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PURPOSE: Anti-granulocyte-macrophage colony-stimulating factor autoantibodies (anti-GM-CSF Abs) are implicated in the pathogenesis of Cryptococcus gattii (C. gattii) infection and pulmonary alveolar proteinosis (PAP). Their presence has also been noted in nocardiosis cases, particularly those with disseminated disease. This study delineates a case series characterizing clinical features and specificity of anti-GM-CSF Abs in nocardiosis patients. METHODS: In this study, eight patients were recruited to determine the presence or absence of anti-GM-CSF Abs. In addition to the detailed description of the clinical course, we thoroughly investigated the autoantibodies regarding the characteristics, isotypes, subclasses, titers, and neutralizing capacities by utilizing the plasma samples from patients. RESULTS: Of eight patients, five tested positive for anti-GM-CSF Abs, all with central nervous system (CNS) involvement; patients negative for these antibodies did not develop CNS nocardiosis. Distinct from previously documented cases, none of our patients with anti-GM-CSF Abs exhibited PAP symptoms. The titer and neutralizing activity of anti-GM-CSF Abs in our cohort did not significantly deviate from those found in C. gattii cryptococcosis and PAP patients. Uniquely, one individual (Patient 3) showed a minimal titer and neutralizing action of anti-GM-CSF Abs, with no relation to disease severity. Moreover, IgM autoantibodies were notably present in all CNS nocardiosis cases investigated. CONCLUSION: The presence of anti-GM-CSF Abs suggests an intrinsic immunodeficiency predisposing individuals toward CNS nocardiosis. The presence of anti-GM-CSF Abs helps to elucidate vulnerability to CNS nocardiosis, even with low titer of autoantibodies. Consequently, systematic screening for anti-GM-CSF Abs should be considered a crucial diagnostic step for nocardiosis patients.
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Autoanticorpos , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Nocardiose , Humanos , Autoanticorpos/imunologia , Autoanticorpos/sangue , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Nocardiose/imunologia , Nocardiose/diagnóstico , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Adulto , Proteinose Alveolar Pulmonar/imunologia , Proteinose Alveolar Pulmonar/diagnóstico , Cryptococcus gattii/imunologiaRESUMO
PURPOSE: Heterozygous STAT1 Gain-of-Function (GOF) mutations are the most common cause of chronic mucocutaneous candidiasis (CMC) among Inborn Errors of Immunity. Clinically, these mutations manifest as a broad spectrum of immune dysregulation, including autoimmune diseases, vascular disorders, and malignancies. The pathogenic mechanisms of immune dysregulation and its impact on immune cells are not yet fully understood. In treatment, JAK inhibitors have shown therapeutic effectiveness in some patients. METHODS: We analyzed clinical presentations, cellular phenotypes, and functional impacts in five Taiwanese patients with STAT1 GOF. RESULTS: We identified two novel GOF mutations in 5 patients from 2 Taiwanese families, presenting with symptoms of CMC, late-onset rosacea, and autoimmunity. The enhanced phosphorylation and delayed dephosphorylation were displayed by the patients' cells. There are alterations in both innate and adaptive immune cells, including expansion of CD38+HLADR +CD8+ T cells, a skewed activated Tfh cells toward Th1, reduction of memory, marginal zone and anergic B cells, all main functional dendritic cell lineages, and a reduction in classical monocyte. Baricitinib showed therapeutic effectiveness without side effects. CONCLUSION: Our study provides the first comprehensive clinical and molecular characteristics in STAT1 GOF patient in Taiwan and highlights the dysregulated T and B cells subsets which may hinge the autoimmunity in STAT1 GOF patients. It also demonstrated the therapeutic safety and efficacy of baricitinib in pediatric patient. Further research is needed to delineate how the aberrant STAT1 signaling lead to the changes in cellular populations as well as to better link to the clinical manifestations of the disease.
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Candidíase Mucocutânea Crônica , Mutação com Ganho de Função , Imunofenotipagem , Pirazóis , Fator de Transcrição STAT1 , Humanos , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Candidíase Mucocutânea Crônica/genética , Candidíase Mucocutânea Crônica/diagnóstico , Candidíase Mucocutânea Crônica/terapia , Masculino , Feminino , Pirazóis/uso terapêutico , Sulfonamidas/uso terapêutico , Azetidinas/uso terapêutico , Purinas/uso terapêutico , Criança , Adolescente , Taiwan , AdultoRESUMO
Confirmatory tests for diagnosis of primary aldosteronism (PA) play an important role in sparing patients with a false-positive aldosterone-to-renin ratio (ARR) screening test from undergoing invasive subtyping procedures. We recommend that patients with a positive ARR test should undergo at least one confirmatory test to confirm or exclude the diagnosis of PA before directly proceeding to subtype studies, except for patients with significant PA phenotypes, including spontaneous hypokalemia, plasma aldosterone concentration >20 ng/dL plus plasma renin activity below a detectable level. Although a gold standard confirmatory test has not been identified, we recommend that saline infusion test and captopril challenge test, which were widely used in Taiwan. Patients with PA have been reported to have a higher prevalence of concurrent autonomous cortisol secretion (ACS). ACS is a biochemical condition of mild cortisol overproduction from adrenal lesions, but without the typical clinical features of overt Cushing's syndrome. Concurrent ACS may result in incorrect interpretation of adrenal venous sampling (AVS) and may lead to adrenal insufficiency after adrenalectomy. We recommend screening for ACS in patients with PA scheduled for AVS examinations as well as for adrenalectomy. We recommend the 1-mg overnight dexamethasone suppression test as screening method to detect ACS.
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Hiperaldosteronismo , Hipertensão , Humanos , Aldosterona , Hiperaldosteronismo/diagnóstico , Renina , Hidrocortisona , CaptoprilRESUMO
PURPOSE: Anti-granulocyte-macrophage colony-stimulating factor autoantibodies (anti-GM-CSF Abs) are a predisposing factor for pulmonary alveolar proteinosis (PAP) and Cryptococcus gattii cryptococcosis. This study aimed to investigate clinical manifestations in anti-GM-CSF Ab-positive patients with C. gattii cryptococcosis and analyze the properties of anti-GM-CSF Abs derived from these patients and patients with PAP. METHODS: Thirty-nine patients diagnosed with cryptococcosis (caused by C. neoformans or C. gattii) and 6 with PAP were enrolled in the present study. Clinical information was obtained from medical records. Blood samples were collected for analysis of autoantibody properties. We also explored the National Health Insurance Research Database (NHIRD) of Taiwan to investigate the epidemiology of cryptococcosis and PAP. RESULTS: High titers of neutralizing anti-GM-CSF Abs were identified in 15 patients with cryptococcosis (15/39, 38.5%). Most anti-GM-CSF Ab-positive cryptococcosis cases had central nervous system (CNS) involvement (14/15, 93.3%). Eleven out of 14 (78.6%) anti-GM-CSF Ab-positive CNS cryptococcosis patients were confirmed to be infected with C. gattii, and PAP did not occur synchronously or metachronously in a single patient from our cohort. Exploration of an association between HLA and anti-GM-CSF Ab positivity or differential properties of autoantibodies from cryptococcosis patients and PAP yielded no significant results. CONCLUSION: Anti-GM-CSF Abs can cause two diseases, C. gattii cryptococcosis and PAP, which seldom occur in the same subject. Current biological evidence regarding the properties of anti-GM-CSF Abs cannot provide clues regarding decisive mechanisms. Further analysis, including more extensive cohort studies and investigations into detailed properties, is mandatory to better understand the pathogenesis of anti-GM-CSF Abs.
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Criptococose , Proteinose Alveolar Pulmonar , Humanos , Autoanticorpos , Criptococose/diagnóstico , Criptococose/epidemiologia , Proteinose Alveolar Pulmonar/diagnóstico , Proteinose Alveolar Pulmonar/etiologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologiaRESUMO
BACKGROUND: The extent of interstitial fibrosis in the kidney not only correlates with renal function at the time of biopsy but also predicts future renal outcome. However, its assessment by pathologists lacks good agreement. The aim of this study is to construct a machine learning-based model that enables automatic and reliable assessment of interstitial fibrosis in human kidney biopsies. METHODS: Validated cortex, glomerulus and tubule segmentation algorithms were incorporated into a single model to assess the extent of interstitial fibrosis. The model performances were compared with expert renal pathologists and correlated with patients' renal functional data. RESULTS: Compared with human raters, the model had the best agreement [intraclass correlation coefficient (ICC) 0.90] to the reference in 50 test cases. The model also had a low mean bias and the narrowest 95% limits of agreement. The model was robust against colour variation on images obtained at different times, through different scanners, or from outside institutions with excellent ICCs of 0.92-0.97. The model showed significantly better test-retest reliability (ICC 0.98) than humans (ICC 0.76-0.94) and the amount of interstitial fibrosis inferred by the model strongly correlated with 405 patients' serum creatinine (r = 0.65-0.67) and estimated glomerular filtration rate (r = -0.74 to -0.76). CONCLUSIONS: This study demonstrated that a trained machine learning-based model can faithfully simulate the whole process of interstitial fibrosis assessment, which traditionally can only be carried out by renal pathologists. Our data suggested that such a model may provide more reliable results, thus enabling precision medicine.
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Rim , Aprendizado de Máquina , Humanos , Creatinina , Fibrose , Reprodutibilidade dos Testes , Rim/patologia , BiópsiaRESUMO
BACKGROUND: To update information about the internationally accepted standards and clinical recommendations for the detection and diagnosis of primary aldosteronism (PA). METHODS: The Taiwan Society of Aldosteronism (TSA) Task Force reviewed the latest literature and reached a consensus after group meetings. The nine critical issues were recognized to provide updated information and internationally acceptable protocols. RESULTS: When screening for PA by using the plasma aldosterone concentration (PAC) to plasma renin activity (PRA) ratio (ARR), withdrawal or adjustment of antihypertensive medication is not always necessary on the first patient visit. Hypokalemia should be corrected before ARR screening. In spontaneous hypokalemia, plasma renin below detection levels, and PAC higher than 20 ng/dL (550 pmol/L), further confirmatory testing is unnecessary for PA diagnosis. Direct renin concentration (DRC) could be used for PA diagnosis if PRA is unavailable. Although additional confirmatory tests are suggested, the result of a single test is still reliable. For patient safety, discontinuation or adjustment of antihypertensive medications is indicated before adrenal venous sampling (AVS). ACTH could be beneficial for successful adrenal vein cannulation but is not necessary for determining lateralization in AVS. Simultaneous technique is preferred for AVS. Adrenal NP-59 scintigraphy integrated with SPECT/CT could guide PA management. CONCLUSION: With introduction of these new concepts to the clinicians, we expect better identiï¬cation, management and treatment of PA patients.
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Hiperaldosteronismo , Glândulas Suprarrenais , Aldosterona , Humanos , Hiperaldosteronismo/diagnóstico , Hipertensão , Renina , TaiwanRESUMO
TAFRO syndrome is an extremely rare form of idiopathic MCD, characterized by thrombocytopenia, anasarca, fever, reticulin fibrosis on bone marrow biopsy, and organomegaly. Like idiopathic MCD, renal involvement is also a common presentation in patients with TAFRO syndrome. Furthermore, membranoproliferative glomerulonephritis (MPGN)-like injury and thrombotic microangiopathy (TMA) are the most reported histopathologic findings of renal biopsy. Several molecular mechanisms have been previously postulated in order to explain the TAFRO syndrome symptoms, including abnormal production of interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), etc. The role of these cytokines in renal injury, however, is not well understood. The aim of this review article is to summarize the latest knowledge of molecular mechanisms behind the TAFRO syndrome and their potential role in renal damage.
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Hiperplasia do Linfonodo Gigante/complicações , Hiperplasia do Linfonodo Gigante/terapia , Rim/patologia , Microangiopatias Trombóticas/complicações , Microangiopatias Trombóticas/terapia , Animais , Hiperplasia do Linfonodo Gigante/fisiopatologia , Humanos , Microangiopatias Trombóticas/fisiopatologiaRESUMO
BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is often used in critical patients with severe myocardial failure. However, the mortality rate of patients on ECMO is often high. Recent studies have suggested that endothelial activation with subsequent vascular barrier breakdown is a critical pathogenic mechanism of organ damage and is related to the outcome of critical illness. This study aimed to determine whether endothelial biomarkers can be served as prognostic factors for the outcome of patients on ECMO. METHODS: This prospective study enrolled 23 critically ill patients on veno-arterial ECMO in the intensive care units of a tertiary care hospital between March 2014 and February 2015. Serum samples were tested for thrombomodulin, angiopoietin (Ang)-1, Ang-2, and vascular endothelial growth factor (VEGF). Demographic, clinical, and laboratory data were also collected. RESULTS: The overall mortality rate was 56.5%. The combination of Ang-2 at the time of ECMO support (day 0) and VEGF at day 2 had the ability to discriminate mortality (area under receiver operating characteristic curve [AUROC], 0.854; 95% confidence interval: 0.645-0.965). CONCLUSIONS: In this study, we found that the combination of Ang-2 at day 0 and VEGF at day 2 was a modest model for mortality discrimination in this group of patients.
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Endotélio Vascular/metabolismo , Oxigenação por Membrana Extracorpórea/métodos , Choque Cardiogênico/sangue , Choque Cardiogênico/diagnóstico , Fator A de Crescimento do Endotélio Vascular/sangue , Proteínas de Transporte Vesicular/sangue , Adulto , Idoso , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Choque Cardiogênico/mortalidadeRESUMO
BACKGROUND/PURPOSE: A reliable noninvasive prognostic factor of ANCA-associated vasculitis (AAV) is still lacking, but little research has focused on the value of MPO-ANCA titers in patients with active vasculitis. This study explored the prognostic significance of MPO-ANCA titer in active AAV patients. METHODS: Ninety-seven inpatients diagnosed with MPO-ANCA associated vasculitis at Linkou Chang Gung Memorial hospital and Keelung Chang Gung Memorial hospital from January 2005 to December 2016 were enrolled. Serum ANCA titers and basic characteristics of these patients at diagnosis were collected completely Medical records since AAV diagnosis were reviewed to evaluate two years renal and patient outcome. RESULTS: The patients were divided into the two groups according to the median ANCA titers, the more than four times of the normal cut-off value group (high titer group) and the less ANCA titer group (low titer group). The high titer group had significant poor initial renal function (eGFR 16.7 vs 40.7 mL/min/1.73 m2, P = 0.006), and significantly lower two-year renal survival (Log rank P < 0.001). Whereas patient survival (Log rank P = 0.894) was not different The Cox regression models revealed that baseline Birmingham Vasculitis Activity Score, eGFR and a 4-fold increase in ANCA titer were associated with the requirement of permanent dialysis. In the subgroup analysis, the ANCA titer was still an important risk factor for renal outcomes (P = 0.036) in patients with better initial renal function (eGFRâ§15 mL/min). CONCLUSION: This study demonstrated that higher MPO-ANCA titers at diagnosis was associated with poor initial renal function and 2-year renal outcomes.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/sangue , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Anticorpos Anticitoplasma de Neutrófilos/sangue , Falência Renal Crônica/etiologia , Falência Renal Crônica/terapia , Adulto , Idoso , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/enzimologia , Biomarcadores/sangue , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Peroxidase/imunologia , Prognóstico , Modelos de Riscos Proporcionais , Diálise Renal , Estudos Retrospectivos , Índice de Gravidade de Doença , Taxa de SobrevidaRESUMO
Arrays of 14 nm thick L10-FePt nanodots with diameter of 27 nm and center-to-center spacing of 39 nm were produced by block copolymer patterning of an FePt film and their magnetic reversal and thermal stability were characterized. A self-assembled polystyrene-b-polydimethylsiloxane diblock copolymer film was used as a lithographic mask and a pattern transfer process based on ion beam etching and rapid thermal annealing of the sputtered FePt film was developed. The dot arrays exhibited perpendicular magnetic anisotropy with K = 4.8 × 107 erg cm-3 and a saturation magnetization of 960 emu cm-3. First order reversal curves indicate a softer magnetic component attributed to the ion-milled material at the edges of the dots. The switching volume and the thermal stability were obtained from relaxation measurements and DC demagnetization curves. Micromagnetic simulations reproduce the magnetic domain structure obtained for the continuous and patterned FePt thin film.
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Dense arrays of pillars, with diameters of 64 and 25 nm, were made from a perpendicular CoFeB magnetic tunnel junction thin film stack using block copolymer lithography. While the soft layer and hard layer in the 64 nm pillars reverse at different fields, the reversal of the two layers in the 25 nm pillars could not be distinguished, attributed to the strong interlayer magnetostatic coupling. First-order reversal curves were used to identify the steps that occur during switching, and the thermal stability and effective switching volume were determined from scan rate dependent hysteresis measurements.
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Patients with acute liver failure (ALF) and acute-on-chronic liver failure (ACLF) have a high risk of mortality. Few studies have reported prognostic factors for patients receiving plasma exchange (PE) for liver support. We conducted a retrospective analysis using data of 55 patients with severe ACLF (nâ¯=â¯45) and ALF (nâ¯=â¯10) who received standard-volume PE (1-1.5 plasma volume) in the ICU. Hepatitis B virus infection accounts for the majority of ACLF (87%) and ALF (50%) patients. PE significantly improved the levels of total bilirubin, prothrombin time and liver enzymes (P<0.05). Thirteen ACLF patients (29%) and one ALF patient (10%) underwent liver transplantation. Two ALF patients (20%) recovered spontaneously without transplantation. The overall in-hospital survival rates for ACLF and ALF patients were 24% and 30%, and the transplant-free survival rates were 0% and 20%, respectively. For the 14 transplanted patients, the one-year survival rate was 86%. Multivariate analysis showed that pre-PE hemoglobin (Pâ¯=â¯0.008), post-PE hemoglobin (Pâ¯=â¯0.039), and post-PE CLIF-C ACLF scores (Pâ¯=â¯0.061) were independent predictors of survival in ACLF. The post-PE CLIF-C ACLF scores ≥59 were a discriminator predicting the in-hospital mortality (area under the curveâ¯=â¯0.719, Pâ¯=â¯0.030). Cumulative survival rates differed significantly between patients with CLIF-C ACLF scores ≤ 58 and those with CLIF-C ACLF scores ≥ 59 after PE (P< 0.05). The findings suggest that PE is mainly a bridge for liver transplantation and spontaneous recovery is exceptional even in patients treated with PE. A higher improvement in the post-PE CLIF-C ACLF score is associated with a superior in-hospital survival rate.
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Insuficiência Hepática Crônica Agudizada/terapia , Falência Hepática Aguda/terapia , Troca Plasmática/métodos , Insuficiência Hepática Crônica Agudizada/mortalidade , Insuficiência Hepática Crônica Agudizada/patologia , Estudos de Coortes , Feminino , Humanos , Falência Hepática Aguda/mortalidade , Falência Hepática Aguda/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
INTRODUCTION: Autoantibodies to granulocyte-macrophage colony-stimulating factor (GM-CSF) can cause acquired pulmonary alveolar proteinosis (PAP). Cases of acquired PAP susceptible to typical respiratory pathogens and opportunistic infections have been reported. Anti-GM-CSF autoantibodies have been reported in a few patients with cryptococcal meningitis. This study evaluated the presence of neutralizing anti-GM-CSF autoantibodies in patients without known congenital or acquired immunodeficiency with severe pulmonary or extrapulmonary cryptococcal infection but without PAP. METHODS: We took a clinical history and performed an immunologic evaluation and screening of anti-cytokine autoantibodies in patients with cryptococcal meningitis. The impact of autoantibodies to GM-CSF on immune function was assessed by intracellular staining of GM-CSF-induced STAT5 phosphorylation and MIP-1α production in normal peripheral blood mononuclear cells incubated with plasma from patients or normal control subjects. RESULTS: Neutralizing anti-GM-CSF autoantibodies were identified in four patients with disseminated cryptococcosis, none of whom exhibited PAP. Plasma from patients blocked GM-CSF signaling and inhibited STAT5 phosphorylation and production of MIP-1α. One patient died of disseminated cryptococcosis involving the central nervous system, which was associated with defective GM-CSF activity. CONCLUSIONS: Anti-GM-CSF autoantibodies increase susceptibility to cryptococcal infection in adults without PAP. Cryptococcal central nervous system infection associated with anti-GM-CSF autoantibodies could result in neurological sequelae or be life-threatening. Therefore, timely detection of neutralizing anti-GM-CSF autoantibodies and development of an effective therapy are necessary to prevent deterioration of cryptococcal infection in these patients.
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Autoanticorpos/imunologia , Criptococose/etiologia , Criptococose/microbiologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Antifúngicos/uso terapêutico , Autoanticorpos/sangue , Biomarcadores , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Quimiocina CCL3/biossíntese , Criptococose/diagnóstico , Criptococose/tratamento farmacológico , Cryptococcus neoformans/imunologia , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunofenotipagem , Contagem de Leucócitos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/diagnóstico , Infecções Oportunistas/etiologia , Infecções Oportunistas/microbiologia , Fosforilação , Proteinose Alveolar Pulmonar/etiologia , Radiografia Torácica , Fator de Transcrição STAT5/metabolismo , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Aggregation of end-stage renal disease (ESRD) has been observed in families of European origin, as well as those of African origin. However, it is not well documented if this disease aggregates in Asian families. Furthermore, the contribution of genetic factors and shared environmental factors to family aggregation remains unclear. STUDY DESIGN: Population-based cross-sectional cohort study. SETTING & PARTICIPANTS: All 23,422,955 individuals registered in the Taiwan National Health Insurance Research Database in 2013. Among these, 47.45%, 57.45%, 47.29%, and 1.51% had a known parent, child, sibling, or twin, respectively. We identified 87,849 patients who had a diagnosis of ESRD. PREDICTOR: Family history of ESRD. OUTCOMES & MEASUREMENTS: ESRD and heritability defined as the proportion of phenotypic variance attributable to genetic factors. RESULTS: Having an affected first-degree relative with ESRD was associated with an adjusted relative risk of 2.46 (95% CI, 2.32-2.62). Relative risks were 96.38 (95% CI, 48.3-192.34) for twins of patients with ESRD, 2.15 (95% CI, 2.02-2.29) for parents, 2.78 (95% CI, 2.53-3.05) for offspring, 4.96 (95% CI, 4.19-5.88) for siblings, and 1.66 (95% CI, 1.54-1.78) for spouses without genetic similarities. Heritability in this study was 31.1% to 11.4% for shared environmental factors and 57.5% for nonshared environmental factors. LIMITATIONS: This was a registry database study and we did not have detailed information about clinical findings or the definite causes of ESRD. CONCLUSIONS: This whole population-based family study in Asia confirmed, in a Taiwanese population, that a family history of ESRD is a strong risk factor for this disease. Moderate heritability was noted and environmental factors were related to disease. Family history of ESRD is an important piece of clinical information.
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Povo Asiático/genética , Família , Falência Renal Crônica/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/estatística & dados numéricos , Criança , Pré-Escolar , Estudos Transversais , Bases de Dados Factuais , Feminino , Predisposição Genética para Doença , Humanos , Lactente , Recém-Nascido , Falência Renal Crônica/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Risco , Taiwan/epidemiologia , Adulto JovemRESUMO
The self-assembly of block copolymers with large feature sizes is inherently challenging as the large kinetic barrier arising from chain entanglement of high molecular weight (MW) polymers limits the extent over which long-range ordered microdomains can be achieved. Here, we illustrate the evolution of thin film morphology from a diblock copolymer of polystyrene-block-poly(dimethylsiloxane) exhibiting total number average MW of 123 kg mol-1, and demonstrate the formation of layers of well-ordered cylindrical microdomains under appropriate conditions of binary solvent mix ratio, commensurate film thickness, and solvent vapor annealing time. Directed self-assembly of the block copolymer within lithographically patterned trenches occurs with alignment of cylinders parallel to the sidewalls. Fabrication of ordered cobalt nanowire arrays by pattern transfer was also implemented, and their magnetic properties and domain wall behavior were characterized.
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The response of polystyrene-block-poly(dimethylsiloxane) (PS-b-PDMS) thin films to UV exposure during solvent vapor annealing is described, in order to improve their applicability in nanolithography and nanofabrication. Two BCPs were examined, one with the PS block as majority (f PS = 68%, M n = 53 kg mol-1), the other with PDMS block as majority (f PDMS = 67%, M n = 44 kg mol-1). A 5 min UV irradiation was applied during solvent vapor annealing which led to both partial crosslinking of the polymer and a small increase in the temperature of the annealing chamber. This approach was effective for improving the correlation length of the self-assembled microdomain arrays and in limiting subsequent flow of the PDMS in the PDMS-majority BCP to preserve the post-anneal morphology. Ordering and orientation of microdomains were controlled by directed self-assembly of the BCPs in trench substrates. Highly-ordered perpendicular nanochannel arrays were obtained in the PDMS-majority BCP.
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Perpendicular magnetic tunnel junctions (p-MTJs) were patterned into nanopillars using electron-beam lithography to study their scaling and switching behaviour. Magnetoresistance measurements of annealed and unannealed p-MTJ films using scanning probe microscopy showed good agreement with Monte Carlo modeling. p-MTJ pillars demonstrated clear parallel magnetic states, both 'up' or both 'down' following AC-demagnetization. Significant variability in the resistance of p-MTJ pillars was observed and attributed to edge features generated during patterning or local inhomogeneity in the MgO layer.
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BACKGROUND/PURPOSE: Polyomavirus BK (BKV) reactivation causes allograft dysfunction in some kidney transplant recipients. The use of mammalian target of rapamycin (mTOR) inhibitor-based immunotherapy is associated with a lower incidence of polyomavirus-associated nephropathy compared with other immunosuppressants. This retrospective study assessed whether conversion to mTOR inhibitor-based immunotherapy directly reduced urinary BKV load. METHODS: A total of 63 kidney recipients were divided into mTOR inhibitor-conversion (21 patients) and nonconversion (42 patients) groups. Urinary BKV loads were determined before and at least 6 months after the conversion. RESULTS: The results demonstrated that urinary BKV titer was significantly reduced in the conversion group (3.94 ± 0.43 copies (log)/mL to 2.49 ± 0.19 copies (log)/mL) and remained unaltered in the nonconversion group (3.19 ± 0.20 copies (log)/mL to 2.90 ± 0.20 copies (log)/mL). In addition, the percentage of patients with reduced urinary BKV load was significantly higher in the conversion group (76.2% vs. 42.9%). The estimated glomerular filtration rate after 24 months mTOR inhibitor conversion was significantly increased compared with that in the nonconversion group. Conversion to mTOR-inhibitor-based immunotherapy was the only factor associated with an increase in estimated glomerular filtration rate. CONCLUSION: This study reveals an association of conversion to mTOR-inhibitor-based immunotherapy with the reduction of urinary BKV load.
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Vírus BK/efeitos dos fármacos , Imunoterapia , Nefropatias/epidemiologia , Transplante de Rim , Infecções por Polyomavirus/tratamento farmacológico , Serina-Treonina Quinases TOR/antagonistas & inibidores , Adulto , Creatinina/sangue , Everolimo/uso terapêutico , Feminino , Taxa de Filtração Glomerular , Humanos , Imunossupressores/uso terapêutico , Nefropatias/virologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/virologia , Estudos Retrospectivos , Sirolimo/uso terapêutico , Taiwan , Carga Viral/efeitos dos fármacosRESUMO
A universal block copolymer pattern transfer method was demonstrated to produce Co nanostructures consisting of arrays of lines or dots from a polystyrene-block-polydimethylsiloxane (PS-b-PDMS) diblock copolymer. Three processes were used: liftoff, a damascene process, and ion beam etching using a hard mask of tungsten, including a sacrificial poly(methyl methacrylate) layer under the PS-b-PDMS for the etch and liftoff processes. The ion beam etch process produced the most uniform magnetic arrays. A structural and magnetic comparison in terms of uniformity, edge roughness and switching field distribution has been reported.
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Guillain-Barré syndrome (GBS) is an acute immune-mediated demyelinating polyradiculoneuropathy that could lead to disabilities if not properly treated. There are only limited data on the prognostic factors and complications when using double-filtration plasmapheresis in these patients. We reviewed the medical records of 60 GBS patients who underwent double-filtration plasmapheresis as the first-line therapy at a tertiary care teaching hospital. The severity of disease was evaluated at different time points using disability scores. Functional outcome was defined as good (GBS disability score 0 to 2) or poor (GBS disability score 3 to 6) at 28 days after admission. The cohort included 22 women and 38 men with a mean age of 50 ± 18 years. In univariate logistic regression analysis, potential factors associated with poor outcome include an older age (P = 0.101), the absence of preceding respiratory tract infection (P = 0.043), mechanical ventilation (P = 0.016), a lower hematocrit (p = 0.072), a lower serum sodium level (P = 0.153) and a higher disability score on admission (P < 0.001). In multivariate analysis, a higher disability score on admission was associated with a poorer outcome (OR, 5.61; 95% CI, 2.34 to 13.43; P < 0.001), whereas the presence of prodromal upper respiratory tract infection correlated with a better outcome (OR, 0.13; 95% CI, 0.03-0.59; P = 0.009). Among 60 patients, eleven (18.3%) have various complications attributed to plasmapheresis treatment. Six patients (10.0%) developed deep vein thrombosis and two experienced catheter-related infection (3.3%). Hypotension, allergy and hemolysis occurred in one patient each (1.7%). In conclusion, we describe our experiences of using DFPP in the treatment of GBS. The pretreatment severity score was the most significant predictor of treatment outcome, suggesting that early referral and timely treatment are important. Potential complications such as catheter-related infection and deep vein thrombosis should be monitored carefully.