Haemolytic activity in different species of the genus Prymnesium (Haptophyta)

Author(s):  
S. Seoane ◽  
P. Riobó ◽  
J. Franco

The genus Prymnesium includes several species that produce toxins with cytotoxic, ichthyotoxic, neurotoxic and haemolytic activity. Bloom episodes of Prymnesium species have been reported from several parts of the world (North America, Europe, Africa, Asia and Australia), especially from temperate and subtropical regions and most of them from brackish waters. Blooms cause great economic losses to aquaculture and fisheries around the world. The ichthyotoxic and allelopathic effects of Prymnesium have been linked to the presence of Haemolysin 1, Prymnesins 1 and 2 and, more recently, fatty acids and fatty acid amides. The toxicology of this genus with regard to different growth conditions such as light, nutrients and other parameters has been well documented. It is unknown, however, whether different species and strains from the Prymnesium genus all produce the same types and level of toxins. In this study, we have determined the haemolytic activity of eight different strains from the genus Prymnesium in both exponential and stationary phases of growth. We have also evaluated the efficiency of the extraction solvent.

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 241
Author(s):  
Joon Moh Park ◽  
Jachoon Koo ◽  
Se Won Kang ◽  
Sung Hee Jo ◽  
Jeong Mee Park

Rhodococcus fascians is an important pathogen that infects various herbaceous perennials and reduces their economic value. In this study, we examined R. fascians isolates carrying a virulence gene from symptomatic lily plants grown in South Korea. Phylogenetic analysis using the nucleotide sequences of 16S rRNA, vicA, and fasD led to the classification of the isolates into four different strains of R. fascians. Inoculation of Nicotiana benthamiana with these isolates slowed root growth and resulted in symptoms of leafy gall. These findings elucidate the diversification of domestic pathogenic R. fascians and may lead to an accurate causal diagnosis to help reduce economic losses in the bulb market.


Author(s):  
Michael Halim

The Coronavirus pandemic has caused negative effects across the globe; mortality and morbidity being the main impact. After WHO, termed the disease a pandemic in March 2020, they gave in health guidelines to follow to control the spread of the disease. The health industry, academia, and different governments are united to develop and test various vaccines at an unprecedented speed to combat the pandemic fully and bring the world back to its feet. Some of the vaccines developed include Pfizer, Moderna, and AstraZeneca. However, just like other viruses, the SAR-CoV-2 virus keeps changing through mutation, as various variants, different from the first one are emerging. Evidence shows that the three new variants; UK, Brazil, and South Africa are more severe in terms of transmissibility, disease severity, evading of the immune response, and reducing the ability to neutralized antibodies, compared to the original coronavirus. With such knowledge of the existence of different strains, the arises concerns on whether the already available vaccines are effective enough in preventing the new COVID-19 strains. Studies are still underdeveloped to learn more on the virologic, epidemiologic, and clinical characteristics of the ever-emerging variants. This research, through a systemic review of literature, seeks to find out whether the variants of SAR-CoV-2 have an impact on the efficacy of various vaccines developed in fighting the disease and the entire body’s immune response.


2021 ◽  
Vol 03 (01) ◽  
pp. 191-196
Author(s):  
Durdona Alisher Qizi Yuldashova ◽  
Keyword(s):  

Covid-19 has revolutionized the economy around the world, including in Uzbekistan. The panic that followed the virus has led to even greater economic losses. In the following thesis, you will learn about employment, unemployment and income changes in Uzbekistan


2018 ◽  
pp. 31-33
Author(s):  
G. S. Martirosyan

At present it is very actual in vegetable growing the development of highly effective and ecologically safe methods for increasing yields and plant resistance to unfavorable growth conditions. One of these methods is grafting. The goal of the study was to learn the influence of the rootstock on the characteristics of the growth, development and yield of cucumber. Research was conducted in 2015-2016 in greenhouse in spring-summer period in Armenia. As a scions was used cucumber variety Nazrvan, which was grafted on 5 pumpkin rootstocks (VI033637, VI03338, VI03364, VI040903, VI056328) from the collection of the World Vegetable Center (WVC). The grafting was carried out according to the standard method. When the VI033637 rootstock was used, flowering started 5 days earlier than the ungrafted plants, while when grafted on VI040903, the fruits ripened 6.2 days earlier. High increase of early yield (33.3%) received when used both above mentioned rootstocks. VI033638 – 4.1 kg/m2 and VI033664- 9.9 kg/m2 samples provided high increase of the total yield. For all the types of rootstocks the grafted plants of cucumber surpass the non-grafted ones by height from 4.7 % to 21.7%, by marketability of fruits from 5% to 14% and by fruit mass from 15 gr to 45 g. At the beginning of fruit-setting of cucumber plants the number of female flowers increased from 27% to 63% depending on the rootstock sample. The amount of dry substances in all grafted plants has increased by 4.4-8.8% and the amount of vitamin C by 1.8-9.2%. As a result of research carried out by us, perspective rootstocks (VIO33638 and VIO33664) are identified by a set of economically valuable characteristics which are recommended for applying in the further investigation and breeding activities and in production of grafted plants.


2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Mengya Cao

In recent years, the financial crisis has affected the economies of all countries in the world. At that time, it seriously restricted the development of the world economy. From a modern perspective, the difficult period of the world economic crisis caused by the financial crisis has passed, but the negative impact of the economic crisis can not be eliminated in a short time. Dispersed, the crisis has brought both opportunities and challenges to the country as well as heavy economic losses. Under the background of economic globalization, only by making a scientific and effective analysis of the world economic situation and keeping up with the trend of the world economy, can we effectively promote the domestic economic development and industrial structure, and enable our economy to develop healthily and substantially.


1985 ◽  
Vol 7 (6) ◽  
pp. 169-175
Author(s):  
George A. Nankervis

The role of cytomegalovirus in human disease is a still-evolving story. Hanshaw presented an excellent review article on the subject in 1981 in this publication; this current review is an update, with particular emphasis on new concepts in the epidemiology and prevention of cytomegaloviral infection and disease. Historically, evidence of infection with cytomegalovirus was first reported by pathologists in many parts of the world. They noted the presence of giant cells with intranuclear inclusions while examining a diversity of organs microscopically. Isolation of the virus and development of serologic techniques eventually enabled a definitive study of the agent, its pathogenesis and epidemiology. Biologically, it is one of the herpesviruses and, as such, is a DNA virus. Other members of the group include varicella-zoster, herpes simplex, and Epstein-Barr virus. Several different strains of cytomegalovirus exist, and they have specific characteristics which are of interest. The virus is cell associated and tends to be very labile; it has a tendency to become latent and may possibly have malignant potential. EPIDEMIOLOGY Prevalence Infection with cytomegalovirus is found throughout the world. Studies of prevalence in a number of diverse populations have indicated that cytomegaloviral infection is ubiquitous. The major differences in prevalence between populations are related to the speed of acquisition of infection in various geographic and socioeconomic settings.


Author(s):  
Yu Cao ◽  
Katherine Dever ◽  
Sathesh Kumar Sivasankaran ◽  
Scott V. Nguyen ◽  
Guerrino Macori ◽  
...  

Cronobacter sakazakii is a typical example of a xerotolerant bacterium. It is epidemiologically linked to low moisture foods like powdered infant formula (PIF) and is associated with high fatality rates among neonates. We characterized the xerotolerance in a clinically isolated strain, C. sakazakii ATCC™29544 T , and compared the desiccation tolerance with an environmental strain, C. sakazakii SP291, whose desiccation tolerance was previously characterized. We found that, although the clinical strain was desiccation-tolerant, the level of tolerance was compromised when compared to the environmental strain. RNA-seq based deep transcriptomic characterization identified a unique transcriptional profile in the clinical strain compared to what was already known for the environmental strain. As RNA-seq was also carried out in different TSB growth conditions, genes that were expressed specifically under desiccated conditions were identified and denoted as desiccation responsive genes (DRGs). Interestingly, these DRGs included transcriptomic factors like fnr , ramA, and genes associated with inositol metabolism, a phenotype as yet unreported in C. sakazakii . Further, the clinical strain did not express the proP gene, which was previously reported to be very important for desiccation survival and persistence. Interestingly, analysis of the plasmid genes showed that the iron metabolism in desiccated C. sakazakii ATCC™29544 T cells specifically involved the siderophore cronobactin encoded by the iucABCD genes. Confirmatory studies using qRT-PCR determined that, though the secondary desiccation response genes were upregulated in C. sakazakii ATCC™29544 T , the level of up-regulation was lower compared to that in C. sakazakii SP291. All these factors could collectively contribute to the compromised desiccation tolerance in the clinical strain. IMPORTANCE Cronobacter sakazakii has in past led to outbreaks, particularly associated with food that are low in moisture content. This species has adapted to survive in low water conditions and can survive in such environments for long periods. These characteristics have enabled the pathogen to contaminate powder infant formula, a food matrix with which the pathogen has been epidemiologically associated. Even though clinically adapted strains can also be isolated, there is no information on how the clinical strains adapt to low moisture environments. Our research assessed the adaptation of a clinically isolated strain to low moisture survival on sterile stainless steel coupons and compared the survival to a highly desiccation-tolerant environmental strain. We found that, even though the clinical strain is desiccation-tolerant, the rate of tolerance was compromised compared to the environmental strain. A deeper investigation using RNA-seq identified that the clinical strain used pathways different from that of the environmental strain to adapt to low moisture conditions. This shows that the adaptation to desiccation conditions, at least for C. sakazakii , is strain-specific and that different strains have used different evolutionary strategies for adaptation.


Author(s):  
Anitha Ruth J. ◽  
Uma R. ◽  
Meenakshi A.

Apples are the most productive fruits in the world with a lot of medicinal and nutritional value. Significant economic losses occur frequently due to various diseases that occur on a huge scale of apple production. Consequently, the effective and timely discovery of apple leaf infection becomes compulsory. The proposed work uses optimal deep neural network for effectively identifying the diseases of apple trees. This work utilizes a convolution neural network to capture the features of Apple leaves. Extracted features are optimized with the help of the optimization algorithm. The optimized features are utilized in the leaf disease identification process. Here the traditional DNN algorithm is modified by means of weight optimization using adaptive monarch butterfly optimization (AMBO) algorithm. The experimental results show that the proposed disease identification methodology based on the optimized deep neural network accomplishes an overall accuracy of 98.42%.


Plant Disease ◽  
2013 ◽  
Vol 97 (9) ◽  
pp. 1175-1180 ◽  
Author(s):  
Carl A. Strausbaugh ◽  
Imad A. Eujayl ◽  
Leonard W. Panella

Rhizoctonia crown and root rot caused by Rhizoctonia solani can cause serious economic losses in sugar beet fields. Preliminary evidence suggests that there could be interactions between different strains and resistance sources. Thus, field studies were conducted to determine whether nine R. solani AG-2-2 IIIB strains varied for virulence when compared with a noninoculated check and interacted with five sugar beet lines (four resistant lines and a susceptible check). The studies were arranged in a randomized complete block design with six replications. Roots were evaluated for surface rot and internal fungal and bacterial rot in September. All strains were virulent on the susceptible check, FC901/C817, and had a similar ranking (r = 0.80 to 0.97; P = 0.0096 to <0.0001) regardless of disease variable. Line FC709-2 was resistant (response not different from noninoculated check, P ≥ 0.1042) to all strains, while the strain responses resulted in weak interactions with less-resistant lines in 14 of 19 variable-year combinations. Because most commercial sugar beet cultivars contain low to intermediate resistance to Rhizoctonia crown and root rot, the strain used to screen should be considered in order to maintain consistent responses between nurseries and commercial fields.


Author(s):  
Gerhard Berz

Windstorm disasters (including storm surges) account for about one-third of all natural disasters throughout the world (by number, fatalities and economic losses), but for more than two-thirds of the corresponding insured losses. Trend analyses reveal that major windstorm disasters and the losses generated by them have increased drastically in recent decades. Risk partnership between the state, the affected population and the insurance industry assumes a key role with regard to the windstorm hazard. Scientists, engineers and insurers must work together in formulating their requirements and shaping them in such a way that politicians can derive clearly recognizable policy options (e.g. land-use, restrictions, design-code adjustments) from them. Another important aspect is stepping up the efforts being made towards curbing climate change, which will, otherwise, exacerbate the risk in the future.


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