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SummaryThe vast spectrum of clinical features of COVID-19 keeps challenging scientists and clinicians. Control of pathogen load (host resistance) and prevention of tissue damage (disease tolerance) are essential for the outcome of infectious diseases. Both low resistance and high disease tolerance might result in long-term viral persistence, but the underlying mechanisms remain unclear. Here, we studied the immune response of immunocompetent COVID-19 patients with prolonged SARS-CoV-2 infection by immunophenotyping, cytokine and serological analysis. Despite viral loads and symptoms comparable to regular mildly-symptomatic patients, long-term carriers displayed weaker systemic IFN-I responses and fewer circulating pDCs and NK cells at disease onset. Type 1 cytokines remained low, while type-3 cytokines were in turn enhanced. Interestingly, the plasma of these patients showed a higher spike-specific neutralization capacity. The identification of very early distinct immune responses in long-term carriers adds up to our understanding on essential host protective mechanisms to ensure tissue damage control despite prolonged viral infection.

The aim of this study is to analyze the skeletal and dentoalveolar morphological characteristics of the maxillary in subjects with a unilateral palatally impacted canine using Cone Beam Computed Tomography (CBCT). A retrospective clinical study was conducted of 100 adult patients divided into two groups: one consisting of patients with a unilaterally palatally impacted maxillary canine (GI), with the subgroups in the right and left hemiarches (GI-R and GI-L), and the second, without impacted canine, as the control group (CG). The CBCT measured skeletal variables (maxillary basal width and alveolar crest height) and dentoalveolar variables (inclination of the upper incisor, tooth lengths of incisors and canines, arch length, tooth size and bone dental discrepancy). In skeletal variables, statistically significant differences were found in alveolar crest height (ACH) in all groups and subgroups (p < 0.01). In the dentoalveolar variables, there were differences in the angle of the upper incisor (II) and lateral incisor length (LLIL) between the GI and GC and the angle of the upper incisor (II′), arch length (AL′) and arch length-tooth size discrepancy (ATD′) among the GI subgroups (p < 0.01). There are skeletal and dentoalveolar differences in patients with unilateral palatally impacted maxillary canines, with lower angular and linear measurements compared with patients without impaction.

The voltage-gated proton channel Hv1 regulates proton fluxes across membranes, thereby influencing pH-dependent processes. Plasmacytoid dendritic cells (pDCs) require a particularly tight regulation of endosomal pH to ensure strong type I IFN secretion exclusively during infection, avoiding autoimmunity. However, whether Hv1 is important for pH control in pDCs is presently unknown. In this study, we show that mouse pDCs require Hv1 to achieve potent type I IFN responses after the recognition of foreign DNA by endosomal TLR9. Genetic disruption of Hvcn1, which encodes Hv1, impaired mouse pDC activation by CpG oligonucleotides in vitro and in vivo, reducing IFN-α secretion and the induction of IFN-stimulated genes. Mechanistically, Hvcn1 deficiency delayed endosomal acidification and enhanced intracellular reactive oxygen species production, consequently limiting protease activity and TLR9 signaling. Our study reveals a critical role of Hv1 during innate immune responses and places this channel as a key modulator of type I IFN production, the hallmark function of pDCs, commending Hv1 as an attractive target for modulating type I IFN–driven autoimmunity.

To assess the PTS method in neuromonitoring of thoracic pedicle screws in a young cohort of AIS patients. The accuracy of both PTS (Pulse-train stimulation) and SPS (Single-pulse stimulation) techniques in the detection of misplaced thoracic screws was compared with special reference to the screws placed at the concavity and the convexity of the curve.A single-center prospective clinical cohort study.Twelve AIS patients who underwent elective surgery were included in this study. Screw stimulation using repetitive constant-current stimulus train of variable intensities was first performed after screw insertion. SPS was performed immediately after PTS. Postoperatively, CT scan was used to check the final position of the screws. A total of 246 thoracic pedicle screws were placed. Thresholds of screws placed in the convexity and the concavity were compared.Invasion of the spinal canal was postoperatively confirmed in 29 of the pedicle screws. The SPS technique detected three (10.3%) of these screws using a threshold limit of 12 mA. The PTS technique detected 25 (86.2%) of the 29 misplaced screws using threshold of 30 mA (negative predictive value, 93.1%). When using a PTS threshold of 20 mA, the positive predictive value was 70%. SPS did not detect any of the misplaced screws at the apex level of the scoliotic curves, and PTS detected 10 out of 17 of these screws. Overall, area under the ROC curve was 0.82 for PTS and 0.61 for SPS.PTS is a reliable method for detecting medially misplaced screws among young AIS patients undergoing scoliosis surgery. PTS provides more accurate predictions than SPS and improves the identification of screws invading the spinal canal at the apex or near the apex levels.

Glucocorticoids (GC) are widely used to treat acute relapses in multiple sclerosis (MS) patients, but their application is accompanied by side effects due to their broad spectrum of action. Here, we report on the therapeutic option to apply GC via inorganic-organic hybrid nanoparticles (IOH-NP) with the composition [ZrO]2+[(BMP)0.9(FMN)0.1]2- (designated BMP-NP with BMP: betamethasone phosphate; FMN: flavinmononucleotide). We found that these BMP-NP have an increased cell type-specificity compared to free GC while retaining full therapeutic efficacy in a mouse model of MS. BMP-NP were preferentially taken up by phagocytic cells and modulated macrophages in vivo more efficiently than T cells. When GC were applied in the form of BMP-NP, treatment of neuroinflammatory disease in mice exclusively depended on the control of macrophage function whereas effects on T cells and brain endothelial cells were dispensable for therapeutic efficacy. Importantly, BMP-NP were not only active in mice but also showed strong activity towards monocytes isolated from healthy human volunteers. We conclude that application of GC via IOH-NP has the potential to improve MS therapy in the future.

Quality of life related to oral health is assessed through the individual’s self-perceived oral health (SPOH). The objective is to determine SPOH in relation to socio-demographic and health characteristics in older adults beneficiaries from the Instituto Mexicano del Seguro Social (IMSS) in Mexico City.Cross-sectional study. We used data collection with questionnaire and assessment scales related to socio-demographic, health and dependency variables, as well as the visit to the dentist, the use of removable dental prostheses and SPOH. The self-perception means (Geriatric/General Oral Health Assessment Index-GOHAI) were calculated, and we used Student’s t, ANOVA and Bonferroni post hoc tests.60.5% were women; the average age of population was 68.23 ± 7.0. GOHAI total mean was 48.07 (48.05-48.08). Compared to their counterparts, people with the next features showed marked improvement in SPOH: of 60-69 years of age, separated or divorced, ≥ 7 years of study, paid work, living alone, no smoking, drinking alcohol, with a good health perception, low weight, no cognitive impairment, no depression, no anxiety, no comorbidity, consumption5 drugs, with limitations in basic activities, without limitations in instrumental activities, who did not visit the dentist and who did not use removable prosthesis.The concept of quality of life essentially incorporates the SPOH as a need in the evaluation of health outcomes.la calidad de vida relacionada con la salud oral se evalúa a partir de la autopercepción de la salud oral (APSO) del individuo. El objetivo es determinar la APSO con respecto a las características sociodemográficas y de salud en adultos mayores derechohabientes del Instituto Mexicano del Seguro Social (IMSS) de la Ciudad de México.estudio transversal con datos sociodemográficos, de salud, de dependencia, visita al dentista, uso de prótesis dental removible y APSO. Se calcularon las medias de autopercepción (Geriatric/General Oral Health Assessment Index: GOHAI) y se usaron las pruebas t de Student, ANOVA y post hoc Bonferroni.el 60.5% fueron mujeres. La edad promedio de la población fue 68.23 ± 7.0. La media (IC) del GOHAI total fue 48.07 (48.05-48.08). Comparados con sus contrapartes, hubo mejor autopercepción de la salud oral en los individuos del grupo de 60-69 años, separados o divorciados, ≥ 7 años de estudio, con trabajo remunerado, que vivían solos, no fumaban, sí bebían alcohol, tenían buena percepción de salud, bajo peso, sin deterioro cognitivo, ni depresión, ni ansiedad, ni comorbilidades, que consumían5 fármacos, con limitaciones en actividades básicas, sin limitaciones en actividades instrumentales, que no visitaban al dentista y no usaban prótesis removible.el concepto de calidad de vida incorpora esencialmente la APSO del paciente como una necesidad en la evaluación de resultados en salud.

The field of ecological restoration (ER) is now challenged by the need to achieve recovery at large spatial scales. Such scaling up requires technological expertise, inclusiveness and clarity of goals, and correct governance schemes and monitoring protocols, which are often absent from ER projects in most countries. We analyze the case of Colombia by assessing the planning, governance, and monitoring practices of 119 ER projects, and discuss them in the context of scaling up efforts to meet international commitments. In a top-down approach, Colombia´s government is the biggest ER driver: setting up the necessary policy framework to promote ER, and initiating 64% and fully financing 78% of the projects in the country. However, projects lack depth in participatory governance and adequate planning and monitoring, limiting their potential for sustainability and knowledge sharing, both of which are necessary for scaling up. We propose three areas for improvement in order to scale-up and meet international ER targets in Colombia, as well as in other Latin American countries, such as Mexico, Chile, and Argentina, which are also in the process of consolidating a large-scale ER vision. The benefits of some of those improvements have already been demonstrated in Brazil.

"la calidad de vida relacionada con la salud oral se evalúa a partir de la autopercepción de la salud oral (APSO) del individuo. El objetivo es determinar la APSO con respecto a las características sociodemográficas y de salud en adultos mayores derechohabientes del Instituto Mexicano del Seguro Social (IMSS) de la Ciudad de México. Métodos: estudio transversal con datos sociodemográficos, de salud, de dependencia, visita al dentista, uso de prótesis dental removible y APSO. Se calcularon las medias de autopercepción (Geriatric/General Oral Health Assessment Index: GOHAI) y se usaron las pruebas t de Student, ANOVA y post hoc Bonferroni. Resultados: el 60.5% fueron mujeres. La edad promedio de la población fue 68.23 ± 7.0. La media (IC) del GOHAI total fue 48.07 (48.05-48.08). Comparados con sus contrapartes, hubo mejor autopercepción de la salud oral en los individuos del grupo de 60-69 años, separados o divorciados, ≥ 7 años de estudio, con trabajo remunerado, que vivían solos, no fumaban, sí bebían alcohol, tenían buena percepción de salud, bajo peso, sin deterioro cognitivo, ni depresión, ni ansiedad, ni comorbilidades, que consumían < 5 fármacos, con limitaciones en actividades básicas, sin limitaciones en actividades instrumentales, que no visitaban al dentista y no usaban prótesis removible. Conclusión: el concepto de calidad de vida incorpora esencialmente la APSO del paciente como una necesidad en la evaluación de resultados en salud."

Glucocorticoids (GCs) are released from the adrenal gland during inflammation and help to keep immune responses at bay. Owing to their potent anti-inflammatory activity, GCs also play a key role in controlling acute graft-versus-host disease (aGvHD). Here we demonstrate that mice lacking the glucocorticoid receptor (GR) in T cells develop fulminant disease after allogeneic bone marrow transplantation. In a fully MHC-mismatched model, transfer of GR-deficient T cells resulted in severe aGvHD symptoms and strongly decreased survival times. Histopathological features were aggravated and infiltration of CD8(+) T cells into the jejunum was increased when the GR was not expressed. Furthermore, serum levels of IL-2, IFNγ, and IL-17 were elevated and the cytotoxicity of CD8(+) T cells was enhanced after transfer of GR-deficient T cells. Short-term treatment with dexamethasone reduced cytokine secretion but neither impacted disease severity nor the CTLs' cytolytic capacity. Importantly, in an aGvHD model in which disease development exclusively depends on the presence of CD8(+) T cells in the transplant, transfer of GR-deficient T cells aggravated clinical symptoms and reduced survival times as well. Taken together, our findings highlight that suppression of CD8(+) T-cell function is a crucial mechanism in the control of aGvHD by endogenous GCs.

El cultivo del cacao (Theobroma cacao), en épocas precolombinas, fue de importancia económica y cultural en El Salvador; pero debido a las inclemencias del tiempo sobre la población nativa, parte del conocimiento sobre el cultivo del cacao se perdió. En la actualidad se pretende reactivar los campos de cacao en algunas fincas del país, ya que muchos de los bosques cafetaleros se deterioraron por causa de la Roya, enfermedad provocada por el hongo Hemileia vastatrix. Debido a este problema, se decidió implementar un sistema de micropropagación de árboles de cacao nativos de El Salvador para establecer un protocolo de rescate de materiales autóctonos; y posteriormente, facilitar la propagación mediante la técnica de embriogénesis somática. En este ensayo se evaluaron tres dosis de glucosa, siendo 10, 20 y 30g L-1, como fuente de carbón en el medio de cultivo, y cuatro dosis de 2-4D (Ácido 2-4 diclorofenoxiacético), siendo 0.0, 1.0, ,2.0 y 3.0ml L-1; esta auxina interviene en la callogénesis de los explantes de cacao. El medio de cultivo utilizado fue DKW (Driver y Kiniyuki et al., 1984). El mejor tratamiento para la regeneración de callos se obtuvo con la dosis de 20g L-1 de glucosa y 2.0ml L-1 de 2-4D. Se realizó un Análisis de Varianza (ANOVA) con comparación de medias por Tukey y Test de Rangos Múltiples; además se empleó el programa estadístico Statgraphics Centurion XVI.I para el análisis de los datos.Producción Agropecuaria y Desarrollo Sostenible, Vol. 6, 2017: 87-95

espanolEn la clarificacion del agua potable se utilizan productos quimicos como el sulfato de aluminio para remover materia coloidal y sustancias organicas, mejorando la calidad del agua. Elevadas concentraciones de aluminio residual en el agua potable tienen implicaciones en la salud humana, siendo necesario el desarrollo de coagulantes alternativos, ambientalmente aceptables para reemplazarlos. En esta investigacion se evaluaron las propiedades que tiene la tuna opuntia ficus-indica y el alumbre en la clarificacion de las aguas del rio Magdalena en Magangue, Departamento de Bolivar (Colombia); como coagulante. Finalmente, se demostro la eficiencia que tiene el mucilago extraido de la tuna opuntia ficus-indica como coagulante natural. En aguas poco turbias como esta, la velocidad de agitacion tiene incidencia en la accion del clarificante, ya que este logra llegar hasta las particulas mas dispersas aumentando la eficiencia del proceso de clarificacion. EnglishIn the clarification of the potable water chemicals like aluminum sulphate is use to remove colloidal matter and organic substances, improving the quality of the water. High residual aluminum concentrations in the potable water have implications in the human health, being necessary the alternative coagulants development, environmentally acceptable to replace them. In this investigation the properties that have the cactus Opuntia ficus-indica and alum in the water clarification of the Magdalena River in Magangue, Bolivar province (Colombia), as coagulant were evaluated. Finally, the efficiency that has mucilage extracted of the cactus Opuntia ficus-indica as natural coagulant was shown. In low-turbidity water like this, the agitation speed has an impact on the action clearer because this achieves reach the more dispersed particles increasing the efficiency of the clarification process.

The correction of severe spinal deformities by an isolated posterior approach often involves cord manipulation together with hypotensive anesthesia. To date, the efficiency of methods to increase the tolerance of the cord to displacement and the influence of hypotension on this tolerance is yet to be assessed.The objective of this study was to determine the limits of cord displacement before the disappearance of neurophysiologic signals. The influence of the type of force applied, the section of the roots, and the induced hypotension on the cord's tolerance to displacement was also assessed.Experimental study using a domestic pig model.Successive records of cord-to-cord motor evoked potentials were obtained during displacement maneuvers. Displacing forces were released immediately after the absence of neurophysiologic signals.Surgical procedures were performed under conventional general anesthesia. The spinal cord and nerve roots from T6 to T10 levels were exposed by excision of the posterior elements, allowing for free cord movement. Three groups were established according to the method of spinal cord displacement: the separation (Group 1, n=5), the root stump pull (Group 2, n=5), and the torsion groups (Group 3, n=5). An electromechanical external device was used to apply the displacing forces. The three displacement tests were repeated after sectioning the adjacent nerve roots. The experiments were first carried out under normotension and afterward under induced hypotension.In Group 1, evoked potential disappeared with a displacement of 10.1±1.6 mm with unharmed roots and 15.3±4.7 mm after the sectioning of four adjacent roots (p.01). After induced hypotension, potentials were lost at 4.0±1.2 mm (p.01). In Group 2, the absence of potentials occurred at 20.0±4.3 mm and increased to 23.5±2.1 mm (p.05) after cutting the two contralateral roots. Under hypotensive conditions, the loss of neurophysiologic signals was detected at 5.3±1.2 mm (p.01). In Group 3, the cord allowed torsion of 95.3±.2° that increased to 112.4±7.1° if the contralateral roots were cut. Under hypotension, the loss of potentials was found at 20±6.2° (p.01).In this experimental model, it was possible to displace the thoracic spinal cord by a distance superior to the spinal cord width without suffering neurophysiologic changes. The limits of cord displacement increase when the adjacent nerve roots are sacrificed. Induced hypotension had a dramatic effect on the tolerance of the spinal cord for displacement. This work has an important clinical significance because induced hypotension during specific spine surgery procedures requiring spinal cord manipulation in humans may increase the risk of neurologic spinal cord injury.

To evaluate the degree of acute or progressive lateral compression needed to cause neurologic injury to the spinal cord assessed by electrophysiological monitoring. In five domestic pigs, the spinal cord was exposed and compressed between T8-T9 roots using a precise compression device. Two sticks placed on both sides of the spinal cord were sequentially brought together (0.5 mm every 2 min), causing progressive spinal cord compression. Acute compression was reproduced by a 2.5-mm displacement of the sticks. Cord-to-cord evoked potentials were obtained with two epidural catheters. Increasing latency and decreasing amplitude of the evoked potentials were observed after a mean progressive displacement of the sticks of 3.2 +/- 0.9 mm, disappearing after a mean displacement of 4.6 +/- 1.2 mm. The potential returned after compression removal (16.8 +/- 3.2 min). The potentials disappeared immediately after an acute compression of 2.5 +/- 0.3 mm, without any sign of recovering after 30 min. The experimental model replicates the mechanism of a spinal cord injury caused by medially displaced screws into the spinal canal. The spinal cord had more ability for adaptation to progressive and slow compression than to acute mechanisms.

Este estudio se basa en la importancia que tienen las musáceas de guineo dátil (AA) y manzano (AAB) en la dieta salvadoreña, así como su relevancia económica, social y nostálgica para el país. El propósito del experimento fue desarrollar un protocolo eficiente para reproducir estas especies en laboratorio, para luego entregarlas a pequeños productores agrícolas de dos cooperativas nacionales. El proceso se compuso de cinco diferentes fases: establecimiento, multiplicación, desarrollo, enraizamiento y aclimatación de las especies. El ensayo se realizó bajo condiciones controladas dentro de un laboratorio, en donde se obtuvieron los hijos de espada que sirvieron como fuente de semilla. Los cormos se redujeron y lavaron con Tween 80. Cada muestra se desinfectó con lejía pura (hipoclorito de sodio al 5.25%). Los meristemas extraídos de los cormos fueron colocados en un medio de cultivo nutritivo MS (Murashige & Skoog, 1962), conteniendo 5.0 mg/1 de la citoquinina BAP (Bencilaminopurina) y un pH de 5.8. En ambos casos la respuesta de las muestras fue similar con respecto las condiciones in vitro.En un inicio el guineo manzano respondió mejor a la multiplicación, pero la oxidación limitó en gran medida la obtención de una mayor cantidad de explantes de esta variedad. Este fenómeno se controló con la aplicación de I25mg/l de ácido ascórbico al cultivo. Al final de los diez ciclos de multiplicación se obtuvieron 2,500 plantas de cada especie. Éstas fueron enraizadas, aclimatadas y entregadas a dos cooperativas de pequeños productores nacionales.Producción Agropecuaria y Desarrollo Sostenible, Vol. 1, 2012: 33-46

Present studies concerning the safety and reliability of neurophysiological monitoring during thoracic pedicle screw placement remain inconclusive, and therefore, universally validated threshold levels that confirm osseous breakage of the instrumented pedicles have not been properly established.The objective of this work was to analyze whether electromyographic (EMG) thresholds, after stimulation of the thoracic pedicle screw, depend on the distance between the neural structures and the screws. The modifier effect of different interposed tissues between a breached pedicle and neural structures was also investigated.This experimental study uses a domestic pig model.Electromyographic thresholds were recorded after the stimulation of 18 thoracic pedicle screws that had been inserted into five experimental animals using varying distances between each screw and the spinal cord (8 and 2 mm). Electromyographic thresholds were also registered after the medial pedicle cortex was broken and after different biological tissues were interposed (blood, muscle, fat, and bone) between the screw and the spinal cord.Mean EMG thresholds increased to 14.1±5.5 mA for screws with pedicle cortex integrity that were placed 8 mm away from the dural sac. After the medial pedicle cortex was broken and without varying the distance of the screw to the dural sac, the mean EMG thresholds were not appreciably changed (13.6±6.3 mA). After repositioning the screw at a distance of 2 mm from the spinal cord and after medial cortical breach of the pedicle, the mean threshold significantly slowed to 7.4±3.4 mA (p.001). When the screw was placed in contact with the spinal dural sac, even lower EMG thresholds were registered (4.9±1.9, p.001). Medial pedicle cortex rupture and the interposition of different biological tissues in experimental animals did not alter the stimulation thresholds of the thoracic pedicle screws.In the experimental animals, the observed electrical impedance depended on the distance of screws from the neural structures and not on the integrity of the pedicle cortex. The screw-triggered EMG technique did not reliably discriminate the presence or absence of bone integrity after pedicle screw placement. The response intensity was not related to the type of interposed tissue.

This study was aimed at evaluating the sensitivity and safety of a new technique to record triggered EMG thresholds from axillary chest wall electrodes when inserting pedicle screws in the upper thoracic spine (T2–T6). A total of 248 (36.6%) of a total of 677 thoracic screws were placed at the T2–T6 levels in 92 patients with adolescent idiopathic scoliosis. A single electrode placed at the axillary midline was able to record potentials during surgery from all T2–T6 myotomes at each side. Eleven screws were removed during surgery because of malposition according to intraoperative fluoroscopic views. Screw position was evaluated after surgery in the remaining 237 screws using a CT scan. Malposition was detected in 35 pedicle screws (14.7%). Pedicle medial cortex was breached in 24 (10.1%). Six screws (2.5%) were located inside the spinal canal. Mean EMG threshold was 24.44 ± 11.30 mA in well-positioned screws, 17.98 ± 8.24 mA (p

The effects of 1-MCP and CA storage in aroma production and consumer acceptance, were investigated during the long-term storage of ‘Packham‘s Triumph’ pears. Pears were harvested 144 (Harvest 1) and 157 days (Harvest 2) after full bloom. The fruit were stored under cold storage (0 °C, 90–95% R.H.), controlled atmospheres (CA, 2.0–2.5 kPa O 2 and 1.0–1.5 kPa CO 2 ) or treated at harvest with 1-MCP (0.2 μL L −1 ) followed by cold storage. Ripening indices and aroma volatile production (using SPME technology) were determined after 2, 4 and 6 months of storage plus 5 days of shelf life, in addition to sensory evaluations. Butyl and hexyl acetate, followed by pentyl acetate and butyl butanoate, were the most abundant esters produced by the pears, and butanol and hexanol the most abundant alcohols. Their abundance increased during the development of ripening. Hexyl acetate with fruity notes was found to be the main contributor to the aroma of the pears, followed by butyl acetate and pentyl acetate, while alcohols showed a poor contribution. After 2 months of storage, pears stored under regular cold storage developed the highest content of volatile compounds and also the highest odour value, being preferred by sensory panelists. CA storage and 1-MCP treatment reduced the production of aromatic volatiles by the fruit. Nevertheless, after a longer storage period, pears treated with 1-MCP or stored under CA conditions, recovered capacity for volatile production with odour activity, and the panelists preferred 1-MCP treated over CA stored fruit. Pears treated with 1-MCP from the late harvest date were capable of producing higher amounts of volatile compounds during storage than those harvested at the commercial peak. The treatment of pears with 1-MCP followed by cold storage maintained textural characteristics preferred by the consumers and the capacity of volatile production, and therefore this technology could be used for maintaining fruit quality during long-term storage.

Glucocorticoids (GCs) are released from the adrenal gland during inflammation and help to keep immune responses at bay. Owing to their potent anti-inflammatory activity, GCs also play a key role in controlling acute graft-versus-host disease (aGvHD). Here we demonstrate that mice lacking the glucocorticoid receptor (GR) in T cells develop fulminant disease after allogeneic bone marrow transplantation. In a fully MHC-mismatched model, transfer of GR-deficient T cells resulted in severe aGvHD symptoms and strongly decreased survival times. Histopathological features were aggravated and infiltration of CD8(+) T cells into the jejunum was increased when the GR was not expressed. Furthermore, serum levels of IL-2, IFNγ, and IL-17 were elevated and the cytotoxicity of CD8(+) T cells was enhanced after transfer of GR-deficient T cells. Short-term treatment with dexamethasone reduced cytokine secretion but neither impacted disease severity nor the CTLs' cytolytic capacity. Importantly, in an aGvHD model in which disease development exclusively depends on the presence of CD8(+) T cells in the transplant, transfer of GR-deficient T cells aggravated clinical symptoms and reduced survival times as well. Taken together, our findings highlight that suppression of CD8(+) T-cell function is a crucial mechanism in the control of aGvHD by endogenous GCs.

I norsk akademia later det til å råde en oppfatning om at litteraturhistoriske fremstillinger ligner på hverandre. Dette er noe som blir hevdet i litteraturhistoriske artikler så vel som i verk. Jeg har hatt til intensjon å undersøke om oppfatningen stemmer ved å undersøke utvalgte norske litteraturhistoriske fremstillinger av Camilla Collett. Målet for undersøkelsene har vært å finne ut om det er grunnlag for å hevde at litteraturhistoriske fremstillinger ligner på hverandre samt å kartlegge et bilde av hvordan den litteraturhistoriografiske formidlingen foregår i norske verk. Oppgaven er en komparativ undersøkelse der hver litteraturhistoriske fremstilling sammenlignes med både den første utfyllende fremstillingen av Camilla Collett og med hverandre. I tillegg tas det hensyn til hva Camilla Collett selv mente om den første portretteringen. De litteraturhistoriske fremstillingene som er undersøkt er hovedsakelig valgt på grunn av deres betydning i akademia. Utvalget strekker seg fra 1862 til 2006, og det er til sammen 11 litteraturhistorier som blir undersøkt. Resultatene av undersøkelsene viser at det faktisk er slik at flere litteraturhistorier bærer mange av de samme trekkene. Det er også flere som ser ut til å ha trekk fra den første litteraturhistoriske fremstillingen som ble skrevet om Camilla Collett. Imidlertid er det hovedsakelig de historisk-biografiske litteraturhistoriene dette gjelder. Litteraturhistorier som har gått mer bort fra den biografiske formen, er også tonet ned i forhold til momenter som kan ligne foregående litteraturhistorier, noe som i hovedsak vil si historisk-biografiske trekk. Likevel kan man også spore noen likheter mellom ulike typer litteraturhistorier.

STUDY DESIGN A cross-sectional study of nonconsecutive cases (level III evidence). OBJECTIVE In a series of young patients with thoracic scoliosis who were treated with pedicle screw constructs, data obtained from triggered electromyography (t-EMG) screw stimulation and postoperative computed tomographic scans were matched to find different threshold limits for the safe placement of pedicle screws at the concavity (CC) and convexity (CV) of the scoliotic curves. The influence of the distance from the medial pedicle cortex to the spinal cord on t-EMG threshold intensity was also investigated at the apex segment. SUMMARY OF BACKGROUND DATA Whether the t-EMG stimulation threshold depends on pedicle bony integrity or on the distance to neural tissue remains elusive. Studying pedicle screws at the CC and CV at the apex segments of scoliotic curves is a good model to address this issue because the spinal cord is displaced to the CC in these patients. METHODS A total of 23 patients who underwent posterior fusions using 358 pedicle thoracic screws were reviewed. All patients presented main thoracic scoliosis, with a mean Cobb angle of 58.3 degrees (range, 46-87 degrees). Accuracy of the screw placement was tested at surgery by the t-EMG technique. During surgery, 8 screws placed at the CC showed t-EMG threshold values below 7 mA and were carefully removed. Another 25 screws disclosed stimulation thresholds within the range of 7 to 12 mA. After checking the screw positions by intraoperative fluoroscopy, 15 screws were removed because of clear signs of malpositioning. Every patient underwent a preoperative magnetic resonance imaging examination, in which the distances from the spinal cord to the pedicles of the concave and convex sides at 3 apex vertebrae were measured. Postoperative computed tomographic scans were used in all patients to detect screw malpositioning of the final 335 screws. RESULTS According to postoperative computed tomographic scans, 44 screws (13.1%) showed different malpositions: 40 screws (11.9%) perforated the medial pedicle wall, but only 11 screws (3.2%) were completely inside the spinal canal. If we considered the 23 screws removed during surgery, the true rate of misplaced screws increased to 18.7%. In those screws that preserved the pedicle cortex (well-positioned screws), EMG thresholds from the CC showed statistically significantly lower values than those registered at the CV of the deformity (21.1 ± 8.2 vs 23.9 ± 7.7 mA, P < 0.01). In the concave side, t-EMG threshold values under 8 mA should be unacceptable because they correspond to screw malpositioning. Threshold values above 14 mA indicate an accurate intrapedicular position with certainty. At the convex side, threshold values below 11 mA always indicate screw malpositioning, and values above 19 mA imply accurate screw placement. At the 3 apex vertebrae, the average pedicle-spinal cord distance was 2.2 ± 0.7 mm at the concave side and 9.8 ± 4.3 mm at the convex side (P < 0.001). In well-positioned screws, a correlation between pedicle-dural sac distance and t-EMG threshold values was found at the concave side only (Pearson r = 0.467, P < 0.05). None of the patients with misplaced screws showed postoperative neurological impairment. CONCLUSION Independent of the screw position, average t-EMG thresholds were always higher at the CV in the apex and above the apex regions, presuming that the distance from the pedicle to the spinal cord plays an important role in electrical transmission. The t-EMG technique has low sensitivity to predict screw malpositioning and cannot discriminate between medial cortex breakages and complete invasion of the spinal canal.