Safety Limit Test of Heavy Metals and Pesticide Residues in the Zhuang Ethnic Medcine Herba Polygoni Chinensis from 13 Producing Areas

[Objectives]This study was conducted to determine the contents of such five heavy metals as lead(Pb),cadmium(Cd),arsenic(As),mercury(Hg)and copper(Cu)and the contents of nine kinds of organochlorine pesticide residues including total BHC(α-BHC,β-BHC,γ-BHC,δ-BHC)and total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene in the Zhuang medicine Herba Polygoni Chinensis from 13 producing areas.[Methods]The five heavy metals were determined in accordance with the second method of general rule 2341,the inductively coupled plasma mass spectrometry method,in part 4 of the 2020 edition of Chinese Pharmacopoeia;and the nine organochlorines were determined in accordance with the first method of general rule 2341,organochlorine pesticide residue determination method(chromatography),in part 4 of the 2020 edition of Chinese Pharmacopoeia.[Results]In the Herba Polygoni Chinensis from 13 origins,the lead contents were in the range of 0.50-3.28 mg/kg;the cadmium contents were in the range of 0.06-4.21 mg/kg;the arsenic contents were in the range of 0.16-6.9 mg/kg;the copper contents were in the range of 10.5-45.1 mg/kg;the mercury contents were in the range of 0.00-0.003 mg/kg;and the nine organochlorines including the total benzene hexachloride(α-BHC,β-BHC,γ-BHC,δ-BHC),total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene were all not detected.Referring to part 4 of the 2020 edition of Chinese Pharmacopoeia,the Cu and As of the Herba Polygoni Chinensis produced in Hezhou exceeded the standards,the Cu of the Herba Polygoni Chinensis produced in Wuzhou exceeded the standard,and the As of the Herba Polygoni Chinensis produced in Yulin City and Guilin City exceeded the standard.[Conclusions]This study provides safety limit test data for the development and utilization of Herba Polygoni Chinensis of the Zhuang medicine.

Research on the Development of Guangxi Zhuang and Yao Ethnic Medicine Industry

The Chinese medicine revitalization plan represented by Zhuang and Yao ethnic medicine has been incorporated into China’s and Guangxi’s overall economic and social development plans,reflecting that The Zhuang and Yao ethnic medicine industry is an important part of China’s ethnic medicine,and it is also the representative ethnic medicine industry in Guangxi.In this paper,we investigated the development of Zhuang and Yao ethnic medicine industry and its development status by consulting literature,documents and related materials and visiting relevant departments,systematically analyzed the advantages and disadvantages of the development of Guangxi Zhuang and Yao ethnic medicine industry,and put forward feasible suggestions,aiming to accelerate the healthy development of Guangxi Zhuang and Yao ethnic medicine industry and provide effective data and decision-making basis for China to formulate relevant policies.

贸易便利化对我国跨境电商发展的影响研究——基于RCEP成员国的分析

RCEP的生效标志着全球经贸规模最大、最具发展潜力的自由贸易区的正式落地,将为其成员国的外贸增长提供新动能。在疫情的冲击及贸易保护主义抬头的背景下,跨境电商仍然表现出强劲的增长韧性,但其作为新兴业态模式,仍面临着贸易非便利因素的阻碍。本文聚焦于贸易便利化以及各因素对跨境电商进出口发展的影响。运用主成分分析法建立贸易便利化综合评价体系,并对RCEP成员国2012—2019年的贸易便利化水平进行测度,比较成员国各项贸易便利化水平指标差异,随后基于修正后的引力模型对RCEP成员国2012—2019年的面板数据进行回归。研究表明,贸易便利化能够显著促进跨境电商进出口的发展,其效应要强于关税水平,且对出口端的影响更大;文化距离在跨境电商业态中的影响要强于地理距离。分指标回归的结果显示,在贸易便利化下的四个一级指标中,金融与电子商务对跨境电商发展的影响最大。基于以上实证结果,本文为中国推进RCEP贸易便利化建设提供新思路。

Metabolic and proteostatic differences in quiescent and active neural stem cells

Adult neural stem cells are neurogenesis progenitor cells that play an important role in neurogenesis.Therefore,neural regeneration may be a promising target for treatment of many neurological illnesses.The regenerative capacity of adult neural stem cells can be chara cterized by two states:quiescent and active.Quiescent adult neural stem cells are more stable and guarantee the quantity and quality of the adult neural stem cell pool.Active adult neural stem cells are chara cterized by rapid proliferation and differentiation into neurons which allow for integration into neural circuits.This review focuses on diffe rences between quiescent and active adult neural stem cells in nutrition metabolism and protein homeostasis.Furthermore,we discuss the physiological significance and underlying advantages of these diffe rences.Due to the limited number of adult neural stem cells studies,we refe rred to studies of embryonic adult neural stem cells or non-mammalian adult neural stem cells to evaluate specific mechanisms.

Arsenic and fluoride co-enrichment of groundwater in the loess areas and associated human health risks:A case study of Dali County in the Guanzhong Basin

This study aims to reveal the occurrence and origin of typical groundwater with high arsenic and fluoride concentrations in the loess area of the Guanzhong Basin—a Neogene faulted basin.Key findings are as follows:(1)Groundwater samples with high arsenic and fluoride concentrations collected from the loess area and the terraces of the Weihe River accounted for 26%and 30%,respectively,of the total samples,with primary hydrochemical type identified as HCO_(3)-Na.The karst and sand areas exhibit relatively high groundwater quality,serving as preferred sources for water supply.It is recommended that local governments fully harness groundwater in these areas;(2)groundwater with high arsenic and fluoride concentrations in the loess area and the alluvial plain of rivers in Dali County is primarily distributed within the Guanzhong Basin,which represents the drainage zone of groundwater;(3)arsenic and fluoride in groundwater originate principally from natural and anthropogenic sources;(4)the human health risk assessments reveal that long-term intake of groundwater with high arsenic and fluoride concentrations pose cancer or non-cancer risks,which are more serious to kids compared to adults.This study provides a theoretical basis for the prevention and treatment of groundwater with high arsenic and fluoride concentrations in loess areas.

Pharmacognosy Identification of Xiaohuangcao (Dendrobium loddigesi Rolfe)

[Objectives]Pharmacognosy identification was performed on Xiaohuangcao ( Dendrobium loddigesi Rolfe).[Methods]The medicinal materials were identified through original plants,characters,microscopic structure and thin-layer identification characteristics.[Results]D.loddigesi has obvious plant morphology,characters,microscopic structure and thin-layer identification characteristics.The stem of Xiaohuangcao is slender and cylindrical,and the surface is golden yellow;and the fiber bundles outside the vascular bundles are crescent-shaped or semi-circular in the stem transection.For the powder,crystal fiber can be observed;the vascular bundles are embedded with siliceous block cells;and there are more starch grains.In the thin layer chromatography,petroleum ether-ethyl acetate-butanone-glacial acetic acid (8.5∶ 3.5∶ 1.5∶ 5 d) was used as a developing solvent,and 10% sulfuric acid ethanol solution was used as a color developing agent.[Conclusions]The research results provide reference for the application of the medicinal material and the formulation of its related quality standards.

Development of a CLDN18.2-targeting immuno-PET probe for non-invasive imaging in gastrointestinal tumors

Claudin18.2(CLDN18.2)is a tight junction protein that is overexpressed in a variety of solid tumors such as gastrointestinal cancer and oesophageal cancer.It has been identified as a promising target and a potential biomarker to diagnose tumor,evaluate efficacy,and determine patient prognosis.TST001 is a recombinant humanized CLDN18.2 antibody that selectively binds to the extracellular loop of human Claudin18.2.In this study,we constructed a solid target radionuclide zirconium-^(89)(^(89)Zr)labled-TST001 to detect the expression of in the human stomach cancer BGC823CLDN18.2 cell lines.The[^(89)Zr]Zr-desferrioxamine(DFO)-TST001 showed high radiochemical purity(RCP,>99%)and specific activity(24.15±1.34 GBq/mmol),and was stable in 5%human serum albumin,and phosphate buffer saline(>85%RCP at 96 h).The EC_(50) values of TST001 and DFO-TST001 were as high as 0.413±0.055 and 0.361±0.058 nM(P>0.05),respectively.The radiotracer had a significantly higher average standard uptake values in CLDN18.2-positive tumors than in CLDN18.2-negative tumors(1.11±0.02 vs.0.49±0.03,P=0.0016)2 days post injection(p.i.).BGC823CLDN18.2 mice models showed high tumor/muscle ratios 96 h p.i.with[^(89)Zr]Zr-DFO-TST001 was much higher than those of the other imaging groups.Immunohistochemistry results showed that BGC823CLDN18.2 tumors were highly positive(+++)for CLDN18.2,while those in the BGC823 group did not express CLDN18.2().The results of ex vivo biodistribution studies showed that there was a higher distribution in the BGC823CLDN18.2 tumor bearing mice(2.05±0.16%ID/g)than BGC823 mice(0.69±0.02%ID/g)and blocking group(0.72±0.02%ID/g).A dosimetry estimation study showed that the effective dose of[^(89)Zr]Zr-DFO-TST001 was 0.0705 mSv/MBq,which is within the range of acceptable doses for nuclear medicine research.Taken together,these results suggest that Good Manufacturing Practices produced by this immuno-positron emission tomography probe can detect CLDN18.2-overexpressing tumors.

Inspired by novel radiopharmaceuticals:Rush hour of nuclear medicine

Nuclear medicine plays an irreplaceable role in the diagnosis and treatment of tumors.Radiopharmaceuticals are important components of nuclear medicine.Among the radiopharmaceuticals approved by the Food and Drug Administration(FDA),radio-tracers targeting prostate-specific membrane antigen(PSMA)and somatostatin receptor(SSTR)have held essential positions in the diagnosis and treatment of prostate cancers and neuroendocrine neoplasms,respectively.In recent years,FDA-approved serials of immune-therapy and targeted therapy drugs targeting programmed death 1(PD-1)/programmed death ligand 1(PD-L1),human epidermal growth factor receptor 2(HER2),and nectin cell adhesion molecule 4(Nectin 4).How to screen patients suitable for these treatments and monitor the therapy?Nuclear medicine with specific radiopharmaceuticals can visualize the expression level of those targets in systemic lesions and evaluate the efficacy of treatment.In addition to radiopharmaceuticals,imaging equipment is also a key step for nuclear medicine.Advanced equipment including total-body positron emission tomography/computed tomography(PET/CT)and positron emission tomography/magnetic resonance imaging(PET/MRI)has been developed,which contribute to the diagnosis and treatment of tumors,as well as the development of new radiopharmaceuticals.Here,we conclude most recently advances of radiopharmaceuticals in nuclear medicine,and they substantially increase the“arsenal”of clinicians for tumor therapy.

CLDN18.2-targeted molecular imaging and precision therapy of gastrointestinal tumors

Claudin-18.2(CLDN18.2)is a tight junction protein that is typically expressed only in normal gastric mucosal cells.When malignancy occurs,cell polarity is lost,intercellular adhesion structures are destroyed,and CLDN18.2 is therefore exposed to the surface of tumor cells[1].CLDN18.2 is specifically expressed in approximately 40%of human epidermal growth factor receptor 2(HER2)-negative gastrointestinal cancers,making it a promising emerging therapeutic target.As recently reported,zolbetuximab,an CLDN18.2 targeting antibody,has shown amazing efficacy in patients with CLDN18.2-positive and HER2-negative gastric cancers[2].In clinical practice,the assessment of CLDN18.2 expression status is crucial to the determination of treatment regimen for patients.Molecular imaging can be used as a non-invasive test for diagnosis,staging,and efficacy monitoring.The results of molecular imaging of CLDN18.2 have been published continuously,and the development of CLDN18.2 molecular probe is of great significance for the development of tumor targeted therapy(Fig.1).

Research Progress of Total Flavonoids from Plants in Trib.Lorantheae

Trib.Lorantheae is one of the important medicinal plants in traditional medicine.There are 41 genera,6 genera of which are produced in China,mainly distributed in Southwest China,South China and Central South China.There are many kinds of plants in this family,and 22 species can be used as Chinese medicinal materials in China.The branches and leaves of Trib.Lorantheae are rich in flavonoids,alkaloids,terpenoids,polysaccharides,organic acids and other functional substances,among which flavonoids are one of the important chemical components to exert pharmacological activity,and play an important role in hypoglycemic,lipid-lowering,anti-inflammatory,anti-tumor,anti-oxidation,anti-osteoporosis and so on.In this paper,the chemical composition,extraction method,component analysis and pharmacological action of flavonoids in Trib.Lorantheae plants were reviewed,in order to provide scientific reference for further development and clinical application of flavonoids in Trib.Lorantheae plants.

利用接种人体组织的SCID小鼠研究疱疹病毒的发病机理

人细胞巨化病毒(HCMV)和带状疱疹病毒(VZV)属于疱疹病毒家族。对于有免疫力的宿主,HCMV很少引起疾病症状,但对于有免疫损害和成长中的胎儿,HCMV是引起感染性疾病和死亡的主要病因。VZV感染可引起水痘和带状疱疹。由于这些种属特异性疱疹病毒不能感染其他动物,没有动物模型可用于发病机理的研究。移植了人免疫组织的严重联合免疫缺陷小鼠(SCID2hu)为这项研究提供了一个有价值的模型。我们用HCMV或VZV感染SCID2hu以调查在人胎儿胸腺Π肝脏组织的发病机理。

仿生波状前缘抑制叶栅角区分离的作用

针对压气机叶栅端区复杂的角区分离现象,仿照座头鲸特殊的胸鳍结构,对压气机的动叶片进行波状前缘改型,研究其抑制压气机角区分离的作用。数值模拟结果表明:在近设计点,波状前缘结构诱导产生的流向涡将向角区注入了高动量流体,吹除了堆积在角区的低能流体,角区低能流体沿展向的爬升高度从25%降低到了15%。角区流体的能量交换得到加强,有效降低了叶栅总压损失,提高了叶栅的通流能力,叶栅性能得到改善。

The tropical-subtropical evergreen forest transition in East Asia:An exploration

The transition from tropical to subtropical(warm temperate)evergreen forests is more clearly apparent in East Asia,fromNepal to the western Pacific coast,than elsewhere in the tropics.We review the nature of this transition and hypothesize the physical,ultimately climatic,factors thatmay maintain it,with a special focus on how the increasing instability and warming of climates will affect these forests.A primary climatic mediator of the transition is proposed,thereby offering a testable hypothesis for the climateeforest transition relationship.What is known of this transition is summarized in context of the primary climatic mediators of elevational zonation of forest formations in equatorial Asia to the tree line,in the Himalaya at the India-Indo-Burma northern tropical margin,and as both elevational and latitudinal zonation in southern China.Consequent secondary edaphic and other physical changes are described for the Himalaya,and hypothesized for southern China.The forest ecotones are seen to be primarily defined by tree floristic change,on which account changes in structure and physiognomy are determined.The montane tropical-subtropical transition in the Himalaya is narrowand observed to correlate with an as yet ill-defined frost line.A distinct tropical-subtropical transition forest is recognized in the southwest Chinamountains.There is a total change in canopy species at the Himalayan ecotone,but subcanopy tropical species persist along an elevational decline of c.400 m.The latitudinal transition in South China is analogous,but here the tropical subcanopy component extends north over ten degrees latitude,albeit in decline.The tropical-subtropical transition is uniquely clear in East Asia because here alone a tropical wet summer-dry winter monsoon extends to 35
north latitude,encompassing the subtropical evergreen forest,whereas subtropical evergreen forests elsewhere exist under drier temperate summer climate regimes.

Varicella zoster virus vaccines: potential complications and possible improvements

Varicella zoster virus(VZV) is the causative agent of varicella(chicken pox) and herpes zoster(shingles). After primary infection, the virus remains latent in sensory ganglia, and reactivates upon weakening of the cellular immune system due to various conditions, erupting from sensory neurons and infecting the corresponding skin tissue. The current varicella vaccine(v-Oka) is highly attenuated in the skin, yet retains its neurovirulence and may reactivate and damage sensory neurons. The reactivation is sometimes associated with postherpetic neuralgia(PHN), a severe pain along the affected sensory nerves that can linger for years, even after the herpetic rash resolves. In addition to the older population that develops a secondary infection resulting in herpes zoster, childhood breakthrough herpes zoster affects a small population of vaccinated children. There is a great need for a neuro-attenuated vaccine that would prevent not only the varicella manifestation, but, more importantly, any establishment of latency, and therefore herpes zoster. The development of a genetically-defined live-attenuated VZV vaccine that prevents neuronal and latent infection, in addition to primary varicella, is imperative for eventual eradication of VZV, and, if fully understood, has vast implications for many related herpesviruses and other viruses with similar pathogenic mechanisms.

Combined community ecology and floristics,a synthetic study on the upper montane evergreen broad-leaved forests in Yunnan,southwestern China

The upper montane evergreen broad-leaved forest in Yunnan occurs mainly in the zone of persistent cloud and has a discontinuous,island-like,distribution.It is diverse,rich in endemic species,and likely to be sensitive to climate change.Six 1-ha sampling plots were established across the main distribution area of the upper montane evergreen broad-leaved forest in Yunnan.All trees with d.b.h.>1 cm in each plot were identified.Patterns of seed plant distributions were quantified at the specific,generic and family levels.The forests are dominated by the families Fagaceae,Lauraceae,Theaceae and Magnoliaceae,but are very diverse with only a few species shared between sites.Floristic similarities at the family and generic level were high,but they were low at the specific level,with species complementarity between plots.Diversity varied greatly among sites,with greater species richness and more rare species in western Yunnan than central Yunnan.The flora is dominated by tropical biogeographical elements,mainly the pantropic and the tropical Asian distributions at the family and genus levels.In contrast,at the species level,the flora is dominated by the southwest or the southeast China distributions,including Yunnan endemics.This suggests that the flora of the upper montane forest in Yunnan could have a tropical floristic origin,and has adapted to cooler temperatures with the uplift of the Himalayas.Due to great sensitivity to climate,high endemism and species complementarity,as well as the discontinuous,island-like,distribution patterns of the upper montane forest in Yunnan,the regional conservation of the forest is especially needed.

Microplastic pollution in surface water and sediments of Qinghai-Tibet Plateau: Current status and causes

To study the current status and causes of the microplastic pollution in surface water of the Qinghai-Tibet Plateau,this paper compared the average microplastic abundance in sediments and surface water of the Qinghai-Tibet Plateau and the results are as follows.First,the average microplastic abundance in surface water of the independent rivers and the whole area is 247−2686 items/m^(3) and 856 items/m^(3),respectively.The average microplastic abundance in sediments of independent rivers or lakes and the whole area is 0−933 items/m^(2) and 362 items/m^(2),respectively.Meanwhile,the degree of microplastic pollution in river sediments is higher than that in lake sediments,and the rivers suffering from microplastic pollution mainly include the Brahmaputra River,Tongtian River,and Nujiang River.Second,compared with the microplastic pollution in other areas of the world,the levelof microplastic pollution in the lakes and rivers of the Qinghai-Tibet plateau is not lower than that of well-developed areas with more intensive human activities.Finally,this study suggests that relevant government departments of the Qinghai-Tibet Plateau should strengthen waste management strategies while developing tourism and that much attention should be paid to the impacts of microplastics in the water environment.

The Influence of Normal Load and Sliding Speed on Frictional Properties of Skin

The study of frictional properties of human skin is important for medical research, skin care products and textile exploi- tation. In order to investigate the influence of normal load and sliding speed on the frictional properties of skin and its possible mechanism, tests were carded out on a multi-specimen friction tester. When the normal load increases from 0.1 N to 0.9 N, normal displacement and the friction coefficient of skin increase. The friction coefficient is dependent on the load, indicating that both adhesion and deformation contribute to the friction behaviour. The deformation friction was interpreted using the plough model of friction. When sliding speed increases from 0.5 mm·s^-1 to 4 mm·s^-1, the friction coefficient increases and ＂stick-slip＂ phenomena increase, indicating that hysteretic friction contributes to the friction. The hysteretic friction was in- terpreted using schematic of energy translation during the rigid spherical probe sliding on the soft skin surface, which provides an explanation for the influence of the sliding speed on the frictional characteristics of the skin.

Tropical deciduous forest in Yunnan,southwestern China:Implications for geological and climatic histories from a little-known forest formation

In the southern mountain ranges of Yunnan province,China,deep valleys of several large rivers create rain shadows with hot dry summers,and are locally designated tropical;towards the north,notably in the Lancang(Upper Mekong)valley,these regions may experience frost during winter.The woody forest canopy of these valleys is predominantly deciduous,with evergreen elements in the north,where the canopy is open and the forest savanna-like.However,we here present tall forest with a closed deciduous canopy and semi-evergreen subcanopy observed in hot dry valleys of these rivers and their tributaries in the tropical south.The structure and physiognomy of these forests resemble the tall(moist)deciduous forest formation widespread in South Asia and Indo-Burma.Furthermore,these forests are largely composed of tropical elements at both the generic(80%)and the species level(>70%),indicating that these forests are indeed tropical.We originally hypothesized that these isolated forests represent refugia of a pre-Holocene extension of tall(moist)deciduous forest formation of South Asia and Indo-Burma.The sample plot we established to test this hypothesis confirmed that these forests share the structure and physiognomy of the tall(moist)deciduous forest formation;however,the plots also showed that these forests lack the characteristic and dominant species of the formation's Indo-Burmese range.The tree flora,in particular,indicates that both deciduous and evergreen elements are instead mostly derived from the adjacent tropical semi-evergreen forests of tropical southern China;yet they also include an important endemic element,which implies that these forests have survived as refuges possibly since the Pliocene.The exceptional representation of evergreen elements in these forests indicates that they have rarely been subject to hot fires or domestic cattle browsing,adding to the unique nature of the forests and further justifying their strict conservation.

Ocular herpes:the pathophysiology,management and treatment of herpetic eye diseases

Herpesviruses are a prominent cause of human viral disease, second only to the cold and influenza viruses. Most herpesvirus infections are mild or asymptomatic. However, when the virus invades the eye, a number of pathologies can develop and its associated sequelae have become a considerable source of ocular morbidity. The most common culprits of herpetic eye disease are the herpes simplex virus(HSV), varicella zoster virus(VZV), and cytomegalovirus(CMV). While primary infection can produce ocular disease, the most destructive manifestations tend to arise from recurrent infection. These recurrent infections can wreck devastating effects and lead to irreversible vision loss accompanied by a decreased quality of life, increased healthcare usage, and significant cost burden. Unfortunately, no method currently exists to eradicate herpesviruses from the body after infection. Treatment and management of herpes-related eye conditions continue to revolve around antiviral drugs, although corticosteroids, interferons, and other newer therapies may also be appropriate depending on the disease presentation. Ultimately, the advent of effective vaccines will be crucial to preventing herpesvirus diseases altogether and cutting the incidence of ocular complications.

Evaluation of Heavy Metals and Pesticide Residues in Dendrobium officinale Produced in Guangxi

[Objectives]To establish a method for the determination of heavy metals and pesticide residues in Dendrobium officinale produced in Guangxi and its culture substrate.[Methods]The contents of five heavy metals(Pb,Cd,As,Hg and Cu)were determined by the atomic absorption spectrophotometric(AAS)method;residues of 9 organochlorine pesticides(α-BHC,β-BHC,γ-BHC,δ-BHC,p,p′-DDT,p,p′-DDE,p,p′-DDD,o,p′-DDT and pentachloronitrobenzene)were determined by gas chromatography(GC).[Results]The contents of five heavy metals in the medicinal materials of D.officinale produced in Guangxi were 0.96,0.21,0.021 mg/kg,and not detected,and 0.35 mg/kg.The contents of five heavy metals in the culture substrate were 0.03,0.19,0.21,0.004 and 1.80 mg/kg,respectively;the content of 9 organochlorine pesticide residues in the sample was not detected.[Conclusions]The detection results of heavy metal content and organochlorine pesticide residues in D.officinale produced in Guangxi and its substrate are consistent with the limit requirements of the Chinese Pharmacopoeia.This experiment is expected to provide reliable data reference for ensuring the safety of the drug resources of D.officinale in Guangxi.