-thiodiphosphate), and blocked by the P2Y-receptor antagonist, cibachrome blue. The P2X-receptor agonist alpha,beta-methylene adenosine 5'-triphosphate was inactive both by itself or in combination with Ap4A. This is compatible with a P2Y-purinoceptor-mediated action.

Adrenal Glands↗
PubMed1991

Glutamate exocytosis evoked by 4-aminopyridine is inhibited by free fatty acids released from rat cerebrocortical synaptosomes.

The Ca(2+)-dependent release of glutamate induced by 4-aminopyridine (4-AP) in rat cerebral cortical synaptosomes was reduced by removal of bovine serum albumin (BSA) from the incubation medium. The decrease in the glutamate release in the absence of BSA was consistent with a reduction in the rise in cytosolic free [Ca2+] after depolarization with 4-AP. Contrarily, neither the glutamate release nor the elevation in cytosolic free [Ca2+] after depolarization with 30 mM KCl was altered by the removal of BSA. The inhibitory action of the free fatty acids released during the incubation of synaptosomes was also observed when exogenous free fatty acids were added to the medium in the presence of BSA. The highest inhibition of 4-AP-induced release of glutamate was observed in the presence of arachidonic acid. The results strongly suggest an inhibitory action of free fatty acids by decreasing Ca2+ entry and glutamate release in rat cerebrocortical synaptosomes.

4-Aminopyridine↗