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This study evaluated the radiosensitising effect of niraparib; a poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitor on HeLa cervical cancer cells in nude mice and explored its possible mechanism. Twenty-four 3–5-week-old female BALB/c nude mice, inoculated with HeLa cells into the right hind leg, were randomly assigned into eight groups with three mice per group and treated. The tumour volume was significantly reduced under niraparib + radiotherapy combination as compared to monotherapy and untreated mice. The tumour growth was significantly delayed by 23.33–39 days when treated with combination therapy (p<.05). Further, univariate analysis revealed prolonged time for tumour growth when radiotherapy was followed by niraparib (I.G.) rather than niraparib (I.P.) (p=.003). Combination therapy reduced levels of PARP-1 precursor, PARP-1 splicer, PAR and RAD51 protein with high expression of γ-H2AX/CC3 and low expression of Ki-67. Niraparib in combination with radiotherapy can enhance the formation of DNA double strand breaks in HeLa cells and up regulate the expression of γ-H2AX/CC3. What is already known on this subject? Asia has the highest incidence of cervical cancer (58.2%). Poly(adenosine diphosphate-ribose) polymerases (PARPs) are family of enzymes involved in single-strand break (SSB) and double-strand break (DSB) repair pathways. Niraparib is an effective inhibitor of both PARP-1 and PARP-2 and has the ability to cross the blood–brain barrier. What the results of this study add? Our study demonstrated that the combination of niraparib and radiotherapy can significantly enhance the cytotoxicity induced by radiotherapy. The inhibition effect of radiotherapy combined with niraparib on the tumour growth of mice was prominent, thereby establishing the radio-sensitisation activity of niraparib. What are the implications of these findings for clinical practice and/or further research? Niraparib can improve the cytotoxic effect of radiotherapy by increasing the formation of DSBs and up regulating the expression of apoptotic protein in HeLa cells. [ABSTRACT FROM AUTHOR]

Core sediments from Keluke Lake in transitional zone between arid central Asia and monsoon Asia, provide insights into the advance-retreat history of the summer monsoon and the Westerlies. Sediment grain size and δ13C of authigenic carbonate reveal paleoclimatic evolution since 9.32 cal ka BP: a dry-cold climate in the early Holocene, a wet-cold climate in the early stage of mid-Holocene, a relatively dry-warm climate in the late stage of mid-Holocene and, a moderately wet and frequently oscillating climate after 2.5 cal ka BP. Keluke Lake was mainly controlled by the Westerlies from 9.32 to 5.8 cal ka BP, and was dominated by the East Asia monsoon during 5.8–2.5 cal ka BP. While in the late Holocene, this area was re-controlled by the Westerlies since 2.5 cal ka BP. The boundary line between the Westerlies controlled arid central Asia and monsoon Asia varied during the Holocene. When the Westerlies strengthened and the East Asian summer monsoon weakened, the boundary line may be pushed southeastward, and vice versa. Generally, the climate in this area showed a wet-cold and dry-warm variation. • 4 distinct climate stages were revealed since 9.32 ka in Keluke area.. • The boundary between arid central Asia and monsoon Asia varied in the Holocene. • The Holocene climate in Keluke area showed a wet-cold and dry-warm variation. [ABSTRACT FROM AUTHOR]

• A robust method that could authenticate D. officinale from its confusing species effectively was developed by proteomics. • 29 peptides were selected as potential biomarkers for the authentication of D. officinale. • 3 biomarkers verified were of great significance for the identification of D. officinale. • D. officinale from two different geographical regions can be distinguished by one of the peptide biomarkers. The stems of Dendrobium officinale , a well-known and expensive food material and herbal medicine in Asia, has recently suffered adulterants and counterfeits by using lower-price confusing Dendrobium species such as D. devonianum or D. transparens in the herbal market. However, robust methods that could authenticate D. officinale from its confusing species effectively are still lacking, especially for the dried samples. This study committed to discover specific peptides biomarkers for the authentication of D. officinale from the other two Dendrobium species using label-free proteomics by nanoLC LTQ Orbitrap mass spectrometry. Multivariate statistical analysis was applied to visualize the difference between the three Dendrobium species. As a result, 29 peptides among a total of 343 measurable peptides were selected to be potential biomarkers for the classification of these Dendrobium species. The validation of the representative peptide biomarkers was carried out by the synthesized peptides and 3 peptide biomarkers were found significant for the authentication of D. officinale. Further analysis showed that peptide ALGLELDLSER may also be a biomarker for the discrimination of the D. officinale originated from different geographical regions. [ABSTRACT FROM AUTHOR]