Publications by authors named "Chandler W"

An artificial immune complex consisting of IgG covalently bound to polyacrylic acid (PAIGP) was prepared and investigated for its influence on a number of immunological reactions attributed to natural immune complexes. PAIGP consumed complement in a fast reaction. Complement consumption was complete after 10 min of incubation of guinea-pig serum with PAIGP.

View Article and Find Full Text PDF

Junge and McLaughlin (1987) derived an expression for the apparent diffusion constant of protons in the presence of both mobile and immobile buffers. Their derivation applies only to cases in which the values of pH are considerably greater than the largest pK of the individual buffers, a condition that is not expected to hold in skeletal muscle or many other cell types. Here we show that, if the pH gradients are small, the same expression for the apparent diffusion constant of protons can be derived without such constraints on the values of the pK's.

View Article and Find Full Text PDF

To evaluate possible hormonal regulators of the diurnal rhythm in fibrinolytic activity, we measured tissue plasminogen activator (t-PA) activity, plasminogen activator inhibitor activity (PAI-1), t-PA antigen, insulin, cortisol, and catecholamines in 6 healthy males (age 34 +/- 5) every 2 hours for 24 hours. Fibrinolysis was characterized by a peak in PAI-1 activity and a trough in t-PA activity at 0600 h. PAI-1 activity increased 92% and t-PA activity decreased 56% between 2400 h and 0600 h.

View Article and Find Full Text PDF

The effects of the hypothalamic hormones, thyrotropin-releasing hormone (TRH), and somatostatin (SRIH), and of phorbol 12-myristate 13-acetate (PMA) on PRL and GH secretion and messenger RNA (mRNA) levels were analyzed in 10 GH and/or PRL producing adenomas after culturing the tumor cells in the presence of these secretagogues for 7 days. The expression of chromogranin A and B mRNAs was also examined. All four of the clinically diagnosed GH adenomas expressed or secreted both GH and PRL while four of six clinically diagnosed prolactinomas produced or secreted both PRL and GH.

View Article and Find Full Text PDF

In the course of a study on glioblastoma tissue and cultured cell lines, a glitter drop technique for random sampling was introduced (1). Here, we report the initial description of the details of this procedure and its application to cell counts from explant slides and to determining bromodeoxyuridine (BUdR) labeling indices (LI) in tissues. The method is without bias, easy to perform and takes only a short time.

View Article and Find Full Text PDF

The objective of this study was to determine whether nuclear parameters were associated with prognosis in glioblastoma multiforme. DNA indices, cell cycle parameters, and nuclear population densities were compared with patient survival. Selection criteria included the pathologic diagnosis of a cerebral glioblastoma multiforme, absence of therapy before surgery, and adequate tissue to measure each nuclear parameter studied.

View Article and Find Full Text PDF

CT demonstration of cavernous sinus fat deposits has been described as abnormal and potentially a specific sign of Cushing disease. CT scans of 100 patients without biochemical or clinical evidence of Cushing disease and of 10 patients with Cushing disease were studied retrospectively. Twenty-seven percent of the non-Cushing patients demonstrated fat in one or both cavernous sinuses.

View Article and Find Full Text PDF

Both domperidone (DOMP) and metoclopramide (MCP) are D2 receptor antagonists, MCP being a central and peripheral dopamine antagonist, whereas DOMP is exclusively a peripheral antagonist. MCP, but not DOMP, has been shown to stimulate aldosterone production. To elucidate whether aldosterone stimulation by dopamine antagonism is centrally mediated, we injected DOMP (28 micrograms/kg body wt) via a cannula into the third ventricle in Sprague-Dawley rats.

View Article and Find Full Text PDF

Two new Ca indicators, purpurate-3,3'diacetic acid (PDAA) and 1,1'-dimethylpurpurate-3,3'diacetic acid (DMPDAA), were synthesized and used to measure Ca transients in frog cut muscle fibers. These indicators are analogues of the purpurate components of murexide and tetramethylmurexide, in which two acetate groups have been incorporated into each molecule to render it membrane impermeant. The apparent dissociation constant for Ca is 0.

View Article and Find Full Text PDF

We have standardized the measurement of plasminogen activator inhibitor type 1 (PAI-1) activity in plasma. One-chain tissue-type plasminogen activator (t-PA; EC 3.4.

View Article and Find Full Text PDF

Antipyrylazo III was introduced into frog cut twitch fibers (17-19 degrees C) by diffusion. After action potential stimulation, the change in indicator absorbance could be resolved into two components that had different time courses and wavelength dependences. The first component was early and transient and due to an increase in myoplasmic free [Ca] (Maylie, J.

View Article and Find Full Text PDF

Current studies show a more than 50-fold variation in the estimated level of tissue-type plasminogen activator (t-PA) activity in normal resting blood samples that result from major differences in the methods used to sample, preserve, and assay t-PA activity in blood. In this study we developed optimized methods for stabilizing and measuring t-PA activity in plasma by using a coupled plasminogen-chromogenic substrate (amidolytic) assay. To maximize the recovery of t-PA activity, blood should be acidified within 60 seconds after being drawn by adding 2 parts whole blood to 1 part 0.

View Article and Find Full Text PDF

Acidophilic pituitary adenomas commonly produce growth hormone (GH) or prolactin (PRL), according to studies employing immunohistochemical and ultrastructural methods. To examine this question, in situ hybridization with oligonucleotide probes was done on routinely processed tissues received in the pathology laboratory to analyze for the presence of GH and PRL messenger RNA (mRNA) in 4 normal pituitaries, 10 prolactinomas, and 16 GH-secreting adenomas. Most acidophilic cells in normal pituitaries expressed either GH or PRL hormone and the respective mRNAs, but GH mRNA and PRL hormone were also detected in some of the same cells.

View Article and Find Full Text PDF

Color Doppler flow ultrasound (US) was used to locate and image intracerebral arteriovenous malformations (AVMs). US was deemed useful in eight of 12 patients who underwent AVM resection. Blood flow in the eight lesions was clearly evident, and major feeding arteries and draining veins, such as the superior sagittal sinus, were identified.

View Article and Find Full Text PDF

Previous studies have shown that overall fibrinolytic activity in blood follows a diurnal rhythm with a peak in the morning and a trough in the evening. The purpose of this study was to determine which fibrinolytic factor(s) was responsible for this diurnal rhythm. Resting and postvenous occlusion tissue-type plasminogen activator (t-PA) activity, resting t-PA antigen, and resting plasminogen activator inhibitor 1 (PAI-1) activity were measured in the morning and evening in 33 healthy men (mean age, 31 years) and in 15 patients (mean age, 57 years) with previous myocardial infarction or unstable angina.

View Article and Find Full Text PDF

A primate toxicity study was performed to test the hypothesis that BUdR does not increase the likelihood of unilateral or bilateral central nervous system damage secondary to radiation therapy. BUdR, a halogenated pyrimidine analog is incorporated into DNA of dividing cells and sensitizes them to radiation. It is best given unilaterally, intra-arterially by continuous infusion because of its regional advantage (Rd) estimated to be between 11 and 16.

View Article and Find Full Text PDF

Ten patients with previously untreated acromegaly and invasive pituitary macroadenomas were treated with the long-acting somatostatin analog SMS 201-995 (Sandoz) for 3-30 weeks before transsphenoidal or subfrontal pituitary adenomectomy. Preoperatively, treatment with SMS 201-995 reduced mean 24-h plasma GH concentrations from 8.5-66.

View Article and Find Full Text PDF

Bromodeoxyuridine (BUdR), a nonhypoxic radiosensitizing drug, is a halogenated pyrimidine analog that is incorporated into the deoxyribonucleic acid of dividing cells in a competitive process with thymidine; BUdR also sensitizes these cells to radiation therapy. Neurons and glial cells have a very low mitotic rate. They will not incorporate BUdR and will not be sensitized.

View Article and Find Full Text PDF

Using homogenates of autopsy tissue, we compared three widely available techniques for separating amylase isoenzymes: wheat-germ inhibition (WI), and electrophoresis on cellulose acetate (CA) or agarose (AG). WI separated amylase into two isoforms, CA into seven (three pancreatic and four salivary), and AG into nine (five pancreatic and four salivary). CA and WI had similar isoamylase detection limits (8-10 U/L) and similar imprecision in measuring percent S-type vs P-type isoamylase (within-run SD 1-2%), and they demonstrated a linear response to added S or P isoamylase.

View Article and Find Full Text PDF

We quantified total amylase and its isoenzymes in 22 different human tissues obtained at autopsy. Isoenzymes were separated by use of wheat-germ inhibition (WI) and electrophoresis on cellulose acetate (CA) and agarose (AG). Mean (+/- SD) total activity was highest in salivary glands (parotid 1710 +/- 897 U/g, submandibular 605 +/- 354 U/g), and pancreas (258 +/- 137 U/g).

View Article and Find Full Text PDF

Dual lumen silicon rubber right atrial catheters were implanted into the jugular of 8 rabbits and tunneled subcutaneously to exit sites between the ears. Using a miniaturized tubing-pump system, blood flow rates of 25 ml/min could be achieved for up to 3 1/2 hours without sign of hemolysis in an extracorporeal blood circuit. Seven catheters functioned an average of 75 +/- SE 19 days (range 24-117).

View Article and Find Full Text PDF

We compared two assays for estimating the amount of active heparin bound to a catheter surface: 1) a kinetic assay based on the inactivation of thrombin by antithrombin III, and 2) thrombin uptake. Both assays were used to estimate the amount of heparin activity on a series of catheters coated with no heparin, covalently bound heparin, and ionically bound heparin. The kinetic assay produced estimates of surface-bound heparin activity and showed that some binding methods resulted in destruction of most of the heparin's biologic activity.

View Article and Find Full Text PDF

Seventeen intraoperative spinal sonographic examinations were performed in 14 patients with intramedullary spinal cord neoplasms. Results of the ultrasound exams were correlated with preoperative imaging studies, surgical findings, and histopathologic analysis of the tumors. Intraoperative spinal sonography accurately localized the intramedullary tumors, often revealing the need for extension of the initial laminectomy.

View Article and Find Full Text PDF