[Progress of metagenomics next-generation sequencing in the detection of drug-resistant phenotypes of Gram-negative bacteria]

The ongoing spread of drug-resistant bacterial infections poses a significant threat to public health, and early diagnosis and targeted treatment are the keys to successful treatment. Traditional bacterial culture and drug susceptibility testing is time-consuming and insensitive, and cannot meet the needs of clinical diagnosis and treatment, so molecular detection technologies, such as metagenomics next-generation sequencing, have become a new research direction. This article reviewed recent advances in high-throughput sequencing for the diagnosis and treatment of drug resistance in Gram-negative bacteria.

Effects of chronic intranasal dantrolene on nasal mucosa morphology in mice

OBJECTIVE

We have previously shown that the intranasal administration of dantrolene ameliorated cognitive dysfunction in the 5XFAD mouse model of Alzheimer's disease. This study examines the morphology of the nasal mucosa after 10 months of intranasal dantrolene in 5XFAD mice.

MATERIALS AND METHODS

5XFAD mice were either treated with intranasal dantrolene (5 mg/kg, 3 times/wk) from 2 months to 12 months of age or given no treatment at all. The mice were euthanatized at 12 months of age and the snouts were processed for histological examination. The morphology of the nasal mucosa was assessed and compared between the two groups.

RESULTS

There were no significant differences in the thickness of the olfactory epithelium or the proportion of the thickness of the glandular layer to the wall of mucosa and submucosa in the nasal passages.

CONCLUSIONS

Long-term intranasal administration of dantrolene did not significantly change the nasal mucosa morphology in 5XFAD mice.

The neuroprotective effects of Galectin-1 on Parkinson's Disease via regulation of Nrf2 expression

OBJECTIVE

Parkinson's disease (PD) is one of the neurodegenerative diseases. Galectin-1 (Gal-1) is expressed in the central nervous system. Our study sought to explore the neuroprotective effect of Gal-1 in 1‑methyl‑4‑phenyl pyridine ion (MPP+)-induced cytotoxicity on SH-SY5Y cells.

MATERIALS AND METHODS

SH-SY5Y cells were cultured in vitro, pretreated with Gal-1, and then exposed to MPP+. Thereafter, the generation of reactive oxygen species (ROS) in SH-SY5Y cells was investigated. The effects of Gal-1 on DNA breakage, cell damage (release of lactate dehydrogenase (LDH)), viability, and apoptosis in SH-SY5Y cells were examined by comet assay, LDH assay, WST-1 assay, and flow cytometry, respectively. Additionally, the regulatory effect of Gal-1 on Nrf2 expression was examined by western blot. Zebrafish embryos were pretreated with Gal-1 and then exposed to MPP+. The locomotor ability of zebrafish larvae was then investigated.

RESULTS

MPP+ induced the production of ROS in cells, which can be alleviated by pretreatment with Gal-1. Gal-1 protected cells from MPP+-induced cytotoxicity by preventing DNA breakage and cell injury. Gal-1 inhibited apoptosis in SH-SY5Y cells. The neuroprotective effect of Gal-1 could be abolished when Nrf2 expression knockdown. Moreover, exposure to MPP+ decreased the locomotor activity of zebrafish, which was attenuated by pretreatment with Gal-1.

CONCLUSIONS

Our study demonstrated that the administration of Gal-1 could protect neurons from cellular stress by preventing apoptosis and eliminating ROS. Moreover, the neuroprotective effect of Gal-1 in neuronal cells could be related to the activation of Nrf2 expression. Therefore, Gal-1 could be a promising strategy for treating PD.

Geniposidic Acid Confers Neuroprotective Effects in a Mouse Model of Alzheimer's Disease through Activation of a PI3K/AKT/GAP43 Regulatory Axis

BACKGROUND

Alzheimer's disease (AD) is a major cause of dementia, which is a growing global health problem and has a huge impact on individuals and society. As the modifying role of geniposidic acid (GPA) has been suggested in AD, this study sets out to determine if and how GPA treatment affects AD progression in mice.

METHODS

Potential downstream target genes of GPA during AD were identified by bioinformatics analysis, revealing GAP43 as a primary candidate protein. Then, mPrP-APPswe/PS1De9 AD transgenic mice were treated with GPA via intragastric administration. This allowed for gain- and loss-of-function assays of candidate proteins being carried out with or without GPA treatment, after which behavioral tests could be conducted for mice. Cortical neuron apoptosis was measured by TUNEL staining, Amyloid β-protein (Aβ) expression in cerebral cortex by Thioflavin-s staining, and Aβ, IL-1β, IL-6, IL-4 and TNF-α levels in cerebral cortex by ELISA. GAP43 expression in cerebral cortex of mice was detected by immunohistochemistry. Primary cortical neurons of embryonic mice were isolated and induced by Aβ1-42 to construct AD cell model. Cell viability was assessed by CCK-8, and axon growth by immunofluorescence.

RESULTS

GPA administration significantly improved the cognitive impairment, reducing Aβ accumulation and neuronal apoptosis in AD mice, and alleviated inflammation and axonal injury of Aβ1-42-induced neurons. GAP43 was shown experimentally to be the target of GPA in AD. Silencing of GAP43 repressed the neuroprotective effect of GPA treatment on AD mice. GPA elevated GAP43 expression via PI3K/AKT pathway activation and ultimately improved nerve injury in AD mice.

CONCLUSION

GPA activates a PI3K/AKT/GAP43 regulatory axis to alleviate AD progression in mice.

Measurement of the Sixth-Order Cumulant of Net-Proton Multiplicity Distributions in Au+Au Collisions at sqrt[s_{NN}]=27, 54.4, and 200 GeV at RHIC

According to first-principle lattice QCD calculations, the transition from quark-gluon plasma to hadronic matter is a smooth crossover in the region μ_{B}≤T_{c}. In this range the ratio, C_{6}/C_{2}, of net-baryon distributions are predicted to be negative. In this Letter, we report the first measurement of the midrapidity net-proton C_{6}/C_{2} from 27, 54.4, and 200 GeV Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). The dependence on collision centrality and kinematic acceptance in (p_{T}, y) are analyzed. While for 27 and 54.4 GeV collisions the C_{6}/C_{2} values are close to zero within uncertainties, it is observed that for 200 GeV collisions, the C_{6}/C_{2} ratio becomes progressively negative from peripheral to central collisions. Transport model calculations without critical dynamics predict mostly positive values except for the most central collisions within uncertainties. These observations seem to favor a smooth crossover in the high-energy nuclear collisions at top RHIC energy.

An application research for near-surface repository of strontium-90 sorption kinetic model on mudrocks

In this study,90Sr was used as the test radionuclide to characterize the sorption kinetics and effects of initial 90Sr activity and remaining 90Sr in solid concentration were simulated for a near-surface repository. The study focused on the sorption characteristics of radionuclides in unsaturated groundwater environment (or vadose zone) is the important information for investigating the near-surface disposal of intermediate and low-level radioactive waste (ILLW). Moreover, the 90Sr sorption experiments reached equilibrium within 56 h, which fit to the first order sorption kinetic model, and the remaining 90Sr in mudrock samples showed obvious sorption equilibrium hysteresis, which fit to the second order sorption kinetic model. Before reaching the maximum sorption capacity, the sorption rate constant increases with 90Sr increasing; the distribution coefficient (Kd) of 56 h decreases with the remaining 90Sr decreasing. In addition, it showed that the slow sorption process dominated before the sorption reaches equilibrium. In fact, a reliable safety assessment methodology for on-going near-surface repository required a lot of the radionuclides parameters with local environment including the radionuclides sorption/desorption rate constant and maximum sorption capacity.

[Debulking strategy of endovascular treatment for lower extremity artery lesions]

Objective: To explore the debulking strategy of lower extremity artery lesions. Methods: Retrospectively analyzed the clinical data of 101 patients underwent debulking therapy at Department of Vascular Surgery,Zhongshan Hospital,Fudan University from June 2019 to June 2020.There were 74 males and 27 females,aged (73.2±11.7)years (range:35 to 93 years).There were 31 cases in Rutherford class 3,39 cases in class 4 and 31 cases in class 5. Hypertension occurred in 72 patients. One hundred and forty lesions were treated in 101 patients. Among them, there were 13 lesions(9.3%) in iliac artery,72 lesions(51.4%) in superficial femoral artery,41 (29.3%) lesions in popliteal artery,10 lesions(7.1%) in tibiofibular trunk,and 4 lesions(2.9%) in below the knee artery.Percutaneous mechanical thrombectomy (PMT) was mainly used in acute thrombosis,excimer laser ablation (ELA) was mainly used for chronic in-stent restenosis and chronic stenosis or totally occlusive lesions,while directional atherectomy (DA) was mainly used for short calcified lesions. Results: All of the patients underwent debulking therapy. Eighty-two lesions(58.6%,82/140) were treated by PMT, 56 (40.0%,56/140) were treated by ELA,and 2 (1.4%,2/140) were treated by DA.The ankle-brachial index of the patient was 0.44±0.19 before surgery, 0.87±0.17 immediately after surgery (t=-16.26, P<0.01), and 0.81±0.20 at 6 months after surgery(t=-14.67,P<0.01),and 0.79±0.15 (t=-14.12,P<0.01) at 12 months after surgery. At 12 months,the primary patency was 86.1% (87/101),mortality was 5.0% (5/101), freedom from major-amputation survival rate was 93.1% (94/101),and target lesion reintervention rate was 9.9% (10/101). Conclusions: Debulking is feasible and effective to eliminate the arterial contents and maximize the acquisition of lumen.Selection of suitable debulking methods for different segments and lesions would be helpful to improve the technical success and obtain satisfactory results.

Stoichioproteomics study of differentially expressed proteins and pathways in head and neck cancer

Hypoxia is a prominent feature of head and neck cancer. However, the oxygen element characteristics of proteins and how they adapt to hypoxia microenvironments of head and neck cancer are still unknown. Human genome sequences and proteins expressed data of head and neck cancer were retrieved from pathology atlas of Human Protein Atlas project. Then compared the oxygen and carbon element contents between proteomes of head and neck cancer and normal oral mucosa-squamous epithelial cells, genome locations, pathways, and functional dissection associated with head and neck cancer were also studied. A total of 902 differentially expressed proteins were observed where the average oxygen content is higher than that of the lowly expressed proteins in head and neck cancer proteins. Further, the average oxygen content of the up regulated proteins was 2.54% higher than other. None of their coding genes were distributed on the Y chromosome. The up regulated proteins were enriched in endocytosis, apoptosis and regulation of actin cytoskeleton. The increased oxygen contents of the highly expressed and the up regulated proteins might be caused by frequent activity of cytoskeleton and adapted to the rapid growth and fast division of the head and neck cancer cells. The oxygen usage bias and key proteins may help us to understand the mechanisms behind head and neck cancer in targeted therapy, which lays a foundation for the application of stoichioproteomics in targeted therapy and provides promise for potential treatments for head and neck cancer.

[Identification of factors affecting Oncomelania hupensis density in Eastern Dongting Lake regions]

OBJECTIVE

To evaluate the impact of water pollutants, water levels and meteorological factors on the Oncomelania hupensis density in Eastern Dongting Lake regions, so as to provide insights into schistosomiasis control.

METHODS

O. hupensis snails were surveyed using a systematic sampling method in snail-infested marshlands in Eastern Dongting Lake regions from 2007 to 2014, and data pertaining to water pollutants, water levels and meteorological factors were collected. The duration of submergence and the date of the start of submergence were calculated. The snail density and its influencing factors were descriptively analyzed, and a linear mixed model was generated to examine the impacts of variables on the snail density. In addition, smooth curves were fitted to investigate the relationship between snail density and variables.

RESULTS

The snail density appeared a fluctuation in Eastern Dongting Lake regions during the period from 2007 to 2014, with the highest density on October, 2010 (52.79 snails/0.1 m²) and the lowest density on January 2009 (2.15 snails/0.1 m²). Linear mixed-model analysis showed that permanganate index, total phosphorus and the date of the start of submergence affected the snail density (t = 6.386, -2.920 and -3.892, all P values < 0.01). Smooth curve analysis revealed that the associations of the snail density with the permanganate index and total phosphorus appeared an approximately quadratic curve. After the end of April, the earlier date of the start of submergence resulted in a higher snail density.

CONCLUSIONS

Permenganate index, total phosphorus and the date of the start of submergence affect the O. hupensis snail density in Eastern Dongting Lake regions.

Experimental investigation on buffer/backfill materials for radioactive waste repository downward facing sorption additivity of cesium, strontium and cobalt with different concentrations

Buffer/backfill materials for radioactive waste disposal sites consist of pure bentonite or bentonite-rock mixtures. In this study, the batch test method was used to obtain the sorption characteristics of important radionuclides such as Cs, Sr and Co on buffer/backfill materials; i. e., mixing Wyoming MX-80 bentonite or local Taiwanese Zhi-Shin bentonite with possible host rock (argillite and granite) in different proportions (0∼100%). The distribution coefficients (Kd) for Cs, Sr and Co were obtained from the experiments. The distribution coefficient for the bentonite-rock mixtures were found, with more than 50% of mixing proportion of bentonite to argillite or granite, to have very similar values to that of pure bentonite. Furthermore, it was clearly found that the sorption of Cs, Sr and Co to bentonite-rock mixtures is decreased as ionic strength of the liquid phase is increased from 0.001M to 1M for NaCl solutions. According to the experimental results, in synthetic groundwater, it is quite convenient and helpful to assess the distribution coefficients (Kd) of Cs, Sr and Co for buffer/backfill materials using batch sorption experiments with bentonite-rock mixtures of fixed mixing proportions.

A high stem to leaf ratio reduced rainfall use efficiency under altered rainfall patterns in a semi-arid grassland in northeast China

Rainfall use efficiency (RUE) is crucial for understanding the changes in grassland productivity due to variations in future rainfall patterns. Recently, numerous studies have been conducted on the relationship between RUE and the amount of rainfall, but there has been little research on the influence of rainfall distribution and the interactive effect of rainfall amounts and distribution on RUE. Here, a simulated rainfall experiment was conducted to evaluate the impacts of rainfall amount (average rainfall amount (R0), 334 mm; decreased (R-) and increased (R+) rainfall amounts, 233 mm and 434 mm, respectively) and dry intervals (comprising 6-day, 9-day, 12-day, 15-day, 18-day and 21-day intervals between rainfall) on productivity and RUE in Leymus chinensis (Trin.) Tzvel., a dominant grass of the Eastern Eurasian Steppe. Our results showed that (1) for biomass production and RUE, moderate extension of dry intervals was conducive to enhancing total biomass production and RUE. The peak values of total biomass and RUE appeared during the 15-day interval for R-, and the 18-day interval for R0 and R+. (2) For biomass allocation, extension of dry intervals decreased the stem to leaf ratio (S/L) and the root to shoot ratio (R/S). (3) Further, the S/L ratio was significantly negatively correlated with RUE. These results suggest that variations in rainfall patterns can alter the RUE by changing the S/L ratio, and finally influence biomass production in L. chinensis. These findings have important implications for understanding and predicting the effect of future climate change on productivity in semi-arid grassland.

Current status and distribution of hip fractures among older adults in China

China is a middle-risk country for hip fracture at present, which differs from previous data that it was low-risk. By 2050, the total number of hip fractures in people older than 65 years is predicted to be 1.3 million.

INTRODUCTION

To assess hip fracture incidence in China and examine the heterogeneity of hip fracture in seven geographical regions of China.

METHODS

There were 238,230 hip fracture patients aged 65 years or older from 2013 to 2016 from a large national in-patients database (HQMS) involving 30.6 million hospitalizations. Taking into account the total national hospitalization rate per calendar year, we estimated the incidence of hip fracture per 100,000 residents older than 65 years in China overall and in seven geographical Chinese regions.

RESULTS

The proportion of men and women older than 65 years with hip fractures was 1.00:1.95. Between 2013 and 2016, the number of hip fractures per 100,000 people age 65+ was 278. China has vast territories; the number of hip fractures per 100,000 people over 65 years old was 202 in Northeast China and 374 in Northwest China. Northwest has higher altitude, lower population density, is less developed with lower urbanization than Northeast China which is low altitude, and highly urbanized.

CONCLUSIONS

China should no longer be regarded as a low-risk country for hip fracture. By 2050, the total number of hip fractures in people older than 65 years in China is predicted to be 1.3 million. Higher altitude areas had higher hip fracture rates than lower altitude, higher urbanized areas.

Observation of D_{s}^{±}/D^{0} Enhancement in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

We report on the first measurement of charm-strange meson D_{s}^{±} production at midrapidity in Au+Au collisions at sqrt[s_{NN}]=200  GeV from the STAR experiment. The yield ratio between strange (D_{s}^{±}) and nonstrange (D^{0}) open-charm mesons is presented and compared to model calculations. A significant enhancement, relative to a pythia simulation of p+p collisions, is observed in the D_{s}^{±}/D^{0} yield ratio in Au+Au collisions over a large range of collision centralities. Model calculations incorporating abundant strange-quark production in the quark-gluon plasma and coalescence hadronization qualitatively reproduce the data. The transverse-momentum integrated yield ratio of D_{s}^{±}/D^{0} at midrapidity is consistent with a prediction from a statistical hadronization model with the parameters constrained by the yields of light and strange hadrons measured at the same collision energy. These results suggest that the coalescence of charm quarks with strange quarks in the quark-gluon plasma plays an important role in D_{s}^{±}-meson production in heavy-ion collisions.

[Analysis of the clinical characteristics of 24 cases of hematological malignancies with SET-NUP214 fusion gene]

目的

探讨SET-NUP214融合基因在血液恶性肿瘤中的表达，分析其相关的临床及生物学特征。

方法

回顾性分析2012年1月至2018年12月北京大学人民医院诊断的24例SET-NUP214融合基因阳性血液恶性肿瘤患者的临床资料，并采用Kaplan-Meier法进行生存分析。

结果

24例患者中，急性淋巴细胞白血病（ALL）15例（T-ALL 13例，B-ALL 2例）、急性髓系白血病（AML）7例，T/髓混合急性白血病2例。13例T-ALL患者免疫表型以CD3⁺CD2⁻为主要特征，73.3％的ALL患者伴有髓系标志表达，85.7％的AML患者表达CD7。24例患者诱导化疗完全缓解（CR）率91.7％。全部患者均接受异基因造血干细胞移植，中位随访24个月，AML和ALL的3年无复发生存（RFS）率分别为85.7％和33.3％，差异无统计学意义（P＝0.128）。比较13例SET-NUP214阳性与62例SET-NUP214阴性T-ALL患者的疗效，诱导化疗CR率分别为92.3％和93.5％（P＝0.445），诱导化疗4周CR率分别为69.2％和72.6％（P＝0.187），差异均无统计学意义。接受造血干细胞移植后，SET-NUP214阳性T-ALL患者的3年RFS率（38.5％）明显低于SET-NUP214阴性T-ALL患者（66.4％）（P＝0.028）。

结论

SET-NUP214融合基因主要见于T细胞源性血液肿瘤，伴SET-NUP214融合基因T-ALL预后较差。

[Analysis and Application of Seven Common New Psychoactive Substances of Synthetic Cannabinoids in Hair]

Objective To establish a detection method for common new psychoactive substances of synthetic cannabinoids in hair with ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）. Methods In the 1 mL of internal standard methanol solution, 20 mg hair was added. After cryogenic grinding and ultrasonic extraction, the extract was separated by ACQUITY UPLC HSS T₃ column （100 mm×2.1 mm, 1.8 μm）. The mobile phase A was aqueous solution that composed of 20 mmol/L ammonium acetate, 0.1% formic acid, and 5% acetonitrile. The mobile phase B was acetonitrile. Electrospray ionization source in positive ion mode was used for data acquisition in multi-reaction monitoring （MRM） mode. Results The seven common new psychoactive substances of synthetic cannabinoids in hair had a good linear relationship within their respective linear ranges （r>0.99）, the limits of detection were 0.5-2 pg/mg, the limits of quantification were 1-5 pg/mg, the intra-day and inter-day precisions were 0.1%-12.6%, the intra-day and inter-day accuracies were 89.2%-110.7%, the recovery rates were 52.3%-93.3%, and the matrix effects were 19.1%-95.2%. Conclusion The established method has a simple sample preparation process and high sensitivity. It is suitable for qualitative and quantitative analysis of common new psychoactive substances of synthetic cannabinoids in hair.

Romosozumab efficacy on fracture outcomes is greater in patients at high baseline fracture risk: a post hoc analysis of the first year of the frame study

This study aimed to determine the interaction between baseline FRAX^® fracture probability and romosozumab efficacy. Using an ITT approach, it was determined that the efficacy of romosozumab on clinical fracture, osteoporotic fracture, and major osteoporotic fracture is significantly greater in patients at high baseline fracture risk, when compared with placebo.

INTRODUCTION

Post hoc analyses of placebo-controlled osteoporosis treatment studies have shown significantly greater reductions of fracture incidence for higher fracture risk patients. This study determined the interaction between baseline FRAX^® fracture probability and romosozumab efficacy in the placebo-controlled first year of the phase 3 FRAME study (NCT01575834).

METHODS

Using an ITT approach, an extension of Poisson regression analysis studied the relationship between treatment, FRAX^® 10-year probability of major osteoporotic fracture (MOF, calculated without BMD) and risk of first incident fracture (adjusting for age and follow-up time). Treatment interactions considered outcomes of all clinical fractures, osteoporotic fractures, MOF, clinical vertebral fractures, and morphometric vertebral fractures. Two-sided p value of < 0.1 for the interaction between treatment and FRAX^® was considered significant.

RESULTS

Compared with placebo, romosozumab reduced the incidence of all fracture outcomes in the first year (range: 32% reduction in MOF [p = 0.07] to 80% reduction in clinical vertebral fractures [p = 0.038]). Significant interactions were observed between efficacy and baseline FRAX^® probability for composite outcomes of clinical fractures, osteoporotic fractures, and MOF (p = 0.064-0.084), but not vertebral fractures (p > 0.3). For example, romosozumab decreased all clinical fractures by 22% at the 25th centile of FRAX^® probability but the reduction was 41% at the 75th centile. Exclusion of vertebral fractures from each composite fracture outcome (i.e. only nonvertebral fractures included) showed even stronger interactions with baseline FRAX^® probability (p = 0.036-0.046).

CONCLUSIONS

Efficacy of romosozumab on clinical fracture, osteoporotic fracture, and MOF is significantly greater in patients at high baseline fracture risk compared with placebo.