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S Engel

Publications and source records attributed to S Engel.

137 records · Page 8Linked to original sources
PubMedDate not supplied

Angiotensin-converting enzyme and other peptidolytic enzymes in human semen and relations to its spermatologic parameters.

Angiotensin-converting enzyme (ACE) and other enzymes of the renin-angiotensin system (RAS) occur in human semen in high activities. In contrast to bull ejaculates, not all zinc-dependent metallopeptidases are found to be in close correlation to the microscopically determined semen parameters; such a relationship was established only partly for the ACE. On the other hand, the RAS-dependent spermatozoa-bound enzymes, inclusive ACE, uniformly show negative correlations to the spermatologic parameters of human semen. These results, for the first time, point to different functions of the sperm-cell-bound (testicular) and of the seminal plasma (pulmonary) ACE activities.

Amino Acid Sequence↗
PubMedDate not supplied

The spermatozoal volume as indicative of the plasma membrane integrity (modification of the hypoosmotic swelling test). I. Methods.

The aim of the present study was to establish a more differentiating indicator of plasma membrane integrity of spermatozoa than the classic version of the hypoosmotic swelling test according to Jeyendraan. Spermatozoa were prepared by density gradient centrifugation (90% Percoll) to select 'fertilization competent' spermatozoa only. After a second washing procedure sufficiently pure sperm cell suspensions were obtained. The volume distributions of these sperm cells were measured with a Coulter Counter at 25 degrees C after adaptation in 300 mosmolar NaCl solution resp. 150 mosmolar NaCl solution for 5 min. These volume distributions showed significantly different patterns for the isotonic and hypotonic stress situation in the simple salt solution. Moreover, the comparison of the response to hypoosmotic stress showed more than four reproducible characteristic patterns, promising well differentiated results for different sperm populations. The new method for the detection of hypoosmotic swelling effect might be a real and valuable functional parameter.

Cell Membrane↗
PubMedDate not supplied

The spermatozoal volume as indicative of the plasma membrane integrity (modification of the hypoosmotic swelling test). II. Diagnostic approach.

If using a method of statistical sifting based on the Kolmogoroff-Smirnov test for differentiation of volume distribution curves of a modified HOS-test, different curve types are obtained under isotonic as well as under hypotonic conditions. Arrangement of spermatological parameters of the relevant ejaculates according to the individual curve types reveals significant differences for motility. No correlation can be seen with the results of the microscopic HOS-test. Consequences for the use of the modified HOS-test in medical practice are discussed.

Cell Membrane↗
PubMedDate not supplied

Diabetes care needs of Hispanic patients treated at inner-city neighborhood clinics in New York City.

The charts of 254 Hispanic patients were selected from a sample of 321 patients with diabetes in four urban clinics that received federal funding to provide medical care in underserved communities. A standardized chart-audit protocol was used to assess the process of healthcare delivery and the presence of diabetes-associated comorbidities and complications in patients. Inconsistent recognition of obesity (11% identified vs 59% present), hyperlipidemia (17% identified vs 69% present), and renal dysfunction (3.5% identified vs 16% present) was evident on chart review. We also found inadequate compliance with current recommendations for diabetes care with respect to routine health screenings for diabetes-related complications, recognition of comorbid diagnoses, and referral of patients for recommended specialty consultations. Issues specific to the varied Hispanic populations may need to be considered to improve the delivery of diabetes care for the growing Hispanic population with diabetes.

Community Health Centers↗
PubMedDate not supplied

[Significance of linear cervix mucus penetration for the evaluation of spermatozoa quality].

Linear mucus penetration of spermatozoa from 75 arbitrary selected men was evaluated using a non-commercial bovine cervix mucus preparation in the same way as Penetrak, but using round glass capillary tubes instead of flat plastic tubes. The mean penetration value was 28.7 +/- 7.10 mm in 90 min and the mean sperm density 36.0 +/- 22.79 x 10(6) ml. Mucus penetration was more correlated to sperm density (r = 0.6) than to any other semen parameter. Consequently it seems to be necessary to evaluate a sliding discrimination index for adequate penetration rate depending on sperm density (regression line and confidence interval). Numerical methods for comparison of penetration rates are suggested.

Animals↗
PubMedDate not supplied

Ureaplasma urealyticum and male infertility: an animal model: II. Morphologic changes of testicular tissue at light microscopic level and electron microscopic findings.

Testicular biopsies were obtained from Wistar rats that had been infected artificially with Ureaplasma urealyticum, serotype 3. Approximately 50% of the biopsy specimens obtained 3 and 6 months after infection showed degeneration of the germinal epithelium, giant cell formation and Leydig cell hyperplasia. Electron microscopic studies revealed striking alterations of Sertoli cells, germ cells, and Leydig cells as well as ureaplasma organisms inside the seminiferous tubules. The changes noted in the ertoli cells were apparent as early as one week after infection.

Animals↗
PubMedDate not supplied

Ureaplasma urealyticum and male infertility: an animal model. I. Artificial infection, breeding experiments and histological preparation of organs.

Male Wistar rats were infected with Ureaplasma urealyticum, serotype 3 or 7, by injecting broth containing organisms into the urinary bladder following laparatomy. Animals were sacrificed 3, 7 and 21 days after infection. Ureaplasmas were detected in the organs of the genital tract by culture in 43% (serotype 3) and in 60% (serotype 7) of the animals. Type-specific ureaplasma antigen was detected in the genital organs in 44% (serotype 3) and 45% (serotype 7) of the animals. Control animals injected with sterile bouillon were negative for organisms and antigen. Male Wistar rats artificially infected with Ureaplasma urealyticum, serotype 3, were mated 3 and 6 months after infection with ureaplasma free female rats. The mating experiment revealed a smaller mean litter size and a lower birth weight in the offspring of infected males compared with the control animals, but no general influence on the fertility of infected animals.

Animals↗
PubMedDate not supplied

[Change in sodium and potassium concentration in human seminal plasma infected experimentally with Ureaplasma urealyticum].

The concentration of sodium and potassium ions was measured by flame photometry in human seminal plasma and human sperm cells as well as in a sperm cell suspension infected experimentally with Ureaplasma urealyticum during incubation as long as 22 hours. The sodium concentration is 86.2 +/- 21.97 mmol/l cells in sperm cells and 120.8 +/- 15.87 mM in seminal plasma. The potassium concentration is 33.2 +/- 16.35 mmol/l cells in sperm cells and 26.7 +/- 4.92 mM in seminal plasma. The sodium concentration decreased considerably in the suspension medium of sperm cells during the first hour of incubation and increased again subsequently. The potassium concentration in the suspension medium changed only little. The sodium concentration in the infected sperm cell suspension was insignificantly increased compared with the mycoplasma-free controls. The potassium concentration was slightly higher in the infected specimens than in the controls. There was no mycoplasma-induced effect on the concentration of sodium and potassium in the sperm suspension after experimental infection.

Humans↗
PubMedDate not supplied

[The relation between sperm motility and the content of unsaturated fatty acids as well as the osmotic behavior of human spermatozoa].

The relations between sperm motility and the content of lipids and fatty acids in sperm cells were investigated. In addition the osmotic volume changes of sperm cells were studied, by determination of progressive sperm motility, measurement of relative concentration of lipid-peroxy radicals in seminal plasma using chemoluminescence technique, gas-chromatographic determination of fatty acid pattern in sperm cells and in seminal plasma and by electronic measurement of the sperm cell volume. The impulse installment of chemoluminescence increased during the time of storage of the ejaculate. In contrast, this phenomenon was not observed in pure seminal plasma prepared by centrifugation immediately after liquefaction. The pattern of phospholipids and free fatty acids changed during storage of the ejaculate both in sperm cells and in seminal plasma. Sperm cells showed a significant increase of volume under hypotonic stress. The increase of volume is more distinct in spermatozoa with high progressive motility as in spermatozoa with low progressive motility. The determination of initial and late progressive motility enables the differentiation of two groups of sperm populations: one group with a medium initial motility and a normal decrease of motility during the following time and another group with excellent initial motility and an extreme decrease of motility following. The second group is characterized by an especially distinct increase of volume under hypotonic conditions.

Fatty Acids, Unsaturated↗
PubMedDate not supplied

Indications and results of extra-intracranial arterial bypasses.

410 patients with transient ischemic attacks (TIA), prolonged reversible neurologic deficits (PRIND), progressive and completed strokes were treated surgically with a superficial temporal artery-middle cerebral artery-extra-intracranial arterial bypass (STAMCA EIAB). Angiography and echo-flow-scans showed 92% of these grafts to be patent. Ninety-three patients suffered from TIA's, 57 from PRIND, 21 from progressive strokes, and 239 from completed strokes. In 53-70% of the 239 patients with completed strokes, there was improvement or complete regression of the neurological symptoms, following an EIAB. The mortality and morbidity rates were low. We believe that the clinical indications for EIAB include: TIA, PRIND and completed strokes (at an appropriate time after the event). Contraindications are: cerebral ischemia at the acute edema stage, advanced intracranial small vessel occlusive disease, completed stroke without any tendency to improvement, multiple vascular processes, severe static neurological deficits of long duration, serious cardio-vascular and pulmonary diseases, including long-standing hypertension.

Adult↗