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Biomedical subjects

Kenneth Jones

Publications and source records attributed to Kenneth Jones.

18 recordsLinked to original sources
PubMed2006

Reliability and validity of an assessment of usual phytoestrogen consumption (United States).

OBJECTIVE: To evaluate the reliability and validity of a food-frequency questionnaire (FFQ) and database designed to quantify phytoestrogen consumption. METHODS: This study included 195 members of the California Teachers Study (CTS) cohort who, over a 10-month period, completed four 24-h dietary recalls, a pre- and post-study FFQ, and provided two 24-h urine specimens. Participants (n = 106) in a parallel study (and 18 women who dropped out of the long-term study) completed a single recall and FFQ, and provided one 24-h urine specimen. Urinary phytoestrogens were determined using liquid chromatography-mass spectrometry. Reliability and validity were evaluated using Shrout-Fleiss intraclass correlations and energy-adjusted deattenuated Pearson correlations, respectively. RESULTS: Correlations reflecting the reproducibility of the FFQ phytoestrogen assessment ranged from 0.67 to 0.81. Validity correlations (FFQ compared to dietary recalls) ranged from 0.67 to 0.79 for the major phytoestrogenic compounds (i.e., daidzein, genistein, and secoisolariciresinol) and 0.43 to 0.54 for the less common compounds. Compared to urinary levels, validity correlations ranged from 0.41 to 0.55 for the isoflavones and 0.16 to 0.21 for total lignans. CONCLUSION: Our isoflavone assessment is reproducible, valid, and an excellent tool for evaluating the relationship with disease risk in non-Asian populations. Further research is needed before these tools can accurately be used to assess lignan consumption.

Adult↗
PubMed2005

Contrasting effects of puerarin and daidzin on glucose homeostasis in mice.

Puerarin and daidzin are the major isoflavone glucosides found in kudzu dietary supplements. In this study, we demonstrated that puerarin significantly improves glucose tolerance in C57BL/6J-ob/ob mice, an animal model of type 2 diabetes mellitus, blunting the rise in blood glucose levels after i.p. administration of glucose. In contrast, daidzin, the O-glucoside, had a significant but opposite effect, impairing glucose tolerance as compared to saline-treated controls. When they were administered i.p. with (14)C-glucose to C57BL/6J lean mice, puerarin inhibited glucose uptake into tissues and incorporation into glycogen, while daidzin stimulated glucose uptake, showing an opposite effect to puerarin. Puerarin also antagonized the stimulatory effect of decyl-beta-D-thiomaltoside, an artificial primer of glycogen synthesis, which increases (14)C-glucose uptake and incorporation into glycogen in mouse liver and heart. A liquid chromatography-tandem mass spectrometry procedure was used to investigate the metabolism and bioavailability of puerarin and daidzin. The blood puerarin concentration-time curve by i.p. and oral administration indicated that puerarin was four times more bioavailable via i.p. injection than via the oral route of administration. This may account for the increased hypoglycemic effect seen in the i.p. glucose tolerance test vs that seen orally. Our results suggest that puerarin is rapidly absorbed from the intestine without metabolism, while daidzin is hydrolyzed to the aglycone daidzein. The opposing effects of puerarin and daidzin on glucose homeostasis may have implications for the activity of dietary supplements that contain both of these isoflavonoids.

Animals↗
PubMed2005

Long-term dietary habits affect soy isoflavone metabolism and accumulation in prostatic fluid in caucasian men.

The soy isoflavones daidzein and genistein are believed to reduce prostate cancer risk in soy consumers. However, daidzein can be metabolized by the intestinal flora to form a variety of compounds with different bioactivities. In the current study, we investigated the influence of long-term dietary habits on daidzein metabolism in healthy Caucasian men (19-65 y old). A secondary goal was to compare plasma and prostatic fluid concentrations of 5 isoflavonoids: genistein, daidzein, equol, dihydrodaidzein, and O-desmethylangolensin. Baseline plasma levels of isoflavonoids were quantitated in 45 men by HPLC-electrospray ionization-MS. Participants then consumed a soy beverage daily for 1 wk, and post-soy isoflavonoid levels were quantitated in plasma and prostatic fluid. Equol was the only metabolite that appeared to be influenced by routine dietary habits. Stratified analyses revealed that men who had consumed > or =30 mg soy isoflavones/d for at least 2 y had 5.3-times the probability of producing equol than men who had consumed < or =5 mg/d (P = 0.014). Additionally, those men who consumed animal meat regularly had 4.7-times the probability of producing equol than men who did not consume meat (P = 0.023). Equol production was not linked to age, BMI, or the consumption of yogurt, dairy, fruit, or American-style fast food. Daidzein and its metabolites (but not genistein) were typically present at higher levels in prostate fluid than plasma (median = 4-13 times that in plasma). In conclusion, our data suggest that the ability of Caucasian men to produce equol is favorably influenced by the long-term consumption of high amounts of soy and the consumption of meat. Last, the high concentrations of isoflavonoids in prostatic fluid increases the potential for these compounds to have direct effects in the prostate.

Adult↗
PubMed2004

Identification of puerarin and its metabolites in rats by liquid chromatography-tandem mass spectrometry.

Puerarin (daidzein-8-C-glucoside) is the major bioactive isoflavone of kudzu root (the root of Pueraria lobata). Its metabolic fate, however, is not well-known. In this study, a sensitive and specific LC-ESI-MS/MS method for the determination of puerarin and its metabolites daidzein, dihydrodaidzein, and equol was developed for their analysis in biological samples. Two new metabolites of puerarin, mono- and dihydroxylated derivatives, were detected in the urine and feces of rats after oral administration. The persistence of puerarin in blood and urine as the principal metabolic form for the period of 4-72 h after oral administration suggested that puerarin is rapidly absorbed from the intestine without metabolism. Its presence in organs such as the brain suggests that this glucoside may enter tissues by specific transport pathways. Study of these metabolites may provide further understanding of the health beneficial effects of puerarin in kudzu dietary supplements.

Animals↗
PubMed2004

Inulin effects on bioavailability of soy isoflavones and their calcium absorption enhancing ability.

The effect of inulin on isoflavone absorption and the effect of isoflavones and synergy with inulin on calcium absorption in rats was investigated. Rats (n = 48) were divided into three groups and fed inulin (50 mg/g), isoflavone (8 mg/g) or inulin + isoflavone (50 mg/g + 8 mg/g) diets for 21 days. After a 2-h fast, rats were given (45)Ca orally or intraperitoneally, together with 25 mg of calcium as calcium acetate. Blood and femurs were collected 4 days later. Sera were analyzed for isoflavones using HPLC-MS, femurs for (45)Ca by beta-scintillation counting, and total femoral calcium by atomic absorption spectroscopy. Both groups fed isoflavones had similar and significantly higher weight-adjusted total femoral calcium content compared to the inulin-fed group (p < 0.0001). (45)Ca absorption was significantly higher (p < 0.01) when isoflavones were added to the diet, and serum equol was significantly lower (p < 0.01) when inulin was added to the diet containing isoflavones. We conclude that isoflavones enhance calcium absorption, without synergy from inulin, and that inulin decreases equol production.

Absorption↗
PubMed2004

Structural modeling of dynamic changes in memory and brain structure using longitudinal data from the normative aging study.

This is an application of new longitudinal structural equation modeling techniques to time-dependent associations of memory and brain structure measurements. There were 225 participants aged 30-80 years at baseline who were measured again after a 7-year interval on both the lateral ventricular size and Wechsler memory score. Multiple regression analyses show nonlinear associations with age but no relationships among longitudinal changes. Mixed-effects latent growth curve analyses and analyses based on latent difference scores indicate that longitudinal changes in both variables are reasonably well described by an exponential or dual change model. Bivariate dynamic structural equation modeling analyses indicate age-lagged changes operate in a coupled-over-time fashion, with the brain measure (lateral ventricular size) as a leading indicator in time of memory (Wechsler memory score) declines.

Adult↗
PubMed2003

Profiling and quantification of isoflavonoids in kudzu dietary supplements by high-performance liquid chromatography and electrospray ionization tandem mass spectrometry.

The kudzu vine (Pueraria sp.) is a rich source of isoflavones. Dietary supplements based on kudzu have become commercially available. In the present study, liquid chromatography coupled with negative and positive electrospray ionization tandem mass spectrometry (MS/MS) and diode array detection (DAD) has been used for the detection and characterization of isoflavonoids in kudzu dietary supplements (KDS). The MS/MS spectrum of the protonated ion of puerarin showed characteristic product ions of the C-glycoside unit itself, whereas daidzin generated an abundant Y(0)(+) aglycon ion in its product ion spectrum. A base peak due to the loss of 120 Da [M + H - 120](+) is the diagnostic ion for C-glycosides. Neutral loss scans allowed for the detection of other C- and O-glycosides in the methanolic extract of KDS, and their structures have been proposed. The concentration of isoflavonoids in the methanolic extract of commercially available KDS was quantified by using DAD-HPLC. Puerarin, rather than daidzin, was the most abundant component (8.44-30.60 mg/capsule) in commercially available KDS.

Chromatography, High Pressure Liquid↗
PubMed2003

Review of sangre de drago (Croton lechleri)--a South American tree sap in the treatment of diarrhea, inflammation, insect bites, viral infections, and wounds: traditional uses to clinical research.

OBJECTIVE: The objective of this review is to provide an overview of the pharmacologic evidence that may or may not support clinical and ethnomedical uses of the sap of sangre de drago (dragon's blood; Croton lechleri Müll. Arg.). Data sources used were BIOSIS, EMBASE, PubMed, TOXLIT, International Pharmaceutical Abstracts, manual searches, papers on file from peer-reviewed journals, textbooks available at Armana Research, Inc., and researchers in the field of South American botanical medicine. CONCLUSIONS: The results of in vitro and in vivo studies largely support the majority of ethnomedical uses of sangre de drago including the treatment of diarrhea, wounds, tumors, stomach ulcers, herpes infection, the itching, pain and swelling of insect bites, and other conditions. Clinical studies of sangre de drago products have reported positive results in the treatment of traveler's and watery diarrhea and the symptoms of insect bites. Because the sap has shown low toxicity and preparations used in clinical studies were well tolerated, further clinical and pharmacologic studies are anticipated. Acknowledgment of the diversity in the chemical makeup of the sap from one geographic area to another and the recent characterization of alkaloid chemotypes of sangre de drago will require that materials developed for clinical use are standardized.

Animals↗
PubMedDate not supplied

Prevalence and patterns of anxiety and depression in patients undergoing elective percutaneous transluminal coronary angioplasty.

BACKGROUND: The use of elective percutaneous transluminal coronary angioplasty (PTCA) as a treatment for coronary heart disease is increasing. Despite this, little is known about the prevalence and patterns of anxiety and depression experienced by patients undergoing and recovering from this procedure. Anxiety and depression are factors known to negatively influence recovery after a cardiac event. OBJECTIVE: The purpose of this study was to (1) describe the levels of anxiety and depression reported by patients pre- and postelective PTCA, and (2) determine associations evident between anxiety and depression and the sociodemographic and clinical variables of gender, marital status, history of acute myocardial infarction, and attendance at cardiac rehabilitation. METHODS: In this descriptive, repeated-measures investigation, patients (n = 140) were requested to complete the Spielberger State Trait Anxiety Inventory and Cardiac Depression Scale (CDS) at three time points: 0(1) before admission for elective PTCA (T(1)); (2) 6 to 8 weeks (T(2)) after PTCA; and (3) 6 to 8 months (T(3)) after PTCA. RESULTS: A typical participant was male (75%), of European ethnicity (90%), aged 62 years (standard deviation = 10.7) with single or double vessel disease, and had attended cardiac rehabilitation in the past. At T(1), 16% of men and 24% of women had state anxiety scores comparable to those experienced by neuropsychiatric patients. Trait anxiety scores remained relatively constant over time; higher scores at T(1) were associated with past acute myocardial infarction. CDS scores at T(2) and T(3) were significantly lower than those at T(1). However, an unexpected increase in CDS scores occurred at T(3), compared with T(2). At T(3), 14% of men and 10% of women were depressed, relative to T(1). CONCLUSION: The findings lend support for the closer surveillance of emotional status in this population. Specialist nurses have the potential to play a greater role in identifying those at risk of developing anxiety and depression. However, this unmet need will remain unmet until specialist nurses who spend the most face-to-face time with patients are equipped with the skills and resources to systematically identify those "at risk."

Adult↗
PubMedDate not supplied

Changes in patients' illness representations before and after elective percutaneous transluminal coronary angioplasty.

BACKGROUND: Elective percutaneous transluminal coronary angioplasty (PTCA) is an increasingly popular treatment for coronary heart disease, but little is known about individuals' cognitive responses to this intervention. As part of adapting to living with chronic disease, individuals develop unique models, or illness representations, which enable them to "make sense" of their predicament. Inaccurate illness representations have a negative affect on patient behaviors and outcomes. OBJECTIVE: This purpose of this study was to examine changes in patients' self-reported illness representations before and after first-time elective PTCA. METHODS: In this descriptive, repeated-measures design, illness representations were evaluated in 117 consecutive patients attending a pre-PTCA clinic using the Illness Perceptions Questionnaire. Data were collected pre- and 6 to 8 months post-elective PTCA. RESULTS: A typical participant was male (75%), of European ethnicity (90%), and aged 62 years (+/-10.7). Six to 8 months post-PTCA self-reported symptom frequency (Z = 8.034, N-ties, P = .000) and duration decreased significantly (Z = 8.361, N-ties 20, P = .000) compared with pre-PTCA levels. Timeline scores increased significantly (Z = 3.46, N-ties 10, P = .001) indicating a shift in patients' representations of their disease from an acute to a chronic model. Cure/control and consequence scores decreased significantly, indicating that representations regarding personal control over their illness weakened (Z = 3.251, N-ties 18, P = .001), as did their representation of their illness as having serious consequences (Z = 5.250, N-ties 0, P = .00). CONCLUSION: Some inaccuracies in illness representations were evident, some of which evolved to more realistic representations, whereas others did not. In the era of promoting effective self-management among those living with chronic diseases a clear understanding of illness representation in the context of coronary heart disease is valuable, particularly as inaccuracies are associated with negative outcomes.

Aged↗
PubMedDate not supplied

Heart disease attributions of patients prior to elective percutaneous transluminal coronary angioplasty.

One hundred forty consecutive subjects attending a clinic prior to undergoing elective percutaneous transluminal coronary angioplasty were asked about what they believed had caused their coronary heart disease (CHD). The aim was to determine gender differences in responses and compare patients' perceived causal attributions for CHD with their own coronary risk factor profile documented by their attending physician. Female subjects most commonly cited stress as the cause of their CHD, followed by family history, cholesterol, and cigarette smoking. Males showed a different pattern of attribution, with poor diet being the most frequently cited factor, followed by cigarette smoking, stress, and family history. A significantly greater proportion of males than females attributed their illness to behavioral causes rather than to biological causes. A positive history for the coronary risk factors cholesterol (84%), family history (43%), and hypertension (55%), as documented by attending physician, was discordant with causal attributions expressed by patients which were 17%, 31%, and 4% respectively. These findings demonstrate the need to improve communication and find a common "platform" of understanding between patient and practitioner when discussing coronary risk factors in order to establish a collaborative action plan for successful and long-term lifestyle change.

Angioplasty, Balloon, Coronary↗
PubMedDate not supplied

Public health response to bioterrorism with Bacillus anthracis: coordinating public health laboratory, communication, and law enforcement.

In October 2001, public health departments across the United States were part of an intensive response to a bioterrorism event using anthrax spores delivered by mail. It is useful to examine this experience as an unscripted exercise of bioterrorism response capacity, more realistic than scenarios of planned exercises. The event particularly challenged public health laboratory and communications capacity, but it also tested surveillance and training capacity. The bioterrorism response demonstrated the importance of strong partnerships between the public health laboratory and emergency response agencies as well as medical providers and the usefulness of open, flexible communication strategies.

Anthrax↗
PubMedDate not supplied

Astragalus.

Explore the source record for details and available documents.

Astragalus Plant↗
PubMedDate not supplied

The promise of special health courts for Louisiana.

Louisiana's medical justice system is failing for both providers and patients. Decisions made in the system are too often inaccurate, uninformed, and unpredictable, and the compensation process is slow and inefficient. Moreover, the nature of the current system deters system improvements in patient safety and the quality of care. Comprehensive reform is needed and a new initiative that would create special "health courts" to resolve medical malpractice cases may be the best solution.

Compensation and Redress↗