109 research outputs found
The Effects on Toxicity of Circadian Patterning of Continuous Hepatic Artery Infusion
Long term continuous hepatic artery infusion of FUDR was carried out in 34 rats. In the animals who
received a constant infusion schedule of 15mg/kg/day all died of toxicity with a mean survival of 9.3 days.
If the pattern of the continuous infusion was changed so that over 60% of the infusion was given during
the hours of 3pm to 9pm then all of the animals survived the 14 day infusion. If the maximum dose of
infusion was changed so that 60% of the infusion was given at night from 3am to 9am the infusion
became more toxic and all the animals died in a mean of 5.5 days. Pathologic sectioning of all the livers
reflected the above outcomes with the greatest amount of hepatic necrosis in the animals on the night
cycles. This study underscores the recent advances in chronobiology demonstrating that for continuous
hepatic arterial infusions the timing of delivery is crucial in determining the toxicity
Cortisol patterns are associated with T cell activation in HIV.
ObjectiveThe level of T cell activation in untreated HIV disease is strongly and independently associated with risk of immunologic and clinical progression. The factors that influence the level of activation, however, are not fully defined. Since endogenous glucocorticoids are important in regulating inflammation, we sought to determine whether less optimal diurnal cortisol patterns are associated with greater T cell activation.MethodsWe studied 128 HIV-infected adults who were not on treatment and had a CD4(+) T cell count above 250 cells/µl. We assessed T cell activation by CD38 expression using flow cytometry, and diurnal cortisol was assessed with salivary measurements.ResultsLower waking cortisol levels correlated with greater T cell immune activation, measured by CD38 mean fluorescent intensity, on CD4(+) T cells (r = -0.26, p = 0.006). Participants with lower waking cortisol also showed a trend toward greater activation on CD8(+) T cells (r = -0.17, p = 0.08). A greater diurnal decline in cortisol, usually considered a healthy pattern, correlated with less CD4(+) (r = 0.24, p = 0.018) and CD8(+) (r = 0.24, p = 0.017) activation.ConclusionsThese data suggest that the hypothalamic-pituitary-adrenal (HPA) axis contributes to the regulation of T cell activation in HIV. This may represent an important pathway through which psychological states and the HPA axis influence progression of HIV
Mindfulness Intervention for Stress Eating to Reduce Cortisol and Abdominal Fat among Overweight and Obese Women: An Exploratory Randomized Controlled Study
Psychological distress and elevated cortisol secretion promote abdominal fat, a feature of the Metabolic Syndrome. Effects of stress reduction interventions on abdominal fat are unknown. Forty-seven overweight/obese women (mean BMI = 31.2) were randomly assigned to a 4-month intervention or waitlist group to explore effects of a mindfulness program for stress eating. We assessed mindfulness, psychological distress, eating behavior, weight, cortisol awakening response (CAR), and abdominal fat (by dual-energy X-ray absorptiometry) pre- and posttreatment. Treatment participants improved in mindfulness, anxiety, and external-based eating compared to control participants. Groups did not differ on average CAR, weight, or abdominal fat over time. However, obese treatment participants showed significant reductions in CAR and maintained body weight, while obese control participants had stable CAR and gained weight. Improvements in mindfulness, chronic stress, and CAR were associated with reductions in abdominal fat. This proof of concept study suggests that mindfulness training shows promise for improving eating patterns and the CAR, which may reduce abdominal fat over time
Effects of a mindfulness-based weight loss intervention in adults with obesity: A randomized clinical trial.
OBJECTIVE: To determine whether adding mindfulness-based eating and stress management practices to a diet-exercise program improves weight loss and metabolic syndrome components.
METHODS: In this study 194 adults with obesity were randomized to a 5.5-month program with or without mindfulness training and identical diet-exercise guidelines. Intention-to-treat analyses with multiple imputation were used for missing data. The primary outcome was 18-month weight change.
RESULTS: Estimated effects comparing the mindfulness to control arm favored the mindfulness arm in (a) weight loss at 12 months, -1.9 kg (95% CI: -4.5, 0.8; P = 0.17), and 18 months, -1.7 kg (95% CI: -4.7, 1.2; P = 0.24), though not statistically significant; (b) changes in fasting glucose at 12 months, -3.1 mg/dl (95% CI: -6.3, 0.1; P = 0.06), and 18 months, -4.1 mg/dl (95% CI: -7.3, -0.9; P = 0.01); and (c) changes in triglyceride/HDL ratio at 12 months, -0.57 (95% CI: -0.95, -0.18; P = 0.004), and 18 months, -0.36 (95% CI: -0.74, 0.03; P = 0.07). Estimates for other metabolic risk factors were not statistically significant, including waist circumference, blood pressure, and C-reactive protein.
CONCLUSIONS: Mindfulness enhancements to a diet-exercise program did not show substantial weight loss benefit but may promote long-term improvement in some aspects of metabolic health in obesity that requires further study
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Adipose Concentrations of Organochlorine Compounds and Breast Cancer Recurrence in Long Island, New York
Several studies have measured the association between blood or adipose concentrations of organochlorinated compounds (OCs), such as pesticides and polychlorinated biphenyls (PCBs), and breast cancer. The estrogenic effects of OCs might adversely affect breast cancer recurrence. The participants were 224 women with nonmetastatic breast cancer enrolled in a New York-based case-control study. Supercritical fluid extraction followed by gas chromatography was conducted on adipose surgical specimens to determine OC concentrations. The mean follow-up time from surgery was 3.6 years. Thirty women (13.4%) were diagnosed with a recurrence. The concentration of pesticides and PCBs was correlated with baseline age and body mass index, but not with cancer stage. The highest tertile of total PCB concentration was associated with an increased risk of recurrence [relative risk (RR), 2.9; 95% confidence interval (CI), 1.02-8.2 versus the lowest tertile]. The risk for the highest tertile of the PCB congener Ballschmiter and Zell 118 was 4.0 (95% CI, 1.3-4.9). There was an increased risk for the middle level of the most abundant pesticide, 1,1-dichloro-2,2-di(4-chlorophenyl)ethylene (RR, 2.3; 95% CI, 0.9-5.7), and for beta-hexachlorocyclohexane, but not for their highest levels. Self-reported home termiticide exposure, alcohol consumption (> or = 1 drink/day), and race were not associated with prognosis. The RR for current cigarette smoking at diagnosis was 2.1 (95% CI, 0.9-5.1). In contrast to previous data showing no relationship between OC exposure and risk of breast cancer in these women, adipose PCB concentrations were associated with tumor recurrence. Pesticide levels were not related to recurrence
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Breast cancer risk in relation to adipose concentrations of organochlorine pesticides and polychlorinated biphenyls in Long Island, New York
To assess a possible etiological role of organochlorine compounds in breast cancer development on Long Island, a high-risk region of New York State, concentrations of organochlorine pesticides and polychlorinated biphenyls (PCBs) were measured in the adipose tissue of 232 women with breast cancer and 323 hospital controls admitted to surgery for benign breast disease or non-breast-related conditions. Seven pesticide residues and 14 PCB congeners were assayed via a supercritical fluid extraction method followed by gas chromatography with electron capture detection. After adjustment for age and body mass index, which were strongly correlated with organochlorine levels, adipose concentrations of 1,1- dichloro-2,2-di(4-chlorophenyl)ethylene, total pesticides, and total polychlorinated biphenyls (PCBs) did not differ significantly between cases and controls. The relative abundance of individual pesticide species and PCB congeners was similar in cases and controls. Odds ratios adjusted for age, BMI, hospital, and race gave no evidence of a dose-response for 1,1-dichloro-2,2-di(4- chlorophenyl)ethylene, total pesticides, or total PCBs, whether stratified by estrogen receptor status or not. Breast cancer risk among Long Island residents was not elevated compared with residents of the adjacent New York City borough of Queens. We did not confirm a previously reported association between breast cancer risk and levels of PCB congener 118 (2,3',4,4',5- pentachlorobiphenyl), nor did we observe an association with the most abundant congener 153 (2,2',4,4',5,5'- hexachlorobiphenyl), a strong inducer of phase I enzymes that was reported recently to have estrogenic properties. Only PCB congener 183 (2,2',3,4,4',5',6- heptachlorobiphenyl), which is also an inducer, was significantly associated with risk, with an adjusted odds ratio of 2.0 (95% confidence interval, 1.2–3.4) in women with adipose levels >5.67 ng/g; the biological importance of this observation is unclear without confirmation in additional studies. Although neither the present nor other studies have provided convincing evidence of an association between body burden of 1,1,1-trichloro-2,2- bis(4-chlorophenyl)ethane and PCBs with cancer of the breast, these compounds are rated as “possible” and “probable” human carcinogens, respectively, by the International Agency for Research on Cancer. Investigations of associations with cancer at other sites should be carried out
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Relative abundance of organochlorine pesticides and polychlorinated biphenyls in adipose tissue and serum of women
Some organochlorine pesticides (OCPs) and PCBs are under investigation as possible risk factors for breast cancer because of their estrogenic properties and widespread presence in the environment. It is important to know whether adipose tissue used by some investigators and serum assays used by others can provide comparable information on body burden. Concentrations of seven OCPs or their breakdown products as well as 14 PCB congeners were measured in the adipose tissue and serum of 293 women enrolled as controls in a case-control study of environmental factors for breast cancer in Long Island, New York, a high-risk region. Adipose OCP/PCB levels were measured using a supercritical fluid extraction method developed by the authors. 1,1-Dichloro-2,2-di(4-chlorophenyl)ethylene (p,p’- DDE) was detected in all adipose and serum samples; two chlordane derivatives, β-hexachlorocyclohexane (a lindane isomer) and hexachlorobenzene, were detected in at least 92% of adipose samples. The di-ortho hexachlorinated PCB congeners 2,4,5,2’,4’,5’- hexachlorobiphenyl and 2,3,4,2’,4’,5’-hexachlorobiphenyl were detected in all adipose and over 98% of serum samples. 1,1-Dichloro-2,2-di(4-chlorophenyl)ethylene comprised 77% of total pesticide residues in adipose and 71% in serum. 2,4,5,2’,4’,5’-Hexachlorobiphenyl comprised 24% of adipose and 21 % of serum PCBs. The relative concentration patterns of the 14 PCB congeners were similar to those reported in other human studies and were also typical of patterns reported in environmental samples from various biota, including mammals and birds, but differed substantially from patterns reported in occupationally exposed workers. All adipose-serum correlations for pesticides and most PCBs were statistically significant. Either serum or adipose OCP/PCB levels of a variety of environmental organochlorine compounds may serve as useful biomarkers of body burden
Associations of weight stigma with cortisol and oxidative stress independent of adiposity.
OBJECTIVE: Weight discrimination is associated with increased risk of obesity. The mechanism of this relationship is unknown, but being overweight is a highly stigmatized condition and may be a source of chronic stress that contributes to the development and pathophysiology of obesity. The objective of this study was to test whether weight stigma is associated with physiological risk factors linked to stress and obesity, including hypercortisolism and oxidative stress, independent of adiposity. METHOD: We examined the frequency of experiencing situations involving weight stigma and consciousness of weight stigma in relation to hypothalamic–pituitary–adrenal axis activity and oxidative stress (F(2)-isoprostanes) in 45 healthy overweight to obese women. RESULTS: Independent of abdominal fat, weight stigma was significantly related to measures of cortisol (including salivary measures of cortisol awakening response and serum morning levels) as well as higher levels of oxidative stress. Perceived stress mediated the relationship between weight stigma consciousness and the cortisol awakening response. CONCLUSION: These preliminary findings show that weight stigma is associated with greater biochemical stress, independent of level of adiposity. It is possible that weight stigma may contribute to poor health underlying some forms of obesity
Apalutamide Treatment and Metastasis-free Survival in Prostate Cancer
Background Apalutamide, a competitive inhibitor of the androgen receptor, is under development for the treatment of prostate cancer. We evaluated the efficacy of apalutamide in men with nonmetastatic castration-resistant prostate cancer who were at high risk for the development of metastasis. Methods We conducted a double-blind, placebo-controlled, phase 3 trial involving men with nonmetastatic castration-resistant prostate cancer and a prostate-specific antigen doubling time of 10 months or less. Patients were randomly assigned, in a 2:1 ratio, to receive apalutamide (240 mg per day) or placebo. All the patients continued to receive androgen-deprivation therapy. The primary end point was metastasis-free survival, which was defined as the time from randomization to the first detection of distant metastasis on imaging or death. Results A total of 1207 men underwent randomization (806 to the apalutamide group and 401 to the placebo group). In the planned primary analysis, which was performed after 378 events had occurred, median metastasis-free survival was 40.5 months in the apalutamide group as compared with 16.2 months in the placebo group (hazard ratio for metastasis or death, 0.28; 95% confidence interval [CI], 0.23 to 0.35;
Environmental toxins and breast cancer on Long Island. I. Polycyclic aromatic hydrocarbon DNA adducts
Polycyclic aromatic hydrocarbons (PAH) are potent mammary carcinogens in rodents, but their effect on breast cancer development in women is not clear. To examine whether currently measurable PAH damage to DNA increases breast cancer risk, a population-based case-control study was undertaken on Long Island, NY. Cases were women newly diagnosed with in situ and invasive breast cancer; controls were randomly selected women frequency matched to the age distribution of cases. Blood samples were donated by 1102 (73.0%) and 1141 (73.3%) of case and control respondents, respectively. Samples from 576 cases and 427 controls were assayed for PAH-DNA adducts using an ELISA. The geometric mean (and geometric SD) of the log-transformed levels of PAH-DNA adducts on a natural scale was slightly, but nonsignificantly, higher among cases [7.36 (7.29)] than among controls [6.21 (4.17); p = 0.51]. The age-adjusted odds ratio (OR) for breast cancer in relation to the highest quintile of adduct levels compared with the lowest was 1.51 [95% confidence interval (CI), 1.04 –2.20], with little or no evidence of substantial confounding (corresponding multivariate-adjusted OR, 1.49; 95% CI, 1.00 –2.21). There was no consistent elevation in risk with increasing adduct levels, nor was there a consistent association between adduct levels and two of the main sources of PAH, active or passive cigarette smoking or consumption of grilled and smoked foods. These data indicate that PAH-DNA adduct formation may influence breast cancer development, although the association does not appear to be dose dependent and may have a threshold effect
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