ARID1B, a molecular suppressor of erythropoiesis, is essential for the prevention of Monge’s disease

Azad Priti,Caldwell Andrew B.,Ramachandran Srinivasan,Spann Nathanael J.,Akbari Ali,Villafuerte Francisco C.,Bermudez Daniela,Zhao Helen,Poulsen Orit,Zhou Dan,Bafna Vineet,Subramaniam Shankar,Haddad G 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

At high altitude Andean region, hypoxia-induced excessive erythrocytosis (EE) is the defining feature of Monge’s disease or chronic mountain sickness (CMS). At the same altitude, resides a population that has developed adaptive mechanism(s) to constrain this hypoxic response (non-CMS). In this study, we utilized an in vitro induced pluripotent stem cell model system to study both populations using genomic and molecular approaches. Our whole genome analysis of the two groups identified differential SNPs between the CMS and non-CMS subjects in the ARID1B region. Under hypoxia, the expression levels of ARID1B significantly increased in the non-CMS cells but decreased in the CMS cells. At the molecular level, ARID1B knockdown (KD) in non-CMS cells increased the levels of the transcriptional regulator GATA1 by 3-fold and RBC levels by 100-fold under hypoxia. ARID1B KD in nonCMS cells led to increased proliferation and EPO sensitivity by lowering p53 levels and decreasing apoptosis through GATA1 mediation. Interestingly, under hypoxia ARID1B showed an epigenetic role, altering the chromatin states of erythroid genes. Indeed, combined Real-time PCR and ATAC-Seq results showed that ARID1B modulates the expression of GATA1 and p53 and chromatin accessibility at GATA1/p53 target genes. We conclude that ARID1B is a novel erythroid regulator under hypoxia that controls various aspects of erythropoiesis in high-altitude dwellers.

Development and standardization of a monoclonal antibody-based rapid flow-through immunoassay for the detection of Aphanomyces invadans in the field

B. Adil,K. M. Shankar,B. T. Naveen Kumar,Rajreddy Patil,Abhiman Ballyaya,K. S. Ramesh,Sathish Rama Poojary,Omkar V. Byadgi,Prabhugouda Siriyappagouder 대한수의학회 2013 Journal of Veterinary Science Vol.14 No.4

A monoclonal antibody-based flow-through immunoassay (FTA) was developed using a nitrocellulose membrane placed on the top of adsorbent pads enclosed in a plastic cassette with a test zone at the center. The FTA could be completed within 10 min. Clear purple dots against a white background indicated the presence of Aphanomyces (A.)invadans. The FTA limit of detection was 7 μg/mL for A. invadans compared to 56 μg/mL for the immunodot. FTA and polymerase chain reaction (PCR) could detect A. invadans in fish tissue homogenates at a 10-11 dilution compared to a 10-8 dilution by immunodot. In fish suffering from natural cases of epizootic ulcerative syndrome (EUS)collected from Mangalore, India, FTA and PCR could detect A. invadans in 100% of the samples compared to 89.04%detected by immunodot. FTA reagents were stable and produced expected results for 4 months when stored at 4∼8oC. This rapid test could serve as simple and cost-effective on-site screening tool to detect A. invadans in fish from EUS outbreak areas and in ports during the shipment of live or frozen fish.

Developments in taxol production through endophytic fungal biotechnology: a review

B. Shankar N 경희대학교 융합한의과학연구소 2019 Oriental Pharmacy and Experimental Medicine Vol.19 No.1

Paclitaxel (taxol), a diterpene natural compound was first extracted from the bark of yew trees. However, the method cannot meet its increasing demand on the market due to unprecedented yew cutting, low amounts of taxol production, the laborious and slow process of taxol extraction. Recently, efforts have been made to develop alternative means of taxol production. Microbial fermentation would be a promising method in the production of taxol at industrial scale. Fungal endophytes have the capacity to produce bioactive compounds and can independently synthesize secondary metabolites similar to those made by the host plants. Optimization of the fermentation culture is one of the most important strategies in increasing taxol production by endophytic fungi supplemented with several substances including carbon sources, nitrogen sources, precursors, inducer and the metabolic bypass inhibitors. Improved fermentation techniques and different biotechnological strategies such as gene cloning, gene transformation, mutations are widely being used on endophytic fungi in order to increase the productivity of the taxol. In this review, the different strategies used to produce taxol from endophytic fungal biotechnology have been discussed.

Myositis Ossificans Traumatica Causing Ankylosis of the Elbow

B. Kanthimathi,S. Udhaya Shankar,K. Arun Kumar,V. L. Narayanan 대한정형외과학회 2014 Clinics in Orthopedic Surgery Vol.6 No.4

Myositis ossificans traumatica is an unusual complication following a muscle contusion injury. A significantly large myositic mass causing ankylosis of the elbow is even rarer. We report a 13-year-old boy who presented with a 14-month history of a fixed elbow with no movement and a palpable bony mass in the anterior aspect of the elbow. He had sustained significant trauma to the affected limb 1 month prior to onset of symptoms, which was managed by native massage and bandaging for 4 weeks. The clinicoradiological diagnosis was suggestive of myositis ossificans, and the myositic mass was completely excised. Histopathology revealed lamellar bone. The 2-year follow-up showed full function of the affected limb and no signs of recurrence. We report this case of clinical interest due to the unusually large myositic mass.

Design and Implementation of Comprehensive Converter

Sathyaseelan B.,Vijay Shankar S.,Suresh K.,Saravanan R. 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.6

This novel Comprehensive Converter (CC) proposes multiple power conversion approach for step-up and step-down processes in AC-DC, DC-DC, AC-AC and DC-AC conversions. This versatile converter is designed by using power electronics switches, for AC-DC & AC-AC conversions thyristors are preferred, whereas DC-DC & DC-AC operations require both turn-On and turn-Off control so transistors (IGBT) is the most suitable switch. Conversion in all the stages can be controlled by a digital controller according to the requirement. All four conversions can perform step-up as well as step-down process, so design of inductor and capacitor values are very much important. All four modes of operations 4 thyristor based transistors and two diode based transistors are used to ensure switching operations. Novelty of the research work is conversion of power in all the modes can be bidirectional and also in single stage process, but in the existing systems of power conversions is an unidirectional process. Proposed single stage power conversion has more effi ciency because of low switching losses. This proposed converter was designed by using mathematical analysis, tested at simulation level and verifi ed in the real time experiment

Inverse dynamics of a 3-DOF translational parallel kinematic machine

S. Shankar Ganesh,A. B. Koteswara Rao 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.11

In this paper, kinematics and dynamics modeling of a typical 3-Degree of freedom (DOF) translational Parallel kinematic machine(PKM) is carried out. The kinematic structure of PKM consists of three limbs, connecting the base and the tool platform. Each limb consistsof an arm and a forearm with joints Prismatic-revolute-revolute-revolute (PRRR). The arrangement of joints are in such a way thatthe tool platform will have pure translational motion along the Cartesian axes. Inverse kinematic relations that are necessary to find theslider positions and joint angles for a given position of tool platform are derived. The dynamics model is then derived based on Naturalorhogonal complement (NOC). The inverse dynamics equations presented are used to compute actuator forces. The actuator forces usingNOC are validated with those obtained based on Lagrangian method. The effect of slider, arm, and forearm inertia on the actuator forcesis studied to know whether to neglect the arm and forearm inertias while computing the actuator forces for PKM. Finally, an attempt ismade to find the optimal location of a circular trajectory using Genetic algorithms (GA) with minimization of Grand total actuator force(GTAF) as objective function.

BK polyomavirus infection following COVID-19 infection in renal transplant recipients: a single-center experience

( Hari Shankar Meshram ),( Vivek B. Kute ),( Sanshriti Chauhan ) 대한신장학회 2021 Kidney Research and Clinical Practice Vol.40 No.3

Exergoeconomic Analysis of a Novel Zeotropic Mixture Power System

N. Shankar Ganesh,Uma Maheswari,Tangellapalli Srinivas,B. V. Reddy 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.9 No.1

A parametric investigation of a novel ammonia water mixture power generation system is performed in this study. The overall performance and feasibility of the system of the proposed system are assessed from thermoeconomic, conventional exergy and advanced exergy perspectives. For better heat recovery in the existing medium-temperature heat recovery Kalina system, auxiliary solar heater is considered in the proposed design to improve the overall performance in terms of energy and exergy. The system performance parameters investigated include cycle efficiency, net output, total product cost rate, exergoeconomic factor and total exergy destruction rate. The simulation of the energy and exergy analysis was performed using Python coding. In this respect, the parametric investigation revealed that the cycle efficiency, net output, total product cost rate, exergoeconomic factor and total exergy destruction rate of the system at optimized conditions are 15.5%, 280 kW, 136 $/GJ, 66% and 120 kW, respectively. The irreversibilities of each component and overall system were evaluated and it was found that the turbine accounts for the highest exergy destruction among all components, contributing nearly 13% of the total exergy destruction of the system. Advanced exergy analysis was also performed that involved characterizing the exergy destruction as endogenous, exogenous, avoidable, and unavoidable, leading to specific recommendations for improving the performance of the system. Conventional exergy analysis suggests that the turbine, HE 4 , and separator are the components typically identified for improvement. The advanced exergy analysis in this study, however, indicated that the separator should be the primary focused for performance improvement, followed by the HE 4 and turbine.

Multi-objective optimization of a 3-DOF translational parallel kinematic machine

S. Shankar Ganesh,A. B. Koteswara Rao,Sanjay Darvekar 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.12

In this paper, stiffness modelling and analysis of a typical 3-DOF parallel kinematic machine (PKM) that provides translational motion along X, Y and Z axes is presented. The mechanism consists of three limbs each having an arm and a forearm with prismatic-revoluterevolute- revolute joints (PRRR). The joint arrangement is in such a way that the moving or tool platform maintains same orientation in the entire workspace. Through inverse kinematics, the joint angles for a given position of tool platform necessary for the stiffness modelling and analysis are obtained. The stiffness modelling is based on the compliance matrices of arm and forearm of each limb. Typical non-dimensional performance indices, namely, workspace volume index (WVI), global translational stiffness index (GTSI), and global rotational stiffness index (GRSI), are introduced and used to study the influence of dimensions. Attempts are also made to find the optimal dimensions of the translational PKM using multi-objective optimization based on the genetic algorithms (MOGA) in MATLAB. The methodology presented and the results obtained are useful for predicting the performance capability of the PKM under study.

Design optimization of a 2-DOF parallel kinematic machine based on natural frequency

S. Shankar Ganesh,A. B. Koteswara Rao 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.2

In this paper, kinematics, workspace, and dynamic analysis of a two degree of freedom (2-DOF) translational parallel robot are carried out. The mechanism of the 2-DOF translational parallel robot consists of four links. Links 1 and 2 consist of three revolute joints and link 3 and 4 consist of three revolute joints and one prismatic joint. These four links are attached to the end effector. The inverse kinematics analysis is carried out to find the joint positions for a particular position of the moving platform. Using stiffness and dynamic mass matrices, the natural frequencies of the parallel kinematic machine (PKM) are obtained. Since the first natural frequency is responsible for higher vibrations, the first natural frequency is considered as performance measure of the PKM i.e. global natural frequency index (GNFI). Using GNFI as the objective, the optimal dimensions of the PKM are obtained.