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Radhakrishnan R, Hegde SG. Acute Pancreatitis: A Red Herring in Burkitt's Lymphoma. Pancreas 2024:00006676-990000000-00133. [PMID: 38530944 DOI: 10.1097/mpa.0000000000002324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Affiliation(s)
- Remya Radhakrishnan
- Department of Paediatric Surgery, St John's Medical College, Bengaluru, India
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Hegde SG, Venkatesh P, Mathew EA, Patil M, Kumar P. An observational study on the prevalence of choledochal cyst with pancreatitis: Geographical implications and management. J Pediatr Gastroenterol Nutr 2024; 78:685-690. [PMID: 38291767 DOI: 10.1002/jpn3.12138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 12/08/2023] [Accepted: 12/18/2023] [Indexed: 02/01/2024]
Abstract
The objective of this study was to analyse the prevalence, risk factors and need for intervention in a sample of Indian children with choledochal cyst (CDC) complicated by pancreatitis with a special focus on chronic pancreatitis. A retrospective review of medical records of children admitted with CDC over 11 years was done and pancreatitis identified using INSPPIRE guidelines. Children were divided into two groups-one having choledochal cyst alone and the other choledochal cyst along with pancreatitis to determine associated risk factors. 40.2% of children with CDC had pancreatitis based on elevation of enzymes or radiological imaging. Age, total bilirubin and indirect bilirubin, requirement of intervention was significantly higher in the group with pancreatitis. 47% of those with radiological features of pancreatitis had imaging features of chronic pancreatitis. Chronic pancreatitis has not been reported previously in children with CDC and maybe peculiar to the Indian subcontinent.
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Affiliation(s)
- Shalini G Hegde
- Department of Paediatric Surgery, St. John's Medical College Hospital, Bangalore, Karnataka, India
| | - Prassanna Venkatesh
- Department of Paediatric Surgery, St. John's Medical College Hospital, Bangalore, Karnataka, India
| | | | - Mallikarjun Patil
- Department of Gastroenterology, St. John's Medical College Hospital, Bangalore, Karnataka, India
| | - Prasanna Kumar
- Department of Paediatric Surgery, St. John's Medical College Hospital, Bangalore, Karnataka, India
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Muralidharan J, Hegde SG, Ghosh S, Mondal A, Arjun MC, Thomas T, Kurpad SS, Davis C, Sachdev HS, Kurpad AV. Mandatory fortification of rice in the public distribution system in India: An ethics perspective. Indian J Med Ethics 2024; IX:26-30. [PMID: 38375654 DOI: 10.20529/ijme.2023.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2024]
Abstract
In response to the continuing high prevalence of anaemia recorded in the National Family Health Survey-5, the Indian government launched a policy for mandatory iron fortification of the rice provided through public nutrition programmes in India. This was done even though a rigorous evidence analysis had already concluded that rice fortification was not effective in preventing anaemia or iron deficiency at the population level. Fortification also poses a potential risk of iron toxicity over time, but there is no stated time period for the policy's implementation. The risk is particularly high in segments of the population who already have a high habitual iron intake, and who could be exposed to simultaneous fortification in different staples and food commodities along with the ongoing weekly Iron and Folic Acid tablets supplementation programme. Finally, this fortification policy also requires significant additional funding and resources to implement. It is crucial to examine such mandatory health actions, and to weigh the benefits and risks of harm, using the principles of public health ethics.
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Affiliation(s)
| | - Shalini G Hegde
- Department of Paediatric Surgery, St John's Medical College, Bengaluru, INDIA
| | - Santu Ghosh
- Department of Biostatistics, St John's Medical College, Bengaluru, INDIA
| | - Ankita Mondal
- Department of Biostatistics and Department of Physiology, St John's Medical College, Bengaluru, INDIA
| | - M C Arjun
- Division of Nutrition, St John's Research Institute, Bengaluru, INDIA
| | - Tinku Thomas
- Department of Biostatistics, St John's Medical College, Bengaluru, INDIA
| | - Sunita S Kurpad
- Department of Psychiatry and Department of Medical Ethics, St John's Medical College, Bengaluru, INDIA
| | - Charles Davis
- Department of Medical Ethics, St John's Medical College, Bengaluru, INDIA, and Chair for Moral Theology, University of Freiburg, GERMANY
| | | | - Anura V Kurpad
- Department of Physiology, St John's Medical College, Bengaluru, INDIA
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Hegde SG, Devi S, Pasanna RM, Padashetty C, Shubha AM, Mukhopadhyay A, Kurpad AV. Untargeted Maternal Plasma Metabolomics in Hirschsprung Disease: A Pilot Study. J Indian Assoc Pediatr Surg 2024; 29:6-12. [PMID: 38405248 PMCID: PMC10883180 DOI: 10.4103/jiaps.jiaps_134_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 09/11/2023] [Accepted: 09/28/2023] [Indexed: 02/27/2024] Open
Abstract
Background and Aims Hirschsprung disease (HSCR) is a congenital disorder of unknown etiology affecting the enteric nervous system (ENS). Since the early gestational development of the ENS is dependent on the prenatal maternal metabolic environment, the objective of this pilot study was to explore the role of specific maternal plasma metabolites in the etiology of HSCR. Methods In this cross-sectional study, postnatal (as a surrogate for prenatal) plasma samples were obtained from mothers of children diagnosed with HSCR (n = 7) and age-matched mothers of normal children (n = 6). The plasma metabolome was analyzed by ultra-high-pressure liquid chromatography and mass spectrometry. Metabolites were identified by mzCloud using Compound Discoverer software. Using an untargeted metabolomics workflow, metabolites with case versus control group differences were identified. Results A total of 268 unique plasma metabolites were identified and annotated in maternal plasma. Of these, 57 were significantly different between case and control groups (P < 0.05, t-test). Using a false discovery rate corrected cutoff of 10% to adjust for multiple comparisons, 19 metabolites were significantly different in HSCR cases, including carnitines, medium-chain fatty acids, and glutamic acid. Pathways affected were for amino acid and lipid metabolism. Conclusion Disordered prenatal metabolic pathways may be involved in the etiopathogenesis of HSCR in the developing fetus. This is the first study to assess maternal plasma metabolomics in HSCR.
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Affiliation(s)
- Shalini G Hegde
- Department of Paediatric Surgery, Bengaluru, Karnataka, India
| | - Sarita Devi
- Department of Paediatric Surgery, Bengaluru, Karnataka, India
| | | | | | | | | | - Anura V Kurpad
- Department of Division of Nutrition, St. John's Research Institute, Bengaluru, Karnataka, India
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Kurpad AV, Pasanna RM, Hegde SG, Patil M, Mukhopadhyay A, Sachdev HS, Bhat KG, Sivadas A, Devi S. Bioavailability and daily requirement of vitamin B 12 in adult humans: an observational study of its colonic absorption and daily excretion as measured by [ 13C]-cyanocobalamin kinetics. Am J Clin Nutr 2023; 118:1214-1223. [PMID: 38044024 DOI: 10.1016/j.ajcnut.2023.08.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 08/28/2023] [Accepted: 08/30/2023] [Indexed: 12/05/2023] Open
Abstract
BACKGROUND Clinical and biochemical vitamin B12 (B12) deficiency is lower than anticipated in vegetarians. Extraileal absorption, such as from the colon, as well as reduced daily excretion, may be adaptive mechanisms to maintain B12 homeostasis with marginal intakes. OBJECTIVE To measure the absorption of B12 from the small and large intestine, and its daily rate of excretion from the body, using a [13C]-cyanocobalamin tracer. METHODS Oral B12 bioavailability was measured over 12 h after administration of [13C]-cyanocobalamin tracer (2.5 μg) in normal participants. The colonic B12 bioavailability was evaluated by direct instillation of [13C]-cyanocobalamin (5 μg) into the ascending colon. Bioavailability was calculated from 2-compartmental modeling of the tracer appearance in plasma. The excretion rate of B12 was measured from [13C]-cyanocobalamin elimination from the body over 4 wk after oral dosing (5 μg). RESULTS The oral B12 bioavailability (n = 11) was 63% ± 10% measured over 12 h. A late absorption peak, accounting for 12% of the absorption, was observed after an average lag time of 8.7 h from dosing. The colonic B12 bioavailability (n = 10) was 7% ± 5% over 4 h. The daily B12 excretion rate (n = 4) was 0.7 ± 0.2 μg/d. The minimum daily requirement of B12 in these participants was derived at 1 μg /d. CONCLUSIONS B12 is absorbed in the human colon. This observation confirms the potential contribution of the colon in daily B12 nutriture, and along with a possible lower requirement, could explain the absence of clinical deficiency in populations with marginal B12 intakes. TRIAL REGISTRATION NUMBER This study was registered in Clinical Trials Registry of India (CTRI) with the registration number CTRI/2018/04/012957, available from https://ctri.nic.in/Clinicaltrials/showallp.php?mid1=49319&EncHid=&userName=029108.
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Affiliation(s)
- Anura V Kurpad
- Department of Physiology, St. John's Medical College, Bengaluru, India.
| | - Roshni M Pasanna
- Division of Nutrition, St. John's Research Institute, Bengaluru, India
| | - Shalini G Hegde
- Department of Paediatric Surgery, St. John's Medical College, Bengaluru, India
| | - Mallikarjun Patil
- Department of Gastroenterology, St. John's Medical College, Bengaluru, India
| | | | - Harshpal S Sachdev
- Department of Paediatrics, Sitaram Bhartia Institute of Science and Research, New Delhi, India
| | - Kishor G Bhat
- Division of Nutrition, St. John's Research Institute, Bengaluru, India
| | - Ambily Sivadas
- Division of Nutrition, St. John's Research Institute, Bengaluru, India
| | - Sarita Devi
- Division of Nutrition, St. John's Research Institute, Bengaluru, India.
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Hegde SG, Kashyap S, Devi S, Kumar P, Michael Raj A J, Kurpad AV. Estimation of exocrine pancreatic insufficiency in children with acute pancreatitis using the 13C mixed triglyceride breath test. Pancreatology 2023; 23:601-606. [PMID: 37481340 DOI: 10.1016/j.pan.2023.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 07/10/2023] [Accepted: 07/16/2023] [Indexed: 07/24/2023]
Abstract
BACKGROUND /Objective: The extent of exocrine pancreatic insufficiency (EPI) in the paediatric population with acute pancreatitis (AP) is unknown. The primary objective was to use a 6 h stable-isotope breath test to determine the prevalence of EPI in children with AP. The secondary objective was to determine the diagnostic ability of a 4 h abbreviated breath test in the detection of EPI. METHODS 13C-mixed triglyceride (MTG) breath test was used to measure fat digestibility in 12 children with AP and 12 normal children. EPI was diagnosed based on a cumulative dose percentage recovery (cPDR) cut-off value < 26.8% present in literature. To reduce the test burden, the diagnostic accuracy of an abbreviated 4 h test was evaluated, using a cPDR cut-off that was the 2.5th percentile of its distribution in control children. RESULTS The cPDR of cases was significantly lower than that of controls (27.71 ± 7.88% vs 36.37 ± 4.70%, p = 0.005). The cPDR during acute illness was not significantly different to that at 1 month follow up (24.69 ± 6.83% vs 26.98 ± 11.10%, p = 0.52). The 4 h and 6 h breath test results correlated strongly (r = 0.93, p < 0.001) with each other. The new 4 h test had 87.5% sensitivity and 93.8% specificity for detecting EPI. CONCLUSION Two-thirds (66.7%) of this sample of children with AP had EPI during admission, which persisted at 1 month follow up. The 4 h abbreviated 13C-MTG breath test has good diagnostic ability to detect EPI in children and may improve its clinical utility in this age group.
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Affiliation(s)
- Shalini G Hegde
- Department of Paediatric Surgery, St. John's Medical College Hospital, India
| | - Sindhu Kashyap
- Division of Nutrition, St. John's Research Institute, Bangalore, India
| | - Sarita Devi
- Division of Nutrition, St. John's Research Institute, Bangalore, India
| | - Prasanna Kumar
- Department of Paediatric Surgery, St. John's Medical College Hospital, India
| | | | - Anura V Kurpad
- Department of Physiology, St. John's Medical College Hospital, India.
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Hegde SG, Devi S, Sivadas A, Shubha AM, Thomas A, Mukhopadhyay A, Kurpad AV. Maternal Vitamin A Status as a Risk Factor of Hirschsprung Disease in the Child. Clin Transl Gastroenterol 2023; 14:e00619. [PMID: 37490568 PMCID: PMC10522106 DOI: 10.14309/ctg.0000000000000619] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 06/14/2023] [Indexed: 07/27/2023] Open
Abstract
INTRODUCTION The gene-environment interaction of the REarranged during Transfection ( RET ) gene with vitamin A in the etiopathogenesis of Hirschsprung disease (HSCR) has been suggested in rodents. The aim of this study was to evaluate vitamin A status in mothers of children with HSCR and to assess its association with pathogenic variants of the RET gene in affected children. METHODS This was a case-control study of stable isotope-based vitamin A measurement stores of mothers of children diagnosed with HSCR (within 8 months from birth, n = 7) and age-matched mothers of normal children (n = 6). Next-generation sequencing of RET exons, along with their upstream promoter region, was performed in the 7 HSCR proband-parent triads to evaluate pathogenic variants. RESULTS Maternal vitamin A stores in the HSCR group was almost 50% that of those in controls, tending toward significance (0.50 ± 0.17 vs 0.89 ± 0.51 μmol/g respectively, P = 0.079). Two novel pathogenic de novo mutations were identified in 2 cases, and a rare single-nucleotide deletion was detected in the 3.5-kb RET upstream region, in a heterozygous state, in all 7 proband-parent triads. Low-penetrance RET haplotypes associated with HSCR were detected in 5 cases. DISCUSSION Mothers with children with HSCR had lower vitamin A liver stores than mothers with normal children, and the children who were affected had HSCR despite having no established pathogenic RET variants. Lower maternal vitamin A status may increase the penetrance of genetic mutations in RET , and vitamin-A mediated gene-environment interactions may underpin some of the etiology of HSCR.
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Affiliation(s)
- Shalini G. Hegde
- Department of Paediatric Surgery, St. John's Medical College Hospital, Bangalore, India
| | - Sarita Devi
- Division of Nutrition, St. John's Research Institute, Bangalore, India
| | - Ambily Sivadas
- Division of Nutrition, St. John's Research Institute, Bangalore, India
| | | | - Annamma Thomas
- Department of Obstetrics and Gynaecology, St. John's Medical College Hospital, Bangalore, India
| | | | - Anura V. Kurpad
- Department of Physiology, St. John's Medical College Hospital, Bangalore, India
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Hegde SG, Dhareshwar S, Bandyopadhyay S, Kuriyan RR, Idiculla J, Ghosh S, Kurpad AV, Shivakumar N. Central obesity in low BMI as a risk factor for COVID-19 severity in South Indians. Asia Pac J Clin Nutr 2022; 31:142-146. [PMID: 35357112 PMCID: PMC7612990 DOI: 10.6133/apjcn.202203_31(1).0015] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND OBJECTIVES South Asians are known to have excess adiposity at a lower body mass index, with truncal fat accumulation. Whether this confers higher risk to develop severe COVID-19 is not known. This study evaluated body mass index, body fat mass and waist circumference as risk factors for COVID-19 severity and its progression, in South Asian adults. METHODS AND STUDY DESIGN Details of COVID-19 patients (19-90 years) were obtained prospectively, along with weight, height, waist circumference and body fat mass assessed by bioelectrical impedance analysis. Binomial logistic and Poisson regression were performed to test associations between waist circumference, body fat mass and body mass index to evaluate the adjusted OR or relative risk for disease severity at admission and length of stay. RESULTS After adjusting for age, sex, height and co-morbidities, body mass index >23 kg/m2 (adjusted OR 2.758, 95% CI 1.025, 7.427), waist circumference (adjusted OR 1.047, 95% CI 1.002, 1.093) and body fat mass (adjusted OR 1.111, 95% CI 1.013, 1.219) were associated with a significant risk for disease severity at admission, while only waist circumference (adjusted relative risk 1.004, 95% CI 1.001, 1.008), and body fat mass (adjusted relative risk 1.011, 95% CI 1.003, 1.018), were associated with a significantly longer length of stay. CONCLUSIONS Body mass index, at a lower cut-off of >23 kg/m2, is a significant risk factor for COVID-19 disease severity in the group of patients studied. The waist circumference and body fat mass are also good indicators for both severity at admission and length of stay.
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Affiliation(s)
- Shalini G Hegde
- Department of Paediatric Surgery, St. John's Medical College Hospital, India
- Division of Nutrition, St. John's Research Institute, Bengaluru, India
| | - Shashank Dhareshwar
- Department of Nephrology, St. John's Medical College Hospital Bengaluru, India
| | | | - Rebecca R Kuriyan
- Division of Nutrition, St. John's Research Institute, Bengaluru, India
| | - Jyothi Idiculla
- Department of Medicine, St. John's Medical College Hospital, Bengaluru, India
| | - Santu Ghosh
- Department of Biostatistics, St. John's Medical College, Bengaluru, India
| | - Anura V Kurpad
- Division of Nutrition, St. John's Research Institute, Bengaluru, India
- Department of Physiology, St. John's Medical College, Bengaluru, India
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Snow AA, Culley TM, Campbell LG, Sweeney PM, Hegde SG, Ellstrand NC. Long-term persistence of crop alleles in weedy populations of wild radish (Raphanus raphanistrum). New Phytol 2010; 186:537-548. [PMID: 20122132 DOI: 10.1111/j.1469-8137.2009.03172.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
*Hybridization allows transgenes and other crop alleles to spread to wild/weedy populations of related taxa. Researchers have debated whether such alleles will persist because low hybrid fitness and linkage to domestication traits could severely impede introgression. *To examine variation in the fates of three unlinked crop alleles, we monitored four experimental, self-seeding, hybrid populations of Raphanus raphanistrum x Raphanus sativus (radish) in Michigan, USA, over a decade. We also compared the fecundity of advanced-generation hybrid plants with wild plants in a common garden experiment. *Initially, F(1) hybrids had reduced fitness, but the populations quickly evolved wild-type pollen fertility. In Year 10, the fecundity of plants from the experimental populations was similar to that of wild genotypes. Crop-specific alleles at the three loci persisted for 10 yr in all populations, and their frequencies varied among loci, populations and years. *This research provides a unique case study of substantial variation in the rates and patterns of crop allele introgression after a single hybridization event. Our findings demonstrate that certain crop alleles can introgress easily while others remain rare, supporting the assumption that neutral or beneficial transgenes that are not linked to maladaptive traits can persist in the wild.
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Affiliation(s)
- A A Snow
- Department of Evolution, Ecology, and Organismal Biology, Ohio State University, Columbus, OH 43210, USA.
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Ravikumar RL, Patil BS, Soregaon CD, Hegde SG. Genetic evidence for gametophytic selection of wilt resistant alleles in chickpea. Theor Appl Genet 2007; 114:619-25. [PMID: 17143648 DOI: 10.1007/s00122-006-0462-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2006] [Accepted: 11/11/2006] [Indexed: 05/08/2023]
Abstract
Gametophytic selection can drastically reduce the number of selection cycles during crop improvement programs. The objective of the present investigation was to test whether the nature of inheritance of two unlinked disease-resistant loci, h(1) and h(2), against Fusarium wilt in chickpea (Cicer arietinum L.) under gametophytic (pollen) selection was similar to that already observed at sporophytic level. A homozygous dominant (H(1)H(1)H(2)H(2)) susceptible genotype JG-62 was crossed to a recessive (h(1)h(1)h(2)h(2)) resistant genotype WR-315 to produce 20 F(1) hybrid seeds. In the following generation, flower buds of 10 F(1) hybrid plants were subjected to toxin stress before anthesis and the remaining ten control F(1) plants' flowers were sprayed with water. Thirty-four selected BC(1) plants were generated by test crossing resistant WR-315 individuals with pollen from toxin-stressed F(1) individuals. Both control and treated F(1) plants were selfed to produce respective F(2) generations. Two DNA markers, CS-27(700bp) and A07C(430bp), linked to susceptible alleles H(1) and H(2), respectively, were used to study the inheritance patterns of h(1) and h(2) loci in the F(2) and BC(1) generations. One hundred and forty-four selected F(2), 129 control F(2), and 34 selected backcross individuals were tested for the presence or absence of DNA markers. Except for the control F(2), observed ratios of selected F(2) and BC(1) populations exhibited significant chi-square deviations from expected monogenic and digenic ratios. Our results suggest that gametophytic selection is as effective as that realized at the sporophytic level, and that the gametophytic selection can be an effective breeding tool for plant breeding programs.
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Affiliation(s)
- R L Ravikumar
- Department of Genetics and Plant Breeding, University of Agricultural Sciences, Dharwad 580005, India.
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Devassy BM, Halligudi SB, Hegde SG, Halgeri AB, Lefebvre F. 12-Tungstophosphoric acid/zirconia--a highly active stable solid acid--comparison with a tungstated zirconia catalyst. Chem Commun (Camb) 2002:1074-5. [PMID: 12122671 DOI: 10.1039/b200722c] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A highly active and stable zirconia supported 12-tungstophosphoric acid catalyst is found to be 2-3 times more active in benzylation and acylation reactions than a tungstated zirconia catalyst.
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Affiliation(s)
- Biju M Devassy
- Inorganic Chemistry & Catalysis Division, National Chemical Laboratory, Pune-411 008, India
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12
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Hegde SG, Ellstrand NC. Life History Differences between Rare and Common Flowering Plant Species of California and the British Isles. Int J Plant Sci 1999; 160:1083-1091. [PMID: 10568775 DOI: 10.1086/314204] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Generalizations about rare and endangered species are important for the development of conservation management policy and for understanding of the nature of rarity. Therefore, we sought such generalizations by statistically comparing eight life history and reproductive traits of rare and common plant species in two better-studied but climatically and geographically distinct Holarctic floras-those of California and the British Isles. Trends were often similar in both floras. Rare and common species differ significantly for a number of characters. In both floras, a woody habit was significantly more frequent for the rare species than the common species. Also, in both floras, monocarpy was less frequent in the rare species, significantly so in California. The rare species of both floras were, on average, significantly shorter in stature than the common species. This trend in stature remained significant when nonwoody species were compared but did not do so for woody species. Rare and common species differed with regard to their frequency of inflorescence structure types, but these differences were not concordant for both floras. The rare species of the British Isles had significantly higher proportions of mixed and polymorphic flower colors; the trend was not significant in California. In both floras, rare species had a higher frequency of many-seeded fruits, significantly so in California. California's rare species had a significantly higher frequency of dehiscent fruits than common species; the trend was reversed and not significant for the British Isles. We found no significant differences for characters associated with fruit dispersal. Finally, in California, the median altitude of the range of the common species was significantly greater than that of the rare species. At present, these correlates cannot be assigned as possible causes or consequences of rarity. Nonetheless, they may represent "high-risk" traits that could be used to identify other species already at risk or potentially at risk of becoming rarer.
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Schweitzer BA, Loida PJ, Thompson-Mize RL, CaJacob CA, Hegde SG. Design and synthesis of beta-carboxamido phosphonates as potent inhibitors of imidazole glycerol phosphate dehydratase. Bioorg Med Chem Lett 1999; 9:2053-8. [PMID: 10450980 DOI: 10.1016/s0960-894x(99)00338-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We describe the synthesis and enzymatic activity of a library of beta-carboxamido phosphonates as inhibitors of imidazole glycerol phosphate dehydratase (IGPD). Biological results suggest the presence of an enzymatic interaction site not previously observed for other inhibitors of IGPD.
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Abstract
In Pongamia pinnata only one of the two ovules develops into a seed in most of the pods. Since pollen was not found to be limiting and reduced fertilization could not completely explain the observed frequency of seed abortion, it implied an effect of postfertilization factors. Aqueous extracts of developing seeds and maternal tissue (placenta) did not influence abortion in vitro, suggesting that abortion may not be mediated by a chemical. Experimental uptake of (14)C sucrose in vitro indicated that both the stigmatic and the peduncular seed have similar inherent capacities of drawing resources, but the peduncular seed is deprived of resources in the presence of the stigmatic seed. This deprivation of the peduncular seed could be offset by supplying an excess of hormones leading to the subsequent formation of two seeds in a pod. The prevalence of single-seeded pods in P. pinnata seems therefore to be a result of competition between the two seeds for maternal resources. The evolutionary significance of single-seeded pods in P. pinnata is discussed with respect to possible dispersal advantage enjoyed by such pods.
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Affiliation(s)
- H S Arathi
- Department of Genetics and Plant Breeding, University of Agricultural Sciences, G.K.V.K., Bangalore 560 065, India; and
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