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C Solano

Publications and source records attributed to C Solano.

At least 73 records · Page 4Linked to original sources
PubMed1992

Automation of prothrombin time on the Cobas Fara II centrifugal analyser.

The automation of the prothrombin time using Low Turbidity Australian Reference Thromboplastin on the Cobas Fara II centrifugal analyser is described. Initially this test was programmed as a 2-step technique to mimic the reference manual method. However, the wide variation of Cobas Fara normal control values obtained with several different batches of the reagent was unacceptable. Investigation of 1-step techniques resulted in dramatic changes in the normal control values. These changes would consequently alter reference values and affect International Sensitivity Index (ISI) and International Normalized Ratio (INR) determinations. This paper stresses the necessity to fully assess all methodology variables when evaluating new reagents.

Blood Coagulation Tests↗
PubMed1992

Autologous bone marrow transplantation in 22 adult patients with lymphoblastic lymphoma responsive to conventional dose chemotherapy.

In order to clarify the role of autologous bone marrow transplantation in adult lymphoblastic lymphoma (LBL) patients we have conducted a retrospective multi-institutional Spanish survey. Twenty-two adult patients, 20 males, two females, age 14-52 years (median 25.5) with LBL were treated with high-dose chemoradiotherapy and autologous bone marrow support. Fourteen cases were transplanted in first complete remission (CR1) and eight with other chemosensitive status (four later CR, two partial remissions and two sensitive relapses). From the 14 cases transplanted in CR1, four had previous bone marrow involvement and one meningeal infiltration; eight cases were Ann-Arbor stage IV and fulfilled accepted high-risk criteria for relapse. The conditioning regimen consisted of cyclophosphamide (60 mg/kg x 2) and total body irradiation (9-12 Gy) in 16 cases and high dose chemotherapy in six. The procedure-related mortality was 9% (7% in CR1 patients). The actuarial 2-year overall survival for CR1 patients was 85% at a median follow-up of 19 months. Disease-free survival (DFS) was 77%. In patients with less favourable disease status the 2-year overall and DFS were 73% and 50% respectively. In this study the DFS in CR1 patients was not influenced by bone marrow involvement or high-risk criteria predictive for relapse. These results support the effectiveness of this procedure, mainly for patients in CR1.

Adolescent↗
PubMed1991

[Extrinsic compression of the right atrium due to a mediastinal germ-cell tumor].

A patient with a mediastinal mass detected by plain chest roentgenogram is presented. The echocardiographic-Doppler examination and the computed tomography precise the gross nature and extent of the tumour and its anatomical location producing obstruction of the right atrium and modifying the blood flow pattern in this chamber. The serum tumour markers and the transthoracic biopsy confirm the diagnosis of primary mediastinal germ cell tumour.

Adult↗
PubMed1990

Prediction of vitamin K response using the Echis time and Echis-prothrombin time ratio.

Echis carinatus venom contains proteases capable of activating both normal and descarboxy prothrombin. We showed this venom (Sigma) principally activates prothrombin with almost no factor X activation. Echis time in combination with prothrombin time can predict vitamin K responsiveness since the Echis time is usually normal in the presence of descarboxy prothrombin associated with vitamin K deficiency. 38 patients with abnormal routine prothrombin times (PT) had both coagulant and immunogenic factor II assays along with Echis times done before and after vitamin K. Of 22 patients responding to vitamin K, based on correction of PT, 21 had normal initial Echis times and of 16 not responding, 11 had abnormal Echis times, giving a sensitivity of 95.4% and specificity of 68.8% for vitamin K responsiveness. 90% of patients with a PT/Echis time ratio less than 1.3 and a prolonged Echis time did not correct their PTs with vitamin K therapy. The 5 non-responders with normal Echis times all showed normal initial coagulant and antigenic prothrombin, but 3 had low F V and/or F VII.

Blood Coagulation Disorders↗
PubMed1989

Incised wound margins caused by steel blades. Scanning electron microscopy to determine wound direction.

The aim of this paper has been to check the diagnostic ability of Scanning Electron Microscopy (S.E.M.) to determine wound direction. We have studied incised wound margins caused by steel blades in human skin samples from cadavers by S.E.M. It was found that a lateral accessory tail existed in 65% of the entrance edges. This finding was recorded in all the cases when wound direction was perpendicular to Lancer's lines of the skin area in which the wound was located. No similar finding in the exit tails was noticed. The depth and length of the wound margins was less accurate an index of the wound direction than a lateral accessory tail. We think that this finding could be useful in determining the entrance margin in incised wounds.

Animals↗
PubMed1979

Comparison of AMP deaminase from skeletal muscle of acidotic and normal rats.

The deamination of AMP by AMP aminohydrolase (EC 3.5.4.6.) serves as the major source of ammonia production in skeletal muscle. It has been suggested that the ammonia may serve either in a buffering capacity to combat acidosis due to the accumulation of lactic acid produced during prolonged muscular activity, or as a substrate for glutamine formation which can ultimately be utilized by the kidney in adapting to metabolic acidosis. In view of this proposal, the properties of the enzyme obtained from skeletal muscle of acidotic rats have been compared with the enzyme from normal muscle. The specific activity of AMP deaminase in crude homogenates of acidotic muscle was not significantly different from normal levels. The enzyme from acidotic muscle was purified to homogeneity and was found to be identical to the enzyme obtained from normal muscle by the criteria of electrophoretic mobility, pH optimum, molecular weight, sedimentation coefficient, subunit composition, amino acid composition, monovalent cation requirement, substrate saturation, and inhibition by ATP, Pi and creatine-P. Thus, if the enzyme functions to prevent acidosis, the ability to respond to changes in the intracellular environment which accompany acidosis must be built into the structure of the enzyme normally found in skeletal muscle. Three lines of evidence strongly support this viewpoint: (a) the rate of deamination is approximately 2-fold higher at pH 6.5 than at pH 7.0, (b) the activity increases linearly with a decrease in the adenylate energy charge, and (c) within the normal physiological range of the adenylate energy charge, the enzyme is operating at only 10--20% of its maximum capacity.

AMP Deaminase↗
PubMed1977

Rat muscle 5'-adenylic acid aminohydrolase. Role of K+ and adenylate energy charge in expression of kinetic and regulatory properties.

The kinetic and regulatory properties of homogeneous AMP deaminase from rat skeletal muscle have ben examined with particular emphasis on (a) the role of potassium ions in the expression of these properties and (b) the role of the adenylate energy charge in the regulation of AMP deaminase activity. Although the enzyme has an absolute requirement for K+, the concentration required for maximum activation is dependent on the concentration of substrate. At saturating levels of AMP (greater than or equal 2.0 mM) maximum activation is observed with 25 mM KCl, whereas at lower substrate concentrations (0.2 mM) approximately 50 mM KCl is needed for maximum activation. Conversely, the response of enzyme activity ot increasing levels of substrate is dependent on the level of potassium ions. At substrating concentrations of K+, the saturation curve for AMP is highly sigmoidal (nh=3.2) whereas at higher KCl concentrations, the apparent cooperativity between AMP sites is almost completely abolished (nh=1.5). The inhibition by a number of phosphorylated metabolites, including ATP, GTP, creatine-P, and P1, is likewise sensitive to the concentration of K+. These results suggest that a significant amount of interaction between K+ sites and both substrate and effector sites is required for the expression of the catalytic and regulatory properties of the enzyme. The specific effects of ATP, creatine-P, and P1 on the parameters of Km and Vmax indicate that each of these profile of AMP deaminase activity generated in response to variations in the adenylate energy charge shows that within the physiological range of energy charge (0.75 to 0.95), the activity increases linearly with decreasesing energy charge and is insensitive to both the total adenylate pool size and the presence of P1 and creatine-P. These data suggest that the most important factor in the regulation of AMP deaminase activity is the state of the energy charge rather than the absolute concentrations of the individual effectors.

AMP Deaminase↗