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Raju S, Singhi PK, Somashekar V, Ajari A, Chidambaram M. Long-Term Outcomes of Gastrocnemius V-Y Plasty Gastrosoleus Fascial Turndown Flap for Chronic Tendo-achilles Injuries with Complex Gap (Kuwada Type IV Injuries). Indian J Orthop 2021; 56:421-428. [PMID: 35251505 PMCID: PMC8854614 DOI: 10.1007/s43465-021-00475-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/31/2021] [Indexed: 02/04/2023]
Abstract
INTRODUCTION The Achilles tendon is one of the strongest and most ruptured tendons; with no appropriate treatment it either heals in elongation or gap nonunion. Management of such chronic tears is critical and several procedures have been described. Complex gaps of over 6-8 cm need a combination technique. PURPOSE OF STUDY To assess the long-term functional outcome of surgical technique of combined gastrosoleus turndown flap augmented with V-Y plasty for chronic tendoachilles tear with a complex gap of over 8 cm. MATERIALS AND METHODS We retrospectively analyzed all the patients who were operated for tendoachilles tears from 2013 to 2018 and selected 12 patients who had a gap of 8 cm. Demographic details, history, clinical and radiological findings, post-op follow-up were collected from hospital database. The acute, open, chronic tears with gap of < 8 cm, peripheral vascular diseases were excluded. All the procedures were done by senior surgeon using combined technique of gastrosoleus turndown flap with V-Y plasty. Functional outcome was assessed using modified Rupp score, calf diameter and VAS scoring system at latest follow-up of the patient. RESULTS Assessing increase in calf diameter did objective analysis, average of 2.2 cm was regained which was statistically significant using paired T test. Each patient regained average 10° of dorsiflexion. Two patients had terminal 10° restriction of plantar flexion. All patients were able to do heel raise and single leg stance for at least 30 s. Subjective assessments done using modified Rupp score, five patients had excellent and seven patients had good outcome. Mean VAS for pain was 1.5 (1-3) and VAS for satisfaction was 7.5 (6-9). All patients returned to their pre-injury functional status. CONCLUSION Combined surgical technique of gastrosoleus turndown flap augmentation with V-Y plasty for repairing complex defects in chronic achilles tendon tears is a fair option with satisfactory functional outcome and fewer complications. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s43465-021-00475-6.
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Affiliation(s)
- Sivakumar Raju
- Preethi Hospitals Pvt. Ltd., 50 Melur Main Road, Uthangudi, Madurai, Tamilnadu 625107 India
| | - Prahalad Kumar Singhi
- Preethi Hospitals Pvt. Ltd., 50 Melur Main Road, Uthangudi, Madurai, Tamilnadu 625107 India
| | - V. Somashekar
- Preethi Hospitals Pvt. Ltd., 50 Melur Main Road, Uthangudi, Madurai, Tamilnadu 625107 India
| | - Ashutosh Ajari
- Shoulder and Sports Injuries Department, Sancheti Hospital, Pune, India
| | - M. Chidambaram
- Department of Orthopaedics, Preethi Hospitals Pvt. Ltd., Madurai, India
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Liju S, Chidambaram M, Mohan V, Radha V. Impact of type 2 diabetes variants identified through genome-wide association studies in early-onset type 2 diabetes from South Indian population. Genomics Inform 2020; 18:e27. [PMID: 33017871 PMCID: PMC7560451 DOI: 10.5808/gi.2020.18.3.e27] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 05/26/2020] [Indexed: 12/14/2022] Open
Abstract
The prevalence of early-onset type 2 diabetes (EOT2D) is increasing in Asian countries. Genome-wide association studies performed in European and various other populations have identified associations of numerous variants with type 2 diabetes in adults. However, the genetic component of EOT2D which is still unexplored could have similarities with late-onset type 2 diabetes. Here in the present study we aim to identify the association of variants with EOT2D in South Indian population. Twenty-five variants from 18 gene loci were genotyped in 1,188 EOT2D and 1,183 normal glucose tolerant subjects using the MassARRAY technology. We confirm the association of the HHEX variant rs1111875 with EOT2D in this South Indian population and also the association of CDKN2A/2B (rs7020996) and TCF7L2 (rs4506565) with EOT2D. Logistic regression analyses of the TCF7L2 variant rs4506565(A/T), showed that the heterozygous and homozygous carriers for allele ‘T’ have odds ratios of 1.47 (95% confidence interval [CI], 1.17 to 1.83; p = 0.001) and 1.65 (95% CI, 1.18 to 2.28; p = 0.006) respectively, relative to AA homozygote. For the HHEX variant rs1111875 (T/C), heterozygous and homozygous carriers for allele ‘C’ have odds ratios of 1.13 (95% CI, 0.91 to 1.42; p = 0.27) and 1.58 (95% CI, 1.17 to 2.12; p = 0.003) respectively, relative to the TT homozygote. For CDKN2A/2B variant rs7020996, the heterozygous and homozygous carriers of allele ‘C’ were protective with odds ratios of 0.65 (95% CI, 0.51 to 0.83; p = 0.0004) and 0.62 (95% CI, 0.27 to 1.39; p = 0.24) respectively, relative to TT homozygote. This is the first study to report on the association of HHEX variant rs1111875 with EOT2D in this population.
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Affiliation(s)
- Samuel Liju
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai 600086, India
| | - Manickam Chidambaram
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai 600086, India
| | - Viswanathan Mohan
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai 600086, India.,Dr. Mohan's Diabetes Specialties Centre, ICMR Centre for Diabetes Advanced Research and WHO Collaborating Centre for Non-communicable Diseases Prevention and Control, Chennai 600086, India
| | - Venkatesan Radha
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai 600086, India
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Narasimha Reddy S, Chidambaram M. Model identification of critically damped second order plus time delay systems. Chem Ind 2019. [DOI: 10.1080/00194506.2019.1629842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- S. Narasimha Reddy
- Department of Chemical Engineering, National Institute of Technology, Warangal, India
| | - M. Chidambaram
- Department of Chemical Engineering, National Institute of Technology, Warangal, India
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Affiliation(s)
- Saxena Nikita
- Department of Chemical Engineering, Indian Institute of Technology, Madras, Chennai 600036, India
| | - M. Chidambaram
- Department of Chemical Engineering, Indian Institute of Technology, Madras, Chennai 600036, India
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Besta CS, Chidambaram M. BLT Method for PI Controllers of Unstable Systems. Indian Chemical Engineer 2018. [DOI: 10.1080/00194506.2016.1270779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Chandra Shekar Besta
- Process Control Group, Department of Chemical Engineering, Indian Institute of Technology, Madras, Chennai 600 036, India
| | - Manickam Chidambaram
- Process Control Group, Department of Chemical Engineering, Indian Institute of Technology, Madras, Chennai 600 036, India
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Chidambaram M, Ram V D. SSGM Based Multivariable Control of Unstable Non-Square Systems. Chemical Product and Process Modeling 2018. [DOI: 10.1515/cppm-2017-0033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractDavison (1976) proposed a method to design controllers for multivariable systems using the knowledge of only the Steady-State Gain Matrix (SSGM) of the system. In the present work, Davison's method is suitably modified to design controllers for unstable non-square multivariable systems. A single-stage multivariable PI controller is designed using the SSGM. Simulation results show that the overshoots of the closed loop responses are larger, hence a two-stage P-PI control system is proposed. For the proposed two- stage design (i) the system is first stabilized by a simple proportional controller matrix designed based on SSGM using modified Davison's method (1976). (ii) Diagonal PI controllers are designed for this stabilized system based on gain matrix. Simulation studies are carried out to compare the closed loop performance of the single stage multivariable PI control system with that of the two-stage control system (inner loop centralized P controllers and outer loop diagonal PI controllers). A method to identify the steady state gain matrix of a non-square multivariable (SSGM) unstable system under closed loop control is presented. The effect of disturbances and measurement noise on the identification of SSGM is also discussed.
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Affiliation(s)
- Simi Santosh
- Department of Chemical Engineering, Manipal University Dubai Campus, Dubai, UAE
| | - Manickam Chidambaram
- Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai, India
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Besta CS, Chidambaram M. Design of Centralized PI Controllers by Synthesis Method for TITO Systems. Indian Chemical Engineer 2017. [DOI: 10.1080/00194506.2015.1116961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Chandra Shekar Besta
- Department of Chemical Engineering, Indian Institute of Technology, Chennai 600 036, India
| | - Manickam Chidambaram
- Department of Chemical Engineering, Indian Institute of Technology, Chennai 600 036, India
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Affiliation(s)
- V. Dhanya Ram
- Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai, India
| | - M. Chidambaram
- Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai, India
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Sivakumar R, SomaSheker V, Shingi PK, Vinoth T, Chidambaram M. Treatment of Stiff Elbow in Young Patients with Interpositional Arthroplasty for Mobility: Case Series. J Orthop Case Rep 2017; 6:49-52. [PMID: 28164052 PMCID: PMC5288624 DOI: 10.13107/jocr.2250-0685.566] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
INTRODUCTION The elbow is a complex joint involving many articulations and complex biomechanics come into play. Elbow motion is crucial to upper limb movement that loss of 50% of elbow function equals to loss of 80% of upper extremity global function. Restoring movement and stability is challenging to the surgeon while treating a stiff elbow. Unlike other arthroplasties of hip and knee, total elbow arthroplasty (TEA) may not be a primary treatment. Interpositional arthroplasty (IPA) can be considered a viable option in posttraumatic arthritis of elbow in young patients. CASE REPORT We report two cases of interpositional arthroplasties done in young patients secondary to posttraumatic event. The first case is 22-year-old female with a history of stiff elbow following a posttraumatic event 3 years back and the second case is 24-year-old male laborer with stiff elbow following trauma more the 10 years back for which he took native treatment. In both the cases through posterior approach to the elbow, we did osteolysis and prepared fascia lata grafts are interpositioned over the recreated articular surfaces. Both the patients in the follow-up have a good range of motion, stability and are satisfied. CONCLUSION IPA is a good treatment option in young patients with posttraumatic arthritis. Elbow instability, fascia rupture, thigh pain, and hernia are the problems of IPA. IPA to TEA transition is possible.
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Affiliation(s)
- R Sivakumar
- Department of Orthopaedics, Preethi Institute of Orthopaedics and Research, Preethi Hospitals (Pvt) Limited, Madurai, Tamil Nadu, India
| | - V SomaSheker
- Department of Orthopaedics, Preethi Institute of Orthopaedics and Research, Preethi Hospitals (Pvt) Limited, Madurai, Tamil Nadu, India
| | - Prahalad Kumar Shingi
- Department of Orthopaedics, Preethi Institute of Orthopaedics and Research, Preethi Hospitals (Pvt) Limited, Madurai, Tamil Nadu, India
| | - T Vinoth
- Department of Orthopaedics, Preethi Institute of Orthopaedics and Research, Preethi Hospitals (Pvt) Limited, Madurai, Tamil Nadu, India
| | - M Chidambaram
- Department of Orthopaedics, Preethi Institute of Orthopaedics and Research, Preethi Hospitals (Pvt) Limited, Madurai, Tamil Nadu, India
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Affiliation(s)
- Chandra Shekar Besta
- Department of Chemical Engineering, Indian Institute of Technology – Madras, 600 036 Chennai, India
| | - Manickam Chidambaram
- Department of Chemical Engineering, Indian Institute of Technology – Madras, 600 036 Chennai, India
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Sivakumar R, Mohideen MG, Chidambaram M, Vinoth T, Singhi PK, Somashekar V. Management of Large Bone Defects in Diaphyseal Fractures by Induced Membrane Formation by Masquelet's Technique. J Orthop Case Rep 2017; 6:59-62. [PMID: 28116272 PMCID: PMC5245941 DOI: 10.13107/jocr.2250-0685.508] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Introduction: Management of the large gap in long bone fractures is a challenging problem after compound injuries. A novel technique called as Masquelet’s technique of “induced membrane formation”, is used to bridge a gap of more than 5 cm using bone cement as a spacer in first stage and autologous cancellous bone graft to fill the gap in second stage. Case presentation: We present two different and difficult cases with bone defects after open injuries associated with long bone fractures in this paper. First case is a 50-year-old lady with grade IIIa open fracture right distal femur with intra-articular extension and bone loss. She underwent wound debriment, stabilization of the fracture with locking compression plate along with antibiotic cement spacer, which is removed latter and underwent bone grafting. Another is a 15-year-old boy with open grade IIIb fracture tibia and fibula (mid-distal third junction) of right leg, wound debridement and ankle spanning triangular external fixation was applied on same day and after two months, external fixation was removed due to florid infection and plaster of Paris was applied. Instead of the tedious and demanding treatment options like Ilizarov, a new technique described by Masquelet is used here. It uses bone cement as a spacer to fill the cavity to form pseudo-membrane around it and in the second stage autologous cancellous bone graft fills the gap of even more than 5 cm, to achieve union. Conclusion: The membrane also secretes vascular and osteo-inductive factors to stimulate bone regeneration and also prevents resorption of the bone graft and achieves early fracture healing avoiding tedious options like bone transport in external fixator. By this two staged technique, union occurred clinically and radiologically in these two cases.
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Affiliation(s)
- R Sivakumar
- Department of Orthopaedics, Preethi Hospitals Pvt Ltd, Madurai. 625007, India
| | - M Gulam Mohideen
- Department of Orthopaedics, Thanjavur medical college, Thanjavur, India
| | - M Chidambaram
- Department of Orthopaedics, Preethi Hospitals Pvt Ltd, Madurai. 625007, India
| | - T Vinoth
- Department of Orthopaedics, Preethi Hospitals Pvt Ltd, Madurai. 625007, India
| | | | - V Somashekar
- Department of Orthopaedics, Preethi Hospitals Pvt Ltd, Madurai. 625007, India
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Chidambaram M, Liju S, Saboo B, Sathyavani K, Viswanathan V, Pankratz N, Gross M, Mohan V, Radha V. Replication of genome-wide association signals in Asian Indians with early-onset type 2 diabetes. Acta Diabetol 2016; 53:915-923. [PMID: 27488727 DOI: 10.1007/s00592-016-0889-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 07/12/2016] [Indexed: 01/22/2023]
Abstract
AIMS To evaluate the association of 87 genetic variants previously associated with type 2 diabetes mellitus (T2DM) in genome-wide association studies of populations of European ancestry in an Asian Indian population with early-onset type 2 diabetes mellitus (EOT2DM). METHODS The study groups comprised of 877 type 2 diabetes individuals, 436 individuals with EOT2DM (age at diagnosis below 35 years), 441 individuals with older T2DM (diagnosis at 35 years or greater) and controls with normal glucose tolerance (NGT) (n = 400 younger than 35 years; n = 438 older than 35 years). The participants were genotyped for 87 SNPs from 44 genes and 27 intergenic loci. Associations were tested using logistic regression. RESULTS All the variants in TCF7L2 and CDKN2A/2B showed study-wide significance (p < 1.4 × 10-4) with T2DM, but only rs7903146, rs12243326, rs12255372 of TCF7L2 and rs7020996 of CDKN2A/2B showed study-wide significance (p < 1.4 × 10-4) with EOT2DM in this population. In addition, an intergenic SNP on chromosome 1 (rs10493685) was also shown to be study-wide significant (p = 7.1 × 10-6). Several additional SNPs previously associated with T2DM reached borderline significance in this study, but may have been limited by relatively low sample numbers. Various other SNPs of T2DM were not associated with EOT2DM. CONCLUSIONS Some of the variants in TCF7L2 and CDKN2A/2B associated with T2DM are associated with EOT2DM as well. An intergenic SNP on chromosome 1p31 showed association only with early-onset T2DM in this Asian Indian population. The lack of association with many other SNPs of T2DM may be a reflection of the lack of power of the study, sample size, differences in the frequencies of genetic polymorphisms in different ethnic groups, effect sizes, as well as ancestral differences in pattern of LD between the genetic variants involved in early- and late-onset T2DM.
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Affiliation(s)
- Manickam Chidambaram
- Madras Diabetes Research Foundation, 4, Conran Smith Road, Gopalapuram, Chennai, 600 086, India
- Division of Cardiovascular Research, Sidra Medical and Research Center, Doha, Qatar
| | - Samuel Liju
- Madras Diabetes Research Foundation, 4, Conran Smith Road, Gopalapuram, Chennai, 600 086, India
| | - Banshi Saboo
- Diabetologist and Endocrine and Metabolic Physician at Diabetes Care and Hormone Clinic, Ahmedabad, Gujarat, India
| | - Kumpatla Sathyavani
- M.V. Hospital for Diabetes and Prof. M. Viswanathan Diabetes Research Centre, Chennai, Tamil Nadu, India
| | - Vijay Viswanathan
- M.V. Hospital for Diabetes and Prof. M. Viswanathan Diabetes Research Centre, Chennai, Tamil Nadu, India
| | - Nathan Pankratz
- Department of Laboratory Medicine Pathology, Medical School University of Minnesota, Minneapolis, MN, USA
| | - Myron Gross
- Department of Laboratory Medicine Pathology, Medical School University of Minnesota, Minneapolis, MN, USA
| | - Viswanathan Mohan
- Madras Diabetes Research Foundation, 4, Conran Smith Road, Gopalapuram, Chennai, 600 086, India
- Dr. Mohan's Diabetes Specialities Centre, WHO Collaborating Centre for Non-Communicable Diseases Prevention and Control, IDF Centre of Education, Chennai, India
| | - Venkatesan Radha
- Madras Diabetes Research Foundation, 4, Conran Smith Road, Gopalapuram, Chennai, 600 086, India.
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Santosh S, Chidambaram M. A simple method of tuning parallel cascade controllers for unstable FOPTD systems. ISA Trans 2016; 65:475-486. [PMID: 27625173 DOI: 10.1016/j.isatra.2016.08.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Revised: 04/10/2016] [Accepted: 08/13/2016] [Indexed: 06/06/2023]
Abstract
A simple method is proposed to design parallel cascade controllers for open loop unstable processes. A proportional (P)controller is considered for the secondary loop and a proportional integral (PI) controller is considered for the primary loop (P/PI control configuration). Coefficients of the corresponding powers of s (Laplace variable), in the numerator is matched with the coefficients of the corresponding powers of s in the denominator of a closed loop transfer function for a servo problem. Three simulation case studies are considered in this paper. The first case involves a stable secondary loop process and an unstable primary process, the second case involves both unstable primary and secondary processes and the third one, a simulation application to a nonlinear bioreactor model equations. For comparison purposes, P/PI controller design is also carried out by improved simultaneous relay autotuning method, synthesis method and minimizing ISE criterion method. It is found that the proposed method gives a better performance. Robust stability analysis using the complimentary sensitivity function is carried out. The present method is found to be more robust.
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Affiliation(s)
- Simi Santosh
- Department of Chemical Engineering, Indian Institute of Technology, Madras, India
| | - M Chidambaram
- Department of Chemical Engineering, Indian Institute of Technology, Madras, India.
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Bodhini D, Chidambaram M, Liju S, Revathi B, Laasya D, Sathish N, Kanthimathi S, Ghosh S, Anjana RM, Mohan V, Radha V. Association of rs11643718 SLC12A3 and rs741301 ELMO1 Variants with Diabetic Nephropathy in South Indian Population. Ann Hum Genet 2016; 80:336-341. [PMID: 27699784 DOI: 10.1111/ahg.12174] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 08/18/2016] [Accepted: 09/07/2016] [Indexed: 11/30/2022]
Abstract
This study reports on the association of genetic variants selected from previous genome-wide association studies for type 2 diabetic nephropathy in south Indians. Eight variants were genotyped in 601 type 2 diabetic subjects without nephropathy (DM) and 583 type 2 diabetic subjects with nephropathy (DN) by MassARRAY. The minor allele frequencies of rs11643718 SLC12A3 variant and rs741301 ELMO1 variant were significantly different between DM and DN groups (P = 0.029 and 0.016, respectively). A combined analysis showed that the subjects carrying the risk genotypes of both these variants (GG of rs11643718 + AG/AA of rs741301) had a significant association with DN with an odds ratio [adjusted for age, sex, Body Mass Index (BMI), HbA1c, and systolic Blood Pressure (BP)] of 1.73 (1.30-2.30, P = 1.72 × 10-4 ) as compared to subjects carrying all other genotype combinations. This is the first study to report a significant association of the SLC12A3 rs11643718 and ELMO1 rs741301 (Single nucleotide Polymorphism) SNPs with diabetic nephropathy in south Indians.
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Affiliation(s)
- Dhanasekaran Bodhini
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai, India
| | - Manickam Chidambaram
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai, India
| | - Samuel Liju
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai, India
| | - Balakannan Revathi
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai, India
| | - Dhandapani Laasya
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai, India
| | - Natarajan Sathish
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai, India
| | - Sekar Kanthimathi
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai, India
| | | | - Ranjit Mohan Anjana
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai, India.,Diabetes Specialities Centre, WHO Collaborating Centre for Non-Communicable Diseases Prevention & Control, IDF Centre of Education, Chennai, India
| | - Viswanathan Mohan
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai, India.,Diabetes Specialities Centre, WHO Collaborating Centre for Non-Communicable Diseases Prevention & Control, IDF Centre of Education, Chennai, India
| | - Venkatesan Radha
- Department of Molecular Genetics, Madras Diabetes Research Foundation, Chennai, India
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Dhanya Ram V, Chidambaram M. Identification of Centralised Controlled Multivariable Systems. Indian Chemical Engineer 2016. [DOI: 10.1080/00194506.2015.1029285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Hazarika S, Chidambaram M. Static Decouplers with P-PI Dual Loop Controllers for Unstable System. Indian Chemical Engineer 2016. [DOI: 10.1080/00194506.2015.1006146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Thanga Mani N, Chidambaram M. Discrimination of Models for Autocatalytic Polymerization Reactions by Periodic Operation. Indian Chemical Engineer 2016. [DOI: 10.1080/00194506.2016.1157918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Kumar RS, K.Singhi P, Chidambaram M, Kakkandki K. Case Report of Two Cases of Patella Subacute Osteomyelitis in Diabetic Women A Rare Entity. J Orthop Case Rep 2016; 6:13-15. [PMID: 27703930 PMCID: PMC5040560 DOI: 10.13107/jocr.2250-0685.408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
INTRODUCTION Patella osteomyelitis is a rare entity in adults. Most often it is seen in children of five to twelve years of age because of its unique ossification and vascularity. Immuno compromised states like HIV, tuberculosis, intravenous drug abuse and trauma have been predisposing factors for adult patellar osteomyelitis. We report two cases of patellar osteomyelitis in adult diabetic women with uncontrolled glycemic levels and having no previous history of any trauma or systemic infection. CASE REPORT A 43-year-old diabetic woman presented with complaints of left knee pain and swelling with no history of trauma. On examination, pointed tenderness was present over anterior aspect of patella with patellar grind test positive. Radiography and MRI revealed solitary well circumscribed patellar cyst. Lateral chondral blisters were noted while doing arthroscopy and secretions oozed out on puncturing. Curettage was carried out for the same. Culture and sensitivity revealed no growth and the patient was prescribed antibiotics for 6 weeks. Second case was a 46-year-old diabetic lady with similar presentation. MRI additionally showed abscess in intermuscular plains around knee joint. An aspirated fluid was negative for growth of organisms. Knee arthrotomy and curettage of patellar sinus tracts was done with evacuation of intramuscular abscess. Antibiotics were given for 6 weeks. Both patients had complete relief of symptoms. CONCLUSION Patella osteomyelitis in adults is very rare. In patients with uncontrolled diabetes, vague anterior knee pain, elevated ESR and CRP, one should keep patellar subacute osteomyelitis as a differential diagnosis which can be further confirmed by X-ray, MRI or bone scan. An appropriate early treatment with antibiotics and surgical intervention can give a satisfactory result.
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Affiliation(s)
- R. Siva Kumar
- Department of Orthopaedics, Preethi Hospitals Pvt Ltd., Madurai, Tamilnadu, India
| | - Prahalad K.Singhi
- Department of Orthopaedics, Preethi Hospitals Pvt Ltd., Madurai, Tamilnadu, India
| | - M. Chidambaram
- Department of Orthopaedics, Preethi Hospitals Pvt Ltd., Madurai, Tamilnadu, India
| | - Kiran Kakkandki
- Department of Orthopaedics, Preethi Hospitals Pvt Ltd., Madurai, Tamilnadu, India
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Affiliation(s)
- Saxena Nikita
- Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India
| | - M. Chidambaram
- Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India
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Affiliation(s)
- Saxena Nikita
- Department of Chemical Engineering, Indian Institute of Technology-Madras, Chennai 600036, India
| | - M. Chidambaram
- Department of Chemical Engineering, Indian Institute of Technology-Madras, Chennai 600036, India
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Ram VD, Karlmarx A, Chidambaram M. Identification of Unstable Second-order Transfer Function Model with a Zero by Optimization Method. Indian Chemical Engineer 2016. [DOI: 10.1080/00194506.2014.990240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Sivakumar R, Singhi PK, Chidambaram M, Somashekar V, Thangamani V. A Sub-acute Septic Arthritis of the Knee; a Sequelae to Thorn Prick Injury of Patella: A Case Report. J Orthop Case Rep 2016; 6:100-103. [PMID: 28507977 PMCID: PMC5404149 DOI: 10.13107/jocr.2250-0685.654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
INTRODUCTION Sub-acute septic arthritis of knee following a thorn prick injury to patella is an uncommon condition and seen in active playful children. The child may be afraid to narrate the incident to their parents or examining doctor, so a high index of suspicion is must. The delayed presentation is inevitable. Early synovitis due to the organic biological foreign body may progress to septic arthritis, if untreated may result in knee stiffness or chronic osteomyelitis of patella. CASE REPORT We report a case of thorn prick injury to the left patella in an 8-years-old boy who neglected the incident of thorn prick while playing with his peer group 10 days ago and presented with features of sub-acute septic arthritis. He was treated by arthrotomy, double inspection of the patella, removal of foreign body, synovectomy, lavage, antibiotics, and aggressive rehabilitation with an excellent outcome. CONCLUSION Sub-acute synovitis in active playful children should raise the suspicion of thorn prick even though no proper history is explained. Organic foreign body from plant materials is radiolucent and easily missed. High suspicion and timely surgical intervention, double inspection during arthrotomy identifies the foreign body. Once removed, with proper antibiotic and physiotherapy protocol followed has an excellent outcome.
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Affiliation(s)
- R Sivakumar
- Department of Orthopaedics, Preethi Hospitals Pvt. Ltd., Madurai, Tamil Nadu, India
| | - Prahalad Kumar Singhi
- Department of Orthopaedics, Preethi Hospitals Pvt. Ltd., Madurai, Tamil Nadu, India,Address of Correspondence Dr. Prahalad Kumar Singhi, Department of Orthopaedics, Preethi Institute of Orthopaedics and Research (PRIOR), Preethi Hospitals Pvt. Limited, 120 Feet Road, Madurai, Tamil Nadu, India. E-mail:
| | - M Chidambaram
- Department of Orthopaedics, Preethi Hospitals Pvt. Ltd., Madurai, Tamil Nadu, India
| | - V Somashekar
- Department of Orthopaedics, Preethi Hospitals Pvt. Ltd., Madurai, Tamil Nadu, India
| | - Vinoth Thangamani
- Department of Orthopaedics, Preethi Hospitals Pvt. Ltd., Madurai, Tamil Nadu, India
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Bodhini D, Chidambaram M, Liju S, Prakash VG, Gayathri V, Shanthirani CS, Ranjith U, Anjana RM, Mohan V, Radha V. Association of TCF7L2 Polymorphism with Diabetic Nephropathy in the South Indian Population. Ann Hum Genet 2015; 79:373-379. [PMID: 26155736 DOI: 10.1111/ahg.12122] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 04/13/2015] [Accepted: 04/27/2015] [Indexed: 01/26/2023]
Abstract
The transcription factor 7-like 2 (TCF7L2) gene plays a significant role in the development of type 2 diabetes and diabetic nephropathy. The aim of this study was to investigate the association of TCF7L2 rs12255372 (G/T)polymorphism with type 2 diabetic nephropathy in the South Indian population. A total of 2102 subjects, 927 normal glucose tolerant (NGT) subjects, 598 type 2 diabetic subjects without nephropathy (DM), and 577 type 2 diabetic subjects with nephropathy (DN) were genotyped by MassARRAY. As compared to the NGT group, the odds ratio (adjusted for age, sex, BMI, HbA1c, and systolic BP) computed for the GT/TT genotype taking the GG genotype as reference was found to be 2.02 (95% CI: 1.16-3.51, p = 0.013) for DN and 1.94 (95% CI: 1.36-2.78, p = 0.0002) for DM. The genotype frequency was not significantly different between the DM and DN groups. In conclusion, the rs12255372 polymorphism in the TCF7L2 gene is associated with type 2 diabetes and DN but its association with DN is mediated through diabetes.
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Affiliation(s)
| | - Manickam Chidambaram
- Madras Diabetes Research Foundation, Chennai, India.,Qatar Cardiovascular Research Centre, Qatar
| | - Samuel Liju
- Madras Diabetes Research Foundation, Chennai, India
| | | | | | | | - Unnikrishnan Ranjith
- Dr. Mohan's Diabetes Specialities Centre, WHO Collaborating Centre for Non-Communicable Diseases Prevention & Control, IDF Centre of Education, Chennai, India
| | - Ranjit M Anjana
- Madras Diabetes Research Foundation, Chennai, India.,Dr. Mohan's Diabetes Specialities Centre, WHO Collaborating Centre for Non-Communicable Diseases Prevention & Control, IDF Centre of Education, Chennai, India
| | - Viswanathan Mohan
- Madras Diabetes Research Foundation, Chennai, India.,Dr. Mohan's Diabetes Specialities Centre, WHO Collaborating Centre for Non-Communicable Diseases Prevention & Control, IDF Centre of Education, Chennai, India
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Kanthimathi S, Chidambaram M, Liju S, Bhavadharini B, Bodhini D, Prakash VG, Amutha A, Bhavatharini A, Anjana RM, Mohan V, Radha V. Identification of Genetic Variants of Gestational Diabetes in South Indians. Diabetes Technol Ther 2015; 17:462-7. [PMID: 25723968 DOI: 10.1089/dia.2014.0349] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND This study examined the association in a South Indian population with gestational diabetes mellitus (GDM) of type 2 diabetes risk variants that have previously conferred susceptibility to GDM in other populations. SUBJECTS AND METHODS The study groups comprised 518 women with GDM and 910 pregnant women with normal glucose tolerance (NGT). Women with GDM were recruited from a tertiary diabetes center in Chennai, in south India, and NGT women were selected from antenatal clinics also in Chennai. Genomic DNA was isolated from whole blood using the phenol chloroform method. Twelve previously reported GDM-associated single nucleotide polymorphisms (SNPs) in or near nine loci were genotyped using the MassARRAY™ system (Sequenom, San Diego, CA). RESULTS Among the 12 SNPs genotyped, 11 SNPs were in Hardy-Weinberg equilibrium and had a call rate of >95%. Of the 11 SNPs previously associated with GDM in other populations, significant association was observed only with the rs7754840 and rs7756992 SNPs of the CDK5 regulatory subunit associated protein 1-like 1 (CDKAL1) gene in this population. The minor alleles of the SNPs rs7754840 and rs7756992 showed significant susceptibility to GDM with an odds ratio of 1.34 (95% confidence interval, 1.12-1.60; P = 0.0013) and 1.45 (95% confidence interval, 1.21-1.72; P = 0.00004), respectively. CONCLUSIONS The rs7754840 and rs7756992 SNPs of the CDKAL1 gene were found to be associated with GDM in this south Indian population. This is the first study describing genetic susceptibility of GDM in Asian Indians.
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Affiliation(s)
| | | | - Samuel Liju
- 1 Madras Diabetes Research Foundation , Chennai, India
| | | | | | | | | | | | - Ranjit Mohan Anjana
- 1 Madras Diabetes Research Foundation , Chennai, India
- 2 Dr. Mohan's Diabetes Specialities Centre, WHO Collaborating Centre for Non-Communicable Diseases Prevention & Control, IDF Centre of Education , Chennai, India
| | - Viswanathan Mohan
- 1 Madras Diabetes Research Foundation , Chennai, India
- 2 Dr. Mohan's Diabetes Specialities Centre, WHO Collaborating Centre for Non-Communicable Diseases Prevention & Control, IDF Centre of Education , Chennai, India
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Dhanya Ram V, Chidambaram M. Simple method of designing centralized PI controllers for multivariable systems based on SSGM. ISA Trans 2015; 56:252-260. [PMID: 25530257 DOI: 10.1016/j.isatra.2014.11.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 10/26/2014] [Accepted: 11/29/2014] [Indexed: 06/04/2023]
Abstract
A method is given to design multivariable PI/PID controllers for stable and unstable multivariable systems. The method needs only the steady state gain matrix (SSGM). The method is based on the static decoupler design followed by SISO PI/PID controllers design and combining the resulted decoupler and the diagonal PI(D) controllers as the centralized controllers. The result of the present method is shown to be equivalent to the empirical method proposed by Davison EJ. Multivariable tuning regulators: the feed-forward and robust control of general servo-mechanism problem. IEEE Trans Autom Control 1976;21:35-41. Three simulation examples are given. The performance of the controllers is compared with that of the reported centralized controller based on the multivariable transfer function matrix.
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Affiliation(s)
- V Dhanya Ram
- Dept of Chemical Engineering, Indian Institute of Technology, Madras 600036, India
| | - M Chidambaram
- Dept of Chemical Engineering, Indian Institute of Technology, Madras 600036, India.
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Santosh S, Chidambaram M. Tuning of Proportional Integral Derivative Controllers for Critically Damped Second-Order Plus Time Delay Systems. Chem Ind 2014. [DOI: 10.1080/00194506.2014.975760] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Kumar VV, Rao VR, Chidambaram M. Centralised Multi-input Multi-output Controllers for Non-minimum Phase Systems. Indian Chemical Engineer 2014. [DOI: 10.1080/00194506.2014.903622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Affiliation(s)
- Sukanya Hazarika
- Department of Chemical Engineering, Indian Institute Of Technology Madras, Chennai 600 036, India
| | - M. Chidambaram
- Department of Chemical Engineering, Indian Institute Of Technology Madras, Chennai 600 036, India
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Affiliation(s)
- Deepthi Sen
- Dept. of Chemical Engineering; Indian Institute of Technology Madras; Chennai Tamil Nadu 600036 India
| | - Dilshad Raihan
- Dept. of Mechanical Engineering; Indian Institute of Technology Madras; Chennai Tamil Nadu 600036 India
| | - M. Chidambaram
- Dept. of Chemical Engineering; Indian Institute of Technology Madras; Chennai Tamil Nadu 600036 India
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Mahajan A, Go MJ, Zhang W, Below JE, Gaulton KJ, Ferreira T, Horikoshi M, Johnson AD, Ng MCY, Prokopenko I, Saleheen D, Wang X, Zeggini E, Abecasis GR, Adair LS, Almgren P, Atalay M, Aung T, Baldassarre D, Balkau B, Bao Y, Barnett AH, Barroso I, Basit A, Been LF, Beilby J, Bell GI, Benediktsson R, Bergman RN, Boehm BO, Boerwinkle E, Bonnycastle LL, Burtt N, Cai Q, Campbell H, Carey J, Cauchi S, Caulfield M, Chan JCN, Chang LC, Chang TJ, Chang YC, Charpentier G, Chen CH, Chen H, Chen YT, Chia KS, Chidambaram M, Chines PS, Cho NH, Cho YM, Chuang LM, Collins FS, Cornelis MC, Couper DJ, Crenshaw AT, van Dam RM, Danesh J, Das D, de Faire U, Dedoussis G, Deloukas P, Dimas AS, Dina C, Doney AS, Donnelly PJ, Dorkhan M, van Duijn C, Dupuis J, Edkins S, Elliott P, Emilsson V, Erbel R, Eriksson JG, Escobedo J, Esko T, Eury E, Florez JC, Fontanillas P, Forouhi NG, Forsen T, Fox C, Fraser RM, Frayling TM, Froguel P, Frossard P, Gao Y, Gertow K, Gieger C, Gigante B, Grallert H, Grant GB, Grrop LC, Groves CJ, Grundberg E, Guiducci C, Hamsten A, Han BG, Hara K, Hassanali N, Hattersley AT, Hayward C, Hedman AK, Herder C, Hofman A, Holmen OL, Hovingh K, Hreidarsson AB, Hu C, Hu FB, Hui J, Humphries SE, Hunt SE, Hunter DJ, Hveem K, Hydrie ZI, Ikegami H, Illig T, Ingelsson E, Islam M, Isomaa B, Jackson AU, Jafar T, James A, Jia W, Jöckel KH, Jonsson A, Jowett JBM, Kadowaki T, Kang HM, Kanoni S, Kao WHL, Kathiresan S, Kato N, Katulanda P, Keinanen-Kiukaanniemi KM, Kelly AM, Khan H, Khaw KT, Khor CC, Kim HL, Kim S, Kim YJ, Kinnunen L, Klopp N, Kong A, Korpi-Hyövälti E, Kowlessur S, Kraft P, Kravic J, Kristensen MM, Krithika S, Kumar A, Kumate J, Kuusisto J, Kwak SH, Laakso M, Lagou V, Lakka TA, Langenberg C, Langford C, Lawrence R, Leander K, Lee JM, Lee NR, Li M, Li X, Li Y, Liang J, Liju S, Lim WY, Lind L, Lindgren CM, Lindholm E, Liu CT, Liu JJ, Lobbens S, Long J, Loos RJF, Lu W, Luan J, Lyssenko V, Ma RCW, Maeda S, Mägi R, Männisto S, Matthews DR, Meigs JB, Melander O, Metspalu A, Meyer J, Mirza G, Mihailov E, Moebus S, Mohan V, Mohlke KL, Morris AD, Mühleisen TW, Müller-Nurasyid M, Musk B, Nakamura J, Nakashima E, Navarro P, Ng PK, Nica AC, Nilsson PM, Njølstad I, Nöthen MM, Ohnaka K, Ong TH, Owen KR, Palmer CNA, Pankow JS, Park KS, Parkin M, Pechlivanis S, Pedersen NL, Peltonen L, Perry JRB, Peters A, Pinidiyapathirage JM, Platou CG, Potter S, Price JF, Qi L, Radha V, Rallidis L, Rasheed A, Rathman W, Rauramaa R, Raychaudhuri S, Rayner NW, Rees SD, Rehnberg E, Ripatti S, Robertson N, Roden M, Rossin EJ, Rudan I, Rybin D, Saaristo TE, Salomaa V, Saltevo J, Samuel M, Sanghera DK, Saramies J, Scott J, Scott LJ, Scott RA, Segrè AV, Sehmi J, Sennblad B, Shah N, Shah S, Shera AS, Shu XO, Shuldiner AR, Sigurđsson G, Sijbrands E, Silveira A, Sim X, Sivapalaratnam S, Small KS, So WY, Stančáková A, Stefansson K, Steinbach G, Steinthorsdottir V, Stirrups K, Strawbridge RJ, Stringham HM, Sun Q, Suo C, Syvänen AC, Takayanagi R, Takeuchi F, Tay WT, Teslovich TM, Thorand B, Thorleifsson G, Thorsteinsdottir U, Tikkanen E, Trakalo J, Tremoli E, Trip MD, Tsai FJ, Tuomi T, Tuomilehto J, Uitterlinden AG, Valladares-Salgado A, Vedantam S, Veglia F, Voight BF, Wang C, Wareham NJ, Wennauer R, Wickremasinghe AR, Wilsgaard T, Wilson JF, Wiltshire S, Winckler W, Wong TY, Wood AR, Wu JY, Wu Y, Yamamoto K, Yamauchi T, Yang M, Yengo L, Yokota M, Young R, Zabaneh D, Zhang F, Zhang R, Zheng W, Zimmet PZ, Altshuler D, Bowden DW, Cho YS, Cox NJ, Cruz M, Hanis CL, Kooner J, Lee JY, Seielstad M, Teo YY, Boehnke M, Parra EJ, Chambers JC, Tai ES, McCarthy MI, Morris AP. Genome-wide trans-ancestry meta-analysis provides insight into the genetic architecture of type 2 diabetes susceptibility. Nat Genet 2014; 46:234-44. [PMID: 24509480 PMCID: PMC3969612 DOI: 10.1038/ng.2897] [Citation(s) in RCA: 777] [Impact Index Per Article: 77.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Accepted: 01/17/2014] [Indexed: 11/18/2022]
Abstract
To further understanding of the genetic basis of type 2 diabetes (T2D) susceptibility, we aggregated published meta-analyses of genome-wide association studies (GWAS) including 26,488 cases and 83,964 controls of European, East Asian, South Asian, and Mexican and Mexican American ancestry. We observed significant excess in directional consistency of T2D risk alleles across ancestry groups, even at SNPs demonstrating only weak evidence of association. By following up the strongest signals of association from the trans-ethnic meta-analysis in an additional 21,491 cases and 55,647 controls of European ancestry, we identified seven novel T2D susceptibility loci. Furthermore, we observed considerable improvements in fine-mapping resolution of common variant association signals at several T2D susceptibility loci. These observations highlight the benefits of trans-ethnic GWAS for the discovery and characterisation of complex trait loci, and emphasize an exciting opportunity to extend insight into the genetic architecture and pathogenesis of human diseases across populations of diverse ancestry.
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Saxena R, Saleheen D, Been LF, Garavito ML, Braun T, Bjonnes A, Young R, Ho WK, Rasheed A, Frossard P, Sim X, Hassanali N, Radha V, Chidambaram M, Liju S, Rees SD, Ng DPK, Wong TY, Yamauchi T, Hara K, Tanaka Y, Hirose H, McCarthy MI, Morris AP, Basit A, Barnett AH, Katulanda P, Matthews D, Mohan V, Wander GS, Singh JR, Mehra NK, Ralhan S, Kamboh MI, Mulvihill JJ, Maegawa H, Tobe K, Maeda S, Cho YS, Tai ES, Kelly MA, Chambers JC, Kooner JS, Kadowaki T, Deloukas P, Rader DJ, Danesh J, Sanghera DK. Genome-wide association study identifies a novel locus contributing to type 2 diabetes susceptibility in Sikhs of Punjabi origin from India. Diabetes 2013; 62:1746-55. [PMID: 23300278 PMCID: PMC3636649 DOI: 10.2337/db12-1077] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
We performed a genome-wide association study (GWAS) and a multistage meta-analysis of type 2 diabetes (T2D) in Punjabi Sikhs from India. Our discovery GWAS in 1,616 individuals (842 case subjects) was followed by in silico replication of the top 513 independent single nucleotide polymorphisms (SNPs) (P < 10⁻³) in Punjabi Sikhs (n = 2,819; 801 case subjects). We further replicated 66 SNPs (P < 10⁻⁴) through genotyping in a Punjabi Sikh sample (n = 2,894; 1,711 case subjects). On combined meta-analysis in Sikh populations (n = 7,329; 3,354 case subjects), we identified a novel locus in association with T2D at 13q12 represented by a directly genotyped intronic SNP (rs9552911, P = 1.82 × 10⁻⁸) in the SGCG gene. Next, we undertook in silico replication (stage 2b) of the top 513 signals (P < 10⁻³) in 29,157 non-Sikh South Asians (10,971 case subjects) and de novo genotyping of up to 31 top signals (P < 10⁻⁴) in 10,817 South Asians (5,157 case subjects) (stage 3b). In combined South Asian meta-analysis, we observed six suggestive associations (P < 10⁻⁵ to < 10⁻⁷), including SNPs at HMG1L1/CTCFL, PLXNA4, SCAP, and chr5p11. Further evaluation of 31 top SNPs in 33,707 East Asians (16,746 case subjects) (stage 3c) and 47,117 Europeans (8,130 case subjects) (stage 3d), and joint meta-analysis of 128,127 individuals (44,358 case subjects) from 27 multiethnic studies, did not reveal any additional loci nor was there any evidence of replication for the new variant. Our findings provide new evidence on the presence of a population-specific signal in relation to T2D, which may provide additional insights into T2D pathogenesis.
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Affiliation(s)
- Richa Saxena
- Center for Human Genetic Research and Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Danish Saleheen
- Center for Non-Communicable Diseases, Karachi, Pakistan
- Department of Public Health and Primary Care, University of Cambridge, Cambridge, U.K
- Departments of Biostatistics and Epidemiology and Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Latonya F. Been
- Department of Pediatrics, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Martha L. Garavito
- Department of Pediatrics, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Timothy Braun
- Department of Pediatrics, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Andrew Bjonnes
- Center for Human Genetic Research and Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Robin Young
- Department of Public Health and Primary Care, University of Cambridge, Cambridge, U.K
| | - Weang Kee Ho
- Department of Public Health and Primary Care, University of Cambridge, Cambridge, U.K
| | - Asif Rasheed
- Center for Non-Communicable Diseases, Karachi, Pakistan
| | | | - Xueling Sim
- Center for Statistical Genetics and Department of Statistics, University of Michigan, Ann Arbor, Michigan
- Centre for Molecular Epidemiology, National University of Singapore, Singapore
| | - Neelam Hassanali
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, U.K
| | | | | | - Samuel Liju
- Madras Diabetes Research Foundation, Chennai, India
| | - Simon D. Rees
- College of Medical and Dental Sciences, University of Birmingham, Birmingham, U.K
- Diabetes Centre, Heart of England National Health Service Foundation Trust, Birmingham, U.K
| | - Daniel Peng-Keat Ng
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore
| | - Tien-Yin Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Department of Ophthalmology, National University of Singapore, Singapore
- Centre for Eye Research Australia, University of Melbourne, Melbourne, Australia
| | - Toshimasa Yamauchi
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Kazuo Hara
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
- Department of Integrated Molecular Science on Metabolic Diseases, 22nd Century Medical and Research Center, The University of Tokyo, Tokyo, Japan
| | - Yasushi Tanaka
- Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, Kanagawa, Japan
| | - Hiroshi Hirose
- Health Center, Keio University School of Medicine, Tokyo, Japan
| | - Mark I. McCarthy
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, U.K
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, U.K
- Oxford National Institute for Health Research Biomedical Research Centre, Churchill Hospital, Oxford, U.K
| | - Andrew P. Morris
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, U.K
| | | | | | | | - Abdul Basit
- Baqai Institute of Diabetology and Endocrinology, Karachi, Pakistan
| | - Anthony H. Barnett
- Diabetes Centre, Heart of England National Health Service Foundation Trust, Birmingham, U.K
| | - Prasad Katulanda
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, U.K
- Diabetes Research Unit, Department of Clinical Medicine, University of Colombo, Colombo, Sri Lanka
| | - David Matthews
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, U.K
| | - Viswanathan Mohan
- Madras Diabetes Research Foundation, Chennai, India
- Dr. Mohan's Diabetes Specialities Centre, Chennai, India
| | - Gurpreet S. Wander
- Hero Dayanand Medical College and Heart Institute, Ludhiana, Punjab, India
| | - Jai Rup Singh
- Central University of Punjab, Bathinda, Punjab, India
| | - Narinder K. Mehra
- All India Institute of Medical Sciences and Research, New Delhi, India
| | - Sarju Ralhan
- Hero Dayanand Medical College and Heart Institute, Ludhiana, Punjab, India
| | - M. Ilyas Kamboh
- Department of Human Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - John J. Mulvihill
- Department of Pediatrics, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Hiroshi Maegawa
- Department of Medicine, Shiga University of Medical Science, Shiga, Japan
| | - Kazuyuki Tobe
- First Department of Internal Medicine, University of Toyama, Toyama, Japan
| | - Shiro Maeda
- Laboratory for Endocrinology and Metabolism, RIKEN Center for Genomic Medicine, Kanagawa, Japan
| | - Yoon S. Cho
- Department of Biomedical Science, Hallym University, Chuncheon, Gangwon-do 200-702, Republic of Korea
| | - E. Shyong Tai
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Duke-NUS Graduate Medical School Singapore, Singapore
| | - M. Ann Kelly
- College of Medical and Dental Sciences, University of Birmingham, Birmingham, U.K
- Diabetes Centre, Heart of England National Health Service Foundation Trust, Birmingham, U.K
| | - John C. Chambers
- Ealing Hospital National Health Service Trust, Middlesex, U.K
- Imperial College Healthcare National Health Service Trust, London, U.K
- Epidemiology and Biostatistics, Imperial College London, London, U.K
| | - Jaspal S. Kooner
- Ealing Hospital National Health Service Trust, Middlesex, U.K
- Imperial College Healthcare National Health Service Trust, London, U.K
- National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, London, U.K
| | - Takashi Kadowaki
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | | | - Daniel J. Rader
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - John Danesh
- Department of Public Health and Primary Care, University of Cambridge, Cambridge, U.K
| | - Dharambir K. Sanghera
- Department of Pediatrics, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
- Corresponding author: Dharambir K. Sanghera,
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Tabassum R, Chauhan G, Dwivedi OP, Mahajan A, Jaiswal A, Kaur I, Bandesh K, Singh T, Mathai BJ, Pandey Y, Chidambaram M, Sharma A, Chavali S, Sengupta S, Ramakrishnan L, Venkatesh P, Aggarwal SK, Ghosh S, Prabhakaran D, Srinath RK, Saxena M, Banerjee M, Mathur S, Bhansali A, Shah VN, Madhu SV, Marwaha RK, Basu A, Scaria V, McCarthy MI, Venkatesan R, Mohan V, Tandon N, Bharadwaj D. Genome-wide association study for type 2 diabetes in Indians identifies a new susceptibility locus at 2q21. Diabetes 2013; 62:977-86. [PMID: 23209189 PMCID: PMC3581193 DOI: 10.2337/db12-0406] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Indians undergoing socioeconomic and lifestyle transitions will be maximally affected by epidemic of type 2 diabetes (T2D). We conducted a two-stage genome-wide association study of T2D in 12,535 Indians, a less explored but high-risk group. We identified a new type 2 diabetes-associated locus at 2q21, with the lead signal being rs6723108 (odds ratio 1.31; P = 3.32 × 10⁻⁹). Imputation analysis refined the signal to rs998451 (odds ratio 1.56; P = 6.3 × 10⁻¹²) within TMEM163 that encodes a probable vesicular transporter in nerve terminals. TMEM163 variants also showed association with decreased fasting plasma insulin and homeostatic model assessment of insulin resistance, indicating a plausible effect through impaired insulin secretion. The 2q21 region also harbors RAB3GAP1 and ACMSD; those are involved in neurologic disorders. Forty-nine of 56 previously reported signals showed consistency in direction with similar effect sizes in Indians and previous studies, and 25 of them were also associated (P < 0.05). Known loci and the newly identified 2q21 locus altogether explained 7.65% variance in the risk of T2D in Indians. Our study suggests that common susceptibility variants for T2D are largely the same across populations, but also reveals a population-specific locus and provides further insights into genetic architecture and etiology of T2D.
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Affiliation(s)
- Rubina Tabassum
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Ganesh Chauhan
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Om Prakash Dwivedi
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Anubha Mahajan
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Alok Jaiswal
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Ismeet Kaur
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Khushdeep Bandesh
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Tejbir Singh
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Benan John Mathai
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Yogesh Pandey
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Manickam Chidambaram
- Department of Molecular Genetics, Madras Diabetes Research Foundation-Indian Council of Medical Research Advanced Centre for Genomics of Diabetes, Chennai, India
| | - Amitabh Sharma
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Sreenivas Chavali
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Shantanu Sengupta
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Lakshmi Ramakrishnan
- Department of Endocrinology, All India Institute of Medical Sciences, New Delhi, India
| | - Pradeep Venkatesh
- Department of Endocrinology, All India Institute of Medical Sciences, New Delhi, India
| | - Sanjay K. Aggarwal
- Department of Endocrinology, All India Institute of Medical Sciences, New Delhi, India
| | - Saurabh Ghosh
- Human Genetics Unit, Indian Statistical Institute, Kolkata, India
| | | | | | - Madhukar Saxena
- Department of Zoology, University of Lucknow, Lucknow, India
| | | | - Sandeep Mathur
- Department of Endocrinology, SMS Medical College and Hospital, Jaipur, India
| | - Anil Bhansali
- Department of Endocrinology, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh, India
| | - Viral N. Shah
- Department of Endocrinology, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh, India
| | - Sri Venkata Madhu
- Division of Endocrinology, University College of Medical Sciences, Delhi, India
| | - Raman K. Marwaha
- Department of Endocrinology and Thyroid Research, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
| | - Analabha Basu
- National Institute of BioMedical Genomics, Kalyani, India
| | - Vinod Scaria
- GN Ramachandran Knowledge Center for Genome Informatics, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
| | - Mark I. McCarthy
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, United Kingdom
- Oxford National Institute for Health Research Biomedical Research Centre, Churchill Hospital, Oxford, United Kingdom
| | | | | | - Radha Venkatesan
- Department of Molecular Genetics, Madras Diabetes Research Foundation-Indian Council of Medical Research Advanced Centre for Genomics of Diabetes, Chennai, India
| | - Viswanathan Mohan
- Department of Molecular Genetics, Madras Diabetes Research Foundation-Indian Council of Medical Research Advanced Centre for Genomics of Diabetes, Chennai, India
| | - Nikhil Tandon
- Department of Endocrinology, All India Institute of Medical Sciences, New Delhi, India
- Corresponding authors: Dwaipayan Bharadwaj, , and Nikhil Tandon,
| | - Dwaipayan Bharadwaj
- Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi, India
- Corresponding authors: Dwaipayan Bharadwaj, , and Nikhil Tandon,
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Rajapandiyan C, Chidambaram M. Controller Design for MIMO Processes Based on Simple Decoupled Equivalent Transfer Functions and Simplified Decoupler. Ind Eng Chem Res 2012. [DOI: 10.1021/ie301448c] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Rajapandiyan C, Chidambaram M. Closed-Loop Identification of Second-Order Plus Time Delay (SOPTD) Model of Multivariable Systems by Optimization Method. Ind Eng Chem Res 2012. [DOI: 10.1021/ie203003p] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- C. Rajapandiyan
- Department of Chemical Engineering, Indian Institute of Technology, Madras, Chennai 600036, India
| | - M. Chidambaram
- Department of Chemical Engineering, Indian Institute of Technology, Madras, Chennai 600036, India
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Vijay Kumar V, Rao VSR, Chidambaram M. Centralized PI controllers for interacting multivariable processes by synthesis method. ISA Trans 2012; 51:400-409. [PMID: 22405751 DOI: 10.1016/j.isatra.2012.02.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 01/16/2012] [Accepted: 02/10/2012] [Indexed: 05/31/2023]
Abstract
In this article, two methods of designing a centralized control system for multi-input, multi-output (MIMO) processes are presented. Centralized proportional-integral (PI) controllers are designed based on a direct synthesis method. The inverse of the process transfer function matrix in the direct synthesis method is approximated based on the relative gain array concept. The method is further improved by using a relative normalized gain array, and an equivalent transfer function for each element in the process transfer function matrix is derived for the closed-loop control system. The transpose of the effective transfer function is used to approximate the inverse of the process transfer function matrix. The simulation studies demonstrate the effectiveness of this method. The proposed centralized controllers reduce the interactions better than recently reported decentralized controllers do. A centralized controller designed based on a relative normalized gain array (RNGA) gives a better performance than a centralized controller designed based on a relative gain array (RGA).
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Affiliation(s)
- V Vijay Kumar
- Department of Chemical Engineering, Indian Institute of Technology, Madras, Chennai-600036, India
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Affiliation(s)
- C. Rajapandiyan
- Department of Chemical Engineering, Indian Institute of Technology, Madras, Chennai-600036, India
| | - M. Chidambaram
- Department of Chemical Engineering, Indian Institute of Technology, Madras, Chennai-600036, India
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Chidambaram M, Radha V, Mohan V. Replication of recently described type 2 diabetes gene variants in a South Indian population. Metabolism 2010; 59:1760-6. [PMID: 20580033 DOI: 10.1016/j.metabol.2010.04.024] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Revised: 04/28/2010] [Accepted: 04/28/2010] [Indexed: 12/11/2022]
Abstract
Recent genomewide association studies have identified several new gene variants associated with type 2 diabetes mellitus (T2D) mostly in European populations. These need to be replicated in other populations. We studied 926 unrelated T2D and 812 normal glucose-tolerant subjects randomly selected from the Chennai Urban Rural Epidemiology Study in Southern India. A total of 45 single nucleotide polymorphisms (SNPs) from 15 genes and 13 unannotated loci identified from recent genomewide association T2D studies were genotyped. Only 6 of 45 SNPs studied were replicated in this South Indian population. Three SNPs-rs7756992 (P = .007), rs7754840 (P = .015), and rs6931514 (P = .029)-of the CDKAL1, rs7020996 (P = .003) of the CDKN2A/B gene, rs7923837 (P = .038) of the HHEX gene, and rs12056034 (P = .033) of the BAZ1B gene were associated with T2D in our population. Large-scale studies are needed in our population to validate our findings.
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Affiliation(s)
- Manickam Chidambaram
- Department of Molecular Genetics, Madras Diabetes Research Foundation-ICMR Advanced Centre for Genomics of Diabetes, Chennai 603103, India
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Uma S, Chidambaram M, Rao AS. Set point weighted modified Smith predictor with PID filter controllers for non-minimum-phase (NMP) integrating processes. Chem Eng Res Des 2010. [DOI: 10.1016/j.cherd.2009.09.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Rao AS, Seethaladevi S, Uma S, Chidambaram M. Enhancing the performance of parallel cascade control using Smith predictor. ISA Trans 2009; 48:220-227. [PMID: 19054509 DOI: 10.1016/j.isatra.2008.10.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Revised: 10/24/2008] [Accepted: 10/31/2008] [Indexed: 05/27/2023]
Abstract
Parallel cascade controllers are used in chemical processing industries to improve the dynamic performance of a control system in the presence of disturbances. In the present work, a delay compensator has been incorporated in the primary loop of the parallel cascade control system. The secondary controller is designed using the internal model control (IMC) method. The primary controller is designed based on a direct synthesis method for the delay-free system. Design of controllers for slow (when the secondary loop dynamics is slow i.e. process contains poles sufficiently slower than the desired closed loop response) as well as fast dynamics (when the inner loop dynamics is fast i.e. process contains poles sufficiently faster than the desired closed loop response) of the secondary process is considered. The method provides robust control performances. Significant improvement in the closed loop performances are obtained with the delay compensator over that of a conventional parallel cascade control system. Several case studies are considered to show the advantage of the proposed method when compared to other recently reported methods.
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Affiliation(s)
- A Seshagiri Rao
- Department of Chemical Engineering, National Institute of Technology, Tiruchirappalli-620 015, India.
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Affiliation(s)
- S. Uma
- Department of Chemical Engineering, National Institute of Technology, Tiruchirappalli 620 015, India
| | - M. Chidambaram
- Department of Chemical Engineering, National Institute of Technology, Tiruchirappalli 620 015, India
| | - A. Seshagiri Rao
- Department of Chemical Engineering, National Institute of Technology, Tiruchirappalli 620 015, India
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