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  1. Fulltext Stability, orientation and position preference of the stem region (residues 689-703) in Hepatitis C Virus (HCV) envelope glycoprotein E2: a molecular dynamics study
    Akbar R, Jusoh SA
    F1000Res, 2013;2:64.
    PMID: 24555044 DOI: 10.12688/f1000research.2-64.v2
    Envelope glycoproteins of Hepatitis C Virus (HCV) play an important role in the virus assembly and initial entry into host cells. Conserved charged residues of the E2 transmembrane (TM) domain were shown to be responsible for the heterodimerization with envelope glycoprotein E1. Despite intensive research on both envelope glycoproteins, the structural information is still not fully understood. Recent findings have revealed that the stem (ST) region of E2 also functions in the initial stage of the viral life cycle. We have previously shown the effect of the conserved charged residues on the TM helix monomer of E2. Here, we extended the model of the TM domain by adding the adjacent ST segment. Explicit molecular dynamics simulations were performed for the E2 amphiphilic segment of the ST region connected to the putative TM domain (residues 683-746). Structural conformation and behavior are studied and compared with the nuclear magnetic resonance (NMR)-derived segment of E2 ( 2KQZ.pdb). We observed that the central helix of the ST region (residues 689 - 703) remained stable as a helix in-plane to the lipid bilayer. Furthermore, the TM domain appeared to provide minimal contribution to the structural stability of the amphipathic region. This study also provides insight into the orientation and positional preferences of the ST segment with respect to the membrane lipid-water interface.
  2. Fulltext Molecular Dynamics Simulations of the Temperature Induced Unfolding of Crambin Follow the Arrhenius Equation
    Dalby A, Shamsir MS
    F1000Res, 2015;4:589.
    PMID: 26539292 DOI: 10.12688/f1000research.6831.1
    Molecular dynamics simulations have been used extensively to model the folding and unfolding of proteins. The rates of folding and unfolding should follow the Arrhenius equation over a limited range of temperatures. This study shows that molecular dynamic simulations of the unfolding of crambin between 500K and 560K do follow the Arrhenius equation. They also show that while there is a large amount of variation between the simulations the average values for the rate show a very high degree of correlation.
  3. Fulltext Visual acuity measured with luminance-modulated and contrast-modulated noise letter stimuli in young adults and adults above 50 years old
    Woi PJ, Kaur S, Waugh SJ, Hairol MI
    F1000Res, 2016;5:1961.
    PMID: 28184281 DOI: 10.12688/f1000research.9410.1
    The human visual system is sensitive in detecting objects that have different luminance level from their background, known as first-order or luminance-modulated (LM) stimuli. We are also able to detect objects that have the same mean luminance as their background, only differing in contrast (or other attributes). Such objects are known as second-order or contrast-modulated (CM), stimuli. CM stimuli are thought to be processed in higher visual areas compared to LM stimuli, and may be more susceptible to ageing. We compared visual acuities (VA) of five healthy older adults (54.0±1.83 years old) and five healthy younger adults (25.4±1.29 years old) with LM and CM letters under monocular and binocular viewing. For monocular viewing, age had no effect on VA [F(1, 8)= 2.50, p> 0.05]. However, there was a significant main effect of age on VA under binocular viewing [F(1, 8)= 5.67, p< 0.05].  Binocular VA with CM letters in younger adults was approximately two lines better than that in older adults. For LM, binocular summation ratios were similar for older (1.16±0.21) and younger (1.15±0.06) adults. For CM, younger adults had higher binocular summation ratio (1.39±0.08) compared to older adults (1.12±0.09). Binocular viewing improved VA with LM letters for both groups similarly. However, in older adults, binocular viewing did not improve VA with CM letters as much as in younger adults. This could reflect a decline of higher visual areas due to ageing process, most likely higher than V1, which may be missed if measured with luminance-based stimuli alone.
  4. Fulltext Molecular identification and phylogenetic analysis of GABA-producing lactic acid bacteria isolated from indigenous dadih of West Sumatera, Indonesia
    Anggraini L, Marlida Y, Wizna W, Jamsari J, Mirzah M, Adzitey F, et al.
    F1000Res, 2018 10 19;7:1663.
    PMID: 32201563 DOI: 10.12688/f1000research.16224.3
    Background: Dadih (fermented buffalo milk) is a traditional Indonesian food originating from West Sumatra province. The fermentation process is carried out by lactic acid bacteria (LAB), which are naturally present in buffalo milk.  Lactic acid bacteria have been reported as one of potential producers of γ-aminobutyric acid (GABA). GABA acts as a neurotransmitter inhibitor of the central nervous system. Methods: In this study, molecular identification and phylogenetic analysis of GABA producing LAB isolated from indigenous dadih of West Sumatera were determined. Identification of the GABA-producing LAB DS15 was based on conventional polymerase chain reaction. 16S rRNA gene sequence analysis was used to identify LAB DS15. Results: PCR of the 16S rRNA gene sequence of LAB DS15 gave an approximately 1400 bp amplicon.  Phylogenetic analysis showed that LAB DS15 was Pediococcusacidilactici, with high similarity of 99% at 100% query coverage to Pediococcusacidilactici strain DSM 20284. Conclusions: It can be concluded that GABA producing LAB isolated from indigenous dadih was Pediococcus acidilactici.
  5. Fulltext Peripheral refraction with different designs of progressive soft contact lenses in myopes
    Allinjawi K, Sharanjeet-Kaur SK, Akhir SM, Mutalib HA
    F1000Res, 2016;5:2742.
    PMID: 28163898 DOI: 10.12688/f1000research.9971.1
    Aim: The purpose of this study was to compare the changes in relative peripheral refractive error produced by two different designs of progressive soft contact lenses in myopic schoolchildren. Methods: Twenty-seven myopic schoolchildren age between 13 to 15 years were included in this study. The measurements of central and peripheral refraction were made using a Grand-Seiko WR-5100K open-field autorefractometer without correction (baseline), and two different designs of progressive contact lenses (PCLs) (Multistage from SEED & Proclear from Cooper Vision) with an addition power of +1.50 D. Refractive power was measured at center and at eccentricities between 35º temporal to 35º nasal visual field (in 5º steps). Results: Both PCLs showed a reduction in hyperopic defocus at periphery. However, this reduction was only significant for the Multistage PCL (p= 0.015), (Proclear PCL p= 0.830).  Conclusion: Multistage PCLs showed greater reduction in peripheral retinal hyperopic defocus among myopic schoolchildren in comparison to Proclear PCLs.
  6. Fulltext Coping strategies of students for anxiety during the COVID-19 pandemic in China: a cross-sectional study
    Nurunnabi M, Hossain SFAH, Chinna K, Sundarasen S, Khoshaim HB, Kamaludin K, et al.
    F1000Res, 2020;9:1115.
    PMID: 33274049 DOI: 10.12688/f1000research.25557.1
    Background: COVID-19 has severely affected university students everywhere in the world. Due to fear of infection, government and local authorities in China immediately closed academic institutions and tried to find survival techniques to cope with market turbulence. COVID-19 was present in China at the end of 2019. However, little attention has been paid by researchers to coping strategies during the COVID-19 pandemic, and few measures were taken to assess the coping strategies of university students, specifically following the closure of their institutions. To address this gap, this study attempted to discover the coping strategies of Chinese students during the COVID-19 pandemic in China. Methods: We conducted an online survey using a semi-structured questionnaire with a simple random sampling technique and received 559 responses. The survey questions captured information about students' lives during the COVID-19 outbreak, actions to control anxiety, and what students care about during the pandemic. The associations between coping strategies used and levels of anxiety were tested using analysis of variance (ANOVA) procedures. SPSS Statistics v27 was used for statistical analysis in this study. Results: The university students reported that coping strategies and survival techniques were required due to high levels of anxiety and psychological pressure during the COVID-19 pandemic. Most of the respondents reported the prompt closure of their academic institutions due to COVID-19. Psychological concerns, such as lack of sleep, emotional support, mental support and social appeal, were also reported. Conclusions: This is one of the very first studies on coping strategies for anxiety in China. The study reveals that university students employ a number of coping strategies in relation to COVID-19, but also suggests a need to strengthen such strategies in this population. However, the study was limited to a small number of provinces in China, which may affect the generalizability of the research.
  7. Fulltext Phytochemical, antioxidant and antimicrobial properties of Litsea angulata extracts
    Kuspradini H, Wulandari I, Putri AS, Tiya SY, Kusuma IW
    F1000Res, 2018;7:1839.
    PMID: 30774930 DOI: 10.12688/f1000research.16620.2
    Background:Litsea angulata is a plant species belonging to Lauraceae family that is distributed throughout Indonesia, Malaysia, and New Guinea. The seeds have been traditionally used by local people in Kalimantan, Indonesia for the treatment of boils; however, there is no information about the potency of its branch, bark and leaves yet. This study aimed to determine the antioxidant, antimicrobial activity as well as the phytochemical constituent of Litsea angulata branch, bark, and leaves. Methods: Extraction was performed by successive maceration method using n-hexane, ethyl acetate, and ethanol solvent. Antioxidant activity was evaluated by DPPH radical scavenging assay. The antimicrobial activity using the 96 well-plate microdilution broth method against Staphylococcus aureus and Streptococcus mutans. Results: Based on the phytochemical analysis, it showed that extract of L. angulata contains alkaloids, flavonoids, tannins, terpenoids, and coumarin. The results showed that all extracts of plant samples displayed the ability to inhibit DPPH free radical formation and all tested microorganisms. Conclusions:L. angulata contains secondary metabolites such as alkaloids, flavonoids, tannins, terpenoids, carotenoids, and coumarin. The antioxidant activity on different plant extracts was a range as very strong to weak capacity. All extracts in this study could inhibit the growth of S. aureus and S. mutans.
  8. Fulltext Development of species-specific SCAR markers for identification and authentication of three rare Peninsular Malaysian endemic Coelogyne (Orchidaceae) orchids
    Kok Hon Y, Yong CS, Abdullah JO, Go R
    F1000Res, 2020;9:1161.
    PMID: 33299554 DOI: 10.12688/f1000research.26170.2
    Background:Coelogyne kaliana, Coelogyne stenochila and Coelogyne tiomanensis are three valuable rare orchid species endemic to Peninsular Malaysia, currently rampantly traded illegally via the internet and through local nurseries, which label them as hybrids to avoid enforcement detection. Drastic measures to ensure the continued existence of their populations in the wild should be introduced as they are rapidly diminishing into extinction, including the development of rapid and accurate species-specific identification tools. These three orchid species are highly similar morphologically and currently it is impossible to distinguish among them without their reproductive structures. Methods:  RAPD-based species-specific SCAR markers were developed to distinguish and authenticate the identity of these three endemic Peninsular Malaysian Coelogyne species. Results: Three SCAR markers were successfully developed in this study. SCAR marker primer pair , CKL_f / CKL_r was specific to C. kaliana as it produced a unique single band of 271 bp but not in C. stenochila and C. tiomanensis.  SCAR marker primer pair CST_f / CST_r amplified a single band of 854 bp in C. stenochila and two bands of different sizes (372 bp and 858 bp) in C. tiomanensis, but no amplification in C. kaliana. The third SCAR marker primer pair, CTI_f / CTI_r produced a single band (about 500 bp) for both C. stenochila and C. tiomanensis, but showed no amplification in C. kaliana. Conclusions: Although not all these SCAR markers were species amplification specific, they could be used to discriminate among the three Coelogyne species effectively.  Accurate species identification is one of the most important steps to allow a proper management plan to be established in the effort to conserve these three endangered orchid species of Peninsular Malaysia. Besides, it could effectively put a stop to the illegal trading of these rare endangered orchid species worldwide.
  9. Fulltext Lifestyle and reproductive health: the aetiology of ovarian cancer in Pakistan
    Alvi Q, Baloch GM, Chinna K, Dabbagh A
    F1000Res, 2020;9:901.
    PMID: 32802322 DOI: 10.12688/f1000research.24866.1
    Ovarian cancer is a fatal gynaecological cancer and eighth most common cancer in women globally. Lifestyle, reproductive and sociodemographic factors are among the influential parameters that may significantly affect the risk of ovarian cancer and its mortality rate. However, the epidemiological investigations have shown that the risk of ovarian cancers associated with these factors is different in varied geographical distributions. Lifestyle and reproductive factors have not been investigated thoroughly across a wide cultural diversity. The objective of this study is to investigate the association of these factors with ovarian cancer in Pakistan. This investigation will focus on the lifestyle effects of fat intake, intake of tea, habitual exercise, use of talc, personal hygiene, habit of holding urine for long time, obesity on ovarian cancer among Pakistani women.  Reproductive variables will include age at menarche, natural menopausal age, parity, nulliparity (miscarriages, abortion, stillbirths), infertility, fertility treatment, tubal ligation, oral contraceptive use, and family history of breast or ovarian cancer. Sociodemographic variables will include effect of age, income, education, and geographical location. A case-control study will be conducted in the major cancer hospitals of Pakistan and the patients will also be interviewed. The controls will be recruited outside the hospital. For controls the same age limit and residency requirements will be applied. The information gained from this research will be an important contribution to develop programs for health promotion, with a focus on ovarian cancer prevention and women's health. The findings could be used for health policies and planning to prevent ovarian cancer. The research will pave the way for a public policy and interventions to reduce the burden of ovarian cancer in Pakistan.
  10. Fulltext A retrospective review on minimally invasive technique via endoscopic thoracic sympathectomy (ETS) in the treatment of severe primary hyperhidrosis: Experiences from the National Heart Institute, Malaysia
    Musa AF, Gandhi VP, Dillon J, Nordin RB
    F1000Res, 2018;7:670.
    PMID: 32724556 DOI: 10.12688/f1000research.14777.1
    Background: Hyperhidrosis is due to the hyperactive autonomic stimulation of the sweat glands in response to stress. Primary hyperhidrosis is a common yet psychologically disabling condition. This study will describe our experience in managing hyperhidrosis via endoscopic thoracic sympathectomy (ETS). Methods: The information was obtained from the patient records from 1 st January 2011 until 31 st December 2016. Pertinent information was extracted and keyed into a study proforma. Results:  150 patients were operated on but only 118 patients were included in this study. The mean age was 22.9±7.3 years. The majority (54.2%) had palmar-plantar hyperhidrosis and 39.8% had associated axillary hyperhidrosis. Excision of the sympathetic nerve chain and ganglia were the main surgical technique with the majority (55.9%) at T2-T3 level. Mean ETS procedure time was 46.6±14.29 minutes with no conversion. Surgical complications were minimal and no Horner's Syndrome reported. Mean hospital stay was 3.5±1.05 days. The majority of patients (67.8%) had only one follow-up and only half of the study sample (58.5%) complained mild to moderate degree of compensatory sweating, even though the long-term resolution is yet to be determined by another study. Following ETS, 98.3% of patients had instant relief and resolved their palmar hyperhidrosis. Predictors of CS were sympathectomy level and follow-up. The odds of reporting CS was 2.87 times in patients undergoing ETS at the T2-T3 level compared to those undergoing ETS at the T2-T4 level. The odds of reporting CS was 13.56 times in patients having more than one follow-up compared to those having only one follow-up. Conclusion: We conclude that ETS is a safe, effective and aesthetically remarkable procedure for the treatment of primary hyperhidrosis  with only half of the patients developing mild to moderate degree of CS. Significant predictors of CS were sympathectomy level during ETS and frequency of follow-up after ETS.
  11. Fulltext Relationship and career challenges faced by people infected with HIV in Malaysia
    Tuan Abdullah TN, Mat Min R, Hossain M, Abdullah SS
    F1000Res, 2019;8:1994.
    PMID: 33214871 DOI: 10.12688/f1000research.21079.3
    Background: In Malaysia, there are still lack of studies  related to the challenges of people infected with HIV (PIWH). Therefore, this study was conducted to explore the experiences of PIWH and how they cope with HIV. Methods: This qualitative study was based on a social constructivist and grounded theory approach. A total of 12 PIWH were selected by purposive sampling, all of whom participated in semi-structured and audio-recorded interviews, which were supported with non-participant observations and diary entries on three occasions for each participant. The interviews and diaries were transcribed and analysed using the grounded theory approach, which was assisted by utilizing NVIVO-8 to identify the themes related to the experiences of the participants. Results: PIWH experienced challenges related to their career and relationships with family and others. These challenges led to difficulties in gaining employment and career development, as well as feelings of denial, being uncomfortable, rejection, and labelling. They found that their lives were totally and dramatically changed after being tested positive for HIV. Conclusions: Among PIWH, HIV impacted relationships with significant others and career development. The absence of support and acceptance from significant others affected the ability of PIWH to cope with their daily challenges. The results of this study have implications for policymakers in terms of gaining sufficient knowledge and awareness to provide prevention programmes for HIV/AIDS.
  12. Fulltext Correlation between salivary estrogen levels and oral epithelial cytokeratin 5 expression
    Handajani J, Effendi N, Sosroseno W
    F1000Res, 2020;9:186.
    PMID: 32399205 DOI: 10.12688/f1000research.22536.2
    Background: Estrogen expression levels may be associated with age and may affect keratinization of the hard palate. Keratinized epithelium expresses cytokeratin 5 and 14 in the basal layer. The aim of this study was to determine the correlation between the levels of salivary estrogen and number of cytokeratin 5-positive oral epithelial cells. Methods: A total of 30 female subjects were recruited and divided into children, adults and elderly (N=10 per group). Salivary estrogen levels and cytokeratin 5-expressing oral epithelial cells were assessed using ELISA and immunohistological methods, respectively. Data were analyzed using ANOVA with post hoc LSD test and Pearson's correlation coefficient. Results: The results showed that both the number of cytokeratin 5-positive cells and the level of salivary estrogen were significantly higher in adults but decreased in the elderly, as compared with those in children (p<0.05). Furthermore, the levels of salivary estrogen were significantly correlated with the number of cytokeratin 5-positive cells (r=0.815). The ANOVA result showed significance difference cytokeratin 5 expression and estrogen level (p<0.05). The post hoc LSD test revealed cytokeratin 5 expression and estrogen level to be significantly different in children, adults, and elderly participants (p<0.05). Conclusions: These results suggest that the profile of salivary estrogen and oral epithelial cell-expressed cytokeratin 5 may be positively correlated with age and depend on age.
  13. Fulltext A simple optical pH sensor based on pectin and Ruellia tuberosa L-derived anthocyanin for fish freshness monitoring
    Nazaruddin N, Afifah N, Bahi M, Susilawati S, Sani NDM, Esmaeili C, et al.
    F1000Res, 2021;10:422.
    PMID: 34527216 DOI: 10.12688/f1000research.52836.2
    A simple optical pH sensor using the active compound anthocyanin (ACN), derived Ruellia tuberosa L. flower immobilized in a pectin membrane matrix, was been fabricated and employed to monitor the freshness of tilapia fish at room temperature and 4 oC storage. The quantitative pH values were measured based on the UV-Vis spectroscopy absorbance. The optimum pectin weight and ACN concentrations were 0.1% and 0.025 mg/L. The sensor showed good sensitivity at 0.03 M phosphate buffer solution. The sensor's reproducibility was evaluated using 10 replicate sensors where a standard deviation of 0.045 or relative standard deviation of 9.15 was achieved. The sensor displayed an excellent response after 10 minutes of exposure, possessing a response stability for 10 consecutive days. The decrease in pH value of the Tilapia fish from 7.3 to 5 was observed in a 48 hour test, which can be used as the parameter when monitoring fish freshness. Overall, this reported optical pH sensor has a novelty as it could be used to monitor the rigor mortis phase of fish meat, which is useful in food industry.
  14. Fulltext Cardiovascular involvement and manifestations of systemic Chikungunya virus infection: A systematic review
    Alvarez MF, Bolívar-Mejía A, Rodriguez-Morales AJ, Ramirez-Vallejo E
    F1000Res, 2017;6:390.
    PMID: 28503297 DOI: 10.12688/f1000research.11078.2
    BACKGROUND: In the last three years, chikungunya virus disease has been spreading, affecting particularly the Americas, producing more than two million cases. In this setting, not only new disease-related epidemiological patterns have been found, but also new clinical findings have been reported by different research groups. These include findings on the cardiovascular system, including clinical, electrocardiographic and echocardiographic alterations. No previous systemic reviews have been found in major databases about it.

    METHODS: We performed a systematic review looking for reports about cardiovascular compromise during chikungunya disease. Cardiac compromise is not so common in isolated episodes; but countries where chikungunya virus is an epidemic should be well informed about this condition. We used 6 bibliographical databases as resources: Medline/Pubmed, Embase, ScienceDirect, ClinicalKey, Ovid and SciELO. Dengue reports on cardiovascular compromise were included as well, to compare both arbovirus' organic compromises. Articles that delved mainly into the rheumatic articular and cutaneous complications were not considered, as they were not in line with the purpose of this study. The type of articles included were reviews, meta-analyses, case-controls, cohort studies, case reports and case series. This systematic review does not reach or performed a meta-analysis.

    RESULTS: Originally based on 737 articles, our reviewed selected 40 articles with 54.2% at least mentioning CHIKV cardiovascular compromise within the systemic compromise. Cardiovascular manifestations can be considered common and have been reported in France, India, Sri Lanka, Malaysia, Colombia, Venezuela and USA, including mainly, but no limited to: hypotension, shock and circulatory collapse, Raynaud phenomenon, arrhythmias, murmurs, myocarditis, dilated cardiomyopathy, congestive insufficiency, heart failure and altered function profile (Troponins, CPK).

    CONCLUSIONS: Physicians should be encouraged to keep divulgating reports on the cardiovascular involvement of chikungunya virus disease, to raise awareness and ultimately encourage suitable diagnosis and intervention worldwide. More research about cardiovascular involvement and manifestations of systemic Chikungunya virus infection is urgently needed.

  15. Fulltext Assessing the species composition of tropical eels (Anguillidae) in Aceh Waters, Indonesia, with DNA barcoding gene cox1
    Muchlisin ZA, Batubara AS, Fadli N, Muhammadar AA, Utami AI, Farhana N, et al.
    F1000Res, 2017;6:258.
    PMID: 28529702 DOI: 10.12688/f1000research.10715.1
    The objective of the present study was to evaluate the species diversity of eels native to Aceh waters based on genetic data. Sampling was conducted in western coast waters of Aceh Province, Indonesia, from July to August 2016. Genomic DNA was extracted from the samples, a genomic region from the 5' region of the cox1 gene was amplified and sequenced, and this was then used to analyse genetic variation. The genetic sequences were blasted into the NCBI database. Based on this analysis there were three valid species of eels that occurred in Aceh waters, namely Anguilla marmorata, A. bicolor bicolor, and A. bengalensis bengalensis.
  16. Fulltext The challenges of designing a benchmark strategy for bioinformatics pipelines in the identification of antimicrobial resistance determinants using next generation sequencing technologies
    Angers-Loustau A, Petrillo M, Bengtsson-Palme J, Berendonk T, Blais B, Chan KG, et al.
    F1000Res, 2018;7.
    PMID: 30026930 DOI: 10.12688/f1000research.14509.2
    Next-Generation Sequencing (NGS) technologies are expected to play a crucial role in the surveillance of infectious diseases, with their unprecedented capabilities for the characterisation of genetic information underlying the virulence and antimicrobial resistance (AMR) properties of microorganisms.  In the implementation of any novel technology for regulatory purposes, important considerations such as harmonisation, validation and quality assurance need to be addressed.  NGS technologies pose unique challenges in these regards, in part due to their reliance on bioinformatics for the processing and proper interpretation of the data produced.  Well-designed benchmark resources are thus needed to evaluate, validate and ensure continued quality control over the bioinformatics component of the process.  This concept was explored as part of a workshop on "Next-generation sequencing technologies and antimicrobial resistance" held October 4-5 2017.   Challenges involved in the development of such a benchmark resource, with a specific focus on identifying the molecular determinants of AMR, were identified. For each of the challenges, sets of unsolved questions that will need to be tackled for them to be properly addressed were compiled. These take into consideration the requirement for monitoring of AMR bacteria in humans, animals, food and the environment, which is aligned with the principles of a "One Health" approach.
  17. Fulltext The protective effects of antigen-specific IgY on pyocyanin-treated human lymphoma Raji cells
    Susilowati H, Artanto S, Yulianto HDK, Sosroseno W, Hutomo S
    F1000Res, 2019;8:1008.
    PMID: 32025288 DOI: 10.12688/f1000research.19327.2
    Background: Pyocyanin (PCN), a highly pathogenic pigment produced by Pseudomonas aeruginosa, induces caspase 3-dependent human B cell (Raji cells) death. The aim of the present study, therefore, was to assess whether antigen-specific IgY antibodies may be protective on PCN-induced Raji cell death. Methods: Chickens were subcutaneously immunized with Freund's complete adjuvant containing PCN, and then given two boosted immunizations.  Anti-PCN IgY antibodies were purified from egg yolk and detected using an agar gel precipitation test (AGPT) and ELISA. Protective effects of antigen-specific IgY on Raji cells were tested using a cell viability assay. Results: AGPT results showed the formation of strong immune complex precipitates, whilst ELISA further confirmed the presence of IgY antibodies specific to PCN at significant concentration. Further experiments showed that anti-PCN IgY antibodies significantly increased PCN-treated Raji cell viability in a dose-dependent fashion (p<0.05). Conclusions: The results of the present study suggest that anti-PCN IgY antibodies may be protective on PCN-induced Raji cell death.
  18. Fulltext Design for learning - a case study of blended learning in a science unit
    Gleadow R, Macfarlan B, Honeydew M
    F1000Res, 2015;4:898.
    PMID: 26594348 DOI: 10.12688/f1000research.7032.2
    Making material available through learning management systems is standard practice in most universities, but this is generally seen as an adjunct to the 'real' teaching, that takes place in face-to-face classes. Lecture attendance is poor, and it is becoming increasingly difficult to engage students, both in the material being taught and campus life. This paper describes the redevelopment of a large course in scientific practice and communication that is compulsory for all science students studying at our Melbourne and Malaysian campuses, or by distance education. Working with an educational designer, a blended learning methodology was developed, converting the environment provided by the learning management system into a teaching space, rather than a filing system. To ensure focus, topics are clustered into themes with a 'question of the week', a pre-class stimulus and follow up activities. The content of the course did not change, but by restructuring the delivery using educationally relevant design techniques, the content was contextualised resulting in an integrated learning experience. Students are more engaged intellectually, and lecture attendance has improved. The approach we describe here is a simple and effective approach to bringing this university's teaching and learning into the 21 (st) century.
  19. Fulltext Technology readiness and UTAUT2 in e-wallet adoption in a developing country
    Leong MY, Kwan JH, Ming Ming L
    F1000Res, 2021;10:863.
    PMID: 34621517 DOI: 10.12688/f1000research.72853.1
    Background: An e-wallet is a digital equivalent of a physical wallet which plays an essential role in payment system transformation. To embrace the concept of a cashless society, the Malaysian Government and central bank have taken various steps to encourage the adoption of e-wallets. Despite the seamless services offered by the e-wallet, it is yet to reach high-scale adoption in Malaysia. This study aims to investigate Malaysians' readiness towards the e-wallet and their perceptions of it by employing the UTAUT2 model. Methods: A total of 309 valid data were gathered and analysed with partial least squares structural equation modelling (PLS-SEM). Results: The findings revealed that the respondents were confident about the new technology and tended to believe that e-wallet was somehow useful for them. The results also disclosed that e-wallet adoption intention was significantly influenced by performance expectancy, price value, facilitating conditions, and followed closely by social influence. Nonetheless, insecurity did not present significant impact on both performance expectancy and effort expectancy of e-wallet. Conclusions: This study provides a substantial contribution to the knowledge domain by combining system-specific and individual-specific models in an e-wallet context. The outcomes of this study would also benefit e-wallet service providers and policymakers by delivering holistic insight into Malaysians' readiness and adoption behaviour of the e-wallet.
  20. Fulltext Kyasanur forest disease virus: viremia and challenge studies in monkeys with evidence of cross-protection by Langat virus infection
    Shah KV, Dandawate CN, Bhatt PN
    F1000Res, 2012;1:61.
    PMID: 24627765 DOI: 10.12688/f1000research.1-61.v1
    Kyasanur Forest Disease Virus (KFDV), discovered in 1957, is a member of the tick-borne encephalitis virus (TBEV) complex. Diseases caused by members of the TBEV complex occur in many parts of the world. KFDV produces a hemorrhagic fever in humans in South India and fatal illnesses in both species of monkeys in the area, the black faced langur (Presbytis entellus) and the bonnet macaque (Macaca radiata). Experimental infection of the langur and the bonnet macaque with early mouse passage KFDV strain P9605 resulted in a viremia of up to 11 days duration, peak viremia titers as high as 10 (9), and death in 82 = 100% of the animals. Prolonged passage of the KFDV strain P9605 in monkey kidney tissue culture resulted in a markedly reduced virulence of the virus for both species; peak viremia titers in monkeys decreased by 2.5 to 4.0 log LD 50 (p= 0.001), and the mortality decreased to 10% (p= 0.001). In challenge experiments, monkeys previously infected with tissue-culture-adapted KFDV, or with the related Langat virus from Malaysia, were fully protected against virulent KFDV. These studies in non-human primates lend support to the idea that a live virus vaccine from a member of the TBEV complex may be broadly protective against infections by other members of the TBEV complex.
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