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Effects of weight loss on postprandial vascular function have not been studied so far. We therefore examined (i) effects of diet-induced weight loss on postprandial changes in various vascular function markers after consumption of a mixed meal and (ii) differences between normal-weight and abdominally obese men of comparable age at baseline and after weight loss.Fifty-four apparently healthy abdominally obese (waist circumference: 102-110 cm) and 25 normal-weight men (waist circumference:94 cm) participated. The abdominally obese men were randomly allocated to a diet-induced weight-loss program or a no-weight loss control group. Men assigned to the weight-loss program followed a calorie-restricted diet for six weeks targeting a waist circumference of less than 102 cm, followed by a weight-maintenance period for two weeks. The control group maintained their habitual diet and physical activity levels. Measurements were performed before and two hours after consumption of the test meal consisting of two muffins (containing 56.6 g fat) and 300 mL low-fat milk.The mean weight loss was 10.3 kg in the weight-loss compared with the control group. The postprandial change in flow-mediated vasodilation of the brachial artery (FMD) was significantly higher at baseline in normal-weight as compared with the postprandial change in abdominally obese men (1.89 ± 2.52 versus 0.48 ± 2.50 percentage points; P = 0.027). However, no differences in postprandial changes were observed in the abdominally obese men after weight loss compared with the control treatment. Also, weight reduction did not affect postprandial changes in carotid-to-femoral pulse wave velocity, retinal microvascular caliber properties, or plasma markers of microvascular endothelial function. Even though postprandial increases in triacylglycerol (P = 0.028), insulin (P = 0.029) and C-peptide concentrations (P 0.001) were reduced in the abdominally obese men following weight loss, postprandial changes in FMD at the end of the weight-loss treatment were still more unfavorable as compared with those observed in normal-weight individuals.In this trial with abdominally obese men, we did not find effects of diet-induced weight loss on postprandial changes in vascular endothelial function, arterial stiffness and markers of microvascular function. This trial was registered on ClinicalTrials.gov under study number NCT01675401.

BACKGROUND: Only a limited number of studies have examined the vascular and postprandial effects of α-linolenic acid (ALA, C18:3n-3). Therefore, we performed a well-controlled trial focusing specifically on the effects of ALA on vascular function and metabolic risk markers during the fasting and postprandial phase in untreated (pre-)hypertensive individuals.METHODS: In a double-blind randomized, placebo-controlled parallel study, 59 overweight and obese adults (40 men and 19 women, aged 60 ± 8 years) with a high-normal blood pressure or mild (stage I) hypertension consumed daily either 10 g of refined cold-pressed flaxseed oil, providing 4.7 g ALA (n = 29), or 10 g of high-oleic sunflower (control) oil (n = 30) for 12 weeks.RESULTS: As compared with the high-oleic oil control, intake of flaxseed oil did not change brachial artery flow-mediated vasodilation, carotid-to-femoral pulse wave velocity, retinal microvascular calibers and plasma markers of microvascular endothelial function during the fasting and postprandial phase. Fasting plasma concentrations of free fatty acid (FFA) and TNF-α decreased by 58 μmol/L (P = 0.02) and 0.14 pg/mL (P = 0.03), respectively. No differences were found in other fasting markers of lipid and glucose metabolism, and low-grade systemic inflammation. In addition, dietary ALA did not affect postprandial changes in glucose, insulin, triacylglycerol, FFA and plasma inflammatory markers after meal intake.CONCLUSION: A high intake of ALA, about 3-5 times the recommended daily intake, for 12 weeks decreased fasting FFA and TNF-α plasma concentrations. No effects were found on other metabolic risk markers and vascular function during the fasting and postprandial phase in untreated high-normal and stage I hypertensive individuals.

Background The influence of different biological agents on the rate of orthodontic tooth movement (OTM) has been extensively reviewed in animal studies with conflicting results. These findings cannot be extrapolated from animals to humans. Therefore, we aimed to systematically investigate the most up-to-date available evidence of human studies regarding the effect of the administration of different biological substances on the rate of orthodontic tooth movement. Methods A total of 8 databases were searched until the 16th of June 2020 without restrictions. Controlled randomized and non-randomized human clinical studies assessing the effect of biological substances on the rate of OTM were included. ROBINS-I and the Cochrane Risk of Bias tools were used. Reporting of this review was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results A total of 11 studies (6 randomized clinical trials and 5 prospective clinical trials) were identified for inclusion. Local injections of prostaglandin E1 and vitamin C exerted a positive influence on the rate of OTM; vitamin D showed variable effects. The use of platelet-rich plasma and its derivatives showed inconsistent results, while the local use of human relaxin hormone showed no significant effects on the rate of OTM. Limitations The limited and variable observation periods after the administration of the biological substances, the high and medium risk of bias assessment for some included studies, the variable concentrations of the assessed biological agents, the different experimental designs and teeth evaluated, and the variety of measurement tools have hampered the quantitative assessment of the results as originally planned. Conclusions and implications Despite the methodological limitations of the included studies, this systematic review provides an important overview of the effects of a variety of biological agents on the rate of tooth movement and elucidates the deficiencies in the clinical studies that have been conducted so far to evaluate the effectiveness of these agents in humans, providing some guidelines for future robust research. Trial registration PROSPERO (CRD42020168481, www.crd.york.ac.uk/prospero)

Although my technical work and STS research may not be distinctly correlated, I believe that there are elements in both that can be attributed to a pursuing of how the medical engineering realm interacts with vulnerable populations. They have allowed me to explore how the way medical technology is designed can have a profound impact on the user. However, the medical technology realm is expansive with many different stages, thus I was able to study different areas in the two works. My technical work focuses on how an online cognitive bias modification program can most optimally engage and retain anxious patients, whereas my research explores how the conditions and approach of a medical trial effect how the technology can be developed at the expense of patients. Thus, by working on both projects has allowed me to think critically about how the technology that engineers output profoundly affects people. My technical work comprises of the designing of a mobile application for the interdisciplinary Mindtrails Calm study, an online anxiety research platform. The program, which evaluates cognitive bias modification for the purpose of reframing the patterns of highly anxious individuals, has faced high attrition rates. My Capstone project aimed to improve engagement and retention through the strategic implementation of personalization of training content, and the integration of implementation intentions and goal setting. We designed a prototype for a mobile interface that enables users to choose domains of anxiety to focus on while leveraging a new journal component through which users can record implementation intentions and goal setting to increase engagement. We then ran tests with real Mindtrails study participants for their feedback on the platform for the purpose of future development My STS research is also focused on a study for the purpose of developing technology for patients. My research examines an example of medical misconduct and how biomedical scientists’ pursuit of technology to better society comes through detriment of patients by demonstrating a lack of virtues. Virtue ethics is a theory that indicates which good or desirable characteristics people should have or develop in order to be moral. Analyzing the nature of a person allows for raising the question of “how to live” rather than what they did wrong in specific circumstances. My claim asserts that the lack of three key virtues vital to the medical profession: justice, respect, and integrity, are necessary for innovation of medical technology to occur without the expense of removing humanity and ethics that surround the job of being a physician. The goal of my research is to raise questions as to what responsibility biomedical engineers bear through the pursuit of technology in the quickly evolving medical landscape. I think that while I initially may have struggled to see the connection in the two projects, becoming more educated in both subjects allowed me to have a comprehensive approach as they informed each other. While working on my STS research, I found myself constantly reminded of the skills and methodologies that I learned through the Mindtrails team, and how they contrasted steeply with the egregious details of my case. My technical project allowed me to experience designing and implementing a study with real life subjects in the medical (psychological) realm, so I was able to understand my STS research case that is based in the Puerto Rico Birth Control study. Likewise, by becoming familiar with the virtues that best elevate scientific work, I was able to use them in the process of designing the app and associated user study for the Mindtrails participants.

A high protein content combined with its enormous growth capacity make duckweed an interesting alternative protein source, but information about postprandial responses in humans is lacking. The present study aimed to assess the postprandial serum amino acid profile of Lemna minor in healthy adults in comparison with green peas. A secondary objective was to obtain insights regarding human safety. A total of twelve healthy volunteers participated in a randomised, cross-over trial. Subjects received two protein sources in randomised order with a 1-week washout period. After an overnight fast, subjects consumed L. minor or peas (equivalent to 20 g of protein). After a baseline sample, blood samples were taken 15, 30, 45, 60, 75, 90, 120, 150 and 180 min after consumption to assess amino acid, glucose and insulin levels. Heart rate, blood pressure and aural temperature were measured before and after consumption, and subjects reported on gastrointestinal discomfort for four subsequent days. Compared with green peas, significantly lower blood concentrations of amino acids from L. minor were observed, indicating lower digestibility. L. minor consumption resulted in lower plasma glucose and insulin levels compared with peas, probably due to different glucose content. There were no significant differences concerning the assessed health parameters or the number of gastrointestinal complaints, indicating that a single bolus of L. minor – grown under controlled conditions – did not induce acute adverse effects in humans. Further studies need to investigate effects of repeated L. minor intake and whether proteins purified from L. minor can be digested more easily.

The brain-gut axis allows bidirectional communication between the central nervous system (CNS) and the enteric nervous system (ENS), linking emotional and cognitive centers of the brain with peripheral intestinal functions. Recent experimental work suggests that the gut microbiota have an impact on the brain-gut axis. A group of experts convened by the International Scientific Association for Probiotics and Prebiotics (ISAPP) discussed the role of gut bacteria on brain functions and the implications for probiotic and prebiotic science. The experts reviewed and discussed current available data on the role of gut microbiota on epithelial cell function, gastrointestinal motility, visceral sensitivity, perception and behavior. Data, mostly gathered from animal studies, suggest interactions of gut microbiota not only with the enteric nervous system but also with the central nervous system via neural, neuroendocrine, neuroimmune and humoral links. Microbial colonization impacts mammalian brain development in early life and subsequent adult behavior. These findings provide novel insights for improved understanding of the potential role of gut microbial communities on psychological disorders, most particularly in the field of psychological comorbidities associated with functional bowel disorders like irritable bowel syndrome (IBS) and should present new opportunity for interventions with pro- and prebiotics.

Several epidemiological studies associated the consumption of wine with the reduction of the risk factors for cardiovascular disease and certain cancers, as well as for diabetes. These conditions are characterized by inflammatory mechanisms in addition to other biological mechanisms. Acute and chronic inflammation is mediated by a plethora of biomarkers production and pathway activation. Since the health promoting properties of wine in different pathological conditions may include the reduction of inflammation, the aim of this paper was to collect and review the in vitro, in vivo, and human studies performed to evaluate the effects of wine on different models of inflammation. Although great variability in wine intake, period of consumption, and content of phenolic compounds was observed, data from both human and animal studies showed a positive modulation of inflammatory biomarkers (cytokines, coagulation parameters) and oxidative stress (mainly malondialdehyde) involved in cardiovascular function. In addition, some convincing evidence was obtained in different models suggesting a positive modulation of risk factors for gastric and intestinal inflammation. Contradictory results were obtained for metabolic syndrome and type 2 diabetes. To date, no significant paper has been published in the area of immune function. Integrating in vivo data and in vitro studies, the NF-κB pathway has been identified as a critical target for the protective properties of a moderate wine consumption.

Immunotherapy aims to assist the natural immune system in achieving control over viral infection. Various immunotherapy formats have been evaluated in either therapy-naive or therapy-experienced HIV-infected patients over the last 20 years. These formats included non-antigen specific strategies such as cytokines that stimulate immunity or suppress the viral replication, as well as antibodies that block negative regulatory pathways. A number of HIV-specific therapeutic vaccinations have also been proposed, using in vivo injection of inactivated virus, plasmid DNA encoding HIV antigens, or recombinant viral vectors containing HIV genes. A specific format of therapeutic vaccines consists of ex vivo loading of autologous dendritic cells with one of the above mentioned antigenic formats or mRNA encoding HIV antigens. This review provides an extensive overview of the background and rationale of these different therapeutic attempts and discusses the results of trials in the SIV macaque model and in patients. To date success has been limited, which could be explained by insufficient quality or strength of the induced immune responses, incomplete coverage of HIV variability and/or inappropriate immune activation, with ensuing increased susceptibility of target cells. Future attempts at therapeutic vaccination should ideally be performed under the protection of highly active antiretroviral drugs in patients with a recovered immune system. Risks for immune escape should be limited by a better coverage of the HIV variability, using either conserved or mosaic sequences. Appropriate molecular adjuvants should be included to enhance the quality and strength of the responses, without inducing inappropriate immune activation. Finally, to achieve a long-lasting effect on viral control (i.e. a “functional cure”) it is likely that these immune interventions should be combined with anti-latency drugs and/or gene therapy.

1. Barrier effect. Relevant models should include an anaerobic dominant flora that antagonizes minor bacterial populations such as drug resistant E. coli. 2. Anaerobes vs. aerobes. Aerobe counts are more precise and much less time consuming than anaerobe counts. Minor populations of drug resistant aerobes are sensitive markers of the ecosystem balance, and are directly relevant to the potential risk of antimicrobial residues. 3. MIC vs. plate counts. The determination of minimum inhibitory concentrations ( MIC ) of selected clones is time consuming, does not detect subdominant resistance (less than 1 %), and the MIC shift is difficult to test statistically. In contrast, direct counts of bacteria on drug supplemented media allows a rapid measure of minor resistant populations. 4. Statistics: Most published designs do not include adequate statistical evaluation. This is critical for trials made in conventional humans and animals, where data are highly variable. 5. Human trials: The lowest concentration of antibiotic tested in human volunteers (2mg oxytetracycline /d for 7d in 6 subjects) significantly increased the proportion of resistant fecal enterobacteria (P=0.05). However, the huge day-to-day and inter-individual variations of human floras make this evidence rather weak. 6. Gnotobiotic mice inoculated with human flora are living isolated models in which the effect of any antimicrobial on the human gut flora can be tested. This in vivo model does include the barrier effect of dominant anaerobes. Inter-individual and day-to-day variations of bacterial populations are lower in those mice than in humans. 7. Most resistant enterobacteria in the human gut of untreated people come from bacterial contamination of raw foods. The relative contribution of residues in selecting antibiotic resistance seems to be low when compared to bacterial contamination.