bluuebunny/crossref_metadata_2025 huggingface dataset:
New method for concentration and quantitation of Mycobacterium leprae
Authors: Sato N , Fieldsteel A H
Published: May 2021

A new method of enumerating Mycobacterium leprae has been developed. Suspensions containing the organisms were filtered through a polycarbonate membrane filter (25-mm diameter, 0.4-micronm pore size, 10-micronm thick; Nucleopore) to concentrate the organisms. The membrane was then mounted on a glass slide and stained with a standard acid-fast stain. Finally, the membrane was treated with a small amount of chloroform to fix it to the slide and make it transparent. This method enabled us to detect M. leprae in quantities as small as 4.98 X 10(2) regardless of the total volume of the original material. Comparison with a standard method for enumerating M. leprae showed that both methods gave similar results when the organisms counted by the standard method were present in sufficient quantity for reproducibility. Because the least number of organisms that can be detected with the standard method is 10(4) ml and because the organisms detected with the new method could be concentrated on the polycarbonate filter from a large amount of infected fluid, a substantial number of suspensions were shown by the new method, but not by the standard method, to contain M. leprae.
New Staphylococcus aureus phage type 94/96(292) associated with a fatal septicemia
Authors: Ward E R , Blouse L E , Davis W R , Weber W R
Published: May 2021

A fulminating septicemia due to Staphylococcus aureus phage type 94/96(292) resulting in the death of a patient with no previous history of illness. This newly characterized strain is identified by an additional typing reaction with experimental phage 292. The prevalence of this strain is discussed.
beta-Glucosidase activity in mycobacteria
Authors: David H L , Jahan M T
Published: May 2021

A procedure to test beta-glucosidase was developed for identification of the mycobacteria. One hundred and thirty-three strains representing 17 species were assayed in a buffered system containing whole cells and the substrate p-nitrophenyl-beta-D-glucoside. Qualitative differences between species indicated that the test was useful in discriminating among the mycobacteria.
Counterimmunoelectrophoresis in the diagnosis of bacterial meningitis
Authors: Colding H , Lind I
Published: May 2021

The aim of the present study was to investigate whether counterimmunoelectrophoresis (CIE) would facilitate the rapid, etiological diagnosis of bacterial meningitis when used in parallel with other routine methods in a medical bacteriological laboratory. Of 3,674 consecutive specimens of cerebrospinal fluid (CSF) received at the Department of Diagnostic Bacteriology, Statens Seruminstitu, 283 specimens (each representing one patient) were selected for examination by CIE on the basis of the following criteria: bacteria or pleocytosis or both by microscopy or positive culture or both. CIE was performed with antisera to Neisseria meningitidis (groups A, B and C), Streptococcus pneumoniae (omni-serum and pools A to 1), and Haemophilus influenzae type b. Antigen was detected in 57% (72/126) of specimens in which cultures revealed these three kinds of microorganisms in CSF and in 12% (17/139) of the culture-negative specimens. CSF specimens from 21 patients with bacterial meningitis caused by other species were all negative in CIE, except four, three of which contained Escherichia coli antigen reacting with antiserum to N. meningitidis group B and one E. coli antigen reacting with antiserum to H. influenzae type b. Specific diagnosis was achieved in 60% (170/283) of the specimens studied and could be extablished within 1 h in 85% (145/170) by the combined results of microscopy and CIE. Ten specimens, nine of which showed a reaction with antiserum to N. meningitidis group A, were positive by CIE only.
Effect of dilution on recovery of bacteria from blood
Authors: Beebe J L , Bourne K A , Ellner P D
Published: May 2021

The multiplication rate of bacteria in undiluted blood containing sodium polyanethol sulfonate was compared with growth rates obtained in dilutions of blood ranging from 1:2 to 1:8. Although all organisms tested grew in the undiluted blood, increased growth rates were seen in the 1:2 dilution. Further dilution resulted in growth rates equivalent to that obtained with the 1:2 dilution. In view of these results, we question the present recommendations that blood be diluted 1:10 or 1:20.
Rapid method for determining nitrate utilization by yeasts
Authors: Hopkins J M , Land G A
Published: May 2021

A test for the nitrate-reductase activity in yeasts has been developed, in which the reaction may be read after only 10 min of incubation. The rapidity of the test is due to the optimization of pH, substrate concentration, and temperature for the reaction.
Comparison of cream of rice agar and horse serum for differentiating germ tubes of Candida albicans from filaments of Candida tropicalis
Authors: Warwood N M , Blazevic D J
Published: May 2021

Simple cream of rice agar was superior to horse serum for the demonstration of germ tubes by Candida albicans and in the differentiation of pseudohyphae of Candida tropicalis from germ tubes at 37 degrees C. Mycelium and chlamydospores were also produced on this medium.
Rapid biochemical tests for characterization of the Mycoplasmatales
Authors: Bradbury J M
Published: May 2021

Methods are described for the rapid detection of beta-D-glucosidase and phosphatase in mycoplasma cultures using fluorogenic 4-methylumbelliferone substrates. These methods were applied to a selection of mycoplasma cultures and were compared with the conventionally used tests for these enzymes. Results were similar by both methods, but the fluorogenic tests could be read after 1 h, whereas the conventional tests took several days.
Variables affecting viral plaque formation in microculture plaque assays using homologous antibody in a liquid overlay
Authors: Randhawa A S , Stanton G J , Green J A , Baron S
Published: May 2021

A liquid antibody microculture plaque assay and the variables that govern its effectiveness are described. The assay is based on the principle that low concentrations of homologous antibody can inhibit secondary plaque formation without inhibiting formation of primary plaques. Thus, clear plaques that followed a linear dose response were produced. The assay was found to be more rapid, less cumbersome, and less expensive than assays using agar overlays and larger tissue culture plates. It was reproducible, quantitative, and had about the same sensitivity as the agar overlay technique in measuring infectious coxsackievirus type B-3. It was more sensitive in assaying adenovirus type 3 and Western equine encephalomyelitis, vesicular stomatitis, Semliki forest, Sendai, Sindbis, and Newcastle disease viruses than were liquid, carboxymethylcellulose, and methylcellulose microculture plaque assays. The variables influencing sensitivity and accuracy, as determined by using coxsackievirus type B-3, were: (i) the inoculum volume of virus; (ii) the incubation period of virus; and (iii) the incubation temperature.
Separation of pathogenic from apathogenic Listeria monocytogenes by three in vitro reactions
Authors: Groves R D , Welshimer H J
Published: May 2021

One-hundred-twelve isolants of Listeria monocytogenes cultured from clinical and nonclinical sources were examined for hemolytic activity by means of the CAMP phenomenon and tested for acidification of xylose and rhamnose. The reactions of the isolants were noted and correlated with the pathogenicity of the organisms. All of the CAMP-negative (nonhemolytic) isolants were apathogenic, and all but one of the CAMP-positive (hemolytic) isolants were pathogenic. All xylose-acidifying isolating isolants were apathogenic, but not all apathogenic isolants were xylose acidifiers. All pathogenic isolants but one were rhamnose acidifiers, but not all rhamnose acidifiers were pathogenic. The pattern of hemolysis, rhamnose acidification, and non-acidification of xylose is associated with pathogenic L. monocytogenes; departure from this pattern is associated with nonpathogenic Listeria, which otherwise share the properties of L. monocytogenes. These in vitro tests should prove useful in screening the apathogenic isolants whose clinical and epidemiological significance should be carefully assessed.
Quantitation of Antibody to Non-Hemagglutinating Viruses by Single Radial Hemolysis: Serological Test for Human Coronaviruses
Authors: Hierholzer John C. , Tannock Gregory A.
Published: May 2021

A single radial hemolysis test was developed for quantitation of specific antibody to non-hemagglutinating viruses. With the human coronaviruses as models, this test utilizes the binding properties of the chromic cation to attach viruses to glutaraldehyde-treated sheep erythrocytes. The most satisfactory system consisted of stabilizing washed sheep erythrocytes with 0.0073% glutaraldehyde for 15 min at 23°C, binding a high concentration of virus to a 25% erythrocyte suspension with 0.0016% chromic chloride for 20 min at 23°C, stopping the reaction with phosphate-saline, and finally mixing the treated, rewashed cells with complement and agarose at 45°C to prepare a slide gel. The gel mix, which was dispensed in plastic plates (23 by 73 mm) in 3-ml volumes, consisted of 1% agarose, 0.1% sodium azide, 5% reconstituted complement, and 0.82% treated cells. Wells 2 mm in diameter were loaded with 5 μl of antiserum, incubated for 18 h at 4°C for diffusion of antiserum and fixation of complement, and then incubated for 8 to 24 h at 37°C for development of hemolysis zones. The diameter of a zone was linearly related to antibody concentration, as determined by conventional serological tests. This single radial hemolysis test was applicable to human and animal coronaviruses and to selected serotypes of the adenovirus, picornavirus, rhabdovirus, and rotavirus groups.
Serological Typing of
Pseudomonas aeruginosa
: Use of Commerical Antisera and Live Antigens
Authors: Brokopp Charles D. , Gomez-Lus Rafael , Farmer J. J.
Published: May 2021

A practical slide agglutination test, with commercial antisera (Difco) and live antigens (antigens of live bacteria) taken directly from 24-h antimicrobial susceptibility plates, has been established for serotyping
Pseudomonas aeruginosa
. Until recently, the lack of both a standard antigenic scheme and a source of commercial antisera has made serological typing of this organism impractical. A simplified procedure with 17 unabsorbed antisera and live antigens prepared from materials readily available in most clinical microbiology laboratories makes epidemiological typing of this organism possible in hospital laboratories. The distribution of each serotype examined in this study was determined by using 425 consecutive patient isolates from six different hospitals. The distribution of O antigen groups (live antigen) was as follows: O1, 11.5%; O2, 1.6%; O3, 3.8%; O4, 7.8%; O5, 4.2% O6, 27.1%; O7,8, 5.9%; O9, 6.8%; O10, 2.4%; O11, 8.2%; O12 through O17, each less than 1%. Ten and six-tenths percent of the above agglutinated in two antisera, 3.3% agglutinated in more than two antisera, and 5.2% did not agglutinate in any antisera. A comparison of live and heated antigens shows that 93.2% were typable with the live antigen, and 94.5% were typable with the heated antigen. When both antigens were used, we typed 96.3% of 725 isolates. The reproductibility and specificity of the serological procedure were examined. We recommend using the live antigen for routine serological typing in clinical microbiology laboratories for “in house” epidemiology and reserving the heated antigen for reference and research typing (and for those few cases where results cannot be obtained using the live antigen). The application of serotyping in the study of outbreaks of
P. aeruginosa
is also presented.
Malar mass due to Actinomyces odontolyticus
Authors: Mitchell P D , Hintz C S , Haselby R C
Published: May 2021

Actinomyces odontolyticus was isolated from a patient with a soft tissue mass in the malar region. The organism was identified on the basis of morphological, cultural, and biochemical characteristics. On histological examination, the tissue mass contained several granulomatous foci with small, basophilic staining areas resembling microscopic sulfur granules. This is believed to be the first reported case of actinomycosis due to A. odontolyticus.
Use of Litmus Milk Agar for Presumptive Identification of Cutaneous Propionibacteria
Authors: Webster Guy F. , McGinley Kenneth J.
Published: May 2021

Presumptive identification of cutaneous propionibacteria can be achieved with litmus milk agar as medium.
Anisotropy of magnetic susceptibility (AMS) of impact melt breccia and target rocks from the Dhala impact structure, India
Authors: Singh* Anuj Kumar , Pati* Jayanta Kumar , Patil Shiva Kumar , Reimold Wolf Uwe , Rao Arun Kumar , Pandey Om Prakash
Published: May 2021

The ~11-km-wide, Paleoproterozoic Dhala impact structure in north-central India comprises voluminous exposures of impact melt breccia. These outcrops are discontinuously spread over a length of ~6 km in a semicircular pattern along the northern, inner limit of the monomict breccia ring around the central elevated area. This study of the magnetic fabrics of impact breccias and target rocks from the Dhala impact structure identified a weak preferred magnetic orientation for pre-impact crystalline target rocks. The pre- and synimpact rocks from Dhala have magnetite and ilmenite as common magnetic phases. The distributions of magnetic vectors are random for most impact melt breccia samples, but some do indicate a preferred orientation. Our anisotropy of magnetic susceptibility (AMS) data demonstrate that the shape of susceptibility ellipsoids for the target rocks varies from prolate to oblate, and most impact melt breccia samples display both shapes, with a slight bias toward the oblate geometry. The average value for the corrected degree of anisotropy of impact melt rock (P′ = 1.009) is lower than that for the target rocks (P′ = 1.091). The present study also shows that both impact melt breccia and target rock samples of the Dhala structure have undergone minor postimpact alteration, and have similar compositions in terms of magnetic phases and high viscosity. Fine-grained iron oxide or hydroxide is the main alteration phase in impact melt rocks. Impact melt rocks gave a narrow range of mean magnetic susceptibility (Km) and P′ values, in contrast to the target rock samples, which gave Km = 0.05–12.9 × 10−3 standard international units (SI) and P′ = 1.036–1.283. This suggests similar viscosity of the source magma, and limited difference in the degrees of recorded deformation. Between Pagra and Maniar villages, the Km value of impact melt breccias gradually decreases in a clockwise direction, with a maximum value observed near Pagra (Km = 1.67 × 10−3 SI). The poor grouping of magnetic fabrics for most impact melt rock samples implies local turbulence in rapidly cooled impact melt at the front of the melt flow immediately after the impact. The mean K1 for most impact melt samples suggests subhorizontal (<5°) flow in various directions. The average value of Km for the target rocks (4.41 × 10−3 SI) is much higher compared to the value for melt breccias (1.09 × 10−3 SI). The results of this study suggest that the melt breccias were likely part of a sheet-like body of sizeable extent. Our magnetic fabric data are also supported by earlier core drilling information from ~70 locations, with coring depths reaching to −500 m. Our extensive field observations combined with available widespread subsurface data imply that the impact melt sheet could have covered as much as 12 km2 in the Dhala structure, with an estimated minimum melt volume of ~2.4 km3.
The first microseconds of a hypervelocity impact
Authors: Gärtner Marie Arnika , Ebert* Matthias , Schimmerohn Martin , Hergarten Stefan , Schäfer Frank , Kenkmann Thomas , Gulde Max
Published: May 2021

The earliest ejection process of impact cratering involves very high pressures and temperatures and causes near-surface material to be ejected faster than the initial impact velocity. On Earth, such material may be found hundreds to even thousands of kilometers away from the source crater as tektites. The mechanism yielding such great distances is not yet fully understood. Hypervelocity impact experiments give insights into this process, particularly as the technology necessary to record such rapid events in high temporal and spatial resolution has recently become available. To analyze the earliest stage of this hypervelocity process, two series of experiments were conducted with a two-stage light-gas gun, one using aluminum and the other using quartzite as target material. The vertical impacts of this study were recorded with a high-speed video camera at a temporal resolution of tens of nanoseconds for the first three microseconds after the projectile’s contact with the target. The images show a self-luminous, ellipsoidal vapor cloud expanding uprange. In order to obtain angle-resolved velocities of the expanding cloud, its entire front and the structure of the cloud were systematically investigated. The ejected material showed higher velocities at high angles to the target surface than at small angles, providing a possible explanation for the immense extent of the strewn fields.
AB0603 THE NEW POSSIBILITIES OF USING CHONDROITIN SULFATE IN PATIENTS WITH KNEE OSTEOARTHRITIS
Authors: Sharapova E. , Kashevarova N. , Taskina E. , Kusevich D. , Alekseeva L. , Lila A.
Published: May 2021

Background:

Administration of Chondroitin Sulfate for treatment of osteoarthritis included treatment types include systemic and parenteral therapies. The benefits of local therapies between difference route is ambivalent.

Objectives:

To evaluate effectiveness and safety of Chondroitin Sulfate (CS) by intramuscular and concomitant (intramuscular and intraarticular) route of administration in patients with knee osteoarthritis (OA).

Methods:

In total 150 patients with knee OA according by ACR criteria and with radiological stages 2 and 3 according to Kellgren-Lawrence were enrolled. Patients were divided by 2 groups: 75 patients (R) received course of 25 intramuscular injection every other day: at the first 3 injection’s in dose 100 mg, and in continue in dose 200 mg, 75 patients in 2nd group (N) received 5 intra-articular injections in target knee in dose 200 mg once per 3 days, in continue 16 intramuscular injections every other day in dose 200 mg. All patients received NSAID - meloxicam in stable dose 15 mg per day. All patients were checked by WOMAC, pain by visual analog scale (VAS), McGiIl Pain Questionnaire (MPQ). At the baseline, standard clinical examination for all patients were blood tests, urine test, coagulation panel and ECG.

Results:

After comparing of two groups by the end of course the intensity of pain by VAS was significantly greater in R group (21,88±13,24 vs 16,81±13,49; р<0,0001). There were no significant differences between groups in improvement of WOMAC, WOMAC subscales and MPQ from baseline. Serious adverse events (AE) were absent. 11 AE’s were detected 3,3% (5/150), but in 100% of cases AE’s were resolved by the end of course.

Conclusion:

CS is effective decreased intensity of pain and stiffness, improved functional ability of joints both intramuscular and concomitant route of administration. However, significantly greater results at pain intensity by VAS shows combination: pain intensity by the end of course was significantly lower in group with concomitant intramuscular and intra-articular injections. Probably, it was associated with faster resolution of synovitis by intraarticular route of administration, that leads to choose this route for patients with comorbidity.

Disclosure of Interests:

None declared.
AB0754 THE INFLUENCE OF PHYSICAL ACTIVITY ON BODY COMPOSITION AND SELF-ESTEEM IN ADULTS WITH JUVENIL IDIOPATHIC ARTHRITIS
Authors: De Oliveira R. , Julio P. , Fernandes P. , Marini R. , Appenzeller S.
Published: May 2021

Background:

With improvement of treatment, long-term factors influencing quality of life have to be addressed in the care of juvenile idiopathic arthritis (JIA) patients.

Objectives:

To compare body composition, level of physical activity and self-esteem of adult patients with JIA with control group (CG).

Methods:

The levels of physical activity were analyzed using the International Physical Activity Questionnaire (IPAQ) short version. The body composition data were collected using the Omrom HBF 514 C vertical electric bioimpedance device. The Rosenberg Self-Esteem Scale was used to assess positive and negative attitude and feelings about themselves, where the lower the score, the higher the individual’s self-esteem. For the statistical analysis of the data, the IBM SPSS software was used with a significance index of p <0.05.

Results:

We included 81 individuals >18 years, 38 with JIA and 43 healthy people. The female sex was the largest participant in this research, being. There was no significant difference regarding sex [female =28 (73.7%) in JIA and 26 (60.5%) in CG] and age of the groups (29.39 ± 7.6 vs. 31.1 ± 3.1, p = 0.18). The CG showed greater height and body weight (163.5 ± 9.8 vs. 169.6 ± 8.0, p<0.001; 63.07 ± 16.65 vs. 69.33 ± 6.88, p = 0.003, respectively), but no difference in Body Mass Index (BMI) was observed (24.32 ± 4.9 vs. 24.12 ± 2.09, p = 0.8). JIA had a higher percentage of total fat mass (31.65 ± 10.20 vs. 28.47 ± 4.9, p = 0.07), while the CG had a higher percentage of total muscle mass (29.7 ± 6.5 vs. 35.86 ± 6.05, p<0.001). The self-esteem of JIA patients was lower than in the CG (21 ± 3.9 vs. 16.26 ± 4.3, p<0.001). In the IPAQ classifications, JIA patients were classified as less physically active than the CG (2.63% vs. 20.93%, p = 0.022), less irregularly active (5.26% vs. 23.25, p = 0.023) and a higher level of sedentary lifestyle (65.78% vs. 25.58%, p<0.001). A higher percentage of muscle mass was associated with greater self-esteem (r=-0.3; p=0.01).

Conclusion:

The low practice of physical activities by patients with JIA seems to directly influence both, their body composition and their self-esteem. These patients should be encouraged to increase physical activity from an early age by a multiprofessional healthcare team to seek improvement their quality of life.

Disclosure of Interests:

None declared
AB0757 ON THE ISSUE OF DIFFERENTIAL DIAGNOSIS OF PANNICULITIS
Authors: Egorova O. , Gorodetskiy V. , Belov B. , Potapova A. , Radenska-Lopovok S. , Probatova N.
Published: May 2021

Background:

Diagnosis of panniculitis (Pn) is associated with significant difficulties due to the variety of etiological factors, which include panniculitis-like T-cell lymphoma (PLTСL) – a rare variant of non-Hodgkin lymphoma.

Objectives:

to study clinical and laboratory features of PLTСL in rheumatology.

Methods:

Over 8 years PLTСL was diagnosed in 10 patients (9 women and 1 man, average age 37.2 ± 7.4) who were referred to V.A. Nasonova Research Institute of Rheumatology with a diagnosis of erythema nodosum or panniculitis. In addition to general clinical study, serum concentrations of α-1 antitrypsin, amylase, lipase, ferritin, creatine phosphokinase, immunological parameters (ANF-Hep2, dsDNA, C3 and C4 complements, CRP, ANCA, Scl-70, antibodies to cardiolipins G and M) were determined, and positron emission tomography combined with computed tomography (PET-CT), histological and immunohistochemical examination (IHC) of the biopsy sample of skin with subcutaneous fat from the affected areas were performed.

Results:

The clinical picture of PLTСL was characterized by generalized red-crimson moderately painful (VAS pain intensity 45mm) subcutaneous nodes on the upper limbs and trunk (100%), face (60%) and lower extremities (75%), without ulceration and oily fluid leakage. A “trembling saucer” symptom was evident in 75% of the observed cases. All patients had febrile fever. No enlargement of the lymph nodes of the liver and spleen was observed. The blood test revealed leukopenia (up to 2.0·x 109 /l) in 50% of cases, an increase in ESR and CRP by three or more times in 100% of cases. The biochemical blood test demonstrated an increase in LDH activity by two or more times in all patients. PET-CT in 100% of cases revealed an intense accumulation of 18F-FDG in the nodes which correlated with a high proliferative activity index. The morphological picture resembled lobular panniculitis without vasculitis. Tumor lymphocytes had an immunophenotype of cytotoxic T-lymphocytes: CD3+, CD8+, granzyme B+. To confirm the tumor nature of the infiltrate the rearrangements of the T-cell receptor genes were studied. Glucocorticoid therapy (23.5±9.6 mg/day) was ineffective which required polychemotherapy in most patients.

Conclusion:

PLTСL presents a complex diagnostic task that requires a multidisciplinary approach to verify the diagnosis and treatment tactics.

Disclosure of Interests:

None declared
Diagnosis and management of a metastatic mixed gestational trophoblastic neoplasia with synchronous primary lung cancer
Authors: Iyengar Varun , Mistry Hetal , Hibbitt Catherine , Shimanovsky Alexei
Published: May 2021

Mixed gestational trophoblastic neoplasias (GTNs) are rare placental tumours that arise from abnormal fertilisation events. To date, only 34 patients with mixed GTNs have been reported in the literature. As such, the management of such cases remains challenging. This report presents a case of a mixed GTN that was further complicated by a synchronous primary lung adenocarcinoma. Our patient was initially treated with hysterectomy, with surveillance labwork showing persistence of her malignancy. She then began combination chemotherapy, at the end of which she appeared to be in remission clinically. Unfortunately, subsequent imaging showed the persistence of pulmonary nodules that were ultimately resected, demonstrating a new primary lung adenocarcinoma. At present, she remains free of both cancers 2 years after her initial diagnosis. The complexity of this case underscores the importance of patient-centred treatment for rare tumours and the role of a multidisciplinary team in the effort to provide holistic care.
Abnormal presentation of haemorrhagic adrenal cyst
Authors: Aboueldahab Kheloud , Yikona Joseph , Hasan Nayeem
Published: May 2021

An 81-year-old patient presented with fever and lethargy for 3 weeks. There were no other signs or symptoms of infection. Detailed history revealed a fall onto his right flank, prior to the start of fever. All microbiological, autoimmune and oncological investigations were negative. CT scan of chest, abdomen and pelvis showed haemorrhage in a previously diagnosed simple adrenal cyst. The cyst was non-functioning. The patient continued to spike fever in the following 4 weeks, otherwise remained stable. The patient was managed conservatively as haemoglobin level was stable. Repeated scan showed signs of improvement. He was discharged after 5 weeks. He remained afebrile and asymptomatic at the planned endocrinology outpatient follow-up after 8 weeks.
Virtual reality in medical students’ education: a scoping review protocol
Authors: Haowen Jiang , Vimalesvaran Sunitha , Myint Kyaw Bhone , Tudor Car Lorainne
Published: May 2021

Background

Virtual reality (VR) is a technology that produces a virtual manifestation of the real world. In recent years, VR has been increasingly used as a tool in medical education. The use of VR in medical education has large potential, as it allows for distance learning and training which may be challenging to deliver in real life. VR encompasses different tools and applications. There is a need to explore how VR has been employed in medical education to date.

Objective

The objective of this scoping review is to conceptualise the VR tools available and the applications of VR in undergraduate medical education as reported in the literature. This scoping review will identify any gaps in this field and provide suggestions for future research.

Methods and analysis

The relevant studies will be examined using the Joanna Briggs Institute methodological framework for scoping studies. A comprehensive search from a total of six electronic databases and grey literature sources will be performed. The reference list of included studies will be screened for additional studies. The screening and data extraction will be done in parallel and independently by two review authors. Any discrepancies will be resolved through consensus or discussion with a third review author. A data extraction form has been developed using key themes from the research questions. The extracted data will be qualitatively analysed and presented in a diagrammatic or tabular form, alongside a narrative summary, in line with Preferred Reporting Items for Systematic Reviews and Meta-Analysis: extension for Scoping Reviews reporting guidelines.

Ethics and dissemination

All data will be collected from published and grey literature. Ethics approval is therefore not a requirement. We will present our findings at relevant conferences and submit them for publications in peer-reviewed journals.
Protocol for a randomised controlled trial for Treatment in Thoracic Aortic Aneurysm: Surgery versus Surveillance (TITAN: SvS)
Authors: Guo Ming Hao , Appoo Jehangir J , Wells George A , Chu Michael , Ouzounian Maral , Fortier Jacqueline , Boodhwani Munir
Published: May 2021

Introduction

Ascending thoracic aortic aneurysm (ATAA) is an asymptomatic condition that can lead to catastrophic events of rupture or dissection. Current guidelines are based on limited retrospective data and recommend surgical intervention for ATAA with a diameter of greater or equal to 5.5 cm. Treatment in Thoracic Aortic Aneurysm: Surgery versus Surveillance is the first prospective, multicentre, randomised controlled trial that compares outcomes of patients undergoing early elective ascending aortic surgery to patients undergoing medical surveillance.

Methods and analysis

Patients between the ages of 18 and 80 with an asymptomatic ATAA between 5.0 cm and 5.4 cm in diameter are eligible for randomisation to early surgery or surveillance. Patients in the surgery group will be followed at 1 month after discharge, then annually for a minimum of 2 years and up to 5 years. Patients in the surveillance group will be followed annually from their index clinic visit for a minimum of 2 years and up to 5 years. The primary outcome is all-cause mortality at follow-up. A sample size of 618 subjects (309 in each group) will achieve an 80% power at a 0.047 significance level.

Ethics and dissemination

This study has received Ottawa Health Science Network Research Ethics Board approval (Protocol 20180007-01H), which was most recently updated on 25 November 2020. The Research Ethics Board have granted approval to the study at 14 participating institutions, including the Ottawa Health Science Network Research Ethics Board. On completion of data analysis, the result of the trial will be presented at national and international conferences, and published in relevant journals, regardless of the finding of the trial.

Trial registration number

NCT03536312.
Synergistic effects of autophagy inhibitors combined with cisplatin against cisplatin-resistant nasopharyngeal cancer cells
Authors: Yin Wei , Xu Jianfeng , Mao Yanjiao
Published: May 2021

This study explored the synergistic effects of autophagy inhibitors combined with cisplatin against cisplatin-resistant nasopharyngeal cancer cells by treating HNE-1 and cisplatin (diamminedichloroplatinum; DDP)-resistant HNE1/DDP nasopharyngeal cancer cell lines with DDP, autophagy inhibitors, or a combination of autophagy inhibitors and DDP. Cell viability was determined via MTT (colorimetric) and colony-forming assays, and the rate of apoptosis was determined using propidium iodide (PI) and annexin V double-staining. The expressions of proteins were determined by Western blotting. For our in-vivo studies, a murine xenograft model was established to evaluate the anti-tumor effects of the combination of autophagy inhibitor and DDP. The results showed that treatment with DDP increased the expressions of ATP-binding cassette sub-family B member 1 (ABCB1), ATP Binding Cassette Subfamily C Member 1 (ABCC1), and P-glycoprotein 1 (P-gp) in the HNE1/DDP cell lines. Treatment with chloroquine decreased the expression levels of ABCB1, ABCC1, and P-gp, and increased the formation of LC3-II and the expression levels of p62 in the HNE1/DDP cells. Additionally, the combination of autophagy inhibitors and DDP produced a synergistic effect on DDP-induced cell death and apoptosis. Furthermore, the combination of the autophagy inhibitor and DDP showed significant anti-tumor effects in the xenograft mouse model. In summary, autophagy inhibitors show synergistic anti-tumor effects with DDP in vitro against DDP-resistant nasopharyngeal cancer cells and in vivo in our xenograft murine model.
Molecular and petrographical evidence for lacustrine environmental and biotic change in the palaeo-Sichuan mega-lake (China) during the Toarcian Oceanic Anoxic Event
Authors: Xu Weimu , Weijers Johan W. H. , Ruhl Micha , Idiz Erdem F. , Jenkyns Hugh C. , Riding James B. , Gorbanenko Olga , Hesselbo Stephen P.
Published: May 2021

The organic-rich upper Lower Jurassic Da'anzhai Member (Ziliujing Formation) of the Sichuan Basin, China is the first stratigraphically well-constrained lacustrine succession associated with the Toarcian Oceanic Anoxic Event (T-OAE;
c.
183 Ma). The expansion of the palaeo-Sichuan mega-lake, probably one of the most extensive freshwater systems to have existed on the planet, is marked by large-scale lacustrine organic productivity and carbon burial during the T-OAE, possibly owing to intensified hydrological cycling and nutrient supply. New molecular biomarker and organic petrographical analyses, combined with bulk organic and inorganic geochemical and palynological data, are presented here, providing insight into aquatic productivity, land-plant biodiversity and terrestrial ecosystem evolution in continental interiors during the T-OAE. We show that lacustrine algal growth during the T-OAE accounted for a significant organic-matter flux to the lakebed in the palaeo-Sichuan mega-lake. Lacustrine water-column stratification during the T-OAE facilitated the formation of dysoxic–anoxic conditions at the lake bottom, favouring organic-matter preservation and carbon sequestration into organic-rich black shales in the Sichuan Basin. We attribute the palaeo-Sichuan mega-lake expansion to enhanced hydrological cycling in a more vigorous monsoonal climate in the hinterland during the T-OAE greenhouse.
A Novel Attack on Monochrome and Greyscale Devanagari CAPTCHAs
Authors: Kumar Mohinder , Jindal Manish Kumar , Kumar Munish
Published: May 2021

The use of computer programs in breaching web site security is common today. CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) and human interaction proofs are the cost-effective solution to these kinds of computer attacks on web sites. These CAPTCHAs are available in many forms, such as those based on text, images and audio. A CAPTCHA must be secure enough that it cannot be broken by a computer program, and it must be usable enough that humans can easily understand it. The most popular is the text-based scheme. Most text-based CAPTCHAs are based on the English language and are not usable by the native people of India. Research has proven that native people are more comfortable with native language–based CAPTCHA. Devanagari-based CAPTCHAs are also available, but the security aspect has not been tested. Unfortunately, English language–based CAPTCHAs are successfully broken. Therefore, it is important to test the security of Devanagari script-based CAPTCHAs. We picked five unique monochrome CAPTCHAs and five unique greyscale CAPTCHAs for testing security. We achieved 88.13% to 97.6% segmentation rates on these schemes and generated six types of features for these segmented characters, such as raw pixels, zoning, projection, Scale-Invariant Feature Transform (SIFT), Speeded-Up Robust Features (SURF) and Oriented Fast and Rotated BRIEF (ORB). For classification, we used three classifiers for comparative analyses. Using k-Nearest Neighbour (k-NN), Support Vector Machine (SVM) and Random Forest, we achieved high recognition on monochrome and greyscale schemes. For monochrome Devanagari CAPTCHAs, the recognition rate of k-NN ranges from 64.78% to 82.39%, SVM ranges from 76.46% to 91.34% and Random Forest ranges from 80.34% to 91.28%. For greyscale Devanagari CAPTCHAs, the recognition rate of k-NN ranges from 67.52% to 85.47%, SVM ranges from 76.9% to 91.71% and Random Forest ranges from 83.07% to 92.13%. We achieved a breaking rate for monochrome schemes of 66% to 85% and for greyscale schemes of 73% to 93%.
Learning Syllables Using Conv-LSTM Model for Swahili Word Representation and Part-of-speech Tagging
Authors: Shivachi Casper Shikali , Mokhosi Refuoe , Shijie Zhou , Qihe Liu
Published: May 2021

The need to capture intra-word information in natural language processing (NLP) tasks has inspired research in learning various word representations at word, character, or morpheme levels, but little attention has been given to syllables from a syllabic alphabet. Motivated by the success of compositional models in morphological languages, we present a Convolutional-long short term memory (Conv-LSTM) model for constructing Swahili word representation vectors from syllables. The unified architecture addresses the word agglutination and polysemous nature of Swahili by extracting high-level syllable features using a convolutional neural network (CNN) and then composes quality word embeddings with a long short term memory (LSTM). The word embeddings are then validated using a syllable-aware language model (
31.267
) and a part-of-speech (POS) tagging task (
98.78
), both yielding very competitive results to the state-of-art models in their respective domains. We further validate the language model using Xhosa and Shona, which are syllabic-based languages. The novelty of the study is in its capability to construct quality word embeddings from syllables using a hybrid model that does not use max-over-pool common in CNN and then the exploitation of these embeddings in POS tagging. Therefore, the study plays a crucial role in the processing of agglutinative and syllabic-based languages by contributing quality word embeddings from syllable embeddings, a robust Conv–LSTM model that learns syllables for not only language modeling and POS tagging, but also for other downstream NLP tasks.
Culturing Human Gut Microbiomes in the Laboratory
Authors: Renwick Simone , Ganobis Caroline M. , Elder Riley A. , Gianetto-Hill Connor , Higgins Gregory , Robinson Avery V. , Vancuren Sarah J. , Wilde Jacob , Allen-Vercoe Emma
Published: May 2021

The human gut microbiota is a complex community of prokaryotic and eukaryotic microbes and viral particles that is increasingly associated with many aspects of host physiology and health. However, the classical microbiology approach of axenic culture cannot provide a complete picture of the complex interactions between microbes and their hosts in vivo. As such, recently there has been much interest in the culture of gut microbial ecosystems in the laboratory as a strategy to better understand their compositions and functions. In this review, we discuss the model platforms and methods available in the contemporary microbiology laboratory to study human gut microbiomes, as well as current knowledge surrounding the isolation of human gut microbes for the potential construction of defined communities for use in model systems.
Recent advances in measuring and understanding the regulation of exercise-mediated protein degradation in skeletal muscle
Authors: Nishimura Yusuke , Musa Ibrahim , Holm Lars , Lai Yu-Chiang
Published: May 2021

Skeletal muscle protein turnover plays a crucial role in controlling muscle mass and protein quality control, including sarcomeric (structural and contractile) proteins. Protein turnover is a dynamic and continual process of protein synthesis and degradation. The ubiquitin proteasome system (UPS) is a key degradative system for protein degradation and protein quality control in skeletal muscle. UPS-mediated protein quality control is known to be impaired in aging and diseases. Exercise is a well-recognized, nonpharmacological approach to promote muscle protein turnover rates. Over the past decades, we have acquired substantial knowledge of molecular mechanisms of muscle protein synthesis after exercise. However, there have been considerable gaps in the mechanisms of how muscle protein degradation is regulated at the molecular level. The main challenge to understand muscle protein degradation is due in part to the lack of solid stable isotope tracer methodology to measure muscle protein degradation rate. Understanding the mechanisms of UPS with the concomitant measurement of protein degradation rate in skeletal muscle will help identify novel therapeutic strategies to ameliorate impaired protein turnover and protein quality control in aging and diseases. Thus, the goal of this present review was to highlight how recent advances in the field may help improve our understanding of exercise-mediated protein degradation. We discuss 1) the emerging roles of protein phosphorylation and ubiquitylation modifications in regulating proteasome-mediated protein degradation after exercise and 2) methodological advances to measure in vivo myofibrillar protein degradation rate using stable isotope tracer methods.
Association of cystic fibrosis transmembrane conductance regulator with epithelial sodium channel subunits carrying Liddle’s syndrome mutations
Authors: Rooj Arun K. , Cormet-Boyaka Estelle , Clark Edlira B. , Qadri Yawar J. , Lee William , Boddu Ravindra , Agarwal Anupam , Tambi Richa , Uddin Mohammed , Parpura Vladimir , Sorscher Eric J. , Fuller Cathy M. , Berdiev Bakhrom K.
Published: May 2021

The association of the cystic fibrosis transmembrane conductance regulator (CFTR) and epithelial sodium channel (ENaC) in the pathophysiology of cystic fibrosis (CF) is controversial. Previously, we demonstrated a close physical association between wild-type (WT) CFTR and WT ENaC. We have also shown that the F508del CFTR fails to associate with ENaC unless the mutant protein is rescued pharmacologically or by low temperature. In this study, we present the evidence for a direct physical association between WT CFTR and ENaC subunits carrying Liddle’s syndrome mutations. We show that all three ENaC subunits bearing Liddle’s syndrome mutations (both point mutations and the complete truncation of the carboxy terminus), could be coimmunoprecipitated with WT CFTR. The biochemical studies were complemented by fluorescence lifetime imaging microscopy (FLIM), a distance-dependent approach that monitors protein-protein interactions between fluorescently labeled molecules. Our measurements revealed significantly increased fluorescence resonance energy transfer between CFTR and all tested ENaC combinations as compared with controls (ECFP and EYFP cotransfected cells). Our findings are consistent with the notion that CFTR and ENaC are within reach of each other even in the setting of Liddle’s syndrome mutations, suggestive of a direct intermolecular interaction between these two proteins.
Electrical match between initial segment and somatodendritic compartment for action potential backpropagation in retinal ganglion cells
Authors: Goethals Sarah , Sierksma Martijn C. , Nicol Xavier , Réaux-Le Goazigo Annabelle , Brette Romain
Published: May 2021

We measured the axial current produced at spike initiation by the axon initial segment of mouse retinal ganglion cells. We found that it is a large current, requiring high sodium channel conductance density, which covaries with cell capacitance so as to ensure a ∼30 mV depolarization. During sustained depolarization the current attenuated, but it broadened to preserve somatic depolarization. Thus, properties of the initial segment are adjusted to ensure backpropagation of the axonal action potential.
The roles of lower- and higher-order surface statistics in tactile texture perception
Authors: Kuroki (黒木 忍) Scinob , Sawayama (澤山 正貴) Masataka , Nishida (西田 眞也) Shin’ya
Published: May 2021

Humans can discriminate subtle spatial patterns differences in the surrounding world through their hands, but the underlying computation remains poorly understood. Here, we 3-D-printed textured surfaces and analyzed the tactile discrimination performance regarding the sensitivity to surface statistics. The results suggest that observers have sensitivity to lower-order statistics whereas not to higher-order statistics. That is, touch differs from vision not only in spatiotemporal resolution but also in (in)sensitivity to high-level surface statistics.
Savings in sensorimotor learning during balance-challenged walking but not reaching
Authors: Bakkum Amanda , Donelan J. Maxwell , Marigold Daniel S.
Published: May 2021

Most everyday tasks challenge our balance. Yet, this aspect of daily motor behavior is often overlooked in adaptation paradigms. Here, we show that challenging balance does not impair sensorimotor adaptation during precision reaching and walking tasks. Furthermore, we show that challenging balance enhances savings of a learned visuomotor mapping during walking. These results provide evidence for the potential performance benefits associated with learning during unconstrained, naturalistic behaviors.
Effects of Seed Priming with Zinc Sulfate on Nutritional Enrichment and Biochemical Fingerprints of Momordica charantia
Authors: Bukhari Shazia Anwer , Farah Nabila , Mahmood Saqib , Altaf Javaria , Mustafa Ghulam
Published: May 2021

Zinc is an essential element for plant growth and development as it plays an important role in various metabolic processes with nutritional enrichment. The treatment with zinc sulfate is also economic. Momordica charantia is an economically important medicinal plant reported for a range of pharmaceutical and pharmacological properties. In this study, nutripriming with zinc sulfate (0.1%, 0.2%, and 0.3% solution) was applied to M. charantia seeds to optimize better dose. Based upon seedling establishment, 0.3% zinc sulfate was selected for final field experiment with randomized complete block design (RCBD) with five replications. Improved germination percentage, vigor, total soluble sugars, chlorophyll-a, chlorophyll-b, total chlorophyll content, and peroxidase activity were observed variably in leaves, fruit, and peel. Other nutritive components showed maintenance in fruits of treated plants indicating that the treatment did not cause any nutritive loss. Antimicrobial activity of leaves (in terms of the minimum inhibitory concentration) against Staphylococcus aureus and Pseudomonas aeruginosa was positively correlated with sinapic acid, vanillic acid, cinnamic acid, syringic acid, chlorogenic acid, benzoic acid, and ferulic acid. It has been concluded from this study that seed priming with zinc sulfate can improve seedling establishment, photosynthetic pigments, and stable nutritive value. Therefore, zinc from zinc sulfate priming has been proved as a beneficial fertilizer for M. charantia plant growth, yield, and nutraceutical potential.