39 results on '"H Chheda"'
Search Results
2. Capacity of cdma2000 fixed wireless access system with transmit diversity.
- Author
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Mehmet Yavuz and Ashvin H. Chheda
- Published
- 2001
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3. Power control methods for dedicated control channels during discontinuous transmission in IS-2000 systems.
- Author
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Yiping Wang, David W. Paranchych, and Ashvin H. Chheda
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- 2000
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4. Performance evaluation of two transmit diversity techniques for cdma2000.
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Ashvin H. Chheda and David W. Paranchych
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- 1999
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5. Δ14-STEROIDAL IMPURITY: PREPARATION, CHARACTERIZATION AND EVALUATION, AS WELL DEVELOPMENT OF NEW HPLC METHOD IN DRUG SUBSTANCE LIKE TRIAMCINOLONE HEXACETONIDE
- Author
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Tejas J Shah, Anant R Thakore, Geeta R Desai, Harish S Tandel, and Abhay H Chheda
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Drug ,Chromatography ,Impurity ,Chemistry ,media_common.quotation_subject ,Hplc method ,General Economics, Econometrics and Finance ,Triamcinolone hexacetonide ,media_common - Published
- 2020
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6. On fast forward link power control in CDMA systems.
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A. Jalali and Ashvin H. Chheda
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- 1998
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- View/download PDF
7. A systematic and quantitative evaluation of plantar stimulation: The effect of type, pattern, force of stimulation in eliciting an accurate plantar response
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Satish V Khadilkar and Akash H. Chheda
- Subjects
Adult ,Male ,medicine.medical_specialty ,Weakness ,Rotation ,Plantar surface ,Stimulation ,Stimulus (physiology) ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,medicine ,Humans ,In patient ,030212 general & internal medicine ,medicine.diagnostic_sign ,Reflex, Abnormal ,Foot ,business.industry ,Significant difference ,General Medicine ,Middle Aged ,Reflex, Babinski ,Stroke ,Plantar reflex ,Female ,Surgery ,Neurology (clinical) ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Foot (unit) - Abstract
Objectives Systematic and quantitative evaluation of the plantar reflex has been infrequently studied in the past and can help assess the vexing variables encountered in its elicitation. The objective of this study was to determine the effect of type, pattern and force of stimulation in eliciting an accurate plantar response in patients with pyramidal dysfunction and healthy individuals. Patients and methods A special instrument was designed to give a predesigned force of stimulus. The plantar surface of foot was divided into nine parts and point and stroke stimulations were studied systematically in pyramidal weakness feet (cases) and healthy control feet (controls) with predefined forces. Results were tabulated and statistically analysed. Results Stroke stimulation was superior to point stimulation in eliciting plantar response. There was no significant difference in the responses to the three predefined forces used for stroke stimulations. Sensitivity of Babinski sign was 72.9% and specificity was 100%. In pyramidal weakness feet, extensor responses were significantly elicited from lateral starting stroke patterns (67%) and on moving medially they were replaced by flexor responses (44%). Withdrawal responses increased with the stimulations reaching the distal foot and with the curvilinear component of stimulations. Sensitivity responses (related to the sensitivity of an individual) contaminate the plantar response and occasionally make its interpretation difficult. In subjects with bilateral sensitivity with unilateral disease, knowing the sensitivity pattern on the normal side improved the interpretation of plantar response on the abnormal side. Conclusions Based on this study, the optimal method for eliciting Babinski sign accurately is to stroke the lateral aspect of the sole of the foot in a straight line up to mid foot. This should be performed in both feet three times, and if the weakness is unilateral, it should be performed in the normal leg first to aid interpretation of the affected leg.
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- 2018
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8. Amniotic Fluid as a Rich Source of Mesenchymal Stromal Cells for Transplantation Therapy
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Ivana Antonucci, Liborio Stuppia, Yuji Kaneko, Seongjin Yu, Naoki Tajiri, Eunkyung C. Bae, Sonia H. Chheda, Nathan L. Weinbren, and Cesar V. Borlongan Ph.D.
- Subjects
Medicine - Abstract
Stem cells isolated from amniotic fluid are known to be able to differentiate into different cells types, thus being considered as a powerful tool for cellular therapy of different human diseases. In the last 4 years, amniotic fluid-derived stem (AFS) cells have been shown to express embryonic and adult stem cell markers. These cells can be considered an intermediate stage between embryonic stem cells and adult stem cells. AFS cells can give rise to adipogenic, osteogenic, myogenic, endothelial, neurogenic, and hepatic lineages, inclusive of all embryonic germ layers. AFS cells have a high renewal capacity and can be expanded for over 250 doublings without any detectable loss of chromosomal telomere length. Taken together, all these data provide evidence that amniotic fluid represents a new and very promising source of stem cells for research, as well as clinical applications. Certainly stem cells from amniotic fluid will be useful both for a customized cell supply for newly born children and for banking cells to be used for therapeutic cell transplantation in immunogically matched recipients. Further investigations are also warranted to fully explore the amniotic cells' potential for adult human disorders.
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- 2011
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9. Guidelines versus ground lines: Tuberculosis of the central nervous system
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Satish V, Khadilkar, Nikhil D, Kadam, Rahul V, Kulkarni, Chandrashekhar M, Meshram, Archana R, Meshram, Bhagyadhan A, Patel, and Akash H, Chheda
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Neurology ,Surveys and Questionnaires ,Practice Guidelines as Topic ,Humans ,India ,Neurologists ,Practice Patterns, Physicians' ,Tuberculosis, Central Nervous System - Abstract
This questionnaire-based national survey is aimed at understanding the patterns of practice of various aspects of central nervous system (CNS) tuberculosis (TB) among neurologists.Neurology department of a tertiary medical college.A questionnaire was sent through email to all practicing neurologists in India. The responses were analyzed.Inferential statistics.In all, 144 responses were received (out of the 853 questionnaires sent). The major discrepancies were in the primary antitubercular drug regimen (HRZE + HR), duration for tubercular meningitis (TBM) [12 months] and tuberculoma (12-18 months) to develop, follow-up (varied), linezolid use (varied), proportion of drug-resistant cases (25%), and not taking histological aids (91%). The cerebrospinal fluid (CSF) TB polymerase chain reaction (PCR) utility (75%), not using CSF adenosine deaminase [ADA] (58%), the strategy to stop antitubercular drugs, and the use of steroids (77%) were according to guidelines.The present survey, for the first time, provides ground-level evidence of various aspects of CNS TB as practiced by neurologists in India. The major diversity was observed in therapeutics such as the choice of antitubercular drugs, its duration, linezolid use beyond the recommended duration, and knowledge of drug resistance. The monitoring aspects of CNS TB also showed variations. The investigational aspects of CNS TB such as using TB PCR, not using CSF ADA, and regular neuroimaging revealed a good clinical practice. Other CSF parameters require uniformity. This survey thus helps to identify areas of future work in CNS TB in India.
- Published
- 2019
10. Improved production of natural food preservative ε-poly-l-lysine using a novel producer Bacillus cereus
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Anuj H. Chheda and Madhavi R. Vernekar
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Preservative ,biology ,Lysine ,Bacillus cereus ,chemistry.chemical_element ,Zinc ,One-factor-at-a-time method ,biology.organism_classification ,Biochemistry ,chemistry.chemical_compound ,chemistry ,Yeast extract ,Ammonium ,Fermentation ,Food science ,Food Science - Abstract
An indigenously isolated Bacillus cereus isolated from soil was found to be capable of producing e-poly- l -lysine (e-PL), a homo-poly-amino acid of l -lysine which is used as a safe food preservative. The production of the e-PL was optimized by identifying the most significant components of the medium which affect its production under shake-flask conditions. One factor at a time method was studied for investigation of media components while orthogonal array method was used to determine the optimum composition of various components. The e-PL yield increased significantly from 36.29 mg/l in basal medium to 83.49 mg/l in the optimized medium containing 5% glucose, 1% yeast extract, 1.5% ammonium sulphate, 0.05% magnesium sulphate and 0.004% zinc sulphate. Thus more than two-fold increase in e-PL production was achieved using a novel producer, which by further modifications can be exploited as a potential commercial strain.
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- 2014
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11. Human amniotic epithelial cells express melatonin receptor MT1, but not melatonin receptor MT2: a new perspective to neuroprotection
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Ornella Parolini, Sonia H. Chheda, Naoki Tajiri, Marianna A. Solomita, Nathan L. Weinbren, Seong-Jin Yu, Cesar V. Borlongan, Eunkyung Bae, Takuro Hayashi, and Yuji Kaneko
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medicine.medical_specialty ,education ,respiratory system ,Biology ,Melatonin receptor ,Neuroprotection ,Cell biology ,Melatonin ,Endocrinology ,Amniotic epithelial cells ,Internal medicine ,medicine ,Stem cell ,Receptor ,Melatonin Receptor Type 1B ,hormones, hormone substitutes, and hormone antagonists ,Adult stem cell ,medicine.drug - Abstract
Recent studies have demonstrated that the human placenta is a novel source of adult stem cells. We have provided laboratory evidence that transplantation of these human placenta-derived cells in vitro and in vivo stroke models promotes functional recovery. However, the mechanisms underlying these observed therapeutic benefits of human placenta-derived cells unfortunately remain poorly understood. Here, we examined the expression of two discrete types of melatonin receptors and their roles in proliferation and differentiation of cultured human amniotic epithelial cells (AECs). Cultured AECs express melatonin receptor type 1A (MT1), but not melatonin receptor type 1B (MT2). The proliferation of cultured AECs was increased in the melatonin-treated group in a dose-dependent manner, and the viability of cultured AECs could be further enhanced by melatonin. Moreover, the viability of AECs significantly decreased with H(2) O(2) exposure, which was reversed by pretreatment with melatonin, resulting in increased cell survival rate and cell proliferation. Immunocytochemically, administration of melatonin significantly suppressed nestin proliferation, but enhanced TUJ1 differentiation of MT1-expressing AECs. Additional experiments incorporating antibody blocking and synergistic AEC-melatonin treatments further showed AEC therapeutic benefits via MT1 modulation. Finally, analysis of trophic factors revealed cultured AECs secreted VEGF in the presence of melatonin. These data indicate that melatonin by stimulating MT1 increased cell proliferation and survival rate while enhancing neuronal differentiation of cultured AECs, which together with VEGF upregulation, rendered neuroprotection against experimental in vitro models of ischemic and oxidative stress injury.
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- 2011
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12. Intravenous infusion of GDNF gene-modified human umbilical cord blood CD34+ cells protects against cerebral ischemic injury in spontaneously hypertensive rats
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Sonia H. Chheda, Seong-Jin Yu, Yuji Kaneko, Tianlun Yang, Li Fang, Christine E. Stahl, Cesar V. Borlongan, Eunkyung Bae, Yali Ou, Guolong Yu, Naoki Tajiri, and Kei Hu
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Male ,medicine.medical_specialty ,Time Factors ,animal diseases ,medicine.medical_treatment ,Genetic enhancement ,Green Fluorescent Proteins ,CD34 ,Antigens, CD34 ,Enzyme-Linked Immunosorbent Assay ,Pharmacology ,Transfection ,Brain Ischemia ,Brain ischemia ,Rats, Inbred SHR ,medicine ,Glial cell line-derived neurotrophic factor ,Animals ,Humans ,cardiovascular diseases ,Infusions, Intravenous ,Molecular Biology ,Analysis of Variance ,Behavior, Animal ,biology ,urogenital system ,business.industry ,Brain-Derived Neurotrophic Factor ,Stem Cells ,General Neuroscience ,Stem-cell therapy ,Fetal Blood ,medicine.disease ,Rats ,Surgery ,Transplantation ,Disease Models, Animal ,nervous system ,biology.protein ,Cord Blood Stem Cell Transplantation ,Neurology (clinical) ,Stem cell ,business ,Developmental Biology - Abstract
This study assessed the potential of intravenous transplantation of human umbilical cord blood (HUCB) CD34+ cells transfected with glial cell line-derived neurotrophic factor (GDNF) gene to exert therapeutic benefits in spontaneous hypertensive rats (SHR) exposed to transient middle cerebral artery occlusion (MCAO). SHR with MCAO were randomly assigned to receive intravenously transplantation of vehicle, the plasmid containing the enhanced green fluorescent protein (pEGFP)-CD34+ cells or pEGFP-GDNF-CD34+ cells at 6h after stroke. The CD34+ cells transfected with GDNF gene expressed higher levels of GDNF mRNA and protein than nontransfected HUCB CD34+ cells in vitro. At 28 days after transplantation of GDNF gene modified CD34+ cells, significantly more GFP positive cells, neurons, and astrocytes, likely derived from the grafted cells, populated the peri-infarct area compared to those injected with pEGFP-CD34+ cells or vehicle. Furthermore, the stroke animals transplanted with GDNF gene modified CD34+ cells showed a significant increase in GDNF level in the infarcted hemisphere, reduced brain infarction volume, and enhanced functional recovery compared with those that received pEGFP-CD34+ cells. This study supports the use of a combined gene and stem cell therapy for treating stroke.
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- 2010
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13. Amniotic fluid as a rich source of mesenchymal stromal cells for transplantation therapy
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Yuji Kaneko, Seong-Jin Yu, Sonia H. Chheda, Eunkyung Bae, Nathan L. Weinbren, Cesar V. Borlongan, Ivana Antonucci, Liborio Stuppia, and Naoki Tajiri
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KOSR ,Transplantation ,Amniotic fluid ,Gene Expression Profiling ,lcsh:R ,Biomedical Engineering ,Clinical uses of mesenchymal stem cells ,lcsh:Medicine ,Amniotic stem cells ,Bone Marrow Cells ,Cell Differentiation ,Mesenchymal Stem Cells ,Cell Biology ,Biology ,Telomere ,Amniotic Fluid ,Mesenchymal Stem Cell Transplantation ,Cell biology ,Amniotic epithelial cells ,Immunology ,Humans ,Stem cell ,Adult stem cell ,Stem cell transplantation for articular cartilage repair - Abstract
Stem cells isolated from amniotic fluid are known to be able to differentiate into different cells types, thus being considered as a powerful tool for cellular therapy of different human diseases. In the last 4 years, amniotic fluid-derived stem (AFS) cells have been shown to express embryonic and adult stem cell markers. These cells can be considered an intermediate stage between embryonic stem cells and adult stem cells. AFS cells can give rise to adipogenic, osteogenic, myogenic, endothelial, neurogenic, and hepatic lineages, inclusive of all embryonic germ layers. AFS cells have a high renewal capacity and can be expanded for over 250 doublings without any detectable loss of chromosomal telomere length. Taken together, all these data provide evidence that amniotic fluid represents a new and very promising source of stem cells for research, as well as clinical applications. Certainly stem cells from amniotic fluid will be useful both for a customized cell supply for newly born children and for banking cells to be used for therapeutic cell transplantation in immunogically matched recipients. Further investigations are also warranted to fully explore the amniotic cells' potential for adult human disorders.
- Published
- 2010
14. Peri-hemorrhagic degeneration accompanies stereotaxic collagenase-mediated cortical hemorrhage in mouse
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Yuji Kaneko, Noriyuki Matsukawa, Hideki Hida, Seong-Jin Yu, Nathan L. Weinbren, Cesar V. Borlongan, Naoki Tajiri, Tadashi Masuda, Marianna A. Solomita, Eunkyung Bae, Takao Yasuhara, Sonia H. Chheda, Mina Maki, Sergei A. Kirov, David C. Hess, and Koichi Hara
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Pathology ,medicine.medical_specialty ,Microinjections ,Central nervous system ,Hippocampus ,Striatum ,Stereotaxic Techniques ,Mice ,Cortex (anatomy) ,medicine ,Animals ,Collagenases ,Molecular Biology ,Cerebral Hemorrhage ,Intracerebral hemorrhage ,Cerebral Cortex ,business.industry ,General Neuroscience ,Neurodegeneration ,Anatomy ,medicine.disease ,Mice, Inbred C57BL ,Disease Models, Animal ,medicine.anatomical_structure ,Stereotaxic technique ,Nerve Degeneration ,Neurology (clinical) ,business ,Developmental Biology ,Motor cortex - Abstract
The cortex is a key brain region vulnerable to intracerebral hemorrhage (ICH) associated with stroke and head trauma. Animal models of ICH, via blood or collagenase infusion, have been developed most commonly to target the striatum. Here, we show that stereotaxic injection of collagenase type IV into two sites of the right cortex of adult C57BL6 mice produced hemorrhage to the cortex, subcortical white matter and hippocampus at day 1 post-injury, followed by cortical volume decrement by day 7. Reductions in MAP2- and NeuN-positive neurons were detected at day 1 and 7 post-injury in the core and peri-hemorrhagic cortex, respectively. Fluoro-Jade positive degenerating neurons were observed at day 1 in the peri-hemorrhagic area. An aberrant aggregation of GFAP-positive astrocytes and a significant reduction in RIP-positive oligodendroglial cells were detected at day 7 post-injury in the cortical area. In addition, a significant decrement in retrogradely Cholera Toxin Subunit B-labeled corticospinal neurons was recognized at day 14 post-injury in the ipsilateral cortex. Among the behavioral tests employed, the pole climb movement test robustly detected significant motor dysfunction at day 1, 3, and 7 post-injury that positively but inversely correlated with cortical volume at day 1 and 7 post-injury, respectively. The consistent observation of neuronal cell loss in the hemorrhagic core that subsequently extended to degeneration of neurons in the peri-hemorrhagic area, with accompanying motor abnormalities at least up to the subacute phase, advances this cortical hemorrhage model as a platform for examining the pathophysiology of and experimental treatments for ICH.
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- 2010
15. Reliability of radionuclide scintigraphy for detection of testicular torsion: an animal study
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C A Peto, Alan J. Fischman, H W Strauss, Ahmad M, Robert A. Wilkinson, and H Chheda
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Male ,Scintigraphy ,Vascular occlusion ,Radionuclide angiography ,Scrotum ,Animals ,Medicine ,Testicular torsion ,Tissue Distribution ,Radiology, Nuclear Medicine and imaging ,Spermatic Cord Torsion ,Radionuclide Angiography ,Sodium Pertechnetate Tc 99m ,medicine.diagnostic_test ,business.industry ,Rats, Inbred Strains ,General Medicine ,medicine.disease ,Rats ,Thallium Radioisotopes ,medicine.anatomical_structure ,medicine.symptom ,business ,Nuclear medicine ,Perfusion - Abstract
Sodium pertechnetate Tc99m scintigraphy is a valuable technique for the evaluation of acute testicular torsion in postpubescent males. However, in neonates and children with small testicles, the method is less reliable. Since the testicles of adult rats and young children are of similar size, the reliability of testicular imaging for detecting torsion was evaluated in this species. The utility of the radionuclide angiogram (RA) and static images were determined in 17 anesthetized animals before, 2 h after and 20 h after ligation of the left spermatic cord. The preligation RA was asymmetric in 27% of animals, while the static images were abnormal in 18%. Postligation flow and static images were abnormal in 57% and 82% of the animals (localized to the correct side, 38% and 36%), respectively. The animals with vascular occlusion failed to show any statistically significant greater incidence of decreased radionuclide accumulation on the ligated side. To determine the influence of relative perfusion and extracellular fluid space of the scrotum and testicles on the images, additional studies were performed with 201Tl (representing perfusion) and 99mTcO4- (representing ECF space). Perfusion was approximately equal in the testis and epididymis but significantly higher in the scrotum. These results suggest that scrotal scintigraphy is unreliable for detecting acute torsion of small testicles.
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- 1990
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16. Organophosphorus Poisoning in a Neonate
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H, Chheda Akash, additional, Ashwini, Hiremath, additional, Sandhya, Khadse, additional, Rajesh, Kulkarni, additional, Chhaya, Valvi, additional, and Shobi, Anandi, additional
- Published
- 2014
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17. Comparison of 923 Sestamibi Scans for Primary Hyperparathyroidism with Final Parathyroid Pathology
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N. Mason, Scott F. Gallagher, E.J. Urrutia, H. Chheda, K. Carpenter, Monika M. Wahi, and Krista Haines
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medicine.medical_specialty ,business.industry ,medicine ,Surgery ,Radiology ,medicine.disease ,business ,Primary hyperparathyroidism - Published
- 2010
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18. Minimally invasive parathyroidectomy for primary hyperparathyroidism: decreasing operative time and potential complications while improving cosmetic results
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J, Norman, H, Chheda, and C, Farrell
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Adenoma ,Parathyroidectomy ,Reoperation ,Technetium Tc 99m Sestamibi ,Parathyroid Neoplasms ,Treatment Outcome ,Hyperparathyroidism ,Time and Motion Studies ,Humans ,Minimally Invasive Surgical Procedures ,Prospective Studies ,Length of Stay ,Radionuclide Imaging - Abstract
Primarily because of the lack of highly accurate preoperative localizing studies, the standard operation for primary hyperparathyroidism (HPTH) has consisted of bilateral neck exploration with examination of all four parathyroid glands. Recent experience with the technetium-99m-Sestamibi scan at our hospital has suggested that this single test was now accurate enough to allow unilateral neck exploration. This study was designed to examine the efficacy and safety of minimally invasive parathyroid-ectomy in select patients with a single adenoma demonstrated on a preoperative sestamibi. Eighteen consecutive patients with primary HPTH in whom a sestamibi scan suggested a single adenoma underwent unilateral neck exploration through a 2.5-cm incision, which was extended as necessary. Results were compared to the preceding 25 parathyroid explorations for primary HPTH due to a single adenoma, which were nondirected and included bilateral neck exploration. All patients undergoing minimal exploration were found to have a single adenoma and demonstrated a normal serum calcium within 24 hours of surgery. Standard bilateral exploration failed to locate the adenoma in one patient requiring subsequent re-exploration. Operative time, incision length, and length of hospital stay were all significantly less for those undergoing minimal exploration (all P0.01). There were no complications in either group. Minimally invasive neck exploration is a safe and effective treatment for primary HPTH, is easily accomplished under local anesthesia, and is associated with significant reductions in operative time and hospital stay. Limited exploration provides a better cosmetic result while decreasing the potential complications of bilateral exploration, but is dependent upon a high-quality sestamibi scan.
- Published
- 1998
19. Enhancement of ε-poly-l-lysine (ε-PL) production by a novel producer Bacillus cereus using metabolic precursors and glucose feeding
- Author
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Anuj H. Chheda and Madhavi R. Vernekar
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Lysine ,Metabolic precursors ,Bacillus cereus ,Environmental Science (miscellaneous) ,Biology ,engineering.material ,chemistry.chemical_compound ,Citric acid ,l-Aspartic acid ,TCA cycle ,chemistry.chemical_classification ,biology.organism_classification ,Agricultural and Biological Sciences (miscellaneous) ,Amino acid ,Citric acid cycle ,Biochemistry ,chemistry ,Yield (chemistry) ,Fermentation ,engineering ,Original Article ,Biopolymer ,ε-Poly-l-lysine ,Biotechnology - Abstract
Epsilon poly-l-lysine (e-PL) is a homo-biopolymer with approximately 25–30 l-lysine residues. It is a promising natural biopolymer widely used in food and pharmaceutical industry. The present work reports enhanced production of e-PL with a novel producer Bacillus cereus using amino acids and TCA cycle intermediates in the fermentation medium. Among the various amino acids and TCA cycle intermediates tested 2 mM l-aspartic acid and 5 mM citric acid gave e-PL yield of 145.5 and 230 mg/L, respectively. A combination of citric acid after 24 h and l-aspartic acid after 36 h improved e-PL yield from 85 mg/L (control) to 335 mg/L. Glucose feeding strategy along with metabolic precursors was employed which further enhanced e-PL yield to 565 mg/L. Thus, more than sixfold increase in e-PL yield was achieved suggesting the potential of Bacillus cereus as a novel e-PL producer.
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20. Bayan algorithm: Detecting communities in networks through exact and approximate optimization of modularity.
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Aref S, Mostajabdaveh M, and Chheda H
- Abstract
Community detection is a classic network problem with extensive applications in various fields. Its most common method is using modularity maximization heuristics which rarely return an optimal partition or anything similar. Partitions with globally optimal modularity are difficult to compute, and therefore have been underexplored. Using structurally diverse networks, we compare 30 community detection methods including our proposed algorithm that offers optimality and approximation guarantees: the Bayan algorithm. Unlike existing methods, Bayan globally maximizes modularity or approximates it within a factor. Our results show the distinctive accuracy and stability of maximum-modularity partitions in retrieving planted partitions at rates higher than most alternatives for a wide range of parameter settings in two standard benchmarks. Compared to the partitions from 29 other algorithms, maximum-modularity partitions have the best medians for description length, coverage, performance, average conductance, and well clusteredness. These advantages come at the cost of additional computations which Bayan makes possible for small networks (networks that have up to 3000 edges in their largest connected component). Bayan is several times faster than using open-source and commercial solvers for modularity maximization, making it capable of finding optimal partitions for instances that cannot be optimized by any other existing method. Our results point to a few well-performing algorithms, among which Bayan stands out as the most reliable method for small networks. A python implementation of the Bayan algorithm (bayanpy) is publicly available through the package installer for python.
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- 2024
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21. Extracellular Release of Citrullinated Vimentin Directly Acts on Osteoclasts to Promote Bone Resorption in a Mouse Model of Periodontitis.
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Shindo S, Pierrelus R, Ikeda A, Nakamura S, Heidari A, Pastore MR, Leon E, Ruiz S, Chheda H, Khatiwala R, Kumagai T, Tolson G, Elderbashy I, Ouhara K, Han X, Hernandez M, Vardar-Sengul S, Shiba H, and Kawai T
- Subjects
- Mice, Animals, Osteoclasts metabolism, Disease Models, Animal, NF-kappa B metabolism, Antibodies, Neutralizing metabolism, Alveolar Bone Loss metabolism, Periodontitis metabolism, Arthritis, Rheumatoid
- Abstract
Elevated osteoclast (OC)-mediated bone resorption, a common pathological feature between periodontitis and rheumatoid arthritis (RA), implicates a possible mutually shared pathogenesis. The autoantibody to citrullinated vimentin (CV), a representative biomarker of RA, is reported to promote osteoclastogenesis (OC-genesis). However, its effect on OC-genesis in the context of periodontitis remains to be elucidated. In an in vitro experiment, the addition of exogenous CV upregulated the development of Tartrate-resistant acid phosphatase (TRAP)-positive multinuclear OCs from mouse bone marrow cells and increased the formation of resorption pits. However, Cl-amidine, an irreversible pan-peptidyl arginine deiminase (PAD) inhibitor, suppressed the production and secretion of CV from RANKL-stimulated OC precursors, suggesting that the citrullination of vimentin occurs in OC precursors. On the other hand, the anti-vimentin neutralizing antibody suppressed in vitro Receptor activator of nuclear factor kappa-Β ligand (RANKL)-induced OC-genesis. The CV-induced upregulation of OC-genesis was abrogated by the Protein kinase C (PKC)-δ inhibitor Rottlerin, accompanied by the downmodulation of OC-genesis-related genes, including Osteoclast stimulatory transmembrane protein (OC-STAMP), TRAP and Matrix Metallopeptidase 9 (MMP9) as well as extracellular signal-regulated kinase (ERK) mitogen-activated protein (MAP)-kinase phosphorylation. Elevated levels of soluble CV and vimentin-bearing mononuclear cells were found in the bone resorption lesions of periodontitis induced in mice in the absence of an anti-CV antibody. Finally, local injection of anti-vimentin neutralizing antibody suppressed the periodontal bone loss induced in mice. Collectively, these results indicated that the extracellular release of CV promoted OC-genesis and bone resorption in periodontitis.
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- 2023
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22. Genetic and functional implications of an exonic TRIM55 variant in heart failure.
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Heliste J, Chheda H, Paatero I, Salminen TA, Akimov Y, Paavola J, Elenius K, and Aittokallio T
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- Actinin metabolism, Animals, Base Sequence, Calcium metabolism, Cardiomegaly complications, Cardiomegaly genetics, Cardiomegaly pathology, Cell Cycle, Cell Line, Cell Survival, Chromosomes, Human, Pair 8 genetics, Cohort Studies, Embryo, Nonmammalian metabolism, Finland, Gene Expression Regulation, Heart Failure physiopathology, Humans, Myocardial Contraction genetics, Myocytes, Cardiac metabolism, Myocytes, Cardiac pathology, Sequestosome-1 Protein metabolism, Serum Response Factor metabolism, Stress, Physiological genetics, Zebrafish embryology, Exons genetics, Genetic Variation, Heart Failure genetics, Tripartite Motif Proteins genetics
- Abstract
Background: To tackle the missing heritability of sporadic heart failure, we screened for novel heart failure-associated genetic variants in the Finnish population and functionally characterized a novel variant in vitro and in vivo., Methods and Results: Heart failure-associated variants were screened in genotyping array data of the FINRISK study, consisting of 994 cases and 20,118 controls. Based on logistic regression analysis, a potentially damaging variant in TRIM55 (rs138811034), encoding an E140K variant, was selected for validations. In HL-1 cardiomyocytes, we used CRISPR/Cas9 technology to introduce the variant in the endogenous locus, and additionally TRIM55 wildtype or E140K was overexpressed from plasmid. Functional responses were profiled using whole-genome RNA sequencing, RT-PCR and Western analyses, cell viability and cell cycle assays and cell surface area measurements. In zebrafish embryos, cardiac contractility was measured using videomicroscopy after CRISPR-mediated knockout of trim55a or plasmid overexpression of TRIM55 WT or E140K. Genes related to muscle contraction and cardiac stress were highly regulated in Trim55 E140K/- cardiomyocytes. When compared to the WT/WT cells, the variant cells demonstrated reduced viability, significant hypertrophic response to isoproterenol, p21 protein overexpression and impaired cell cycle progression. In zebrafish embryos, the deletion of trim55a or overexpression of TRIM55 E140K reduced cardiac contractility as compared to embryos with wildtype genotype or overexpression of WT TRIM55, respectively., Conclusions: A previously uncharacterized TRIM55 E140K variant demonstrated a number of functional implications for cardiomyocyte functions in vitro and in vivo. These findings suggest a novel role for TRIM55 polymorphism in predisposing to heart failure., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
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- 2020
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23. Immune cell contexture in the bone marrow tumor microenvironment impacts therapy response in CML.
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Brück O, Blom S, Dufva O, Turkki R, Chheda H, Ribeiro A, Kovanen P, Aittokallio T, Koskenvesa P, Kallioniemi O, Porkka K, Pellinen T, and Mustjoki S
- Subjects
- Adult, Aged, Aged, 80 and over, Biomarkers, Biopsy, Female, Flow Cytometry, Histocompatibility Antigens Class I immunology, Humans, Immunohistochemistry, Immunomodulation, Leukemia, Myelogenous, Chronic, BCR-ABL Positive therapy, Leukocyte Count, Lymphocyte Count, Male, Middle Aged, Myeloid-Derived Suppressor Cells immunology, Myeloid-Derived Suppressor Cells metabolism, Protein Kinase Inhibitors administration & dosage, Protein Kinase Inhibitors adverse effects, Protein Kinase Inhibitors therapeutic use, T-Lymphocyte Subsets immunology, T-Lymphocyte Subsets metabolism, T-Lymphocytes metabolism, T-Lymphocytes pathology, Tissue Array Analysis, Treatment Outcome, Young Adult, Bone Marrow immunology, Bone Marrow pathology, Leukemia, Myelogenous, Chronic, BCR-ABL Positive immunology, Leukemia, Myelogenous, Chronic, BCR-ABL Positive pathology, T-Lymphocytes immunology, Tumor Microenvironment immunology
- Abstract
Increasing evidence suggests that the immune system affects prognosis of chronic myeloid leukemia (CML), but the detailed immunological composition of the leukemia bone marrow (BM) microenvironment is unknown. We aimed to characterize the immune landscape of the CML BM and predict the current treatment goal of tyrosine kinase inhibitor (TKI) therapy, molecular remission 4.0 (MR4.0). Using multiplex immunohistochemistry (mIHC) and automated image analysis, we studied BM tissues of CML patients (n = 56) and controls (n = 14) with a total of 30 immunophenotype markers essential in cancer immunology. CML patients' CD4+ and CD8+ T-cells expressed higher levels of putative exhaustion markers PD1, TIM3, and CTLA4 when compared to control. PD1 expression was higher in BM compared to paired peripheral blood (PB) samples, and decreased during TKI therapy. By combining clinical parameters and immune profiles, low CD4+ T-cell proportion, high proportion of PD1+TIM3-CD8+ T cells, and high PB neutrophil count were most predictive of lower MR4.0 likelihood. Low CD4+ T-cell proportion and high PB neutrophil counts predicted MR4.0 also in a validation cohort (n = 52) analyzed with flow cytometry. In summary, the CML BM is characterized by immune suppression and immune biomarkers predicted MR4.0, thus warranting further testing of immunomodulatory drugs in CML treatment.
- Published
- 2018
- Full Text
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24. An Expanded Genome-Wide Association Study of Type 2 Diabetes in Europeans.
- Author
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Scott RA, Scott LJ, Mägi R, Marullo L, Gaulton KJ, Kaakinen M, Pervjakova N, Pers TH, Johnson AD, Eicher JD, Jackson AU, Ferreira T, Lee Y, Ma C, Steinthorsdottir V, Thorleifsson G, Qi L, Van Zuydam NR, Mahajan A, Chen H, Almgren P, Voight BF, Grallert H, Müller-Nurasyid M, Ried JS, Rayner NW, Robertson N, Karssen LC, van Leeuwen EM, Willems SM, Fuchsberger C, Kwan P, Teslovich TM, Chanda P, Li M, Lu Y, Dina C, Thuillier D, Yengo L, Jiang L, Sparso T, Kestler HA, Chheda H, Eisele L, Gustafsson S, Frånberg M, Strawbridge RJ, Benediktsson R, Hreidarsson AB, Kong A, Sigurðsson G, Kerrison ND, Luan J, Liang L, Meitinger T, Roden M, Thorand B, Esko T, Mihailov E, Fox C, Liu CT, Rybin D, Isomaa B, Lyssenko V, Tuomi T, Couper DJ, Pankow JS, Grarup N, Have CT, Jørgensen ME, Jørgensen T, Linneberg A, Cornelis MC, van Dam RM, Hunter DJ, Kraft P, Sun Q, Edkins S, Owen KR, Perry JRB, Wood AR, Zeggini E, Tajes-Fernandes J, Abecasis GR, Bonnycastle LL, Chines PS, Stringham HM, Koistinen HA, Kinnunen L, Sennblad B, Mühleisen TW, Nöthen MM, Pechlivanis S, Baldassarre D, Gertow K, Humphries SE, Tremoli E, Klopp N, Meyer J, Steinbach G, Wennauer R, Eriksson JG, Mӓnnistö S, Peltonen L, Tikkanen E, Charpentier G, Eury E, Lobbens S, Gigante B, Leander K, McLeod O, Bottinger EP, Gottesman O, Ruderfer D, Blüher M, Kovacs P, Tonjes A, Maruthur NM, Scapoli C, Erbel R, Jöckel KH, Moebus S, de Faire U, Hamsten A, Stumvoll M, Deloukas P, Donnelly PJ, Frayling TM, Hattersley AT, Ripatti S, Salomaa V, Pedersen NL, Boehm BO, Bergman RN, Collins FS, Mohlke KL, Tuomilehto J, Hansen T, Pedersen O, Barroso I, Lannfelt L, Ingelsson E, Lind L, Lindgren CM, Cauchi S, Froguel P, Loos RJF, Balkau B, Boeing H, Franks PW, Barricarte Gurrea A, Palli D, van der Schouw YT, Altshuler D, Groop LC, Langenberg C, Wareham NJ, Sijbrands E, van Duijn CM, Florez JC, Meigs JB, Boerwinkle E, Gieger C, Strauch K, Metspalu A, Morris AD, Palmer CNA, Hu FB, Thorsteinsdottir U, Stefansson K, Dupuis J, Morris AP, Boehnke M, McCarthy MI, and Prokopenko I
- Subjects
- Genetic Variation, Humans, Diabetes Mellitus, Type 2 genetics, Gene Expression Regulation physiology, Genome-Wide Association Study, White People
- Abstract
To characterize type 2 diabetes (T2D)-associated variation across the allele frequency spectrum, we conducted a meta-analysis of genome-wide association data from 26,676 T2D case and 132,532 control subjects of European ancestry after imputation using the 1000 Genomes multiethnic reference panel. Promising association signals were followed up in additional data sets (of 14,545 or 7,397 T2D case and 38,994 or 71,604 control subjects). We identified 13 novel T2D-associated loci ( P < 5 × 10
-8 ), including variants near the GLP2R , GIP , and HLA-DQA1 genes. Our analysis brought the total number of independent T2D associations to 128 distinct signals at 113 loci. Despite substantially increased sample size and more complete coverage of low-frequency variation, all novel associations were driven by common single nucleotide variants. Credible sets of potentially causal variants were generally larger than those based on imputation with earlier reference panels, consistent with resolution of causal signals to common risk haplotypes. Stratification of T2D-associated loci based on T2D-related quantitative trait associations revealed tissue-specific enrichment of regulatory annotations in pancreatic islet enhancers for loci influencing insulin secretion and in adipocytes, monocytes, and hepatocytes for insulin action-associated loci. These findings highlight the predominant role played by common variants of modest effect and the diversity of biological mechanisms influencing T2D pathophysiology., (© 2017 by the American Diabetes Association.)- Published
- 2017
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25. Enrichment of low-frequency functional variants revealed by whole-genome sequencing of multiple isolated European populations.
- Author
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Xue Y, Mezzavilla M, Haber M, McCarthy S, Chen Y, Narasimhan V, Gilly A, Ayub Q, Colonna V, Southam L, Finan C, Massaia A, Chheda H, Palta P, Ritchie G, Asimit J, Dedoussis G, Gasparini P, Palotie A, Ripatti S, Soranzo N, Toniolo D, Wilson JF, Durbin R, Tyler-Smith C, and Zeggini E
- Subjects
- Gene Frequency, Genetic Variation, Genetics, Population, Humans, Polymorphism, Single Nucleotide, Whole Genome Sequencing, Genome, Human, White People genetics
- Abstract
The genetic features of isolated populations can boost power in complex-trait association studies, and an in-depth understanding of how their genetic variation has been shaped by their demographic history can help leverage these advantageous characteristics. Here, we perform a comprehensive investigation using 3,059 newly generated low-depth whole-genome sequences from eight European isolates and two matched general populations, together with published data from the 1000 Genomes Project and UK10K. Sequencing data give deeper and richer insights into population demography and genetic characteristics than genotype-chip data, distinguishing related populations more effectively and allowing their functional variants to be studied more fully. We demonstrate relaxation of purifying selection in the isolates, leading to enrichment of rare and low-frequency functional variants, using novel statistics, DVxy and SVxy. We also develop an isolation-index (Isx) that predicts the overall level of such key genetic characteristics and can thus help guide population choice in future complex-trait association studies.
- Published
- 2017
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26. Whole-genome view of the consequences of a population bottleneck using 2926 genome sequences from Finland and United Kingdom.
- Author
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Chheda H, Palta P, Pirinen M, McCarthy S, Walter K, Koskinen S, Salomaa V, Daly M, Durbin R, Palotie A, Aittokallio T, and Ripatti S
- Subjects
- Conserved Sequence, Finland, Genome, Human, Humans, Mutation Rate, United Kingdom, Genome-Wide Association Study standards, Polymorphism, Genetic, Population genetics
- Abstract
Isolated populations with enrichment of variants due to recent population bottlenecks provide a powerful resource for identifying disease-associated genetic variants and genes. As a model of an isolate population, we sequenced the genomes of 1463 Finnish individuals as part of the Sequencing Initiative Suomi (SISu) Project. We compared the genomic profiles of the 1463 Finns to a sample of 1463 British individuals that were sequenced in parallel as part of the UK10K Project. Whereas there were no major differences in the allele frequency of common variants, a significant depletion of variants in the rare frequency spectrum was observed in Finns when comparing the two populations. On the other hand, we observed >2.1 million variants that were twice as frequent among Finns compared with Britons and 800 000 variants that were more than 10 times more frequent in Finns. Furthermore, in Finns we observed a relative proportional enrichment of variants in the minor allele frequency range between 2 and 5% (P<2.2 × 10
-16 ). When stratified by their functional annotations, loss-of-function variants showed the highest proportional enrichment in Finns (P=0.0291). In the non-coding part of the genome, variants in conserved regions (P=0.002) and promoters (P=0.01) were also significantly enriched in the Finnish samples. These functional categories represent the highest a priori power for downstream association studies of rare variants using population isolates.- Published
- 2017
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27. Erratum: Crowdsourced assessment of common genetic contribution to predicting anti-TNF treatment response in rheumatoid arthritis.
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Sieberts SK, Zhu F, García-García J, Stahl E, Pratap A, Pandey G, Pappas D, Aguilar D, Anton B, Bonet J, Eksi R, Fornés O, Guney E, Li H, Marín MA, Panwar B, Planas-Iglesias J, Poglayen D, Cui J, Falcao AO, Suver C, Hoff B, Balagurusamy VSK, Dillenberger D, Neto EC, Norman T, Aittokallio T, Ammad-Ud-Din M, Azencott CA, Bellón V, Boeva V, Bunte K, Chheda H, Cheng L, Corander J, Dumontier M, Goldenberg A, Gopalacharyulu P, Hajiloo M, Hidru D, Jaiswal A, Kaski S, Khalfaoui B, Khan SA, Kramer ER, Marttinen P, Mezlini AM, Molparia B, Pirinen M, Saarela J, Samwald M, Stoven V, Tang H, Tang J, Torkamani A, Vert JP, Wang B, Wang T, Wennerberg K, Wineinger NE, Xiao G, Xie Y, Yeung R, Zhan X, Zhao C, Greenberg J, Kremer J, Michaud K, Barton A, Coenen M, Mariette X, Miceli C, Shadick N, Weinblatt M, de Vries N, Tak PP, Gerlag D, Huizinga TWJ, Kurreeman F, Allaart CF, Bridges SL Jr, Criswell L, Moreland L, Klareskog L, Saevarsdottir S, Padyukov L, Gregersen PK, Friend S, Plenge R, Stolovitzky G, Oliva B, Guan Y, and Mangravite LM
- Published
- 2016
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28. Crowdsourced assessment of common genetic contribution to predicting anti-TNF treatment response in rheumatoid arthritis.
- Author
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Sieberts SK, Zhu F, García-García J, Stahl E, Pratap A, Pandey G, Pappas D, Aguilar D, Anton B, Bonet J, Eksi R, Fornés O, Guney E, Li H, Marín MA, Panwar B, Planas-Iglesias J, Poglayen D, Cui J, Falcao AO, Suver C, Hoff B, Balagurusamy VSK, Dillenberger D, Neto EC, Norman T, Aittokallio T, Ammad-Ud-Din M, Azencott CA, Bellón V, Boeva V, Bunte K, Chheda H, Cheng L, Corander J, Dumontier M, Goldenberg A, Gopalacharyulu P, Hajiloo M, Hidru D, Jaiswal A, Kaski S, Khalfaoui B, Khan SA, Kramer ER, Marttinen P, Mezlini AM, Molparia B, Pirinen M, Saarela J, Samwald M, Stoven V, Tang H, Tang J, Torkamani A, Vert JP, Wang B, Wang T, Wennerberg K, Wineinger NE, Xiao G, Xie Y, Yeung R, Zhan X, Zhao C, Greenberg J, Kremer J, Michaud K, Barton A, Coenen M, Mariette X, Miceli C, Shadick N, Weinblatt M, de Vries N, Tak PP, Gerlag D, Huizinga TWJ, Kurreeman F, Allaart CF, Louis Bridges S Jr, Criswell L, Moreland L, Klareskog L, Saevarsdottir S, Padyukov L, Gregersen PK, Friend S, Plenge R, Stolovitzky G, Oliva B, Guan Y, and Mangravite LM
- Subjects
- Adult, Aged, Antibodies, Monoclonal therapeutic use, Antirheumatic Agents therapeutic use, Arthritis, Rheumatoid genetics, Arthritis, Rheumatoid pathology, Certolizumab Pegol therapeutic use, Cohort Studies, Crowdsourcing, Female, Humans, Male, Middle Aged, Prognosis, Treatment Outcome, Tumor Necrosis Factor-alpha immunology, Antibodies, Monoclonal, Humanized therapeutic use, Arthritis, Rheumatoid drug therapy, Genetic Predisposition to Disease genetics, Polymorphism, Single Nucleotide, Tumor Necrosis Factor-alpha antagonists & inhibitors
- Abstract
Rheumatoid arthritis (RA) affects millions world-wide. While anti-TNF treatment is widely used to reduce disease progression, treatment fails in ∼one-third of patients. No biomarker currently exists that identifies non-responders before treatment. A rigorous community-based assessment of the utility of SNP data for predicting anti-TNF treatment efficacy in RA patients was performed in the context of a DREAM Challenge (http://www.synapse.org/RA_Challenge). An open challenge framework enabled the comparative evaluation of predictions developed by 73 research groups using the most comprehensive available data and covering a wide range of state-of-the-art modelling methodologies. Despite a significant genetic heritability estimate of treatment non-response trait (h(2)=0.18, P value=0.02), no significant genetic contribution to prediction accuracy is observed. Results formally confirm the expectations of the rheumatology community that SNP information does not significantly improve predictive performance relative to standard clinical traits, thereby justifying a refocusing of future efforts on collection of other data.
- Published
- 2016
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29. Rare loss-of-function variants in SETD1A are associated with schizophrenia and developmental disorders.
- Author
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Singh T, Kurki MI, Curtis D, Purcell SM, Crooks L, McRae J, Suvisaari J, Chheda H, Blackwood D, Breen G, Pietiläinen O, Gerety SS, Ayub M, Blyth M, Cole T, Collier D, Coomber EL, Craddock N, Daly MJ, Danesh J, DiForti M, Foster A, Freimer NB, Geschwind D, Johnstone M, Joss S, Kirov G, Körkkö J, Kuismin O, Holmans P, Hultman CM, Iyegbe C, Lönnqvist J, Männikkö M, McCarroll SA, McGuffin P, McIntosh AM, McQuillin A, Moilanen JS, Moore C, Murray RM, Newbury-Ecob R, Ouwehand W, Paunio T, Prigmore E, Rees E, Roberts D, Sambrook J, Sklar P, St Clair D, Veijola J, Walters JT, Williams H, Sullivan PF, Hurles ME, O'Donovan MC, Palotie A, Owen MJ, and Barrett JC
- Subjects
- Case-Control Studies, Cohort Studies, Female, Finland epidemiology, Genetic Predisposition to Disease epidemiology, Genetic Predisposition to Disease genetics, Humans, Male, Neurodevelopmental Disorders diagnosis, Neurodevelopmental Disorders epidemiology, Schizophrenia diagnosis, Schizophrenia epidemiology, Genetic Association Studies methods, Genetic Variation genetics, Histone-Lysine N-Methyltransferase genetics, Neurodevelopmental Disorders genetics, Schizophrenia genetics
- Abstract
By analyzing the whole-exome sequences of 4,264 schizophrenia cases, 9,343 controls and 1,077 trios, we identified a genome-wide significant association between rare loss-of-function (LoF) variants in SETD1A and risk for schizophrenia (P = 3.3 × 10(-9)). We found only two heterozygous LoF variants in 45,376 exomes from individuals without a neuropsychiatric diagnosis, indicating that SETD1A is substantially depleted of LoF variants in the general population. Seven of the ten individuals with schizophrenia carrying SETD1A LoF variants also had learning difficulties. We further identified four SETD1A LoF carriers among 4,281 children with severe developmental disorders and two more carriers in an independent sample of 5,720 Finnish exomes, both with notable neuropsychiatric phenotypes. Together, our observations indicate that LoF variants in SETD1A cause a range of neurodevelopmental disorders, including schizophrenia. Combining these data with previous common variant evidence, we suggest that epigenetic dysregulation, specifically in the histone H3K4 methylation pathway, is an important mechanism in the pathogenesis of schizophrenia.
- Published
- 2016
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30. Genetic fine mapping and genomic annotation defines causal mechanisms at type 2 diabetes susceptibility loci.
- Author
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Gaulton KJ, Ferreira T, Lee Y, Raimondo A, Mägi R, Reschen ME, Mahajan A, Locke A, Rayner NW, Robertson N, Scott RA, Prokopenko I, Scott LJ, Green T, Sparso T, Thuillier D, Yengo L, Grallert H, Wahl S, Frånberg M, Strawbridge RJ, Kestler H, Chheda H, Eisele L, Gustafsson S, Steinthorsdottir V, Thorleifsson G, Qi L, Karssen LC, van Leeuwen EM, Willems SM, Li M, Chen H, Fuchsberger C, Kwan P, Ma C, Linderman M, Lu Y, Thomsen SK, Rundle JK, Beer NL, van de Bunt M, Chalisey A, Kang HM, Voight BF, Abecasis GR, Almgren P, Baldassarre D, Balkau B, Benediktsson R, Blüher M, Boeing H, Bonnycastle LL, Bottinger EP, Burtt NP, Carey J, Charpentier G, Chines PS, Cornelis MC, Couper DJ, Crenshaw AT, van Dam RM, Doney AS, Dorkhan M, Edkins S, Eriksson JG, Esko T, Eury E, Fadista J, Flannick J, Fontanillas P, Fox C, Franks PW, Gertow K, Gieger C, Gigante B, Gottesman O, Grant GB, Grarup N, Groves CJ, Hassinen M, Have CT, Herder C, Holmen OL, Hreidarsson AB, Humphries SE, Hunter DJ, Jackson AU, Jonsson A, Jørgensen ME, Jørgensen T, Kao WH, Kerrison ND, Kinnunen L, Klopp N, Kong A, Kovacs P, Kraft P, Kravic J, Langford C, Leander K, Liang L, Lichtner P, Lindgren CM, Lindholm E, Linneberg A, Liu CT, Lobbens S, Luan J, Lyssenko V, Männistö S, McLeod O, Meyer J, Mihailov E, Mirza G, Mühleisen TW, Müller-Nurasyid M, Navarro C, Nöthen MM, Oskolkov NN, Owen KR, Palli D, Pechlivanis S, Peltonen L, Perry JR, Platou CG, Roden M, Ruderfer D, Rybin D, van der Schouw YT, Sennblad B, Sigurðsson G, Stančáková A, Steinbach G, Storm P, Strauch K, Stringham HM, Sun Q, Thorand B, Tikkanen E, Tonjes A, Trakalo J, Tremoli E, Tuomi T, Wennauer R, Wiltshire S, Wood AR, Zeggini E, Dunham I, Birney E, Pasquali L, Ferrer J, Loos RJ, Dupuis J, Florez JC, Boerwinkle E, Pankow JS, van Duijn C, Sijbrands E, Meigs JB, Hu FB, Thorsteinsdottir U, Stefansson K, Lakka TA, Rauramaa R, Stumvoll M, Pedersen NL, Lind L, Keinanen-Kiukaanniemi SM, Korpi-Hyövälti E, Saaristo TE, Saltevo J, Kuusisto J, Laakso M, Metspalu A, Erbel R, Jöcke KH, Moebus S, Ripatti S, Salomaa V, Ingelsson E, Boehm BO, Bergman RN, Collins FS, Mohlke KL, Koistinen H, Tuomilehto J, Hveem K, Njølstad I, Deloukas P, Donnelly PJ, Frayling TM, Hattersley AT, de Faire U, Hamsten A, Illig T, Peters A, Cauchi S, Sladek R, Froguel P, Hansen T, Pedersen O, Morris AD, Palmer CN, Kathiresan S, Melander O, Nilsson PM, Groop LC, Barroso I, Langenberg C, Wareham NJ, O'Callaghan CA, Gloyn AL, Altshuler D, Boehnke M, Teslovich TM, McCarthy MI, and Morris AP
- Subjects
- Binding Sites, Case-Control Studies, Chromatin Immunoprecipitation, Gene Expression Regulation, Genome-Wide Association Study, Genomics, Hepatocyte Nuclear Factor 3-beta metabolism, Humans, Islets of Langerhans metabolism, Islets of Langerhans pathology, Liver metabolism, Liver pathology, Molecular Sequence Annotation, Receptor, Melatonin, MT2 metabolism, Chromosome Mapping, Diabetes Mellitus, Type 2 genetics, Genetic Loci, Genetic Predisposition to Disease, Hepatocyte Nuclear Factor 3-beta genetics, Polymorphism, Single Nucleotide genetics, Receptor, Melatonin, MT2 genetics
- Abstract
We performed fine mapping of 39 established type 2 diabetes (T2D) loci in 27,206 cases and 57,574 controls of European ancestry. We identified 49 distinct association signals at these loci, including five mapping in or near KCNQ1. 'Credible sets' of the variants most likely to drive each distinct signal mapped predominantly to noncoding sequence, implying that association with T2D is mediated through gene regulation. Credible set variants were enriched for overlap with FOXA2 chromatin immunoprecipitation binding sites in human islet and liver cells, including at MTNR1B, where fine mapping implicated rs10830963 as driving T2D association. We confirmed that the T2D risk allele for this SNP increases FOXA2-bound enhancer activity in islet- and liver-derived cells. We observed allele-specific differences in NEUROD1 binding in islet-derived cells, consistent with evidence that the T2D risk allele increases islet MTNR1B expression. Our study demonstrates how integration of genetic and genomic information can define molecular mechanisms through which variants underlying association signals exert their effects on disease.
- Published
- 2015
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31. Targeted resequencing of the pericentromere of chromosome 2 linked to constitutional delay of growth and puberty.
- Author
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Cousminer DL, Leinonen JT, Sarin AP, Chheda H, Surakka I, Wehkalampi K, Ellonen P, Ripatti S, Dunkel L, Palotie A, and Widén E
- Subjects
- Adolescent, Exome, Female, Genome, Human, Humans, Male, Pedigree, Sequence Analysis, DNA, Centromere, Chromosomes, Human, Pair 2, Growth genetics, Puberty genetics
- Abstract
Constitutional delay of growth and puberty (CDGP) is the most common cause of pubertal delay. CDGP is defined as the proportion of the normal population who experience pubertal onset at least 2 SD later than the population mean, representing 2.3% of all adolescents. While adolescents with CDGP spontaneously enter puberty, they are at risk for short stature, decreased bone mineral density, and psychosocial problems. Genetic factors contribute heavily to the timing of puberty, but the vast majority of CDGP cases remain biologically unexplained, and there is no definitive test to distinguish CDGP from pathological absence of puberty during adolescence. Recently, we published a study identifying significant linkage between a locus at the pericentromeric region of chromosome 2 (chr 2) and CDGP in Finnish families. To investigate this region for causal variation, we sequenced chr 2 between the genomic coordinates of 79-124 Mb (genome build GRCh37) in the proband and affected parent of the 13 families contributing most to this linkage signal. One gene, DNAH6, harbored 6 protein-altering low-frequency variants (< 6% in the Finnish population) in 10 of the CDGP probands. We sequenced an additional 135 unrelated Finnish CDGP subjects and utilized the unique Sequencing Initiative Suomi (SISu) population reference exome set to show that while 5 of these variants were present in the CDGP set, they were also present in the Finnish population at similar frequencies. Additional variants in the targeted region could not be prioritized for follow-up, possibly due to gaps in sequencing coverage or lack of functional knowledge of non-genic genomic regions. Thus, despite having a well-characterized sample collection from a genetically homogeneous population with a large population-based reference sequence dataset, we were unable to pinpoint variation in the linked region predisposing delayed puberty. This study highlights the difficulties of detecting genetic variants under linkage regions for complex traits and suggests that advancements in annotation of gene function and regulatory regions of the genome will be critical for solving the genetic background of complex phenotypes like CDGP.
- Published
- 2015
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32. Comparative performance of flat sheet and spiral wound modules in the nanofiltration of reactive dye solution.
- Author
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Patel TM, Chheda H, Baheti A, Patel P, and Nath K
- Subjects
- Coloring Agents chemistry, Electric Conductivity, Membranes, Artificial, Oxidation-Reduction, Sodium Chloride chemistry, Time Factors, Filtration instrumentation, Nanostructures chemistry, Naphthalenesulfonates chemistry, Triazines chemistry, Water Pollutants, Chemical chemistry, Water Purification instrumentation
- Abstract
Background and Purpose: Besides the opportunities for reuse, stringent regulations and growing public awareness demand an enhanced quality of effluent from dye industries. Treatment of an aqueous solution of dye (reactive red 198) was carried out in a nanofiltration unit using both flat sheet and spiral wound modules to obtain a comparative performance evaluation in terms of permeate flux and quality., Methods: Hydrophilized polyamide membrane with molecular weight cutoff of 150 was used for the experiments. Effects of trans-membrane pressure (TMP), feed concentration and addition of salt on permeate flux were investigated. Percent reduction of color, chemical oxygen demand (COD), total dissolved solid (TDS), and conductivity were determined to assess performance of the membrane., Results: The maximum flux decline was 16.1% of its initial value at 490 kPa TMP with 50 ppm feed concentration in spiral wound module, whereas the same in flat sheet under same conditions was 7.2%. The effect of TMP showed a quasi-linear increase in flux with increasing pressure. Increased permeate concentration led to the reduction in observed retention of dye in the membrane. The average reduction in color, COD, and TDS were 96.88%, 97.38%, and 89.24%, respectively. The decline in permeate flux was more in case of spiral wound module compared to flat sheet. However, spiral wound module performed better in terms of color removal, COD reduction, and TDS removal., Conclusion: Substantial removal of color was achieved in the nanofiltration experiments with a marked reduction in COD and TDS. The process allowed the production of permeate stream with great reutilization possibilities.
- Published
- 2011
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33. False positive stress-test in a patient with pericardial effusion.
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Mateja C, Mishkin J, George M, Chheda H, and Guglin M
- Subjects
- Cardiac Tamponade diagnosis, Cardiac Tamponade physiopathology, Diagnosis, Differential, False Positive Reactions, Humans, Male, Middle Aged, Exercise Test standards, Pericardial Effusion diagnosis, Pericardial Effusion physiopathology
- Abstract
We report a case of false positive stress test in a patient with cardiac tamponade. After the drainage of pericardial effusion, reversible defect on a stress test resolved. Cardiac catheterization revealed normal coronary arteries.
- Published
- 2009
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34. 32P as an adjunct to standard therapy for locally advanced unresectable pancreatic cancer: a randomized trial.
- Author
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Rosemurgy A, Luzardo G, Cooper J, Bowers C, Zervos E, Bloomston M, Al-Saadi S, Carroll R, Chheda H, Carey L, Goldin S, Grundy S, Kudryk B, Zwiebel B, Black T, Briggs J, and Chervenick P
- Subjects
- Adenocarcinoma drug therapy, Adenocarcinoma pathology, Aged, Female, Fluorouracil therapeutic use, Humans, Male, Middle Aged, Pancreatic Neoplasms drug therapy, Pancreatic Neoplasms pathology, Phosphorus Radioisotopes administration & dosage, Phosphorus Radioisotopes adverse effects, Prospective Studies, Treatment Outcome, Adenocarcinoma radiotherapy, Pancreatic Neoplasms radiotherapy, Phosphorus Radioisotopes therapeutic use
- Abstract
This prospective randomized trial was undertaken to determine the added efficacy of (32)P in treating locally advanced unresectable pancreatic cancer. Thirty patients with biopsy proven locally advanced unresectable adenocarcinoma of the pancreas were assessable after receiving 5-fluorouracil and radiation therapy with or without (32)P, followed by gemcitabine. Intratumoral (32)P dose was determined by tumor size and volume and was administered at months 0, 1, 2, 6, 7, and 8. Tumor cross-sectional area and liquefaction were determined at intervals by computed tomography scan. Tumor liquefaction occurred in 78% of patients receiving (32)P and in 8% of patients not receiving (32)P, although tumor cross-sectional area did not decrease. Serious adverse events occurred more often per patient for patients receiving (32)P (4.2 +/- 3.1 vs. 1.8 +/- 1.9; p = 0.03) leading to more hospitalizations. Death was because of disease progression (23 patients), gastrointenstinal hemorrhage (4 patients), and stroke (1 patient). One patient not receiving (32)P and one receiving (32)P are alive at 28 and 13 months, respectively. (32)P did not prolong survival (7.4 +/- 5.5 months with (32)P vs. 11.5 +/- 8.0 months without (32)P, p = 0.16). (32)P promoted tumor liquefaction, but did not decrease tumor size. Intratumoral (32)P was associated with more serious adverse events and did not improve survival for locally advanced unresectable pancreatic cancer.
- Published
- 2008
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35. The false-positive parathyroid sestamibi: a real or perceived problem and a case for radioguided parathyroidectomy.
- Author
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Norman JG, Jaffray CE, and Chheda H
- Subjects
- Adenoma diagnostic imaging, False Positive Reactions, Gamma Cameras, Humans, Hyperparathyroidism diagnostic imaging, Minimally Invasive Surgical Procedures, Monitoring, Intraoperative, Parathyroid Neoplasms diagnostic imaging, Radionuclide Imaging, Reoperation, Treatment Outcome, Adenoma surgery, Hyperparathyroidism surgery, Parathyroid Neoplasms surgery, Parathyroidectomy methods, Technetium Tc 99m Sestamibi
- Abstract
Objective: To demonstrate that the positive parathyroid sestamibi scan, if correctly interpreted and applied, truly represents a parathyroid adenoma, never a "false-positive" scan., Summary Background Data: Although the sestamibi scan is widely ordered preoperatively to locate parathyroid adenomas, concern about a false-positive scan often causes surgeons to distrust the results. Tissues such as thyroid adenomas and lymph nodes have been blamed for false-positive studies, but the radioactivity of these presumed false-positive tissues has never been measured., Methods: Over an 1 8-month period, 17 patients were referred for persistent primary hyperparathyroidism after undergoing at least one neck exploration. All patients had a sestamibi scan prior to their initial operation that was interpreted as clearly positive and then, during or after an unsuccessful operation, deemed false-positive by the surgeon. At the authors' institution, all patients underwent repeat sestamibi scintigraphy and were taken to the operating room while radioactive for a minimally invasive radioguided parathyroidectomy (MIRP)., Results: The authors' sestamibi scans demonstrated the same single focus of radioactivity displayed on the outside scans, clearly positive. During MIRP, an adenoma was successfully located and removed in all patients, with confirmation of the diagnosis by quantitative differential radioactivity and subsequent histologic examination. Removal of the radioactive tissue cured all patients., Conclusion: Intraoperative nuclear mapping permitted identification and removal of parathyroid adenomas in all patients with positive sestamibi scans that had previously been labelled false-positive, indicating that each patient would have been cured during their previous operation if radioguided techniques were used. Surgeons should be extremely cautious in deciding intraoperatively that a positive sestamibi scan is a false-positive scan.
- Published
- 2000
- Full Text
- View/download PDF
36. The captopril renogram: a new tool for diagnosing and predicting obstruction in childhood hydronephrosis.
- Author
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Homsy YL, Tripp BM, Lambert R, Campos A, Capolicchio G, Dinh L, and Chheda H
- Subjects
- Child, Child, Preschool, Female, Humans, Hydronephrosis etiology, Infant, Male, Predictive Value of Tests, Prospective Studies, Captopril, Hydronephrosis diagnostic imaging, Kidney Pelvis, Radioisotope Renography, Ureteral Obstruction complications
- Abstract
Purpose: We evaluated the difference in response patterns of captopril versus standard renography for assessing hydronephrosis due to suspected ureteropelvic and ureterovesical junction obstruction. This technique may identify hydronephrotic kidneys in which normal function is maintained by vasoactive compensatory mechanisms. Sustained obstruction may cause these mechanisms to fail, and expose the kidneys to permanent functional deterioration in the long term., Material and Methods: We prospectively studied 15 boys and 8 girls with a mean age of 3.5 years with grades III to IV/IV hydronephrosis. Evaluations included renal sonography, standard diuretic and captopril renography, glomerular filtration rate, voiding cystography, serum creatinine, blood pressure, and urinalysis with culture and sensitivity. Obstruction was suspected at the ureteropelvic junction in 19 kidneys and at the ureterovesical junction in 9. We compared differential function values obtained by standard diuretic and captopril renography., Results: We observed certain patterns in response to captopril renography, including pattern 1--unilateral decrease in hydronephrotic kidney relative function in 5 of 23 cases, 2--bilateral decreased function in 2, 3--bilateral increased function in 4 and 4--no change in function in 12 on standard renography. When half-time was more than 20 minutes on standard diuretic renography in 8 cases, captopril renography showed an ipsilateral decrease and bilateral increase in glomerular filtration rate in 4 and 1, respectively, and no change in 3. In 12 of the 23 patients (52%) there was no difference in the results of captopril and diuretic renography as well as no change in differential function on standard diuretic renography during 1 1/2 years of observation. Surgical correction was performed in 4 patients in whom half-time was greater than 20 minutes and differential function was decreased on captopril renography., Conclusions: Our preliminary study reveals that there may be a role for captopril renography for detecting renin-angiotensin system mediated compensatory mechanisms in obstructive uropathy. When such compensatory mechanisms are activated, they may be unmasked by captopril, producing 1 of 4 patterns on renography and glomerular filtration rate. Patterns may indicate different degrees of impending renal function impairment and, thus, they may become useful for determining the progression of injury, when present, and the appropriate timing of surgical intervention.
- Published
- 1998
- Full Text
- View/download PDF
37. Minimally invasive parathyroidectomy for primary hyperparathyroidism: decreasing operative time and potential complications while improving cosmetic results.
- Author
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Norman J, Chheda H, and Farrell C
- Subjects
- Adenoma diagnostic imaging, Adenoma surgery, Humans, Hyperparathyroidism diagnostic imaging, Length of Stay, Parathyroid Neoplasms diagnostic imaging, Parathyroid Neoplasms surgery, Prospective Studies, Radionuclide Imaging, Reoperation, Technetium Tc 99m Sestamibi, Time and Motion Studies, Treatment Outcome, Hyperparathyroidism surgery, Minimally Invasive Surgical Procedures, Parathyroidectomy methods
- Abstract
Primarily because of the lack of highly accurate preoperative localizing studies, the standard operation for primary hyperparathyroidism (HPTH) has consisted of bilateral neck exploration with examination of all four parathyroid glands. Recent experience with the technetium-99m-Sestamibi scan at our hospital has suggested that this single test was now accurate enough to allow unilateral neck exploration. This study was designed to examine the efficacy and safety of minimally invasive parathyroid-ectomy in select patients with a single adenoma demonstrated on a preoperative sestamibi. Eighteen consecutive patients with primary HPTH in whom a sestamibi scan suggested a single adenoma underwent unilateral neck exploration through a 2.5-cm incision, which was extended as necessary. Results were compared to the preceding 25 parathyroid explorations for primary HPTH due to a single adenoma, which were nondirected and included bilateral neck exploration. All patients undergoing minimal exploration were found to have a single adenoma and demonstrated a normal serum calcium within 24 hours of surgery. Standard bilateral exploration failed to locate the adenoma in one patient requiring subsequent re-exploration. Operative time, incision length, and length of hospital stay were all significantly less for those undergoing minimal exploration (all P < 0.01). There were no complications in either group. Minimally invasive neck exploration is a safe and effective treatment for primary HPTH, is easily accomplished under local anesthesia, and is associated with significant reductions in operative time and hospital stay. Limited exploration provides a better cosmetic result while decreasing the potential complications of bilateral exploration, but is dependent upon a high-quality sestamibi scan.
- Published
- 1998
38. Minimally invasive parathyroidectomy facilitated by intraoperative nuclear mapping.
- Author
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Norman J and Chheda H
- Subjects
- Adenoma diagnostic imaging, Humans, Hyperparathyroidism diagnostic imaging, Parathyroid Neoplasms diagnostic imaging, Radionuclide Imaging, Adenoma surgery, Hyperparathyroidism surgery, Parathyroid Neoplasms surgery, Parathyroidectomy, Technetium Tc 99m Sestamibi
- Abstract
Background: The inability to predict the location and number of diseased parathyroid glands has precluded the wide acceptance of unilateral neck exploration for primary hyperparathyroidism. We used intraoperative nuclear mapping in patients identified by sestamibi scanning to have a single adenoma in hopes of minimizing operative intervention while maintaining the efficacy of a full exploration., Methods: Fifteen consecutive patients with primary hyperparathyroidism underwent technetium 99m-labeled sestamibi scanning 3.0 +/- 0.1 hours before operation. Placement of the initial 2.0 cm incision and all dissection were guided by quantitative gamma counting in four neck quadrants with an 11 mm Neoprobe. Ex vivo radioactivity was determined for parathyroid glands, fat, and lymph nodes. Potential radiation hazards were assessed., Results: Intraoperative nuclear mapping discriminated between 14 solitary adenomas and one patient with four-gland hyperplasia that was not predicted on preoperative sestamibi scanning. Removal of the adenoma resulted in a decline in radioactivity in that quadrant (p < 0.001) and the entire neck (p < 0.05), with equalization of all neck quadrants. Ex vivo counts always identified parathyroid tissue (p < 0.0001 versus fat and lymph node). Adenomas were located in 19 +/- 1.7 minutes through a 2.3 +/- 0.1 cm incision. No significant radiation hazard existed, and no special handling of the specimen was required (0.06 +/- 0.01 mR/hr)., Conclusions: Intraoperative nuclear mapping complements sestamibi scanning to help distinguish single-gland from multigland disease. This technique allows for a minimally invasive operation under local anesthesia in a true outpatient setting.
- Published
- 1997
- Full Text
- View/download PDF
39. Reliability of radionuclide scintigraphy for detection of testicular torsion: an animal study.
- Author
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Fischman AJ, Ahmad M, Chheda H, Peto CA, Wilkinson R, and Strauss HW
- Subjects
- Animals, Male, Radionuclide Angiography, Rats, Rats, Inbred Strains, Tissue Distribution, Sodium Pertechnetate Tc 99m, Spermatic Cord Torsion diagnostic imaging, Thallium Radioisotopes
- Abstract
Sodium pertechnetate Tc99m scintigraphy is a valuable technique for the evaluation of acute testicular torsion in postpubescent males. However, in neonates and children with small testicles, the method is less reliable. Since the testicles of adult rats and young children are of similar size, the reliability of testicular imaging for detecting torsion was evaluated in this species. The utility of the radionuclide angiogram (RA) and static images were determined in 17 anesthetized animals before, 2 h after and 20 h after ligation of the left spermatic cord. The preligation RA was asymmetric in 27% of animals, while the static images were abnormal in 18%. Postligation flow and static images were abnormal in 57% and 82% of the animals (localized to the correct side, 38% and 36%), respectively. The animals with vascular occlusion failed to show any statistically significant greater incidence of decreased radionuclide accumulation on the ligated side. To determine the influence of relative perfusion and extracellular fluid space of the scrotum and testicles on the images, additional studies were performed with 201Tl (representing perfusion) and 99mTcO4- (representing ECF space). Perfusion was approximately equal in the testis and epididymis but significantly higher in the scrotum. These results suggest that scrotal scintigraphy is unreliable for detecting acute torsion of small testicles.
- Published
- 1990
- Full Text
- View/download PDF
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