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To provide an overview of molecular and cellular processes involved in erectile dysfunction (ED) with emphasis on circulating endothelial progenitor cells (EPC) and discuss possible nutraceutical means of intervention. A review of literature on Pubmed related to EPC and ED was conducted. Patients with ED appear to possess a reduced number of circulating EPC, which is associated with poor endothelial function possibly as a result of underlying low-grade inflammation. Several studies support the possibility of improving erectile function by inhibition of inflammation as well as administration of various stem cell types. One particularly interesting approach is nutraceutical supplementation to increase circulating EPC, as demonstrated in the product Stem-Kine. Interventions aimed at increasing circulating EPC may have potential in treatment of vascular ED.
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Células Endoteliales/citología , Disfunción Eréctil/tratamiento farmacológico , Células Madre/citología , Proteína C-Reactiva/metabolismo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Movilización de Célula Madre Hematopoyética/métodos , Humanos , Inflamación , Masculino , Ciencias de la Nutrición , Pene/patología , Resultado del TratamientoRESUMEN
Our study aimed to establish the association of vitamin D status with the level of circulating endothelial progenitor cells (EPCs) and circulating angiogenic cells (CACs) and to demonstrate the effect of vitamin D on the level of lipoproteins responsible for increased cardiovascular risk and high blood pressure. 41 healthy adults were selected. EPCs were defined as CD34+/KDR+ cells, and CACs were defined as cells that expressed endothelial markers after incubation of mononuclear blood cells with endothelial growth factors during 5 days. We found a positive association between EPCs, CACs and the level of vitamin D and an inverse correlation between several subclasses of lipoproteins. The level of vitamin D higher than 40 ng/ml demonstrated a positive effect on regulation of blood pressure, and there was significant difference in cholesterol/HDL ratio, very low-density lipoproteins, and triglycerides for groups of subjects with varying levels of vitamin D.
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Enfermedades Cardiovasculares/tratamiento farmacológico , Células Endoteliales/citología , Células Madre/citología , Vitamina D/sangre , Adulto , Anciano , Antígenos CD34/biosíntesis , Presión Sanguínea , HDL-Colesterol/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , Persona de Mediana Edad , Factores de Riesgo , Factores de Tiempo , Triglicéridos/metabolismoRESUMEN
There is a strong advocacy movement for large doses of vitamin C. Some authors argue that the biological half-life for vitamin C at high plasma levels is about 30 minutes, but these reports are the subject of some controversy. NIH researchers established the current RDA based upon tests conducted 12 hours (24 half lives) after consumption. The dynamic flow model refutes the current low-dose recommendations for dietary intakes and links Pauling's mega-dose suggestions with other reported effects of massive doses of ascorbate for the treatment of disease. Although, a couple of controlled clinical studies conducted at The Mayo Clinic did not support a significant benefit for terminal cancer patients after 10 grams of once-a-day oral vitamin C, other clinical trials have demonstrated that ascorbate may indeed be effective against tumors when administered intravenously. Recent studies confirmed that plasma vitamin C concentrations vary substantially with the route of administration. Only by intravenous administration, the necessary ascorbate levels to kill cancer cells are reached in both plasma and urine. Because the efficacy of vitamin C treatment cannot be judged from clinical trials that use only oral dosing, the role of vitamin C in cancer treatment should be reevaluated. One limitation of current studies is that pharmacokinetic data at high intravenous doses of vitamin C are sparse, particularly in cancer patients. This fact needs prompt attention to understand the significance of intravenous vitamin C administration. This review describes the current state-of-the-art in oral and intravenous vitamin C pharmacokinetics. In addition, the governmental recommendations of dose and frequency of vitamin C intake will also be addressed.
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Humanos , Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/farmacocinética , Administración Oral , Ácido Ascórbico/metabolismo , Disponibilidad Biológica , Inyecciones IntravenosasRESUMEN
Many mathematical models have been proposed to study tumor growth parameters in vivo. Nevertheless most of the medical models have given variable results even when experimental conditions are exactly the same. There are multiple factors that are capable of affecting tumor growth that should be taken into account when proposing a mathematical model for tumor growth in vivo. We discuss here own proposed model for tumor growth kinetics utilizing a modified Gompertz function that better responds to the growth characteristic of in [quot ]vivo[quot ] tumors.
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Humanos , Modelos Teóricos , Neoplasias de la Mama/patología , Cinética , Proliferación CelularRESUMEN
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.
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Humanos , Masculino , Femenino , Ácido Ascórbico/administración & dosificación , Neoplasias/tratamiento farmacológico , Vitaminas/administración & dosificación , Infusiones Intravenosas , Proyectos Piloto , Cuidado TerminalRESUMEN
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
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Humanos , Masculino , Femenino , Persona de Mediana Edad , Ácido Ascórbico/administración & dosificación , Antineoplásicos/administración & dosificación , Antioxidantes/administración & dosificación , Neoplasias/tratamiento farmacológico , Ácido Ascórbico/efectos adversos , Antineoplásicos/efectos adversos , Antioxidantes/efectos adversos , Inyecciones Intravenosas , Resultado del TratamientoRESUMEN
Twenty-eight fatty acids (C8:0 to C24:l n-9) were measured by gas chromatography in four normal cell lines (C3H / 10T1 / 2, CCD-18Co, CCD-25SK and CCD-37Lu) and seven cancer cell lines (C-41, Caov-3, LS-180, PC-3, SK-MEL-28, SK-MES-1 and U-87 MG). Results show differences in the content and proportions of fatty acids when comparing cancer cell lines with their normal counterparts. Cancer cell lines showed lower C20: 4 n-6, C24:1 n-9, polyunsaturated fatty acids (PUFA's) and ratios of C20:4 n-6 to C20:5 n-3 and C16:0 to C18:1 n-9 and stearic to oleic (SA/OA) than their normal counterparts. All cancer cell lines had SA/OA ratios lower than 7.0 while normal cell lines had ratios greater than 0.7 (p<0.05). In addition, the ratios of total saturated fatty acids (SFA) to PUFA'S and the concentration of C18:1 n-9, C18:2 n-6, C20:5 n-3 were higher in cancer cell lines as compared to normal cell lines. A positive correlation was detected between C16:0 and longer SFA'S (r = +0.511, p<0.05) in normal cell lines whereas a negative correlation (r=0.608, p<0.05) was obtained for malignant cell lines. Moreover, cancerous cell lines exhibited a particular desaturation defect and an abnormal incorporation of C18:2 n-6 and C20-4 n-6 fatty acids
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Humanos , Ratones , Ácidos Grasos/análisis , Línea Celular Tumoral/química , Membrana Celular/química , Ácidos Grasos/metabolismo , Línea Celular Tumoral/metabolismo , Membrana Celular/metabolismoRESUMEN
The aim of this study was to evaluate the development of edema, and superficial and deep vein thrombosis (DVT) prophylaxis with an oral profibrinolytic agent (Flite Tabs, 150 mg pinokinase, Aidan, Tempe, AZ, USA) in long-haul flights (7-8 hours), in high-risk subjects. A group of 300 subjects was included; 76 were excluded for several problems including concomitant treatments; 204 were randomized into 2 groups (active treatment or placebo) to evaluate the effects of prophylaxis with Flite Tabs. An exercise program was used in both groups. The femoral, popliteal, tibial, and superficial veins were scanned with ultrasound before and within 90 minutes after flights. Of the included subjects, 92 of 103 controls and 94 of 101 treated subjects completed the study. Dropouts were due to connection problems. Age, gender, and risk distribution were comparable in the groups. In the treatment group, no DVT was observed. In the control group, 5 subjects (5.4%) had a DVT and there were 2 superficial thromboses (7 events in 92 subjects; 7.6%). At inclusion, edema was comparable in the 2 groups. After flights there was an increase in score in controls (+12%) in comparison with a decrease (-15%) in the Flite Tabs group (the difference in variation was statistically significant). Intention-to-treat analysis for thrombotic events shows 18 failures in controls (11 lost to follow-up + 7 thrombotic events) of 92 subjects (19.6%) in comparison with 7 failures (of 94 subjects, equivalent to 7.4%) in the treatment group (p < 0.05). Events were asymptomatic. In conclusion, Flite Tabs were effective in reducing thrombotic events and in controlling edema in high-risk subjects in long flights.
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Flavonoides/administración & dosificación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Subtilisinas/administración & dosificación , Viaje , Trombosis de la Vena/prevención & control , Adulto , Medicina Aeroespacial , Anciano , Cápsulas , Combinación de Medicamentos , Edema/etiología , Edema/prevención & control , Ejercicio Físico , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Fibrinógeno/análisis , Flavonoides/efectos adversos , Humanos , Pierna/irrigación sanguínea , Masculino , Persona de Mediana Edad , Extractos Vegetales , Inhibidores de Agregación Plaquetaria/efectos adversos , Factores de Riesgo , Subtilisinas/efectos adversos , Ultrasonografía , Venas/diagnóstico por imagen , Trombosis de la Vena/etiología , Trombosis de la Vena/fisiopatologíaRESUMEN
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.
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Humanos , Ácido Ascórbico/administración & dosificación , Antiinfecciosos , Ácido Ascórbico/efectos adversos , Ácido Ascórbico/farmacología , Ácido Ascórbico/uso terapéutico , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Protocolos Clínicos , Relación Dosis-Respuesta a Droga , Infecciones Bacterianas/tratamiento farmacológico , Infusiones Intravenosas , Neoplasias/tratamiento farmacológico , VirosisRESUMEN
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.
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Humanos , Convolvulus , Neoplasias/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Fitoterapia , Preparaciones de Plantas/uso terapéutico , Células Cultivadas , Linfocitos/efectos de los fármacos , Ratones , Peso Molecular , Neoplasias/patologíaRESUMEN
Vitamin C (ascorbate) is toxic to tumour cells, and has been suggested as an adjuvant cancer treatment. Our goal was to determine if ascorbate, in combination with other antioxidants, could kill cells in the SW620 hollow fibre in vitro solid tumour model at clinically achievable concentrations. Ascorbate anti-cancer efficacy, alone or in combination with lipoic acid, vitamin K3, phenyl ascorbate, or doxorubicin, was assessed using annexin V staining and standard survival assays. 2-day treatments with 10 mM ascorbate increased the percentage of apoptotic cells in SW620 hollow fibre tumours. Lipoic acid synergistically enhanced ascorbate cytotoxicity, reducing the 2-day LC(50)in hollow fibre tumours from 34 mM to 4 mM. Lipoic acid, unlike ascorbate, was equally effective against proliferating and non-proliferating cells. Ascorbate levels in human blood plasma were measured during and after intravenous ascorbate infusions. Infusions of 60 g produced peak plasma concentrations exceeding 20 mM with an area under the curve (24 h) of 76 mM h. Thus, tumoricidal concentrations may be achievable in vivo. Ascorbate efficacy was enhanced in an additive fashion by phenyl ascorbate or vitamin K3. The effect of ascorbate on doxorubicin efficacy was concentration dependent; low doses were protective while high doses increased cell killing.
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Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Ácido Ascórbico/farmacología , Carcinoma/patología , Neoplasias del Colon/patología , Ácido Tióctico/farmacología , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacología , Interacciones Farmacológicas , Humanos , Necrosis , Células Tumorales CultivadasRESUMEN
Background. Elevated serum total cholesterol (TC) and triglycerides (TG) are risk factors for atherosclerosis and ischemic heart disease. Adult growth hormone deficiency (AGHD) is associated with elevated TC and TG. Many treatment protocols for AGHD use relatively high doses of growth hormone (GH) given at low frequency, which is associated with increased incidences of edema, joint pains, and carpal tunnel syndrome. We have treated > 2200 patients using a low-dose high frequency (LDHF) dosing regimen of GH which results in similar beneficial subjective responses, and fewer of the side-effects associated with the higher-dosage treatment at a substantial cost savings. Clinically, in addition to increased insulin-like growth factor I (IGF-I), we observed lower TG and TC levels and no elevation of prostate specific antigen levels in treated patients. Methods. A retrospective analysis of IGF-I, TG, TC, and PSA data from our patient population was performed to test our hypothesis that positive objective responses of IGF-I, TG, and TC occur and that elevation of PSA does not occur in response to LDHF dosing regimen of GH. The mean duration of treatment of the analyzed data ranged from 181 to 259 days. Results. The mean plasma IGF-I level rose significantly (p<.00001) to a level 37% greater than baseline with treatment. TC and TG decreased significantly (p<.001) in those patients with elevated baseline values, and did not change significantly in those with normal baseline values. PSA concentrations decreased non-significantly during treatment, and few cases of edema, joint pain, or carpal tunnel were reported. Conclusions. Treatment of AGHD using the LDHF dosing regimen of GH resulted in significant increases in IGF-I, significant reductions in TC and TG levels in patients with elevated baseline values, no increase in PSA concentrations, and fewer side effects than other dosing regimens.
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The use of alternative/complementary medicine has been increasing considerably. Conventional medicine must begin to address issues related to the use, safety, regulation, research and education of alternative/complementary medicine. Integrative medicine combines conventional medicine and alternative complementary practices. Integrative medicine is an innovative approach to medicine and medical education. It involves the understanding of the interaction of the mind, body and spirit and how to interpret this relationship in the dynamics of health and disease. Integrative medicine shifts the orientation of the medical practice from disease based approach to a healing based approach. It does not reject conventional medicine nor uncritically accepts unconventional practices. Integrative medicine is an effective, more fulfilling human approach to medicine based on the benefit of the patient by following good medicine practices in a scientific manner.
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Terapias Complementarias/educación , Prestación Integrada de Atención de Salud/tendencias , Educación Médica/tendencias , Salud Holística , Humanos , Puerto RicoRESUMEN
Lipid peroxidation has been shown to both enhance carcinogenesis and to have an anticarcinogenic effect. This paradox is of great relevance to the fields of free radical biology, biochemistry, pathology, nutrition and oncology among others and needs to be addressed. A proper understanding of this issue can be a key to more effective treatment of malignant tumors in the near future.
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Transformación Celular Neoplásica , Peroxidación de Lípido , Modelos Biológicos , Neoplasias/fisiopatología , Anticarcinógenos , Antioxidantes , Muerte Celular , Radicales Libres/metabolismo , Humanos , Neoplasias/genética , Neoplasias/patología , Neoplasias/prevención & controlRESUMEN
Ascorbic acid and its salts (AA) are preferentially toxic to tumor cells in vitro and in vivo. Given in high enough doses to maintain plasma concentrations above levels that have been shown to be toxic to tumor cells in vitro, AA has the potential to selectively kill tumor cells in a manner similar to other tumor cytotoxic chemotherapeutic agents. Most studies of AA and cancer to date have not utilized high enough doses of AA to maintain tumor cytotoxic plasma concentrations of AA. Data are presented which demonstrate the ability to sustain plasma levels of AA in humans above levels which are toxic to tumor cells in vitro and suggests the feasibility of using AA as a cytotoxic chemotherapeutic agent.
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Antineoplásicos/uso terapéutico , Ácido Ascórbico/uso terapéutico , Neoplasias/tratamiento farmacológico , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/toxicidad , Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/toxicidad , Carcinoma de Ehrlich , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Infusiones Intravenosas , Neoplasias Pulmonares/tratamiento farmacológico , Ratones , Células Tumorales CultivadasRESUMEN
An improved method has been developed to count cells in situ based on the measurement of esterase activity with carboxyfluorescein diacetate. This sensitive, semiautomated microplate fluorometer assay was able to estimate viable cell numbers over a range of 5 x 10(2) to 2.6 x 10(5) cells/well in a tumor cell line. Sensitivity to 10(3) was demonstrated in two other cell lines. Sub- and supranormal fluorescence events which can be responsible for unreliable readings when using a fluorescence assay for cell counting were quantified in a menadione (cytotoxic agent)/U-87 MG (cell line) model. There was a close correlation between the fluorometer method and Coulter counter method for two different tumor cell lines when this method was performed on cells after sub- and supranormal fluorescence events had ceased.