The pH value plays an important role in the bioleaching of sulphide minerals. The effect of pH values on the extracellular poly-saccharide secreted by Acidithiobacillus ferrooxidans was investigated in different phase...The pH value plays an important role in the bioleaching of sulphide minerals. The effect of pH values on the extracellular poly-saccharide secreted by Acidithiobacillus ferrooxidans was investigated in different phases of bacterial growth during chalcopyrite bioleach-ing. It is found that extracellular polysaccharide secretion from the cells attached to chalcopyrite is more efficiently than that of the free cells in the bioleaching solution. Three factors, pH values, the concentration of soluble metal ions, and the bacterial growth and metabolism, affect extracellular polysaccharide secretion in the free cells, and are related to the bacterial growth phase. Extracellular polysaccharide secretion from the attached cells is mainly dependent on the pH value of the bacterial culture.展开更多
In order to investigate the effects of processing pH stimulation on bioleaching of chalcopyrite by moderate thermophiles,copper leaching rates and the dynamics of microbial community structures of free and attached ce...In order to investigate the effects of processing pH stimulation on bioleaching of chalcopyrite by moderate thermophiles,copper leaching rates and the dynamics of microbial community structures of free and attached cells were monitored. The results indicated that when the processing pH values were respectively adjusted to 1.0 and 3.0 on day 14, both free and attached cells experienced an adaptive phase. Meanwhile, the copper leaching rates were 86.9% and 64.0%,respectively, as opposed to a copper leaching rate of 87.5% in the control group without pH stimulation. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis suggested that pH stimulation imposed less impact on the attached organisms than on the free cells, indicating that the attached cells were more resistant to processing pH stimulation than the free cells. Furthermore, adjusting processing pH to 3.0 significantly disrupted both free and attached microbial communities, and the bioleaching system could not recover to the normal status as the control group.展开更多
BACKGROUND The female genital tract is an uncommon site of involvement for extra-genital malignancies. Ovarian metastases have been described as disseminations of lung adenocarcinoma;rare cases of secondary localizati...BACKGROUND The female genital tract is an uncommon site of involvement for extra-genital malignancies. Ovarian metastases have been described as disseminations of lung adenocarcinoma;rare cases of secondary localizations in the cervix, adnexa, and vagina have also been reported in the literature. Here, we report two cases of advanced lung adenocarcinoma with female genital tract metastasis. CASE SUMMARY The first case was a 41-year-old woman with stage IV lung adenocarcinoma metastasizing to the cervix. Immunohistochemistry of the cervical biopsy specimen revealed thyroid transcription factor (TTF)-1(+), cytokeratin (CK)-7(+), and (CK)-20(-). Gene mutational analysis showed epidermal growth factor receptor (EGFR) L858R mutation in exon 21. She had a positive response to gefitinib, for both the pulmonary mass and cervical neoplasm. The second case was a 29-year-old woman who was diagnosed with stage IV lung adenocarcinoma with EGFR mutation. After 12 mo of treatment with icotinib, ovarian biopsy showed adenocarcinoma with CDX2(-), TTF-1(+++), PAX8(-), CK- 7(+++), CK-20(++), and Ki67(15%+), accompanied with EGFR 19-del mutation and T790M mutation. CONCLUSION Immunohistochemistry and gene mutational testing have greatly helped in locating the initial tumor site when both pulmonary and female genital tract neoplasms exist.展开更多
This paper describes the investigation of the secretion of extracellular polymeric substances(EPS)by an extremely thermoacidophilic archaea,Metallosphaera sedula(M.sedula),during the bioleaching of pyrite under differ...This paper describes the investigation of the secretion of extracellular polymeric substances(EPS)by an extremely thermoacidophilic archaea,Metallosphaera sedula(M.sedula),during the bioleaching of pyrite under different temperatures and discusses the relationship among the EPS secretion,its heat resistance,and its ability to bioleach pyrite.The investigation results indicate that the amount of extracellular proteins is significantly higher than the amount of extracellular polysaccharides in the extracted EPS whether free cells or attached cells;these results are quite different from the behavior of mesophilic Acidithiobacillus ferrooxidans.Although the growth of M.sedula is inhibited at 80℃,the bioleaching ability of M.sedula is only slightly lower than that at the optimum growth temperature of 72℃ because of the heat resistance mechanism based on EPS secretion.The secretion of more extracellular proteins is an important heat resistance mechanism of M.sedula.展开更多
基金financially supported by the National Ba-sic Research Priorities Program of China(No.2010CB630903)the National Nature Science Founda-tion of China(No.31200382)
文摘The pH value plays an important role in the bioleaching of sulphide minerals. The effect of pH values on the extracellular poly-saccharide secreted by Acidithiobacillus ferrooxidans was investigated in different phases of bacterial growth during chalcopyrite bioleach-ing. It is found that extracellular polysaccharide secretion from the cells attached to chalcopyrite is more efficiently than that of the free cells in the bioleaching solution. Three factors, pH values, the concentration of soluble metal ions, and the bacterial growth and metabolism, affect extracellular polysaccharide secretion in the free cells, and are related to the bacterial growth phase. Extracellular polysaccharide secretion from the attached cells is mainly dependent on the pH value of the bacterial culture.
基金Project(31200382)supported by the National Natural Science Foundation of ChinaProject(2013FJ4068)supported by the Planned Science and Technology Project of Hunan Province,ChinaProject supported by Australia CSIRO OCE Science Leader Grant
文摘In order to investigate the effects of processing pH stimulation on bioleaching of chalcopyrite by moderate thermophiles,copper leaching rates and the dynamics of microbial community structures of free and attached cells were monitored. The results indicated that when the processing pH values were respectively adjusted to 1.0 and 3.0 on day 14, both free and attached cells experienced an adaptive phase. Meanwhile, the copper leaching rates were 86.9% and 64.0%,respectively, as opposed to a copper leaching rate of 87.5% in the control group without pH stimulation. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis suggested that pH stimulation imposed less impact on the attached organisms than on the free cells, indicating that the attached cells were more resistant to processing pH stimulation than the free cells. Furthermore, adjusting processing pH to 3.0 significantly disrupted both free and attached microbial communities, and the bioleaching system could not recover to the normal status as the control group.
基金Supported by the National Natural Science Foundation of China,No.81670017
文摘BACKGROUND The female genital tract is an uncommon site of involvement for extra-genital malignancies. Ovarian metastases have been described as disseminations of lung adenocarcinoma;rare cases of secondary localizations in the cervix, adnexa, and vagina have also been reported in the literature. Here, we report two cases of advanced lung adenocarcinoma with female genital tract metastasis. CASE SUMMARY The first case was a 41-year-old woman with stage IV lung adenocarcinoma metastasizing to the cervix. Immunohistochemistry of the cervical biopsy specimen revealed thyroid transcription factor (TTF)-1(+), cytokeratin (CK)-7(+), and (CK)-20(-). Gene mutational analysis showed epidermal growth factor receptor (EGFR) L858R mutation in exon 21. She had a positive response to gefitinib, for both the pulmonary mass and cervical neoplasm. The second case was a 29-year-old woman who was diagnosed with stage IV lung adenocarcinoma with EGFR mutation. After 12 mo of treatment with icotinib, ovarian biopsy showed adenocarcinoma with CDX2(-), TTF-1(+++), PAX8(-), CK- 7(+++), CK-20(++), and Ki67(15%+), accompanied with EGFR 19-del mutation and T790M mutation. CONCLUSION Immunohistochemistry and gene mutational testing have greatly helped in locating the initial tumor site when both pulmonary and female genital tract neoplasms exist.
基金financially supported by the National Natural Science Foundation of China (Nos. 31470230, 51320105006, 51604308, and 31100173)the Youth Talent Foundation of Hunan Province of China (No. 2017RS3003)the National Science Foundation of Hunan Province of China (No. 2018JJ2486)
文摘This paper describes the investigation of the secretion of extracellular polymeric substances(EPS)by an extremely thermoacidophilic archaea,Metallosphaera sedula(M.sedula),during the bioleaching of pyrite under different temperatures and discusses the relationship among the EPS secretion,its heat resistance,and its ability to bioleach pyrite.The investigation results indicate that the amount of extracellular proteins is significantly higher than the amount of extracellular polysaccharides in the extracted EPS whether free cells or attached cells;these results are quite different from the behavior of mesophilic Acidithiobacillus ferrooxidans.Although the growth of M.sedula is inhibited at 80℃,the bioleaching ability of M.sedula is only slightly lower than that at the optimum growth temperature of 72℃ because of the heat resistance mechanism based on EPS secretion.The secretion of more extracellular proteins is an important heat resistance mechanism of M.sedula.
