BACKGROUND:There is no clear conclusion on whether the lung cancer stem cels can induce to spheroid formation and have tumorigenicity. OBJECTIVE: To observe the spheroid formation induced by human lung adenocarcinoma cel line SPC-A1 and the tumorigenic ability of lung cancer stem cels. METHODS:SPC-A1 at proliferating phase was cultured in serum-free DF12 culture medium, and then recombinant human insulin-like growth factor-1, recombinant human epidermal growth factor, and recombinant human fibroblast growth factor-10 were added to induce spheroid cels. Immune fluorescence detection and PCR amplification were done to understand the expression of stem cel associated markers. NOD-SCID immunodeficient mice were subcutaneously implanted with lung spheroid cels to observe the tumor growth.In vivo fluorescence imager was used for radiography. RESULTS AND CONCLUSION:After 5-10 days, lung spheroid cels were harvested. RT-PCR results showed that lung spheroid cels were positive for CD24, CD221, CCSP and SP-C. In addition, the lung spheroid cels and purified CD24+, CD221+ lung cancer stem cels were both positive for TTF-1 of lung stem cels, OCT4 and Nanog of embryonic stem cels and TTF-1 of Bmi-1 lung stem cels. The fluorescence detection showed that over 80% lung spheroid cels expressed CCSP and OCT4; SPC-A1 cels had the characteristics of alveolar type II cels, and also expressed SP-C protein, but only about 5% of the cels expressed CCSP and OCT4. At 50 days after subcutaneous implantation of lung spheroid cels, in vivo fluorescence imaging showed that the diameter of tumor in mice was 1 cm, indicating human lung adenocarcinoma cel line SPC-A1 can induce the spheroid formation, and lung cancer stem cels rich in the cel spheres have the tumorigenic ability.

Fungal pathogens represent an important group of human pathogenic microbes that lead to an unacceptably severe global burden especially due to exceptionally high mortality. For many fungal pathogens, they are widespread saprophytes and human host is not the exclusive niche for their proliferation. Their exceptional capability to survive and thrive within infected host likely stems from their sophisticated strategies in adaptation to diverse biotic and abiotic stressors from natural niches or predators. Among these 'environmental pathogens', Cryptococcus neoformans as a model organism claims the lives of more than half a million annually. Some recent studies indicate that cryptococcal survival both inside and outside of hosts can be coordinated by a combination of social behaviors. In this review, we describe and discuss the social behaviors employed by C. neoformans and address their significant impact on biofilm formation, sexual reproduction and pathogenicity.

Objective: To understand the situation and genotype distribution of spotted fever group rickettsia (SFGR) in the border area of Tumen River Basin in free ticks in Yanbian Korean Autonomous Prefecture (Yanbian Prefecture), Jilin Province. Methods: From April to September, 2017, ticks were collected using flagging method from Hunchun, Tumen, Helong and Longjing cities in the Tumen River basin of Yanbian Prefecture. Outer membrane protein A (ompA) was detected by Polymerase Chain Reaction (PCR), then, the species were identified by gene sequencing and analyzed systematically. The positive rate of pools and MIR(minimum infection rate per 100 ticks,MIR) of SFGR were calculated, and the difference of positive rate of pools among ticks with different characteristics was compared by Chi-square test. Results: A total of 3 079 ticks were collected and divided into 536 pools. The positive rate of pools of SFGR nucleic acid was 39.7% (213 pools). The MIR of SFGR was 6.9%.The positive rate of pools of SFGR in Dermacentor silvarum, Haemaphysalis concinna, Haemaphysalis japonica, Haemaphysalis longicornis and Ixodes persulcatus were 80.4% (41/51), 14.0% (25/179), 20.2% (18/89), 78.9% (101/128) and 25.9% (21/81), and the difference was statistically significant (P<0.001). There was statistical difference in the positive rate of pools of SFGR in developmental stages of ticks (P<0.001); the positive rate of pools of female adults, male adults, nymph and larvae were 36.4% (95/261), 34.2% (67/196), 56.3% (40/71) and 7/8, and the MIR was 7.9%, 7.7%, 4.9% and 3.5%. The five genotype was detected which was Candidatus Rickettsia longicornii, Rickettsia raoultii, Rickettsia heilongjiangensis, Candidatus Rickettsia tarasevichiae,Rickettsia monacensis and have 98%-100% homology with known gene sequences. Candidatus Rickettsia longicornii, Rickettsia raoultii, Rickettsia heilongjiangensis and Candidatus Rickettsia tarasevichiae showed close evolutionary relationship with known specie (have 98%-100% homology with known gene sequences); Rickettsia monacensis showed Far from evolutionary relationship with known species (have 98% homology with known gene sequences). Conclusion SFGR infection of ticks is common in the border areas of the Tumen River Basin. There was high diversity in SFGR species and tick species in the areas surveyed.