Perna canaliculus as an Ecological Material in the Removal of o-Cresol Pollutants from Soil

Soil contamination with cresol is a problem of the 21st century and poses a threat to soil microorganisms, humans, animals, and plants. The lack of precise data on the potential toxicity of o-cresol in soil microbiome and biochemical activity, as well as the search for effective remediation methods, inspired the aim of this study. Soil is subjected to four levels of contamination with o-cresol: 0, 0.1, 1, 10, and 50 mg o-cresol kg⁻¹ dry matter (DM) of soil and the following are determined: the count of eight groups of microorganisms, colony development index (CD) and ecophysiological diversity index (EP) for organotrophic bacteria, actinobacteria and fungi, and the bacterial genetic diversity. Moreover, the responses of seven soil enzymes are investigated. Perna canaliculus is a recognized biosorbent of organic pollutants. Therefore, microbial biostimulation with Perna canaliculus shells is used to eliminate the negative effect of the phenolic compound on the soil microbiome. Fungi appears to be the microorganisms most sensitive to o-cresol, while Pseudomonas sp. is the least sensitive. In o-cresol-contaminated soils, the microbiome is represented mainly by the bacteria of the Proteobacteria and Firmicutes phyla. Acid phosphatase, alkaline phosphatase and urease can be regarded as sensitive indicators of soil disturbance. Perna canaliculus shells prove to be an effective biostimulator of soil under pressure with o-cresol.     

COVID-19 cynomolgus macaque model reflecting human COVID-19 pathological conditions

The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global threat to human health and life. A useful pathological animal model accurately reflecting human pathology is needed to overcome the COVID-19 crisis. In the present study, COVID-19 cynomolgus monkey models including monkeys with underlying diseases causing severe pathogenicity such as metabolic disease and elderly monkeys were examined. Cynomolgus macaques with various clinical conditions were intranasally and/or intratracheally inoculated with SARS-CoV-2. Infection with SARS-CoV-2 was found in mucosal swab samples, and a higher level and longer period of viral RNA was detected in elderly monkeys than in young monkeys. Pneumonia was confirmed in all of the monkeys by computed tomography images. When monkeys were readministrated SARS-CoV-2 at 56 d or later after initial infection all of the animals showed inflammatory responses without virus detection in swab samples. Surprisingly, in elderly monkeys reinfection showed transient severe pneumonia with increased levels of various serum cytokines and chemokines compared with those in primary infection. The results of this study indicated that the COVID-19 cynomolgus monkey model reflects the pathophysiology of humans and would be useful for elucidating the pathophysiology and developing therapeutic agents and vaccines.

At the end of 2019, cases of infection with a novel coronavirus, later named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), that causes various respiratory symptoms expanded globally from China. On 11 March 2020, the World Health Organization declared a pandemic status based on the spread of infection worldwide and increase in the number of deaths. The outbreak of SARS-CoV-2 has resulted in a miserable reality for global health and life, and infection cases are continuing to increase worldwide. A detailed understanding of pathological conditions and development of effective therapeutic agents are needed to overcome the pandemic of diseases caused by SARS-CoV-2 infection, which has been named COVID-19. A new strategy including the development of pharmaceutical products and the use of appropriate animal models reflecting the human pathogenesis of COVID-19 is required.The common clinical features of COVID-19 are respiratory symptoms associated with pneumonia including fever, cough, myalgia, fatigue, dyspnea, and lymphopenia (1). COVID-19 symptoms range from no symptoms to severe symptoms. COVID-19 has shown severe pathogenicity in people with underlying diseases and in elderly people (2, 3). The period from onset of COVID-19 symptoms to death varies depending on the age of the patient and underlying disease status of the patient (4). Therefore, in addition to elucidating the pathological features in healthy individuals, it is necessary to elucidate the pathological conditions in patients with underlying diseases and in elderly patients.Cynomolgus monkeys (CMs), which are common laboratory animals among nonhuman primates (NHPs), show various human-like characteristics, including higher brain functions, long life span, single pregnancy, and regular menstrual periods, which are not found in other experimental animals. In the present study, COVID-19 model CMs, including healthy young CMs, elderly CMs (23 to 30 y of age, equivalent to 69 to 90 y of age in humans), and CMs with underlying diseases including diabetes and hyperlipidemia were experimentally infected with SARS-CoV-2 as animal models reflecting human pathology.     

Capacity of soil bacteria to reach the phyllosphere and convergence of floral communities despite soil microbiota variation

Leaves and flowers are colonized by diverse bacteria that impact plant fitness and evolution. Although the structure of these microbial communities is becoming well-characterized, various aspects of their environmental origin and selection by plants remain uncertain, such as the relative proportion of soilborne bacteria in phyllosphere communities. Here, to address this issue and to provide experimental support for bacteria being filtered by flowers, we conducted common-garden experiments outside and under gnotobiotic conditions. We grew Arabidopsis thaliana in a soil substitute and added two microbial communities from natural soils. We estimated that at least 25% of the phyllosphere bacteria collected from the plants grown in the open environment were also detected in the controlled conditions, in which bacteria could reach leaves and flowers only from the soil. These taxa represented more than 40% of the communities based on amplicon sequencing. Unsupervised hierarchical clustering approaches supported the convergence of all floral microbiota, and 24 of the 28 bacteria responsible for this pattern belonged to the Burkholderiaceae family, which includes known plant pathogens and plant growth-promoting members. We anticipate that our study will foster future investigations regarding the routes used by soil microbes to reach leaves and flowers, the ubiquity of the environmental filtering of Burkholderiaceae across plant species and environments, and the potential functional effects of the accumulation of these bacteria in the reproductive organs of flowering plants.

All plants are colonized by diverse prokaryotic and eukaryotic microorganisms. While root microbiota affect plant development, leaf and floral microorganisms can also provide services, such as protection against pathogens or interference with plant–insect interactions (1–4). These functional roles illustrate the importance of these microorganisms for the development and evolution of their hosts. While the diversity of bacteria and fungi colonizing leaves and flowers has been extensively explored (5–10), the environmental sources of these microorganisms and their relative contributions are still controversial (11, 12). Insights into the origin of phyllosphere bacteria will contribute to the understanding of the life cycles, ecology, and adaptation of plants and their microbiota. Various environmental sources have been suggested, and seed banks including soil are often hypothesized to be the major sources of bacteria detected in the phyllosphere (13–16). This assumption is supported by the strong resemblance between soil and leaf microbiota at the beginning of the growing season (14). However, this similarity was also observed when phyllosphere microbiota were compared with aerial communities (17). The overlap in composition between communities of the phyllosphere, soil, and roots has been used as a further argument for the large contribution by soil communities (5, 16). This last interpretation does not consider potential concurrent colonization of soil and aerial parts of plants or additional sources. Regarding floral communities, insects (e.g., pollinators) have also been suggested as important vectors for bacterial taxa, but their contribution does not suffice to explain the bacterial diversity observed in floral communities (11, 18–20). In contrast to comparative studies with naturally grown plants, experimental approaches that address the origin of the phyllosphere microbiota are still rare. A recent experimental study involved the transplantation of adult plants from one soil to another, and the resulting shifts in leaf communities suggest continued colonization of leaves by soil bacteria (13). Despite this previous work, the contribution of leaf and floral bacteria, which have the ability to migrate from the soil, is still uncertain. The influence of soil microbiota variation alone, independent of other edaphic conditions, on phyllosphere communities also remains to be addressed.Another important aspect in our understanding of plant microbiota concerns the observed differences between the bacterial communities of roots, leaves, and flowers, not only among each other but also with respect to the surrounding microbial context (5, 6, 14, 16, 17, 21–23). The observed variations have been interpreted as being due to environmental filtering exerted by leaves and flowers on the diversity of bacteria present in the environment. However, the identity of the bacteria being filtered still needs to be investigated experimentally.In the present study, we conducted an experiment to address the origin of microorganisms in the phyllosphere. The underlying rationale was that if the phyllosphere organs filter for specific bacterial groups, differences in surrounding microbial communities should not prevent the convergence of the communities. The experimental design was such that it also allowed us to evaluate the proportion of phyllosphere bacteria that can reach leaves and flowers from the soil. We asked the following questions. 1) What is the proportion of bacterial taxa detected on leaves and flowers that have the ability to reach the phyllosphere from soil? 2) Does variation in the soil microbiota alone drive bacterial community divergence in leaves? 3) Does variation in the soil microbiota alone drive bacterial community divergence in flowers? 4) Do specific organ communities converge despite microbial variations in the microbial context surrounding the plant? 5) Which taxa support these potential convergent organ communities? We conducted common-garden experiments in both gnotobiotic and open conditions (Fig. 1). In each experiment, the soil microbial communities were the only varying parameter. Soil, leaf, and floral communities were characterized by 16S ribosomal RNA (rRNA) gene profiling using 100% identity to define taxonomic units, also termed amplicon sequence variants (ASVs) (24). Unsupervised hierarchical clustering approaches coupled with bootstrap and serial rarefaction sensitivity tests were used to measure the impact of soil communities on the bacterial microbiota of leaves and flowers; in addition, the taxa underlying the convergence of floral communities were identified. We discuss our results in the context of microbial migration, environmental selection, and the ecology of Burkholderiaceae being filtered by the floral environment.Open in a separate windowFig. 1.Experimental design.     

Methods Development for the Constrained Elastic Modulus Investigation of Organic Material in Natural Soil Conditions

Compressibility is one of the most important mechanical properties of soil. The parameter that characterizes compressibility is the constrained modulus of elasticity. Knowledge of this is important to calculate the settlement of a structure foundation on peat material. According to soil classification by EN ISO 14688-2, peat is an organic soil that contains min. 20% organic matter. It is a highly organic type of soil. Peat material has large compressibility. The value of the constrained elasticity modulus for peat is ca. 400 kPa, while it may be ca 1.0–1.6 MPa for consolidated peat. Due to the extensive range of the modulus, experimental research in this field is proposed. It is suggested to load the peat material layer with an embankment and to determine its total settlement. Based on this, a program was developed to determine the settlement–strain relationship. The authors propose an approach according to two models: the first is based on constant stress distribution in the soil with an oedometer test. The second considers the variability of stresses in the soil and the influence of the loaded area. Both methods were tested based on numerical simulations, and then an experimental field in Szczecin was used. The formulae for the constrained modulus of elasticity measurement were derived; in practical conditions, a uniaxial deformation state can be used with the combination of the total settlement.     

当归根际土壤水浸液的自毒作用研究及化感物质的鉴定

目的 通过对当归根际土壤提取液的生物学试验和有机化合物的分离鉴定,探讨当归连作障碍与自毒作用的关系.方法 设置水(CK)、当归根际土水提液100、125、250、500 mg/mL共5个处理,用于当归自毒作用的生物学实验;气相色谱-质谱联用技术(GC-MS)鉴定当归根际土壤有机化合物.结果 125 mg/mL当归根际土壤水提液能显著抑制当归自身种子发芽率、发芽指数及胚根和胚芽的伸长,且随水提液浓度的升高,这种抑制作用增强.在当归根际土壤水提液中鉴定到17个化合物,包括有机酸、酮、醛、酯和烃类等化感物质,其中很多被报道是化感物质.结论 当归根际土壤水提液对自身种子萌发和幼苗生长具有明显的自毒作用,且自毒效应具有一定的浓度依赖性,推断自毒作用可能是造成当归连作障碍的原因之一.     

西洋参根际土壤微生物群落组成与多样性研究

目的:分析不同年限西洋参根际及对照土壤样品中土壤微生物功能和组成的变化,揭示西洋参根际土壤微生物生态的变化规律。方法:应用微生物对不同碳源利用的差异,在Biolog生态培养盘上培养西洋参根际土壤微生物检测土壤微生物在群落水平的生理剖面(community level physiological profiles,CLPP);应用土壤微生物PLFA(磷脂脂肪酸)法分析西洋参根际土壤微生物组成变化。同时分析了不同年限西洋参根际土壤酸碱度、有机质等土壤肥力属性。结论:本研究所选的2种西洋参种植地的土壤基本性质有较大的差别,吉林地块的pH偏酸性(5.82),北京地块土壤偏碱性(8.27),而且吉林地块土壤的有机质、速效N、速效P和全氮显著高于北京地块土壤。土壤微生物生态分析的结果在2种地块显示相似的结果,AWCD具有相似的曲线,而主成分分析可以很明显的将二至四年生西洋参根际土与对照和一年生区别开,这也就说明西洋参种植后根际土壤微生物代谢功能降低,并且微生物结构组成发生明显的变化,这些可能是造成西洋参田间病害发生的主要原因。     

土壤因子对药用白菊花活性成分含量影响研究

目的:研究土壤因子对药用白菊花活性成分的影响,筛选主导因子。方法:测定不同产地药用白菊花中水溶性浸出物、黄酮类化合物、酚类化合物和矿质元素含量,分析相应土壤化学性状和矿质元素含量,应用相关分析、逐步回归分析、通径分析、灰色关联等统计方法探讨土壤因子对药用白菊花活性成分含量的影响。结果:土壤化学性状中对药用白菊花活性成分总体影响最大的为速效磷和速效钾,其次为脲酶、磷酸酶、蔗糖酶活性和有机质;药用白菊花中矿质元素与土壤矿质元素具有良好的相关性,其中对元素磷(P)、钾(K)的富集能力较强,其次是镉(Cd)、钙(Ca)、锌(Zn)、铜(Cu),影响药用白菊花活性成分含量的土壤矿质元素主要为磷(P)和钾(K),其次是铁(Fe)、铜(Cu)、锌(Zn)。结论:土壤因子是影响药用白菊花活性成分含量的重要因素。     

土壤无机元素对黄芩无机元素及黄芩苷含量的影响

目的:探讨黄芩土壤无机元素对药材无机元素和黄芩苷含量的影响。方法:测定河北承德黄芩中黄芩苷含量、无机元素含量及黄芩根际土壤中无机元素含量,用SPSS 13.0软件对所得数据进行方差分析和相关分析。结果:黄芩对P有明显富集作用,对Zn和Se也有一定的富集。P,Zn,Se的土壤-黄芩迁移能力显著大于其他元素。黄芩中Se含量与其土壤含量显著正相关。黄芩苷与药材中P显著正相关,与Sr,Se呈显著负相关。结论:本实验所用黄芩样品中无机元素含量普遍偏低,尤以微量无机元素明显。黄芩中多数无机元素含量并不直接受制于相应的土壤含量。黄芩药材中无机元素含量与黄芩苷含量具有相关性趋势。     

林洪生教授“固本清源”理论治疗肺结节经验思想

随着CT影像学手段应用不断推广和人们健康意识的提高,肺结节的检出率较前有明显的提高。目前各项指南对其的建议以CT复查随访及手术切除为主,如何运用中医药的优势防治肺结节的发生发展是当前热点问题。林洪生教授从事恶性肿瘤中西医结合诊疗数十年,将“固本清源”引入临床治疗,取得较好的临床及科研成果。现从肺结节的病因病机、辨证用药等方面,阐述“固本清源”理论指导下中医治疗对肺结节患者的思路与方法,为中医防治肺结节提供参考。