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101.
Roberta Teta Germana Esposito Karishma Kundu Mariano Stornaiuolo Silvia Scarpato Antonino Pollio Valeria Costantino 《Marine drugs》2022,20(4)
In this study, a strain of Anabaena flos-aquae UTEX 1444 was cultivated in six different concentrations of iron (III). Cultures were extracted with organic solvents and analyzed using our dereplication strategy, based on the combined use of high-resolution tandem mass spectrometry and molecular networking. The analysis showed the presence of the siderophores’ family, named synechobactins, only in the zero iron (III) treatment culture. Seven unknown synechobactin variants were present in the extract, and their structures have been determined by a careful HRMS/MS analysis. This study unveils the capability of Anabaena flos-aquae UTEX 1444 to produce a large array of siderophores and may be a suitable model organism for a sustainable scale-up exploitation of such bioactive molecules, for the bioremediation of contaminated ecosystems, as well as in drug discovery. 相似文献
102.
L Hesselink SS Orlov A Liu A Akella D Lande RR Neurgaonkar 《Science (New York, N.Y.)》1998,282(5391):1089-1094
Optically gated recording and nonvolatile readout in a digital volume holographic data storage system that uses a pair of mutually incoherent light sources during recording and only one for readout were demonstrated recently. This approach used stoichiometric lithium niobate, which after post-growth processing gave rise to an at least two orders of magnitude improvement in sensitivity over the best materials reported previously. It is also shown that by adding certain dopants (iron and manganese) to near-stoichiometric lithium niobate, the dark storage time and gating efficiency can be increased compared with previous work. The underlying physical mechanisms of gated recording and the effectiveness of the gating process responsible for this manifold improved performance are discussed, and bipolarons and small polarons are identified as the responsible photorefractive species. 相似文献
103.
Laboratory studies show that the reaction of short-lived O2(B3Sigmau) molecules (lifetime approximately 10 picoseconds) with N2 and the photodissociation of the N2:O2 dimer produce NOx in the stratosphere at a rate comparable to the oxidation of N2O by O(1D). This finding implies the existence of unidentified NOX sinks in the stratosphere. The NO2 observed in this experiment is isotopically heavy with a large 15N/14N enhancement. However, photodissociation of this NO2 unexpectedly produced NO molecules with a low 15N/14N ratio. The diurnal odd-nitrogen cycle in the stratosphere will be marked by a complex isotope signature that will be imprinted on the halogen and HOX catalytic cycles. 相似文献
104.
105.
Ranabir Sahu Narayanasamy Prabhakaran Pritha Kundu Aundy Kumar 《Plant pathology》2021,70(6):1409-1420
Stem rust caused by Puccinia graminis f. sp. tritici is one of the most devastating diseases of wheat. Breakdown of host resistance under field conditions triggered by the evolution of new pathogenic races and pathotypes is a perennial threat for wheat cultivation. Rice, often grown in a rice–wheat cropping system, is immune to rust infection. Our microscopic studies revealed that P. graminis f. sp. tritici, although displaying nearly identical uredospore germination, stomatal entry, and epi- and endophytic mycelial growth in rice and wheat, failed to sporulate to cause rust disease in rice. We identified 18 key defence signalling genes in rice and unravelled their elicitation dynamics in time-course studies during infection. ICS1, NPR1-3, PRs, EDS1, PAD4, FMO1 (salicylic acid [SA] signalling), and ethylene-related genes (ACO4 and ACS6) were strongly elicited in rice. However, genes from the jasmonic acid (JA) signalling pathway (LOX2, AOS2, MYC2, PDF2.2, JAZ8, JAZ10) showed a delayed response during colonization in rice compared to an early or no induction in wheat. However, the JA/ethylene marker gene PDF2.2 was strongly induced in wheat as early as 12 hr postinoculation. Furthermore, rice and wheat displayed specific profiles of accumulation of various phenolic acids during P. graminis f. sp. tritici 40A infection. We propose a model where a differential modulation of the SA/JA-dependent defence network may modulate nonhost resistance. A deeper understanding of the molecular mechanism governing differential elicitation of defence signalling may provide a novel resistance mechanism for the sustainable management of rust diseases. 相似文献
106.
Munnurpal Satyanarayana Mahesh Madhu Mohini Pankaj Jha Sanjay Pandurang Sawant Shivlal Singh Kundu Ramesh Chander Kuhad 《Tropical animal health and production》2013,45(8):1817-1823
Wheat straw was subjected to solid-state fermentation (SSF) with lignolytic white-rot fungus (WRF) Crinipellis sp. for 5 days to improve the nutritive value and digestibility. The fungal treatment caused a significant (P?<?0.05) decrease in cell wall constituents viz., neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose, lignin, and cellulose to the extent of 10.4, 11.2, 8.7, 8.7, and 12.1 %, respectively, with increase (P?<?0.05) in crude protein (CP) (51.6%) and ash (25.8%) contents in fungal treated wheat straw (FT-WS) than untreated wheat straw (UT-WS). Further, in vitro gas production, in vitro true dry matter digestibility and in vitro true organic matter digestibility at 48 h, metabolizable energy (ME) content, microbial biomass production, and short-chain fatty acids synthesis were significantly (P?<?0.05) higher in FT-WS. In vivo feeding trial in 10 Sahiwal calves (8–12 months) comprised of (1) control group (T1) fed with ad libitum chopped UT-WS and (2) treatment group (T2) offered with ad libitum chopped FT-WS, in addition to supplementation of groundnut cake and green berseem (Trifolium alexandrium) forage to both groups. Digestibility of nutrients for dry matter (DM), organic matter, CP, NDF, ADF, hemicellulose, cellulose, and total carbohydrates were significantly (P?<?0.05) higher in T2 compared to T1. Moreover, daily DM (P?<?0.05), digestible crude protein (P?<?0.01), and ME intakes were also higher (P?<?0.05) in group T2 with higher (P?<?0.05) nitrogen (N) retention, which resulted in significantly (P?<?0.05) higher average daily gain in body weight (135 vs. 102 g/day). It was concluded that SSF with WRF Crinipellis sp. holds potential in upgrading the nutritional worth of wheat straw for feeding growing calves. 相似文献
107.
Prem Sagar Maurya Radhamma Lakshmipathy Rakesh Balaraju Pradeep Saroj Kumar Krishnendu Kundu Rajat Garg Hira Ram Ashok Kumar Partha Sarathi Banerjee 《Tropical animal health and production》2013,45(4):941-946
A total of 938 faecal samples (461 cattle calves, 264 buffalo calves, 55 lambs, 116 kids and 42 piglets) from different livestock farms and individual small holdings in six targeted states of India were collected and screened by modified Ziehl–Neelsen staining technique to determine the prevalence of Cryptosporidium spp. and its association with age, sex, season and faecal consistency in domesticated animals. Overall, 16.2 % of the animals were positive for Cryptosporidium infection with prevalence of 16.3, 24.2, 1.8, 3.5 and 19.1 % in cattle calves, buffalo calves, lambs, kids and piglets, respectively. The prevalence of infection was significantly higher (p?<?0.05) in bovines (19.3 % cattle and 33.7 % buffalo) below 1 month of age than in animals between 1 and 3 months of age. But in piglets, it was higher in the age group of 1 to 3 months (22.6 %) than in younger animals (9.1 %). Also, higher prevalence (p?>?0.05) was recorded in females than in males. Seasons had a significant effect (p?<?0.05) on the prevalence of infection in large ruminants, with the highest prevalence in monsoon (cattle 28.8 % and buffalo 36.6 %) followed by pre-monsoon and post-monsoon season. However, in case of sheep and goats, the prevalence was higher (p?>?0.05) in post-monsoon than in monsoon season. A high degree of association was noticed between Cryptosporidium infection and diarrhoea in ruminants screened during the present study. But, in case of pigs, the prevalence was higher in non-diarrhoeic than in diarrhoeic animals. Genotyping of Cryptosporidium spp. based on nested PCR amplification of partial 18S rRNA and its subsequent digestion with SspI, VspI and MboII restriction enzymes revealed prevalence of Cryptosporidium parvum in representative number of positive samples of cattle, buffalo and goats. 相似文献
108.
SR Isberg JL Moran R De Araujo N Elliott SS Davis L Melville 《Australian veterinary journal》2019,97(10):390-393
Recently, the Kunjin strain of West Nile virus (WNVKUN) has been detected using qRT‐PCR in belly skin lesions of farmed juvenile saltwater crocodiles. This follows an established association between similar lesions and West Nile virus in American alligators. The lesions present as cutaneous lymphohistiocytic aggregates in the dermal layers of both species. While these lesion do not create an obvious defect on the live crocodile, upon tanning the lesion area collapses and does not uptake the dye evenly, thus reducing its aesthetic appeal. As a result, skins are being rejected jeopardising the economic viability of the Australian crocodile industry. Over 50 skin lesions have since been confirmed as WNVKUN‐positive and preliminary evidence of lesion restructuring is presented. Horizontal transmission of WNVKUN by mosquitoes is well‐established but other transmission routes, such as ingestion and cloacal shedding, need further evaluation. An infection trial is currently underway to ensure WNVKUN is the causative agent of these skin lesions. 相似文献
109.
110.
This study was exclusively conducted to evaluate healing of surgically created defects on the radius of adult Black Bengal goat after implantation of porous bioglass blocks and compare the process kinetics with normal healing. Twelve Black Bengal goats were divided randomly into two groups: control and experimental group implanted with bioglass blocks. Unicortical bone defects in radius were generated in all animals under aseptic condition. Local inflammatory reaction and healing of wound, radiological investigations, histological studies, oxytetracycline leveling and angiographic studies were performed up to 90th day post-operatively and compared with normal healing. It has been found that extensive new bone formation originating from host bone towards the implant whereas in control, the process was active from both the ends; the defect site appeared as homogenous nonfluorescent area. Thus, porous bioglass promoted bone formation over the entire extension of the defect independent of size of block in comparison to control group. 相似文献