Dysfunctional circadian clock accelerates cancer metastasis by intestinal microbiota triggering accumulation of myeloid-derived suppressor cells.

Circadian homeostasis in mammals is a key intrinsic mechanism for responding to the external environment. However, the interplay between circadian rhythms and the tumor microenvironment (TME) and its influence on metastasis are still unclear. Here, in patients with colorectal cancer (CRC), disturbances of circadian rhythm and the accumulation of monocytes and granulocytes were closely related to metastasis. Moreover, dysregulation of circadian rhythm promoted lung metastasis of CRC by inducing the accumulation of myeloid-derived suppressor cells (MDSCs) and dysfunctional CD8+ T cells in the lungs of mice. Also, gut microbiota and its derived metabolite taurocholic acid (TCA) contributed to lung metastasis of CRC by triggering the accumulation of MDSCs in mice. Mechanistically, TCA promoted glycolysis of MDSCs epigenetically by enhancing mono-methylation of H3K4 of target genes and inhibited CHIP-mediated ubiquitination of PDL1. Our study links the biological clock with MDSCs in the TME through gut microbiota/metabolites in controlling the metastatic spread of CRC, uncovering a systemic mechanism for cancer metastasis.

A comprehensive review of traditional uses, phytochemistry and pharmacology of Reynoutria genus.

OBJECTIVES: The genus Reynoutria belonging to the family Polygonaceae is widely distributed in the north temperate zone and used in folk medicine. It is administered as a sedative, tonic and digestive, also as a treatment for canities and alopecia. Herein, we reported a review on traditional uses, phytochemistry and pharmacology reported from 1985 up to early 2022. All the information and studies concerning Reynoutria plants were summarized from the library and digital databases (e.g. ScienceDirect, SciFinder, Medline PubMed, Google Scholar, and CNKI). KEY FINDINGS: A total of 185 articles on the genus Reynoutria have been collected. The phytochemical investigations of Reynoutria species revealed the presence of more than 277 chemical components, including stilbenoids, quinones, flavonoids, phenylpropanoids, phospholipids, lactones, phenolics and phenolic acids. Moreover, the compounds isolated from the genus Reynoutria possess a wide spectrum of pharmacology such as anti-atherosclerosis, anti-inflammatory, antioxidative, anticancer, neuroprotective, anti-virus and heart protection. SUMMARY: In this paper, the traditional uses, phytochemistry and pharmacology of genus Reynoutria were reviewed. As a source of traditional folk medicine, the Reynoutria genus have high medicinal value and they are widely used in medicine. Therefore, we hope our review can help genus Reynoutria get better development and utilization.

Engineering of reaction specificity, enantioselectivity, and catalytic activity of nitrilase for highly efficient synthesis of pregabalin precursor.

Simultaneous evolution of multiple enzyme properties remains challenging in protein engineering. A chimeric nitrilase (BaNITM0 ) with high activity towards isobutylsuccinonitrile (IBSN) was previously constructed for biosynthesis of pregabalin precursor (S)-3-cyano-5-methylhexanoic acid ((S)-CMHA). However, BaNITM0 also catalyzed the hydration of IBSN to produce by-product (S)-3-cyano-5-methylhexanoic amide. To obtain industrial nitrilase with vintage performance, we carried out engineering of BaNITM0 for simultaneous evolution of reaction specificity, enantioselectivity, and catalytic activity. The best variant V82L/M127I/C237S (BaNITM2 ) displayed higher enantioselectivity (E = 515), increased enzyme activity (5.4-fold) and reduced amide formation (from 15.8% to 1.9%) compared with BaNITM0 . Structure analysis and molecular dynamics simulations indicated that mutation M127I and C237S restricted the movement of E66 in the catalytic triad, resulting in decreased amide formation. Mutation V82L was incorporated to induce the reconstruction of the substrate binding region in the enzyme catalytic pocket, engendering the improvement of stereoselectivity. Enantio- and regio-selective hydrolysis of 150 g/L IBSN using 1.5 g/L Escherichia coli cells harboring BaNITM2 as biocatalyst afforded (S)-CMHA with >99.0% ee and 45.9% conversion, which highlighted the robustness of BaNITM2 for efficient manufacturing of pregabalin.

[A case-control study of minimally invasive transforaminal interbody fusion with the assistance of robot and traditional fluoroscopy in the treatment of single-space lumbar disc herniation].

OBJECTIVE: To compare the safety and nail placement accuracy of fluoroscopy-assisted and robot-assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in the treatment of single-space lumbar disc herniation. METHODS: The clinical data of 52 patients with single-space lumbar disc herniation treated by MIS-TLIF from March 2019 to February 2020 were retrospectively analyzed. Among them, 24 patients were treated by robot-assisted MIS-TLIF(group A) and 28 patients were treated by fluoroscopy-assisted MIS-TLIF (group B). The intraoperative blood loss, operation time, intraoperative fluoroscopy times, preoperative and postoperative visual analogue scale(VAS), Japanese Orthopaedic Association(JOA) scores and operation-related complications were recorded in two groups. Gertzbein-Robbins grade according to CT scan was used to evaluate the nail placement after operation. Grade A and B were evaluated as satisfactory nail placement, and grade C, D, and E were evaluated as error placement. Babu's method was used to evaluate the screw's invasion to the superior articular process. RESULTS: The operation time, intraoperative blood loss and intraoperative fluoroscopy times in group A were less than those in group B(P<0.05).VAS and JOA scores of all patients at the final follow-up were significantly improved compared with those before operation(P<0.05), but there was no statistically significant difference between the groups(P>0.05). There were 96 and 112 screws in group A and group B, respectively. Three days after operation, according to the Gertzbein-Robbins grade to evaluate the nail placement accuracy, there were 90 screws of grade A, 5 of grade B, 1 of grade C, no grade D and E in group A;there were 84 screws of grade A, 16 of grade B, 8 of grade C, 4 of grade D, no grade E in group B;the difference between two groups was statistically significant(Z=-3.709, P=0.000). The satisfactory rate of screw placement in group A was 98.96% (95/96), and that of group B was 89.29% (100/112), the difference between two groups was statistically significant (χ2=8.254, P=0.004). Three days after operation, the invasion of superior facet joints by pedicle screws was evaluated according to Babu's method, including 90 screws in grade 0, 4 in grade 1, 2 in grade 2, and 0 in grade 3 in group A;86 in grade 0, 12 in grade 1, 10 in grade 2 and 4 in grade 3 in group B, and the difference was statistically significant(Z=-3.433, P=0.001). There were no serious spinal cord, nerve and vascular injuries and other operation-related complications caused by screw implantation failure in both groups. All patients were followed up from 6 to 12(9.06±1.60) months. The neurological symptoms improved well after operation. During the follow-up period, there was no recurrence of symptoms, loosening or breakage of the internal fixation. CONCLUSION: Compared with the traditional fluoroscopy-assisted MIS-TLIF, the spinal robot-assisted MIS-TLIF not only has more minimally invasive and safer, but also has higher accuracy in nail placement, lower incidence of upper articular process invasion, and more accurate decompression targets, which can be used for minimally invasive treatment of single-space lumbar disc herniation.

Vitrectomy with residual internal limiting membrane covering and autologous blood for a secondary macular hole: A case report.

BACKGROUND: Myopic foveoschisis (MF) is a common complication of pathological myopia. A macular hole (MH) usually results from the natural progression of MF and is a common complication of vitrectomy. Vitrectomy combined with residual internal limiting membrane (ILM) covering and autologous blood was effective for closing a secondary MH. CASE SUMMARY: A 52-year-old woman presented to our clinic with a complaint of blurred vision in the right eye for 7 years. Her best corrected visual acuity (BCVA) was 20/100, axial length was 25.79 mm and standard equivalent refractive error was -10.5 dioptres. Preoperative optical coherence tomography revealed foveoschisis in the right eye. Vitrectomy with fovea-sparing ILM peeling was performed. An MH developed and gradually expanded 5 mo after the initial vitrectomy. Vitrectomy with residual ILM covering and autologous blood was performed. The MH closed 3 wk after the second vitrectomy. CONCLUSION: Fovea-sparing ILM peeling can provide residual ILM for the treatment of MH secondary to vitrectomy for MF. Vitrectomy combined with residual ILM covering and autologous blood is effective for closing secondary MH and improving BCVA.

Blockade of adenosine A2A receptor alleviates cognitive dysfunction after chronic exposure to intermittent hypoxia in mice.

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is widely known for its multiple systems damage, especially neurocognitive deficits in children. Since their discovery, adenosine A2A receptors (A2ARs) have been considered as key elements in signaling pathways mediating neurodegenerative diseases such as Huntington's and Alzheimer's, as well as cognitive function regulation. Herein, we investigated A2AR role in cognitive impairment induced by chronic intermittent hypoxia (CIH). Mice were exposed to CIH 7 h every day for 4 weeks, and intraperitoneally injected with A2AR agonist CGS21680 or A2AR antagonist SCH58261 half an hour before IH exposure daily. The 8-arm radial arm maze was utilized to assess spatial memory after CIH exposures.To validate findings using pharmacology, the impact of intermittent hypoxia was investigated in A2AR knockout mice. CIH-induced memory dysfunction was manifested by increased error rates in the radial arm maze test. The behavioral changes were associated with hippocampal pathology, neuronal apoptosis, and synaptic plasticity impairment. The stimulation of adenosine A2AR exacerbated memory impairment with more serious neuropathological damage, attenuated long-term potentiation (LTP), syntaxin down-regulation, and increased BDNF protein. Moreover, apoptosis-promoting protein cleaved caspase-3 was upregulated while anti-apoptotic protein Bcl-2 was downregulated. Consistent with these findings, A2AR inhibition with SCH58261 and A2AR deletion exhibited the opposite result. Overall, these findings suggest that A2AR plays a critical role in CIH-induced impairment of learning and memory by accelerating hippocampal neuronal apoptosis and reducing synaptic plasticity. Blockade of adenosine A2A receptor alleviates cognitive dysfunction after chronic exposure to intermittent hypoxia in mice.

Risk Factors for New Vertebral Fracture After Percutaneous Vertebroplasty for Osteoporotic Vertebral Compression Fractures.

PURPOSE: To analyze the risk factors for new vertebral fractures after percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCFs). PATIENTS AND METHODS: We retrospectively reviewed the records of patients with symptomatic OVCFs who underwent PVP in our hospital, from January 2014 to January 2019. Demographic and lifestyle data on the presence of underlying chronic disease, preoperative bone mineral density, details of vertebral fractures, postoperative osteoporosis treatment, and new fracture development were collected. Patients were divided into postoperative fracture and non-fracture groups. To identify the independent risk factors for new vertebral fracture development, variables significant on univariate analysis were included in a multivariate regression model. RESULTS: Of the 2202 patients treated with PVP, 362 (16.43%) had a new postoperative vertebral fracture. All patients were followed up for >12 months (mean 14.7 months). Univariate analysis revealed no significant difference in height; body weight; preoperative bone mineral density; number of fractured vertebrae; injection volume of bone cement in a single vertebra; leakage rate of bone cement; or presence of hypertension, coronary heart disease, and chronic obstructive pulmonary disease between the fracture and non-fracture groups (P>0.05). Age, sex, smoking, alcohol consumption, diabetes mellitus, postoperative exercise, and postoperative osteoporosis treatment were associated with new vertebral fractures (all P<0.05). A multivariate analysis showed that age (odds ratio [OR]=1.212, P<0.0001), female sex (OR=1.917, P<0.0001), smoking (OR=1.538, P=0.026), and diabetes (OR=1.915, P<0.0001) were positively correlated with new vertebral fracture development, whereas postoperative exercise (OR=0.220, P<0.0001) and osteoporosis treatment (OR=0.413, P<0.0001) were negatively correlated. CONCLUSION: Elderly patients, females, and those with a history of smoking and diabetes are at high risk of new vertebral fracture after PVP. Patients should be encouraged to stop smoking and consuming alcohol, control blood glucose level, participate in sufficient physical activity, and adhere to osteoporosis treatment to prevent new vertebral fractures.

Full-Endoscopic Decompression with the Application of an Endoscopic-Matched Ultrasonic Osteotome for Removal of Ossification of the Thoracic Ligamentum Flavum.

BACKGROUND: Resection of the ossification of the thoracic ligamentum flavum (OTLF) with a high-speed burr may cause a high rate of perioperative complications, such as dural laceration and/or iatrogenic spinal cord injury. OBJECTIVES: The aim of this study was to investigate the safety and feasibility of the endoscopic-matched ultrasonic osteotome in full-endoscopic spinal surgery for direct removal of OTLF. STUDY DESIGN: Retrospective study. SETTING: All data were from Honghui Hospital in Xi'an. METHODS: This study conducted between December 2017 and December 2018, included 27 consecutive patients who met the study criteria, had single-level OTLF, and underwent full-endoscopic decompression under local anesthesia. The postoperative follow-up was scheduled at 1, 3, 6, and 12 months postoperatively. Outcomes evaluations included the Visual Analog Scale (VAS) score for lower extremity pain and the modified Japanese Orthopaedic Association (mJOA) score and improvement rate for the assessment of thoracic myelopathy. Removal of OTLF was measured by comparing the pre- and postoperative computed tomography (CT) and magnetic resonance imaging (MRI) scans. RESULTS: The operation was completed in all patients without conversion to open surgery. The operation time ranged from 65 to 125 minutes (average, 83.7 ± 12.3 minutes). All patients were followed up for 12 to 18 months, with an average follow-up of 14.3 ± 1.3 months. Satisfactory neurologic decompression was confirmed by postoperative CT and MRI, and no revision surgery was required. The VAS and mJOA scores showed statistically higher improvement at the 1-month follow-up and the last follow-up compared with the preoperative assessment (P < 0.05). According to the improvement rate at the final follow-up, 20 cases were classified as good, 6 cases were fair, and 1 case remained unchanged. LIMITATIONS: A single-center, noncontrol study. CONCLUSIONS: The endoscopic-matched ultrasonic osteotome can be considered quite safe and feasible for direct removal of OTLF during full-endoscopic spinal surgery in strictly selected patients, as this allows for effective direct decompression of OTLF while minimizing trauma and instability. In addition, because of the design characteristics of the ultrasonic osteotome, surgical complications, especially dural tears and spinal cord injury, can also be effectively controlled.

[Visual analysis of coronavirus disease 2019 (COVID-19) studies based on bibliometrics].

To analyze the development of coronavirus disease 2019(COVID-19), this study systematically retrieved relevant Chinese and English literatures from both CNKI and Web of Science database platforms by bibliometric research method and CiteSpace 5.5.R2 software to obtain information and visualize relevant literatures. A total of 695 Chinese and 446 English literatures were included in this paper. Statistics showed that China had published most of the literatures and established close cooperation with the United States and the United Kingdom. Through the analysis, Tongji Medical College of Huazhong University of Science and Technology and its affiliated hospitals published the largest number of the publications. Moreover, the highly productive journals including Journal of Traditional Chinese Medicine and The Lancet covered eight major fields, such as medicine, medical virology, radiation medicine, infectious disease, and traditional Chinese medicine. Besides, a total of 35 special COVID-19 funds were recently established to subsidize these studies. The key words and themes analysis indicated that protein structure of COVID-19, receptor targets and mechanisms of action, integration of traditional Chinese and Western medicine, screening and development of antiviral drugs from traditional Chinese medicine and Western medicine, vaccine research as well as epidemiological characteristics and prediction are current study hotspots. This study provides a reference for researchers to rapidly master main study directions of COVID-19 and screen out relevant literatures.

[Comparative of functional components, antioxidant and α-glucosidase inhibition activities between Choerospondias axillaris fruit peel vinegar and apple vinegar].

Based on the idea of plant metabolomics, ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS/MS) was used to compare the chemical composition between 6 batches of fruit vinegar brewed from Choerospondias axillaris fruit peel and 6 batches of apple vinegar purchased from 3 companies. Antioxidant and α-glucosidase inhibition activities were also tested in vitro. A total of 43 compounds were identified by reference substance, liquid chromatography-mass spectrometry(LC-MS/MS) fragmentation information or literature data. A total of 40 compounds were identified in the C. axillaris fruit peel vinegar. A total of 16 compounds were identified in apple vinegar. There were 13 common ingredients including organic acids and esters such as citric acid, 2-isopropyl malic acid, and triethyl citrate. The results of partial leastsquares-discriminant analysis(PLS-DA) indicated that they had 33 significantly different compounds such as proanthocyanidin oligomer, quercetin-3-O-rhamnoside and heptadecanoic acid. The proanthocyanidins and flavonoid glycosides in C. axillaris peel vinegar were more abundant than apple vinegar, so it had better health function than ordinary fruit vinegar. The results showed that C. axillaris fruit peel vinegar had stronger antioxidant and α-glucosidase inhibition activities in vitro. The vinegar brewed from waste C. axillaris fruit peel had more chemical ingredients than the apple vinegar. C. axillaris fruit peel vinegar had better biological activity and health function, so it had good development prospect. This study provided the scientific evidence for exploiting the C. axillaris fruit peel into high value-added products. It also provided ideas for the comprehensive development and utilization of similar Chinese medicine waste.

[Study on quality standard of gypenosides extract and Gypenosides Tablets].

In response to no national standard for Gynostemma pentaphyllum, a market survey was carried out, and 17 batches of gypenosides extract and 29 batches of Gypenosides Tablets on the market were collected. With gypenoside A as an index, the TLC qualitative identification and HPLC quantitative evaluation method of gypenosides extract and tablets was established. Based on the determination results of 17 batches of gypenosides extract and 29 batches of Gypenosides Tablets, the quality standards of gypenosides extract and tablets were formulated respectively, so as to give suggestions for improving the quality standards of gypenosides extract and tablets. Compared with the existing ministerial standards, the qualitative identification and quantitative detection of specific components were added, in order to provide scientific basis and suggestions for the revision of the quality standard of gypenosides extract and tablet preparation.

Ginsenoside Re enhances the survival of H9c2 cardiac muscle cells through regulation of autophagy.

We examined the effect of ginsenoside Re (G-Re) on autophagy in H9c2 cardiomyocytes cultured in glucose deprivation (GD). Levels of the membrane-bound autophagy-related microtubule-associated protein 1A/1B-light chain 3 (LC3) B-2 were measured via immunoblotting and immunofluorescence was conducted to assess autophagosome formation. GD H9c2 cells were treated with 100 µmol/l G-Re. Cell viability was determined in culture medium. Phosphorylated 5' AMP-activated protein kinase (AMPK)-α and mammalian target of rapamycin (mTOR) levels were measured to explore the mechanisms underlying the effects of G-Re on autophagy in GD cells. G-Re treatment inhibited autophagosome formation and may be beneficial to GD cardiomyocytes.

Erratum: Author Correction: CRISPR-Cas12a-assisted nucleic acid detection.

[This corrects the article DOI: 10.1038/s41421-018-0028-z.].

Antiaging Effects of Urolithin A on Replicative Senescent Human Skin Fibroblasts.

Although the health benefits attributed to urolithin A, such as anticancer, anti-inflammatory, and antioxidant effects, are based on numerous, diverse studies carried out in vitro, the biological effects of urolith A are still not entirely understood. In this study, we explored the biological effects of urolithin A using senescent human skin fibroblasts (HSFs) to determine whether urolithin A has any antiaging potential. Our results showed that urolithin A significantly increased type I collagen expression and reduced matrix metalloproteinase 1 (MMP-1) expression. Urolithin A also reduced intracellular reactive oxygen species, which may be partially due to activation of the Nrf2-mediated antioxidative response. These results indicate that urolithin A is a promising antiaging agent. Meanwhile, we noticed that the 50 µM urolithin A could cause changes in cell morphology and inhibition in cell proliferation, which were due to cell cycle arrest in G2/M phase. However, SA-ß-gal (senescence-associated ß-galactosidase) staining and γH2AX immunofluorescence staining showed cellular senescence status of HSFs did not change. Results of DAPI (4'6-diamidino-2-phenylindole) staining (no significant change) increased BCL2 gene expression and mitochondrial membrane potential (no significant change) after urolithin A treatment showed that the cells did not undergo apoptosis. These results provided further insights into the molecular mechanism of urolithin A. In conclusion, urolithin A showed a strong potential of antiaging.

Bergapten exerts inhibitory effects on diabetes-related osteoporosis via the regulation of the PI3K/AKT, JNK/MAPK and NF-κB signaling pathways in osteoprotegerin knockout mice.

Diabetes, as a serious metobolic disorder, poses global threat to human health. It is estimated that over 50 million individuals are already affected by diabetes. Currently, diabetes-related osteoporosis has been a research hotspot due to its high incidence rate in older individuals. Osteoprotegerin, as an important protein for the prevention of osteoporosis, has been proven to be key to the suppression of osteoporosis. Hence, the loss of function of osteoprotegerin may promote the development of osteoporosis. Bergapten, as a natural anti-inflammatory and anti-tumor agent isolated from bergamot essential oil, other citrus essential oils, and grapefruit juice, has been proven to have the ability to attenuate a number of metabolic disorders. In view of these findings, in this study, we used a high-fat diet to construct a mouse model of diabetes-related osteoporosis and a mouse model of diabetes-related osteoporosis using osteoprotegerin knockout mice. Enzyme-linked immunosorbent assay (ELISA), qPCR, western blot analysis, immunohistochemical assay, H&E staining, Oil Red O staining, Masson's staining and other biochemical analyses were used to evaluate the related signaling pathways involved in the development of diabetes-related osteoporosis. We also examined the role of osteoprotegerin in the activation of these pathways and in the development of osteoporosis, as well as the protective effects of bergapten against diabetes-related osteoporosis and on the activation of related signaling pathways. Our results revealed that in diabetes-related osteoporosis, the phosphoinositide 3-kinase (PI3K)/AKT, c-Jun N-terminal kinase (JNK)/mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways were activated and the expression levels of related indicators were increased. At the same time, osteoprotegerin knockout further promoted the activation of these pathways. By contrast, bergapten exerted effects similar to those of osteoprotegerin. Bergapten exhibited the ability to significantly inhibit RANKL-RANK signaling transduction, and to suppress the activation of the PI3K/AKT, JNK/MAPK and NF-κB signaling pathways, thus protecting trabecular structure and decreasing osteoclastogenic differentiation.

[Comparison of Different Pretreatment Methods for DNA Extraction from Teeth].

OBJECTIVE: To compare the concentration of teeth DNA extracted by three different pretreatment methods and to explore a simple, economical and practical pretreatment method with high concentration of extracted DNA from teeth. METHODS: A total number of 21 molars were collected from 7 corpses. The pretreatment of 3 molars from each individual was randomly performed by tooth crumb method, ball-milling method and liquid nitrogen milling method and 50 mg tooth crumb was weight and DNA was extracted by AutoMate Express forensic DNA extraction system. Subsequently, the concentration of DNA and corresponding STR genotyping of three methods were compared. RESULTS: The DNA concentration extracted by tooth crumb method, ball-milling method and liquid nitrogen milling method was 0.055 6-1.989 1 ng/µL, 0.036 6-1.175 6 ng/µL and 0.037 8-1.249 0 ng/µL, respectively. The DNA concentration obtained by tooth crumb method was higher (P < 0.05) and the success rate of STR genotyping was high. CONCLUSION: Combined with AutoMate Express forensic DNA extraction system, tooth crumb method is an efficient and feasible method to extract DNA from teeth, which can be applied in forensic practice.

[Stability analysis of allelopathic effects of Panax notoginseng on main crops by AMMI model].

This paper is aimed to study the differences of allelopathic effects of Panax notoginseng under different allelopathic chemicals resources and selection of appropriate rotation crops. The additive main effects and multiplicative interaction ( AMMI) model had been used to evaluate the stability of allelopathic effects of P. notoginseng on the varieties of corn, wheat and rice properly. The model could use not only to evaluate the stability of non-regional trial data but also explore the interaction between the rotation crop genotypes and donor substances more efficiently. Meanwhile, correspondence analysis can be used in the AMMI to evaluate genotype stability and donor substances. Ejingza No. 1 (g6) had stronger allelopathic effects with high stability, but Yunrui No. 1 (g9) which was appropriate rotation crop genotype, had weaker allelopathic effects with high stability. These findings will aid in choosing appropriate rotation crops and establishing proper rotation system.

[Allelopathic effects of aqueous extracts from Panax notoginseng on three maize varieties (Zea mays)].

It has been showed that there were obvious obstacle effects of Panax notoginseng replanting. Crop rotation was the main effective technique to overcome the obstacle. To find a reasonable crop rotation system for P. notoginseng, aqueous extracts from root, stem and leaf of P. notoginseng were analyzed for allelopathic effect on three maize varieties (which are often grown in regions where P. notoginseng grown). The main results were as follows: (1) Allelopathic effect of P. notoginseng stem and leaf extracts on the three other tested plants was stronger than that of root extracts; (2) Corn was more vulnerable to the effects of allelochemicals at seedling stage than at germination stage, and the corn root was more sensitive than aerial part to allelochemicals; (3) Lusan No. 3 and Yunrui No. 1 showed resistance to P. notoginseng allelopathy, with respective comprehensive sensitivity indexes (M3) of - 0.089 3 and -0.159 2, while Bainuo No. 1 is sensitive at M3 = -0.261 0. It then can be concluded that Lusan No. 3 and Yunrui No. 1 may be an alternative rotation plants for overcoming P. notoginseng continuous cropping obstacle.

Genetic polymorphism of 17 Y-STR loci in Han Chinese living in Lanzhou.

The genetic polymorphism across 17 Y-STR loci in a population of Han Chinese in Lanzhou was investigated. Haplotypes and allele frequencies for the 17 Y-chromosomal STRs loci DYS456, DYS389I, DYS390, DYS389II, DYS458, DYS19, DYS385a/b, DYS393, DYS391, DYS439, DYS635, DYS392, Y GATA H4, DYS437, DYS438 and DYS448 were determined in 500 healthy unrelated autochthonous males from Lanzhou. The results showed that no shared haplotypes were observed. Gene diversity values ranged from 0.3987 (DYS391) to 0.9740 (DYS385a,b). It was concluded that these loci will be very useful for human identification in forensic cases and paternity tests within the Han Chinese population inhabiting Lanzhou.