Thermal deflection in neutron scattering sample environments at Oak Ridge National Laboratory.

The neutron sources at Oak Ridge National Laboratory use a wide suite of sample environment equipment to deliver extreme conditions for a number of experiments. Much of this instrumentation focuses on extremes of temperature, such as cryostats, closed-cycle refrigerators in both low and high temperature configurations, and radiant heating furnaces. When the temperature is controlled across a large range, thermal deflection effects can notably move the sample and affect its alignment in the beam. Here, we combine these sample environments with neutron imaging and machine vision to determine the motion of a representative sample with respect to the neutron beam. We find vertical sample displacement on the order of 1-2 mm and horizontal displacement that varies from near-negligible to 1.2 mm. While these deflections are not relevant for some of the beamlines at the first target station at the spallation neutron source and the high flux isotope reactor, they will become critical for upcoming instrumentation at the second target station, as well as any instruments targeting sub-mm samples, as neutron sources and optics evolve to smaller and more focused beams. We discuss mitigation protocols and potential modifications to the environment to minimize the effect of misalignment due to thermal deflection.

Dual stressors of infection and warming can destabilize host microbiomes.

Climate change is causing extreme heating events and intensifying infectious disease outbreaks. Animals harbour microbial communities, which are vital for their survival and fitness under stressful conditions. Understanding how microbiome structures change in response to infection and warming may be important for forecasting host performance under global change. Here, we evaluated alterations in the microbiomes of several wild Caenorhabditis elegans isolates spanning a range of latitudes, upon warming temperatures and infection by the parasite Leucobacter musarum. Using 16S rRNA sequencing, we found that microbiome diversity decreased, and dispersion increased over time, with the former being more prominent in uninfected adults and the latter aggravated by infection. Infection reduced dominance of specific microbial taxa, and increased microbiome dispersion, indicating destabilizing effects on host microbial communities. Exposing infected hosts to warming did not have an additive destabilizing effect on their microbiomes. Moreover, warming during pre-adult development alleviated the destabilizing effects of infection on host microbiomes. These results revealed an opposing interaction between biotic and abiotic factors on microbiome structure. Lastly, we showed that increased microbiome dispersion might be associated with decreased variability in microbial species interaction strength. Overall, these findings improve our understanding of animal microbiome dynamics amidst concurrent climate change and epidemics. This article is part of the theme issue 'Sculpting the microbiome: how host factors determine and respond to microbial colonization'.

Fatal intracranial hemorrhage as the presenting sign of acute promyelocytic leukemia: A case report.

Intracranial hemorrhage (ICH) can be a devastating medical event with numerous potential etiologies. In young people under age 40, ruptured vascular malformation is the most common cause of ICH. Without critical review of imaging and laboratory findings and clinical suspicion beyond vascular malformation, alternative etiologies of hemorrhage may be overlooked in the younger age group. Here we present a case of a 22-year-old male presenting with large ICH originally thought secondary to ruptured vascular malformation. After careful review of all imaging and laboratory findings, the patient was found to have hemorrhage secondary to acute promyelocytic leukemia (APL). Though ICH proved fatal in this case, early treatment of acute leukemia with appropriate chemotherapeutic agents and correction of coagulopathy could be life saving for patients with less severe intracranial injury.

Perceptions of barriers and facilitators to engaging in implementation science: a qualitative study.

OBJECTIVE: Understanding barriers and facilitators to engaging with implementation science (IS) research can provide insight into how to improve efforts to encourage more researchers to participate in IS research. STUDY DESIGN: The study design used is a grounded theory qualitative study. METHODS: We conducted semistructured telephone interviews with 20 health researchers familiar with IS that both report engaging in IS research and those that do not. We explored perceptions of barriers and facilitators to engaging in IS research. Themes surrounding difficulties defining IS, lack of training availability, and obstacles to forming research partnerships were discussed as barriers to engaging IS research. Interview topics were informed by the result of an online survey of health researchers in the US. RESULTS: Themes surrounding difficulties defining IS, lack of training availability, and obstacles to forming research partnerships were discussed as barriers to engaging IS research. While accessible mentorship, exposure to formative experiences that develop interest in IS research and an increasing IS visibility were described as motivators for engaging in IS research. CONCLUSIONS: These results highlight the importance of mentorship and exposure to IS ideas in motivating engagement in IS research and the presence of training and methodological barriers to engagement. Future research should expand this line of inquiry to include the perspectives of more junior researchers and students to better reflect the current IS environment.

Cord injury after spinal anaesthesia in a patient with previously undiagnosed Klippel-Feil syndrome.

This report presents an obstetric patient with no significant past medical history who underwent spinal anaesthesia for a category-three caesarean section. On examination, she had asymmetrical scapular alignment and a mild scoliosis of the lumbar spine with no functional limitation. Postoperatively the patient developed neuropathic pain symptoms in the right leg which failed to resolve with conventional analgesia. Cervical and lumbar spine magnetic resonance imaging was performed resulting in a diagnosis of a low-lying tethered spinal cord terminating at the level of L5 and congenital fusion of the C7/T1 vertebrae. A tethered spinal cord is a rare condition, which in this case had been completely asymptomatic. However, we suggest that the patient displayed musculoskeletal signs not previously widely reported, which could have indicated the presence of a potential underlying neural tube defect. Based on the imaging findings and the presence of Sprengel's deformity, the patient was diagnosed with Klippel-Feil syndrome.

Intramuscular infiltration of a local anesthetic, lidocaine, does not result in adverse behavioural side effects in rainbow trout.

Fish are a useful animal model for research, but our improvement in some aspects of their welfare has not kept pace with their increased popularity for this use. For example, researchers rarely use analgesics. We evaluated the side effects of lidocaine, a local anesthetic widely used in human and veterinary medicine. We infiltrated lidocaine on each side of the dorsal fin (total 20 mg/kg) of young rainbow trout (15 fish per group) compared with infiltration with an equal volume of saline. We monitored behaviour of individual trout during the 4-hour trial. Food was presented 5 times during the trial (30 min, 1 h, 2 h, 3 h, 4 h after infiltration) and we analyzed behaviour for 1 minute before and after food presentation. Behaviour of Saline-Infiltrated trout compared with trout that received no infiltration showed that infiltration in and of itself had no statistically significant effects on trout behaviour. However, there were many statistically significant effects of Lidocaine-Infiltrated trout compared with Saline-Infiltrated trout; none of the side-effects were adverse.

Adherence of stroke patients with an online brain training program: the role of health professionals' support.

Background Computer-based cognitive rehabilitation is used to improve cognitive functioning after stroke. However, knowledge on adherence rates of stroke patients is limited. Objective To describe stroke patients' adherence with a brain training program using two frequencies of health professionals' supervision. Methods This study is part of a randomized controlled trial comparing the effect of the brain training program (600 min playtime with weekly supervision) with a passive intervention in patients with self-perceived cognitive impairments after stroke. Patients randomized to the control condition were offered the brain training after the trial and received supervision twice (vs weekly in intervention group). Adherence was determined using data from the study website. Logistic regression analyses were used to examine the impact of supervision on adherence. Results 53 patients allocated to the intervention group (group S8; 64% male, mean age 59) and 52 patients who were offered the intervention after the trial (group S2; 59% male, mean age 59) started the brain training. The median playtime was 562 min (range 63-1264) in group S8 vs. 193 min (range 27-2162) in group S2 (p < 0.001, Mann Whitney U). Conclusions The overall adherence of stroke patients with a brain training was low and there are some implications that systematic, regular interaction with a supervisor can increase training adherence of stroke patients with a restitution-focused intervention performed at home.

Updated Review of Fish Analgesia.

Analgesics are an integral part of routine pain management in mammals, yet their use in fish is still limited. Some recommendations on the use of analgesics in fish are currently in the literature; however, information on the properties of analgesic drugs in most fish species is still scarce and sometimes misleading. The present review of information on the use of analgesics in fish was thus compiled to help clinicians make an informed decision as to which drug and dose to use. The main agents that have been investigated are opioids, NSAID, and local anesthetics, primarily in rainbow trout and zebrafish. There is presently no overwhelming evidence of efficacy for most analgesics in fish, although beneficial effects on behavior and physiologic parameters have been reported in many instances, especially associated with morphine administration. Furthermore, most analgesics did not result in significant adverse side effects. Thus, analgesics could be administered whenever it is considered that an animal might experience pain, given that the drugs appear not to cause harm and may be beneficial. However, caution must be advised because 1) important interspecies variation has been reported and 2) unforeseen effects could affect experimental results. Further research is needed to investigate analgesic use in fish. This should be accompanied by research aimed at improving our knowledge of the various species of fish. The current lack of a validated approach to assessing pain in fish limits our ability to evaluate the efficacy of analgesics in fish.

Evaluation of tissue changes following intramuscular infiltration of lidocaine in rainbow trout Oncorhynchus mykiss.

Rainbow trout Oncorhynchus mykiss were infiltrated with either saline or lidocaine adjacent to the dorsal fin to assess histopathological changes. Infiltration was done as if it were being used as a local anaesthetic. Tissue lesions and associated tissue healing were examined over a period of 30 days. Most changes occurred at the cranial site of where the solution was first infiltrated. The infiltration of a dose of 10 mg kg-1 of lidocaine appears to have damaged the skeletal muscle and connective tissues more than a similar volume of saline, especially during the first 15 days. The primary changes included haemorrhage, inflammation and muscle degeneration and necrosis. By day 30 post-infiltration inflammatory lesions were either nearly or completely absent, signs of myofibre regeneration were noted in only one fish. This experiment shows local anaesthetics and saline can produce localized tissue damage, especially during the first 2 weeks post infiltration. Care should be taken to allow the fish to heal for at least 30 days and probably more, no matter the solution administered, especially if giving repeated injections or infiltrations at the same site.

Lack of postexposure analgesic efficacy of low concentrations of eugenol in zebrafish.

OBJECTIVE: To test the postexposure analgesic efficacy of low doses of eugenol in zebrafish. STUDY DESIGN: Prospective experimental study. ANIMALS: A total of 76 large adult zebrafish (Danio rerio). METHODS: Fish swimming behavior (median velocity, freeze time, high-speed swimming and distance moved in the vertical direction) was recorded in a 1.6 L video arena before and after exposure to eugenol (0, 1, 2, 5, 10 and 20 mg L-1). In a second experiment, fish were anesthetized with 2-phenoxy-ethanol and treated with an injection of 5% acetic acid (noxious stimulus), and then exposed to 0, 1, 2 and 5 mg L-1 eugenol. The fish swimming behavior was also recorded. RESULTS: The higher doses (10 and 20 mg L-1) reduced the median velocity, high-speed swimming and distance moved in the vertical direction, and increased the freeze time. Zebrafish behavior was not altered by eugenol (1, 2 and 5 mg L-1) after noxious stimulation. CONCLUSIONS AND CLINICAL RELEVANCE: The change in the behavior of zebrafish associated with a noxious stimulus can be monitored and is a good model for studying analgesia in fish. Eugenol (10 and 20 mg L-1) induced zebrafish sedation. The response after a noxious stimulus was not affected by postexposure to lower doses, and thus we cannot recommend its use as an analgesic.

Uses and Doses of Local Anesthetics in Fish, Amphibians, and Reptiles.

Local anesthetics are an integral part of routine pain management in mammals, yet their use is relatively limited in fish, amphibians and reptiles. These animals frequently undergo potentially painful surgical procedures and therefore could possibly benefit from those drugs. Some recommendations are currently available in the literature concerning analgesic use in these animals. However the pharmacological properties, safety and often efficacy of local anesthetic drugs have not been investigated yet in fish, amphibians, or reptiles. This review compiled current information concerning the use of those agents in fish, reptiles and amphibians to help clinicians make an informed decision as to which dose and drug to use. The resulting literature search showed that the literature concerning use of local analgesics in fish and amphibians is very limited while the literature for reptiles is more extensive. We found few experimental studies evaluating the efficacy of local anesthetics. Further studies would provide additional information for developing guidelines to improve the welfare of fish, amphibians and reptiles.

Barite encrustation of benthic sulfur-oxidizing bacteria at a marine cold seep.

Crusts and chimneys composed of authigenic barite are found at methane seeps and hydrothermal vents that expel fluids rich in barium. Microbial processes have not previously been associated with barite precipitation in marine cold seep settings. Here, we report on the precipitation of barite on filaments of sulfide-oxidizing bacteria at a brine seep in the Gulf of Mexico. Barite-mineralized bacterial filaments in the interiors of authigenic barite crusts resemble filamentous sulfide-oxidizing bacteria of the genus Beggiatoa. Clone library and iTag amplicon sequencing of the 16S rRNA gene show that the barite crusts that host these filaments also preserve DNA of Candidatus Maribeggiatoa, as well as sulfate-reducing bacteria. Isotopic analyses show that the sulfur and oxygen isotope compositions of barite have lower δ(34)S and δ(18)O values than many other marine barite crusts, which is consistent with barite precipitation in an environment in which sulfide oxidation was occurring. Laboratory experiments employing isolates of sulfide-oxidizing bacteria from Gulf of Mexico seep sediments showed that under low sulfate conditions, such as those encountered in brine fluids, sulfate generated by sulfide-oxidizing bacteria fosters rapid barite precipitation localized on cell biomass, leading to the encrustation of bacteria in a manner reminiscent of our observations of barite-mineralized Beggiatoa in the Gulf of Mexico. The precipitation of barite directly on filaments of sulfide-oxidizing bacteria, and not on other benthic substrates, suggests that sulfide oxidation plays a role in barite formation at certain marine brine seeps where sulfide is oxidized to sulfate in contact with barium-rich fluids, either prior to, or during, the mixing of those fluids with sulfate-containing seawater in the vicinity of the sediment/water interface. As with many other geochemical interfaces that foster mineral precipitation, both biological and abiological processes likely contribute to the precipitation of barite at marine brine seeps such as the one studied here.

Tumors in the parotid are not relatively more often malignant in children than in adults.

INTRODUCTION: Tumors of the parotid gland in children are rare and very little data has been published regarding the incidence of these tumors. We present a nationwide survey on this topic. METHODS: Data regarding benign and malignant tumors in the parotid gland in children from January 1st, 1990 to December 31st, 2005 in Denmark was collected retrospectively from nationwide registries. This generated 61 patients for inclusion in this study. RESULTS: 85% of the tumors were benign and the malignant tumors made up the last 15%. The most common of the malignant tumors was the acinic cell carcinoma (n=4) followed by the mucoepidermoid carcinoma (n=3) and adenoid cystic carcinoma (n=2). The overall female-to-male ratio was 1.18, with a ratio of 1.08 and 2.0 in the benign and malignant groups, respectively. At the end of follow-up (August 1st, 2014) two patients had died, one with adenoid cystic carcinoma and one with mucoepidermoid carcinoma. Both patients had perineural invasion and involved resection margins at presentation. The incidence was 0.12 and 0.53 per 100,000 children of the malignant and benign tumors, respectively. CONCLUSION: Pleomorphic adenomas were the predominant neoplasm in the parotid gland in children. The most frequent of the malignant tumors was the acinic cell carcinoma, which is in contrast to previous studies. The proportion of malignant-to-benign parotid gland tumors is in contrast to earlier study reports not higher in children than in adults.

Increased brain response to appetitive tastes in the insula and amygdala in obese compared with healthy weight children when sated.

OBJECTIVE: There is evidence of altered neural taste response in female adolescents who are obese (OB), and in adolescents who are at risk for obesity. To further understand risk factors for the development of overeating and obesity, we investigated response to tastes of sucrose and water in 23 OB and healthy weight (HW) children. METHODS AND DESIGN: Thirteen HW and 10 OB 8-12-year-old children underwent functional magnetic resonance imaging while tasting sucrose and water. Additionally, children completed an eating in the absence of hunger paradigm and a sucrose-liking task. RESULTS: A region of interest analysis revealed an elevated BOLD response to taste (sucrose and water) within the bilateral insula and amygdala in OB children relative to HW children. Whole-brain analyses revealed a group by condition interaction within the paracingulate, medial frontal, middle frontal gyri and right amygdala: post hoc analyses suggested an increased response to sucrose for OB relative to HW children, whereas HW children responded more strongly to water relative to sucrose. In addition, OB children, relative to HW, tended to recruit the right putamen as well as medial and lateral frontal and temporal regions bilaterally. CONCLUSION: This study showed increased reactivity in the amygdala and insula in the OB compared with HW children, but no functional differentiation in the striatum, despite differences in the striatum previously seen in older samples. These findings support the concept of the association between increased neural processing of food reward in the development of obesity, and raise the possibility that emotional and interoceptive sensitivity could be an early vulnerability in obesity.

Effect of TRIS and bicarbonate as buffers on anesthetic efficacy of tricaine methane sulfonate in Zebrafish (Danio rerio).

Tricaine methane sulfonate (TMS), often called MS-222, is the most common anesthetic used with fishes. Because it is very acidic (pKa about 3) it must be neutralized especially when used in soft fresh water. Much of the literature on fish anesthetics recommends neutralizing with bicarbonate. However, much of the zebrafish literature uses the protocol in "The Zebrafish Book" that recommends neutralizing with TRIS. Three considerations when comparing these buffers are: first, TRIS has the advantage that the pH tends to remain constant, whereas the pH of solutions containing bicarbonate tends to increase as CO2 diffuses from the water to air; second, the CO2 produced by bicarbonate may have some sedative effects in and of itself; and third, there is some evidence that the efficacy of TMS changes with pH. In the present study, we compared the efficacy of TMS using these two buffers and show that there is no substantial difference in anesthetic properties in zebrafish.

Preliminary results from a prospective study of laparoscopic aortobifemoral bypass using a clampless and sutureless aortic anastomotic technique.

OBJECTIVE: This prospective study describes the feasibility and safety of a new clampless and sutureless aortic anastomotic technique used during retroperitoneal laparoscopic aortobifemoral bypass in extensive aortoiliac occlusive lesions. This is a case series of a previously published technique, demonstrating wider applicability of the technique. MATERIALS AND METHODS: Twelve patients underwent a clampless and sutureless laparoscopic bypass for TASC D aortoiliac occlusive lesions using the EndoVascular REtroperitoneoScopic Technique (EVREST). Dissection of the retroperitoneal space and the infrarenal aorta was performed laparoscopically. A bifurcated graft was inserted into the retroperitoneal space. The main body of the graft was connected on the left side of the aorta by an intra- and extra-aortic covered stent-graft. An aortic clamp was used temporarily on four patients because of excessive bleeding when the connector was deployed. The femoral anastomoses were performed by classic open surgery. Initial technical success, complications, and bypass patency were assessed. RESULTS: Median follow-up was 9.3 months. Median operative time was 265 minutes. Median duration of aorto-prosthetic connection was 60 seconds. Thirty-day postoperative mortality was 0%. No major postoperative complications were observed. All grafts were patent at the end of follow-up and there was no early or late disruption of the proximal assembly. CONCLUSIONS: EVREST greatly facilitates laparoscopic aortic surgery in occlusive disease with no need for suture or clamping of the aorta. This technique performed in a single center on 12 patients, seems to be feasible and safe. It offers the advantages of laparoscopy and those of endovascular surgery, especially in the challenging conditions encountered during aortic laparoscopic surgery. Early experience supports procedural and initial postprocedural safety and demonstrates proof-of-concept for EVREST.