Search PubMedSearch

Biomedical subjects

J E Davis

Publications and source records attributed to J E Davis.

At least 19 recordsLinked to original sources

Male sterilization.

This review of recent information and advances in the area of male sterilization deals with recent epidemiologic studies that discuss potential ill effects hypothesized to be a result of vasectomy, including carcinoma of the prostate and carcinoma of the testicle. Rebuttals to these hypotheses are presented. Recent advances in techniques of vasectomy including the "no-scalpel" vasectomy technique and open-ended vasectomy are presented, including the rationale for their use. A good deal of attention is given to postvasectomy follow-up, particularly the use of the technique of measuring numbers of ejaculations following vasectomy rather than the period of time afterward to determine when a man is sterile. The final two sections deal with complications of vasectomy and the most recent percentages on reversing vasectomy with particular reference to return of sperm to the ejaculate and pregnancy rates.

Aftercare

Can quality of life be evaluated?

A multidisciplinary committee of the Veterans Administration sought to evaluate quality of life as related to long-term care by developing possible measurements of the concept.

Health Facilities

Flushing of distal vas during vasectomy: current status and review of literature.

Vas irrigation during vasectomy, to effect immediate sterility or to shorten the interval between vasectomy and sterility, has received increasing attention in recent years. A review of the literature on vas irrigation is presented. Topics discussed include the effectiveness of various irrigants and irrigation methods, method and technical failures, and evidence of increased risks of recanalization, inflammation, tissue damage, and infection. Stored sperm and their location after vasectomy are explored. Suggested mechanisms for the action of irrigants are reviewed, and another mechanism is proposed. Variations in study results and our incomplete understanding of vas and seminal vesicle physiology during ejaculation (compounded by individual variations) require more investigation before large clinical trials are initiated.

Acriflavine

Paraduodenal hernia: an unusual cause of renal displacement.

Exploration of a retroperitoneal mass displacing the right kidney and lumbar paravertebral lymph nodes revealed a paraduodenal hernia. Paraduodenal hernias are explained in detail, the differential diagnosis of retroperitoneal masses is presented and the diagnostic modalities are described.

Duodenal Diseases

Glycosylated hemoglobins and diabetes mellitus.

Glycosylated hemoglobins result from post-translational changes in the hemoglobin molecule, and their levels correlate well with glycemic levels over the previous six to 10 weeks. Their use as an aid in monitoring diabetic control appears to be well established, but their value in predicting complications of diabetes and in diagnosing milder forms of diabetes is as yet unknown. Of the numerous methods available for the analysis of glycosylated hemoglobins, none has been evaluated extensively in a routine laboratory setting. However, liquid chromatography, isoelectric focusing, and radioimmunoassay techniques all give adequate results. For the purposes of monitoring long term diabetic control, assay of the fast hemoglobin fraction (AIa+b+c) appears adequate. However, for investigative purposes, when optimal sensitivity may be required, specific measurement of hemoglobin AIc is recommended.

Adult

The prolonged exercise test.

The response to a standardized exercise test was investigated in 12 volunteers and 13 patients with aches, cramps, and pains. In men, creatine kinase (CK) levels peaked (up to 1600 mU per milliliter) between 10 and 20 hours after exercise. High levels of blood lactate during exercise were related to the intensity of work and to high levels of CK after exercise. The patients could be divided into several groups: (1) those with no change in blood metabolites (psychogenic); (2) those with a disproportionate rise in CK (metabolic myopathies); (3) those with a disproportionate rise of lactate (mitochondrial abnormalities); and (4) in one patient with exercise-related pains, subnormal elevation of fatty acid levels. The correlation of changes in blood lactate, CK, and fatty acids may be useful, whereas an isolated measurement, even if outside the normal range, is often meaningless.

Adult

Increased serum creatine kinase after exercise: a sex-linked phenomenon.

The effect of 2 hours of exercise on the serum creatine kinase (CK) level was investigated in 11 men and 9 women. The mean increase of CK 24 hours after exercise was significantly greater in men. The relative lack of CK elevation in women may: (1) indicate that female muscle is less susceptible to damage by adverse factors; and (2) explain discrepancies in previous reports.

Creatine Kinase

Effects of beta-mercaptoethanol and chelating agents on the stability and activation of creatine kinase in serum.

We investigated the effects of sulfhydryl compounds on the stability of creatine kinase (CK) in unfrozen human serum and found that both beta-mercaptoethanol and N-acetylcysteine led to accelerated loss of the endogenous serum enzyme activity. This is in contrast to the results of others who have either studied the stability of exogenous enzyme added to human serum or studied endogenous enzyme in frozen serum. The addition of cation chelators to serum markedly improved the stability of the endogenous CK activity. The enhanced stability was independent of chelation of calcium, iron, manganese, copper, or zinc. In addition, cation chelators caused a 16% increase in the CK activity of fresh samples. This latter effect was independent of the activation of CK by BME and could be accounted for by chelation of calcium ions during the assay. The data suggest that addition of cation chelators prior to storage may be useful in enhancing the stability of CK in serum whereas sulfhydryl compounds should be added prior to assay rather than prior to storage.

Calcium

Cutaneous metastases from prostatic carcinoma.

A case of prostatic adenocarcinoma associated with extensive cutaneous metastases and malignant acanthosis nigricans is reported. Pertinent literature is reviewed. The pathogenesis of the possible mechanism of the development of cutaneous metastases in this as well as other related cases is discussed.

Acanthosis Nigricans

Fluorescent derivatives of prostaglandins and thromboxanes for liquid chromatography.

Fluorescent esters of the prostaglandins D2, E2, F2alpha, and 6-keto-F1alpha and of thromboxane B2 have been prepared using the reagent 4-bromomethyl-7-methoxycoumarin. All of these derivatives can be separated in a single run either by thin-layer or high-performance liquid chromatography (TLC or HPLC). As little as 20 ng of PGE2 can be detected after derivatization and HPLC analysis. Identification of thromboxane B2 produced by human platelets and of 6-keto-PG F1alpha produced by bovine aortic microsomes has been achieved with this method.

Animals