Microfluidic models are proving to be powerful systems to study fundamental processes in porous media, due to their ability to replicate topologically complex environments while allowing detailed, quantitative observations at the pore scale. Yet, while porous media such as living tissues, geological substrates, or industrial systems typically display a porosity that spans multiple scales, most microfluidic models to date are limited to a single porosity or a small range of pore sizes. Here, a novel microfluidic system with multiscale porosity is presented.
View Article and Find Full Text PDFThe Poisson limit is a major problem for the isolation of single cells in different single-cell technologies and applications. In droplet-based single-cell assays, a scheme that is increasingly popular, the intrinsic randomness during single-cell encapsulation in droplets requires most of the created droplets to be empty, which has a profound impact on the efficiency and throughput of such techniques, and on the predictability of the combinatory droplet assays. Here we present a simple passive microfluidic system overcoming this limitation with unprecedented efficacy, allowing the generation of single-cell droplets for a wide range of operating conditions, with extremely high throughput (more than 22 000 single-cell loaded droplets per minute) and with an extremely low fault ratio (doublets or empty droplets), applicable to any cells and deformable particles.
View Article and Find Full Text PDFWe present a novel stochastic model for quantifying gross solids (GS) physical disintegration under varying turbulent flow conditions and used a unique experimental setup for model calibration and validation. The stochastic deterioration model predicts faeces size evolution over time. It conceptually entails the two main processes of solid fragmentation, namely breakage and erosion.
View Article and Find Full Text PDFBackground: This study aimed to investigate the mutation spectrum of the QDPR gene, to determine the effect of mutations on dihydropteridine reductase (DHPR) structure/function, to discuss the potential genotypephenotype correlation, and to evaluate the clinical outcome of Chinese patients after treatment.
Methods: Nine DHPR-deficient patients were enrolled in this study and seven of them underwent neonatal screening. QDPR gene mutations were analyzed and confirmed by routine methods.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
June 2011
Objective: To carry out prenatal diagnosis for a glycogen storage disease type II (GSD II ) affected family.
Methods: The acid-α -glucosidase (GAA) activity was measured in whole leukocytes and cultured amniocytes with 4-methylumbelliferyl-α -D-glucopyranoside as substrate and with acarbose as inhibitor. The coding regions of GAA gene were amplified by polymerase chain reaction and analyzed by direct DNA sequencing.
Zhonghua Yu Fang Yi Xue Za Zhi
February 2009
Objective: To investigate the development of differential diagnosis of tetrahydrobiopterin (BH4) deficiency among patients with hyperphenylalaninemia (HPA) in provinces or cities of China and to investigate the incidence of BH4 deficiency.
Methods: Of the thirteen hundreds and ninety-two patients with HPA received, the differential diagnosis for BH4 deficiency during 1993 - 2007 were enrolled in this study. Of which, 591 patients came from outpatient and 801 patients' samples from other provinces or cities were sent to author's laboratory to investigate the case number of differential diagnosis for BH4 deficiency in provinces or cities of China according to the data from both outpatient case histories and laboratory as to investigating the development of differential diagnosis in the whole country.
Objective: The 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency is the most common type of tetrahydrobiopterin (BH4) deficiency. The reported patients with BH4 deficiency are all PTPS deficient found in the mainland of China previously. The activity of dihydropteridine reductase in BH4 metabolism has been determined for 902 patients with hyperphenylalaninemia in the authors' laboratory since 2003.
View Article and Find Full Text PDFObjective: To investigate the incidence of hyperphenylalaninemia (HPA) caused by different etiologic factors in China and the relationship between the phenylalanine and mental development of patients with HPAs who were diagnosed by neonatal screening and early treated.
Methods: Two hundred and twenty-three patients with HPA detected by neonatal screening programs were refered to us at the age of (41 +/- 27) days after birth. The differential diagnosis was performed by BH(4) (20 mg/kg) loading test, urinary pterin analysis and dihydropteridine reductase (DHPR) activity determination respectively.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
April 2007
Objective: To study the incidence of various enzyme deficiency in tetrahydrobiopterin (BH4) metabolism and the related gene mutation among the patients with motor disturbance and mental retardation.
Methods: One hundred patients with unknown motor disturbance and mental retardation were referred to this study. All patients were performed by phenylalanine (Phe) and BH4 loading test, urinary pterin analysis and dihydropteridine reductase (DHPR) activity.
Zhonghua Liu Xing Bing Xue Za Zhi
June 2002
Objective: To describe trends of changes in blood lead levels in children aged 1 - 6 years during the time period before and after introducing lead free gasoline in Shanghai 1997 and 1999.
Methods: Blood lead levels of 1 969 children aged 1 - 6 years were determined by a sampling survey in five districts of Shanghai in August and September, 1997. Blood lead levels of the same population were re-determined by the same method from April to June in 1998 and from August to September in 1999.
Zhonghua Yu Fang Yi Xue Za Zhi
January 2002
Objective: To investigate the incidence of congenital adrenal hyperplasia (CAH) in Shanghai areas by a neonatal screening program.
Methods: Heel prick blood samples were collected from 50 600 newborns in 50 maternal and child health care hospitals and maternity hospitals 72 hours after their birth and adsorbed onto standard filter paper for determining 17-hydroxyprogesterone (17-OHP) by enzyme linked-immunosorbent assay (ELISA).
Results: Level of 17-OHP was significantly increased in eight cases of the 50 600 newborns, three cases of whom with established CAH with hyponatremia, hyperkalemia and hypertestosteronemia duo to 21-hydroxylase deficiency, and other five cases with high level 17-OHP due to preterm delivery.