Biomedical subjects

T Castillo

Publications and source records attributed to T Castillo.

At least 19 recordsLinked to original sources

PubMed2004

Bolus application of remifentanil with propofol for dilatation and curettage.

BACKGROUND AND OBJECTIVE: This study was designed to determine which single bolus dose of remifentanil in combination with propofol and nitrous oxide is best to control the haemodynamic, autonomous and somatic responses in patients scheduled for dilatation and curettage of the uterine cervix. We evaluated the adequacy of different bolus doses of remifentanil, associated with propofol and nitrous oxide, for dilatation and curettage in a prospective double-blind study. METHODS: After institutional approval and informed consent, 34 healthy females undergoing curettage to remove material from the uterus after spontaneous abortion were randomized to receive remifentanil 0.5 microg kg(-1) intravenously (i.v.) (Group A; n = 4), 1 microg kg(-1) i.v. (Group B; n = 15) or 1.5 microg kg(-1) i.v. (Group C; n = 15), with propofol 2 mg kg (-1) i.v. in all groups. Anaesthesia was maintained with 60% nitrous oxide in oxygen. Haemodynamic, somatic and autonomic signs of light anaesthesia were registered to assess the response to surgical stress. Recovery times and Aldrete score were recorded at the end of the procedure. RESULTS: The groups were similar with regard to biometric data and duration of surgery. The poor results using the lowest dose of remifentanil obliged us to abandon this dose. The total dose of remifentanil was larger in Group C (100 +/- 5.7 microg vs. 65 +/- 4.1 microg in Group B; P < 0.05), but more patients required extra bolus injections in Group B (69% vs. 38% in Group C; P < 0.01). Recovery times were significantly shorter in Group C. Aldrete scores when leaving the operation room was similar. CONCLUSIONS: Remifentanil 1.5 microg kg(-1) i.v. with propofol 2 mg kg(-1) i.v. and 60% nitrous oxide in oxygen provided the best anaesthetic control with the fastest recovery times.

Adult↗

PubMed2000

Intravenous infusion of 4-AP in chronic spinal cord injured subjects.

STUDY DESIGN: A prospective double blind cross over trial of intravenous 4-Aminopyridine (4-AP). OBJECTIVE: To determine the efficacy of this drug in the treatment of spinal cord injured (SCI) patients for neurologic impairment, pain and spasticity. SETTING: The post anesthesia care unit (PACU) of a tertiary care acute hospital. METHODS: Twelve paraplegic patients were enrolled in a double blind cross over intravenous trial of 4-Aminopyridine (4-AP). Thirty milligrams of 4-AP or placebo were administered over a 2 h period. Patients were serially examined during and after the infusion clinically for pain, sensorimotor function, hypertonicity and motor control using electromyography (EMG). Samples of blood and cerebrospinal fluid (CSF) were also analyzed at similar intervals. RESULTS: Despite penetration of 4-AP into the CSF, no significant differences were noted in the clinical and EMG parameters at the times measured. Individual changes in sensory function were reported by some patients in both the placebo and 4-AP trials, however mean values were not robust. Frequently, patients complained of unpleasant symptoms during the 4-AP infusion. CONCLUSION: The intravenous route may not be the best way to administer this drug as no short term benefits were observed.

4-Aminopyridine↗

PubMed1999

[Relationship between leptin and insulin sensitivity in patients with polycystic ovary syndrome].

BACKGROUND: The relationship between leptin and insulin sensitivity, sexual steroids and insulin concentrations in women with polycystic ovary syndrome is still controversial. The objective of this study was to assess the relationship between insulin levels, insulin resistance parameters and serum leptin concentrations in healthy and polycystic ovary syndrome women. PATIENTS AND METHODS: 33 hyperandrogenic polycystic ovary syndrome women (GHA) and 27 healthy women (GS) were included in this study. Leptin, insulin, sex-hormone binding globulin (SHBG), testosterone and estradiol concentrations were determined in a basal sample. Body mass index, waist diameter and waist to hip ratio were recorded. Insulin sensitivity was calculated by means of insulin tolerance test and glycemia/insulinemia ratio. RESULTS: The leptin concentration was not different between GHA and GS. Insulin levels and free testosterona index (FTI) were higher in GHA than GS (p < 0.01). The glycemia/insulinemia ratio, SHBG levels, and insulin sensitivity were lower in GHA (p < 0.01). In both groups positive correlations between leptin concentration and body mass index (p < 0.01), waist diameter (p < 0.01), insulin levels (p < 0.01) and glycemia/insulinemia ratio (p < 0.01) were observed. Only GHA showed correlation between insulin sensitivity and leptin concentration (p < 0.02). SHBG and leptin levels were not correlated. CONCLUSIONS: The leptin concentration was not different between GHA and healthy women, although they are metabolically different. This phenomenon could be due to the fact that in hyperandrogenic women the effects of insulin resistance and hyperandrogenemia counteract each other.

Adolescent↗

PubMed1998

Naltrexone effects on insulin sensitivity and insulin secretion in hyperandrogenic women.

A total of 12 women (24.2 +/- 1.6 years old, BMI 36.7 +/- 1.5 Kg/m2) with hyperandrogenism (HA) and with normal glucose tolerance test were studied to evaluate the involvement of endogenous opioids in the pathophysiology of insulin secretion and insulin sensitivity in HA by administering naltrexone, an oral opioid receptor antagonist. Six patients received naltrexone orally (75 mg daily) and another six received placebo for 12 weeks (double-blind study). Before and after therapy a frequently sampled intravenous glucose tolerance test (FSIVGTT) was performed. The insulin sensitivity index (SI) was determined by Bergman's program. SHBG, DHEAS, testosterone, free androgen index (FAI) and plasma concentrations of IGF-I and IGFBP-1 were determined in 3 basal samples, before and after therapy. Treatment with naltrexone in hyperandrogenic patients resulted in a decrease in fasting insulin concentrations of 40% and C-peptide concentrations of 50% (p < 0.05). Insulin and C-peptide from the FSIVGTT displayed a similar pattern with a fall in the area under the curve under naltrexone treatment of 34% for insulin and 35% for C-peptide. Insulin sensitivity did not change under naltrexone (1.26 +/- 0.19 vs 1.32 +/- 0.32 10(-4) x min(-1)/(uU/ml)) or placebo (0.95 +/- 0.19 vs 1.12 +/- 0.28 10(-4) x min(-1)/(uU/ml)) administration. However, glucose effectiveness increased significantly with naltrexone (2.231 +/- 0.002 vs 3.354 +/- 0.006 x 10(-2) min(-1)). Glucose (fasting and area under the curve) was not modified significantly after naltrexone administration. Baseline hormone levels were similar in the two groups, and they did not change after long-term treatment with naltrexone or placebo. In conclusion, these results support the hypothesis of elevated opioid tonus and increased insulin secretion as a possible mechanism of hyperinsulinism in a group of hyperandrogenic women of ovarian origin. This alteration could act as an additional factor in the pathogenesis of insulin resistance found in an important proportion of these patients.

Adolescent↗

PubMed1998

[Polycystic ovary syndrome: relationship of insulin tissular sensitivity, LH secretion and ovarian morphophysiologic changes].

BACKGROUND: Insulin resistance to LH hypersecretion are recognized features of polycystic ovary syndrome. Previous studies have suggested that both defects are independent from each other. AIM: To examine the relationship between insulin sensitivity and LH secretion in women with polycystic ovary syndrome. PATIENTS AND METHODS: Eighteen women with clinical and biochemical evidence of hyperandrogenism, normal oral glucose tolerance test and polycystic ovaries on ultrasonography, were studied. Insulin sensitivity was assessed using the insulin tolerance test. LH secretion was studied integrating LH values of blood samples taken every 10 minutes for 6 h. Testosterone, testosterone index, SHBG and IGFBP-1 were measured in three selected samples and ovarian volume was assessed by ultrasound. RESULTS: Insulin sensitivity ranged from 0.06 to 0.75 and the area under the curve for LH, from 532 to 8.517 IU/L/6 h. No correlation was found between these two parameters and between each parameter and ovarian volume or androgen concentration. Positive correlations were observed between insulin sensitivity and SHBG concentrations (r = 0.612 p < 0.01) and IGFBP-1 concentrations (r = 0.588 p < 0.001). When compared to patients body mass index of less than 30 kg/m2, patients with body mass index over 30 kg/m2 had significantly lower insulin sensitivity and higher LH levels. In the latter a positive correlation between insulin sensitivity and the area under the curve for LH was observed (r = 0.683 p < 0.02). CONCLUSIONS: Obese polycystic ovary syndrome patients exhibited an inverse correlation between insulin resistance and LH hypersecretion, suggesting a relationship between both defects.

Adult↗

PubMed1997

[Biochemical markers and methods to assess insulin resistance in normal, obese and hyperandrogenic women].

BACKGROUND: Euglycemic or hyperglycemic clamp and the frequently sampled i.v. glucose tolerance test are the most frequently used methods to assess insulin resistance. However, both are expensive and cumbersome. AIM: To evaluate the relative or discriminatory usefulness of sex hormone binding globulin (SHBG), dehydroepiandrosterone sulphate (DHEAS) and insulin like growth factor binding protein 1 (IGFBP-1) as markers of insulin resistance and to estimate the tissue sensitivity to insulin by means of the insulin tolerance test (ITT) and the frequently sampled i.v. glucose tolerance test (IVGTT) in normal, obese and hyperandrogenic women. SUBJECTS AND METHODS: Six normal, 6 obese and 12 hyperandrogenic women of similar ages, were studied. In two consecutive days, the ITT and the IVGTT were performed and a basal blood sample was obtained to measure SHBG, DHEAS and IGFBP-1. Insulin sensitivity was calculated as the blood glucose slope in the ITT and with the minimal model of Bergman in the IVGTT. RESULTS: Insulin sensitivity, measured with ITT was 0.58 (0.53-0.63) in normal, 0.38 (0.05-0.59) in obese and 0.20 (0.0-0.36) in hyperandrogenic women. The figures for the IVGTT were 7.97 (4.1-15.4), 2.41 (0.81-4.89) and 1.1 (0.46-1.88), respectively. Both methods had a positive correlation coefficient of 0.792 (p < 0.001). SHBG was 87.0 m 37.9 and 18.3 nmol/l in normal, obese and hyperandrogenic women, respectively (p < 0.09). IGFBP-1 values were 3.0, 2.1 and 1.6 ng/ml respectively (p < 0.05). DHEAS values were 132, 190 and 206 ug/dl, respectively (ND). CONCLUSIONS: ITT is a simple and reliable method to assess insulin sensitivity. SHBG discriminates subjects with different levels of insulin sensitivity. Since it is easy to measure, it could be used as a marker on insulin sensitivity.

Adult↗

PubMed1997

[Effects of metformin on insulin resistance in obese and hyperandrogenic women].

BACKGROUND: Metformin is a biguanide often used in obese diabetics that improves tissue sensitivity to insulin. AIM: To assess the effects of metformin on tissue insulin sensitivity in obese and hyperandrogenic women. PATIENTS AND METHODS: Eight obese and eight obese and hyperandrogenic women received metformin 850 mg orally during 12 weeks. Before and at the end of the treatment period, an insulin tolerance test to measure insulin sensitivity was performed and blood was drawn to measure sex hormone binding globulin (SHBG), dehydroepiandrosterone sulphate (DHEAS), testosterone, triglycerides, total and HDL cholesterol. The free androgen index was calculated for each sample. RESULTS: After metformin treatment, the insulin sensitivity index improved from 0.38 (0.05-0.5) to 0.43 (0.25-0.59) in obese women and from 0.2 (0-0.36) to 0.3 (0.06-0.4) in obese and hyperandrogenic women. SHBG increased and total cholesterol and triglycerides decreased significantly in both groups. No other significant changes were observed. CONCLUSIONS: Metformin has a favorable effect on tissue sensitivity to insulin, SHBG and serum lipids in obese and hyperandrogenic women.

Adult↗

PubMed1996

[Insulin tolerance test. A useful test to determine insulin resistance in obese hyperandrogenic women].

BACKGROUND: Insulin tolerance test is a simple method to measure insulin resistance that has a good correlation with glucose clamp studies. AIM: To use the insulin tolerance test to detect differences in insulin sensitivity between healthy and obese hyperandrogenic women and to correlate its results with those of the minimal model intravenous glucose tolerance test. PATIENTS AND METHODS: Five healthy women aged 27 +/- 7 years old with a body mass index of 21 +/- 2 kg/m2 and six hyperandrogenic women aged 25 +/- 4 years old with a body mass index of 40 +/- 5 kg/m2 were studied after a 10 hours fast. For the insulin tolerance test 0.1 U/kg of crystalline insulin were injected intravenously and blood samples were drawn to measure glucose at -5,0,3,5,10 and 15 min. after the injection. Insulin resistance was calculated using the slope of descending blood glucose levels (SI1). For the intravenous glucose tolerance test, 29 blood glucose samples were obtained after an intravenous injection of 0.3 g glucose/kg followed by an injection of 0.02 U/kg of crystalline insulin. Insulin sensitivity (SI2) was calculated using Bergman's minimal model. RESULTS: Healthy women had a SI1 of 0.58 (range 0.53-0.63) and a SI2 of 7.9 x 10(-4) x min-1/microU/ml (range 4.15-9.11). For hyperandrogenic women were 0.18 (range 0.06-0.29) and 0.9 x 10(-4) x min-1/microU/ml (range 0.46-1.79), respectively. Both methods had a positive correlation coefficient of 0.859 (p < 0.001). CONCLUSIONS: Insulin tolerance test is a good method to measure insulin resistance and has a good correlation with the frequently sampled intravenous glucose tolerance test.

Adult↗

PubMed1995

Functional luteolysis in response to hydrogen peroxide in human luteal cells.

To evaluate the effect of reactive oxygen species in human corpus luteum function, we investigated whether hydrogen peroxide (H2O2) affects the in vitro luteal cell production of steroids. H2O2 treatment (1.0-100 microM) of mid and late luteal cell cultures elicited a dose-dependent decrease in basal progesterone production. However, treatment of mid luteal cells with a low concentration of H2O2 (0.01 microM) significantly stimulated progesterone secretion (P < 0.05). In addition, H2O2 (100 microM) markedly inhibited human chorionic gonadotropin (hCG)-stimulated progesterone and estradiol secretion. cAMP production was enhanced (2.4-fold, P < 0.05) by hCG treatment of luteal cells. The addition of H2O2 (0.1-100 microM) to hCG-stimulated luteal cell cultures elicited a decrease in cAMP concentration (P < 0.05) and in the specific binding of radiolabeled hCG by luteal cells. Progesterone and estradiol production stimulated by dibutyryl cAMP were significantly inhibited by H2O2 (P < 0.05). These findings suggest that H2O2 interferes with basal steroid production and, in hCG-stimulated conditions, it may inactivate the gonadotropin-receptor complex. The anti-steroidogenic action of H2O2 therefore raises the possibility of a modulatory role of H2O2 in human luteal steroidogenesis.

Adult↗

PubMed1994

Steroidogenic capacity and oxidative stress-related parameters in human luteal cell regression.

The steroidogenic capacity and oxidative stress-related parameters of the human corpus luteum (CL) at different stages of the luteal phase were studied under basal and human chorionic gonadotropin (hCG)-stimulated conditions. Mid CL exhibited the maximal steroidogenic capacity, together with lower levels of glutathione and higher thiobarbituric acid reactants content, macrophage count, and superoxide dismutase (SOD) activity, compared to the late CL. Addition of hCG to luteal cell cultures led to a preferential increase in progesterone synthesis in the late CL compared to the mid CL, without changes in the oxidative stress-related parameters, except for the increased SOD activity found in the late CL. It is concluded that an oxidative stress condition is established in the mid CL, coinciding with the maximal steroidogenic capacity and macrophage infiltration of the organ, which may be of relevance as one of the major mechanisms initiating CL involution in the human.

Adult↗

PubMed1994

[Effect of chronic blockade of the opiodergic receptor on insulin resistance in a hyperandrogenic woman].

We report a woman with insulin resistance associated with hyperandrogenism and acanthosis nigricans (HAIR-AN syndrome) treated during 30 days with the prolonged action opioid antagonist Naltrexone. During its administration, decreases in basal blood glucose and serum insulin, insulin and glucose response to a glucose load and plasma testosterone were observed. These findings suggest that opioid activity could play a critical role in the physiopathology of hyperinsulinemia in hyperandrogenic women.

Acanthosis Nigricans↗

PubMed1992

Role of cytochrome P-450 2E1 in ethanol-, carbon tetrachloride- and iron-dependent microsomal lipid peroxidation.

This study investigated the role of cytochrome P-450 2E1 in enhanced microsomal lipid peroxidation in experimental alcoholic liver disease. We also examined the contribution of this isoform to the increased microsomal injury in alcoholic liver disease caused by carbon tetrachloride-induced or iron-induced oxidant stress. Adult male Wistar rats were intragastrically infused with a high-fat diet and ethanol or glucose for 16 wk; this resulted in hepatic lipid peroxidation and fibrogenesis in the ethanol-fed animals. Microsomes were isolated by differential centrifugation in the presence of 100 mumol/L deferoxamine, washed twice in buffer without deferoxamine and incubated in the absence or presence of ethanol (50 mmol/L), carbon tetrachloride (150 mumol/L), ferric citrate (50 mumol/L) or ferric citrate plus ethanol at 37 degrees C for 30 min in an NADPH-generating system. The basal rate of lipid peroxidation in microsomes isolated from ethanol-fed rats was increased by 52% compared with that in microsomes from controls. Carbon tetrachloride-induced and ferric citrate-induced lipid peroxidation were also accentuated in microsomes from ethanol-fed rats, by 76% and 108%, respectively. Ethanol added in vitro significantly reduced basal (-58%) and ferric citrate-induced (-48%) lipid peroxidation in microsomes from ethanol-fed rats, whereas it had an insignificant effect on that in control microsomes. In fact, this protective effect of ethanol on microsomes from ethanol-fed rats resulted in attenuation of the difference in the level of microsomal lipid peroxidation between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1992

[Fiber endoscopy in the extraction of foreign bodies from the gastrointestinal tract].

23 patients that they swallowed foreign bodies, were treated. There were 16 male and 7 female, between 3 and 85 years old; 6 children and 17 adults. Of all, 7 were psychiatric patients. 15 foreign bodies were removed by upper digestive fiberendoscopy and 2, by procto/colonoscopy, without early nor late complications. 8 foreign bodies were eliminated spontaneously through the rectum/anus. Fiberendoscopy is an excellent method for treatment in these clinical problems.

Adolescent↗

PubMed1991

Nonpropulsive esophageal contractions and gastroesophageal reflux.

Nonpropulsive esophageal contractions radiologically described as tertiary contractions or "corkscrew" esophagus suggest the presence of an underlying motility disorder and may lead to impaired acid clearance. The goals of this study were to determine the prevalence and role of gastroesophageal reflux (GER) in patients with tertiary contractions. Thirty-five consecutive patients with spontaneous, repetitive, nonpropulsive esophageal contractions noted on esophagography were studied with endoscopy, infusion esophageal manometry, and 24-h ambulatory pH monitoring. All patients had esophageal symptoms, mainly dysphagia, heartburn, and chest pain, but only three were found to have esophagitis by endoscopy and biopsy. Nineteen patients had repetitive, nonlumen-obliterating, nonperistaltic (tertiary) contractions, six had corkscrew esophagus, and 10 had forceful, lumen-obliterating simultaneous contractions (rosary bead esophagus). Twenty patients (58%) had GER by pH criteria with mean values: % time pH less than 4, 40.9; %upright pH less than 4, 41; %supine pH less than 4, 44.3%; number of episodes with greater than 5 min of pH less than 4, 12. Esophageal motility revealed "nutcracker" esophagus in eight, low LESP in two, and nonspecific esophageal motility disorder in 10. Symptoms or severity of nonperistaltic contractions did not correlate with GER. Radiologically demonstrable free reflux or the presence of heartburn did not predict GER. We conclude that 1) GER occurs in up to 58% of patients with nonpropulsive (tertiary) esophageal contractions on esophagography, and may play a role in the induction of abnormal peristaltic activity of the esophageal body; 2) GER is usually not associated with endoscopic evidence of esophagitis or characteristic symptoms, and is recognized by 24-h pH monitoring. We speculate that detection and treatment of GER may improve the symptomatic management of patients with nonpropulsive esophageal contractions.

Adult↗

PubMed1990

[Chronic diarrhea: clinical aspects].

A retrospective study on the syndrome of chronic diarrhea was carried out on 50 revised clinical histories. The patients were hospitalized at the E. Rebaglati M. Hospital between April 1983 and March 1988. The purpose of the study was to evaluate the signs and symptoms of the syndrome, as well as the etiological agents and the methodology used for diagnoses. The selection criteria involved patients diagnosed as suffering from "chronic diarrhea of undetermined causes" upon entry. Seven were excluded due to incomplete study whereas 2 were diagnosed as acute infections diarrhea. Forty one patients were definite cases of chronic diarrhea and they were divided between 2 groups: the first one or Chronic Organic Diarrhea (58.53%) and the second one or Chronic Functional Diarrhea (41.46%). Out of the 41 revised clinical histories with chronic diarrhea, the following were the foundings: (1) the syndrome affects the economically active populations mainly and the length of the disease was more than 3 weeks in all the patients; (2) anemia, fever, weight loss, nightime bowel movements and bloody stools suggest organic problems whereas psychiatric disorders, daytime bowel movements, abdominal pain, disease recurrence and absence of detectable organic pathology suggest functional problems; (3) the most common cause of chronic diarrhea is the Irritable Bowel Syndrome followed by infectious diseases, with parasitosis in the first place; and (4) bearing in mind the mainly colonic affection and the predominant infectious diseases, the methodology used for their diagnosis would bring out good results.

Adult↗

PubMed1989

[Chronic gastritis and intestinal metaplasia].

Much has been written about gastric mucosae behavior and the occurrence of intestinal metaplasia. The aim of this paper is to learn something more about these matters in peruvian population. We selected 100 patients with endoscopically no localized lesions between 30 to 70 years of age. We took 8 samples of gastric mucosae in each patient which were carefully examined for the presence of inflammatory changes, settle the line type between antral and fundic mucosae and the frequency of intestinal metaplasia finding. The results showed disagreement between endoscopic and histological findings, so we conclude it is better to diagnose chronic gastritis on the basis of histological parameters. The line between antral and fundic mucosae was of the close type one found in 87% of all cases and it advanced proximally with increasing age. Intestinal metaplasia was present in 46% of the whole number of patients and the rate of occurrence increased in 50% over 50 years age. These findings will let us compare future investigations of gastric mucosae behavior with localized benign or malign lesions.

Adult↗

PubMed1988

Serum proline and blood lactate levels in alcoholic patients without hepatic failure: relationship with alcohol ingestion and histological activity.

It has not yet been established whether serum proline and blood lactate levels are increased in alcoholic liver disease. We measured serum proline and blood lactate in controls and in patients with different stages of alcoholic liver disease in the absence of hepatic failure. Samplings were done in both abstinent and drinking alcoholics. Compared to controls, there was a striking increase in serum proline levels in 52 abstinent alcoholics with little or no hepatic fibrosis by histological assessment (0.10 +/- 0.01 vs. 0.155 +/- 0.008; p less than 0.005). Blood lactate levels were within the normal range and did not correlate with serum proline levels. On the other hand, serum proline and blood lactate levels were independent of hepatic necrosis and inflammation scores. In addition, in 10 patients with blood alcohol concentrations between 0.3 mg/ml and 7.8 mg/ml, serum lactate and proline were significantly elevated (2.42 +/- 0.29 mg/ml and 0.275 +/- 0.0026 mg/ml, respectively; p less than 0.005). These results show that there is an association between serum proline levels and the abstinence period in alcoholic patients. They further suggest that in alcoholic patients neither serum proline nor blood lactate concentrations are reliable markers for liver histological activity (necrosis and inflammation) or fibrosis.

Adult↗

PubMed1983

Limitation of pulsatility index as a diagnostic tool in the newborn.

Pulsatile flow in the anterior cerebral arteries was studied and pulsatility index (PI) calculated by 3 observers in 10 newborn infants in order to establish the reproducibility of a noninvasive Doppler technique. No significant differences were noted among the observers and the estimated error of observation was 0.073. Subsequently, 14 healthy preterm infants were studied daily by a single observer in an attempt to establish a normal range of PI for prematures in the first 5 days of life. The babies were concomitantly studied with serial ultrasound examinations to rule out intracranial hemorrhage. The study revealed good interobserver reliability but wide variation of PI in normal, healthy premature infants with values falling within abnormal ranges previously described in asphyxiated infants or those with intraventricular hemorrhage (IVH). Caution is advised in using the PI to predict outcome.

Cerebral Arteries↗