Biomedical subjects

D Teller

Publications and source records attributed to D Teller.

14 recordsLinked to original sources

PubMed1997

Posttraumatic cervical osteophytosis causing progressive dysphagia.

Dysphagia is a commonly encountered patient complaint. The differential diagnosis for dysphagia is extensive. One long-recognized etiology of dysphagia is cervical osteophytosis. Degenerative joint disease, ankylosing spondylosis, and diffuse idiopathic skeletal hyperostosis (DISH) can all cause cervical osteophyte formation. We describe a patient with dysphagia and a large cervical osteophyte. Our case illustrates cervical osteophytosis associated with a history of previous cervical spine trauma. Evaluation and management strategies are discussed.

Aged↗

PubMed1990

Early effects of subtotal nephrectomy and food restriction on urinary calcium in the rat.

Urinary calcium excretion (UCa) is normal several weeks following subtotal nephrectomy (Nx) in the rat, despite factors such as magnified solute load per nephron which should promote hypercalciuria. To define the levels of UCa during the first few weeks after Nx and to determine if the development of compensatory mechanisms governing renal conservation of calcium are detectable, we measured UCa in Nx and sham Nx rats with matched food intake (10 g/day) from 10 days before through 20 days following Nx. In the sham Nx animals, UCa rose during the first 5 days following surgery from 27 +/- 8 to 66 +/- 5 microM/day and then plateaued for the remaining time. In Nx rats, UCa also rose during the first 5 postoperative days from 23 +/- 5 to 110 +/- 10 microM/day (Nx vs. sham Nx, p less than 0.05), but then fell over the next 3 days to levels observed simultaneously in sham Nx animals. The rise in UCa after Nx, but not after sham Nx, was associated with a doubling of urine flow rate and increased urinary titratable acid excretion. In parathyroidectomized rats, UCa also rose following Nx; however, maximum UCa was then sustained for at least 4 days. In an additional sham Nx group fed 20 g/day, no increase in UCa occurred following surgery. Thus, hypercalciuria is present following Nx in the rat, in part possibly attributable to increased acid excretion. The transient nature of calciuria reflects an adaptive phenomenon, most likely hyperparathyroidism. Diminished food intake following surgery independently contributes to hypercalciuria, regardless of the status of renal mass.

Animals↗

PubMed1990

Bilateral mammary artery bypass and sternal dehiscence. A favorable outcome.

The efficacy of mammary artery bypass for coronary artery disease has been well established. The present retrospective series of consecutive patients was scrutinized to assess the incidence of sternal dehiscence following myocardial revascularization using the right and left internal mammary arteries. For comparison, the consecutive group of patients undergoing myocardial revascularization with unilateral internal mammary artery bypass was analyzed for similar sternal complications. In a consecutive series of patients, 277 patients underwent myocardial revascularization using the right and left internal mammary arteries for bypass. The overall operative mortality in this group of patients was 0.722 per cent. In this group there was an overall incidence of seven sternal dehiscences, both partial and complete for an incidence of 2.52 per cent. Upon analysis, it was shown that the female sex and diabetes were the conditions that most likely predisposed to the occurrence of sternal dehiscence whether partial or complete. For comparison, a consecutive group of 413 patients were analyzed for similar demographic data and results. The overall operative mortality in this group was 1.21 per cent. The overall incidence of sternal dehiscence both partial and complete, was 0.484 per cent. Both instances of sternal dehiscence occurred in diabetic patients and the data indicates, as in the bilateral internal mammary artery group, the presence of diabetes predisposed to the occurrence of this complication. The low overall incidence of sternal dehiscence in the expanded use of the mammary arteries should not deter the surgeon from aggressive use of the mammary arteries. One should use caution, however, in using bilateral mammary artery grafts in diabetics, women, and to a lesser extent, patients more than 70 years of age.

Adult↗

PubMed1989

Effects of acute and chronic acyclovir on canine renal function.

Acyclovir-associated renal dysfunction is difficult to study in humans because it occurs in patient populations who are generally receiving multiple medicines concurrently and dysfunctions occur infrequently. We studied the effects of two regimens of acyclovir treatment, a short-term high dose (210 mg/kg/day for 43 hr) via constant infusion and a chronic lower dose by intermittent infusion (15 mg/kg, 3 times/day for 28 days), on selected renal functions in dogs. Urine concentrating capacity as compared to base-line and controls declined during both the short-term (40% decline) and chronic treatments (36% decline). The persistence of the concentrating deficit in the presence of stimulation with vasopressin suggested that the defect resided in the renal response to vasopressin. Glomerular filtration rates significantly decreased during the acute high-dose treatment (from 104 +/- 15 to 87 +/- 11 ml/min) but not during the chronic low-dose treatment. Both acyclovir treatments were associated with a small but significant decline (approximately 10% for both studies) in the plasma potassium concentrations although an increase in urine potassium clearance could not be demonstrated. We conclude that acyclovir can cause renal dysfunction in healthy animals at plasma concentrations higher but comparable to those achieved clinically. Although both treatment regimens decreased renal function, the shorter high-dose regimen which maintained acyclovir plasma concentrations was more detrimental than the longer exposure to a lower dose of the drug given intermittently. The data suggest that renal dysfunction is not related to a rare sensitivity, as all acyclovir-treated animals showed subtle decrements in renal function.

Acyclovir↗

PubMed1988

The Nucleic Acid Blot Analyzer II. ANALYZE, an image analysis software package for molecular biology.

The Nucleic Acid Blot Analyzer, a new instrument providing high-speed imaging of 32P labeled nucleic acids, captures, stores and presents images in digital form, thus lending itself to rapid data handling and analysis as well as replacing conventional X-ray film autoradiography for many applications. A software package called ANALYZE has been specifically designed for the instrument in order to provide automatic or semi-automatic analysis for molecular biological techniques. The software includes image display manipulation, quantitative and positional analysis, as well as file maintenance utilities. The specific application of the software/hardware to various techniques is presented.

Molecular Biology↗

PubMed1986

Detection of an alcohol specific product in urine of alcoholics.

A simple procedure, using high performance liquid chromatography, was developed to detect and measure in urine an alcohol specific product, "ASP" indicative of chronic alcohol consumption. One day after hospital admission, the average amount of ASP in urine of alcoholics was 17 times higher than that of control subjects and 5 and 2 times higher after 7 and 14 days of abstinence, respectively. Urinary levels of ASP should be of value in the identification of chronic alcoholism.

Alcohol Drinking↗

PubMed1982

Reconstitution of types I and II adenosine cyclic 3',5'-phosphate dependent protein kinase.

Fluorescence intensity and anisotropy measurements using the fluorescent adenosine cyclic 3',5'-phosphate (cAMP) analogue 1,N6-ethenoadenosine cyclic 3',5'-phosphate (epsilon-cAMP) are sensitive to the dissociation of epsilon-cAMP which occurs when either the type I or the type II regulatory subunit (RI or RII) of cAMP-dependent protein kinase associates with the catalytic subunit. Studies using epsilon-cAMP show that MgATP has opposite effects on the reconstitution of both types of protein kinase: MgATP strongly stabilizes the type I holoenzyme while it slightly destabilizes the type II holoenzyme. The synthetic substrate Kemptide has a small inhibitory effect on the reconstitution of both holoenzymes when tested at 10 microM concentration. The protein kinase inhibitor has a larger effect which is especially pronounced in the reassociation of the type I enzyme. The diminished relative ability of the type I regulatory subunit to compete with the protein kinase inhibitor suggests that the combined effects of the two opposing equilibria (epsilon-cAMP and catalytic subunit binding) are different for the two types of regulatory subunits. Displacement experiments show that cAMP and epsilon-cAMP bind about equally well to the type I subunit. Slow conformational changes accompanying the binding of epsilon-cAMP by both regulatory subunits are greatly accelerated with the holoenzymes, suggesting that dissociation of the holoenzymes occurs via ternary complexes. The time courses of epsilon-cAMP binding also show the heterogeneity of binding characteristics of RII. The 37 000-dalton fragment of type II subunit retains the epsilon-cAMP binding properties of the native subunit. However, only a fraction of the fragment preparation (approximately 32% estimated from sedimentation measurements) binds the catalytic subunit well, suggesting heterogeneity of cleavage.

Adenosine Triphosphate↗

PubMed1982

Binding of 5,5'-bis[8-(phenylamino)-1-naphthalenesulfonate] by the regulatory subunits of adenosine cyclic 3',5'-phosphate dependent protein kinase.

Binding to the regulatory subunits of types I and II adenosine cyclic 3',5'-phosphate (cAMP) dependent protein kinase (RI and RII, respectively) produces large distinctive increases in fluorescence and optical activity of 5,5'-bis[8-(phenylamino)-1-naphthalenesulfonate] [bis(ANS)]. Both specific and nonspecific interactions are involved. Association of the regulatory subunits with either the catalytic subunit or cAMP results in dissociation of a major portion of the bound bis(ANS) as detected by changes in fluorescence and circular dichroism. The results are consistent with the accepted cAMP binding properties of RI and RII, showing cooperativity in case of RI and two heterologous binding sites for RII. cGMP has the same overall effect on bis(ANS) binding as cAMP. However, very high concentrations are required for complete dissociation of bis(ANS) from RII, consistent with the observation that cGMP is inefficient in bringing about the dissociation of the type II holoenzyme. Magnesium binding to sites having dissociation constants of ca. 12 mM increases the interaction of bis(ANS) with both of the isolated regulatory subunits. Experiments involving the 37 000-dalton fragment of RII indicate that the limited proteolytic cleavage was heterogeneous, with only 24-39% of the resulting population interacting strongly with the catalytic subunit.

Anilino Naphthalenesulfonates↗

PubMed1976