RNA Editing at Baseline and Following Endoplasmic Reticulum Stress.

RNA sequences are expected to be identical to the DNA template. However, some RNA processing steps, such as RNA editing, can lead to differences in the RNA sequence that affect the fate of the RNA transcripts or the resultant proteins. My thesis focuses on the regulation of the canonical A-to-G editing and non-canonical RNA-DNA sequence Differences (RDD). My work contributed to the identification of RDDs throughout the human transcriptome. We identified all 12 types of single base differences across multiple individuals and various tissue types. We also detected peptides matching the RDD-encoded sequences suggesting that RDDs are translated into proteins. In subsequent work, we found that the non-canonical RDDs are found in nascent RNA. Through the use of nuclear run-on assays, we found that RDD occurs within seconds of exiting the RNA polymerase complex. Chapters 4 and 5 discuss my study of canonical A-to-G editing mediated by Adenosine Deaminase Acting on RNA (ADAR). First, we found that A-to-G editing levels differ across individuals. I searched for and identified genetic variants whose alleles are associated with editing levels of sites in the same gene. These data demonstrate that ADAR editing is cis regulated and can lead to individual variability in editing levels. Furthermore, by utilizing individual variability in editing and studying the relationship between editing sites, I learned how ADAR edits multiple sites in a given transcript. My data support a model where ADAR edits multiple sites along one side of a double-stranded RNA structure. To learn about the biological significance of RNA editing, I focused on endoplasmic reticulum (ER) stress. I found that editing levels change following ER stress suggesting that these RNA processing steps play a role in the ER stress response. Together, this work sheds light on the regulation of RNA editing and RDDs in the human transcriptome and aids in the understanding of how these processes may play a role in cellular response to stress.PhDHuman GeneticsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/116721/1/allirich_1.pd

Incidence, time course and predictors of impairments relating to caring for the profoundly affected arm after stroke: A systematic review

Background and purpose - A significant number of stroke survivors will not recover the use of their affected arm. A proportion will experience pain, stiffness and difficulty with basic care activities. The purpose of the review was to identify predictors of difficulty caring for the profoundly affected arm and establish the incidence and time-course of the related impairments of pain, spasticity and contracture. Method - Data sources: Databases (PubMED, MEDLINE, AMED, EMBASE, CINAHL and the Cochrane Controlled Trials Register) were searched from inception to December 2013. Additional studies were identified from citation tracking. Review methods: Independent reviewers used pre-defined criteria to identify eligible studies. Quality assessment and risk of bias were assessed using the McMasters Assessment Tool. A narrative evidence synthesis was performed. Results - Thirty-nine articles reporting 34 studies were included. No studies formally measured difficulty caring for the arm, but related impairments were common. Incidence of spasticity in those with weakness ranged from 33% to 78%, shoulder pain affected 22% to 90% and contracture was present in at least 50%. Spasticity and pain appear within 1 week of stroke, and contracture within two weeks. Impairments continued to develop over at least 3–6 months. The most frequent predictors of spasticity and contracture were weakness and reduced motor control, and the risk of pain is most commonly predicted by reduced sensation, shoulder subluxation, weakness and stroke severity. Discussion - There is no published evidence on predicting the likelihood of difficulty caring for the arm following stroke. However, the related impairments of spasticity, pain and contracture are common. Given the time-course of development, clinicians may need not only to intervene early but also be prepared to act over a longer time period. Further research is needed to examine difficulty caring for the arm and the relationship with associated impairments to enable researchers and clinicians to develop targeted interventions

Assay validation and interspecific comparison of salivary glucocorticoids in three amphibian species

Amphibians are one of the most threatened groups of species, facing stressors ranging from habitat degradation and pollution to disease and overexploitation. Stress hormones (glucocorticoids, GCs) provide one quantitative metric of stress,and developing non-invasive methods for measuring GCs in amphibians would clarify how diverse environmental stressors impact individual health in this taxonomic group. Saliva is an advantageous matrix for quantifying GCs, as it is sampled less invasively than plasma while still detecting both baseline and acute elevation of GCs within a short timeframe. Little work has employed this method in amphibian species, and it has never been pharmacologically and biologically validated. Here, we conduct analytical, pharmacological and biological validation experiments for measuring salivary corticosterone in three amphibian species: the American bullfrog (Rana catesbeiana), the green frog (Rana clamitans) and the northern leopard frog (Rana pipiens). These species are faced with a broad range of environmental challenges, and in part of its range R. pipiens populations are currently in decline. In addition to demonstrating that this method can be reliably used in multiple amphibian species, we present an examination of intrinsic biological factors (sex, body condition) that may contribute to GC secretion, and a demonstration that saliva can be collected from free-living animals in the field to quantify corticosterone. Our findings suggest that saliva may be useful for less invasively quantifying GCs in many amphibian species

Sailing across the North Sea:The development of trust in a short-term high intensity environment

Interpersonal trust among team members is an important phenomenon influencing working relationships and performance outcomes. However, there is a lack of empirical studies investigating the development of trust with respect to behavioural and environmental factors in a group of strangers. This exploratory, mixed method study investigated the development of two-dimensional interpersonal trust (affective and cognitive) and team cohesion in a newly formed temporary team of novice adults during a seven-day sail training programme. A descriptive longitudinal case study approach was adopted in the current study. Seven crew members completed the standardised psychometric questionnaires and were interviewed during the voyage. Results suggested that the development of trust occurs over three phases; 1) initial perception of shared identity, 2) early trust and 3) two dimensional trust comprising cognitive and affective dimensions. Distinct antecedents for the development of trust at each stage were identified and the importance of the competence-oriented subcomponent of cognitive trust within this challenging environmental context was highlighted. Exploratory interpretation suggests some overlap in the antecedents of interpersonal trust and team cohesion. However, further longitudinal research must examine this relationship and establish corroborative evidence for the model of trust. This research can impact on practitioners leading programmes to better understand how trust can develop over time, and offers a pragmatic approach to investigations in real world contexts

Anticancer metallohelices: nanomolar potency and high selectivity

A range of new helicate-like architectures have been prepared via highly diastereoselective self-assembly using readily accessible starting materials. Six pairs of enantiomers [Fe2L3]Cl4.nH2O (L = various bidentate ditopic ligands NN–NN) show very good water solubility and stability. Their activity against a range of cancer cell lines in vitro is structure-dependent and gives IC50 values as low as 40 nM. In an isogenic pair of HCT116 colorectal cancer cells, preferential activity was observed against cell lines that lack functional p53. Selectivity is also excellent, and against healthy human retinal pigment epithelial (ARPE19) and lung fibroblast (WI38) cells IC50 values are nearly three orders of magnitude higher. Cisplatin is unselective in the same tests. The compounds also appear to have low general toxicity in a number of models: there is little if any antimicrobial activity against Methicillin-resistant Staphylococcus aureus and Escherichia coli.; Acanthamoeba polyphaga is unaffected at 25 μg ml-1 (12.5 μM); Manduca sexta larvae showed clear evidence of systemic distribution of the drug, and rather than any observation of adverse effects they exhibited a significant mean weight gain vs controls. Investigation of the mode of action revealed no significant interaction of the molecules with DNA, and stimulation of substantial cell death by apoptosis

Accuracy and Consistency of Radiographic Interpretation Among Clinical Instructors Using Two Viewing Systems

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153540/1/jddj002203372006702tb04071x.pd

Accuracy and Consistency of Radiographic Interpretation Among Clinical Instructors Using Two Viewing Systems

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153540/1/jddj002203372006702tb04071x.pd

AGN Populations in Large Volume X-ray Surveys: Photometric Redshifts and Population Types found in the Stripe 82X Survey

Multi-wavelength surveys covering large sky volumes are necessary to obtain an accurate census of rare objects such as high luminosity and/or high redshift active galactic nuclei (AGN). Stripe 82X is a 31.3 deg$^2$ X-ray survey with $Chandra$ and $XMM$-Newton observations overlapping the legacy Sloan Digital Sky Survey (SDSS) Stripe 82 field, which has a rich investment of multi-wavelength coverage from the ultraviolet to the radio. The wide-area nature of this survey presents new challenges for photometric redshifts for AGN compared to previous work on narrow-deep fields because it probes different populations of objects that need to be identified and represented in the library of templates. Here we present an updated X-ray plus multi-wavelength matched catalog, including $Spitzer$ counterparts, and estimated photometric redshifts for 5961 (96% of a total of 6181) X-ray sources, which have a normalized median absolute deviation, $\sigma_{\rm nmad}$ = 0.06 and an outlier fraction, $\eta$ = 13.7%. The populations found in this survey, and the template libraries used for photometric redshifts, provide important guiding principles for upcoming large-area surveys such as $eROSITA$ and 3$XMM$ (in X-ray) and the Large Synoptic Survey Telescope (LSST; optical).Comment: Accepted for publication by The Astrophysical Journal (33 pages, 20 figures, 13 tables). Final catalog of counterparts and photo-z supplementing the paper available here: http://stripe82x.com/docs/stripe82x-photometric-redshifts-and-multiwavelength-data-catalog

Maternal steroid levels and the autistic traits of the mother and infant.

BackgroundPrenatal sex steroids have been associated with autism in several clinical and epidemiological studies. It is unclear how this relates to the autistic traits of the mother and how early this can be detected during pregnancy and postnatal development.MethodsMaternal serum was collected from pregnant women (n = 122) before or during their first ultrasound appointment [mean = 12.7 (SD = 0.7) weeks]. Concentrations of the following were measured via immunoassays: testosterone, estradiol, dehydroepiandrosterone sulphate, progesterone; and sex hormone-binding globulin which was used to compute the free fractions of estradiol (FEI) and testosterone (FTI). Standardised human choriogonadotropin (hCG) and pregnancy-associated plasma protein A (PAPP-A) values were obtained from clinical records corresponding to the same serum samples. Mothers completed the Autism Spectrum Quotient (AQ) and for their infants, the Quantitative Checklist for Autism in Toddlers (Q-CHAT) when the infants were between 18 and 20 months old.ResultsFEI was positively associated with maternal autistic traits in univariate (n = 108, Pearson's r = 0.22, p = 0.019) and multiple regression models (semipartial r = 0.19, p = 0.048) controlling for maternal age and a diagnosis of PCOS. Maternal estradiol levels significantly interacted with fetal sex in predicting infant Q-CHAT scores, with a positive relationship in males but not females (n = 100, interaction term: semipartial r = 0.23, p = 0.036) after controlling for maternal AQ and other covariates. The opposite was found for standardised hCG values and Q-CHAT scores, with a positive association in females but not in males (n = 151, interaction term: r = -0.25, p = 0.005).LimitationsSample size of this cohort was small, with potential ascertainment bias given elective recruitment. Clinical covariates were controlled in multiple regression models, but additional research is needed to confirm the statistically significant findings in larger cohorts.ConclusionMaternal steroid factors during pregnancy are associated with autistic traits in mothers and their infants