PubMed Health⌕ Search

Biomedical subjects

F Gil

Publications and source records attributed to F Gil.

At least 55 records · Page 3Linked to original sources
PubMed1998

Magnetic resonance imaging of the normal canine larynx.

The purpose of this study was to define the normal anatomic structures in the canine larynx with magnetic resonance images. TI-weighted images were taken in the sagittal and transverse planes. The MR images were obtained comparing MR images to dissection planes. Magnetic resonance imaging provides excellent anatomic detail of laryngeal structures. Therefore, it is of value of diagnostic imaging of some respiratory diseases in the dog.

Animals↗
PubMed1998

A prefilled injection device for outreach tetanus immunization by Bolivian traditional birth attendants.

This study evaluated the performance, acceptability, and appropriateness of a new, single-use, prefilled injection device called UniJect for an outreach immunization application. Between April and June 1995, UniJect devices were used by 36 traditional birth attendants to administer tetanus toxoid injections to 2,240 pregnant women during routine, antenatal home visits in the Northern, Ichilos, and Warnes Districts of Santa Cruz, Bolivia. Because tetanus toxoid is relatively heat stable, the traditional birth attendants were able to keep the tetanus toxoid-filled UniJect devices in their homes for up to one month without refrigeration. The devices were stored, transported, and disposed of in an outreach carrier designed to reduce the risks of improper handling and disposal. Data were collected from injection recipients, traditional birth attendants, and supervisors via observation, questionnaires, and post-study interviews. The performance of the UniJect device and its acceptability among all groups was very high. The traditional birth attendants used UniJect properly and safely; there were no reports or observations of device misuse, reuse, or needle-stick. Advantages cited included the fact that the device required no assembly, offered assured sterility, and reduced vaccine wastage sometimes associated with multi-dose vials. The ability to store and transport the vaccine-filled devices without ice also greatly simplified logistics.

Bolivia↗
PubMed1998

The effect of fibrin glue patch in an in vitro model of postdural puncture leakage.

UNLABELLED: We studied the possibility of stopping a continuing transdural leakage with fibrin glue, a biologic adhesive, in an in vitro model. The model was made by sealing the bottom of a tube filled with saline to a height of 50 cm with a human lyophilized dural specimen. Dural punctures were performed with a 17-gauge Tuohy needle. The needle was then withdrawn, and 0.8 mL of fibrin glue was injected through the same needle to seal the defect. The column was refilled 3 min after sealing. The pressure in the intrathecal chamber was measured during the procedure. Macroscopic and microscopic histological studies of the dura and the fibrin plug were performed. In the five cases studied, the leak was sealed by the fibrin plug at closing pressures of 25-35 cm H2O, and no further leakage was detected after refilling. The dural specimens showed a fibrin glue plug stuck at the edges of the hole. We conclude that fibrin glue stops leakage of fluid from dural holes created by a 17-gauge Tuohy needle in an in vitro pressurized model. IMPLICATIONS: We explored the possibility of repairing a cerebrospinal fluid leak produced by an accidental dural puncture during epidural anesthesia by percutaneously injecting tissue adhesive in vitro. This technique seems promising for the prophylaxis and treatment of the headache associated with this leakage but requires further study in vivo.

Dura Mater↗
PubMed1998

Lack of clinical symptoms in an acute arsenic poisoning: an unusual case.

A 32-y-old woman was admitted to Granada University Hospital for attempted suicide by ingestion of an ant-killer containing 10% sodium arsenate and 5% pyrethrins. Neither gastrointestinal distress nor hepatic, renal, or neurologic disturbances were clinically observed. However, the presence of toxic levels of arsenic (14 mg/L) was confirmed by atomic absorption spectrophotometry in a sample of urine taken about 12 h after poisoning. An uneventful clinical course was observed, and the patient was discharged after 6 days upon her request. Long-term follow-up was unavailable. From a Medline search over the years 1985-1998 only one similar report also dealing with sodium arsenate was found. Different pathogenic hypotheses are discussed in the light of the clinical data.

Adult↗
PubMed1998

[Cardiocirculatory effects of intravenous anesthetic induction in an experimental model of acute hypovolemia].

OBJECTIVE: To evaluate the cardiovascular effects of ketamine, midazolam, thiopentone and propofol in acutely hypovolemic pigs and to determine whether the association of ketamine and midazolam offers any advantage. PATIENTS AND METHODS: Twenty-two Landrace-Large-White pigs. After monitoring was begun, acute hypovolemia was induced by means of rapid exsanguination of 30% of calculated volume. Hemodynamic variables were measured: a) at baseline; b) after exsanguination; c) 2 min after anesthetic induction; d) 10 min after anesthetic induction, and e) after reinfusion of the exsanguinated volume. RESULTS: All pressures, cardiac output, cardiac index, and mixed venous oxygen saturation fell significantly with the induction of hypovolemia. Heart rate, systemic vascular resistances and arteriovenous oxygen differential increased. Ten min after anesthetic induction, heart rate in the midazolam group was significantly lower than in the ketamine-midazolam group. Arterial pressures decreased significantly after anesthetic induction with all drugs. The decrease in systolic arterial pressure was smaller in thiopenthal-anesthetized pigs than in pigs receiving either midazolam or propofol at the 10 min recording. The decrease in mean arterial and diastolic pressure after 10 min was smaller with thiopental than with any other drug. The decrease in mean arterial pressure was less in the thiopental and ketamine-midazolam groups than in the others after reinfusion. Diastolic arterial pressure at 10 min and after reinfusion had decreased less in the thiopental and ketamine-midazolam groups than in the propofol group. After anesthetic induction, the post-hypovolemic figures for cardiac output and cardiac index held steady or changes were slightly accentuated, with no statistically significant differences among the groups. CONCLUSIONS: The intravenous anesthetics evaluated were detrimental to cardiovascular function in acute hypovolemic pigs. Low-dose thiopental and ketamine plus midazolam may be the anesthetics of choice in this setting. Propofol caused the greatest degree of hemodynamic instability.

Acute Disease↗
PubMed1997

Inhibition of paraoxonase activity in human liver microsomes by exposure to EDTA, metals and mercurials.

Inhibition of paraoxon hydrolase (paraoxonase) activity by 'in vitro' exposure to EDTA, Mg2+, Co2+, Ba2+, La3+, Zn2+, Cu2+, Hg2+, p-hydroxymercuribenzoate (p-OH-MB) and phenyl mercuric acetate (PMA) was investigated in human liver microsomes. Enzyme activity was totally inhibited by 1 mM EDTA in a time-dependent manner, in contrast to previous data obtained in rat liver where an EDTA-resistant fraction was detected. The possible influence of postmortem changes in these results was checked in a parallel experiment using rat livers with different postmortem intervals. From our results the existence in human liver of an EDTA-resistant fraction cannot be discarded. Ba, La and PMA showed immediate inhibition. By contrast the other compounds tested were time-dependent inhibitors. Ba and Zn showed the highest IC50 values. Cu and mercurials (Hg, p-OH-MB, PMA) were the most potent inhibitors of human liver paraoxonase. Kinetic analysis (Lineweaver-Burk and Dixon plots) indicated that different inhibitors exhibit different inhibition patterns: competitive (EDTA, Ba, La, Cu, p-OH-MB and PMA), non competitive (Zn) and mixed (Hg). The pretreatment of sample with dithiothreitol (DTT) protects against the inhibitory effect of mercurials. Furthermore after inhibition by mercurials the activity was restored by DTT. These results confirmed the essential role of the -SH groups to maintain the catalytic activity of paraoxonase and suggest the existence of two types of -SH groups that could differ in their localization.

Animals↗
PubMed1997

Purification and characterization of paraoxon hydrolase from rat liver.

Paraoxonase (paraoxon hydrolase), an enzyme that hydrolyses paraoxon (O,O-diethyl O-p-nitrophenyl phosphate), is located in mammals primarily in the serum and liver. Although considerable information is available regarding serum paraoxonase, little is known about the hepatic form of this enzyme. The present work represents the first study on the purification of rat liver paraoxonase. This enzyme has been purified 415-fold to apparent homogeneity with a final specific activity of 1370 units/mg using a protocol consisting of five steps: solubilization of the microsomal fraction, hydroxyapatite adsorption, chromatography on DEAE-Sepharose CL-6B, non-specific affinity chromatography on Cibacron Blue 3GA and anion exchange on Mono Q HR 5/5. The presence of Ca2+ and Triton X-100 in the buffers throughout the purification procedure was essential for maintaining enzyme activity. SDS/PAGE of the final preparation indicated a single protein-staining band with an apparent Mr of 45 000. N-terminal and internal amino acid sequences were determined and compared with those of paraoxonases from human and rabbit serum and mouse liver, showing a high similarity. The pH profile showed optimum activity at pH 8.5. The pH stability and heat inactivation of the enzyme were also studied. The Km for liver paraoxonase was 1.69 mM.

Animals↗
PubMed1997

[Anatomo-radiologic correlation of the head of the goat of the canary breed (Capra hircus L.)].

A radiologic and tomographic study was made of the cranioencephalic topography of canary goats of medium weight and size. In a first step, the exocranialis references corresponding to an axis designed at the level of the meatus acusticus externus and parallel to the basicranial axis were anatomically and radiologically defined. Conventional stereotaxic techniques were then used to reach the standard position of the head in order to obtain macroscopical cross sections at different levels perpendicular to the base of the cranium. In a second step, a tomographic study was made to confirm the design of the axis.

Animals↗
PubMed1996

The association of tooth lead content with dental health factors.

The purpose of this study was to determine the relationships of lead content in the human tooth with the prevalence of caries, dental plaque, pH of saliva, levels of Salivalis lactobacilli (SL) and Mutans streptococci (MS), degree of dental abrasion, tooth colour and toothbrushing frequency. A total of 220 teeth (one per person) were analysed using a microwave oven digestion procedure and lead content was measured by atomic absorption spectrometry. Tooth lead content followed a logarithmic-normal distribution and it increased with the prevalence of caries. Tooth lead concentrations were positively correlated with all the considered dental health factors except the pH of saliva, for which there was a significant negative correlation. Coloured teeth and teeth subject to abrasion showed the highest lead content. The highest number of colonies of SL and MS in saliva paralleled the highest lead tooth levels. Teeth obtained from irregular brushers presented higher tooth lead contents than subjects with a regular toothbrushing frequency. Multiple logistic regression analysis showed a significant association between tooth lead levels and dental plaque surface, Salivalis lactobacilli number, dental abrasion and dental colour. We conclude that accumulation of lead in teeth is associated with those dental health factors.

Adolescent↗
PubMed1996

Hereditary breast cancer risk: factors associated with the decision to undergo BRCA 1 testing.

The determination of tumoural genetic markers is the latest research priority in oncology. The high level of psychological distress observed in women at enhanced risk of breast cancer affects their willingness and readiness to bank DNA samples for BRCA 1 testing and the clinician's ability to engage in prevention measures such as mammography, breast clinical examination and breast self-examination. From psychological approach to oncology (psycho-oncology), it should be able to help identify factors that will increase breast cancer screening compliance (early breast cancer detection) and participation in genetic testing (BRCA 1 gene) for heritable breast cancer risk.

Breast Neoplasms↗
PubMed1995

Physical symptoms and psychological distress among patients with HIV infection.

There are many questions about the relationship between HIV-related symptoms and psychological distress, and how this relationship affects the immunological and clinical stage of illness. This article reviews the most recent research studies in this field, and encourages new research projects which will help in the management of physical and psychological symptoms associated with HIV infection.

Adult↗
PubMed1995

[Histochemical and morphometric study of the fibrillar population in the diaphragm muscle. I. Horse and dog].

By using m-ATPase techniques, under alkaline and acid pre-incubations, as well as metabolic techniques (alpha-MGPDH and NADH-TR), sections from the lumbar and costal portions of diaphragm muscle in horse and dog were analysed. Fibre samples were exposed to image-analysis observations in order to determine the lowest fibre diameter and obtain statistical data. The findings revealed that the lumbar portion of horse diaphragm consists of fibre types I, IIA and IIB; in the costal portion, the fibre type I and IIA were present. In the dog, the lumbar and costal portions consisted of fibre types I, IIA and IIC, which showed some specific histochemical characteristics. Some data concerning both morphometrical and statistical fibre-type analysis are presented.

Animals↗
PubMed1994

Dental lead levels in the Galician population, Spain.

The aim of this study was to investigate tooth lead concentrations in a Spanish population living in Coruña, Spain. A total of 220 teeth were analysed using a microwave oven digestion procedure and lead content was measured by atomic absorption spectrometry. Samples were classified according to age, sex, type of tooth, cause of extraction and place of residence. Tooth lead levels followed a logarithmic-normal distribution. The general geometric mean was 10.36 micrograms/g of tooth. There was a significant increase in teeth lead levels with advancing age. Permanent teeth showed higher values (13.09 +/- 1.07 micrograms/g, mean +/- S.E.M.) than deciduous teeth (3.96 +/- 1.07 micrograms/g). However, no differences were found between sexes. High lead concentrations were detected in pathological teeth, particularly in those with periodontal pathology, suggesting a relation between lead levels and dental disease. Nevertheless, teeth with caries did not show any significant lead increase. People living in urban areas of the coast had the highest lead teeth contamination. This is the first study in Spain which describes the tooth lead levels as a marker of lead exposure.

Adolescent↗
PubMed1994

Differences in the kinetic properties, effect of calcium and sensitivity to inhibitors of paraoxon hydrolase activity in rat plasma and microsomal fraction from rat liver.

The properties of a rat hepatic microsomal enzyme that hydrolyses O,O-diethyl-p-nitrophenylphosphate (paraoxon) were studied and compared to the paraoxon hydrolase activity found in rat plasma. The pH stability for both enzyme activities was optimum between pH 6.0 and 9.0. An overall analysis of the data showed that the microsomal fraction was less resistant to the effect of the pH than plasma. The kinetic constants for heat inactivation evaluated for paraoxonase in rat plasma and liver microsomal fraction indicate that paraoxonase tends to inactivate faster in rat liver microsomes than in rat plasma. The apparent activation energies of the heat inactivation process were 77.7 and 61.1 kcal/mol for rat plasma and microsomal fraction, respectively. Enzyme activity was lost after both dialysis and incubation with EDTA and partially restored by the addition of calcium. In rat plasma samples the requirement for calcium was absolute (essential activator) while in the microsomal fraction the reaction may occur, to a minimum extent, in the absence of the activator (non-essential activator). Calcium restored 85% activity when added immediately after EDTA; restored activity decreased when the time interval between addition of EDTA and calcium was increased. Other metals were not able to restore activity previously inhibited by EDTA or dialysis. The response to several inhibitors (EDTA, Mn, Co, Zn, Ba, Mg, Cu, La, Hg and p-hydroxy-mercuribenzoate) of rat plasma and microsomal fraction was studied, determining the type of inhibition and the inhibition constants. Plasma enzyme was always more resistant than liver sample to the effect of the inhibitors and showed different types of inhibition than the liver microsomal fraction. In general we found more differences than analogies between the rat plasma and liver enzyme which suggests the presence of two enzymes or two different forms of the same enzyme. Furthermore the existence of an EDTA-resistant fraction in rat liver microsomes suggests that more than one enzyme capable of hydrolysing paraoxon is present in the microsomal fraction of rat liver.

Animals↗
PubMed1994

Production and regeneration of protoplasts from the Y-phase of the human pathogenic fungus Paracoccidioides brasiliensis.

Protoplasts of Y-cells and partially converted M-cells from several human isolates of Paracoccidioides brasiliensis were obtained with a combined enzyme system containing Novozym 234 and a chitinase. A laboratory made extract from Trichoderma harzianum CBS-345-33 supplemented with chitinase induced the release of protoplasts from partially converted M-cells but not from established Y-cells. A similar yield of protoplasts (1-2 x 10(5) ml-1 after 16 h) was produced by using either enzymatic system. Protoplasts regenerated on nutrient gelatin at 23 degrees C at a frequency of 0.1%.

Cell Wall↗
PubMed1993

Microwave oven digestion procedure for atomic absorption spectrometry analysis of bone and teeth.

The purpose of this study was to develop a new method for determination of the mineral element in teeth and bone using a microwave digestion procedure coupled to atomic absorption spectrometry. Samples were ashed at 450 degrees C for 4.5 h and subsequently digested in a microwave oven at maximum power (600 W) for 10 s using a Teflon closed Parr bomb. This method permits the rapid dissolution of the biological samples, avoiding operations such as slicing and cutting which often introduce alterations in sample homogeneity and may contribute to their contamination. The analysis of Na, K, Ca, Mg, Fe, Zn, Ba, Cd and Pb showed good reproducibility, precision and accuracy as compared with the certified values for the IAEA H-5 animal bone. Average concentration for those elements in permanent teeth obtained from children aged 11-18 years by orthodontics are given.

Adolescent↗
PubMed1993

Inhibition of phosphatidylcholine biosynthesis and cell proliferation in Trypanosoma cruzi by ajoene, an antiplatelet compound isolated from garlic.

Ajoene [(E,Z)-4,5,9-trithiadodeca-1,6,11-triene 9-oxide], a potent antiplatelet compound derived from garlic, inhibits the proliferation of both epimastigotes and amastigotes of Trypanosoma cruzi, the causative agent of Chagas' disease. The growth of the epimastigote form was immediately arrested by 80 microM ajoene, while 100 microM induced cell lysis in 24 hr. In the amastigote form proliferating inside VERO cells, 40 microM ajoene was sufficient to eradicate the parasite from the host cells in 96 hr. Growth inhibition of the epimastigotes was accompanied by a gross alteration of the phospholipid composition of the treated cells in which phosphatidylcholine (PC), the major phospholipid class present in control cells, dropped to the least abundant phospholipid in cells treated with 60 microM ajoene for 96 hr, while its immediate precursor, phosphatidylethanolamine (PE), became the predominant species; this was correlated with a marked drop in the incorporation of [14C-U]acetate in PC and a corresponding increase in PE. Concomitant with the change in the phospholipid headgroup composition of the cells, the fatty acids esterified to this lipid fraction underwent a dramatic alteration due to the increase in the content of saturated fatty acids and a marked reduction in the content of linoleic (18:2) acid, which is the predominant fatty acid in control cells. We also found that ajoene inhibited the de novo synthesis of neutral lipids and, in particular, of sterols in the epimastigotes, but the resultant changes in the sterol composition were not sufficient to explain the antiproliferative effects of the drug. Electron-microscopy showed a concentration-dependent alteration of intracellular membranous structures, particularly the mitochondrion and endoplasmatic reticulum. The results suggest that one important factor associated with the antiproliferative effects of ajoene against T. cruzi is its specific alteration of the phospholipid composition of these cells.

Animals↗