Oral administration of Nigella sativa oil attenuates arsenic-induced redox imbalance,DNA damage,metabolic distress,and histopathological alterations in rat intestine

BackgroundExposure to arsenic, a widespread environmental toxin, produces multiple organ toxicity, including gastrointestinal toxicity. Nigella sativa (NS) has long been revered for its numerous health benefits under normal and pathological states. In view of this, the present study attempts to evaluate the protective efficacy of orally administered Nigella sativa oil (NSO) against arsenic-induced cytotoxic and genotoxic alterations in rat intestine and elucidate the underlying mechanism of its action.MethodsRats were categorized into the control, NaAs, NSO, and NaAs+NSO groups. After pre-treatment of rats in the NaAs+NSO and NSO groups daily with NSO (2 ml/kg bwt, orally) for 14 days, NSO treatment was further continued for 30 days, with and without NaAs treatment (5 mg/kg bwt, orally), respectively. Various biochemical parameters, such as enzymatic and non-enzymatic antioxidants, carbohydrate metabolic and brush border membrane marker enzyme activities were evaluated in the mucosal homogenates of all the groups. Intestinal brush border membrane vesicles (BBMV) were isolated, and the activities of membrane marker enzyme viz. ALP, GGTase, LAP, and sucrase were determined. Further, the effect on kinetic parameters viz K_M (Michaelis-Menten constant) and V_max of these enzymes was assessed. Integrity of enterocyte DNA was examined using the comet assay. Histopathology of the intestines was performed to evaluate the histoarchitectural alterations induced by chronic arsenic exposure and/or NSO supplementation. Arsenic accumulation in the intestine was studied by inductively coupled plasma-mass spectroscopy (ICP-MS).ResultsNaAs treatment caused substantial changes in the activities of brush border membrane (BBM), carbohydrate metabolism, and antioxidant defense enzymes in the intestinal mucosal homogenates. The isolated BBM vesicles (BBMV) also showed marked suppression in the marker enzyme activities. Severe DNA damage and mucosal arsenic accumulation were observed in rats treated with NaAs alone. In contrast, oral NSO supplementation significantly alleviated all the adverse alterations induced by NaAs treatment. Histopathological examination supported the biochemical findings.ConclusionNSO, by improving the antioxidant status and energy metabolism, could significantly alter the ability of the intestine to protect against free radical-mediated arsenic toxicity in intestine. Thus, NSO may have an excellent scope in managing gastrointestinal distress in arsenic intoxication.     

湖南省长柄茧蜂属两新种：膜翅目：茧蜂科：优茧蜂亚科

本文记述分布湖南省城步县的长柄茧蜂属Ｓｔｒｅｂｌｏｃｅｒａ两新种,赵氏长柄茧蜂Ｓｔｒｅｂｌｏｃｅｒａ ｃｈａｏｉ Ｙｏｕ ｅｔ Ｚｈｏｕ,ｓｐ．ｎｏｖ．,何氏长柄茧蜂Ｓｔｒｅｎｌｏｃｅｒａ ｈｅｉ Ｙｏｕ ｅｔ Ｘｉａｏ,ｓｐ．ｎｏｖ．,模式标本存于湖南农学院。     

菌株YN145对稻瘟病菌黑色素合成的影响及全基因组分析

【背景】枯草芽孢杆菌YN145是一株从湖南省桃江县的健康稻株中分离的细菌,前期研究中该菌对稻瘟病菌拮抗效果显著,在生物防治方面有很大的应用潜力。【目的】深入研究该菌株的生防机制并挖掘次级代谢产物基因资源。【方法】在4株稻瘟病菌生防菌中,选择其胞外抗菌物质抑制稻瘟病菌黑色素合成效果最佳的菌株YN145,采用紫外-可见分光光度计在波长400 nm处测定胞外和菌丝体内黑色素液的吸光度值,采用菌丝生长抑制平板法和分生孢子萌发抑制法测定抑菌活性。采用PacBio第三代测序和IlluminaHiSeq第二代测序相结合的技术对菌株YN145进行全基因组测序,并对测序数据进行组装,注释预测基因的功能,分析次级代谢产物合成基因簇。【结果】菌株YN145的胞外抗菌物质能较好地抑制稻瘟病菌黑色素合成、分生孢子萌发和菌丝生长。菌株YN145全基因组大小为4 167 871 bp,GC含量为43.86%,编码序列(coding sequence, CDS)数量为4 294个;共找到85个tRNA、30个rRNA和92个sRNA。同时预测到5个已知的次级代谢产物合成基因簇,分别编码合成bacillaene、bac...     

PlantACT! – how to tackle the climate crisis

Greenhouse gas (GHG) emissions have created a global climate crisis which requires immediate interventions to mitigate the negative effects on all aspects of life on this planet. As current agriculture and land use contributes up to 25% of total GHG emissions, plant scientists take center stage in finding possible solutions for a transition to sustainable agriculture and land use. In this article, the PlantACT! (Plants for climate ACTion!) initiative of plant scientists lays out a road map of how and in which areas plant scientists can contribute to finding immediate, mid-term, and long-term solutions, and what changes are necessary to implement these solutions at the personal, institutional, and funding levels.     

葫芦科蔬菜花粉萌发特性的研究

试验采用花粉离体萌发技术,对葫芦科７属８种蔬菜花粉生活力进行了较为深入的研究,结果表明：葫芦科蔬菜花粉属于“嗜硼、好气、喜温、较耐储藏”的类型。适量的蔗糖可以提高萌发率,并明显有利于花粉管生长。此外,试验中还发现不同种作物花粉萌发力的差异与花粉萌发孔或沟的特征有明显关系联系。     

湖南省节甲茧蜂属二新种(膜翅目:茧蜂科, 甲腹茧蜂亚科)

本文报道湖南省节甲茧蜂属 Sigalphus Latreille,1802两新种。节甲茧蜂属隶茧蜂科,甲腹茧蜂亚科 Chloninae(Shenefelt,1973),该属在我国为首次记录。主要特征是头横置,下颚须4节;胸部粗壮,不宽于头,中胸盾片盾纵沟深;前翅肘室3个,径脉终止在翅尖端之前,第2肘室矩形,肘脉自基脉伸出,迥脉前叉式,小脉后叉式,前翅臀叶基部具横脉,后翅径室横脉弱;腹部长于头胸之和,3节,第1、2节背板之间能活动,第3背板侧缘后方有2齿状突;产卵管短。该属已知7种,分布在新北区(美国)1种、非洲区(马达加     

Preparation and molecular characterization of a polyclonal antibody as an efficient cutworm reference protein

Antibodies, which are wildly used in molecular researches, are proteins secreted by plasma cells that can specifically recognize specific antigens. To obtain a stable reference antibodies are important for protein analysis. In this study, a capable glyceraldehyde phosphate dehydrogenase (GAPDH) antiserum against most noctuid larval protein samples was prepared. Firstly, the full-length gapdh was amplified from Spodoptera exigua larvae to construct the prokaryotic expression vector. The purified His-tag fused GAPDH protein was used to immunize rabbits for the antiserum preparation. Protein samples extracted from 11 insect species distributed across seven families and three orders were used to perform the Western bolt analysis. The bright specific bands were detected in S. exigua, S. litura, Helicoverpa armigera, and Mythimna seperata protein samples, indicating that this antiserum may be capable of detecting noctuid larval encoded GAPDH. Further immunofluorescence identification of H. armigera and S. exigua paraffin section slides with GAPDH antiserum exhibited an identical cyto-stained image. The GAPDH antiserum prepared in this study is useful and efficient as reference antibodies in studies involving noctuid larval protein samples in other related fields.     

香艳梨离体培养研究

本试验以香艳梨的茎尖,不带芽茎段,带芽茎段,叶片,叶柄为试材,以１／２ＭＳ为基本培养基,分别附加０．５～２．０ｍｇ／Ｌ的６－卡基氨基嘌呤（６－ＢＡ）和０．１ｍｇ／Ｌ的萘乙酸（ＮＡＡ）、吲哚乙酸（ＩＡＡ）,２,４－二氯苯氧乙酸（２,４－Ｄ）进行离体培养研究。结果表明,试材用０．１％ＨｇＣｌ２灭菌５～６分钟为宜;在７月份接种感染率低,愈伤组织形成较快;茎尖,不带芽茎段,带芽茎段,叶片均可作为离体培养的外植体,叶片的脱分化,分化的效果尤为明显,叶柄不宜作外植体;１／２ＭＳ＋１．５ｍｇ·Ｌ－１６－ＢＡ＋０．１ｍｇ·Ｌ－１ＮＡＡ有利于脱分化;１／２ＭＳ＋１．０ｍｇ·Ｌ－１６－ＢＡ有利于分化;瓶外生根优于瓶内生根。本试验可为香艳梨的工厂化育苗提供参考。     

The role of plants in the removal of nutrients at a constructed wetland treating agricultural (dairy) wastewater,Ontario, Canada

The South Nation River Watershed, in eastern Ontario, Canada, is an agricultural watershed impacted by excess nutrient loading primarily from agricultural activities. A constructed wetland for the treatment of agricultural wastewater from a 150-cow dairy operation in this watershed was monitored in its eighth operating season to evaluate the proportion of total nitrogen (TN) (approximated by total Kjeldahl nitrogen (TKN) due to low NO₃⁻) and total phosphorus (TP) removal that could be attributed to storage in Typha latifolia L. and Typha angustifolia L., which dominate this system. Nutrient loading rates were high, with 16.2 kg ha⁻¹ d⁻¹ N and 3.4 kg ha⁻¹ d⁻¹ P entering the wetland and loading the first wetland cell. Plant uptake accounted for 0.7% of TKN removal when the vegetated free water surface cells were considered together. However, separately, in the second wetland cell with lower N and P loading rates, plants accounted for 9% of TKN, 21% of NH₄⁺ and 5% of TP removal. Plant uptake was significant to overall removal given wetland age and nutrient loading. Nutrient storage during the growing season at this constructed wetland helped reduce the nutrient load entering the watershed, already stressed by intensive local agriculture.     

Role of iron plaque in Cd uptake by and translocation within rice (Oryza sativa L.) seedlings grown in solution culture

A hydroponics culture experiment was conducted to investigate the effect of iron plaque on Cd uptake by and translocation within rice seedlings grown under controlled growth chamber conditions. Rice seedlings were pre-cultivated for 43 days and then transferred to nutrient solution containing six levels of Fe (0, 10, 30, 50, 80 and 100 mg L⁻¹) for 6 days to induce different amounts of iron plaque on the root surfaces. Seedlings were then exposed to solution containing three levels of Cd (0, 0.1 and 1.0 mg L⁻¹) for 4 days. In order to differentiate the uptake capability of Cd by roots with or without iron plaque, root tips (white root part without iron plaque) and middle root parts (with iron plaque) of pre-cultivated seedlings treated with 0, 30 and 50 mg L⁻¹ Fe were exposed to ¹⁰⁹Cd for 24 h. Reddish iron plaque gradually became visible on the surface of rice roots but the visual symptoms of the iron plaque on the roots differed among treatments. In general, the reddish color of the iron plaque became darker with increasing Fe supply, and the iron plaque was more homogeneously distributed all along the roots. The Fe concentrations increased significantly with increasing Fe supply regardless of Cd additions. The Cd concentrations in dithionite–citrate–bicarbonate (DCB)-extracts and in shoots and roots were significantly affected by Cd and Fe supply in the nutrient solution. The Cd concentrations increased significantly with increasing Cd supply in the solution and were undetectable when no Cd was added. The Cd concentrations in DCB-extracts with Fe supplied tended to be higher than that at Fe₀ at Cd_0.1, and at Cd_1.0, DCB-Cd with Fe supplied was significantly lower. Cd concentrations in roots and shoots decreased with increasing Fe supply at both Cd additions. The proportion of Cd in DCB-extracts was significantly lower than in roots or shoots. Compared to the control seedlings without Fe supply, the radioactivity of ¹⁰⁹Cd in shoots of seedlings treated with Fe decreased when root tips were exposed to ¹⁰⁹Cd and did not change significantly when middle parts of roots were exposed. Our results suggest that root tissue rather than iron plaque on the root surface is a barrier to Cd uptake and translocation within rice plants, and the uptake and translocation of Cd appear to be related to Fe nutritional levels in the plants.