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King MR, Ruff KM, Lin AZ, Pant A, Farag M, Lalmansingh JM, Wu T, Fossat MJ, Ouyang W, Lew MD, Lundberg E, Vahey MD, Pappu RV. Macromolecular condensation organizes nucleolar sub-phases to set up a pH gradient. Cell 2024; 187:1889-1906.e24. [PMID: 38503281 DOI: 10.1016/j.cell.2024.02.029] [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] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 01/02/2024] [Accepted: 02/22/2024] [Indexed: 03/21/2024]
Abstract
Nucleoli are multicomponent condensates defined by coexisting sub-phases. We identified distinct intrinsically disordered regions (IDRs), including acidic (D/E) tracts and K-blocks interspersed by E-rich regions, as defining features of nucleolar proteins. We show that the localization preferences of nucleolar proteins are determined by their IDRs and the types of RNA or DNA binding domains they encompass. In vitro reconstitutions and studies in cells showed how condensation, which combines binding and complex coacervation of nucleolar components, contributes to nucleolar organization. D/E tracts of nucleolar proteins contribute to lowering the pH of co-condensates formed with nucleolar RNAs in vitro. In cells, this sets up a pH gradient between nucleoli and the nucleoplasm. By contrast, juxta-nucleolar bodies, which have different macromolecular compositions, featuring protein IDRs with very different charge profiles, have pH values that are equivalent to or higher than the nucleoplasm. Our findings show that distinct compositional specificities generate distinct physicochemical properties for condensates.
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Affiliation(s)
- Matthew R King
- Department of Biomedical Engineering, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA; Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Kiersten M Ruff
- Department of Biomedical Engineering, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA; Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Andrew Z Lin
- Department of Biomedical Engineering, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA; Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Avnika Pant
- Department of Biomedical Engineering, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA; Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Mina Farag
- Department of Biomedical Engineering, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA; Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Jared M Lalmansingh
- Department of Biomedical Engineering, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA; Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Tingting Wu
- Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA; Department of Electrical and Systems Engineering, James F. McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Martin J Fossat
- Department of Biomedical Engineering, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA; Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Wei Ouyang
- Department of Bioengineering, Schools of Engineering and Medicine, Stanford University, Stanford, CA, USA; Department of Pathology, School of Medicine, Stanford University, Stanford, CA, USA; Science for Life Laboratory, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Matthew D Lew
- Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA; Department of Electrical and Systems Engineering, James F. McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Emma Lundberg
- Department of Bioengineering, Schools of Engineering and Medicine, Stanford University, Stanford, CA, USA; Department of Pathology, School of Medicine, Stanford University, Stanford, CA, USA; Science for Life Laboratory, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Michael D Vahey
- Department of Biomedical Engineering, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA; Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Rohit V Pappu
- Department of Biomedical Engineering, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA; Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA.
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Saha D, Vishwakarma S, Gupta RK, Pant A, Dhyani V, Sharma S, Majumdar S, Kaur I, Giri L. Non-prophylactic resveratrol-mediated protection of neurite integrity under chronic hypoxia is associated with reduction of Cav1.2 channel expression and calcium overloading. Neurochem Int 2023; 164:105466. [PMID: 36587745 DOI: 10.1016/j.neuint.2022.105466] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 12/17/2022] [Accepted: 12/19/2022] [Indexed: 12/31/2022]
Abstract
Cellular hypoxia is a major cause of oxidative stress, culminating in neuronal damage in neurodegenerative diseases. Numerous ex vivo studies have implicated that hypoxia episodes leading to disruption of Ca2+ homeostasis and redox status contribute to the progression of various neuropathologies and cell death. Isolation and maintenance of primary cell culture being cost-intensive, the details of the time course relationship between Ca2+ overload, L-type Ca2+ channel function, and neurite retraction under chronic and long-term hypoxia remain undefined. In order to explore the effect of oxidative stress and Ca2+ overload on neurite length, first, we developed a 5-day-long neurite outgrowth model using N2a cell line. Second, we propose a chronic hypoxia model to investigate the modulation of the L-type Ca2+ channel (Cav1.2) and oxidative resistance gene (OXR1) expression level during the process of neurite retraction and neuronal damage over 32 h. Thirdly, we developed a framework for quantitative analysis of cytosolic Ca2+, superoxide formation, neurite length, and constriction formation in individual cells using live imaging that provides an understanding of molecular targets. Our findings suggest that an increase in cytosolic Ca2+ is a feature of an early phase of hypoxic stress. Further, we demonstrate that augmentation in the L-type channel leads to amplification in Ca2+ overload, ROS accumulation, and a reduction in neurite length during the late phase of hypoxic stress. Next, we demonstrated that non-prophylactic treatment of resveratrol leads to the reduction of calcium overloading under chronic hypoxia via lowering of L-type channel expression. Finally, we demonstrate that resveratrol-mediated reduction of Cav1.2 channel and STAT3 expression are associated with retention of neurite integrity. The proposed in vitro model assumes significance in the context of drug designing and testing that demands monitoring of neurite length and constriction formations by imaging before animal testing.
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Affiliation(s)
- Debasmita Saha
- Department of Chemical Engineering, Indian Institute of Technology, Hyderabad, India
| | - Sushma Vishwakarma
- Brien Holden Eye Research Centre, LV Prasad Eye Institute, Hyderabad, India
| | - Rishikesh Kumar Gupta
- International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland; Postgraduate School of Molecular Medicine, Medical University of Warsaw, Warsaw, Poland
| | - Avnika Pant
- Department of Chemical Engineering, Indian Institute of Technology, Hyderabad, India
| | - Vaibhav Dhyani
- Department of Chemical Engineering, Indian Institute of Technology, Hyderabad, India; Optical Science Centre, Faculty of Science Engineering and Technology, Swinburne University of Technology, Melbourne, Australia
| | - Sarmeela Sharma
- Brien Holden Eye Research Centre, LV Prasad Eye Institute, Hyderabad, India
| | - Saptarshi Majumdar
- Department of Chemical Engineering, Indian Institute of Technology, Hyderabad, India
| | - Inderjeet Kaur
- Brien Holden Eye Research Centre, LV Prasad Eye Institute, Hyderabad, India
| | - Lopamudra Giri
- Department of Chemical Engineering, Indian Institute of Technology, Hyderabad, India.
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Bishnoi S, Huda N, Islam S, Pant A, Agarwal S, Dholariya R. Association between Psychological Status and Functional Outcome in Surgically Managed Fractures around Hip in Geriatric Patients - A Prospective Study. Malays Orthop J 2021; 15:18-25. [PMID: 34429818 PMCID: PMC8381662 DOI: 10.5704/moj.2107.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 02/23/2021] [Indexed: 11/06/2022] Open
Abstract
Introduction: Fractures around the hip in the geriatric population not only lead to functional but also psychological impairment. Psychiatric disturbances can be associated with poor participation in rehabilitation, increased risk of falling again, and higher rates of mortality. The present study was undertaken to assess the association between the psychological status and functional outcome of surgically managed elderly Indian patients who had sustained fractures around the hip. Material and Methods: The present study was a hospital based prospective, single centre study. One hundred and two geriatric patients who had sustained hip fracture and had been managed surgically, having no cognitive dysfunction, living independently, having unhindered walking capability before the fracture, were included in the study. They were called for follow-up at 3rd, 6th, and 12th month after the hip surgery. Psychological assessment was done by the Hospital Anxiety and Depression Scale (HADS) and functional outcome by using the Harris hip score (HHS). Results: Our study did not show association between psychological status and functional outcome except in one sub-group. Significant correlation was observed between the psychological status and functional outcome in most of the patients in the extra-capsular group. We have identified improvement in the depression, anxiety and functional scores during the follow-up. Conclusion: We conclude that psychiatric disturbances in a geriatric patient after undergoing a surgery for hip fracture may lead to poor recovery. We recommend that all such geriatric patients should undergo a psychological assessment and proper therapy should be instituted to achieve good functional recovery.
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Affiliation(s)
- S Bishnoi
- Department of Orthopaedics, Teerthanker Mahaveer University Medical College and Research Centre, Moradabad, India
| | - N Huda
- Department of Orthopaedics, Teerthanker Mahaveer University Medical College and Research Centre, Moradabad, India
| | - Smu Islam
- Department of Orthopaedics, Teerthanker Mahaveer University Medical College and Research Centre, Moradabad, India
| | - A Pant
- Department of Orthopaedics, Teerthanker Mahaveer University Medical College and Research Centre, Moradabad, India
| | - S Agarwal
- Department of Orthopaedics, Teerthanker Mahaveer University Medical College and Research Centre, Moradabad, India
| | - R Dholariya
- Department of Orthopaedics, Teerthanker Mahaveer University Medical College and Research Centre, Moradabad, India
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Huda N, Kumar H, Pant A, Awasthi S, Bishnoi S, Islam M. Role of triple injection of Platelet rich plasma as a therapeutic strategy for Osteoarthritis knee: A single blind prospective, hospital based study. Cytotherapy 2020. [DOI: 10.1016/j.jcyt.2020.03.362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Poole LG, Pant A, Baker KS, Kopec AK, Cline-Fedewa HM, Iismaa SE, Flick MJ, Luyendyk JP. Chronic liver injury drives non-traditional intrahepatic fibrin(ogen) crosslinking via tissue transglutaminase. J Thromb Haemost 2019; 17:113-125. [PMID: 30415489 PMCID: PMC6322974 DOI: 10.1111/jth.14330] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Indexed: 12/25/2022]
Abstract
Essentials Fibrin clots are often implicated in the progression of liver fibrosis. Liver fibrosis was induced in transgenic mice with defects in clot formation or stabilization. Liver fibrosis and fibrin(ogen) deposition do not require fibrin polymerization or factor XIIIa. Fibrin(ogen) is an in vivo substrate of tissue transglutaminase in experimental liver fibrosis. SUMMARY: Background Intravascular fibrin clots and extravascular fibrin deposits are often implicated in the progression of liver fibrosis. However, evidence supporting a pathological role of fibrin in hepatic fibrosis is indirect and based largely on studies using anticoagulant drugs that inhibit activation of the coagulation protease thrombin, which has other downstream targets that promote fibrosis. Therefore, the goal of this study was to determine the precise role of fibrin deposits in experimental hepatic fibrosis. Methods Liver fibrosis was induced in mice expressing mutant fibrinogen insensitive to thrombin-mediated proteolysis (i.e. locked in the monomeric form), termed FibAEK mice, and factor XIII A2 subunit-deficient (FXIII-/- ) mice. Female wild-type mice, FXIII-/- mice and homozygous FibAEK mice were challenged with carbon tetrachloride (CCl4 ) twice weekly for 4 weeks or 6 weeks (1 mL kg-1 , intraperitoneal). Results Hepatic injury and fibrosis induced by CCl4 challenge were unaffected by FXIII deficiency or inhibition of thrombin-catalyzed fibrin polymer formation (in FibAEK mice). Surprisingly, hepatic deposition of crosslinked fibrin(ogen) was not reduced in CCl4 -challenged FXIII-/- mice or FibAEK mice as compared with wild-type mice. Rather, deposition of crosslinked hepatic fibrin(ogen) following CCl4 challenge was dramatically reduced in tissue transglutaminase-2 (TGM2)-deficient (TGM2-/- ) mice. However, the reduction in crosslinked fibrin(ogen) in TGM2-/- mice did not affect CCl4 -induced liver fibrosis. Conclusions These results indicate that neither traditional fibrin clots, formed by the thrombin-activated FXIII pathway nor atypical TGM2-crosslinked fibrin(ogen) contribute to experimental CCl4 -induced liver fibrosis. Collectively, the results indicate that liver fibrosis occurs independently of intrahepatic fibrin(ogen) deposition.
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Affiliation(s)
- L G Poole
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI, USA
| | - A Pant
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI, USA
| | - K S Baker
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - A K Kopec
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI, USA
| | - H M Cline-Fedewa
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI, USA
| | - S E Iismaa
- Division of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
| | - M J Flick
- Cancer and Blood Diseases Institute, Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - J P Luyendyk
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI, USA
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
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Pant A, Kumar R, Wani NA, Verma S, Sharma R, Pande V, Saxena AK, Dixit R, Rai R, Pandey KC. Allosteric Site Inhibitor Disrupting Auto-Processing of Malarial Cysteine Proteases. Sci Rep 2018; 8:16193. [PMID: 30385827 PMCID: PMC6212536 DOI: 10.1038/s41598-018-34564-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 10/16/2018] [Indexed: 02/08/2023] Open
Abstract
Falcipains are major haemoglobinases of Plasmodium falciparum required for parasite growth and development. They consist of pro- and mature domains that interact via 'hot-spot' interactions and maintain the structural integrity of enzyme in zymogen state. Upon sensing the acidic environment, these interactions dissociate and active enzyme is released. For inhibiting falcipains, several active site inhibitors exist, however, compounds that target via allosteric mechanism remains uncharacterized. Therefore, we designed and synthesized six azapeptide compounds, among which, NA-01 & NA-03 arrested parasite growth by specifically blocking the auto-processing of falcipains. Inhibitors showed high affinity for enzymes in presence of the prodomain without affecting the secondary structure. Binding of NA-03 at the interface induced rigidity in the prodomain preventing structural reorganization. We further reported a histidine-dependent activation of falcipain. Collectively, for the first time we provide a framework for blocking the allosteric site of crucial haemoglobinases of the human malaria parasite. Targeting the allosteric site could provide high selectivity and less vulnerable to drug resistance.
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Affiliation(s)
- A Pant
- ICMR-National Institute of Malaria Research, Dwarka Sector 8, New Delhi, India
- Department of Biotechnology, Kumaun University, Nainital, Uttarakhand, India
| | - R Kumar
- Integrated Science Lab, Umeå University, Umeå, Sweden
| | - N A Wani
- Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Jammu, India
| | - S Verma
- ICMR-National Institute of Malaria Research, Dwarka Sector 8, New Delhi, India
- Department of Biotechnology, Kumaun University, Nainital, Uttarakhand, India
| | - R Sharma
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - V Pande
- Department of Biotechnology, Kumaun University, Nainital, Uttarakhand, India
| | - A K Saxena
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - R Dixit
- ICMR-National Institute of Malaria Research, Dwarka Sector 8, New Delhi, India
| | - R Rai
- Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Jammu, India
| | - K C Pandey
- ICMR-National Institute of Malaria Research, Dwarka Sector 8, New Delhi, India.
- Department of Biochemistry, ICMR-National Institute for Research in Environmental Health, Bhopal, MP - 462001, India.
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Pant A, Pasupureddy R, Pande V, Seshadri S, Dixit R, Pandey KC. Proteases in Mosquito Borne Diseases: New Avenues in Drug Development. Curr Top Med Chem 2017; 17:2221-2232. [PMID: 28137230 DOI: 10.2174/1568026617666170130122231] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 09/12/2016] [Accepted: 10/27/2016] [Indexed: 02/08/2023]
Abstract
INTRODUCTION Mosquito borne diseases continue to propagate and cause millions of deaths annually. They are caused either by protozoan parasites such as Plasmodium, Toxoplasma or by flaviviruses including Dengue and Zika. Among the proteome of such parasitic organisms, proteases play essential roles in events such as host invasion, hemoglobin hydrolysis, replication and immune evasion. Plasmepsin V (PMV), an endoplasmic reticulum resident aspartic protease of Plasmodium spp., is involved in the export of ~400 proteins containing the conserved Plasmodium Export Element motif (PEXEL). Interactions and cleavage of PEXEL proteins by PM V is necessary for export to and across the parasitophorous vacuole membrane. Protease System: Similarly in flaviviruses, a two-component protease system consisting of nonstructural proteins, NS2B and NS3, interacts with other non-structural proteins and plays a major role in viral replication, polyprotein cleavage and virion particle assembly. Thus, proteases involved in indispensable roles in pathogen machinery can be considered as attractive drug targets. Inhibitors against proteases are being used in clinical trials for other communicable and non-communicable diseases. Currently, hydroxyethylamine based inhibitors targeting the catalytic site of PM V with picomolar inhibitory concentrations have been tested in vitro. CONCLUSION For recently characterized disease such as Zika, no known treatments exist while compound such as Policresulen has high affinity for Dengue NS2B/NS3 complex. Understanding proteases structure-function relationship and protease-inhibitor interactions can provide new insights for novel chemotherapeutic strategies.
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Affiliation(s)
- A Pant
- National Institute of Malaria Research, Dwarka Sector - 8, New Delhi - 110077, India,Department of Biotechnology, Kumaun University, Nainital, Uttarakhand – 263001, India
| | - R Pasupureddy
- National Institute of Malaria Research, Dwarka Sector - 8, New Delhi - 110077, India,Institute of Science, Nirma University, SG Highway, Ahmedabad, Gujarat - 382481, India
| | - V Pande
- Department of Biotechnology, Kumaun University, Nainital, Uttarakhand – 263001, India
| | - S Seshadri
- Institute of Science, Nirma University, SG Highway, Ahmedabad, Gujarat - 382481, India
| | - R Dixit
- National Institute of Malaria Research, Dwarka Sector - 8, New Delhi - 110077, India
| | - K C Pandey
- Department of Biochemistry, National Institute for Research in Environmental Health, Bhopal, MP - 462001, India
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Shrestha R, Shrestha B, Shakya Shrestha S, Pant A, Prajapati B, Karmacharya B. Study of Pre-disposing Factors of Acute Exacerbation of Chronic Obstructive Pulmonary Disease and Antibiotic Prescribing Pattern with Reference to Antibiotic Sensitivity Test. ACTA ACUST UNITED AC 2017; 13:250-5. [DOI: 10.3126/kumj.v13i3.16817] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Background Chronic Obstructive Pulmonary Disease (COPD) affects about 329 million people worldwide, which is nearly 5% of the entire global population. In the context of Nepal, COPD accounts for 43% of the non-communicable disease burden and 2.56% of hospitalizations. Various pre-disposing factors like bacterial, viral, fungal, smoking, occupational exposures and genetic factors have been proposed to precipitate COPD and its exacerbation though, the definitive pre-disposing factors and factors related to acute exacerbation have not been determined in the context of Nepal.Objective To find out the pre-disposing factors and the related causative agents for COPD.Method A cross sectional study was conducted in a tertiary care hospital. Patients of all age group who were diagnosed as COPD and admitted in the hospital were included in this study. Patients were interviewed using structured questionnaire. The socio-demographic data including personal and medical history were recorded from those participants. In addition, sputum from those patients was sent for culture to investigate the possible responsible pathogens as well as its antibiotic sensitivity pattern.Result A total of 150 patients having Acute Exacerbation of Chronic Obstructive Pulmonary Disease (AECOPD) who have admitted from either emergency or out-patient department of the hospital were included in this study. Among the total number of patients, more than half of them were female (n=82). In addition, analysis of occupations shows that most of them were either farmer (36.0%) or housewife (30.7%). In total studied patients (n=150), most of them were using traditional firewood (83%) for cooking purpose and majority of patients (91%) were smokers. Most of the sputum samples show growth of gram-positive cocci (26.7%) and gram negative bacilli (27.5%). Considering the overall sensitivity pattern, the higher sensitivity was recorded for Co-trimoxazole and Ciprofloxacin while higher rate of resistance was noted for Penicillin group of drugs. The most widely used antibiotics were found to be Cephalosporin group of drugs (68%).Conclusion The present study revealed that the case of COPD is more in female and the commonest pre-disposing factor is found to be smoke/firewood. Cephalosporin group of drugs is the most commonly prescribed drug.
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Shrestha R, Pant A, Shakya Shrestha S, Shrestha B, Gurung RB, Karmacharya BM. A Cross-Sectional Study of Medication Adherence Pattern and Factors Affecting the Adherence in Chronic Obstructive Pulmonary Disease. Kathmandu Univ Med J (KUMJ) 2016; 13:64-70. [PMID: 26620752 DOI: 10.3126/kumj.v13i1.13756] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Chronic obstructive pulmonary disease (COPD) is considered as a major health problem, associated with mortality and morbidities. Various disease management strategies have been established to optimize patient's longevity and functional status where patient adherence to the prescribed treatment plays a key role. Poor adherence to medication is common among COPD patients and is affected by number of factors like number of medicines, delivery devices and patient-related factors. OBJECTIVE This study aims to investigate the adherence pattern in the management of COPD and factors affecting patient adherence to the prescribed treatment. METHOD This study is a cross-sectional study which was conducted in a tertiary care hospital. Those patients suffering from COPD of all age were enrolled in this study and prior informed consent was obtained from patients. The structured questionnaire was used to interview those patients. RESULT Total 100 patients were enrolled in this study, among which most patients (45%) were of age groups 60-70 years. Unintentional non-adherence to medication attributed for 65% of patients and the major reason was forgetfulness (52.3%). Most patients had discontinued the medication due to experience of side effects (63.3%). The result showed significant association between adherence and polypharmacy (p=0.00). However, there was no significant association between adherence and age, sex, mode of administration of drugs, technics to use delivery devices etc. CONCLUSION Majority of COPD patients were elderly (mean age= 68.4 years). Forgetfulness was associated with medication non-adherence. Most of the patients had discontinued medication because of side effects. Polypharmacy is one of the major factors associated with non-adherence to medication in COPD.
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Affiliation(s)
- R Shrestha
- Department of Pharmacology School of Medical Sciences, Kathmandu University. Research & Development Division Dhulikhel Hospital, Kathmandu University Hospital
| | - A Pant
- Department of Pharmacology School of Medical Sciences, Kathmandu University. Department of Human Biology Schools of Science & Medical Sciences Kathmandu University
| | - S Shakya Shrestha
- Department of Pharmacology School of Medical Sciences, Kathmandu University. Research & Development Division Dhulikhel Hospital, Kathmandu University Hospital
| | - B Shrestha
- Department of Pharmacology School of Medical Sciences, Kathmandu University. Department of Human Biology Schools of Science & Medical Sciences Kathmandu University
| | - R B Gurung
- Department of Internal Medicine Dhulikhel Hospital, Kathmandu University Hospital
| | - B M Karmacharya
- Department of Community Program Dhulikhel Hospital, Kathmandu University Hospital
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Pant A, Asthana J, Yadav AK, Rathor L, Srivastava S, Gupta MM, Pandey R. Verminoside mediates life span extension and alleviates stress in Caenorhabditis elegans. Free Radic Res 2015; 49:1384-92. [PMID: 26189547 DOI: 10.3109/10715762.2015.1075017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The discovery of bioactive molecules modulating aging in living organism promotes development of natural therapeutics for curing age-related afflictions. The progression in age-related disorders can be attributed to increment in intracellular reactive oxygen species (ROS) and oxidative stress level. To this end, we isolated an iridoid verminoside (VMS) from Stereospermum suaveolens (Roxb.) DC. and evaluated its effect on Caenorhabditis elegans. The present study delineates VMS-mediated alteration of intracellular ROS, oxidative stress, and life span in C. elegans. The different tested doses of VMS (5 μM, 25 μM, and 50 μM) were able to enhance ROS scavenging and extend mean life span in C. elegans. The maximal life span extension was observed in 25 μM VMS, that is, 20.79% (P < 0.0001) followed by 9.84% (P < 0.0001) in 5 μM VMS and 8.54% (P < 0.0001) in 50 μM VMS. VMS was able to alleviate juglone-induced oxidative stress and enhanced thermotolerance in worms. The stress-modulating and ROS-scavenging potential of VMS was validated by increment in mean survival by 29.54% (P < 0.0001) in VMS-treated oxidative stress hypersensitive mev-1 mutant strain. Furthermore, VMS modulates expression of DAF-16 (a FoxO transcription factor) promoting stress resistance and longevity. Altogether, our results suggest that VMS attenuates intracellular ROS and stress (oxidative and thermal) level promoting longevity. The longevity and stress modulation can be attributed to VMS-mediated alterations in daf-16 expression which regulates insulin signaling pathway. This study opens doors for development of phytomolecule-based therapeutics for prolonging life span and managing age-related severe disorders.
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Affiliation(s)
- A Pant
- a Microbial Technology and Nematology Department,CSIR-Central Institute of Medicinal and Aromatic Plants , Lucknow , India
| | - J Asthana
- a Microbial Technology and Nematology Department,CSIR-Central Institute of Medicinal and Aromatic Plants , Lucknow , India
| | - A K Yadav
- b Analytical Chemistry Division, CSIR-Central Institute of Medicinal and Aromatic Plants , Lucknow , India
| | - L Rathor
- a Microbial Technology and Nematology Department,CSIR-Central Institute of Medicinal and Aromatic Plants , Lucknow , India
| | - S Srivastava
- a Microbial Technology and Nematology Department,CSIR-Central Institute of Medicinal and Aromatic Plants , Lucknow , India
| | - M M Gupta
- b Analytical Chemistry Division, CSIR-Central Institute of Medicinal and Aromatic Plants , Lucknow , India
| | - R Pandey
- a Microbial Technology and Nematology Department,CSIR-Central Institute of Medicinal and Aromatic Plants , Lucknow , India
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Bigliardi PL, Neumann C, Teo YL, Pant A, Bigliardi-Qi M. Activation of the δ-opioid receptor promotes cutaneous wound healing by affecting keratinocyte intercellular adhesion and migration. Br J Pharmacol 2014; 172:501-14. [PMID: 24628261 PMCID: PMC4292964 DOI: 10.1111/bph.12687] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 02/28/2014] [Accepted: 03/06/2014] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND AND PURPOSE In addition to its analgesic functions, the peripheral opioid receptor system affects skin homeostasis by influencing cell differentiation, migration and adhesion; also, wound healing is altered in δ-opioid receptor knockout mice (DOPr–/–). Hence, we investigated δ-opioid receptor effects on the expression of several proteins of the desmosomal junction complex and on the migratory behaviour of keratinocytes. EXPERIMENTAL APPROACH Expression levels of desmosomal cadherins in wild-type and DOPr–/– mice, and the morphology of intercellular adhesion in human keratinocytes were analysed by immunofluorescence. To investigate the δ-opioid receptor activation pathway, protein expression was studied using Western blot and its effect on cellular migration determined by in vitro live cell migration recordings from human keratinocytes. KEY RESULTS Expression of the desmosomal cadherins, desmogleins 1 and 4, was up-regulated in skin from DOPr–/– mice, and down-regulated in δ-opioid receptor-overexpressing human keratinocytes. The localization of desmoplakin expression was rearranged from linear arrays emanating from cell borders to puncta in cell periphery, resulting in less stable intercellular adhesion. Migration and wound recovery were enhanced in human keratinocyte monolayers overexpressing δ-opioid receptors in vitro. These δ-opioid receptor effects were antagonized by specific PKCα/β inhibition indicating they were mediated through the PKC signalling pathway. Finally, cells overexpressing δ-opioid receptors developed characteristically long but undirected protrusions containing filamentous actin and δ-opioid receptors, indicating an enhanced migratory phenotype. CONCLUSION AND IMPLICATIONS Opioid receptors affect intercellular adhesion and wound healing mechanisms, underlining the importance of a cutaneous neuroendocrine system in wound healing and skin homeostasis. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2
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Affiliation(s)
- P L Bigliardi
- Institute of Medical Biology, Agency for Science Technology & Research (A*STAR), Singapore; Division of Rheumatology, National University Hospital, University Medicine Cluster, Singapore
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12
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Abstract
Apocrine skin carcinoma is an aggressive cutaneous tumour. We report a case of apocrine carcinoma developing in a naevus sebaceous of scalp in a 45 years old male. Malignant transformation of Naevus sebaceous is a rare complication usually found in elderly patients. Most of these tumours are basal cell carcinoma or squamous cell carcinoma. Only few cases of apocrine carcinoma on naevus sebaceous have been previously reported. This report highlights the potential of naevus sebaceous for malignant transformation.
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Affiliation(s)
- Upama Paudel
- Department of Dermatology, Tribhuvan University Teaching Hospital, Maharajgunj Medical campus, Kathmandu, Nepal.
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Jha R, Shrestha A, Pant A, Adhikari RC, Karki S. Comment on "status of pathology professionals". J Nepal Health Res Counc 2012; 10:173-175. [PMID: 23034384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In 2012 Jan issue, Journal of Nepal Health Research Council published an article "Status of Pathology Professionals" by Mishra SK affiliated to Concern for Public Health and Development (C-PHD), Kathmandu, Tiwari BR affiliated to Department of Clinical Microbiology, People's Dental College, Tribhuwan University and Yadav BK from Department of Clinical Biochemistry, Institute of Medicine, Kathmandu, TribhuwanUniversity, Nepal.As a result, comments were sent to JNHRC, and are published below.
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Pant A, Lee I, Lurain J, Schink J, Kim J. MK2206, an orally active allosteric AKT inhibitor, reverses progestin resistance in endometrial cancer. Gynecol Oncol 2011. [DOI: 10.1016/j.ygyno.2011.07.062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
ABSTRACTAn investigation of the stability and electrical characteristics of Aluminum-Copper bilayer films on SiO2 has been carried out. In this investigation, a thin layer of sputtered aluminum is used as a diffusion barrier/adhesion promoter between the copper and SiO2. The electrical performance of these structures when subjected to thermal cycles and applied biases is determined. The interactions and diffusion of copper through aluminum into SiO2 was investigated using both blanket films and MOS capacitors. Results are compared with those obtained from structures of Al and Cu metallization on SiO2. Samples were annealed at various temperatures in the range of 200°C to 500°C. Analysis using four-point probe resistivity measurements, X-ray diffraction, and Rutherford Back Scattering were carried out. MOS capacitors are used to establish performance under applied bias. Capacitance-Voltage characteristics of formed alloys are discussed. These results will be presented and discussed in view of the applicability of aluminum as the adhesion promoter for copper interconnections on SiO2.
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16
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Xiao C, Niu T, Morelli JE, Paz-Soldan C, Dreval M, Elgriw S, Pant A, Rohraff D, Trembach D, Hirose A. Design and initial operation of multichord soft x-ray detection arrays on the STOR-M tokamak. Rev Sci Instrum 2008; 79:10E926. [PMID: 19044581 DOI: 10.1063/1.2953493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Two miniature pinhole camera arrays for spatially and temporally resolved measurements of soft x-ray emission have been designed and installed on the STOR-M tokamak. Each array consists of a photodiode array, with one array viewing vertically and one viewing horizontally through a plasma cross section. Preamplifiers with fixed gains of 10(5) VA and custom built amplifiers with variable gains are used for signal amplification. Digitizers with 14 bit resolution and 3 MSs sampling rate are used for data acquisition. In the initial operation, an Al foil with a thickness of 1.8 microm installed for one array and Be filter of 7.6 microm installed for the other array are used to test signal strength. Initial tests have identified sawtooth oscillations and 20 kHz fluctuations, which are also detected by Mirnov coils, superimposed on the sawtooth oscillations.
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Affiliation(s)
- C Xiao
- Plasma Physics Laboratory, University of Saskatchewan, Saskatoon SK S7N 5E2, Canada.
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17
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Bhosale SH, Pant A, Khan MI. Purification and characterization of putative alkaline [Ni-Fe] hydrogenase from unicellular marine green alga, Tetraselmis kochinensis NCIM 1605. Microbiol Res 2007; 164:131-7. [PMID: 17321121 DOI: 10.1016/j.micres.2006.11.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2006] [Revised: 07/21/2006] [Accepted: 11/08/2006] [Indexed: 11/19/2022]
Abstract
Hydrogenase enzyme from the unicellular marine green alga Tetraselmis kochinensis NCIM 1605 was purified 467 fold to homogeneity. The molecular weight was estimated to be approximately 89kDa by SDS-PAGE. This enzyme consists of two subunits with molecular masses of approximately 70 and approximately 19kDa. The hydrogenase was found to contain 10g atoms of Fe and 1g of atom of Ni per mole of protein. The specific activity of hydrogen evolution was 50micromol H(2)/mg/h of enzyme using reduced methyl viologen as an electron donor. This hydrogenase enzyme has pI value approximately 9.6 representing its alkaline nature. The absorption spectrum of the hydrogenase enzyme showed an absorption peak at 425nm indicating that the enzyme had iron-sulfur clusters. The total of 16 cysteine residues were found per mole of enzyme under the denaturing condition and 20 cysteine residues in reduced denatured enzyme indicating that it has two disulfide bridges.
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Affiliation(s)
- S H Bhosale
- Biochemical Sciences Division, National Chemical Laboratory, Pune, Maharashtra, India
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18
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Zinjarde S, Chinnathambi S, Lachke AH, Pant A. Isolation of an emulsifier from
Yarrowia lipolytica
NCIM 3589 using a modified mini isoelectric focusing unit. Lett Appl Microbiol 2003. [DOI: 10.1046/j.1472-765x.1997.00355.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- S. Zinjarde
- Division of Biochemical Sciences, National Chemical Laboratory, Pune, India
| | - S. Chinnathambi
- Division of Biochemical Sciences, National Chemical Laboratory, Pune, India
| | - A. H. Lachke
- Division of Biochemical Sciences, National Chemical Laboratory, Pune, India
| | - A. Pant
- Division of Biochemical Sciences, National Chemical Laboratory, Pune, India
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19
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Abstract
Birds in V formations are frequently observed and two main hypotheses have emerged to explain this particular geometry: (i) it offers aerodynamic advantages and (ii) it is used to improve visual communication. Both explanations require a bird to track its predecessor. However, most V-formations observed in nature are small and the distribution of wing-tip spacings has a large variation. This suggests that tracking the lateral position of the preceding bird is a difficult task. Control theorists, when trying to control platoons of vehicles, also noted that predecessor following is difficult. In this paper, we apply a result from systems theory to explain the observations of bird V-formations. The strength of this result is that it does not rely on the details of the bird flight model. Thus we claim that formation flight is inherently difficult for birds.
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Affiliation(s)
- P Seiler
- Department of Mechanical Engineering, University of California, 2162 Etcheverry Hall Berkeley, CA 94704, USA.
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Pandey JS, Sayami G, Dali S, Shrestha HG, Shrestha B, Adhikari RC, Bashyal R, Pant A. FINE NEEDLE ASPIRATION CYTOLOGY OF BREAST LUMP IN T.U. TEACHING HOSPITAL. JNMA J Nepal Med Assoc 2003. [DOI: 10.31729/jnma.851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
This is a retrospective study of fine needle aspiration cytology of breast lesionsperformed between May 1998 and April 2000. During this period, a total of 2001 fineneedle aspirations were done in the Tribhuvan Universtiy Teaching Hospital (TUTH),of which 470 (23.48 %) were of the breast. Fibrocystic disease found to be the mostfrequent and was diagnosed in 183 cases (38.9%). Fibroadenoma was the third commonpathological condition, numbering 61 (12.9%). Malignant conditions of the breastwere 72 cases (15.3%).During these two years, histological diagnosis was available in 154 cases. Histologicalexamination revealed benign conditions in 74 cases (48%), malignancy in 59 cases(38.3%) and inflammatory & lactational changes in 21 cases (13.7%). Out of these154 cases, 71 cases had also undergone fine needle aspiration cytology. The 36 casesdiagnosed as benign cytologically, 34 cases were also benign histologically, whereas 2cases turned out to be malignant. Out of 37 cases that were histologically malignant,on cytology 35 cases were diagnosed as malignant. The sensitivity and specificity ofcytopathological diagnosis for breast lesions was 100% and 94.6% respectively.Inflammatory lesions correlated well cytologically and histolgically.FNAC is a safe and rapid diagnostic method for evaluation of various lesions. However,there are possibilities of false negative and false positive results because of wide rangeof appearance of breast lesions.Key Words: Breast lumps, Fine Needle Aspiration Cytology, Benign Lesions,Malignant Lesions, Histopathology and Correlation.
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Abstract
Palm oil mill effluent (POME), from a factory site in India contained about 250,000 mg l(-1) chemical oxygen demand (COD), 11,000 mg l(-1) biochemical oxygen demand, 65 mg l(-1) total dissolved solids and 9000 mg l(-1) of chloroform-soluble material. Treatment of this effluent using Yarrowia lipolytica NCIM 3589, a marine hydrocarbon-degrading yeast isolated from Mumbai, India, gave a COD reduction of about 95% with a retention time of two days. Treatment with a chemical coagulant further reduced the COD and a consortium developed from garden soil clarified the effluent and adjusted the pH to between 6 and 7. The complete treatment reduced the COD content to 1500 mg l(-1) which is a 99% reduction from the original.
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Affiliation(s)
- N Oswal
- Division of Biochemical Sciences, National Chemical Laboratory, Pune, India
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22
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Deshpande AU, Apte GS, Bahulikar RA, Lagu MD, Kulkarni BG, Suresh HS, Singh NP, Rao MK, Gupta VS, Pant A, Ranjekar PK. Genetic diversity across natural populations of three montane plant species from the Western Ghats, India revealed by intersimple sequence repeats. Mol Ecol 2001; 10:2397-408. [PMID: 11742544 DOI: 10.1046/j.0962-1083.2001.01379.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [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: 11/20/2022]
Abstract
We analysed genetic diversity across the natural populations of three montane plant species in the Western Ghats, India; Symplocos laurina, Gaultheria fragrantissima and Eurya nitida using intersimple sequence repeat (ISSR) markers. These markers revealed genetic diversity within the populations of these plants from Nilgiri and also between two populations of S. laurina from Nilgiri and Amboli. Genetic variation within and between populations was analysed using various parameters such as total heterozygosity (HT), heterozygosity within population (HS), diversity between populations (DST), coefficient of population differentiation (GST), genetic distance (D) and gene flow (Nm). Total heterozygosity (HT) was higher for S. laurina (0.238) than for G. fragrantissima (0.172) and E. nitida (0.182). Two populations of S. laurina, separated by > 1000 km, showed a high within-population variation (53.7%) and a low gene flow (Nm = 0.447). upgma phenograms depicted a tendency of accessions to group according to their geographical locations in all the three plant species. The insight gained into the genetic structure of these plant populations might have implications in developing in situ and ex situ conservation strategies.
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Affiliation(s)
- A U Deshpande
- Division of Biochemical Sciences, National Chemical Laboratory, Pune 411008, India
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23
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Abstract
A hydrocarbon degrader isolated from a chronically oil-polluted marine site was identified as Rhodococcus sp. on the basis of morphology, fatty acid methyl ester pattern, cell wall analysis, biochemical tests and G + C content of DNA. It degraded up to 50% of the aliphatic fraction of Assam crude oil, in seawater supplemented with 35 mM nitrogen as urea and 0.1 mM phosphorus as dipotassium hydrogen orthophosphate, after 72 h at 30 degrees C and 150 revolutions per minute. The relative percentage of intracellular fatty acid was higher in hydrocarbon-grown cells compared to fructose-grown cells. The fatty acids C16, C16:1, C18 and C18:1 were constitutively present regardless of the growth substrate. In addition to these constitutive acids, other intracellular fatty acids varied in correlation to the hydrocarbon chain length supplied as a substrate. When grown on odd carbon number alkanes, the isolate released only monocarboxylic acids into the growth medium. On even carbon number alkanes only dicarboxylic acids were produced.
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Affiliation(s)
- S L Sharma
- Division of Biochemical Sciences, National Chemical Laboratory, Pune, India
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24
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Niture SK, Pant A, Kumar AR. Active site characterization of the single endo-polygalacturonase produced by Fusarium moniliforme NCIM 1276. Eur J Biochem 2001; 268:832-40. [PMID: 11168425 DOI: 10.1046/j.1432-1327.2001.01959.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Fusarium moniliforme NCIM 1276 isolated from a tropical mangrove ecosystem produces a single extracellular endo-polygalacturonase with an M(r) of 38 kDa and a carbohydrate content of 4%. It has an alkaline pI of 8.1. The K(m) is 0.12 mg.mL(-1), V(max) is 111.1 micromol.min(-1).mg(-1) and the kcat is 4200 min-1. It has a pH optimum of 4.8. Kinetic and fluorescence data show that tryptophan is involved in binding. An arginine residue at or near the active site may be involved in extended binding of the substrate. A carboxylate and a histidine residue are involved in catalysis. These data are discussed with reference to current literature.
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Affiliation(s)
- S K Niture
- Division of Biochemical Sciences, National Chemical Laboratory, Pune, India
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25
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Abstract
A protease-producing, crude oil degrading marine isolate was identified as Nocardiopsis sp. on the basis of the morphology, cell wall composition, mycolic acid analysis and DNA base composition. The Nocardiopsis produces two extracellular proteases, both of which are alkaline serine endopeptidases. Protease I was purified to homogeneity by chromatography on CM-Sephadex at pH 5.0 and pH 9.0. Protease II was purified using DEAE-cellulose, Sephadex G-50, phenyl-Sepharose and hydroxyapatite chromatography. Protease I and II had almost similar M(r) of 21 kDa (Protease I) and 23 kDa (Protease II), pI of 8.3 and 7.0 respectively with pH and temperature optima for activity between 10.0 and 11.0 and about 60 degrees C. Specific activities were 152 and 14 U/mg respectively on casein. However, Protease I was antigenically unrelated to Protease II. Both proteases were endopeptidases and required extended substrate binding for catalysis. Both proteases had collagenolytic and fibrinolytic activity but only Protease I had elastinolytic activity. The proteases were chymotrypsin-like with respect to their amino acid compositions and N-terminal sequences.
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Affiliation(s)
- V S Dixit
- Division of Biochemical Sciences, National Chemical Laboratory, 411008, Pune, India
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26
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Abstract
An actinomycete isolated from an oil-contaminated marine environment and identified as Nocardiopsis sp. degraded hydrocarbons and also produced extracellular protease. Conditions for crude oil degradation and simultaneous production of extracellular protease were studied. An alternative approach for bio-augmented clean-up of oil spills using a micro-organism capable of degrading hydrocarbons and recruiting organic nitrogen by producing proteases is reported.
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Affiliation(s)
- V S Dixit
- Division of Biochemical Sciences, National Chemical Laboratory, Pune, India
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Hedrick S, Chuang S, Pant A, Dastidar A. Activity and selectivity of Group VIII, alkali-promoted Mn-Ni, and Mo-based catalysts for C2+ oxygenate synthesis from the CO hydrogenation and CO/H2/C2H4 reactions. Catal Today 2000. [DOI: 10.1016/s0920-5861(99)00245-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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29
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Gautam S, Gupta ID, Batra L, Sharma H, Khandelwal R, Pant A. Psychiatric morbidity among victims of bomb blast. Indian J Psychiatry 1998; 40:41-5. [PMID: 21494441 PMCID: PMC2964816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Thirty one victims of bomb blast in a bus caused by terrorist activity in Dausa district, Rajasthan on 22.5.96, were evaluated for psychological reactions 3 days & 2 weeks after the incident. All hospitalized & non hospitalised bomb blast victims were assessed within 3 days of injury by objective predictors (percent of burnt area, facial disfigurement, limb amputations, fractures etc.) and subjective predictors (emotional distress and perceived social support). Detailed history, physical and mental state examination of all patients was carried out and for those having scores more then 17 on GHQ-60 (Hindi version), IPIS was administered. Diagnosis was made by 3 senior consultant psychiatrists of Psychiatric Centre, Jaipur, on the basis oflCD-10. At day 3 of 31 patients studied 11 (35.45%) had psychiatric morbidity. Out of which 6 (19.35%) had acute stress reaction, 3 (9.68%) had depression and 2 (6.45%) dissociative amnesia. Most commonly reported symptoms on IPIS were depersonalisation, derealisation, sleep disturbances specially generalised sleep loss, loss of appetite, nightmares, situational anxiety, depression, mental irritability, dulness of feelings, self blame, guilt, loss of interest, suicidal ideas, and worry about money, spouse, work and children. Most common physical injury was burns, followed by hearing disturbances, wounds received due to glass <& metal pieces and non specific pains and aches. Findings of follow up have been discussed and battery of tests for evaluation of victims of acute trauma has been suggested.
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Affiliation(s)
- S Gautam
- SHIV GAUTAM, M.D., (Psych.), D.P.M., MNAMS., Professor & Head, Department of Psychiatry, SMS Medical College, Jaipur
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30
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Zinjarde S, Pant A, Deobagkar D. World J Microbiol Biotechnol 1997; 14:299-300. [DOI: 10.1023/a:1008819221510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Rao MN, Kembhavi AA, Pant A. Role of lysine, tryptophan and calcium in the beta-elimination activity of a low-molecular-mass pectate lyase from Fusarium moniliformae. Biochem J 1996; 319 ( Pt 1):159-64. [PMID: 8870663 PMCID: PMC1217749 DOI: 10.1042/bj3190159] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [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: 02/02/2023]
Abstract
An extracellular pectate lyase from Fusarium moniliformae was purified to homogeneity by affinity chromatography followed by gel filtration, with a yield of 76.5%. Laser desorption MS of the enzyme gave a molecular mass of 12,133.5 +/- 2.5 Da. The pectate lyase was a glycoprotein with a 5% carbohydrate content and had a pl value of 9.1. Atomic-emission spectrometry showed that Ca2+ was a part of the holoenzyme held by carboxy groups of the protein. These results support the hypothesis of a putative Ca2+ site suggested by Yodder, Keen and Jurnak [(1993) Science 260, 1503-1507] in the crystal structure of pectate lyase C of Erwinia chrysanthemi. Loss of Ca2+ was observed by treatment with EGTA or carboxy-modifying Woodward's reagent K, with subsequent loss of enzyme activity. Tryptophan fluorescence quenching showed that Ca2+ does not affect binding of substrate to enzyme. Chemical-modification and substrate-protection studies showed the presence of lysine and tryptophan at or near the active site of the pectate lyase. Chemically modified enzyme showed no major structural changes as determined by CD. Amino acid analyses of native, trinitrobenzenesulphonate (TBNS)-treated and substrate-protected TNBS-treated enzyme showed that a single essential residue of lysine is present at or near the active-site. Substrate-affinity studies showed that tryptophan could be essential for substrate binding, whereas lysine could be involved in the catalysis. Fluorescence quenching further confirmed the involvement of tryptophan in substrate binding. The reaction mechanism involving beta-elimination by this enzyme is discussed.
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Affiliation(s)
- M N Rao
- Division of Biochemical Sciences, National Chemical Laboratory, Pune, India
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Rao MN, Kembhavi AA, Pant A. Implication of tryptophan and histidine in the active site of endo-polygalacturonase from Aspergillus ustus: elucidation of the reaction mechanism. Biochim Biophys Acta 1996; 1296:167-73. [PMID: 8814223 DOI: 10.1016/0167-4838(96)00067-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The mechanism of action for the hydrolysis of polygalacturonic acid by the enzyme endo-polygalacturonase (poly(1,4-alpha-D-galacturonide) glycanohydrolase, EC 3.2.1.15) was investigated. The enzyme from Aspergillus ustus was purified to homogeneity and used for the study. The endo-polygalacturonase had a molecular weight of 36,000 daltons, a pI of 8.3, specific activity of 785 units/mg, Km of 0.82 mg/ml, and Vmax of 976 micromoles of product min-1 mg-1. Amino acids involved in the catalysis were identified by chemical modification and the active site characterized. Inhibition by hydroxynitrobenzyl bromide and diethylpyrocarbonate, followed by substrate protection studies showed that tryptophan and histidine were involved at or near the active site. Kinetic constants of partially inhibited enzyme, suggest the involvement of tryptophan in substrate binding and histidine in catalysis. Quenching of tryptophan fluorescence of the enzyme in the presence of polygalacturonic acid substantiated the conclusion that tryptophan was involved in substrate binding. An isotope effect of 1.8 was observed with deuterated water on the Vmax of the endo-polygalacturonase, with the proton inventory giving a linear relationship. The proposed mechanism involves a single proton transfer from the histidine residue of the enzyme to the glycosidic oxygen and hydrolysis by the addition of a water molecule.
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Affiliation(s)
- M N Rao
- Division of Biochemical Sciences, National Chemical Laboratory, Pune, India
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Abstract
The simultaneous addition of dithiothreitol (DTT), mercaptoethanol, and glutathione (30 microM each) and CH3Hg+ to Nostoc calcicola cells reduced CH3Hg+ uptake in the order GSH > DTT > mercaptoethanol. However, the preexposure of cyanobacterial cells to similar thiols resulted in different pattern of CH3Hg+ uptake in the sequence: GSH > mercaptoethanol > DTT. Light-grown cyanobacterial cells demonstrated a faster initial uptake of CH3Hg+ (rate 0.619 mumol CH3Hg+ mg-1 protein min-1, 10 min) with a biphasic pattern saturating at 30 min (bioconcentration factor = 2.7 x 10(3)). 3-(3,4-Dichlorophenyl)-1,1'-dimethyl urea (30 microM) reduced the uptake rate by 5% with a corresponding 33% reduction in CH3Hg+ accumulation. Dark exposure (24 hr) of cells reduced the CH3Hg+ uptake rate (22.3%) accompanied by a considerable decline in the bioconcentration factor (1.4 x 10(3)). Of the four permeabilizers used, p-chloromercuribenzoate (1 microM) proved most effective in altering the CH3Hg+ uptake kinetics while dimethyl sulfoxide (5%) and cetyl trimethylammonium bromide (1%) lowered the bioconcentration factor to 2.2 x 10(3) and 1.2 x 10(3), respectively. After toluene exposure, however, the cells revealed no sign of CH3Hg+ uptake. The data have been discussed in light of the role(s) of thiols, photoautotrophy, and membrane integrity in regulating the cellular influx of CH3Hg+.
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Affiliation(s)
- A Pant
- Algal Research Laboratory, Banaras Hindu University, Varanasi, India
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Abstract
The proteolytic activity produced by a Bacillus subtilis isolated from a hot spring was investigated. Maximum protease production was obtained after 38 h of fermentation. Effects of various carbon and nitrogen sources indicate the requirement of starch and bacteriological peptone to be the best inducers for maximum protease production. Requirement for phosphorus was very evident, and the protease was secreted over a wide range of pH 5-11. The partially purified enzyme was stable at 60 degrees C for 30 min. Calcium ions were effective in stabilizing the enzyme, especially at higher temperature. The enzyme was extremely salt tolerant and retained 100% activity in 5M NaCl over 96 h. The molecular weight of the purified enzymes as determined by SDS-PAGE was 28,000. The enzyme was completely inactivated by PMSF, but little affected by urea, sodium dodecyl sulfate, and sodium tripoly phosphate.
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Affiliation(s)
- A A Kembhavi
- Division of Biochemical Sciences, National Chemical Laboratory, Pune, India
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35
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Harjai K, Shah M, Pant A, Kale P, Pathare AV. Amegakaryocytic thrombocytopenic purpura. J Postgrad Med 1992; 38:96-7. [PMID: 1432843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- K Harjai
- Dr. J C Patel Hematology Department, Seth G S Medical College and KEM Hospital, Parel, Bombay
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36
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Pant A, Kale P, Harjai K, Shah M, Pathare AV. Non-A non-B hepatitis induced aplastic anemia. J Postgrad Med 1992; 38:85-6. [PMID: 1432838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- A Pant
- Dr. J C Patel Hematology Dept, Seth GS Medical College and KEM Hospital, Parel, Bombay
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