[A Simple Medical Research Microdevice for Analyzing Three-dimensional Migration of Tumor Cells in Vitro].

Objective To develop and verify a medical microdevice for analyzing the three-dimensional(3D)migration of tumor cells in extracellular matrix. Methods The mold of the microdevice was made by precision machining,and then the medical microdevice based on polydimethylsiloxane(PDMS)-glass was obtained by PDMS casting,moulding,and bonding.During the analysis,the suspension of tumor cells and matrigel were mixed and then added into the migration channel of microdevice,and the controllable migration of tumor cells in matrigel was induced by establishing chemokine concentration gradient on both sides of the migration channel.Meanwhile,the migration process of tumor cells was recorded with the live cell dynamic imaging device. Results Breast cancer cell line MCF-7 was taken as an example to verify the feasibility of the microdevice to control and dynamically monitor the 3D migration process of tumor cells in vitro.Qualitative analysis of imaging data showed that the migration of MCF-7 cell lines in matrigel was determined by the concentration gradient distribution direction of chemokine and presented as the amoeboid-like migration mode.The proportion and migration velocity of MCF-7 cells could be quantified by the quantitative analysis of cell migration process.The inhibition ability of matrix metalloproteinase inhibitors(Batimastat)and adenosine triphosphatase inhibitors(Blebbistation)on the 3D migration behavior of MCF-7 cells was found to be different.Conclusion This device can be used for in-depth analysis of tumor cell migration and its mechanism and for evaluating the efficacy of anti-metastatic drugs.

Infection rate of Giardia duodenalis, Cryptosporidium spp. and Enterocytozoon bieneusi in cashmere, dairy and meat goats in China.

Cryptosporidiosis, microsporidiosis, and giardiasis contribute significantly to the high burden of zoonotic diarrhea worldwide. Goats constitute an important species in animal agriculture by providing cashmere wool, meat, and dairy products for human consumption. However, zoonotic pathogens with the potential to cause morbidity and to degrade production have been reported frequently in goats recently. The present study examined 629 fecal specimens from goats, including 315 cashmere goats, 170 dairy goats and 144 meat goats, in multiple cities of Shaanxi and Henan provinces, northwestern and central China, to investigate the infection rate and species/assemblages/genotypes of Giardia duodenalis, Cryptosporidium spp. and Enterocytozoon bieneusi. Of these samples, 274 (43.6%) were positive for three zoonotic pathogens, including 80 (12.7%), 104 (16.5%) and 179 (28.5%) for G. duodenalis, Cryptosporidium spp. and E. bieneusi, respectively. Infections with G. duodenalis, Cryptosporidium spp. and E. bieneusi existed in meat, dairy and cashmere goats, with the highest infection rate of each pathogen being observed in meat goats. DNA sequencing of the SSU rRNA gene from 104 Cryptosporidium-positive specimens revealed existence of Cryptosporidium xiaoi, and the zoonotic parasites Cryptosporidium parvum and Cryptosporidium ubiquitum. Genotyping of G. duodenalis based on the triosephosphate isomerase (TPI) gene identified parasites from zoonotic assemblage A in four cashmere goats and the animal-adapted assemblage E in a group of 76 goats that included cashmere, dairy and meat animals. Polymorphisms in the ribosomal internal transcribed spacer characterized E. bieneusi genotype CHG1 and a novel genotype named as SX1 in both dairy and cashmere goats, genotypes CHS7 and COSI in meat goats, the genotype CHG2 in dairy goats, and the human-pathogenic genotype BEB6 in dairy and meat goats. This is the first detailed study to compare infection rate of the zoonotic protozoan pathogens in cashmere, dairy and meat goats in China. Our research discovered Cryptosporidium spp. and E. bieneusi infections, each with zoonotic potential in meat goats, and G. duodenalis and Cryptosporidium spp. in cashmere goats raising a significant public health concern.