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1.
AJNR Am J Neuroradiol ; 44(4): 447-452, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36958801

RESUMEN

BACKGROUND AND PURPOSE: Randomized trials in the late window have demonstrated the efficacy and safety of endovascular thrombectomy in large-vessel occlusions. Patients with M2-segment MCA occlusions were excluded from these trials. We compared outcomes with endovascular thrombectomy in patients with M2-versus-M1 occlusions presenting 6-24 hours after symptom onset. MATERIALS AND METHODS: Analyses were on pooled data from studies enrolling patients with stroke treated with endovascular thrombectomy 6-24 hours after symptom onset. We compared 90-day functional independence (mRS ≤ 2), mortality, symptomatic intracranial hemorrhage, and successful reperfusion (expanded TICI = 2b-3) between patients with M2 and M1 occlusions. The benefit of successful reperfusion was then assessed among patients with M2 occlusion. RESULTS: Of 461 patients, 367 (79.6%) had M1 occlusions and 94 (20.4%) had M2 occlusions. Patients with M2 occlusions were older and had lower median baseline NIHSS scores. Patients with M2 occlusion were more likely to achieve 90-day functional independence than those with M1 occlusion (adjusted OR = 2.13; 95% CI, 1.25-3.65). There were no significant differences in the proportion of successful reperfusion (82.9% versus 81.1%) or mortality (11.2% versus 17.2%). Symptomatic intracranial hemorrhage risk was lower in patients with M2-versus-M1 occlusions (4.3% versus 12.2%, P = .03). Successful reperfusion was independently associated with functional independence among patients with M2 occlusions (adjusted OR = 2.84; 95% CI, 1.11-7.29). CONCLUSIONS: In the late time window, patients with M2 occlusions treated with endovascular thrombectomy achieved better clinical outcomes, similar reperfusion, and lower symptomatic intracranial hemorrhage rates compared with patients with M1 occlusion. These results support the safety and benefit of endovascular thrombectomy in patients with M2 occlusions in the late window.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular , Humanos , Resultado del Tratamiento , Accidente Cerebrovascular/etiología , Trombectomía/métodos , Hemorragias Intracraneales/cirugía , Hemorragias Intracraneales/etiología , Procedimientos Endovasculares/métodos , Isquemia Encefálica/etiología , Estudios Retrospectivos
2.
Ann R Coll Surg Engl ; 105(2): 126-131, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35175862

RESUMEN

INTRODUCTION: Precise geographical localisation of colonic neoplasia is a prerequisite for proper laparoscopic oncological resection. Preoperative endoscopic peri-tumoural tattoo practice is routinely recommended but seldom scrutinised. METHODS: A retrospective review of recent consecutive patients with preoperative endoscopic lesional tattoo who underwent laparoscopic colonic resection as identified from our prospectively maintained cancer database with supplementary clinical chart and radiological, histological, endoscopic and theatre database/logbook interrogation. RESULTS: Some 210 patients with 'tattooed' colonic neoplasia were identified, of whom 169 underwent laparoscopic surgery (mean age 68 years, median BMI 27.8kg/m2, male-to-female ratio 95:74). The majority of tumours were malignant (149; 88%), symptomatic (133; 79%) and proximal to the splenic flexure (92; 54%). Inaccurate colonoscopist localisation judgement occurred in 12% of cases, 60% of which were corrected by preoperative staging computed tomography scan. A useful lesional tattoo was absent in 11/169 cases (6.5%) being specifically stated as present in 104 operation notes (61%) and absent in 10 (5.9%). Tumours missing overt peritumoral tattoos intraoperatively were more likely to be smaller, earlier stage and injected longer preoperatively (p=0.006), although half had histological ink staining. Eight lesions missing tattoos were radiologically occult. Four (44%) of these patients had on-table colonoscopy, and five (55%) needed laparotomy (conversion rate 55% vs 23% overall, p<0.005) with one needing a second operation to resect the initially missed target lesion. Mean (range) operative duration and postoperative length of stay of those missing tattoos compared with those with tattoos was 200 (78-300) versus 188 (50-597) min and 15.5 (4-22) versus 12(4-70) days (p>0.05). CONCLUSIONS: Tattoo in advance of attempting laparoscopic resection is vital for precision cancer surgery especially for radiologically unseen tumours to avoid adverse clinical consequence.


Asunto(s)
Neoplasias del Colon , Laparoscopía , Tatuaje , Humanos , Masculino , Femenino , Anciano , Tatuaje/métodos , Estudios Retrospectivos , Cuidados Preoperatorios/métodos , Neoplasias del Colon/cirugía , Neoplasias del Colon/patología , Laparoscopía/efectos adversos , Laparoscopía/métodos , Colonoscopía/métodos
3.
Interv Neuroradiol ; 28(2): 213-218, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34121488

RESUMEN

BACKGROUND AND PURPOSE: Aspiration is a successful technique used in thrombectomy for acute stroke. It is contingent upon the appropriate position of the aspiration catheter, so that it is in contact with the thrombus. However, navigating the craniocervical vasculature is challenging is some patients. The wedge microcatheter (MicroVention®) is designed to reduce the gap between the microcatheter and the SofiaPlus 6F catheter for ease of advancement. The purpose of this study is to describe our initial experience with the wedge microcatheter. MATERIALS AND METHODS: A retrospective review of 38 consecutive patients in whom the wedge microcatheter was used during thrombectomy was performed to determine whether the wedge microcatheter was successful in delivering the Sofia catheter to the desired location. RESULTS: We have found this device to be successful in delivering the aspiration catheter to the correct position in 97% (N = 37) of cases. It was used predominantly to pass the origin of branching vessels and also to navigate the tortuous cavernous and petrous segments of the ICA. CONCLUSION: The wedge microcatheter is a successful tool in delivering the aspiration catheter to the desired vessel for revascularisation.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular , Trombosis , Isquemia Encefálica/cirugía , Catéteres , Procedimientos Endovasculares/métodos , Humanos , Estudios Retrospectivos , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Resultado del Tratamiento
5.
BJOG ; 128(4): 676-684, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32935467

RESUMEN

OBJECTIVE: To explore fetal medicine specialists' experiences of caring for parents following a diagnosis of fatal fetal anomaly (FFA) during the implementation of termination of pregnancy (TOP) for FFA for the first time. DESIGN: Qualitative study. SETTING: Fetal medicine units in the Republic of Ireland. POPULATION: Ten fetal medicine specialists from five of the six fetal medicine units. METHODS: nvivo 12 assisted in the thematic analysis of semi-structured in-depth face-to-face interviews. MAIN OUTCOME MEASURES: Fetal medicine specialists' experiences of prenatal diagnosis and holistic management of pregnancies complicated by FFA. RESULTS: Four themes were identified: 'not fatal enough', 'interactions with colleagues', 'supporting pregnant women' and 'internal conflict and emotional challenges'. Fetal medicine specialists feared getting an FFA diagnosis incorrect because of media scrutiny and criminal liability associated with the TOP for FFA legislation. Challenges with the ambiguous and 'restrictive' legislation were identified that 'ostracised' severe anomalies. Teamwork was essential to facilitate opportunities for learning and peer support; however, conflict with colleagues was experienced regarding the diagnosis of FFA, the provision of feticide and palliative care to infants born alive following TOP for FFA. Participants reported challenges implementing TOP for FFA, including the absence of institutional support and 'stretched' resources. Fetal medicine specialists experienced internal conflict and a psychological burden providing TOP for FFA, but did so to 'provide full care for women'. CONCLUSIONS: Our study identified challenges regarding the suitability of the Irish legislation for TOP for FFA and its rapid introduction into clinical practice. It illustrates the importance of institutional and peer support, as well as the need for supportive management, in the provision of a new service. TWEETABLE ABSTRACT: The implementation of termination services for fatal fetal anomaly is complex and requires institutional support.


Asunto(s)
Aborto Eugénico , Actitud del Personal de Salud , Anomalías Congénitas , Perinatología , Atención Prenatal , Relaciones Profesional-Paciente , Aborto Eugénico/ética , Aborto Eugénico/psicología , Femenino , Humanos , Relaciones Interprofesionales , Entrevistas como Asunto , Irlanda , Perinatología/ética , Embarazo , Atención Prenatal/ética , Atención Prenatal/organización & administración , Atención Prenatal/psicología , Relaciones Profesional-Paciente/ética , Investigación Cualitativa
6.
Nat Commun ; 11(1): 6036, 2020 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-33247130

RESUMEN

Human activities are transforming grassland biomass via changing climate, elemental nutrients, and herbivory. Theory predicts that food-limited herbivores will consume any additional biomass stimulated by nutrient inputs ('consumer-controlled'). Alternatively, nutrient supply is predicted to increase biomass where herbivores alter community composition or are limited by factors other than food ('resource-controlled'). Using an experiment replicated in 58 grasslands spanning six continents, we show that nutrient addition and vertebrate herbivore exclusion each caused sustained increases in aboveground live biomass over a decade, but consumer control was weak. However, at sites with high vertebrate grazing intensity or domestic livestock, herbivores consumed the additional fertilization-induced biomass, supporting the consumer-controlled prediction. Herbivores most effectively reduced the additional live biomass at sites with low precipitation or high ambient soil nitrogen. Overall, these experimental results suggest that grassland biomass will outstrip wild herbivore control as human activities increase elemental nutrient supply, with widespread consequences for grazing and fire risk.


Asunto(s)
Biomasa , Pradera , Herbivoria/fisiología , Nitrógeno/análisis , Fósforo/análisis , Intervalos de Confianza , Fertilizantes , Factores de Tiempo
7.
Ann R Coll Surg Engl ; 102(6): 422-428, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32326723

RESUMEN

INTRODUCTION: Endoscopic vein harvest is the technique of choice in North America, where it constitutes 80% of conduit harvest for coronary artery bypass grafting. The UK has much lower rates, despite demonstrable perioperative benefits. Concerns about patency and long-term survival are often cited as reasons for poor uptake and evidence in the literature thus far has only addressed mid-term outcomes. We sought to identify the long-term survival of patients undergoing endoscopic vein harvest compared with a contemporaneous cohort of open vein harvest. MATERIALS AND METHODS: This was a retrospective cohort study of all consecutive patients undergoing isolated coronary artery bypass grafting at a single institution between 2007 and 2017. All-cause long-term mortality was compared using Kaplan-Meier curves and log-rank analysis. RESULTS: A total of 7,527 patients undergoing coronary artery bypass grafting (1,029 receiving endoscopic vein harvest) were studied. The groups were well matched for preoperative characteristics, except that there were more patients with triple-vessel disease and good left-ventricular function in the endoscopic vein harvest group. There was no statistically significant difference in the long-term survival (p = 0.23). At five years (median follow-up), survival was 86.1% (95% confidence interval 85.3-87.0) in the open vein harvest group compared with 85.5% (95% confidence interval 82.8-88.2) in the endoscopic vein harvest group. DISCUSSION AND CONCLUSION: Endoscopic vein harvest does not affect long-term survival in an unselected population. The contraindications for minimally invasive vein harvest in coronary artery bypass grafting are increasingly diminishing.


Asunto(s)
Puente de Arteria Coronaria/métodos , Enfermedad de la Arteria Coronaria/mortalidad , Endoscopía/métodos , Vena Safena/trasplante , Infección de la Herida Quirúrgica/epidemiología , Recolección de Tejidos y Órganos/métodos , Anciano , Puente de Arteria Coronaria/efectos adversos , Enfermedad de la Arteria Coronaria/cirugía , Endoscopía/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Infección de la Herida Quirúrgica/etiología , Recolección de Tejidos y Órganos/efectos adversos , Resultado del Tratamiento , Grado de Desobstrucción Vascular
8.
Cereb Cortex ; 30(2): 563-574, 2020 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-31188425

RESUMEN

Disruption of attention is an early and disabling symptom of Alzheimer's disease (AD). The underlying cellular mechanisms are poorly understood and treatment options for patients are limited. These early attention deficits are evident in the TgCRND8 mouse, a well-established murine model of AD that recapitulates several features of the disease. Here, we report severe impairment of the nicotinic receptor-mediated excitation of prefrontal attentional circuitry in TgCRND8 mice relative to wild-type littermate controls. We demonstrate that this impairment can be remedied by apamin, a bee venom neurotoxin peptide that acts as a selective antagonist to the SK family of calcium-sensitive potassium channels. We probe this seeming upregulation of calcium-sensitive inhibition and find that the attenuated nicotinic firing rates in TgCRND8 attention circuits are mediated neither by greater cellular calcium signals nor by elevated SK channel expression. Instead, we find that TgCRND8 mice show enhanced functional coupling of nicotinic calcium signals to inhibition. This SK-mediated inhibition exerts a powerful negative feedback on nicotinic excitation, dampening attention-relevant signaling in the TgCRND8 brain. These mechanistic findings identify a new cellular target involved in the modulation of attention and a novel therapeutic target for early attention deficits in AD.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Apamina/administración & dosificación , Corteza Prefrontal/fisiología , Células Piramidales/fisiología , Receptores Nicotínicos/fisiología , Animales , Modelos Animales de Enfermedad , Femenino , Masculino , Potenciales de la Membrana , Ratones Endogámicos C57BL , Ratones Transgénicos , Canales de Potasio de Pequeña Conductancia Activados por el Calcio/antagonistas & inhibidores
9.
Nat Commun ; 10(1): 4981, 2019 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-31672992

RESUMEN

Soil nitrogen mineralisation (Nmin), the conversion of organic into inorganic N, is important for productivity and nutrient cycling. The balance between mineralisation and immobilisation (net Nmin) varies with soil properties and climate. However, because most global-scale assessments of net Nmin are laboratory-based, its regulation under field-conditions and implications for real-world soil functioning remain uncertain. Here, we explore the drivers of realised (field) and potential (laboratory) soil net Nmin across 30 grasslands worldwide. We find that realised Nmin is largely explained by temperature of the wettest quarter, microbial biomass, clay content and bulk density. Potential Nmin only weakly correlates with realised Nmin, but contributes to explain realised net Nmin when combined with soil and climatic variables. We provide novel insights of global realised soil net Nmin and show that potential soil net Nmin data available in the literature could be parameterised with soil and climate data to better predict realised Nmin.

10.
Clin Radiol ; 74(12): 950-955, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31521325

RESUMEN

AIMS: To determine the experience of a regional stroke referral centre of external referrals for endovascular thrombectomy (EVT) in patients with symptoms of acute ischaemic stroke (AIS) and large vessel occlusion (LVO). MATERIALS AND METHODS: Data were collected prospectively over two 4-month periods (2017-2018) on consecutive external referrals for EVT. Baseline demographics, imaging findings, and key time parameters were recorded. Reasons for not transferring patients and for not performing EVT were recorded. Key time intervals were calculated and compared between the transferred and non-transferred group with and without intracranial occlusion and between the transferred patients who underwent thrombectomy and those who did not. RESULTS: Two hundred and sixty-two patients were referred. Sixty-one percent (n=159) were accepted and transferred for treatment. Of those transferred, 86% (n=136) had EVT. Fourteen percent (n=23) were unsuitable for EVT on arrival due to no vessel occlusion (48% n=11), poor Alberta Stroke Program Early CT Score (ASPECTS)/established infarct (30%, n=7) haemorrhage (9%, n=2), and clinical recovery (13% n=3). One hundred and three patients (39%) were ineligible for EVT following phone discussion due to absence of intracranial occlusion (59%, n=61), low ASPECTS (22%, n=23), distal occlusion (4%, n=4), low/improving National Institutes of Health Stroke Scale (NIHSS; 10.7%, n=11), and poor modified Rankin Scale (mRS) at baseline (3%, n=3). Patients with LVO but not transferred had longer onset to hospital arrival time compared with those transferred 151.5 versus 91 minutes (p<0.005), with a trend also toward a longer door to CT/CTA 40 minutes versus 30 minutes (p=0.142). CONCLUSION: These data provide valuable insights into the service provision of a comprehensive stroke network. The present rates of EVT and futile transfers are modest compared to published data. Access to neuroradiology and specialised stroke assessment is crucial to optimise time to treatment.


Asunto(s)
Derivación y Consulta/estadística & datos numéricos , Accidente Cerebrovascular/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Transferencia de Pacientes/estadística & datos numéricos , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/diagnóstico por imagen , Trombectomía/estadística & datos numéricos , Factores de Tiempo
11.
AJNR Am J Neuroradiol ; 40(8): 1335-1341, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31320463

RESUMEN

BACKGROUND AND PURPOSE: Direct aspiration is a recognized technique for revascularization in large-vessel ischemic strokes. There is ongoing debate regarding its efficacy compared with stent retrievers. Every delay in achieving revascularization and a decrease in reperfusion rates reduces the likelihood of patients achieving functional independence. We propose a standardized setup technique for aspiration-first for all anterior circulation thrombectomy procedures for increasing speed and recanalization rates. MATERIALS AND METHODS: We analyzed 127 consecutive patients treated by a standardized approach to thrombectomy with an intention to perform aspiration-first compared with 127 consecutive patients treated with a stent retriever-first approach. Key time metrics evaluated included groin to first angiogram, first angiogram to reperfusion, groin to first reperfusion, and length of the procedure. The degree of successful recanalization (TICI 2b-3) and the number of passes were compared between the 2 groups. RESULTS: In 127 patients who underwent the standardized technique, the median time from groin puncture to first reperfusion was 18 minutes compared with 26 minutes (P < .001). The duration of the procedure was shorter compared with the stent retriever group (26 minutes in the aspiration first group versus 47 minutes, P < .001) and required fewer passes (mean, 2.4 versus 3.1; P < .05). A higher proportion of patients had a TICI score of 2b-3 in the aspiration-first group compared with stent retriever group (96.1% versus 85.8%, P < .005). CONCLUSIONS: Our study highlights the increasing speed and recanalization rates achieved with fewer passes in a standardized approach to thrombectomy with an intention to attempt aspiration-first. Any attempt to reduce revascularization time and increase successful recanalization should be used.


Asunto(s)
Reperfusión/métodos , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Trombectomía/normas , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reperfusión/instrumentación , Reperfusión/normas , Trombectomía/instrumentación , Resultado del Tratamiento
12.
Clin Radiol ; 74(9): 731.e21-731.e25, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31122715

RESUMEN

AIMS: To determine the workload of acute computed tomography angiography (CTA) in patients presenting with suspected acute ischaemic stroke (AIS) and rate of large vessel occlusion (LVO) and thrombectomy relative to suspected and confirmed stroke diagnoses across three stroke centres within the Republic of Ireland. MATERIALS AND METHODS: A retrospective review of data from three stroke centres, one of which provides a 24-hour thrombectomy service was undertaken. The number of CTA studies performed from January 2015 to December 2017 for suspected AIS was quantified using the national PACS in addition to occlusion location, collateral status, and rates of LVO and thrombectomy. The hospital inpatient enquiry (HIPE) system was searched for all patients with a primary discharge diagnosis of stroke and then correlated with patients who underwent CTA on admission. RESULTS: A total of 2,358 CTA studies were performed for suspected AIS during the study period across three stroke centres. LVO was demonstrated in 18.4% of suspected AIS, 18.4% of primary discharge stroke diagnoses, and 40.2% of confirmed AIS who underwent CTA. A total of 283 thrombectomies were performed of which 64.6% were LVO. Thrombectomy was performed in 12% of suspected AIS, 12% of overall primary discharge diagnoses of stroke cases, and 26% of confirmed stroke who underwent CTA. CONCLUSION: Establishing the volume of acute CTAs and rates of LVO and thrombectomy when compared to suspected AIS on admission, confirmed stroke diagnoses who underwent CTA and primary discharge diagnosis of stroke is essential for the planning and provision of stroke services worldwide.


Asunto(s)
Arteriopatías Oclusivas/diagnóstico por imagen , Isquemia Encefálica/diagnóstico por imagen , Angiografía Cerebral/métodos , Angiografía por Tomografía Computarizada/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Trombectomía/estadística & datos numéricos , Arteriopatías Oclusivas/cirugía , Isquemia Encefálica/cirugía , Circulación Cerebrovascular , Femenino , Humanos , Irlanda , Masculino , Estudios Retrospectivos , Accidente Cerebrovascular/cirugía
13.
BMC Evol Biol ; 18(1): 193, 2018 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-30547744

RESUMEN

BACKGROUND: Obligate pollination mutualisms (OPMs) are specialized interactions in which female pollinators transport pollen between the male and female flowers of a single plant species and then lay eggs into those same flowers. The pollinator offspring hatch and feed upon some or all of the developing ovules pollinated by their mothers. Strong trait matching between plants and their pollinators in OPMs is expected to result in reciprocal partner specificity i.e., a single pollinator species using a single plant species and vice versa, and strict co-speciation. These issues have been studied extensively in figs and fig wasps, but little in the more recently discovered co-diversification of Epicephala moths and their Phyllanthaceae hosts. OPMs involving Epicephala moths are believed occur in approximately 500 species of Phyllanthaceae, making it the second largest OPM group after the Ficus radiation (> 750 species). In this study, we used a mixture of DNA barcoding, genital morphology and behavioral observations to determine the number of Epicephala moth species inhabiting the fruits of Breynia oblongifolia, their geographic distribution, pollinating behavior and phylogenetic relationships. RESULTS: We found that B. oblongifolia hosts two species of pollinator that co-occurred at all study sites, violating the assumption of reciprocal specificity. Male and female genital morphologies both differed considerably between the two moth species. In particular, females differed in the shape of their ovipositors, eggs and oviposition sites. Phylogenetic analyses indicated that the two Epicephala spp. on B. oblongifolia likely co-exist due to a host switch. In addition, we discovered that Breynia fruits are also often inhabited by a third moth, an undescribed species of Herpystis, which is a non-pollinating seed parasite. CONCLUSIONS: Our study reveals new complexity in interactions between Phyllantheae and Epicephala pollinators and highlights that host switching, co-speciation and non-pollinating seed parasites can shape species interactions in OPMs. Our finding that co-occurring Epicephala species have contrasting oviposition modes parallels other studies and suggests that such traits are important in Epicephala species coexistence.


Asunto(s)
Malpighiaceae/parasitología , Parásitos/fisiología , Polinización/fisiología , Animales , Teorema de Bayes , Código de Barras del ADN Taxonómico , Femenino , Geografía , Masculino , Mariposas Nocturnas/anatomía & histología , Mariposas Nocturnas/fisiología , Mariposas Nocturnas/ultraestructura , Nueva Gales del Sur , Ovario/citología , Oviposición , Óvulo Vegetal/citología , Parásitos/anatomía & histología , Parásitos/ultraestructura , Filogenia , Especificidad de la Especie
14.
Neuroradiology ; 60(10): 995-1012, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30097693

RESUMEN

Central or neurogenic diabetes insipidus (CDI) is due to deficient synthesis or secretion of antidiuretic hormone (ADH), also known as arginine vasopressin peptide (AVP). It is clinically characterised by polydipsia and polyuria (urine output > 30 mL/kg/day) of dilute urine (< 250 mOsm/L). It is the result of a defect in one of more sites involving the hypothalamic osmoreceptors, supraoptic or paraventricular nuclei of the hypothalamus, median eminence of the hypothalamus, infundibulum or the posterior pituitary gland. A focused MRI pituitary gland or sella protocol is essential. There are several neuroimaging correlates and causes of CDI, illustrated in this review. The most common causes are benign or malignant neoplasms of the hypothalamic-pituitary axis (25%), surgery (20%), head trauma (16%) or familial causes (10%). No cause is identified in up to 30% of cases. Knowledge of the anatomy and physiology of the hypothalamo-neurohypophyseal axis is crucial when evaluating a patient with CDI. Establishing the aetiology of CDI with MRI in combination with clinical and biochemical assessment facilitates appropriate targeted treatment. The aim of the pictorial review is to illustrate the wide variety of causes of CDI on neuroimaging, highlight the optimal MRI protocol and to revise the detailed neuroanatomy and neurophysiology required to interpret these studies.


Asunto(s)
Diabetes Insípida Neurogénica/diagnóstico por imagen , Diabetes Insípida Neurogénica/etiología , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Humanos , Sistema Hipotálamo-Hipofisario/anatomía & histología , Sistema Hipotálamo-Hipofisario/fisiología
15.
Oecologia ; 187(3): 811-823, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29704063

RESUMEN

A trend of increasing woody plant density, or woody thickening, has been observed across grassland and woodland ecosystems globally. It has been proposed that increasing atmospheric [CO2] is a major driver of broad scale woody thickening, though few field-based experiments have tested this hypothesis. Our study utilises a Free Air CO2 Enrichment experiment to examine the effect of elevated [CO2] (eCO2) on three mechanisms that can cause woody thickening, namely (i) woody plant recruitment, (ii) seedling growth, and (iii) post-disturbance resprouting. The study took place in a eucalypt-dominated temperate grassy woodland. Annual assessments show that juvenile woody plant recruitment occurred over the first 3 years of CO2 fumigation, though eCO2 did not affect rates of recruitment. Manipulative experiments were established to examine the effect of eCO2 on above-ground seedling growth using transplanted Eucalyptus tereticornis (Myrtaceae) and Hakea sericea (Proteaceae) seedlings. There was no positive effect of eCO2 on biomass of either species following 12 months of exposure to treatments. Lignotubers (i.e., resprouting organs) of harvested E. tereticornis seedlings that were retained in situ for an additional year were used to examine resprouting response. The likelihood of resprouting and biomass of resprouts increased with lignotuber volume, which was not itself affected by eCO2. The presence of herbaceous competitors and defoliation by invertebrates and pathogens were found to greatly reduce growth and/or resprouting response of seedlings. Our findings do not support the hypothesis that future increases in atmospheric [CO2] will, by itself, promote woody plant recruitment in eucalypt-dominated temperate grassy woodlands.


Asunto(s)
Herbivoria , Plantones , Dióxido de Carbono , Ecosistema , Bosques , Suelo
16.
J Intern Med ; 282(6): 537-545, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28875550

RESUMEN

BACKGROUND AND OBJECTIVES: Benefit from endovascular thrombectomy (EVT) for large-vessel occlusion (LVO) acute ischaemic stroke (AIS) is well demonstrated. Furthermore, emerging evidence supports efficacy in appropriately selected patients treated beyond current recommendations of 6 h. We evaluated clinical outcomes in patients undergoing late EVT at our institution. METHODS: Retrospective review of prospectively collected clinical database on 355 patients who underwent EVT for LVO AIS. Data collected consisted of patient demographics, radiological findings and outcome details. Outcomes, including 90-day functional status, recanalization, symptomatic intracranial haemorrhage (sICH) and 90-day mortality, for patients undergoing EVT <6 h, >6 h, and >7.3 h, were compared. RESULTS: A total of 355 patients underwent EVT for LVO AIS at our institution during the review period, with 74 (21%) patients treated ≥6 h from symptom onset. Successful recanalization was achieved in 285 (80%) patients, with 228 (81%) achieving a mTICI ≥2b in the <6 h group, and 57 (77%) in the >6 h group (P = 0.429). Ninety-day functional independence (mRS 0-2) was achieved in 162 (46%) patients, with 130 (46%) achieving a mRS of 0-2 in the <6 h group, and 32 (43%) in the >6 h group (P = 0.643). No significant differences were found in rates of sICH or 90-day mortality. No significant differences in functional independence, recanalization rates, sICH or mortality were identified in patients treated with EVT >7.3 h compared to <7.3 h. CONCLUSIONS: In appropriately selected patients, EVT >6 h was associated with comparable outcomes to those treated <6 h. These data support a physiological approach to patient selection.


Asunto(s)
Isquemia Encefálica/terapia , Procedimientos Endovasculares , Accidente Cerebrovascular/terapia , Trombectomía , Anciano , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/mortalidad , Procedimientos Endovasculares/métodos , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Selección de Paciente , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/mortalidad , Trombectomía/métodos , Factores de Tiempo , Resultado del Tratamiento
17.
Ir J Med Sci ; 186(2): 381-386, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-26860116

RESUMEN

BACKGROUND: Mid-trimester loss (MTL) is an area that is poorly defined in the literature and often under reported in clinical practice. The prevalence of MTL in Ireland is uncertain and has a huge impact on the woman, her family and maternity care services. AIMS: To explore the prevalence and patterns of care for women with MTL in a large Maternity hospital in Ireland. METHODS: A descriptive, exploratory study was used involving a retrospective chart audit. RESULTS: 220 women presented with MTL over the 3 year data collection period (January 2011-December 2013), giving a rate of 0.8 % of all deliveries. The majority of women had no previous pregnancy losses and were multiparous (i.e., had a previous pregnancy >500 g). The mean gestational age was 17.69 weeks (SD = 2.73). The mean length of hospital stay was 1.89 days. Intra muscular (IM) analgesia was the most commonly (58.5 %) used medication. Follow up hospital care was received in over 78 % of cases. The majority of women were referred the CMS Bereavement and Chaplain services, with a small number (approx. 5 %) referred to the social worker. Over 46.4 % of families availed of the hospital burial service. CONCLUSIONS: Results suggest the incidence of mid-trimester loss may be slightly lower than the 1 or 2 % of pregnancies reported in the literature. The incidence of mid-trimester loss in multiparous women is approximately twice that of nulliparous women. The referral services offered in the study were utilised by most of the women, as were follow-up clinic appointments.


Asunto(s)
Aborto Espontáneo/epidemiología , Edad Gestacional , Adulto , Femenino , Humanos , Irlanda , Embarazo , Prevalencia , Estudios Retrospectivos
18.
Neuroscience ; 315: 91-103, 2016 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-26701294

RESUMEN

Circadian rhythms in mammals are regulated by a system of circadian oscillators that includes a light-entrainable pacemaker in the suprachiasmatic nucleus (SCN) and food-entrainable oscillators (FEOs) elsewhere in the brain and body. In nocturnal rodents, the SCN promotes sleep in the day and wake at night, while FEOs promote an active state in anticipation of a predictable daily meal. For nocturnal animals to anticipate a daytime meal, wake-promoting signals from FEOs must compete with sleep-promoting signals from the SCN pacemaker. One hypothesis is that FEOs impose a daily rhythm of inhibition on SCN output that is timed to permit the expression of activity prior to a daytime meal. This hypothesis predicts that SCN activity should decrease prior to the onset of anticipatory activity and remain suppressed through the scheduled mealtime. To assess the hypothesis, neural activity in the SCN of mice anticipating a 4-5-h daily meal in the light period was measured using FOS immunohistochemistry and in vivo multiple unit electrophysiology. SCN FOS, quantified by optical density, was significantly reduced at the expected mealtime in food-anticipating mice with access to a running disk, compared to ad libitum-fed and acutely fasted controls. Group differences were not significant when FOS was quantified by other methods, or in mice without running disks. SCN electrical activity was markedly decreased during locomotion in some mice but increased in others. Changes in either direction were concurrent with locomotion, were not specific to food anticipation, and were not sustained during longer pauses. Reduced FOS indicates a net suppression of SCN activity that may depend on the intensity or duration of locomotion. The timing of changes in SCN activity relative to locomotion suggests that any effect of FEOs on SCN output is mediated indirectly, by feedback from neural or systemic correlates of locomotion.


Asunto(s)
Anticipación Psicológica/fisiología , Relojes Circadianos/fisiología , Ingestión de Alimentos/fisiología , Neuronas/metabolismo , Núcleo Supraquiasmático/fisiología , Actigrafía , Animales , Ingestión de Alimentos/psicología , Electrodos Implantados , Alimentos , Inmunohistoquímica , Masculino , Ratones Endogámicos C57BL , Actividad Motora/fisiología , Fotoperiodo , Proteínas Proto-Oncogénicas c-fos/metabolismo
19.
Clin Radiol ; 70(12): 1408-13, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26385204

RESUMEN

AIM: To report the experience of a regional stroke referral service with endovascular treatment for patients with acute ischaemic stroke (AIS) and large vessel occlusion. MATERIALS AND METHODS: A prospective review was undertaken of 93 consecutive cases receiving endovascular treatment for AIS over a 42-month period (January 2010 to June 2013). The National Institutes of Health Stroke Scale (NIHSS), location of large vessel occlusion, details of endovascular procedure, and degree of reperfusion achieved (Thrombolysis In Cerebral Infarction [TICI] score) were recorded. Mortality and functional outcome (modified Rankin Scale [mRS]) were measured at 90 days. RESULTS: The mean patient age was 62 years (range 26-87 years). The mean NIHSS at presentation was 16 (range 6-29). All patients had confirmed proximal large-artery occlusion on computed tomography (CT) angiography: 87 in the anterior circulation, six in the posterior circulation. Of the 93 patients treated, 64 (69%) received intravenous thrombolysis. Successful reperfusion (TICI grade 2a to 3) was achieved in 80 (86%) cases. There were 13 (14%) cases of failed vessel recanalisation (TICI grade 0). Good functional outcome (mRS ≤2) was achieved in 51 (55%) cases. The 90-day mortality was 20 (22%) cases. Fifty-seven (61%) cases were transferred from outside centres. There was no significant increase in morbidity or mortality for transferred patients. CONCLUSION: Successful endovascular recanalisation can result in good functional outcomes for patients with AIS and large vessel occlusion. Our interventional neuroradiology service provides endovascular treatment as part of a regional stroke service without increase in morbidity or mortality for patients transferred from outside institutions.


Asunto(s)
Arteriopatías Oclusivas/cirugía , Isquemia Encefálica/cirugía , Procedimientos Endovasculares , Stents , Accidente Cerebrovascular/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Arteriopatías Oclusivas/complicaciones , Arteriopatías Oclusivas/diagnóstico por imagen , Isquemia Encefálica/complicaciones , Isquemia Encefálica/diagnóstico por imagen , Angiografía Cerebral , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
20.
AJNR Am J Neuroradiol ; 36(5): 863-70, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25572952

RESUMEN

BACKGROUND AND PURPOSE: Hereditary hemorrhagic telangiectasia is an autosomal dominant disease that presents in 10%-20% of patients with various brain vascular malformations. We aimed to report the radiologic features (phenotype) and the genotype-phenotype correlations of brain vascular malformations in hereditary hemorrhagic telangiectasia. MATERIALS AND METHODS: Demographic, clinical, genotypic, and imaging information of 75 patients with hereditary hemorrhagic telangiectasia with brain arteriovenous malformations enrolled in the Brain Vascular Malformation Consortium from 2010 to 2012 were reviewed. RESULTS: Nonshunting, small, superficially located conglomerates of enhancing vessels without enlarged feeding arteries or draining veins called "capillary vascular malformations" were the most commonly observed lesion (46 of 75 patients; 61%), followed by shunting "nidus-type" brain AVMs that were typically located superficially with a low Spetzler-Martin Grade and a small size (32 of 75 patients; 43%). Direct high-flow fistulous arteriovenous shunts were present in 9 patients (12%). Other types of vascular malformations (dural AVF and developmental venous anomalies) were present in 1 patient each. Multiplicity of vascular malformations was seen in 33 cases (44%). No statistically significant correlation was observed between hereditary hemorrhagic telangiectasia gene mutation and lesion type or lesion multiplicity. CONCLUSIONS: Depending on their imaging features, brain vascular malformations in hereditary hemorrhagic telangiectasia can be subdivided into brain AVF, nidus-type AVM, and capillary vascular malformations, with the latter being the most common phenotype in hereditary hemorrhagic telangiectasia. No genotype-phenotype correlation was observed among patients with this condition.


Asunto(s)
Estudios de Asociación Genética , Malformaciones Arteriovenosas Intracraneales/diagnóstico por imagen , Malformaciones Arteriovenosas Intracraneales/genética , Telangiectasia Hemorrágica Hereditaria/diagnóstico por imagen , Telangiectasia Hemorrágica Hereditaria/genética , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía
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