78 results on '"Jaikumar, V."'
Search Results
2. Supramolecular Hydrogel Based Post-Surgical Implant System for Hydrophobic Drug Delivery Against Glioma Recurrence
- Author
-
Wanjale MV, Sunil Jaikumar V, Sivakumar KC, Ann Paul R, James J, and Kumar GSV
- Subjects
glioma ,drug ,delivery ,brain ,tumor ,implant ,surgery ,hydrogel ,Medicine (General) ,R5-920 - Abstract
Mrunal Vitthal Wanjale,1,2 Vishnu Sunil Jaikumar,3 KC Sivakumar,4 Riya Ann Paul,2,5 Jackson James,5 GS Vinod Kumar1 1Nano Drug Delivery Systems (NDDS), Cancer Biology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud P.O, Thiruvananthapuram, Kerala, 695014, India; 2Research Scholar, Department of Biotechnology, Faculty of Applied Sciences & Technology, University of Kerala, Thiruvananthapuram, Kerala, 695581, India; 3Animal Research Facility, Rajiv Gandhi Centre for Biotechnology, Thycaud P.O, Thiruvananthapuram, Kerala, 695014, India; 4Distributed Information Sub-Centre (Bioinformatics Centre), Bio-Innovation Center (BIC), Rajiv Gandhi Centre for Biotechnology, Poojappura, Thiruvananthapuram, Kerala, 695014, India; 5Neuro-Stem Cell Biology Lab, Rajiv Gandhi Centre for Biotechnology, Thycaud P.O, Thiruvananthapuram, Kerala, 695014, IndiaCorrespondence: GS Vinod Kumar, Tel +91 471 2781217, Fax +91 471 2348096, Email gsvinod@rgcb.res.inPurpose: The brain, protected by the cranium externally and the blood–brain barrier (BBB) internally, poses challenges in chemotherapy of aggressive brain tumors. Maximal tumor resection followed by radiation and chemotherapy is the standard treatment protocol; however, a substantial number of patients suffer from recurrence. Systemic circulation of drugs causes myelodysplasia and other side effects. To address these caveats, we report facile synthesis of a polyester-based supramolecular hydrogel as a brain biocompatible implant for in situ delivery of hydrophobic drugs.Methods: Polycaprolactone-diol (PCL) was linked to polyethyleneglycol-diacid (PEG) via an ester bond. In silico modeling indicated micelle-based aggregation of PCL-PEG co-polymer to form a supramolecular hydrogel. Brain biocompatibility was checked in Sprague Dawley rat brain cortex with MRI, motor function test, and histology. Model hydrophobic drugs carmustine and curcumin entrapment propelled glioma cells into apoptosis-based death evaluated by in vitro cytotoxicity assays and Western blot. In vivo post-surgical xenograft glioma model was developed in NOD-SCID mice and evaluated for efficacy to restrict aggressive regrowth of tumors.Results: 20% (w/v) PCL-PEG forms a soft hydrogel that can cover the uneven and large surface area of a tumor resection cavity and maintain brain density. The PCL-PEG hydrogel was biocompatible, and well-tolerated upon implantation in rat brain cortex, for a study period of 12 weeks. We report for the first time the combination of carmustine and curcumin entrapped as model hydrophobic drugs, increasing their bioavailability and yielding synergistic apoptotic effect on glioma cells. Further in vivo study indicated PCL-PEG hydrogel with a dual cargo of carmustine and curcumin restricted aggressive regrowth post-resection significantly compared with control and animals with intravenous drug treatment.Conclusion: PCL-PEG soft gel-based implant is malleable compared with rigid wafers used as implants, thus providing larger surface area contact. This stable, biocompatible, supramolecular gel without external crosslinking can find wide applications by interchanging formulation of various hydrophobic drugs to ensure and increase site-specific delivery, avoiding systemic circulation.Graphical Abstract: Keywords: glioma, drug, delivery, brain, tumor, implant, surgery, hydrogel
- Published
- 2022
3. An Analysis of Future 5G Wireless Sensor Network
- Author
-
Swaminathan, J. N., primary, Alagumeenaakshi, M., additional, Umamaheswari, S., additional, Jaikumar, V., additional, and Kalyan Chakravrthy, N. S., additional
- Published
- 2022
- Full Text
- View/download PDF
4. Thermal design and analysis of 70 K octagonal passive radiant cooler
- Author
-
Subrahmanya, Jaikumar, V, Goutam, Tanneru Sai, and Tijare, D. W.
- Published
- 2021
- Full Text
- View/download PDF
5. A review on three-dimensional eletrochemical systems: analysis of influencing parameters and cleaner approach mechanism for wastewater
- Author
-
GracePavithra, Kirubanandam, Senthil Kumar, P., Jaikumar, V., and SundarRajan, PanneerSelvam
- Published
- 2020
- Full Text
- View/download PDF
6. Microalgae for biofuel production and removal of heavy metals: a review
- Author
-
Pavithra, Kirubanandam Grace, Kumar, P. Senthil, Jaikumar, V., Vardhan, Kilaru Harsha, and SundarRajan, PanneerSelvam
- Published
- 2020
- Full Text
- View/download PDF
7. Crystallization, non-isothermal kinetics and structural analysis of nanocrystalline multiferroic bismuth ferrite (BiFeO3) synthesized by combustion method
- Author
-
Manonmani, M., Jaikumar, V., Gokul Raj, S., and Ramesh Kumar, G.
- Published
- 2019
- Full Text
- View/download PDF
8. A review on cleaner strategies for chromium industrial wastewater: Present research and future perspective
- Author
-
GracePavithra, Kirubanandam, Jaikumar, V., Kumar, P. Senthil, and SundarRajan, PanneerSelvam
- Published
- 2019
- Full Text
- View/download PDF
9. A study of the structural, magnetic, hemocompatibility and electrochemical properties of BiFeO3 (BFO)/CoFe2O4− (CFO) nanocomposite
- Author
-
Manonmani, M., Senthil, V. P., Gajendiran, J., Ramya, J. Ramana, Sivakumar, N., Jaikumar, V., Gokul Raj, S., and Ramesh Kumar, G.
- Published
- 2019
- Full Text
- View/download PDF
10. Prediction and interpretation of adsorption parameters for the sequestration of methylene blue dye from aqueous solution using microwave assisted corncob activated carbon
- Author
-
Tharaneedhar, V., Senthil Kumar, P., Saravanan, A., Ravikumar, C., and Jaikumar, V.
- Published
- 2017
- Full Text
- View/download PDF
11. Design and testing of an ammonia loop heat pipe
- Author
-
Jasvanth, V.S., Adoni, Abhijit A., Jaikumar, V., and Ambirajan, Amrit
- Published
- 2017
- Full Text
- View/download PDF
12. An Experimental Study of Turbocharged Hydrogen Fuelled Internal Combustion Engine
- Author
-
Jilakara, Srinivas, Vaithianathan, Jaikumar V, Natarajan, Saravanan, Ramakrishnan, Venkateswara R, Subash, GP, Abraham, Mathew, Unni, Jayakrishnan Krishnan, and Das, Lalit Mohan
- Published
- 2015
13. Cleaner production on electrochemical removal of sulphonamide from wastewater using three-dimensional electrode system: characterisation and kinetics.
- Author
-
Pavithra, K. Grace, Jaikumar, V., Kumar, P. Senthil, and Sundarrajan, P.
- Subjects
- *
SULFONAMIDES , *GREEN business , *ELECTRIC batteries , *ELECTROCHEMICAL electrodes , *SEWAGE - Abstract
In the examination of increasing interest in emerging pollutants, advanced technologies for emerging pollutants have been focused in the environmental science field. This study focuses on the sulphonamide removal from aqueous phase using designed three-phase three-dimensional electrode reactor. The parameters such as pH, particle electrode concentration, initial concentration of sulphonamide and the applied voltage have been studied using batch experiments. Sulphonamide was removed in 60 min at 12 V, pH 3 and 15 g of particle electrode in an electrochemical cell. From fact-finding, it was concluded that the efficiency of the electrochemical reactor increases with a decrease in pollutant concentration with optimum voltage (12 V). SEM-EDS and FTIR have been used for the characterisation of Sulphuric acid-activated Strychnos potatorum particle electrodes (SASP). The removal of sulphonamide using this reactor followed the pseudo-second-order (R2 > 0.96) and Langmuir–Hinshelwood kinetics (R2 = 0.9504). This newly designed three-dimensional reactor is an effective system for the complete removal of toxic pollutants from wastewater and this can be an alternative to the existing system. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
14. Comparative performance analysis of electrospunTiO 2embedded poly(vinylidene fluoride) nanocomposite membrane for supercapacitors
- Author
-
Arthi, R., primary, Jaikumar, V., additional, and Muralidharan, P., additional
- Published
- 2020
- Full Text
- View/download PDF
15. Development of electrospun PVdF polymer membrane as separator for supercapacitor applications.
- Author
-
Arthi, R., Jaikumar, V., and Muralidharan, P.
- Subjects
- *
POLYMERIC membranes , *POLYVINYLIDENE fluoride , *THERMAL stability , *THERMAL properties , *X-ray diffraction , *SUPERABSORBENT polymers - Abstract
Electrospun Polyvinylidene fluoride (PVdF) membrane is fabricated as a separator for supercapacitor applications. Different weight percentages (5, 10, 15, 20, and 25 wt%) of PVdF were suspended in 50:50 wt% of THF and DMAc solvents, respectively, and electrospinning technique was used to synthesize the polymer separator membranes. The structural morphology was investigated using SEM analysis and thermal stability of the synthesized membranes were determined using TGA and DSC analysis to identify the optimum wt% of PVdF membrane with high porosity, high electrolytic uptake, and lower crystallinity, respectively. It was found that PVdF membrane with 20 wt% exhibited superior properties of lower fiber diameter of about 400 ± 8 nm, high electrolytic uptake of 200 ± 2%, and high porosity of 86.83 ± 2% compared to other synthesized membranes. Further, 20 wt% PVdF membrane was found to be thermally stable up to a temperature of about 450°C. The crystalline nature of the separator membranes were determined using the X-ray diffraction technique. Electrochemical studies (Liner sweep voltammetry) studies revealed that the synthesized PVdF membrane is stable up to 2.5 V. Thus, it was found that PVdF polymer membrane with 20 wt% exhibited superior structural and thermal properties compared to other membranes, making it as a reliable separator membrane for supercapacitors. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
16. Cleaner production on electrochemical removal of sulphonamide from wastewater using three-dimensional electrode system: characterisation and kinetics
- Author
-
Pavithra, K. Grace, primary, Jaikumar, V., additional, Kumar, P. Senthil, additional, and Sundarrajan, P., additional
- Published
- 2020
- Full Text
- View/download PDF
17. Comparative performance analysis of electrospun TiO2 embedded poly(vinylidene fluoride) nanocomposite membrane for supercapacitors.
- Author
-
Arthi, R., Jaikumar, V., and Muralidharan, P.
- Subjects
POLYVINYLIDENE fluoride ,DIFLUOROETHYLENE ,ENERGY storage ,SUPERCAPACITORS ,IONIC conductivity ,NANOCOMPOSITE materials - Abstract
For an efficient energy storage system, effective material is to be used. In the present work, novel poly(vinylidene fluoride)/titanium oxide (PVdF/TiO2) composite membranes were developed using electrospinning technique, as separator for supercapacitors. Different weight percentages of TiO2 nanoparticle (0, 5, 10, 15, and 20 wt%) were mixed with 20 wt% of PVdF in a 50:50 wt% of tetrahydrofuran and dimethylacetamide solvent. Various physical and electrochemical properties including fiber diameter, thermal stability, crystallinity, porosity, and electrolytic uptake were studied to identify the best membrane with optimum TiO2 wt% exhibiting superior characteristics. SEM and TGA studies revealed that the developed PVdF/TiO2 composite membrane with 10 wt% showed improved properties with a lower average diameter of about 66 ± 8 nm, enhanced thermal stability up to 513.15°C and higher porosity of 89%, respectively compared to other membranes. The crystallinity, ionic conductivity, and specific capacitance of the nonwoven separator membranes were determined using X‐ray diffraction technique, electrolytic uptake, and charge–discharge studies, respectively. The present study revealed that the addition of TiO2 nanoparticles improved the physical and thermochemical properties of the separator membrane substantially and PVdF/TiO2 composite membrane with 10 wt% displayed superior performance compared to other membranes. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
18. Development of electrospun PVdF polymer membrane as separator for supercapacitor applications
- Author
-
Arthi, R., primary, Jaikumar, V., additional, and Muralidharan, P., additional
- Published
- 2019
- Full Text
- View/download PDF
19. Influences of nano zero valent ion and Fe2+ supported kaolin nanoparticles for metal ion separation thorough ultrafiltration
- Author
-
Thiyagarajan, K., primary, Arthanareeswaran, G., additional, Kweon, Jihyang, additional, Das, Diganta B., additional, and Jaikumar, V., additional
- Published
- 2019
- Full Text
- View/download PDF
20. An Experimental Study of Turbocharged Hydrogen Fuelled Internal Combustion Engine
- Author
-
Srinivas Jilakara, Jayakrishnan Krishnan Unni, Saravanan Natarajan, Venkateswara R Ramakrishnan, Jaikumar V Vaithianathan, Mathew Abraham, L.M. Das, and GP Subash
- Subjects
Ignition system ,Materials science ,Hydrogen ,chemistry ,Internal combustion engine ,law ,Hydrogen internal combustion engine vehicle ,chemistry.chemical_element ,General Medicine ,Automotive engineering ,Turbocharger ,law.invention - Published
- 2015
21. Crystallization, non-isothermal kinetics and structural analysis of nanocrystalline multiferroic bismuth ferrite (BiFeO3) synthesized by combustion method.
- Author
-
Manonmani, M., Jaikumar, V., Gokul Raj, S., and Ramesh Kumar, G.
- Subjects
- *
DIFFERENTIAL thermal analysis , *COMBUSTION kinetics , *SELF-propagating high-temperature synthesis , *CRYSTALLIZATION , *BISMUTH , *FERRITES , *COMBUSTION - Abstract
The synthesis of bismuth ferrite (BiFeO3) in the nanocrystalline form is described in the present work with the help of self-combustion technique with DL-malic acid as fuel to obtain single-phase BiFeO3 nanopowders. The crystallization behavior for the formation of BiFeO3 was confirmed from the obtained powder diffraction pattern (p-XRD) and thermogravimetric analysis with simultaneous differential thermal analysis. Thermal measurements were carried out in the nitrogen atmosphere to determine the crystallization kinetics through various heating rates from simultaneous thermogravimetric–differential thermal (TG–DTA) analysis curve. The activation energies for the formation of BiFeO3 metal oxides formation were found to be around 124 kJ mol−1 and 113 kJ mol−1 from the phenomenological Johnson–Mehl–Avrami equation or in short JMA. The growth mechanism along three dimensions was observed for all heating rates. The formation of single-phase BFO in nanocrystalline nature was confirmed through microstructural investigations by the use of transmission electron microscopic analysis. The selected area electron diffraction pattern of nanostructure bismuth ferrite for the sample calcinated at 800 °C reveals the diffraction miller indices planes {104} and doublet peaks of {110}, {202} which is in good agreement with that of the present powder XRD pattern. The magnetization for the synthesized samples calcinated indicates that there exists the magnetic order and existence of room-temperature magnetic saturation for the multiferroic BiFeO3. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
22. Influences of nano zero valent ion and Fe2+ supported kaolin nanoparticles for metal ion separation thorough ultrafiltration.
- Author
-
Thiyagarajan, K., Arthanareeswaran, G., Kweon, Jihyang, Das, Diganta B., and Jaikumar, V.
- Subjects
METAL nanoparticles ,METAL ions ,KAOLIN ,ULTRAFILTRATION ,NANOCOMPOSITE materials ,POLYETHERSULFONE ,CELLULOSE acetate - Abstract
In this work, clay based nanocomposite material was synthesized by wet chemical route and nanozero valent ion of kaolin (nZVI:Kaolin) were prepared using sodium borohydride reduction method. The nZVI:Kaolin and Fe:Kaolin nanoparticles were characterized using XRD, FTIR, SEM and antimicrobial activity. The nZVI:Kaolin and Fe:Kaolin were incorporated into polyethersulfone (PES) membranes for metal ion separation through ultrafiltration. The influences of nZVI:Kaolin and Fe supported clay nanoparticles on PES membranes were characterized their modification in functional properties, hydrophilicity and morphological structure. The clean water flux was enhanced to PES membrane by addition of nZVI:Kaolin and Fe:Kaolin nanoparticles. The Cu(II), Ni(II) and Cd(II) metal ions flux was increased for 0.15 wt% of nZVI and Fe:Kaolin nanoparticles in PES which is due to increase in hydrophilicity and change in morphological structure. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
23. Group psycho-education on schizophrenia for caregivers: A pre and post assessment.
- Author
-
Prabhu, N., Jaikumar, V., and Jessy, M. Fatima
- Subjects
- *
MENTAL health services , *SCHIZOPHRENIA , *CAREGIVERS , *SERVICES for caregivers , *FAMILIES , *MENTAL illness - Abstract
Schizophrenia is a serious and long-term mental illness. In the recent decades mental health care system across the world is moving towards community based care and the family caregivers have increased responsibility in managing their ill relatives. Hence caregivers are to be integrated within the mental health treatment plan. Caregivers often face difficulties in fulfilling their roles due to lack of knowledge about illness. This influences the process of caregiving in the form of their expressed emotions which is an important factor during the recovery process of persons with schizophrenia. One of the main contributors to relapse is expressed emotions. Hence, it is inevitable that they need to have knowledge about illness, treatment and available support for effective caring and management. The aim of the study was to assess the effect of psycho-educationon knowledge and expressed emotions of caregivers in the pre and post psycho-educational intervention along with routine out patient treatment. Atotal of 120 caregivers were samples. The study employed a pre and post without control research design where 120 caregivers of persons with Schizophrenia were recruited using purposive sampling technique. They were assessed using Knowledge about Schizophrenia Interview (KASI) and Family Attitude Questionnaire (FAQ) before and after the group intervention which focused on dissemination of information regarding schizophrenia and other psychosocial inputs. The knowledge about diagnosis, symptoms, etiology, medication, course, prognosis and management were found to be improved significantly (t=56.33, p<.000) after psycho-education. The caregivers were found to have a significant decrease in the way they expressed their critical comments, hostility, dissatisfaction and emotional over involvement. They were able to show a higher level of warmth (t-62.96, p<.000) after psychoeducation. Caring for a person with schizophrenia exacts an emotional toll and it might result in a negative emotional atmosphere in the patient's family if they lack knowledge about the illness. This could reduce the caregivers capacity to support their ill relatives. The results prove that a periodic group psycho-education along with routine out patient treatment would be beneficial in providing better care for persons with schizophrenia. [ABSTRACT FROM AUTHOR]
- Published
- 2019
24. A study of the structural, magnetic, hemocompatibility and electrochemical properties of BiFeO3 (BFO)/CoFe2O4− (CFO) nanocomposite.
- Author
-
Manonmani, M., Senthil, V. P., Gajendiran, J., Ramya, J. Ramana, Sivakumar, N., Jaikumar, V., Gokul Raj, S., and Ramesh Kumar, G.
- Subjects
BISMUTH compounds ,X-ray diffraction ,TRANSMISSION electron microscopes ,FERROMAGNETISM ,NANOPARTICLES - Abstract
Pure and (8%, 12% and 16 wt%) Co-doped BiFeO
3 (BFO) samples were synthesized by the gel-combustion method. The obtained samples were subjected to the powder XRD, FE-SEM, EDX, TEM, VSM, and hemocompatibility studies. The structural changes (pure crystalline phase to mixed crystalline phase) were observed in BFO with increased Co concentration in the XRD studies. The FE-SEM and TEM images showed the morphology of the samples, which indicates that spherical/bricks shaped particles were formed. According to the VSM analysis, a change in ferromagnetic behaviour was observed increasing the Co concentration BFO. BFO and doped BFO nanoparticles samples have good biocompatibility has been from the hemocompatibility test analysis. The electrochemical behaviour of BFO and doped BFO was also studied by the cyclic voltammetry (CV) analysis. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
25. Knowledge and expressed emotions of caregivers towards schizophrenia.
- Author
-
Jaikumar, V., Prabhu, N., and Jessy, M. Fatima
- Subjects
- *
SCHIZOPHRENIA , *FAMILIES , *MEDICATION therapy management , *NOSOLOGY , *EMOTIONS , *HOSTILITY - Abstract
Schizophrenia is a severe mental disorder affecting 3-5 / 1000 of the general population at any given time in any society. In India, caregivers in the family play a vital role in providing care by attending to the physical and emotional needs of their ill relatives. It tends to affect young people during their most productive years and, if left untreated, the illness can continue till their end. The management of schizophrenia can be challenging. Hence, it is inevitable that the caregivers need to have knowledge about illness, treatment and available support for effective management. The aim of the study was to examine the level of knowledge about illness and expressed emotions among the caregivers of persons with schizophrenia. The total 120 caregivers who involved in providing care of persons with schizophrenia were samples. The caregivers of persons with schizophrenia diagnosed falling under International Classification of Disease 10 diagnostic criteria were selected using purposive sampling technique. Knowledge about Schizophrenia Interview (KASI) and Family Attitude Questionnaire (FAQ) were used for assessment. The findings revealed that male caregivers have better knowledge in diagnosis (t=2.05*, p<.05) while females have higher knowledge in course and prognosis (t=2.65**, p<.01). They have inadequate knowledge in other dimensions of KASI such as in symptomatology, etiology, medication and management of schizophrenia. They also had higher scores in their expressed emotions like critical comments, hostility, dissatisfaction and emotional over involvement and less score in warmth. The finding suggests need for psycho -educational intervention to enhance knowledge about schizophrenia and to improve positive emotional atmosphere. [ABSTRACT FROM AUTHOR]
- Published
- 2019
26. Influences of nano zero valent ion and Fe2+supported kaolin nanoparticles for metal ion separation thorough ultrafiltration
- Author
-
Thiyagarajan, K., Arthanareeswaran, G., Kweon, Jihyang, Das, Diganta B., and Jaikumar, V.
- Abstract
In this work, clay based nanocomposite material was synthesized by wet chemical route and nanozero valent ion of kaolin (nZVI:Kaolin) were prepared using sodium borohydride reduction method. The nZVI:Kaolin and Fe:Kaolin nanoparticles were characterized using XRD, FTIR, SEM and antimicrobial activity. The nZVI:Kaolin and Fe:Kaolin were incorporated into polyethersulfone (PES) membranes for metal ion separation through ultrafiltration. The influences of nZVI:Kaolin and Fe supported clay nanoparticles on PES membranes were characterized their modification in functional properties, hydrophilicity and morphological structure. The clean water flux was enhanced to PES membrane by addition of nZVI:Kaolin and Fe:Kaolin nanoparticles. The Cu(II), Ni(II) and Cd(II) metal ions flux was increased for 0.15 wt% of nZVI and Fe:Kaolin nanoparticles in PES which is due to increase in hydrophilicity and change in morphological structure.
- Published
- 2019
- Full Text
- View/download PDF
27. New UV-Curable Prepolymer: Synthesis, Characterization, and Kinetics Analysis
- Author
-
Jaikumar, V., primary and Kumar, D., additional
- Published
- 2015
- Full Text
- View/download PDF
28. Synthesis, characterization and kinetic study of photocrosslinkable prepolymer: 2-hydroxy-3-[p-(1-{p-[2-hydroxy-3-(vinylcarbonyloxy)propoxy]phenol}-1-phenylethyl)phenoxy]propyl acrylate
- Author
-
Kumar, D., primary and Jaikumar, V., additional
- Published
- 2015
- Full Text
- View/download PDF
29. Statistical Analysis and Optimization of Acid Dye Biosorption by Brewery Waste Biomass Using Response Surface Methodology
- Author
-
Jaikumar, V., primary and Ramamurthi, V., additional
- Published
- 2009
- Full Text
- View/download PDF
30. Biosorption of Acid Yellow by Spent Brewery Grains in a Batch System: Equilibrium and Kinetic Modelling
- Author
-
Jaikumar, V., primary and Ramamurthi, V., additional
- Published
- 2009
- Full Text
- View/download PDF
31. Effect of Biosorption Parameters Kinetics Isotherm and Thermodynamics for Acid Green Dye Biosorption from Aqueous Solution by Brewery Waste
- Author
-
Jaikumar, V., primary and Ramamurthi, V, additional
- Published
- 2009
- Full Text
- View/download PDF
32. An improved high performance three phase AC-DC boost converter with input power factor correction
- Author
-
Jaikumar, V., primary, Ravi, G., additional, Vijayavelan, V., additional, and Kaliamoorthy, M., additional
- Published
- 2007
- Full Text
- View/download PDF
33. Soft switching commutation circuit for PWM DC-DC converters
- Author
-
VijayaVelan, V., primary, Rami Reddy, B., additional, and Jaikumar, V., additional
- Published
- 2007
- Full Text
- View/download PDF
34. A Retrospective Study of Canine Leptospirosis with Emphasis to Diagnosis and Dark Field Microscopy.
- Author
-
Aipe, A. A., Jaikumar, V. S., Soman, M., and Pillai, U. N.
- Subjects
- *
LEPTOSPIROSIS in animals , *CANIDAE , *RETROSPECTIVE studies , *FIELD ion microscopy , *DIAGNOSTIC examinations , *VACCINE manufacturing , *DISEASES - Abstract
A retrospective study on canine leptospirosis was conducted during February-October' 2013. Three hundred and eighty dogs were screened and blood plasma and urine were subjected to Dark Field Microscopy (DFM). This study showcases the importance of DFM in early diagnosis of leptospirosis and also the need for development of modified vaccine against leptospirosis. [ABSTRACT FROM AUTHOR]
- Published
- 2015
35. Pricing behaviour of the Indian capital market: a comparative analysis in the CAPM, the APT and the macro-economic context
- Author
-
Sood, Anil K., Jaikumar, V., Gupta, G.S., and Sinha, Sidharth
- Subjects
Macroeconomics India ,Price policy India ,Capital market India - Abstract
Research regarding the behaviour of the Indian capital market has been very limited. The risk-return relationship has been studied using only the Capital Asset Pricing Model; and the factor-structure of the return-generating process has not been studied. The present study subjects the CAPM and the APT hypotheses about the risk-return relationship to a series of empirical tests. The factor-structure of the return-generating process is identified using a multi-factor macro-economic model, which draws from the results of the asset pricing research in the West and the macro-econometric studies of the Indian economy. The empirical tests for the two models are based on the standard CAPM and APT methodologies which are modified to suit the Indian conditions. The factor-structure represented by the factor-score series (generated during the factor extraction process of the APT) is identified using a set of eight independent macro-economic variables. The sample returns for this study consist of the weekly returns for 78 securities from the Specified group and 20 securities from the Cash group of the Bombay Stock Exchange for the five year period from 1986 to 1990. The sample period is divided into two overlapping three-year estimation periods (1986-88 and 1987-89) and two non-overlapping one-year test periods (1989 and 1990).Based on the degree of observed normality of the weekly returns, the Specified group sample is divided into two sub-groups. The results suggest that the risk-return relationship in the Indian market is not in accordance with the CAPM hypotheses. The hypothesis of positive relationship between expected returns and the market risk-factor is not supported by the results. However, the prediction about non-pricing of the residual risk-factor is observed to be valid. On the other hand, the hypothesis of joint significance of risk-premia for a set of APT risk-factors is supported during most part of the sample period, especially for the five-factor model. The results suggest that the factor-structure of the return-generating process is characterised by the following systematic risk factors: growth risk with the index of industrial production-electricity as the proxy; interest rate risk with interest rates in the call money and the long-term government securities markets as the proxies; return on alternative assets (gold); inflation risk with Ml as the proxy; external sector performance with exchange rates and imports as the proxies; and investment and credit conditions in the market with M4 as the proxy. Based on these results, it may be concluded that the return-generating process of Indian capital market is characterised by a multi-factor macro-economic model and the risk-return relationship is in accordance with the APT hypothesis.
- Published
- 1995
36. Control systems in non-profit sevice organizations; the case of the state-owned hospital
- Author
-
Ramesh, G., Jaikumar, V., Pandey, I. M., and Giridhar, G.
- Subjects
Non-profit professional service organization ,Management control ,Hospital-administration - Abstract
Complexity of organizations from the point of view of designing control systems, increased as we move from manufacturing to service organizations, and from for-profit to nonprofit organizations. The nonprofit organizations which are also professional organizations would rank as the most complex organizations. Study of literature and cases on nonprofit professional organizations showed that there is need for a critical look at the applicability of the existing framework of management control systems to these organizations. This called for an in-depth study of control systems of such organizations. Public hospitals are excellent example of such organizations. Hospitals are complex organizations, more so if they are state-owned and run on nonprofit lines. Public hospitals in recent times have drawn flak from several quarters for their poor performance. Studies on these hospitals are few and fragmented in nature. There is, therefore, need for an in-depth study of the control system of hospitals from practical side as well. The issues taken up for study in this dissertation are: 1. Identification of the goals of the hospital chosen: and, on the basis of this, identification of the generalized set of goals for hospitals. 2. Manifestation of control system of this hospital, and its congruence with the goals of the hospital. 3. Scope for enhancing the existing framework of control systems for hospitals as representative of professional service organizations. 4. Adaptability of control systems practiced in for profit hospitals for nonprofit hospitals. An exploratory study of this nature would be best served by a comprehensive and indepth study of a public hospital. Three hospitals in Delhi, run by the Central Government, were initially chosen to understand the issues involved in hospital management. After one round of data collection it was decided to concentrate on the All India Institute of Medical Sciences (AIIMS), as it is considered to be premier among the public hospitals. A premier hospital was chosen so that useful inferences can be drawn from it for other hospitals. The goals of the hospital were first identified. They are quality, beach, and resource endowment. Quality can be called the stated goal of AIIMS, and reach the emergent goal. Resource endowment is instrumental to achieving the other goals. Quality and Reach seem to conflict. However, consensus seems to exist among the stakeholders about eh primacy of the goal quality. Later, based on this study a generalized set of goals and their dimensions for hospitals in general has been proposed. The control system, as it operates, is categorized under two processes: ‘Professional control processes and ‘budgetary control system. Professional control is found to be effective in achieving quality but is at dissonance when it comes to achieving reach. The process mechanisms are discussed in terms of goal reiteration, legitimation, selection, and enculturation. At the outset, it seems that outpatient services are maintained to satisfy reach, and the inpatient services for quality. The budgetary control system is found wanting in several respects. The objective of the system seems to be inadequately defined as expenditure control, rather than efficient utilization of resources. The rationale for the system is furnished in terms of the contexts in which the system operates. Considering the peculiarities of the functioning of professional service organizations, which the existing categories of responsibility centre fail to capture, a new concept of Mission Centre has been introduced and its characteristics are outlined. The mission centres are managed by professionals, and they are governed by their values and beliefs, and norms. The values and beliefs are inculcated through the process of enculturation. Norms are derived from professional and organizational considerations. Some propositions have been offered in the light of the discussion on these concepts. In the context of the budgetary control system differences between the ‘DSS Approach’ as prescribed in the literature and perhaps practiced by for- profit organizations and the ‘Vigilance Approach’ as practiced in state-owned nonprofit organizations have been discussed.
- Published
- 1990
37. Performance of new equity share issues: an India experience
- Author
-
Mahendra, Gujarathi, Kuchhal, S.C., Gupta, G.S., and Jaikumar, V.
- Subjects
Capital asset pricing model ,Capital investment ,Investment analysis ,Securities - Abstract
Oversubscription of public issues of new equity shares was a common phenomenon experienced in India during the Seventies. The overwhelming public response to new equity issues, which are normally considered riskier than the existing shares, makes one wonder about their economic justification. This dissertation attempts an enquiry in that direction by examining the performance – measured by risk – during 1970-78. The objectives of the study were: (a) To measure initial performance, that is, performance from the date of closure of subscription list to the date of first quotation. (b) To see if initial performance is significantly different across: (i) different types of new issues, namely initial issues of new companies, further issues of existing non-FERA companies and FERA issues; (ii) different industries; (iii) the issues made at premium and the issues made at par; (iv) different categories of investors as defined by the number of shares applied for. (c) To test empirical validity of some of the popular hypotheses about performance of new issues. (d) To test market efficiency by measuring the after-market performance, that is, performance after the trading has started in the securities. A sample of 98 issues was selected from the newly quoted shares on Bombay Stock Exchange. A modified form of Capital Asset Pricing Model was used to measure the performance. The model accommodates changes in the systematic risk of securities as they get matured. A framework is developed for different methods to compute security return for initial performance. Implications of different financing strategies for new issues are discussed. An approach is given for computation of market return in Indian context. The results show positive initial performance irrespective of the method of computing the security returns. The performance is significantly different across different types of new issues and across different industries. Issues made at premium were not found to be better performers compared to those made at par. Lower categories of investors fetched higher returns compared to higher categories of investors. The results of examination of after-market performance indicate that the new issues continue to yield extra-normal returns up to one month after the trading has started in them. After the first month of trading, however, there are few departures from efficiency. The study has implications for operators in the securities market, corporations making public issues and policy-makers in the field of capital issues.
- Published
- 1981
38. Introducing management control systems for construction projects
- Author
-
Gandhi, S. B., Ganesh, S. R., Jaikumar, V., and Shukla, P. R.
- Subjects
Construction industry management - Abstract
The construction industry plays an important role in the overall economy, social growth and development by its contribution to gross domestic product and employment. It is estimated that during the Sixth plan, the industry might have work potential of about Rs. 47000 crores in major sectors against an outlay of Rs. 82000 crores for the same sectors. The industry employed 11.83 lakhs of people in 1982 and the estimates indicate that above work potential might have generated 14000 million mandays of skilled and semiskilled labour and 6110 million mandays of managerial and technical staff. At the same time there is a growing concern about time and cost overruns on several projects already set up or being set up in India. Construction is one of the major phases of a project. Several reasons for such overruns are attributed to the nature of the construction industry. It is found that this industry is underdeveloped both in terms of trained manpower and essential equipment. Very few construction firms use techniques like networks for planning and delegation of authority at different levels leading to dilution of responsibility. Such dilution ultimately results in delayed during execution of projects. The objectives of the present study, therefore, were the followings: (1) To design a management control system for construction projects on the basis of general framework of control system and techniques of networks. (2) To identify problems of implementing a control system in a large construction firm and suggest solutions to such problems. (3) To test whether or not the organizational change arising due to implementing the new system is helpful to the organization, and (4) To develop measures of effectiveness of the control system. Methodology A large public limited construction firm was selected for the purpose of this study. Date for testing various hypotheses was collected through questionnaires. Pearson’s product moment correlation was used to identify the relationships. Step-regression was used to find out importance of various independent variables in explaining dependent variables. Major Findings (1) The Design and implementation of the management control system on the basis of general framework and techniques of networks were perceived to be leading to improved performance during execution of the project. (2) Implementation of the control system leads to changes in input information available to decision makers, changes in perspectives of decision-makers, and changes in decision process. (3) Perception of pay offs and increased level of communication are more important in affecting decision process. (4) The new system was perceived to be relevant, and people working with it showed higher commitment to and positive attitude towards the system. (5) Relevance of the system is associated with increased with increased level of communication, increased understanding of activities and usefulness of the system. (6) Commitment to the system is associated with felt-need for the system and commitment to the organization. (7) Attitude towards the system is associated with understanding of objectives, purposes and process of the control system. (8) Inspite of diverse requirements of clients and high competition for skilled manpower, R&D activities in construction methods are moderate. (9) The use of mathematical techniques in inventory control and use of computers in the industry are low. (10) Network techniques in planning and control of activities are used moderately.
- Published
- 1985
39. Behavioral perspective of budgeting; an exploratory study set in two fertilizer companies
- Author
-
Premchander, Ganesh, S. R., Jaikumar, V., and Kuchhal, S. C.
- Subjects
Financial planning India ,Budget in business ,Fertiliser industry - Abstract
This study examines budgeting from three different perspectives. 1. Industry practices and the importance of budgeting to organizations. 2. The relationships between the objectives of budgeting (planning evolution, motivation, coordination and education) and certain organizational variables viz. technology, participation, superior, subordinate relationship, need for independence and technical qualification. 3. Interrelationships among, participation, evaluator style, need for independence, performance and technology are studied in the context of budgeting. The fertilizer industry is the setting for the field study. An experiment, in which 71 students of a business school participated, was performed to generate additional data and to validate some of the findings of the field study. Methodology: Questionnaire data was obtained from six companies in the industry and from plant managers of two organizations, senior managers in these two organizations. Senior managers in these two organizations were also interviewed. Company records and publications pertaining to the industry were used to assess the importance of budgeting to organizations and to understand budgeting practices in the industry. The Findings 1. Organizations in the industry use budgets for planning. Budgets are established for all major departments. 2. Performance against the budget is not used for evolution or motivation. 3. The periodicity with which performance is reviewed is low. 4. Operating managers spend little time on the budget activity indicating that it is not viewed as important for day to day operations. 5. Technical education, technology and participation are positively associated with certain dimensions of budgeting viz. planning, coordination and evaluation. 6. Superior subordinate relationship and need for independence are negatively associated with motivation, coordination, evaluation and education. 7. Participation is positively associated with attitude and also with relevance. 8. Need for independence is positively associated with attitude but not participation. 9. Superior-subordinate relationship is positively associated with both attitude and participation. 10. The experimental study does not show an association between participation and performance or between participation and attitude. 11. The evaluator style is not associated with either attitude or performance. 12. Setting budgets does not appear to improve performance. 13. A new look at the impact of participation, budgeting and nature of the task is in order. The study indicates the existence of certain objectives or control. An understanding of the relationship between these objectives and organizational variables aids in the design of control systems and in diagnosing problem areas in the operation of various control systems. The mapping of various interrelationships between dimensions of control on the one hand and organizational variables on the other helps in developing a theory of control systems.
- Published
- 1985
40. Behaviour of stock market prices: information assimilation and market efficiency
- Author
-
Ramachandran, J., Barua, Samir K., Jaikumar, V., and Dixit, Mukund R.
- Subjects
Stock exchange India ,Capital market India - Abstract
The stock market plays an important role in the allocation of capital resources. The market is allocation ally efficient when it maintains equivalent rates of return on comparable investments, for this would channelize funds to those users who utilize them most profitably. The pricing of securities is the principal device by which the market allocates capital. Consequently, the efficiency of the pricing mechanism influences the performance of the stock market, in discharging its role as an allocator of funds. In the past few years, there has been a substantial increase in the activities of the Indian stock markets, particularly with respect to the amount of capital raised. During the period April 1980 to March1982, the amount of funds raised from the stock market was of the order of approximately Rs.950 crores. This is in contrast to the sum of Rs.840 crores (approximately) raised during 19704-9. The Government policy also has favored increased mobilization of resources through the stock market. Given the increased level of activity, it is essential to examine the efficiency of the pricing mechanism of the stock market for the absence of the same would render it a poor allocator of resources. According to the theory of efficient markets, stock markets are efficient when prices fully reflect available information. The theory essentially asserts that ‘by acting on publicly available information it is not possible to improve returns beyond the stock market‘s assessment of what is the fair rate of return. The efficiency of the stock market can be of three kind’s viz., (i) weak form of efficiency (ii) semi-strong form efficiency and (iii) strong-form of efficiency. ' The present study attempts an examination of the weak and the semi- strong forms of efficiency of the pricing mechanism in the Bombay Stock Exchange. Further, the study attempts to estimate the stock market's speed of adjustment to information. The period of study is the six year period-starting from January 1976 and ending with December 1981. Two approaches have been used to investigate into the weak form of market efficiency. The first involves testing for statistical independence of successive price changes. The second approach involves the direct testing of different filter rules to determine whether these rates provide profits greater than a buy and hold strategy. The results of the test of the weak form of efficiency indicate that the historical price» series does not offer exploitable opportunities to the investor. The examination of the semi-strong form of market efficiency was done by analyzing the impact of the announcement of the issue of bonus shares by corporate managements, on the price of equity shares of these companies. Forty bonus issues, declared during the six year period starting January 1976 and ending with December 1981, made up the sample. The Market Model was utilized for isolating the systematic influence on the behavior of security returns. The behavior of the abnormal returns of securities suggests anti- cipation by the market of the declaration of bonus shares. The results indicate that the market tends to corroborate the new information made available with other information at its disposal. The price of the share is determined after taking into account all the available information. The stock market's speed of adjustment to information can be estimated by identify in the beginning and ending times of the adjustment process. Methodology based on the Shewhart control chart theory was employed for ‘Eh s purpose.' The results indicate the existence of two distinct clusters. ..The first cluster includes shares whose adjustment times to new information are short. The second cluster consisted of shares having longer adjustment times. Several implications of the findings of the study have been drawn for the market participants. The limitations of the study and areas of further research have also been indicated.
- Published
- 1985
41. Diffusion-Weighted Imaging Fluid-Attenuated Inversion Recovery Mismatch on Portable, Low-Field Magnetic Resonance Imaging Among Acute Stroke Patients.
- Author
-
Sorby-Adams A, Guo J, de Havenon A, Payabvash S, Sze G, Pinter NK, Jaikumar V, Siddiqui A, Baldassano S, Garcia-Guarniz AL, Zabinska J, Lalwani D, Peasley E, Goldstein JN, Nelson OK, Schaefer PW, Wira CR 3rd, Pitts J, Lee V, Muir KW, Nimjee SM, Kirsch J, Iglesias JE, Rosen MS, Sheth KN, and Kimberly WT
- Subjects
- Humans, Aged, Male, Female, Middle Aged, Aged, 80 and over, Stroke diagnostic imaging, Magnetic Resonance Imaging methods, Diffusion Magnetic Resonance Imaging methods, Ischemic Stroke diagnostic imaging
- Abstract
Objective: For stroke patients with unknown time of onset, mismatch between diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) can guide thrombolytic intervention. However, access to MRI for hyperacute stroke is limited. Here, we sought to evaluate whether a portable, low-field (LF)-MRI scanner can identify DWI-FLAIR mismatch in acute ischemic stroke., Methods: Eligible patients with a diagnosis of acute ischemic stroke underwent LF-MRI acquisition on a 0.064-T scanner within 24 h of last known well. Qualitative and quantitative metrics were evaluated. Two trained assessors determined the visibility of stroke lesions on LF-FLAIR. An image coregistration pipeline was developed, and the LF-FLAIR signal intensity ratio (SIR) was derived., Results: The study included 71 patients aged 71 ± 14 years and a National Institutes of Health Stroke Scale of 6 (interquartile range 3-14). The interobserver agreement for identifying visible FLAIR hyperintensities was high (κ = 0.85, 95% CI 0.70-0.99). Visual DWI-FLAIR mismatch had a 60% sensitivity and 82% specificity for stroke patients <4.5 h, with a negative predictive value of 93%. LF-FLAIR SIR had a mean value of 1.18 ± 0.18 <4.5 h, 1.24 ± 0.39 4.5-6 h, and 1.40 ± 0.23 >6 h of stroke onset. The optimal cut-point for LF-FLAIR SIR was 1.15, with 85% sensitivity and 70% specificity. A cut-point of 6.6 h was established for a FLAIR SIR <1.15, with an 89% sensitivity and 62% specificity., Interpretation: A 0.064-T portable LF-MRI can identify DWI-FLAIR mismatch among patients with acute ischemic stroke. Future research is needed to prospectively validate thresholds and evaluate a role of LF-MRI in guiding thrombolysis among stroke patients with uncertain time of onset. ANN NEUROL 2024;96:321-331., (© 2024 American Neurological Association.)
- Published
- 2024
- Full Text
- View/download PDF
42. Efficacy of intra-arterial carboplatin and bevacizumab in the C6 rat glioma model of glioblastoma multiforme.
- Author
-
Lim J, Santo BA, Baig AA, Ciecierska SK, Donnelly B, Balghonaim S, Levy BR, Jaikumar V, Levy EI, Tutino VM, and Siddiqui AH
- Abstract
Background: Utilizing an endovascular rat glioma model, this study aimed to analyze the efficacy of intra-arterial (IA) carboplatin and bevacizumab delivery with blood-brain barrier breakdown (BBBB) for glioblastoma treatment., Methods: C6-glioma cells were stereotactically injected into the left frontal lobe of Wistar rats. Tumor growth was confirmed on day 8 via MRI. On day 9, a microcatheter was navigated under fluoroscopy from the left femoral artery to the left internal carotid artery. A volume of 2.25 mL of 25% mannitol was administered, followed by either 10 mg/kg of bevacizumab or 2.4 mg/kg of carboplatin. Serial MRI was obtained post-treatment to assess tumor response via analysis of tumor size and radiomics. Histology was analyzed after termination., Results: Control tumor rats and IA mannitol treated tumor rats had fatal tumor growths, with survival until 19.75±2.21 and 36.3±15.1 days, respectively. Carboplatin and bevacizumab treated rats lived >40 days, after which they were euthanized. From serial MRI and histology, IA carboplatin treated rats exhibited tumor regression and resolution by day 35. In IA bevacizumab treated rats, there was tumor regression near the basal ganglia of the brain, closer to the IA chemotherapy injection site, which had reorganized growth patterns. From MRI, 29 unique radiomic features were significantly different between control and treated tumors (notably for total energy and skewness), and treatment responders had a distinct, early manifesting radiomic profile., Conclusion: IA carboplatin and bevacizumab treatment resulted in varying degrees of tumor suppression, validating the first endovascular C6 glioma model as a reliable method to assess new IA therapies., Competing Interests: Competing interests: JL: Research Support: The Society of Vascular and Interventional Neurology Pilot Research Grant, and the Thomas F. Frawley MD Research Fellowship Award. BAS: None. AAB: None. S-SKC: None. BD: None. SB: None. BRL: None. VJ: None. EIL: Board Membership: Stryker, NeXtGen Biologics, MedX Health, Cognition Medical, EndoStream; Consultancy: Claret Medical, GLG Consulting, Guidepoint, Imperative Care, Medtronic, Rebound Therapeutics, StimMed; Employment: University at Buffalo Neurosurgery Inc; Expert Testimony: renders medical/legal opinions as an expert witness; Stock/Stock Options: NeXtGen Biologics, Cognition Medical, Rapid Medical, Claret Medical, Imperative Care, Rebound Therapeutics, StimMed. VMT: Financial Interest/Investor/Stock Options/Ownership: Neurovascular Diagnostics, Inc, QAS.ai, Inc. Grant Support: Brain Aneurysm Foundation, National Science Foundation Award No. 1746694, NIH NINDS award R43 NS115314-0, clinical and translational science institute grant from the national Center for Advancing Translational Sciences of the National Institutes of Health under award number UL1TR001412 to the University at Buffalo. Consultant/Advisory Board: Canon Medical Systems America. AHS: Financial Interest/Investor/Stock Options/Ownership: Adona Medical, Inc, Amnis Therapeutics, Bend IT Technologies, Ltd, BlinkTBI, Inc, Buffalo Technology Partners, Inc, Cardinal Consultants, LLC, Cerebrotech Medical Systems, Inc, Cerevatech Medical, Inc, Cognition Medical, CVAID Ltd, Endostream Medical, Ltd, Imperative Care, Inc, Instylla, Inc, International Medical Distribution Partners, Launch NY, Inc, NeuroRadial Technologies, Inc, Neurotechnology Investors, Neurovascular Diagnostics, Inc, PerFlow Medical, Ltd, Q’Apel Medical, Inc, QAS.ai, Inc, Radical Catheter Technologies, Inc, Rebound Therapeutics Corp (purchased 2019 by Integra Lifesciences, Corp), Rist Neurovascular, Inc (purchased 2020 by Medtronic), Sense Diagnostics, Inc, Serenity Medical, Inc, Silk Road Medical, SongBird Therapy, Spinnaker Medical, Inc, StimMed, LLC, Synchron, Inc, Three Rivers Medical, Inc, Truvic Medical, Inc, Tulavi Therapeutics, Inc, Vastrax, LLC, VICIS, Inc, Viseon, Inc. Consultant/Advisory Board: National Center for Advancing Translational Sciences of the National Institutes of Health under award number UL1TR001412 to the University at Buffalo., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2024
- Full Text
- View/download PDF
43. First Reported Series of Cerebral Angiography Performed at an Outpatient Center: Safety and Satisfaction Results.
- Author
-
Scullen TA, Lian MX, Jaikumar V, Gay JL, Lai PMR, McPheeters MJ, Housley SB, Raygor KP, Bouslama M, Khan HS, Siddiqui AH, Davies JM, Moreland DB, and Levy EI
- Abstract
Background and Objective: Ambulatory surgery centers (ASCs) are increasingly common venues for same-day neurosurgical procedures, allowing for cost-effective, high-quality patient care. We present the first and largest series of patients undergoing diagnostic cerebral angiography at an ASC to demonstrate the effectiveness, safety, and efficiency of outpatient endovascular care., Methods: We retrospectively reviewed data for consecutive patients who underwent diagnostic cerebral angiography at our ASC between January 1, 2024, and May 29, 2024. Data collected included vascular access approach, procedural duration, turnover time, and periprocedural complications. Using a standardized 2-week postprocedural survey, patients were asked to provide comments and rate their subjective satisfaction from a 1 to 5 scale, with "5" being completely satisfied. All cases were performed with a physician team comprising 1 attending neuroendovascular neurosurgery and 1 neuroendovascular fellow present. Fentanyl and midazolam were administered for conscious sedation in all cases., Results: Among the 67 patients included in this series, the mean procedural duration was 29.4 ± 8.6 minutes. The mean turnover time was 13.7 ± 3.6 minutes. Between transradial (46 of 67 [68.7%]) and transfemoral (21 of 67 [31.3%]) access site approaches, there were no statistically significant differences in mean procedural duration (29.4 ± 8.0 vs 29.2 ± 9.9 minutes, respectively; P = .72) or turnover time (14.0 ± 3.9 vs 12.9 ± 2.8 minutes, respectively; P = .4). No complications occurred periprocedurally or within the 2-week follow-up period. A total of 48 (71.6%) of 67 patients responded to the postprocedural survey, all of whom unanimously reported a score of "5.", Conclusion: We found that diagnostic cerebral angiography performed at our ASC was safe and effective for patient care. In addition, all survey respondents (71.6% of those provided the survey) reported highest levels of satisfaction. The integration of neuroendovascular procedures into ASCs potentially offers a cost-effective and highly efficient option in an evolving economic landscape., (Copyright © Congress of Neurological Surgeons 2024. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
44. Decoding Molecular Mechanisms Underlying Outcomes After Ischemic Stroke Thrombectomy by RNA Sequencing of Retrieved Clots.
- Author
-
Santo BA, Poppenberg KE, Ciecierska SS, Lim J, Baig AA, Jaikumar V, Raygor KP, Patel TR, Shah M, Levy EI, Siddiqui AH, and Tutino VM
- Subjects
- Humans, Male, Female, Aged, Middle Aged, Computational Biology methods, Treatment Outcome, Sequence Analysis, RNA, Gene Ontology, Thrombosis genetics, Thrombosis etiology, Gene Regulatory Networks, Thrombectomy, Ischemic Stroke genetics, Ischemic Stroke metabolism, Ischemic Stroke surgery, Transcriptome, Gene Expression Profiling
- Abstract
Background: Transcriptomic profiling has emerged as a powerful tool for exploring the molecular landscape of ischemic stroke clots and providing insights into the pathophysiological mechanisms underlying stroke progression and recovery. In this study, we aimed to investigate the relationship between stroke clot transcriptomes and stroke thrombectomy outcome, as measured by early neurological improvement (ENI) 30 (i.e., a 30% reduction in NIHSS at 24 h post-thrombectomy)., Hypothesis: We hypothesized that there exist distinct clot gene expression patterns between good and poor neurological outcomes., Methods: Transcriptomic analysis of 32 stroke clots retrieved by mechanical thrombectomy was conducted. Transcriptome data of these clots were analyzed to identify differentially expressed genes (DEGs), defined as those with a log(fold-change) ≥ 1.5 and q < 0.05 between samples with good and poor early neurological outcomes. Gene ontology and bioinformatics analyses were performed on genes with p < 0.01 to identify enriched biological processes and Ingenuity Pathway Analysis canonical pathways. Moreover, AUC analysis assessed the predictive power of DEGs for 90-day function outcome (mRS ≤ 2) and cellular composition of clot was predicted using CIBERSORT. We also assessed whether differential enrichment of immune cell types could indicate patient survival., Results: A total of 41 DEGs were identified. Bioinformatics showed that enriched biological processes and pathways emphasized the chronic immune response and matrix metalloproteinase inhibition. Moreover, 25 of the DEGs were found to be significant predictors of 90-day mRS. These genes were indicative of monocytes enrichment and neutrophil depletion in patients with poorer outcomes., Conclusion: Our study revealed a distinct gene expression pattern and dysregulated biological pathways associated with ENI. This expression pattern was also predictive of long-term outcome, suggesting a biological link between those ENIs and 90-day mRS., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)
- Published
- 2024
- Full Text
- View/download PDF
45. Global Disparities in the Presentation and Management of Aneurysmal Subarachnoid Hemorrhage: A Review and Analysis.
- Author
-
Lim J, Aguirre AO, Baig AA, Levy BR, Ladner LR, Crider C, Garay-Morales S, Yu Alfonzo S, Galloza D, Jaikumar V, Monteiro A, Kuo CC, Vakharia K, Lai PMR, Snyder KV, Davies JM, Siddiqui AH, and Levy EI
- Subjects
- Humans, Endovascular Procedures, Intracranial Aneurysm therapy, Intracranial Aneurysm epidemiology, Global Health, Embolization, Therapeutic, Neurosurgical Procedures, Prevalence, Subarachnoid Hemorrhage therapy, Subarachnoid Hemorrhage epidemiology, Healthcare Disparities
- Abstract
Objective: Aneurysmal subarachnoid hemorrhage (aSAH) is associated with high mortality rates. There is a significant gap in the literature describing global disparities in demographics, management, and outcomes among patients with aSAH. We aimed to conduct a systematic review and meta-analysis to assess global disparities in aSAH presentation and management., Methods: PubMed and Embase databases were queried from earliest records to November 2022 for aSAH literature. Presentation, demographics, comorbidities, treatment methods, and outcomes data were collected. Articles that did not report aSAH-specific patient management and outcomes were excluded. Pooled weighted prevalence rates were calculated. Random effects model rates were reported., Results: After screening, 33 articles representing 10,553 patients were included. The prevalence of Fisher grade 3 or 4 aSAH in high- and lower-income countries (HIC and LIC), respectively, was 79.8% (P < 0.01) and 84.1 (P < 0.01). Prevalence of male aSAH patients in HIC and LIC, respectively, was 35.8% (P < 0.01) and 45.0% (P < 0.01). Prevalence of treatment in aSAH patients was 99.5% (P < 0.01) and 99.4% (P = 0.16) in HIC and LIC, respectively. In HIC, 35% (P < 0.01) of aneurysms in aSAH patients were treated with coiling. No LIC reported coiling for aSAH treatment; LIC only reported rates of surgical clipping, with a total prevalence of 92.4% (P < 0.01) versus 65.6% (P < 0.01) in HIC., Conclusion: In this analysis, we found similar rates of high-grade SAH hemorrhages in HIC and LIC but a lack of endovascular coil embolization treatments reported in LIC. Additional research and discussion are needed to identify reasons for treatment disparities and intervenable societal factors to improve aSAH outcomes worldwide., (Copyright © 2024 Elsevier Inc. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
46. Multicenter early United States feasibility study and periprocedural safety of LVIS EVO for the treatment of unruptured intracranial aneurysms.
- Author
-
Kayan Y, Delgado Almandoz JE, Copelan A, Matouk C, Chaudry MI, Altschul D, Essibayi MA, Goren O, Yim B, Tsappidi S, Zhang YJ, Hui FK, Samaniego EA, Gudino A, Siddiqui A, Jaikumar V, Puri AS, Kühn AL, Singh J, Ringer A, Hanel RA, De Toledo OF, Dabus G, Gooch MR, Sizdahkhani S, Field NC, and Paul AR
- Abstract
Background: Stent development has focused recently on low-profile, self-expandable stents compatible with 0.0165 inch microcatheters. The LVIS EVO is the second-generation version of the Low-Profile Visualized Intraluminal Support (LVIS) with improved visibility and resheathability. The LVIS EVO underwent a limited premarket release (PMR) in December 2023. This study aims to report the early safety and feasibility experience with the LVIS EVO stent for the treatment of intracranial aneurysms in the United States (US)., Methods: This was a multicenter, retrospective, observational study evaluating patients who underwent treatment of an intracranial aneurysm with an LVIS EVO stent after the limited PMR. All physicians who had placed an LVIS EVO stent were asked to input their cases after institutional review board approval was obtained. The data were then sent to a single center for analysis. Any patient aged 18 years or older who underwent treatment of an intracranial aneurysm with a LVIS EVO stent in the US was included from the initial PMR in December 2023 until April 2024. Patient age (or ≤90 years old), sex, preoperative modified Rankin Scale (mRS), aneurysm location, aneurysm measurements, and information about preoperative antiplatelet management were all collected. Data on periprocedural complications, 30-day mortality, discharge mRS, and length of stay were also collected., Results: Some 53 patients with 55 aneurysms underwent treatment with the LVIS EVO stent at 15 institutions. All aneurysms were unruptured. The most common location was the anterior communicating artery (35%) followed by the middle cerebral artery bifurcation (31%). All patients were on dual antiplatelet therapy. The average aneurysm size was 5.2 mm with a neck size of 3.7 mm. The smallest distal parent vessel size was 1.2 mm and 36% of stents were deployed in distal parent vessels <2 mm. All (100%) cases had successful deployment and the stent was repositioned in 10% of cases. A single stent was utilized in 91% of cases. Coils were placed in 48 cases (87.2%) and a microcatheter was jailed in 98% of those cases. Immediate Raymond Roy (RR) Class I occlusion was obtained in 33%, Class II in 22%, Class IIIa in 37%, and Class IIIb in 8% of cases. There were no delayed thromboembolic or hemorrhagic complications., Conclusions: The LVIS EVO is a braided, self-expanding, retrievable stent with enhanced visibility and smaller cell size. The drawn filled tube (DFT) technology results in improved visibility of the stent, allowing for more controlled stent positioning and visualization of vessel wall apposition. All cases in our series had complete neck coverage and good wall apposition. There were no thromboembolic or hemorrhagic complications., Competing Interests: Competing interests: BY is a consultant for Imperative Care and Q’Apel Medical, Inc., and has received speaking honoria from Penumbra. EAS is a consultant for MicroVention, Medtronic, Rapid Medical, iSchemaview, and Cerenovus. AS is a consultant/advisory board member for Amnis Therapeutics, Apellis Pharmaceuticals, Inc., Asahi Intecc Co. Ltd., Boston Scientific, Canon Medical Systems USA, Inc., Cardinal Health 200, LLC, Cerebrotech Medical Systems, Inc., CerebrovaKP, Cerenovus, Contego Medical, Cordis, Corindus, Inc., Endostream Medical, Ltd, Hyperfine Operations, Inc., Imperative Care, InspireMD, Ltd., Integra, IRRAS AB, Medtronic, MicroVention, Minnetronix Neuro, Inc., Peijia Medical, Penumbra, Piraeus Medical, Inc., Q’Apel Medical, Inc., Rapid Medical, Serenity Medical, Inc., Shockwave Medical, Inc., Silk Road Medical, StimMed, LLC, Stryker Neurovascular., Synchron Australia Pty Ltd., VasSol, Vesalio, Viz.ai, Inc., WL Gore, and an investor in Adona Medical, Inc., Bend IT Technologies, Ltd., BlinkTBI, Inc., Borvo Medical, Inc., Cerebrotech Medical Systems, Inc., CerebrovaKP, Code Zero Medical, Inc., Cognition Medical, Collavidence, Inc., Contego Medical, CVAID Ltd., E8, Inc., Endostream Medical, Ltd., Galaxy Therapeutics, Inc., Hyperion Surgical, Inc., Imperative Care, Inc., InspireMD, Ltd., Instylla, Inc., Launch NY, Inc., Neurolutions, Inc., NeuroRadial Technologies, Inc. (sold to Medtronic in 2021), Neurovascular Diagnostics, Inc., Peijia Medical, PerFlow Medical, Ltd., Piraeus Medical, Inc., Q’Apel Medical, Inc., QAS.ai, Inc., Radical Catheter Technologies, Inc., Rebound Therapeutics Corp. (purchased 2019 by Integra Lifesciences, Corp.), Rist Neurovascular, Inc. (purchased 2020 by Medtronic), Sense Diagnostics, Inc., Serenity Medical, Inc., Silk Road Medical, Sim & Cure, Spinnaker Medical, Inc., StimMed, LLC, Synchron, Inc., Tulavi Therapeutics, Inc., Vastrax, LLC, Viseon, Inc., Whisper Medical, Inc., Willow Medtech, Inc. OG is a consultant for MicroVention, Stryker, and Route 92. CM is a consultant and proctor for Cerevasc and Silk Road Medical, and a consultant for MicroVention, Medtronic, Stryker, Navigantis, and Hyerbia. MRG is a consultant for Stryker and Rapid Medical. ARP is a consultant for Microvention, IRRAS, Penumbra, and NICO., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2024
- Full Text
- View/download PDF
47. Thrombectomy outcomes for acute ischemic stroke in lower-middle income countries: A systematic review and analysis.
- Author
-
Lim J, Aguirre AO, Rattani A, Baig AA, Monteiro A, Kuo CC, Siddiqi M, Im J, Housley SB, McPheeters MJ, Ciecierska SK, Jaikumar V, Vakharia K, Davies JM, Snyder KV, Levy EI, and Siddiqui AH
- Abstract
Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
- Published
- 2024
- Full Text
- View/download PDF
48. Transvenous embolization of noncavernous dural arteriovenous fistulas (dAVFs): A systematic review and meta-analysis.
- Author
-
Lim J, Donnelly BM, Jaikumar V, Kruk MD, Kuo CC, Monteiro A, Siddiqi M, Baig AA, Patel D, Raygor KP, Snyder KV, Davies JM, Levy EI, and Siddiqui AH
- Abstract
Background: Intracranial dural arteriovenous fistulas (dAVFs) are abnormal connections between arteries and veins within the dura mater. Various treatment modalities, such as surgical ligation, endovascular intervention, and radiosurgery, aim to close the fistulous connection. Although transvenous embolization (TVE) is the preferred method for carotid-cavernous fistulas, its description and outcomes for noncavernous dAVFs vary. This has prompted a systematic review and meta-analysis to comprehensively assess the effectiveness of TVE in treating noncavernous dAVFs, addressing variations in outcomes and techniques., Methods: We searched PubMed and Embase, spanning from the earliest records to December 2022, to identify pertinent English-language articles detailing the utilization of TVE. We focused on specific procedural details, outcomes, and complications in patients older than 18 years. The data collected and analyzed comprised the sample size, number of fistulas, publication specifics, presenting symptoms, fistula grades, and pooled rates of embolizations, outcomes, follow-up information, and complications., Results: From a total of 565 screened articles, 15 retrospective articles encompassing 166 patients spanning across seven countries met the inclusion criteria. Their Newcastle-Ottawa scores ranged from 6 to 8. Intraprocedural complication rate was 10% (95% confidence interval [CI] = 5.9-17.1) and in-hospital postprocedural complication rate was 5.4% (95% CI = 2.8-10.6). Prevalence of in-hospital mortality was 5.5% (95% CI = 2.9-10.6). Complication rate during follow-up was 8.6% (95% CI = 4.7-15.7) with fistula rupture occurring in 5.5% (95% CI = 2.6-11.6) of patients. Complete obliteration rate at final angiographic follow-up was 94.9% (95% CI = 90.3-99.9). Symptoms improved in 95% (95% CI = 89.8-100) of patients at final follow-up., Conclusion: To our knowledge, we present the first meta-analysis assessing obliteration rates, outcomes, and complications of TVE for dAVFs. Our analysis highlights the higher (>90%) complete obliteration rates. Large prospective multicenter studies are needed to better define the utility of TVE for noncavernous dAVFs., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
- Published
- 2024
- Full Text
- View/download PDF
49. Early Termination versus Standard Regimen Duration of Dual Antiplatelet Therapy in Intracranial Aneurysm Patients Treated With Pipeline Embolization Device Flex With Shield Technology: Preliminary Experience of 3 U.S. Centers.
- Author
-
Lim J, Monteiro A, Cortez GM, Benalia VH, Baig AA, Jacoby WT, Donnelly BM, Levy BR, Jaikumar V, Davies JM, Snyder KV, Siddiqui AH, Hanel RA, Levy EI, and Vakharia K
- Subjects
- Humans, Platelet Aggregation Inhibitors therapeutic use, Treatment Outcome, Retrospective Studies, Intracranial Aneurysm diagnostic imaging, Intracranial Aneurysm therapy, Intracranial Aneurysm etiology, Embolization, Therapeutic, Aneurysm, Ruptured diagnostic imaging, Aneurysm, Ruptured therapy, Aneurysm, Ruptured etiology
- Abstract
Background: Pipeline Flex Embolization Device with Shield Technology (PED-Shield) is a third-generation flow diverter with reduced thromboembolic potential. However, safety profile and dual antiplatelet therapy (DAPT) recommendations with PED-Shield is not well -established. We aim to assess the safety and complication profile with early termination of DAPT with use of PED-Shield., Methods: Databases of 3 high-volume cerebrovascular centers were retrospectively reviewed. We identified patients with unruptured and ruptured intracranial aneurysms treated with PED-Shield. Patient demographics, aneurysm characteristics, complications, and angiographic outcomes were extracted. All patients who had early termination of DAPT, defined as <180 days, as well as standard duration were included., Results: A total of 37 patients, totaling 37 aneurysms, had early termination of DAPT and 24 patients with 24 aneurysms received standard duration (>180 days) of DAPT. There was no difference in pre-procedural DAPT regimens between the groups (P = 0.503). Following DAPT termination, o1ne major thromboembolic complication was observed in the early termination group while no major or minor thromboembolic or hemorrhagic complication was noted in the standard duration group. Time of angiographic follow-up was not statistically different (P = 0.063) between the early termination (343 days, interquartile range [IQR] 114-371 days) and the standard duration (175 days, IQR 111-224.5 days) groups. There were no statistically significant differences in complete aneurysm occlusion (P = 0.857), residual neck (P = 0.582), and aneurysm remnant (P = 0.352) rates between the groups on angiography., Conclusions: Early termination of DAPT proves safe after PED-Shield treatment of intracranial aneurysms with comparable complete occlusion rates., (Copyright © 2023 Elsevier Inc. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
50. Mechanical thrombectomy in low Alberta Stroke Program Early Computed Tomographic Score: A systematic review and meta-analysis of randomized controlled trials.
- Author
-
Bouslama M, Baig AA, Raygor KP, Turner RC, Kuo CC, Donnelly BM, Lim J, Monteiro A, Jaikumar V, Lai PMR, Davies JM, Snyder KV, Levy EI, and Siddiqui AH
- Abstract
Background: Due to their poor natural history and lack in level-I evidence, patients with large vessel occlusion and large core infarcts (Alberta Stroke Program Early Computed Tomographic Score <6) have been excluded from receiving mechanical thrombectomy. This systematic review and meta-analysis seeks to summarize current evidence from published randomized controlled trials to compare the safety and efficacy of mechanical thrombectomy with optimal medical therapy in treating stroke patients with large core infarcts., Methods: We searched PubMed and EMBASE for randomized controlled trials investigating the safety and efficacy of mechanical thrombectomy vs optimal medical therapy in patients presenting with large vessel occlusion and large infarcts. Basic demographic and comorbidities were assessed, and clinical outcomes were compared, including modified Rankin scale 0-3, and 0-2 at 3 months, symptomatic intracranial hemorrhage, decompressive hemicortectomy, and 90-day mortality., Results: Three randomized controlled trials totaling 1011 patients (501 and 510 in the medical management and mechanical thrombectomy arm, respectively) were included. Patients undergoing mechanical thrombectomy had significantly higher odds of achieving better functional outcomes at 3 months: Modified Rankin scale 0-2 (OR = 3.05, 95% CI = 2.101-4.4021, p < 0.0001) and modified Rankin scale 0-3 (OR = 2.20, 95% CI = 1.67-2.89, p < 0.0001) as compared to those receiving optimal medical management. There were no differences between groups in 90-day mortality (OR = 0.93, 95% CI = 0.70-1.23, p = 0.60), symptomatic intracranial hemorrhage (OR = 1.89, 95% = CI 0.95-3.77, p = 0.07) or decompressive hemicraniectomy (OR = 1.25, 95% CI = 0.69-2.25, p = 0.46)., Conclusion: Mechanical thrombectomy for patients with large infarcts is associated with improved functional outcomes and a similar safety profile compared to optimal medical management. Ongoing trials will help better refine the target population that benefits the most from treatment.
- Published
- 2023
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.