Effects of Different Nutritional Conditions on the Growth and Reproduction of Nilaparvata lugens (Stål)

Growth and reproduction are the two most basic life processes of organisms and the distribution of energy in these processes is a core issue of the life history of organisms. Nilaparvata lugens (Stål), the brown planthopper (BPH), is a single-feeding rice pest. In the present study, this species was used as a model for testing the effects of nutritional conditions on various growth and reproduction indicators. First, the third-instar nymphs were fed with three different concentrations (100, 50, and 25%) of artificial diet until the second day of adulthood. The results showed that as the nutrient concentration decreased, the body development and oviposition of BPH were hindered. The total lipid content in the fat bodies was also significantly reduced. RT-PCR analysis showed compared to the 100% concentration group, the expression levels of vitellogenin (Vg) genes in the fifth-instar nymphs, adults, and in different tissues (ovary, fat body, and other tissues) were significantly decreased in the 50 and 25% treatment groups. Western blot analysis showed that Vg protein expression was highest in the 100% group, followed by the 50% group, with no expression in the 25% group. These results indicate that growth and reproduction in the BPH are regulated by, or correlated with, nutrient concentration. This study is of great significance as it reveals the adaptive strategies of the BPH to nutritional deficiencies and it also provides valuable information for the comprehensive control of this pest.

An experimental study of the wound healing effect of ophthalmic drug films with 6-methyl-3-(thietan-3-yl)uracil and methyluracil

Purpose: to study experimentally the wound-healing effect of ophthalmic drug films (ODF) with 6-methyl-3-(thietan-3-yl) uracil and methyluracil. Material and methods. The study involved 17 Chinchilla rabbits (34 eyes), whose corneas were histomorphologically studied after an experimental chemical acid burn and treatment. ODF with 6-methyl-3-(thietan-3-yl)uracil were deposited in the right eyes of 15 rabbits (15 eyes), and ODF with methyluracil — in the left eyes of these rabbits. Two rabbits served as control: their right eyes were left without wound healing therapy, while the left eyes received dexpanthenol 5 % gel (corneregel) 4 times a day. All animals were monitored daily for 21 days. The morphological changes in the cornea were recorded on the 2nd, 7th, 14th and 21st days after the experimental chemical burn.Results. The course of reparative processes of the chemical burns of the cornea was found to be different depending on the drugs used. Our results show that the ODF with methyluracil led to the resorption of the edema and the turbidity, as well as to a total closure of the desquamation sites of the corneal epithelium on the 7th day. With the ODF containing 6-methyl-3-(thietan-3-yl) uracil, the effect was achieved on the 14th day. In contrast to the control, ODF enhanced the growth and reproduction of cells, rapidly improved the trophism, and stimulated the regeneration process in damaged corneal tissues. ODFs produced no toxic reactions, such as destruction of the collagen framework, maceration, pronounced edema, and hyperemia. On the 21st day of observation, the microscopic picture of rabbit cornea showed the usual normal structure. Conclusion. ODF therapy with methyluracil and 6-methyl-3-(thietan-3-yl)uracil leads to accelerated centripetal epithelialization of corneal erosion, more structured and histologically correct restoration of the epithelial-stromal layer.

The Prevalence of Pulmonary Aspergillosis Among Clinically Suspected and Undertreated Tuberculosis Patients in Khartoum State, Sudan

Background Respiratory tract aspergillosis is a pulmonary disease cause by aspergillus species which are opportunistic fungi that mainly infect immuno-compromised patients . Objective(s) The present study aimed to detect the frequency of pulmonary aspergillosis among clinically suspected and under follow up tuberculosis patients conducted at Tropical Diseases Teaching Hospital, Omdurman, Khartoum State , Sudan during the period from December 2019 to November 2020. Materials and Methods One hundred and fifty sputum samples were collected from suspected cases of pulmonary tuberculosis and under follow up tuberculosis patients. All specimens were examined using 20% KOH and cultured on two sets of Sabouraudʹs Dextrose agar slope media with chloramphenicol. Results Asperigillus species were isolated from 9/150 (6%) patients. They represented 5(3.3%) A.fumigatus, 3 (2%) A. niger and 1 (0.6%) A. Flavus. It was found that all Aspergillus isolates were revealed from Non acid fast bacilli (Non AFB) patients 9/137(6.6%) with the most common frequency among asymptomatic patients 3/35(8.6%) , patients who were under tuberculosis treatment (8.5%), those who were under Rifampicin (RIF) and Isonizide (INH) treatment (10%) and with duration of less than three month. Also the higher percentage (13%) was represented among the age group range from 61-80 year and slightly among males 6/97 (6.2 %) than females 3/53 (5.7%). There was statistically non-significant association between the frequency of aspergillosis and the studied variables in this study. Conclusion The frequency of pulmonary aspergillosis among patients with anti-tuberculosis treatment reflects the need for routine screening and diagnosis of those patients since the use of anti- tuberculosis treatment can promote the growth and reproduction of fungi. Keywords Pulmonary aspergillosis, tuberculosis, follow up patients.

Transcriptome Analysis of Jujube (Ziziphus jujuba Mill.) Response to Heat Stress

Heat stress (HS) is a common stress influencing the growth and reproduction of plant species. Jujube (Ziziphus jujuba Mill.) is an economically important tree with strong abiotic stress resistance, but the molecular mechanism of its response to HS remains elusive. In this study, we subjected seedlings of Z. jujuba cultivar “Hqing1-HR” to HS (45°C) for 0, 1, 3, 5, and 7 days, respectively, and collected the leaf samples (HR0, HR1, HR3, HR5, and HR7) accordingly. Fifteen cDNA libraries from leaves were constructed for transcriptomics assays. RNA sequencing and transcriptomics identified 1,642, 4,080, 5,160, and 2,119 differentially expressed genes (DEGs) in comparisons of HR1 vs. HR0, HR3 vs. HR0, HR5 vs. HR0, and HR7 vs. HR0, respectively. Gene ontology analyses of the DEGs from these comparisons revealed enrichment in a series of biological processes involved in stress responses, photosynthesis, and metabolism, suggesting that lowering or upregulating expression of these genes might play important roles in the response to HS. This study contributed to our understanding of the molecular mechanism of jujube response to HS and will be beneficial for developing jujube cultivars with improved heat resistance.

The auxin-inducible degron 2 (AID2) system enables controlled protein knockdown during embryogenesis and development in Caenorhabditis elegans

Targeted protein degradation using the auxin-inducible degron (AID) system is garnering attention in the research field of Caenorhabditis elegans, because of the rapid and efficient target depletion it affords, which can be controlled by treating the animals with the phytohormone auxin. However, the current AID system has drawbacks, i.e., leaky degradation in the absence of auxin and the requirement for high auxin doses. Furthermore, it is challenging to deplete degron-fused proteins in embryos because of their eggshell, which blocks auxin permeability. Here, we apply an improved AID2 system utilizing AtTIR1(F79G) and 5-Ph-IAA to C. elegans and demonstrated that it confers better degradation control vs. the previous system by suppressing leaky degradation and inducing sharp degradation using 1300-fold lower 5-Ph-IAA doses. We successfully degraded the endogenous histone H2A.Z protein fused to an mAID degron and disclosed its requirement in larval growth and reproduction, regardless of the presence of maternally inherited H2A.Z molecules. Moreover, we developed an eggshell-permeable 5-Ph-IAA analogue, 5-Ph-IAA-AM, that affords an enhanced degradation in laid embryos. Our improved system will contribute to the disclosure of the roles of proteins in C. elegans, in particular those that are involved in embryogenesis and development, through temporally controlled protein degradation.

Ecological Effects of Undaria pinnatifida (Harvey) Suringar and Nutrient-Enrichment on Intertidal Assemblages in the Wellington Region of New Zealand

<p>The introduction of non-native species and the alteration of seawater nutrient regimes due to anthropogenic impacts are two important threats to marine environments. Moreover, these disturbances may interact in such a way that promotes the success of invasive species in coastal habitats. This thesis contributes to current gaps in knowledge in these areas for low-intertidal communities. Algal community dynamics and ecological effects of the invasive kelp Undaria pinnatifida on low shores in the Wellington region, New Zealand, were examined, using field surveys and experiments. In addition, the role of variability in nutrient concentrations in coastal waters in mediating algal community structure and diversity, and the success of U. pinnatifida reproduction were investigated. Algal surveys were used in two locations thought to differ in nutrient regimes, the Wellington Harbour and the Wellington south coast, to explore the structure and dynamics of algal assemblages. Results showed high variability of low-intertidal algal communities among sites, but no consistent differences in algal community composition were found between the two locations, despite higher U. pinnatifida cover in the harbour. Over the duration of the study, nutrient regimes did not differ greatly between the locations. The response of rocky intertidal algal assemblages to chronic exposure to high nutrient effluent was investigated using two nearshore sewage outfalls in the Wellington region. The Titahi Bay outfall showed a stronger relationship between nutrients and algal community composition. Variation in algal assemblage structure and diversity was best explained by phosphate concentrations. By contrast, at the more wave-exposed Pencarrow outfall, patterns of change in the algal community were less clear and there was a much weaker relationship with seawater nutrients. Because removal of native algal canopy species may facilitate the establishment of invasive macroalgae, the invasion process of U. pinnatifida in disturbed patches in a rocky low-intertidal habitat was investigated. In a site where U. pinnatifida had not yet established, patches were scraped clear of native algal cover at two different times of year, and recruitment of U. pinnatifida was monitored. While U. pinnatifida invaded the site, it recruited in control plots at a similar rate as cleared plots, suggesting that physical disturbance of the native algal assemblage is not a key requirement for this kelp to invade and establish in new areas in the low intertidal zone. The response of native algal assemblages to removal of U. pinnatifida individuals was investigated at intertidal sites in the Wellington Harbour and on the south coast. No significant effect of U. pinnatifida on community composition, diversity, and species richness was detected. Removal of this invader did not change native intertidal assemblage structure in either harbour or south coast sites. Lastly, effects of different nutrient regimes and light intensities on early development and reproduction of U. pinnatifida were studied using a laboratory experiment. Under low light conditions U. pinnatifida gametophyte growth and reproduction stalled and was not increased by the addition of nutrients. However, at medium and high light levels, gametophyte growth and reproduction, and particularly early stage sporophyte growth rates increased when exposed to higher nutrient concentrations.These effects could have implications for U. pinnatifida population dynamics in intertidal habitats where light is not often a limiting resource. This research contributed to a better understanding of factors that underlie invasion dynamics, distribution, and ecological effects of U. pinnatifida and seawater nutrient regimes on low-intertidal assemblages in the Wellington region. The outcomes can assist in setting up strategic environmental protection and conservation plans.</p>

Ecological Effects of Undaria pinnatifida (Harvey) Suringar and Nutrient-Enrichment on Intertidal Assemblages in the Wellington Region of New Zealand

<p>The introduction of non-native species and the alteration of seawater nutrient regimes due to anthropogenic impacts are two important threats to marine environments. Moreover, these disturbances may interact in such a way that promotes the success of invasive species in coastal habitats. This thesis contributes to current gaps in knowledge in these areas for low-intertidal communities. Algal community dynamics and ecological effects of the invasive kelp Undaria pinnatifida on low shores in the Wellington region, New Zealand, were examined, using field surveys and experiments. In addition, the role of variability in nutrient concentrations in coastal waters in mediating algal community structure and diversity, and the success of U. pinnatifida reproduction were investigated. Algal surveys were used in two locations thought to differ in nutrient regimes, the Wellington Harbour and the Wellington south coast, to explore the structure and dynamics of algal assemblages. Results showed high variability of low-intertidal algal communities among sites, but no consistent differences in algal community composition were found between the two locations, despite higher U. pinnatifida cover in the harbour. Over the duration of the study, nutrient regimes did not differ greatly between the locations. The response of rocky intertidal algal assemblages to chronic exposure to high nutrient effluent was investigated using two nearshore sewage outfalls in the Wellington region. The Titahi Bay outfall showed a stronger relationship between nutrients and algal community composition. Variation in algal assemblage structure and diversity was best explained by phosphate concentrations. By contrast, at the more wave-exposed Pencarrow outfall, patterns of change in the algal community were less clear and there was a much weaker relationship with seawater nutrients. Because removal of native algal canopy species may facilitate the establishment of invasive macroalgae, the invasion process of U. pinnatifida in disturbed patches in a rocky low-intertidal habitat was investigated. In a site where U. pinnatifida had not yet established, patches were scraped clear of native algal cover at two different times of year, and recruitment of U. pinnatifida was monitored. While U. pinnatifida invaded the site, it recruited in control plots at a similar rate as cleared plots, suggesting that physical disturbance of the native algal assemblage is not a key requirement for this kelp to invade and establish in new areas in the low intertidal zone. The response of native algal assemblages to removal of U. pinnatifida individuals was investigated at intertidal sites in the Wellington Harbour and on the south coast. No significant effect of U. pinnatifida on community composition, diversity, and species richness was detected. Removal of this invader did not change native intertidal assemblage structure in either harbour or south coast sites. Lastly, effects of different nutrient regimes and light intensities on early development and reproduction of U. pinnatifida were studied using a laboratory experiment. Under low light conditions U. pinnatifida gametophyte growth and reproduction stalled and was not increased by the addition of nutrients. However, at medium and high light levels, gametophyte growth and reproduction, and particularly early stage sporophyte growth rates increased when exposed to higher nutrient concentrations.These effects could have implications for U. pinnatifida population dynamics in intertidal habitats where light is not often a limiting resource. This research contributed to a better understanding of factors that underlie invasion dynamics, distribution, and ecological effects of U. pinnatifida and seawater nutrient regimes on low-intertidal assemblages in the Wellington region. The outcomes can assist in setting up strategic environmental protection and conservation plans.</p>