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Biomedical subjects

J J Williams

Publications and source records attributed to J J Williams.

At least 37 records · Page 2Linked to original sources
PubMed1986

CT of fibrous tissues and tumors with sonographic correlation.

Fibrous tissues and tumors may appear hyperdense relative to muscles and solid viscera on CT both before and after IV contrast injection. In addition, fibrous tissues generally have a homogeneously hypoechoic sonographic appearance. The diagnostic value of these criteria is illustrated in a group of 21 fibrous tissue abnormalities that includes retroperitoneal, mediastinal, and perigraft fibrosis, sclerosing pseudotumor of the orbit, generalized fibromatosis, desmoids, malignant fibrous histiocytoma, and normal tendons and ligaments. It is concluded that while hyperdensity on CT and echopenia on sonography are not pathognomonic of fibrous tissue, they occur with sufficient frequency that their presence raises the possibility of a fibrous lesion.

Connective Tissue↗
PubMed1986

Interaction of prostaglandins, activated complement, and granulocytes in clinical sepsis and hypotension.

Activated complement, thromboxane A2, prostacyclin, and activated granulocytes have been implicated in hemodynamic dysfunction after trauma, in sepsis, and in hypovolemic and septic shock. This study evaluated the interaction of plasma concentrations of complement components C3a and C5a, thromboxane B2 (TxB), prostaglandin 6-keto-F1 alpha (PGI), and granulocyte aggregation in clinical sepsis and hypotension. Forty-eight critically ill patients were followed clinically for as long as 10 days. Plasma C3a, C5a, TxB, and PGI were measured daily by the radioimmunoassay method. Granulocyte aggregation, the percentage of maximum aggregation of zymosan-activated plasma standard curves, was performed with patient plasma and normal human leukocytes. Patients were studied in four groups: group I, nonseptic, normotensive; group II, hypovolemic shock, group III, normotensive severe sepsis; and group IV, septic shock. Plasma from 12 normal adults was the control value. PGI, TxB, C3a, C5a, and granulocyte aggregation in patients were greater than that in the control subjects. Granulocyte aggregation was increased in groups III and IV versus groups I and II. C3a was increased in group IV versus groups II and III. C5a and TxB did not vary between groups. PGI was greatly increased in group IV compared with groups I through III. C3a and C5a decreased in nonsurvivors. PaO2/FiO2 ratios correlated directly with PGI and inversely with C3a and TxB/PGI. Plasma PGI and C3a are increased in septic shock. C3a and TxB/PGI imbalances are involved in hypovolemic and septic shock.

Adolescent↗
PubMed1986

Microbial filtrates activate granulocytes without complement or prostaglandins.

UNLABELLED: Cardiorespiratory dysfunction in sepsis may be mediated by circulating complement, activated leukocytes, prostaglandins, or by a direct effect of endotoxin. The purposes of this study were to determine if pathogenic microbes produce these substances and to evaluate the direct effects of substances released by micro-organisms on granulocyte aggregation (GA). Escherichia coli, (E. coli), Aeromonas hydrophila (Aeromonas h.), Staphylococcus aureus (S. aureus), and Candida albicans, (Candida a.) were incubated in broth to a concentration of 10(9)/ml. Broth was filtered and analyzed by radioimmunoassay for complement components C3a and C5a, thromboxane B2 (TxB), and prostaglandin 6-keto-F1 alpha (PGI) and by the limulus amebocyte lysate test (LAL) for endotoxin. GA, % of maximum zymosan activated aggregation (% max. T), was performed with broth, microbial filtrates, and endotoxin or normal purified human leukocytes in HBSS. Organisms were incubated in broth (B), broth + 0.0135 mg/ml arachidonic acid (BA), and broth + arachidonic acid + indomethacin (BAI). Broth alone was the control (C). RESULTS: C3a, C5a, TxB, and PGI were not detectable in C broth or in any microbian filtrate. LAL was positive in all filtrates, but negative in C broth. GA responses were significantly greater in E. coli (56 +/- 5% max T) and Aeromonas h. (57% +/- 8% max T) compared to S. aureus (10 +/- 5% max T), Candida a. (14 +/- 8% max T) and C broth (1 +/- 1% max T). GA with purified E. coli endotoxin at concentrations measured in the filtrates was not related to the GA responses the original filtrates.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteria↗
PubMed1985

Impact of renal donation. Long-term clinical and biochemical follow-up of living donors in a single center.

Forty-six renal donors who responded to a questionnaire and two additional donors with nephrotic syndrome and renal insufficiency were studied. The mean age was 46 +/- 2.0 years (mean +/- SE). Duration of follow-up was 6 +/- 0.5 years. Serum creatinine levels increased from 1.0 +/- 0.03 mg/dl before donation to 1.2 +/- 0.04 mg/dl at follow-up. The incidence of proteinuria (more than 150 mg over 24 hours) was 39 percent. The serum creatinine level was 1.0 +/- 0.08 mg/dl and 1.2 +/- 0.06 mg/dl in the proteinuric and nonproteinuric groups, respectively. The incidence of hypertension was 31 percent with a serum creatinine level of 1.1 +/- 0.11 mg/dl and 1.2 +/- 0.07 mg/dl in the hypertensive and normotensive groups, respectively. One patient with nephrotic syndrome had proliferative glomerulonephritis. It is concluded that renal donation is associated with a minimal but statistically significant increment in serum creatinine levels. The incidence of mild hypertension and proteinuria is increased, but impact on renal function is minimal as assessed by serum creatinine determination.

Adolescent↗
PubMed1985

Hypoxic pulmonary vasoconstriction is not potentiated by repeated intermittent hypoxia in closed chest dogs.

Hypoxic pulmonary vasoconstrictor (HPV) responses were measured with repeated intermittent hypoxic challenges in eight non-traumatized closed chest dogs anesthetized with pentobarbital. The right lung was ventilated continuously with 100% O2 while the left lung was either ventilated with 100% O2 (control) or ventilated with a gas mixture containing 3-4% O2 (hypoxia). Mean per cent left lung blood flow for all four normoxic periods was 43.1 +/- 1.5% (mean +/- SE) of the total blood flow by the SF6 excretion method and 40.8 +/- 1.1% by the differential CO2 excretion method, corrected for the Haldane effect. With hypoxic ventilation, flow diversion from the hypoxic lung was maximal with the first exposure and did not change subsequently with a total of four alternating exposures to normoxia and hypoxia. Flow diversion during hypoxia was approximately 50.5 +/- 2.4% by the SF6 method and 50.3 +/- 3.5% by the VCO2 method. This result contrasts with the increasing flow diversion response with intermittant hypoxic exposure that has been reported in animals exposed first to thoracotomy and surgical dissection. It is concluded that in the absence of surgical trauma the initial response to hypoxia is maximal and is not potentiated by repeated hypoxic stimulation.

Anesthesia, Intravenous↗
PubMed1984

A randomized double-blind study of acetohydroxamic acid in struvite nephrolithiasis.

We studied the effects of the bacterial urease inhibitor acetohydroxamic acid on the growth of struvite stones in the urinary tract. Eighteen patients who received acetohydroxamic acid (15 mg per kilogram of body weight per day, in divided oral doses) for a mean of 15.8 months were compared in a randomized double-blind study with 19 patients who received placebo for a mean of 19.6 months. Seven patients given placebo reached a pre-determined end point: a 100 per cent increase in the two-dimensional surface area of their stones. No patient who received acetohydroxamic acid had a doubling of stone size (P less than 0.01). Nine patients receiving the drug and one patient receiving placebo required a decrease in dosage or cessation of treatment because of adverse effects (P less than 0.01). Episodes of tremulousness (n = 5, P less than 0.05), which reversed with a decrease in drug dose, and phlebothrombosis (n = 3, P not significant) were limited to the group given acetohydroxamic acid. We conclude that acetohydroxamic acid effectively inhibits the growth of struvite stones in the short term in patients infected with urea-splitting bacteria, but the prevalence of adverse reactions appears to be high and the toxicity and effectiveness of long-term therapy for struvite nephrolithiasis remain to be defined.

Adult↗
PubMed1984

ED50 of alfentanil for induction of anesthesia in unpremedicated young adults.

This study determined the ED50 and ED90 of alfentanil for unconsciousness and anesthesia. A bolus of alfentanil was given to 28 healthy unpremedicated adults undergoing gynecologic or orthopedic procedures in one of four dosages: 100, 150, 200, or 250 micrograms/kg. Three indicators of induction were assessed 90 s later: eyelid reflex, response to verbal commands to breathe, and response to placement of a nasopharyngeal airway. Succinylcholine, given at 90 s, was followed by tracheal intubation 1 min later. From probit analysis, the ED50 and ED90 for loss of voice response were 92 and 111 micrograms/kg, respectively, and for loss of nasopharyngeal airway response, 111 and 169 micrograms/kg. A high incidence of chest wall rigidity (75%) and movements of the limbs (54%) or eyes (25%) was seen. There were statistically significant increases of the heart rate prior to stimulation and of both the heart rate (21% rise) and systolic blood pressure (10% rise) from control to the peak value following intubation. Differences between alfentanil doses were not significant. Naloxone was required in 36% of patients for end-tidal PCO2 greater than 48 mmHg at emergence from anesthesia; no patient required additional naloxone. Nausea or vomiting occurred in 39% of all subjects. Two patients recalled placement of the nasopharyngeal airway. We conclude that alfentanil is an anesthetic, and its ED50 (analogous to MAC of inhalational agents) is 111 micrograms/kg. The blood pressure and heart rate responses to laryngoscopy and intubation were modest after doses that allowed for extubation as early as 51 min after induction.

Adjuvants, Anesthesia↗
PubMed1984

Time course and responses of sustained hypoxic pulmonary vasoconstriction in the dog.

The stability of the pulmonary blood pressure and flow response to alveolar hypoxia (hypoxic pulmonary vasoconstriction or HPV) was studied in six pentobarbital anesthetized, mechanically ventilated open-chested dogs. Aortic and left pulmonary artery blood flows; systemic and pulmonary arterial, central venous, left atrial, and airway pressures; hemoglobin; arterial and mixed venous blood gases were measured. The right lung was ventilated continuously with 100% oxygen, while the left lung was ventilated alternately with 100% O2 ( prehypoxia control phase), an hypoxic gas mixture containing 4% O2, 3% CO2, balance N2 for 4 h, or 100% O2 (post-hypoxia control phase). Hypoxic ventilation of the left lung resulted in an immediate and sustained decrease in left lung blood flow (QL%) from 39.0 +/- 1.8% (mean +/- SE) to 9.9 +/- 3.6% at 15 min of hypoxic ventilation. QL% remained decreased and did not vary significantly during the 4 h of hypoxia. Venous admixture correspondingly was increased and PaO2 decreased by hypoxic ventilation and did not vary significantly during the 4 h of hypoxia. All variables returned to control levels upon reestablishing ventilation with 100% O2. While the maximal reduction in QL% with left lung hypoxic ventilation was identical to that observed during atelectasis previously in our laboratory, the time course of the response was different. The response to hypoxia was maximal by 15 min, however, QL% decreased more slowly during atelectasis, where the maximal reduction was observed by 60 min. The present study therefore demonstrated that hypoxic ventilation of the left lung yielded an immediate and sustained decrease in left lung blood flow for 4 h. The stability of the HPV response probably was accounted for by the lack of such confounding factors as respiratory alkalosis, severe systemic hypoxemia, and increased cardiac output.

Analysis of Variance↗
PubMed1984

CT of the hyperdense renal cyst: sonographic correlation.

The computed tomographic (CT) appearances of 19 hyperdense renal cysts in nine patients are reported. Sixteen of these cysts were found over a period of only 1 year with state-of-the-art CT equipment. Hyperdense renal cysts are probably more common than suggested by case reports. Their rate of detection can be expected to increase with the wider availability of fast CT scanners using thin collimation. A CT diagnosis of benign hyperdense renal cyst can be made if a lesion meets all of the following criteria: (1) smoothly outlined imperceptible wall with sharp demarcation from the kidney; (2) before intravenous contrast injection, homogeneous internal content with CT numbers 40%-240% higher (70%-240% higher for lesions 10 mm or more in diameter) than renal parenchyma; and (3) after intravenous contrast injection, persistent internal homogeneity and insignificant enhancement (less than 6%) relative to normal renal cortex. For masses exceeding 15 mm in diameter, sonography can be a valuable confirmatory test.

Aged↗
PubMed1984

The effect of dietary protein on cystine excretion in patients with cystinuria.

Seven patients with homozygous cystinuria were studied on a metabolic ward to determine the effect of dietary manipulation on urinary cystine excretion. Isocaloric diets were calculated based on body weight and activity. Balance studies were performed for 5 days on a low protein diet (9.4 +/- 1.0% total calories) with equal amounts of animal and plant protein sources and an additional 5 days on a high protein (27 +/- 3.0% of total calories) with 70% animal protein. A significant (p less than 0.01) decrease in the excretion of 1/2-cystine, histidine, 3-methylhistidine, 1-methylhistidine, lysine, and ornithine plus arginine occurred on the low protein diet. The mean excretion of 1/2-cystine on the high protein diet was 6.13 +/- 1.48 mMoles per 24 hours which decreased to 4.89 +/- 1.06 mMoles per 24 hours on the low protein diet (p less than 0.001). Thirty seven percent of urine collections during the study were less than 2 liters/24 hours despite the fact that patients were encouraged to drink enough fluid to make 3 liters of urine/24 hours. For patients whose customary diet is high in animal protein, a more vegetarian diet may significantly reduce urinary cystine excretion. Cystine excretion in patients with cystinuria may be significantly different from day to day if animal protein consumption is variable.

Adolescent↗
PubMed1983

Partial dissolution of struvite calculus with oral acetohydroxamic acid.

Most staghorn calculi occur in patients who have chronic urinary tract infections with urea-splitting organisms. Acetohydroxamic acid, an inhibitor of the bacterial urease enzyme, is currently undergoing clinical trials to determine whether or not it can prevent stone growth in patients at risk. We report on a patient whose stones grew while she was taking placebo and then decreased in size when she took the active drug.

Administration, Oral↗
PubMed1982

Hyperoxia inhibits stimulated superoxide release by rat alveolar macrophages.

Factors responsible for the loss of respiratory burst capacity (stimulated extracellular O2-. release) of alveolar macrophages (AM) exposed to prolonged hyperoxia were assessed. Specific pathogen-free rats were exposed to 1 ATA O2 for 24-72 h, and lungs of survivors lavaged. Release of O2-. by cells after addition of concanavalin A, which stimulated AM but not polymorphonuclear leukocytes (PMN), or digitonin, which stimulated both cell types, was measured using cytochrome c reduction +/- superoxide dismutase. O2-. release by AM declined 47.2% (P less than 0.05) after 24 h of hyperoxia and 100% after 60 h. Percent PMN in the lavage was less than 3% at 0-36 h but increased to 16% at 48 h and to 44% at 72 h. Although addition of PMN to AM in vitro caused inhibition of AM O2-. release, the percent PMN required for inhibition was not reached in vivo until after a significant decline in AM O2-.-releasing capacity had already occurred. Cell-free lavage fluid from either control or hyperoxic rats did not affect AM O2-. release. AM in culture for 24 h in hyperoxia lost 76.7% (P less than 0.005) of O2-.-releasing capacity vs. cells incubated in 20% O2, although dye exclusion was unaffected. The results indicate that the major cause of loss of AM O2-. release by hyperoxia is a direct effect of O2 on the cells.

Animals↗
PubMed1980

Achalasia and microcephaly.

The authors report the combination of achalasia, microcephaly, and mental retardation in three surviving sisters and similar manifestations in a brother who died after recurrent vomiting and respiratory infections. The achalasia in the females was relieved with an operation. There was no demonstrable chromosomal abnormality. In this family achalasia, microcephaly, and mental retardation occurred together as an apparent autosomal recessive syndrome.

Adult↗
PubMed1980

Genetically determined asynapsis, spermatogenic degeneration, and infertility in men.

We report a family in which azoospermia and infertility affected two sibs whose parents were first cousins once removed. Meiotic cells of the proband, who had the chromosomal complement of a normal male (46,XY), exhibited asynapsis, defective synaptonemal complex (SC) formation, chiasma failure, and degeneration of prophase spermatocytes with asynapsis. Based on these observations, we suggest that the meiotic abnormalities and infertility in this family comprise a trait with an autosomal recessive mode of inheritance. Review of published cases of infertile men with normal chromosomal complements and disturbed meiosis suggests that genetically determined asynapsis and desynapsis similar to that established in plant and insect species also occur in humans. In humans, asynapsis appears to be inherited as an autosomal recessive. The mode of inheritance of desynapsis is not clear; X-linked recessive or autosomal dominant has been suggested in one family. Studies by us and by others reported in the literature suggest that the mode of action of genes that affect synapsis and cause a reduction in the numbers of visible chiasmata at diakinesis is dissimilar to that of the action of genes that cause defective meiotic recombination, defective repair of induced damage to DNA in somatic cells, and chromosome instability.

Adult↗
PubMed1979

Hemangioendothelial sarcoma of penis.

Hemangioendothelial sarcoma of the penis in a 44-year-old man was treated by preoperative radiation, penectomy, and chemotherapy. The patient was free of evident disease 2 years later. Electronmicroscopy showed differentiated vascular structures at the periphery of the lesion and anaplastic cells throughout the remainder of the tumor.

Adult↗