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C Mendoza

Publications and source records attributed to C Mendoza.

117 records · Page 7Linked to original sources
PubMedDate not supplied

Sperm plasma membrane integrity in fertile and infertile men.

Sperm plasma membrane characteristics were analysed by a combined method, the HOS-eosine test (HOS-E test), that consists of the hypoosmotic swelling test (HOS test), and the eosine-Y staining. Semen samples were categorized into four groups (Normo-, Oligo-, Astheno-, and Oligoasthenozoospermic) and subjected to the standard analysis (spermiogram), HOS test, eosine-nigrosine test (reflecting sperm viability); and HOS-E test. HOS-E test makes it possible to distinguish four groups of spermatozoa: type 1, HOS+/eosine-; type 2, HOS-/eosine-; type 3, HOS-/eosine+; and type 4, HOS+/eosine+. Normozoospermic samples showed 61.2 +/- 1.4% type 1, 9.2 +/- 0.8% type 2, 22.6 +/- 1.1% type 3, and 6.8 +/- 0.6% type 4 spermatozoa. Oligozoospermic samples showed no significant differences in these values, whereas asthenozoospermic samples showed a higher percentage of types 3 and 4 and a lower percentage of type 1. Oligoasthenozoospermic samples showed high percentages of types 2, 3, and 4 and a low percentage of type 1. Sperm plasma membrane integrity is a necessary condition for motility and fertilization. So, it is not surprising that semen samples with abnormal motility showed a HOS-E result indicative of a defective plasma membrane.

Cell Membrane↗
PubMedDate not supplied

Sperm plasma membrane integrity measurement: a combined method.

Sperm plasma membrane characteristics were measured by a combined method consisting of the hypo-osmotic swelling test and staining with either the eosine Y (HOS-eosine test) or propidium iodide dye (HOS-propidium test). Sperm samples were washed and resuspended in BWW medium (fraction I). Aliquots of the washed spermatozoa were treated by a swim-up technique to select motile spermatozoa (fraction II). After separation of motile cells, residual sperm pellets were treated separately (fraction III). These three fractions were subjected to the hypo-osmotic swelling test, lipid peroxidation measurement, and the HOS-eosine and HOS-propidium tests. The HOS-eosine test makes it possible to distinguish 4 types of spermatozoa: type 1: HOS+/eosine-; type 2: HOS-/eosine-; type 3: HOS-/eosine+ and type 4: HOS+/eosine+ (Fig. 1). HOS-propidium test shows equal results as HOS-eosine test. Fraction I spermatozoa showed 55.2 +/- 3.6% type 1; 12.6 +/- 1.0 type 2; 28.0 +/- 2.9 type 3; and 4.2 +/- 0.6 type 4 cells. Fraction II spermatozoa were characterized by high percentages of type 1 cells, low percentages of types 3 and 4, and very low values of lipid peroxidation (5 times smaller than fraction I). Fraction III showed a low percentage of type 1, a high percentages of the other types, and an enhanced value of lipid peroxidation (2 times higher than fraction I). The prognostic value of the HOS-eosine test was evaluated in an IVF programme. Preliminary results show that a high incidence of types 2 and 4 spermatozoa is often associated with fertilization failure.

Cell Membrane↗
PubMedDate not supplied

Intramuscular lorazepam versus pentobarbital premedication: a comparison of patient sedation, anxiolysis, and recall.

In a double-blind, controlled study in 40 veterans, IM lorazepam was significantly superior to IM pentobarbital as a preoperative sedative and in ability to suppress the memory of events of the operative day. A trend was noted (not statistically in this small series) toward greater patient acceptance of lorazepam. No important adverse effects or changes in vital signs occurred with either agent.

Adult↗
PubMedDate not supplied

[Sudden death in intermittent Wolff Parkinson White syndrome].

Sudden death is a rare condition in asymptomatic patients with asymptomatic intermittent Wolff Parkinson syndrome (WPW); for this reason it is believed that these patients should not undergo to radiofrequency ablation. We report an asymptomatic 44 year old man who developed ventricular fibrillation with a pre-excited RR interval less than 200 msec during atrial fibrillation, as a first manifestation of WPW syndrome. The Holter monitoring showed intermittent pre-excitation at low heart rate (70 bpm). During the electrophysiological study a successfully radiofrequency catheter ablation of a right posteroseptal accessory pathway was performed. We concluded that intermittent pre-excitation may not be used to identify patients who are at risk of sudden death. Radiofrequency catheter ablation should be recommended in those patients with a very high success rate, and a low incidence of serious complications.

Adult↗
PubMedDate not supplied

[Trans-surgical ablation of atrial flutter in patients treated with closure of atrial septal defect. Pilot project].

Atrial flutter is one of the most common arrhythmias in patients with atrial septal defect, after surgery 14% of patients can develop it and may be associated with high morbidity. In this study we performed prophylactic and therapeutic ablation of atrial flutter during atrial septal closure surgery drawing 4 lines; line 1, isthmus cavo-tricuspid, the area between the inferior vena cava and the tricuspid ring; line 2, the area between coronary sinus ostium and inferior vena cava; line 3, the area between tricuspid valve annulus and coronary sinus ostium; and line 4, the area between lateral atriotomy and atrial septal defect. Twenty-one patients were included, 6 (28.5%) patients had atrial flutter before surgery and 15 (71.4%) were in sinus rhythm. There were no new cases of atrial flutter, but at six months follow up 2 (33.3%) patients recidivated with atrial flutter. One patient developed high degree atrio-ventricular block and a pacemaker had to be implanted. Older age at the time of surgery and high systolic pulmonary pressure were significantly higher in those patients with atrial flutter before surgery and in patients with arrhythmias recurrence. Ablation of atrial flutter during atrial septal closure surgery can be a good option for the treatment and prevention of atrial arrhythmias, but more studies are still needed.

Adolescent↗
PubMedDate not supplied

[Increase of conjugated bilirubin in diabetics].

Three hundred patients were studied: 150 had NIDDM and the other 150 were non diabetics. Serum glucose and total and fractionated bilirrubin were measured in samples taken after night fasting. The mean glucose in the NIDDM group was 180.4 +/- 17.9 mg/dL (+/- SD) and 82.7 +/- 4.4 mg/dL in the non diabetic (p < 0.001). The levels of total bilirrubin were similar in both groups (0.84 +/- 0.04 vs 0.81 +/- 0.02 mg/dL, p > 0.40) but there were group differences in direct bilirrubin (NIDDM 0.52 +/- 0.03 vs 0.20 +/- 0.01 mg/dL, p < 0.001) and in indirect bilirrubin (NIDDM 0.32 +/- 0.03 vs 0.61 +/- 0.02 mg/dL, p < 0.001). Thus, 62% of the circulating bilirrubin was conjugated in the diabetics and only 25% in the non diabetics. We believe that at least part of the UDP-glucose pathway is altered in NIDDM and leads to an increase in the levels of glucouronic acid and, in turn, may cause a rise in direct bilirrubin at the expense of indirect bilirrubin.

Adult↗