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991.
Sridharan Jeyamohan Rajesh Kannan Moorthy Mahesh Kumar Kannan Antony Joseph Velanganni Arockiam 《Biotechnology letters》2016,38(8):1251-1260
Objective
To investigate the effect of parthenolide on apoptosis and autophagy and to study the role of the PI3K/Akt signaling pathway in cervical cancer.Results
Parthenolide inhibits HeLa cell viability in a dose dependent-manner and was confirmed by MTT assay. Parthenolide (6 µM) induces mitochondrial-mediated apoptosis and autophagy by activation of caspase-3, upregulation of Bax, Beclin-1, ATG5, ATG3 and down-regulation of Bcl-2 and mTOR. Parthenolide also inhibits PI3K and Akt expression through activation of PTEN expression. Moreover, parthenolide induces generation of reactive oxygen species that leads to the loss of mitochondrial membrane potential.Conclusion
Parthenolide induces apoptosis and autophagy-mediated growth inhibition in HeLa cells by suppressing the PI3K/Akt signaling pathway and mitochondrial membrane depolarization and ROS generation. Parthenolide may be a potential therapeutic agent for the treatment of cervical cancer.992.
The genus Cenchrus comprises around 25 species of ‘bristle clade’ grasses. Cenchrus ciliaris (buffel grass) is a hardy, perennial range grass that survives in poor sandy soils and limiting soil moisture conditions and, due to the very same reasons, this grass is one of the most prevalent fodder grasses of the arid and semi-arid regions. Most of the germplasms of Cenchrus produce seeds asexually through the process of apomeiosis. Therefore, the lack of sufficient sexual lines has hindered the crop improvement efforts in Cenchrus being confined to simple selection methods. Many attempts have been initiated in buffel grass to investigate the various molecular aspects such as genomic signatures of different species and genotypes, molecular basis of abiotic stress tolerance and reproductive performance. Even though it is an important fodder crop, molecular investigations in Cenchrus lack focus and the molecular information available on this grass is scanty. Cenchrus is a very good gene source for abiotic stress tolerance and apomixis studies. Biotechnological interventions in Cenchrus can help in crop improvement in Cenchrus as well as other crops through transgenic technology or marker assisted selection. To date no consolidated review on biotechnological interventions in Cenchrus grass has been published. Therefore we provide a thorough and in depth review on molecular research in Cenchrus focusing on molecular signatures of evolution, tolerance to abiotic stress and apomictic reproductive mechanism. 相似文献
993.
994.
Wojciech Barczak Pawel Golusiński Lukasz Luczewski Wiktoria M. Suchorska Michal M. Masternak Wojciech Golusiński 《Biotechnology letters》2016,38(10):1665-1672
Head and neck squamous cell carcinoma is the sixth leading cause of cancer worldwide. The most common risk factors are carcinogens (tobacco, alcohol), and infection of the human papilloma virus. Surgery is still considered as the treatment of choice in case of head and neck cancer, followed by a reconstructive surgery to enhance the quality of life in the patients. However, the widespread use of artificial implants does not provide appropriate physiological activities and often cannot act as a long-term solution for the patients. Here we review the applicability of multiple stem cell types for tissue engineering of cartilage, trachea, vocal folds and nerves for head and neck injuries. The ability of the cells to self-renew and maintain their pluripotency state makes them an attractive tool in tissue engineering. 相似文献
995.
Xiaobo Dong Haiyun Li Yucheng Jiang Mancheng Hu Shuni Li Quanguo Zhai 《Biotechnology letters》2016,38(9):1483-1491
Objectives
To degrade enzymatically bisphenol A (BPA) that causes serious environmental concerns and is difficult to be degraded by chemical or physical methods.Results
BPA (150 mg l?1) was completely degraded by chloroperoxidase (CPO)/H2O2 within 7 min at room temperature, atmospheric pressure with the enzyme at 6 μg CPO ml?1. The degradation products were identified by HPLC–MS, which suggested involvement of multiple steps. Enzymatic treatment followed by existing bioremediation technologies (activated sludge) enhanced removal of COD from 9 to 54 %. Using an ecotoxicity evaluation with Chlorella pyrenoidosa, the degradation products had a lower toxicity than BPA.Conclusion
BPA can be degraded rapidly and efficiently under mild conditions with chloroperoxidase at 6 μg ml?1. The degradation products had a lower toxicity than BPA.996.
Long Jin Hai-Ying Zhu Qing Guo Xiao-Chen Li Yu-Chen Zhang Guang-Lei Zhang Xiao-Xu Xing Mei-Fu Xuan Qi-Rong Luo Xi-Jun Yin Jin-Dan Kang 《Biotechnology letters》2016,38(9):1433-1441
Objective
To examine the effect of PCI-24781 (abexinostat) on the blastocyst formation rate in pig somatic cell nuclear transferred (SCNT) embryos and acetylation levels of the histone H3 lysine 9 and histone H4 lysine 12.Results
Treatment with 0.5 nM PCI-24781 for 6 h significantly improved the development of cloned embryos, in comparison to the control group (25.3 vs. 10.5 %, P < 0.05). Furthermore, PCI-24781 treatment led to elevated acetylation of H3K9 and H4K12. TUNEL assay and Hoechst 33342 staining revealed that the percentage of apoptotic cells in blastocysts was significantly lower in PCI-24781-treated SCNT embryos than in untreated embryos. Also, PCI-24781-treated embryos were transferred into three surrogate sows, one of whom became pregnant and two fetuses developed.Conclusion
PCI-24781 improves nuclear reprogramming and the developmental potential of pig SCNT embryos.997.
998.
Qaiser Jamal Iftikhar Ahmed Shafiq Ur Rehman Saira Abbas Kil Yong Kim 《Geomicrobiology journal》2016,33(1):1-9
The coal fields of Pakistan and their microbiology have not been fully explored. Therefore, a study was conducted on the coal mines of Dara Adam Khel located in the Federally Administered Tribal Areas of Pakistan. For this purpose, sampling was done from nine different mines with varying depths. A total of 32 bacterial strains were isolated and their colony size, form, texture, color, margin, elevation and opacity were noted. The majority of the strains (75%) were found Gram negative. The bacterial strains were then characterized in detail by different biochemical tests including catalase, citrate, oxidase, indole, triple sugar iron, motility, methyl red-Vogues Proskeur, nitrate reduction and phenylalanine deaminase, and an enormous physiological diversity was observed. The Gram positive strains were further characterized on molecular level using 16S rRNA gene amplification and sequence analysis. Based on molecular analysis, seven strains were identified as Bacillus tequilensis, B. cereus, Janibacter melonis, Kocuria atrinae, B. anthracis, K. rosea and B. simplex. The other two strains (strains 6 and 41) had molecular similarity of only 98% and 97% with Brachybacterium spp. and Arthrobacter spp. respectively. The phylogenetic analysis further suggested that the strains 6 and 41 may be potential candidates for novel species; however, further work is needed for confirmation. 相似文献
999.
1000.
Ángel Alberto Puig-Lagunes Domingo Canales-Espinosa Ariadna Rangel-Negrín Pedro Américo D. Dias 《International journal of primatology》2016,37(6):656-670
It is essential to document habitat occupancy patterns and population structure to facilitate the survival of primates in areas of anthropogenic disturbance. The overlapping of the Nearctic and Neotropical regions in the Olmec region of Mexico make this area particularly important as part of a natural biological corridor that harbors a high number of endemic species and connects the Atlantic and Pacific coastal plains. We surveyed Alouatta palliata mexicana (Mexican mantled howlers) in a 300-km2 area to determine if fragment occupation and subpopulation structure were related to the spatial attributes of the fragments. We measured the fragment size and shape as well as the distances to the nearest road, human settlement, agricultural field, and nearest neighboring fragment. During 1 year (ca. 4500 fieldwork hours) we surveyed 48 fragments, 17 of which were occupied, and counted 198 howlers. Larger fragments that were farther from agricultural activities were more likely to be occupied. Subpopulation size and number of individuals in all age–sex classes increased in larger fragments that were closer to other fragments. We found more females and juveniles, as well as more females per male in fragments that were farther from roads and we found fewer immatures per female, females per male, and individuals per area in more irregular fragments. In addition, more males and immatures per female occurred in fragments that were farther from agricultural fields. The Olmec Region is located at the center of the geographic distribution of mantled howlers in Mexico, and could therefore play a fundamental role in maintaining the contact between different populations. However, our study suggests that mantled howlers are highly threatened by anthropogenic habitat disturbance in this area, mainly through the loss of their habitat and contact with humans. 相似文献