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Reintroduction of native freshwater mussels following aquatic habitat restoration is an increasingly used conservation practice to establish self-sustaining populations. Despite the common use of hatchery-grown subadult mussels (< 40 mm) for reintroduction efforts, their physical habitat requirements as well as guidance on identifying suitable release locations for different mussel species and sizes are severely lacking. We addressed this knowledge gap by deploying three-dimensional (3D)-printed subadult mussels equipped with scannable tags in a river as a proxy for hard-to-track live subadult mussels. We tracked mobilization, displacement and resettlement of 3D-printed and live freshwater mussels at five sites in the Mission Reach of the San Antonio River, Texas, USA, over two years. We found mobilization increased at higher discharges, smaller mussels mobilized at lower flows than adult mussels, site-specific geomorphic features reduced displacement distances, and boulder fields, or habitats with large stable roughness elements, resettled mussels at the highest rate. The study methods and results can directly inform freshwater mussel reintroduction efforts and river restoration project designs that include mussel habitats.

The Lower Cretaceous Viking Formation is a siliciclastic unit that occurs in the subsurface of Alberta in the Western Canadian sedimentary basin. This study focuses on a lowstand paleoshoreline trend extending along strike between two hydrocarbon-producing fields, Joarcam and Judy Creek (250 km NW). The Viking Formation in these fields records depositional thicknesses ranging from 20 to 30 m. Between these two fields, however, the formation is anomalously thick (45-60 m), complicating the recognition and correlation of key stratigraphic surfaces. Marine flooding surfaces above and below the Viking Formation are routinely employed as stratigraphic datums in order to remove postdepositional deformation and facilitate the development of a sequence stratigraphic framework. However, as each successive surface is employed as the datum, the other flooding surfaces within the formation become distorted, resulting in unrealistic depositional geometries. These geometries are best explained to be the result of structural readjustments during Viking deposition. The Precambrian lithosphere of the Canadian Shield forms the Western Canadian sedimentary basin basement, with major structures previously mapped using gravity and magnetic anomaly studies. Locally, the increased accommodation observed within the Viking Formation of central Alberta is attributed to differential reactivation of the Paleoproterozoic Snowbird tectonic zone basement structures, which flank the areas of anomalously thick deposits and trend approximately normal to the regional strike of the Western Canadian sedimentary basin. The Snowbird tectonic zone faults are interpreted to have been reactivated during renewed tectonic loading in the southern Canadian Cordillera during Aptian-Albian time, causing subtle readjustments along basement faults that caused variable syndepositional subsidence. By selecting successive datums, the gross Viking interval can be recognized to have accumulated prior to, during, and following structural reactivation.

Fat embolism syndrome (FES) is defined as an uncommon life-threatening disease process consisting of pulmonary, central nervous system (CNS), and cutaneous manifestations. The pathophysiology of this secondary injury is poorly understood. In the setting of the multiply injured patient, the diagnosis of FES is difficult to ascertain. A case report of a posttraumatic death caused by acute dissemination of diffuse fat emboli to the brain and lungs in the absence of a right-to-left heart defect after femur fracture is presented. The transesophageal echo cardiogram with bubble study failed to demonstrate an intracardiac defect or AV malformation in the lung further supporting a biochemical process. The acute decompensation of the patient within 2 h of the injury would favor mechanical emboli. Supportive care continues to be the mainstay of treatment for FES. Cerebral fat embolism should be considered in traumatically injured patients with unexplained decline in their neurologic examination. Cerebral fat embolism may occur without an intracardiac shunt.

Introduction Here, we report the first series of patients with 1-year implantation of a novel, endoluminal, endoscopically delivered and retrieved gastro-duodeno-jejunal bypass sleeve (GJBS) (ValenTx, Inc. Carpinteria, CA, USA). In this report, we present the safety, feasibility of the device, weight loss, and changes in comorbidities. Methods and procedures A prospective, single-center, 12-month trial was designed. The patients are morbidly obese individuals who meet the NIH criteria for bariatric surgery. The GJBS is a 120-cm sleeve secured at the esophago-gastric junction with endoscopic and laparoscopic techniques that is designed to create an endoluminal gastro-duodeno-jejunal bypass. The device was implanted and, at the completion of the trial, retrieved with an endoscopic technique. The primary endpoints were safety and incidence of adverse events. The secondary outcomes included the percentage of excess weight loss (EWL) and changes in comorbidities, specifically glucose control, use of antihyperglycemics, and changes in hemoglobin A1C levels. Results From July 2009 until October 2009, 13 patients were prospectively enrolled for the 1-year trial. The study included five men and eight women with a mean preoperative BMI of 42 kg/m 2 . One patient was excluded, at the time of endoscopic evaluation, due to inflammation at the GE junction. Two additional patients required early explantation of the device, within the first 4 weeks, due to patient intolerance. Upon explant of the device, both patients’ symptoms improved. In the remaining ten patients, the device was implanted, left in situ for 12 months, and then retrieved endoscopically. Safe delivery of the cuff at the gastro-esophageal junction was seen in all ten patients whom had device implants, without complication. No esophageal leak was seen immediately post-procedure or during follow-up. The sleeve device was well tolerated within the bowel lumen during the 12-month study, specifically, no bowel erosions, ulceration, or pancreatitis was observed. All ten patients reached the 1-year mark. Of the ten, six had fully attached and functional devices throughout the follow-up, verified by endoscopy. The mean percentage EWL, at 1 year, in this group was 54 %. In the remaining four patients, partial cuff detachment was observed at follow-up endoscopy. The percentage EWL was lower in this group. Of the six patients that reached a year with a fully attached device, five were followed at an average of 14-months post-explant (26 months from the time of device implant). These five maintained an average percentage EWL of 30 % at the 14-month post-explant follow-up. Co-morbidites measured included diabetes mellitus, hypertension, hyperlipidemia, and use of antihyperglycemics. Each of the measured comorbidities showed improvement during the 12-month trial. Discussion The endoluminal, GJBS can be safely placed and retrieved. The short-term data show it is well tolerated with a good safety profile. It achieves excellent weight loss results with over 70 % of all comorbidities resolved or significantly improved.

The tissue polarity pathway is required for the establishment of epithelial polarity in a variety of vertebrate and invertebrate organs. Core tissue polarity proteins act in a dynamically regulated complex to direct the polarization of the Drosophila eye. We report the identification and characterization of bedraggled (bdg), a novel gene that regulates one output of the tissue polarity pathway—the establishment of the R3/R4 photoreceptor fates. bdg encodes a novel, putative transporter protein and interacts genetically with all of the core polarity genes to influence the specification of the R3 and R4 cell fates. Finally, bdg is required for both viability and the initial stages of imaginal disc development.

All transfer RNAs (tRNAs) are highly modified. Several modifications are found within the tRNA elbow, including the universally conserved 5-methyluridine (m5U) 54 and pseudouridine (Ψ) 55 modifications in the T arm and 7-methylguanosine (m7G) 46 in the tRNA variable loop, formed by the bacterial tRNA modifying enzymes TrmA, TruB, and TrmB, respectively. Despite conservation of these enzymes throughout all domains of life, they are not essential for bacterial growth in ideal conditions. The overall goals of this thesis were to investigate molecular determinants for tRNA modification by these enzymes in vitro and determine cellular roles for these modifications in vivo. Specific chapters address (I) the preferential tRNA modification status for modification by TrmA, TruB, and TrmB, (II) the mechanism of tRNA binding by TrmB, and (III) the cellular roles for TrmA and TruB. Taken together, these studies reveal the mechanistic basis for TrmA and TruB acting in the early stages of tRNA maturation and provide justification for using an unmodified tRNA substrate for the rapid-kinetic analysis of TrmB binding tRNA, which reveals that prior S-adenosylmethionine binding is necessary for stable and rapid tRNA binding by TrmB. Additionally, residues distant from the active site within TrmB were identified to contribute for tRNA binding. Finally, tRNA sequencing, proteomics, and biochemical studies uncover that TrmA and TruB fine-tune global tRNA function by enhancing further tRNA modification, aminoacylation, and protein translation. In summary, this thesis provides insight into the tRNA binding and modification activity of three highly conserved tRNA modifying enzymes and identifies cellular roles of TrmA and TruB for tRNA modification, folding and protein synthesis, thus explaining why these enzymes are so highly conserved. This research sets the stage for studying the mechanisms and functions of further tRNA modifying enzymes, in addition to modification enzymes that target other species of RNAs.

Among the large and diverse collection of tRNA modifications, 7-methylguanosine is frequently found in the tRNA variable loop at position 46. This modification is introduced by the TrmB enzyme, which is conserved in bacteria and eukaryotes. Complementing the report of various phenotypes for different organisms lacking TrmB homologs, we report here hydrogen peroxide sensitivity for the Escherichia coli ΔtrmB knockout strain. To gain insight into the molecular mechanism of tRNA binding by E. coli TrmB in real-time, we developed a new assay based on introducing a 4-thiouridine modification at position 8 of in vitro transcribed tRNAPhe enabling us to fluorescently labelled this unmodified tRNA. Using rapid kinetic stopped-flow measurements with this fluorescent tRNA, we examined the interaction of wild-type and single substitution variants of TrmB with tRNA. Our results reveal the role of SAM for rapid and stable tRNA binding, the rate-limiting nature of m7G46 catalysis for tRNA release, and the importance of residues R26, T127 and R155 across the entire surface of TrmB for tRNA binding. Competing Interest Statement The authors have declared no competing interest.

Background This report describes the authors’ experience with a unique endoluminal, endoscopically delivered and retrieved gastroduodenojejunal bypass sleeve, including short-term weight loss and changes in comorbidities. Methods A prospective, single-center trial was designed. The patients were morbidly obese individuals who met the National Institutes of Health criteria for bariatric surgery. The device used was a unique gastroduodenojejunal bypass sleeve secured at the esophagogastric junction with endoscopic and laparoscopic techniques and designed to create an endoluminal gastroduodenojejunal bypass. At completion of the trial, the device was explanted with endoscopic retrieval. The primary end points were safety and incidence of adverse events. The secondary outcomes included the percentage of excess weight loss and changes in comorbidities, specifically glucose control, use of antihyperglycemic medications, and changes in hemoglobin A1c levels. Results From July 2008 to February 2010, 24 patients were enrolled in the trial. The gastroduodenojejunal bypass sleeve was implanted, left in situ, and then retrieved. The 7 men and 17 women in the study had a mean preoperative body mass index of 42 kg/m 2 . The device was successfully delivered in 22 of the 24 patients (92%) and retrieved endoscopically from all 22 patients in whom it was implanted (100%). Two patients were excluded from the study preprocedurally. The one patient was excluded preoperatively due to noncompliance with the preoperative liquid diet. For the other excluded patient, the device was not attempted endoscopically due to significant inflammation at the gastroesophageal junction at the time of laparoscopic evaluation. Of the 22 patients who had the device implanted, 17 maintained it (77%) and completed the full 12-week trial. These patients had 39.7% excess weight loss at completion of the study. The primary reason for early explantation of the device was early postoperative dysphagia. The seven patients with preoperative diabetes mellitus all had normal blood glucose levels throughout the trial, and none required antihyperglycemic medications. All four patients with elevated hemoglobin A1c levels preoperatively showed improvement by the end of the trial. Conclusions This trial demonstrated that the endoluminal gastroduodenojejunal sleeve can achieve excellent weight loss at 12 weeks. No patient safety issues were encountered. Adverse effects were minimal and resolved at endoscopic device removal. Effective glycemic control was demonstrated through use of the device during the trial. Long-term results are needed.

All elongator tRNAs harbor 5-methyluridine 54 and pseudouridine 55 in the T arm, which are generated by the enzymes TrmA and TruB, respectively. Escherichia coli TrmA and TruB both act as tRNA chaperones, and strains lacking trmA or truB are outcompeted by wildtype. Here, we investigate how TrmA and TruB contribute to cellular fitness. Deletion of trmA and truB in E. coli causes a global decrease in aminoacylation and alters other tRNA modification such as acp3U47. Whereas overall protein synthesis is not affected in ΔtrmA and ΔtruB strains, the translation of a specific subset of codons is significantly impaired, and the expression of many specific proteins is translationally changed. In conclusion, we demonstrate that universal modifications of the tRNA T arm are critical for global tRNA function by enhancing tRNA maturation, tRNA aminoacylation, and translation, thereby improving cellular fitness and explaining trmA and truB conservation.Competing Interest StatementThe authors have declared no competing interest.

Patient online health searching is now commonplace, however, the accuracy of patient generated differentials for new symptoms and potential for patient anxiety are concerns. We aimed primarily to determine the accuracy of patient generated differentials for new symptoms with and without online searching, and secondarily, to evaluate the impact of searching on anxiety levels. In the waiting room prior to seeing a clinician, 300 patients with new symptoms were randomly assigned 1:1:1 to Google searching with health related features including a symptom search tool vs Google searching with health related features disabled vs no searching. Participants were 18 years or older and presenting to the emergency department of an urban academic medical center with new low-acuity symptoms that were not due to exacerbation of a chronic condition. Search groups received access on a tablet/smartphone to Google searching with or without health related features. Both search groups could access any websites; health related features led the patient to common diagnoses and physician-validated information. The primary outcome was accuracy of the patient generated differential assessed by matching at least two of the top three diagnoses on the clinician’s differential. A secondary outcome was anxiety by a visual analogue scale. Patients were a median of 33.1 (IQI 26.2–45.9) years old, 60% women, 63% black, 82% had a high school education or less, and 45.7% reported having performed an online search prior to presentation. Search group patients spent a median of 3.82 (2.53–5.72) minutes searching online. Similar proportions of patients in each group matched at least two of three clinician diagnoses: 27.0% and 28.3% for Google searching with and without health related features vs 23.8% in the no search group. Patients in the search groups had a similar odds of matching ≥2/3 diagnoses as the no search group [OR (95% CI): 1.23 (0.70–2.13), p  = 0.47]. Anxiety was unchanged with online searching. In conclusion, brief online searching in the waiting room did not improve accuracy of patient generated differential diagnoses for new symptoms. The absence of an increase in patient anxiety provides reassurance for subsequent work to refine and investigate online symptom search tools.