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Search Results: 1 - 10 of 2536 matches for " Chandra Somasundaram "
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Comparing the Surgical Outcomes of Modified Quad and Triangle Tilt Surgeries to other Procedures Performed in Obstetric Brachial Plexus Injury  [PDF]
Rahul K. Nath, Juan-Carlos Pretto, Chandra Somasundaram
Surgical Science (SS) , 2013, DOI: 10.4236/ss.2013.49A003
Abstract:

Purpose: To compare results from our surgical treatment experiences in children with obstetric brachial plexus injuries (OBPI), to those who have had other surgical treatments. Methods: We conducted a retrospective study in our medical records consisting of two groups of OBPI patients. Group 1: 26 OBPI children (16 girls and 10 boys), age range between 2.0 and 12.0 (mean age 6.9), who have undergone surgical treatments at other institutions between 2005 and 2010. Group 2: 45 OBPI children (20 boys and 25 girls), age between 0.7 and 12.9 (mean age 3.7), who have had modified Quad and triangle tilt surgical treatment between 2005 and 2010 at our institution. In both groups Mean modified Mallet scores and radiological scores were measured and compared. All measurements were made at least one year post surgery in both groups. Results: Post-operative mean modified Mallet score was 11.8 ± 2.4 in group 1 patients, whereas post-mean modified Mallet score was 20 ± 2.7 (P < 0.0001) following modified Quad and triangle tilt surgeries in group 2 patients. Further, their radiological scores such as posterior subluxation, and glenoid version were 13.4 ± 21.3 and 30.2 ± 19.1 in group 1, whereas 32.1 ±13.5 (P < 0.0004), and 16.3 ± 11.5 (P < 0.008) in group 2 patients, when compared to normal values of 50, and 0 respectively. Conclusion: Patients who have had mod Quad and triangle tilt for OBPI obtained significantly better functional outcomes in modified total Mallet score as well as in radiological scores, when compared to those OBPI children, who underwent other procedures such as posterior glenohumeral capsulorrhaphy, biceps tendon lengthening, humeral osteotomy, anterior capsule release, nerve transfer/graft, botox and muscle/tendon transfer and release.

Finger movement at birth in brachial plexus birth palsy
Rahul K Nath,Mohamed Benyahia,Chandra Somasundaram
World Journal of Orthopedics , 2013, DOI: 10.5312/wjo.v4.i1.24
Abstract: AIM: To investigate whether the finger movement at birth is a better predictor of the brachial plexus birth injury. METHODS: We conducted a retrospective study reviewing pre-surgical records of 87 patients with residual obstetric brachial plexus palsy in study 1. Posterior subluxation of the humeral head (PHHA), and glenoid retroversion were measured from computed tomography or Magnetic resonance imaging, and correlated with the finger movement at birth. The study 2 consisted of 141 obstetric brachial plexus injury patients, who underwent primary surgeries and/or secondary surgery at the Texas Nerve and Paralysis Institute. Information regarding finger movement was obtained from the patient’s parent or guardian during the initial evaluation. RESULTS: Among 87 patients, 9 (10.3%) patients who lacked finger movement at birth had a PHHA > 40%, and glenoid retroversion < -12°, whereas only 1 patient (1.1%) with finger movement had a PHHA > 40%, and retroversion < -8° in study 1. The improvement in glenohumeral deformity (PHHA, 31.8% ± 14.3%; and glenoid retroversion 22.0° ± 15.0°) was significantly higher in patients, who have not had any primary surgeries and had finger movement at birth (group 1), when compared to those patients, who had primary surgeries (nerve and muscle surgeries), and lacked finger movement at birth (group 2), (PHHA 10.7% ± 15.8%; Version -8.0° ± 8.4°, P = 0.005 and P = 0.030, respectively) in study 2. No finger movement at birth was observed in 55% of the patients in this study group. CONCLUSION: Posterior subluxation and glenoid retroversion measurements indicated significantly severe shoulder deformities in children with finger movement at birth, in comparison with those lacked finger movement. However, the improvement after triangle tilt surgery was higher in patients who had finger movement at birth.
Fall Coloring on Product of Cycles and Powers
Chandra Kumar,T. Nicholas,S. Somasundaram
Journal of Mathematics Research , 2011, DOI: 10.5539/jmr.v3n4p152
Abstract: In this paper, we obtain necessary and sufficient conditions for the existence of fall coloring with fall achromatic number $Delta(G)+1$ in the power of a cycle $C_n^k$ and in the Cartesian product of two cycles.
Virtual screening, identification and experimental testing of novel inhibitors of PBEF1/Visfatin/NMPRTase for glioma therapy
Nagasuma Chandra, Raghu Bhagavat, Eshita Sharma, P Sreekanthreddy, Kumaravel Somasundaram
Journal of Clinical Bioinformatics , 2011, DOI: 10.1186/2043-9113-1-5
Abstract: Virtual screening using docking was used to screen a library of more than 13,000 chemical compounds. A shortlisted set of compounds were tested for their inhibition activity in vitro by an NMPRTase enzyme assay. Further, the ability of the compounds to inhibit glioma cell proliferation was carried out.Virtual screening resulted in short listing of 34 possible ligands, of which six were tested experimentally, using the NMPRTase enzyme inhibition assay and further with the glioma cell viability assays. Of these, two compounds were found to be significantly efficacious in inhibiting the conversion of nicotinamide to NAD+, and out of which, one compound, 3-amino-2-benzyl-7-nitro-4-(2-quinolyl-)-1,2-dihydroisoquinolin-1-one, was found to inhibit the growth of a PBEF1 over expressing glioma derived cell line U87 as well.Thus, a novel inhibitor has been identified through a structure based drug discovery approach and is further supported by experimental evidence.Gliomas are primary malignant tumors, originating in the brain, and account for 80% of adult primary brain tumors. The prognosis for patients with glioblastoma multiforme, a virulent variety of the disease is rather poor, with a median survival of less than one year [1]. Several molecular and biochemical abnormalities such as specific chromosomal aberrations, upregulation of epidermal growth factor receptor (EGFR), loss of phosphate and tensin homology (PTEN), have been clearly associated with gliomas. Some pathways associated with higher grade gliomas are upregulation of PDGFRA (platelet derived growth factor receptor α), CDK4 (cyclin dependent kinase 4) and down-regulation of retinoblastoma (RB1) [1]. NAD+ biosynthesis has been shown to be activated in cancers [2]. NAD+, in addition to its role as a redox cofactor, is also used as a substrate in several biochemical reactions including mono- and poly-ADP ribosylation (ART and PARP catalyzed), protein deacetylation and ADP-ribose cyclization [3]. NMPRTase catalyzes
Identification and Characterization of Novel Perivascular Adventitial Cells in the Whole Mount Mesenteric Branch Artery Using Immunofluorescent Staining and Scanning Confocal Microscopy Imaging
Chandra Somasundaram,Rahul K. Nath,Richard D. Bukoski,Debra I. Diz
International Journal of Cell Biology , 2012, DOI: 10.1155/2012/172746
Abstract: A novel perivascular adventitial cell termed, adventitial neuronal somata (ANNIES) expressing the neural cell adhesion molecule (NCAM) and the vasodilator neuropeptide, calcitonin gene-related peptide (CGRP), exists in the adult rat mesenteric branch artery (MBA) in situ. In addition, we have previously shown that ANNIES coexpress CGRP and NCAM. We now show that ANNIES express the neurite growth marker, growth associated protein-43(Gap-43), palladin, and the calcium sensing receptor (CaSR), that senses changes in extracellular Ca(2+) and participates in vasodilator mechanisms. Thus, a previously characterized vasodilator, calcium sensing autocrine/paracrine system, exists in the perivascular adventitia associated with neural-vascular interface. Images of the whole mount MBA segments were analyzed under scanning confocal microscopy. Confocal analysis showed that the Gap-43, CaSR, and palladin were present in ANNIES about 37 ± 4%, 94 ± 6%, and 80 ± 10% respectively, comparable to CGRP (100%). Immunoblots from MBA confirmed the presence of Gap-43 (48?kD), NCAM (120 and 140?kD), and palladin (90–92 and 140 kD). In summary, CGRP, and NCAM-containing neural cells in the perivascular adventitia also express palladin and CaSR, and coexpress Gap-43 which may participate in response to stress/injury and vasodilator mechanisms as part of a perivascular sensory neural network. 1. Introduction Vascular growth and remodeling occur in association with certain physiological and pathological conditions. In addition, vascular regeneration and repair are essential for the survival of blood vessels. These processes involve numerous cell types. There are still uncharacterized and less characterized cell types in vascular adventitia, which include vascular stem/progenitor cells [1–10] and adventitial neuronal somata (ANNIES) [11]. The vascular adventitia is a complicated tissue [12], which is found to be the most active layer in terms of cell turnover [13]. In addition, within the vascular adventitia resides amyelinated nerves known as “nerva vasorum” [14]. Using fluorescence confocal microscopy (FCM) to visualize vascular wall 3D organization of different cellular and extracellular elements of the intact artery with minimal 3D distortion [11, 13], we recently demonstrated ANNIES coexpressing neural cell adhesion molecule (NCAM) and calcitonin gene-related peptide (CGRP) in the adult rat mesenteric branch artery (MBA). These cells can be enzymatically dispersed and maintained in culture [11]. The present study was designed to further characterize ANNIES in adult rat MBA as
Arm rotated medially with supination – the ARMS variant: description of its surgical correction
Rahul K Nath, Chandra Somasundaram, Sonya E Melcher, Meera Bala, Melissa J Wentz
BMC Musculoskeletal Disorders , 2009, DOI: 10.1186/1471-2474-10-32
Abstract: Fourteen OBPI patients were diagnosed with MRC of the shoulder and SD of the forearm along with SHEAR deformity during a 16 month study period, with eight patients available to long-term follow-up (age range 2.2 – 18 years). Surgical correction of the MRC was performed as a triangle tilt or humeral osteotomy depending on the age of the child, after which, the patients were treated with a radial osteotomy to correct the fixed supination deformity. Function was assessed using the modified Mallet scale, examination of apparent supination and appearance of the extremity at rest.Significant functional improvements were observed in patients with surgical reconstruction. Mallet score increased by an average of 5.2 (p < 0.05). Overall forearm position was not significantly changed from an average of 5° to an average of 34° maximum apparent supination after both shoulder rotation and forearm rotation corrective surgeries.The simultaneous presence of two opposing deformities in the same limb will visually offset each other at the level of the wrist and hand, giving the false impression of neutral positioning of the limb. In reality, the neutral-appearing position of the hand indicates a fixed supination posture of the forearm in the face of a medial rotation contracture of the shoulder. Both of these deformities require surgical attention, and the presence of concurrent MRC and SD should be monitored for in OBPI patients.Secondary deformities are common following obstetric brachial plexus injury (OBPI). Two well-described secondary deformities are the medial rotation contracture (MRC) of the arm and the fixed supination deformity (SD) of the forearm. Each has been described individually, but the simultaneous presence of both in the same patient, which we term Arm Rotated Medially with Supination, or the ARMS variant of MRC, has not previously been emphasized.The MRC is a major cause of shoulder deformity in children with OBPI, requiring surgery in more than one third of patie
QoS Aware Power and Hop Count Constraints Routing Protocol with Mobility Prediction for MANET Using SHORT  [PDF]
Senthilkumar Maruthamuthu, Somasundaram Sankaralingam
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2011, DOI: 10.4236/ijcns.2011.43023
Abstract: A mobile ad hoc network (MANET) is composed of mobile nodes, which do not have any fixed wired communication infrastructure. This paper proposes a protocol called “Delay, Jitter, Bandwidth, Cost, Power and Hop count Constraints Routing Protocol with Mobility Prediction for Mobile Ad hoc Network using Self Healing and Optimizing Routing Technique (QPHMP-SHORT)”. It is a multiple constraints routing protocol with self healing technique for route discovery to select a best routing path among multiple paths between a source and a destination as to increase packet delivery ratio, reliability and efficiency of mobile communication. QPHMP-SHORT considers the cost incurred in channel acquisition and the incremental cost proportional to the size of the packet. It collects the residual battery power of each node for each path; selects multiple paths, which have nodes with good battery power for transmission to satisfy the power constraint. QPHMP-SHORT uses Self-Healing and Optimizing Routing Technique (SHORT) to select a shortest best path among multiple selected paths by applying hops count constraint. It also uses the mobility prediction formula to find the stability of a link between two nodes.
Wireless Sensor Network Lifetime Enhancement Using Modified Clustering and Scheduling Algorithm  [PDF]
K. Ramesh, K. Somasundaram
Circuits and Systems (CS) , 2016, DOI: 10.4236/cs.2016.78154
Abstract: Random distribution of sensor nodes in large scale network leads redundant nodes in the application field. Sensor nodes are with irreplaceable battery in nature, which drains the energy due to?repeated collection of data and decreases network lifetime. Scheduling algorithms are the one way?of addressing this issue. In proposed method, an optimized sleep scheduling used to enhance the?network lifetime. While using the scheduling algorithm, the target coverage and data collection?must be maintained throughout the network. In-network, aggregation method also used to remove the unwanted information in the collected data in level. Modified clustering algorithm?highlights three cluster heads in each cluster which are separated by minimum distance between them.?The simulation results show the 20% improvement in network lifetime, 25% improvement in?throughput and 30% improvement in end to end delay.
Protective Effect of Type I Collagen Antisense Oligonucleotides on Bleomycin Induced Pulmonary Fibrosis
Rahul K. Nath, Chandra Somasundaram, Weijun Xiong, Jessica Li, Ka BianFerid MuradBackgroundMethodsCOL1A1ResultsConclusion
The Open Conference Proceedings Journal , 2010, DOI: 10.2174/2210289201001010141]
Abstract: Background: Pulmonary fibrosis is a chronic and usually untreatable fatal lung disease. It can result from many endogenous or exogenous causes, such as infection, chronic inflammatory diseases, environmental toxins, chemical poisoning, radiation and chemotherapy. The accumulation of collagen, largely type I collagen rich extracellular matrix (ECM) is the hallmark of lung fibrosis. Current therapies for pulmonary fibrosis utilizing corticosteroids and immunosupressants have demonstrated only marginal effectiveness. Methods: In the present study, we tested the efficacy of the mouse type 1 collagen antisense oligodeoxynucleotides (AS61-ODN, a 20 mer) in bleomycin induced pulmonary fibrosis in mice. Bleomycin was instilled transtracheally by direct tracheal cut down in mice, and oligonucleotides (ODN) were injected through the tail vein. Hematoxylin and eosin (H & E) and Masson’s trichrome staining were done to determine the cellular architecture of the lungs after bleomycin and oligonucleotide treatment. Type I procollagen gene COL1A1 expression was determined by Northern blot analysis. Type I collagen protein expression was determined by Western blot analysis and immunofluorescence. Results: There was much less disruption of the lung architecture as indicated by significant decrease in the Ashcroft score, when mice were injected with AS61-ODN following bleomycin instillation. AS61-ODN significantly reduced the mRNA and protein expression of type 1 collagen by 45.2 % (p < 0.015) and 35.0 % (p < 0.004) respectively 21 days after treatment in bleomycin induced fibrotic lung tissue. Immunofluorescence of bleomycin induced mouse lung tissue treated with AS61-ODN showed a specific reduction in collagen expression and fibrosis. Conclusion: Human type I collagen antisense oligodeoxynucleotides (AS60- ODN, a 20 mer), which is 99 percent homologous with mouse AS61-ODN, might be useful as a potential therapeutic agent to treat patients with pulmonary fibrosis.
Risk Factors at Birth for Permanent Obstetric Brachial Plexus Injury and Associated Osseous Deformities
Rahul K. Nath,Nirupama Kumar,Meera B. Avila,Devin K. Nath,Sonya E. Melcher,Mitchell G. Eichhorn,Chandra Somasundaram
ISRN Pediatrics , 2012, DOI: 10.5402/2012/307039
Abstract: Purpose. To examine the most prevalent risk factors found in patients with permanent obstetric brachial plexus injury (OBPI) to identify better predictors of injury. Methods. A population-based study was performed on 241 OBPI patients who underwent surgical treatment at the Texas Nerve and Paralysis Institute. Results. Shoulder dystocia (97%) was the most prevalent risk factor. We found that 80% of the patients in this study were not macrosomic, and 43% weighed less than 4000?g at birth. The rate of instrument use was 41% , which is 4-fold higher than the 10% predicted for all vaginal deliveries in the United States. Posterior subluxation and glenoid version measurements in children with no finger movement at birth indicated a less severe shoulder deformity in comparison with those with finger movement. Conclusions. The average birth weight in this study was indistinguishable from the average birth weight reported for all brachial plexus injuries. Higher birth weight does not, therefore, affect the prognosis of brachial plexus injury. We found forceps/vacuum delivery to be an independent risk factor for OBPI, regardless of birth weight. Permanently injured patients with finger movement at birth develop more severe bony deformities of the shoulder than patients without finger movement. 1. Introduction The incidence of obstetric brachial plexus injury (OBPI) is about 1.51 [1] per 1000 live births in the United States and reports vary from 0.38 [2] to 5.8 [3] per 1000 live births. Many of these injuries are transient; however, most of the OBPI patients never recover full function and develop permanent injuries [2, 4, 5]. In reports conducted by pediatricians and specialists, with follow-up times greater than 3 years, the reported proportion of injuries that remain permanent varies from 50 to 90% [6–8]. Risk factors for injury include shoulder dystocia, macrosomia (defined as birth weight greater than 4500?g [9–12]) instrument-assisted delivery, and downward traction of the fetal head [1, 7, 8]. Yet in a database search of over 11 million births, it was found that most children with neonatal brachial plexus palsy did not have known risk factors [1]. In obstetrics, presentation of shoulder dystocia is often emergent because the reported risk factors for its occurrence are not good predictors of it [13, 14]. Therefore we seek to examine the most prevalent risk factors found in a population of patients with permanent OBPI that necessitated surgical treatment to attempt to identify better predictors of injury and to elucidate the pathophysiology of OBPI.
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