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1.
Nature ; 524(7565): 335-8, 2015 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-26289204

RESUMEN

Nearly three-quarters of the growth in global carbon emissions from the burning of fossil fuels and cement production between 2010 and 2012 occurred in China. Yet estimates of Chinese emissions remain subject to large uncertainty; inventories of China's total fossil fuel carbon emissions in 2008 differ by 0.3 gigatonnes of carbon, or 15 per cent. The primary sources of this uncertainty are conflicting estimates of energy consumption and emission factors, the latter being uncertain because of very few actual measurements representative of the mix of Chinese fuels. Here we re-evaluate China's carbon emissions using updated and harmonized energy consumption and clinker production data and two new and comprehensive sets of measured emission factors for Chinese coal. We find that total energy consumption in China was 10 per cent higher in 2000-2012 than the value reported by China's national statistics, that emission factors for Chinese coal are on average 40 per cent lower than the default values recommended by the Intergovernmental Panel on Climate Change, and that emissions from China's cement production are 45 per cent less than recent estimates. Altogether, our revised estimate of China's CO2 emissions from fossil fuel combustion and cement production is 2.49 gigatonnes of carbon (2 standard deviations = ±7.3 per cent) in 2013, which is 14 per cent lower than the emissions reported by other prominent inventories. Over the full period 2000 to 2013, our revised estimates are 2.9 gigatonnes of carbon less than previous estimates of China's cumulative carbon emissions. Our findings suggest that overestimation of China's emissions in 2000-2013 may be larger than China's estimated total forest sink in 1990-2007 (2.66 gigatonnes of carbon) or China's land carbon sink in 2000-2009 (2.6 gigatonnes of carbon).


Asunto(s)
Carbono/análisis , Materiales de Construcción/provisión & distribución , Combustibles Fósiles/estadística & datos numéricos , Dióxido de Carbono/análisis , Secuestro de Carbono , China , Cambio Climático , Carbón Mineral/estadística & datos numéricos , Árboles/metabolismo , Incertidumbre
2.
Surg Endosc ; 35(7): 3488-3491, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-32661710

RESUMEN

INTRODUCTION: Esophageal anastomotic stricture is a well-known complication after transhiatal esophagectomy (THE), but there is limited data regarding the initial management and subsequent outcomes after stricture dilation. There is concern that dilating to larger diameters upon the initial encounter, specifically with high-grade strictures, will lead to increased risk for complications. We therefore reviewed one surgeon's experience with esophageal dilations after THE and provided data and treatment recommendations based upon these findings. METHODS: A retrospective review of patients who underwent esophageal dilations ≥ 18 mm up to 20 mm after THE between 2006 and 2019 at our institution was performed. Patient demographics were n = 97, age = 70, 81 males. RESULTS: For all cases, the mean location, length, diameter of the stricture, and number of days from surgery and initial dilation were 20 cm, 1.9 cm, 6.7 mm, and 106 days, respectively. Most dilations (79%) occurred within 2 weeks to 3 months from surgery. 29.9% were dilated up to 18 mm, 10.3% were dilated up to 19 mm, and 59.8% were dilated up to 20 mm upon initial dilation. Even 1-mm-diameter lesions could be safely dilated upon 18-20 mm. In this study group there were no complications after endoscopic dilation that required hospitalization or further surgical or endoscopic interventions. CONCLUSION: These results suggest that early aggressive endoscopic management of esophageal anastomotic strictures after THE can be safely performed.


Asunto(s)
Neoplasias Esofágicas , Estenosis Esofágica , Anastomosis Quirúrgica/efectos adversos , Constricción Patológica , Dilatación , Neoplasias Esofágicas/cirugía , Estenosis Esofágica/etiología , Estenosis Esofágica/cirugía , Esofagectomía/efectos adversos , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
3.
Acta Neurochir (Wien) ; 163(11): 3161-3169, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33811521

RESUMEN

BACKGROUND: Currently, there are no guidelines for neurosurgeons treating patients with Cushing's disease (CD) when intraoperative adenoma identification is negative. Under these circumstances, a total hypophysectomy or hemi-hypophysectomy on the side indicated by inferior petrosal sinus sampling (IPSS) is the approach being used, although there is a subsequent risk of hypopituitarism. Data on whether one-third lateral pituitary gland resection results in cure of hypercortisolism and low rates of hypopituitarism remain inconclusive. METHODS: Retrospective single-center study of CD patients with failed intraoperative adenoma identification and subsequent resection of the lateral one-third of the pituitary gland as predicted by IPSS. We assessed (i) histopathological findings, (ii) early and long-term remission rates, and (iii) rates of additional pituitary hormone insufficiency. RESULTS: Ten women and three men met the inclusion criteria. At 3 months, remission was noted in six (46%) patients: three (23%) had histologically confirmed adenomas, two (15%) had ACTH hyperplasia, and one patient (8%) was positive for Crooke's hyaline degeneration. New pituitary hormone deficits were noted in two patients (15%). After a median (±SD) follow-up of 14±4 years, recurrence was noted in two (15%) patients. Long-term control of hypercortisolism was attained by 10 patients (77%), with additional therapies required in nine (69%) of them. CONCLUSIONS: In CD patients with failed intraoperative adenoma visualization, lateral one-third gland resection resulted in low morbidity and long-term remission in 31% of patients without the need for additional therapies. Bearing in mind the sample size of this audit, the indication for lateral one-third-gland resection has to be critically appraised and discussed with the patients before surgery.


Asunto(s)
Adenoma , Neoplasias Hipofisarias , Adenoma/cirugía , Hormona Adrenocorticotrópica , Femenino , Humanos , Masculino , Muestreo de Seno Petroso , Estudios Retrospectivos
4.
J Neuroradiol ; 48(1): 10-15, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31228539

RESUMEN

BACKGROUND: Asymmetric inferior petrosal sinuses (IPS) are not infrequently encountered during bilateral IPS sampling. There is little data on whether IPS symmetry influences success in predicting the adenoma side in patients with ACTH-dependent Cushing's syndrome (CS). OBJECTIVE: To assess the influence of IPS drainage patterns on detection of an adenoma in CS. METHODS: Retrospective single-center cohort analysis reviewing records of patients with CS and negative MRI findings who subsequently underwent BIPSS. RESULTS: BIPSS was performed in 38 patients with a mean age of 45±15 years. The overall technical success rate was 97% for bilateral cannulation. Asymmetric IPS were observed in 11 (39%) patients with Cushing's disease (CD). A side-to-side ACTH ratio was not significantly different between patients with symmetric outflow and those with asymmetric outflow at baseline (8.6±2.7 versus 16.4±6.0; P=0.45), but ratios were significantly different after ovine corticotropin-releasing hormone (oCRH) stimulation (6.0±2.5 versus 35.7±22.5; P=0.03). BIPSS correctly predicted the side of the adenoma in 25 (96%) patients with CD. Prediction was better when the venous outflow was symmetric (100%) rather than asymmetric (93%), although the difference was not significant (P=0.42). Remission from CS was achieved in 32 patients (87%), independent of the symmetry of IPS. CONCLUSIONS: Bearing in mind the sample size of this audit, asymmetric IPS at least do not seem to diminish the accuracy of diagnosis of ACTH-dependent CS, nor do they influence the clinical outcome.


Asunto(s)
Adenoma , Síndrome de Cushing , Neoplasias Hipofisarias , Adenoma/diagnóstico por imagen , Hormona Adrenocorticotrópica , Adulto , Animales , Hormona Liberadora de Corticotropina , Síndrome de Cushing/diagnóstico por imagen , Drenaje , Humanos , Persona de Mediana Edad , Muestreo de Seno Petroso , Estudios Retrospectivos , Ovinos
5.
J Craniofac Surg ; 28(7): e685-e687, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28885436

RESUMEN

Self-inflicted penetrating head injuries in patients with paranoid schizophrenia are an infrequent phenomenon. The authors report on a psychiatric patient who presented with epistaxis. Computed tomography showed a nail passing from the nasal cavity into the frontal lobe. Given the proximity to large intracranial vessels, a craniotomy was performed and the nail was retracted. The patient later reported having hammered the nail into the nasal cavity with the intention to "kill the voice in my head." Despite use of the latest imaging modalities, metal artifacts may have limited the assessment of vascular involvement. Surgical decision-making preventing secondary damage is crucial in them.


Asunto(s)
Cuerpos Extraños , Lóbulo Frontal/lesiones , Traumatismos Penetrantes de la Cabeza , Esquizofrenia Paranoide/complicaciones , Automutilación , Humanos , Masculino , Persona de Mediana Edad
6.
Amino Acids ; 48(8): 1913-27, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27129463

RESUMEN

Transplantation of neural progenitor cells (NPCs) is a promising experimental therapy for Huntington's disease (HD). The variables responsible for the success of this approach, including selection of the optimal developmental stage of the grafted cells, are however largely unknown. Supporting cellular energy metabolism by creatine (Cr) supplementation is a clinically translatable method for improving cell transplantation strategies. The present study aims at investigating differences between early (E14) and late (E18) developmental stages of rat striatal NPCs in vitro. NPCs were isolated from E14 and E18 embryos and cultured for 7 days with or without Cr [5 mM]. Chronic treatment significantly increased the percentage of GABA-immunoreactive neurons as compared to untreated controls, both in the E14 (170.4 ± 4.7 %) and the E18 groups (129.3 ± 9.3 %). This effect was greater in E14 cultures (p < 0.05). Similarly, short-term treatment for 24 h resulted in increased induction (p < 0.05) of the GABA-ergic phenotype in E14 (163.0 ± 10.4 %), compared to E18 cultures (133.3 ± 9.5 %). Total neuronal cell numbers and general viability were not affected by Cr (p > 0.05). Protective effects of Cr against a metabolic insult were equal in E14 and E18 NPCs (p > 0.05). Cr exposure promoted morphological differentiation of GABA-ergic neurons, including neurite length in both groups (p < 0.05), but the number of branching points was increased only in the E18 group (p < 0.05). Our results demonstrate that the role of Cr as a GABA-ergic differentiation factor depends on the developmental stage of striatal NPCs, while Cr-mediated neuroprotection is not significantly influenced. These findings have potential implications for optimizing future cell replacement strategies in HD.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Cuerpo Estriado/embriología , Creatina/farmacología , Embrión de Mamíferos/embriología , Neuronas GABAérgicas/metabolismo , Células-Madre Neurales/metabolismo , Animales , Cuerpo Estriado/citología , Embrión de Mamíferos/citología , Femenino , Neuronas GABAérgicas/citología , Células-Madre Neurales/citología , Ratas , Ratas Wistar
7.
Acta Neurochir (Wien) ; 158(9): 1711-20, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27416860

RESUMEN

BACKGROUND: Treatment of complex intracranial aneurysms requires strategic pre-interventional or preoperative planning. In addition to modern three-dimensional (3D) rotational angiography, computed tomography angiography (CTA) or magnetic resonance angiogram (MRA), a solid, tangible 3D model may improve anatomical comprehension and treatment planning. A 3D rapid prototyping (RP) technique based on multimodal imaging data was evaluated for use in planning of treatment for complex aneurysmal configurations. METHODS: Six patients with complex aneurysms were selected for 3D RP based on CTA and 3D rotational angiography data. Images were segmented using image-processing software to create virtual 3D models. Three-dimensional rapid prototyping techniques transformed the imaging data into physical 3D models, which were used and evaluated for interdisciplinary treatment planning. RESULTS: In all cases, the model provided a comprehensive 3D representation of relevant anatomical structures and improved understanding of related vessels. Based on the 3D model, primary bypass surgery with subsequent reconstruction of the aneurysm was then considered advantageous in all but one patient after simulation of multiple approaches. CONCLUSIONS: Preoperative prediction of intraoperative anatomy using the 3D model was considered helpful for treatment planning. The use of 3D rapid prototyping may enhance understanding of complex configurations in selected large or giant aneurysms, especially those pretreated with clips or coils.


Asunto(s)
Angiografía Cerebral/métodos , Embolización Terapéutica/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Aneurisma Intracraneal/cirugía , Modelación Específica para el Paciente , Adulto , Embolización Terapéutica/efectos adversos , Femenino , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Masculino , Persona de Mediana Edad
8.
W V Med J ; 112(4): 28-30, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27491099

RESUMEN

An appendiceal mucocele (AM) is an uncommon differential in the patient being evaluated for acute appendicitis. Although often asymptomatic, AMs can clinically mimic acute appendicitis, and preoperative distinction between these processes facilitates optimal management. We report the case of a 60-year-old male with an AM presenting with nausea and periumbilical pain radiating to the right lower quadrant. Literature relevant to the diagnosis and treatment of AMs is reviewed, with emphasis on diagnosis through radiographic imaging and surgical management. Abdominal CT scan or ultrasound are useful in identifying AMs preoperatively. A decision to perform a right hemicolectomy should be influenced by the criteria reported by Gonzalez-Moreno. The safety of the laparoscopic resection relative to an open appendectomy is debated.


Asunto(s)
Neoplasias del Apéndice/diagnóstico , Apendicitis/diagnóstico , Apéndice/diagnóstico por imagen , Cistoadenoma Mucinoso/diagnóstico , Mucocele/diagnóstico , Apendicectomía , Neoplasias del Apéndice/complicaciones , Neoplasias del Apéndice/cirugía , Apéndice/cirugía , Cistoadenoma Mucinoso/complicaciones , Cistoadenoma Mucinoso/cirugía , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana Edad , Mucocele/etiología , Mucocele/cirugía , Tomografía Computarizada por Rayos X
9.
Ergonomics ; 57(1): 66-73, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24354716

RESUMEN

Railroad workers often perform daily work activities on irregular surfaces, specifically on ballast rock. Previous research and injury epidemiology have suggested a relationship between working on irregular surfaces and postural instability. The purpose of this study was to examine the impact of walking on ballast for an extended duration on standing balance. A total of 16 healthy adult males walked on a 7.62 m × 4.57 m (25 ft × 15 ft) walking surface of no ballast (NB) or covered with ballast (B) of an average rock size of about 1 inch for 4 h. Balance was evaluated using dynamic posturography with the NeuroCom(®) Equitest System(™) prior to experiencing the NB or B surface and again every 30 min during the 4 h of ballast exposure. Dependent variables were the sway velocity and root-mean-square (RMS) sway components in the medial-lateral and anterior-posterior directions. Repeated measures ANOVA revealed statistically significant differences in RMS and sway velocity between ballast surface conditions and across exposure times. Overall, the ballast surface condition induced greater sway in all of the dynamic posturography conditions. Walking on irregular surfaces for extended durations has a deleterious effect on balance compared to walking on a surface without ballast. These findings of changes in balance during ballast exposure suggest that working on an irregular surface may impact postural control.


Asunto(s)
Equilibrio Postural/fisiología , Vías Férreas , Caminata/fisiología , Adolescente , Adulto , Análisis de Varianza , Fenómenos Biomecánicos , Marcha/fisiología , Humanos , Masculino , Salud Laboral , Propiedades de Superficie , Factores de Tiempo , Adulto Joven
10.
Am J Perinatol ; 30(3): 185-90, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22930157

RESUMEN

OBJECTIVE: To determine if tobacco use increases the incidence of preterm premature rupture of the membranes (pPROM) or alters perinatal outcomes after pPROM. STUDY DESIGN: This is a secondary analysis of the databases of three completed Eunice Kennedy Shriver National Institute of Child Health and Human Development-supported Maternal Fetal Medicine Units Network studies. Self-reported tobacco exposure data was obtained. Its relationship with the incidence of pPROM and associated neonatal outcome measures were assessed. RESULTS: There was no difference in the incidence of pPROM when comparing nonsmokers to those using tobacco. Although a trend was seen between the incidence of pPROM and the amount smoked, this did not reach statistical significance. Among the patients with pPROM, the use of tobacco was not associated with an increase in perinatal morbidity. CONCLUSION: Our data do not support a significant relationship between tobacco use and pPROM.


Asunto(s)
Rotura Prematura de Membranas Fetales/epidemiología , Fumar/epidemiología , Adolescente , Adulto , Factores de Edad , Femenino , Humanos , Incidencia , Modelos Logísticos , Análisis Multivariante , Embarazo , Nacimiento Prematuro/epidemiología , Infecciones del Sistema Genital/epidemiología , Estados Unidos/epidemiología , Vagina/microbiología , Adulto Joven
11.
Brain ; 134(Pt 6): 1777-89, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21616972

RESUMEN

Stem cell transplantation promises new hope for the treatment of stroke although significant questions remain about how the grafted cells elicit their effects. One hypothesis is that transplanted stem cells enhance endogenous repair mechanisms activated after cerebral ischaemia. Recognizing that bilateral reorganization of surviving circuits is associated with recovery after stroke, we investigated the ability of transplanted human neural progenitor cells to enhance this structural plasticity. Our results show the first evidence that human neural progenitor cell treatment can significantly increase dendritic plasticity in both the ipsi- and contralesional cortex and this coincides with stem cell-induced functional recovery. Moreover, stem cell-grafted rats demonstrated increased corticocortical, corticostriatal, corticothalamic and corticospinal axonal rewiring from the contralesional side; with the transcallosal and corticospinal axonal sprouting correlating with functional recovery. Furthermore, we demonstrate that axonal transport, which is critical for both proper axonal function and axonal sprouting, is inhibited by stroke and that this is rescued by the stem cell treatment, thus identifying another novel potential mechanism of action of transplanted cells. Finally, we established in vitro co-culture assays in which these stem cells mimicked the effects observed in vivo. Through immunodepletion studies, we identified vascular endothelial growth factor, thrombospondins 1 and 2, and slit as mediators partially responsible for stem cell-induced effects on dendritic sprouting, axonal plasticity and axonal transport in vitro. Thus, we postulate that human neural progenitor cells aid recovery after stroke through secretion of factors that enhance brain repair and plasticity.


Asunto(s)
Transporte Axonal/fisiología , Isquemia Encefálica/cirugía , Corteza Cerebral/citología , Células-Madre Neurales , Plasticidad Neuronal/fisiología , Análisis de Varianza , Animales , Biotina/análogos & derivados , Biotina/metabolismo , Infarto Encefálico/etiología , Infarto Encefálico/patología , Isquemia Encefálica/complicaciones , Supervivencia Celular , Células Cultivadas , Cuerpo Calloso/patología , Dendritas/fisiología , Dextranos/metabolismo , Modelos Animales de Enfermedad , Feto , Regulación de la Expresión Génica , Humanos , Masculino , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Células-Madre Neurales/citología , Células-Madre Neurales/fisiología , Células-Madre Neurales/trasplante , Desempeño Psicomotor/fisiología , ARN Mensajero/metabolismo , Ratas , Ratas Desnudas , Ratas Sprague-Dawley , Factores de Tiempo , Vibrisas/inervación
12.
Neuroradiology ; 54(5): 495-503, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21808987

RESUMEN

INTRODUCTION: Conventional MRI may still be an inaccurate method for the non-invasive detection of a microadenoma in adrenocorticotropin (ACTH)-dependent Cushing's syndrome (CS). Bilateral inferior petrosal sinus sampling (BIPSS) with ovine corticotropin-releasing hormone (oCRH) stimulation is an invasive, but accurate, intervention in the diagnostic armamentarium surrounding CS. Until now, there is a continuous controversial debate regarding lateralization data in detecting a microadenoma. Using BIPSS, we evaluated whether a highly selective placement of microcatheters without diversion of venous outflow might improve detection of pituitary microadenoma. METHODS: We performed BIPSS in 23 patients that met clinical and biochemical criteria of CS and with equivocal MRI findings. For BIPSS, the femoral veins were catheterized bilaterally with a 6-F catheter and the inferior petrosal sinus bilaterally with a 2.7-F microcatheter. A third catheter was placed in the right femoral vein. Blood samples were collected from each catheter to determine ACTH blood concentration before and after oCRH stimulation. RESULTS: In 21 patients, a central-to-peripheral ACTH gradient was found and the affected side determined. In 18 of 20 patients where transsphenoidal partial hypophysectomy was performed based on BIPSS findings, microadenoma was histologically confirmed. BIPSS had a sensitivity of 94% and a specificity of 67% after oCRH stimulation in detecting a microadenoma. Correct localization of the adenoma was achieved in all Cushing's disease patients. CONCLUSION: BIPSS remains the gold standard in the detection of a microadenoma in CS. Our findings show that the selective placement of microcatheters without venous outflow diversion might further enhance better recognition to localize the pituitary tumor.


Asunto(s)
Adenoma/sangre , Síndrome de Cushing/sangre , Muestreo de Seno Petroso/métodos , Neoplasias Hipofisarias/sangre , Adenoma/diagnóstico , Hormona Adrenocorticotrópica/sangre , Adulto , Anciano , Angiografía , Cateterismo , Niño , Femenino , Vena Femoral , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neoplasias Hipofisarias/diagnóstico , Estudios Retrospectivos , Sensibilidad y Especificidad
13.
Acta Neurochir (Wien) ; 154(3): 423-31; discussion 431, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22113556

RESUMEN

BACKGROUND: Carotid endarterectomy (CEA) reduces the risk of stroke in patients with symptomatic (>50%) and asymptomatic (>60%) carotid artery stenosis. Here we report the midterm results of a microsurgical non-patch technique and compare these findings to those in the literature. METHODS: From 1998 to 2009 we treated 586 consecutive patients with CEA. CEA was performed, under general anesthesia, with a surgical microscope using a non-patch technique. Somatosensory evoked potential and transcranial Doppler were continuously monitored. Cross-clamping was performed under EEG burst suppression and adaptive blood pressure increase. Follow-up was performed by an independent neurologist. Mortality at 30 days and morbidity such as major and minor stroke, peripheral nerve palsy, hematoma and cardiac complications were recorded. The restenosis rate was assessed using duplex sonography 1 year after surgery. RESULTS: A total of 439 (75%) patients had symptomatic and 147 (25%) asymptomatic stenosis; 49.7% of the stenoses were on the right-side. Major perioperative strokes occurred in five (0.9%) patients [n = 4 (0.9%) symptomatic; n = 1 (0.7%) asymptomatic patients]. Minor stroke was recorded in six (1%) patients [n = 4 (0.9%) symptomatic; n = 2 (1.3%) asymptomatic patients]. Two patients with symptomatic stenoses died within 1 month after surgery. Nine patients (1.5%) had reversible peripheral nerve palsies, and nine patients (1.5%) suffered a perioperative myocardial infarction. High-grade (>70%) restenosis at 1 year was observed in 19 (3.2%) patients [n = 12 (2.7%) symptomatic; n = 7 (4.7%) asymptomatic patients]. CONCLUSIONS: The midterm rate of restenosis was low when using a microscope-assisted non-patch endarterectomy technique. The 30-day morbidity and mortality rate was comparable or lower than those in recently published surgical series.


Asunto(s)
Arteria Carótida Interna/cirugía , Estenosis Carotídea/mortalidad , Estenosis Carotídea/cirugía , Endarterectomía Carotidea/mortalidad , Microcirugia/mortalidad , Complicaciones Posoperatorias/mortalidad , Anciano , Arteria Carótida Interna/diagnóstico por imagen , Arteria Carótida Interna/patología , Estenosis Carotídea/fisiopatología , Estudios de Cohortes , Endarterectomía Carotidea/métodos , Endarterectomía Carotidea/estadística & datos numéricos , Femenino , Humanos , Masculino , Microcirugia/métodos , Microcirugia/estadística & datos numéricos , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/fisiopatología , Estudios Prospectivos , Prevención Secundaria , Ultrasonografía
14.
Front Neurol ; 13: 862809, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35847222

RESUMEN

Background: To detect restenosis after carotid endarterectomy (CEA), long-term monitoring is required. However, non-selective follow-up is controversial and can be limited by costs and logistical considerations. Objective: To examine the value of immediate perioperative vessel flow measurements after CEA using quantitative magnetic resonance angiography (QMRA) to detect patients at risk of long-term restenosis. Methods: A prospective cohort study with long-term sonographic follow-up after CEA for symptomatic internal carotid artery stenosis (ICAs) > 50%. In all patients, vessel flow has been assessed both pre- and postoperatively using QMRA within ±3 days of surgery. Data on QMRA assessment were analyzed to identify patients at risk of restenosis for up to 10 years. Results: Restenosis was recorded in 4 of 24 patients (17%) at a median follow-up of 6.8 ± 2.6 years. None of them experienced an ischemic event. Perioperative flow differences were significantly greater in patients without long-term restenosis, both for the ipsilateral ICA (p < 0.001) and MCA (p = 0.03), compared to those with restenosis (p = 0.22 and p = 0.3, respectively). The ICA mean flow ratio (p = 0.05) tended to be more effective than the MCA ratio in predicting restenosis over the long term (p = 0.35). Conclusion: Our preliminary findings suggest that QMRA-based mean flow increases after CEA may be predictive of restenosis over the long term. Perioperative QMRA assessment could become an operator-independent screening tool to identify a subgroup of patients at risk for restenosis, in whom long-term monitoring is advised.

15.
Stroke ; 42(10): 2923-31, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21836091

RESUMEN

BACKGROUND AND PURPOSE: The inflammatory response is a critical component of ischemic stroke. In addition to its physiological role, the mechanisms behind transendothelial recruitment of immune cells also offer a unique therapeutic opportunity for translational stem cell therapies. Recent reports have demonstrated homing of neural stem cells (NSC) into the injured brain areas after intravascular delivery. However, the mechanisms underlying the process of transendothelial recruitment remain largely unknown. Here we describe the critical role of the chemokine CCL2 and its receptor CCR2 in targeted homing of NSC after ischemia. METHODS: Twenty-four hours after induction of stroke using the hypoxia-ischemia model in mice CCR2+/+ and CCR2-/- reporter NSC were intra-arterially delivered. Histology and bioluminescence imaging were used to investigate NSC homing to the ischemic brain. Functional outcome was assessed with the horizontal ladder test. RESULTS: Using NSC isolated from CCR2+/+ and CCR2-/- mice, we show that receptor deficiency significantly impaired transendothelial diapedesis specifically in response to CCL2. Accordingly, wild-type NSC injected into CCL2-/- mice exhibited significantly decreased homing. Bioluminescence imaging showed robust recruitment of CCR2+/+ cells within 6 hours after transplantation in contrast to CCR2-/- cells. Mice receiving CCR2+/+ grafts after ischemic injury showed a significantly improved recovery of neurological deficits as compared to animals with transplantation of CCR2-/- NSC. CONCLUSIONS: The CCL2/CCR2 interaction is critical for transendothelial recruitment of intravascularly delivered NSC in response to ischemic injury. This finding could have significant implications in advancing minimally invasive intravascular therapeutics for regenerative medicine or cell-based drug delivery systems for central nervous system diseases.


Asunto(s)
Isquemia Encefálica/terapia , Quimiocina CCL2/metabolismo , Células-Madre Neurales/trasplante , Receptores CCR2/metabolismo , Animales , Encéfalo/metabolismo , Isquemia Encefálica/metabolismo , Diferenciación Celular , Proliferación Celular , Quimiocina CCL2/genética , Masculino , Ratones , Ratones Noqueados , Células-Madre Neurales/metabolismo , Receptores CCR2/genética , Recuperación de la Función , Medicina Regenerativa
16.
Pituitary ; 14(3): 222-30, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21170594

RESUMEN

Despite the fact that consensus guidelines recommend long-term dopamine agonist (DA) therapy as a first-line approach to the treatment of small prolactinoma, some patients continue to prefer a primary surgical approach. Concerns over potential adverse effects of long-term medical therapy and/or the desire to become pregnant and avoid long-term medication are often mentioned as reasons to pursue surgical removal. In this retrospective study, 34 consecutive patients (30 female, 4 male) preferably underwent primary pituitary surgery without prior DA treatment for small prolactinomas (microprolactinoma 1-10 mm, macroprolactinoma 11-20 mm) at the Department of Neurosurgery, University of Bern, Switzerland. At the time of diagnosis, 31 of 34 patients (91%) presented with symptoms. Patients with microprolactinomas had significantly lower preoperative prolactin (PRL) levels compared to patients with macroprolactinomas (median 143 µg/l vs. 340 µg/l). Ninety percent of symptomatic patients experienced significant improvement of their signs and symptoms upon surgery. The postoperative PRL levels (median 3.45 µg/l) returned to normal in 94% of patients with small prolactinomas. There was no mortality and no major morbidities. One patient suffered from hypogonadotropic hypogonadism after surgery despite postoperative normal PRL levels. Long-term remission was achieved in 22 of 24 patients (91%) with microprolactinomas, and in 8 of 10 patients (80%) with macroprolactinomas after a median follow-up period of 33.5 months. Patients with small prolactinomas can safely consider pituitary surgery in a specialized centre with good chance of long-term remission as an alternative to long-term DA therapy.


Asunto(s)
Agonistas de Dopamina/uso terapéutico , Prolactinoma/tratamiento farmacológico , Prolactinoma/cirugía , Adolescente , Adulto , Femenino , Humanos , Hiperprolactinemia/sangre , Hiperprolactinemia/tratamiento farmacológico , Hiperprolactinemia/cirugía , Masculino , Persona de Mediana Edad , Prolactina/sangre , Prolactinoma/sangre , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
17.
J Clin Transl Endocrinol ; 24: 100258, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34195008

RESUMEN

OBJECTIVES: High prolactin levels have been associated with weight gain and impaired metabolic profiles. While treatment with dopamine agonists (DAs) has been shown to improve these parameters, there is a lack of surgical series on its comparative effect in prolactinoma patients. METHODS: In this retrospective, comparative study, consecutive patients with a prolactinoma were enrolled if treated with first-line transsphenoidal surgery (TSS) or with DAs. Patients with prolactinomas of Knosp grade >2 and those with a follow-up <24 months were excluded, as were patients with missing laboratory metabolic parameters at baseline and over the long-term. Effects of either treatment on BMI and the metabolic profile were analyzed, and independent risk factors for long-term obesity were calculated. RESULTS: Primary treatment was TSS for 12 patients (40%) and DAs for 18 patients (60%). At diagnosis, no significant differences between the two cohorts were observed with regard to adenoma size, Knosp grading, baseline prolactin (PRL) levels, prevalence of hypogonadism, or laboratory metabolic parameters. Mean follow-up was 51.9 months (range, 24-158). Over the long-term, both TSS and DAs led to the control of hyperprolactinemia (92% vs. 72%) and hypogonadism (78% vs. 83%) in the majority of patients. While a significant decrease in patients' BMI and fasting glucose were observed, changes in the lipid profile were marginal and independent of the treatment modality. At baseline, increased BMI-but not the primary treatment strategy-was an independent predictor of long-term obesity. CONCLUSIONS: Over the long-term, patients' BMI and FG improve, but changes in the metabolic profile are marginal and independent of the primary treatment. It is presumable that not DAs per se, but rather the control of hyperprolactinemia plays a role in patients' metabolic profile alterations.

18.
Sci Rep ; 11(1): 5122, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33664388

RESUMEN

While prolactinoma patients have high bone turnover, current data are inconclusive when it comes to determining whether correction of hyperprolactinemia and associated hypogandism improves osteodensitometric data in men and women over the long term. In a large cohort of including 40 men and 60 women, we studied the long-term impact of prolactinoma treatment on bone mineral density (BMD) in men versus women, assessed adverse effects of a primary surgical or medical approach, and evaluated data for risk factors for impaired BMD at last follow-up using multivariate regression analyses. Median duration of follow-up was 79 months (range 13-408 months). Our data indicate that the prevalence of impaired BMD remained significantly higher in men (37%) than in women (7%, p < 0.001), despite the fact that hyperprolactinemia and hypogonadism are under control in the majority of men. We found that persistent hyperprolactinemia and male sex were independent risk factors for long-term bone impairment. Currently, osteoporosis prevention and treatment focus primarily on women, yet special attention to bone loss in men with prolactinomas is advised. Bone impairment as "end organ" reflects the full range of the disease and could become a surrogate marker for the severity of long-lasting hyperprolactinemia and associated hypogonadism.


Asunto(s)
Hiperprolactinemia/tratamiento farmacológico , Hipogonadismo/tratamiento farmacológico , Osteoporosis/diagnóstico por imagen , Prolactinoma/tratamiento farmacológico , Adulto , Densidad Ósea/efectos de los fármacos , Femenino , Humanos , Hiperprolactinemia/complicaciones , Hiperprolactinemia/metabolismo , Hiperprolactinemia/patología , Hipogonadismo/complicaciones , Hipogonadismo/metabolismo , Hipogonadismo/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteoporosis/etiología , Osteoporosis/metabolismo , Osteoporosis/patología , Prolactinoma/complicaciones , Prolactinoma/metabolismo , Prolactinoma/patología , Factores de Riesgo
19.
Stroke ; 41(9): 2064-70, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20616329

RESUMEN

BACKGROUND AND PURPOSE: Intravascular transplantation of neural stem cells represents a minimally invasive therapeutic approach for the treatment of central nervous system diseases. The cellular biodistribution after intravascular injection needs to be analyzed to determine the ideal delivery modality. We studied the biodistribution and efficiency of targeted central nervous system delivery comparing intravenous and intra-arterial (IA) administration of neural stem cells after brain ischemia. METHODS: Mouse neural stem cells were transduced with a firefly luciferase reporter gene for bioluminescence imaging (BLI). Hypoxic-ischemia was induced in adult mice and reporter neural stem cells were transplanted IA or intravenous at 24 hours after brain ischemia. In vivo BLI was used to track transplanted cells up to 2 weeks after transplantation and ex vivo BLI was used to determine single organ biodistribution. RESULTS: Immediately after transplantation, BLI signal from the brain was 12 times higher in IA versus intravenous injected animals (P<0.0001). After IA injection, 69% of the total luciferase activity arose from the brain early after transplantation and 93% at 1 week. After intravenous injection, 94% of the BLI signal was detected in the lungs (P=0.004) followed by an overall 94% signal loss at 1 week, indicating lack of cell survival outside the brain. Ex vivo single organ analysis showed a significantly higher BLI signal in the brain than in the lungs, liver, and kidneys at 1 week (P<0.0001) and 2 weeks in IA (P=0.007). CONCLUSIONS: IA transplantation results in superior delivery and sustained presence of neural stem cells in the ischemic brain in comparison to intravenous infusion.


Asunto(s)
Hipoxia-Isquemia Encefálica/terapia , Neuronas/trasplante , Células Madre/metabolismo , Análisis de Varianza , Animales , Recuento de Células , Células Cultivadas , Citometría de Flujo , Inmunohistoquímica , Imagen por Resonancia Magnética , Ratones , Trasplante de Células Madre , Distribución Tisular , Transducción Genética
20.
Neurobiol Dis ; 37(2): 275-83, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19822211

RESUMEN

Stem cell transplantation has evolved as a promising experimental treatment approach for stroke. In this review, we address the major hurdles for successful translation from basic research into clinical applications and discuss possible strategies to overcome these issues. We summarize the results from present pre-clinical and clinical studies and focus on specific areas of current controversy and research: (i) the therapeutic time window for cell transplantation; (ii) the selection of patients likely to benefit from such a therapy; (iii) the optimal route of cell delivery to the ischemic brain; (iv) the most suitable cell types and sources; (v) the potential mechanisms of functional recovery after cell transplantation; and (vi) the development of imaging techniques to monitor cell therapy.


Asunto(s)
Encéfalo/cirugía , Trasplante de Células Madre/métodos , Accidente Cerebrovascular/cirugía , Animales , Encéfalo/patología , Encéfalo/fisiopatología , Proliferación Celular , Supervivencia de Injerto/fisiología , Humanos , Microinyecciones/métodos , Microinyecciones/tendencias , Selección de Paciente , Recuperación de la Función/fisiología , Células Madre/citología , Células Madre/fisiología , Accidente Cerebrovascular/fisiopatología , Factores de Tiempo
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