Mapping and comparing fMRI connectivity networks across species.

Technical advances in neuroimaging, notably in fMRI, have allowed distributed patterns of functional connectivity to be mapped in the human brain with increasing spatiotemporal resolution. Recent years have seen a growing interest in extending this approach to rodents and non-human primates to understand the mechanism of fMRI connectivity and complement human investigations of the functional connectome. Here, we discuss current challenges and opportunities of fMRI connectivity mapping across species. We underscore the critical importance of physiologically decoding neuroimaging measures of brain (dys)connectivity via multiscale mechanistic investigations in animals. We next highlight a set of general principles governing the organization of mammalian connectivity networks across species. These include the presence of evolutionarily conserved network systems, a dominant cortical axis of functional connectivity, and a common repertoire of topographically conserved fMRI spatiotemporal modes. We finally describe emerging approaches allowing comparisons and extrapolations of fMRI connectivity findings across species. As neuroscientists gain access to increasingly sophisticated perturbational, computational and recording tools, cross-species fMRI offers novel opportunities to investigate the large-scale organization of the mammalian brain in health and disease.

Exercise promotes growth and rescues volume deficits in the hippocampus after cranial radiation in young mice.

Human and animal studies suggest that exercise promotes healthy brain development and function, including promoting hippocampal growth. Childhood cancer survivors that have received cranial radiotherapy exhibit hippocampal volume deficits and are at risk of impaired cognitive function, thus they may benefit from regular exercise. While morphological changes induced by exercise have been characterized using magnetic resonance imaging (MRI) in humans and animal models, evaluation of changes across the brain through development and following cranial radiation is lacking. In this study, we used high-resolution longitudinal MRI through development to evaluate the effects of exercise in a pediatric mouse model of cranial radiation. Female mice received whole-brain radiation (7 Gy) or sham radiation (0 Gy) at an infant equivalent age (P16). One week after irradiation, mice were housed in either a regular cage or a cage equipped with a running wheel. In vivo MRI was performed prior to irradiation, and at three subsequent timepoints to evaluate the effects of radiation and exercise. We used a linear mixed-effects model to assess volumetric and cortical thickness changes. Exercise caused substantial increases in the volumes of certain brain regions, notably the hippocampus in both irradiated and nonirradiated mice. Volume increases exceeded the deficits induced by cranial irradiation. The effect of exercise and irradiation on subregional hippocampal volumes was also characterized. In addition, we characterized cortical thickness changes across development and found that it peaked between P23 and P43, depending on the region. Exercise also induced regional alterations in cortical thickness after 3 weeks of voluntary exercise, while irradiation did not substantially alter cortical thickness. Our results show that exercise has the potential to alter neuroanatomical outcomes in both irradiated and nonirradiated mice. This supports ongoing research exploring exercise as a strategy for improving neurocognitive development for children, particularly those treated with cranial radiotherapy.

Does the flamenco tourist exist? Motivation and segmentation.

Flamenco is a popular art, symbol of the culture of southern Spain, has a growing number of fans both from this country and from the rest of the world. This paper tried to find out if flamenco can be a determinant motivational element when choosing a destination and if there is a specific flamenco tourist who tries to travel to symbolic flamenco places. The results show evidence of the existence of three motivational dimensions directly related to flamenco: flamenco experience, flamenco brand, flamenco pretext. Also, a so-called 'musical dimension' was observed, where the motivation to participate in musical experiences in general prevailed. Based on these motivational dimensions, three types of flamenco tourists were identified: flamenco lovers, friends of flamenco, and musical attraction. It was found that the group formed by 'flamenco lovers' has a very high sensitivity to all musical variables related to flamenco, being this one, the most numerous group.

Impact of implant thread design on insertion torque and osseointegration: a preclinical model.

BACKGROUND: Successful osseointegration of endosteal dental implants has been attributed to implant design, including the macro-, micro- and nano- geometric properties. Based on current literature pertaining to implant design, the resultant cellular and bone healing response is unknown when the thread thickness of the implants is increased, resulting in an increased contact area in implants designed with healing chambers. The aim of this study was to evaluate the effect of two implant designs with different thread profiles on the osseointegration parameters and implant stability at 3- and 6-weeks in vivo using a well-established preclinical dog model. MATERIAL AND METHODS: A total of 48 type V Ti alloy implants were divided in two groups according to their thread design (D1= +0.1x/mm and D2= +0.15x/mm) and placed in an interpolated fashion into the radii of six beagles. Insertion torque was measured at time of placement, radii were extracted for histological processing following 3- and 6-week healing intervals. Histologic and histomorphometric analyses were performed in terms of bone to implant contact (%BIC) and bone area fraction occupancy within implant threads (%BAFO). Statistical analyses were performed through a linear mixed model with fixed factors of time and implant thread design. RESULTS: Surface roughness analysis demonstrated no significant differences in Sa and Sq between D1 and D2 implant designs, which confirmed that both implant designs were homogenous except for their respective thread profiles. For insertion torque, statistically significant lower values were recorded for D1 in comparison to D2 (59.6 ± 11.1 and 78.9 ± 10.1 N⋅cm, respectively). Furthermore, there were no significant differences with respect to histological analysis and histomorphometric parameters, between D1 and D2 at both time points. CONCLUSIONS: Both thread profiles presented equivalent potential to successfully osseointegrate in the osteotomies, with D2 yielding higher mechanical retention upon placement without detrimental bone resorption.

Evaluación funcional con la escala KSS (Knee Society Score) a tres y seis meses de la reconstrucción ligamentaria en pacientes con lesiones multiligamentarias de rodilla en un hospital de tercer nivel / Functional evaluation with the KSS (Knee Society Score) scale at 3 and 6 months after ligament reconstruction in patients with multi-ligament knee injuries in a third level hospital

Resumen: Las lesiones multiligamentarias de la articulación de la rodilla se caracterizan por la afección de dos o más ligamentos principales, ligamento cruzado anterior (LCA), ligamento cruzado posterior (LCP), ligamento colateral medial (LCM), ligamento colateral lateral (LCL), esquina posteromedial (EPM) y esquina posterolateral (EPL). Estadísticamente, las lesiones multiligamentarias son poco frecuentes, ya que se encuentran en menos de 0.02% de todas las lesiones traumáticas de rodilla; sin embargo, diferentes lesiones agregadas son las que hacen de esta patología un estado grave para salud y funcionalidad. Tomando en cuenta que la mayoría de los pacientes son personas jóvenes en edad altamente productiva, es de vital importancia observar la evolución de los mismos a corto y largo plazo, así como su reincorporación a su vida cotidiana. Se ha descrito que las lesiones vasculares se presentan aproximadamente en 32% de los casos, lesiones meniscales en 35% y hasta 60% con algún tipo de lesión ósea. Estas lesiones afectan principalmente al sexo masculino con más frecuencia entre la tercera y cuarta década de la vida, lo cual hace a este tipo de lesiones de gran importancia, ya que este grupo de pacientes se encuentran en su mayor período de producción laboral. El objetivo principal del tratamiento de estas lesiones, además de resolver los daños agregados que suelen ser los agravantes del estado de salud, es lograr una pronta recuperación y posterior reincorporación a sus actividades laborales y en algunos casos deportivas.

Abstract: Multiligament injuries of the knee joint are characterized by the involvement of two or more major ligaments, anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), lateral collateral ligament (LCL), posteromedial corner (PMC) and posterolateral corner (PLC). Statistically, multiligament injuries are rare as they are found in less than 0.02% of all traumatic knee injuries; however, different aggregate injuries are what make this pathology a serious health and functional condition. Taking into account that most of the patients are young people of highly productive age, it is of vital importance to observe their short and long term evolution, as well as their reincorporation to their daily life. It has been reported that vascular lesions are present in approximately 32% of cases, meniscal lesions in 35% and up to 60% with some type of bone lesion. These injuries mainly affect the male sex most commonly between the third and fourth decade of life, which makes this type of injury of great importance, since this group of patients are in their greatest period of labor production. The main objective of the treatment of these injuries, in addition to resolving the aggregate damage that usually aggravates the state of health, is to achieve a speedy recovery and subsequent reincorporation to their work activities and in some cases sports.

Percutaneous closure of a ruptured right coronary sinus of Valsalva aneurysm that mimics severe aortic regurgitation.

A 34-year-old male was admitted with presumed acute, severe aortic regurgitation. Multimodal imaging was performed and showed a ruptured right coronary sinus of Valsalva aneurysm into the right atrium. He underwent a percutaneous closure of the ruptured sinus of Valsalva aneurysm. The patient had major clinical improvement.

Toxicity profiles and protective effects of antifreeze proteins from insect in mammalian models.

Antifreeze proteins (AFPs), found in many cold-adapted organisms, can protect them from cold and freezing damages and have thus been considered as additional protectants in current cold tissue preservation solutions that generally include electrolytes, osmotic agents, colloids and antioxidants, to reduce the loss of tissue viability associated with cold-preservation. Due to the lack of toxicity profile studies on AFPs, their inclusion in cold preservation solutions has been a trial-and-error process limiting the development of AFPs' application in cold preservation. To assess the feasibility of translating the technology of AFPs for mammalian cell cold or cryopreservation, we determined the toxicity profile of two highly active beetle AFPs, DAFP1 and TmAFP, from Dendroides canadensis and Tenebrio molitor in this study. Toxicity was examined on a panel of representative mammalian cell lines including testicular spermatogonial stem cells and Leydig cells, macrophages, and hepatocytes. Treatments with DAFP1 and TmAFP at up to 500 µg/mL for 48 and 72 h were safe in three of the cell lines, except for a 20% decrease in spermatogonia treated with TmAFP. However, both AFPs at 500 µg/mL or below reduced hepatocyte viability by 20-40% at 48 and 72 h. At 1000 µg/mL, DAFP1 and TmAFP reduced viability in most cell lines. While spermatogonia and Leydig cell functions were not affected by 1000 µg/mL DAFP1, this treatment induced inflammatory responses in macrophages. Adding 1000 µg/mL DAFP1 to rat kidneys stored at 4 °C for 48 h protected the tissues from cold-related damage, based on tissue morphology and gene and protein expression of two markers of kidney function. However, DAFP1 and TmAFP did not prevent the adverse effects of cold on kidneys over 72 h. Overall, DAFP1 is less toxic at high dose than TmAFP, and has potential for use in tissue preservation at doses up to 500 µg/mL. However, careful consideration must be taken due to the proinflammatory potential of DAFP1 on macrophages at higher doses and the heighten susceptibility of hepatocytes to both AFPs.

Realidad virtual de bajo coste. Una nueva aplicación para rehabilitación motora de los miembros superiores en patología neurológica: Estudio piloto / Low-cost virtual reality. A new application for upper extremity motor rehabilitation in neurological pathology: Pilot study

Antecedentes y objetivo: El objetivo de este estudio es presentar una nueva aplicación de realidad virtual (RV) de bajo coste basada en el dispositivo Leap Motion Controller (LMC) desarrollada para la rehabilitación motora de miembros superiores tras patología neurológica y mostrar su viabilidad clínica realizando una experiencia piloto. Material y métodos: El LMC permite la interacción con las aplicaciones virtuales mediante la captación de los movimientos de la mano. Se realizó una prueba piloto con cuatro pacientes con afectación de miembros superiores con Upper Extremity Motor Score (UEMS) mayor de 10. Se les valoró con los test Box and Block (BBT) y tarea de escritura del Jebsen-Taylor Hand Function (JTHF) antes y después de la intervención. Resultados: Los pacientes completaron el protocolo de nueve sesiones de 30 minutos de duración dividido en tres sesiones por semana. En el BBT pasaron de 38 (DE 20) cubos antes de la intervención a 44 (DE 21,72) cubos tras finalizarla. En el JTHF pasaron de 28,25 s (DE 8,61) a 26, 75 s (DE 21,72). No hubo diferencias estadísticamente significativas. La usabilidad del dispositivo se valoró con la escala Quebec User Evaluation of Satisfaction with assistive Technology, versión 2.0 (QUEST) siendo la seguridad, efectividad y facilidad de uso los aspectos prioritarios. Conclusión: Se presenta un nuevo desarrollo de RV basado en el dispositivo LMC y se ha comprobado su viabilidad clínica en pacientes neurológicos con afectación de los miembros superiores. Es preciso realizar un estudio clínico con una muestra amplia para valorar su posible efectividad clínica como elemento de tratamiento.(AU)

Background and objectives: The aim of this study is to present a new virtual reality (VR) low cost application based on Leap Motion Controller (LMC) device for upper extremity motor rehabilitation after neurological pathology and to demonstrate its clinical feasibility by carrying out a pilot experience. Material and methods: The LMC allows the interaction with virtual applications by capturing the patient's hand movements. A pilot study was carried out with 4 patients with upper limb impairment reflected with Upper Extremity Motor Score (UEMS) greater than 10. They were assessed using the Box and Block (BBT) and the writing task within the Jebsen-Taylor Hand Function (JTHF) before and after the intervention. Results: All patients completed the 9-session, 30-min protocol divided into 3 sessions per week. They went from an average result of 38 (SD 20) blocks in BBT before the intervention to 44 (SD 21.72) after it. They went from 28.25 s (SD 8.61) to 26.75 s (SD 21.72) in the JTHF. Statistically significant differences were no found. The device usability was assessed by the QUEST scale, being the security, effectiveness and ease to use the aspects that patients considered to be a priority. Conclusión: A new VR development based on the LMC device is presented and the clinical feasibility of its application in neurological patients with upper limb involvement has been proven. A clinical study with a large sample size is needed to assess its potential clinical effectiveness as a treatment element.(AU)

The Impact of Robotic Therapy on the Self-Perception of Upper Limb Function in Cervical Spinal Cord Injury: A Pilot Randomized Controlled Trial.

BACKGROUND: The aim of the present study was to evaluate the impact of robotic therapy in patients with cervical spinal cord injury (SCI), measured on the basis of the patients' self-perception of limited upper limb function and level of independence in activities of daily living. METHODS: Twenty-six patients with cervical SCI completed the treatment after being randomly assigned to the intervention or control group. The training consisted of 40 experimental sessions 1 h in duration, ideally occurring 5 days/week for 8 weeks. In addition to the conventional daily therapy (30 min), the control group received another 30 min of conventional therapy, whereas the intervention group received 30 min of robotic therapy. Patients were evaluated by means of the Capabilities of Upper Extremity Questionnaire (CUE) and Spinal Cord Independence Measure (SCIM) clinical scales. RESULTS: The improvement in the feeding item of SCIM was significantly higher in the intervention group than in the control group after the treatment (2.00 (0.91) vs. 1.18 (0.89), p = 0.03). The correlation between the CUE and SCIM scales was higher at the ending than at baseline for both groups. CONCLUSIONS: Although both groups improved, the clinical relevance related to the changes observed for both assessments was slightly higher in the intervention group than in the control group.

Protection From Radiation-Induced Neuroanatomic Deficits by CCL2 Deficiency Is Dependent on Sex.

PURPOSE: Cranial radiation therapy for the treatment of pediatric brain tumors results in changes to brain development that are detectable with magnetic resonance imaging. We have previously demonstrated similar structural changes in both humans and mice. The goal of the current study was to examine the role of inflammation in this response. Because neuroanatomic volume deficits in pediatric survivors are more pronounced in female patients, we also evaluated possible dependence on sex. METHODS AND MATERIALS: Other studies have shown that male mice deficient in the C-C chemokine ligand 2 gene (Ccl2; previously Mcp-1) have a muted neuroinflammatory response after irradiation. We irradiated Ccl2-/- (HOM; female = 12, male = 13), Ccl2-/+ (HET; female = 13, male = 16), and Ccl2+/+ (WT; female = 11, male = 13) mice with a whole brain dose of 7 Gy during infancy. Control mice (with approximately equal group sizes) were anesthetized but not irradiated. In vivo magnetic resonance images were acquired at 4 time points up to 3 months after irradiation, and deformation-based morphometry was used to identify volume differences. RESULTS: Irradiation of WT mice resulted in a deficit in neuroanatomic growth with limited sex dependence. HOM and HET male mice were significantly protected from this radiation-induced damage, whereas HOM and HET female mice were not. CONCLUSIONS: Interventions aimed at mitigating the effects of cranial radiation therapy in pediatric cancer survivors by modulating inflammatory response will need to consider patient sex.

A Review of the EUSO-Balloon Pathfinder for the JEM-EUSO Program.

EUSO-Balloon is a pathfinder for JEM-EUSO, the mission concept of a spaceborne observatory which is designed to observe Ultra-High Energy Cosmic Ray (UHECR)-induced Extensive Air Showers (EAS) by detecting their UltraViolet (UV) light tracks "from above." On August 25, 2014, EUSO-Balloon was launched from Timmins Stratospheric Balloon Base (Ontario, Canada) by the balloon division of the French Space Agency CNES. After reaching a floating altitude of 38 km, EUSO-Balloon imaged the UV light in the wavelength range ∼290-500 nm for more than 5 hours using the key technologies of JEM-EUSO. The flight allowed a good understanding of the performance of the detector to be developed, giving insights into possible improvements to be applied to future missions. A detailed measurement of the photoelectron counts in different atmospheric and ground conditions was achieved. By means of the simulation of the instrument response and by assuming atmospheric models, the absolute intensity of diffuse light was estimated. The instrument detected hundreds of laser tracks with similar characteristics to EASs shot by a helicopter flying underneath. These are the first recorded laser tracks measured from a fluorescence detector looking down on the atmosphere. The reconstruction of the direction of the laser tracks was performed. In this work, a review of the main results obtained by EUSO-Balloon is presented as well as implications for future space-based observations of UHECRs.

[Functional evaluation with the KSS (Knee Society Score) scale at 3 and 6 months after ligament reconstruction in patients with multi-ligament knee injuries in a third level hospital]. / Evaluación funcional con la escala KSS (Knee Society Score) a tres y seis meses de la reconstrucción ligamentaria en pacientes con lesiones multiligamentarias de rodilla en un hospital de tercer nivel.

Multiligament injuries of the knee joint are characterized by the involvement of two or more major ligaments, anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), lateral collateral ligament (LCL), posteromedial corner (PMC) and posterolateral corner (PLC). Statistically, multiligament injuries are rare as they are found in less than 0.02% of all traumatic knee injuries; however, different aggregate injuries are what make this pathology a serious health and functional condition. Taking into account that most of the patients are young people of highly productive age, it is of vital importance to observe their short and long term evolution, as well as their reincorporation to their daily life. It has been reported that vascular lesions are present in approximately 32% of cases, meniscal lesions in 35% and up to 60% with some type of bone lesion. These injuries mainly affect the male sex most commonly between the third and fourth decade of life, which makes this type of injury of great importance, since this group of patients are in their greatest period of labor production. The main objective of the treatment of these injuries, in addition to resolving the aggregate damage that usually aggravates the state of health, is to achieve a speedy recovery and subsequent reincorporation to their work activities and in some cases sports.

Las lesiones multiligamentarias de la articulación de la rodilla se caracterizan por la afección de dos o más ligamentos principales, ligamento cruzado anterior (LCA), ligamento cruzado posterior (LCP), ligamento colateral medial (LCM), ligamento colateral lateral (LCL), esquina posteromedial (EPM) y esquina posterolateral (EPL). Estadísticamente, las lesiones multiligamentarias son poco frecuentes, ya que se encuentran en menos de 0.02% de todas las lesiones traumáticas de rodilla; sin embargo, diferentes lesiones agregadas son las que hacen de esta patología un estado grave para salud y funcionalidad. Tomando en cuenta que la mayoría de los pacientes son personas jóvenes en edad altamente productiva, es de vital importancia observar la evolución de los mismos a corto y largo plazo, así como su reincorporación a su vida cotidiana. Se ha descrito que las lesiones vasculares se presentan aproximadamente en 32% de los casos, lesiones meniscales en 35% y hasta 60% con algún tipo de lesión ósea. Estas lesiones afectan principalmente al sexo masculino con más frecuencia entre la tercera y cuarta década de la vida, lo cual hace a este tipo de lesiones de gran importancia, ya que este grupo de pacientes se encuentran en su mayor período de producción laboral. El objetivo principal del tratamiento de estas lesiones, además de resolver los daños agregados que suelen ser los agravantes del estado de salud, es lograr una pronta recuperación y posterior reincorporación a sus actividades laborales y en algunos casos deportivas.

[Low-cost virtual reality. A new application for upper extremity motor rehabilitation in neurological pathology: Pilot study]. / Realidad virtual de bajo coste. Una nueva aplicación para rehabilitación motora de los miembros superiores en patología neurológica: Estudio piloto.

BACKGROUND AND OBJECTIVES: The aim of this study is to present a new virtual reality (VR) low cost application based on Leap Motion Controller (LMC) device for upper extremity motor rehabilitation after neurological pathology and to demonstrate its clinical feasibility by carrying out a pilot experience. MATERIAL AND METHODS: The LMC allows the interaction with virtual applications by capturing the patient's hand movements. A pilot study was carried out with 4 patients with upper limb impairment reflected with Upper Extremity Motor Score (UEMS) greater than 10. They were assessed using the Box and Block (BBT) and the writing task within the Jebsen-Taylor Hand Function (JTHF) before and after the intervention. RESULTS: All patients completed the 9-session, 30-min protocol divided into 3 sessions per week. They went from an average result of 38 (SD 20) blocks in BBT before the intervention to 44 (SD 21.72) after it. They went from 28.25 s (SD 8.61) to 26.75 s (SD 21.72) in the JTHF. Statistically significant differences were no found. The device usability was assessed by the QUEST scale, being the security, effectiveness and ease to use the aspects that patients considered to be a priority. CONCLUSIóN: A new VR development based on the LMC device is presented and the clinical feasibility of its application in neurological patients with upper limb involvement has been proven. A clinical study with a large sample size is needed to assess its potential clinical effectiveness as a treatment element.

Exploring the Emerging Domain of Research on Video Game Live Streaming in Web of Science: State of the Art, Changes and Trends.

In recent years, interest in video game live streaming services has increased as a new communication instrument, social network, source of leisure, and entertainment platform for millions of users. The rise in this type of service has been accompanied by an increase in research on these platforms. As an emerging domain of research focused on this novel phenomenon takes shape, it is necessary to delve into its nature and antecedents. The main objective of this research is to provide a comprehensive reference that allows future analyses to be addressed with greater rigor and theoretical depth. In this work, we developed a meta-review of the literature supported by a bibliometric performance and network analysis (BPNA). We used the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) protocol to obtain a representative sample of 111 published documents since 2012 and indexed in the Web of Science. Additionally, we exposed the main research topics developed to date, which allowed us to detect future research challenges and trends. The findings revealed four specializations or subdomains: studies focused on the transmitter or streamer; the receiver or the audience; the channel or platform; and the transmission process. These four specializations add to the accumulated knowledge through the development of six core themes that emerge: motivations, behaviors, monetization of activities, quality of experience, use of social networks and media, and gender issues.

Entropy, purity and optical hysteresis in markovian optical modes.

We describe the synthesis of optical modes whose axial structure follows a random tandem array of Bessel beams of integer order. The array follows fluctuations of Markov-chain type and the amplitude values for each beam are linked to a sequence of random vectors. As a prototype, we describe the synthesis of optical fields for Markov-chain type Ehrenfest. This process models the thermodynamic equilibrium and then it can be related to the evolution and stability of optical systems, in this way, it offers a similitude with partially coherent processes where the coherence degree is now distributed between all the compounds of the resulting random vector. The matrix representation for the stochastic process allows incorporating entropy properties and the calculus of the purity for the optical field. This constitutes the basis to describe the interference between markovian modes. When the set of markovian modes type Ehrenfest reaches a stable configuration they become indistinguishability non-conservative optical field having associated hysteresis features. Computer simulations are presented.

Arginase-1 deficiency in neural cells does not contribute to neurodevelopment or functional outcomes after sciatic nerve injury.

Arginase-1 (Arg1) is an enzyme controlling the final step of the urea cycle, with highest expression in the liver and lower expression in the lungs, pancreas, kidney, and some blood cells. Arg1 deficiency is an inherited urea cycle disorder presenting with neurological dysfunction including spastic diplegia, intellectual and growth retardation, and encephalopathy. The contribution of Arg1 expression in the central and peripheral nervous system to the development of neurological phenotypes remains largely unknown. Previous studies have shown prominent arginase-1 expression in the nervous system and post-peripheral nerve injury in mice, but very low levels in the naïve state. To investigate neurobiological roles of Arg1, we created a conditional neural (n)Arg1 knockout (KO) mouse strain, with expression eliminated in neuronal and glial precursors, and compared them to littermate controls. Long-term analysis did not reveal any major differences in blood amino acid levels, body weight, or stride gait cycle from 8 to 26-weeks of age. Brain structure measured by magnetic resonance imaging at 16-weeks of age observed only a significant decrease in the volume of the mammillary bodies. We also assessed whether nArg1, which is expressed by sensory neurons after injury, may play a role in regeneration following sciatic nerve crush. Only subtle differences were observed in locomotor and sensory recovery between nArg1 KO and control mice. These results suggest that arginase-1 expression in central and peripheral neural cells does not contribute substantially to the phenotypes of this urea cycle disorder, nor is it likely crucial for post-injury regeneration in this mouse model.

The influence of high-density lipoprotein (HDL) and HDL subfractions on insulin secretion and cholesterol efflux in pancreatic derived ß-cells.

BACKGROUND: High-density lipoprotein (HDL) is considered a complex plasma-circulating particle with subfractions that vary in function, size, and chemical composition. We sought to test the effects of HDL, and HDL subfractions on insulin secretion and cholesterol efflux in the ß-cell line MIN-6. METHODS: We used total HDL and HDL subfractions 2a, 2b, 3a, 3b, and 3c, isolated from human plasma, to test insulin secretion under different glucose concentrations as well as insulin content and cholesterol efflux in the insulinoma MIN-6 cell line. RESULTS: Incubation of MIN-6 cells with low glucose and total HDL increased insulin release two-fold. Meanwhile, when high glucose and HDL were used, insulin release increased more than five times. HDL subfractions 2a, 2b, 3a, 3b, and 3c elicited higher insulin secretion and cholesterol efflux than their respective controls, at both low and high glucose concentrations. The insulin content of the MIN-6 cells incubated with low glucose and any of the five HDL subclasses had a modest reduction compared with their controls. However, there were no statistically significant differences between each HDL subfraction on their capacity of eliciting insulin secretion, insulin content, or cholesterol efflux. CONCLUSIONS: HDL can trigger insulin secretion under low, normal, and high glucose conditions. We found that all HDL subfractions exhibit very similar capacity to increase insulin secretion and cholesterol efflux. This is the first report demonstrating that HDL subfractions act both as insulin secretagogues (under low glucose) and insulin secretion enhancers (under high glucose) in the MIN-6 cell line.

The -514C>T polymorphism in the LIPC gene modifies type 2 diabetes risk through modulation of HDL-cholesterol levels in Mexicans.

PURPOSE: Both type 2 diabetes (T2D) and low levels of high-density lipoprotein cholesterol (HDL-C) are very prevalent conditions among Mexicans. Genetic variants in the LIPC gene have been associated with both conditions. This study aimed to evaluate the association of the -514C < T (rs1800588) LIPC gene polymorphism with different metabolic traits, particularly the effects of this polymorphism on HDL-C plasma levels and T2D risk. METHODS: Mediation analysis was used to assess the direct and indirect effects of the -514C>T LIPC gene variant on HDL-C levels, T2D risk, and body mass index (BMI), in 2105 Mexican mestizo participants. We also assessed the functional effect of the -514C>T LIPC variant on the promoter activity of a reporter gene in the HepG2 cell line. RESULTS: Direct effects show that the -514C>T LIPC polymorphism is significantly associated with increased HDL-C plasma levels (ß = 0.03; p < 0.001). The -514C>T variant resulted in an indirect protective effect on T2D risk through increasing HDL-C levels (ß = - 0.03; p < 0.001). Marginal direct association between -514C>T and T2D was found (ß = 0.08; p = 0.06). Variables directly influencing T2D status were European ethnicity (ß = - 7.20; p < 0.001), age (ß = 0.04; p < 0.001), gender (ß = - 0.15; p = 0.017) and HDL-C (ß = - 1.07; p < 0.001). In addition, we found that the -514C>T variant decreases the activity of LIPC promoter by 90% (p < 0.001). CONCLUSIONS: The -514C>T polymorphism was not directly associated with T2D risk. HDL-C acts as a mediator between -514C>T LIPC gene variant and T2D risk in the Mexican population.

Invariant correlated optical fields driven by multiplicative noise.

We describe the evolution of a linear transmittance when it is perturbed with multiplicative noise; the evolution is approximated through an ensemble of random transmittances that are used to generate diffraction fields. The randomness induces a competition mechanism between noise and transmittance, and it is identified through the self-correlation function. We show that the geometry of the self-correlation function is a single peak preserved in the diffraction field that can be matched with localization-like effects. To corroborate the theoretical predictions, we perform an experiment using a linear grating where the noise is approximated by a stochastic Markov chain. Experimental results are shown.