Regulation of hypoxia responsive gene expression by specificity protein family transcription factors in breast cancer

Cancer accounts for the highest amounts of disease related premature deaths worldwide with 8.1 million of deaths being associated with malignancy. In the cancer microenvironment, particularly in solid tumours, hypoxia plays a significant role in progression and metastasis by altering signal transduction and gene regulation which leads to aggressive phenotypes, poor prognosis and lower survival rates. Hypoxia-Inducible Factor (HIF) driven gene regulation is well established and believed to promote survival of tumour cells under the hypoxic microenvironment. Accumulating evidence also suggests that Specificity protein (Sp) family transcription factors might also play a role in the hypoxic microenvironment by regulating transcription of key hypoxia responsive genes such as VEGFA in either a HIF dependent or independent manner. In normal cells, Sp transcription factors are ubiquitously expressed and known to regulate numerous genes involved in vital cellular pathways such as cell cycle, apoptosis and angiogenesis. In tumour environments, deregulated Sp protein levels have been demonstrated and shown to correlate with poor prognosis and treatment response. However, the exact role of Sp transcription factors in hypoxic microenvironment is not fully understood.This study aimed to identify the effect of severe (chronic) hypoxia on Sp transcription factors and hypoxia-responsive gene regulation using breast cancer as a cell model. Initial studies measured the expression levels and binding activity of Sp transcription factors. Subsequently, an integrative genomic analysis was performed to identify Sp driven hypoxia-responsive genes in breast cancer cells. The study was further extended to analyse the binding kinetics of Sp protein inhibitors using surface plasmon resonance spectroscopy. Finally, transcriptional changes of hypoxia responsive genes were examined after addition of Sp inhibitors or knockdown of Sp1 level under the hypoxic environment.Expression analysis of Sp family members (Sp1-4) showed that the transcript levels of Sp genes were unaffected due to chronic hypoxic exposure whilst Sp protein levels were induced in all three cell lines. However, expression patterns were dependent on tissue type and severity of hypoxia. Twenty genes were identified as potential Sp driven hypoxia responsive genes which are consist of GC-rich putative Sp binding sites in their promoters. Gene expression analysis validated the hypoxic induction of these genes and their dependency on Sp protein-mediated transcription. Affinity studies of Sp protein inhibitors prove binding of antibiotic derivatives, Mithramycin A and Chromomycin A to GC-rich regions with different binding affinities and kinetics. Different Equilibrium constants (Kd) of Mithramycin A and Chromomycin A were identified which varied according to the promoter sites (10⁻³ to 10⁻⁶ M range). Furthermore, novel data also confirm the Mithramycin-DNA interaction is independent of cation Mg²⁺ which has been considered obligatory for DNA interaction. Interestingly, nordihydroguaiaretic acid (NDGA) derivative, Terameprocol exhibits no detectable interaction with linear DNA consisting of Sp binding sites.These results emphasise the importance of Sp proteins as regulators of hypoxia-mediated gene transcription. Sp-regulated transcription is vital in altering hypoxia-related cellular pathways and has a potential as biomarkers for solid tumours. Moreover, these results suggest the potential use of Sp antagonists to inhibit expression of key hypoxic genes in the cancer microenvironment. Results also provide solid background knowledge on pharmacokinetics of Sp inhibitors which will be useful in synthesis of new derivatives which can be used in novel therapeutic strategies for cancer and perhaps other diseases. Understanding the molecular mechanisms of Sp mediated hypoxic gene regulation can be further extended to elucidate other cellular stress and cellular adaptive mechanism

Group Support Systems (GSS)

Groupware is a term describing an emerging computer software technology enhancing the ability of people to work together as a group, (a software driven 'group support system'). This project originated at the beginning of 1992 and reports were issued describing the activity through May 1995. These reports stressed the need for process as well as technology. That is, while the technology represented a computer assisted method for groups to work together, the Group Support System (GSS) technology als required an understanding of the facilitation process electronic meetings demand. Even people trained in traditional facilitation techniques did not necessarily aimlessly adopt groupware techniques. The latest phase of this activity attempted to (1) improve the facilitation process by developing training support for a portable groupware computer system, and (2) to explore settings and uses for the portable groupware system using different software, such as Lotus Notes

Assisting Professional Development of Subordinate Engineers; Evidence from Owner/Manager Entrepreneurial Engineers in Sri Lanka

Many innovative-minded engineers have stepped towards the business domain as entrepreneurs in the international context and in the Sri Lankan context. Most entrepreneurial engineers have exploited technology-related business opportunities and succeeded in their entrepreneurial journey while contributing immensely to the economic development of the country. Although these engineers play the role of a business leader, they are professionally qualified engineers. Hence, they cannot neglect Engineering Ethics and perform as pure business managers in their entrepreneurial firms. The Code of Engineering Ethics applicable to Sri Lanka advises local engineers to actively assist and encourage the subordinate engineers to advance knowledge and experience. Therefore, Sri Lankan entrepreneurial engineers have an ethical responsibility to support the professional development of subordinate engineers. Both fields of entrepreneurship and ethics of engineers lack systematic studies in Sri Lanka. Thus, the authors were involved in an ongoing grounded theory-based qualitative study on entrepreneurial engineers' ethical practices in Sri Lanka. Based on the findings of that study, this paper investigates the strategies followed by Sri Lankan owner/manager entrepreneurial engineers on the professional development of their subordinate engineers. A purposively and theoretically selected sample of twelve entrepreneurial engineers was interviewed face to face to collect data. Interviews were voice recorded and transcribed verbatim. Interview transcripts were analyzed employing grounded theory techniques to achieve this study's objective with the NVivo software's support. The study reveals that Engineering Ethics' influence has compelled entrepreneurial engineers to follow various employee development strategies. As highlighted in their interviews, training, teaching, coaching & mentoring are the major categories of procedures followed by entrepreneurial engineers in Sri Lanka. This study's findings can be considered as guidance for emerging and future entrepreneurial engineers to create a mutually beneficial sustainable work environment for entrepreneurial engineers and their employees while achieving business success.          KEYWORDS:     Entrepreneurial Engineers, Professional Development, Sri Lanka, Subordinates &nbsp

Correlated Quantum Transport of Density Wave Electrons

Recently observed Aharonov-Bohm quantum interference of period h/2e in charge density wave rings strongly suggest that correlated density wave electron transport is a cooperative quantum phenomenon. The picture discussed here posits that quantum solitons nucleate and transport current above a Coulomb blockade threshold field. We propose a field-dependent tunneling matrix element and use the Schrodinger equation, viewed as an emergent classical equation as in Feynman's treatment of Josephson tunneling, to compute the evolving macrostate amplitudes, finding excellent quantitative agreement with voltage oscillations and current-voltage characteristics in NbSe3. A proposed phase diagram shows the conditions favoring soliton nucleation versus classical depinning. (Published in Phys. Rev. Lett. 108, 036404 (2012).)Comment: 9 pages, 4 figures, (5 pages & 3 figures for main article), includes Supplemental Material with 1 figure. Published version: Physical Review Letters, vol. 108, p. 036404 (2012

Habitat Selection of the Grey Slender Loris (Loris lydekkerianus) in the Popham’s Arboretum, Dambulla, Sri Lanka

The Popham’s Arboretum, a small regenerated forest patch located in a highly urbanized setting in Dambulla, is home to a small population of the Grey Slender Loris (Loris lydekkerianus). Here we report on the habitat selection of the Grey Slender Loris within the arboretum. Nocturnal surveys were conducted on 20 days during three sampling sessions between September 2016 to June 2017. The majority of the 55 loris sightings made during the survey period were concentrated within the core areas of the forest. These sightings were geo-referenced and marked for habitat sampling. A total of twenty 10x10 m quadrates centered on these sightings (n=13) and additional quadrates located where no sightings were made during the survey (n=7), were used for the habitat analyses. Six habitat parameters previously shown to be important for the loris; % canopy cover, mean DBH, total abundance of plants over 10 cm GBH, species richness of plants, number of creepers and the distance to the forest edge were recorded for each quadrate. Further, temperature and relative humidity within each of the quadrates were also recorded between 1900 and 1800 hrs. Results indicate a significant differences in four of these parameters (species richness of trees, canopy cover, distance to the forest boundary and relative humidity) between areas of the forest that were used and those that were not used by the loris (p<0.05). Interestingly, the PC1 and PC2 explaining approximately 60 % of the variation in the habitat (derived from PCA analyses) indicates that microhabitat features within used areas were different to those that were not used. Two plant species, the creeper Derris parviflora (Kala Wel) and the tree Diplodiscus verrucosus (Dikwanna), showed up as species that were preferentially used by the loris as indicated by the Selectivity Index, where the percentage usage far exceeded their percentage availability within the forest (% availability and % usage values were 5.19 and 27.3 for D. parviflora and 11.58 and 29.0 for D. verrucosus). The preference for areas with the creeper might be explained by the fact that it eases climbing and movement of the loris. However, no explanation could be given at this stage for its preference for the D. verrucosus tree. The findings nevertheless suggest that enrichment with preferred plants could be used to increase habitat utilization by the loris, which would be critical to ensure their survival in small and isolated forest fragments in the dry zone of Sri Lanka. Keywords: Dry zone forest, Habitat selection, Lori

Clinical trial of a low-cost external fixator for global surgery use

PURPOSE: A low-cost modular external fixator for the lower limb has been developed for global surgery use. The purpose of this study is to assess outcome measures in the first clinical use of the device. METHODS: A prospective cohort study was conducted with patients recruited in two trauma hospitals. Initial clinical procedure data were collected, and patients were followed up every two weeks until 12 weeks or definitive fixation. Follow-up assessed infection, stability, and radiographic outcomes. In addition, patient-reported outcomes and surgeons' feedback on device usability were collected by questionnaires. RESULTS: The external fixator was used on 17 patients. Ten were mono-lateral, five were joint spanning, and two were delta configuration. One patient had a pin site infection at 12-week follow-up. All were stable when tested mechanically and using radiographic assessment, and 53% were converted to definitive fixation. CONCLUSION: The low-cost external fixator developed is appropriate for use in global surgery trauma centres with good clinical outcomes. PROSPECTIVE TRIAL REGISTRATION NUMBER AND DATE: SLCTR/2021/025 (06 Sep 2021)

Bacterial pathogens in conjunctivitis and corneal ulcers with special reference to Streptococcus pneumoniae, in early 2008, in the National Eye Hospital, Sri Lanka

Introduction: The most important and frequently occurring eye infections are conjunctivitis and corneal ulcers. Though the significance of Streptococcus pneumoniae in eye infections is well-known, identification of causative serotypes is important for comparison with serotypes causing invasive diseases. Objectives: To describe the spectrum and characteristics of bacterial pathogens associated with conjunctivitis and corneal ulcers with special reference to S. pneumoniae.Methods: A descriptive cross-sectional study was carried out from January to April 2008 in which samples were collected from patients above one month old with suspected conjunctivitis or corneal ulcers seen in the out-patients department and wards of the National Eye Hospital, Colombo, Sri Lanka. Both eye swabs (n=322) and corneal buttons (n=31) were cultured. Isolated bacteriawere identified as far as possible and antibiotic sensitivity testing done. S. pneumoniae isolates were stored in sheep blood agar slants at -70 ºC and serotyped. Results: There were 296 conjunctival swabs and 26 corneal swabs. From 296 conjunctival swabs 118 (39.8%) samples yielded no bacterial growth. There were 185 bacterial isolates from 159 significant positive samples. The most frequently isolated bacteria were coagulase negative Staphylococcus sp. (n=58: 31.4%), and second commonest was S. pneumoniae (n=33: 17.84%). From 57 samples from patients with corneal ulcers, 47 (82%) did not yield any bacterial growth. Sensitivity to chloramphenicol was high among Staphylococcus sp., S. pneumoniae, Haemophilus influenzae, Moraxella sp and coliforms. Among pneumococcal isolates serotyped, 19F was predominant. Conclusion: Coagulase negative staphylococci were predominantly isolated from eye swabs and corneal buttons, but the most significant frequent isolate was S. pneumoniae. Except Pseudomonas, &gt;90% isolates were sensitive to chloramphenicol. The predominant pneumococcal serotype was 19F.</p