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1.
BMJ Open ; 13(8): e075187, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37558454

RESUMO

INTRODUCTION: The top research priority for cavernoma, identified by a James Lind Alliance Priority setting partnership was 'Does treatment (with neurosurgery or stereotactic radiosurgery) or no treatment improve outcome for people diagnosed with a cavernoma?' This pilot randomised controlled trial (RCT) aims to determine the feasibility of answering this question in a main phase RCT. METHODS AND ANALYSIS: We will perform a pilot phase, parallel group, pragmatic RCT involving approximately 60 children or adults with mental capacity, resident in the UK or Ireland, with an unresected symptomatic brain cavernoma. Participants will be randomised by web-based randomisation 1:1 to treatment with medical management and with surgery (neurosurgery or stereotactic radiosurgery) versus medical management alone, stratified by prerandomisation preference for type of surgery. In addition to 13 feasibility outcomes, the primary clinical outcome is symptomatic intracranial haemorrhage or new persistent/progressive focal neurological deficit measured at 6 monthly intervals. An integrated QuinteT Recruitment Intervention (QRI) evaluates screening logs, audio recordings of recruitment discussions, and interviews with recruiters and patients/parents/carers to identify and address barriers to participation. A Patient Advisory Group has codesigned the study and will oversee its progress. ETHICS AND DISSEMINATION: This study was approved by the Yorkshire and The Humber-Leeds East Research Ethics Committee (21/YH/0046). We will submit manuscripts to peer-reviewed journals, describing the findings of the QRI and the Cavernomas: A Randomised Evaluation (CARE) pilot trial. We will present at national specialty meetings. We will disseminate a plain English summary of the findings of the CARE pilot trial to participants and public audiences with input from, and acknowledgement of, the Patient Advisory Group. TRIAL REGISTRATION NUMBER: ISRCTN41647111.


Assuntos
Neurocirurgia , Radiocirurgia , Adulto , Criança , Humanos , Estudos de Viabilidade , Projetos Piloto , Encéfalo , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
JAMA ; 327(19): 1875-1887, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35579641

RESUMO

Importance: Transcatheter aortic valve implantation (TAVI) is a less invasive alternative to surgical aortic valve replacement and is the treatment of choice for patients at high operative risk. The role of TAVI in patients at lower risk is unclear. Objective: To determine whether TAVI is noninferior to surgery in patients at moderately increased operative risk. Design, Setting, and Participants: In this randomized clinical trial conducted at 34 UK centers, 913 patients aged 70 years or older with severe, symptomatic aortic stenosis and moderately increased operative risk due to age or comorbidity were enrolled between April 2014 and April 2018 and followed up through April 2019. Interventions: TAVI using any valve with a CE mark (indicating conformity of the valve with all legal and safety requirements for sale throughout the European Economic Area) and any access route (n = 458) or surgical aortic valve replacement (surgery; n = 455). Main Outcomes and Measures: The primary outcome was all-cause mortality at 1 year. The primary hypothesis was that TAVI was noninferior to surgery, with a noninferiority margin of 5% for the upper limit of the 1-sided 97.5% CI for the absolute between-group difference in mortality. There were 36 secondary outcomes (30 reported herein), including duration of hospital stay, major bleeding events, vascular complications, conduction disturbance requiring pacemaker implantation, and aortic regurgitation. Results: Among 913 patients randomized (median age, 81 years [IQR, 78 to 84 years]; 424 [46%] were female; median Society of Thoracic Surgeons mortality risk score, 2.6% [IQR, 2.0% to 3.4%]), 912 (99.9%) completed follow-up and were included in the noninferiority analysis. At 1 year, there were 21 deaths (4.6%) in the TAVI group and 30 deaths (6.6%) in the surgery group, with an adjusted absolute risk difference of -2.0% (1-sided 97.5% CI, -∞ to 1.2%; P < .001 for noninferiority). Of 30 prespecified secondary outcomes reported herein, 24 showed no significant difference at 1 year. TAVI was associated with significantly shorter postprocedural hospitalization (median of 3 days [IQR, 2 to 5 days] vs 8 days [IQR, 6 to 13 days] in the surgery group). At 1 year, there were significantly fewer major bleeding events after TAVI compared with surgery (7.2% vs 20.2%, respectively; adjusted hazard ratio [HR], 0.33 [95% CI, 0.24 to 0.45]) but significantly more vascular complications (10.3% vs 2.4%; adjusted HR, 4.42 [95% CI, 2.54 to 7.71]), conduction disturbances requiring pacemaker implantation (14.2% vs 7.3%; adjusted HR, 2.05 [95% CI, 1.43 to 2.94]), and mild (38.3% vs 11.7%) or moderate (2.3% vs 0.6%) aortic regurgitation (adjusted odds ratio for mild, moderate, or severe [no instance of severe reported] aortic regurgitation combined vs none, 4.89 [95% CI, 3.08 to 7.75]). Conclusions and Relevance: Among patients aged 70 years or older with severe, symptomatic aortic stenosis and moderately increased operative risk, TAVI was noninferior to surgery with respect to all-cause mortality at 1 year. Trial Registration: isrctn.com Identifier: ISRCTN57819173.


Assuntos
Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/etiologia , Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/cirurgia , Feminino , Próteses Valvulares Cardíacas , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/métodos , Implante de Prótese de Valva Cardíaca/mortalidade , Humanos , Masculino , Fatores de Risco , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/mortalidade , Resultado do Tratamento
3.
J Neurosurg ; : 1-13, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35276651

RESUMO

OBJECTIVE: The aim of this study was to describe the processes and outcomes associated with patients at five sites in the Adult Hydrocephalus Clinical Research Network (AHCRN) who had undergone evaluation and treatment for suspected idiopathic normal pressure hydrocephalus (iNPH) and had 1-year postoperative follow-up. METHODS: Subjects with possible iNPH who had been prospectively enrolled in the AHCRN registry between November 19, 2014, and December 31, 2018, were evaluated by CSF drainage via either lumbar puncture or external lumbar drainage, consistent with recommendations of the international iNPH guidelines. Standardized clinical evaluations of gait, cognition, urinary symptoms, depression, and functional outcomes were conducted at baseline, before and after CSF drainage, and at 4-month intervals after shunt surgery. Complications of CSF drainage and shunt surgery were recorded. RESULTS: Seventy-four percent (424/570) of patients with possible iNPH had CSF drainage, and 46% of them (193/424) underwent shunt surgery. The mean change in gait velocity with CSF drainage was 0.18 m/sec in patients who underwent shunt surgery versus 0.08 m/sec in patients who did not. For shunt surgery patients, gait velocity increased by 54% from 0.67 m/sec before CSF drainage to 0.96 m/sec 8-12 months after surgery, and 80% of patients had an increase of at least 0.1 m/sec by the first postoperative visit. Evaluation of cognition, urinary symptoms, depression, and functional outcomes also revealed improvement after shunt surgery. Of 193 patients who had undergone shunt surgery, 176 (91%) had no complications and 17 (9%) had 28 complications. Eleven patients (6%) had 14 serious complications that resulted in the need for surgery or an extended hospital stay. The 30-day reoperation rate was 3%. CONCLUSIONS: Using criteria recommended by the international iNPH guidelines, the authors found that evaluation and treatment of iNPH are safe and effective. Testing with CSF drainage and treatment with shunt surgery are associated with a high rate of sustained improvement and a low rate of complications for iNPH in the 1st year after shunt surgery. Patients who had undergone shunt surgery for iNPH experienced improvement in gait, cognitive function, bladder symptoms, depression, and functional outcome measures. Gait velocity, which is an easily measured, objective, continuous variable, should be used as a standard outcome measure to test a patient's response to CSF drainage and shunt surgery in iNPH.

4.
Sci Rep ; 12(1): 177, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997137

RESUMO

Cerebellar damage during posterior fossa surgery in children can lead to ataxia and risk of cerebellar mutism syndrome. Compartmentalisation of sensorimotor and cognitive functions within the cerebellum have been demonstrated in animal electrophysiology and human imaging studies. Electrophysiological monitoring was carried out under general anaesthesia to assess the limb sensorimotor representation within the human cerebellum for assessment of neurophysiological integrity to reduce the incidence of surgical morbidities. Thirteen adult and paediatric patients undergoing posterior fossa surgery were recruited. Sensory evoked field potentials were recorded in response to mapping (n = 8) to electrical stimulation of limb nerves or muscles. For motor mapping (n = 5), electrical stimulation was applied to the surface of the cerebellum and evoked EMG responses were sought in facial and limb muscles. Sensory evoked potentials were found in two patients (25%). Responses were located on the surface of the right inferior posterior cerebellum to stimulation of the right leg in one patient, and on the left inferior posterior lobe in another patient to stimulation of left forearm. No evoked EMG responses were found for the motor mapping. The present study identifies challenges with using neurophysiological methods to map functional organization within the human cerebellum and considers ways to improve success.


Assuntos
Mapeamento Encefálico , Cerebelo/fisiologia , Craniotomia , Potencial Evocado Motor , Potenciais Somatossensoriais Evocados , Extremidades/inervação , Monitorização Neurofisiológica Intraoperatória , Contração Muscular , Músculo Esquelético/inervação , Adolescente , Adulto , Anestesia Geral , Criança , Pré-Escolar , Craniotomia/efeitos adversos , Estimulação Elétrica , Eletroencefalografia , Eletromiografia , Músculos Faciais/inervação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Adulto Jovem
5.
Br J Neurosurg ; 35(3): 285-291, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32643967

RESUMO

BACKGROUND: When appropriately selected, a high proportion of patients with suspected idiopathic normal pressure hydrocephalus (iNPH) will respond to cerebrospinal fluid diversion with a shunt. Extended lumbar drainage (ELD) is regarded as the most accurate test for this condition, however, varying estimates of its accuracy are found in the current literature. Here, we review the literature in order to provide summary estimates of sensitivity, specificity, positive- and negative predictive value for this test through meta-analysis of suitably rigorous studies. METHODS: Studies involving a population of NPH patients with predominantly idiopathic aetiology (>80%) in which the intention of the study was to shunt patients regardless of the outcome of ELD were included in the review. Various literature databases were searched to identify diagnostic test accuracy studies addressing ELD in the diagnosis of iNPH. Those studies passing screening and eligibility were assessed using the QUADAS-2 tool and data extracted for bivariate random effects meta-analysis. RESULTS: Four small studies were identified. They showed disparate results concerning diagnostic test accuracy. The summary estimates for sensitivity and specificity were 94% (CI 41-100%) and 85% (CI 33-100%), respectively. The summary estimates of positive and negative predictive value were both 90% (CIs 65-100% and 48-100%, respectively). CONCLUSION: Large, rigorous studies addressing the diagnostic accuracy of ELD are lacking, and little robust evidence exists to support the use of ELD in diagnostic algorithms for iNPH. Therefore, a large cohort study, or ideally an RCT, is needed to determine best practice in selecting patients for shunt surgery.


Assuntos
Hidrocefalia de Pressão Normal , Derivações do Líquido Cefalorraquidiano , Estudos de Coortes , Testes Diagnósticos de Rotina , Drenagem , Humanos , Hidrocefalia de Pressão Normal/diagnóstico , Hidrocefalia de Pressão Normal/cirurgia , Valor Preditivo dos Testes
6.
Environ Microbiol ; 23(7): 3646-3664, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33140504

RESUMO

Actinobacteria and Proteobacteria are important producers of bioactive natural products (NP), and these phyla dominate in the arid soils of Antarctica, where metabolic adaptations influence survival under harsh conditions. Biosynthetic gene clusters (BGCs) which encode NPs, are typically long and repetitious high G + C regions difficult to sequence with short-read technologies. We sequenced 17 Antarctic soil bacteria from multi-genome libraries, employing the long-read PacBio platform, to optimize capture of BGCs and to facilitate a comprehensive analysis of their NP capacity. We report 13 complete bacterial genomes of high quality and contiguity, representing 10 different cold-adapted genera including novel species. Antarctic BGCs exhibited low similarity to known compound BGCs (av. 31%), with an abundance of terpene, non-ribosomal peptide and polyketide-encoding clusters. Comparative genome analysis was used to map BGC variation between closely related strains from geographically distant environments. Results showed the greatest biosynthetic differences to be in a psychrotolerant Streptomyces strain, as well as a rare Actinobacteria genus, Kribbella, while two other Streptomyces spp. were surprisingly similar to known genomes. Streptomyces and Kribbella BGCs were predicted to encode antitumour, antifungal, antibacterial and biosurfactant-like compounds, and the synthesis of NPs with antibacterial, antifungal and surfactant properties was confirmed through bioactivity assays.


Assuntos
Produtos Biológicos , Streptomyces , Regiões Antárticas , Genômica , Filogenia , Solo
7.
Gigascience ; 9(4)2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32236524

RESUMO

BACKGROUND: The German Shepherd Dog (GSD) is one of the most common breeds on earth and has been bred for its utility and intelligence. It is often first choice for police and military work, as well as protection, disability assistance, and search-and-rescue. Yet, GSDs are well known to be susceptible to a range of genetic diseases that can interfere with their training. Such diseases are of particular concern when they occur later in life, and fully trained animals are not able to continue their duties. FINDINGS: Here, we provide the draft genome sequence of a healthy German Shepherd female as a reference for future disease and evolutionary studies. We generated this improved canid reference genome (CanFam_GSD) utilizing a combination of Pacific Bioscience, Oxford Nanopore, 10X Genomics, Bionano, and Hi-C technologies. The GSD assembly is ∼80 times as contiguous as the current canid reference genome (20.9 vs 0.267 Mb contig N50), containing far fewer gaps (306 vs 23,876) and fewer scaffolds (429 vs 3,310) than the current canid reference genome CanFamv3.1. Two chromosomes (4 and 35) are assembled into single scaffolds with no gaps. BUSCO analyses of the genome assembly results show that 93.0% of the conserved single-copy genes are complete in the GSD assembly compared with 92.2% for CanFam v3.1. Homology-based gene annotation increases this value to ∼99%. Detailed examination of the evolutionarily important pancreatic amylase region reveals that there are most likely 7 copies of the gene, indicative of a duplication of 4 ancestral copies and the disruption of 1 copy. CONCLUSIONS: GSD genome assembly and annotation were produced with major improvement in completeness, continuity, and quality over the existing canid reference. This resource will enable further research related to canine diseases, the evolutionary relationships of canids, and other aspects of canid biology.


Assuntos
Cromossomos/genética , Genoma/genética , Análise de Sequência de DNA/métodos , Sequenciamento Completo do Genoma/métodos , Animais , Cães , Genômica , Anotação de Sequência Molecular
8.
World Neurosurg ; 139: e32-e37, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32169618

RESUMO

BACKGROUND: Test balloon occlusion (TBO) is important in the management of complex cerebrovascular and skull base lesions when permanent occlusion (PO) of a parent artery may be indicated. Several adjuncts may be used to increase the sensitivity of TBO to predict whether PO will be tolerated. This is an observational study to evaluate the utility of internal carotid artery (ICA) TBO using single photon emission computed tomography (SPECT) scan in the management of complex vascular pathology and skull base tumors. METHODS: All TBO procedures performed over a 20-year period were analyzed. Clinical assessment and angiographic collateral flow were combined with semi-quantitative cerebral blood flow analysis using 99mTc hexamethylpropylene-amine oxime SPECT scan during ICA TBO. Evaluation of collateral circulation after TBO, and the complications of TBO and the safety of PO after successful TBO were evaluated. RESULTS: Eighty-three patients underwent TBO without complication. Of 45 patients with satisfactory TBO, 28 proceeded to PO. Three patients developed transient ischemic symptoms thought to be embolic in origin. Thirty-eight patients had unsatisfactory TBO, of whom 15 required PO accompanied by a bypass procedure. Forty patients in the series did not undergo permanent vessel occlusion. CONCLUSIONS: SPECT scan-enhanced TBO is an important component of the management of complex vascular pathology and skull base tumors, permitting safe PO of the parent vessel and definitive treatment of the main pathology.


Assuntos
Oclusão com Balão/métodos , Encéfalo/diagnóstico por imagem , Artéria Carótida Interna/cirurgia , Aneurisma Intracraniano/cirurgia , Cuidados Pré-Operatórios/métodos , Neoplasias da Base do Crânio/cirurgia , Encéfalo/irrigação sanguínea , Angiografia Cerebral , Circulação Cerebrovascular , Circulação Colateral , Humanos , Ligadura , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Tecnécio Tc 99m Exametazima , Tomografia Computadorizada de Emissão de Fóton Único
9.
Infect Agent Cancer ; 12: 46, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28811834

RESUMO

BACKGROUND: Although high risk HPVs are associated with an increased risk of prostate cancer it is not known if they have a causal role. The purpose of this study is to investigate the potential role of human papilloma viruses (HPVs) in prostate cancer. The aims are (i) to investigate the presence and confirm the identity of high risk HPVs in benign prostate tissues prior to the development of HPV positive prostate cancer in the same patients, and (ii) to determine if HPVs are biologically active. METHODS: We used polymerase chain reaction (PCR) to identify HPVs in specimens from 52 Australian men with benign prostate biopsies who 1 to 10 years later developed prostate cancer. Immunohistochemistry (IHC) was used to assess the expression of HPV E7 oncoproteins, cytokeratin and prostate specific antigen (PSA). We used RNASeq data from The Cancer Genome Atlas (TCGA) to identify possible HPV RNA sequences in prostate cancer. RESULTS: HPV screening using standard PCR was conducted on 28 of the 52 sets of benign and later prostate cancers. HPV L1 genes were identified in 13 (46%) benign and 8 (29%) of 28 later prostate cancers in the same patients. HPV E7 genes were identified in 23 (82%) benign and 19 (68%) of 28 subsequent prostate cancers in the same patients. The same HPV types were present in both the benign and subsequent prostate cancers in 9 sets of specimens. HPV type 16 was identified in 15% of benign and 3% of prostate cancers. HPV type 18 was identified in 26% of benign and 16% of prostate cancers. Small numbers of HPV types 45, 47, 76 and 115 were also identified. High confidence RNA-Seq evidence for high risk HPV types 16 and 18 was identified in 12 (2%) of the 502 TCGA prostate cancer transcriptomes. High risk HPV E7 oncoprotein was positively expressed in 23 (82%) of 28 benign prostate specimens but only in 8 (29%) of 28 of the later prostate cancer specimens. This difference is statistically significant (p = 0.001). Prostate specific antigen (PSA) was more highly expressed in 26 (50%) of 52 prostate cancer specimens as compared to prior benign prostate specimens in the same patients. CONCLUSIONS: High risk HPVs are present in benign prostate tissues prior to the development of HPV positive prostate cancer. There is a significantly higher expression of HPV E7 oncoproteins in benign prostate tissues as compared to late prostate cancer that subsequently developed in the same patients. This observation suggests that HPV oncogenic activity is an early phenomenon in a majority of prostate oncogenesis. TCGA RNA-Seq data suggests that HPV is biologically active in some prostate tumour samples.

10.
Drug Deliv ; 23(1): 167-73, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-24786643

RESUMO

CONTEXT: Inadequate penetration of the blood-brain barrier (BBB) by systemically administered chemotherapies including carboplatin is implicated in their failure to improve prognosis for patients with glioblastoma. Convection-enhanced delivery (CED) of carboplatin has the potential to improve outcomes by facilitating bypass of the BBB. OBJECTIVE: We report the first use of an implantable CED system incorporating a novel transcutaneous bone-anchored port (TBAP) for intermittent CED of carboplatin in a patient with recurrent glioblastoma. MATERIALS AND METHODS: The CED catheter system was implanted using a robot-assisted surgical method. Catheter targeting accuracy was verified by performing intra-operative O-arm imaging. The TBAP was implanted using a skin-flap dermatome technique modeled on bone-anchored hearing aid surgery. Repeated infusions were performed by attaching a needle administration set to the TBAP. Drug distribution was monitored with serial real-time T2-weighted magnetic resonance imaging (MRI). RESULTS: All catheters were implanted to within 1.5 mm of their planned target. Intermittent infusions of carboplatin were performed on three consecutive days and repeated after one month without the need for further surgical intervention. Infused volumes of 27.9 ml per day were well tolerated, with the exception of a single seizure episode. Follow-up MRI at eight weeks demonstrated a significant reduction in the volume of tumor enhancement from 42.6 ml to 24.6 ml, and was associated with stability of the patient's clinical condition. CONCLUSION: Reduction in the volume of tumor enhancement indicates that intermittent CED of carboplatin has the potential to improve outcomes in glioblastoma. The novel technology described in this report make intermittent CED infusion regimes an achievable treatment strategy.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Carboplatina/administração & dosagem , Carboplatina/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Glioblastoma/tratamento farmacológico , Administração Cutânea , Antineoplásicos/efeitos adversos , Carboplatina/efeitos adversos , Cateteres de Demora , Convecção , Epilepsia Generalizada/complicações , Feminino , Humanos , Infusões Intravenosas , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Robótica
11.
Br J Neurosurg ; 29(1): 110-111, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25311041

RESUMO

Anterograde amnesia is a recognised complication of colloid cyst excision, occurring usually as a result of forniceal injury. However, spontaneous amnesia due to intra-cyst haemorrhage prior to excision has not been reported previously. We report such a case in which amnesia completely resolved following endoscopic cyst excision.

12.
Eur J Paediatr Neurol ; 17(1): 36-44, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23183057

RESUMO

OBJECTIVES: The indications for surgery and outcomes of patients who underwent surgical removal of subependymal giant cell astrocytomas (SEGAs) in our institution between 2000 and 2011 were reviewed. METHODS: We reviewed the clinical details of 16 patients with a diagnosis of Tuberous Sclerosis Complex (TSC) who underwent surgery for SEGA in Bristol since 2000. We collected information on age, sex, epilepsy history and cognitive status. We reviewed the indications for surgery, age at surgery, surgical approach, and the size and location of the lesions. We analysed mortality, completeness of tumour resection, intraoperative blood transfusion, shunt placements, and surgical complications. RESULTS: 13 patients had surgery due to hydrocephalus. Increasing size of SEGA without hydrocephalus was an indication for surgery in two patients, and in one patient, the SEGA was removed because of its size and location at initial scan. 13 patients had complete tumour resection. One patient had tumour recurrence. Hydrocephalus failed to resolve or reoccurred in four patients post operatively necessitating shunt insertion. The surgical approach was transcortical in 14 patients and transcallosal in two. There was zero mortality in this series. There were no reports of cognitive decline or worsening epilepsy following surgery. CONCLUSION: Surgery is a safe and effective treatment for SEGA. It is the authors' view that surgery remains the most appropriate treatment strategy for SEGAs that are amenable to surgery. More work needs to be undertaken to assess prospectively the neurocognitive impact of surgery, and the relative advantages of different surgical approaches.


Assuntos
Astrocitoma/cirurgia , Neoplasias Encefálicas/cirurgia , Esclerose Tuberosa/complicações , Adolescente , Adulto , Astrocitoma/etiologia , Neoplasias Encefálicas/etiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Procedimentos Neurocirúrgicos , Estudos Retrospectivos , Adulto Jovem
13.
J Neurosurg ; 116(2): 445-52, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22098198

RESUMO

OBJECT: The evaluation of third ventriculostomy function in hydrocephalic patients is challenging. The utility of the constant flow infusion test in predicting response to shunt insertion in normal-pressure hydrocephalus, as well as in identifying shunt malfunction, has been previously demonstrated. The object of this study was to evaluate its usefulness in determining whether a revision CSF diversion procedure was indicated in patients presenting with recurring symptoms and persisting ventriculomegaly after endoscopic third ventriculostomy (ETV). METHODS: The authors conducted a prospective study of all patients who, after undergoing ETV at their institution, presented postoperatively with recurring symptoms and persisting ventriculomegaly. RESULTS: Forty-six patients (mean age 40.7 years, including 11 patients younger than 18 years) underwent 56 constant flow ventricular infusion tests (VITs) at a mean of 24.7 months post-ETV. Thirty-three patients with resistance to CSF outflow (R(out)) less than 13 mm Hg/ml/min underwent follow-up (median 17 months) and experienced resolution of symptoms. In 10 episodes R(out) was greater than 13 mm Hg/ml/min; the patients in these cases underwent revisional CSF diversion. Two patients demonstrated high and frequent B (slow) waves despite a low R(out); these patients also underwent successful revisions. Patients who improved after surgery had increased B wave activity in the plateau phase of the VIT (p = 0.01). Thirty-four patients underwent MR imaging at the same time; 4 had high R(out) despite evidence of flow across the stoma. These 4 patients underwent surgery and experienced resolution of symptoms. Of 9 patients without flow, R(out) was less than 13 mm Hg/ml/min in 4; these patients were successfully treated conservatively. CONCLUSIONS: The VIT is a useful and safe adjunct to clinical and MR imaging evaluation when ETV failure is suspected.


Assuntos
Hidrocefalia , Neuroendoscopia/métodos , Terceiro Ventrículo/fisiologia , Terceiro Ventrículo/cirurgia , Ventriculostomia/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Líquido Cefalorraquidiano/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Hidrocefalia/diagnóstico , Hidrocefalia/fisiopatologia , Hidrocefalia/cirurgia , Lactente , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/cirurgia , Estudos Prospectivos , Reoperação , Falha de Tratamento , Adulto Jovem
14.
Br J Neurosurg ; 25(5): 614-20, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21501048

RESUMO

OBJECTIVE: Brain biopsy is standard clinical practice when CNS malignancy is suspected. Its value has not otherwise been clearly established. We reviewed the indications for, complications and outcome of diagnostic brain biopsies performed between 2003 and 2008 in a single UK centre. METHODS: Subjects were retrospectively identified using theatre log books and histopathology reports. Case records were analysed by a neurologist and neurosurgeon. Cases were excluded when the pre-operative diagnosis was clearly malignancy or infection. RESULTS: Of all (432) brain biopsies performed, 56 were performed in 52 patients with cryptogenic neurological disease. There were no permanent deficits or deaths. Histopathological reports were classified as definitive (45%), suggestive (20%) or non-diagnostic (36%). Brain biopsy made an immediate contribution to determination of diagnosis in 55% (31 of 56) and a confident diagnosis was eventually made in 40 of 52 patients (77%). Management was altered as a consequence of biopsy in 63%. Successful biopsy of a radiologically identified target increased the proportion of biopsies considered diagnostic to 78% (odds ratio 8.9) whereas non-targeted biopsy was non-diagnostic in 71%. Although a significant proportion of patients died or had progressive disease, this was not uniformly the case; 31% stabilised and 27% improved. CONCLUSION: We present the highest reported frequency of brain biopsy for cryptogenic neurological disease. The risk associated with the procedure was low and the biopsy results impacted significantly upon diagnosis and management. We therefore propose that the procedure should no longer be considered one of last resort.


Assuntos
Biópsia , Encéfalo/patologia , Doenças do Sistema Nervoso Central/diagnóstico , Adolescente , Adulto , Idoso , Doenças do Sistema Nervoso Central/patologia , Doenças do Sistema Nervoso Central/terapia , Criança , Pré-Escolar , Diagnóstico Diferencial , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Reino Unido , Adulto Jovem
15.
Proteomics ; 10(15): 2790-800, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20486118

RESUMO

Integrins are transmembrane proteins regulating cellular shape, mobility and the cell cycle. A highly conserved signature motif in the cytoplasmic tail of the integrin alpha-subunit, KXGFFKR, plays a critical role in regulating integrin function. To date, six proteins have been identified that target this motif of the platelet-specific integrin alpha(IIb)beta(3). We employ peptide-affinity chromatography followed-up with LC-MS/MS analysis as well as protein chips to identify new potential regulators of integrin function in platelets and put them into their biological context using information from protein:protein interaction (PPI) databases. Totally, 44 platelet proteins bind with high affinity to an immobilized LAMWKVGFFKR-peptide. Of these, seven have been reported in the PPI literature as interactors with integrin alpha-subunits. 68 recombinant human proteins expressed on the protein chip specifically bind with high affinity to biotin-tagged alpha-integrin cytoplasmic peptides. Two of these proteins are also identified in the peptide-affinity experiments, one is also found in the PPI databases and a further one is present in the data to all three approaches. Finally, novel short linear interaction motifs are common to a number of proteins identified.


Assuntos
Plaquetas/metabolismo , Integrina alfa2/metabolismo , Mapeamento de Interação de Proteínas , Proteínas/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Cromatografia de Afinidade/métodos , Cromatografia Líquida , Humanos , Dados de Sequência Molecular , Peptídeos/metabolismo , Mapeamento de Interação de Proteínas/métodos , Espectrometria de Massas em Tandem
16.
Nat Chem Biol ; 3(2): 108-12, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17220901

RESUMO

Short synthetic oligopeptides based on regions of human proteins that encompass functional motifs are versatile reagents for understanding protein signaling and interactions. They can either mimic or inhibit the parent protein's activity and have been used in drug development. Peptide studies typically either derive peptides from a single identified protein or (at the other extreme) screen random combinatorial peptides, often without knowledge of the signaling pathways targeted. Our objective was to determine whether rational bioinformatic design of oligopeptides specifically targeted to potentially signaling-rich juxtamembrane regions could identify modulators of human platelet function. High-throughput in vitro platelet function assays of palmitylated cell-permeable oligopeptides corresponding to these regions identified many agonists and antagonists of platelet function. Many bioactive peptides were from adhesion molecules, including a specific CD226-derived inhibitor of inside-out platelet signaling. Systematic screens of this nature are highly efficient tools for discovering short signaling motifs in molecular signaling pathways.


Assuntos
Biologia Computacional/métodos , Oligopeptídeos/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Difosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/metabolismo , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Moléculas de Adesão Celular/genética , Análise por Conglomerados , Avaliação Pré-Clínica de Medicamentos , Humanos , Proteínas de Membrana/genética , Mimetismo Molecular/genética , Oligopeptídeos/química , Oligopeptídeos/genética , Ácido Palmítico/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/farmacologia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo
18.
J Neurosurg ; 102(2 Suppl): 224-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16156235

RESUMO

The authors report on the case of a diffuse pontine glioma in a 5-year-old boy in whom radiologically and cytologically occult leptomeningeal metastases led to the development of an atypical "external" hydrocephalus, associated with grossly elevated intracranial pressure (ICP). Initial neuroimaging demonstrated only mild communicating ventricular dilation associated with a noticeable enlargement of the subarachnoid space, particularly over the surface of the frontal lobes; these features are not usually associated with significantly elevated ICP. Possible pathophysiological mechanisms resulting in this unusual clinical presentation are discussed. Early recognition of the severity of the raised ICP despite the paucity of clinical and radiological signs may have averted the development of blindness due to optic atrophy.


Assuntos
Neoplasias do Tronco Encefálico/patologia , Glioblastoma/patologia , Hidrocefalia/diagnóstico , Hidrocefalia/fisiopatologia , Imageamento por Ressonância Magnética , Neoplasias Meníngeas/patologia , Biópsia , Neoplasias do Tronco Encefálico/radioterapia , Córtex Cerebral/patologia , Pré-Escolar , Diagnóstico Diferencial , Evolução Fatal , Lobo Frontal/patologia , Glioblastoma/radioterapia , Humanos , Hidrocefalia/complicações , Hipertensão Intracraniana/diagnóstico , Hipertensão Intracraniana/etiologia , Masculino , Neoplasias Meníngeas/radioterapia , Invasividade Neoplásica , Nervo Oculomotor/patologia , Atrofia Óptica/etiologia , Atrofia Óptica/patologia , Lesões por Radiação/complicações , Radioterapia/efeitos adversos , Punção Espinal , Espaço Subaracnóideo/patologia
19.
Circulation ; 109(24): 2986-92, 2004 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-15184289

RESUMO

BACKGROUND: The mechanisms underlying the variation in collateral formation between patients, even with similar patterns of coronary artery disease, remain unclear. This study investigates whether circulating humoral or cellular factors can provide an insight into this variation. METHODS AND RESULTS: Thirty patients with isolated left anterior descending coronary artery disease underwent percutaneous coronary intervention with collateral flow index (CFI) determined using a pressure wire. Patients with inadequate (CFI <0.25) compared with those with adequate (CFI > or =0.25) collateral support had, or tended to have, lower concentrations of coronary sinus growth factors and plasma exerting a weaker effect on endothelial cell migration and angiogenesis in vitro. However, there was an inverse correlation between serum mitogenicity and CFI (r=-0.61, P<0.01). No significant differences were detected between the 2 groups in plasma levels of total vascular endothelial growth factor, vascular endothelial growth factor165, or placental growth factor. There was a strong positive correlation between numbers of CD34/CD133-positive circulating hemopoietic precursor cells and CFI (r=0.75, P<0.001). In patients with inadequate, compared with those with adequate, CFI, the numbers of differentiated endothelial progenitor cells (EPCs) appearing in the circulation and in culture were significantly reduced by 75% (P<0.05) and 70% (P<0.05), respectively. CONCLUSIONS: In this study, inadequate coronary collateral development is associated with reduced numbers of circulating EPCs and impaired chemotactic and proangiogenic but not mitogenic activity. These findings are consistent with current efforts to enhance collateral formation by augmentation of circulating EPCs.


Assuntos
Circulação Coronária , Doença das Coronárias/sangue , Endotélio Vascular/patologia , Fator 2 de Crescimento de Fibroblastos/sangue , Células-Tronco Mesenquimais/citologia , Neovascularização Fisiológica , Proteínas da Gravidez/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Idoso , Antígenos de Diferenciação/análise , Cateterismo Cardíaco , Cateterismo , Movimento Celular , Células Cultivadas/metabolismo , Doença das Coronárias/patologia , Teste de Esforço , Feminino , Variação Genética , Humanos , Masculino , Células-Tronco Mesenquimais/química , Pessoa de Meia-Idade , Fator de Crescimento Placentário , Pressão , Estudos Prospectivos , Fatores de Risco , Método Simples-Cego , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise
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