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Biomarkers of biogeochemical carbon cycling at three aquifer sites in Bangladesh / Biomarkers in three Bangladesh aquifer sitesSan Pedro, Reisa Joy January 2019 (has links)
The role of aquifer microorganisms in controlling arsenic contamination of Bangladesh aquifers via oxidation of organic carbon coupled with reduction of sedimentary iron oxyhydroxides and concomitant arsenic dissolution is generally accepted. What remains to be ascertained is the in situ biogeochemical mechanisms of cycling different carbon sources and directly relating indigenous microbiota to arsenic release.
Using biomarker fingerprint approaches, this dissertation expanded the presently growing research in the biogeochemical carbon cycling controlling arsenic contamination in Bangladesh aquifers. Comprehensive profiles of microbial cell membrane components (PLFA and sterols) at three different aquifers tested the regional distribution of aquifer microbial community abundance, structure, and organic input potential across Araihazar. The highly variable bulk viable microbial biomass observed across these three sites confer both regional-scale and localized heterogeneous distributions of in-aquifer microbial communities which control carbon cycling in the aquifer. The lack of correlation between PLFA biomarkers and dissolved arsenic challenges the assumption that greater extent of microbial community metabolism results in an increase in arsenic in groundwater. Natural abundance radiocarbon isotope Δ14C analysis of cell membrane PLFA and available carbon pools (SOC, DOC, DIC) confirmed that young organic carbon substrates are being cycled at two of the three sites investigated here. This corroborates previous reports at nearby sites (Site B and F) thereby contributing to a well-constrained carbon source which actively support microbial metabolism over a regional scale. Sterol biomarker distributions were characterized to determine potential sources of organic input into the aquifer. In particular, the importance of raw human and/or animal sewage waste as a source of labile carbon was assessed by measuring the faecal biomarker Coprostanol and comparing its abundance to other sources of biogenic sterols using sewage input proxies (Sewage Contamination Index, Coprostanol/Cholesterol ratio). This was motivated by previous findings which correlated sewage contamination with dissolved arsenic at depth at nearby sites. While sewage contamination was low in the shallow aquifers at these sites, it is more likely that plant organic matter supported the elevated microbial abundance at shallow depths. On the other hand, evidence presented in this project suggests that sewage contamination intrudes into deeper aquifers (e.g. buried Pleistocene) and contributes to the vulnerability of previous pristine aquifers to future arsenic contamination. / Thesis / Master of Science (MSc)
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Maternal body adiposity changes during pregnancy and association with cardiometabolic status and adverse outcomes in a randomized nutrition+exercise intervention trial / Maternal adiposity changes during pregnancyMaran, Atherai January 2020 (has links)
Rationale & Background: Gaining excessive adiposity in pregnancy is associated with altered cardiometabolic profile and adverse pregnancy outcomes. Lifestyle interventions may reduce excess weight gain, but the effect on fat gain is unclear. Our study explored this question by 1) comparing measures of body fat (BF) by bioelectrical impedance analysis (BIA) and 4-site skinfold thickness (SFT); 2) assessing the impact of a nutrition+exercise intervention on adiposity changes; 3) elucidating associations between adiposity changes and cardiometabolic biomarkers and adverse pregnancy outcomes. Study Design: Participants randomized to receive a high dairy protein diet and exercise program (intervention) or standard care (control) in the Be Healthy in Pregnancy RCT (NCT 01689961) had adiposity measured at 12-17, 26-28, and 36-38 weeks gestation by BIA (%BF) and SFT (sum and %BF), and at 6 months postpartum also by DXA. Fasted blood samples collected at 12-17 and 36-38 weeks gestation were analyzed for glucose, lipid profile, insulin, leptin, adiponectin, and CRP. Pregnancy outcomes were abstracted from medical charts.
Results: In 181 participants, BIA %BF and SFT %BF had good agreement in early pregnancy and postpartum, but low agreement in late pregnancy. Adiposity changes across pregnancy were similar between study arms but were greater in normal weight compared to overweight women. Insulin and leptin were negatively associated with change in SFT (sum and %BF). Triglycerides were negatively associated with change in BIA %BF, while HDL was positively associated. Neither caesarean section nor operative vaginal delivery were associated with adiposity change.
Conclusion: Adiposity measured by sum of SFT and BIA %BF increased across pregnancy but was not influenced by the diet+exercise intervention. Associations of adiposity change with cardiometabolic biomarkers varied between measurement tools. The lack of adiposity measurement tools appropriate across pregnancy and in clinical settings presents a concern for assessing clinical responses to adiposity change across pregnancy. / Thesis / Master of Science (MSc) / Pregnancy is associated with a natural gain in body fat, but it can reach excessive amounts. Excess body fat is of clinical consequence as it is associated with poor cardiovascular health and abnormal pregnancy outcomes. Improving diet and physical activity habits may reduce excess weight gain, but little is known about how it influences fat gained during pregnancy. In our study body fat gain during pregnancy was similar between the lifestyle intervention and control groups. However, entering pregnancy with greater BMI was associated with less fat gain during pregnancy. Changes in body fat influenced cardiovascular blood markers, but results differed between body fat assessment tools. We also found that methods to measure body fat produce different results at different stages of pregnancy. Our findings provide insight on the factors that influence fat gain during pregnancy and highlight the need for better tools to measure body fat accurately in pregnancy.
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Studying stress-associated non-invasive biomarkers in Japanese macaques / ニホンザルにおけるストレス関連非侵襲的バイオマーカーの研究ネルソン, ブロシェイ ジュニア 23 March 2023 (has links)
付記する学位プログラム名: 霊長類学・ワイルドライフサイエンス・リーディング大学院 / 京都大学 / 新制・課程博士 / 博士(理学) / 甲第24467号 / 理博第4966号 / 新制||理||1709(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)准教授 Huffman Michael Alan, 教授 古市 剛史, 教授 今井 啓雄 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
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A smartphone camera reveals an ‘invisible’ Parkinsonian tremor: a potential pre-motor biomarker?Williams, S., Fang, H., Alty, J., Qahwaji, Rami S.R., Patel, P., Graham, C.D. 21 September 2018 (has links)
no / There are a wide variety of ways to objectively detect neurological signs, but these either require special hard-ware (such as wearable technology) or patient behaviour change (such as engagement with smartphone tasks) [2]. Neither constraint applies to the technology of computer vision, which is the processing of single or multiple camera images by computer to automatically derive useful information. The only equipment involved is ubiquitous: camera and computer.We report a computer vision-enhanced video sequence from a 68-year-old man, diagnosed with idiopathic Parkinson’s disease 2 years previously.
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The Effects of Low Energy Availability and High-Impact Exercise on Bone and Body CompositionSterringer, Trisha Marie 28 May 2024 (has links)
Low energy availability (LEA) has been identified as the underlying etiology of the Female Athlete Triad and Relative Energy Deficiency in Sport (REDs) syndrome. The term energy availability (EA) describes the amount of dietary energy intake (EI) that is remaining to support physiological function after accounting for the energy cost of exercise. Exposure to LEA stimulates metabolic adaptations that may disrupt certain biological systems, such as endocrine function, and impair sports performance. Controlled laboratory research has shown suppression of bone formation biomarkers with accelerated rates of bone resorption after only three to five days of LEA in active females. Correcting LEA by increasing EI or decreasing exercise energy expenditure (EEE) may not be feasible for all athletes and additional approaches for protecting bone health during LEA require further investigation. Recent evidence suggests that brief bouts of high-impact exercise attenuate the increased rate of bone resorption in females with diet-induced LEA. However, it is unknown whether similar exercises have a protective effect on bone health when LEA is induced through a combination of dietary restriction and exercise. A gap also remains in the understanding of how EA fluctuates throughout the athletic season and what potential effect that has on body composition and performance outcomes. To address these gaps, we conducted two studies to investigate the interactions of EA, bone health, and body composition. The first investigation employed a randomized crossover design in which female runners underwent two, five-day experimental conditions of LEA consisting of dietary restriction and daily running (EA = 15 kcal·kg FFM-1·day-1). During one of the experimental conditions, participants also completed a bout of 50 jumping exercises daily. Serum markers of bone resorption (C-terminal cross-linking telopeptide of type 1 collagen [CTX-I]), bone formation (N-terminal propeptide of type 1 procollagen [PINP]), and hormonal profiles were compared between baseline and post-intervention using linear mixed effects modeling. We hypothesized that daily high-impact exercise would have a positive effect on bone by attenuating the rise in bone resorption. In contrast to our hypothesis, bone resorption marker CTX-I increased following both LEA conditions (+12%, P=0.004) with no difference in the response between the jumping and non-jumping conditions. Bone formation was not suppressed following either LEA condition. Concentrations of free triiodothyronine (T3), insulin-like growth factor-1, leptin, and insulin decreased in response to five days of LEA independent of condition (P<0.05); however, when taking into account condition, the decrease in free T3 was only statistically significant following the LEA condition without jumping (-27%, P=0.022, Cohen's d=0.87). Our findings suggest that high-impact jumping exercises are not an effective countermeasure to protect bone health during short-term LEA in female runners who continue to run routinely. In a second study, we conducted a longitudinal, observational study in collegiate male soccer players to investigate seasonal changes in EA and body composition. Measurements of EA, body composition, and sports performance were assessed at the start and end of the non-championship Spring athletic season. We hypothesized that EA would be positively associated with changes in body composition at the end of the three-month season. Despite most athletes reporting desires to gain total and/or lean body mass, no changes in EA or body composition were detected at the end of the season compared to the start. Furthermore, sports performance and bone density improved across the season regardless of individual changes in EA. These results indicate EA of collegiate male soccer players during the Spring season is sufficient to maintain current body composition and improve sports performance, but insufficient to support total and/or lean body mass gains. / Doctor of Philosophy / Adequate energy intake (EI) is essential for fueling athletic performance and supporting general health. Low energy availability (LEA) occurs when EI is insufficient to meet the energy demands of both exercise and basic health functions. Athletes with LEA may experience various repercussions such as suppressed metabolism, hormonal changes, and impaired bone health. Training adaptations may also be impaired by LEA, thereby affecting athletic performance. Daily high-impact jumping exercises have been shown to have a positive effect on bone health in women, even during periods of LEA caused by dietary restriction. However, this type of exercise intervention has not been tested in combination with other forms of daily exercise in women exposed to a controlled period of LEA. The purpose of these studies was to examine how exercise and EA affect bone health and body composition in recreational and competitive athletes. The first study investigated the effects of daily jumping exercises on markers of bone formation and breakdown during five days of LEA in female runners. The completion of 50 jumping exercises each day along with running on a treadmill was not shown to provide additional bone-protective benefits during LEA compared to running alone, as shown by similar rates of bone breakdown observed under both conditions. The second study investigated whether changes occur in EA or body composition in male collegiate soccer players over an athletic season. Despite most of the athletes reporting desires to gain weight or muscle during the season, there were no differences in body composition or EA at the end of the season compared to the start. However, there were significant improvements in aerobic fitness, relative strength, and bone density throughout the season.
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Mucosal biomarkers of colorectal cancer risk do not increase at 6 months following sleeve gastrectomy, unlike gastric bypassKant, P., Perry, S.L., Dexter, S.P., Race, Amanda D., Loadman, Paul 15 October 2013 (has links)
Yes / Objective
The hypothesis that sleeve gastrectomy (SG) is not associated with an increase in mucosal colorectal cancer (CRC) biomarkers, unlike Roux-en-Y gastric bypass (RYGB), was tested.
Design and Methods
Rectal mucosa, blood, and urine were obtained from morbidly obese patients (n = 23) before and after (median 28 months) SG, as well as from nonobese controls (n = 20). Rectal epithelial cell mitosis and apoptosis, crypt size/fission, and pro-inflammatory gene expression were measured, as well as systemic inflammatory biomarkers, including C-reactive protein (CRP).
Results
The mean pre-operative body mass index in SG patients was 65.7 kg/m2 (24.7 kg/m2 in controls). Mean excess weight loss post-SG was 38.2%. There was a significant increase in mitosis frequency, crypt size, and crypt fission (all P < 0.01) in SG patients versus controls, as well as evidence of a chronic inflammatory state (raised CRP and mononuclear cell p65 NFκB binding), but there was no significant change in these biomarkers after SG, except CRP reduction. Macrophage migration inhibitory factor mRNA levels were increased by 39% post-SG (P = 0.038).
Conclusions
Mucosal biomarkers of CRC risk do not increase at 6 months following SG, unlike RYGB. Biomarkers of rectal crypt proliferation and systemic inflammation are increased in morbidly obese patients compared with controls.
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Evaluation of nipple aspirate fluid as a diagnostic tool for early detection of breast cancerShaheed, Sadr-ul, Tait, C., Kyriacou, K., Linforth, R., Salhab, M., Sutton, Chris W. 11 January 2018 (has links)
Yes / There has been tremendous progress in detection of breast cancer in postmenopausal women, resulting in two-thirds
of women surviving more than 20 years after treatment. However, breast cancer remains the leading cause of cancerrelated
deaths in premenopausal women. Breast cancer is increasing in younger women due to changes in life-style
as well as those at high risk as carriers of mutations in high-penetrance genes. Premenopausal women with breast
cancer are more likely to be diagnosed with aggressive tumours and therefore have a lower survival rate. Mammography
plays an important role in detecting breast cancer in postmenopausal women, but is considerably less sensitive
in younger women. Imaging techniques, such as contrast-enhanced MRI improve sensitivity, but as with all imaging
approaches, cannot differentiate between benign and malignant growths. Hence, current well-established detection
methods are falling short of providing adequate safety, convenience, sensitivity and specificity for premenopausal
women on a global level, necessitating the exploration of new methods. In order to detect and prevent the disease
in high risk women as early as possible, methods that require more frequent monitoring need to be developed. The
emergence of “omics” strategies over the last 20 years, enabling the characterisation and understanding of breast cancer
at the molecular level, are providing the potential for long term, longitudinal monitoring of the disease. Tissue and
serum biomarkers for breast cancer stratification, diagnosis and predictive outcome have emerged, but have not successfully
translated into clinical screening for early detection of the disease. The use of breast-specific liquid biopsies,
such as nipple aspirate fluid (NAF), a natural secretion produced by breast epithelial cells, can be collected non-invasively
for biomarker profiling. As we move towards an age of active surveillance, home-based liquid biopsy collection
kits are increasingly being applied and these could provide a paradigm shift where NAF biomarker profiling is used for
routine breast health monitoring. The current status of established and newly emerging imaging techniques for early
detection of breast cancer and the potential for alternative biomarker screening of liquid biopsies, particularly those
applied to high-risk, premenopausal women, will be reviewed. / Proteomics research was supported by Yorkshire Cancer Research projects, BPP047 and B381PA, and co-funded by the European Regional Development Fund and the Republic of Cyprus through the Research Promotion Foundation projects ΥΓΕΙΑ/ΒΙΟΣ/0311(ΒΙΕ/07) and NEKYP/0311/17.
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An exploratory LC-MS/MS method for quantitative analysis of acylcarnitines in whole blood originating from forensic autopsy cases / En explorativ LC-MS/MS metod för att kvantitativt analysera acylkarnitiner i helblod taget från forensiska obduktionsärendenPeterson, Jenny January 2024 (has links)
Forensics face a complicated problem when evaluating intoxications induced by opioids and non – intoxications of opioid abusers since the in vitro concentrations of the said opioid overlap. Researchers found that acylcarnitines role as biomarkers for a diversity of diseases may also be used as biomarkers postmortem, easing the complications that occurs of evaluating the cause of death. A reversed phase ultra high performance liquid chromatography (UHPLC) method in combination with mass spectrometer detection was developed for a quantitative analysis of different acylcarnitines in authentic blood samples. The hypothesis investigated was the altercation of acylcarnitine concentration depending on the cause of death, specifically when induced by opioids. Separation was achieved using ACQUITY UPLC HSS T3 1.8 µm (2.1 x 100 mm) Waters column along with a gradient elution consisting of Mobile phase A: 0.05% HFo in 10 mM Ammoniumformate and Mobile phase B: 0.05% HFo in Methanol. Flowrate was 0.4 mL/min. The method was validated in respect to linearity and range, accuracy, precision, LOD and LOQ as well as stability and degradation of acylcarnitines. Linearity was acceptable with R2 – values for all the substances. Results from the authentic sample analysis showed no statistically significant difference between the investigated groups based on Kruskal – Wallis non-parametric tests and median comparison, however a trend in the data was found correlating to the investigated hypothesis suggesting it may be true.
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Examining the role of hypertension-induced mechanotransduction on vascular smooth muscle cells and vascular calcificationMoon, Jessica 13 August 2024 (has links) (PDF)
Cardiovascular disease is the world’s number 1 killer. The cardiovascular system helps to pump blood throughout the human body and maintain a systemic balance. However, medial vascular calcification results when this system becomes off balance, such as in cases of high blood pressure leading to hypertension. Many factors are involved in this process, but the most important is the vascular smooth muscle cell phenotypic switch to osteoblast-like cells. When vascular smooth muscle cells are subject to mechanical stimuli, mechanotransduction occurs, causing an intracellular signaling cascade leading to a phenotypic switch associated with the Wnt signaling pathway and osteogenic markers. There is a lack of understanding of the defined linkages of pathways that lead to the development of the osteoblast-like cell type. Therefore, examining human aortic smooth muscle cells under hypertensive conditions could decrease the prevalence of cardiovascular disease worldwide.
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Pro-Tumorigenic role of ETS-related gene (ERG) in precursor prostate cancer lesionsLorenzoni, Marco 14 October 2019 (has links)
Prostate cancer (PCa) is the second most common cancer in men with more than 1 million new cases worldwide each year. While some of the genomic, genetic and molecular events characterizing PCa have been functionally associated with tumor onset, development and resistance to therapy, the meaning of many other molecular alterations remains poorly understood. Recent development of organoids technology and prostate organoid cultures has established an innovative and valuable model for the study of adult tissue homeostasis, physiology and disease. In this project we combined prostate organoids technology with genetic engineering and CLICK-chemistry coupled Mass Spectrometry approaches in order to better characterize molecular features of wild type and genetically engineered mouse prostate organoids modeling early steps of human prostate tumorigenesis. In details, by manipulating mPrOs to proxy ETS-related gene (ERG) precursor PIN/HGPIN lesions of human prostate, we identified possible novel pro-tumorigenic roles of ERG which unleashes cells proliferation from the tight control of growth stimuli, and, even more interesting, corrupts immune system components to escape immune surveillance. In conclusion, this project shows that coupling innovative biological systems and technological approaches can lead to significant improvements in the analysis and understanding of disease mechanisms.
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