The relationship between postmortem interval and protein changes in mice.

Postmortem interval (PMI) estimation is important for forensic pathological autopsy. It has been reported that there is a correlation between certain protein changes in cadavers and PMI. However, no specific protein(s) has been used to determine the PMI so far. In this study, the total protein contents of mouse liver and spleen at different time of death were measured. The data showed that they were negatively correlated with the PMI. The degradation of ß-actin was found to be positively correlated with the PMI in the liver. Additionally, proteomic technique was used to study the changes of protein expression related to PMI in the liver of mice. By using Two-dimensional electrophoresis, the expressions of four proteins were found to be significantly decreased and those of other three proteins were unchanged with the increase of PMI. Among the seven proteins, six were identified with peptide mass fingerprinting using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The three altered proteins were SBP2, ENOA, ALDH2 and three unchanged ones were 3HAO, TPIS, CATA, respectively. In the future, those unchanged proteins could be used as internal references to more accurately and reliably infer the time of death by assessing the level of changed proteins.

The relationship between intergenerational financial support and depressive symptoms among older adults: Evidence from China Health and Retirement Longitudinal Study, 2011-2018.

OBJECTIVE: Aimed to investigate the effect of intergenerational financial support on depressive symptoms among older adults over time. METHODS: Data were obtained from China Health and Retirement Longitudinal Study (CHARLS) 2011, 2013, 2015, and 2018. A finite distributed lag (FDL) model was employed, long-run cumulative effect was evaluated. 1426 respondents followed in four waves were included in FDL model. CES-D score was used to measure depressive symptoms, intergenerational financial support was defined as financial support received from older adults' children or grandchildren. Sociodemographic characteristics, health behaviors, social insurance, and social contact factors were controlled in the model. RESULTS: More than a third older adults in China had a CES-D score of 10 or higher. Intergenerational financial support has a significant long-run cumulative negative effect on older adults' depressive symptoms (CES-D scores: coef. = -0.674, P < 0.001; % with CES-D scores ≥10: Coef. = -0.154, P = 0.018). While, the intergenerational financial support in previous period exhibited a significant negative association with depressive symptoms, the 2, 3, and 4 periods did not reach statistical significance. CONCLUSIONS: Intergenerational financial support has a significant negative effect on older adults' depressive symptoms over time, while the effect may diminish. Programs need to be explored to support home-based eldercare to mitigate this diminished effect.

Plants changed the response of bacterial community to the nitrogen and phosphorus addition ratio.

Introduction: Human activities have increased the nitrogen (N) and phosphorus (P) supply ratio of the natural ecosystem, which affects the growth of plants and the circulation of soil nutrients. However, the effect of the N and P supply ratio and the effect of plant on the soil microbial community are still unclear. Methods: In this study, 16s rRNA sequencing was used to characterize the response of bacterial communities in Phragmites communis (P.communis) rhizosphere and non-rhizosphere soil to N and P addition ratio. Results: The results showed that the a-diversity of the P.communis rhizosphere soil bacterial community increased with increasing N and P addition ratio, which was caused by the increased salt and microbially available C content by the N and P ratio. N and P addition ratio decreased the pH of non-rhizosphere soil, which consequently decreased the a-diversity of the bacterial community. With increasing N and P addition ratio, the relative abundance of Proteobacteria and Bacteroidetes increased, while that of Actinobacteria and Acidobacteria decreased, which reflected the trophic strategy of the bacterial community. The bacterial community composition of the non-rhizosphere soil was significantly affected by salt, pH and total carbon (TC) content. Salt limited the relative abundance of Actinobacteria, and increased the relative abundance of Bacteroidetes. The symbiotic network of the rhizosphere soil bacterial community had lower robustness. This is attributed to the greater selective effect of plants on the bacterial community influenced by nutrient addition. Discussion: Plants played a regulatory role in the process of N and P addition affecting the bacterial community, and nutrient uptake by the root system reduced the negative impact of N and P addition on the bacterial community. The variations in the rhizosphere soil bacterial community were mainly caused by the response of the plant to the N and P addition ratio.

Effects of different Tamarix chinensis-grass patterns on the soil quality of coastal saline soil in the Yellow River Delta, China.

Construction of circumlittoral shelter forest is of great significance to maintain ecological security of coastal zones, the safety of people's lives and property in the Yellow River Delta (YRD) in China. Tamarix chinensis-grass patterns have shown obvious advantages in construction of circumlittoral shelter forest and improving the soil quality of coastal saline soil. This study aimed to explore the soil-improving effects of various Tamarix chinensis-grass community patterns and identify the best vegetation pattern for improving the soil quality in the coastal saline-alkali land. Six kinds of Tamarix chinensis-grass community patterns were selected from the saline-alkali soil of the YRD, with bare land as the control. Effects of different Tamarix chinensis-grass patterns on the coastal saline soil were evaluated using statistical methods (e.g. principal component analysis and fuzzy membership function method). The results showed that various Tamarix chinensis-grass community patterns significantly decreased the salt contents and increased the available nutrient contents in the coastal saline-alkali soil. The soil improvement effects showed obvious distinctions among the different Tamarix chinensis-grass patterns. The mixed forest-grass pattern consisting of Tamarix chinensis, Phragmites australis, and other salt-resistant grasses showed the best effects in relation to reducing salt, preventing alkalization and increasing the soil nutrients, which resulted in the lowest salt contents and the highest nutrients. Grass species play a major role in increasing soil nutrient contents, and the density of new Tamarix chinensis forest contributes greatly to the decrease of soil salt. And the more kinds of grass species are, the better improvement effects they will have. Therefore, during the construction of the circumlittoral shelter forest system in the muddy coastal zone of the YRD, it is recommended to prioritize the high density Tamarix chinensis-Phragmites australis (TPA) community pattern, and live together with other kinds of salt-resistant grasses.

Chemerin reverses the malignant phenotype and induces differentiation of human hepatoma SMMC7721 cells.

Chemerin exhibits an inhibitory effect on hepatocellular carcinoma; however, the underlying mechanism is unclear. Here, low chemerin expression was confirmed in samples of liver cancer patients and hepatoma cells. Chemerin altered hepatoma cell morphology but had no effect on normal hepatocytes. Chemerin inhibited proliferation of several human hepatoma cell lines. Real-time PCR detection of hepatocellular carcinoma markers showed that mRNA levels of albumin and A-type gamma-glutamyl transferase increased whereas those of alpha-fetoprotein, alkaline phosphatase, B-type gamma-glutamyl transferase, insulin-like growth factor II, and human telomerase reverse transcriptase decreased in chemerin-treated SMMC7721 cells. Western blotting revealed that chemerin up-regulated albumin and vimentin expressions, and downregulated alpha-fetoprotein expression. Phosphorylated STAT3 was significantly up-regulated, whereas phosphorylated ERK and AKT were significantly downregulated by chemerin. Chemerin decreased phosphorylated ERK and AKT expression and the cell proliferation induced by PI3K activator 740 Y-P but could not significantly alter phosphorylated STAT3 expression and the cell growth induced by STAT3 inhibitor NSC74859. In conclusion, chemerin reversed the malignant phenotype and induced SMMC7721 cell differentiation by inhibiting MAPK/ERK and PI3K/AKT signaling; growth inhibition by chemerin is not directly related to the JAK/STAT signaling pathway. Our study provides novel evidence that chemerin could be utilized for liver cancer treatment.

Succession of oral microbiota community as a tool to estimate postmortem interval.

The establishment of postmortem interval is one of the most important aspects of forensic expertise. Microbes may provide a novel way to estimate the postmortem intervals in order to avoid many of these limitations. The oral cavity harbors one of the most diverse microbiomes that play a key role in the decomposition of corpses. In this study, the oral bacterial community showed obvious changes in relative abundance during the process of mice decomposition. Meanwhile, at different taxonomic levels, specific bacteria were found to be significantly correlated with the postmortem interval. Linear regression models between relative abundance and the postmortem interval were constructed. Among these species, Gamma-proteobacteria and Proteus were the best ones that can be used to infer the postmortem interval, especially late postmortem interval. Therefore, we suggest that succession of oral microbial community can be developed as a forensic tool for estimating the postmortem interval.

Studies of hTERT DNA methylation assays on the human age prediction.

As an important aspect of epigenetics, DNA methylation has been proven to be suitable for forensic DNA analysis. By detecting changes in DNA methylation, it is desirable to construct a model of age patterns associated with it to infer the age of the individual. The hTERT gene methylation is closely related to tumors, but there are few reports on the relationship between hTERT gene promoter methylation and age. In this study, we utilized the methylation-specific polymerase chain reaction and real-time PCR (relative quantification and absolute quantification) approach to explore the connection between hTERT DNA methylation and age prediction. We fit three models for age prediction based on methylation assay for 90 blood samples from donors aged 1-79 years old. Among them, the model of absolute quantification of real-time enabled the age prediction with R2 = 0.9634. We verified the linear regression model with a validation set of 30 blood samples where prediction average error was 4.29 years. Generally, this reliable method improves the DNA methylation analysis of forensic samples.

Activatable near-infrared emission-guided on-demand administration of photodynamic anticancer therapy with a theranostic nanoprobe.

Development of theranostic probes that can be used to identify tumors and direct the on-demand drug administration to cancers is ongoing but remains challenging. Herein, we report a theranostic platform composed of a H2S-activated imaging probe and a light-sensitive drug. The designed probe affords advantages of H2S-activated NIR emission light-up and efficient 1O2 generation, enabling the selective visualization of H2S-rich cancers and the subsequent imaging-directed on-demand light exposure to the detected cancers while leaving normal tissues untouched. Such controllable administration of photodynamic anticancer therapy maximizes the therapeutic efficiency and minimizes side effects. This work should facilitate significant advances toward precise diagnosis and treatment of cancer.

TEMPO-Catalyzed Aminophosphinoylation of Ethers via Tandem C(sp3)-H and C(sp3)-O Bond Cleavage.

A new TEMPO-catalyzed aminophosphinoylation of ethers with amines and H-phosphine oxides was developed for the synthesis of α-aminophosphine oxides. This metal-free aminophosphinoylation reaction could be conducted under mild conditions through tandem C(sp3)-H and C(sp3)-O bond cleavage. The present method offers a facile and efficient approach to broad range of α-aminophosphine oxide derivatives in moderate to good yields with excellent functional group tolerance.

Correlation between landscape fragmentation and sandy desertification: a case study in Horqin Sandy Land, China.

The exact roles of landscape fragmentation on sandy desertification are still not fully understood, especially with the impact of different land use types in spatial dimension. Taking patch size and shape into consideration, this paper selected the Ratio of Patch Size and the Fractal Dimension Index to establish a model that reveals the association between the area of bare sand land and the fragmentation of different land use types adjacent to bare sand land. Results indicated that (1) grass land and arable land contributed the most to landscape fragmentation processes in the regions adjacent to bare sand land during the period 1980 to 2010. Grass land occupied 54 % of the region adjacent to bare sand land in 1980. The Ratio of Patch Size of grass land decreased from 1980 to 2000 and increased after 2000. The Fractal Dimension Index of grass increased during the period 1980 to 1990 and decreased after 1990. Arable land expanded significantly during this period. The Ratio of Patch Size of arable land increased from 1980 to 1990 and decreased since 1990. The Fractal Dimension Index of arable land increased from 1990 to 2000 and decreased after 2000. (2) The Ratio of Patch Size and the Fractal Dimension Index were significantly related to the area of bare sand land. The role of landscape fragmentation was not linear to sandy desertification. There were both positive and negative effects of landscape fragmentation on sandy desertification. In 1980, the Ratio of Patch Size and the Fractal Dimension Index were negatively related to the area of bare sand land, showing that the landscape fragmentation and regularity of patches contributed to the expansion of sandy desertification. In 1990, 2000, and 2010, the Ratio of Patch Size and the Fractal Dimension Index were mostly positively related to the area of bare sand land, showing the landscape fragmentation and regularity of patches contributed to the reversion of sandy desertification in this phase. The absolute values of the coefficients were the highest for grass land in the regression models, so that grass land had the most important influence on sandy desertification.