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F Jorquera

Publications and source records attributed to F Jorquera.

32 records · Page 2Linked to original sources
PubMed1999

Composite cervicofacial flap for reconstruction of complex cheek defects.

The authors present the reconstructive technique for complex cheek defects using the composite cervicofacial flap and study the possibilities, advantages, disadvantages, and results that can be expected. The design follows the classic outline of Mustardé's flap. The skin is undermined for 2 cm anterior to the ear, then after incision of the superficial musculoaponeurotic system (SMAS), undermining is continued below the plane of the SMAS, level with the facial nerve branches. It is continued forward to the facial vessels, which give rise to branches that ensure the blood supply of this composite flap and contribute to its high reliability. In the cervical region, undermining is done beneath the platysma, which is transected transversely in the lower cervical region to allow good upward mobility and satisfactory transposition of the flap. The flap is adapted to the defect and the medial suture line is placed as near as possible to the medial limit of the cheek aesthetic unit. The authors carried out a retrospective study of 7 patients with complex facial reconstruction after excision of malignant lesions. The defects measured from 4x4 cm to 9x7 cm. In 4 patients excision included the periosteum, and in 1 patient excision involved the entire thickness and removed the entire anterior half of the cheek. In 4 patients reconstruction involved the cheek and eyelid. In spite of the advanced age of the patients (88, 69, 91, 67, 70, 82, and 59 years), there was no distal edge necrosis. The only complication was a single case of facial paresis, which resolved spontaneously. The results were considered very good in all 7 patients. The authors conclude that the composite flap increases the possibilities of the cervicofacial flap. It is more mobile, more reliable, thicker, and more adaptable. It can be used in complex cheek defects that involve the periosteum, or even in full-thickness defects. The quality of the results obtained using this flap represents a considerable advance in facial reconstruction.

Aged↗
PubMed1998

The effect of age and sex on metabolism and urinary excretion of antipyrine.

BACKGROUND: Drug-metabolizing capacity is generally reduced in the elderly. The purpose of this investigation was to study antipyrine clearance and metabolite excretion in old subjects of both sexes. METHODS: Saliva clearance of antipyrine and the production clearances of antipyrine metabolites were studied in young and elderly volunteers of both sexes. Seventy-six elderly subjects (mean age 81 years) were compared with a group of 24 young subjects (mean age 29 years). RESULTS: After oral administration, salivary antipyrine clearance declined with age in both males and females, whether or not this variable was corrected for weight, and antipyrine half-life was significantly prolonged in elderly groups of either sex. The percentage urinary excretion of the antipyrine metabolites (hydroxymethylantipyrine, HMA; norantipyrine, NORA; and 4-hydroxyantipyrine, OHA) was reduced at 48 h in the elderly compared to young subjects by 23%, 31%, and 10%, respectively, in males, and by 41%, 41%, and 24%, respectively, in females. The formation clearance of HMA was reduced by 47% in males and by 52% in females. NORA clearance declined by 42 and 56%, respectively, in males and females. A decrease of 30% in males and 44% in females was observed in OHA clearance. CONCLUSIONS: The findings suggest that aging leads to altered disposition of antipyrine in both males and females and that the main metabolic pathways of the compound are not different in the elderly.

Administration, Oral↗
PubMed1998

[Parital cutaneous necrosis of the abdominal wall after cesarean section].

The authors report an original case of large cutaneous necrosis of the abdominal wall following a first cesarean section in a patient with a background of pemphigoid gestationis. There was no direct skin burn nor infection of the dermis and this necrosis is typical of venous suffering. The mechanism is debated, probably the thrombosis of the superficial inferior epigastric vein due to the spreading out of a monopolar coagulation current. A one-step treatment was done using a wide excision and an abdominal advancement flap. This surgical technique allowed a fast cicatrisation and led to a very good long-term esthetical result.

Abdominal Muscles↗
PubMed1996

Accuracy of the one-sample method for determination of antipyrine clearance in elderly subjects.

The purpose of this study was to evaluate the validity of the one-sample abbreviated method for determination of the pharmacokinetic parameters of antipyrine in the elderly. Antipyrine pharmacokinetics were studied in 15 elderly women (mean age 86 years). Antipyrine (1 g) was administered orally and pharmacokinetic parameters were determined by the one-sample (24 h) and multiple-sample (3, 6, 9, 12 and 24 h) methods. Mean antipyrine clearance for the one-sample study (19.72 +/- 1.51) was almost identical to that obtained with the multiple-sample approach (20.73 +/- 1.57), and the two methods were very well correlated (r = 0.989). Relative standard deviations between individual clearances values for multiple-sample vs. one-sample studies averaged 1.6%. Values of elimination half-life were likewise very similar for the abbreviated (17.41 +/- 1.21) and complete (17.99 +/- 1.09) methods, with a significant correlation (r = 0.857). Although values were underestimated by 10% in the one-sample approach, no difference in the volume of distribution with the multiple-sample study was observed. When the unbiased volume of distribution value was determined from the total elimination curve against time, the influence of biased volume of distribution resulted in a 5.1% deviation in antipyrine clearance in the one sample method. The findings indicate that antipyrine pharmacokinetic parameters can be estimated with reasonable precision and accuracy in the elderly using a simplified one-sample procedure.

Administration, Oral↗
PubMed1996

Influence of nutrition on liver oxidative metabolism.

The liver plays a major role in the disposition of the majority of drugs. This is due to the presence of several drug-metabolizing enzyme systems, including a group of membrane-bound mixed-function oxidative enzymes, mainly the cytochrome P450 system. Hepatic oxidative capacity can be assessed by changes in antipyrine metabolism. Different drugs and other factors may induce or inhibit the cytochrome P450-dependent system. This effect is important in terms of the efficacy or toxicity of drugs that are substrates for the system. Microsomal oxidation in animals fed with protein-deficient diets is depressed. The mixed-function oxidase activity recovers after a hyperproteic diet or the addition of lipids. Similar findings have been reported in patients with protein-calorie malnutrition, although results in the elderly are conflicting. Different studies have revealed that microsomal oxidation is impaired by total parenteral nutrition and that this effect is absent when changing the caloric source from carbohydrates to a conventional amino acid solution or after lipid addition, especially when administered as medium-chain/long-chain triglyceride mixtures. Peripheral parenteral nutrition appears to increase antipyrine clearance.

Cytochrome P-450 Enzyme System↗
PubMed1995

Effects of aging on antipyrine clearance: predictive factors of metabolizing capacity.

The purpose of this study was to identify variables that can account for the decline of antipyrine clearance (CLAP) in elderly adults and that may help predict a reduction in metabolizing capacity. For comparison, ClAP was determined in 177 elderly (mean age 82 years) and 25 young (mean age 29 years) volunteers. Antipyrine (1 g) was administered orally and ClAP was determined by the one-sample saliva method. Mean ClAP was reduced by 38% and antipyrine half-life increased by 64% in old subjects. Multiple regression analysis of ClAP revealed an independent value for age, serum aspartate transaminase (AST), and height in the elderly. The independent variables collectively accounted for 27% of the variance explained. Age, high serum AST, use of diuretics, and no consumption of drugs known to stimulate oxidative metabolism were selected by multivariate analysis (logistic model) as independent predictors of a low metabolizing capacity. The findings indicate that factors other than age may contribute to impaired hepatic oxidative metabolism in the elderly.

Adult↗
PubMed1995

Assessment of antipyrine kinetics from saliva or plasma: influence of age.

The purpose of this study was to investigate whether antipyrine estimation in saliva provides valid information on plasma antipyrine clearance (APCl) and can be useful as an index of changes in drug metabolism with age. Antipyrine kinetics was studied in 93 elderly (mean age 82 years) and 23 young (mean age 29 years) volunteers. Plasma antipyrine half-life (APt1/2) increased and plasma APCl declined with age. No significant difference between plasma- and saliva-derived parameters was found in either young or old subjects. However, the saliva/plasma ACCl ratio tended to increase with age. A highly significant correlation between saliva and plasma APCl or APt1/2 was found in young subjects. Values were less closely related in the elderly and the slope of the saliva/plasma APCl relationship was significantly different in both groups of subjects. Residual variance was higher in the regressions corresponding to the elderly. The findings in the study indicate that the relationship between saliva and plasma kinetics in young subjects becomes less reproducible with age.

Administration, Oral↗
PubMedDate not supplied

Antipyrine clearance in surgical patients maintained on hypocaloric peripheral parenteral nutrition.

BACKGROUND: Antipyrine clearance (CLAP) constitutes a sensitive indicator of hepatic microsomal enzyme activity providing specific information on hepatic function. The purpose of this study was to evaluate the influence of hypocaloric peripheral parenteral nutrition on CLAP in patients receiving nutrition support after elective surgery. METHODS: CLAP was measured in 15 patients before elective gastrointestinal surgery and 6 days after the surgery. Antipyrine (1 g) was administered orally, and CLAP was determined by the one-sample method. Subjects received a postoperative 786 kcal/d regimen providing 66 g of amino acid per day and 133 g of glucose per day for 5 days. Nutritional status was evaluated by anthropometric parameters. A control group of 15 patients received no postoperative hypocaloric peripheral parenteral nutrition but received conventional fluid therapy. RESULTS: Mean CLAP was increased by 61% (0.66 +/- 0.06 mL/min.kg-1 body wt vs 0.41 +/- 0.05 mL/min.kg-1 body wt in the preoperative period; p < .001), and antipyrine half-life was reduced by 42% (10.9 +/- 1.0 hours vs 18.9 +/- 2.0 hours; p < .001) after 5 days of hypocaloric peripheral parenteral nutrition. No significant modification was shown among control patients in CLAP (0.54 +/- 0.07 mL/min.kg-1 body wt vs 0.46 +/- 0.05 mL/min.kg-1 body wt in the preoperative period) or in antipyrine half-life (14.0 +/- 1.4 hours vs 16.5 +/- 1.8 hours). No significant correlation was observed between CLAP changes and those for the nutritional status of the patients. CONCLUSIONS: The results of our study indicate that oxidative drug-metabolizing capacity is increased in surgical patients maintained on hypocaloric peripheral parenteral nutrition. Clinicians should be conscious of the potential of this effect for altering the efficacy or toxicity of many therapeutic agents.

Adult↗
PubMedDate not supplied

[Effects of glutamine on antioxidants systems and hepatic detoxification in rats: influence of formulation].

GOALS: The goal of this study is to assess the effect that supplementing parenteral diets with L-glutamine or with L-alanyl-L-glutamine has on the balance of oxidants/antioxidants in the liver and on detoxification systems mediated by P-450 cytochrome in rats. MATERIAL AND METHODS: Central catheters were inserted in the animals (n = 60) and they were randomly assigned to one of the following groups: a control group (C) with oral feeding and I.V. infusion of saline solution, a total parenteral nutrition group without glutamine (TPN without GLN), a parenteral nutrition group with glutamine supplement (TPN GLN), and a total parenteral nutrition group with a supplement of alanine-glutamine dipeptide (20 g/L) (TPN ALA-GLN). The parenteral nutrition provided was all isocaloric and isonitrogenated, and the infusions were administered at a speed of 2 ml/h over 5 days. RESULTS: In the animals of the group without GLN, the liver concentration of glutathione was reduced while the levels of thiobarbituric acid reaction products (TBARS) increased. Supplementing with either glutamine or alanine-glutamine normalized the levels of glutathione but the TBARS levels only fell in the group with the dipeptide. This effect was parallel to the partial recovery of the antioxidant enzyme activities analyzed. The liver concentrations of P-450 cytochrome, P-450 cytochrome dependent mono-oxygenases and the clearance of antipyrine were not modified by the supplements of glutamine or alanine-glutamine. CONCLUSIONS: Our data suggest a greater protection by alanine-glutamine supplements against the injury produced by free radicals during TPN and the absence of any effect with either glutamine or alanine-glutamine supplements on the oxidative metabolism of the liver.

Animals↗