640 research outputs found
Comparison of Subjective Responses to Oral and Intravenous Alcohol Administration under Similar Systemic Exposures
Objective
To test whether an individual's subjective responses to alcohol are similar when the breath alcohol concentration (BrAC) trajectory resulting from oral administration is matched by intravenous administration.
Background
Individuals perceive the effects of alcohol differently, and the variation is commonly used in research assessing the risk for developing an alcohol use disorder. Such research is supported by both oral and intravenous alcohol administration techniques, and any differences attributable to the route employed should be understood.
Methods
We conducted a 2âsession, withinâsubject study in 44 young adult, healthy, nonâdependent drinkers (22 females and 22 males). In the first session, subjects ingested a dose of alcohol which was individually calculated, on the basis of total body water, to yield a peak BrAC near 80 mg/dl, and the resulting BrAC trajectory was recorded. A few days later, subjects received an intravenous alcohol infusion rate profile, preâcomputed to replicate each individual's oral alcohol BrAC trajectory. In both sessions, we assessed 4 subjective responses to alcohol: SEDATION, SIMULATION, INTOXICATION, and HIGH; at baseline and frequently for 4 hours. We compared the individualsâ baselineâcorrected responses at peak BrAC and at halfâpeak BrAC on both the ascending and descending limbs. We also computed and compared Pearsonâproduct moment correlations of responses by route of administration, the Mellanby measure of acute adaptation to alcohol, and the area under the entire response curve for each subjective response.
Results
No significant differences in any measure could be attributed to the route of alcohol administration. Eleven of 12 response comparisons were significantly correlated across the routes of alcohol administration, with 9 surviving correction for multiple measures, as did the Mellanby effect and area under the response curve correlations.
Conclusion
The route of alcohol administration has a minimal effect on subjective responses to alcohol when an individual's BrAC exposure profiles are similar
Classifying the embedded young stellar population in Perseus and Taurus & the LOMASS database
Context. The classification of young stellar objects (YSOs) is typically done
using the infrared spectral slope or bolometric temperature, but either can
result in contamination of samples. More accurate methods to determine the
evolutionary stage of YSOs will improve the reliability of statistics for the
embedded YSO population and provide more robust stage lifetimes. Aims. We aim
to separate the truly embedded YSOs from more evolved sources. Methods. Maps of
HCO+ J=4-3 and C18O J=3-2 were observed with HARP on the James Clerk Maxwell
Telescope (JCMT) for a sample of 56 candidate YSOs in Perseus and Taurus in
order to characterize emission from high (column) density gas. These are
supplemented with archival dust continuum maps observed with SCUBA on the JCMT
and Herschel PACS to compare the morphology of the gas and dust in the
protostellar envelopes. The spatial concentration of HCO+ J=4-3 and 850 micron
dust emission are used to classify the embedded nature of YSOs. Results.
Approximately 30% of Class 0+I sources in Perseus and Taurus are not Stage I,
but are likely to be more evolved Stage II pre-main sequence (PMS) stars with
disks. An additional 16% are confused sources with an uncertain evolutionary
stage. Conclusions. Separating classifications by cloud reveals that a high
percentage of the Class 0+I sources in the Perseus star forming region are
truly embedded Stage I sources (71%), while the Taurus cloud hosts a majority
of evolved PMS stars with disks (68%). The concentration factor method is
useful to correct misidentified embedded YSOs, yielding higher accuracy for YSO
population statistics and Stage timescales. Current estimates (0.54 Myr) may
overpredict the Stage I lifetime on the order of 30%, resulting in timescales
of 0.38 Myr for the embedded phase.Comment: 33 pages, 21 figures, 6 tables, Accepted to be published in A&
Effects of 12-O-tetradecanoylphorbol-13-acetate on the incorporation of labelled precursors into RNA, DNA and protein in epidermis, dermis and subcutis from precancerous mouse skin with reference to enhanced tumorigenesis
The effects of a single application of 1.8 nmol 12-O-tetra-decanoylphorbol-13-acetate (TPA) on precursor incorporation into RNA, DNA and protein in the epidermis, dermis and subcutis from 3-methylcholanthrene (MCA) injected precancerous mouse skin were studied at various time points between 3 and 96 h. In the precancerous tissues, the rates of incorporation of [3H]uridine into RNA did not alter appreciably from those in the control tissues; while the rates of [3H]methylthymidine incorporation into DNA were elevated with peaks appearing between 6 and 12 h, at 24 h and at 72 h in epidermis, dermis and subcutis. The rate of incorporation of [14C] leucine into protein was markedly elevated in all the three tissues which showed 3-4 sharp peaks. The maximum stimulation ranged between 14 and 20 times that of the control. A single application of TPA to the precancerous mouse skin induced early stimulation of precursor incorporation into all the three macromolecules in epidermis, dermis and subcutis. The increased stimulation was maintained for 36- 72 h. The patterns of incorporation of [3H]methylthymidine into DNA gave rise to 2-3 peaks of elevated uptake in each tissue up to 36-48 h. A lowered rate of DNA synthesis between 48 and 60 h was followed by a peak at 72 h. In each group, epidermal mitotic activity correlated well with spurts of precursor incorporation into cellular DNA. The observations indicate that TPA recruits more cells into the DNA synthetic phase and accelerates selective growth of preneoplastic cells during tumor progression
Maternal self-reported prenatal depressive symptoms predict infant NR3C1 1F and BDNF IV DNA methylation.
Prenatal maternal psychological distress increases risk for adverse infant outcomes.
However, the biological mechanisms underlying this association remain unclear.
Prenatal stress can impact fetal epigenetic regulation that could underlie changes in
infant stress responses. It has been suggested that maternal glucocorticoids may
mediate this epigenetic effect. We examined this hypothesis by determining the
impact of maternal cortisol and depressive symptoms during pregnancy on infant
NR3C1 and BDNF DNA methylation. Fifty-seven pregnant women were recruited
during the second or third trimester.
Participants self-reported depressive symptoms
and salivary cortisol samples were collected diurnally and in response to a stressor.
Buccal swabs for DNA extraction and DNA methylation analysis were collected from
each infant at two months of age, and mothers were assessed for postnatal depressive
symptoms. Prenatal depressive symptoms significantly predicted increased NR3C1 1F
DNA methylation in male infants ( 2.147 = Űł , P = 0.044). Prenatal depressive
symptoms also significantly predicted decreased BDNF IV DNA methylation in both
male and female infants ( -3.244 = Űł , P = 0.013). No measure of maternal cortisol
during pregnancy predicted infant NR3C1 1F or BDNF promoter IV DNA
methylation. Our findings highlight the susceptibility of males to changes in NR3C1
DNA methylation and present novel evidence for altered BDNF IV DNA methylation
in response to maternal depression during pregnancy. The lack of association between
maternal cortisol and infant DNA methylation suggests that effects of maternal
depression may not be mediated directly by glucocorticoids. Future studies should
consider other potential mediating mechanisms in the link between maternal mood
and infant outcome
Evaluation of carcinogenic/co-carcinogenic activity of a common chewing product, pan masala, in mouse skin, stomach and esophagus
Pan masala, a dry powdered mixture of areca nut, catechu, lime, unspecified spices and flavoring agents, has gained widespread popularity as a chewing substitute in India. In this study, the carcinogenic and tumor-promoting potential of an ethanolic pan masala extract (EPME) was determined using skin of S/RVCri-ba mice and forestomach and esophagus of ICRC mice as the target tissues. Carcinogenic activity of pan masala was tested by painting the mouse skin for 40 weeks with EPME or by gavage feeding for 6 months. Following initiation with 9,10-dimethylbenz(a)anthracene (DMBA), carcinogenesis of mouse skin was promoted with different doses of EPME, while gastric- and esophageal-tumor-promoting activity was determined by administering EPME by gavage to animals initiated with diethylnitrosamine (DEN). The ability of EPME to effect progression of skin papilloma to carcinoma and cutaneous alterations after a single or multiple EPME treatment were also evaluated. EPME at 25 mg per dose promoted skin-papilloma formation between 30 and 40 weeks of treatment and enhanced the rate of conversion of papilloma to carcinoma. Induction of mild epidermal hyperplasia, dermal edema, increase in epidermal mitotic activity and the rate of epidermal and dermal DNA synthesis by EPME correlated well with its skin-tumor-promoting potential. In ICRC mice, EPME was inactive as a complete carcinogen, but effectively promoted the development of forestomach and esophageal papilloma and carcinoma in a concentration-dependent manner. The tumor incidence at 25 mg EPME per dose was comparable with that obtained in the 12-0-tetradecanoylphorbol-13 acetate(TPA)-treated group. The findings indicate that habitual pan-masala use may exert carcinogenic and co-carcinogenic influence
The acute psychobiological impact of the intensive care experience on relatives.
There is a growing awareness amongst critical care practitioners that the impact of intensive care medicine extends beyond the patient to include the psychological impact on close family members. Several studies have addressed the needs of relatives within the intensive care context but the psychobiological impact of the experience has largely been ignored. Such impact is important in respect to health and well-being of the relative, with potential to influence patient recovery. The current feasibility study aimed to examine the acute psychobiological impact of the intensive care experience on relatives. Using a mixed methods approach, quantitative and qualitative data were collected simultaneously. Six relatives of patients admitted to the intensive care unit (ICU) of a District General Hospital, were assessed within 48 h of admission. Qualitative data were provided from semi-structured interviews analysed using interpretative phenomenological analysis. Quantitative data were collected using a range of standardised self-report questionnaires measuring coping responses, emotion, trauma symptoms and social support, and through sampling of diurnal salivary cortisol as a biomarker of stress. Four themes were identified from interview: the ICU environment, emotional responses, family relationships and support. Questionnaires identified high levels of anxiety, depression and trauma symptoms; the most commonly utilised coping techniques were acceptance, seeking support through advice and information, and substance use. Social support emerged as a key factor with focused inner circle support relating to family and ICU staff. Depressed mood and avoidance were linked to greater mean cortisol levels across the day. Greater social network and coping via self-distraction were related to lower evening cortisol, indicating them as protective factors in the ICU context. The experience of ICU has a psychological and physiological impact on relatives, suggesting the importance of identifying cost-effective interventions with evaluations of health benefits to both relatives and patients
Are female children more vulnerable to the long-term effects of maternal depression during pregnancy?
BACKGROUND: Female fetuses are more vulnerable to high levels of maternal glucocorticoids. We examined whether exposure to prenatal maternal depression, a condition associated with high glucocorticoids, carries greater risk for depression at 12 and 18 years in girls. METHODS: Our sample comprised 7959 mothers and children from the Avon Longitudinal Study of Parents and Children following imputation for missing data. Maternal depression was assessed pre-and post-natally, and offspring depression at ages 12 and 18. We used logistic regression models to examine the relationship between exposure to prenatal and postnatal depression and offspring depression at 18 and 12 and interactions with gender. RESULTS: There was an interaction between prenatal depression and gender (P=0.027) and between postnatal depression and gender (P=0.027) for offspring depression at 18. Following adjustment in pre-natally depressed mothers, the odds ratio for offspring depression at 18 was 1.55 (95% c.i. 1.03-2.34) for girls and 0.54 (0.23-1.26) for boys. In post-natally depressed mothers, the odds ratio for offspring depression at 18 was 1.15 (0.70-1.89) in girls and 3.13 (1.52-6.45) in boys. However there was no evidence for interaction between prenatal or postnatal depression and gender (P=0.559 and 0.780 respectively) for offspring depression at 12. LIMITATIONS: As expected with this large cohort spanning over 18 years, there was loss-to-follow-up. CONCLUSIONS: This is the first evidence in humans that increased vulnerability of female fetuses to maternal stress responses during pregnancy persists into adolescence. One explanation for gender differences emerging later is more depressive symptomatology is attributed to heritable risk at 12, whereas biological processes involved in brain development at 18 may be influenced by foetal programming. If replicated, this study has potential to help understand intergenerational transmission of depression, a leading cause of morbidity worldwide
Long-term carcinogenicity of pan masala in Swiss mice
Carcinogenicity of pan masala, a dry powdered chewing mixture of areca nut, catechu, lime, spices and flavoring agents was evaluated by means of the long-term animal bio-assay 6- to 7-week old male and female S/RVCri mice were divided randomly into intermediate and lifetime exposure groups and fed normal diet without pan masala - (zero dose) or diet containing 2.5% and 5% pan masala. Animals in the intermediate-exposure group (n = 10/gender/dose group) were killed after 6, 12 or 18 months of treatment, while those in the lifetime-exposure group (n = 54/gender/dose group) were killed when moribund or at the termination of the experiment at 24 months. Several tissues were processed for histopathological examination. The body weight and survival rate of mice fed pan masala were lower than that of the controls. Histopathological observations of tissues from control animals did not reveal any neoplastic alterations. However, lifetime feeding of pan masala induced adenoma of the liver, stomach, prostate and sebaceous glands, also forestomach papilloma, liver hamartoma, hepatoma and hemangioma, carcinoma of the forestomach, adenocarcinoma of the lung and liver, and testicular lymphoma. Neoplastic lesions appeared mainly in the liver (n = 13), stomach (n = 3) and lung (n = 8). Lung adenocarcinoma, the most frequent malignant tumor type, was observed in 2/120 mice in the intermediate-exposure group and in 8/216 animals in the lifetime-exposure group. Statistical analysis of tumor-induction data revealed a significant dose-related increase in lung adenocarcinomas but not in liver and stomach neoplasms indicating that lung is the major target tissue for the carcinogenic action of pan masala
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