Analysis of botanicals and dietary supplements for antioxidant capacity: a review

Free radicals and other reactive species are considered to be important causative factors in the development of diseases of aging such as cancer and cardiovascular diseases. This relationship has led to considerable interest in assessing the antioxidant capacity of foods and botanicals and other nutritional antioxidant supplements. The use of the oxygen radical absorbance capacity (ORAC) assay as a tool for antioxidant assessment is described and proposed as a method for comparing botanical sources and for standardizing nutritional supplements. The free radical or oxidant source is important and direct comparisons cannot be made between procedures that use different sources. The ORAC procedure uses 2,2'-azobis(2-amidinopropane) dihydrochloride as a peroxyl radical source, which is relevant to biological systems because the peroxyl radical is the most abundant free radical. Other oxidant sources (hydroxyl radical and Cu++) can also be used to characterize antioxidants in botanicals. Phenolics or polyphenolics are responsible for most of the antioxidant capacity in fruits, vegetables, and most botanical antioxidant supplements. Although little is known about the absorption and metabolism of these components, improvement in the in vivo antioxidant status has been observed in human subjects following consumption of antioxidant botanicals. The ORAC method provides a basis from which to establish appropriate dietary intakes that might impact health outcomes.

Stress proteins are not induced in mammalian cells exposed to radiofrequency or microwave radiation

The induction of stress proteins in HeLa and CHO cells was investigated following a 2 h exposure to radiofrequency (RF) or microwave radiation. Cells were exposed or sham exposed in vitro under isothermal (37 +/- 0.2 degrees C) conditions. HeLa cells were exposed to 27- or 2450 MHz continuous wave (CW) radiation at a specific absorption rate (SAR) of 25 W/kg. CHO cells were exposed to CW 27 MHz radiation at a SAR of 100 W/kg. Parallel positive control studies included 2 h exposure of HeLa or CHO cells to 40 degrees C or to 45 microM cadmium sulfate. Stress protein induction was assayed 24 h after treatment by electrophoresis of whole-cell extracted protein labeled with [35S]-methionine. Both cell types exhibited well-characterized responses to the positive control stresses. Under these exposure conditions, neither microwave nor RF radiation had a detectable effect on stress protein induction as determined by either comparison of RF-exposed cells with sham-exposed cells or comparison with heat-stressed or Cd++ positive control cells.

[Optimal treatment parameters for damage of chicken comb vessels using chlorophyll derivative IV in photodynamic therapy]

OBJECTIVE

To define the optimal treatment parameters of chlorophyll derivative IV (CPD4) in photodynamic therapy(PDT) of port wine stains(PWS) by observing the morphological changes of chicken combs.

METHODS

102 animals were divided into 6 groups at random, including 3 control groups(given no treatment, given light without photosensitizer or given photosensitizer without light) and 3 experimental groups treated with different CPD4 dosages(5, 7.5, 10, 12.5, 15 mg/kg body weight), power density(50, 100, 150, 200 mW/cm2), energy density (15, 30, 45, 60, 120, 135, 180 J/cm2) and different intervals between CPD4 injection and irradiation (immediately, 5, 10, 20, 30, 60, 120, 180, 240 minutes). The main emitting peak of light source was at 650 nm, and CPD4 was injected intravenously, then the appearance of chicken comb was recorded everyday. The prepared sections were stained with HE. The histological changes of chicken comb were observed by light microscope.

RESULTS

The control animals showed no significant comb changes, while the PDT could cause blanching of the chicken comb in the experimental group. The histologic changes included damage of erythrocytes and endothelial cells, vascular rupture, hemorrhage or disappearance, denaturation of perivascular collagen fiber and local necrosis of chicken combs. The treatment parameters which caused the most obvious blanching of the chicken comb were 7.5-10 mg/kg body weight of CPD4 dosage, 100-150 mW/cm2 of power density, 60-90 J/cm2 of energy density, and the intervals between CPD4 injection and irradiation were 0-20 minutes.

CONCLUSION

CPD4 in PDT can cause selective damage of dermal capillaries in chicken comb and blanching of the chicken comb with optimal treatment parameters. The results will offer the basis for further investigation of clinic treatment parameters.

[Biodistribution and metabolism of radio-iodinated IBZM in rats]

The aim of this study was to assess the bio-distribution and metabolic behavior of radio-iodinated IBZM in rats. Routine and improved technologies were used. The results showed that the radio-iodinated IBZM had favorable bio-distribution and metabolic behavior. The radio-distribution was high and the radio-iodinated IBZM remained long in striatum where no metabolic by-products manifested at 30 minutes after injection. These suggested that radio-iodinated IBZM is an excellent dopamine D2 receptor imaging agent for SPECT in humans, and it is stressed that thyroid must be blocked by iodine during the study of imaging.

Alcohol intake and mortality: findings from the National Health Interview Surveys (1988 and 1990)

The authors used prospective data from two supplemental studies of the National Health Interview Survey, the 1988 Alcohol Supplement and the 1990 Health Promotion and Disease Prevention Supplement, to examine the relation between alcohol intake and mortality. Their study included 17,821 men and 25,874 women aged 40 years or older at baseline; during an average of 6 years of follow-up, 5,540 deaths occurred. The alcohol-mortality relation was U-shaped for men and J-shaped for women. On the basis of categorical analyses adjusted for age, race, smoking, and baseline diseases, men who drank 2 drinks per day had a significantly lower risk of death compared with abstainers (relative risk = 0.60, 95% confidence interval (CI): 0.45, 0.82). The relative risk was 0.75 (95% CI: 0.55, 1.03) after further adjustment for marital status, education, and self-perceived health status. For women, the corresponding relative risks were 0.69 (95% CI: 0.61, 0.78) and 0.79 (95% CI: 0.70, 0.90) for those who drank less than 1 drink per day. When drinking category was considered as an ordinal variable and fitted with a quadratic function in the Cox model, the estimated optimal alcohol intake was approximately less than 1 to 1 drink per day for men and lifetime infrequent to less than 1 drink per day for women. Data from these representative US cohorts demonstrated that less than 2 drinks per day for men and less than 1 drink per day for women are associated with the lowest all-cause mortality.

["Three steps procedure" in the treatment of large pancreatic head cancer]

OBJECTIVE

To evaluate the feasibility and effectivity of "3 steps procedure" in the treatment of large pancreatic head cancer.

METHODS

The "3 steps procedure" consisted of decompression of jaundice by simple cholecystotomy, intervenient (intra-arterial) chemotherapy (5-FU 1 approximately 1.5 g, mitomycin 8 approximately 14 mg, cisplatin 40 approximately 60 mg and octreatide 1 mu intravenously as near the superior and inferior pancreatic-duodenal arteries as possible), and then the reasonable regional pancreatic-duodenectomy.

RESULTS

All 16 tumors were radically resected. Conventional and regional pancreatic-duodenectomy was done in 7 and 9 patients, respectively; of the later group, artificial prosthesis for portal vein bridge was done in 3 patients, end-to-end anastomosis in 4 and repair after partial resection of invaded vessel wall in 2.

CONCLUSION

The "3 steps procedure" is feasible and effective in the treatment of large pancreatic head cancer.

Effect of fruits, vegetables, or vitamin E--rich diet on vitamins E and C distribution in peripheral and brain tissues: implications for brain function

Age-related neurodegenerative conditions are the principal cause of declining cognitive and motor function during aging. Evidence support that fruits and vegetables containing generous amounts of antioxidant nutrients are important for neurological function. We investigated the effect of diets enriched with fruits or vegetables but low in vitamin E and a diet high in vitamin E on the distribution of vitamins C and E in the brain and dopamine release of Fischer 344 rat model, over an 8-month period. The low-vitamin E diet resulted in lowered alpha-tocopherol levels in brain and peripheral tissues, whereas the animals that received a diet enriched in vitamin E showed a significant increase, between 500-900%. Vitamin C concentration in plasma, heart, and liver was reduced in the vitamin E-supplemented group. It is concluded that supplementation or depletion of alpha-tocopherol for 8 months results in marked changes in vitamin E levels in brain tissue and peripheral tissues, and varied distribution of alpha-tocopherol throughout the different brain regions examined. In addition, compared to control group, rats supplemented with strawberry, spinach, or vitamin E showed a significant enhancement in striatal dopamine release. These findings suggest that other nutrients present in fruits and vegetables, in addition to the well-known antioxidants, may be important for brain function.

[The influence of physiologic factors on the expression of striatal dopamine D2 receptors]

The aim of this study was to know whether the strain, sex, and age-related body weight of rat have influence on the expression of striatal dopamine D2 receptor. The data on striatal dopamine D2 receptor binding 125I-IBZM in 34 rats were used in the comparison between pairs of groups matched on strain, sex, and body weight. The result showed that the strain and sex of rats had no influence on the striatal dopamine D2 receptor binding 125I-IBZM, but there was a body weight-related decrease in the striatal dopamine D2 receptor binding 125I-IBZM. The results suggest that age-dependent decline of striatal dopamine D2 receptors is possible; therefore, strict age-matching is necessary to clinical studies.

Quality of the last year of life of older adults: 1986 vs 1993

CONTEXT

The population is aging and life expectancy is increasing, but whether morbidity and disability late in life also increase is unknown.

OBJECTIVE

To examine whether the use of health care services, disability and cognitive function, and overall quality of life in the year before death among older adults has changed over time.

DESIGN AND SETTING

The 1986 and 1993 National Mortality Followback Surveys, which were probability samples of all deaths in the United States with response rates of next of kin of 90% and 88% for those aged 65 years and older.

PARTICIPANTS

Next of kin were asked to report the health status of a total of 9179 decedents who were 65 years and older in 1986 and 6735 in 1993, representing 1.5 and 1.6 million decedents aged 65 years and older.

MAIN OUTCOME MEASURES

Days of hospital or nursing home stays, number and length of disability in 5 activities of daily living, duration of impairment in 3 measures of cognitive function, and an overall sickness score among individuals aged 65 through 84 years and those aged 85 years and older.

RESULTS

Women used significantly fewer hospital and nursing home services in the last year of life in 1993 vs 1986 (mean reduction, 3.3 nights for both age groups for hospital services; mean reduction 18.4 nights for nursing home for women aged 65-84 years and 42.3 nights for women > or =85 years). Men had no changes except those aged 85 years and older had a decline in nursing home nights of 32.6. The proportion of women aged 85 years and older with restriction of at least 2 activities of daily living decreased from 62.5% in 1986 to 52.1% in 1993 (P<.01), and those with normal cognitive function increased from 50.3% to 56.2% (P<.05). Their mean overall sickness score decreased and quality-of-life improved. Among women aged 65 through 84 years, the number with normal cognitive function increased and the mean sickness score decreased, but those with at least 2 activities of daily living impairments increased and the overall quality of life declined. A similar pattern of change was found in the oldest-old men except that cognitive function worsened. Most parameters for men aged 65 through 84 years did not change significantly.

CONCLUSIONS

Men and women at least 85 years old in the US experienced a better overall quality of life in the last year of life in 1993 than those in 1986. Most measures for men and women aged 65 through 84 years improved or did not change.

Antioxidant capacity of oat (Avena sativa L.) extracts. 1. Inhibition of low-density lipoprotein oxidation and oxygen radical absorbance capacity

Milled oat groat pearlings, trichomes, flour, and bran were extracted with methanol and the fractions tested in vitro for antioxidant capacity against low-density lipoprotein (LDL) oxidation and R-phycoerythrin protein oxidation in the oxygen radical absorbance capacity (ORAC) assay. The oxidative reactions were generated by 2,2'-azobis(2-amidinopropane) HCl (AAPH) or Cu(2+) in the LDL assay and by AAPH or Cu(2+) + H(2)O(2) in the ORAC assay and calibrated against a Trolox standard to calculate Trolox equivalents (1 Trolox equivalent = 1 TE = activity of 1 micromol of Trolox). The antioxidant capacity of the oat fractions was generally consistent with a potency rank of pearlings (2.89-8.58 TE/g) > flour (1.00-3.54 TE/g) > trichome (1.74 TE/g) = bran (1.02-1.62 TE/g) in both LDL and ORAC assays regardless of the free radical generator employed. A portion of the oat antioxidant constituents may be heat labile as the greatest activity was found among non-steam-treated pearlings. The contribution of oat tocols from the fractions accounted for <5% of the measured antioxidant capacity. AAPH-initiated oxidation of LDL was inhibited by the oat fractions in a dose-dependent manner, although complete suppression was not achieved with the highest doses tested. In contrast, Cu(2+)-initiated oxidation of LDL stimulated peroxide formation with low oat concentrations but completely inhibited oxidation with higher doses. Thus, oats possess antioxidant capacity most of which is likely derived from polar phenolic compounds in the aleurone.

In vivo total antioxidant capacity: comparison of different analytical methods

Several methods have been developed to measure the total antioxidant capacity of a biological sample. The use of peroxyl or hydroxyl radicals as pro-oxidants in the oxygen radical absorbance capacity (ORAC) assay makes it different and unique from the assays that involve oxidants that are not necessarily pro-oxidants. An improvement in quantitation is achieved in the ORAC assay by taking the reaction between substrate and free radicals to completion and using an area-under-curve technique for quantitation compared to the assays that measure a lag phase. The interpretation of the changes in plasma or serum antioxidant capacity becomes complicated by the different methods used in detecting these changes. The interpretation also depends upon the conditions under which the antioxidant capacity is determined because the measurement reflects outcomes in a dynamic system. An increased antioxidant capacity in plasma or serum may not necessarily be a desirable condition if it reflects a response to increased oxidative stress. Similarly, a decrease in plasma or serum antioxidant capacity may not necessarily be an undesirable condition if the measurement reflects decreased production of reactive species. Because of these complications, no single measurement of antioxidant status is going to be sufficient, but a "battery" of measurements, many of which will be described in Forum articles, will be necessary to adequately assess oxidative stress in biological systems.

Analysis of the human carcinoembryonic antigen promoter core region in colorectal carcinoma-selective cytosine deaminase gene therapy

We isolated a 204-base pair carcinoembryonic antigen (CEA) promoter core region from a CEA-producing human colorectal carcinoma (CRC) and constructed retrovirus vectors carrying the expression cassette consisting of the CEA promoter core region and the cytosine deaminase (CD) gene. pCD2 retrovirus carrying the CD gene directed by the retrovirus long terminal repeat promoter served as a control vector. An in vitro study showed that the CEA promoter conferred CEA-producing cell-selective CD expression, specifically when the CD expression cassette was inserted into the 3' long terminal repeat of the retrovirus vector. CD-modified CRC xenografts in nude mice were sensitive to 5-fluorocytosine and caused a profound bystander effect on the unmodified CRC. When nude mice harboring intraperitoneally disseminated CRCs were injected intraperitoneally with the CD expression cassette-carrying retrovirus-producing cells, CD transduction into the disseminated CRCs and bone marrow (BM) was observed. CD expression was, however, restricted to CRCs, and it was observed in both CRCs and BM of mice injected with pCD2 retrovirus-producing cells, resulting in better therapeutic outcomes without BM suppression. These results indicate that effective and safe in vivo gene therapy for CRC may be feasible by transferring the CD gene controlled by the CEA promoter core region.

HPLC method for the quantification of procyanidins in cocoa and chocolate samples and correlation to total antioxidant capacity

Monomeric and oligomeric procyanidins present in cocoa liquors and chocolates were separated and quantified in four different laboratories using a normal-phase high-performance liquid chromatography (HPLC) method with fluorescence detection. Procyanidin standards through decamers were obtained by extraction from cocoa beans, enrichment by Sephadex LH-20 gel permeation chromatography, and final purification by preparative normal-phase HPLC. The purity of each oligomeric fraction was assessed using HPLC coupled to mass spectrometry. A composite standard was then prepared, and calibration curves were generated for each oligomeric class using a quadratic fit of area sum versus concentration. Results obtained by each of the laboratories were in close agreement, which suggests this method is reliable and reproducible for quantification of procyanidins. Furthermore, the procyanidin content of the samples was correlated to the antioxidant capacity measured using the ORAC assay as an indicator for potential biological activity.

Developmental and hormonal regulation of murine scavenger receptor, class B, type 1

The scavenger receptor, class B, type I (SR-BI), is the predominant receptor that supplies plasma cholesterol to steroidogenic tissues in rodents. We showed previously that steroidogenic factor-1 (SF-1) binds a sequence in the human SR-BI promoter whose integrity is required for high-level SR-BI expression in cultured adrenocortical tumor cells. We now provide in vivo evidence that SF-1 regulates SR-BI. During mouse embryogenesis, SR-BI mRNA was initially expressed in the genital ridge of both sexes and persisted in the developing testes but not ovary. This sexually dimorphic expression profile of SR-BI expression in the gonads mirrors that of SF-1. No SR-BI mRNA was detected in the gonadal ridge of day 11.5 SF-1 knockout embryos. Both SR-BI and SF-1 mRNA were expressed in the cortical cells of the nascent adrenal glands. These studies directly support SF-1 participating in the regulation of SR-BI in vivo. We examined the effect of cAMP on SR-BI mRNA and protein in mouse adrenocortical (Y1-BS1) and testicular carcinoma Leydig (MA-10) cells. The time courses of induction were strikingly similar to those described for other cAMP- and SF-1-regulated genes. Addition of lipoproteins reduced SR-BI expression in Y1-BS1 cells, an effect that was reversed by administration of cAMP analogs. SR-BI mRNA and protein were expressed at high levels in the adrenal glands of knockout mice lacking the steroidogenic acute regulatory protein; these mice have extensive lipid deposits in the adrenocortical cells and high circulating levels of ACTH. Taken together, these studies suggest that trophic hormones can override the suppressive effect of cholesterol on SR-BI expression, thus ensuring that steroidogenesis is maintained during stress.

Proton magnetic resonance spectroscopy of late delayed radiation-induced injury of the brain

We prospectively evaluated metabolite changes in late delayed radiation-induced injury to the temporal lobes on proton ((1)H) magnetic resonance spectroscopy (MRS) in 34 patients. Morphologically more severe injury on imaging tended to have lower N-acetyl aspartate (NAA)/creatine (Cr) and NAA/choline (Cho) ratios. A significantly higher Cho/Cr ratio was found in the most severe grade of cerebral necrosis, in which lactate might be present. The progressive decrease in NAA with increasing severity reflected neuronal loss at different stages of late delayed radiation-induced brain injury. The absence of Cho elevation in mild and moderate lesions did not suggest demyelination or glial hyperplasia as an etiologic mechanism of late delayed radiation-induced brain injury. The association of severe morphologic lesions with elevated lactate suggests ischemia as the underlying mechanism for severe lesions. (1)H MRS may provide metabolite information conducive to the understanding of the pathophysiology of late radiation-induced brain injury. J. Magn. Reson. Imaging 1999;10:130-137.

In vivo gene transfer of a suicide gene under the transcriptional control of the carcinoembryonic antigen promoter results in bone marrow transduction but can avoid bone marrow suppression

We constructed the CEA419/CD retrovirus vector carrying the cytosine deaminase (CD) gene directed by the carcinoembryonic antigen (CEA) promoter. pCD2 retrovirus vector carrying the CD gene directed by the retrovirus long terminal repeat promoter was also used. When mice bearing intraperitoneally disseminated colorectal carcinomas (CRCs) were infused intraperitoneally with pCD2 or CEA419/CD retrovirus-producing cells, a CD fragment was detected in CRCs and bone marrow cells. It was shown that the CD gene was expressed both in CRCs and in the bone marrow of animals infused with pCD2 retrovirus-producing cells, while the CD gene was expressed solely in CRCs of animals infused with CEA419/CD retrovirus-producing cells. These results indicate that the use of a tumor-selective promoter may warrant the safety of in vivo gene therapy using suicide genes.

Black-white differences in disability and morbidity in the last years of life

To assess black-white differences in disability and morbidity in the last years of life, the authors analyzed data from the National Health Interview Survey from 1986 to 1994, with mortality follow-up through December 1995. A baseline household interview was conducted for 10,187 decedents aged 50 years and over within 2 years before death. Data collected included long-term limitation of activity, number of chronic conditions, number of bed days, doctor visits, and days of short hospital stay during the year preceding the interview. For both blacks and whites, educational attainment was inversely associated with disability/morbidity indices. Black decedents had greater morbidity compared with whites, and this difference was consistent across educational levels. Adjustment for education reduced the black-white difference in limitation of activity score by 32%, bed days by 59%, and hospital stay days by 40%. This study from a national representative US sample indicates that black decedents experienced greater disability/morbidity and worse quality of life through their last few months or years of life. Educational attainment was associated with morbidity before death and accounted for much of the black-white difference.

Hyperoxia-induced changes in antioxidant capacity and the effect of dietary antioxidants

We investigated, by measuring oxygen radical absorbance capacity (ORAC), whether hyperoxia causes alterations in antioxidant status and whether these alterations could be modulated by dietary antioxidants. Rats were fed for 8 wk a control diet or a control diet supplemented with vitamin E (500 IU/kg) or with aqueous extracts (ORAC: 1.36 mmol Trolox equivalents/kg) from blueberries or spinach and then were exposed to air or >99% O2 for 48 h. Although the constituents of the extracts were not extensively characterized, HPLC indicated that blueberry extract was particularly rich in anthocyanins, and the spinach extract did not contain any anthocyanins. The ORAC was determined in samples without proteins [serum treated with perchloric acid (PCA); ORACPCA] and with proteins (ORACtot). Hyperoxia induced a decrease in serum protein concentration, an increase in serum ORACPCA, decreases in lung ORACPCA and ORACtot, and an equilibration of proteins and ORACPCA between serum and pleural effusion. These alterations suggested a redistribution of antioxidants between tissues and an increase in capillary permeability during hyperoxia. Only the blueberry extract was effective in alleviating the hyperoxia-induced redistribution of antioxidants between tissues.

Socioeconomic status and morbidity in the last years of life

OBJECTIVES

This study evaluated the effect of socioeconomic status, as characterized by level of education, on morbidity and disability in the last years of life.

METHODS

The analysis used data from the National Health Interview Survey (1986-1990), with mortality follow-up through December 1991.

RESULTS

Among 10,932 decedents 50 years or older at baseline interview, educational attainment was inversely associated with long-term limitation of activity, number of chronic conditions, number of bed days, and days of short hospital stay during the year preceding the interview.

CONCLUSIONS

Decedents with higher socioeconomic status experienced lower morbidity and disability and better quality of life even in their last years of life.

Antioxidant capacity and polyphenolic components of teas: implications for altering in vivo antioxidant status

The Oxygen Radical Absorbance Capacity (ORAC) assay was used to determine the total antioxidant capacity of tea. Green and black teas (n = 18) had a mean antioxidant capacity of 761.1 +/- 85.3 micromol Trolox Equivalents (TE) per g dry matter. However, their antioxidant capacity varied from 235 micromol to over 1526 micromol Trolox equivalents (TE)/g dry matter, and total phenolics ranged from 32 to 147 mg/g in different commercial teas. One tea phenolics extract had an antioxidant capacity of 4796 micromol TE/g dry matter and 625 mg total phenolics/g. On a dry matter basis, an antioxidant capacity of 761 micromol TE/g is considerably higher than any of the other fruits and vegetables measured in our laboratory. However, since dry tea is not consumed directly, brewing conditions may influence the final antioxidant capacity in the tea as consumed. We tested both green and black teas by placing one tea bag (1.95 g) in 150 ml (5 oz.) of boiling water. In the first brewed cup, approximately 84% of the total antioxidant activity was solubilized within the first 5 min of brewing. An additional 13% of the antioxidant activity was extracted into the second glass of 150 ml with an additional 5 min of brewing. At the dilutions obtained after the first brewing, the tea as consumed would contain approximately 8. 31 micromol TE per ml. This total antioxidant capacity compares to other drinks from fruits and vegetables that had antioxidant capacity values ranging from 1.6 to 15 micromol TE/ml. At these antioxidant levels, consumption of 150 ml of tea could make a significant contribution to the total daily antioxidant capacity intake. (-)-Epicatechin and (+)-catechin, two components from tea, had an antioxidant capacity of 2.36 and 2.49 micromol/micromol or 8. 13 and 8.58 micromol/mg, respectively. In 16 tea samples we observed a mean of 10.0 +/- 0.6 micromol TE/mg total phenolics. Tea can be an important source of what has been referred to as "non-nutrient" antioxidant phytochemicals. However, with the variation that exists in antioxidant capacity with various tea preparations, measures of antioxidant capacity intake are critical to the study of intake and health outcomes and/or biomarkers of health outcomes.

Maximum-likelihood generalized heritability estimate for blood pressure in Nigerian families

Elevated blood pressure (BP) is more common in relatives of hypertensives than in relatives of normotensives, indicating familial resemblance of the BP phenotypes. Most published studies have been conducted in westernized societies. To assess the ability to generalize these estimates, we examined familial patterns of BP in a population-based sample of 510 nuclear families, including 1552 individuals (320 fathers, 370 mothers, 475 sons, and 387 daughters) from Ibadan, Nigeria. The prevalence of obesity in this community is low (body mass index: fathers, 21.6; mothers, 23.6; sons, 19.2; and daughters=21.0 kg/m2). The BP phenotype used in all analyses was created from the best regression model by standardizing the age-adjusted systolic blood pressure (SBP) and diastolic blood pressure (DBP) to 0 mean and unit variance. Heritability was estimated by use of the computer program SEGPATH from the most parsimonious model of "no spouse and neither gender nor generation difference" as 45% for SBP and 43% for DBP. The lack of a significant spouse correlation is consistent with little or no influence of the common familial environment. However, the heritability estimate of <50% for both SBP and DBPs reinforces the importance of the nonshared environmental effect.

A safe, effective in vivo gene therapy for melanoma using tyrosinase promoter-driven cytosine deaminase gene

This study was designed to develop a safe, effective gene therapy for disseminated melanoma. We constructed retroviral vectors containing a tyrosinase promoter-cytosine deaminase expression cassette (Tyr/CD), and demonstrated that the tyrosinase promoter conferred a selective expression of cytosine deaminase (CD) gene in B16 melanoma cells, especially when the Tyr/CD cassette inserted in 3'LTR region of a retroviral vector. In vivo gene therapy for the intraperitoneally disseminated melanoma using Tyr/CD retrovirus-producing cells and 5-fluorocytosine (5-FC) showed that retroviruses produced in situ were capable of infecting tumor xenografts and bone marrow cells in animal model, and survival rates were prolonged significantly as compared with those treated with CD2 retrovirus-producing cells and 5-FC. Importantly, the treatment-related bone marrow suppression was not observed in the former treatment, while profound bone marrow suppression was observed in the latter treatment. In vivo gene therapy using retrovirus-producing cells containing suicide gene under the control of a tissue-specific promoter and 5-FC administration is safer and more effective for the treatment of disseminated melanoma, as compared with retrovirus-producing cells containing the gene under the control of a universal promoter and 5-FC.

Self-reported health status and mortality in a multiethnic US cohort

The authors examined the relation between self-reported health status and mortality among the following racial/ethnic groups: Native Americans, Asian/Pacific Islanders, blacks, whites, and Hispanics. They pooled 1986-1994 data from the National Health Interview Survey to obtain information on more than 700,000 cohort participants. Although fewer than 5,000 Native Americans are included in this cohort, the data provide information previously unavailable for this group. Also included are almost 17,000 Asian/Pacific Islanders, over 90,000 blacks, and over 50,000 Hispanics. The authors found strong associations between self-reported health status and both socioeconomic status and subsequent mortality. A self-report of fair or poor health was associated with at least a twofold increased risk of mortality for all racial/ethnic groups. Even after adjustment for socioeconomic status and measures of comorbidity, a significant relation was found between self-reported health status and subsequent mortality. The authors found that self-reported health status is a strong prognostic indicator for subsequent mortality for both genders and all racial/ethnic groups examined. These results emphasize the utility of using simple filter questions in population research.

Effective and safe gene therapy for colorectal carcinoma using the cytosine deaminase gene directed by the carcinoembryonic antigen promoter

We have recently isolated carcinoembryonic antigen (CEA) promoter regions consisting of 419 bp and 204 bp from CEA-producing human colorectal carcinoma (CRC). We constructed CEA419/CD and CEA204/CD retroviruses carrying the bacterial cytosine deaminase (CD) gene directed by the CEA promoter regions. pCD2 retroviruses carrying the CD gene directed by the retrovirus long terminal repeat promoter were also used. CEA419/CD or CEA204/CD retrovirus-infected CRC cells were found to be susceptible to 5-fluorocytosine (5-FC), while non-CRC cells infected with the same retroviruses were not. CD-transduced CRC xenografts in nude mice were sensitive to 5-FC treatment, resulting in arrest of tumor growth. When mice with intraperitoneally disseminated CRCs were given intraperitoneal injections of CEA419/CD retrovirus-producing cells followed by 5-FC treatment, significantly prolonged survival rates were observed compared with animals injected with pCD2 retrovirus-producing cells followed by 5-FC treatment. Importantly, bone marrow suppression was not observed in animals injected with CEA419/CD retrovirus-producing cells and 5-FC, while profound bone marrow suppression was observed in those injected with pCD2 retrovirus-producing cells and 5-FC. These results indicate that effective and safe in vivo gene therapy for advanced CRC may be feasible by transferring the CD gene controlled by the CEA promoter followed by 5-FC treatment.

[Enhancement of apoptotic sensitivity induced by UV irradiation on the p53-transducted K562 cells]

OBJECTIVE

To answer whether wild-type p53 can sensitize K562 cell apoptosis induced by UV irradiation.

METHODS

K562 cells transducted with retrovirus encoding wild-type p53 were irradiated by ultraviolet for different time and then cultured for different time. Apoptosis was detected by TDT end labelling technique, DNA fragmentation and MTT assay.

RESULTS

TDT end labelling and DNA fragmentation showed that apoptosis induced by 8 min UV-irradiation differed significantly between K562-neo and K562-p53 cells.

CONCLUSION

Wild-type p53 can enhance apoptosis induced by UV-irradiation on K562 cells.

Serum antioxidant capacity is increased by consumption of strawberries, spinach, red wine or vitamin C in elderly women

It is often assumed that antioxidant nutrients contribute to the protection afforded by fruits, vegetables, and red wine against diseases of aging. However, the effect of fruit, vegetable and red wine consumption on the overall antioxidant status in human is unclear. In this study we investigated the responses in serum total antioxidant capacity following comsumption of strawberries (240 g), spinach (294 g), red wine (300 ml) or vitamin C (1250 mg) in eight elderly women. Total antioxidant capacity was determined using different methods: oxygen radical absorbance capacity (ORAC) assay, Trolox equivalent antioxidant capacity (TEAC) assay and ferric reducing ability (FRAP) assay. The results showed that the total antioxidant capacity of serum determined as ORAC, TEAC and FRAP, using the area under the curve, increased significantly by 7-25% during the 4-h period following consumption of red wine, strawberries, vitamin C or spinach. The total antioxidant capacity of urine determined as ORAC increased (P < 0.05) by 9.6, 27.5, and 44.9% for strawberries, spinach, and vitamin C, respectively, during the 24-h period following these treatments. The plasma vitamin C level after the strawberry drink, and the serum urate level after the strawberry and spinach treatments, also increased significantly. However, the increased vitamin C and urate levels could not fully account for the increased total antioxidant capacity in serum following the consumption of strawberries, spinach or red wine. We conclude that the consumption of strawberries, spinach or red wine, which are rich in antioxidant phenolic compounds, can increase the serum antioxidant capacity in humans. J. Nutr. 2383-2390, 1998

Postprandial plasma carotenoid responses following consumption of strawberries, red wine, vitamin C or spinach by elderly women

This study investigated the postprandial plasma responses of carotenoids for 24 h after feeding five specific breakfast beverages; four of which had low or no carotenoid content. In seven fasting healthy elderly female subjects a blood sample (baseline) was obtained, after which they were given a breakfast beverage, containing one of the following: 1) strawberries (240 g); 2) ascorbic acid (1250 mg); 3) spinach (294 g); 4) red wine (300 mL); and 5) control (breakfast beverage only). Blood samples were collected at 0.5, 1, 4, 7, 11, 15 and 24 h. Plasma carotenoids were measured using HPLC. No significant differences were found in the levels of the plasma carotenoids measured among the various treatments at baseline. In the spinach treatment, plasma lutein, zeaxanthin and beta-carotene levels at 7, 11, 15 and 24 h were significantly higher than those at baseline, as expected. All of the carotenoids measured in the control and vitamin C treatments, at subsequent sampling times were not significantly different from those at baseline. However, for most carotenoids, strawberry and red wine feeding resulted in significantly lower carotenoids values from baseline at 11 and 15 h. Subjects who received a diet with low levels of carotenoids, but whose postprandial plasma levels of carotenoids remain steady, might be explained by a mechanism that promotes secretion of carotenoids into the circulation. Assuming that plasma carotenoids are being used over time, we hypothesize that strawberries and red wine contain some substances that interfere with the secretion of carotenoids into the circulation.

Membrane and receptor modifications of oxidative stress vulnerability in aging. Nutritional considerations

Evidence suggests that oxidative stress (OS) may contribute to the pathogenesis of age-related decrements in neuronal function and that OS vulnerability increases as a function of age. In addition to decreased endogenous protection, increases in OS vulnerability may result from changes in membrane lipids and distribution of receptor subtype. Using a PC-12 cell model system, we have shown that H2O2 or dopamine (DA) exposure induced deficits in the cell's ability to clear (extrude/sequester, E/S) Ca2+ that are similar to those seen in aging. When plasma membrane concentrations of sphingomyelin (SPM) were used, the SPM metabolite, sphingosine-1-phosphate was increased to the same levels as those seen in aging, and enhancement of OS-induced decreases in calcium E/S following KCL depolarization was observed. Differential decreases in CA2+ E/S were also seen following DA-induced OS in COS-7 cells transfected with one of five muscarinic receptor subtypes. Cells transfected with either M1, M2, or M4 receptors showed significantly greater vulnerability to OS (as expressed by greater decrements in calcium E/S and cell death) than those transfected with M3 or M5 receptors. The vitamin E analogue, Trolox, and the nitrone-trapping agent, PBN, were not effective in altering E/S decrements but were effective in preventing cell death 24 h after OS exposure. These findings suggest that putative regional (e.g., striatum and hippocampus) increases in OS vulnerability and loss of neuronal function in aging may be dependent upon membrane SPM concentration and receptor subtype. In related studies, attempts were made to determine whether increased OS protection via nutritional increases in antioxidant levels in rats [using diets supplemented with vitamin E (500IU/kg), strawberry extracts (9.4 g/kg dried aqueous extract, DAE), spinach (6.7 g/kg DAE), or blueberry extracts (10 g/kg DEA for six weeks)] would protect against exposure to 100% O2 (a model of accelerated neuronal aging). Results indicated that these diets were effective in preventing OS-induced decrements in several parameters (e.g., nerve growth factor decreases), suggesting that although there may be increases in OS vulnerability in aging, phytochemicals present in antioxidant-rich foods may be beneficial in reducing or retarding the functional central nervous system deficits seen in aging or oxidative insult.

The effect of long-term dietary supplementation with antioxidants

The impact of diet and specific food groups on aging and age-associated degenerative diseases has been widely recognized in recent years. The modern concept of the free radical theory of aging takes as its basis a shift in the antioxidant/prooxidant balance that leads to increased oxidative stress, dysregulation of cellular function, and aging. In the context of this theory, antioxidants can influence the primary "intrinsic" aging process as well as several secondary age-associated pathological processes. For the latter, several epidemiological and clinical studies have revealed potential roles for dietary antioxidants in the age-associated decline of immune function and the reduction of risk of morbidity and mortality from cancer and heart disease. We reported that long-term supplementation with vitamin E enhances immune function in aged animals and elderly subjects. We have also found that the beneficial effect of vitamin E in the reduction of risk of atherosclerosis is, in part, associated with molecular modulation of the interaction of immune and endothelial cells. Even though the effects of dietary antioxidants on aging have been mostly observed in relation to age-associated diseases, the effects cannot be totally separated from those related to the intrinsic aging process. For modulation of the aging process by antioxidants, earlier reports have indicated that antioxidant feeding increased the median life span of mice to some extent. To further delineate the effect of dietary antioxidants on aging and longevity, middle-aged (18 mo) C57BL/6NIA male mice were fed ad libitum semisynthetic AIN-76 diets supplemented with different antioxidants (vitamin E, glutathione, melatonin, and strawberry extract). We found that dietary antioxidants had no effect on the pathological outcome or on mean and maximum life span of the mice, which was observed despite the reduced level of lipid peroxidation products, 4-hydroxynonenol, in the liver of animals supplemented with vitamin E and strawberry extract (1.34 +/- 0.4 and 1.6 +/- 0.5 nmol/g, respectively) compared to animals fed the control diet (2.35 +/- 1.4 nmol/g). However, vitamin E-supplemented mice had significantly lower lung viral levels following influenza infection, a viral challenge associated with oxidative stress. These and other observations indicate that, at present, the effects of dietary antioxidants are mainly demonstrated in connection with age-associated diseases in which oxidative stress appears to be intimately involved. Further studies are needed to determine the effect of antioxidant supplementation on longevity in the context of moderate caloric restriction.

Scavenger receptor, class B, type I-dependent stimulation of cholesterol esterification by high density lipoproteins, low density lipoproteins, and nonlipoprotein cholesterol

Scavenger receptor, class B, type I (SR-BI) is a cell surface glycoprotein that mediates selective uptake and efflux of sterols from high density lipoproteins (HDL) to cells. A Chinese hamster ovary cell line that is deficient in functional LDL receptors, but has high expression levels of recombinant SR-BI (ldlA7-SR-BI), was used to examine the effect of SR-BI on the trafficking of sterols between lipoproteins and cells. To monitor the fate of sterols transported by SR-BI into cells, we measured the incorporation of [14C]oleate into cholesterol esters by acyl-CoA:cholesteryl acyltransferase in the endoplasmic reticulum. We show that incubation of ldlA7-SRBI cells with either LDL or HDL resulted in an equally dramatic increase in the formation of [14C]oleate-labeled cholesterol esters. The lipoprotein-stimulated, SR-BI-dependent increase in cholesterol esterification was inhibited by chloroquine. The uptake of sterols and their incorporation into cholesterol esters by SR-BI from LDL was largely a selective process. The addition of free cholesterol to ldlA7-SRBI cells also stimulated cholesterol ester formation in a chloroquine-sensitive fashion. We also show that SR-BI mediates the efflux of endogenously synthesized sterols from the cell membrane. From these studies we conclude that, in the absence of the LDL receptor, overexpression of SR-BI can mediate significant transport of sterols between lipoproteins and the endoplasmic reticulum of cells.

Increases in human plasma antioxidant capacity after consumption of controlled diets high in fruit and vegetables

BACKGROUND

The putative beneficial effects of an increased consumption of fruit and vegetables have been associated with antioxidant nutrients. However, the effect of fruit and vegetable consumption on the overall antioxidant status in humans is unclear.

OBJECTIVE

The objective of this study was to investigate whether a diet rich in fruit and vegetables would affect the antioxidant capacity of human plasma.

DESIGN

Thirty-six healthy nonsmokers resided in a metabolic research unit and consumed 2 sets of controlled diets. Diet A contained 10 servings of fruit and vegetables each day for 15 d. Diet B was the same as diet A, except diet B also provided 2 servings of broccoli each day on days 6-10. There was a free-living period of a minimum of 6 wk between the 2 experiments using either diet A or diet B. Fasting plasma antioxidant capacity, measured as oxygen radical absorbance capacity (ORAC), and alpha-tocopherol concentrations were determined on days 1, 6, 11, and 16.

RESULTS

The fasting baseline plasma ORAC of these subjects was significantly correlated with their estimated daily intake of total antioxidants from fruit and vegetables during the previous year. Plasma ORAC of these subjects was significantly increased by both diets A and B. This increase in ORAC could not be explained by the increase in the plasma alpha-tocopherol concentration.

CONCLUSION

Increased consumption of fruit and vegetables can increase the plasma antioxidant capacity in humans.

Pharmacokinetic interaction between ritonavir and indinavir in healthy volunteers

The pharmacokinetic interaction between indinavir and ritonavir was evaluated in five groups of healthy adult volunteers to explore the potential for twice-daily (b.i.d.) dosing of this combination. All subjects received 800 mg of indinavir every 8 h (q8h) on day 2. In addition, subjects in group I received one dose of 800 mg of indinavir on day 1 and 800 mg of indinavir q8h on day 17. Subjects in Groups II and IV each received one dose of 600 mg of indinavir on days 1 and 17, and subjects in groups III and V each received one dose of 400 mg of indinavir on days 1 and 17. During days 3 to 17, ritonavir placebo or ritonavir at 200, 300, 300, or 400 mg q12h was given to groups I, II, III, IV, and V, respectively. Ritonavir at steady state probably inhibited the cytochrome P-450 3A metabolism of indinavir and substantially increased plasma indinavir concentrations, with the area under the plasma concentration-time curve (AUC) increasing up to 475% and the peak concentration in serum (Cmax) increasing up to 110%. The Cmax/trough concentration ratio decreased from 50 in standard q8h regimens to less than 14 when indinavir was administered with ritonavir. For a constant indinavir dose, an increase in the ritonavir dose yielded similar indinavir AUCs, Cmaxs, and concentrations at 12 h (C12s). For a constant ritonavir dose, an increase in the indinavir dose resulted in approximately proportional increases in the indinavir AUC, less than proportional increases in Cmax, and slightly more than proportional increases in C12. Ritonavir reduced between-subject variability in the indinavir AUC and trough concentrations and did not affect indinavir renal clearance. With the altered pharmacokinetic profile, indinavir likely could be given as a b.i.d. combination regimen with ritonavir. This could potentially improve patient compliance and thereby reduce treatment failures.

Comparison of carcinoembryonic antigen promoter regions isolated from human colorectal carcinoma and normal adjacent mucosa to induce strong tumor-selective gene expression

To establish in vivo gene therapy against cancer, it is requisite to induce strong, cancer cell-selective expression of a therapeutic gene. Comparison of the promoter activity of 5' flanking regions of the carcinoembryonic antigen (CEA) gene isolated from various origins is therefore of considerable interest. The 5' flanking region of the CEA gene between -135 and +69 bp upstream from the transcriptional start site, which is recognized as the core promoter region, was isolated from CEA-producing human colorectal carcinoma (CRC), normal adjacent mucosa, CEA-producing cell lines and CEA-non-producing cell lines. No mutations were observed by single-strand conformation polymorphism in the CEA promoter regions. Subsequent sequence analysis revealed that there were no mutations in the CEA promoter regions isolated from CEA-producing CRC and normal adjacent mucosa. Furthermore, nuclear extracts prepared from CEA-producing human CRC cells could equally bind to both the CEA promoter fragments isolated from CEA-producing CRC and normal mucosa. Both CEA promoter regions could direct 5- to 20-fold higher expression of a luciferase reporter gene in CEA-producing cells than in CEA-non-producing cells. Therefore, we suggest that the use of either CEA promoter region isolated from CRC or normal mucosa is equally effective to induce strong, CEA-producing cancer-selective expression of a therapeutic gene.

Comparison of carcinoembryonic antigen promoter regions isolated from human colorectal carcinoma and normal adjacent mucosa to induce strong tumor-selective gene expression

To establish in vivo gene therapy against cancer, it is requisite to induce strong, cancer cell-selective expression of a therapeutic gene. Comparison of the promoter activity of 5' flanking regions of the carcinoembryonic antigen (CEA) gene isolated from various origins is therefore of considerable interest. The 5' flanking region of the CEA gene between -135 and +69 bp upstream from the transcriptional start site, which is recognized as the core promoter region, was isolated from CEA-producing human colorectal carcinoma (CRC), normal adjacent mucosa, CEA-producing cell lines and CEA-non-producing cell lines. No mutations were observed by single-strand conformation polymorphism in the CEA promoter regions. Subsequent sequence analysis revealed that there were no mutations in the CEA promoter regions isolated from CEA-producing CRC and normal adjacent mucosa. Furthermore, nuclear extracts prepared from CEA-producing human CRC cells could equally bind to both the CEA promoter fragments isolated from CEA-producing CRC and normal mucosa. Both CEA promoter regions could direct 5- to 20-fold higher expression of a luciferase reporter gene in CEA-producing cells than in CEA-non-producing cells. Therefore, we suggest that the use of either CEA promoter region isolated from CRC or normal mucosa is equally effective to induce strong, CEA-producing cancer-selective expression of a therapeutic gene.

Long-term dietary strawberry, spinach, or vitamin E supplementation retards the onset of age-related neuronal signal-transduction and cognitive behavioral deficits

Recent research has indicated that increased vulnerability to oxidative stress may be the major factor involved in CNS functional declines in aging and age-related neurodegenerative diseases, and that antioxidants, e.g., vitamin E, may ameliorate or prevent these declines. Present studies examined whether long-term feeding of Fischer 344 rats, beginning when the rats were 6 months of age and continuing for 8 months, with diets supplemented with a fruit or vegetable extract identified as being high in antioxidant activity, could prevent the age-related induction of receptor-mediated signal transduction deficits that might have a behavioral component. Thus, the following parameters were examined: (1) oxotremorine-enhanced striatal dopamine release (OX-K+-ERDA), (2) cerebellar beta receptor augmentation of GABA responding, (3) striatal synaptosomal 45Ca2+ clearance, (4) carbachol-stimulated GTPase activity, and (5) Morris water maze performance. The rats were given control diets or those supplemented with strawberry extracts (SE), 9.5 gm/kg dried aqueous extract (DAE), spinach (SPN 6.4 gm/kg DAE), or vitamin E (500 IU/kg). Results indicated that SPN-fed rats demonstrated the greatest retardation of age-effects on all parameters except GTPase activity, on which SE had the greatest effect, whereas SE and vitamin E showed significant but equal protection against these age-induced deficits on the other parameters. For example, OX-K+-ERDA enhancement was four times greater in the SPN group than in controls. Thus, phytochemicals present in antioxidant-rich foods such as spinach may be beneficial in retarding functional age-related CNS and cognitive behavioral deficits and, perhaps, may have some benefit in neurodegenerative disease.

[Enhancement of Vp16 inducing apoptosis of leukemic cells by retrovirus-mediated bcl-2 anti-sense RNA]

OBJECTIVE

To explore the effects of retrovirus-mediated bcl-2 antisense RNA on apoptosis of leukemic cells.

METHODS

Retrovirus was packaged in vitro with PA317 cells and Jurkat cell was transducted with collected virus; The expressions of bcl-2 mRNA and protein were assayed by RT-PCR and Western blotting, respectively. Apoptosis was assayed by flow cytometry and DNA "ladder".

RESULTS

Expression of intrinsic bcl-2 was decreased, and the sensitivity of leukemic cells to Vp16 and the apoptosis of leukemic cells line Jurkat cells were enhanced by transfected bcl-2 antisense RNA.

CONCLUSION

Antisense bcl-2 enhances Vp16 inducing apoptosis of leukemic cells. The results provide a useful experimental basis for leukemia therapy.

Age-related neurodegeneration and oxidative stress: putative nutritional intervention

This review describes age-related changes that occur in neuronal function and cites evidence to show that these alterations may be the result of increased sensitivity to oxidative stress (OS). Evidence is presented to show that the abilities to mitigate the OS effects and to repair the damage from OS show decline as a function of age. Results from age- and OS-sensitive tests are given; these results indicate that one of the major sites of action of OS is the membranes, especially if compromised by high amounts of sphingomyelin, and one of the major effects of OS is to further alter the calcium disregulation in aging. It is suggested that attempts to increase antioxidant protection through diets comprised of fruits and vegetables identified as being high in total antioxidant activity might prevent or reverse the deleterious OS effects on neuronal aging.

Disease incidence and longevity are unaltered by dietary antioxidant supplementation initiated during middle age in C57BL/6 mice

The ability of augmented antioxidant consumption to alter disease incidence, lesion burden and/or longevity was studied in adult male C57BL/6 mice. Mice were fed modified AIN76 diet or modified AIN76 supplemented with vitamin E, glutathione (GSH), vitamin E and GSH, melatonin or strawberry extract starting at 18 months of age. All the mice in this study were heavier than reference populations of male C57BL/6 mice fed NIH-07 or NIH-31, which were maintained without a mid-life change in diet. Fatty liver, focal kidney atrophy and proteinacious casts in the renal tubules were observed more frequently in this study population than in the reference populations. Lesion burden and incidence of specific lesions observed amongst the various groups in this study did not differ. There were no differences observed for longevity of any of the study groups. The longevity observed in this study was similar to that previously reported for male C57BL/6 mice. Thus, diet supplementation with antioxidants initiated during middle age did not appear to affect age-associated lesions patterns, lesion burden or longevity for ad libitum fed male C57BL/6 mice.

Comparison of different analytical methods for assessing total antioxidant capacity of human serum

Three assays were compared for the determination of total antioxidant capacity in human serum: the oxygen radical absorbance capacity (ORAC) assay, the Randox Trolox-equivalent antioxidant capacity (Randox-TEAC) assay, and the ferric reducing ability (FRAP) assay. There was a weak but significant linear correlation between serum ORAC and serum FRAP. There was no correlation either between serum ORAC and serum TEAC or between serum FRAP and serum TEAC. The effect of dilution on the serum TEAC value and the use of inhibition percentage at a fixed time, without considering the length of inhibition time in the quantitation of results, adversely affected the Randox-TEAC assay. The FRAP assay is simple and inexpensive but does not measure the SH-group-containing antioxidants. The ORAC assay has high specificity and responds to numerous antioxidants. By utilizing different extraction techniques in the ORAC assay, one can remove serum proteins and also make some gross differentiation between aqueous and lipid-soluble antioxidants. However, the ORAC assay requires approximately 60 min more than the FRAP or Randox-TEAC assay to quantitate results.

[Endovascular exclusion of abdominal aortic aneurysm]

OBJECTIVE

To explore the indications, methods, manipulations, and problems of endovascular exclusion of abdominal aortic aneurysm (AAA).

METHOD

Under general anesthesia and dynamic supervision of DSA, an endovascular exclusion with a stent-graft complex of 11.0 cm x 2.6 cm was successfully performed on a 70-year-old man contraindicated for major open surgery with AAA of 10.0 cm x 6.0 cm and an AAA neck of 2.5 cm x 1.6 cm.

RESULT

The patient was up and about on the first postoperative day. Duplex scan (by the end of the first postoperative week) and CT (on the postoperative 20th day) revealed a completely excluded AAA by the stent-graft that was patent and had an inner diameter of 2.2-2.4 cm, without migration and torsion. The primary AAA sac was full of thrombi and no patent lumbar and inferior mesenteric arteries were observed. The external diameter of AAA was unchanged, renal and iliac arteries were all patent, but a micro-crevice between the proximal end of the stent-graft and the anterior wall of the AAA neck was revealed. Six months postoperative follow-up showed that the patient's abdominal pulsatile mass and the left lower extremity's claudication disappeared.

CONCLUSION

Endovascular exclusion of AAA is of great practical value.

Pharmacokinetic interactions between two human immunodeficiency virus protease inhibitors, ritonavir and saquinavir

OBJECTIVE

To assess the pharmacokinetic interaction between ritonavir and saquinavir.

METHODS

Ritonavir and saquinavir were administered in single doses to six groups of healthy volunteers in a two-way (saquinavir alone and ritonavir plus saquinavir for groups I through V) and a three-way (ritonavir alone, saquinavir alone, and ritonavir plus saquinavir for group VI) crossover manner with the following doses: group I, 200 mg saquinavir and 300 mg ritonavir; group II, 200 mg saquinavir and 600 mg ritonavir; group III, 400 mg saquinavir and 300 mg ritonavir; group IV, 400 mg saquinavir and 600 mg ritonavir; group V; 600 mg saquinavir and 200 mg ritonavir; group VI, 600 mg saquinavir and 600 mg ritonavir.

RESULTS

Coadministration of ritonavir markedly increased the area under the plasma concentration-time curve (AUC) and peak concentration of saquinavir (> 50-fold and 22-fold, respectively). For a constant ritonavir dose, the pharmacokinetics of saquinavir were relatively proportional to dose. For a constant saquinavir dose, the increase in saquinavir concentration tended to be less than proportional to ritonavir dose. Ritonavir reduced intersubject variability in the saquinavir AUC from 60% to 28%. The in vivo inhibition constant was 0.025 +/- 0.020 micrograms/ml with noncompartmental estimation and 0.0164 +/- 0.0004 micrograms/ml with nonlinear mixed-effects model compartmental analysis. Saquinavir showed no clinically significant effect on the pharmacokinetics of ritonavir (+6.4% in AUC). The regimens were well tolerated.

CONCLUSIONS

The large effect of ritonavir on the pharmacokinetics of saquinavir is consistent with a large reduction of saquinavir first-pass metabolism and postabsorptive clearance. Given the limited bioavailability of saquinavir given in the hard gelatin capsule formulation, this drug interaction is expected to have implications in the use of protease inhibitors in the management of human immunodeficiency virus infection.

Lack of CYP3A inhibition effects of sertindole on terfenadine in healthy volunteers

The effect of sertindole (a new selective antipsychotic compound) on the pharmacokinetic disposition of terfenadine was investigated. Thirteen subjects who completed the study received a single 120 mg dose of terfenadine alone or with concomitant 20 mg sertindole daily. The mean values for terfenadine Cmax (alone: 2.42 +/- 1.48 ng/ml, in combination: 2.99 +/- 1.85 ng/ml) and AUC (29.6 +/- 18.9 vs 37.9 +/- 23.4 ng x hr/ml) did not change statistically significant in the presence of sertindole (p > 0.05). Similarly, the mean Cmax (531 +/- 195 vs 506 +/- 190 ng/ml) and AUC (3,728 +/- 1,163 vs 4,003 +/- 1,739 ng x hr/ml) values of carboxyterfenadine did not change statistically significant in the presence of sertindole (p > 0.05). The other pharmacokinetic parameters of terfenadine and carboxyterfenadine such as Tmax, t1/2, as well as the carboxyterfenadine to terfenadine Cmax and AUC ratios did not change in the presence of sertindole. Although terfenadine is a substrate for CYP3A (cytochrome P-450 3A), while sertindole is a substrate for both CYP2D6 and CYP3A4, the results in this study suggest that sertindole, at a clinical dose, is not an inhibitor of the metabolism of terfenadine.

Mortality patterns among adult Hispanics: findings from the NHIS, 1986 to 1990

OBJECTIVES

The purpose of this study was to assess the mortality pattern of the adult Hispanic population in the United States.

METHODS

This was a cohort study using data from the National Health Interview Survey from 1986 through 1990. Deaths were ascertained by matching the National Death Index through 1991.

RESULTS

This representative national sample included 297,640 non-Hispanic Whites, 53,552 Blacks, and 27,239 Hispanics, all aged 18 years or older at baseline. Different matching criteria resulted in modest differential estimates of the number of deaths by ethnic groups; these differences were quantitatively more important for Hispanics. Overall age-standardized mortality was lower among Hispanics. A prominent age by race interaction was apparent. The Hispanic: White mortality ratio was 1.33, 0.92, and 0.76 among men aged 18 through 44, 45 through 64, and 65 and older, respectively. Among women in the same age groups the Hispanic: White mortality ratio was 1.22, 0.75, and 0.70, respectively.

CONCLUSIONS

Longitudinal cohorts provide an important source of health status information on Hispanics. These results suggest that overall mortality is lower among Hispanics than among non-Hispanic Whites, especially in the oldest age group. Among younger and middle-aged persons, the mortality of Hispanics is similar to or even higher than that of Whites.

[A comparative study on transabdominal versus retroperitoneal approach for abdominal aortic surgery]

OBJECTIVE

To retrospectively compare transabdominal with retroperitoneal approach to the aorta for infrarenal aortic reconstruction.

METHODS

From January 1988 to December 1996, Patients undergoing surgery for abdominal aortic aneurysm (AAA) or aortoiliac occlusive disease (AIOD) were included in the retrospective comparison of transabdominal approach (TAA) with retroperitoneal approach (RPA) for aortic surgery. Forty-four patients were analyzed, with 26 (23 with AAA and 3 with AIOD) in TAA group and 18 (16 with AAA and 2 with AIOD) in RPA group. There were no significant differences between the groups in terms of age, sex, comorbid conditions, and vascular graft anastomoses.

RESULTS

The incidence of intraoperative complications was similar for both groups. Postoperatively, RPA group had significantly fewer overall complications than TAA group (P < 0.01). The incidence of prolonged ileus (6 cases in TAA group, none in RPA group) and small bowel obstruction (2 cases in TAA group, none in RPA group) was higher in the TAA group (P < 0.01). Postoperatively four deaths occurred with two in each group. There was no difference in pulmonary complications (P = 0.70). In long-term follow-up (mean 32 months), no significant difference was found in incisional hernias in the two groups.

CONCLUSIONS

RPA approach, with fewer postoperative complications, short stay in the hospital and intensive care unit, is a safer and simpler approach for abdominal aortic surgery.