1.Determination of polyblend miscibility by dilute-solution viscometry
Wensheng SONG ; Xuejuan LI ; Qingcun FU ; Hongyong YAN
Chinese Journal of Tissue Engineering Research 2008;12(6):1161-1164
BACKGROUND: Polyblends composed of thermoplastic polyurethane elastomer (TPU) and bisphenol A type of polysulfone (PSF) or polymethyl methacrylate (PMMA) can improve the properties of TPU, bisphenol A type of polysulfone or PMMA and can widen the scope of application. The property of polyblends bad or good depends on the miscibility of polyblends. The dilute-solution viscometry (DSV) is a simple and rapid way for determining the miscibility for polyblends. The study on the determination of miscibility for TPU/PSF and TPU/PMMA polyblends by the DSV has not been reported up to now. OBJECTIVE: To differentiate the miscibility of TPU/PSF polyblend and that of TPU/PMMA polyblend, and at the same time to verify the consistency of μ and α criteria in the determination of polyblend miscibility by DSV.DESIGN: Observation and contrast analysis based on the two polyblend systems.SETTING: Chemical Engineering and Pharmaceutics College, Henan University of Science and Technology.MATERIALS: TPU sample was purchased from Luoyang Jiming Chemical Industry Limited Company, China. PSF sample was purchased from the First Plastic Factory of Dalian, China. PMMA sample was synthesized by our laboratory. N, N-dimethylformamide was provided by Beijing Chemical Plant.METHODS:This study was performed at the Key Laboratory of Polymer Science and Nano-technology, Henan University of Science and Technology in May 2006. The different molar ratio of TPU / PSF and TPU / PMMA polyblends were prepared in N, N-dimethylformamide. An ubbelohde dilution viscometer (whose inner diameter was between 0.5 mm and 0.6 mm) was employed for measuring the relative viscosities of the polymer solutions in DMF at (25±0.01) ℃. The second stop-clock was used to record efflux time. From the efflux time, the relative viscosities could be obtained. Then the specific viscosities could be given by the relative viscosities value. From a series of relative viscosities, the specific viscosities and other data of two polyblends, μ values and α values of two polyblends were obtained.MAIN OUTCOME MEASURES: The efflux time of two polyblend solutions in an ubbelohde viscometer.RESULTS: The μ and α values of TPU/PSF polyblend were all above zero, which showed that TPU/PSF polyblend was miscible. But the μ and α values of TPU/PMMA polyblend were all below zero, which showed that TPU/PMMA polyblend was immiscible. CONCLUSION:The μ criterion is consistent with the α criterion in judging for polyblend miscibility. DSV method is simple, and it can be used in the determination of polyblend miscibility.
2.Phenotypic and genetic analysis of a child featuring multiple malformations due to copy number variation on chromosome 5.
Huiqin XUE ; Xiayu SUN ; Hongyong LU ; Yan ZHOU ; Yuezhen GUO ; Lei ZHU
Chinese Journal of Medical Genetics 2014;31(1):56-59
OBJECTIVETo determine the origin of chromosomal aberration for a child featuring multiple malformation, and to correlate the genotype with phenotype.
METHODSRoutine G-banding was performed to analyze the karyotype of the patient and her parents, and array comparative genomic hybridization (array CGH) was used for fine mapping of the aberrant region.
RESULTSThe karyotype of the child was ascertained as 46,XY. Array CGH has mapped a 14.21 Mb deletion to 5p15.2p15.33, and a very small 3.67 Mb duplication to 5q35.3. The patient has presented features such as mental retardation, heart defect, low-set ears, hypertelorism and down-slanting palpebral fissures.
CONCLUSIONChromosome 5 copy number variation can cause multiple malformation. In contrast to routine karyotype analysis, array CGH can map aberrant region with much higher resolution and accuracy.
Abnormalities, Multiple ; diagnosis ; genetics ; Chromosome Aberrations ; Chromosomes, Human, Pair 5 ; DNA Copy Number Variations ; Genotype ; Humans ; Infant ; Male ; Phenotype
3.Cerebral venous sinus thrombosis caused by pegasparaginase: a clinical analysis of 8 cases
Yinyan YAN ; Hongyong LIU ; Lihua YU ; Danna LIN ; Lulu HUANG ; Xiaorong LAI ; Yajie ZHANG ; Juan ZI ; Li WU ; Xu LIAO ; Lihua YANG
Chinese Journal of Neuromedicine 2022;21(5):462-468
Objective:To investigate the risk factors and prognoses of cerebral venous sinus thrombosis (CVST) caused by pegasparaginase (PEG-Asp).Methods:A total of 252 children with acute lymphoblastic leukemia (ALL) were treated with PEG-Asp chemotherapy in our hospital from December 2016 to July 2021, including 8 children with CVST. The clinical manifestations, laboratory and imaging features, treatments and prognoses of these children with CVST caused by PEG-Asp were analyzed retrospectively.Results:(1) CVST occurred during induction chemotherapy in 4 children, during re-induction chemotherapy in 3 children, and during consolidation stage in one child. CVST occurred in two children who received PEG-ASP chemotherapy once, in one child who received PEG-Asp chemotherapy twice, and 5 children who received PEG-Asp chemotherapy more than twice. The median time between CVST occurrence and last treatment of PEG-Asp was 20.5 d. (2) The clinical manifestations included paroxysmal headache ( n=4), nausea or vomiting ( n=3), convulsions ( n=2) and persistent blurred vision ( n=1). (3) CVST appeared at the sigmoid sinus ( n=6), transverse sinus ( n=4) and superior sagittal sinus ( n=4), of which one child was complicated with hemorrhage in left frontal parietal and right parietal cortex, and one with reversible posterior encephalopathy syndrome; 8 children were not complicated with thrombus in other parts. (4) Some of the children were complicated with abnormal blood coagulation. When CVST occurred, fibrinogen level decreased in 3 children, anti-thrombin III level decreased in 2 children, and D-dimer level increased in 3 children. (5) Six children were treated with low molecular weight heparin (LMWH), of which, 4 were treated with rivasaban and one with warfarin sequentially. The total course of anticoagulation was 56 d. (6) The symptoms of 6 children disappeared after anticoagulation; Magnetic resonance venography (MRV) showed disappeared thrombus in 4 children and reduced thrombus range in 2 children. One child with intracranial hemorrhage did not use PEG-Asp anymore; 7 accepted PEG-Asp further during follow-up chemotherapy, of which one had CVST recurrence and the range of thrombus was reduced after anticoagulant therapy. Conclusions:When children with ALL develop unexplained neurological symptoms during PEG-Asp chemotherapy, CVST should be highly vigilant. Enhanced MRI and MRV should be performed for early diagnosis. Some children are complicated with abnormal blood coagulation, and LMWH, warfarin and rivasaban are effective. The prognosis is good and there are no sequelae. Most children accepted PEG-Asp again will not have CVST again.