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Biomedical subjects

W D Williams

Publications and source records attributed to W D Williams.

At least 19 recordsLinked to original sources
PubMed2001

Salinization: unplumbed salt in a parched landscape.

The global hydrological and salt cycles are described, as are the ways in which human activities have led to their disturbance. One effect of this disturbance is the unnatural increase in the salinity of many inland waters (secondary salinization). The geographical extent of secondary salinization is outlined, together with its effects on various types of inland waters, such as salt lakes, freshwater lakes and wetlands, and rivers and streams. The likely impact on salinization of global climate change is summarized.

Disasters↗
PubMed1993

Multisystem damage associated with tricorporal priapism in sickle cell disease.

PURPOSE: Priapism is an uncommon but debilitating complication of sickle cell disease (SCD). Recent observations among adult males regarding the abysmal failure of medical and surgical therapy encouraged us to review our 25-year experience identifying the prognostic features that might determine outcome. PATIENTS AND METHODS: As part of a prospective 25-year longitudinal demographic and clinical cohort study, a subset of 38 (8.2%) patients with priapism were identified among a cohort of 461 men with SCD. The patients with priapism were compared with the nonaffected men with respect to severity of disease expression, hematologic status, beta s globin gene haplotype, and the incidence of sickle-related major organ failure. The influence of the treatment modalities on outcome was also evaluated. RESULTS: Priapism occurred as a single episode in 24 patients, and in 14 as temporally clustered repeat episodes. Eighty-seven percent of those with priapism had sickle cell anemia (SS), an increased risk as compared with other variants of SCD (p = < 0.05). There were two distinct age-related patterns of disease expression. Eight patients were prepubertal; they experienced shorter episodes, involvement of the corpora cavernosa only, few recurrent episodes, and a good prognosis for future erectile function. Non-surgical therapy in children was associated with excellent results. In contrast, the 29 postpubertal adults often had involvement of the corpora cavernosa and corpus spongiosa (tricorporal disease) and half had prolonged episodes that lasted longer than 8 days. One pubescent patient had repeated episodes and became impotent. Prolonged or repeated episodes eventuated in impotence in 56%. Surgical intervention was not beneficial. Sickle cell-related organ failure such as stroke, chronic restrictive lung disease, chronic renal failure, and nonhealing leg ulcers was observed more frequently in men who had priapism. Death occurred in nine adult patients (25%) within 5 years of the first episode of priapism. CONCLUSION: Priapism in adult males identifies those at high risk for other sickle cell-related organ failure syndromes and, as such, is another complication indicative of severe disease. The dismal prognosis in SS adults requires better understanding of the precise pathophysiology of low-flow tricorporal priapism. Clarification of the mechanisms inducing the priapic state should lead to specific therapeutic maneuvers and an improved prognosis for this disabling condition.

Adolescent↗
PubMed1992

High-level expression of recombinant human tPA in cultivated canine endothelial cells under varying conditions of retroviral gene transfer.

Successful genetic transduction of endothelial cells (EC) provides a theoretic means of increasing luminal secretion of tissue-type plasminogen activator (tPA) and lessening arterial and venous thrombotic processes. To identify the duration and number of retroviral exposures for an optimal tPA expression, enzymatically derived adult canine jugular venous EC were subjected to different exposure regimens using an amphotropic murine retroviral vector, MFG, containing the human tPA gene. Human tPA antigen secretion and its functional activity were determined at 2 days (subconfluent cells) and 14 days (confluent cells) after retroviral exposure. High-level secretion of human tPA was detected among transduced EC in all experimental groups. No secretion of human tPA occurred in control EC exposed to media alone. At 2 days after transduction, no significant differences in tPA secretion rates occurred among the different exposure regimens. At 14 days, the 12-hour X two-exposure group exhibited higher tPA secretion rates than all other exposure regimens (analysis of variance, p < 0.05). All exposure groups at 14 days exhibited significantly higher tPA secretion compared with those at 2 days (analysis of variance, p < 0.05). The presence of retroviral sequences in the genome of transduced EC was confirmed by Southern blot analysis. At 14 days, increased EC numbers were observed in vector-exposed wells compared with controls. Human tPA functional activity paralleled tPA antigen secretion. Genetically modified canine EC are capable of high levels of constitutive expression of human tPA after relatively short exposures to a retroviral vector containing the reporter gene. Increased cell number of tPA-transduced EC in culture suggests that tPA also may have other biologically important effects. These results support the efficacy of MFG-tPA gene transfer as a means of genetically modifying EC fibrinolytic activity and establishes the potential of this technology in vivo.

Animals↗
PubMed1992

Origin and impact of color on consumer preference for food.

There are great differences among species in the way pigment is deposited on the skin or in the egg yolk. Xanthophyll-type compounds produce the color. Consumers have associated a yellow color with a normal state of health. Many consumers insist on the color and indicate that increased cost is not much of a deterrent. At present, increasing the pigmenting properties of a poultry feed increases costs from $5 to $15/ton. Pigmentation is more costly in the fish industry and may increase the cost of the diet up to or over $100/ton, especially in the final 20% of the feed consumed before processing. The pigmentation should be consistent and uniform in both species. A history of high-pigment broilers is presented. High-pigment broilers lend themselves to effective television advertising.

Animals↗
PubMed1989

Nonblack patients with sickle cell disease have African beta S gene cluster haplotypes.

Of 18 nonblack patients with sickle cell disease, 14 had sickle cell anemia, 2 had hemoglobin SC disease, and 2 had hemoglobin S-beta o-thalassemia. The beta s gene cluster haplotypes that were determined in 7 patients were of African origin and were identified as Central African Republic, Central African Republic minor II, Benin, and Senegal. The haplotype Central African Republic minor II was present on the beta o-thalassemia chromosome in 2 patients. None of 10 patients whose alpha-gene status was determined had alpha-thalassemia-2. These data strongly support the concept that the beta s gene on chromosome 11 of these individuals is of African origin and that the alpha-gene locus on chromosome 16 is of white or native American origin. The clinical severity of the disease in these nonblack patients is appropriate to their haplotype without alpha-thalassemia-2 and is comparable with that of black patients. All persons with congenital hemolytic anemia should be examined for the presence of sickle cell disease regardless of physical appearance or ethnic background.

Adult↗
PubMed1984

Peritoneal keratin globules in uterine adenosquamous carcinoma.

We have described a previously unreported lesion--peritoneal keratin globules in uterine adenosquamous carcinoma. We postulate that the keratin globules are derived from sloughed uterine adenosquamous carcinoma which gains access to the peritoneum through retrograde dissemination via the fallopian tubes, and we suggest that the finding of these globules does not alter the prognosis and staging of the primary carcinoma.

Adenocarcinoma↗
PubMed1984

The lysine requirement of the growing boar versus barrow.

Five experiments were conducted to determine if boars and barrows differ in the level of dietary lysine required to maximize growth rate, efficiency of feed utilization, carcass leanness and N retention. In Exp. 1, 48 boars and 48 barrows were fed fortified corn-soybean meal diets calculated to contain 14 (grower) and 12% protein (finisher) and supplemented with 0, .15 or .30% lysine from 27 to 105 kg body weight. The basal diets analyzed .60 and .47% lysine, respectively. Linear improvements in feed/gain (P less than .01), backfat thickness (P less than .10), longissimus muscle area (P less than .01), and ham-loin (P less than .05) and lean cuts percentage (P less than .1) were observed in boars as dietary lysine increased. In barrows, however, growth rate, feed:gain ratio and carcass characteristics (except longissimus muscle area) were not significantly affected by dietary lysine level. In Exp. 2, 18 boars and 18 barrows initially averaging 64 kg body weight were fed a 12% protein diet (.47% lysine) supplemented with 0, .15 or .30% lysine. Linear (P less than .05) increases in N retention occurred in boars, but not barrows, as dietary lysine was increased. In Exp. 3 and 4, 140 boars (34 to 103 kg) were fed a 14-12% protein sequence (analyzed .61 and .48% lysine) supplemented with 0, .1, .2, .3 or .4% lysine. In Exp. 5, 60 boars (23 to 103 kg) were fed a 16-14% protein sequence (analyzed .83 and .68% lysine) supplemented with 0, .075, .15 or .225% lysine.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed1984

A malignant neoplasm with features of both squamous cell carcinoma and malignant melanoma.

A case of a malignant neoplasm with features suggestive of both malignant melanoma and squamous cell carcinoma is reported. The neoplastic cells were positive for both S-100 protein and keratin when stained by the indirect peroxidase-antiperoxidase method. The literature on other instances of bi- or multidirectional differentiation of neoplastic cells is reviewed. The significance of these findings for terminology of neoplasms is discussed.

Aged↗
PubMed1983

Pre-treatment and post-treatment evaluation of prostatic adenocarcinoma for prostatic specific acid phosphatase and prostatic specific antigen by immunohistochemistry.

Prostatic specific acid phosphatase and prostatic specific antigen have been used as specific markers of prostatic adenocarcinoma in immunohistochemical studies, particularly when seeking the primary site of a poorly differentiated metastasis. We herein evaluate the effect of therapy on the persistence of these markers in surgically obtained tissues. Prostatic biopsies from 30 patients with adenocarcinoma of the prostate gland before and after treatment with orchiectomy alone, diethylstilbestrol, external beam radiation or combined radiation and diethylstilbestrol were studied for prostatic specific acid phosphatase and prostatic specific antigen using the indirect immunoperoxidase technique. The interval between biopsies ranged from 3 to 72 months, with an average of 28 months. All pre-treatment biopsies stained positively for prostatic specific acid phosphatase and prostatic specific antigen. Staining for prostatic specific antigen and prostatic specific acid phosphatase was seen easily in 29 of 30 post-treatment biopsies, while in 1 case infiltrating anaplastic cells surrounded by stroma showed staining for these antigens in an extremely small percentage of cells, which were overlooked easily unless examined carefully. In view of this small number of positively staining cells this case was designated as equivocal. While some cases demonstrated less intense staining in post-treatment biopsies compared to pre-treatment, this finding was by no means constant. With these primary antisera a higher percentage of cytologically malignant cells stained positively for prostatic specific acid phosphatase than for prostatic specific antigen in adjacent tissue sections in some cases. Prostatic specific acid phosphatase and prostatic specific antigen appear to be sensitive and persistent markers of prostatic adenocarcinoma despite morphologic changes accompanying various therapies.

Acid Phosphatase↗
PubMed1978

The effects of insulin glucose administration in fulminant hepatic failure.

Insulin glucose therapy can correct hyponatraemia and renal sodium retention in burns, sepsis and circulatory failure. A case of fulminant hepatic failure (F.H.F.) is described in which the same effect was observed. Insulin was thought to have corrected abnormal cell membrane permeability. The actions of insulin are discussed in relation to its possible role in the management of F.H.F.

Female↗
PubMed1977

Ethanol--its nephrotoxic effect in the rat.

The nephrotoxic effect of ethanol feeding on renal structure and function was evaluated in rats and compared to that in dextrose-fed isocaloric control animals. Alcohol-fed animals had larger kidneys than their controls. Despite this increase in renal mass, the alcohol-fed animals had a 50% reduction in creatinine clearance and a 67% reduction in osmolar clearance compared to their controls. When specific renal constituents were compared, the alcohol-fed animals were found to have twice the renal protein and a 50% increase in renal lipid. Despite these marked structural and functional differences, the light microscopic appearance of the kidneys of the two groups did not appear significantly different. In contrast, the electron microscopic differences were substantial. The renal epithelial cells, particularly of the distal tubules and Henle's loops, were found to show varying degrees of cellular injury and were observed to be sloughing into the lumens. These electron microscopic observations are similar to those obtained in tubular necrosis due to a variety of nephrotoxic agents. We propose, therefore, that chronic alcohol feeding of rats produces significant renal dysfunction and abnormalities of structure such that ethanol should be considered a true nephrotoxin.

Acute Kidney Injury↗