27 results on '"Sithambaram S"'
Search Results
2. G344(P) Ketogenic diet in childhood epilepsy – recent advances and future challenges
- Author
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Sithambaram, S
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- 2014
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3. Toxicity Effects of Oral Administration of Clinacanthus nutans Ethanolic Leaf Extract on Blood, Liver and Kidneys of Mice
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Aliyu, A., primary, Shaari, M. R., additional, Ahmad Sayuti, Nurul Syahirah, additional, Reduan, M. F. H., additional, Nadia Asyura, Sajjarattul Nurul, additional, Sithambaram, S., additional, Noordin, M. M., additional, Shaari, Khozirah, additional, and Hamzah, Hazilawati, additional
- Published
- 2021
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4. Tandem catalysis: Direct catalytic synthesis of imines from alcohols using manganese octahedral molecular sieves
- Author
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SITHAMBARAM, S, primary, KUMAR, R, additional, SON, Y, additional, and SUIB, S, additional
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- 2008
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5. Hydrothermal Synthesis of Structure- and Shape-Controlled Manganese Oxide Octahedral Molecular Sieve Nanomaterials
- Author
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Li, W.-N., primary, Yuan, J., additional, Shen, X.-F., additional, Gomez-Mower, S., additional, Xu, L.-P., additional, Sithambaram, S., additional, Aindow, M., additional, and Suib, S. L., additional
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- 2006
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6. Microwave frequency effects on synthesis of cryptomelane-type manganese oxide and catalytic activity of cryptomelane precursor
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MALINGER, K, primary, DING, Y, additional, SITHAMBARAM, S, additional, ESPINAL, L, additional, GOMEZ, S, additional, and SUIB, S, additional
- Published
- 2006
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7. Synthesis and Catalytic Activity of Cryptomelane-Type Manganese Dioxide Nanomaterials Produced by a Novel Solvent-Free Method
- Author
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Ding, Y.-s., Shen, X.-f., Sithambaram, S., Gomez, S., Kumar, R., Crisostomo, V. M. B., Suib, S. L., and Aindow, M.
- Abstract
Cryptomelane-type K-OMS-2 nanomaterials with high surface area (156 m2/g) have been synthesized via a low-temperature solvent-free method in a very short time (1 h). Field emission scanning electron microscopy and high-resolution transmission electron microscopy images reveal that these materials have nanorod morphologies with average diameters of about 10 nm and lengths of about 50 nm. These are different from the long fiberous morphologies of OMS-2 materials made by conventional reflux or hydrothermal methods. X-ray diffraction and Brunauer−Emmett−Teller studies indicate that these materials have small crystallite sizes (~9.8 nm) and that they are mesoporous with a uniform pore size distribution centered at 12 nm. These K-OMS-2 materials show improved catalytic activity for the oxidation of alcohols compared with the conventional K-OMS-2 materials, which may be due to their higher surface areas and novel surface properties. This fast, inexpensive, and environmentally friendly solvent-free method has the potential of being used in scaled-up syntheses of K-OMS-2 and other transition-metal-ion-substituted manganese oxide nanomaterials.
- Published
- 2005
8. Acute and sub-acute dermal toxicity studies of Morinda citrifolia L. fruit extract in sprague dawley rats
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Zahi, A. K., Hamzah, H., Hutheyfa, S., Shaari, M. R., Sithambaram, S., and Hemn Othman
9. Low levels of microvessel density and immunohistochemical expression of vascular endothelial growth factor in carcinogen-induced ductal mammary gland carcinoma of rats supplemented with garlic
- Author
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Hussein, H. A., Hamzah, H., Shari, M. R., Sabri, J., Mustapha, N. M., and Sithambaram, S.
10. PRKACA-related, atrial defects-polydactyly-multiple congenital malformation syndrome in an Indian patient.
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Sithambaram S, Jacob P, Neethukrishna K, Bhavani GS, Dalal A, Shah H, and Girisha KM
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- Humans, Female, Heart Septal Defects, Atrial genetics, Heart Septal Defects, Atrial diagnostic imaging, Heart Septal Defects, Atrial diagnosis, Heart Septal Defects, Atrial pathology, Male, Phenotype, Mutation genetics, Heart Defects, Congenital genetics, Heart Defects, Congenital pathology, Heart Defects, Congenital diagnosis, Heart Defects, Congenital diagnostic imaging, India, Polydactyly genetics, Polydactyly pathology, Polydactyly diagnosis, Abnormalities, Multiple genetics, Abnormalities, Multiple pathology, Abnormalities, Multiple diagnosis
- Abstract
PRKACA-related, atrial defects-polydactyly-multiple congenital malformation syndrome is a recently described skeletal ciliopathy, which is caused by disease-causing variants in PRKACA. The primary phenotypic description includes atrial septal defects, and limb anomalies including polydactyly and short limbs. To date, only four molecularly proven patients have been reported in the literature with a recurrent variant, c.409G>A p.Gly137Arg in PRKACA. In this study, we report the fifth affected individual with the same variant and review the clinical features and radiographic findings of this rare syndrome., (© 2024 Wiley Periodicals LLC.)
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- 2024
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11. Patient Tailored Surgery in Saethre-Chotzen Syndrome: Analysis of Reoperation for Intracranial Hypertension.
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Kurzbuch AR, Cooper B, Duncan C, Ellenbogen J, Richardson D, Sinha A, Weber A, Sithambaram S, Hennedige A, and Parks C
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- Male, Female, Humans, Infant, Reoperation, Skull surgery, Acrocephalosyndactylia complications, Craniosynostoses surgery, Craniosynostoses complications, Intracranial Hypertension etiology
- Abstract
Saethre-Chotzen syndrome (SCS) is a syndromic craniosynostosis with pathogenic variants in the TWIST1 gene showing a broad phenotypic spectrum. Controversies exist in the literature regarding surgical management with single one-stage versus patient-tailored surgery and the related reoperation rate for intracranial hypertension of up to 42%. At our center, SCS patients are offered patient-tailored surgery with single-stage fronto-orbital advancement and remodeling or fronto-orbital advancement and remodeling and posterior distraction in an individually determined order. The authors' database identified 35 confirmed SCS patients between 1999 and 2022. Involved sutures in craniosynostosis were left unicoronal (22.9%), bicoronal (22.9%), sagittal (8.6%), bicoronal and sagittal (5.7%), right unicoronal (2.9%), bicoronal and metopic (2.9%), bicoronal, sagittal and metopic (2.9%), and bilateral lambdoid (2.9%). There was pansynostosis in 8.6% and no craniosynostosis in 14.3% of the patients. Twenty-six patients, 10 females, and 16 males were operated on. Mean age at the first surgery was 1.70 years, and 3.86 years at the second surgery. Eleven of 26 patients had invasive intracranial pressure monitoring. Three patients presented with papilledema before the first surgery and 4 afterward. Four of the 26 operated patients were operated initially elsewhere. The other 22 patients were initially referred to our unit and underwent patient-tailored surgery. Nine of these patients (41%) had a second surgery, and 3 (14%) of them were because of raised intracranial pressure. Seven (27%) of all operated patients had a complication. Median follow-up was 13.98 years (range, 1.85-18.08). Patient-tailored surgery in a specialized center and long-term follow-up allow for a low reoperation rate for intracranial hypertension., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)
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- 2023
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12. Differential involvement of germline pathogenic variants in breast cancer genes between DCIS and low-grade invasive cancers.
- Author
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Evans DG, Sithambaram S, van Veen EM, Burghel GJ, Schlecht H, Harkness EF, Byers H, Ellingford JM, Gandhi A, Howell SJ, Howell A, Forde C, Lalloo F, Newman WG, Smith MJ, and Woodward ER
- Subjects
- Female, Humans, BRCA1 Protein genetics, BRCA2 Protein genetics, Germ-Line Mutation genetics, Genes, BRCA2, Germ Cells pathology, Carcinoma, Intraductal, Noninfiltrating diagnosis, Carcinoma, Intraductal, Noninfiltrating genetics, Carcinoma, Intraductal, Noninfiltrating pathology, Breast Neoplasms diagnosis, Breast Neoplasms genetics, Breast Neoplasms epidemiology
- Abstract
Purpose: To investigate frequency of germline pathogenic variants (PVs) in women with ductal carcinoma in situ (DCIS) and grade 1 invasive breast cancer (G1BC)., Methods: We undertook BRCA1/2 analysis in 311 women with DCIS and 392 with G1BC and extended panel testing (non- BRCA1 / 2 ) in 176/311 with DCIS and 156/392 with G1BC. We investigated PV detection by age at diagnosis, Manchester Score (MS), DCIS grade and receptor status., Results: 30/311 (9.6%) with DCIS and 16/392 with G1BC (4.1%) had a BRCA1 / 2 PV (p=0.003), and 24/176-(13.6%) and 7/156-(4.5%), respectively, a non- BRCA1 / 2 PV (p=0.004). Increasing MS was associated with increased likelihood of BRCA1/2 PV in both DCIS and G1BC, although the 10% threshold was not predictive for G1GB. 13/32 (40.6%) DCIS and 0/17 with G1BC <40 years had a non-BRCA1/2 PV (p<0.001). 0/16 DCIS G1 had a PV. For G2 and G3 DCIS, PV rates were 10/98 ( BRCA1 / 2 ) and 9/90 (non- BRCA1 / 2 ), and 8/47 ( BRCA1 / 2 ) and 8/45 (non- BRCA1 / 2 ), respectively. 6/9 BRCA1 and 3/26 BRCA2 -associated DCIS were oestrogen receptor negative-(p=0.003). G1BC population testing showed no increased PV rate (OR=1.16, 95% CI 0.28 to 4.80)., Conclusion: DCIS is more likely to be associated with both BRCA1/2 and non- BRCA1 / 2 PVs than G1BC. Extended panel testing ought to be offered in young-onset DCIS where PV detection rates are highest., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2023
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13. The development of a novel, multilingual IBD knowledge questionnaire for Asian patients with inflammatory bowel disease.
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Razima Wan Ibrahim N, Danaee M, Khoo XH, Sithambaram S, Shahrani S, Hwong-Ruey Leow A, Chang JV, Francis Mayberry J, and Normiha Hilmi I
- Subjects
- Humans, Prospective Studies, Reproducibility of Results, India, Surveys and Questionnaires, Psychometrics, Health Knowledge, Attitudes, Practice, Inflammatory Bowel Diseases diagnosis
- Abstract
Background: Inflammatory bowel disease is an uncommon disease in developing nations whereby patient's knowledge on the disease may be limited. The CCKNOW questionnaire, a widely known questionnaire to assess patient's knowledge on the disease, may be too complex to comprehend for patients in developing countries. The aim of this study is to develop a new tool known as AIBDKQ questionnaire to evaluate the local inflammatory bowel disease patient's knowledge., Methods: This was a prospective study carried out in four phases. In phase 1, three gastroenterologists with expertise in IBD generated a total of 21 questions related to the general knowledge of the disease in the English language. Phase 2 involved content and face validity whereby the questions were further validated by other gastroenterologists. In phase 3, the validated questions were translated into three languages namely Malay, Mandarin and Tamil which are commonly used in Malaysia. In phase 4 (statistical validity), administration of the questionnaires to patients and hospital staff were conducted to assess the construct validity, discriminative ability, predictive validity and reliability of the questionnaires., Results: A total of 21 questions were generated initially. Further evaluation indicated that 20 items had adequate kappa and content validity index for relevance (CVI: 0.714 to 1, Kapp: 0.645 to 1) and clarity (CVI: 0.714 to 1, Kapp: 0.645 to 1). The questionnaires in four languages were administered to 213 patients to assess the construct validity. Six items were removed (three for low communality, one for small loading factors, two for cross loading), resulting in 16 final questions. Assessment with 34 hospital staff involving nurses, doctors and clerks showed significant differences in knowledge between the groups (F = 14.007, p < 0.001) and were able to discriminate doctors from nurses and clerks. Another group of 18 hospital staff administered with AIBDKQ and CCKNOW questionnaires showed a Pearson's correlation coefficient of 0.8 indicating strong correlation and concurrent predictive validity between the two questionnaires. Final assessment with 38 patients for reliability assessment revealed high intraclass correlation of the questionnaire among the four languages., Conclusions: The AIBDKQ has an excellent discriminant ability and internal consistency with a strong correlation when compared to the standard CCKNOW questionnaire., (© 2023. The Author(s).)
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- 2023
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14. Author Correction: Deficiency of TET3 leads to a genome-wide DNA hypermethylation episignature in human whole blood.
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Levy MA, Beck DB, Metcalfe K, Douzgou S, Sithambaram S, Cottrell T, Ansar M, Kerkhof J, Mignot C, Nougues MC, Keren B, Moore HW, Oegema R, Giltay JC, Simon M, van Jaarsveld RH, Bos J, van Haelst M, Motazacker MM, Boon EMJ, Santen GWE, Ruivenkamp CAL, Alders M, Luperchio TR, Boukas L, Ramsey K, Narayanan V, Schaefer GB, Bonasio R, Doheny KF, Stevenson RE, Banka S, Sadikovic B, and Fahrner JA
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- 2021
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15. Deficiency of TET3 leads to a genome-wide DNA hypermethylation episignature in human whole blood.
- Author
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Levy MA, Beck DB, Metcalfe K, Douzgou S, Sithambaram S, Cottrell T, Ansar M, Kerkhof J, Mignot C, Nougues MC, Keren B, Moore HW, Oegema R, Giltay JC, Simon M, van Jaarsveld RH, Bos J, van Haelst M, Motazacker MM, Boon EMJ, Santen GWE, Ruivenkamp CAL, Alders M, Luperchio TR, Boukas L, Ramsey K, Narayanan V, Schaefer GB, Bonasio R, Doheny KF, Stevenson RE, Banka S, Sadikovic B, and Fahrner JA
- Abstract
TET3 encodes an essential dioxygenase involved in epigenetic regulation through DNA demethylation. TET3 deficiency, or Beck-Fahrner syndrome (BEFAHRS; MIM: 618798), is a recently described neurodevelopmental disorder of the DNA demethylation machinery with a nonspecific phenotype resembling other chromatin-modifying disorders, but inconsistent variant types and inheritance patterns pose diagnostic challenges. Given TET3's direct role in regulating 5-methylcytosine and recent identification of syndrome-specific DNA methylation profiles, we analyzed genome-wide DNA methylation in whole blood of TET3-deficient individuals and identified an episignature that distinguishes affected and unaffected individuals and those with mono-allelic and bi-allelic pathogenic variants. Validation and testing of the episignature correctly categorized known TET3 variants and determined pathogenicity of variants of uncertain significance. Clinical utility was demonstrated when the episignature alone identified an affected individual from over 1000 undiagnosed cases and was confirmed upon distinguishing TET3-deficient individuals from those with 46 other disorders. The TET3-deficient signature - and the signature resulting from activating mutations in DNMT1 which normally opposes TET3 - are characterized by hypermethylation, which for BEFAHRS involves CpG sites that may be biologically relevant. This work expands the role of epi-phenotyping in molecular diagnosis and reveals genome-wide DNA methylation profiling as a quantitative, functional readout for characterization of this new biochemical category of disease., (© 2021. The Author(s).)
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- 2021
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16. Moringa oleifera hydorethanolic leaf extract induced acute and sub-acute hepato-nephrotoxicity in female ICR-mice.
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Aliyu A, Shaari MR, Ahmad Sayuti NS, Reduan FH, Sithambaram S, Mohamed Mustapha N, Shaari K, and Hamzah HB
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- Animals, Female, Mice, Mice, Inbred ICR, Necrosis drug therapy, Plant Extracts toxicity, Quercetin, Moringa oleifera chemistry
- Abstract
Moringa oleifera (M. oleifera) Lam belongs to the family Moringaceae. It is an important multipurpose tree that is largely distributed globally and has been used almost in every aspect of traditional medicine for the treatment of various illnesses including cancers, diabetes mellitus, asthma, arthritis, etc. This study investigated the effects of oral acute and sub-acute administration of M. oleifera hydroethanolic leaf extract (MOHE) in ICR-mice. Its major phenolic compounds were also determined. Ten (10) female, 8-week old mice were grouped into control and treatment groups for acute toxicity study. A dose of 2000 mg/kg MOHE was given once to the treatment group via oral gavage. However, for the sub-acute toxicity study, 25 mice were grouped into groups A (control), B (125 mg/kg), C (250 mg/kg), D (500 mg/kg) and E (1000 mg/kg). MOHE was given via oral gavage to groups B, C, D and E daily for 28 days. Group A received only distilled water. The mice were sacrificed at the end of the experiments and samples were collected for evaluation. The results of the chemical profiling of MOHE revealed the presence of glucomoringin, niaziminine, quercetin and kaempferol as the major compounds. The treated mice in the acute toxicity study were slightly anaemic and showed evidence of stress leukogram. Moreover, a slight increase in creatinine, significant increases in AST and CK, hepatic degeneration and necrosis, none-obstructive sinusoidal dilatation, renal tubular necrosis, interstitial nephritis and renal interstitial oedema were observed. It is concluded that the LD
50 of MOHE is higher than 2000 mg/kg. However, oral administration of MOHE causes acute mild anaemia and moderate hepato-nephrotoxicity in ICR-mice. Its major phenolic compounds are glucomoringin, niaziminine, quercetin and kaempferol.- Published
- 2021
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17. Subacute Oral Administration of Clinacanthus nutans Ethanolic Leaf Extract Induced Liver and Kidney Toxicities in ICR Mice.
- Author
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Aliyu A, Shaari MR, Ahmad Sayuti NS, Reduan MFH, Sithambaram S, Noordin MM, Shaari K, and Hamzah H
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- Administration, Oral, Animals, Chemical and Drug Induced Liver Injury etiology, Female, Kidney drug effects, Lethal Dose 50, Male, Mice, Mice, Inbred ICR, Acanthaceae chemistry, Chemical and Drug Induced Liver Injury pathology, Kidney pathology, Plant Extracts administration & dosage, Plant Extracts toxicity, Plant Leaves chemistry, Toxicity Tests, Acute methods
- Abstract
This study investigated the leaves of Clinacanthus nutans for its bioactive compounds and acute and subacute toxicity effects of C. nutans ethanolic leaf extract (CELE) on blood, liver and kidneys of ICR mice. A total of 10 8-week-old female mice were divided into groups A (control) and B (2000 mg/kg) for the acute toxicity study. A single dose of 2000 mg/kg was administered to group B through oral gavage and mice were monitored for 14 days. In the subacute toxicity study, mice were divided into five groups: A (control), B (125 mg/kg), C (250 mg/kg), D (500 mg/kg) and E (1000 mg/kg). The extract was administered daily for 28 days via oral gavage. The mice were sacrificed, and samples were collected for analyses. Myricetin, orientin, isoorientin, vitexin, isovitexin, isookanin, apigenin and ferulic acid were identified in the extract. Twenty-eight days of continuous oral administration revealed significant increases ( p < 0.05) in creatinine, ALT and moderate hepatic and renal necrosis in groups D and E. The study concluded that the lethal dose (LD
50 ) of CELE in mice is greater than 2000 mg/kg and that repeated oral administrations of CELE for 28 days induced hepatic and renal toxicities at 1000 mg/kg in female ICR mice.- Published
- 2020
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18. Acute and subacute dermal toxicity of ethanolic extract of Melastoma malabathricum leaves in Sprague-Dawley rats.
- Author
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Reduan FH, Shaari RM, Sayuti NSA, Mustapha NM, Abu Bakar MZ, Sithambaram S, and Hamzah H
- Abstract
Melastoma malabathricum is a well-known herb in Malaysia where it being used in various ways for treatment of different diseases and ailments including skin problems. The study aims to investigate acute and subacute dermal toxicity of ethanolic extract of M. malabathricum leaves following to a single or repeated doses exposure. A total of 30 female Sprague-Dawley rats were grouped into 5 groups (n = 6 per group) for both acute and subacute toxicity study. The duration for each study was determined at 14 days for acute toxicity and 28 days for subacute toxicity. The rats were topically applied with the plant extract at three different doses; 2.5%, 5.0% and 10.0% on the shaved area of dorsal skin. For acute toxicity study, rats in all three groups received single application of the extract on the first day of the experimental period, while rats in subacute toxicity study were topically applied with the extract once daily for 28 days. Throughout the respective 14-day and 28-day study periods, all rats were monitored for any changes in their physical appearance and behavioural patterns that might develop due to toxic effects of the plant. There were no mortality or abnormal physical appearance, and physiological and behavioural changes observed in all rats in both studies. Body weights, kidney and liver weights, and both haematology and serum biochemistry results showed no significant ( p > 0.05) differences between all groups in both studies. All of the findings were supported by normal macroscopic and microscopic architectures of liver, kidneys and skin of all rats applied topically with the extract. This study suggests that topical application of M. malabathricum leaf ethanolic extract at 2.5%, 5% and 10% does not induce acute and subacute adverse effects on the skin or systemic toxic reactions in rats., Competing Interests: Conflict of interestThe authors have no conflict of interest to disclose., (© Korean Society of Toxicology 2020.)
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- 2020
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19. N -Ethyl- n -Nitrosourea Induced Leukaemia in a Mouse Model through Upregulation of Vascular Endothelial Growth Factor and Evading Apoptosis.
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Aliyu A, Shaari MR, Ahmad Sayuti NS, Reduan MFH, Sithambaram S, Noordin MM, Shaari K, and Hamzah H
- Abstract
Chemical carcinogens are commonly used to investigate the biology and prognoses of various cancers. This study investigated the mechanism of leukaemogenic effects of n -ethyl- n -nitrosourea (ENU) in a mouse model. A total of 14 3-week-old male Institute of Cancer Research (ICR)-mice were used for the study. The mice were divided into groups A and B with seven mice each. Group A served as the control while group B received intraperitoneal (IP) injections of 80 mg/kg ENU twice with a one-week interval and were monitored monthly for 3 months for the development of leukaemia via blood smear examination. The mice were sacrificed humanely using a CO
2 chamber. Blood, spleen, lymph nodes, liver, kidney and lung samples were collected for blood smear examination and histopathological evaluation. The expression of angiogenic protein (VEGF), and pro and anti-apoptotic proteins (BCL2 and BAX), was detected and quantified using Western blot technique. Leukaemia was confirmed by the presence of numerous blast cells in the peripheral blood smear in group B. Similarly, the VEGF and BCL2 proteins were significantly ( p < 0.05) upregulated in group B compared to A. It is concluded that IP administration of 80 mg/kg ENU induced leukaemia in ICR-mice 12 weeks post administration through upregulation of angiogenic and anti-apoptotic proteins: VEGF and BCL2.- Published
- 2020
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20. Delineation of a Human Mendelian Disorder of the DNA Demethylation Machinery: TET3 Deficiency.
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Beck DB, Petracovici A, He C, Moore HW, Louie RJ, Ansar M, Douzgou S, Sithambaram S, Cottrell T, Santos-Cortez RLP, Prijoles EJ, Bend R, Keren B, Mignot C, Nougues MC, Õunap K, Reimand T, Pajusalu S, Zahid M, Saqib MAN, Buratti J, Seaby EG, McWalter K, Telegrafi A, Baldridge D, Shinawi M, Leal SM, Schaefer GB, Stevenson RE, Banka S, Bonasio R, and Fahrner JA
- Subjects
- Adult, Amino Acid Sequence, Autistic Disorder genetics, Autistic Disorder pathology, Child, Child, Preschool, Dioxygenases chemistry, Dioxygenases genetics, Embryonic Development, Female, Gene Expression Regulation, Developmental, Growth Disorders genetics, Growth Disorders pathology, Humans, Infant, Male, Middle Aged, Movement Disorders genetics, Movement Disorders pathology, Pedigree, Protein Conformation, Sequence Homology, Young Adult, DNA Demethylation, Developmental Disabilities genetics, Developmental Disabilities pathology, Dioxygenases deficiency
- Abstract
Germline pathogenic variants in chromatin-modifying enzymes are a common cause of pediatric developmental disorders. These enzymes catalyze reactions that regulate epigenetic inheritance via histone post-translational modifications and DNA methylation. Cytosine methylation (5-methylcytosine [5mC]) of DNA is the quintessential epigenetic mark, yet no human Mendelian disorder of DNA demethylation has yet been delineated. Here, we describe in detail a Mendelian disorder caused by the disruption of DNA demethylation. TET3 is a methylcytosine dioxygenase that initiates DNA demethylation during early zygote formation, embryogenesis, and neuronal differentiation and is intolerant to haploinsufficiency in mice and humans. We identify and characterize 11 cases of human TET3 deficiency in eight families with the common phenotypic features of intellectual disability and/or global developmental delay; hypotonia; autistic traits; movement disorders; growth abnormalities; and facial dysmorphism. Mono-allelic frameshift and nonsense variants in TET3 occur throughout the coding region. Mono-allelic and bi-allelic missense variants localize to conserved residues; all but one such variant occur within the catalytic domain, and most display hypomorphic function in an assay of catalytic activity. TET3 deficiency and other Mendelian disorders of the epigenetic machinery show substantial phenotypic overlap, including features of intellectual disability and abnormal growth, underscoring shared disease mechanisms., (Copyright © 2019 American Society of Human Genetics. All rights reserved.)
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- 2020
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21. Dilemma of diagnosing sulphonylurea overdose in children: deliberations and considerations before reaching a diagnosis.
- Author
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Gopal-Kothandapani JS, Wright KP, Sithambaram S, and Natarajan A
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- Adolescent, Blood Glucose analysis, Diagnosis, Differential, Drug Overdose urine, Emergency Service, Hospital, Female, Gliclazide administration & dosage, Gliclazide urine, Glucose administration & dosage, Glucose therapeutic use, Humans, Hydrocortisone administration & dosage, Hydrocortisone therapeutic use, Hypoglycemia complications, Hypoglycemia drug therapy, Hypoglycemic Agents administration & dosage, Infusions, Intravenous, Insulin blood, Seizures complications, Suicide, Attempted psychology, Treatment Outcome, Gliclazide poisoning, Hypoglycemia chemically induced, Hypoglycemic Agents poisoning, Seizures chemically induced, Seizures diagnosis
- Abstract
A 15-year-old non-diabetic Caucasian girl presented with sudden onset of seizures, unrecordable blood glucose readings and acute renal failure. She denied any medication ingestion and no other precipitating factors were encountered for this acute presentation. She was treated with intravenous glucose infusion and hydrocortisone injection. Investigations showed a non-ketotic hypoglycaemia with high C-peptide and insulin levels. It took several days and multiple investigations to establish the exact cause of her persistent hypoglycaemia before it was concluded to be secondary to gliclazide overdose in a suicide attempt by the young girl. She made a complete recovery in a week with no apparent lasting neurological or renal impairment., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)
- Published
- 2017
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22. A 7-year-old boy with dysphagia and proximal muscle weakness.
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Sithambaram S, Tripathi N, Gopal-Kothandapani JS, and Mordekar S
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- 2017
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23. Immunotoxin therapy for hematologic malignancies: where are we heading?
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Madhumathi J, Devilakshmi S, Sridevi S, and Verma RS
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- Animals, Humans, Ligands, Hematologic Neoplasms drug therapy, Immunotoxins therapeutic use
- Abstract
The identification of numerous unique targets in recent years has led to the development of various immunotoxins (ITs) for treating hematological malignancies. Some of these ITs have advanced to clinical trials and have resulted in a high response rate against leukemia. Newer targets with improve specificity are also being identified for targeting several leukemias. Currently, several modified versions of ITs with increased efficacy are being constructed and evaluated for cytotoxicity in vitro as well as in vivo. Here, we summarize recent advances in preclinical and clinical studies of recombinant ITs targeting diverse surface receptors., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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24. Inherited duplication of the short arm of chromosome 18p11.32-p11.31 associated with developmental delay/intellectual disability.
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Balasubramanian M, Sithambaram S, and Smith K
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- Adult, Autistic Disorder genetics, Child, Comparative Genomic Hybridization, Female, Gene Duplication, Genetic Association Studies, Humans, In Situ Hybridization, Fluorescence, Male, Pedigree, Chromosome Duplication genetics, Chromosomes, Human, Pair 18 genetics, Developmental Disabilities genetics, Intellectual Disability genetics
- Abstract
Duplications of 18p have been reported in the literature associated with a range of different abnormalities and also in patients with normal phenotypes. The majority of these reports are based solely on G-banded cytogenetic evaluation. The use of arrayCGH characterization has improved the ability to define regions of imbalance and is helping to identify potential underlying triplosufficiency of any duplicated genes. We report on a family where the father and his two daughters all have a duplication 18p11.32-p11.31 characterized by microarray. They present with variable levels of intellectual disability/developmental delay and behavioural difficulties without any physical anomalies. This family contributes toward the growing knowledge of pure duplications of 18p and provides information on interpretation of novel array findings in the context of family history. It also reiterates the importance of elucidating a detailed learning and developmental phenotype and family pedigree in aiding interpretation of genetic testing results.
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- 2016
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25. The Diagnostic Accuracy of the M2 Pyruvate Kinase Quick Stool Test--A Rapid Office Based Assay Test for the Detection of Colorectal Cancer.
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Sithambaram S, Hilmi I, and Goh KL
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- Aged, Colonoscopy, Colorectal Neoplasms diagnosis, Female, Humans, Male, Middle Aged, Neoplasm Staging, Point-of-Care Systems, Predictive Value of Tests, Sensitivity and Specificity, Biomarkers, Tumor metabolism, Colorectal Neoplasms enzymology, Feces enzymology, Pyruvate Kinase metabolism
- Abstract
Background: M2 pyruvate kinase (M2PK) is an oncoprotein secreted by colorectal cancers in stools. This the first report on the accuracy of a rapid stool test in the detection of colorectal cancer (CRC)., Objective: To determine the sensitivity, specificity and positive and negative predictive value of a rapid, point of care stool test M2 PK- the M2PK Quick., Methods: Consecutive cases of endoscopically diagnosed and histological proven CRC were recruited. Stools were collected by patients and tested with the immunochromatographic M2PK Quick Test (Schebo Biotech AC, Giessen, Germany). Controls were consecutively chosen from patients without any significant colorectal or gastrointestinal disease undergoing colonoscopy. CRC was staged according to the AJCC staging manual (7th Edition) and location of tumor defined as proximal or distal., Results: The sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy were: 93%, 97.5%, 94.9%, 96.5% and 96.0% respectively. The positive predictive value for proximal tumors was significantly lower compared to distal tumors. No differences were seen between the different stages of the tumor., Conclusions: The M2-PK Quick, rapid, point-of-care test is a highly accurate test in the detection of CRC. It is easy and convenient to perform and a useful diagnostic test for the detection of CRC in a clinical practice setting.
- Published
- 2015
- Full Text
- View/download PDF
26. Mandarin version of the Leeds Dyspepsia Questionnaire: A valid instrument for assessing symptoms in Asians.
- Author
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Leow HR, Ching SM, Sujarita R, Yap CF, Chia YC, Ho SH, Sithambaram S, Tan HJ, Goh KL, and Mahadeva S
- Subjects
- Adult, Aged, Asian People, Cultural Characteristics, Female, Humans, Language, Malaysia, Male, Middle Aged, Predictive Value of Tests, ROC Curve, Reproducibility of Results, Translations, Young Adult, Dyspepsia diagnosis, Dyspepsia ethnology, Psychometrics, Surveys and Questionnaires
- Abstract
Objective: To develop and validate a Mandarin version of the Leeds Dyspepsia Questionnaire (M-LDQ) in Asian patients with dyspepsia., Methods: The M-LDQ was developed according to standardized methods. The validity, internal consistency, test-retest reliability and responsiveness of the instrument were evaluated in both primary and secondary care patients., Results: A total of 184 patients (mean age 54.0 ± 15.8 years, of whom 59% were women and 72.3% of whom had at least secondary level education) were recruited between August 2012 and March 2013, from both primary (n = 100) and secondary care clinics (n = 84). Both the internal consistency of all components of the M-LDQ (Cronbach's α 0.79) and test-retest reliability (Spearman's correlation coefficient 0.78) were good. The M-LDQ was valid in diagnosing dyspepsia in primary care (area under the receiver operating characteristics curve 0.84) and was able to discriminate between secondary and primary care patients (median cumulative LDQ score 13.0 vs 3.0, P < 0.0001). Among eight patients with organic dyspepsia, the median M-LDQ score reduced significantly from 21.0 (pretreatment) to 9.5 (4 weeks post-treatment) (P < 0.0001)., Conclusion: The M-LDQ is a valid and responsive instrument for assessing ethnic Chinese adults with dyspepsia., (© 2014 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.)
- Published
- 2014
- Full Text
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27. Synthesis of single crystal manganese oxide octahedral molecular sieve (OMS) nanostructures with tunable tunnels and shapes.
- Author
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Li WN, Yuan J, Gomez-Mower S, Sithambaram S, and Suib SL
- Abstract
A new and facile route is reported to manipulate the self-assembly synthesis of hierarchically ordered Rb-OMS-2 and pyrolusite with an interesting flowerlike morphology by a direct and mild reaction between rubidium chromateand manganese sulfate without any organic templates. The crystal forms, morphologies, and tunnel sizes of the obtained OMS materials can be controlled. A mechanism for the growth of manganese dioxides with flowerlike architectures was proposed. The obtained products exhibit potential for use in catalysis and other applications.
- Published
- 2006
- Full Text
- View/download PDF
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