251 research outputs found
Regulation of growth, patterning and cell fate-specification during imaginal disc regeneration in drosophila
No full textThe process of regeneration is immensely complicated and requires the exquisitely precise orchestration of growth, patterning and cell-fate specification. Drosophila melanogaster larval tissues have recently emerged as a useful model organism to study this process. These larval tissues are simple but experience complex gene expression to finally form the adult tissue. As such, Drosophila is an ideal model organism to study the complicated process of regeneration. In this study we have used the experimental tractability of Drosophila to investigate how growth, patterning, cell-fate specification and fate plasticity are regulated in regenerating imaginal discs.
Regenerative growth must be carefully controlled and constrained to prevent overgrowth and to allow correct organization of the regenerating tissue. However, the factors that restrict regenerative growth have not been identified. In this study, we have identified one mechanism that constrains regenerative growth, impairment of which leads to erroneous patterning of the final appendage. Regenerating discs with reduced levels of the RNA-regulator Brain tumor (Brat) exhibit enhanced regeneration but produce adult wings with disrupted margins. The loss of cell-fate specification is due to the aberrantly high expression of the pro-growth factor Myc and the self-renewal factor Chinmo. Thus, Brat ensures that the regenerating tissue forms the proper final structure by constraining expression of pro-regeneration genes.
Dissociation of imaginal disc cells has previously been carried out to enable flow cytometry and cell sorting to analyze cell cycle progression, cell size, gene expression, and other aspects of imaginal tissues. However, the lengthy dissociation protocols employed may alter gene expression, cell behavior and overall viability. In this study, we developed a new rapid and gentle method of dissociating the cells of wing imaginal discs that significantly enhanced cell viability and reduced the likelihood of gene expression changes. This method was successfully used to create a transcriptional profile of the regenerating tissue leading to the identification of many novel regulators of regeneration. We have also extended our investigation of regeneration to the antennal imaginal disc.
Drosophila imaginal discs have also been used to study cell-fate specification and plasticity, including homeotic changes and regeneration-induced transdetermination. In this study, we identified a change from antennal fate to eye fate induced by a Distal-less-GAL4 (DllGAL4) P-element insertion that is a mutant allele of Dll and expresses GAL4 in the antennal imaginal disc. While this fate change was not induced by tissue damage, it appeared to be a hybrid of transdetermination and homeosis. This plasticity appears to be unique to the DllGAL4 line, possibly due to cellular stress induced by the high GAL4 expression combined with the severity of the Dll mutation. Thus, we propose that even in the absence of tissue damage, other forms of cellular stress caused by high GAL4 expression can induce determined cell fates to change, and selector gene mutations can sensitize the tissue to these transformations.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2021-12-01The student, Syeda Nayab Abidi, accepted the attached license on 2019-11-07 at 12:27.The student, Syeda Nayab Abidi, submitted this Dissertation for approval on 2019-11-07 at 12:54.This Dissertation was approved for publication on 2019-11-11 at 14:20.DSpace SAF Submission Ingestion Package generated from Vireo submission #14532 on 2020-02-28 at 17:21:56Made available in DSpace on 2020-03-02T22:12:16Z (GMT). No. of bitstreams: 2
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Previous issue date: 2019-11-11Embargo set by: Seth Robbins for item 113879
Lift date: 2022-03-02T22:12:26Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 113879
Lift date: 2022-03-02T22:15:21Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 113879
Lift date: 2022-03-02T22:18:25Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemU of I Only Restriction Lifted for Item 113879 on 2022-03-03T10:15:13Z
"Marginalization of Muslim Girls in Higher Education: A Sociological Analysis on Issues and Challenges"
No full textIndian society till today is a traditional and culturally diverse .People in our society belongs to different class, caste, region and religion. Muslim constitutes India’s largest minority but educationally they are one of the most backward communities in the country. Muslim girls lag behind their male counterparts and women from other community in the country itself. Muslim girls from different socio-economic strata have a great deal of marginalization in their life situations. The absence of gender disaggregated data by religion, particularly in respect of literacy rate, enrollment rates at different stages of education, dropout rates etc., at national, states, district levels was a formidable bottleneck in the planning and development of strategies and programmes for education of Muslim girls at every level
Factors enabling and hindering an eLearning programme for nurses and midwives in Afghanistan
No full textAfghanistan faces an acute shortage of trained healthcare providers. To build capacity of nurses and midwives, in 2014 a private hospital in Afghanistan initiated an eLearning programme to enhance their knowledge and skills. The study was conducted to identify facilitating and hindering factors for the successful implementation of eLearning. Data collection took place between June and September 2016, when seven Maternal and Child Health (MNCH) related eLearning sessions were conducted. The participants were nurses and midwives working in MNCH wards at the research sites in Bamyan, Faizabad and Kandahar, along with the programme planners and facilitators. Data was collected through pre/post and delayed post-tests, observations and questionnaires, semi-structured interviews and documents analysis. The results highlight four major factors as important for the successful implementation of eLearning, namely: curriculum, context, technology and individual. The needs assessment ensured relevance of the sessions to the needs of the participants. However, pedagogy was lecture-based with limited focus on skills development. Poor connectivity and language of instruction posed challenges. eLearning has shown the potential for developing knowledge and skills of nurses and midwives. Clear communication between teams involved in planning and implementation of the programme, technology infrastructure, design of online pedagogy and facilitator readiness are critical for the success of eLearning in low and middle income countries.
Keywords: Health care providers/system, eLearning Programme, Nurses, Midwives, Maternal and child careHow to cite this article:Naseem, A., Ali, K.Q., Juma, A., Sajwani, A., Khan, B.A., Sayani, A. & Abidi, S.S.R. 2020. Factors enabling and hindering an eLearning programme for nurses and midwives in Afghanistan. Scholarship of Teaching and Learning in the South. 4(2): 80-99. https://doi.org/10.36615/sotls.v4i2.106.This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0
Validation Tools for Predicted Linear B-Epitopes: Surface Accessibility
No full textIdentifying B-cell epitopes plays an important role in vaccine design, immunodiagnostic tests, and antibody production. Therefore, computational tools for reliably predicting B-cell epitopes are highly desirable. In this article the possibility of usage of accessible surface scores of peptides as a validation tool is studied. Janin et al. determined empirical amino acid accessible surface probabilities of twenty amino acids. With these fractional surface probabilities for amino acids, a surface probability (S) at sequence position n can be found using a formula given by Emini et. al. When a peptide is uploaded to the Emini Surface Accessibility Prediction in iedb Analysis Resource, prediction tool separates residues into two groups buried, and surface according to the average of S_ns. To create a criterion to decide whether a given peptide is a linear b-epitope or not, for 344,121 b-epitopes downloaded from iedb database, average buried and exposed probabilities, as well as the ratio ρ of averages for these b-epitopes are computed. The same is done for 111,306 artificially created non epitopes. It is seen that for b-epitopes, the ratio ρ is significantly larger than the ratio ρ for the non epitopes. Therefore if ρ is larger, the peptide is more likely is a b-epitope, and this property can be used as to rank peptides while choosing the most probable linear b-epitope from a long list
Validation Tools for Predicted Linear B-Epitopes: Beta Turns
No full textIt is claimed that amino acid replacements in surface loops usually do not perturb the three-dimensional structure of the protein, since surface loops are relatively flexible (Saunders and Baker 2002). Thus, the conservation variability of epitopes might be biased by the abundance of loops in epitopes. These results imply that epitopes do not tend to overlap functional regions, but rather cover separate regions. Pellequera, et. al., (1993), developed new turn scales based on the occurrence of amino acids at each of the four positions of a turn using a structural database comprised of 87 proteins. It is found that the scales correctly predicted a fraction of the turn regions in proteins with approximately 80% confidence. They used the turn scales for predicting the location of antigenic sites in proteins. The method was developed with the specific aim of predicting only a few peaks for each protein. They found that it leads to a high level of accurate prediction around 70% of correct prediction of known epitopes. In this article we update turn scales using large numbers of proteins and epitopes. Improved method will be more helpful in selecting protein regions to be synthesized in order to produce anti-peptide antibodies cross-reacting with the parent protein
A Recurrent Neural Network Linear B-Epitope Predictor: BIRUNI
No full textExperimental methods used for characterizing epitopes that play a vital role in the development of peptide vaccines, in diagnosis of diseases, and also for allergy research are time consuming and need huge resources. There are many online epitope prediction tools are available that can help scientists in short listing the candidate peptides. To predict B-cell epitopes in an antigenic sequence, Jordan recurrent neural network (BIRUNI) is found to besuccessful. To train and test neural networks, 262.583 B epitopes are retrieved from IEDB database. 99.9% of these epitopes have lengths in the interval 6-25 amino acids. For each of these lengths, committees of 11 expert recurrent neural networks are trained. To train these experts alongside epitopes, non-epitopes are needed. Non-epitopes are created as random sequences of amino acids of the same length followed by a filtering process. To distinguish epitopes and non-epitopes, the votes of eleven experts are aggregated by majority vote. An overall accuracy of 97.23% is achieved. Then these experts are used to predict the Linear Bepitopes of five antigens, Plasmodium Falciparum, Human Polio Virus Sabin Strain, Meningitis, Plasmodium Vivax and Mycobacterium Tuberculosis. The success of BIRUNU is compared with the five online prediction tools ABCPRED, BCPRED, K&T, BEPIPRED, and AAP.It is seen that BIRUNI outperforms all of them in the average
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