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Biomedical subjects

W C Johnson

Publications and source records attributed to W C Johnson.

At least 199 records · Page 11Linked to original sources
PubMed1977

Case of suspected connective tissue disease presenting as chronic edema or swelling of face, neck, and upper trunk.

An adequate biopsy that includes the subcutaneous tissue is very helpful in the evaluation of patients with suspected connective tissue disease. However, the histologic features must often be correlated with the clinical features and other laboratory tests for a definitive diagnosis. An objective histologic diagnosis can usually be made in scleroderma, lupus erythematosus panniculitis, amyloidosis, and angioedema, and in diseases such as lepromatous leprosy and mycosis fungoids (which are sometimes confused with connective tissue diseases). Correlation with clinical features and, sometimes, other laboratory tests is often required to establish a diagnosis of scleredema, dermatomyositis, myxedema, and lichen myxedematosus. The features in cheilitis granulomatosa usually are not specific, but a biopsy is helpful to rule out other diseases.

Adult↗
PubMed1976

Ultrasonic flow detection for localization of splenic and renal veins.

The selective splenorenal shunt is currently recommended as an alternative procedure to portocaval shunting. However, this operation is technically more difficult, particularly the localization of the renal vein in patients with thickened retroperitoneal tissues. The Doppler flow detector has helped us identify the splenic and renal veins, and we suggest the intraoperative use of this instrument in situations where difficulty is encountered.

Doppler Effect↗
PubMed1976

Efficacy of selective splanchnic arteriography and vasopressin perfusion in diagnosis and treatment of gastrointestinal hemorrhage.

Vasopressin infusion initially controlled 80 per cent of patients bleeding from portal hypertension, and 53 per cent did not rebleed after removal of the catheter. This figure is significantly greater than the 28 per cent of patients totally controlled by esophageal tamponade (p less than 0.075). Similar rates of success were achieved by vasopressin infusion for gastric, duodenal, and colonic bleeding sites. These results suggest that visceral arterial infusion of vasopressin is the method of choice for the short-term therapeutic management of massive gastrointestinal bleeding from portal hypertension. Vasopressin infusion also appears to be a valuable means of treating patients with massive gastrointestinal bleeding secondary to shallow gastric ulcers, gastritis, Mallory-Weiss tears, colonic bleeding and "poor risk" patients with deep gastric, marginal, or duodenal ulcers when conventional medical therapy has failed. The presence of a coagulation abnormality in patients with portal hypertension significantly reduced the complete control of bleeding to only 27 per cent ( p less than 0.010) and survival rate to 14 per cent (p less than 0.050). Visceral arterial perfusion proved to be an effective means of arresting hemorrhage, but the overall improvement in hospital mortality in this group of poor risk patients remains unproved.

Abdomen↗
PubMed1976

Secondary structure of nucleic acids in the folded chromosome from E. coli.

The circular dichroism of membrane-free folded chromosomes from E. coli was measured and analyzed. The spectrum can be explained as a simple linear combination of the individual spectra of E. coli RNA, and E. Coli DNA in the B form. No contribution from A form or C form DNA was detected. There was evidently some real variation in the ratio of the two nucleic acids from preparation to preparation, but the average value was 24% RNA and 76% DNA. No significant light scattering was observed and the analyses indicated no contribution to the circular dichroism from scattering artifacts. Apparently, combining DNA, RNA, and protein into membrane-free folded chromosomes does not change the secondary structure of the DNA or RNA from that found for the free nucleic acid in the same solvent system.

Chromosomes, Bacterial↗
PubMed1976

Lichenoid benign keratosis.

One hundred thirty-eight patients who presented with solitary cutaneous lesions appearing clinically as papules or plaques and histologically showing a lichenoid tissue reaction were studied. Many of the lesions occurred in sites not usually exposed to sunlight and histologically the lesions did not show significant atypical change in keratinocytes and many did not show evidence of solar elastosis in the superficial corium. Our study indicates that the lesions are benign keratoses showing a lichenoid tissue reaction or lichenoid benign keratoses.

Adolescent↗
PubMed1976

Portal hypertension changes following selective splenorenal shunt surgery. Evaluation by percutaneous transhepatic portal catheterization, venography, and cinefluorography.

Considerable diagnostic data can be gathered by selectively catheterizing the portal vein and the major tributaries of the splanchnic venous system to evaluate pressure and blood flow. Combined with cinefluorography, this is a superior method for demonstrating the anatomy and hemodynamics of portal hypertension as well as the effects of splenorenal shunt surgery. Thirty-one attempts with a 19 gauge trocar in 17 patients resulted in 28 successful portal entries and 24 successful selective catheterizations. Portal vein pressure, flow, and diameter were less after shunting.

Catheterization↗
PubMed1975

Male pattern alopecia a histopathologic and histochemical study.

Three hundred and forty-seven tissue specimens were studied from 23 patients with male pattern alopecia. Characteristic features of pattern alopecia included: the presence of miniature or vellus follicles; a marked enlargement of the sebaceous glands and arrectores pilorum muscles; the presence of connective tissue streamers beneath the vellus follicles; and the thinning of the dermis. A mild perivascular infiltrate of mononuclear cells and mild capillary dilatation was sometimes seen. An increased number of mast cells was often a prominent feature. Histochemical procedures were performed for glycogen, acid mucosaccharides, inorganic substances, and enzymes including alkaline phosphatase, acid phosphatase, beta glucuronidase, cholinesterase, aminopeptidase, oxidases and dehydrogenases. Histochemical studies did not reveal any significantly abnormal enzyme changes other than the altered vascular and nerve supply to the the miniature follicles.

Adult↗
PubMed1975

Two-dimensional polyacylamide gel electrophoresis of envelope proteins of Escherichia coli.

A method of separating envelope proteins by two-dimensional polyacrylamide gel electrophoresis is described. Escherichia coli envelopes (inner and outer membranes) were prepared by French pressing and washed by repeated centrifugation. Membrane proteins were solubilized with guanidine thiocyanate and were dialyzed against urea prior to two-dimensional electrophoretic analysis. The slab gel apparatus and conditions were similar to the technique developed by Metz and Bogorad (1974) for the separation of ribosomal proteins. This separation occurs in 8 M urea for the first dimension and in 0.2% sodium dodecyl sulfate for the second dimension. The technique separates about 70 different membrane proteins in a highly reproducible fashion according to both intrinsic charge and molecular weight. Some examples of alterations in the membrane protein pattern are demonstrated. These alterations are caused by a mutation affecting a sugar transport system and by growth in the presence of D-fucose, inducer of the transport system. A further example of membrane protein changes introduced by growth at the nonpermissive temperature of a temperature-sensitive cell division mutant is shown. Finally, it is demonstrated that the major outer membrane component of Escherichia coli K-12 contains more than four proteins of similar molecular weight.

Bacterial Proteins↗
PubMed1975

Tritiated thymidine uptake in pig skin. Comparison of in vivo and in vitro techniques.

Tritiated thymidine (3HT) was used in one of three ways to label deoxyribonucleic acid replication in epidermal cells of miniature swine: (1) the radioactive material was injected intracutaneously in vivo; (2) the radioactive material was injected intracutaneously into biopsy specimens and the specimens incubated in vitro in Eagle's medium, or (3) uninjected biopsy specimens were incubated in Eagle's medium with added 3HT. The first two methods yielded the same proportions of labeled cells with uniform distribution of labeled cells. The third method resulted in labeling of cells mainly at the periphery of the biopsy specimens. The advantages of the in vitro over the in vivo technique of injection of 3HT includes the fact that injecting a biopsy specimen avoids the problems of large amounts of radioactive waste disposal in animal studies or the legal and ethical problems of tracer studies in humans.

Animals↗
PubMed1975

Postoperative ventilatory performance: dependence upon surgical incision.

Sixty-one patients undergoing elective surgery were evaluated in regard to the degree of depression in FVC and FEV1 that occurred in the postoperative period. Following a thoracotomy a reduction of about 75 per cent occurred, after a long midline incision 68 per cent, after an upper midline or paramedian incision 61 per cent, after a subcostal incision 53 per cent and after a lower midline incision 38 per cent. This information may be useful in determining which patients are at an increased risk for postoperative respiratory insufficiency.

Abdomen↗
PubMed1975

A neglected modality in psychiatric treatment--the monoamine oxidase inhibitors.

The monoamine oxidase inhibitors are at present being used relatively infrequently in my opinion because of reports of severe and dangerous side effects such as toxic hepatocellular damage and hypertensive crises and also on account of several studies which have not given a very encouraging picture regarding the efficacy of this group of drugs. The purpose of this article is to demonstrate that this group of antidepressant drugs is very useful when the proper indications for their employment are observed and are relatively safe provided that appropriate precautions such as the avoidance of cheese and other foods high in tyramine content are taken by the patients being treated with these compounds. The history, pharmacology, side effects, and indications for their use are reviewed, and it is indicated that the MAO inhibitors are the therapeutic agents of choice in atypical depressions associated with anxiety, phobic and hysterical symptoms, and depressive illnesses (including endogenous depressions) which have failed to respond satisfactorily to tricyclic antidepressants. It is then demonstrated both from a review of the literature relating to these drugs and also from my own clinical experience that these compounds are very effective when used in the treatment of the psychiatric conditions for which they are indicated and are also relatively safe when the appropriate precautions are conscienciously observed.

Depression↗
PubMed1975

Flow and pressure characteristics of the portal system before and after splenorenal shunts.

The technique of percutaneous transhepatic portal vein cannulation provides a valuable means for determining portal pressure, direction of blood flow, and visualization of the entire portal system in the nonanesthetized patient. This technique, along with selective celiac arterial, superior mesenteric arterial, and renal venous catheterization, was used in the evaluation of a series of 17 splenorenal venous shunts [eight nonselective and nine selective (modified) distal splenorenal shunts]. As a result of these studies it is concluded that (1) prograde portal flow is maintained in the majority of patients following nonselective or selective (modified) distal splenorenal shunts; (2) bidirectional flow occurs in various branches of the portal system before and after splenorenal shunts; (3) a significant drop in portal pressure occurs following the establishment of either type of shunt; and (4) esophageal varices are decompressed by the trans-splenic route following either type of procedure used in this study.

Blood Pressure Determination↗