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Biomedical subjects

F Martinez

Publications and source records attributed to F Martinez.

At least 181 records · Page 10Linked to original sources
PubMed1986

Comparative study of the antihypertensive effect of verapamil and atenolol.

A clinical trial in 24 patients with essential arterial hypertension (14 women and 10 men, mean age 47.5) was conducted on a double-blind basis using a placebo, 240-mg verapamil and 100-mg atenolol daily. The total duration of the trial was 12 weeks: a 2-week washout period on placebo, a 4-week period on one of the trial drugs, a second 2-week weaning period and a further 4-week treatment period on the other trial drug. Stabilization of the hypertension was obtained in 80% of the patients on verapamil and 71% of the patients on atenolol both in the supine and upright positions; there was no significant difference between the 2 drugs. A moderate decrease in heart rate was obtained. Sinus bradycardia was observed in 3 patients on verapamil and 4 patients on atenolol. No instances of atrioventricular block were observed on electrocardiogram. No adverse effects were reported with verapamil and in only 1 patient taking atenolol. Adequate stabilization of hypertension appears possible in most patients with both verapamil and atenolol.

Adult↗
PubMed1986

An analysis of factors associated with ectopic pregnancy in a human in vitro fertilization program.

Between 1980 and 1985, in Monash University in vitro fertilization (IVF) program, ectopic pregnancy occurred in 10 of 256 IVF pregnancies. The incidence of ectopic pregnancy between 1983 and 1984 was 4% of the total pregnancies, or 4.2% of pregnancies excluding biochemical pregnancies. The incidence of ectopic pregnancy was distributed equally across the infertility classifications (tubal, idiopathic, male factor, and mixed). There appeared to be no relationship between superovulatory methods, endocrine changes before egg recovery, laparoscopic procedures, embryo transfer procedures, and number of embryos transferred. Nine of the ten patients were classified as having either tubal factor infertility before IVF or chronic tubal inflammation, which probably existed at the time of embryo replacement. No ectopic pregnancies were recorded in the 33 pregnancies obtained with superovulation with the use of clomiphene citrate alone. We were unable to identify a major predisposing factor for ectopic pregnancy in IVF.

Adult↗
PubMed1986

Rectification of the remnants of the leaflets--a new surgical technique to avoid periprosthetic leaks in aortic valve replacement.

During the last 12 years, we have used a modified suture technique for aortic valve replacement in 450 patients in order to avoid periprosthetic leaks. There were 420 survivors, and reoperation for periprosthetic leaks was necessary in no instance. The "secret" of our technique consists of the uniform distribution of the tensile forces among all sutures, eliminating uneven stresses that favors tearing of the tissues or rupture of the stitches.

Adolescent↗
PubMed1986

Detection of the LH surge for AID, AIH and embryo transfer using a twice daily urinary dip-stick assay.

The detection of the spontaneous LH surge in 12 infertile women being monitored for transfer of frozen-thawed or donor embryos was studied using plasma radioimmunoassay (RIA), urinary RIA and a dip-stick enzyme immunoassay. Ten of the 12 women had plasma LH surges and in all but one woman the dip-stick assay detected the LH surge to within 12 h of the plasma RIA. The urinary RIA detected the LH surge in only six of the 10 women. In two of these cases the surge was detected 24 h and 36 h later than by plasma RIA. The dip-stick assay has many advantages and could be usefully integrated as a mode of monitoring ovulation in infertility therapy.

Embryo Transfer↗
PubMed1985

Biochemical and morphologic effects of ethanol on fetuses from normally ovulating and superovulated mice.

To further our understanding about the teratogenicity of ethanol, we studied the changes produced by this compound in the incorporation of glucose 14C into several tissue fractions of 12-day mice fetuses and the morphologic alterations present at day 19 of gestation. Furthermore, to determine if the fetal toxicity of ethanol was modified by changes in the characteristics of the pregnancy, we performed similar biochemical and morphologic observations in fetuses from superovulated mice. Maternal ethanol administration caused biochemical alterations in the fetal tissues of both normally ovulating and superovulated mice, but it caused morphologic alterations predominantly in fetuses from superovulated animals. The prevalent morphologic alteration found in ethanol-treated animals was a hemorrhagic lesion dorsal to the lumbar or dorsal vertebrae. These results suggest that superovulation increases the susceptibility of the fetal mice tissues to the teratogenic effects of ethanol.

Abnormalities, Drug-Induced↗
PubMed1985

No influence of number of donor CFU-GM on granulocyte recovery in bone marrow transplantation for acute leukemia.

The possible interrelation between infused bone marrow CFU-GM and peripheral granulocyte recovery was studied in 16 patients transplanted for acute leukemia. The influence of several clinical events that could modify the graft fate were also analysed. Our results show that: 1) There was no correlation between the number of infused nucleated cells and granulocyte recovery. 2) There was no correlation between the number of infused CFU-GM and granulocyte regeneration. 3) There were significant differences between the day of engraftment in patients with clinically documented HSV infection compared to patients without infection.

Acute Disease↗
PubMed1985

New location of milk-of-calcium.

A case of milk-of-calcium with an exceptional location is reported. The characteristics of milk-of-calcium are presented, with stasis and urinary tract infection being the most important etiologic factors in this case. Structurally the stones are formed by a central core of calcium phosphate surrounded by magnesium-ammonium phosphate (struvite).

Adult↗
PubMed1985

Stimulatory effects of carbenicillin and ticarcillin on the adhesion and spreading of human polymorphonuclear leukocytes.

The in-vitro effects of ticarcillin and carbenicillin on adhesiveness, spreading, chemotaxis, phagocytosis and Candida-killing of human leukocytes have been comparatively studied. Adhesion and spreading of cells was increased by incubation with ticarcillin and carbenicillin. We found significant enlargement of surface and length measurements by optical and scanning electron microscopic examination. (P less than 0.0005). The number of cells was only significantly increased after exposure to ticarcillin (P less than 0.05). There were no modifications of chemotaxis, phagocytosis and Candida-killing capacity with respect to control values.

Candida↗
PubMed1984

Changes in plasma levels of protease and fibrinolytic inhibitors induced by treatment in acute myeloid leukemia.

We have studied the main protease inhibitors of leukocytes, alpha-1-protease (alpha 1-PI), alpha-1-antichymotrypsin (alpha 1-Achy) and alpha-2-macroglobulin (alpha 2-M), as well as different parameters of coagulation and fibrinolysis in 21 cases of acute nonlymphoblastic leukemia (ANLL) before, during and after therapy. Nine of the patients presented signs of DIC, 8 of whom belonged to subtype M3 and to subtype 1 M1. The initial alpha 1-PI and alpha 1-Achy levels, which were elevated, increased during the treatment period. There was no significant difference between patients with and without DIC. However, those leukemic patients with DIC showed a significant decrease in plasminogen (p less than 0.005) and fast antiplasmin (p less than 0.01) only during the treatment compared with DIC free patients. All DIC cases demonstrated circulating plasmin-antiplasmin complex (P-AP) both before and during treatment. Independent of a possible proteolytic action of leukocyte enzymes on clotting factors in the clinical course of ANLL (mainly M3 subtype), our results suggest an activation of plasmin-mediated fibrinolysis related to the activation of plasminogen by leukocytes, reactive DIC or both.

Adolescent↗
PubMed1984

Chemical intermediates in dopamine oxidation by tyrosinase, and kinetic studies of the process.

A minor pathway for dopamine oxidation to dopaminochrome, by tyrosinase, is proposed. Characterization of intermediates in this oxidative reaction and stoichiometric determination have both been undertaken. After oxidizing dopamine with mushroom tyrosinase or sodium periodate in a pH range from 6.0 to 7.0, it was spectrophotometrically possible to detect o-dopaminoquinone-H+ as the first intermediate in this pathway. The steps for dopamine transformation to dopaminochrome are as follows: dopamine----o-dopaminequinone-H+----o-dopaminequinone---- leukodopaminochrome--- - dopaminochrome. No participation of oxygen was detected in the conversion of leukodopaminochrome to dopaminochrome. Scanning spectroscopy and graphical analysis of the obtained spectra also verified that dopaminequinone-H+ was transformed into aminochrome in a constant ratio. The stoichiometry equation for this conversion is 2 o-dopaminequinone-H+----dopamine + dopaminochrome. The pathway for dopamine oxidation to dopaminochrome by tyrosinase has been studied as a system of various chemical reactions coupled to an enzymatic reaction. A theoretical and experimental kinetic approach is proposed for such a system; this type of mechanism has been named "Enzymatic-chemical-chemical" (EzCC). Rate constants for the implied chemical steps at different pH and temperature values have been evaluated from the measurement of the lag period arising from the accumulation of dopaminochrome that took place when dopamine was oxidized at acid pH. The thermodynamic activation parameters of the chemical steps, the deprotonation of dopaminequinone-H+ to dopaminequinone, and the internal cyclization of dopaminequinone to leukodopaminochrome have been calculated.

Basidiomycota↗
PubMed1984

A genetic basis for heterogeneity of asthma syndrome in pediatric ages: adenosine deaminase phenotypes.

Wheezing in children is characterized by at least two major syndromes: "wheezing associated with respiratory infections" and "atopic asthma." The distinction between these two forms is not easy as similarities exist between them. The purpose of this study was to try to differentiate between them. We determined the phenotype of adenosine deaminase (ADA) in 291 children ages 1 mo to 15 yr who had been affected by attacks of wheezing recently requiring clinical attention. The results demonstrated that the frequency of 2-1 ADA phenotype was significantly reduced in wheezers compared to control subjects. Among wheezers, the 2-1 ADA phenotype was normally represented under 5 yr of age but was particularly rare among asthmatic children 5 to 15 yr old. Thus ADA phenotypes may represent a genetic basis for some of the heterogeneity of the asthma syndromes in children.

Adenosine Deaminase↗
PubMed1984

Clinicopathologic and dysmorphic findings in recombinant chromosome 8 syndrome.

Clinical records, autopsy reports, and microscopic slides from 11 infants with the recombinant 8 syndrome, an inherited abnormality of chromosome 8 affecting Hispanics from New Mexico and Colorado, were evaluated. A prevalence of cardiac and genitourinary anomalies was found, while few central nervous system abnormalities were observed. Dysmorphic features associated with recombinant 8 syndrome are presented, with descriptions of the inheritance pattern and recurrence risk. Because recombinant 8 syndrome is a chromosomal disorder that will appear more and more frequently as kindreds enlarge, pathologists must be alert to its diagnostic characteristics and genetic implications.

Abnormalities, Multiple↗
PubMed1984

Prostaglandin receptors and hormonal actions on water fluxes in cultured canine renal cells (MDCK line).

An established cellular line (MDCK) derived from canine kidney showed specific binding for prostaglandin E2, both when the determination of specific binding was carried out in cells attached to a semipermeable support and when this binding was determined in suspended cells in a calcium-free medium. Specific binding for tritiated prostaglandin F2 alpha was also observed, and it was inhibited by increasing concentrations of non-radioactive PGF2 alpha in a dose-related pattern. Cross-reactivity between PGE2 binding and PGF2 alpha was present. Arginine-vasopressin induced an increase in the apical-to-basal water flux when applied to the basolateral surface. No change was observed when the hormone was in contact with the apical surface of the monolayer. Prostaglandin E2 also induced an increase in water flux, with a slower time course than that of arginine-vasopressin. The presence of PGE2 inhibited the increase in water flux induced by antidiuretic hormone. The results suggest that MDCK monolayers depict a physiological antagonism between ADH and prostaglandins which is similar to that observed in natural epithelia.

Animals↗
PubMed1983

Use of trophoblast cells in tissue culture for fetal chromosomal studies.

The objectives of this research were to determine optimal conditions for culturing trophoblast cells in vitro and to ascertain whether cells maintained under these conditions are an adequate source of material for fetal chromosome studies. Best results were obtained with the use of 1.25 X 10(6) cells in a total volume of 4 ml of M-199 medium that contained 20% calf serum and 1 mg/ml glucose, incubated in an atmosphere of 95% air and 5% carbon dioxide. Cytogenetic analysis was performed in trophoblast cultures 14 to 64 days old. In all cases it was possible to identify cells in metaphase which were adequate for karotyping. Evidence that the cultured cells were fetal in origin was provided by two cases in which chromosome abnormalities--46,XY,inv(18), and 47,XX, + 21--were identified both in the placental cultures and in leukocytes and fibroblasts from the fetus. The cytogenetic analysis was correct in the prediction of the fetal sex in seven cases; in two cases the prediction was questionable, and in two cases it was in error. The conclusion is that the use of trophoblast cells for fetal cytogenetic studies is not practical because of (1) difficulties in culturing the cells, (2) the low mitotic frequency of the cells in culture, and (3) contamination of the culture with maternal fibroblasts.

Cells, Cultured↗
PubMed1983

Aluminium-induced, reversible microcytic anemia in chronic renal failure: clinical and experimental studies.

Ten chronic hemodialysis patients with severe aluminium (Al) intoxication developed a microcytic anemia despite oral iron supplementation. Their microcytosis was reversible after deionization of the dialysis water. Ten age and sex matched hemodialysis patients who were not Al intoxicated but who had a comparable treatment schedule and time on dialysis had no such microcytosis. In order to investigate a possible direct role of Al we intoxicated uremic rats by daily (6/7 days a week) intraperitoneal injections of 30 nmoles/day of aluminium. After 3 months, the Al-intoxicated uremic rats had a significantly lower hematocrit (34.7%), hemoglobin (12.0 g/dl), and MCV (52.5 fl) than the control, vehicle-injected uremic animals (37.4%, 13.1 g/dl and 60.4 fl., respectively). The reticulocyte counts of the intoxicated rats were increased. Serum iron and transferrin iron binding capacity were unchanged. Thus aluminium intoxication of the uremic organism leads to a microcytic anemia possibly by interfering directly with normal hemoglobin synthesis.

Adult↗
PubMed1982

Effects of cimetidine on haematopoiesis in vitro.

The possible modifications in haematopoiesis induced by cimetidine were studied in normal bone marrow cultures in vitro. When cimetidine was added in the therapeutic range, there was no significant change in either granulocytic-macrophagic (CFU-GM) or erythroid (BFU-E) colony growth. However, when cimetidine was added to the culture at 2 to 25 times the therapeutic range, a small but significant inhibition of both types of colony growth was found. We conclude that cimetidine in the therapeutic range does not induce inhibition of haematopoiesis in vitro but does in doses above the therapeutic range when inhibition is dose-dependent.

Cimetidine↗