scholarly journals Developmental decisions in Aspergillus nidulans are modulated by Ras activity.

1994 ◽  
Vol 14 (8) ◽  
pp. 5333-5348 ◽  
Author(s):  
T Som ◽  
V S Kolaparthi
Keyword(s):  
Aspergillus Nidulans ◽  
Essential Gene ◽  
Cell Types ◽  
Tube Formation ◽  
Stage Of Development ◽  
Initial Stage ◽  
Concentration Threshold ◽  
High Level ◽  
Multicellular Organisms ◽  
Further Development

To better understand how Ras controls development of multicellular organisms, we have chosen Aspergillus nidulans as a model system. When grown on solid medium, this fungus follows a well-defined program of development, sequentially giving rise to several cell types which produce three distinct structures: vegetative hyphae, aerial hyphae, and the conidiophore structure. Here we describe a ras homolog found in this fungus (Aras) and demonstrate that it is an essential gene that regulates the ordered program of development. We created dominant alleles of this gene and expressed them to different levels in order to vary the ratio of GTP-bound (active) to GDP-bound (inactive) A-Ras protein. When the amount of active Ras is large, nuclear division proceeds, but further development is inhibited at the early step of germ tube formation. At an intermediate level of active Ras, aerial hypha formation is inhibited, while at a low level, conidiophore formation is inhibited. Maintenance of an even lower level of the active Ras is essential for initiation and progression of conidiophore formation, the final stage of development. When the level of active Ras is artificially lowered, each stage of development is initiated prematurely except germination, the initial stage of development. Therefore, the progression of the ordered developmental pathway of A. nidulans is dependent upon an initial high level of active Ras followed by its gradual decrease. We propose that several concentration threshold exist, each of which allows development to proceed to a certain point, producing the proper cell type while inhibiting further development.

Developmental decisions in Aspergillus nidulans are modulated by Ras activity

1994 ◽  
Vol 14 (8) ◽  
pp. 5333-5348
Author(s):  
T Som ◽  
V S Kolaparthi
Keyword(s):  
Aspergillus Nidulans ◽  
Essential Gene ◽  
Cell Types ◽  
Tube Formation ◽  
Stage Of Development ◽  
Initial Stage ◽  
Concentration Threshold ◽  
High Level ◽  
Multicellular Organisms ◽  
Further Development

To better understand how Ras controls development of multicellular organisms, we have chosen Aspergillus nidulans as a model system. When grown on solid medium, this fungus follows a well-defined program of development, sequentially giving rise to several cell types which produce three distinct structures: vegetative hyphae, aerial hyphae, and the conidiophore structure. Here we describe a ras homolog found in this fungus (Aras) and demonstrate that it is an essential gene that regulates the ordered program of development. We created dominant alleles of this gene and expressed them to different levels in order to vary the ratio of GTP-bound (active) to GDP-bound (inactive) A-Ras protein. When the amount of active Ras is large, nuclear division proceeds, but further development is inhibited at the early step of germ tube formation. At an intermediate level of active Ras, aerial hypha formation is inhibited, while at a low level, conidiophore formation is inhibited. Maintenance of an even lower level of the active Ras is essential for initiation and progression of conidiophore formation, the final stage of development. When the level of active Ras is artificially lowered, each stage of development is initiated prematurely except germination, the initial stage of development. Therefore, the progression of the ordered developmental pathway of A. nidulans is dependent upon an initial high level of active Ras followed by its gradual decrease. We propose that several concentration threshold exist, each of which allows development to proceed to a certain point, producing the proper cell type while inhibiting further development.

scholarly journals THE INITIAL STAGE OF DEVELOPMENT OF ACADEMIC ROWING IN THE KATERINOSLAV REGION IN THE LATE XIX – EARLY XX CENTURY: HISTORICAL EXPERIENCE AND TRADITIONS

2021 ◽  
Vol 6 (2) ◽  
pp. 71-86
Author(s):  
Baldzhy Ilona ◽  
Dolbysheva Nina ◽  
Salenko Galina
Keyword(s):  
Physical Culture ◽  
Theoretical Knowledge ◽  
Historical Experience ◽  
Stage Of Development ◽  
Initial Stage ◽  
Archival Documents ◽  
History Of ◽  
Main Factors ◽  
Further Development

At present, in the conditions of decentralization, considerable attention is paid to the study of historical experience and traditions of development of physical culture and sports movement in the regions of Ukraine. Analysis of scientific and methodological literature shows that such studies allow not only to expand theoretical knowledge of the history of physical culture and sports in Ukraine, but also to identify priority sports in the development of programs for the development of physical culture and sports. The aim is to study the historical experience of the development of academic rowing as a sport in the Katerinoslav region in the late XIX – early XX centuries and identifying the main factors that contributed to its further development. Material and methods. During the analysis the analysis and generalization of scientific and methodical literature, historical-logical, chronological, descriptive methods on the basis of studying of periodical, local lore literature, archival documents, photographic materials and other sources were used.

scholarly journals Xenograft heterotopic modeling of colorectal cancer of various cell types in athymic BALB/c nude mice

2020 ◽  
pp. 148-152
Author(s):  
К.А. Лунёва ◽  
О.Е. Клементьева ◽  
К.Э. Терновская ◽  
Е.А. Дубова ◽  
А.С. Лунёв
Keyword(s):  
Colorectal Cancer ◽  
Nude Mice ◽  
Cell Types ◽  
Culture Collection ◽  
Stage Of Development ◽  
High Prevalence ◽  
Subcutaneous Transplantation ◽  
Hct 116 ◽  
High Level ◽  
Ht 29

Введение. Высокий уровень заболеваемости колоректальным раком стимулирует поиск методов его своевременной диагностики и эффективной терапии, что, в свою очередь, предполагает использование адекватных животных моделей на стадиях разработки и доклинических исследований. Методика. Для моделирования гетеротопических ксенографтов были использованы клеточные культуры колоректального рака человека линий DLD-1, HCT 116 и HT-29. В качестве носителей опухолевых моделей были взяты мыши линии BALB/c nude. Суспензию клеток вводили подкожно в область лопатки с помощью шприца. Результаты. Полученные из Американской коллекции типовых культур (ATCC) клетки культивировали до достижения необходимого количества для моделирования ксенографтов (20 сут). Клетки линии HCT-116 культивировались активнее и образовывали монослой в 3 раза быстрее, чем клетки линии DLD-1 и HT-29. Выживаемость мышей после проведения процедуры подкожной ксенотрансплантации составляла 100%. Образование ксенографтов объемом около 1 см3 наблюдали на 17-е - 26-е сут после прививания клеток. Приживаемость введённых клеток составила 100% для линии HCT-116. Для клеток колоректального рака человека линий DLD-1 и HT-29 приживаемость составила 75% и 60%, соответственно. Заключение. При экспериментальном моделировании подкожных гетеротопических ксенографтов колоректального рака человека на мышах линии BALB/c nude была получена высокая степень воспроизводимости при 100%-ной выживаемости животных-носителей. Introduction. The high prevalence of colorectal cancer (СС) stimulates scientists and physicians to search methods for СС diagnosis and effective therapy, which requires appropriate animal models at the stage of development and preclinical studies. Methods. CC cell cultures (DLD-1, HCT 116, and HT-29) were used for heterotopic xenograft modeling in BALB/c nude mice. The cell suspension was injected subcutaneously with a syringe. Results. CC cells from ATCC (American Type Culture Collection) were cultivated until obtaining the required number of cells for xenograft modeling (20 days). The HCT-116 cell culture developed more actively and formed a monolayer three times faster than DLD-1 and HT-29 cells. Survival of the mice after subcutaneous transplantation was 100%. Xenografts of approximately 1 cm3 volume formed at 17-26 days after grafting. Transplantability of the injected cells was 100% for HCT-116, 75% for DLD-1, and 60% for HT-29. Conclusion. The experimental modeling of subcutaneous heterotopic CC xenografts in BALB/c nude mice showed a high level of reproducibility with absolute 100% - survival of recipient mice.

scholarly journals Implication of mating on oocyte development in red cotton bug, Dysdercus koenigii (Fabricius, 1775) (Heteroptera: Pyrrhocoridae)

2019 ◽  
Vol 88 (4) ◽  
pp. 333-348
Author(s):  
Kamal Kumar Gupta ◽  
Sunil Kayesth ◽  
Mohd Shazad ◽  
Shailendra Kumar
Keyword(s):  
Adult Development ◽  
Oocyte Development ◽  
Follicular Cells ◽  
Histological Changes ◽  
Squamous Cells ◽  
Stage Of Development ◽  
Initial Stage ◽  
Dysdercus Koenigii ◽  
Further Development ◽  
Old Females

Abstract The ovaries of Dysdercus koenigii are consisted of meroistic telotrophic ovarioles. Each ovariole can be differentiated into tropharium and vitellarium. The tropharium contains stem line oogonia, newly formed oocytes, trophocytes, prefollicular cells and follicular cells. The vitellarium possesses 10-12 developing oocytes. The developing oocytes are connected to the trophocytes, present in the tropharium, by nutritive cords. During premating period, the ovarioles change, resulting in increase the number of oocytes in the vitellarium. The developing oocytes in the initial stage of development are surrounded by columnar follicular cells, which are subsequently changed to cuboidal and squamous cells in a sequence. The process of vitellogenesis was initiated after 48 h of adult development with the appearance of perioocytic space. There was deposition of yolk material at the periphery of oocytes in the ovarioles of 72 h old females. The further development of oocytes and vitellogenesis remained suspended up to 12-14 days in the virgin females. On the other hand, mating stimulates the oocyte development and process of vitellogenesis. There were distinct morphometric and histological changes in the ovarioles as a consequence of mating; dimensions of vitellarium and oocytes of the mated female increased drastically. However, the size of tropharium and number of oocytes present in the vitellarium largely remained unchanged. The process of vitellogenesis also resumed followed by mating stimulus. Therefore, the oocytes were laden with yolk material; at this stage, the surrounded follicular layer is replaced by chorion.

A Study on Knowledge, Attitude, Awareness and Practice About HIV/AIDS among different age group of Karachi, Pakistan

2017 ◽  
Vol 3 (3) ◽  
pp. 328-333
Author(s):  
Safia Mehmood ◽  
Sheema Zia ◽  
Nida Aziz ◽  
Omama Sajid
Keyword(s):  
Hiv Transmission ◽  
Age Groups ◽  
World Population ◽  
Major Barrier ◽  
Initial Stage ◽  
Awareness Programs ◽  
And Gender ◽  
Strongly Agree ◽  
High Level ◽  
Lack Of Knowledge

The AIDS is one of the most complicated health problems of the 21st century and it threatens the world population. AIDS spread at an alarming rate. This was a descriptive study to determine the knowledge, awareness, and practice about HIV among different age groups. The study carried out in Karachi, Pakistan during the period of January 2016-april 2016, in which 82 peoples are participated; 65 peoples having age in between 18-30, people’s lies in 31-40 years, while only 4 peoples having age above 40. From which 91% peoples thought HIV is dangerous virus and 51% peoples having misconception that it cause AIDS on initial stage and does not have any effect on CD4+. Majority of peoples aware about transmission of AIDS through intercourse, and during pregnancy. But the study show the high level of misbelieve also in mode of transmission that HIV transmit through sweat, saliva etc. Majority of the peoples have knowledge that HIV-1 is the most common type found worldwide. Also large number of peoples have knowledge that HIV weak immune system by destroying CD4+ and require long exposure to progress AIDS. Less than 15% of peoples strongly agree that AIDS is common in women. This misconception reflex the lack of knowledge and awareness in the HIV transmission and gender relation. Also majority of peoples thought that lack of knowledge is major barrier in the proper cure of disease. So increasing knowledge by awareness programs; sexual prevention; by starting national testing resources and curing poverty will cured AIDS in Pakistan. Newly drugs are introduced which can stop the progression of AIDS.

COGNITIVIZATION — THE NEXT STAGE OF INFORMATIZATION OF EDUCATION

2018 ◽  
pp. 5-11
Author(s):  
A. S. Christochevskaya ◽  
S. A. Christochevsky
Keyword(s):  
Comparative Analysis ◽  
Learning Resources ◽  
Technical Base ◽  
Initial Stage ◽  
New Knowledge ◽  
Good Material ◽  
E Learning ◽  
New Material ◽  
High Level ◽  
Paper Method

Informatization of education has been going on for 30 years. During this time, a good material and technical base appeared in schools, there are repositories of e-learning resources to which teachers have access. However, it is difficult to use these e-learning resources due to their too large number and not always high level. It is advisable to introduce a system of reviews and recommendations, to conduct a comparative analysis, as well as to make reviews of resources on a particular subject/topic. In addition, the demand for e-learning resources is affected by the fact that education authorities encourage not so much the use of e-learning resources as their development by the teacher himself. In general, the load on teachers has increased instead of the promised saving of time and effort when using the e-learning resources. At the same time, many e-learning resources are not very effective, since they do not meet the requirements of cognitiveness (they contribute not to learning, but to simple memorization of the material). It is necessary to explore the process of learning new material: this will allow you to create cognitive e-learning resources and other resources that would help you with equal probability to successfully acquire new knowledge for students belonging to different psycho-types. At the initial stage of the study of any subject, it is more expedient to use the usual “paper” method, that is, a textbook and not overload the student’s brain with excessive information. Only when he has mastered the basic provisions, we can turn to e-learning resources, bearing in mind that they must be cognitive, that is, they are aimed at logical perception and rapid intuitive learning, only in this case e-learning resources can be considered effective. The conclusion is formulated that cognitiveness is the next stage of informatization of education after the stage of electronization.

Role of Transcriptional Read-Through in PRE Activity in Drosophila melanogaster

Acta Naturae ◽  
2016 ◽  
Vol 8 (2) ◽  
pp. 79-86 ◽  
Author(s):  
P. V. Elizar’ev ◽  
D. V. Lomaev ◽  
D. A. Chetverina ◽  
P. G. Georgiev ◽  
M. M. Erokhin
Keyword(s):  
Dna Sequences ◽  
Cell Types ◽  
Transcription Terminator ◽  
Response Elements ◽  
Polycomb Response Elements ◽  
The Individual ◽  
Multicellular Organisms ◽  
Different Cell Types ◽  
Main Factor

Maintenance of the individual patterns of gene expression in different cell types is required for the differentiation and development of multicellular organisms. Expression of many genes is controlled by Polycomb (PcG) and Trithorax (TrxG) group proteins that act through association with chromatin. PcG/TrxG are assembled on the DNA sequences termed PREs (Polycomb Response Elements), the activity of which can be modulated and switched from repression to activation. In this study, we analyzed the influence of transcriptional read-through on PRE activity switch mediated by the yeast activator GAL4. We show that a transcription terminator inserted between the promoter and PRE doesnt prevent switching of PRE activity from repression to activation. We demonstrate that, independently of PRE orientation, high levels of transcription fail to dislodge PcG/TrxG proteins from PRE in the absence of a terminator. Thus, transcription is not the main factor required for PRE activity switch.

CONNECTION g.307 G > A SNP POLYMORPHISM OF THE ALPHA-FUKOZYLTRASFERAZA 1 GENE WITH ECONOMIC-USEFUL TRAITS IN THE LARGE WHITE PIG BREED

2017 ◽  
Vol 54 ◽  
pp. 134-140
Author(s):  
H. S. Rudoman ◽  
V. M. Balatsky ◽  
V. Y. Nor ◽  
V. O. Vovk
Keyword(s):  
Genetic Structure ◽  
Information Content ◽  
Analysis Of Variance ◽  
Farm Animals ◽  
Daily Weight Gain ◽  
Fixation Index ◽  
Its Sequencing ◽  
Large White ◽  
Stage Of Development ◽  
High Level

One of the top priorities at the present stage of development of pig breeding remains the development of a set of measures aimed at increasing the resistance animals to various diseases, especially – to colibacteriosis .One of the recent and effective approaches to prevent colibacillosis is using markers of selection; it involves pig genotyping by genome locuses. Chosen locuses are associated with animal sensitivity to the disease and selection of the results of genotyping of animals with increased resistance. Due to researches, one of such locuses is alpha-fukozyltrasferаza 1 gene (FUT1). Gene FUT1 is located in chromosome 6. As a result of its sequencing in the swine breeds of Large White and Swedish Landrace, single-nucleotide polymorphism (g.307 G > A SNP) has been detected. AA genotype determines the resistance of animals to colibacteriosis, while AG and GG genotypes are susceptible to this disease. According to the results of previous studies, the positive effect of allele A was determined not only on the resistance of pigs to colibacteriosis, but also on indicators of fattening and meat productivity and on reproductive performance. In Ukraine, the studies of polymorphism FUT1 g.307 G > A SNP were held fragmentedly and only on certain populations of Ukrainian Meat and Large White breed but without establishing its association with the indicators of productivity of pigs. The aim of our work was to study the genetic structure of Ukrainian Large White breeds, type 1 and the establishment of association. g. 307 G > A SNP FUT1 gene with pigs indicators of productivity. For research the 96 samples of hair were used. DNA isolation from samples with biomaterial were carried out using ion exchange resin Chelex-100. Genotyping was performed by PCR-RFLP by method of Jorgensen et al. (2006). Using DNA analysis of this breeds locus FUT1 was determined by genetic structure. Allele frequency of allele G (0,573) and allele A (0,427) was established The distribution of genotype frequencies was not statistically significantly different from the theoretically expected, calculated by the Hardy-Weinberg criterion. Thus, according to the locus of FUT1 g.307 G > A, the breeds investigated are in a state close to the genetic equilibrium. The negative value of the fixation index by the locus FUT1 g.307 G > A indicates an excess of heterozygotes in the population, and hence the lack of targeted selection for this marker. The valuation was performed by calculating the PIC (polymorphic information content) – information content of polymorphism marker. In the analyzed pig herd for this marker, the PIC has an average value (0,367), which indicates the high level of polymorphism of the given locus and is favorable for the possibility of conducting a search for links between individual genotypes and indicators of productivity. To establish the association g.307 G > A SNP FUT1 gene with indicators of animal productivity, a one-way analysis of variance of the experimental data was used. Based on the results of a one-way analysis of variance, a significant effect of the genotypes of the FUT1gene (g.1849 G > C) on the indicator of the average daily weight gain (р ≤ 0,001), the thickness of the bacon at the level of the VI-VII vertebrae (p ≤ 0.01), reaching live weight of 100 kg (р ≤ 0,001) and breeding index of fattening qualities (р ≤ 0,01) was found. The parameter of the influence of the genetic factor on the test feature was 28,54%, 10,4%, 33,4% and 8,8% respectively. According to the investigated indicators of productivity, animals with genotype AA, which determines resistance to colibacteriosis, dominated the animals with genotypes GG and AG. Based on the results of our research and pre-published data, the multiple effect of the g.307 G > A SNP FUT1 gene is observed, which is associated with the indicators of productivity, which again confirms the polygenicity of the quantitative trait loci of farm animals. Taking into account a high level of polymorphism of the investigated gene and reliable associations of genotypes with indicators of productivity found, it can be recommended to carry out breeding of pigs using genetic information of the g.307 G > A SNP gene FUT1.

scholarly journals Enhanced Cognitive Walkthrough: Development of the Cognitive Walkthrough Method to Better Predict, Identify, and Present Usability Problems

2013 ◽  
Vol 2013 ◽  
pp. 1-17 ◽  
Author(s):  
Lars-Ola Bligård ◽  
Anna-Lisa Osvalder
Keyword(s):  
Medical Equipment ◽  
Development Process ◽  
Product Development Process ◽  
Infusion Pumps ◽  
Usability Problems ◽  
Cognitive Walkthrough ◽  
High Level ◽  
High Degree ◽  
Further Development ◽  
Potential Use

To avoid use errors when handling medical equipment, it is important to develop products with a high degree of usability. This can be achieved by performing usability evaluations in the product development process to detect and mitigate potential usability problems. A commonly used method is cognitive walkthrough (CW), but this method shows three weaknesses: poor high-level perspective, insufficient categorisation of detected usability problems, and difficulties in overviewing the analytical results. This paper presents a further development of CW with the aim of overcoming its weaknesses. The new method is called enhanced cognitive walkthrough (ECW). ECW is a proactive analytical method for analysis of potential usability problems. The ECW method has been employed to evaluate user interface designs of medical equipment such as home-care ventilators, infusion pumps, dialysis machines, and insulin pumps. The method has proved capable of identifying several potential use problems in designs.

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