scholarly journals NATURAL RESISTANCE OF BAMBUSA VULGARIS TO TERMITE AND POWDER-POST BEETLE ATTACK

2021 ◽  
Vol 33 (4) ◽  
pp. 398-405
Author(s):  
NA Sadiku ◽  
OS Bada ◽  
AO Oluyege ◽  
B Ajayi
1989 ◽  
Vol 61 (03) ◽  
pp. 517-521 ◽  
Author(s):  
Walter E Laug ◽  
Ruedi Aebersold ◽  
Ambrose Jong ◽  
Willian Rideout ◽  
Barbara L Bergman ◽  
...  

SummaryLarge arteries have a natural resistance to tumor cell invasion thought to be due to the production of protease inhibitors. Vascular smooth muscle cells (VSMC) representing the major cellular part of arteries were isolated from human aortas and grown in tissue culture. These cells were found to produce large amounts of inhibitors of plasminogen activators (PA). Fractionation of VSMC-conditioned medium by heparin-affigel chromatography separated three immunologically and functionally distinct PA inhibitors (PAI), namely PAI-1, PAI-2 and protease-nexin I. The three inhibitors were characterized by functional assays and immunoblotting. PA inhibitor 2 (PAI-2) had little affinity for heparin, whereas PA inhibitor 1 (PAI-l) bound to heparin and was eluted from the column at NaCl concentrations of 0. 1 to 0.35 M. Protease-nexin I, eluted at NaCl concentrations of 0.5 M and higher. Most of the PAI-1 was present in the latent, inactive form. PAI-1 was further purified by ion exchange chromatography on a Mono-Q column. Partial sequencing of the purified PAI-1 confirmed its nature by matching completely with the sequence deduced from the cDNA nucleotide sequence of endothelial cell PAI-1. Thus, human VSMC produce all three presently known PAI and these can be separated in a single heparin affinity purification step.


2019 ◽  
Vol 1 (9) ◽  
pp. 38-46
Author(s):  
A. P. Babkin ◽  
A. A. Zuikova ◽  
O. N. Krasnorutskaya ◽  
Yu. A. Kotova ◽  
D. Yu. Bugrimov ◽  
...  

The widespread worldwide spread of acute respiratory diseases is an urgent problem in health care. Expressed polyetiology of respiratory diseases does not allow to limit the use of specific vaccine preparations and dictates the need to use to combat them a variety of non-specific means that stimulate the natural resistance of the human body. The main pharmacological action of sodium deoxyribonucleate is the stimulation of phagocytic activity of T-helpers and T-killers, increasing the functional activity of neutrophils and monocytes/ macrophages, providing regeneration and repair processes in the epithelial component of antiviral protection of the body. Based on the above, the study of the clinical efficacy of Derinat® in the form of spray in the treatment of acute respiratory viral infections is relevant.


Agrotek ◽  
2018 ◽  
Vol 2 (3) ◽  
Author(s):  
Alexander Yaku

Taro beetles, Papuana spp., (Coleoptera: Scarabaeidae) are pests of taro (Colozasia esculenta) and a number of other plants in the South Pacific regions including Papua. The pest have become serious threat for taro farmers because it damage corm resulting in the loss of production. To control the taro beetle, 104 taro cultivars were evaluated for their natural resistance. The experiment was conducted in the Unipa Farm located in East Amban. Results of research shows that there are three cultivars being highly resistance and 36 cultivars being only resistance. The taro with white colour of corm flesh seems to be a non-preference factor that alter insect behavior, resulting in the selection of alternate taro cultivars.


Author(s):  
М.В. ДОВЫДЕНКОВА

Проведена статистическая обработка сформированной базы данных показателей неспецифической резистентности MS «Excel» с целью изучения динамики иммунитета по параметрам бактерицидной, лизоцимной и фагоцитарной активности у крупного рогатого скота черно-пестрой породы разных возрастов. Было установлено, что средние значения показателей лизоцимной и бактерицидной активности у телят в 6 мес были ниже (47,89% и 49,09%, соответственно), чем у животных в 3—4 года (53,75% и 52,81%). Выведено уравнение регрессии, описывающее взаимосвязь между средними показателями фагоцитарной активности и возрастом при высокой степени достоверности (R2=0,90). Изменения лизоцимной и бактерицидной активности в зависимости от возраста были недостоверными (R2=0,58 и R2=0,49, соответственно). Установлена высокая корреляция между бактерицидной и лизоцимной активностью. Отмечена динамика изменения неспецифического иммунитета у коров различных возрастных групп. Создание баз данных и постоянный мониторинг основных показателей естественной резистентности в зависимости от различных факторов (породы, возраста, стадий лактации, кормления, способов содержания), которые влияют на данные показатели, необходимо для оценки физиологического состояния организма животных и их устойчивости к болезням. Statistical processing of the generated MS "Excel" on indicators of non-specific resistance database was carried out with the aim of studying the dynamics of the development of immunity in terms of bactericidal, lysozyme and phagocytic activity in black-and-white cattle of different ages. It was found that the average values of indicators of lysozyme and bactericidal activity in calves at 6 months were lower (47.89% and 49.09%, respectively) than in animals at the age of 3—4 years (53.75% and 52.81%). The equation of regression was derived, it describes the relationship between the average indicators of phagocytic activity and the age with a high degree of reliability (R2=0.90). The changes in lysozyme and bactericidal activity depending on age were dubious (R2=0.58 and R2=0.49, respectively). The high correlation between bactericidal and lysozyme activity was established. It was noticed that the cows of different age groups experienced the dynamics of changes in nonspecific immunity. The creation of databases and constant monitoring of the main indicators of natural resistance, depending on various factors (breed, age, stages of lactation, feeding, methods of keeping) that affect these indicators, is necessary for assessing the physiological state of the animals’ body of and their resistance to diseases.


Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 340
Author(s):  
Ilze Matisone ◽  
Roberts Matisons ◽  
Āris Jansons

The dieback of common ash (Fraxinus excelsior L.) has dramatically decreased the abundance of the species in Europe; however, tolerance of trees varies regionally. The tolerance of trees is considered to be a result of synergy of genetic and environmental factors, suggesting an uneven future potential of populations. This also implies that wide extrapolations would be biased and local information is needed. Survival of ash during 2005–2020, as well as stand- and tree-level variables affecting them was assessed based on four surveys of 15 permanent sampling plots from an eastern Baltic region (Latvia) using an additive model. Although at the beginning of dieback a relatively low mortality rate was observed, it increased during the 2015–2020 period, which was caused by dying of the most tolerant trees, though single trees have survived. In the studied stands, ash has been gradually replaced by other local tree species, though some recruitment of ash was locally observed, implying formation of mixed broadleaved stands with slight ash admixture. The survival of trees was related to tree height and position within a stand (relative height and local density), though the relationships were nonlinear, indicating presence of critical conditions. Regarding temporal changes, survival rapidly dropped during the first 16 years, stabilizing at a relatively low level. Although low recruitment of ash still implies plummeting economic importance of the species, the observed responses of survival, as well as the recruitment, imply potential to locally improve the survival of ash via management (tending), hopefully providing time for natural resistance to develop.


2021 ◽  
Vol 13 (15) ◽  
pp. 8164
Author(s):  
Brian E. Bautista ◽  
Lessandro E. O. Garciano ◽  
Luis F. Lopez

There are limited published studies related to the mechanical properties of bamboo species in the Philippines. In this study, the shear strength properties of some economically viable bamboo species in the Philippines were properly characterized based on 220 shear test results. The rationales of selecting this mechanical property are the following: (1) Shear strength, parallel to the fiber, has the highest variability among the mechanical properties; and (2) Shear is one of the governing forces on joint connections, and such connections are the points of failure on bamboo structures when subjected to extreme loading conditions. ISO 22157-1 (2017) test protocol for shear was used for all tests. The results showed that Bambusa blumeana has the highest average shear strength, followed by Gigantochloa apus, Dendrocalamus asper, Bambusa philippinensis, and Bambusa vulgaris. However, comparative analysis, using One-way ANOVA, showed that shear strength values among these bamboo species have significant differences statistically. A linear regression model is also established to estimate the shear strength of bamboo from the physical properties. Characteristic shear strength is also determined using ISO 12122-1 (2014) for future design reference.


Author(s):  
Elihu Aranday-Cortes ◽  
C Patrick McClure ◽  
Christopher Davis ◽  
William L Irving ◽  
Kazeem Adeboyejo ◽  
...  

Abstract Background Chronic hepatitis C virus (HCV) infection affects 71 million individuals, mostly residing in low- and middle-income countries (LMICs). Direct-acting antivirals (DAAs) give high rates of sustained virological response (SVR) in high-income countries where a restricted range of HCV genotypes/subtypes circulate. Methods We studied United Kingdom–resident patients born in Africa to examine DAA effectiveness in LMICs where there is far greater breadth of HCV genotypes/subtypes. Viral genome sequences were determined from 233 patients. Results Full-length viral genomic sequences for 26 known subtypes and 5 previously unidentified isolates covering 5 HCV genotypes were determined. From 149 patients who received DAA treatment/retreatment, the overall SVR was 93%. Treatment failure was associated primarily with 2 subtypes, gt1l and gt4r, using sofosbuvir/ledipasvir. These subtypes contain natural resistance-associated variants that likely contribute to poor efficacy with this drug combination. Treatment failure was also significantly associated with hepatocellular carcinoma. Conclusions DAA combinations give high SVR rates despite the high HCV diversity across the African continent except for subtypes gt1l and gt4r, which respond poorly to sofosbuvir/ledipasvir. These subtypes are widely distributed across Western, Central, and Eastern Africa. Thus, in circumstances where accurate genotyping is absent, ledipasvir and its generic compounds should not be considered as a recommended treatment option.


2021 ◽  
Author(s):  
Jie He ◽  
Nico Rössner ◽  
Minh T T Hoang ◽  
Santiago Alejandro ◽  
Edgar Peiter

Abstract Calcium (Ca2+) and manganese (Mn2+) are essential elements for plants and have similar ionic radii and binding coordination. They are assigned specific functions within organelles, but share many transport mechanisms to cross organellar membranes. Despite their points of interaction, those elements are usually investigated and reviewed separately. This review takes them out of this isolation. It highlights our current mechanistic understanding and points to open questions of their functions, their transport, and their interplay in the endoplasmic reticulum (ER), vesicular compartments [Golgi apparatus, trans-Golgi Network (TGN), prevacuolar compartment (PVC)], vacuoles, chloroplasts, mitochondria, and peroxisomes. Complex processes demanding these cations, such as Mn2+-dependent glycosylation or systemic Ca2+ signaling, are covered in some detail if they have not been reviewed recently or if recent findings add to current models. The function of Ca2+ as signaling agent released from organelles into the cytosol and within the organelles themselves is a recurrent theme of this review, again keeping the interference by Mn2+ in mind. The involvement of organellar channels [e.g., Glutamate-Receptor-Likes (GLRs), Cyclic-Nucleotide-Gated Channels (CNGCs), Mitochondrial Conductivity Units (MCUs), Two-Pore Channel1 (TPC1)], transporters [e.g., Natural-Resistance-Associated Macrophage Proteins (NRAMPs), Calcium Exchangers (CAXs), Metal-Tolerance Proteins (MTPs), Bivalent-Cation Transporters (BICATs)] and pumps [Autoinhibited Ca2+-ATPases (ACAs), ER Ca2+-ATPases (ECAs)] in the import and export of organellar Ca2+ and Mn2+ is scrutinized, whereby current controversial issues are pointed out. Mechanisms in animals and yeast are taken into account where they may provide a blueprint for processes in plants, in particular with respect to tunable molecular mechanisms of Ca2+-versus-Mn2+ selectivity.


2014 ◽  
Vol 2014 ◽  
pp. 1-20 ◽  
Author(s):  
H. V. Lee ◽  
S. B. A. Hamid ◽  
S. K. Zain

Lignocellulosic biomass is a complex biopolymer that is primary composed of cellulose, hemicellulose, and lignin. The presence of cellulose in biomass is able to depolymerise into nanodimension biomaterial, with exceptional mechanical properties for biocomposites, pharmaceutical carriers, and electronic substrate’s application. However, the entangled biomass ultrastructure consists of inherent properties, such as strong lignin layers, low cellulose accessibility to chemicals, and high cellulose crystallinity, which inhibit the digestibility of the biomass for cellulose extraction. This situation offers both challenges and promises for the biomass biorefinery development to utilize the cellulose from lignocellulosic biomass. Thus, multistep biorefinery processes are necessary to ensure the deconstruction of noncellulosic content in lignocellulosic biomass, while maintaining cellulose product for further hydrolysis into nanocellulose material. In this review, we discuss the molecular structure basis for biomass recalcitrance, reengineering process of lignocellulosic biomass into nanocellulose via chemical, and novel catalytic approaches. Furthermore, review on catalyst design to overcome key barriers regarding the natural resistance of biomass will be presented herein.


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