RESUMO
Leucovorin enhances the cytotoxicity of fluorouracil (5-FU) in patients with colorectal cancer and may increase the efficacy of combination chemotherapy regimens containing 5-FU. To determine the maximum tolerated dose of 5-FU with leucovorin for use in combination with cyclophosphamide and doxorubicin, we conducted a phase I/II trial in 20 patients. The doses of leucovorin (200 mg/m2 on days 1-5), cyclophosphamide (500 mg/m2 on day 1), and doxorubicin (40 mg/m2 on day 1) were held constant, while the dose of 5-FU was escalated in cohorts of patients beginning at 150 mg/m2 on days 1-5. Cycles were repeated every 3 weeks. Significant mucositis, diarrhea, and myelosuppression were infrequently observed in patients receiving up to 250 mg/m2 5-FU on days 1-5. In contrast, at a dose of 300 mg/m2 on days 1-5, three of six patients had granulocyte count nadirs of less than 500/microL during the first cycle of therapy, and two of these three had platelet counts of less than 25,000/microL. In addition, two patients treated at this dose had significant mucosal toxic effects, and three had insufficient recovery to permit a second course by day 22. Among 14 patients with assessable breast cancer, there were one complete and nine partial responses (response rate 71%). Leucovorin modulation of 5-FU can be safely incorporated into combination chemotherapy with cyclophosphamide and doxorubicin and provides a highly active regimen for treatment of metastatic breast cancer. Further study will be required to determine whether the addition of leucovorin significantly enhances the activity of this regimen.
Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/secundário , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Avaliação de Medicamentos , Feminino , Fluoruracila/administração & dosagem , Humanos , Infusões Intravenosas , Injeções Intravenosas , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-IdadeRESUMO
PURPOSE: To determine whether biochemical modulation with LV (leucovorin) enhances the efficacy of CAF (cyclophosphamide, doxorubicin, and fluorouracil) against metastatic breast cancer. PATIENTS AND METHODS: Women with histologically confirmed stage IV breast cancer, Cancer and Leukemia Group B (CALGB) performance status 0 to 2, and no prior chemotherapy for metastatic disease were randomly assigned to receive CAF (cyclophosphamide 500 mg/m2 day 1, doxorubicin 40 mg/m2 day 1, and fluorouracil [FU] 200 mg/m2 intravenous bolus days 1 to 5) with or without LV (LV 200 mg/m2 over 30 minutes days 1 to 5 given 1 hour before FU). RESULTS: Two hundred forty-two patients were randomly assigned to treatment; 124 patients had visceral crisis and 40 patients had a CALGB performance status score of 2. The median follow-up was 6 years. The two study arms were similar with regard to serious adverse events; four patients died from treatment-related causes, two patients on each study arm. Predictive variables for time to treatment failure and survival were visceral disease and performance status. The overall response rate was 29% for CAF versus 28% for CAF plus LV. The median time to treatment failure (9 months) and median survival (1.7 years) did not differ by treatment arm. CONCLUSION: Modulation of CAF with LV improved neither response rates nor survival among women with metastatic breast cancer, compared with CAF alone. Multivariate analyses confirmed the prognostic importance of performance status and visceral crisis. However, the overall and complete response rates, response durations, time to treatment failure, and survival were the same in the two treatment arms.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Progressão da Doença , Doxorrubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Nível de Saúde , Humanos , Leucovorina/administração & dosagem , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Sobrevida , Resultado do Tratamento , Vísceras/patologiaRESUMO
BACKGROUND: Biopsies performed for elevated serum PSA often show inflammatory infiltrates. However, the influence of intraprostatic inflammation on serum PSA in men without biopsy indication and negative for prostate cancer has not been described in detail. METHODS: We studied 224 men in the placebo arm of the Prostate Cancer Prevention Trial (PCPT) who underwent end-of-study biopsy per trial protocol, had PSA <4 ng ml(-1), normal digital rectal examination and a biopsy negative for cancer. We analyzed data from hematoxylin and eosin-stained slides containing a mean of three biopsy cores. Inflammation measures included the extent (percentage of tissue area with inflammation) and intensity (product of scores for extent and grade) of total, acute and chronic inflammation in the entire tissue area examined, and by tissue compartment. We calculated median measures of inflammation by prebiopsy serum PSA tertile (>0 to ≤0.8, >0.8 to ≤1.5 and >1.5 to <4.0 ng ml(-1)). We estimated the association between percentage of tissue area with inflammation and natural logarithm of PSA using linear regression adjusting for age at biopsy. RESULTS: Median percentage of tissue area with inflammation increased from 2 to 5 to 9.5% across PSA tertiles (P-trend <0.0001). For every 5% increase in tissue area with inflammation, log PSA increased by 0.061 ng ml(-1) (P=0.0002). Median extent and intensity scores increased across PSA tertiles in luminal and intraepithelial compartments for acute inflammation and in stromal and intraepithelial compartments for chronic inflammation (all P-trend ≤0.05). CONCLUSIONS: In men without clinical suspicion of prostate cancer, greater overall inflammation, luminal and intraepithelial acute inflammation and stromal and intraepithelial chronic inflammation were associated with higher serum PSA.
Assuntos
Inflamação/patologia , Antígeno Prostático Específico/sangue , Próstata/patologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Biópsia , Estudos de Casos e Controles , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
There is dramatic international variation in prostate cancer mortality rates. The variation suggests that the disease has an environmental cause and encourages the search for a way to prevent it. Androgenic stimulation over a period of time, perhaps due to a high fat diet, has been suggested as a cause of prostate cancer. The corollary to this hypothesis is that lowering androgenic stimulation over time will prevent prostate cancer. 5-Alpha-reductase inhibition through drugs like finasteride have been shown to decrease androgenic stimulation of the prostate. A clinical trial is underway using finasteride to assess this hypothesis. Epidemiological and laboratory studies also suggest that those with high selenium and vitamin E intake have a lower risk of prostate cancer. Recent serendipitous findings of two randomised clinical trials support this. A study to assess these compounds is currently being designed. Other promising but less developed interventions in the chemoprevention of prostate cancer include vitamin D supplementation and diet modification.
Assuntos
Inibidores Enzimáticos/uso terapêutico , Finasterida/uso terapêutico , Neoplasias da Próstata/prevenção & controle , Selênio/uso terapêutico , Vitamina E/uso terapêutico , Inibidores de 5-alfa Redutase , Idoso , Animais , Ensaios Clínicos como Assunto , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/tratamento farmacológico , Coelhos , Fatores de RiscoRESUMO
Progestins at standard doses have compared favorably with tamoxifen for the front-line treatment of women with metastatic breast cancer. Attempts to further enhance the role of progestins have centered on dosage escalation, based on European data suggesting a dose-response effect. A phase I/II pilot trial at the University of Maryland demonstrated that doses of megestrol acetate up to 1,600 mg/d were well tolerated for prolonged periods. Responses were seen in patients whose disease was refractory to both standard doses of megestrol acetate and to tamoxifen. Different mechanisms of progestin action on breast tumors are theorized at the higher doses, which could account for the dose-response effect. Two large multi-institutional dose comparison trials of megestrol acetate in metastatic breast cancer have been undertaken in the United States. The Piedmont Oncology Association recently reported a significant benefit for megestrol acetate 800 mg/d compared with the standard 160 mg/d in terms of response and disease-free and overall survival. The largest trial is currently ongoing in the Cancer and Leukemia Group B. They are comparing 800 and 1,600 mg/d with standard doses, and results from this study are eagerly anticipated.
Assuntos
Neoplasias da Mama/tratamento farmacológico , Congêneres da Progesterona/administração & dosagem , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Feminino , Humanos , Medroxiprogesterona/administração & dosagem , Medroxiprogesterona/análogos & derivados , Medroxiprogesterona/uso terapêutico , Acetato de Medroxiprogesterona , Megestrol/administração & dosagem , Megestrol/efeitos adversos , Megestrol/análogos & derivados , Megestrol/uso terapêutico , Acetato de Megestrol , Congêneres da Progesterona/uso terapêuticoRESUMO
Cachexia can be a severe problem in the management of patients with cancer and other illnesses because it produces an ever-increasing spiral of anorexia, undernutrition, loss of tissue mass, muscle wasting, and increased susceptibility to infection and treatment toxicity. Megestrol acetate has been observed to produce weight gain in patients with hormone-sensitive tumors and has recently been noted to produce a similar degree of weight gain in those with hormone insensitive tumors. A review of our experience in a phase I-II study of escalating doses of megestrol acetate for advanced breast cancer revealed that weight gain occurred in more than 80% of all treated patients and in 90% of those patients who received treatment for 6 or more weeks. The median maximum weight gain was 5.5 kg, with a range of -5.6 to 44 kg. Subjective improvement in appetite occurred in most patients. These data provided the impetus for a series of further studies of the role of megestrol acetate in the control of cachexia, including a randomized study in cancer cachexia, AIDS cachexia, and anorexia nervosa. In addition, a number of laboratory trials seeking the mechanism of action have been initiated, as well as whole-animal studies to define the compartment of increased weight. Our data and the preliminary observation of weight gain in patients with hormone insensitive tumors suggest that megestrol acetate has a potential role in producing a possibly dose-related subjective improvement and an increase in appetite and weight. Further research is necessary to understand the mechanism of appetite stimulation and anabolic effect.
Assuntos
Neoplasias da Mama/complicações , Caquexia/tratamento farmacológico , Megestrol/análogos & derivados , Peso Corporal , Neoplasias da Mama/tratamento farmacológico , Caquexia/etiologia , Avaliação de Medicamentos , Feminino , Humanos , Megestrol/administração & dosagem , Megestrol/uso terapêutico , Acetato de MegestrolRESUMO
The extreme anorexia and cachexia associated with cancer and other disease states often have important physical and psychologic impact on both patients and their families. Weight gain resulting from megestrol acetate therapy in breast cancer patients suggests that progestins may be useful for alleviation of disease-associated appetite and weight loss. Early breast cancer experience, as well as preliminary data from a randomized, placebo-controlled trial of high-dose megestrol acetate in cancer anorexia and wasting, is therefore reviewed. Although the precise mechanism by which megestrol acetate exerts its effect remains unclear, weight gain was observed in 75% of patients in the high-dose study and in nearly all of those who remained on therapy for 6 weeks. It was concluded that, although megestrol acetate cannot be expected to directly affect the prognosis of patients with hormone-insensitive tumors, it may increase host resistance by improving nutritional status and/or enhancing the quality of life.
Assuntos
Anorexia/tratamento farmacológico , Apetite/efeitos dos fármacos , Megestrol/análogos & derivados , Aumento de Peso/efeitos dos fármacos , Adulto , Idoso , Anorexia/etiologia , Feminino , Humanos , Masculino , Megestrol/uso terapêutico , Acetato de Megestrol , Pessoa de Meia-Idade , Neoplasias/complicaçõesRESUMO
We recently observed significant weight gain in patients with advanced breast cancer treated with high-dose megestrol acetate. However, the mechanisms of this effect are completely unknown. As the analysis of the action of steroids in vivo is complex, we chose to examine the effects of megestrol acetate on the differentiation of a preadipocyte clone (L1) of the Swiss 3T3 mouse fibroblast cell line. Addition of insulin, fetal bovine serum, dexamethasone, and methyl-isobutylxanthine to confluent 3T3-L1 cells induced adipocyte differentiation, as verified by morphologic studies and analysis of the activity of the enzyme glycerol-3-phosphate dehydrogenase (G-3-PD), a specific and sensitive indicator of lipocyte function. Substitution of megestrol acetate for dexamethasone also resulted in greatly increased lipocyte differentiation. Tumor necrosis factor (TNF) alpha blocked the adipocyte differentiation induced by the combination of insulin, dexamethasone, and methyl-isobutylxanthine. Addition of megestrol acetate failed to reverse the inhibitory effect of TNF. Thus, megestrol acetate, in vitro, is a potent inducer of lipocyte differentiation. Further studies on the regulation of adipocyte differentiation and function in this model system may be important to clarify megestrol acetate's mechanism of action.
Assuntos
Tecido Adiposo/citologia , Megestrol/análogos & derivados , 1-Metil-3-Isobutilxantina/farmacologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/enzimologia , Animais , Bovinos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Dexametasona/farmacologia , Sangue Fetal , Glicerolfosfato Desidrogenase/metabolismo , Insulina/farmacologia , Megestrol/farmacologia , Acetato de Megestrol , Camundongos , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
1. The distribution, pharmacology and effects of neurodegenerative diseases on 5-HT4 receptors in human brain have been characterized in vitro. 2. The 5-HT4 receptor in post mortem human brain tissue was specifically labelled with [3H]-GR 113808. In human putamen, this ligand labelled a homogeneous population of sites, with an apparent affinity (-log Kd) of 10.1 and a density (Bmax) of 5.73 fmol mg-1 tissue. The pharmacology of this site was characterized by use of a series of displacing ligands, and the following rank order of apparent affinities (with mean +/- s.d. -log Ki values in parentheses) was generated: GR113808 (10.05 +/- 0.04) > SDZ 205,557 (8.65 +/- 0.08) > DAU 6285 (7.95 +/- 0.04) > BIMU-1 (7.81 +/- 0.06) > DAU 6215 (7.42 +/- 0.23) > tropisetron (7.39 +/- 0.23) > 5-HT (7.32 +/- 1.00) > BIMU-8 (7.25 +/- 0.04) > (R)-zacopride (5.82 +/- 0.04). The Hill coefficients were not significantly different from unity, consistent with an interaction at a single site. A comparison of the affinities of these compounds with those obtained from guinea-pig striatum indicated no evidence of species differences. 3. The regional distribution of 5-HT4 receptors was assessed by determining the density of binding sites for [3H]-GR 113808. The distribution were as follows (with mean +/- s.d. Bmax values, fmol mg-1 tissue, in parentheses): caudate nucleus (8.7 +/- 1.5), lateral pallidum (8.6 +/- 5.5), putamen (5.7 +/- 3.0), medial pallidum (3.8 +/- 0.9), temporal cortex (2.6 +/- 0.6), hippocampus (2.4 +/- 0.8), amygdala (2.3 +/-1.1), frontal cortex (1.7 +/- 0.5), cerebellar cortex (<1.0). In these studies, the affinities of GR 113808 were not significantly different.4. The density of 5-HT4 receptors selected from regions of post mortem brains of patients with Parkinson's disease, Huntington's disease and Alzheimer's disease were compared to age-matched controls. In Parkinson's disease, there was no significant difference between control or patient values(mean +/- s.d. Bmax values, fmol mg-1 tissue; putamen, control 4.74 +/- 0.07, patient 5.86 +/- 1.48; substantia nigra, control 4.21 +/- 2.56, patient 5.57 +/- 0.10). In Huntington's disease, there was a significant decrease in putamen (control 5.33 +/- 1.08, patient 2.68 +/- 1.08), while in Alzheimer's disease, there was a marked loss of receptors in hippocampus (control 2.34 +/- 0.62, patient 0.78 +/- 0.61), in frontal cortex (control,1.76 +/- 0.19, patient 1.30 +/- 0.22). Receptor density in temporal cortex showed a decrease, but did not achieve statistical significance (control 2.06 +/- 0.21, patient 1.44 +/- 0.64).5. These data suggest a heterogeneous distribution of 5-HT4 receptors in human brain, with high to moderate densities in basal ganglia and limbic structures. These receptors may not be principally co-localized on dopaminergic cell bodies or terminals, given the lack of change observed in Parkinson's disease. The loss of 5-HT4 receptors in the putamen in Huntington's disease raises the possibility of their presence on intrinsic striatal GABAergic or cholinergic neurones. The marked loss of receptors in hippocampal and cortical regions in the brains from patients with Alzheimer's disease is consistent with a role for the 5-HT4 receptor in cognitive processing.
Assuntos
Química Encefálica/fisiologia , Degeneração Neural , Doenças do Sistema Nervoso/metabolismo , Receptores de Serotonina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Ligação Competitiva/efeitos dos fármacos , Química Encefálica/efeitos dos fármacos , Feminino , Cobaias , Humanos , Técnicas In Vitro , Indóis/metabolismo , Cinética , Masculino , Pessoa de Meia-Idade , Ensaio Radioligante , Receptores Muscarínicos/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Antagonistas da Serotonina/metabolismo , Sulfonamidas/metabolismoRESUMO
1. A series of isoquinolines have been identified as 5-HT3 receptor antagonists. One of these, RS 25259-197 [(3aS)-2-[(S)-1-azabicyclo[2.2.2]oct-3-yl]-2,3,3a,4,5,6-hexahydro- 1- oxo-1H-benzo[de]isoquinoline-hydrochloride], has two chiral centres. The remaining three enantiomers are denoted as RS 25259-198 (R,R), RS 25233-197 (S,R) and RS 25233-198 (R,S). 2. At 5-HT3 receptors mediating contraction of guinea-pig isolated ileum, RS 25259-197 antagonized contractile responses to 5-HT in an unsurmountable fashion and the apparent affinity (pKB), estimated at 10 nM, was 8.8 +/- 0.2. In this tissue, the -log KB values for the other three enantiomers were 6.7 +/- 0.3 (R,R), 6.7 +/- 0.1 (S,R) and 7.4 +/- 0.1 (R,S), respectively. The apparent affinities of RS 25259-197 and RS 25259-198, RS 25233-197 and RS 25233-198 at 5-HT3 receptors in membranes from NG-108-15 cells were evaluated by a [3H]-quipazine binding assay. The -log Ki values were 10.5 +/- 0.2, 8.4 +/- 0.1, 8.6 +/- 0.1 and 9.5 +/- 0.1, respectively, with Hill coefficients not significantly different from unity. Thus, at these 5-HT3 receptors, the rank order of apparent affinities was (S,S) > (R,S) > (S,R) = (R,R). 3. RS 25259-197 displaced the binding of the selective 5-HT3 receptor ligand, [3H]-RS 42358-197, in membranes from NG-108-15 cells, rat cerebral cortex, rabbit ileal myenteric plexus and guinea-pig ileal myenteric plexus, with affinity (pKi) values of 10.1 +/- 0.1, 10.2 +/- 0.1, 10.1 +/- 0.1 and 8.3 +/- 0.2, respectively. In contrast, it exhibited low affinity (pKi <6.0) at 28 other receptors in binding assays, including adrenoceptors (alpha1A, alpha 1B, alpha2A, alpha 2B ,beta1, beta2), muscarinic (M1-M4), dopamine (D1, D2), opioid and other 5-HT(5-HTlA, 5-HTlD, 5-HT2C, 5-HT4) receptors.4. RS 25259-197 was tritium labelled (specific activity: 70 Ci mmol-1) and evaluated in pharmacological studies. Saturation studies with [3H]-RS 25259-197 in membranes from NG-108-15 and cloned homomeric a subunits of the 5-HT3 receptor from N1E-1 15 cells expressed in human kidney 293E1 cells,revealed an equilibrium dissociation constant (Kd) of 0.05 +/- 0.02 and 0.07 +/- 0.01 nM, and Bmax of610 +/- 60 and 1068 +/- 88 fmol mg-1, respectively. Competition studies in NG-108-15 cells indicated a pharmacological specificity entirely consistent with labelling a 5-HT3 receptor, i.e. RS 25259-197> granisetron> (S)-zacopride> tropisetron> (R)-zacopride> ondansetron> MDL 72222.5. In contrast to the majority of radioligands available to label 5-HT3 receptors, [3H]-RS 25259-197 labelled a high affinity site in hippocampus from human post-mortem tissue with an equilibrium dissociation constant (Kd) of 0.15 +/- 0.07 nM and density (BmaX) of 6.8 +/- 2.4 fmol mg-1 protein. Competition studies in this tissue indicated a pharmacological specificity consistent with labelling of a 5-HT3receptor.6. Quantitative autoradiographic studies in rat brain indicated a differential distribution of 5-HT3receptor sites by [3H]-RS 25259-197. High densities of sites were seen in nuclear tractus solitaris and area postrema, a medium density in spinal trigeminal tract, ventral dentate gyrus and basal medial amygdala,and a low density of sites in hippocampal CAl, parietal cortex, medium raphe and cerebellum.7 In conclusion, the functional, binding and distribution studies undertaken with the radiolabelled and non-radiolabelled RS 25259-197 (S,S enantiomer) established the profile of a highly potent and selective5-HT3 receptor antagonist.
Assuntos
Encéfalo/efeitos dos fármacos , Íleo/efeitos dos fármacos , Isoquinolinas/farmacologia , Quinuclidinas/farmacologia , Receptores de Serotonina/efeitos dos fármacos , Antagonistas da Serotonina/farmacologia , Animais , Autorradiografia , Ligação Competitiva , Encéfalo/metabolismo , Cobaias , Técnicas In Vitro , Isoquinolinas/metabolismo , Camundongos , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Plexo Mientérico/efeitos dos fármacos , Plexo Mientérico/metabolismo , Palonossetrom , Quinuclidinas/metabolismo , Quipazina/metabolismo , Ensaio Radioligante , Ratos , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/metabolismo , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
The dramatic international variation in prostate cancer mortality rates suggest an environmental influence. This combined with a building understanding of the genetic mechanisms of carcinogenesis encourages a search for ways to prevent it. Androgenic stimulation over a period of time has been suggested a cause of prostate cancer. The corollary to this hypothesis is that lowering androgenic stimulation over time will prevent prostate cancer. Decreasing androgenic stimulation of the prostate with 5-alpha-reductase inhibitors such as finasteride has been shown to decrease prostate size and may prevent prostate cancer. A large, long-term clinical trial is underway using finasteride to determine if it can prevent prostate cancer. Results are expected in 2004. Epidemiologic and laboratory studies also suggest that high selenium and vitamin E intake lowers risk of prostate cancer. Recent serendipitous findings of two randomized clinical trials support the hypothesis that selenium and vitamin administration will decrease prostate cancer risk. A study to assess these compounds is beginning. Other promising, but less developed, interventions in chemoprevention of prostate cancer include vitamin D supplementation and diet modification. All will need to be rigorously evaluated before they can be advocated for prostate cancer prevention.
Assuntos
Adenocarcinoma/prevenção & controle , Androgênios , Neoplasias Hormônio-Dependentes/prevenção & controle , Neoplasias da Próstata/prevenção & controle , Inibidores de 5-alfa Redutase , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adulto , Idoso , Antagonistas de Androgênios/uso terapêutico , Anticarcinógenos/uso terapêutico , Antioxidantes/uso terapêutico , Ensaios Clínicos como Assunto , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Dieta , Método Duplo-Cego , Inibidores Enzimáticos/uso terapêutico , Finasterida/uso terapêutico , Previsões , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Neoplasias Hormônio-Dependentes/genética , Neoplasias Hormônio-Dependentes/mortalidade , Neoplasia Prostática Intraepitelial/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Risco , Selênio/uso terapêutico , Proteínas de Soja/uso terapêutico , Resultado do Tratamento , Vitamina A/uso terapêutico , Vitamina D/uso terapêutico , Vitamina E/uso terapêuticoRESUMO
Anorexia and cachexia frequently complicate the late stages of malignancy and may be a prominent feature of early disease. The resulting weight loss often becomes a major focus of concern for the patient and the family and may significantly add to the morbidity and mortality of cancer. Factors which contribute to the wasting syndrome include the effects of the tumour, effects of chemotherapy, abnormalities of carbohydrate, fat and protein metabolism and the cytokine response. Administration of total parenteral nutrition (TPN) is an important method of addressing malnutrition, particularly in patients with nonfunctioning gastrointestinal tracts. A critical review of the TPN cancer literature is provided along with a discussion of new approaches and future directions in the nutritional support of patients with malignant disease, such as anabolic agents, hydrazine sulfate and megestrol.
Assuntos
Caquexia/etiologia , Neoplasias/complicações , Nutrição Parenteral Total , Desnutrição Proteico-Calórica/terapia , Anorexia/etiologia , Anorexia/terapia , Caquexia/terapia , Terapia Combinada , Hormônios/uso terapêutico , Humanos , Hidrazinas/uso terapêutico , Megestrol/uso terapêutico , Neoplasias/metabolismo , Neoplasias/terapia , Desnutrição Proteico-Calórica/etiologia , Desnutrição Proteico-Calórica/metabolismoRESUMO
To define a maximum tolerable dose, chloroquinoxaline sulfonamide (CQS) was given as a 1-h infusion every 28 days to cancer patients for whom no effective standard therapy was available. Doses were escalated in cohorts of at least three patients each. Plasma for characterization of the pharmacokinetics of free and total CQS was obtained during and after the initial infusion and, when possible, during and after subsequent infusions of CQS if the dose had been reduced. A total of 101 courses of CQS in 55 patients were evaluated. Dose levels ranged from 18 to 3,700 mg/m2. The dose-limiting toxicity was hypoglycemia, first recognized at the 3,700-mg/m2 dose. When dose-limiting hypoglycemia was recognized, patients were entered at successively lower doses, with close monitoring of plasma glucose and insulin concentrations being done in 26 patients. Grade 1-3 hypoglycemia occurred within 4 h of the termination of CQS infusion and cleared by 24 h. Symptomatic hypoglycemia was more frequent at doses of CQS above 1,000 mg/m2. Concomitant administration of 5% glucose did not ameliorate the hypoglycemia associated with CQS doses of > 1,000 mg/m2. The total calorie intake, percentage of ideal body weight, or percentage of weight lost did not explain the incidence or severity of hypoglycemia in 12 patients in whom these data were obtained. Cardiac tachyarrhythmias occurred in 7 patients who received CQS at doses of > or = 1,000 mg/m2, and tachyarrhythmia was associated with hypoglycemia in 3 patients. Other toxicities were sporadic, but the frequency of toxicity was higher at CQS doses of > or = 1,000 mg/m2. These toxicities included fever, rash, lightheadedness, leukopenia, thrombocytopenia, alopecia, diarrhea, nausea, and vomiting. All toxicities were reversible. Mean peak plasma [CQS] and AUC increased with dose, with a suggestion that peak plasma [CQS] plateaued at higher doses. The decline in plasma [CQS] was fitted to a three-compartment, open linear model. The terminal half-life ranged from 28 to 206 h. Total body clearance ranged from 44 to 881 ml/h with no evidence of saturation. Urinary excretion of the parent compound in 24 h averaged < 5%. CQS not bound to plasma protein (free CQS) comprised 1%-17% of total plasma CQS and was not related to dose. A relationship was defined between the magnitude of hypoglycemia and CQS pharmacokinetic parameters. The percentage of decrease in plasma [glucose], i.e., (predose [glucose]-nadir [glucose]/predose [glucose]) x 100, correlated with both free and total peak plasma [CQS].(ABSTRACT TRUNCATED AT 400 WORDS)
Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Quinoxalinas/uso terapêutico , Sulfanilamidas/uso terapêutico , Adulto , Idoso , Peso Corporal , Medula Óssea/efeitos dos fármacos , Feminino , Humanos , Hipoglicemia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Quinoxalinas/efeitos adversos , Quinoxalinas/farmacocinética , Sulfanilamidas/efeitos adversos , Sulfanilamidas/farmacocinéticaRESUMO
CPT-11 is a topoisomerase I inhibitor with activity against colorectal cancer. This study was designed to explore the potential for combining CPT-11 with fluorouracil and leucovorin. 5-FU (500 mg/m(2)) and leucovorin (500 mg/m(2)) were administered for 4 consecutive weeks and CPT-11 was given on weeks 1 and 4 of each 6 week cycle. The starting dose of CPT-11 was 25 mg/m(2) and the dosage was escalated by increments of 25 mg/m(2) in cohorts of 3 patients. Nine patients were treated on study. Grade 4 diarrhea was the dose limiting toxicity at 50 mg/m(2). Alternative strategies to combine CPT-11 with 5-FU and leucovorin are being explored.
RESUMO
A high jugular bulb is often discovered as an incidental finding that is asymptomatic. Conductive hearing loss in association with this anomaly may occur, but has been reported infrequently in the literature. We report five cases of high jugular bulb and associated conductive hearing loss. Mechanisms to explain the conductive hearing loss include contact of the jugular bulb with the tympanic membrane, interference with the ossicular chain, and obstruction of the round window niche. The operative findings, radiographic and audiometric data that support these mechanisms of conductive hearing loss are presented.
Assuntos
Perda Auditiva Condutiva/etiologia , Veias Jugulares/anormalidades , Testes de Impedância Acústica , Adulto , Criança , Colesteatoma da Orelha Média/diagnóstico , Diagnóstico Diferencial , Ossículos da Orelha/patologia , Feminino , Perda Auditiva Condutiva/diagnóstico por imagem , Perda Auditiva Condutiva/cirurgia , Humanos , Veias Jugulares/diagnóstico por imagem , Veias Jugulares/patologia , Veias Jugulares/cirurgia , Angiografia por Ressonância Magnética , Masculino , Janela da Cóclea/patologia , Tomografia Computadorizada por Raios X , Membrana Timpânica/patologiaAssuntos
Histamina/análise , Mastócitos/análise , Difusão , Liofilização , Histocitoquímica , Métodos , Microscopia de Fluorescência , Microtomia , Modelos QuímicosAssuntos
Neoplasias da Mama/tratamento farmacológico , Caquexia/tratamento farmacológico , Megestrol/análogos & derivados , Neoplasias da Mama/complicações , Caquexia/etiologia , Avaliação de Medicamentos , Feminino , Humanos , Megestrol/administração & dosagem , Megestrol/efeitos adversos , Megestrol/uso terapêutico , Acetato de Megestrol , Aumento de Peso/efeitos dos fármacosRESUMO
Using data from the National Longitudinal Surveys (NLS) of Older Men, this study examined the extent and character of the work experience of men who opt to continue labor force participation well beyond conventional retirement age. Logistic regression results showed that good health, a strong psychological commitment to work, and a corresponding distaste for retirement are among the most important characteristics related to continued employment into old age. The probability of employment was also found to be positively related to educational attainment and being married to a working wife; it was negatively related to age and level of income in the absence of work. Of the men in the sample who were not working, very few gave evidence of a desire to do so. Policy implications of the findings are explored.
Assuntos
Envelhecimento/psicologia , Atitude , Emprego/psicologia , Aposentadoria/psicologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Escolaridade , Nível de Saúde , Humanos , Renda , Relações Interpessoais , Estudos Longitudinais , Masculino , Análise Multivariada , Ocupações , Pensões , Fatores de TempoRESUMO
Nervous tissue-specific S-100 protein was quantified immunologically in maturing cerebrum, cerebellum and brain stem of guinea pigs during prenatal development. It was found to accumulate in its membrane-bound (pentanol-extractable) form concomitant with the accumulation of the water-soluble S-100 during development, indicating an ability of membranous structures to incorporate S-100 already during development.
Assuntos
Química Encefálica , Encéfalo/embriologia , Proteínas do Tecido Nervoso/análise , Proteínas S100/análise , Animais , Tronco Encefálico/análise , Tronco Encefálico/embriologia , Cerebelo/análise , Cerebelo/embriologia , CobaiasRESUMO
We have described a fatal case of autoimmune hemolysis associated with marked organ ischemia and lactic acidosis. Serologically the case was unusual because of the marked autoagglutination due to a warm antibody. Red cell agglutination at normal body temperature may have contributed to massive liver necrosis, lactic acidosis, and death.