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1.
Membranes (Basel) ; 10(11)2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33207567

RESUMO

An alkali treatment under various operating conditions is conducted on a commercial anion-exchange membrane containing poly(vinyl chloride) (PVC) as a backing and binder to study the effect of the treatment on the mechanical properties by both Müllen burst and tensile tests. Contrary to our expectations, the Müllen burst pressure and tensile strain at break improved significantly after the alkali treatment in comparison to the pristine membrane and then decreased as the treatment period progressed. A good correlation is observed between the area below the stress-strain curve and burst pressure. To understand the obtained results, the PVC degradates are recovered by Soxhlet extraction and characterized via nuclear magnetic resonance and gel permeation chromatography. It is discovered that the PVC main chains degraded in the alkali solution. We propose a composite model to explain the burst pressure improvement mechanism by the change in the chemical structure of the PVC binder.

2.
Membranes (Basel) ; 10(9)2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32932857

RESUMO

Systematic alkali immersion tests of cation-exchange membranes (CEM) with polyvinyl chloride (PVC) as their backing and binder were conducted to compare that of an Anion-exchange membrane (AEM) with the same PVC materials to investigate the mechanism of dehydrochlorination. In the immersion tests, originally colorless and transparent AEM turned violet, and chemical structure analysis showed that polyene was produced by the dehydrochlorination reaction. However, the CEM did not change in color, chemical structure or membrane properties during the test with less than 1M alkali solutions. According to the Donnan equilibrium theory and the experiments using CEM and AEM, the hydroxide ion concentration in the CEM was much lower than that in the AEM under the same conditions. However, when the alkali immersion test was performed using the CEM under more severe conditions (6 M for 168 h at 40 °C), there was a slight change in the color and chemical structure of the CEM, clearly indicating that not only AEMs, but also CEMs with PVC matrixes were deteriorated by alkali, depending on the conditions.

3.
Rinsho Ketsueki ; 61(5): 455-461, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32507808

RESUMO

An 81-year-old female was referred to our hospital with progressive neutropenia and anemia of unknown etiology. We performed a bone marrow biopsy which was notable for hypercellularity, multinucleated megakaryocytes and hypo-granular neutrophils with 2.6% blasts. A diagnosis of myelodysplastic syndrome with multilineage dysplasia (MDS-MLD) was made. Karyotype analysis revealed a t (9;22)(q34;q11.2) BCR-ABL1 fusion with no additional chromosomal abnormalities. BCR-ABL1 was also detected in transcripts from peripheral blood cells as well as in polynuclear leukocytes via FISH. Within one year, her peripheral blood neutrophil count had declined to 403/µl; further analysis was notable for increasing dysplasia including enlarged platelets and hypo-granular neutrophils. Platelet counts gradually increased over time and reached 100×104/µl. A second bone marrow examination revealed similar cell morphology and the BCR-ABL1 translocation. Her condition deteriorated and blood transfusions were required. Treatment with low doses of the tyrosine kinase inhibitor (TKI), imatinib mesylate (100 mg), was initiated. Thereafter, both the neutropenia and anemia resolved gradually, platelet counts returned to normal levels, and dysplasia eventually disappeared. Detection of the BCR-ABL fusion in mRNA decreased to < 0.0007% (IS%) after 16 months of treatment. Several cases of BCR-ABL1-positive myelodysplastic syndrome treated with TKIs have been reported. Our results suggest that complete hematologic recovery in response to imatinib mesylate suggests a critical role for the BCR-ABL1 fusion in the pathogenesis of this disease.


Assuntos
Anemia , Síndromes Mielodisplásicas , Neutropenia , Idoso de 80 Anos ou mais , Anemia/complicações , Feminino , Proteínas de Fusão bcr-abl , Humanos , Mesilato de Imatinib , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/tratamento farmacológico , Neutropenia/complicações , Inibidores de Proteínas Quinases
4.
Membranes (Basel) ; 8(4)2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30558251

RESUMO

Performance of anion exchange membranes (AEMs), including polyvinyl chloride (PVC) as backing and binder, decreases during a repetitive cleaning-in-place (CIP) treatment using alkali. In this study, we have systematically performed two optical analyses, relative total visible (VIS) reflectance and handheld X-ray fluorescence (XRF), for alkali-attacked commercially available AEM (Neosepta® AMX, Tokyo, Japan) with different NaOH immersion conditions (0⁻1.0 M NaOH at 40⁻80 °C for 0⁻168 h). The VIS reflectance and XRF data were then compared with the electrical and mechanical performances (i.e., membrane resistance, proton rejection, amount of fixed-charge sites, and Young's modulus) of the alkali-attacked AMXs. The result indicated that there are clear linear relationships between their performances and both VIS reflectance and XRF data especially at 40 °C, indicating both optical analyses have a good possibility as a quick diagnosis-in-place (DIP) to predict the resulting performance of the alkali-attacked AMXs. In addition, we also found a clear linear relationship between VIS reflectance and XRF data, so that polyene formations through dehydrochlorination of PVC during alkali attack is one of dominant mechanisms for the performance reduction of the alkali-attacked AMX at 40 °C. These results are promising to be useful for the analysis of ion exchange membranes (IEMs) used in real commercial processes on-site in future.

5.
Antimicrob Agents Chemother ; 59(9): 5107-13, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26100708

RESUMO

The efficacy of cefmetazole and flomoxef (CF) for the treatment of patients with extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-EC) bacteremia (ESBL-CF group) was compared with that of carbapenem treatment for ESBL-EC patients (ESBL-carbapenem group) and with that of CF treatment in patients with non-ESBL-EC bacteremia (non-ESBL-CF group). Adult patients treated for E. coli bacteremia in four hospitals were retrospectively evaluated. The 30-day mortality rates in patients belonging to the ESBL-CF, ESBL-carbapenem, and non-ESBL-CF groups were compared as 2 (empirical and definitive therapy) cohorts. The adjusted hazard ratios (aHRs) for mortality were calculated using Cox regression models with weighting according to the inverse probability of propensity scores for receiving CF or carbapenem treatment. The empirical-therapy cohort included 104 patients (ESBL-CF, 26; ESBL-carbapenem, 45; non-ESBL-CF, 33), and the definitive-therapy cohort included 133 patients (ESBL-CF, 59; ESBL-carbapenem, 54; non-ESBL-CF, 20). The crude 30-day mortality rates for patients in the ESBL-CF, ESBL-carbapenem, and non-ESBL-CF groups were, respectively, 7.7%, 8.9%, and 3.0% in the empirical-therapy cohort and 5.1%, 9.3%, and 5.0% in the definitve-therapy cohort. In patients without hematological malignancy and neutropenia, CF treatment for ESBL-EC patients was not associated with mortality compared with carbapenem treatment (empirical-therapy cohort: aHR, 0.87; 95% confidence interval [CI], 0.11 to 6.52; definitive therapy cohort: aHR, 1.04; CI, 0.24 to 4.49). CF therapy may represent an effective alternative to carbapenem treatment for patients with ESBL-EC bacteremia for empirical and definitive therapy in adult patients who do not have hematological malignancy and neutropenia.


Assuntos
Bacteriemia/microbiologia , Cefmetazol/farmacologia , Cefalosporinas/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , beta-Lactamases/metabolismo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Pediatr Int ; 56(1): 100-2, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24548193

RESUMO

This study is the first to report a familial case involving differing clinical courses of aplastic crisis triggered by parvovirus B19 in two patients with HS, although similar eosin-5-maleimide-binding test and sodium dodecylsulfate-polyacrylamide gel electrophoresis results had been obtained for both. One patient had short-term mild symptoms, whereas the other patient developed severe anemia that required blood transfusion, experienced fever for 13 days, and did not have any rash. The severity of aplastic crisis is reported to be correlated with the severity of the underlying hemolytic anemia; the present findings show that the severity of infection should also be considered as an important predictive factor of the severity of aplastic crisis.


Assuntos
Anemia Aplástica/etiologia , Anticorpos Anti-Idiotípicos/análise , Imunoglobulina M/imunologia , Esferocitose Hereditária/complicações , Adulto , Anemia Aplástica/diagnóstico , Criança , Feminino , Humanos , Masculino , Índice de Gravidade de Doença , Esferocitose Hereditária/diagnóstico
7.
Diagn Microbiol Infect Dis ; 73(2): 149-52, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22503164

RESUMO

Ocular candidiasis is a major complication of Candida bloodstream infection (BSI). This study was performed to reveal the clinical characteristics of ocular candidiasis. Of the 220 patients with Candida BSI, 204 cases received ophthalmology consultations between January 2005 and December 2011 at 2 teaching hospitals. Fifty-four (26.5%) cases had findings consistent with the diagnosis of ocular candidiasis. Of these 54 cases, 43 (79.6%) were diagnosed within 7 days after a positive blood culture. Among ocular candidiasis cases, more cases were due to Candida albicans (P =0.034 odds ratio [OR]; 3.68 95% confidence interval [CI] 1.11-12.2) and had higher ß-d-glucan values (P = 0.001 OR; 9.99 95% CI 2.60-21.3). We need to consider fundoscopic examination to be performed within the first 7 days of therapy, especially for those patients who have C. albicans BSIs and higher ß-d-glucan values. Additionally, follow-up fundoscopic examination should be considered before stopping therapy for high-risk patients.


Assuntos
Candidemia/epidemiologia , Candidemia/patologia , Candidíase/epidemiologia , Candidíase/patologia , Infecções Oculares Fúngicas/epidemiologia , Infecções Oculares Fúngicas/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Diagnóstico Oftalmológico , Infecções Oculares Fúngicas/diagnóstico , Infecções Oculares Fúngicas/patologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Fatores de Risco , beta-Glucanas/metabolismo
8.
Rinsho Ketsueki ; 43(3): 170-5, 2002 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-11979748

RESUMO

A multi-center series of 117 patients with malignant lymphoma were analyzed to evaluate the clinical significance of soluble interleukin-2 receptor alpha chain (sIL-2R alpha). The initial levels of sIL-2R alpha ranged from 277 U/ml to 22,800 U/ml with a mean level of 3,451 +/- 4,268 U/ml and a median level of 1,600 U/ml. The sIL-2R alpha levels of the diffuse lymphoma/intermediate-grade subtypes defined by the LSG classification/Working Formulation were higher than those of the follicular lymphoma/low-grade subtypes. There was a tendency for B-cell lymphomas to show higher sIL-2R alpha levels than T-cell lymphomas. The sIL-2R alpha level was correlated with the Ann Arbor clinical stage (I, II versus III, IV), presence or absence of B symptoms, and performance status (0, 1 versus 2, 3, 4) of the patients. The sIL-2R alpha levels were in good accordance with the four risk groups defined by the International Prognostic Indices. Of 21 patients whose tumor burden was serially measured, the coefficients of correlation between sIL-2R alpha and tumor mass were > 0.6 in 18 cases. Sixty-two patients achieved complete remission (CR) during the study; the initial and minimum sIL-2R alpha levels were lower than those of the non-CR patients. This study confirmed that sIL-2R alpha is a convenient and useful marker in the management of malignant lymphoma.


Assuntos
Linfoma não Hodgkin/tratamento farmacológico , Receptores de Interleucina-2/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Receptores de Interleucina-2/sangue , Fatores de Risco
9.
Blood ; 99(8): 2748-51, 2002 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11929762

RESUMO

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hematopoietic stem cell disorder characterized by clonal blood cells that are deficient in glycosylphosphatidylinositol-anchored proteins because of somatic mutations of the PIG-A gene. Many patients with PNH have more than one PNH clone, but it is unclear whether a single PNH clone remains dominant or minor clones eventually become dominant. Furthermore, it is unknown how many hematopoietic stem cells (HSCs) sustain hematopoiesis and how long a single HSC can support hematopoiesis in humans. To understand dynamics of HSCs, we reanalyzed the PIG-A gene mutations in 9 patients 6 to 10 years after the previous analyses. The proportion of affected peripheral blood polymorphonuclear cells (PMNs) in each patient was highly variable; it increased in 2 (from 50% and 65% to 98% and 97%, respectively), was stable in 4 (changed less than 20%), and diminished in 3 (94%, 99%, and 98% to 33%, 57%, and 43%, respectively) patients. The complexity of these results reflects the high variability of the clinical course of PNH. In all patients, the previously predominant clone was still present and dominant. Therefore, one stem cell clone can sustain hematopoiesis for 6 to 10 years in patients with PNH. Two patients whose affected PMNs decreased because of a decline of the predominant PNH clone and who have been followed up for 24 and 31 years now have an aplastic condition, suggesting that aplasia is a terminal feature of PNH.


Assuntos
Hematopoese , Células-Tronco Hematopoéticas/patologia , Hemoglobinúria Paroxística/patologia , Hemoglobinúria Paroxística/fisiopatologia , Adulto , Idoso , Células Clonais/química , Células Clonais/patologia , Análise Mutacional de DNA , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Masculino , Proteínas de Membrana/análise , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Mutação , Neutrófilos/química , Neutrófilos/patologia
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