361 research outputs found

    The effect of body mass index on global brain volume in middle-aged adults: a cross sectional study

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    BACKGROUND: Obesity causes or exacerbates a host of medical conditions, including cardiovascular, pulmonary, and endocrine diseases. Recently obesity in elderly women was associated with greater risk of dementia, white matter ischemic changes, and greater brain atrophy. The purpose of this study was to determine whether body type affects global brain volume, a marker of atrophy, in middle-aged men and women. METHODS: T1-weighted 3D volumetric magnetic resonance imaging was used to assess global brain volume for 114 individuals 40 to 66 years of age (average = 54.2 years; standard deviation = 6.6 years; 43 men and 71 women). Total cerebrospinal fluid and brain volumes were obtained with an automated tissue segmentation algorithm. A regression model was used to determine the effect of age, body mass index (BMI), and other cardiovascular risk factors on brain volume and cognition. RESULTS: Age and BMI were each associated with decreased brain volume. BMI did not predict cognition in this sample; however elevated diastolic blood pressure was associated with poorer episodic learning performance. CONCLUSION: These findings suggest that middle-aged obese adults may already be experiencing differentially greater brain atrophy, and may potentially be at greater risk for future cognitive decline

    Aerobic Exercise during Pregnancy and Presence of Fetal-Maternal Heart Rate Synchronization

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    It has been shown that short-term direct interaction between maternal and fetal heart rates may take place and that this interaction is affected by the rate of maternal respiration. The aim of this study was to determine the effect of maternal aerobic exercise during pregnancy on the occurrence of fetal-maternal heart rate synchronization.In 40 pregnant women at the 36th week of gestation, 21 of whom exercised regularly, we acquired 18 min. RR interval time series obtained simultaneously in the mothers and their fetuses from magnetocardiographic recordings. The time series of the two groups were examined with respect to their heart rate variability, the maternal respiratory rate and the presence of synchronization epochs as determined on the basis of synchrograms. Surrogate data were used to assess whether the occurrence of synchronization was due to chance.In the original data, we found synchronization occurred less often in pregnancies in which the mothers had exercised regularly. These subjects also displayed higher combined fetal-maternal heart rate variability and lower maternal respiratory rates. Analysis of the surrogate data showed shorter epochs of synchronization and a lack of the phase coordination found between maternal and fetal beat timing in the original data.The results suggest that fetal-maternal heart rate coupling is present but generally weak. Maternal exercise has a damping effect on its occurrence, most likely due to an increase in beat-to-beat differences, higher vagal tone and slower breathing rates

    Critical Appraisal of Four IL-6 Immunoassays

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    BACKGROUND: Interleukin-6 (IL-6) contributes to numerous inflammatory, metabolic, and physiologic pathways of disease. We evaluated four IL-6 immunoassays in order to identify a reliable assay for studies of metabolic and physical function. Serial plasma samples from intravenous glucose tolerance tests (IVGTTs), with expected rises in IL-6 concentrations, were used to test the face validity of the various assays. METHODS AND FINDINGS: IVGTTs, administered to 14 subjects, were performed with a single infusion of glucose (0.3 g/kg body mass) at time zero, a single infusion of insulin (0.025 U/kg body mass) at 20 minutes, and frequent blood collection from time zero to 180 minutes for subsequent Il-6 measurement. The performance metrics of four IL-6 detection methods were compared: Meso Scale Discovery immunoassay (MSD), an Invitrogen Luminex bead-based multiplex panel (LX), an Invitrogen Ultrasensitive Luminex bead-based singleplex assay (ULX), and R&D High Sensitivity ELISA (R&D). IL-6 concentrations measured with MSD, R&D and ULX correlated with each other (Pearson Correlation Coefficients r = 0.47-0.94, p<0.0001) but only ULX correlated (r = 0.31, p = 0.0027) with Invitrogen Luminex. MSD, R&D, and ULX, but not LX, detected increases in IL-6 in response to glucose. All plasma samples were measurable by MSD, while 35%, 1%, and 4.3% of samples were out of range when measured by LX, ULX, and R&D, respectively. Based on representative data from the MSD assay, baseline plasma IL-6 (0.90 ± 0.48 pg/mL) increased significantly as expected by 90 minutes (1.29 ± 0.59 pg/mL, p = 0.049), and continued rising through 3 hours (4.25 ± 3.67 pg/mL, p = 0.0048). CONCLUSION: This study established the face validity of IL-6 measurement by MSD, R&D, and ULX but not LX, and the superiority of MSD with respect to dynamic range. Plasma IL-6 concentrations increase in response to glucose and insulin, consistent with both an early glucose-dependent response (detectable at 1-2 hours) and a late insulin-dependent response (detectable after 2 hours)

    Polyploidization as a Retraction Force in Plant Genome Evolution: Sequence Rearrangements in Triticale

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    BACKGROUND: Polyploidization is a major evolutionary process in plants where hybridization and chromosome doubling induce enormous genomic stress and can generate genetic and epigenetic modifications. However, proper evaluation of DNA sequence restructuring events and the precise characterization of sequences involved are still sparse. METHODOLOGY/PRINCIPAL FINDINGS: Inter Retrotransposons Amplified Polymorphism (IRAP), Retrotransposons Microsatellite Amplified Polymorphism (REMAP) and Inter Simple Sequence Repeat (ISSR) largely confirmed the absence of any intraspecific variation in wheat, rye and triticale. The comparative analysis of banding profiles between wheat and rye inbred lines revealed 34% of monomorphic (common to both parental species) bands for the ten different primer combinations used. The analysis of triticale plants uncovered nearly 51% of rearranged bands in the polyploid, being the majority of these modifications, due to the loss of rye bands (83%). Sequence analysis of rye fragments absent in triticale revealed for instance homology with hydroxyproline-rich glycoproteins (HRGP), a protein that belongs to a major family of inducible defence response proteins. Conversely, a wheat-specific band absent in triticale comprises a nested structure of copia-like retrotransposons elements, namely Claudia and Barbara. Sequencing of a polyploid-specific band (absent in both parents) revealed a microsatellite related sequence. Cytological studies using Fluorescent In Situ Hybridization (FISH) with REMAP products revealed a widespread distribution of retrotransposon and/or microsatellite flanking sequences on rye chromosomes, with a preferential accumulation in heterochromatic sub-telomeric domains. CONCLUSIONS/SIGNIFICANCE: Here, we used PCR-based molecular marker techniques involving retrotransposons and microsatellites to uncover polyploidization induced genetic restructuring in triticale. Sequence analysis of rearranged genomic fragments either from rye or wheat origin showed these to be retrotransposon-related as well as coding sequences. Further FISH analysis revealed possible chromosome hotspots for sequence rearrangements. The role of chromatin condensation on the origin of genomic rearrangements mediated by polyploidization in triticale is also discussed

    Fostering implementation of health services research findings into practice: a consolidated framework for advancing implementation science

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    Abstract Background Many interventions found to be effective in health services research studies fail to translate into meaningful patient care outcomes across multiple contexts. Health services researchers recognize the need to evaluate not only summative outcomes but also formative outcomes to assess the extent to which implementation is effective in a specific setting, prolongs sustainability, and promotes dissemination into other settings. Many implementation theories have been published to help promote effective implementation. However, they overlap considerably in the constructs included in individual theories, and a comparison of theories reveals that each is missing important constructs included in other theories. In addition, terminology and definitions are not consistent across theories. We describe the Consolidated Framework For Implementation Research (CFIR) that offers an overarching typology to promote implementation theory development and verification about what works where and why across multiple contexts. Methods We used a snowball sampling approach to identify published theories that were evaluated to identify constructs based on strength of conceptual or empirical support for influence on implementation, consistency in definitions, alignment with our own findings, and potential for measurement. We combined constructs across published theories that had different labels but were redundant or overlapping in definition, and we parsed apart constructs that conflated underlying concepts. Results The CFIR is composed of five major domains: intervention characteristics, outer setting, inner setting, characteristics of the individuals involved, and the process of implementation. Eight constructs were identified related to the intervention (e.g., evidence strength and quality), four constructs were identified related to outer setting (e.g., patient needs and resources), 12 constructs were identified related to inner setting (e.g., culture, leadership engagement), five constructs were identified related to individual characteristics, and eight constructs were identified related to process (e.g., plan, evaluate, and reflect). We present explicit definitions for each construct. Conclusion The CFIR provides a pragmatic structure for approaching complex, interacting, multi-level, and transient states of constructs in the real world by embracing, consolidating, and unifying key constructs from published implementation theories. It can be used to guide formative evaluations and build the implementation knowledge base across multiple studies and settings.http://deepblue.lib.umich.edu/bitstream/2027.42/78272/1/1748-5908-4-50.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78272/2/1748-5908-4-50-S1.PDFhttp://deepblue.lib.umich.edu/bitstream/2027.42/78272/3/1748-5908-4-50-S3.PDFhttp://deepblue.lib.umich.edu/bitstream/2027.42/78272/4/1748-5908-4-50-S4.PDFhttp://deepblue.lib.umich.edu/bitstream/2027.42/78272/5/1748-5908-4-50.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/78272/6/1748-5908-4-50-S2.PDFPeer Reviewe

    Increased risk of malignancies in a population-based study of 818 soft-tissue sarcoma patients

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    Soft-tissue sarcomas (STS) have been associated with various rare cancer syndromes and occur at increased frequencies in survivors of childhood cancer. Also adult patients with STS have been suggested to be at an increased risk of additional malignancies. After exclusion of syndrome-associated and radiation-induced sarcomas, we studied multiple primary malignancies in a population-based cohort of 818 patients with primary STS of the extremities and the trunk wall. In total, 203 other malignancies developed in 164 (20%) patients median 10 (0–32) years before and median 4 (0–35) years after the sarcoma diagnosis. Standardised morbidity ratios (SMRs) were determined for primary malignancies following a STS. Hereby individuals who had developed a STS were identified to be at increased risk of second primary malignancies (SMR for all malignant tumours=1.3; 95% CI=1.0–1.5; P=0.02) with STS being the only specific tumour type that occurred at an increased risk (SMR=17.6; 95% CI=8.1–33.5; P<0.001). Hence, this population-based series demonstrates a high frequency of second primary tumours among STS patients and indicates a particularly increased risk of developing a new STS

    Multiple primary malignancies and subtle mucocutaneous lesions associated with a novel PTEN gene mutation in a patient with Cowden syndrome: Case report

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    <p>Abstract</p> <p>Background</p> <p>Cowden syndrome (CS) is a cancer predisposition syndrome associated with increased risk of breast, thyroid, and endometrial cancers, and is characterized by development of benign mucocutaneous lesions.</p> <p>Case presentation</p> <p>Here we report on a 58-year-old woman with multiple primary malignancies and subtle mucocutaneous lesions such as small polyps and wart-like papulas. Over a period of 23 years, she developed various malignant neoplasms including thyroid, ovarian, stomach, and colon carcinomas, and a benign meningioma. Direct sequencing analysis of the <it>PTEN </it>gene revealed a novel germline mutation (c.438delT, p.Leu146X).</p> <p>Conclusion</p> <p>This case demonstrates that Cowden syndrome is a multi-system disease that can result in the development of multiple malignant and benign tumors.</p

    Higher education delays and shortens cognitive impairment. A multistate life table analysis of the US Health and Retirement Study

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    Improved health may extend or shorten the duration of cognitive impairment by postponing incidence or death. We assess the duration of cognitive impairment in the US Health and Retirement Study (1992–2004) by self reported BMI, smoking and levels of education in men and women and three ethnic groups. We define multistate life tables by the transition rates to cognitive impairment, recovery and death and estimate Cox proportional hazard ratios for the studied determinants. 95% confidence intervals are obtained by bootstrapping. 55 year old white men and women expect to live 25.4 and 30.0 years, of which 1.7 [95% confidence intervals 1.5; 1.9] years and 2.7 [2.4; 2.9] years with cognitive impairment. Both black men and women live 3.7 [2.9; 4.5] years longer with cognitive impairment than whites, Hispanic men and women 3.2 [1.9; 4.6] and 5.8 [4.2; 7.5] years. BMI makes no difference. Smoking decreases the duration of cognitive impairment with 0.8 [0.4; 1.3] years by high mortality. Highly educated men and women live longer, but 1.6 years [1.1; 2.2] and 1.9 years [1.6; 2.6] shorter with cognitive impairment than lowly educated men and women. The effect of education is more pronounced among ethnic minorities. Higher life expectancy goes together with a longer period of cognitive impairment, but not for higher levels of education: that extends life in good cognitive health but shortens the period of cognitive impairment. The increased duration of cognitive impairment in minority ethnic groups needs further study, also in Europe

    Long Chain Polyunsaturated Fatty Acid Supplementation in Infancy Reduces Heart Rate and Positively Affects Distribution of Attention

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    A double-blind, randomized, controlled, parallel-group prospective trial was conducted to determine whether a dose-response existed for four different levels of docosahexaenoic acid (DHA) supplementation on the cognitive performance of infants. A total of 122 term infants were fed one of four different formulas varying in their DHA composition (0.00%, 0.32%, 0.64% and 0.96% of total fatty acids as DHA) from birth to 12 months. The three DHA-supplemented formulas also contained 0.64% of total fatty acids as arachidonic acid (ARA, 20:4n-6). Infants were tested at 4, 6, and 9 months of age on a visual habituation protocol that yielded both behavioral and psychophysiological indices of attention. Infants in all DHA+ARA-supplemented conditions had lower heart rates than those in the unsupplemented condition; there was no dose-response for this effect. The distribution of time that infants spent in different phases of attention (a cognitive index derived from the convergence of behavioral and cardiac responses) varied as a function of dosage. Infants supplemented at the two lower DHA doses spent proportionately more time engaged in active stimulus processing than infants fed the unsupplemented formula, while infants fed the highest dose were intermediate and did not differ from any other group
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