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Biomedical subjects

R Sanchez

Publications and source records attributed to R Sanchez.

At least 199 records · Page 11Linked to original sources
PubMedDate not supplied

A new method for evaluation of the acrosome reaction in viable human spermatozoa.

The acrosome reaction of human spermatozoa was induced by changes of temperature. Spermatozoa were collected from fertile donors and a patient group, and selected by the "swim-up" method. The spermatozoa were treated in two different ways: Protocol I: 24 hours at room temperature followed by additional incubation at 37 degrees C for 3 hours (control), and protocol II: 24 hours at 4 degrees C followed by additional incubation at 37 degrees C for 3 hours. The acrosome reaction of the viable spermatozoa was evaluated by a new method utilizing indirect immunofluorescence with anti-outer acrosomal membrane antibodies and exposure to a hypo-osmotic medium. In fertile donors as well as in the patient group, significant induction of the acrosome reaction (20%) was evident after exposure to low temperature (4 degrees C). The spontaneous rate of acrosome reaction in the control group was below 7%.

Acrosome↗
PubMedDate not supplied

Demonstration of acrosomal membranes using the hypo-osmotic swelling test.

The state of the acrosomal membranes in human spermatozoa was studied by means of the hypo-osmotic swelling test and indirect immunofluorescence using anti-boar outer acrosomal membrane antibodies. The swelling phenomenon observed in the acrosomal region was characterized by expansion of the plasma membrane without modification of the outer acrosomal membrane.

Acrosome↗
PubMedDate not supplied

Sustained blood pressure elevation to lower body compression in pigs and dogs.

Inflatable suits were constructed for lower body compression in pigs and dogs. The suit for pigs encompassed hindquarters and part of the abdomen, and the smaller suit for dogs compressed only the hindquarters, leaving free the abdominal cavity. In conscious, diazepam-pretreated pigs, the compression lasted 30 minutes; during that period the blood pressure increased 50/38 mm Hg over the baseline. In chloralose-anesthetized dogs, the compression was extended to 3 hours; the blood pressure increase was 44/53 mm Hg. Blood pressure fell to the baseline immediately after decompression in both animals. In both species the substantial blood pressure increase was due to an increase of vascular resistance; this did not induced the expected baroreceptor-mediated bradycardia. In dogs, the blood pressure increase was accompanied by a large increase of plasma norepinephrine (from 179 to 975 pg/ml). To test whether the increase of vascular resistance reflected the mechanical compression of the vessels under the suit, animals were pretreated with trimethaphan. In pigs the trimethaphan substantially decreased the vascular resistance and the blood pressure response. This indicated that a portion of the vasoconstriction occurred in areas outside the suit. Lower body compression is a new model to cause prolonged blood pressure elevation by noninvasive and nonpharmacologic means. The mechanism of the blood pressure elevation requires further investigation.

Abdomen↗
PubMedDate not supplied

In vitro interactions of eutherian ova/spermatozoa: significance for orientation/binding of gametes.

Ova are observed in vitro to rotate counterclockwise immediately following sperm attachment. This phenomenon was examined in both human-hamster and hamster-hamster systems. The counterclockwise rotation has been found to be directly proportional to the efficiency of in vitro penetration or fertilization. These observations indicate that the eutherian ova possess a definite polarity and that the sperm attachment follow a given geometry.

Animals↗
PubMedDate not supplied

Influence of incubation time/temperature on acrosome reaction/sperm penetration assay.

The acrosomal status of human spermatozoa was studied in relation to the score of the sperm penetration assay (SPA) at low-temperature (4 degrees C) incubation for induction and synchronization of the acrosome reaction (AR) and the incubation time of spermatozoa in conventional SPA. Spermatozoa were collected from 18 patients, selected by the "swim-up" method and treated in three different ways: (1) short-term incubation group (SIG): 3 h incubation at 37 degrees C, and (2) long-term incubation group (LIG): 20 h incubation at 37 degrees C, and (3) low temperature group (LTG): 24 h incubation at 4 degrees C followed by additional incubation at 37 degrees C for 3 h. The conventional methods of incubation, i.e. SIG (3 h) and LIG (20 h) did not show any significant differences as evaluated by the sperm penetration rate and the number of decondensing sperm heads per oocyte. In contrast, in the LTG all parameters were significantly increased, especially those of penetration rate (p less than 0.0005) and decondensing sperm heads per oocyte (p less than 0.0005). The percentage of AR significantly increased (p less than 0.0005) in the LTG (14.7%) compared with SIG (6.1%) and LIG (10.6%). A significant correlation was demonstrated between AR and the parameters used for evaluation of the SPA. The penetration rate (Spearman test, r = 0.462, n = 54, p less than 0.003) was the most significant parameter correlated with AR. It would appear that only human spermatozoa having completed AR are capable of fusing with the zona-free hamster ova.(ABSTRACT TRUNCATED AT 250 WORDS)

Acrosome↗
PubMedDate not supplied

Effect of anesthesia on sperm motility in gamete intrafallopian transfer.

The existence of a motility-inhibiting substance in human peritoneal fluid (hPF) has been demonstrated. The results of this study indicate that this factor from hPF is a heat-resistant, volatile molecule with a very small molecular mass (e.g., halothane, which is used for general anesthesia in laparoscopic GIFT). This may be the reason for the conflicting results concerning pregnancy rates in gamete intrafallopian transfer.

Anesthetics↗
PubMedDate not supplied

The electron microscopic features of sinus histiocytosis with massive lymphadenopathy: a study of 11 cases.

Eleven cases of sinus histiocytosis with massive lymphadenopathy (SHML) involving lymph nodes were studied electron microscopically. Histiocytes were the most conspicuous element of the infiltrate. They could be divided into small and large forms, although transitions were apparent among them. Most of the small histiocytes were located in the medullary cords. The large histiocytes were predominantly seen within sinuses and were subdivided into two types on the basis of their appearance. The most distinctive feature of these histiocytes was the presence of lymphocytes, plasma cells, and neutrophils within their cytoplasm. Other cells present in the infiltrate were lymphocytes, plasma cells, and occasional neutrophils and mast cells. Blood vessels were prominent throughout. Virus particles, bacteria, and Langerhans' granules were consistently absent. No morphologic clues were provided by this study as to the etiology of this disorder.

Adolescent↗
PubMedDate not supplied

Professional partnerships in primary care practice.

Professional partnerships in pediatric primary care produce opportunities for blending nursing and medical roles to offer optimal health care to children and families. During the Sixth Annual Pediatric Nursing Conference, held October 4-7, 1990 in San Francisco, issues of role delineation, reimbursement or salary schedules, prescriptive authority, on-call status, malpractice coverage, and hospital privileges were discussed among a distinguished panel of PNPs and physicians.

Humans↗
PubMedDate not supplied

[Mollicutes in male infertility: is antibiotic therapy indicated?].

Mollicutes are frequently isolated from sperma of infertile men. The potential effect on the fertility of mollicute infection is controversial as is antibiotic therapy. In our andrological patients, the prevalence of mollicutes is approximately 10%. To evaluate the benefit of antibiotic therapy, we investigated two groups of patients: group 1-patients with positive or negative mollicute cultures and normal spermiogram; morphological changes on spermatozoa were particularly evaluated (n = 40); group 2 - patients with positive mollicute cultures treated with doxycycline or erythromycin. Sperm parameters were analysed before and after treatment (n = 20). When infected and non-infected sperma from group 1 were compared, the only difference found was an alteration of the sperm tail (p less than 0.005). Light microscopy and electron microscopy (EM) often revealed coiled tails which were probably due to adhesion of mollicutes (EM). The most frequently observed pathology in group 2 was found in patients with teratoasthenozoospermia. Compared with the post-therapy spermiogram, a significant difference was only observed in spermatozoal morphology (p less than 0.005). Therefore, we conclude that mollicutes produce important alterations in the human spermatozoal morphology, especially in the tail which appears in a spiral form. Since teratozoospermia is considered to be an important factor of infertility in man, antibiotic therapy is recommended in cases of mollicute involvement.

Bacteria↗
PubMedDate not supplied

Programme of education for obese patients. Preliminary results after one year.

We have evaluated the effects of a Programme of education for Obese Patients with a duration of 12 hours on weight loss and the modification of other indices for cardiovascular risk in 88 obese patients, during the first year of therapy. The BMI dropped from 33.1 +/- 0.2 Kg/m2 to 31.7 +/- 0.7 (p less than 0.01) and 30.9 +/- 0.7) (p less than 0.01) at 5 and 10 weeks respectively, stabilizing subsequently at 35 and at 55 weeks. This was accompanied by a decrease of the triglycerides levels (141 +/- 9 vs 111 +/- 6 mg/dl; p less than 0.01) and of the total cholesterol/HDL-cholesterol ratio (4.7 +/- 0.3 vs 4.2 +/- 0.12; p less than 0.05), as well as of the values for systolic blood pressure (143 +/- 3 vs 121 +/- 3 mm Hg; p less than 0.05) and diastolic blood pressure 81 +/- 2 vs 64 +/- 1 mm Hg; p less than 0.01) at the end of the study. In terms of OGTT, initially 23 patients were classified as diabetic (BMI 32 +/- 0.9 Kg/m2), 25 presented intolerance to carbohydrates (BMI 34.1 +/- 1.6 Kg/m2) and 40 were normal (BMI 33.2 +/- 1.2 Kg/m2). The weight loss in the first 5 weeks was less in patients with diabetes then in those with carbohydrate intolerance and in the normal patients (2.2 vs 3.7 vs 5.9 Kg; p less than 0.01). From the 10th week on no differences were recorded.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗
PubMedDate not supplied

[Metabolic acidosis and intravenous injections of fat emulsions (role of phospholipids. Experimental study)].

In explanation of metabolic acidosis during parenteral nutrition, the authors considered the supply of H+ ions by fat emulsion, containing phospholipids of egg or soy. During intravenous infusions of 24 grams of lecithins to two healthy subjects, they observed an increased output H+ ions in urine, about 74,05 and 75,88 mEq, and a metabolic acidosis of the plasma. The theorically forcasted supply of production was 74,6 mEq. Indeed the metabolism of phospholipids supplies phosphoric ions (PO4H3), giving H+ ions at pH 7,40. The most used fat emulsions are able to give between 37 (intralipid 10%) and 61 (lipihysan 15%) mEq of H+ ions/liter.

Acidosis↗