Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020437 (hypercalcemia)
 10,293 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the experimentally-induced hyper- or hypoglycemic state, perilymph glucose concentration paralleled the blood concentration, although a delay of about one hour was observed between the time of maximum concentration of glucose in perilymph and its concentration in blood. In hypercalcemia, perilymph calcium concentration steadily increased over a three-hour period, although blood calcium concentration fluctuated during this time. After an initial increase in the CSF calcium concentration, there were insignificant changes during the second and third hours. In animals with thyrocalcitonin-induced hypocalcemia, although blood calcium concentration steadily decreased, its concentration in perilymph and CSF remained practically constant. The present findings suggest that the chemical composition of perilymph can be altered by changing the blood concentration of glucose or calcium. The marked difference of behavior noted between glucose and calcium in these experiments would indicate the existence of different mechanisms for maintaining the homeostatic state for these two substances.
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PMID:The effect on perilymph of the alteration of serum glucose or calcium concentration. 105 75

To understand the etiology of bone modulation and hypercalcemia observed in granulocytosis of a tumor-bearing animal model and to gain insight into the implication of sustained hematopoietic stimulation on the bone tissue, in vivo responses of normal mouse hematopoietic and bone tissues to long-term injections of recombinant human and murine granulocyte colony-stimulating factor (G-CSF), murine granulocyte-macrophage CSF (GM-CSF), and human erythropoietin were quantitatively analyzed. Osteoclast activation was estimated by the osteoclast-endosteal ratio, determined by morphometric analyses of femoral sections. Medullary and bone areas were measured on transverse ground bone sections of the tibia. Recombinant murine G-CSF provoked marked granulocytosis associated with significant increases in the number of marrow granulocytes and their progenitors, and caused expansion of granulopoietic marrow into fatty marrow. The bone of G-CSF-treated mice showed a significant increase in endosteal osteoclast numbers with medullary area enlargement and a reduction in the bone thickness; indicative of endosteal bone resorption. Although GM-CSF had little effect on granulopoiesis, it caused peritoneal macrophages to increase and induced similar bone changes as those observed in G-CSF treatment. Enhanced erythropoiesis stimulated by erythropoietin was also associated with evidence of endosteal bone resorption. Bone changes induced by these growth factors were not associated with hypercalcemia. These animal studies document association of bone modulation in sustained stimulation of hematopoiesis, and implicate important physiologic effects of hematopoietic growth factors on skeletal tissue in vivo.
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PMID:Bone modulation in sustained hematopoietic stimulation in mice. 170 70

When bone-marrow cells from patients with multiple myeloma (MM) were seeded in short-term cultures, a spontaneous proliferation of the myeloma cells occurred for most of the patients with active disease and proliferating myeloma cells in vivo. In all cases, this spontaneous proliferation was inhibited by anti-IL-6 monoclonal antibodies (mabs). Moreover, myeloma cell lines, completely dependent upon exogenous IL-6 for their growth, could be reproducibly established by initially stimulating the myeloma cells with both IL-6 and GM-CSF. These results demonstrate that IL-6 is a major paracrine myeloma-cell growth factor in vitro. High serum IL-6 levels were observed in MM patients with active disease, especially patients with terminal disease. High IL-6 mRNA levels were found in bone-marrow cells of MM patients, mainly in myeloid and monocytic cells, in vivo. The myeloma cells did not express IL-6 mRNA. Injection of anti-IL-6 mabs to MM patients with terminal disease and extramedullary proliferation, completely blocked the myeloma-cell proliferation in vivo and completely inhibited the serum IL-6 bioactivity and the serum CRP levels. One patient with plasma cell leukemia and hypercalcemia was treated for two months with anti-IL-6 mabs and maintain in remission for 2 months without major side effects. Interestingly, the serum calcium levels also decreased in these patients. All these results show that IL-6 is the main cytokine responsible not only for the myeloma-cell proliferation in vivo, but presumably also for the large bone resorption processes observed in human MM.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Interleukin-6 is the central tumor growth factor in vitro and in vivo in multiple myeloma. 210 41

A cell line was established from undifferentiated giant cell carcinoma of the thyroid. The authors obtained cells from a 44-year-old patient admitted because of a rapidly growing anterior neck mass. The patient had significant leukocytosis and hypercalcemia shortly before her death. An autopsy revealed epidermoid metaplasia of the tumor cells. The cells (HTC/C3) had lost most of their differentiated functions. However, their thyroid nature was shown by peroxidase staining and by enzyme-linked immunostaining with Hashimoto patients' sera. The tumor extract was found to contain parathyroid (PTH)-like activity. Significant amounts of colony stimulating factor (CSF), which was further defined to be GM-CSF, and interleukin-1 alpha (IL-1 alpha) were detected in the conditioned media. Epidermal growth factor (EGF) binding to the HTC/C3 showed rich EGF receptors. Furthermore, the conditioned medium inhibited the binding of 125I-mEGF to HeLa cells, and transforming growth factor (TGF) was found repeatedly in the media.
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PMID:Establishment of a human undifferentiated thyroid cancer cell line producing several growth factors and cytokines. 219 88

Transplantation of a murine mammary carcinoma (CE maca) into mice induces marked granulocytosis and hypercalcemia secondary to excessive bone resorption. Such responses are not induced by another murine mammary carcinoma Bc66. In order to understand the mechanisms of these unique phenomena, we analyzed mRNA of tumor cells for expression of murine granulopoietic growth factors and studied interactions of tumor-derived factors using antiserum to a growth factor in vitro and in vivo. The Northern blot analysis of CE tumor clones revealed the expression of granulocyte colony stimulating factor (G-CSF) and macrophage colony stimulating factor (M-CSF), but no other CSF genes, while the Bc66 clone expressed only M-CSF. The G-CSF and M-CSF gene expression in CE tumor clones was accompanied by secretion of these proteins in culture. The granulocyte stimulating activity of CE tumor-derived G-CSF or recombinant human G-CSF was markedly enhanced by purified M-CSF in vitro. Significant but variable neutrophilia was observed in mice inoculated with CE tumor clones. Anti-M-CSF treatment of CE tumor-bearing mice significantly reduced neutrophilia, but did not affect hypercalcemia. These studies document that G-CSF and M-CSF are produced constitutively from the CE maca, and G-CSF is likely responsible for granulocytosis induced by this tumor. G-CSF and M-CSF function synergistically in granulocyte stimulation in vitro and this synergism may also play a role in marked granulocytosis of tumor-bearing animals, providing further evidence of the effect of CSFs in vivo.
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PMID:Mechanisms of tumor-induced neutrophilia: constitutive production of colony-stimulating factors and their synergistic actions. 247 93

Male Fischer-344 rats, 21 days old, were fed diets containing 0 (LOD), 2,200 (CONT), or 440,000 (HID) international units of vitamin D3 per kilogram for 12 weeks. [Ca] was measured in plasma, CSF, brain, and choroid plexus. In addition, 45Ca and 36Cl transfer coefficients (KCa and KCl) for uptake from blood into CSF and brain were determined. Although plasma ionized [Ca]s in LOD and HID rats were 50% and 136%, respectively, of values in CONT animals, CSF and brain [Ca]s ranged from only 85% to 110% of respective CONT values. Choroid plexus [Ca] was increased by 37% after HID diet, but was decreased only 10% after LOD. KCa values at CSF, parietal cortex, and pons-medulla were negatively correlated with plasma ionized [Ca], whereas KCl values at CSF and brain were not different between the diet groups. The findings demonstrate that central nervous system [Ca] is maintained during chronic hypo- or hypercalcemia by saturable transport of Ca at brain barrier membranes. This transport does not seem to involve modulation by 1,25-dihydroxyvitamin D3.
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PMID:Regulation of brain and cerebrospinal fluid calcium by brain barrier membranes following vitamin D-related chronic hypo- and hypercalcemia in rats. 284 85

Hypercalcemia of cancer is due to secretion of substances with parathyroid hormone (PTH)-like activity from tumours of the respiratory, gastrointestinal and urogenital tract as well as hematologic malignancies and breast cancer. PTH-related Protein (PTHrP) is secreted mainly from solid tumours and it has been recently recognized as being responsible for hypercalcemia mediated primarily via an increased renal reabsorption of calcium and secondly by an increased bone resorption. PTHrP-mRNA is expressed in a variety of normal tissues and has multiple physiologic and paracrine actions. Bone resorbing factors like the cytokines-lymphokines, interleukins, prostaglandins, TNF-alpha/TNF-beta, GM-CSF/G-CSF, TGF-alpha and TGF-beta are produced by certain solid and hematologic cancers and have also been implicated in tumour-induced hypercalcemia. The recently introduced PTHrP antagonists are hopeful therapeutic measures for the future.
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PMID:Hypercalcemia of cancer: an update. 835 38

Partial remission of a centroblastic non-Hodgkin's lymphoma, clinical stage IV A, in a 79-year-old man was achieved by six courses of chemotherapy with epirubicin, cyclophosphamide and vincristine. The only residual finding was a palpable small cervical lymphoma. After a treatment pause of about 6 weeks increasing hypersalivation set in which ultimately made food intake impossible and led to a breakdown in the patient's general state. Findings in the region of the head, neck, throat and the base of the skull were unremarkable, but cerebrospinal fluid contained 1300/3 cells, almost all of them lymphoblasts. After five intrathecal injections of at first 15 mg methotrexate and 4 mg dexamethasone each, followed by five more with 40 mg cytarabine added to them, the CSF cell count became normal. At the same time salivation clearly decreased and food intake became once again possible. The patient died 5 months later from hypercalcaemia due to osseous infiltrations. Until his death there was no recurrence of the hypersalivation as the cardinal sign of meningeal carcinomatosis.
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PMID:[Hypersalivation as a leading symptom of neoplastic meningiosis in highly malignant non-Hodgkin's lymphoma]. 842 Jul 69

This study examined the potential roles of the plasma membrane Ca2+-ATPase (PMCA) at the blood-CSF and blood-brain barriers in brain Ca2+ homeostasis and blood-brain barrier Na+/K+-ATPase subunits in brain K+ homeostasis. During dietary-induced hypo- and hypercalcemia (0.59+/-0.06 and 1.58+/-0.12 mM [Ca2+]) there was no significant change in choroid plexus PMCA (Western Blots) compared to normocalcemic rats (plasma [Ca2+]: 1.06+/-0.11 mM). In contrast, PMCA in cerebral microvessels isolated from hypocalcemic rats was 150% greater than that in controls (p<0.001). Comparison of the alpha3 subunit of Na+/K+-ATPase from cerebral microvessels isolated from hypo-, normo- and hyperkalemic rats (2.3+/-0.1, 3.9+/-0.1 and 7. 2+/-0.6 mM [K+]) showed a 75% reduction in the amount of this isoform during hyperkalemia. None of the other Na+/K+-ATPase isoforms varied with plasma [K+]. These results suggest that both PMCA and the alpha3 subunit of Na+/K+-ATPase at the blood-brain barrier play a role in maintaining a constant brain microenvironment during fluctuations in plasma composition.
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PMID:Blood-brain barrier mechanisms involved in brain calcium and potassium homeostasis. 987 35

Human T-cell lymphotropic virus type I (HTLV-I) is associated with various clinical disorders including adult T cell leukemia, myelopathy, arthropathy. Hypercalcemia resulting from osteoclast activation and a variety of hematopoietic abnormalities have been also observed in HTLV-I infected patients, however, precise mechanism about initial trigger(s) prior to presenting symptoms is still unknown. In this study, to assess effects of HTLV-I on hematopoiesis, we analysed characteristics of early hematopoietic precursors in HTLV-I env-pX transgenic rats. Progenitor cells for osteoclasts were significantly increased even in the marrow of asymptomatic env-pX rats. Progenitors for B cells were also highly enriched, while colony forming cells (CFC) elicited by GM-CSF(CFU-GM) and M-CSF(CFU-M) were comparable to normal littermates. Following arthritis in env-pX transgenic rats, osteoclastogenesis was further augmented and the CFCs were increased. Bone marrow cells carrying adjuvant-induced arthritis retained a constant number of progenitors for osteoclast and B lymphocytes, whereas the number of CFU-GM and CFU-M increased. These results indicate that the env-pX transgene affect early stages of osteoclast and B-cell lineages prior to developing diseases, in contrast, an increase of the CFCs was caused indirectly by arthritis. This study provides a novel standpoint for the mechanisms of pathogenesis by HTLV-I.
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PMID:Promotion of early osteoclastogenesis and B lymphopoiesis in the bone marrow of transgenic rats with the env-pX gene of human T-cell lymphotropic virus type I. 988 97


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