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L M Torres

Publications and source records attributed to L M Torres.

At least 37 records · Page 2Linked to original sources
PubMed2000

Spontaneous apparent clinical resolution with histologic persistence of a case of extramammary Paget's disease: response to topical 5-fluorouracil.

An 86-year-old woman presented with a 3-year history of an erythematous axillary lesion, which was histologically confirmed to be extramammary Paget's disease (EMPD) confined to the epidermis and adnexa. Surprisingly, spontaneous clinical regression occurred in the lesion, but Paget's cells persisted within the epidermis and adnexa on histologic examination. One year of intermittent topical chemotherapy with 5-fluorouracil resulted in ulcers that were interpreted as EMPD and completely excised. Histologic examination showed a complete absence of Paget's cells. To our knowledge, only one previous report investigated apparent spontaneous clinical resolution with histologic persistence of EMPD. We emphasize that topical 5-fluorouracil cannot be considered a safe treatment modality for EMPD, but it may be useful in certain cases in which the extent of the lesions, or the general condition of the patient, advise against surgery or radiotherapy.

Administration, Topical↗
PubMed1999

[Remifentanyl. Indications in anesthesia].

Remifentanil is a new opioid in the fentanyl family. Developed and marketed by Glaxo Wellcome Inc., it was approved by the U.S. Food and Drug Administration in July 1996 and has been available for use in Spain since the end of 1997. Remifentanil is an analog of fentanyl (4-piperidyl anilide) with a methyl-ester group that allows the molecule to be hydrolyzed by esterases in plasma and tissues. Rapid onset and metabolism make it an easy drug to control for achieving the desired depth of anesthesia, although these aspects are also the drug's main drawbacks given that the anesthesiologist must plan and initiate postoperative analgesia before surgery ends. Rapid onset and potency also mean that the use of this drug for either postoperative analgesia or monitored sedation in awake state with spontaneous breathing needs further study to assess safety.

Analgesics, Opioid↗
PubMed1998

In vitro and in vivo study of the clastogenicity of the flavone cirsitakaoside extracted from Scoparia dulcis L. (Scrophulariaceae).

The mutagenic effect of the flavone cirsitakaoside extracted from the medicinal herb Scoparia dulcis was evaluated in vitro by using human peripheral blood cultures treated with doses of 5, 10, and 15 microg of the flavone/ml culture medium for 48 h. The compound proved to be mutagenic at the highest concentration tested (15 microg/ml). Furthermore, the proliferative index was significantly reduced in all cultures treated with the flavone, although the mitotic index was not reduced. However, the clastogenic activity of the flavone cirsitakaoside was not observed when Swiss mice were treated orally with doses of 10, 20, and 30 mg/animal for 24 h.

Adult↗
PubMed1998

[Comparative study of sevoflurane and nitrous oxide versus halothane and nitrous oxide in pediatric anesthesia: efficacy and hemodynamic characteristics during induction].

OBJECTIVES: To study the efficacy, side effects and hemodynamics of anesthetic induction in pediatric patients using sevoflurane and nitrous oxide or halothane and nitrous oxide. PATIENTS AND METHODS: We studied 80 pediatric ASA I-II patients aged between 1 and 10 years old scheduled for infraumbilical surgery of short duration. The patients were randomly assigned to two groups of 40 to receive one of the two drug combinations. All the children were premedicated with nasal midazolam 0.2 mg.kg-1. Induction was by inhalation of increasing concentrations of sevoflurane or halothane. The maximum inspired concentration during induction was 7% for sevoflurane and 3% for halothane. We analyzed induction time, side effects and hemodynamic variables. RESULTS: The induction time was 2.06 +/- 0.5 min for halothane and 1.6 +/- 0.6 min for sevoflurane (p < 0.01). We observed no differences between the groups in coughing, laryngospasm, bronchospasm, secretions, apnea, nausea, vomiting, agitation or hiccoughing. Supraventricular beats appeared in 22.5% of patients in the halothane group and in 5% of the sevoflurane group. Induction with both anesthetics caused significant decreases from baseline blood pressure levels but no significant changes in heart rate. CONCLUSIONS: Inhaled sevoflurane in 60% nitrous oxide provides rapid but gentle anesthetic induction, with hemodynamic stability and a low incidence of airway complications. Sevoflurane is therefore a reasonable alternative to halothane for pediatric surgery.

Anesthesia, Inhalation↗
PubMed1998

Microsatellite instability in cervical intraepithelial neoplasia.

We studied the incidence of microsatellite instability (MI) in lesions defined as cervical intraepithelial neoplasia (CIN). The human papillomavirus (HPV) status of the tissues was also determined. DNA from tissue samples and autologous lymphocytes were studied for five loci located within or adjacent to the DNA mismatch repair genes. Replicate errors were detected in 7 out of 47 (14.8%) samples of cervical tissue from 24 women. Our results indicate that the defect in DNA repair-associated genes does not appear to be necessary for the selection of clones which progress from dysplasia to carcinoma. Although HPV DNA of highly oncogenic types (16/18) was detected in most cervical lesions and may be an important factor for MI, we also detected MI in two loci in HPV-negative normal tissue, indicating that further events can also be involved in mismatch repair defects.

Adult↗
PubMed1996

Sympathomimetic effects of Scoparia dulcis L. and catecholamines isolated from plant extracts.

The herb Scoparia dulcis L. is used in Brazilian folk medicine to treat bronchitis, gastric disorders, haemorrhoids, insect bites and skin wounds, and in oriental medicine to treat hypertension. A previous study has shown that extracts of S. dulcis have analgesic and anti-inflammatory properties; in this work the sympathomimetic activity of an ethanolic extract of Scoparia dulcis L. has been investigated in rodent preparations in-vivo and in-vitro. Administration of the extract (0.5-2 mg kg-1, i.v.) to anaesthetized rats produced dose-related hypertension blocked by the alpha-adrenoceptor antagonist prazosin (1 mg kg-1). Partition of the extract in chloroform-water yielded an aqueous phase 20 times more potent than the extract; this produced hypertension in either reserpine-treated or pithed rats. In untreated and reserpine-treated rats the same fraction (1-3 x 10(3) micrograms mL-1) produced concentration-dependent contractions of the vas deferens musculature parallel to those obtained with noradrenaline (10(-8)-10(-4)M). Prazosin (10(-7)M) reduced the maximum contractile effect of the aqueous fraction, and shifted the concentration-response curves for noradrenaline to the right. The aqueous fraction (25 and 50 micrograms mL-1) increased the inotropism of electrically driven left atria of rats, the effect being blocked by propranolol (0.4 microgram mL-1). In preparations of guinea-pig tracheal rings the aqueous fraction (1-3 x 10(3) micrograms mL-1) relaxed the muscle contraction induced by histamine (10(-4) M) in proportion to the concentration. The effect was antagonized competitively by propranolol (1.5 microM). High-performance liquid-chromatographic analysis of the aqueous fraction revealed the presence of both noradrenaline and adrenaline in the plant extract. The results indicated that both catecholamines may account for the hypertensive and inotropic effects obtained after parenteral administration of S. dulcis extracts. This sympathomimetic activity is, however, unrelated to the previously reported analgesic and anti-inflammatory properties of the plant extract, but may explain its effectiveness upon topical application in the healing of mucosal and skin wounds.

Analgesics↗
PubMed1996

[Comparative study of recovery from general anesthesia with halothane or sevoflurane in pediatrics].

OBJECTIVES: To assess the clinical signs of awakening and recovery from anesthesia with sevoflurane and 60% nitrous oxide in comparison with halothane and nitrous oxide administered to children. PATIENTS AND METHOD: A prospective study in 39 pediatric ASA I-II patients under 10 years of age scheduled for infraumbilical or otolaryngological surgery. The patients were randomly assigned to 2 groups to receive sevoflurane (n = 20) or halothane (n = 19). All the children received nasal doses of 0.2 mg/kg-1 midazolam before surgery. Induction was achieved by inhalation of a mixture of 40% oxygen and 60% nitrous oxide by face mask along with increasing concentrations of sevoflurane or halothane. Maintenance was with halogenated anesthetic at 1 MAC and 60% nitrous oxide-oxygen along with nerve blockade in the infraumbilical procedures or intravenous analgesia in the otolaryngological operations. We recorded time until awakening, orientation, score on the Aldrete scale and adverse effects during the recovery period. RESULTS: The children who received sevoflurane awoke and were well oriented earlier than were those in the halothane group (10.7 +/- 5.8 versus 18.7 +/- 9.8 min until awakening and 15.4 +/- 8.6 versus 22.1 +/- 10 min for orientation); likewise the sevoflurane group children received higher scores on Aldrete's scale earlier than did those in the halothane group. There were no statistical differences between the 2 groups with respect to side effects during the period of awakening and recovery. CONCLUSIONS: Awakening and recovery are significantly faster with sevoflurane than with halothane, while the incidence of side effects are similar with the 2 agents.

Anesthesia Recovery Period↗
PubMed1993

HLA class I expression and HPV-16 sequences in premalignant and malignant lesions of the cervix.

A series of 10 normal cervix epithelia, 38 condylomas, 17 CIN (cervical intraepithelial neoplasm) I/II (low-grade CIN), 10 CIN III (high-grade CIN), 27 squamous cell carcinomas and 7 adenocarcinomas of the cervix were studied in paraffin-embedded sections for the expression of MHC class I antigens, using antibodies against HLA antigens and the immunoperoxidase technique. A PCR technique was also used to evaluate the presence of HPV-16 DNA. All samples from normal tissue, benign, premalignant and CIN III lesions expressed HLA class I antigens. However, 15% of the invasive carcinomas completely lacked HLA-B and HLA-C antigen expression, 20% presented a heterogeneous pattern and 2 cases lacked HLA-B and HLA-C heavy chain but retained beta 2-microglobulin. MHC class I antigen expression on tumors was compared with clinical-pathological parameters. The absence of expression of HLA class I molecules was significantly associated with the Glanz histoprognostic index of malignancy. HPV-16 sequences were detected in 60% of the condylomas, 88% of the CIN I/II, 80% of the CIN III and 82% of the cervical carcinomas. Eight-six per cent of the tumors expressing HLA class I antigen presented HPV-16, whereas only 40% of the nonexpressing tumors did. Our results lead us to the following conclusions: a) HLA class I losses occurred when the tumor became invasive, and in tumors of a more aggressive histological type; b) The presence of HPV-16 was associated with tumors expressing HLA class I antigens.

Adenocarcinoma↗
PubMed1991

Pharmacokinetics and distribution of ketamine after extradural administration to dogs.

We have studied the pharmacokinetics and distribution of ketamine and its biotransformation products in dogs after extradural administration of ketamine at L4-5. The mean apparent uptake rate constants of ketamine for plasma and CSF were 4.17 (SD 1.84) and 5.15 (2.50) h-1, respectively. The concentrations of ketamine in CSF were greater than those found in plasma. The elimination half-life values of the parent drug for both biological fluids were similar (4.3 (2.96) h and 4.6 (3.31) h for plasma and CSF, respectively). The apparent formation rate constant of norketamine was greater than that of dehydronorketamine. However, the concentrations of the biotransformation products in CSF were smaller than those of the parent drug. These results are similar to the distribution of ketamine and its metabolites in different cerebral structures and tissues. The concentrations decreased in concert with the increase in polarity of the metabolites. A specific distribution for all compounds was observed. Ketamine showed a greater affinity for brainstem, while norketamine and dehydronorketamine were distributed mostly in cerebellum and kidney, respectively.

Anesthesia, Epidural↗
PubMed1991

Analgesic activity of a triterpene isolated from Scoparia dulcis L. (Vassourinha).

Analgesic and anti-inflammatory activities of water (WE) and ethanolic (EE) extracts of Scoparia dulcis L. were investigated in rats and mice, and compared to the effects induced by Glutinol, a triterpene isolated by purification of EE. Oral administration (p.o.) of either WE or EE (up to 2 g/kg) did not alter the normal spontaneous activity of mice and rats. The sleeping time induced by sodium pentobarbital (50 mg/kg, i.p.) was prolonged by 2 fold in mice pretreated with 0.5 g/kg EE, p.o. Neither extract altered the tail flick response of mice in immersion test, but previous administration of EE (0.5 g/kg, p.o.) reduced writhings induced by 0.8% acetic acid (0.1 ml/10 g, i.p.) in mice by 47%. EE (0.5 and 1 g/kg, p.o.) inhibited the paw edema induced by carrageenan in rats by respectively 46% and 58% after 2 h, being ineffective on the paw edema induced by dextran. No significant analgesic or anti-edema effects were detected in animals pretreated with WE (1 g/kg, p.o.). Administration of Glutinol (30 mg/kg, p.o.) reduced writhing induced by acetic acid in mice by 40% and the carrageenan induced paw edema in rats by 73%. The results indicate that the analgesic activity of S. dulcis L. may be explained by an anti-inflammatory activity probably related to the triterpene Glutinol.

Animals↗
PubMed1991

Cardiac glycosides isolated from the Indian-snuff, Maquira sclerophylla Ducke.

The hydroalcoholic extract of the powdered bark of the Indian-snuff Maquira sclerophylla Duck was purified by column chromatography in silica-gel and the major cardenolide isolated from preparative TLC was identified by 1H-NMR, 12C-NMR and IR analyses. The spectra showed that the active substance has strophanthidin as the aglycone.

Brazil↗