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Fulltext Determining the impact of pre-lecture educational video on comprehension of a difficult gross anatomy lecture

Hadie SNH, Simok AA, Shamsuddin SA, Mohammad JA

J Taibah Univ Med Sci, 2019 Aug;14(4):395-401.
PMID: 31488974 DOI: 10.1016/j.jtumed.2019.06.008

Objective: Students commonly perceive gross anatomy lectures as difficult because they contain complex information that requires three-dimensional visualisation in order to be understood. Without prior preparation, a gross anatomy topic expounded via lecture can be cognitively challenging. Hence, this study aimed to investigate the impact of a pre-lecture activity in the form of viewing a video on students' lecture comprehension.
Method: A quasi-experimental study was conducted using 254 first-year medical students with no prior exposure to the lecture topic during the 2016/17 and 2017/18 academic sessions. The students from each batch were divided into two groups and exposed to different video material. Group A watched an action movie, while Group B watched an educational video related to the lecture topic. After 15 min, both groups attended a lecture on the gross anatomy of the heart, which was delivered by a qualified anatomist. At the end of the lecture, their understanding of the material was measured through a post-lecture test using ten vetted multiple choice true/false questions.
Results: Group B's test scores were found to be significantly higher than Group A's (p > 0.001, t-stats [df] = -4.21 [252]).
Conclusion: This study concluded that the pre-lecture activity had successfully provided the students with some prior knowledge of the subject before they attended the lecture sessions. This finding was aligned with cognitive load theory, which describes a reduction in learners' cognitive load when prior knowledge is stimulated.
Revision of Chimarrogale (Lipotyphla: Soricidae) from Vietnam with comments on taxonomy and biogeography of Asiatic water shrews

Abramov AV, Bannikova AA, Lebedev VS, Rozhnov VV

Zootaxa, 2017 Feb 15;4232(2):zootaxa.4232.2.5.
PMID: 28264392 DOI: 10.11646/zootaxa.4232.2.5

We analyzed the complete mitochondrial cytochrome b (cytb) gene and fragments of four nuclear loci: ApoB, RAG2, IRBP1 and BRCA1. These data allowed us to provide new insights into the diversity of the Asiatic water shrews of Indochina. A new, highly divergent genetic lineage of Chimarrogale was found in southern Vietnam, and this lineage included specimens from the provinces of Kon Tum, Dak Lak, and Lam Dong. Such finding represents the newest and southernmost records of Chimarrogale in Indochina. Morphological analysis classified the specimens from southern Vietnam as C. varennei proper, which is restricted to that region, whereas the polymorphic C. himalayica, which contained at least four cytochrome b haplogroups, occurred in central and northern Vietnam and southern China. This distinct C. varennei lineage closely related to the C. platycephalus + C. leander clade suggests the existence of an unknown glacial refuge in Tay Nguyen Plateau, southern Vietnam. Because the Bornean C. phaeura (i) was sister-group of the rest of Chimarrogale sensu lato and (ii) had a high genetic divergence (~15% for cytochrome b) and geographical isolation, we suggest that C. phaeura be placed into a separate genus, Crossogale Thomas, 1921. This genus should also include C. sumatrana (Sumatra) and C. hantu (Peninsular Malaysia). On those grounds, we propose a new classification system for Asiatic water shrews.
Development of an optimization pipeline of asymmetric PCR towards the generation of DNA aptamers: a guide for beginners

Yeoh TS, Anna A, Tang TH, Citartan M

World J Microbiol Biotechnol, 2022 Jan 06;38(2):31.
PMID: 34989899 DOI: 10.1007/s11274-021-03209-w

Asymmetric PCR is one of the most utilized strategies in ssDNA generation towards DNA aptamer generation due to its low cost, robustness and the low amount of starting template. Despite its advantages, careful optimization of the asymmetric PCR is still warranted to optimize the yield of ssDNA. In this present study, we have developed an extensive optimization pipeline that involves the optimization of symmetric PCR initially followed by the optimization of asymmetric PCR. In the asymmetric PCR, optimization of primer amounts/ratios, PCR cycles, annealing temperatures, template concentrations, Mg2+/dNTP concentrations and the amounts of Taq Polymerase was carried out. To further boost the generation of ssDNA, we have also integrated an additional single-stranded DNA generation method, either via lambda exonuclease or biotin-streptavidin-based separation into the optimization pipeline to further improve the yield of ssDNA generation. We have acquired 700 ± 11.3 and 820 ± 19.2 nM for A-PCR-lambda exonuclease and A-PCR-biotin-streptavidin-based separation, respectively. We urge to develop a separate optimization pipeline of asymmetric PCR for each different randomized ssDNA library before embarking on any SELEX studies.
Massive Proteogenomic Reanalysis of Publicly Available Proteomic Datasets of Human Tissues in Search for Protein Recoding via Adenosine-to-Inosine RNA Editing

Levitsky LI, Ivanov MV, Goncharov AO, Kliuchnikova AA, Bubis JA, Lobas AA, et al.

J Proteome Res, 2023 Jun 02;22(6):1695-1711.
PMID: 37158322 DOI: 10.1021/acs.jproteome.2c00740

The proteogenomic search pipeline developed in this work has been applied for reanalysis of 40 publicly available shotgun proteomic datasets from various human tissues comprising more than 8000 individual LC-MS/MS runs, of which 5442 .raw data files were processed in total. This reanalysis was focused on searching for ADAR-mediated RNA editing events, their clustering across samples of different origins, and classification. In total, 33 recoded protein sites were identified in 21 datasets. Of those, 18 sites were detected in at least two datasets, representing the core human protein editome. In agreement with prior artworks, neural and cancer tissues were found to be enriched with recoded proteins. Quantitative analysis indicated that recoding the rate of specific sites did not directly depend on the levels of ADAR enzymes or targeted proteins themselves, rather it was governed by differential and yet undescribed regulation of interaction of enzymes with mRNA. Nine recoding sites conservative between humans and rodents were validated by targeted proteomics using stable isotope standards in the murine brain cortex and cerebellum, and an additional one was validated in human cerebrospinal fluid. In addition to previous data of the same type from cancer proteomes, we provide a comprehensive catalog of recoding events caused by ADAR RNA editing in the human proteome.
Antiviral activity of Embelia ribes Burm. f. against influenza virus in vitro

Hossan MS, Fatima A, Rahmatullah M, Khoo TJ, Nissapatorn V, Galochkina AV, et al.

Arch Virol, 2018 Aug;163(8):2121-2131.
PMID: 29633078 DOI: 10.1007/s00705-018-3842-6

Viral respiratory infections are raising serious concern globally. Asian medicinal plants could be useful in improving the current treatment strategies for influenza. The present study examines the activity of five plants from Bangladesh against influenza virus. MDCK cells infected with influenza virus A/Puerto Rico/8/34 (H1N1) were treated with increasing concentrations of ethyl acetate extracts, and their cytotoxicity (CC50), virus-inhibiting activity (IC50), and selectivity index (SI) were calculated. The ethyl acetate extract of fruits of Embelia ribes Burm. f. (Myrsinaceae) had the highest antiviral activity, with an IC50 of 0.2 µg/mL and a SI of 32. Its major constituent, embelin, was further isolated and tested against the same virus. Embelin demonstrated antiviral activity, with an IC50 of 0.3 µM and an SI of 10. Time-of-addition experiments revealed that embelin was most effective when added at early stages of the viral life cycle (0-1 h postinfection). Embelin was further evaluated against a panel of influenza viruses including influenza A and B viruses that were susceptible or resistant to rimantadine and oseltamivir. Among the viruses tested, avian influenza virus A/mallard/Pennsylvania/10218/84 (H5N2) was the most susceptible to embelin (SI = 31), while A/Aichi/2/68 (H3N2) virus was the most resistant (SI = 5). In silico molecular docking showed that the binding site for embelin is located in the receptor-binding domain of the viral hemagglutinin. The results of this study provide evidence that E. ribes can be used for development of a novel alternative anti-influenza plant-based agent.
Fulltext Depolymerisation of the Klebsiella pneumoniae Capsular Polysaccharide K21 by Klebsiella Phage K5

Lukianova AA, Shneider MM, Evseev PV, Egorov MV, Kasimova AA, Shpirt AM, et al.

Int J Mol Sci, 2023 Dec 09;24(24).
PMID: 38139119 DOI: 10.3390/ijms242417288

Klebsiella pneumoniae is a pathogen associated with various infection types, which often exhibits multiple antibiotic resistance. Phages, or bacterial viruses, have an ability to specifically target and destroy K. pneumoniae, offering a potential means of combatting multidrug-resistant infections. Phage enzymes are another promising therapeutic agent that can break down bacterial capsular polysaccharide, which shields K. pneumoniae from the immune response and external factors. In this study, Klebsiella phage K5 was isolated; this phage is active against Klebsiella pneumoniae with the capsular type K21. It was demonstrated that the phage can effectively lyse the host culture. The adsorption apparatus of the phage has revealed two receptor-binding proteins (RBPs) with predicted polysaccharide depolymerising activity. A recombinant form of both RBPs was obtained and experiments showed that one of them depolymerised the capsular polysaccharide K21. The structure of this polysaccharide and its degradation fragments were analysed. The second receptor-binding protein showed no activity on capsular polysaccharide of any of the 31 capsule types tested, so the substrate for this enzyme remains to be determined in the future. Klebsiella phage K5 may be considered a useful agent against Klebsiella infections.
Comparison of the calcium signaling alterations in GABA-ergic medium spiny neurons produced from iPSCs of different origins

Oshkolova AA, Grekhnev DA, Kruchinina AA, Belikova LD, Volovikov EA, Lebedeva OS, et al.

Biochimie, 2023 Dec 30;222:63-71.
PMID: 38163516 DOI: 10.1016/j.biochi.2023.12.011

Disease models based on induced pluripotent stem cells (iPSCs) are in high demand because of their physiological adequacy and well-reproducibility of the pathological phenotype. Nowadays, the most common approach to generate iPSCs is the reprogramming of somatic cells using vectors based on lentivirus or Sendai virus. We have previously shown impairments of calcium signaling including store-operated calcium entry in Huntington's disease-specific iPSCs-based GABA-ergic medium spiny neurons. However, different approaches for iPSCs generation make it difficult to compare the models since the mechanism of reprogramming may influence the electrophysiological properties of the terminally differentiated neurons. Here, we have studied the features of calcium homeostasis in GABA-ergic medium spiny neurons differentiated from iPSCs obtained from fibroblasts of the same donor using different methods. Our data demonstrated that there were no significant differences neither in calcium influx through the store-operated channels, nor in the levels of proteins activating this type of calcium entry in neurons differentiated from iPSCs generated with lenti- and Sendai viruses-based approaches. We also found no differences in voltage-gated calcium entry for these neurons. Thus, we clearly showed that various methods of cell reprogramming result in similar deregulations in neuronal calcium signaling which substantiates the ability to combine the experimental data on functional studies of ion channels in models based on iPSCs obtained by different methods and expands the prospects for the use of biobanking.
Fulltext Response to dietary supplementation of L-glutamine and L-glutamate in broiler chickens reared at different stocking densities under hot, humid tropical conditions

Shakeri M, Zulkifli I, Soleimani AF, O'Reilly EL, Eckersall PD, Anna AA, et al.

Poult Sci, 2014 Nov;93(11):2700-8.
PMID: 25143595 DOI: 10.3382/ps.2014-03910

A study was conducted to determine whether supplementing AminoGut (a commercial dietary supplement containing a mixture of l-glutamine and l-glutamic acid) to broiler chickens stocked at 2 different densities affected performance, physiological stress responses, foot pad dermatitis incidence, and intestinal morphology and microflora. A randomized design in a factorial arrangement with 4 diets [basal diet, basal diet + 0.5% AminoGut from d 1 to 21, basal diet + 0.5% AminoGut from d 1 to 42, and basal diet + virginiamycin (0.02%) for d 1 to 42] and 2 stocking densities [0.100 m(2)/bird (23 birds/pen; LD) or 0.067 m(2)/bird (35 birds/pen; HD)]. Results showed that villi length and crypt depth were not changed by different dietary treatments. However, birds in the HD group had smaller villi (P = 0.03) compared with those of the LD group. Regardless of diet, HD consistently increased the serum concentrations of ceruloplasmin, α-1 acid glycoprotein, ovotransferin, and corticosterone (P = 0.0007), and elevated heterophil to lymphocyte ratio (0.0005). Neither AminoGut supplementation nor stocking density affected cecal microflora counts. In conclusion, under the conditions of this study, dietary supplementation of AminoGut, irrespective of stocking density, had no beneficial effect on growth performance, intestinal morphology, and physiological adaptive responses of broiler chickens raised under hot and humid tropical conditions. However, AminoGut supplementation from d 1 to 42 was beneficial in reducing mortality rate. Also, the increased serum concentrations of a wide range of acute phase proteins together with elevated corticosterone and heterophil to lymphocyte ratio suggested that high stocking density induced an acute phase response either indirectly as a result of increased incidence of inflammatory diseases such as foot pad dermatitis or possibly as a direct physiological response to the stress of high stocking density.
Aptamers isolated against mosquito-borne pathogens

Navien TN, Yeoh TS, Anna A, Tang TH, Citartan M

World J Microbiol Biotechnol, 2021 Jul 09;37(8):131.
PMID: 34240263 DOI: 10.1007/s11274-021-03097-0

Mosquito-borne diseases are a major threat to public health. The shortcomings of diagnostic tools, especially those that are antibody-based, have been blamed in part for the rising annual morbidity and mortality caused by these diseases. Antibodies harbor a number of disadvantages that can be clearly addressed by aptamers as the more promising molecular recognition elements. Aptamers are defined as single-stranded DNA or RNA oligonucleotides generated by SELEX that exhibit high binding affinity and specificity against a wide variety of target molecules based on their unique structural conformations. A number of aptamers were developed against mosquito-borne pathogens such as Dengue virus, Zika virus, Chikungunya virus, Plasmodium parasite, Francisella tularensis, Japanese encephalitis virus, Venezuelan equine encephalitis virus, Rift Valley fever virus and Yellow fever virus. Intrigued by these achievements, we carry out a comprehensive overview of the aptamers developed against these mosquito-borne infectious agents. Characteristics of the aptamers and their roles in diagnostic, therapeutic as well as other applications are emphasized.
Fulltext The Pathogenesis of the Demyelinating Form of Guillain-Barre Syndrome (GBS): Proteo-peptidomic and Immunological Profiling of Physiological Fluids

Ziganshin RH, Ivanova OM, Lomakin YA, Belogurov AA, Kovalchuk SI, Azarkin IV, et al.

Mol Cell Proteomics, 2016 Jul;15(7):2366-78.
PMID: 27143409 DOI: 10.1074/mcp.M115.056036

Acute inflammatory demyelinating polyneuropathy (AIDP) - the main form of Guillain-Barre syndrome-is a rare and severe disorder of the peripheral nervous system with an unknown etiology. One of the hallmarks of the AIDP pathogenesis is a significantly elevated cerebrospinal fluid (CSF) protein level. In this paper CSF peptidome and proteome in AIDP were analyzed and compared with multiple sclerosis and control patients. A total protein concentration increase was shown to be because of even changes in all proteins rather than some specific response, supporting the hypothesis of protein leakage from blood through the blood-nerve barrier. The elevated CSF protein level in AIDP was complemented by activization of protein degradation and much higher peptidome diversity. Because of the studies of the acute motor axonal form, Guillain-Barre syndrome as a whole is thought to be associated with autoimmune response against neurospecific molecules. Thus, in AIDP, autoantibodies against cell adhesion proteins localized at Ranvier's nodes were suggested as possible targets in AIDP. Indeed, AIDP CSF peptidome analysis revealed cell adhesion proteins degradation, however no reliable dependence on the corresponding autoantibodies levels was found. Proteome analysis revealed overrepresentation of Gene Ontology groups related to responses to bacteria and virus infections, which were earlier suggested as possible AIDP triggers. Immunoglobulin blood serum analysis against most common neuronal viruses did not reveal any specific pathogen; however, AIDP patients were more immunopositive in average and often had polyinfections. Cytokine analysis of both AIDP CSF and blood did not show a systemic adaptive immune response or general inflammation, whereas innate immunity cytokines were up-regulated. To supplement the widely-accepted though still unproven autoimmunity-based AIDP mechanism we propose a hypothesis of the primary peripheral nervous system damaging initiated as an innate immunity-associated local inflammation following neurotropic viruses egress, whereas the autoantibody production might be an optional complementary secondary process.

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