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1.
AJNR Am J Neuroradiol ; 44(6): 634-640, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37169541

RESUMO

BACKGROUND AND PURPOSE: Surgical clipping and endovascular treatment are commonly used in patients with unruptured intracranial aneurysms. We compared the safety and efficacy of the 2 treatments in a randomized trial. MATERIALS AND METHODS: Clipping or endovascular treatments were randomly allocated to patients with one or more 3- to 25-mm unruptured intracranial aneurysms judged treatable both ways by participating physicians. The study hypothesized that clipping would decrease the incidence of treatment failure from 13% to 4%, a composite primary outcome defined as failure of aneurysm occlusion, intracranial hemorrhage during follow-up, or residual aneurysms at 1 year, as adjudicated by a core lab. Safety outcomes included new neurologic deficits following treatment, hospitalization of >5 days, and overall morbidity and mortality (mRS > 2) at 1 year. There was no blinding. RESULTS: Two hundred ninety-one patients were enrolled from 2010 to 2020 in 7 centers. The 1-year primary outcome, ascertainable in 290/291 (99%) patients, was reached in 13/142 (9%; 95% CI, 5%-15%) patients allocated to surgery and in 28/148 (19%; 95% CI, 13%-26%) patients allocated to endovascular treatments (relative risk: 2.07; 95% CI, 1.12-3.83; P = .021). Morbidity and mortality (mRS >2) at 1 year occurred in 3/143 and 3/148 (2%; 95% CI, 1%-6%) patients allocated to surgery and endovascular treatments, respectively. Neurologic deficits (32/143, 22%; 95% CI, 16%-30% versus 19/148, 12%; 95% CI, 8%-19%; relative risk: 1.74; 95% CI, 1.04-2.92; P = .04) and hospitalizations beyond 5 days (69/143, 48%; 95% CI, 40%-56% versus 12/148, 8%; 95% CI, 5%-14%; relative risk: 0.18; 95% CI, 0.11-0.31; P < .001) were more frequent after surgery. CONCLUSIONS: Surgical clipping is more effective than endovascular treatment of unruptured intracranial aneurysms in terms of the frequency of the primary outcome of treatment failure. Results were mainly driven by angiographic results at 1 year.


Assuntos
Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Resultado do Tratamento , Falha de Tratamento , Procedimentos Endovasculares/métodos , Embolização Terapêutica/métodos
2.
Nature ; 585(7824): 203-206, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908263

RESUMO

The dominant gaseous structure in the Galactic halo is the Magellanic Stream. This extended network of neutral and ionized filaments surrounds the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC), the two most massive satellite galaxies of the Milky Way1-4. Recent observations indicate that the LMC and SMC are on their first passage around the Galaxy5, that the Magellanic Stream is made up of gas stripped from both clouds2,6,7 and that the majority of this gas is ionized8,9. Although it has long been suspected that tidal forces10,11 and ram-pressure stripping12,13 contributed to the formation of the Magellanic Stream, models have not been able to provide a full understanding of its origins3. Several recent developments-including the discovery of dwarf galaxies associated with the Magellanic group14-16, determination of the high mass of the LMC17, detection of highly ionized gas near stars in the LMC18,19 and predictions of cosmological simulations20,21-support the existence of a halo of warm (roughly 500,000 kelvin) ionized gas around the LMC (the 'Magellanic Corona'). Here we report that, by including this Magellanic Corona in hydrodynamic simulations of the Magellanic Clouds falling onto the Milky Way, we can reproduce the Magellanic Stream and its leading arm. Our simulations explain the filamentary structure, spatial extent, radial-velocity gradient and total ionized-gas mass of the Magellanic Stream. We predict that the Magellanic Corona will be unambiguously observable via high-ionization absorption lines in the ultraviolet spectra of background quasars lying near the LMC.

3.
AJNR Am J Neuroradiol ; 38(3): 432-441, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28082261

RESUMO

BACKGROUND AND PURPOSE: Some patients are at high risk of aneurysm recurrence after endovascular treatment: patients with large aneurysms (Patients Prone to Recurrence After Endovascular Treatment PRET-1) or with aneurysms that have previously recurred after coiling (PRET-2). We aimed to establish whether the use of hydrogel coils improved efficacy outcomes compared with bare platinum coils. MATERIALS AND METHODS: PRET was an investigator-led, pragmatic, multicenter, parallel, randomized (1:1) trial. Randomized allocation was performed separately for patients in PRET-1 and PRET-2, by using a Web-based platform ensuring concealed allocation. The primary outcome was a composite of a residual/recurrent aneurysm, adjudicated by a blinded core laboratory, or retreatment, intracranial bleeding, or mass effect during the 18-month follow-up. Secondary outcomes included adverse events, mortality, and morbidity (mRS > 2). The hypothesis was that hydrogel would decrease the primary outcome from 50% to 30% at 18 months, necessitating 125 patients per group (500 for PRET-1 and PRET-2). RESULTS: The trial was stopped once 250 patients in PRET-1 and 197 in PRET-2 had been recruited because of slow accrual. A poor primary outcome occurred in 44.4% (95% CI, 35.5%-53.2%) of those in PRET-1 allocated to platinum compared with 52.5% (95% CI, 43.4%-61.6%) of patients allocated to hydrogel (OR, 1.387; 95% CI, 0.838-2.295; P = .20) and in 49.0% (95% CI, 38.8%-59.1%) in PRET-2 allocated to platinum compared with 42.1% (95% CI, 32.0%-52.2%) allocated to hydrogel (OR, 0.959; 95% CI, 0.428-1.342; P = .34). Adverse events and morbidity were similar. There were 3.6% deaths (1.4% platinum, 5.9% hydrogel; P = .011). CONCLUSIONS: Coiling of large and recurrent aneurysms is safe but often poorly effective according to angiographic results. Hydrogel coiling was not shown to be better than platinum.


Assuntos
Embolização Terapêutica/instrumentação , Procedimentos Endovasculares/instrumentação , Hidrogel de Polietilenoglicol-Dimetacrilato/uso terapêutico , Aneurisma Intracraniano/cirurgia , Adulto , Idoso , Aneurisma Roto/cirurgia , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Platina , Recidiva , Retratamento , Resultado do Tratamento
4.
AJNR Am J Neuroradiol ; 38(1): 213-214, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27884879
5.
AJNR Am J Neuroradiol ; 37(11): 2026-2032, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27313130

RESUMO

BACKGROUND AND PURPOSE: Signs suggestive of unexpected dural venous sinus thrombosis are detectable on routine MR imaging studies without MRV. We assessed performance characteristics and interrater reliability of routine MR imaging for the diagnosis of dural venous sinus thrombosis, focusing on the superior sagittal, transverse, and sigmoid sinuses. MATERIALS AND METHODS: This case series included 350 patients with MRIs performed with contrast-enhanced MRV and 79 patients with routine MRIs performed within 48 hours of a CTV from 2008 to 2014 (total, n = 429). Routine MR images were separated from the contrast-enhanced MRVs and CTVs. Three neuroradiologists, blinded to clinical data, independently reviewed the MRIs for signs of dural venous sinus thrombosis, including high signal on sagittal T1, loss of flow void on axial T2, high signal on FLAIR, high signal on DWI, increased susceptibility effects on T2*-weighted gradient recalled-echo imaging, and filling defects on axial contrast-enhanced spin-echo T1WI and/or volumetric gradient-echo T1WI. Two neuroradiologists independently reviewed contrast-enhanced MRVs and CTVs to determine the consensus gold standard. Interrater reliability was calculated by using the κ coefficient. RESULTS: Contrast-enhanced MRV and CTV confirmed that dural venous sinus thrombosis was present in 72 of 429 cases (16.8%). The combination of routine MR sequences had an overall sensitivity of 79.2%, specificity of 89.9%, and moderate interrater reliability (κ = 0.50). The 3 readers did not have similar performance characteristics. 69.4% of positive cases had clinical suspicion of dural venous sinus thrombosis indicated on imaging requisition. CONCLUSIONS: Routine MR images can suggest dural venous sinus thrombosis with high specificity in high-risk patients, even in cases without clinical suspicion.

6.
J Small Anim Pract ; 57(4): 210-3, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27000650

RESUMO

OBJECTIVES: To describe the morphologic and morphometric computed tomographic excretory urography features of intramural ectopic ureters in dogs. METHODS: Retrospective evaluation of computed tomographic excretory urography studies in 10 dogs with surgical and/or cystoscopically confirmed intramural ectopic ureters. All studies were assessed for ureteral ectopia, dilatation, tortuosity, ureterovesicular junction morphology and ureteral orifice location. RESULTS: A total of 14 intramural ectopic ureters were confirmed at surgery/cystoscopy with reviewers correctly identifying 100% (14/14). Abnormalities on computed tomographic excretory urography included ureteral dilatation (7), ureteral tortuosity (3), lack of a normal ureterovesicular junction (14), urethral ureteral orifice location (14) and lack of ureteral divergence (14). CLINICAL SIGNIFICANCE: Lack of a normal ureterovesicular junction, a urethral-ureteral orifice location and lack of ureteral divergence are common computed tomographic excretory urography findings in dogs with intramural ectopic ureters. This technique requires further investigation to determine whether it might allow differentiation of intramural and extramural ectopic ureters.


Assuntos
Coristoma/veterinária , Doenças do Cão/diagnóstico por imagem , Doenças Peritoneais/veterinária , Ureter , Animais , Cruzamento , Coristoma/diagnóstico por imagem , Cães , Feminino , Variações Dependentes do Observador , Doenças Peritoneais/diagnóstico por imagem , Estudos Retrospectivos , Distribuição por Sexo , Tomografia Computadorizada por Raios X/veterinária , Ureter/diagnóstico por imagem , Urografia/métodos , Urografia/veterinária
7.
AJNR Am J Neuroradiol ; 37(1): 2-10, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26316571

RESUMO

Carotid near-occlusion is distal ICA luminal collapse beyond a tight stenosis, where the distal lumen should not be used for calculating percentage stenosis. Near-occlusion with full ICA collapse is well-known, with a threadlike lumen. However, near-occlusion without collapse is often subtle and can be overlooked as a usual severe stenosis. More than 10 different terms have been used to describe near-occlusion, sometimes causing confusion. This systematic review presents what is known about carotid near-occlusion. In this first part, the foci are definition, terminology, and diagnosis.


Assuntos
Estenose das Carótidas/diagnóstico , Humanos
8.
AJNR Am J Neuroradiol ; 37(2): 200-4, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26338908

RESUMO

In Part 1 of this review, the definition, terminology, and diagnosis of carotid near-occlusion were presented. Carotid near-occlusions (all types) showed a lower risk of stroke than other severe stenoses. However, emerging evidence suggests that the near-occlusion prognosis with full collapse (higher risk) differs from that without full collapse (lower risk). This systematic review presents what is known about carotid near-occlusion. In this second part, the foci are prognosis and treatment, pathophysiology, the current confusion about near-occlusion, and areas in need of future improvement.


Assuntos
Estenose das Carótidas/diagnóstico , Estenose das Carótidas/fisiopatologia , Estenose das Carótidas/terapia , Humanos , Prognóstico
9.
AJNR Am J Neuroradiol ; 37(5): 879-84, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26659336

RESUMO

BACKGROUND AND PURPOSE: Patients treated with coiling are often followed by MR angiography. Our objective was to assess the inter- and intraobserver agreement in diagnosing aneurysm remnants and recurrences by using multimodality imaging, including TOF MRA. MATERIALS AND METHODS: A portfolio composed of 120 selected images from 56 patients was sent to 15 neuroradiologists from 10 institutions. For each case, raters were asked to classify angiographic results (3 classes) of 2 studies (32 MRA-MRA and 24 DSA-MRA pairs) and to provide a final judgment regarding the presence of a recurrence (no, minor, major). Six raters were asked to independently review the portfolio twice. A second study, restricted to 4 raters having full access to all images, was designed to validate the results of the electronic survey. RESULTS: The proportion of cases judged to have a major recurrence varied between 16.1% and 71.4% (mean, 35.0% ± 12.7%). There was moderate agreement overall (κ = 0.474 ± 0.009), increasing to nearly substantial (κ = 0.581 ± 0.014) when the judgment was dichotomized (presence or absence of a major recurrence). Agreement on cases followed-up by MRA-MRA was similarly substantial (κ = 0.601 ± 0.018). The intrarater agreement varied between fair (κ = 0.257 ± 0.093) and substantial (κ= 0.699 ± 0.084), improving with a dichotomized judgment concerning MRA-MRA comparisons. Agreement was no better when raters had access to all images. CONCLUSIONS: There is an important variability in the assessment of angiographic outcomes of endovascular treatments. Agreement on the presence of a major recurrence when comparing 2 MRA studies or the MRA with the last catheter angiographic study can be substantial.


Assuntos
Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Angiografia por Ressonância Magnética/métodos , Neuroimagem/métodos , Angiografia Digital/métodos , Embolização Terapêutica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Reprodutibilidade dos Testes , Resultado do Tratamento
10.
AJNR Am J Neuroradiol ; 35(8): 1551-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24948501

RESUMO

BACKGROUND AND PURPOSE: Anterior communicating artery aneurysms account for one-fourth of all intracranial aneurysms and frequently occur in the context of A1 vessel asymmetry. The purpose of this study was to correlate circle of Willis anatomic variation association to angiographic and clinical outcomes of anterior communicating aneurysm coiling. MATERIALS AND METHODS: The Cerecyte Coil Trial provides a subgroup of 124 cases with anterior communicating artery aneurysms after endovascular coiling. One hundred seventeen of 124 anterior communicating artery aneurysms had complete imaging and follow-up for clinical outcome analysis, stability of aneurysm coil packing, and follow-up imaging between 5 and 7 months after treatment. Clinical outcomes were assessed by the mRS at 6 months. RESULTS: Anterior cerebral artery trunk-dominance was seen in 91 of 124 (73%) anterior communicating artery aneurysms and codominance in 33 of 124 (27%) anterior communicating artery aneurysms. There was no significant difference (P > .5) in treatment success at 5-7 months for anterior communicating artery aneurysms between the anterior cerebral artery trunk-dominant (49 of 86, 57%) and anterior cerebral artery trunk-codominant (19 of 31) groups. Angiographic follow-up demonstrates a statistically significant increase in neck remnants and progressive aneurysm sac filling with the A1 dominant configuration (n = 21, 24% at follow-up versus n = 11, 12% at immediate posttreatment, P = .035). There was no statistically significant difference in clinical outcomes between types of anterior cerebral artery trunk configuration (P > .5). CONCLUSIONS: Anterior communicating artery aneurysms with anterior cerebral artery trunk-dominant circle of Willis configurations show less angiographic stability at follow-up than those with anterior cerebral artery trunk-codominance similar to other "termination" type aneurysms. This supports the hypothesis that anterior cerebral artery trunk-dominant flow contributes to aneurysm formation, growth, and instability after coiling treatment.


Assuntos
Círculo Arterial do Cérebro/anormalidades , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Adulto , Variação Anatômica , Angiografia Cerebral , Círculo Arterial do Cérebro/diagnóstico por imagem , Embolização Terapêutica/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
11.
AJNR Am J Neuroradiol ; 35(5): 935-42, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24481333

RESUMO

BACKGROUND AND PURPOSE: The ability of polymer-modified coils to promote stable aneurysm occlusion after endovascular treatment is not well-documented. Angiographic aneurysm recurrence is widely used as a surrogate for treatment failure, but studies documenting the correlation of angiographic recurrence with clinical failure are limited. This trial compares the effectiveness of Matrix(2) polyglycolic/polylactic acid biopolymer-modified coils with bare metal coils and correlates the angiographic findings with clinical failure (ie, target aneurysm recurrence), a composite end point that includes any incident of posttreatment aneurysm rupture, retreatment, or unexplained death. MATERIALS AND METHODS: This was a multicenter randomized noninferiority trial with blinded end point adjudication. We enrolled 626 patients, divided between Matrix(2) and bare metal coil groups. The primary outcome was target aneurysm recurrence at 12 ± 3 months. RESULTS: At 455 days, at least 1 target aneurysm recurrence event had occurred in 14.6% of patients treated with bare metal coils and 13.3% of Matrix(2) (P = .76, log-rank test) patients; 92.8% of target aneurysm recurrence events were re-interventions for aneurysms that had not bled after treatment, and 5.8% of target aneurysm recurrence events resulted from hemorrhage or rehemorrhage, with or without retreatment. Symptomatic re-intervention occurred in only 4 (0.6%) patients. At 455 days, 95.8% of patients with unruptured aneurysms and 90.4% of those with ruptured aneurysms were independent (mRS ≤ 2). Target aneurysm recurrence was associated with incomplete initial angiographic aneurysm obliteration, presentation with rupture, and a larger aneurysmal dome and neck size. CONCLUSIONS: Tested Matrix(2) coils were not inferior to bare metal coils. Endovascular coiling of intracranial aneurysms was safe, and the rate of technical success was high. Target aneurysm recurrence is a promising clinical outcome measure that correlates well with established angiographic measurements.


Assuntos
Materiais Revestidos Biocompatíveis/química , Embolização Terapêutica/instrumentação , Matriz Extracelular/química , Aneurisma Intracraniano/cirurgia , Platina/química , Stents/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Embolização Terapêutica/mortalidade , Análise de Falha de Equipamento , Feminino , Humanos , Incidência , Internacionalidade , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/mortalidade , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Radiografia , Recidiva , Fatores de Risco , Método Simples-Cego , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
12.
AJNR Am J Neuroradiol ; 35(1): 124-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23868159

RESUMO

BACKGROUND AND PURPOSE: Independent evaluation of angiographic images is becoming widely applied in the assessment of treatment outcomes of cerebral aneurysms. In the current study, we assessed the agreement between an independent core laboratory and the operators regarding angiographic appearance in a recent randomized, controlled trial. MATERIALS AND METHODS: Data were derived from the Cerecyte Coil Trial. Angiographic images of each coiled aneurysm, taken immediately after embolization and at 5- to 7-month follow-up, were evaluated by the operator at the treating center and by an independent neuroradiologist at the core laboratory. For the purpose of this study, images were interpreted on a 3-point scale to provide uniformity for analysis; grade 1: complete occlusion, grade 2: neck remnant; and grade 3: sac filling. "Unfavorable angiographic appearance" was defined as grade 3 at follow-up or interval worsening of grade between the 2 time points. RESULTS: The study included 434 aneurysms. Immediately after embolization, grade 3 was reported by operators in 39 (9%) compared with 52 (12%) by the core laboratory (P = .159). On follow-up, grade 3 was reported by operators in 44 (10%) compared with 81 (19%) by the core laboratory (P < .0001). Overall, operators noted unfavorable angiographic appearance in 78 (18%) compared with 134 (31%) by the core laboratory (P < .0001). At every time point, agreement between the core laboratory and the operators was slight. CONCLUSIONS: Unfavorable angiographic appearance was noted almost twice as frequently by an independent core laboratory as compared with the operators. Planning of trials and interpretation of published studies should be done with careful attention to the mode of angiographic appearance interpretation.


Assuntos
Angiografia Cerebral/estatística & dados numéricos , Embolização Terapêutica/estatística & dados numéricos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Corpo Clínico Hospitalar/estatística & dados numéricos , Competência Profissional/estatística & dados numéricos , Radiografia Intervencionista/estatística & dados numéricos , Embolização Terapêutica/instrumentação , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
J Food Sci ; 78(10): C1535-C1542, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24102418

RESUMO

Fluid whey or retentate are often bleached to remove residual annatto Cheddar cheese colorant, and this process causes off-flavors in dried whey proteins. This study determined the impact of temperature and bleaching agent on bleaching efficacy and volatile components in fluid whey and fluid whey retentate. Freshly manufactured liquid whey (6.7% solids) or concentrated whey protein (retentate) (12% solids, 80% protein) were bleached using benzoyl peroxide (BP) at 100 mg/kg (w/w) or hydrogen peroxide (HP) at 250 mg/kg (w/w) at 5 °C for 16 h or 50 °CC for 1 h. Unbleached controls were subjected to a similar temperature profile. The experiment was replicated three times. Annatto destruction (bleaching efficacy) among treatments was compared, and volatile compounds were extracted and separated using solid phase microextraction gas chromatography mass spectrometry (SPME GC-MS). Bleaching efficacy of BP was higher than HP (P < 0.05) for fluid whey at both 5 and 50 °C. HP bleaching efficacy was increased in retentate compared to liquid whey (P < 0.05). In whey retentate, there was no difference between bleaching with HP or BP at 50 or 5 °C (P > 0.05). Retentate bleached with HP at either temperature had higher relative abundances of pentanal, hexanal, heptanal, and octanal than BP bleached retentate (P < 0.05). Liquid wheys generally had lower concentrations of selected volatiles compared to retentates. These results suggest that the highest bleaching efficacy (within the parameters evaluated) in liquid whey is achieved using BP at 5 or 50 °C and at 50 °C with HP or BP in whey protein retentate.


Assuntos
Clareadores/química , Proteínas do Leite/química , Compostos Orgânicos Voláteis/análise , Aldeídos/análise , Peróxido de Benzoíla/química , Bixaceae , Carotenoides/análise , Queijo/análise , Cor , Manipulação de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Peróxido de Hidrogênio/química , Extratos Vegetais/análise , Microextração em Fase Sólida , Paladar , Temperatura , Proteínas do Soro do Leite
14.
J Med Microbiol ; 62(Pt 10): 1614-1616, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23788596

RESUMO

We report a case of listeriosis linked to consumption of contaminated ox tongue. A public health investigation identified intermittent contamination at a meat-production process and ox-tongue production was discontinued. Sensitive molecular subtyping methods are improving our ability to track sources of Listeria monocytogenes contamination through the food chain. Detailed investigation of sporadic cases of listeriosis can provide important public health information and its wider use is encouraged.


Assuntos
Contaminação de Alimentos , Doenças Transmitidas por Alimentos/diagnóstico , Listeria monocytogenes/isolamento & purificação , Listeriose/diagnóstico , Idoso , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Listeria monocytogenes/classificação , Listeria monocytogenes/genética , Listeria monocytogenes/imunologia , Masculino , Tipagem Molecular , Sorotipagem
16.
Diabetologia ; 54(11): 2832-44, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21882062

RESUMO

AIMS/HYPOTHESIS: We sought to determine the mRNA transcriptome of all major human pancreatic endocrine and exocrine cell subtypes, including human alpha, beta, duct and acinar cells. In addition, we identified the cell type-specific distribution of transcription factors, signalling ligands and their receptors. METHODS: Islet samples from healthy human donors were enzymatically dispersed to single cells and labelled with cell type-specific surface-reactive antibodies. Live endocrine and exocrine cell subpopulations were isolated by FACS and gene expression analyses were performed using microarray analysis and quantitative RT-PCR. Computational tools were used to evaluate receptor-ligand representation in these populations. RESULTS: Analysis of the transcriptomes of alpha, beta, large duct, small duct and acinar cells revealed previously unrecognised gene expression patterns in these cell types, including transcriptional regulators HOPX and HDAC9 in the human beta cell population. The abundance of some regulatory proteins was different from that reported in mouse tissue. For example, v-maf musculoaponeurotic fibrosarcoma oncogene homologue B (avian) (MAFB) was detected at equal levels in adult human alpha and beta cells, but is absent from adult mouse beta cells. Analysis of ligand-receptor interactions suggested that EPH receptor-ephrin communication between exocrine and endocrine cells contributes to pancreatic function. CONCLUSIONS/INTERPRETATION: This is the first comprehensive analysis of the transcriptomes of human exocrine and endocrine pancreatic cell types-including beta cells-and provides a useful resource for diabetes research. In addition, paracrine signalling pathways within the pancreas are shown. These results will help guide efforts to specify human beta cell fate by embryonic stem cell or induced pluripotent stem cell differentiation or genetic reprogramming.


Assuntos
Pâncreas/citologia , Pâncreas/metabolismo , Transcriptoma , Adulto , Células Cultivadas , Biologia Computacional/métodos , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Células Secretoras de Glucagon/citologia , Células Secretoras de Glucagon/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Ligantes , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Pâncreas Exócrino/citologia , Pâncreas Exócrino/metabolismo , Ductos Pancreáticos/citologia , Ductos Pancreáticos/metabolismo , Comunicação Parácrina , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
17.
AJNR Am J Neuroradiol ; 32(2): 359-64, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21051518

RESUMO

BACKGROUND AND PURPOSE: CTA-SI have been previously reported to correlate with CBV. We hypothesized that CTA-SI performed by modern multisection CT scanners are CBF-, not CBV-weighted. MATERIALS AND METHODS: Sixty-four consecutive patients with anterior circulation stroke symptoms were selected from a stroke data base between June 2007 and January 2009. Two independent blinded readers calculated defect volumes of CTA-SI and PCCT, CBF, and CBV images. Spearman correlation of lesion volumes was performed. Linear regression and residual analysis demonstrated factors associated with outliers for CTA or PCCT for CBF and CBV volumes. RESULTS: We found a strong positive correlation between CTA with CBF (r = 0.89, P < .0001) and between PCCT and CBV (r = 0.79, P < .0001). CTA to CBV (r = 0.5, P < .0001) and PCCT to CBF (r = 0.52, P < .0001) correlations were weaker. Positive CTA outliers had lower ASPECTS (P = .01), larger baseline CTA (149 ± 46 cm(3) versus 83 ± 32 cm(3); P = .002, respectively), and final infarct (190 ± 100 cm(3) versus 80 ± 50 cm(3); P = .09, respectively) volumes than nonoutliers. No baseline features were significantly related to PCCT outliers. There was no difference in the vessel occlusion sites for positive or negative outliers for CTA or PCCT (P = .55 and P = 1.00, respectively). CONCLUSIONS: Our results indicate that CTA-SI are CBF- rather than CBV-weighted.


Assuntos
Volume Sanguíneo/fisiologia , Angiografia Cerebral/métodos , Circulação Cerebrovascular/fisiologia , Infarto da Artéria Cerebral Anterior/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Bases de Dados Factuais , Humanos , Infarto da Artéria Cerebral Anterior/fisiopatologia , Modelos Lineares
18.
AJNR Am J Neuroradiol ; 31(7): 1186-91, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20360345

RESUMO

BACKGROUND AND PURPOSE: There is a high incidence of intracranial aneurysms of the AcomA suggesting the possibility of an anatomic risk factor. There also exists an association of termination-type aneurysms with anatomic variations of 1 anterior cerebral artery trunk (A1) as the exclusive or dominant supply to both pericallosal arteries (A2). This yields the hypotheses of aneurysm formation from straight jets of A1 blood. MATERIALS AND METHODS: The anatomy and contrast filling of A1 and A2 segments and AcomAs were studied for a subset of cases entered into the Cerecyte Coil Trial for patients with AcomA (n = 105) and other aneurysms (n = 123) that were selected from imaging available at the Cerecyte Core Trial angiographic Core Lab. These cases were analyzed for A1 vessel dominance by measurement of the vessel diameter and dilution of angiographic contrast agent in A2s due to the differential flow source on selective angiography. A control group without aneurysms was assessed anatomically, using a large sequential CTA series (n = 159), acquired during acute stroke assessment. RESULTS: A1 dominance configuration is strongly associated with the presence of AcomA aneurysms for patients with intracranial aneurysms (odds ratio, 17.8). This association is also present compared with the incidence of A1 dominance in the large sequential control series of patients without aneurysms undergoing CTA for other reasons (odds ratio, 7.5). Outflow dilution of selective angiographic images augments anatomic information. CONCLUSIONS: A flow-based assessment of contrast flowing from the A1 to the A2 segments after injection pressure is superior to an A1 diameter based categorization when A1 vessel diameters are not strikingly different. The anatomic variant of asymmetric A1 configurations likely facilitates the development of AcomA aneurysms by flow stresses, providing further evidence to support the role of biophysical factors in intracranial aneurysm development.


Assuntos
Artéria Cerebral Anterior/diagnóstico por imagem , Angiografia Cerebral/métodos , Circulação Cerebrovascular/fisiologia , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artéria Cerebral Anterior/anormalidades , Feminino , Humanos , Incidência , Técnicas de Diluição do Indicador , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Fatores de Risco
19.
Clin Microbiol Infect ; 16(3): 232-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19416293

RESUMO

Several recent studies have highlighted the emergence of a globally disseminated clone of uropathogenic and invasive Escherichia coli isolates of serotype O25:H4 and sequence type 131. The ability to characterize rapidly E. coli isolates of this lineage would facilitate enhanced surveillance for this pathogen. We have used the semi-automated DiversiLab repetitive PCR-based system to analyse a collection of 35 clinical isolates of uropathogenic E. coli from across the UK, with particular focus on the O25:H4-ST131 lineage. All isolates had been characterized using multilocus sequence typing (MLST), and 14 had previously been typed using pulsed-field gel electrophoresis (PFGE). The DiversiLab system allowed discrimination of O25:H4-ST131 isolates from those of other E. coli lineages. It was slightly more discriminatory than MLST, but was less discriminatory than PFGE. With an analysis time of <4 h between receipt of a cultured organism and provision of a typing result, the system offers information on a real-time basis, a major advantage over current practice. We suggest that introduction of the DiversiLab system would be useful for rapid exclusion of E. coli isolates during outbreak investigations, and that the approach could be employed for surveillance for pathogenic or antibiotic-resistant clones of this organism.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , DNA Bacteriano/genética , Infecções por Escherichia coli/diagnóstico , Reação em Cadeia da Polimerase/métodos , Sequências Repetitivas de Ácido Nucleico , Escherichia coli Uropatogênica/isolamento & purificação , Automação , Impressões Digitais de DNA , Eletroforese em Gel de Campo Pulsado , Humanos , Sensibilidade e Especificidade , Análise de Sequência de DNA , Reino Unido , Escherichia coli Uropatogênica/genética
20.
Anaesthesia ; 64(10): 1137-40, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19735408

RESUMO

SUMMARY: The authors present three cases where catheters placed in the oblique sub-costal transversus abdominis plane provided prolonged analgesia after upper abdominal surgery. Patient 1 was admitted with severe sepsis following major hepatobiliary surgery. Bilateral catheters facilitated weaning from mechanical ventilation and provided adequate analgesia for 4 days. Patient 2 underwent emergency laparotomy for intestinal obstruction having refused consent for epidural analgesia. The transversus abdominis plane catheters provided a significant opioid sparing effect. A unilateral catheter offered rescue analgesia in patient 3 when the epidural catheter was displaced. We put forward a case for oblique sub-costal transversus abdominis plane catheters as an alternative to epidural analgesia after upper abdominal surgery.


Assuntos
Abdome/cirurgia , Bloqueio Nervoso/métodos , Dor Pós-Operatória/terapia , Parede Abdominal , Idoso , Idoso de 80 Anos ou mais , Analgesia Epidural , Anestésicos Locais/administração & dosagem , Contraindicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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