Ultrastructural characterisation of the host–pathogen interface in white blister-infected Arabidopsis leaves

In this study transmission electron microscopy (TEM) was used to examine details of the host–pathogen interface in Arabidopsis thaliana cotyledons infected by Albugo candida, causal agent of white blister. After successful entry through stomatal pores, the pathogen developed a substomatal vesicle and subsequently produced intercellular hyphae. TEM observations revealed that coenocytic intercellular hyphae ramified and spread intercellularly throughout the host tissue forming several haustoria in host mesophyll cells. Intracellular haustoria were spherical and 4.5 μm in diameter. Each haustorium was connected to intercellular hyphae by a narrow, slender haustorium neck. The cytoplasm of the haustorium included the organelles characteristic of the pathogen. No obvious response was observed in host cells following formation of haustoria. Most of the mesophyll cells contained normal haustoria and the host cytoplasm displayed a high degree of structural integrity. Absence of host cell wall alteration and cell death in penetrated host cells suggest that the pathogen exerts considerable control over basic cellular processes and in this respect, response to this biotrophic Oomycete differs considerably from responses to other pathogens such as necrotrophs. Modification of the host plasma membrane (PM) along the cell wall and around the haustoria, was detected by applying the periodic acid-chromic acid-phosphotungstic acid (PACP) staining technique. After staining with PACP, the host PM was found to be intensely electron dense where it was adjacent to the host cell wall and the distal region of the haustorial neck. By contrast, the extrahaustorial membrane, where the host PM surrounded the haustorium, was consistently very lightly stained.     

TOP1 inhibition therapy protects against SARS-CoV-2-induced lethal inflammation

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Genetic polymorphism of beta-lactoglobulin gene in native Turkish sheep breeds

The genetic polymorphism of the beta-lactoglobulin gene was investigated in three native Turkish sheep breeds. The study was carried out on 108 sheep (29 Kivircik, 38 G?k?eada, and 41 Sakiz) by means of PCR-RFLP methods. Two genetic variants (A and B) and three genotypes (AA, AB, and BB) of beta-lactoglobulin have been identified. The gene frequencies of beta-LG A and B were 0.7759 and 0.2241 in Kivircik, 0.7632 and 0.2368 in G?k?eada, and 0.9756 and 0.0244 in Sakiz breeds, respectively. The populations were in Hardy-Weinberg equilibrium in all samples from the three breeds.     

Escherichia coli lipopolysaccharides produce serotype-specific hypothermic response in biotelemetered rats

We investigated whether LPS-induced hypothermia develops in a serotype-specific manner in biotelemetered conscious rats. Two different Escherichia coli serotypes of LPSs were injected at a dose of 250 mug/kg ip. E. coli O55:B5 LPS elicited an initial hypothermia and subsequent fever, but E. coli O111:B4 LPS caused more potent monophasic hypothermia. Serum tumor necrosis factor (TNF)-alpha levels were dramatically elevated at the initial phase of the hypothermia induced by both LPSs. This elevation tended to subside at the nadir of E. coli O55:B5 LPS-induced response but progressively increased at the nadir of E. coli O111:B4 LPS hypothermia. Serum IL-10 levels were moderately elevated at the initial phase of the hypothermia and persisted at the same level at the nadir of each LPS-induced response. No change was observed at the serum IL-18 levels. A selective cyclooxygenase (COX)-1 enzyme inhibitor, valeryl salicylate (20 mg/kg sc), abolished the hypothermia without any effect on the elevated cytokine levels. Another COX-1-selective inhibitor, 5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-(trifluoromethyl)-1H-pyrazole (SC-560; 1 mg/kg sc) inhibited hypothermic responses as well. Meanwhile, cytokine levels were also reduced by SC-560 treatment. These findings suggest that LPS-induced hypothermia may have serotype-specific characteristics in rats. E. coli O111:B4 LPS has more potent hypothermic activity than E. coli O55:B5 LPS; that may presumably be related to its higher or sustained capability to release antipyretic cytokines, such as TNF-alpha. COX-1 enzyme may be involved in the generation of the hypothermia, regardless of the type of LPS administered.     

Genomic analysis to screen potential genes and mutations in children with non-syndromic early onset severe obesity: a multicentre study in Turkey

Molecular Biology Reports - Obesity is a complex genetic-based pediatric disorder which triggers life-threatening conditions. Therefore, the understanding the molecular mechanisms of obesity has...     

Genetic Polymorphism of β-Lactoglobulin Gene in Native Turkish Sheep Breeds

The genetic polymorphism of the β-lactoglobulin gene was investigated in three native Turkish sheep breeds. The study was carried out on 108 sheep (29 Kıvırcık, 38 G?k?eada, and 41 Sakız) by means of PCR-RFLP methods. Two genetic variants (A and B) and three genotypes (AA, AB, and BB) of β-lactoglobulin have been identified. The gene frequencies of β-LG A and B were 0.7759 and 0.2241 in Kıvırcık, 0.7632 and 0.2368 in G?k?eada, and 0.9756 and 0.0244 in Sakız breeds, respectively. The populations were in Hardy–Weinberg equilibrium in all samples from the three breeds.     

Quantification the relationship between FITA scores and EMG skill indexes in archery.

Forearm electromyographic (EMG) data are assumed to be an effective method in estimating performance level in archery. The aim of the current study was to establish archery skill indexes based on EMG data. Elite (n=7, FITA score=1303.4+/-26.2), beginner (n=6, FITA score=1152+/-9.0) and non-archers (n=10, assumed FITA score=250+/-0), were involved in the study. EMG activity of Muscle flexor digitorum superficialis and Muscle extensor digitorum were quantified. Two-second periods--1 s before and 1 s after the fall of the clicker--were used to obtain averaged and rectified EMG data. The averaged and rectified EMG data were filtered by averaging finite impulse response filter with 40 ms time window and then normalized with respect to maximum voluntary contraction. To estimate FITA scores from EMG data, the following skill indexes that based on mean area under some parts of processed EMG waveforms was offered for archery. These were the pre-clicker archery skill index (PreCASI), post-clicker archery skill index (PostCASI), archery skill index (ASI) and post-clicker archery skill index 2 (PostCASI2).The correlations between rank of FITA scores and natural logarithms of archery skill indexes were significant for log(PreCASI): r=-0.66, p<0.0008; for log(PostCASI): r=-0.70, p<0.0003; for log(ASI): r=-0.74, p<0.0001; log(PostCASI2): r=-0.63, p<0.002. It is concluded that EMG skill indexes may be useful for: (a) assessing shooting techniques, (b) evaluation of archers' progress and (c) selection of talented archers.