Lisa Gualtieri

Survival of Lactobacillus species (strain GG) in human gastrointestinal tract

A newly isolated strain of a species ofLactobacillus of human origin, designated GG (Lactobacillus GG), has been studied to determine its ability to survive in the human gastrointestinal tract. When fed to 76 volunteers as a frozen concentrate or as a fermented preparation in milk or whey,Lactobacillus GG was recovered in the feces of all subjects receiving the fermented milk or whey and in 86% receiving the frozen concentrate when a single fecal specimen was cultured. The organism was also present in the feces of subjects concurrently receiving ampicillin. After terminating feeding of the organism,Lactobacillus GG persisted in the feces of 87% of volunteers four days later and in 33% of subjects seven days later.Lactobacillus GG lowered fecal bacterial β-glucuronidase activity by approximately 80% in volunteers given the organism for four weeks. These studies demonstrate thatLactobacillus GG can survive and temporarily colonize the human gastrointestinal tract and can affect the metabolic activity of the resident microflora.

The Internet as a Health Information Source: Findings from the 2007 Health Information National Trends Survey and Implications for Health Communication

A wealth of health information is available online, but we do not fully understand the implications for health communication. This study examined whether health information seekers who turn to the Internet first differ from those who turn elsewhere. Data from the 2,338 respondents to the mail portion of the National Cancer Institutes Health Information National Trends Survey (HINTS) 2007 who reported looking for health information for themselves were analyzed. Logistic regression was used to examine whether health information seekers turning to the Internet first differed in terms of demographics, information preferences and seeking confidence, and communication with providers from those using other sources. In the final model, Internet users were younger, more educated, higher income, preferred numbers rather than words to describe chance, and think it is very important to get personal medical information electronically. There were no differences in terms of gender, health status, confidence seeking health information, or communication with providers. Health information seekers who turn to the Internet first are different, both in terms of demographics and information preferences. As the use of communication technologies increases, health communicators need to be attentive to the potential for communication inequalities.

The effect of Lactobacillus GG on the initiation and promotion of DMH-induced intestinal tumors in the rat.

Male Fischer 344 rats were fed a 20% or a 5% corn oil diet and were injected subcutaneously with dimethylhydrazine (DMH) weekly for 16 weeks. In addition, an approximately equal number of animals challenged with DMH were fed daily, until the end of the study, 2 x 10(10) Lactobacillus casei subsp. rhamnosus strain GG starting three weeks before DMH administration or after the ninth weekly injection. The feeding of the Lactobacillus GG before and during carcinogen treatment resulted in a significant decrease in the incidence of colon tumors and the number of small intestinal and colon tumors per tumor-bearing animal for rats fed a 20% corn oil diet. This decrease in tumor incidence or number of tumors was not seen when animals were fed the Lactobacillus after the ninth week of carcinogen treatment. Animals fed a 5% corn oil diet had a lower tumor incidence and number of tumors resulting from the decrease in dietary fat; in addition the feeding of Lactobacillus GG before the carcinogen challenge resulted in a lower incidence of colon tumors. These studies show that a specific strain of L. casei subsp. rhamnosus designated GG can interfere with the initiation or early promotional stages of DMH-induced intestinal tumorigenesis, and this effect is most pronounced for animals fed a high-fat diet.

Effects of canola, corn, and olive oils on fasting and postprandial plasma lipoproteins in humans as part of a National Cholesterol Education Program Step 2 diet.

The most stringent dietary recommendations of the National Cholesterol Education Program (NCEP) are to limit fat intake to < 30% of calories, saturated fat intake to < 7% of calories, and cholesterol intake to < 200 mg/d (Step 2 diet). There is debate as to whether the remaining fat in the diet should be relatively high in monounsaturated or polyunsaturated fatty acids. We examined this issue by testing the effects of diets meeting the aforementioned guidelines that were enriched in three different vegetable oils on plasma lipids in the fasting and postprandial states in a clinically relevant population. Female and male subjects (n = 15, mean age, 61 years) with low-density lipoprotein cholesterol (LDL-C) concentrations > 130 mg/dL were studied under strictly controlled conditions. Subjects were first placed on a diet similar to that currently consumed in the United States to stabilize plasma lipids with respect to identical fat and cholesterol intakes. The subjects then received diets meeting NCEP Step 2 criteria in which two thirds of the fat calories were given either as canola, corn, or olive oil in a randomized, double-blinded fashion for 32 days each. Plasma cholesterol concentrations declined after consumption of diets enriched in all the test oils; however, the declines were significantly greater for the canola (12%) and corn (13%) than for the olive (7%) oil-enriched diet. Mean plasma LDL-C concentrations declined after consumption of diets enriched in all the test oils (16%, 17%, and 13% for canola, corn, and olive oil, respectively), and the magnitude of the declines was statistically indistinguishable among the test oils. Mean plasma high-density lipoprotein cholesterol (HDL-C) concentrations declined after consumption of the baseline diet, and these declines were significant for the canola (7%) and corn (9%) oil-enriched diets. Changes in LDL apolipoprotein (apo)B concentrations paralleled those of LDL-C. Switching from the baseline to the vegetable oil--enriched diets had no significant effect on plasma triglyceride, apoA-I, and lipoprotein(a) concentrations or the total cholesterol to HDL-C ratio. LDL apoB to apoA-I ratios were significantly reduced when the subjects consumed the vegetable oil--enriched diets. Differences similar to those observed in the fasting state were observed in the postprandial state.(ABSTRACT TRUNCATED AT 400 WORDS)

The effect of dietary fat and fiber on serum estrogen concentrations in premenopausal women under controlled dietary conditions.

The effect of dietary fiber and fat on serum sex hormones was studied in premenopausal women. After an initial control period during which the diet was high in fat (40% of calories as fat) and low in fiber (12 g/day), the amounts of fat and fiber were varied in the setting of a metabolic kitchen and carefully monitored meals. Forty‐eight women completed 58 protocols. When the diet was changed to low‐fat (20‐25% calories as fat) and high fiber (40 g/day), there were significant decreases in serum concentrations of estrone, estrone sulfate, testosterone, androstenedione, and sex hormone binding globulin (SHBG) and near significant decreases in estradiol and free estradiol. When independent effects were examined, high fiber alone caused a decrease in estradiol and SHBG, whereas fat and fiber caused the observed decrease in estrone sulfate. Dietary fat independently influenced the serum concentration of androstenedione. Increased dietary fiber caused a lengthening of the menstrual cycle by 0.72 day and a lengthening of the follicular phase by 0.85 day.

Tofu and soy drinks contain phytoestrogens

OBJECTIVE As the intakes of soy foods rise in the American diet, the weak estrogenic activity of plant phytoestrogens may reach biologically effective levels. We determined the content of phytoestrogens (plant compounds with weak estrogenic activity in human beings) in tofu, a commercially produced soy drink, and three soy-based formulas. DESIGN A modified isotope dilution gas chromatography-mass spectrometry method was used to analyze samples obtained from supermarkets or manufacturers. SAMPLES Two or three lots of duplicate samples of four brands of tofu, one commercially produced soy drink, and three soy-based specialty formulas were analyzed. Means and standard deviations were calculated for the isoflavones daidzein, Biochanin A, genistein, coumestrol, and formononetin. RESULTS Tofu soy products were highest in isoflavone content; means of brands ranged from 73.0 to 97.5 micrograms/g daidzein per g wet weight and 187.4 to 215.9 micrograms genistein per g wet weight. The commercial soy drink followed with 7.0 micrograms daidzein per g wet weight and 21.0 micrograms genistein per g wet weight; the soy-based formulas were nearly devoid of these two isoflavones. Mean levels of Biochanin A, formononetin, and coumestrol were very low or nil (eg, 0 to 1.0 microgram/g) in all products. CONCLUSIONS Tofu contained the highest amounts of isoflavones among the products tested, and there was some variability from brand to brand. The soy drink contained lesser amounts, and soy-based formulas were devoid of isoflavones.

Rice bran oil consumption and plasma lipid levels in moderately hypercholesterolemic humans.

The effect of rice bran oil, and oil not commonly consumed in the United States, on plasma lipid and apolipoprotein concentrations was studied within the context of a National Cholesterol Education Panel (NCEP) Step 2 diet and compared with the effects of canola, corn, and olive oils. The study subjects were 15 middle-aged and elderly subjects (8 postmenopausal women and 7 men; age range, 44 to 78 years) with elevated low-density lipoprotein (LDL) cholesterol (C) concentrations (range, 133 to 219 mg/dL). Diets enriched in each of the test oils were consumed by each subject for 32-day periods in a double-blind fashion and were ordered in a Latin square design. All food and drink were provided by the metabolic research unit. Diet components were identical (17% of calories as protein, 53% as carbohydrate, 30% as fat [< 7% as saturated fat], and 80 mg cholesterol/1000 kcal) except that two thirds of the fat in each diet was contributed by rice bran, canola, corn, or olive oil. Mean +/- SD plasma total cholesterol concentrations were 192 +/- 19, 194 +/- 20, 194 +/- 19, and 205 +/- 19 mg/dL, and LDL-C concentrations were 109 +/- 30, 109 +/- 26, 108 +/- 31, and 112 +/- 29 mg/dL after consumption of the rice bran, canola, corn, and olive oil-enriched diets, respectively. Plasma cholesterol and LDL-C concentrations were similar and statistically indistinguishable when the subjects consumed the rice bran, canola, and corn oil-enriched diets and lower than when they consumed the olive oil-enriched diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Communicating the Experience of Chronic Pain and Illness Through Blogging

Background Although more individuals are sharing their experiences with chronic pain or illness through blogging (writing an Internet web log), research on the psychosocial effects and motivating factors for initiating and maintaining a blog is lacking. Objective The objective was to examine via online questionnaire the perceived psychosocial and health benefits of blogging among patients who use this media to communicate their experience of chronic pain or illness. Methods A 34-item online questionnaire was created, tested, and promoted through online health/disease forums. The survey employed convenience sampling and was open from May 5 to July 2, 2011. Respondents provided information regarding demographics, health condition, initiation and upkeep of blogs, and dynamics of online communication. Qualitative data regarding respondents’ blogging experiences, expectations for blogging, and the perceived effects from blogging on the blogger’s health, interpersonal relationships, and quality of life were collected in the form of written narrative. Results Out of 372 respondents who started the survey, 230 completed the entire questionnaire. Demographic data showed survey respondents to be predominantly female (81.8%) and highly educated (97.2% > high school education and 39.6% with graduate school or professional degrees). A wide spectrum of chronic pain and illness diagnoses and comorbidities were represented. Respondents reported that initiating and maintaining an illness blog resulted in increased connection with others, decreased isolation, and provided an opportunity to tell their illness story. Blogging promoted accountability (to self and others) and created opportunities for making meaning and gaining insights from the experience of illness, which nurtured a sense of purpose and furthered their understanding of their illness. Conclusions Results suggest that blogging about chronic pain and illness may decrease a sense of isolation through the establishment of online connections with others and increases a sense of purpose to help others in similar situations. Further study involving a larger sample size, a wider range of education levels, and respondents with different types and magnitudes of illnesses will be needed to better elucidate the mechanism of the observed associations in this understudied area.

Increased carbohydrate consumption by rats as a function of 2-deoxy-D-glucose administration☆

Dietary self-selection was examined following the administration of the glucoprivic agent, 2-deoxy-D-glucose (2-DG), in adult male rats given access to separate sources of the three macronutrients, protein, fat and carbohydrate. All animals received injections (IP) of saline, 250, 500 and 750 mg/kg 2-DG with nutrient intakes measured at 2, 4, 6 and 24 hrs following injections. Animals consumed significantly more carbohydrate at 4, 6 and 24 hrs after injections of 500 and 750 mg/kg 2-DG than after saline injections. In contrast, fat intake was significantly suppressed by all three doses of 2-DG at 2 hr, by 250 and 750 mg/kg 2-DG at 4 and 6 hrs, and by 750 mg/kg 2-DG at 24 hr after injections. Protein intake was significantly decreased by all three doses of 2-DG at 2 hr after injections. As a result of the increase in carbohydrate intake and complimentary decrease in fat intake following 2-DG injections, total caloric intake of animals given the self-selection regime was not modified as a function of drug administration. In comparison, rats given a single nutritionally complete diet (ground Purina Laboratory Chow) consumed significantly more calories following 2-DG administration than following saline injections. The ability of animals to make appropriate modifications in nutrient selection following regulatory challenges is discussed.

A diet high in saturated fat and cholesterol accelerates simian immunodeficiency virus disease progression

Several lines of evidence suggest that dietary fat and cholesterol may play a role in the pathogenesis of human immunodeficiency virus (HIV) infection and disease progression. We examined the effect that an atherogenic diet (AD) high in saturated fatty acids and cholesterol has on disease progression and systemic inflammation in the simian immunodeficiency virus (SIV)-infected macaque model of acquired immunodeficiency syndrome. Macaques fed an AD had significantly more rapid disease progression, resulting in an increased risk of SIV-related death compared with that in control macaques (hazard ratio, 5.4 [95% confidence interval, 1.7-17.0]; P<.001). Peak viral load was higher in the AD group compared with control values, but further statistically significant differences were not detected at viral set point. The baseline plasma interleukin-18 level after 6 months of the AD was predictive of disease progression. Our findings may have important implications for HIV-infected individuals, because they suggest that dietary changes and manipulation of lipid metabolism could offer potential benefits by slowing disease progression.