PubMed Health⌕ Search

Biomedical subjects

Michael J González

Publications and source records attributed to Michael J González.

14 recordsLinked to original sources
PubMed2006

Tumor growth parameters of in-vivo human breast carcinoma: a proposed mathematical model for tumor growth kinetics.

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 "vivo" tumors.

Breast Neoplasms↗
PubMed2005

Orthomolecular oncology review: ascorbic acid and cancer 25 years later.

The effect of ascorbic acid on cancer has been a subject of great controversy. This is a follow-up review of the 1979 article by Cameron, Pauling, and Leibovitz published in Cancer Research. In this updated version, the authors address general aspects of ascorbic acid and cancer that have been presented before, while reviewing, analyzing, and updating new existing literature on the subject. In addition, they present and discuss their own mechanistic hypothesis on the effect of ascorbic acid on the cancer cell. The objective of this review is to provide an updated scientific basis for the use of ascorbic acid, especially intravenously as adjuvant treatment in pharmacological nutritional oncology.

Antioxidants↗
PubMed2005

Effect of a dietary supplement combination on weight management, adipose tissue, cholesterol and triglycerides in obese children.

A dietary supplement combination consisting of vitamins, minerals and fibers was studied to determine its safety and efficacy on weight/fat loss, cholesterol and triglycerides in children between ages 7-13. This open label trial measured total body weight, body fat percentage, waist circumference, total cholesterol, triglycerides before and after 6 weeks of treatment. The study population consisted of 25 mildly to moderate obese, otherwise healthy children of both sexes. After 6 weeks of treatment, the combination supplement had a statistically significant (p < 0.05) weight reducing effect. This weight reduction was associated with a corresponding statistically significant (p < 0.0001l) decrease in body fat percentage. In addition, significant decreases in total cholesterol (p < 0.0001) and triglycerides (p < 0.0001) were obtained, plus reductions in waist measurements. We conclude that the combination supplement studied herein is a safe and effective way to assist children in weight, fat percentage, cholesterol and triglyceride reduction.

Adipose Tissue↗
PubMed2005

A pilot clinical study of continuous intravenous ascorbate in terminal cancer patients.

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.

Ascorbic Acid↗
PubMed2004

Cell membrane fatty acid composition differs between normal and malignant cell lines.

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.

Animals↗
PubMed2004

Intravenous vitamin C as a chemotherapy agent: a report on clinical cases.

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.

Aged↗
PubMed2004

A vitamin, mineral, herb dietary supplement effect on blood glucose in uncontrolled type II diabetic subjects.

We tested a dietary supplement formulated with a synergistic combination of vitamins, minerals, herbals in a group of 15 patients with uncontrolled diabetes type II. The supplement was given for 30 days. Fasting blood glucose was measured prior to the supplementation and at the end of the 30 days treatment period. Blood glucose was significantly reduced in all patients with no adverse effects. This orthomolecular correction of faulty glucose metabolism with a combination of nontoxic, safe and fairly inexpensive nutraceuticals needs to be further substantiated. Nervertheless the idea of correcting metabolism with micronutrients is a new concept of genetic nutritioneering that seems appealing and cost effective.

Adult↗
PubMed2004

Effect of a dietary supplement combination on weight management, adipose tissue, cholesterol and triglycerides in obese subjects.

A combination dietary supplement containing vitamins, minerals, herbs, fibers and amino acids was studied to determine its safety and efficacy on weight/ fat loss, cholesterol and triglycerides in a double-blind, placebo-controlled trail. Total body weight, body fat %, waist and hip measurements, total cholesterol and triglycerides were evaluated before and after 6 weeks treatment with combination supplement or placebo. The study population consisted in 27 mildly to moderately obese, otherwise healthy, volunteers. After 6 weeks of treatment, the combination supplement had a statistically significant (p<0.001, mu=0.05) positive weight reducing effect (-8.59Lb vs. +2.14 Lb). This weight reduction was associated with a corresponding statistically significant (p<0.001, mu=0.05) decrease in body fat % in the treatment group (-2.88%) vs. the placebo (+0.86%). In addition, significant decreases in total cholesterol (-22.94 mg/dL) and triglycerides (-39.29 mg/dL) were obtained plus reductions in waist and hip measurements. These positive results lead us to conclude, that the combination supplement studied herein is a safe and effective way to assist in weight/fat reduction and decreases in total cholesterol and triglycerides in relatively short time (6 weeks).

Adipose Tissue↗
PubMed2003

Intravenous ascorbic acid: protocol for its application and use.

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.

Anti-Infective Agents↗
PubMed2002

Inhibition of human breast carcinoma cell proliferation by ascorbate and copper.

We tested the effect of different concentrations of ascorbic acid (AA), 50, 100, 250 mg/500 mg/dL) with copper sulfate (CS), 10 mg/dL) on human breast carcinoma (MDA-MB231) cell proliferation in vitro. Cell proliferation was measured using a colori-metric assay (Cell proliferation kit II (XTT), Boehringer, NJ). The results of the mean absorbance of the tissue culture at different AA concentrations and a constant CS concentration were as follow: 0.82 +/- 0.03 (control, mean +/- SE), 0.64 +/- 0.02 (CS above); 0.48 +/- 0.03 (50 mg/dL) AA), 0.21 +/- 0.02 (100 mg/dL), 0.08 +/- 0.01 (250 mg/dL) AA, 0.60 +/- 0.05 (500 mg/dL). These results show that a combination of AA and CS inhibits human breast carcinoma cell proliferation in vitro. This cell proliferation inhibitory effect is directly proportional to the AA concentration with the exception of the 500 mg/dL AA dose. This chemotherapeutic effect was optimally enhanced when AA was added at a concentration of 250 mg/dL. The AA concentrations of 500 mg/dL had a biphasic effect on tumor cell proliferation probably due to back and forth redox reactions between AA and dehydroascorbic acid in a closed system. This study provides preliminary evidence that AA and SC can be used as biological response modifiers (BRM) for tumor growth inhibition.

Ascorbic Acid↗
PubMed2002

Orthomolecular oncology: a mechanistic view of intravenous ascorbate's chemotherapeutic activity.

The effect of vitamin C in cancer has been a subject of great controversy; mainly because of the inconsistent results obtained by oral intakes of ascorbate when used as an anticancer agent. We believe the intravenous application of ascorbate will provide more consistent results in cancer patients since Vitamin C blood levels attained are substantially higher in a range proven cytotoxic to malignant cells. In this article we will present and discuss our proposed mechanism on the chemotherapeutic activity exhibited by ascorbate.

Antioxidants↗
PubMed2002

Effects of a high molecular mass Convolvulus arvensis extract on tumor growth and angiogenesis.

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.

Animals↗
PubMedDate not supplied

[Adverse effects and interactions of medicinal herbal products].

The use of medicinal products derived from plants (phytomedicinals) has been increasing dramatically in the past years this has forced the health professional to increase their knowledge in the risks and benefits in the use of such products. This article reviews the most important adverse effects and interactions from the phytomedicinals and presents this information in the perspective of a responsible Integrative Medicine practice focused in achieving optimal therapeutic goals.

Drug Interactions↗