Precision Delivery of Steroids as a Rescue Therapy for Gastrointestinal Graft-versus-Host Disease in Pediatric Stem Cell Transplant Recipients.

Graft versus host disease (GVHD) is one of the most serious complications following stem cell transplant in children and is a major cause of morbidity and mortality. Corticosteroids remain the mainstay of treatment, and although a majority of children respond to systemic steroids, those refractory to or dependent upon corticosteroids suffer from complications secondary to long-term steroid administration. This problem has prompted consideration of steroid-sparing treatment strategies, although the time to clinical remission can be variable. Intraarterial corticosteroid delivery has been used in adults as a rescue therapy in steroid-resistant patients, but its use in children has been limited. We investigated the feasibility of intraarterial steroid administration into the bowel and/or liver in a cohort of six pediatric patients with acute GVHD. All patients successfully underwent treatment with no serious adverse effects. Five of five (100%) patients with gastrointestinal bleeding due to GVHD had rapid symptom improvement by 48 h, which was durable up to three weeks. Three of four (75%) patients with hepatic GVHD had improved cholestasis following intraarterial steroid administration. Our experience with this small cohort preliminarily demonstrated the feasibility and safety of intraarterial steroid administration in children with acute GVHD. This approach warrants consideration as a rescue therapy in steroid-refractory cases and as a "bridge" therapy for children with severe acute GVHD who are transitioning to steroid-sparing regimens.

Ecosystem resilience to invasion and drought: Insights after 24 years in a rare never-grazed grassland.

Understanding the resilience of ecosystems globally is hampered by the complex and interacting drivers of change characteristic of the Anthropocene. This is true for drylands of the western US, where widespread alteration of disturbance regimes and spread of invasive non-native species occurred with westward expansion during the 1800s, including the introduction of domestic livestock and spread of Bromus tectorum, an invasive non-native annual grass. In addition, this region has experienced a multi-decadal drought not seen for at least 1200 years with potentially large and interacting impacts on native plant communities. Here, we present 24 years of twice-annual plant cover monitoring (1997-2021) from a semiarid grassland never grazed by domestic livestock but subject to a patchy invasion of B. tectorum beginning in ~1994, compare our findings to surveys done in 1967, and examine potential climate drivers of plant community changes. We found a significant warming trend in the study area, with more than 75% of study year temperatures being warmer than average (1966-2021). We observed a native perennial grass community with high resilience to climate forcings with cover values like those in 1967. In invaded patches, B. tectorum cover was greatest in the early years of this study (1997-2001; ~20%-40%) but was subsequently constrained by climate and subtle variation in soils, with limited evidence of long-term impacts to native vegetation, contradicting earlier studies. Our ability to predict year-to-year variation in functional group and species cover with climate metrics varied, with a 12-month integrated index and fall and winter patterns appearing most important. However, declines to near zero live cover in recent years in response to regional drought intensification leave questions regarding the resiliency of intact grasslands to ongoing aridification and whether the vegetation observations reported here may be a leading indicator of impending change in this protected ecosystem.

Una década después de la implantación en España de la hipotermia terapéutica en el recién nacido con encefalopatía hipóxico-isquémica perinatal / Ten years since the introduction of therapeutic hypothermia in neonates with perinatal hypoxic-ischaemic encephalopathy in Spain

Introducción: Se cumple ahora más de una década del inicio de la hipotermia terapéutica (HT)en Espa ̃na, la única intervención neuroprotectora que ha venido a ser práctica estándar en eltratamiento de la encefalopatía hipóxico-isquémica perinatal (EHI). El objetivo de este artículoes ofrecer un panorama actual y presentar las controversias surgidas alrededor de la aplicaciónde esta terapia. Desarrollo: En esta década se ha implantado con éxito la HT en la gran mayoría de los hospitalesterciarios de Espa ̃na y más del 85% de los recién nacidos con EHI moderada-grave reciben estaterapia. Entre los aspectos que pueden mejorar la eficacia de la HT están su inicio precoz dentrode las primeras 6 h de vida y el control de factores comórbidos asociados a la asfixia perinatal. En los pacientes con EHI moderada el inicio después de las 6 h parece mantener cierta eficacianeuroprotectora. Una duración de la HT mayor de 72 horas o un enfriamiento más profundo noofrecen mayor eficacia neuroprotectora y aumentan el riesgo de efectos adversos. Aspectosno bien aclarados aún son la sedación durante la HT y la aplicación de esta intervención a losneonatos con EHI leve y en otros escenarios. La información pronóstica y su marco temporal esuno de los aspectos más desafiantes. Conclusiones: La HT es universal en países con recursos económicos, aunque existen puntos de controversia no resueltos. Si bien es un tratamiento generalizado en nuestro país, falta disponerde dispositivos para el traslado de estos pacientes y su centralización.(AU)

Introduction: More than a decade has passed since therapeutic hypothermia (TH) was introduced in Spain; this is the only neuroprotective intervention that has become standard practice inthe treatment of perinatal hypoxic-ischaemic encephalopathy (HIE). This article aims to providea current picture of the technique and to address the controversies surrounding its use. Development: In the last 10 years, TH has been successfully implemented in the vast majority of tertiary hospitals in Spain, and more than 85% of newborns with moderate or severeHIE currently receive the treatment. The factors that can improve the efficacy of TH includeearly treatment onset (first 6 hours of life) and the control of comorbid factors associated withperinatal asphyxia. In patients with moderate HIE, treatment onset after 6 hours seems to havesome neuroprotective efficacy. TH duration longer than 72 hours or deeper hypothermia do notoffer greater neuroprotective efficacy, but instead increase the risk of adverse effects. Unclarified aspects are the sedation of patients during TH, the application of the treatment in infantswith mild HIE, and its application in other scenarios. Prognostic information and time frame areone of the most challenging aspects. Conclusions: TH is universal in countries with sufficient economic resources, although certainunresolved controversies remain. While the treatment is widespread in Spain, there is a needfor cooling devices for the transfer of these patients and their centralisation.(AU)

Ten years since the introduction of therapeutic hypothermia in neonates with perinatal hypoxic-ischaemic encephalopathy in Spain.

INTRODUCTION: More than a decade has passed since therapeutic hypothermia (TH) was introduced in Spain; this is the only neuroprotective intervention that has become standard practice in the treatment of perinatal hypoxic-ischaemic encephalopathy (HIE). This article aims to provide a current picture of the technique and to address the controversies surrounding its use. DEVELOPMENT: In the last 10 years, TH has been successfully implemented in the vast majority of tertiary hospitals in Spain, and more than 85% of newborns with moderate or severe HIE currently receive the treatment. The factors that can improve the efficacy of TH include early treatment onset (first 6 h of life) and the control of comorbid factors associated with perinatal asphyxia. In patients with moderate HIE, treatment onset after 6 h seems to have some neuroprotective efficacy. TH duration longer than 72 h or deeper hypothermia do not offer greater neuroprotective efficacy, but instead increase the risk of adverse effects. Controversy persists around the sedation of patients during TH, the application of the treatment in infants with mild HIE, and its application in other scenarios. Prognostic information and time frame are one of the most challenging aspects. CONCLUSIONS: TH is universal in countries with sufficient economic resources, although certain unresolved controversies remain. While the treatment is widespread in Spain, there is a need for devices for the transfer of these patients and their centralisation.

Recombination events drives the emergence of Colombian Helicobacter pylori subpopulations with self-identity ancestry.

Helicobacter pylori have coevolved with mankind since its origins, adapting to different human groups. In America, H. pylori has evolved into several subpopulations. We analysed the genome of 154 Colombian strains along with 1,091 strains from worldwide populations to discern the ancestry and adaption to Colombian people. Population structure and ancestry was inferred with FineStructure and ChromoPainter. Phylogenetic relationship and the relative effect of recombination were analysing the core SNPs. Also, a Fst index was calculated to identify the gene variants with the strongest fixation in the Colombian subpopulations compared to their parent population hspSWEurope. FineStructure allowed the identification of two Colombian subpopulations, the previously described hspSWEuropeColombia and a novel subpopulation named hspColombia, that included three subgroups following their geographic origin. Colombian subpopulations represent an admixture of European, African and Indigenous ancestry; although some genomes showed a high proportion of self identity, suggesting an advanced adaption to these mestizo Colombian groups. We found that recombination is more important that punctual mutations in H. pylori genome diversity, 13.9 more important in hspSWEurope, 12.5 in hspSWEColombia and 10.5 in hspColombia, reflecting the divergence of these subpopulations. Fst analysis identified 82 SNPs fixed in 26 genes of the hspColombia subpopulation that encode for outer membrane and central metabolism proteins. Strongest fixation indexes were identified in genes encoding HofC, HopE, FrpB-4 and Sialidase A. These findings demonstrate that H. pylori has evolved in Colombia to give rise to subpopulations with a self identity ancestry, reflected in allele changes on genes encoding for outer membrane proteins.

MRAP2 inhibits ß-arrestin recruitment to the ghrelin receptor by preventing GHSR1a phosphorylation.

The melanocortin receptor accessory protein 2 (MRAP2) is essential for several physiological functions of the ghrelin receptor growth hormone secretagogue receptor 1a (GHSR1a), including increasing appetite and suppressing insulin secretion. In the absence of MRAP2, GHSR1a displays high constitutive activity and a weak G-protein-mediated response to ghrelin and readily recruits ß-arrestin. In the presence of MRAP2, however, G-protein-mediated signaling via GHSR1a is strongly dependent on ghrelin stimulation and the recruitment of ß-arrestin is significantly diminished. To better understand how MRAP2 modifies GHSR1a signaling, here we investigated the role of several phosphorylation sites within the C-terminal tail and third intracellular loop of GHSR1a, as well as the mechanism behind MRAP2-mediated inhibition of ß-arrestin recruitment. We show that Ser252 and Thr261 in the third intracellular loop of GHSR1a contribute to ß-arrestin recruitment, whereas the C-terminal region is not essential for ß-arrestin interaction. Additionally, we found that MRAP2 inhibits GHSR1a phosphorylation by blocking the interaction of GRK2 and PKC with the receptor. Taken together, these data suggest that MRAP2 alters GHSR1a signaling by directly impacting the phosphorylation state of the receptor and that the C-terminal tail of GHSR1a prevents rather than contribute to ß-arrestin recruitment.

Decline in biological soil crust N-fixing lichens linked to increasing summertime temperatures.

Biological soil crusts (biocrusts), comprised of mosses, lichens, and cyanobacteria, are key components to many dryland communities. Climate change and other anthropogenic disturbances are thought to cause a decline in mosses and lichens, yet few long-term studies exist to track potential shifts in these sensitive soil-surface communities. Using a unique long-term observational dataset from a temperate dryland with initial observations dating back to 1967, we examine the effects of 53 y of observed environmental variation and Bromus tectorum invasion on biocrust communities in a grassland never grazed by domestic livestock. Annual observations show a steep decline in N-fixing lichen cover (dominated by Collema species) from 1996 to 2002, coinciding with a period of extended drought, with Collema communities never able to recover. Declines in other lichen species were also observed, both in number of species present and by total cover, which were attributed to increasing summertime temperatures. Conversely, moss species gradually gained in cover over the survey years, especially following a large Bromus tectorum invasion at the study onset (ca. 1996 to 2001). These results support a growing body of studies that suggests climate change is a key driver in changes to certain components of late-successional biocrust communities. Results here suggest that warming may partially negate decades of protection from disturbance, with biocrust communities reaching a vital tipping point. The accelerated rate of ongoing warming observed in this study may have resulted in the loss of lichen cover and diversity, which could have long-term implications for global temperate dryland ecosystems.

Multiregional Sequencing Analysis Reveals Extensive Genetic Heterogeneity in Gastric Tumors from Latinos.

Gastric cancer is a leading cause of cancer mortality and health disparities in Latinos. We evaluated gastric intratumoral heterogeneity using multiregional sequencing of >700 cancer genes in 115 tumor biopsies from 32 patients, 29 who were Latinos. Analyses focused on comparisons with The Cancer Genome Atlas (TCGA) and on mutation clonality, druggability, and signatures. We found that only approximately 30% of all mutations were clonal and that only 61% of the known TCGA gastric cancer drivers harbored clonal mutations. Multiple clonal mutations were found in new candidate gastric cancer drivers such as EYS, FAT4, PCDHA1, RAD50, EXO1, RECQL4, and FSIP2. The genomically stable (GS) molecular subtype, which has the worse prognosis, was identified in 48% of our Latino patients, a fraction that was >2.3-fold higher than in TCGA Asian and White patients. Only a third of all tumors harbored clonal pathogenic mutations in druggable genes, with most (93%) GS tumors lacking actionable clonal mutations. Mutation signature analyses revealed that, in microsatellite-stable (MSS) tumors, DNA repair mutations were common for both tumor initiation and progression, while tobacco, POLE, and inflammation signatures likely initiate carcinogenesis. MSS tumor progression was likely driven by aging- and aflatoxin-associated mutations, as these latter changes were usually nonclonal. In microsatellite-unstable tumors, nonclonal tobacco-associated mutations were common. Our study, therefore, contributed to advancing gastric cancer molecular diagnostics and suggests clonal status is important to understanding gastric tumorigenesis. Our findings of a higher frequency of a poor prognosis associated molecular subtype in Latinos and a possible new aflatoxin gastric cancer etiology also advance cancer disparities research. Significance: Our study contributes to advancing our knowledge of gastric carcinogenesis, diagnostics, and cancer health disparities.

[Quality management of the experimental health products circuit in hospital pharmacies: National inventory and proposed standardised tools]. / Management de la qualité du circuit des produits de santé expérimentaux dans les pharmacies hospitalières : enquête nationale et développement d'outils standardisés.

OBJECTIVES: Carry out a national inventory of the current situation regarding the quality management of the investigational health products circuit, to develop adapted standardised tools. METHODS: A survey of 76 questions, developed by a regional working group, was conducted among clinical research pharmacists in French facilities. Tools were developed to meet the identified needs and validated by participating pharmacists, using the Delphi method. The consensus was defined by achieving a score above 80% on relevance, clarity and evaluability. RESULTS: Among 94 pharmacists participating in the survey, 88 were interested in standardised tools. The score for the implementation of a quality approach depended on the type of health facility (P<0.0005) and increased with the number of active trials (P<0.0005). All nine proposed tools were useful for over two thirds of pharmacists, but the self-assessment and audit grids have been prioritised. Indeed, only 26% of pharmacies carried out a prior risk assessment and 14% carried out internal audits. The review of both grids led to a consensus on 89% and 97% of the criteria respectively. The validated grids include 62 and 72 criteria respectively. DISCUSSION: The quality approach of the investigational health products circuit is heterogeneous in the participating centres, with a strong need for standardised tools. The two grids are relevant tools developed by and for professionals. CONCLUSION: The tools developed will enable to optimise the quality approach by identifying the non-conformities of the investigational health products circuit.

Bedside and laboratory neuromonitoring in neonatal encephalopathy.

Several bedside and laboratory neuromonitoring tools are currently used in neonatal encephalopathy (NE) to assess 1) brain function [amplitude-integrated electroencephalogram (aEEG) and EEG], 2) cerebral oxygenation delivery and consumption [near-infrared spectroscopy (NIRS)] and 3) blood and cerebrospinal fluid biomarkers. The aim of the review is to provide the role of neuromonitoring in understanding the development of brain injury in these newborns and better predict their long-term outcome. Simultaneous use of these monitoring modalities may improve our ability to provide meaningful prognostic information regarding ongoing treatments. Evidence will be summarized in this review for each of these modalities, by describing (1) the methods, (2) the clinical evidence in context of NE both before and with hypothermia, and (3) the research and future directions.

Ten years since the introduction of therapeutic hypothermia in neonates with perinatal hypoxic-ischaemic encephalopathy in Spain. / Una década después de la implantación en España de la hipotermia terapéutica en el recién nacido con encefalopatía hipóxico-isquémica perinatal.

INTRODUCTION: More than a decade has passed since therapeutic hypothermia (TH) was introduced in Spain; this is the only neuroprotective intervention that has become standard practice in the treatment of perinatal hypoxic-ischaemic encephalopathy (HIE). This article aims to provide a current picture of the technique and to address the controversies surrounding its use. DEVELOPMENT: In the last 10 years, TH has been successfully implemented in the vast majority of tertiary hospitals in Spain, and more than 85% of newborns with moderate or severe HIE currently receive the treatment. The factors that can improve the efficacy of TH include early treatment onset (first 6hours of life) and the control of comorbid factors associated with perinatal asphyxia. In patients with moderate HIE, treatment onset after 6hours seems to have some neuroprotective efficacy. TH duration longer than 72hours or deeper hypothermia do not offer greater neuroprotective efficacy, but instead increase the risk of adverse effects. Unclarified aspects are the sedation of patients during TH, the application of the treatment in infants with mild HIE, and its application in other scenarios. Prognostic information and time frame are one of the most challenging aspects. CONCLUSIONS: TH is universal in countries with sufficient economic resources, although certain unresolved controversies remain. While the treatment is widespread in Spain, there is a need for cooling devices for the transfer of these patients and their centralisation.

The Insulinostatic Effect of Ghrelin Requires MRAP2 Expression in δ Cells.

Ghrelin regulates both energy intake and glucose homeostasis. In the endocrine pancreas, ghrelin inhibits insulin release to prevent hypoglycemia during fasting. The mechanism through which this is accomplished is unclear, but recent studies suggest that ghrelin acts on δ cells to stimulate somatostatin release, which in turn inhibits insulin release from ß cells. Recently, the Melanocortin Receptor Accessory Protein 2 (MRAP2) was identified as an essential partner of the ghrelin receptor (GHSR1a) in mediating the central orexigenic action of ghrelin. In this study we show that MRAP2 is expressed in islet δ cells and is required for ghrelin to elicit a calcium response in those cells. Additionally, we show that both global and δ cell targeted deletion of MRAP2 abrogates the insulinostatic effect of ghrelin. Together, these findings establish that ghrelin signaling within δ cells is essential for the inhibition of insulin release and identify MRAP2 as a regulator of insulin secretion.

Genome Sequences of Three Colombian Helicobacter pylori Strains Isolated from Tolimense Patients.

We present the complete genome sequences of three Helicobacter pylori strains isolated from patients who resided in Tolima Department, Colombia, diagnosed with chronic gastritis. The genomes present an average length of 1.6 Mbp and 1,546 genes and correspond to different H. pylori subpopulations.

The GPCR accessory protein MRAP2 regulates both biased signaling and constitutive activity of the ghrelin receptor GHSR1a.

Ghrelin is a hormone secreted by the stomach during fasting periods and acts through its receptor, the growth hormone secretagogue 1a (GHSR1a), to promote food intake and prevent hypoglycemia. As such, GHSR1a is an important regulator of energy and glucose homeostasis and a target for the treatment of obesity. Here, we showed that the accessory protein MRAP2 altered GHSR1a signaling by inhibiting its constitutive activity, as well as by enhancing its G protein-dependent signaling and blocking the recruitment and signaling of ß-arrestin in response to ghrelin. In addition, the effects of MRAP2 on the Gαq and ß-arrestin pathways were independent and involved distinct regions of MRAP2. These findings may have implications for the regulation of ghrelin function in vivo and the role of MRAP2 in energy homeostasis. They also show that accessory proteins can bias signaling downstream of GPCRs in response to their endogenous agonist.

MRAP2 regulates ghrelin receptor signaling and hunger sensing.

Ghrelin is the only known circulating orexigenic hormone. It is primarily secreted by the stomach and acts at its receptor, the growth hormone secretagogue receptor 1a (GHSR1a), in the hypothalamus to signal hunger and promote food intake. The melanocortin receptor accessory protein 2 (MRAP2) was previously shown to regulate energy homeostasis through the modulation of the activity of the melanocortin-4 receptor and prokineticin receptors. In this study we identify MRAP2 as a partner of ghrelin-GHSR1a signaling. We show that MRAP2 interacts with GHSR1a and potentiates ghrelin-stimulated signaling both in vitro and in vivo. We demonstrate that in the absence of MRAP2, fasting fails to activate agouti-related protein neurons. In addition, we show that the orexigenic effect of ghrelin is lost in mice lacking MRAP2. Our results suggest that MRAP2 is an important modulator of the energy homeostasis machinery that operates through the regulation of multiple GPCRs throughout the hypothalamus.Melanocortin receptor accessory protein 2 (MRAP2) is an adaptor protein that contributes to melanocortin-4 receptor and prokineticin receptor 1 signalling. Here the authors show that MRAP2 also regulates ghrelin receptor signalling in the hypothalamus and starvation sensing in mice.

Regions of MRAP2 required for the inhibition of orexin and prokineticin receptor signaling.

The Melanocortin Receptor Accessory Protein 2 (MRAP2) regulates the activity of several GPCRs involved in the control of food intake and energy expenditure. While MRAP2 was originally thought to exclusively interact with melanocortin receptors we have recently shown that it interacts with and inhibits the trafficking and signaling of the prokineticin receptor 1 (PKR1). In this study we demonstrate a new role of MRAP2 in the regulation of the orexin receptor 1 (OX1R) and identify the specific regions of MRAP2 required for the regulation of OX1R and PKR1. Importantly, like MC4R and PKRs, OX1R is predominately expressed in the brain where it regulates food intake. By demonstrating that MRAP2 modulates the activity of OX1R we further establish the critical role of MRAP2 in the control of energy homeostasis.

Trait variation along elevation gradients in a dominant woody shrub is population-specific and driven by plasticity.

Elevation gradients are frequently used as space-for-time substitutions to infer species' trait responses to climate change. However, studies rarely investigate whether trait responses to elevation are widespread or population-specific within a species, and the relative genetic and plastic contributions to such trait responses may not be well understood. Here, we examine plant trait variation in the dominant woody shrub, Rhododendron maximum, along elevation gradients in three populations in the South Central Appalachian Mountains, USA, in both field and common garden environments. We ask the following: (i) do plant traits vary along elevation? (ii) do trait responses to elevation differ across populations, and if so, why? and (iii) does genetic differentiation or phenotypic plasticity drive trait variation within and among populations? We found that internode length, shoot length, leaf dry mass, and leaf area varied along elevation, but that these responses were generally unique to one population, suggesting that trait responses to environmental gradients are population-specific. A common garden experiment identified no genetic basis to variation along elevation or among populations in any trait, suggesting that plasticity drives local and regional trait variation and may play a key role in the persistence of plant species such as R. maximum with contemporary climate change. Overall, our findings highlight the importance of examining multiple locations in future elevation studies and indicate that, for a given plant species, the magnitude of trait responses to global climate change may vary by location.

Melanocortin Receptor Accessory Proteins (MRAPs): Functions in the melanocortin system and beyond.

G-protein coupled receptors (GPCRs) are regulated by numerous proteins including kinases, G-proteins, ß-arrestins and accessory proteins. Several families of GPCR accessory proteins like Receptor Activity Modifying Proteins, Receptor Transporting Proteins and Melanocortin Receptor Accessory Proteins (MRAPs) have been identified as regulator of receptor trafficking, signaling and ligand specificity. The MRAP family contains two members, MRAP1 and MRAP2, responsible for the formation of a functional ACTH receptor and for the regulation of energy homeostasis respectively. Like all known GPCR accessory proteins, MRAPs are single transmembrane proteins, however, they form a unique structure since they assemble as an anti-parallel homodimer. Moreover, the accepted idea that MRAPs are specific regulators of melanocortin receptors was recently challenged by the discovery that MRAP2 inhibits the activity of prokineticin receptors. Recent studies are starting to explain the role of the unusual structure of MRAPs and to illustrate the importance of MRAP2 for the maintenance of both energy and glucose homeostasis. This article is part of a Special Issue entitled: Melanocortin Receptors - edited by Ya-Xiong Tao.