PubMed Health⌕ Search

Biomedical subjects

L López

Publications and source records attributed to L López.

At least 109 records · Page 6Linked to original sources
PubMed1980

Quantification of plasminogen activator activity associated with herpesvirus-transformed cells.

Herpesvirus-transformed cell lines were examined for plasminogen activator (PA) activity using a quantitative assay. Previous results of cold fibrin overlay assays indicated that herpesvirus-transformed hamster cell lines produce fibrinolytic activity. Quantification of this activity involved the use of an 125I-fibrin lysis assay in which medium previously incubated with transformed or normal cells was tested for its ability to lyse 125I-fibrin polymers. This assay indicated an enhanced production of plasminogen-dependent fibrinolytic activity by transformed hamster cells compared to hamster embryo fibroblasts. The kinetics of secretion failed to reveal a significant difference in plasminogen activator activity in cells transformed by either herpes simplex virus types 1 or 2 (HSV-1 or HSV-2); however, transformed cells exhibited a significant increase in activity over non-transformed cells. Further characterization of PA activity associated with cells transformed by HSV-1 or HSV-2 has revealed that the protease is secreted and can function extracellularly. Extracellular PA activity produced by HSV-transformed cells is detected more efficiently than the cell-associated enzyme. Extracellular PA can be induced in two different species of cells by infection with partially inactivated HSV-2. Lytic infection of human embryo lung cells by HSV-2 strain 333 did not enhance activity, but infection of these cells with virus inactivated by u.v. irradiation resulted in increased PA levels from the cells. Increased enzyme levels were also detected in hamster embryo fibroblasts infected with partially inactivated virus. Further investigation of this enzyme function may determine whether increased levels of protease will indicate oncogenic transformation in vitro by herpesviruses.

Animals↗
PubMedDate not supplied

[Infection and colonization by Scedosporium prolificans].

BACKGROUND: Scedosporium prolificans is a dematiaceous fungus that is known to cause a wide spectrum of infections in humans, bearing a severity and a prognosis that is relationed with the patients immune status. METHODS: A retrospective review was made of the clinical charts of all patients who developed positive S. prolificans cultures in our centre from 1990 to 2000. Isolates were identified by colonial morphology and microscopic features. The in vitro susceptibility was evaluated using the microdilution method according to NCCLS. RESULTS: S. prolificans was isolated in 15 patients. Eight were affected with cystic fibrosis and the isolation of S. prolificans in their airways did not worsen their clinical status. Among the remaining 7 cases there were five leukemic patients with neutropenia and two immunocompetent hosts with cutaneous infection and endocarditis. Four of five neutropenic patients died of sudden sepsis and S. prolificans was isolated from blood cultures made a few days before their death, and the fifth neutropenic case suffered a bilateral pneumonia with improving course probably due to recovery from neutropenia. As to the immunocompetent group the clinical course was good in the cutaneous infection case, but the endocarditis case died four days after the antifungical therapy was started. All the isolates tested were found to be resistant to amphotericin, 5 flucytosine, fluconazole, itraconazole, voriconazole, miconazole and terbinafine. CONCLUSIONS: Scedosporium prolificans is a fungal pathogen that colonizes the airways of patients affected with cystic fibrosis. It can also cause a wide variety of infections, whose severity and prognosis depends on the patients immune status. Due to the resistance of this fungus to antifungal drugs, the therapeutic options are limited. Only with the correction of neutropenia and surgery in local infections in immunocompetent hosts it has been possible to cure these infections.

Acute Disease↗
PubMedDate not supplied

[Primary spontaneous pneumothorax. A retrospective study of 495 cases].

We conducted a retrospective study of patients treated in our department for primary spontaneous pneumothorax (PSP) between 1986 and 1993. The 495 patients were between 12 and 81 years old (mean 28.2 years). Four hundred fifteen (83.8%) were men and 80 (16.2%) were women. PSP was in the right lung in 262 cases (52.9%) and in the left lung in 215 (43.5%). Both sides were affected in 18 cases (3.6%). The initial treatment was pleural drainage; small caliber drains were used in 85 and no associated complications were observed. On 185 occasions (37.3%), patients required surgical repair as a result of air leaks, recurrence or acute hemorrhage. There were postsurgical complications in 15 cases (8.1%) but no recurrences or deaths after surgery. We observed no significant differences in the number of recurrences after use of conventional drains or small caliber drains. Nor were there differences in mean time of hospital stay or complications after conventional surgery or video assisted surgery, a technique that has only recently been introduced. We conclude that PSP responds well to treatment with pleural drains and that small caliber catheters offer a good alternative for treating first episodes. Surgery is indicated when there is recurrence or when air leaks are persistent. At present, video assisted thoracoscopic surgery has successfully replaced axillary thoracotomy for most patients.

Adolescent↗
PubMedDate not supplied

Chronic portal hypertension in the rat by triple-portal stenosing ligation.

A surgical technique based on the development of a triple stenosing ligation is used to worsen the complications inherent to the prehepatic chronic portal hypertension. The results have been compared with those obtained in rats with a single-portal stenosing ligation. An increase (p <.05) in the body, liver, spleen, and kidney weights as well as a decrease (p <.001) in the testes weight to body weight ratio were produced in both groups of animals. In addition, the variability in the obtained weights, particularly in the liver weight, stands out. The incidence of portosystemic and portohepatic collateral circulation and of the mesenteric venous vasculopathy increases in the animals with triple-portal stenosing ligation. The new proposed technique is a valid alternative to the classic one that used single portal stenosing ligation.

Animals↗
PubMedDate not supplied

Intertrochanteric-subtrochanteric fractures: treatment with the long Gamma nail.

OBJECTIVE: To evaluate the outcome of the treatment of intertrochanteric-subtrochanteric fractures (subtrochanteric fractures with extension into the greater trochanter and the piriformis fossa) using the long Gamma nail. DESIGN: Prospective, consecutive. SETTING: Multicenter (private clinics). PATIENTS: Fifty-two closed intertrochanteric-subtrochanteric fractures in nonpathologic bone in fifty-two consecutive patients with a mean age of forty-five years (range, 18 to 91 years). INTERVENTION: Closed reduction and internal fixation with the long Gamma nail. MAIN OUTCOME MEASUREMENTS: Analysis of clinical and radiologic results with emphasis on the incidence of complications. Outcome assessment comparing the preinjury status of every patient with the status at a minimum follow-up of twelve months. RESULTS: At one year, seven patients had died and two other patients were lost to follow-up. Thus, forty-three of the fifty-two patients completed a prospective follow-up averaging sixteen months (range, 12 to 31 months). All fractures united within an average of 4.3 months (range, 3 to 6.5 months). Mechanical complications (breakage of the distal locking bolts) occurred in one fracture. Two patients had more than 5 degrees but less than 10 degrees of deformity in varus and more than one but less than 2.5 centimeters of shortening; two had more than 5 degrees of deformity in varus; and two had up to one centimeter of shortening. Two patients had other severe injuries that influenced the end result. Thirty-four of the remaining forty-one patients (82.9 percent) were restored to their preinjury status. There was no direct relationship between the radiologic and the functional results: an excellent radiologic result was not uniformly associated with an excellent functional outcome. CONCLUSIONS: Closed reduction and long Gamma nailing of intertrochanteric-subtrochanteric fractures enables the orthopaedic surgeon to treat these fractures with a minimally invasive procedure and a negligible rate of mechanical complications. The rate of union was 100 percent in this series. The rate of restitution to the preinjury status was high.

Adolescent↗
PubMedDate not supplied

[Evaluation of 2 techniques for ventilation support during single-lung ventilation].

In a group of 22 patients undergoing thoracotomy we compared two techniques of ventilatory assistance to the nondependent lung during single lung ventilation. We simultaneously administered a 0.5% FiO2 to the dependent lung. We used a CPAP system with continuous O2 flow limited by an underwater valve at a pressure of +5 cmH2O. We performed 33 ventilatory assistances: in 15 cases to the nondependent lung (CPAP group) and in 18 patients to the lower lobe of the nondependent lung (lobar CPAP group). Evaluation of both techniques was performed by means of arterial blood gas measurement and the mean values were compared using the student's t test. During single lung ventilation the PaO2 in CPAP group increased from 85.86 +/- 22.28 mmHg to 155.52 +/- 59.54 mmHg (p less than 0.001) and in the lobar CPAP series it increased from 88.75 +/- 24.34 mmHg to 122.36 +/- 43.21 mmHg (p less than 0.01). In 11 out of the 22 patients we firstly applied the lobar CPAP and thereafter the CPAP to the whole lung in order to compare the efficacy of both techniques in the same patient. The PaO2 during single lung ventilation was 86.9 +/- 22.7 mmHg and it increased to 111.1 +/- 37.9 mmHg after lobar CPAP (p less than 0.01) ant to 163.3 +/- 64 mmHg after total lung CPAP ventilation (p less than 0.001). Our results confirm the usefulness of both techniques and they indicate that CPAP to the whole nondependent lung is the most effective.

Adult↗
PubMedDate not supplied

[Lower respiratory infections caused by beta hemolytic group A Streptococcus].

Three patients with beta-hemolytic group A streptococcal pneumonia were described. We emphasize the opportunistic pathogenic ability of the microorganism in the lower respiratory tract, and we describe the possible pathogenic mechanisms as well as the more frequent symptoms and complications.

Adolescent↗