RESUMO
KH 1060 and CB 966, two novel analogues of 1,25-dihydroxyvitamin D3(1,25(OH)2D3), were found to significantly delay the rejection of allogeneic skin grafts in CBA (H-2k) recipient mice, transplanted with skin from C57Bl/6 (H-2b) donor mice. Graft survival was assessed in mice treated with KH 1060 or CB 966 until the day of rejection, in comparison to mice treated with vehicle, 1,25(OH)2D3 or cyclosporin A (CsA). The mean graft survival time in days was found to be: 16.6 +/- 0.5 (CsA, 20 mg/kg/day orally (p.o.); 13.9 +/- 0.6 and 15.5 +/- 0.6 (1,25(OH)2D3, 0.2 and 0.4 microgram/kg/day intraperitoneally (i.p.)); 14.3 +/- 0.2 and 18.7 +/- 0.5 (CB 966, 0.2 and 0.4 microgram/kg/day i.p.); 13.7 +/- 0.8, 15.7 +/- 1.7, 18.2 +/- 2.7 and 24.5 +/- 0.5 (KH 1060, 0.02, 0.1, 0.2 and 0.4 microgram/kg/day i.p.). Mean graft survival in days for control mice was: 10.3 +/- 0.2 (vehicle for injection, i.p.) and 11.5 +/- 0.2 (olive oil, p.o.). Serum calcium levels, measured on the day of rejection, rose moderately after treatment with either KH 1060 or CB 966. Combination of CsA (20 mg/kg/day p.o.) with KH 1060 (0.1 microgram/kg/day i.p.) resulted in an additive or synergistic effect: 23.4 +/- 1.1 days of skin allograft survival, compared to 15.7 +/- 1.7 days with KH 1060 alone, and 15.1 +/- 1.9 days with CsA alone. KH 1060 was the most active of the tested compounds and can therefore be regarded as a potent immunosuppressor in transplantation; it can be used in combination with CsA and is effective at doses which only marginally affect serum calcium levels.
Assuntos
Calcitriol/análogos & derivados , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/farmacologia , Transplante de Pele/imunologia , Animais , Calcitriol/administração & dosagem , Calcitriol/farmacologia , Ciclosporina/administração & dosagem , Ciclosporina/farmacologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Antígenos H-2 , Imunossupressores/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Transplante HomólogoRESUMO
Seventeen patients (9 men, 8 women; aged 27 to 75 years) who were on chronic hemodialysis for 1 to 14 years were included in the study because they had severe hyperparathyroidism diagnosed by elevated plasma alkaline phosphatase and on plasma intact PTH levels more than twice the upper limit of normal. They had been previously treated with various combinations of oral calcium and/or Al(OH)3 as phosphate binders, oral 1 alpha(OH) vitamin D3 metabolites and a dialysate calcium concentration (DCa) of 1.6 to 1.75 mmol/liter. When i.v. alpha calcidol was introduced DCa was reduced to 1.25 mmol/liter and CaCO3 taken with the meal was used as the sole phosphate binder. alpha calcidol was i.v. injected after the third dialysis of the week at a dose up to 4 micrograms per dialysis in order to obtain a predialysis plasma concentration of Ca at 2.5 +/- 0.2 and PO4 between 1.5 and 2 mmol/liter. All the other treatments were discontinued. During the six months of follow-up, the mean weekly dose of alpha calcidol was 6 micrograms and CaCO3 700 +/- 50 mmol. Plasma calcium (PCa) increased moderately from 2.35 to 2.47 mmol/liter (P < 0.05) whereas plasma PO4 (PPO4) did not significantly increase (1.56/1.64 mmol/liter). Total alkaline phosphatase and its bone isoenzyme activity decreased significantly to normal values [respectively from 186 to 83 IU (normal: 135) and from 102 to 32 IU (normal < 33)] whereas plasma intact PTH decreased from 485 to 125 pg/ml (normal < 55).(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Carbonato de Cálcio/uso terapêutico , Cálcio/sangue , Hidroxicolecalciferóis/uso terapêutico , Hiperparatireoidismo Secundário/terapia , Diálise Renal/efeitos adversos , Administração Oral , Adulto , Idoso , Cálcio/análise , Carbonato de Cálcio/administração & dosagem , Soluções para Diálise/química , Feminino , Humanos , Hidroxicolecalciferóis/administração & dosagem , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Fosfatos/sangueRESUMO
A single blind placebo controlled, cross-over study comparing a new microencapsulated potassium chloride tablet (MET) with two reference formulations of oral potassium, potassium chloride solution (PS) and potassium chloride wax-matrix tablets (WMT), was performed in 12 normal healthy volunteers. Urinary potassium excretion was the main criterion of comparison. Results showed that all three formulations have excellent bioavailability. This indicates that potassium absorption in the stomach is similar to that in more distant portions of the gut. The slow-release characteristics of both MET and WMT were confirmed. Clinical and pharmacological tolerance was excellent and no side-effects were reported with any of the potassium formulations studied.
Assuntos
Cloreto de Potássio/farmacocinética , Potássio/farmacocinética , Administração Oral , Adulto , Idoso , Disponibilidade Biológica , Preparações de Ação Retardada , Composição de Medicamentos , Mucosa Gástrica/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Potássio/urina , Cloreto de Potássio/administração & dosagem , Método Simples-CegoRESUMO
A single blind cross-over study was performed comparing a new microencapsulated potassium chloride tablet (MET) with two reference formulations of oral potassium, namely potassium chloride solution (PS), and microencapsulated potassium chloride capsules (MEC), in 18 normal healthy volunteers. The potassium chloride induced change in gastric potential difference (PD) of the mucosa was the main criterion of comparison and was assessed by the area above curve (AAC), the total duration of the effect (TDE), the maximal variation of PD (delta MAX), and the aggression index (AI). The results showed that all three formulations induced a fall in PD; the delta MAX and AAC were significantly greater for PS indicating a higher aggressive effect of the solution; MET had significantly less aggressive effect than MEC when assessed by all parameters.
Assuntos
Cloreto de Potássio/administração & dosagem , Cloreto de Potássio/farmacocinética , Adulto , Cápsulas , Estudos Cross-Over , Eletrofisiologia , Feminino , Mucosa Gástrica/efeitos dos fármacos , Humanos , Masculino , Método Simples-Cego , SoluçõesAssuntos
Colecalciferol/análogos & derivados , Colecalciferol/farmacologia , Sobrevivência de Enxerto/imunologia , Imunossupressores/farmacologia , Transplante de Pele/imunologia , Animais , Ciclosporina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Transplante HomólogoRESUMO
The French Cancer Plan 2003-2007 has made translational research central to its research programme, to ensure the care-research continuum and the quickest application possible for the most recent discoveries, for the patients' benefit. This is a new field of research, still little-known or ill-understood. A working group, composed of physicians and researchers from academic research and industrial research, sought to define translational research in cancerology and define the issues at stake in it. Translational research needs to develop in close connection with the patients in order to enable a bi-directional flow of knowledge from cognitive research toward medical applications and from observations made on patients toward cognitive research. Placed under the aegis of the French National Cancer Institute and Leem Research, the group has put forth a strategy for implementing translational research in cancerology in France to make it attractive, competitive and efficient and to foster the development of public-private partnerships.
Assuntos
Pesquisa Biomédica/organização & administração , Difusão de Inovações , Neoplasias/terapia , Pesquisa Biomédica/normas , França , Humanos , Comunicação Interdisciplinar , Modelos Animais , Neoplasias/genética , Participação do Paciente/métodosRESUMO
Nitulamide (ANANDRON (R] is an antiandrogen used as an adjuvant therapy in the treatment of advanced prostatic cancer. The effects of ingestion of high doses of nitulamide has not been so far reported. A 79 years old man was admitted 2 hours after the ingestion of 13 g of nitulamide (170 mg/kg or 43 times the therapeutic dose), in a suicide attempt. He was receiving nitulamide 300 mg/day for two weeks. On admission, he underwent immediately gastric lavage, followed by administration of oral activated charcoal and received an intravenous infusion of glucose in balanced salt solution. During the first 12 hours, the patient presented with moderate vomiting and diarrhoea. There was no change in the following parameters: blood cell count, plasma electrolytes, serum transaminases and serum bilirubin, arterial blood gases, plasma cortisol value, as compared to the pre-treatment values. Chest X ray was unchanged. Plasma concentrations were measured 2 hours, 3 hours, 12 hours, 24 hours, 48 hours and 72 hours after ingestion. The initial level reached 6 times the normal therapeutic range, then fell to 3.5 times at the 72th hour. The patient recovered rapidly and was discharged on the 4th day. Biologic parameters were controlled on 4th, 9th, 30th day and remained unchanged. Treatment was started again on the 30th day with nitulamide 150 mg/day. We did not notice any side effect previously described in daily administration of nitulamide: anemia, rise in serum transaminases, interstitial pneumopathy.
Assuntos
Antagonistas de Androgênios/intoxicação , Imidazóis/intoxicação , Imidazolidinas , Idoso , Antagonistas de Androgênios/farmacocinética , Humanos , Imidazóis/farmacocinética , Masculino , SuicídioRESUMO
The solubilized ("cytosolic") receptor present in the rabbit uterus in the absence of hormone and the chromatin-bound ("nuclear") receptor obtained after injection of a progestin were compared. Crude cellular extracts were analyzed by immunoblotting and receptors were purified by immunoaffinity chromatography. With both methods it was observed that the electrophoretic mobility of the "nuclear" receptor was slower than that of the "cytosolic" receptor. This difference in mobility appeared to be due to the existence of variably phosphorylated forms of receptor. The phosphorylation reaction was examined in uterine slices. In the absence of hormone the cytosolic receptor was phosphorylated. When hormone was added the phosphorylation of receptor was markedly enhanced and the electrophoretic mobility of the "nuclear" receptor was decreased. These experiments thus show that the receptor in its "cytosolic" form is a phosphoprotein. Under the effect of the hormone the receptor is further phosphorylated on some supplementary site(s). This polyphosphoprotein is the chromatin-bound, putatively active, form of the receptor. In this respect the intracellular progesterone receptor is similar to various membrane receptors for hormones and growth factors which are phosphorylated upon binding of their ligand.
Assuntos
Núcleo Celular/metabolismo , Norpregnadienos/farmacologia , Fosfoproteínas/metabolismo , Promegestona/farmacologia , Receptores de Progesterona/metabolismo , Útero/metabolismo , Animais , Cromatografia de Afinidade , Citosol/metabolismo , Eletroforese em Gel de Poliacrilamida , Feminino , Peso Molecular , Fosforilação , Coelhos , Receptores de Progesterona/efeitos dos fármacosRESUMO
1,25-Dihydroxyvitamin D3 (1,25(OH)2D3; calcitriol) is the biologically active form of vitamin D. This hormone is a potent immunoregulatory agent. Calcipotriol is a synthetic analogue of 1,25(OH)2D3, with similar receptor binding, and comparable effects on cell proliferation and differentiation, but less potent effects on calcium metabolism. As a step towards understanding the mechanisms by which vitamin D compounds affect T-cell activation by epidermal cells (EC), we assessed the effects of 1,25(OH)2D3 and calcipotriol on the human allogeneic mixed epidermal cell-lymphocyte reaction. All experiments were performed both with 1,25(OH)2D3, and calcipotriol, with similar results. Both compounds had potent immunoinhibitory properties on this model, and enhanced the immunosuppressive effects of cyclosporin A. Using preincubation experiments, we found that pretreatment of EC with 1,25(OH)2D3 resulted in a more pronounced inhibition than preincubation of lymphoid cells. The epidermal targets of this inhibitory effect have been further investigated, using cultures with freshly isolated Langerhans cells (LC) or LC-depleted keratinocytes, separated by an immunomagnetic particle technique. Pretreatment of LC induced a 30% decrease of proliferation, compared with vehicle-treated LC. These calcitriol-pulsed LC did not decrease the proliferation induced by unmodified autologous EC. As expected, LC-depleted keratinocytes failed to stimulate allogenic lymphocytes. When added to autologous unmodified EC, however, calcitriol-pulsed keratinocytes induced an 85% decrease of proliferation, compared with vehicle-treated keratinocytes. The phenotypic expression of HLA-DR, -DQ, and -DP antigens on EC, assessed by immunoalkaline phosphatase staining, was not modified after a 2-h or 24-h pulse with 1,25(OH)2D3 or calcipotriol.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Calcitriol/farmacologia , Epiderme/efeitos dos fármacos , Tolerância Imunológica/efeitos dos fármacos , Calcitriol/análogos & derivados , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta Imunológica , Epiderme/imunologia , Feminino , Antígenos HLA-D/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Células de Langerhans/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/imunologia , Fator de Crescimento Transformador beta/imunologiaRESUMO
A very high capacity immunoaffinity matrix for the purification of progesterone receptor was prepared by cross-linking a monoclonal antireceptor antibody to protein A-Sepharose through the Fc fragment. The monoclonal antibody was selected for its property of losing affinity for the receptor at pH 10.5, i.e., in conditions where the receptor remains stable for extensive periods of time. This made it possible to elute active receptor form the immunosorbent. From crude rabbit uterine cytosol the steroid-receptor complexes were purified in a single step. A 1-mL column (containing 7 mg of monoclonal antibody) bound 1600 pmol of steroid-receptor complexes of which 79.5% were eluted. The overall yield of purification was 49%. The specific activity of the purified steroid-receptor complexes was 6.71 +/- 0.79 nmol of bound steroid/mg of protein (mean +/- SE of four experiments). The purified receptor consisted of a mixture of 110 000- and 79 000-dalton forms. The latter appeared to be produced by proteolysis of the larger form during purification since immunoblot experiments showed that, at the start of purification, the 110 000-dalton form was present in overwhelming majority (80-95%) in the uterine cytosol and that the 79 000-dalton form only appeared during purification. This conclusion was also supported by the peptide analysis of both forms of receptor: the purified receptor was denatured and labeled with 125I; the 110 000- and 79 000-dalton forms were isolated by gel electrophoresis in denaturing conditions and electroelution and were then submitted to mild or extensive digestions by trypsin, chymotrypsin, and protease V8 from Staphylococcus aureus.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Receptores de Progesterona/isolamento & purificação , Animais , Anticorpos Monoclonais , Cromatografia de Afinidade , Citosol/metabolismo , Feminino , Cinética , Substâncias Macromoleculares , Peso Molecular , Fragmentos de Peptídeos/análise , Promegestona/metabolismo , Coelhos , Receptores de Progesterona/imunologia , Receptores de Progesterona/metabolismo , Sefarose , Proteína Estafilocócica A , Útero/metabolismoRESUMO
We report that calcipotriol (CPT) is a potent inhibitor of lymphocyte proliferation in mixed epidermal cell lymphocyte reactions. In this model, CPT and cyclosporine A (CsA) have synergistic effects. These results have led to a randomised double-blind therapeutic study protocol in patients with severe psoriasis. In these patients, topical CPT and sub-therapeutic doses of CsA (2mg/kg/d) induce disappearance of cutaneous lesions. This therapeutic association may minimize secondary side effects of both drugs.
Assuntos
Calcitriol/análogos & derivados , Ciclosporina/uso terapêutico , Fármacos Dermatológicos/farmacologia , Fármacos Dermatológicos/uso terapêutico , Psoríase/tratamento farmacológico , Adulto , Calcitriol/administração & dosagem , Calcitriol/farmacologia , Calcitriol/uso terapêutico , Divisão Celular/efeitos dos fármacos , Doença Crônica , Ciclosporina/farmacologia , Fármacos Dermatológicos/administração & dosagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Sinergismo Farmacológico , Feminino , Humanos , Técnicas In Vitro , Teste de Cultura Mista de Linfócitos , Linfócitos/citologia , MasculinoRESUMO
Vitamin D insufficiency and low calcium intake contribute to increase parathyroid function and bone fragility in elderly people. Calcium and vitamin D supplements can reverse secondary hyperparathyroidism thus preventing hip fractures, as proved by Decalyos I. Decalyos II is a 2-year, multicenter, randomized, double-masked, placebo-controlled confirmatory study. The intention-to-treat population consisted of 583 ambulatory institutionalized women (mean age 85.2 years, SD = 7.1) randomized to the calcium-vitamin D3 fixed combination group (n = 199); the calcium plus vitamin D3 separate combination group (n = 190) and the placebo group (n = 194). Fixed and separate combination groups received the same daily amount of calcium (1200 mg) and vitamin D3 (800 IU), which had similar pharmacodynamic effects. Both types of calcium-vitamin D3 regimens increased serum 25-hydroxyvitamin D and decreased serum intact parathyroid hormone to a similar extent, with levels returning within the normal range after 6 months. In a subgroup of 114 patients, femoral neck bone mineral density (BMD) decreased in the placebo group (mean = -2.36% per year, SD = 4.92), while remaining unchanged in women treated with calcium-vitamin D3 (mean = 0.29% per year, SD = 8.63). The difference between the two groups was 2.65% (95% CI = -0.44, 5.75%) with a trend in favor of the active treatment group. No significant difference between groups was found for changes in distal radius BMD and quantitative ultrasonic parameters at the os calcis. The relative risk (RR) of HF in the placebo group compared with the active treatment group was 1.69 (95% CI = 0.96, 3.0), which is similar to that found in Decalyos I (RR = 1.7; 95% CI = 1.0, 2.8). Thus, these data are in agreement with those of Decalyos I and indicate that calcium and vitamin D3 in combination reverse senile secondary hyperparathyroidism and reduce both hip bone loss and the risk of hip fracture in elderly institutionalized women.