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Biomedical subjects

J Ruiz

Publications and source records attributed to J Ruiz.

At least 325 records · Page 18Linked to original sources

[Viper bites].

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Adrenal Cortex Hormones↗

Abolition of mevinolin-induced growth inhibition in human fibroblasts following transformation by simian virus 40.

The basal level of the gene expression and the activity of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase was higher in SV40-transformed human fibroblasts (90-VA VI) than in normal ones (HDF). In both these cell types mevinolin (25 microM) caused an 85-90% depression of HMG CoA reductase activity and of the incorporation of [3H]acetate into sterols. In HDF this was coupled to an efficient block of cell growth, whereas the growth of 90-VA VI was only slightly reduced by mevinolin. In HDF, mevinolin (25 microM) also abolished essentially all dilichol synthesis, as measured by incorporation of [3H]acetate. In contrast, dolichol synthesis remained unaltered, or was increased, in mevinolin-treated 90-VA VI. We suggest that these different responses of dolichol synthesis may depend on different substrate affinities of the rate-limiting enzyme in the dolichol pathway. However, if 90-VA VI was treated with 25-hydroxycholesterol (25-OH), an alternative inhibitor of HMG CoA reductase, the cellular growth as well as dolichol synthesis was significantly decreased. Since the inhibitory effect of 25OH on HMG CoA reductase activity did not exceed that of mevinolin, it seems that 25-OH, besides HMG CoA reductase, inhibits steps distal to HMG CoA reductase. This notion was further supported by the finding that addition of mevalonate did not prevent the 25-OH-induced growth inhibition. However, if dolichol was added along with 25-OH, the block was partially prevented, indicating that a critical level of de novo synthesis of dolichol for cellular growth.

Cell Division↗

[Evaluation of ceftazidime monotherapy in Pseudomonas aeruginosa bacteremias. Prospective study].

Twenty-six episodes of Pseudomonas aeruginosa bacteremia treated with intravenous ceftazidime, 4-6 g/day were evaluated. Treatment was begun within the first 24 hours after the isolation of the microorganism and was maintained for 10-12 days. In two patients with neutropenia amikacin was added during the initial 48-72 hours until the susceptibility to ceftazidime was known. All isolates were sensitive to ceftazidime. The most common underlying diseases were neoplasia (12), diabetes with stroke (4), neurosurgical and vascular procedures (4), rheumatoid arthritis (2), burns (2), cor pulmonale (1), and hypertension (1). The origins of bacteremia were urinary (12), pulmonary (9), and unknown (5). The infection was hospital-acquired in 77% and community-acquired in 23%. A critical clinical status and the presence of complications were significantly (p less than 0.01) associated with an increased mortality rate. Clinical outcome was good in 18/26 (70%), with a 30% mortality rate. The microbiological evolution showed 14 eradications, 6 persistences, 3 relapses and 3 colonizations. Resistance did not develop during therapy. Ceftazidime may be a good alternative therapy for these severe infections, although wider comparative studies are required for a better evaluation.

Adult↗

Iron status in patients receiving erythropoietin for dialysis-associated anemia.

Adequate body iron stores are crucial to assuring rapid and complete response to recombinant human erythropoietin (rHuEPO). In the present study, markers of iron storage were examined in 27 patients with normochromic, normocytic anemia undergoing acute rHuEPO (150 to 300 U/kg t.i.w.) treatment for anemia. We calculated projected iron needed for new hemoglobin synthesis from the difference between initial and target hemoglobin concentrations, initial iron reserves available from initial serum ferritin levels, and net projected surplus or deficit from the difference between needs and reserves. Of 22 patients predicted to develop iron deficiency (mean projected deficit 268 +/- 70 mg), 20 developed evidence of exhausted iron stores (transferrin %sat less than 16 or ferritin less than 30 micrograms/liter) before reaching target hemoglobin; two predicted to become deficient (projected deficit less than 100 mg) did not; and all five predicted to avoid iron deficiency (mean projected surplus 177 +/- 20 mg) remained iron replete. During acute rHuEPO therapy net body iron balance remained neutral in patients receiving no iron supplements and increased 5 mg/kg in patients prescribed oral ferrous sulfate. However, in patients given iron dextran i.v. less than 60% of elemental iron administered became measurable as iron stores or usable for hemoglobin synthesis.

Anemia↗

Recovery of motile sperm using the migration-sedimentation technique in an in-vitro fertilization-embryo transfer programme.

Sperm washing techniques, based on the swim-up principle used before inseminating the human oocyte in in-vitro fertilization and embryo transfer programmes (IVF-ET), usually require prior centrifugation which causes damage to the sperm cell. A technique is described for separating sperm at laboratory temperature based on sperm migration--sedimentation principles, using two concentric tubes and recovering 70-90% forward-moving cells. A group of 17 patients is presented who were managed with this method. The results were 85% fertilization rate, 4% polyspermia and six clinical pregnancies.

Cell Separation↗

A prospective double-blind trial of a low molecular weight heparin once daily compared with conventional low-dose heparin three times daily to prevent pulmonary embolism and venous thrombosis in patients with hip fracture.

In a randomized, prospective, double-blind trial, the effect of conventional low-dose heparin (5,000 units every 8 hours) was compared with that of a low molecular weight fragment (2165 LMWH, Kabi Vitrum AB, starting 2,500 units 2 hr before surgery, and then 5,000 units subcutaneously every morning for 9 days). A total of 90 patients admitted because of hip fracture fulfilled the inclusion criteria and were analyzed for development of pulmonary embolism and deep vein thrombosis: 46 patients were included in the low molecular weight heparin (LMWH) group, and 44 in the conventional heparin group. Two and three, respectively, died before diagnostic tests were performed. In the remaining patients a ventilation-perfusion lung scan was performed 8 days after intervention. In the first 57 patients studied a bilateral ascending venography was performed on the ninth day only if clinical symptoms suggested a deep venous thrombosis. Because of the rate of venous thrombosis detected in those patients was unexpectedly low, venography was requested in the remaining 33 patients, even if the screening tests were negative. Pulmonary embolism occurred in six patients, all in the LMWH group. Deep vein thrombosis occurred in 14 patients in the LMWH group and in six patients in the conventional heparin group. Both differences are statistically significant. Mortality did not differ between the groups, nor did haemorrhagic complications. Our findings suggest that, in patients with hip fracture, LMWH is not useful at the dosage used.

Aged↗

Use of ceftriaxone in the treatment of bacterial infections in cirrhotic patients.

Sixty-two episodes of bacterial infection were studied in 51 cirrhotic patients. 2 g of ceftriaxone (active ingredient of Rocephin) were given intravenously once daily for 7-10 days. The infections were pneumonia, bacteremia, spontaneous bacterial peritonitis, urinary infection and others. Good responses were seen in 90% of the cases.

Adult↗

Recurrent pulmonary embolism. A prospective study.

We have prospectively studied a series of 121 consecutive patients with venous thromboembolism (38 with pulmonary embolism, 83 with venous thrombosis of the lower extremities) searching for recurrences of pulmonary embolism despite adequate heparin therapy. A baseline ventilation-perfusion lung scan was obtained initially in every patient, whether the original diagnosis was pulmonary embolism or venous thrombosis. Repeat chest roentgenograms and lung scans were obtained routinely at eight days of heparin treatment. The primary trial endpoints were a finding of a clinically apparent recurrent pulmonary embolism, or laboratory evidence of subclinical pulmonary embolism. Eight items of clinical and laboratory information were recorded at admission and then correlated with the lung scan results. Recurrences were seen in seven of 38 patients with an original diagnosis of pulmonary embolism, and in five of 83 patients admitted because of venous thrombosis (p = 0.034). Recurrences were also more frequent in patients with a free-floating thrombus on venography (p = 0.014). The risk of new defects in patients with venous thrombosis and without free-floating thrombus was 3.05 percent, venous thrombosis with free-floating thrombus, 13.33 percent; patients with pulmonary embolism without free-floating thrombus, 11.42 percent; and with free-floating thrombus, 38.67 percent. Venography seems thus mandatory in patients with pulmonary embolism, as it recognizes a subgroup of patients at a high risk of recurrences.

Adult↗

[Corynebacterium D2-induced encrusted cystitis].

Two cases of patients with cystitis cystica secondary to urine infection, caused by resistant corynebacterium D2, are presented. The clinical features were important dysuria and frequency, alkaline urine Ph (Ph 8 and 9). The urine cultures were obtained with the standard techniques, after 72 hours of incubation. They were treated with vancomycin, ciprofloxacin and hydroxinamic acid with good response.

Aged↗

Amiodarone toxicity: recurrence of interstitial pneumonitis after withdrawal of the drug.

Amiodarone hydrochloride, an iodinated benzofuran derivative, is effective for treatment of supraventricular and ventricular arrhythmias. Pulmonary fibrosis has been reported after treatment with this drug. We present a patient with amiodarone pulmonary toxicity, who initially responded to corticosteroid therapy, but who developed a clinical relapse two months after withdrawal of the drug.

Amiodarone↗