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1.
P. R. health sci. j ; 24(4): 269-276, Dec. 2005.
Artigo em Inglês | LILACS | ID: lil-472815

RESUMO

Case studies suggest that vitamin C, given intravenously at doses of 10-100 grams/day can improve patient well being and in some cases, reduce tumor size. While ascorbate is generally considered safe, clinical data on high intravenous doses is limited. Twenty-four late stage terminal cancer patients were given continuous infusions of 150 to 710 mg/kg/day for up to eight weeks. Blood chemistry and blood count profiles were obtained at roughly one-week intervals while patient health, adverse events and tumor progression were monitored. The majority of patients were vitamin C deficient prior to treatment. Intravenous infusions increased plasma ascorbate concentrations to a mean of 1.1 mM. The most common adverse events reported were nausea, edema, and dry mouth or skin; and these were generally minor. Two Grade 3 adverse events 'possibly related' to the agent were reported: one patient with a history of renal calculi developed a kidney stone after thirteen days of treatment and another patient experienced hypokalemia after six weeks of treatment. White blood cell counts were stable while hemoglobin and hematocrit levels dropped slightly during treatment, consistent with trends observed prior to therapy. Blood creatinine, BUN, glucose, and uric acid concentrations decreased or remained stable during therapy, suggesting that ascorbate infusions did not adversely affect renal function. One patient had stable disease and continued the treatment for forty-eight weeks. These data suggest that intravenous vitamin C therapy for cancer is relatively safe, provided the patient does not have a history of kidney stone formation.


Assuntos
Humanos , Masculino , Feminino , Ácido Ascórbico/administração & dosagem , Neoplasias/tratamento farmacológico , Vitaminas/administração & dosagem , Infusões Intravenosas , Projetos Piloto , Assistência Terminal
2.
P. R. health sci. j ; 24(2): 145-150, Jun. 2005.
Artigo em Inglês | LILACS | ID: lil-472967

RESUMO

Sodium ascorbate is preferentially toxic to tumor cells at high concentrations. It has not been established, however, whether sufficient intra-tumor ascorbate concentrations are safely achievable in vivo. We administered sodium ascorbate subcutaneously or orally for eighteen days to Sewall-Wright strain-2 guinea pigs bearing intradermal L-10 hepatocarcinoma tumors. Tumor masses and intra-tumor ascorbate concentrations were determined at necropsy. L-10 cells formed tumors that metastasized to the lymph nodes, with tumor burdens reaching nearly 50 grams in untreated animals. Subcutaneous injections of ascorbate (500 mg/kg/day) inhibited tumor growth by as much as sixty-five percent, with oral supplementation reducing it by roughly fifty percent. Tumor growth correlated inversely with intra-tumor ascorbate concentration, the latter exceeding 2 mM in some cases. Ascorbate concentrations sufficient to kill tumor cells can be safely achieved in solid tumors in vivo, suggesting a possible role for high dose intravenous ascorbate in treating cancer.


Assuntos
Animais , Ácido Ascórbico/administração & dosagem , Antioxidantes/administração & dosagem , Linhagem Celular Tumoral/efeitos dos fármacos , Ácido Ascórbico/análise , Antioxidantes/análise , Relação Dose-Resposta a Droga , Cobaias , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Processos de Crescimento Celular/efeitos dos fármacos
3.
P. R. health sci. j ; 23(2): 115-118, Jun. 2004.
Artigo em Inglês | LILACS | ID: lil-390793

RESUMO

A series of seven cases are presented in which intravenous vitamin C has been used as antineoplastic agent in the treatment of different types of cancers. The cancers cases reviewed are the following: Renal cell carcinoma (2), Colorectal cancer (1), Pancreatic cancer (1), Non-Hodgkin's lymphoma (2) and breast cancer (1). Toxic reactions were not observed at these high doses of intravenous Vitamin C. All patients were prescreened for Glucose 6--phosphate dehydrogenase deficiency before administering intravenous Vitamin C in order to prevent hemolysis


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Ácido Ascórbico/administração & dosagem , Antineoplásicos/administração & dosagem , Antioxidantes/administração & dosagem , Neoplasias/tratamento farmacológico , Ácido Ascórbico/efeitos adversos , Antineoplásicos/efeitos adversos , Antioxidantes/efeitos adversos , Injeções Intravenosas , Resultado do Tratamento
4.
P. R. health sci. j ; 22(3): 287-290, Sept. 2003.
Artigo em Inglês | LILACS | ID: lil-355994

RESUMO

High dose intravenous(i.v.) ascorbic acid (AA) has been used as therapy for infectious disease from bacterial and viral origin and adjuvant therapy for cancer. In this publication we describe a clinical protocol that has been developed over the past twenty years utilizing high dose i.v. AA as therapy for cancer. This includes principles of treatment, rationale, baseline workup, infusion protocol, precautions and side effects.


Assuntos
Humanos , Ácido Ascórbico/administração & dosagem , Anti-Infecciosos , Ácido Ascórbico/efeitos adversos , Ácido Ascórbico/farmacologia , Ácido Ascórbico/uso terapêutico , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Protocolos Clínicos , Relação Dose-Resposta a Droga , Infecções Bacterianas/tratamento farmacológico , Infusões Intravenosas , Neoplasias/tratamento farmacológico , Viroses
5.
P. R. health sci. j ; 21(4): 323-338, Dec. 2002.
Artigo em Inglês | LILACS | ID: lil-356232

RESUMO

BACKGROUND: Plant materials represent promising sources of anti-cancer agents. We developed and tested a novel extract from the ubiquitous plant Convolvulus arvensis. MATERIALS AND METHODS: Convolvulus arvensis components were extracted in boiling water, and small molecules were removed by high-pressure filtration. The extract's biological activity was assessed by measuring its effects on S-180 fibrosarcoma growth in Kun Ming mice and on heparin-induced angiogenesis in chick embryos. We also examined the extract's effects on lymphocytes ex vivo and tumor cell growth in vitro. RESULTS: The extract (primarily proteins and polysaccharides) inhibited tumor growth in a dose-dependent fashion when administered orally. At the highest dose tested, 200 mg/kg/day, tumor growth was inhibited by roughly seventy percent. Subcutaneous or intraperitoneal administration at 50 mg/kg/day also inhibited tumor growth by over seventy percent. The extract's acute LD50 in Kun Ming mice was 500 mg/kg/day when injected, indicating that tumor growth inhibition occurred at non-toxic doses. It inhibited angiogenesis in chick embryos, improved lymphocyte survival ex vivo, and enhanced yeast phagocytosis, but did not kill tumor cells in culture. CONCLUSION: High molecular mass extract deserves further study as an anti-cancer agent.


Assuntos
Humanos , Convolvulus , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Fitoterapia , Preparações de Plantas/uso terapêutico , Células Cultivadas , Linfócitos/efeitos dos fármacos , Camundongos , Peso Molecular , Neoplasias/patologia
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