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C Thompson

Publications and source records attributed to C Thompson.

At least 361 records · Page 20Linked to original sources
PubMed1986

Recurrent pregnancy-induced polyuria and thirst due to hypothalamic diabetes insipidus: an investigation into possible mechanisms responsible for polyuria.

A young patient developed hypothalamic diabetes insipidus due to histiocytosis in infancy and was satisfactorily treated with Pitressin. As a teenager she no longer had thirst or polyuria after treatment was stopped. These symptoms only returned during her two pregnancies. When non-pregnant her urine output was 1.7-2.0 1/24 h, basal plasma osmolality 288-290 mOsm/kg, and during pregnancy 24 h urine volume was 4.5-5.21, plasma osmolality 278-280 mOsm/kg. Studies on osmoregulation of thirst and AVP release, and on renal sensitivity to the V2 agonist desmopressin and endogenous vasopressin were performed in pregnant and non-pregnant states. She had no circulating antibodies to AVP, and the effect of pregnancy-associated vasopressinase was eliminated. Results showed lowered basal plasma osmolality and osmolar thirst threshold in pregnancy but no failure of the renal concentrating mechanism. Plasma AVP concentrations after osmotic stimulation were lower in pregnancy. We propose that she developed thirst and polyuria during pregnancy because of lowering of her osmolar thirst threshold to plasma osmolalities which caused her to drink sufficient quantities of fluid to further reduce AVP secretion. We cannot exclude, however, the possibility that there was increased clearance of circulating AVP.

Adult↗
PubMed1986

HLA and autoimmune endocrine disease 1985.

We typed patient groups with type I diabetes (n = 78), Graves' disease (n = 81), goitrous autoimmune (n = 52), "silent" (n = 18) and postpartum thyroiditis (n = 15) for human leucocyte antigens (HLA) A, B, C, DR and DQ. The results were compared to those obtained from 256 healthy controls typed for HLA-A, -B, -C and 140 typed for -DR. All these 140 controls were genotyped. Previously described associations of DR3 (OR (odds ratio) = 2.68, p less than 0.005) and DR4 (OR = 3.26, p less than 0.0001) in type I diabetes is confirmed. In this series, however, HLA-DR3/DR4 heterozygotes were apparently at no greater risk for type I diabetes than DR3 or DR4 homozygotes. The relative risk conferred by DR3/DR4 heterozygotes (6.48) was less than that for DR3 homozygosity (2.8), suggesting a recessive major histocompatibility complex-related susceptibility to type I diabetes. Graves' disease was associated with DR3 (OR = 3.02, p less than 0.0005); the increased frequency of DR3 homozygotes in this series is consistent with recessive HLA-linked susceptibility to Graves' disease proposed on the basis of family data. Hashimoto's thyroiditis, on the other hand, was associated with HLA-DR4 (OR = 3.08, p less than 0.0001), the latter finding confirming our earlier report on 21 patients. The increase of HLA-DR4 in both post-partum and silent thyroiditis suggests that these conditions are immunogenetically related, and may well represent variants of chronic autoimmune thyroiditis.

Autoimmune Diseases↗
PubMed1986

Increased gentamicin nephrotoxicity in normal and diseased dogs administered identical serum drug concentration profiles: increased sensitivity in subclinical renal dysfunction.

Attempts to avoid gentamicin-induced nephrotoxicity in the presence of renal dysfunction assume that the nephrotoxicity threshold is unchanged from that of the normal patient. The purpose of the present study was to compare the response of the subclinically diseased kidney to the normal kidney when exposed to identical serum concentrations of gentamicin. This study used exponentially declining infusions based on preinfusion pharmacokinetics to achieve identical serum gentamicin concentration profiles in intact (intact-gentamicin) and subtotally nephrectomized (nephrectomized-gentamicin) beagle dogs. After 10 daily 12-hr infusions, relative nephrotoxicity was compared using serum chemistries and histopathologic analysis in intact- and nephrectomized-control (untreated) dogs. For intact-gentamicin and nephrectomized-gentamicin dogs, respectively, infusion steady-state serum concentrations were 5.3 +/- 0.3 vs. 5.5 +/- 0.5 (microgram/ml) and elimination rates were 0.19 +/- 0.02 vs. 0.20 +/- 0.01(hr-1) (mean +/- S.E.M.). Postinfusion histopath scoring of renal lesions (0-30, with 30 being most severe) were 11 +/- 5 (nephrectomized-gentamicin), 4 +/- 2 (nephrectomized-control), 2 +/- 2 (intact-gentamicin) and 0 +/- 0 (intact-control). Gentamicin-induced renal dysfunction in nephrectomized dogs was characterized further by administering nonindividualized multiple dosage regimens. Toxicity in the subclinical disease state was marked by oliguria and acute renal failure in contrast to the mild polyuria seen in intact animals. These findings support increased sensitivity to gentamicin nephrotoxicity in dogs with mild renal dysfunction secondary to subtotal surgical nephrectomy.

Animals↗
PubMed1986

Lack of association of HLA with thyroid cancer. An effect of iodine sufficiency and safe environment?

We examined HLA association with differentiated thyroid carcinoma in 45 patients from Newfoundland. No association was found. This finding contrasts with the description of an association of thyroid cancer with HLA-DR1 in Italy and Hungary (iodide deficient areas) and with DR7 in the American mid-west. We suggest that iodide deficiency predisposes DR1 + individuals to thyroid cancer and that this risk is negated by iodide sufficiency unless some other risk factor supervenes.

Adenocarcinoma↗
PubMed1986

Hematuria: a clinical approach.

Microscopic hematuria is no less significant than gross hematuria, since either may signify such pathology as a neoplastic lesion, urinary tract infection, renal calculus, prostatic disease or glomerulonephritis. Anatomic imaging of the urinary tract with intravenous urography and cystoscopy is often indicated in the evaluation of the patient with hematuria. When hematuria is associated with red blood cell casts and/or heavy proteinuria, think of renal parenchymal lesions, particularly of glomerular origin.

Diagnosis, Differential↗
PubMed1985

Fe(III).ATP complexes. Models for ferritin and other polynuclear iron complexes with phosphate.

Polynuclear iron complexes of Fe(III) and phosphate occur in seawater and soils and in cells where the iron core of ferritin, the iron storage protein, contains up to 4500 Fe atoms in a complex with an average composition of (FeO.OH)8FeO.OPO3H2. Although phosphate influences the size of the ferritin core and thus the availability of stored iron, little is known about the nature of the Fe(III)-phosphate interaction. In the present study, Fe-phosphate interactions were analyzed in stable complexes of Fe(III).ATP which, in the polynuclear iron form, had phosphate at interior sites. Such Fe(III).ATP complexes are important not only as models but also because they may play a role in intracellular iron transport and in iron toxicity; the complexes were studied by extended x-ray absorption fine structure, EPR, NMR spectroscopy, and measurement of proton release. Mononuclear iron complexes exhibiting a g' = 4.3 EPR signal were formed at Fe:ATP ratios less than or equal to 1:3, and polynuclear iron complexes (Fe greater than or equal to 250, EPR silent at g' = 4.3) were formed at an Fe:ATP ratio of 4:1. No NMR signals due to ATP were observed when Fe was in excess (Fe:ATP = 4:1). Extended x-ray absorption fine structure analysis of the polynuclear Fe(III).ATP complex was able to distinguish an Fe-P distance at 3.27 A in addition to the octahedral O at 1.95 A and 4-5 Fe atoms at 3.36 A. The Fe-O and Fe-Fe distances are the same as in ferritin, and the Fe-P distance is analogous to that in another metal-ATP complex. An observable Fe-P environment in such a large polynuclear iron cluster as the Fe(III).ATP (4:1) complex indicates that the phosphate is distributed throughout rather than merely on the surface, in contrast to earlier models of chelate-stabilized iron clusters. Complexes of Fe(III) and ATP similar to those described here may form in vivo either as normal components of intracellular iron metabolism or during iron excess where the consequent alteration of free nucleotide triphosphate pools could contribute to the observed toxicity of iron.

Adenosine Triphosphate↗
PubMed1985

The effects of alaproclate on the pupillary responses to tyramine, phenylephrine and pilocarpine in depressed patients.

Nine depressed patients were treated with alaproclate, a selective 5-HT uptake inhibitor, for 3 weeks in a dose of 400 mg daily. The pupillary responses to tyramine, phenylephrine, and pilocarpine eye drops were measured on consecutive days before, after 1 week and after 3 weeks of treatment. The tyramine-induced mydriasis was unaffected by alaproclate, suggesting that it does not significantly inhibit the reuptake of noradrenaline. The pilocarpine-induced miosis and the phenylephrine-induced mydriasis were both enhanced after 1 week but not after 3 weeks of treatment. This suggests that alaproclate acutely increases the responsiveness of postsynaptic muscarinic and alpha 1 adrenoceptors.

Alanine↗
PubMed1985

Clinical studies of the effect of (+) and (-)-oxaprotiline upon noradrenaline uptake.

In six normal male subjects the mydriatic effect of tyramine eye drops was inhibited by 1 day's treatment with desipramine and the (+)- but not the (-)-enantiomer of oxaprotiline. In the same experiment, the secretion of melatonin was increased after treatment with (+)- but not with (-)-oxaprotiline. The effects of (+)-oxaprotiline and of desipramine treatment were similar, as were those of (-)-oxaprotiline and placebo. These findings extend to clinical studies the demonstration in animal experiments of stereo-specificity for the effects of (+)- and (-)-oxaprotiline upon noradrenaline uptake. A comparison of the effects of the two enantiomers should provide an ideal strategy for studying effects of noradrenaline uptake blockade in clinical studies.

Anthracenes↗
PubMed1985

Characterization of platelet alpha 2 adrenoceptors and measurement in control and depressed subjects.

The alpha-adrenoceptor on platelets has been characterized using 3H-yohimbine, 3H-dihydroergocriptine, and 3H-clonidine. The receptor, which exhibits the characteristics of an alpha 2-type, has a Bmax for dihydroergocriptine of 330 fmoles/mg protein, for yohimbine of 178 fmoles/mg protein, and for clonidine of 38 fmoles/mg protein. Clonidine, but not yohimbine binding, is decreased by the presence of K+, Na+, or Li+. Adenosine triphosphate (ATP) and the guanosine triphosphate (GTP) analogue, Gpp(NH)p, reduce the affinity of clonidine for its binding site. Acute exercise, such as playing squash, does not apparently alter the Bmax or Kd of 3H-yohimbine binding to platelet membranes, and in vitro studies, with intact platelets or platelet membranes, show that incubation with adrenalin (10 microM) does not induce alterations in Bmax or Kd. In the present study, no correlation was found between age and alpha 2-adrenoceptor numbers. There was no significant difference in the Bmax for 3H-yohimbine binding to platelet membranes from control and depressed subjects, although the mean value for the depressed group was some 10% lower than that for the corresponding control group. There were no overall significant and consistent effects of desipramine (DMI) treatment. After 2-3 days of treatment, the Bmax was reduced by 20%, after 7 days by 14%, and after 21 days it was 8% above the control value. When an additional group of patients on DMI (7 days of treatment) was analyzed using one supramaximal concentration of 3H-yohimbine, there was a significant decrease (25%) in binding.

Adult↗
PubMed1985

Post-partum thyroiditis and goitrous (Hashimoto's) thyroiditis are associated with HLA-DR4.

Using new panels of HLA-DR typing sera, we found an increase in the prevalence of HLA-DR4 in 21 patients with Hashimoto's thyroiditis (57%) and 32 patients with post-partum thyroiditis (53%) compared to controls (21%). Hashimoto's thyroiditis was previously found to be associated with HLA-DR5 and Dw5. We feel that the doubts raised by this study warrant the study of DR antigens in thyroid autoimmune disease using large panels of specific sera.

Diabetes Mellitus, Type 1↗
PubMed1985

The power to pollute and the power to preserve: perceptions of female power in a Hindu village.

In traditional Hindu village society, women are seen as having the power to pollute men. Such beliefs denigrate certain aspects of female sexuality. A detailed examination of these beliefs reveals that female sexuality is only associated with pollution and negative forces when women become estranged from men through their biology or other circumstances. When associated with pollution women are perceived as being in danger as well as endangering others. In contrast when women identify their interests with men's they are not in danger and can exercise positively valued powers such as the power to preserve life. The nexus of beliefs connected with female pollution and other mystical powers encourages women to subordinate their interests to men's.

Ethnicity↗
PubMed1985

Affinity-purified interleukin 2 induces proliferation of large but not small B cells.

Immunoaffinity-purified interleukin 2 (IL2) stimulated proliferation of large but not small B cells. Stimulation was observed even when B cells were cultured at very low cell densities (3 X 10(4) per microwell containing 0.2 ml of medium). Addition of small numbers of purified splenic T cells did not enhance the IL2-induced B-cell proliferative response. These results suggest that IL2 was not operating through contaminating T cells. B cells cultured with anti-Ig antibody in vitro showed enhanced proliferation when cultured with EL4 thymoma-derived B-cell growth factor but not when cultured with IL2. A direct role for IL2 in B-cell activation is discussed.

Animals↗
PubMed1985

A new breast carcinoma antigen defined by a monoclonal antibody.

A new monoclonal antibody (MoAb), 3E1-2, to human breast carcinoma cells was made. With the use of the immunoperoxidase technique, 3E1-2 was tested on Formalin-fixed and fresh sections of 27 normal and 81 neoplastic tissues, including 37 carcinomas of the breast, 15 lung tumors, 5 colon tumors, and other tumors. Strong uniform staining of the cytoplasm and membrane occurred with the breast carcinoma, whereas with normal breast tissue less intense staining of the luminal membrane was seen; not all cells were reactive with the MoAb. Most other human tumors (with the exception of some lung, kidney, and uterine carcinomas) were nonreactive, and few normal tissues were reactive. The unique features of this new MoAb are: a) reaction with Formalin-fixed as well as fresh tissue; b) lack of a reaction with the cell surface of 43 established cell lines, including 10 lines derived from breast carcinoma cultures; c) variable staining patterns in different breast carcinomas, varying from all cells staining to dense cytoplasmic staining to minimal membrane staining of a few cells; d) a great differential in staining patterns between normal and neoplastic tissue (nonetheless, some normal tissues were 3E-1.2+). The antibody does not detect a tumor-specific antigen, but has a high carcinoma-to-normal breast ratio of staining. In addition, preliminary studies on the sera of 20 patients with carcinoma of the breast have shown that the antigen detected by 3E1-2 is elevated in their serum; 3E1-2 thus has the potential to be used for diagnosis of this disease.

Animals↗
PubMed1985

Circadian rhythms.

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Circadian Rhythm↗
PubMed1985

The effect of desipramine upon melatonin and cortisol secretion in depressed and normal subjects.

Melatonin and cortisol values in plasma were measured hourly over 24 hours in six depressed patients and six normal volunteers before treatment and after one and three weeks of treatment with desipramine. The normal volunteers were further tested one week after withdrawal of desipramine. The mydriatic effects of tyramine and phenylephrine eye drops were also recorded in the normal volunteers. In neither group of subjects did desipramine treatment reduce melatonin secretion, suggesting that functionally significant down-regulation of beta andrenoceptors was not caused by this treatment. Melatonin secretion was significantly increased after three weeks of treatment in depressed patients. This increase was not found in normal subjects.

Adolescent↗