The water-hyacinth grasshopper, Cornops aquaticum, occurs in freshwater environments in the New World between latitudes 23°N and 35°S. At the southernmost margin of this distribution the populations are polymorphic for three centric fusions (Robertsonian translocations). The frequencies of these chromosome rearrangements increase southwards and the recombination in structural homozygotes and heterozygotes diminishes both along the middle and lower courses of the Paraná River. In the present paper we report a similar cline along the southward flowing Uruguay River. In addition, we report the morphological effects of two of these centric fusion polymorphisms, namely the fusions between chromosomes 2 and 5 of the standard complement (fusion 2/5) and chromosomes 3 and 4 (fusion 3/4) and extend this study to the Uruguay River. There is a strong inverse correlation of fusion frequency with temperature, which indicates that these polymorphisms may be related to increased tolerance of colder climates in this originally tropical species, or some other correlated variable. This study is a further example of chromosomal clines correlated with latitude and is one of a few examples of chromosome polymorphisms associated with phenotypic effects. Finally, it indicates ways of using this species for controlling pests., Pablo C. Colombo, María I. Remis., and Obsahuje bibliografii
Phosphene is the experience of light without natural visual stimulation. It can be induced by electrical stimulation of the retina, optic nerve or cortex. Induction of phosphenes can be potentially used in assistive devices for the blind. Analysis of phosphene might be beneficial for practical reasons such as adjustment of transcranial alternating current stimulation (tACS) frequency and intensity to eliminate phosphene perception (e.g., tACS studies using verum tACS group and sham group) or, on the contrary, to maximize perception of phosphenes in order to be more able to study their dynamics. In this study, subjective reports of 50 healthy subjects exposed to different intensities of retinal tACS at 4 different frequencies (6, 10, 20 and 40 Hz) were analyzed. The effectiveness of different tACS frequencies in inducing phosphenes was at least 92 %. Subject reported 41 different phosphene types; the most common were light flashes and light circles. Changing the intensity of stimulation often induced a change in phosphene attributes. Up to nine phosphene attributes changed when the tACS intensity was changed. Significant positive correlation was observed between number of a different phosphene types and tACS frequency. Based on these findings, it can be concluded that tACS is effective in eliciting phosphenes whose type and attributes change depending on the frequency and intensity of tACS. The presented results open new questions for future research.
Extracellular vesicles are small membrane particles (30-1000 nm) released by Bacteria, Eukaryotes and Archaea. They have been shown to play an important role in intracellular and intercellular communication, within and between kingdoms via transport of bioactive molecules. Thus, they can be involved in altering gene expression and regulation of physiological and pathological processes of the recipient. Their unique properties make extracellular vesicles a perfect candidate vector for targeted drug delivery or a biomarker. For a long time, animal and mainly mammal extracellular vesicles have been used in research. But for plants, there had been speculations about the existence of nanovesicles due to the presence of a cell wall. Today, awareness of plant extracellular vesicles is on the rise and their research has proved they have various functions, such as protein secretion, transport of bioactive molecules or defense against pathogens. Further potential of plant extracellular vesicles is stressed in this review.
Plant volatiles can synergize the response to moth pheromone. Synthetic pheromone analogs, in turn, have the opposite effect in reducing pheromone attractiveness. To determine how these two types of stimuli interact and influence male moth behaviour, we performed wind tunnel experiments on the grapevine moth, Lobesia botrana. We noticed that a blend of host plant volatiles [(E)-β-caryophyllene, 1-hexanol, (Z)-3-hexenyl acetate and 1-octen-3-ol in a 100:20:10:5 ratio] significantly increased the response of males to an optimized blend of sex pheromone [(7E,9Z)-dodeca-7,9-dienyl acetate (E7,Z9-12:Ac), (7E,9Z)- dodeca-7,9-dienol (E7,Z9-12:OH) and (Z)-9-dodecenyl acetate (Z9-12:Ac)] in a 100:10:2 ratio. However, the response of males to the natural attractant was significantly reduced by two analogs [(9E,11Z)-tetradeca-9,11-dien-2-one (MK 2) and [(9E,11Z)-1,1,1-trifluoro-tetradeca-9,11-dien-2-one (TFMK 3)], of the major component of the sex pheromone of the insect (E7,Z9-12:Ac). When both stimuli were tested on males at pheromone:analog:plant volatile blend 1:100:1000 ratio, the plant blend offset the inhibitory effect induced by TFMK 3 but not that of MK 2. Our results show for the first time that under laboratory conditions plant volatiles can prevent inhibition by a pheromone analog., Albert Sans, Miguel Morán, Magí Riba, Ángel Guerrero, Jaume Roig, César Gemeno., and Obsahuje bibliografii
Peripheral insulin resistance is associated with decreasing adiponectin and increasing leptin plasma levels, and also with cognitive decline. The effects of adipokines on brain function have been published from both animal and human studies. In particular, the influence of leptin and adiponectin on the development of Alzheimer’s disease (AD) has been extensively investigated. However, the association between adipsin and AD is as yet unknown. In 37 patients with AD and 65 controls that followed the same study protocol, we tested whether adiponectin, leptin, and adipsin could be used as biomarkers in the early stages of AD. In contrast with conclusions of cognition studies in insulin resistant states, our study found a correlation of impaired neuropsychological performance with increasing adiponectin and decreasing leptin in AD patients. Nevertheless, no significant differences between patients and controls were found. AD women had significantly increased adipsin compared to controls, and there was a positive correlation of adipsin with age and disease duration. Although adipokines do not appear to be suitable biomarkers for early AD diagnosis, they certainly play a role in the pathogenesis of AD. Further studies will be needed to explain the cause of the adipokine “breaking point” that leads to the pathogenesis of overt AD., Markéta Vaňková, Gabriela Vacínová, Josef Včelák, Daniela Vejražková, Petra Lukášová, Robert Rusina, Iva Holmerová, Eva Jarolímová, Hana Vaňková, Běla Bendlová., and Obsahuje bibliografii
Toxoplasma gondii Nicolle et Manceaux, 1909, the etiologic agent of toxoplasmosis, was considered a clonal population with three distinct genetic lineages (I, II and III); however, sequence analysis of different strains has revealed distinct atypical genotypes. Macrophages are essential for immunity against toxoplasmosis and differential cell regulation may affect the course of the disease. In this context, our study aims to investigate the infection by TgChBrUD2, a highly virulent atypical Brazilian strain of T. gondii, on the activation and polarisation of human macrophages. Human macrophage-like cells obtained from THP-1 cells were infected with TgChBrUD2, RH or ME49 strains of T. gondii to evaluate the impact of parasite infection on macrophage polarisation. Our results indicate that the TgChBrUD2 and ME49 strains of T. gondii induced a classic activation of human macrophages, which was confirmed by the high rate of spindle-shaped macrophages, low amount of urea and increase in the levels of nitrite, as well as the down-regulation of M2-markers. In contrast, RH strain promoted an alternative activation of macrophages. The polarisation of human macrophages towards an M1 subtype mediated by TgChBrUD2 and ME49 strains resulted in a low parasite burden, with high levels of IL-6 and MIF. Finally, the M2 subtype triggered by the RH strain culminated in a lower intracellular proliferation index. We concluded that the atypical (TgChBrUD2) and clonal (ME49) strains are able to elicit an M1 subtype, which results in parasitism control, partially explained by the high levels of IL-6 and MIF produced during the infection by these genotypes. In contrast, the clonal (RH) strain promoted a macrophage polarisation towards an M2 subtype, marked by a high parasite burden, with a weak modulation of pro-inflammatory cytokines. Thus, atypical strains can present different mechanisms of pathogenicity and transmissibility compared to clonal strains, as well as they can use distinct strategies to evade the host's immune response and ensure their survival.
Lygus lineolaris (Palisot de Beauvois, 1818) (tarnished plant bug) is a serious pest of cotton (Gossypium hirsutum L.) in the Delta region as compared to cotton in the Hills region of the state of Mississippi in USA. The reason for this is unclear but it was hypothesized that the plant cell wall degrading polygalacturonase enzyme system in the salivary glands of L. lineolaris from the Delta could be better adapted for cotton, which is grown more predominantly in the Delta region than in the Hills region. Expression analysis of three primary polygalacturonase genes (LlPG1, LlPG2 and LlPG3) was conducted in laboratory reared and field collected populations of L. lineolaris. Assay of polygalacturonase enzyme activity was also conducted to compare wild collected populations. Initial laboratory and field data revealed gene expression differences in sex, age, region, and host plant which guided the direction of our subsequent study during 2013 and 2014. Based on the results of this study, we propose that the three genes studied may not be reflective of the entire polygalacturonase enzyme system and may not be solely responsible for the observed adaptation of L. lineolaris to cotton in the Delta region than in the Hills region. Analyses also revealed that the expression of the three targeted polygalacturonase genes was affected by the host plant from which the insects were collected and that adults had higher polygalacturonase expression than nymphs. Taken together, our results provide strong evidence for developmental stage specific and host plant based change in expression of PG genes in the salivary glands of L. lineolaris. This, however, was not reflected in total polygalacturonase enzyme activity which was not significantly different between regions, hosts, sex, or developmental stage., Daniel Fleming, Natraj Krishnan, Fred Musser., and Obsahuje bibliografii
This study reports seasonal presence of Coccinella septempunctata L. (Coleoptera: Coccinellidae) in Southeast Turkey, in 2008, 2009 and 2010. Samples were collected from crops in agricultural areas at altitudes of 10 m, 800 m and 1400 m from stands of wild herbaceous plants , and at 1750 m from stone debris fields. First C. septempunctata adults were collected at the beginning of June at Tentcamp (800 m) and Tozlu (1400 m), early in July at Sarikiz (1700 m) when the mean air temperature reached 30°C. Adults became active in spring, after aestivating around Sarikiz and overwintering there under snow. First adults emerged on 2nd April in 2009 around Edremit Gulf when mean air temperature reached 14.8°C. Adult and immature stages of C. septempunctata were recorded attacking aphid populations till the end of June. C. septempunctata was present there for only one period each year during which they completed one generation. Adult individuals of this generation returned to Mount Ida to aestivate. Maximum numbers of adults present on Mount Ida in the first week of August in 2009 and 2010 were recorded. C. septempunctata adults aestivate and overwinter at Sarikiz on Mount Ida after completing their development on aphids in April, May and June around Edremit Gulf., Ali Özpinar, Ali Kürşat Şahin, Burak Polat., and Obsahuje bibliografii
The ladybird beetle, Cheilomenes sexmaculata (Fabricius), has been extending its distribution in and around urban areas at higher latitudes in Japan over the past 100 years. Between 2003 and 2011, we investigated the seasonal occurrence, aphid prey and population dynamics of this species in an urban park in Osaka City, central Japan. We found that C. sexmaculata completes three generations a year in Osaka. Overwintered adults emerge in March or April and produce two (or rarely one) generations by summer. Second-generation adults aestivate and subsequently produce another generation in autumn. This species feeds on five species of aphids that infest planted shrubs and alien weeds throughout the vegetative season. We analyzed the association between accumulated temperature and when overwintered adults first emerged. In addition, we determined the association between their time of emergence, peak abundance and last occurrence, and meteorological conditions. There was no association between the sum of effective temperatures and termination of adult overwintering. There was, however, an association between first occurrence and peak abundance, and climatic conditions, such as warm temperatures or low humidity. This species maintained a stable population in an urban park by becoming quiescent when climatic conditions were unfavourable or prey was scarce. We discussed these findings in relation to urban environmental factors, such as climate, food conditions and vegetation., Yasuko Kawakami, Kazuo Yamazaki, Kazunori Ohashi., and Obsahuje bibliografii
Mental disorders affect 10-20 % of the young population in the world. Major depressive disorder (MDD) is a common mental disease with a multifactorial and not clearly explained pathophysiology. Many cases remain undetected and untreated, which influences patients’ physical and mental health and their quality of life also in adulthood. The aim of our pilot study was to assess the prediction value of selected potential biomarkers, including blood cell counts, blood cell ratios, and parameters like peroxiredoxin 1 (PRDX1), tenascin C (TNC) and type IV collagen (COL4) between depressive pediatric patients and healthy peers and to evaluate a short effect of antidepressant treatment. In this study, 27 young depressive patients and 26 non-depressed age-matched controls were included. Blood analyses and immunological assays using commercial kits were performed. Platelet count was the only blood parameter for which the case/control status was statistically significant (p=0.01) in a regression model controlling for the age and gender differences. The results from ELISA analyses showed that the case/control status is a significant predictor of the parameters PRDX1 (p=0.05) and COL4 (p=0.009) in respective regression model considering the age and gender differences between MDD patients and controls. A major finding of this study is that values of platelet count, monocyte to lymphocyte ratio, white blood cell, and monocyte counts were assessed by the Random Forest machine learning algorithm as relevant predictors for discrimination between MDD patients and healthy controls with a power of prediction AUC=0.749.