Decoding Cortical Glial Cell Development / 神经科学通报·英文版

Mouse cortical radial glial cells (RGCs) are primary neural stem cells that give rise to cortical oligodendrocytes, astrocytes, and olfactory bulb (OB) GABAergic interneurons in late embryogenesis. There are fundamental gaps in understanding how these diverse cell subtypes are generated. Here, by combining single-cell RNA-Seq with intersectional lineage analyses, we show that beginning at around E16.5, neocortical RGCs start to generate ASCL1

Homeobox Gene Six3 is Required for the Differentiation of D2-Type Medium Spiny Neurons / 神经科学通报·英文版

Medium spiny neurons (MSNs) in the striatum, which can be divided into D1 and D2 MSNs, originate from the lateral ganglionic eminence (LGE). Previously, we reported that Six3 is a downstream target of Sp8/Sp9 in the transcriptional regulatory cascade of D2 MSN development and that conditionally knocking out Six3 leads to a severe loss of D2 MSNs. Here, we showed that Six3 mainly functions in D2 MSN precursor cells and gradually loses its function as D2 MSNs mature. Conditional deletion of Six3 had little effect on cell proliferation but blocked the differentiation of D2 MSN precursor cells. In addition, conditional overexpression of Six3 promoted the differentiation of precursor cells in the LGE. We measured an increase of apoptosis in the postnatal striatum of conditional Six3-knockout mice. This suggests that, in the absence of Six3, abnormally differentiated D2 MSNs are eliminated by programmed cell death. These results further identify Six3 as an important regulatory element during D2 MSN differentiation.

Prevalence and Molecular Characterization of Echinococcus granulosus Sensu Stricto in Northern Xinjiang, China

Echinococcus granulosus is an important zoonotic parasite globally causing cystic echinococcosis (CE) in humans and animals. In this study, prevalence of CE and variation of cox1 gene sequence were analyzed with isolates E. granulosus collected from different areas in northern Xinjiang, China. The survey showed that 3.5% of sheep and 4.1% of cattle were infected with CE. Fragment of cox1 was amplified from all the positive sheep and cattle samples by PCR. In addition, 26 positive samples across the 4 areas were included. The isolates were all E. granulosus sensu stricto (s.s.) containing 15 haplotypes (Hap1-15), and clustered into 2 genotypes, G1 (90.1%, 91/101) and G3 (9.9%, 10/101). Hap1 was the most common haplotype (48.5%, 49/101). Hap9 were found in humans samples, indicating that sheep and cattle reservoir human CE. It is indicate that E. granulosus may impact on control of CE in livestock and humans in the region.

Physiological characteristics of Echinococcus and their association with interventions against echinococcosis / 中华预防医学杂志

Alveolar and cystic echinococcosis are important zoonotic diseases caused by the dog/fox tapeworms of Echinococcus granulosus and E. multilocularis, which are distributed in almost whole the world. The diseases remarkably impact on the people's health and economic development of communities. Echinococcus tapeworms need two mammalian animals to complete their lifecycle. The worms undergo different developmental stages (adult, egg/oncosphere, cyst, and protoscolex). Each stage has its own distinct physiological characteristics. We summarize the characteristics and emphasize that some features that strongly impact on design of control program. Based on the lifecycle of these worms, two stages are infectious, one is egg the only stage for primarily infecting humans and intermediate host, and another stage is protoscolex, the only stage for infecting the definite hosts of the worms. Eggs are produced by the adult worms parasitized in the intestine of definite hosts. It takes 45 days for eggs becoming mature in dogs. With this feature of the tapeworm, New Zealand and Tasmania in Australia designed control program for deworming 8 times annually with an interval between deworms at 45 days. E. multilocularis takes 28-30 days in dog/fox producing mature eggs. Given that co-existence of E. granulosus and E. multilocularis in western China, a control measure so called "prepatent deworming control measure" has been used in these endemic areas with dosing worms in dogs every month. It normally takes 12-15 months for producing protosocleces in E. granulosus cysts in sheep. If meat markets attract most lambs, that is an effective measure for controlling cystic echinococcosis given that there are no protoscoleces produced from those lambs. In addition, Echinococcus has its own unique biological characteristics, such as sexual reproduction and asexual reproduction, single-cell layer structure of cyst, bidirectional development of protoscoleces induced by bile salts, and long term of infection causing host asymptomatic reaction make the parasites a models for addressing some biological and biomedical issues. And more, hydatid cyst fluid is the antigen resource for identifying diagnostic reagents; the specific gene expressed in oncospheres has been developed as an effective vaccine used for control program. With the development and application of high-throughput omics, including genomics, transcriptomics and proteomics, we can use the physiological characteristics of Echinococcus for searching diagnostic reagents, developing preventive vaccines and identify new drug targets.