Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020672 (hypothermia)
 17,327 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of prolonged light halothane anesthesia (0.8%) on the proliferation rate of different mouse tissues was investigated, using [5-125I]5-iodo-2-deoxyuridine uptake into DNA as the test parameter. It was found that DNA synthesis in spleen, femoral bone marrow, and, occasionally, the small intestine was significantly depressed after exposure for 24 hr to halothane in vivo. The time course of DNA synthesis inhibition was then investigated by utilizing a shorter (6-hr) exposure time. This period was found to be insufficient to cause DNA synthesis inhibition in any of test tissues. Because anesthesia was found to be associated with hypothermia at normal room temperatures, it was established that the inhibition of DNA synthesis was not due to cooling of the mice under anesthesia by demonstrating that inhibition in sensitive tissues occurred at warmer temperatures as well. To examine the specificity of this finding, the DNA synthesis rate of cells in other normal tissues, e.g., skin and muscle, and in s.c.-growing tumor cells of a mouse mammary carcinoma, L1210 leukemia, and a first transplant AKR lymphoma were examined. In none were responses noted with 24 hr of halothane exposure. However, halothane was found to inhibit DNA synthesis in regenerating marrow. Finally, it was found that after significant exposure to halothane, complete recovery was seen in the spleen after 24 hr, whereas femur DNA synthesis was still depressed by 20% at the same time.
 ...
PMID:Preferential inhibition of DNA synthesis in mouse hemopoietic cells by halothane. 97 81

To focus attention on the problem of infant mortality in Lebanon, data were compiled on infant mortality from 1978 to 1986 at the American University of Beirut Medical Center. Causes of death are analyzed for 602 males and 398 females. 54.9% deaths occurred at 1 month of age and 77.4% died within the 1st year. Autopsies were performed on .7%. 37.7% of all neonatal deaths were due to neonatal diseases such as hyaline membrane disease, asphyxia neonatorum, immaturity, necrotizing enterocolitis, hemorrhage, hemolysis, meconium aspiration, and kernicterus. Better prenatal care would reduce this group, or the administration of corticosteroids to the mother 24-48 hours prior to delivery, as well as rapid resuscitation at birth and prevention of the 5 curses: hypoxemia, hypoglycemia, hypothermia, hypotension, and acidosis. Although unavailable in Lebanon, administration of surfactants through an endotracheal tube would also help. Infections constitute 25.1% of deaths; many are preventable through adequate public health measures and strict personal hygiene, i.e., diseases such as sepsis, pneumonia, meningitis, gastroenteritis, hepatitis, encephalitis, and 1-2 cases of the following: diphtheria, measles, peritonitis, tetanus, tuberculosis, cytomegalis inclusion, herpes, parathyphoid, pertussis, poliomyelitis, and shigellosis. Congenital diseases were 21.6%. In utero diagnosis could prevent some diseases and in utero treatment is possible for hydrocephalus and hydronephrosis. Screening programs postnatally could lead to treatment. 5.9% were malignancies such as leukemia, lymphoma, brain tumors, histocytosis, Wilm's tumor, Ewing sarcoma, and Hodgkin's disease. Early diagnosis is critical if mortality is to be reduced in this group, but medical advances are still needed. 2.9% are miscellaneous diseases such as poisoning, rheumatic diseases, marasmus, Reye's syndrome, nephrosis, rickets, and epilepsy. Most of these diseases are preventable, except for rheumatic inflammation of the heart. Recommended necessary steps to reduce infant mortality are: prenatal care, diagnosis and screening, intrauterine surgery; resuscitation and intensive care centers with modern equipment and trained personnel; national vaccination and screening programs; adequate public health measures and hygiene; parental education; and well-equipped hospitals to serve all regardless of income level.
 ...
PMID:Pediatric mortality: an avoidable tragedy. 251 28

Chlorpromazine (CPZ) can decrease the toxicity of doxorubicin (DOX). We wanted to determine whether this CPZ pretreatment could affect the response of tumours to therapeutic doses of DOX. Six groups of eight female CDF1 mice received 1 million leukaemia P388D1 cells i.p. For 5 days, they received DOX i.p. (total dose 0, 6 or 12 mg/kg), preceded by saline or 5 mg/kg CPZ s.c. CPZ in the absence of DOX had no effect on survival [median survival time (MST) of 19 days vs. 20]. In mice receiving DOX only, MST was greater than 60 days. Mice receiving DOX + CPZ were similar to DOX till day 25, but subsequently died earlier (MST of 27 and 34 days, for DOX 6 and 12 mg/kg). At death or day 60, 31% (5/16) of DOX mice and 88% (14/16) of DOX + CPZ had macroscopic tumours (P less than 0.005, both DOX dose groups combined). However, only 19% (3/16) of DOX and 6% (1/16) of DOX + CPZ had tumours in the abdominal cavity, the others being in the abdominal wall close to the site of injection. The results suggests that while CPZ did not affect the killing of cancer cells in the abdominal cavity, it did block the effect of DOX on cells in the abdominal wall and skin. This block may be caused by decreased local delivery of DOX, due to the hypothermia produced by CPZ.
 ...
PMID:Ambiguous effect of chlorpromazine on doxorubicin activity against P388D1 tumours in mice. 335 4

A series of pulse-doses of 7, 8, 12-trimethylbenz(a)anthracene-induced leukemia rapidly and consistently in very high yield in rats of Long-Evans (L-E) strain. The predominant type was a diffuse hepatic leukemia of erythroblastic stem cells. Progressive hypothermia and a decline in pituitary function are newly recognized signs of advanced leukemia in rat.
 ...
PMID:Hundred day leukemia: preferential induction in rat by pulse-doses of 7,8,12-trimethylbenz(a)anthracene. 541 51

Scalp hypothermia has been introduced to reduce the temporary epilation associated with certain cytotoxic drugs. This has improved compliance with drug delivery for some patients. It is currently not recommended for use in those tumors with a high prevalence of scalp metastasis, ie, leukemia and lymphoma. We have treated a patient for mycosis fungoides who demanded use of a "cooling cap" while undergoing consolidation chemotherapy. Cutaneous disease recurred on the scalp, with no other evidence of mycosis fungoides. Caution should be used in reducing drug delivery to the scalp while treating tumors manifesting cutaneous stem cell tumor nests.
 ...
PMID:Misuse of scalp hypothermia. 723 71

Merocyanine 540 (MC540)-mediated photodynamic therapy (PDT) inactivates experimental leukemia, lymphoma, and neuroblastoma cells by a singlet oxygen-mediated mechanism but is relatively well tolerated by normal pluripotent hematopoietic stem cells and granulocyte/macrophage progenitors (CFU-GM). MC540 is currently undergoing phase I clinical testing for the extracorporeal purging of autologous bone marrow and peripheral blood stem cells. We report here that performing MC540-mediated PDT at 4.7 degrees C (hypothermia) instead of at ambient temperature enhanced the photoinactivation of L1210 cells and CFU-GM but left the photoinactivation of K562 cells unchanged. Hypothermia reduced dye binding in K562 but not in L1210 cells, whereas the photogeneration of lipid hydroperoxides (LOOH) was affected in neither cell line. Post-PDT incubation at 4 degrees C delayed the decay of LOOH and enhanced the photoinactivation of CFU-GM as well as L1210 and K562 cells. Taken together, these results suggest that hypothermia interfered with the repair of potentially lethal photodynamic damage. They stress the importance of temperature control during and immediately after the photochemical purging of autologous bone marrow and peripheral blood stem cells.
 ...
PMID:Effect of hypothermia on the merocyanine 540-mediated purging of hematopoietic cells. 911 16

Fatty acid amide hydrolase (FAAH) catalyzes the hydrolysis of bioactive fatty acid amides and esters such as the endogenous cannabinoid receptor ligands, anandamide (N-arachidonoyl-ethanolamine) and 2-arachidonoylglycerol, and the putative sleep inducing factor cis-9-octadecenoamide (oleamide). Most FAAH blockers developed to date also inhibit cytosolic phospholipase A2 (cPLA2) and/or bind to the CB1 cannabinoid receptor subtype. Here we report the finding of four novel FAAH inhibitors, two of which, malhamensilipin A and grenadadiene, were screened out of a series of thirty-two different algal natural products, and two others, arachidonoylethylene glycol (AEG) and arachidonoyl-serotonin (AA-5-HT) were selected out of five artificially functionalized polyunsaturated fatty acids. When using FAAH preparations from mouse neuroblastoma N18TG2 cells and [14C]anandamide as a substrate, the IC50s for these compounds ranged from 12.0 to 26 microM, the most active compound being AA-5-HT. This substance was also active on FAAH from rat basophilic leukaemia (RBL-2H3) cells (IC50 = 5.6 microM), and inhibited [14C]anandamide hydrolysis by both N18TG2 and RBL-2H3 intact cells without affecting [14C]anandamide uptake. While AEG behaved as a competitive inhibitor and was hydrolyzed to arachidonic acid (AA) by FAAH preparations, AA-5-HT was resistant to FAAH-catalyzed hydrolysis and behaved as a tight-binding, albeit non-covalent, mixed inhibitor. AA-5-HT did not interfere with cPLA2-mediated, ionomycin or antigen-induced release of [3H]AA from RBL-2H3 cells, nor with cPLA2 activity in cell-free experiments. Finally, AA-5-HT did not activate CB1 cannabinoid receptors since it acted as a very weak ligand in in vitro binding assays, and, at 10-15 mg/kg body weight, it was not active in the 'open field', 'hot plate' and rectal hypothermia tests carried out in mice. Conversely AEG behaved as a cannabimimetic substance in these tests as well as in the 'ring' immobility test where AA-5-HT was also active. AA-5-HT is the first FAAH inhibitor reported to date which is inactive both against cPLA2 and at CB1 receptors, whereas AEG represents a new type of cannabinoid receptor agonist.
 ...
PMID:Arachidonoylserotonin and other novel inhibitors of fatty acid amide hydrolase. 970 57

We reported previously that synthetic amides of polyunsaturated fatty acids with bioactive amines can result in substances that interact with proteins of the endogenous cannabinoid system (ECS). Here we synthesized a series of N-acyl-dopamines (NADAs) and studied their effects on the anandamide membrane transporter, the anandamide amidohydrolase (fatty acid amide hydrolase, FAAH) and the two cannabinoid receptor subtypes, CB(1) and CB(2). NADAs competitively inhibited FAAH from N18TG2 cells (IC(50)=19-100 microM), as well as the binding of the selective CB(1) receptor ligand, [(3)H]SR141716A, to rat brain membranes (K(i)=250-3900 nM). The arachidonoyl (20:4 omega 6), eicosapentaenoyl (20:5 omega 3), docosapentaenoyl (22:5 omega 3), alpha-linolenoyl (18:3 omega 3) and pinolenoyl (5c,9c,12c 18:3 omega 6) homologues were also found to inhibit the anandamide membrane transporter in RBL-2H3 basophilic leukaemia and C6 glioma cells (IC(50)=17.5-33 microM). NADAs did not inhibit the binding of the CB(1)/CB(2) receptor ligand, [(3)H]WIN55,212-2, to rat spleen membranes (K(i)>10 microM). N-arachidonyl-dopamine (AA-DA) exhibited 40-fold selectivity for CB(1) (K(i)=250 nM) over CB(2) receptors, and N-docosapentaenoyl-dopamine exhibited 4-fold selectivity for the anandamide transporter over FAAH. AA-DA (0.1-10 microM) did not displace D1 and D2 dopamine-receptor high-affinity ligands from rat brain membranes, thus suggesting that this compound has little affinity for these receptors. AA-DA was more potent and efficacious than anandamide as a CB(1) agonist, as assessed by measuring the stimulatory effect on intracellular Ca(2+) mobilization in undifferentiated N18TG2 neuroblastoma cells. This effect of AA-DA was counteracted by the CB(1) antagonist SR141716A. AA-DA behaved as a CB(1) agonist in vivo by inducing hypothermia, hypo-locomotion, catalepsy and analgesia in mice (1-10 mg/kg). Finally, AA-DA potently inhibited (IC(50)=0.25 microM) the proliferation of human breast MCF-7 cancer cells, thus behaving like other CB(1) agonists. Also this effect was counteracted by SR141716A but not by the D2 antagonist haloperidol. We conclude that NADAs, and AA-DA in particular, may be novel and useful probes for the study of the ECS.
 ...
PMID:N-acyl-dopamines: novel synthetic CB(1) cannabinoid-receptor ligands and inhibitors of anandamide inactivation with cannabimimetic activity in vitro and in vivo. 1104 39

Autologous stem cell transplantation is used widely after high-dose chemotherapy for treating hematological and other malignancies. Bone marrow harvested for autologous bone marrow transplantation may contain residual malignant cells even when the cancer is judged to be in remission. Attempts to purge marrow of its putative residual malignant cells may delay hemopoietic reconstitution and are of uncertain efficacy. In this report, we demonstrate the possibility of applying hypothermia to autologous stem cell purging. Using clonogenic assay, we compared the surviving fraction of human leukemia (HL60, K562) and human small cell lung cancer (H69) cell lines with that of normal human bone marrow CFU-GM and BFU-E cells after incubation at 4 +/- 0.1 degrees C for 24 and 48 h. Hypothermia decreased the surviving fraction of HL60, H69, and K562 cells. In contrast, the surviving fractions of stem cells were not affected by the temperature shift. The surviving fraction of HL60 cells at 4 degrees C cooling was significantly lower than that at 22 degrees C cooling. These findings suggest that in vitro hypothermia may selectively purge residual malignant cells in stored remission bone marrow and may be applicable before autologous bone marrow transplantation. In addition, the method is very simple and cost effective.
 ...
PMID:Application of hypothermia to autologous stem cell purging. 1157 18

Dietary dehydroepiandrosterone (DHEA) inhibits the proliferation of syngeneic bone marrow cells (BMC) infused into lethally irradiated mice. Potential mechanisms for suppression of hematopoiesis were evaluated and the findings were as follows: (i) depletion of NK, T, B or macrophage cells failed to reverse suppression by DHEA; (ii) stem cell stimulation by erythropoietin, growth hormone, interleukin-2, Friend leukemia virus, or cyclophosphamide failed to reverse suppression; (iii) supplementation of fatty acids, mevalonate, or deoxyribonucleotides, which are dependent upon glucose-6-phosphate dehydrogenase function, did not enhance BMC growth in mice fed DHEA; (iv) DHEA downstream metabolites 4-androstenedione and 17beta-estradiol, as well as the synthetic steroid, 16alpha-chloroepiandrosterone (but not testosterone or 5-androstene-3beta,17beta-diol), also inhibited BMC growth. Tamoxifen antagonized the effects of 17beta-estradiol but not DHEA; (v) dietary DHEA causes hypothermia, but housing of DHEA-fed mice at 34 degrees C to maintain normal body temperature did not reverse suppression; (vi) DHEA leads to a decrease in food intake in rodents. Pair-feeding control diet to mice fed DHEA mimicked the effects of dietary DHEA; (vii) adrenalectomy and orchiectomy decrease the levels of stress and sex hormones, respectively. Neither procedure affected the ability of food restriction or DHEA feeding to inhibit hematopoiesis; (viii) growth of GR-3 NM pre-B leukemia cells in unirradiated mice was also suppressed by DHEA or food restriction. We conclude that DHEA, by reducing food intake in mice, inhibits bone marrow and leukemia cell growth. The precise mechanism(s) by which reduced food intake per se inhibits hematopoiesis is not known, but may involve an increased rate of cellular apoptosis.
 ...
PMID:Dietary dehydroepiandrosterone inhibits bone marrow and leukemia cell transplants: role of food restriction. 1468 46


1 2 Next >>