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OBJECTIVES: A feasibility proof-of-concept study was conducted to assess the effects of acute tibial nerve stimulation (TNS) on the central nervous system in healthy volunteers using functional magnetic resonance imaging (fMRI). MATERIALS AND METHODS: Fourteen healthy volunteers were included in a prospective, single-site study conducted on a clinical 3T MRI scanner. Four scans of functional MRI, each lasting 6 min, were acquired: two resting-state fMRI scans (prior and following the TNS intervention) and in-between two fMRI scans, both consisting of alternating rest periods and noninvasive acute transcutaneous TNS (TTNS). Whole brain seed-based functional connectivity (FC) correlation analysis was performed comparing TTNS stimulation with rest periods. Cluster-level familywise error (FWE) corrected p and a minimal cluster size of 200 voxels were used to explore FC patterns. RESULTS: Increased FC is reported between inferior frontal gyrus, posterior cingulate gyrus, and middle temporal gyrus with the precuneus as central receiving node. In addition, decreased FC in the cerebellum, hippocampus, and parahippocampal areas was observed. CONCLUSIONS: Altered FC is reported in areas which have been described to be also involved in lower urinary tract control. Although conducted with healthy controls, the assumption that the underlying therapeutic effect of TNS involves the central nervous system is supported and has to be further examined in patients with incomplete spinal cord injury.
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Encéfalo , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Estudios Prospectivos , Mapeo Encefálico/métodos , Nervio Tibial/diagnóstico por imagenRESUMEN
Diffusion kurtosis imaging (DKI) is applied to gain insights into the microstructural organization of brain tissues. However, the reproducibility of DKI outside brain white matter, particularly in combination with advanced estimation to remedy its noise sensitivity, remains poorly characterized. Therefore, in this study, we investigated the variability and reliability of DKI metrics while correcting implausible values with a fit method called mean kurtosis (MK)-Curve. A total of 10 volunteers (four women; age: 41.4 ± 9.6 years) were included and underwent two MRI examinations of the brain. The images were acquired on a clinical 3-T scanner and included a T1-weighted image and a diffusion sequence with multiple diffusion weightings suitable for DKI. Region of interest analysis of common kurtosis and tensor metrics derived with the MK-Curve DKI fit was performed, including intraclass correlation (ICC) and Bland-Altman (BA) plot statistics. A p value of less than 0.05 was considered statistically significant. The analyses showed good to excellent agreement of both kurtosis tensor- and diffusion tensor-derived MK-Curve-corrected metrics (ICC values: 0.77-0.98 and 0.87-0.98, respectively), with the exception of two DKI-derived metrics (axial kurtosis in the cortex: ICC = 0.68, and radial kurtosis in deep gray matter: ICC = 0.544). Non-MK-Curve-corrected kurtosis tensor-derived metrics ranged from 0.01 to 0.52 and diffusion tensor-derived metrics from 0.06 to 0.66, indicating poor to moderate reliability. No structural bias was observed in the BA plots for any of the diffusion metrics. In conclusion, MK-Curve-corrected DKI metrics of the human brain can be reliably acquired in white and gray matter at 3 T and DKI metrics have good to excellent agreement in a test-retest setting.
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Imagen de Difusión Tensora , Sustancia Blanca , Humanos , Femenino , Adulto , Persona de Mediana Edad , Reproducibilidad de los Resultados , Imagen de Difusión Tensora/métodos , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Sustancia Blanca/diagnóstico por imagen , Imagen de Difusión por Resonancia MagnéticaRESUMEN
BACKGROUND: Spinal epidural hematoma without significant trauma is a rare condition with potentially severe outcome. This case report and systematic review of the literature illustrates the clinical presentation, risk factors, evaluation, treatment and outcomes of spinal epidural hematoma without significant trauma in children. CASE PRESENTATION: We report one case of a 7-year-old girl who developed a neck pain after minor cervical sprain. MRI showed a right posterior epidural hematoma extending from C2/3 to T1. The hematoma was surgically evacuated, and the histopathology showed an arteriovenous malformation. Postoperative MRI showed complete evacuation of the hematoma and no residual vascular malformation. We report a second ASE with idiopathic spinal epidural hematoma of a 4½-year-old boy presenting with neck pain. MRI showed a right-sided latero-posterior subacute spinal epidural hematoma at C3-C5. Owing to the absence of any neurological deficit, the patient was treated conservatively. MRI at 3 months showed complete resolution of the hematoma. CONCLUSIONS: Spinal epidural hematoma without significant trauma in children is a rare condition. It may present with unspecific symptoms. Screening for bleeding diathesis is warranted and neuroradiologic follow-up is essential to rule out vascular malformation. Whereas most children have a favorable outcome, some do not recover, and neurological follow-up is required.
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Malformaciones Arteriovenosas , Hematoma Espinal Epidural , Malformaciones Arteriovenosas/complicaciones , Niño , Preescolar , Femenino , Hematoma Espinal Epidural/diagnóstico por imagen , Hematoma Espinal Epidural/etiología , Humanos , Imagen por Resonancia Magnética , Masculino , Dolor de Cuello/etiologíaRESUMEN
Cerebral oximetry using near-infrared spectroscopy (NIRS) allows for continuous monitoring of cerebral perfusion and immediate treatment of hemodynamic perturbations. In configurations used in current clinical practice, NIRS optodes are placed on the patient`s forehead and cerebral oxygen saturation (ScO2 ) is determined in bilateral frontal cortical samples. However, focal cerebral ischemic lesions outside of the NIRS field of view may remain undetected. The objective of this observational case-series study was to investigate ScO2 measurements in patients with acute iatrogenic stroke not located in the frontal cortical region. Adult patients undergoing cardiac surgery with cardiopulmonary bypass or interventional cardiology procedures and suffering stroke in the early postoperative period were identified from the Bernese Stroke Registry and analyzed for their intraoperative ScO2 values and brain imaging data. Main outcome measures were the ScO2 values, computed tomography and magnetic resonance imaging findings. In six patients, the infarct areas were localized in the vascular territories of the posterior and/or dorsal middle cerebral arteries. One patient had watershed stroke and another one excellent collaterals resulting in normal cerebral blood volume and only subtle decrease of cerebral blood flow in initially critically perfused watershed brain areas. Intraoperative ScO2 values were entirely unremarkable or nonindicative for brain damage. Our results indicate that uneventful intraoperative NIRS monitoring does not exclude severe cerebral ischemia due to the limited field of view of commercially available NIRS devices. False negative NIRS may occur as a consequence of stroke localized outside the frontal cortex.
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Isquemia Encefálica/diagnóstico , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Monitoreo Intraoperatorio/métodos , Oximetría/métodos , Complicaciones Posoperatorias/diagnóstico , Espectroscopía Infrarroja Corta/métodos , Adulto , Anciano , Anciano de 80 o más Años , Encéfalo/irrigación sanguínea , Isquemia Encefálica/etiología , Puente Cardiopulmonar/métodos , Infarto Cerebral/diagnóstico , Infarto Cerebral/etiología , Circulación Cerebrovascular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiologíaRESUMEN
INTRODUCTION: Diagnostic tools to show emboli reliably and protection techniques against embolization when employing stent retrievers are necessary to improve endovascular stroke therapy. The aim of the present study was to investigate iatrogenic emboli using susceptibility-weighted imaging (SWI) in an open series of patients who had been treated with stent retriever thrombectomy using emboli protection techniques. METHODS: Patients with anterior circulation stroke examined with MRI before and after stent retriever thrombectomy were assessed for iatrogenic embolic events. Thrombectomy was performed in flow arrest and under aspiration using a balloon-mounted guiding catheter, a distal access catheter, or both. RESULTS: In 13 of 57 patients (22.8%) post-interventional SWI sequences detected 16 microemboli. Three of them were associated with small ischemic lesions on diffusion-weighted imaging (DWI). None of the microemboli were located in a new vascular territory, none showed clinical signs, and all 13 patients have been rated as Thrombolysis in Cerebral Infarction (TICI) 2b (n = 3) or 3 (n = 10). Retrospective reevaluation of the digital subtraction angiography (DSA) detected discrete flow stagnation nearby the iatrogenic microemboli in four patients with a positive persistent collateral sign in one. CONCLUSION: Our study demonstrates two things: First, SWI seems to be more sensitive to detect emboli than DWI and DSA and, second, proximal or distal protected stent retriever thrombectomy seems to prevent iatrogenic embolization into new vascular territories during retraction of the thrombus, but not downstream during mobilization of the thrombus. Both techniques should be investigated and refined further.
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Embolia Intracraneal/prevención & control , Trombosis Intracraneal/patología , Trombosis Intracraneal/cirugía , Imagen por Resonancia Magnética/métodos , Trombolisis Mecánica/instrumentación , Stents , Anciano , Angiografía de Substracción Digital/métodos , Remoción de Dispositivos/instrumentación , Análisis de Falla de Equipo , Femenino , Humanos , Enfermedad Iatrogénica/prevención & control , Embolia Intracraneal/patología , Masculino , Persona de Mediana Edad , Pronóstico , Diseño de Prótesis , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: The aim of this prospective study was to assess vascular integrity after stent-retriever thrombectomy. METHODS: Dissection, contrast medium extravasation, and vasospasm were evaluated in 23 patients after thrombectomy with biplane or 3D-digital subtraction angiography and 3-Tesla vessel wall MRI. RESULTS: Vasospasm was detected angiographically in 10 patients, necessitating intra-arterial nimodipine in 2 of them. Contrast extravasation, intramural hemorrhage, or iatrogenic dissection were not detected on multimodal MRI in any patient even after Y-double stent-retriever technique. CONCLUSIONS: Our findings suggest that clinically relevant vessel wall injuries occur rarely after stent-retriever thrombectomy.
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Angiografía Cerebral , Arterias Cerebrales/diagnóstico por imagen , Imagen por Resonancia Magnética , Stents , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Angiografía Cerebral/métodos , Estudios de Cohortes , Humanos , Imagen por Resonancia Magnética/métodos , Estudios Prospectivos , Stents/efectos adversos , Accidente Cerebrovascular/diagnóstico por imagen , Trombectomía/efectos adversos , Resultado del Tratamiento , Vasoespasmo Intracraneal/diagnóstico por imagen , Vasoespasmo Intracraneal/etiologíaRESUMEN
OBJECTIVES: Susceptibility-weighted imaging (SWI) enables visualization of thrombotic material in acute ischemic stroke. We aimed to validate the accuracy of thrombus depiction on SWI compared to time-of-flight MRA (TOF-MRA), first-pass gadolinium-enhanced MRA (GE-MRA) and digital subtraction angiography (DSA). Furthermore, we analysed the impact of thrombus length on reperfusion success with endovascular therapy. METHODS: Consecutive patients with acute ischemic stroke due to middle cerebral artery (MCA) occlusions undergoing endovascular recanalization were screened. Only patients with a pretreatment SWI were included. Thrombus visibility and location on SWI were compared to those on TOF-MRA, GE-MRA and DSA. The association between thrombus length on SWI and reperfusion success was studied. RESULTS: Eighty-four of the 88 patients included (95.5%) showed an MCA thrombus on SWI. Strong correlations between thrombus location on SWI and that on TOF-MRA (Pearson's correlation coefficient 0.918, P < 0.001), GE-MRA (0.887, P < 0.001) and DSA (0.841, P < 0.001) were observed. Successful reperfusion was not significantly related to thrombus length on SWI (P = 0.153; binary logistic regression). CONCLUSIONS: In MCA occlusion thrombus location as seen on SWI correlates well with angiographic findings. In contrast to intravenous thrombolysis, thrombus length appears to have no impact on reperfusion success of endovascular therapy. KEY POINTS: ⢠SWI helps in assessing location and length of thrombi in the MCA ⢠SWI, MRA and DSA are equivalent in detecting the MCA occlusion site ⢠SWI is superior in identifying the distal end of the thrombus ⢠Stent retrievers should be deployed over the distal thrombus end ⢠Thrombus length did not affect success of endovascular reperfusion guided by SWI.
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Procedimientos Endovasculares , Infarto de la Arteria Cerebral Media/diagnóstico , Angiografía por Resonancia Magnética/métodos , Stents , Accidente Cerebrovascular/diagnóstico , Trombosis/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital/métodos , Femenino , Estudios de Seguimiento , Humanos , Infarto de la Arteria Cerebral Media/complicaciones , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Accidente Cerebrovascular/etiología , Trombosis/complicaciones , Adulto JovenRESUMEN
OBJECTIVE: To investigate pathological findings in the susceptibility weighted imaging (SWI) of patients experiencing convulsive (CSE) or non-convulsive status epilepticus (NCSE) with focal hyperperfusion in the acute setting. METHODS: Twelve patients (six with NCSE confirmed by electroencephalogram (EEG) and six patients with CSE with seizure event clinically diagnosed) underwent MRI in this acute setting (mean time between onset of symptoms and MRI was 3 h 8 min), including SWI, dynamic susceptibility contrast MR imaging (DSC) and diffusion-weighted imaging (DWI). MRI sequences were retrospectively evaluated and compared with EEG findings (10/12 patients), and clinical symptoms. RESULTS: Twelve out of 12 (100 %) patients showed a focal parenchymal area with pseudo-narrowed cortical veins on SWI, associated with focal hyperperfused areas (increased cerebral blood flow (CBF) and mean transit time (MTT) shortening), and cortical DWI restriction in 6/12 patients (50 %). Additionally, these areas were associated with ictal or postical EEG patterns in 8/10 patients (80 %). Most frequent acute clinical findings were aphasia and/or hemiparesis in eight patients, and all of them showed pseudo-narrowed veins in those parenchymal areas responsible for these symptoms. CONCLUSION: In this study series with CSE and NCSE patients, SWI showed focally pseudo-narrowed cortical veins in hyperperfused and ictal parenchymal areas. Therefore, SWI might have the potential to identify an ictal region in CSE/NCSE. KEY POINTS: ⢠The focal ictal brain regions show hyperperfusion in DSC MR-perfusion imaging. ⢠SWI shows focally diminished cortical veins in hyperperfused ictal regions. ⢠SWI has the potential to identify a focal ictal region in CSE/NCSE.
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Imagen de Difusión por Resonancia Magnética/métodos , Hemodinámica/fisiología , Estado Epiléptico/fisiopatología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Encéfalo/patología , Circulación Cerebrovascular , Niño , Preescolar , Electroencefalografía , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Flujo Sanguíneo Regional , Estudios Retrospectivos , Estado Epiléptico/diagnóstico , Adulto JovenRESUMEN
The present study aims at investigating the effect of interaction between the process parameters of each weld pass (1st pass and 2nd pass) to improve the joint performance during the double-sided friction stir welded joints of AA6061-T6 aluminium alloy. Experimental designs were conducted following a design matrix developed using response surface methodology to investigate the impact on the microstructural changes and tensile properties. Pronounced interaction between the process parameters of each weld pass of the joint was observed and indicated a strong interdependency between them. The detailed microstructural study conducted through EBSD insights into the extent of homogenization, and abnormal grain refinement and reflects a vast transformation of low-angle grain boundaries into high-angle grain boundaries within the stir zone. The profound examination through scanning electron microscopy and transmission electron microscopy analysis validated the uniform homogeneous distribution of Al-Fe and Al-Si-rich precipitates. The significant improvement in the grain refinement and distribution of the strengthening precipitates within the stir zone led to a substantial enhancement in the microhardness, along with achieving a maximum ultimate tensile strength of 223 MPa and a percentage elongation of 14%. A study of the fracture morphology ensures the ductile fracture behavior of the tensile fracture specimen by observing the presence of numerous dimples within a well-bonded joint.
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Addison's disease is known to cause hyperkalemia. However, heart block as a result of such hyperkalemia is very rare. We report one such case where Addison's disease presented with hyperkalemia and resultant heart block and Stokes-Adam's syndrome along with other features of hypoadrenalism.
RésuméLa maladie d'Addison est connue pour provoquer une hyperkaliémie. Cependant, un bloc cardiaque résultant d'une telle hyperkaliémie est très rare. Nous rapportons un cas dans lequel la maladie d'Addison s'est accompagnée d'une hyperkaliémie et d'un bloc cardiaque et du syndrome de Stokes-Adam ainsi que d'autres caractéristiques d'hyposurrénalisme.
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Hiperpotasemia , Humanos , Hiperpotasemia/diagnóstico , Hiperpotasemia/etiología , Hiperpotasemia/complicaciones , Masculino , Bloqueo Cardíaco/diagnóstico , Bloqueo Cardíaco/etiología , Insuficiencia Suprarrenal/diagnóstico , Insuficiencia Suprarrenal/complicaciones , Insuficiencia Suprarrenal/tratamiento farmacológico , Electrocardiografía , Resultado del Tratamiento , Enfermedad de Addison/complicaciones , Enfermedad de Addison/diagnóstico , Enfermedad de Addison/tratamiento farmacológico , Adulto , Femenino , SíndromeRESUMEN
The rising opportunities of sustainable tourism have brought many policies to control the exploitation of the environment and increase the reach of luxurious, safe, and authentic experiences to the different segments of tourists. This study seeks to prioritize the variables influencing the development of sustainable tourism and pinpoint key success factors that align with the Sustainable Development Goals (SDGs). It adopts a tri-dimensional framework encompassing economic, social, and environmental aspects, further delineated into eleven sub-dimensions, to provide a quantitative evaluation of sustainable tourism. We conducted interviews with 26 tourism industry experts hailing from eight countries, analyzing their responses using interval type-2 fuzzy sets. The results underscore the critical role of specific components in advancing sustainable tourism. In the economic dimension, "financial resources and tourism costs" emerge as vital factors. In the social dimension, "health and safety" takes center stage, while "green infrastructure" plays a pivotal role in the environmental dimension. These findings underscore the significance of these aspects in promoting sustainable tourism. Furthermore, this study explores the strategic importance of sustainable tourism equity in shaping tourism planning and development for emerging markets.
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Turismo , Unionidae , Animales , Desarrollo SostenibleRESUMEN
Background: The purpose of this study was to investigate the prevalence and distribution of different HCV genotypes, as well as to evaluate clinical and laboratory parameters in HCV-infected patients before and after DAA treatment. Material and Methods: An open-label prospective study was conducted on 50 HCV-infected individuals. The HCV-infected patients underwent a baseline evaluation with complete history, examination, and other clinical investigations. These patients received the appropriate DAA according to the genotype for 3 months. At the end of 3 months, these patients were again evaluated clinically. Results: The majority of instances were among younger age groups. Genotype 3 (66%) was the most common. There was a statistically significant difference found in clinical parameters regarding total bilirubin (p=0.008), SGOT (p=0.001), SGPT (p=0.035), ALP (p=<0.001) and Blood Urea Nitrogen (p = 0.004). When 1a vs 1b intragroup comparison was drawn, there was a significant mean difference found in SGOT (p value= 0.053) and Creatinine (p=0.050) parameters while rest shows no significant difference when associated. In the comparison of 1a vs 3 or 4, none of the parameters shows significant difference while; when 1b vs 3 or 4 comparison was laid out, SGOT and Creatinine was found near to significant. Conclusion: This study concludes that with the availability of DAAs, highly effective, short-duration, and safe regimens have created better outcomes for patients with HCV infection, especially in those groups where SVR was low with prior therapies or in those where IFN-based treatment strategies were contraindicated.
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The EOS™2D/3D system is a low-dose, 3D imaging system that utilizes two perpendicular X-ray beams to create simultaneous frontal and lateral images of the body. This is a useful modality to assess spinal pathologies. However, due to the slow imaging acquisition time up to 25 s, motion artifacts (MA) frequently occur. These artifacts may not be distinguishable from pathological findings, such as scoliosis, and may impair the diagnostic process. The aim of this study was to design a method to detect MA in EOS X-ray. We retrospectively analyzed EOS imaging from 40 patients wearing a radiopaque reference device during imaging. We drew a straight vertical line along the reference device. We measured deviations from it to quantify MA, presenting these findings through descriptive statistics. For a subset of patients with high MA, acquisitions were repeated after giving specific instructions to stand still. For these patients, we compared MA between the two acquisitions. In our study, a substantial proportion of patients exhibited MA ≥ 1 mm, with 80% in frontal projections and 87.9% in lateral projections. In the subjects who received a second acquisition, MA was significantly lower in the second images. Our method allows for a precise detection of MA on EOS images through a simple, yet reliable solution. Our method may improve the reliability of spine measurements, and reduce the risk of wrong diagnosis due to low imaging quality.
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Artefactos , Imagenología Tridimensional , Humanos , Rayos X , Estudios Retrospectivos , Reproducibilidad de los Resultados , Radiografía , Imagenología Tridimensional/métodosRESUMEN
A family of peptide signaling molecules (AtPeps) and their plasma membrane receptor AtPepR1 are known to act in pathogen-defense signaling cascades in plants. Little is currently known about the molecular mechanisms that link these signaling peptides and their receptor, a leucine-rich repeat receptor-like kinase, to downstream pathogen-defense responses. We identify some cellular activities of these molecules that provide the context for a model for their action in signaling cascades. AtPeps activate plasma membrane inwardly conducting Ca(2+) permeable channels in mesophyll cells, resulting in cytosolic Ca(2+) elevation. This activity is dependent on their receptor as well as a cyclic nucleotide-gated channel (CNGC2). We also show that the leucine-rich repeat receptor-like kinase receptor AtPepR1 has guanylyl cyclase activity, generating cGMP from GTP, and that cGMP can activate CNGC2-dependent cytosolic Ca(2+) elevation. AtPep-dependent expression of pathogen-defense genes (PDF1.2, MPK3, and WRKY33) is mediated by the Ca(2+) signaling pathway associated with AtPep peptides and their receptor. The work presented here indicates that extracellular AtPeps, which can act as danger-associated molecular patterns, signal by interaction with their receptor, AtPepR1, a plasma membrane protein that can generate cGMP. Downstream from AtPep and AtPepR1 in a signaling cascade, the cGMP-activated channel CNGC2 is involved in AtPep- and AtPepR1-dependent inward Ca(2+) conductance and resulting cytosolic Ca(2+) elevation. The signaling cascade initiated by AtPeps leads to expression of pathogen-defense genes in a Ca(2+)-dependent manner.
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Proteínas de Arabidopsis/fisiología , Arabidopsis/inmunología , Señalización del Calcio , Canales Catiónicos Regulados por Nucleótidos Cíclicos/fisiología , Receptores de Superficie Celular/fisiología , Transactivadores/fisiología , Proteínas de Arabidopsis/inmunología , Calcio/metabolismo , Canales Catiónicos Regulados por Nucleótidos Cíclicos/inmunología , Citosol , Guanilato Ciclasa/metabolismo , Inmunidad , Receptores de Superficie Celular/inmunología , Transactivadores/inmunologíaRESUMEN
OBJECTIVES: In spinal cord injury (SCI), the primary mechanical injury is followed by secondary sequelae that develop over the subsequent months and manifests in biochemical, functional, and microstructural alterations, at the site of direct injury but also in the spinal cord tissue above and below the actual lesion site. Noninvasive magnetic resonance spectroscopy (MRS) can be used to assess biochemical modulation occurring in the secondary injury phase, in addition to and supporting conventional MRI, and might help predict and improve patient outcome. In this article, we aimed to examine the metabolic levels in the pons of subacute SCI by means of in vivo proton MRS at 3 T and explore the association to clinical scores. MATERIALS AND METHODS: In this prospective study, between November 2015 and February 2018, single-voxel short-echo MRS data were acquired in healthy controls and in SCI subjects in the pons once during rehabilitation. Besides the single-point MRS examination, in addition, in participants with SCI, the clinical status (ie, motor, light touch, and pinprick scores) was assessed twice: (1) around the MRS session (approximately 10 weeks postinjury) and (2) before discharge (at approximately 9 months postinjury). The group differences were assessed with Kruskal-Wallis test, the post hoc comparison was assessed with Wilcoxon rank sum test, and the clinical correlations were conducted with Spearman rank correlation test. Bayes factor calculations completed the statistical part providing relevant evidence values. RESULTS: Twenty healthy controls (median age, 50 years; interquartile range, 41-55 years; 18 men) and 18 subjects with traumatic SCI (median age, 50 years; interquartile range, 32-58 years; 16 men) are included. Group comparison showed an increase of total N -acetylaspartate and combined glutamate and glutamine levels in complete SCI and a reduction of total creatine in incomplete paraplegic SCI. The proton MRS-based glutathione levels at baseline correlate to the motor score improvement during rehabilitation in incomplete subacute SCI. CONCLUSIONS: This exploratory study showed an association of the metabolite concentration of glutathione in the pons assessed at approximately 10 weeks after injury with the improvements of the motor score during the rehabilitation. Pontine glutathione levels in subjects with traumatic subacute incomplete SCI acquired remote from the injury site correlate to clinical score and might therefore be beneficial in the rehabilitation assessments.
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Protones , Traumatismos de la Médula Espinal , Masculino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Teorema de Bayes , Traumatismos de la Médula Espinal/diagnóstico por imagen , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/patología , Puente/diagnóstico por imagen , Puente/patologíaRESUMEN
The aim of this exploratory study was the assessment of the metabolic profiles of persons with complete spinal cord injury (SCI) in three region-of-interests (pons, cerebellar vermis, and cerebellar hemisphere), with magnetic resonance spectroscopy, and their correlations to clinical scores. Group differences and association between metabolic and clinical scores were examined. Fifteen people with chronic SCI (cSCI), five people with subacute SCI (sSCI) and fourteen healthy controls were included. Group comparison between cSCI and HC showed lower total N-acetyl-aspartate (tNAA) in the pons (p = 0.04) and higher glutathione (GSH) in the cerebellar vermis (p = 0.02). Choline levels in the cerebellar hemisphere were different between cSCI and HC (p = 0.02) and sSCI and HC (p = 0.02). A correlation was reported for choline containing compounds (tCho) to clinical scores in the pons (rho = - 0.55, p = 0.01). tNAA to total creatine (tNAA/tCr ratio) correlated to clinical scores in the cerebellar vermis (rho = 0.61, p = 0.004) and GSH correlated to the independence score in the cerebellar hemisphere (rho = 0.56, p = 0.01). The correlation of tNAA, tCr, tCho and GSH to clinical scores might be indicators on how well the CNS copes with the post-traumatic remodeling and might be further examined as outcome markers.
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Cerebelo , Traumatismos de la Médula Espinal , Humanos , Espectroscopía de Protones por Resonancia Magnética , Cerebelo/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Puente/diagnóstico por imagen , Puente/metabolismo , Creatina/metabolismo , Metaboloma , Colina/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Ácido Aspártico/metabolismoRESUMEN
The p53 tumor suppressor protein performs a number of cellular functions, ranging from the induction of cell cycle arrest and apoptosis to effects on DNA repair. Modulating p53 activity with Mdm2 inhibitors is a promising approach for treating cancer; however, it is presently unclear how the in vivo application of Mdm2 inhibitors impact the myriad processes orchestrated by p53. Since approximately half of all colon cancers (predominately cancers with microsatellite instability) are p53-normal, we assessed the anticancer activity of the Mdm2 inhibitor Nutlin-3 in the mouse azoxymethane (AOM) colon cancer model, in which p53 remains wild type. Using a cell line derived from an AOM-induced tumor, we found that four daily exposures to Nutlin-3 induced persistent p53 stabilization and cell cycle arrest without significant apoptosis. A 4-day dosing schedule in vivo generated a similar response in colon tumors; growth arrest without significantly increased apoptosis. In adjacent normal colon tissue, Nutlin-3 treatment reduced both cell proliferation and apoptosis. Surprisingly, Nutlin-3 induced a transient DNA damage response in tumors but not in adjacent normal tissue. Nutlin-3 likewise induced a transient DNA damage response in human colon cancer cells in a p53-dependent manner, and enhanced DNA strand breakage and cell death induced by doxorubicin. Our findings indicate that Mdm2 inhibitors not only trigger growth arrest, but may also stimulate p53's reported ability to slow homologous recombination repair. The potential impact of Nutlin-3 on DNA repair in tumors suggests that Mdm2 inhibitors may significantly accentuate the tumoricidal actions of certain therapeutic modalities.
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Neoplasias del Colon/metabolismo , Imidazoles/farmacología , Piperazinas/farmacología , Proteínas Proto-Oncogénicas c-mdm2/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Azoximetano/administración & dosificación , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/genética , Daño del ADN/efectos de los fármacos , Doxorrubicina/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HCT116 , Humanos , Ratones , Neoplasias Experimentales/inducido químicamente , Proteínas Proto-Oncogénicas c-mdm2/genética , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
PURPOSE: Although chronic pelvic pain syndrome impairs the life of millions of people worldwide, the exact pathomechanisms involved remain to be elucidated. As with other chronic pain syndromes, the central nervous system may have an important role in chronic pelvic pain syndrome. Thus, we assessed brain alterations associated with abnormal pain processing in patients with chronic pelvic pain syndrome. MATERIALS AND METHODS: Using brain morphology assessment applying structural magnetic resonance imaging, we prospectively investigated a consecutive series of 20 men with refractory chronic pelvic pain syndrome, and compared these patients to 20 gender and age matched healthy controls. Between group differences in relative gray matter volume and the association with bother of chronic pelvic pain syndrome were assessed using whole brain covariate analysis. RESULTS: Patients with chronic pelvic pain syndrome had a mean (± SD) age of 40 (± 14) years, a mean NIH-CPSI (National Institutes of Health Chronic Prostatitis Symptom Index) total score of 28 (± 6) and a mean pain subscale of 14 (± 3). In patients with chronic pelvic pain syndrome compared to healthy controls there was a significant reduction in relative gray matter volume in the anterior cingulate cortex of the dominant hemisphere. This finding correlated with the NIH-CPSI total score (r = 0.57) and pain subscale (r = 0.51). CONCLUSIONS: Reduction in relative gray matter volume in the anterior cingulate cortex and correlation with bother of chronic pelvic pain syndrome suggest an essential role for the anterior cingulate cortex in chronic pelvic pain syndrome. Since this area is a core structure of emotional pain processing, central pathomechanisms of chronic pelvic pain syndrome may be considered a promising therapeutic target and may explain the often unsatisfactory results of treatments focusing on peripheral dysfunction.
Asunto(s)
Giro del Cíngulo/patología , Dolor Pélvico , Prostatitis , Adulto , Anciano , Dolor Crónico , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Estudios Prospectivos , Adulto JovenRESUMEN
Ca(2+) influx is an early signal initiating cytosolic immune responses to pathogen perception in plant cells; molecular components linking pathogen recognition to Ca(2+) influx are not delineated. Work presented here provides insights into this biological system of non-self recognition and response activation. We have recently identified a cyclic nucleotide-activated ion channel as facilitating the Ca(2+) flux that initiates immune signaling in the plant cell cytosol. Work in this report shows that elevation of cAMP is a key player in this signaling cascade. We show that cytosolic Ca(2+) elevation, nitric oxide (NO) and reactive oxygen species generation, as well as immune signaling, lead to a hypersensitive response upon application of pathogens and/or conserved molecules that are components of microbes and are all dependent on cAMP generation. Exogenous cAMP leads to Ca(2+) channel-dependent cytosolic Ca(2+) elevation, NO generation, and defense response gene expression in the absence of the non-self pathogen signal. Inoculation of leaves with a bacterial pathogen leads to cAMP elevation coordinated with Ca(2+) rise. cAMP acts as a secondary messenger in plants; however, no specific protein has been heretofore identified as activated by cAMP in a manner associated with a signaling cascade in plants, as we report here. Our linkage of cAMP elevation in pathogen-inoculated plant leaves to Ca(2+) channels and immune signaling downstream from cytosolic Ca(2+) elevation provides a model for how non-self detection can be transduced to initiate the cascade of events in the cell cytosol that orchestrate pathogen defense responses.
Asunto(s)
Arabidopsis/inmunología , Calcio/metabolismo , AMP Cíclico/metabolismo , Transducción de Señal/inmunología , Adenilil Ciclasas/metabolismo , Arabidopsis/efectos de los fármacos , Arabidopsis/microbiología , Inhibidores Enzimáticos/farmacología , Lipopolisacáridos/farmacología , Óxido Nítrico/metabolismo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/inmunología , Hojas de la Planta/microbiología , Pseudomonas syringae/efectos de los fármacos , Pseudomonas syringae/inmunología , Receptores de Reconocimiento de Patrones/metabolismo , Transducción de Señal/efectos de los fármacosRESUMEN
Generating lineage-committed intestinal stem cells from embryonic stem cells (ESCs) could provide a tractable experimental system for understanding intestinal differentiation pathways and may ultimately provide cells for regenerating damaged intestinal tissue. We tested a two-step differentiation procedure in which ESCs were first cultured with activin A to favor formation of definitive endoderm, and then treated with fibroblast-conditioned medium with or without Wnt3A. The definitive endoderm expressed a number of genes associated with gut-tube development through mouse embryonic day 8.5 (Sox17, Foxa2, and Gata4 expressed and Id2 silent). The intestinal stem cell marker Lgr5 gene was also activated in the endodermal cells, whereas the Msi1, Ephb2, and Dcamkl1 intestinal stem cell markers were not. Exposure of the endoderm to fibroblast-conditioned medium with Wnt3A resulted in the activation of Id2, the remaining intestinal stem cell markers and the later gut markers Cdx2, Fabp2, and Muc2. Interestingly, genes associated with distal gut-associated mesoderm (Foxf2, Hlx, and Hoxd8) were also simulated by Wnt3A. The two-step differentiation protocol generated gut bodies with crypt-like structures that included regions of Lgr5-expressing proliferating cells and regions of cell differentiation. These gut bodies also had a smooth muscle component and some underwent peristaltic movement. The ability of the definitive endoderm to differentiate into intestinal epithelium was supported by the vivo engraftment of these cells into mouse colonic mucosa. These findings demonstrate that definitive endoderm derived from ESCs can carry out intestinal cell differentiation pathways and may provide cells to restore damaged intestinal tissue.