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Bhadada SK, Bhansali A, Das S, Singh R, Sen R, Agarwal A, Mittal B, Nahar U, Dutta P, Khandelwal N. Fibrous dysplasia & McCune-Albright syndrome: an experience from a tertiary care centre in north India. Indian J Med Res 2011; 133:504-9. [PMID: 21623035 PMCID: PMC3121281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND & OBJECTIVES Fibrous dysplasia (FD) is a rare metabolic bone disease and information available from India is limited to only anecdotal case reports. We describe the clinical profile and therapeutic outcome of 25 patients with FD observed over a period of 14 yr in a tertiary care centre from north India. METHODS In this retrospective study patients (n = 25) with diagnosis of fibrous dysplasia based on either classical radiological features and/or histological evidence on bone biopsy, were analyzed. Associated endocrinopathies if any, were evaluated. The diagnosis of McCune Albright syndrome (MAS) was considered when fibrous dysplasia was accompanied by either café-au-lait macules and/or endocrinopathies. The clinical presentation, biochemical parameters and imaging were analysed. Seven patients received bisphosphonate therapy. The final outcome and side effects were noted. RESULTS Age of the patients ranged from 7 to 48 yr (mean ± SD, 24.2 ± 11.4 yr) with a lag time between onset of symptoms and presentation ranging from 1 to 20 yr (mean ± SD, 6.6 ± 6.2 yr). The mean duration of follow up was 3.5 ± 2.1 yr. Eighteen (72%) patients had polyostotic disease while the remaining had monostotic FD. Eight patients had endocrinopathies: five had acromegaly, one each had gonadotropin independent precocious puberty (GIPP), hyperthyroidism and hypophosphatemic rickets. One child with GIPP later developed hyperthyroidism. McCune Albright syndrome was observed in 10 (40%) patients. A majority of the patients underwent various minor or major surgical procedures and seven patients received bisphosphonates for recurrent pathological fractures. Bone pain was reduced in all bisphosphonate treated patients with a decrease in subsequent fractures. INTERPRETATION & CONCLUSIONS This series of FD patients from north India shows the varying presentations of this rare disease. Medical treatment with bisphosphonates appears to be potentially rewarding.
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Sen J, Agarwal S, Singh S, Sen R, Goel S. Benign vs malignant soft tissue neoplasms: limitations of magnetic resonance imaging. Indian J Cancer 2010; 47:280-6. [PMID: 20587903 DOI: 10.4103/0019-509x.64725] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIMS Various features have been described in the literature to differentiate benign from malignant lesions. The aim of the present study was to study the accuracy of each of these features and that of magnetic resonance imaging (MRI) in diagnosing malignant lesions. MATERIALS AND METHODS Fifty-five consecutive patients presenting with neoplastic (both benign and malignant) lesions diagnosed clinically and on ultrasound were studied and their MRI features were compared with the findings on surgical exploration and histopathologic examination. RESULTS There were 32 (58%) benign and 23 (42%) malignant masses. Malignant masses were more common in patients older than 20 years (83%), and these had symptoms of less than 6 months duration (75%), as against benign lesions. The swelling was painful in 8 malignant masses and these were more common in the upper limbs (61%). Various features of malignant lesions were size more than 5 cm in 83%, change in signal intensity from homogenous on T1-weighted images to heterogenous on T2-weighted images in 74%, irregular margins in 74%, and heterogenous contrast enhancement in 91%. The accuracy of these features was 76%, 58%, 78%, and 60%, respectively. Most benign and malignant lesions were intramuscular in location. A significant number (38%) of benign lesions were located in the intermuscular facial plane. Definitive diagnosis was made in 42% of the lesions. CONCLUSIONS MRI is an excellent modality for evaluating soft tissue neoplasms; however, prediction of a specific diagnosis and differentiation of malignant and benign lesions is not always possible.
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Sen R, Gadagkar R. Natural history and behaviour of the primitively eusocial waspRopalidia marginata(Hymenoptera: Vespidae): a comparison of the two sexes. J NAT HIST 2010. [DOI: 10.1080/00222931003615703] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Bhadada SK, Das S, Bhansali A, Sen R, Bhattachrya A. Visual vignette. Endocr Pract 2009; 15:655. [PMID: 19546048 DOI: 10.4158/ep09168.vvr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Shanbhogue AKP, Sandhu MS, Singh P, Ojili V, Khandelwal N, Sen R. Real time spatial compound ultrasound in the evaluation of meniscal injuries: a comparison study with conventional ultrasound and MRI. Knee 2009; 16:191-5. [PMID: 19059782 DOI: 10.1016/j.knee.2008.10.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2008] [Revised: 10/24/2008] [Accepted: 10/30/2008] [Indexed: 02/02/2023]
Abstract
The aim of this study was to compare real time spatial compound ultrasound (RTCS) and conventional ultrasound with MRI in the evaluation of meniscal injuries. Thirty five patients with clinical suspicion of meniscal injury underwent ultrasound of knee alternating between conventional and compound sonography followed by MRI of the knee on a 1.5 T MR system. The images were compared for their quality and ability to detect meniscal tear. Compound ultrasound significantly improved definition of soft tissue planes, reduced speckle and other noise, improved contrast resolution (p value<0.05) with improved confidence in detection of tears in doubtful cases. Interobserver variability was seen only for conventional ultrasound and the sensitivity, specificity, accuracy were 83.3%, 87.5% and 85.7% for the first observer and 80%, 87.5% and 84.3% for second observer. For compound ultrasound it was same for both the observers with sensitivity, specificity and accuracy being 90% each. Although compound ultrasound improves image quality in the evaluation of meniscal injuries the benefit with respect to detection of tears is only marginal. It is a valuable tool for screening the patients before MRI and we recommend that instead of conventional ultrasound, compound ultrasound should be routinely used for sonographic evaluation of meniscal injuries.
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Mukherjee S, Das P, Sivapathasekaran C, Sen R. Antimicrobial biosurfactants from marineBacillus circulans: extracellular synthesis and purification. Lett Appl Microbiol 2009; 48:281-8. [DOI: 10.1111/j.1472-765x.2008.02485.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Ghalaut PS, Sen R, Dixit G. Role of granulocyte colony stimulating factor (G-CSF) in chemotherapy induced neutropenia. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2008; 56:942-944. [PMID: 19322972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
BACKGROUND In the past decade, there have been many clinical trials investigating the potential benefits of adjunctive therapy with colony stimulating factors (CSFs) both to ameliorate or prevent profound neutropenia and its potentially life threatening consequences. Neutropenia is the most common dose limiting side effects of cytotoxic chemotherapy. We decided to study the effect of same in our patients coming to haematology clinic. AIMS AND OBJECTIVES To see the effect of G-CSF on severity of neutropenia following chemotherapy in patients of haematological malignancies and to see the effect of G-CSF on duration of hospitalization, documented infections and duration of fever as compared to control group in patients with neutropenia following chemotherapy in haematological malignancies. MATERIAL AND METHODS Thirty patients of acute leukemia were prospectively studied. Patients were given G-CSF 24.hours following chemotherapy induced neutropenia and following parameters were observed. (a) median time to ANC recovery (b) incidence and duration of fever (c) duration of hospitalization following chemotherapy (d) incidence of documented infections. The patients were given G-CSF until the neutrophil count was >1000/ml for 3 days or maximum of 7 days. RESULTS Mean age was 29.33 +/- 14 years in G-CSF group and 27.53 +/- 13.75 in control group. Mean duration of neutropenia was 11.4 days (p < 0.05) in G-CSF group and 15.8 days in control group. Mean duration of fever was 8.2 days in G-CSF group and 13.53 days in control group (p < 0.05). Mean duration of hospital stay was 21.33 days in G-CSF group and 25 days in control group (p > 0.05). CONCLUSIONS The study demonstrates that G-CSF administration is efficacious in chemotherapy induced neutropenia by decreasing the duration of neutropenia and duration of fever.
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Sen R, Pratap A, Agrawal A, Adhikary S, Pandey SR. Isolated accessory limb of lower eyelid with multiple dermal appendages. Singapore Med J 2008; 49:e93-e95. [PMID: 18418514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We report the first case in the English literature of an isolated occurrence of accessory limb with multiple dermal appendages in a ten-month-old boy. This condition presented at birth as a limb bud below the left eyelid, multiple dermal appendages in the adjacent part of the face below the left orbit and on the upper part of the face. No anomalies of the ocular structures or central nervous system were identified. Accessory limb with multiple dermal appendages, in the absence of a congenital cystic eye, is an extremely rare condition representing a benign aberration in the developing musculoskeletal system. We present the first of such a case and endeavour to explain the embryological basis behind it.
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Das P, Mukherjee S, Sen R. Antimicrobial potential of a lipopeptide biosurfactant derived from a marine Bacillus circulans. J Appl Microbiol 2008; 104:1675-84. [PMID: 18194244 DOI: 10.1111/j.1365-2672.2007.03701.x] [Citation(s) in RCA: 183] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To isolate the biologically active fraction of the lipopeptide biosurfactant produced by a marine Bacillus circulans and study its antimicrobial potentials. METHODS AND RESULTS The marine isolate B. circulans was cultivated in glucose mineral salts medium and the crude biosurfactant was isolated by chemical isolation method. The crude biosurfactants were solvent extracted with methanol and the methanol extract was subjected to reverse phase high-performance liquid chromatography (HPLC). The crude biosurfactants resolved into six major fractions in HPLC. The sixth HPLC fraction eluting at a retention time of 27.3 min showed the maximum surface tension-reducing property and reduced the surface tension of water from 72 mNm(-1) to 28 mNm(-1). Only this fraction was found to posses bioactivity and showed a pronounced antimicrobial action against a panel of Gram-positive and Gram-negative pathogenic and semi-pathogenic micro-organisms including a few multidrug-resistant (MDR) pathogenic clinical isolates. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of this antimicrobial fraction of the biosurfactant were determined for these test organisms. The biosurfactant was found to be active against Gram-negative bacteria such as Proteus vulgaris and Alcaligens faecalis at a concentration as low as 10 microg ml(-1). The biosurfactant was also active against methicillin-resistant Staphylococcus aureus (MRSA) and other MDR pathogenic strains. The chemical identity of this bioactive biosurfactant fraction was determined by post chromatographic detection using thin layer chromatography (TLC) and also by Fourier transform infrared (FTIR) spectroscopy. The antimicrobial HPLC fraction resolved as a single spot on TLC and showed positive reaction with ninhydrin, iodine and rhodamine-B reagents, indicating its lipopeptide nature. IR absorption by this fraction also showed similar and overlapping patterns with that of other lipopeptide biosurfactants such as surfactin and lichenysin, proving this biosurfactant fraction to be a lipopeptide. The biosurfactant did not show any haemolytic activity when tested on blood agar plates, unlike the lipopeptide biosurfactant surfactin produced by Bacillus subtilis. CONCLUSIONS The biosurfactant produced by marine B. circulans had a potent antimicrobial activity against Gram-positive and Gram-negative pathogenic and semi-pathogenic microbial strains including MDR strains. Only one of the HPLC fractions of the crude biosurfactants was responsible for its antimicrobial action. The antimicrobial lipopeptide biosurfactant fraction was also found to be nonhaemolytic in nature. SIGNIFICANCE AND IMPACT OF THE STUDY This work presents a nonhaemolytic lipopeptide biosurfactant produced by a marine micro-organism possessing a pronounced antimicrobial action against a wide range of bacteria. There is a high demand for new antimicrobial agents because of the increased resistance shown by pathogenic micro-organisms against the existing antimicrobial drugs. This study provides an insight into the search of new bioactive molecules from marine micro-organisms.
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Sen R, Prasad P, Kumar S, Nagi O. Periprosthetic femoral fractures around well fixed implants: a simple method of fixation using LC-DCP with trochanteric purchase. Acta Orthop Belg 2007; 73:200-6. [PMID: 17515232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Periprosthetic fractures of the femur are among the most serious complications in hip surgery. Various classifications have been suggested. At present the Vancouver classification system probably comes closest to the ideal. Most authors recommend internal fixation of the fractures in well-fixed implants (Vancouver type B1). However as the fixation to the proximal fragment has always been a problem, many types of fixation devices have been used. This retrospective study was done to evaluate the efficacy of an LC-DCP with trochanteric purchase, in the fixation of Vancouver type B1 periprosthetic femoral fractures. Our study included 12 patients, 7 male and 5 female with a mean age of 73 years (range: 57 to 91). One patient died due to complications not related to surgery and in another patient the plate was found broken with a loose implant, which was revised. All cases were primary arthroplasties. A long broad LC-DCP was used for the fixation. Purchase in the proximal fragment was obtained with screws in the greater trochanter. Ten fractures united in an average period of 7 months. The mean duration of follow-up was 6.5 years. The final results were evaluated using the Harris hip score. The mean Harris hip score was 85 with a range of 75 to 94.
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Singh R, Sharma AK, Magu NK, Kaur KP, Sen R, Magu S. Extraskeletal osteochondroma in the nape of the neck: a case report. J Orthop Surg (Hong Kong) 2006; 14:192-5. [PMID: 16914787 DOI: 10.1177/230949900601400217] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Extraskeletal osteochondroma in the nape of the neck is rare and its pathological diagnosis is based on radiological and histopathological examination. It is vital that such a diagnosis be considered when a discrete, ossified mass is localised in soft tissues, even at atypical sites. Differential diagnoses include myositis ossificans, a lipomatous lesion, a pseudomalignant osseous tumour, an ossifying fibromyxoid tumour, an extraskeletal chondroma with endochondral ossification, synovial (osteo) chondromatosis, tumoural calcinosis, a synovial sarcoma, and an extraskeletal osteosarcoma. Clinical awareness of this benign entity is important as no malignant transformation or metastasis has been reported. Marginal excision with histopathological identification is the treatment of choice.
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Puttaswamaiah R, Chandran P, Sen R, Kataria S, Gill SS. Deformities in conservatively treated closed fractures of the shaft of the femur in children. Acta Orthop Belg 2006; 72:147-53. [PMID: 16768256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
We present the outcome of non-operative management of fractures of the shaft of the femur in children. Thirty children with non-operatively managed unilateral fractures of the shaft of the femur were studied. The mean age was 6.5 years (range: 1.2 to 12). Axial, angular and rotational malunion were assessed clinically and radiologically by plain films and computed tomography (CT). All children had shortening of the fractured limb with a mean shortening of 1.8 cm (range: 0.5 to 3.5). A significant level of shortening was seen in children over 7 years. In the sagittal plane, all had anterior angulation ranging from 4 degrees to 31 degrees (mean: 17.8 degrees) and in the coronal plane, lateral angulation (varus) was seen in 90% (27 patients) with a mean angle of 8.9 degrees. Rotational malunion ranged from -43 degrees to +43 degrees (mean: 9.5 degrees), 30% had rotational malunion of > 20 degrees compared to the uninjured side; 73% had internal rotation malunion and 27% had external rotation malunion. We conclude that non-operative management of fractures of the shaft of the femur in children often results in malunion at the fracture, particularly in the older age group and in comminuted fractures. Perhaps a longer follow-up might have shown lower levels of malunion. Frequent monitoring of fracture position may reduce the occurrence of deformity. It may be appropriate to consider reduction and operative stabilisation of such fractures whenever neces-
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Teoh B, Lyons S, Sen R, Abbott J. 154. J Minim Invasive Gynecol 2005. [DOI: 10.1016/j.jmig.2005.07.153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Nayagam LS, Rajan SG, Khandelwal N, Sen R, Kohli HS, Sud K, Gupta KL, Sakhuja V, Jha V. Bilateral femoral capital avascular necrosis in a renal transplant recipient on tacrolimus-based immunosuppression. Nephrol Dial Transplant 2005; 20:2262-4. [PMID: 16030048 DOI: 10.1093/ndt/gfh982] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Bradford NM, Sen R. Engineering Judgment and the Design That Got Away. JOURNAL OF PROFESSIONAL ISSUES IN ENGINEERING EDUCATION AND PRACTICE 2004. [DOI: 10.1061/(asce)1052-3928(2004)130:2(84)] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Sen R, Singh S, Singh H, Gupta A, Sen J. Clinical profile in gelatinous bone marrow transformation. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2003; 51:585-8. [PMID: 15266925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
OBJECTIVE To study the clinical spectrum associated with gelatinous bone marrow transformation (GMT). METHODS All subjects whose bone marrow aspiration showed pink purple material on Leishman stain underwent a detail history, clinical examination and investigation (biochemical/microbiological/radiological). Additionally, in each subject the smear was stained with special stains of Periodic Acid Schiff and Alcian blue. RESULTS Out of total 1498 marrows, 65 showed evidence of GMT. All of these had anaemia. The associated clinical spectra of diseases noticed were: Infection (31 cases), Nutritional deficiency (5 cases), Haematological disorders (Aplastic/toxic depression) (17 cases), Malignancies (3 cases), and Miscellaneous (9 cases). CONCLUSION Based on the heterogenecity of associated clinical disorders, GMT indicates severe illness and not a particular disease. GMT may be a result of bioregulatory process (which presently needs further prospective studies) that are activated in different pathologic conditions but resulting in similar lesion in the bone marrow and so till then it may be concluded that GMT is a symptom of bone marrow.
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Singh H, Sen R, Singh S, Siwach SB, Singh RM. Utility of intradermal smear in the diagnosis of malaria. Trop Doct 2003; 33:108-10. [PMID: 12680550 DOI: 10.1177/004947550303300220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The objective of this preliminary study was to evaluate the usefulness of the intradermal smear test in the diagnosis of malaria. One hundred cases of suspected malaria (having received no prior antimalarials) were investigated. Both peripheral blood film (PBF) and intradermal smears (IDS) were simultaneously prepared and patients placed on antimalarial therapy. The slides were repeated for the next 2 days. At admission, 70 cases were positive on PBF--59 were Plasmodium falciparum (PF) and 11 were Plasmodium vivax (PV) whereas surprisingly 62 cases were positive on IDS at admission--61 were PF, one was PV. IDS identified two more cases of PF [P value (not significant)] but failed to identify any new cases of PV (P value NS). On subsequent days IDS positivity for PF was higher than for PBF (P < 0.05 for day 1 and P < 0.001 for day 2). However, the PV yield was poor for any further statistical evaluation on subsequent days. We conclude that IDS is simple, easy to perform, requires no special infrastructure compared to PBF, and is a helpful diagnostic tool in cases where malaria is strongly suspected but peripheral blood slides are repeatedly negative due to prior use of antimalarial therapy. IDS may be added to routine PBF in malaria (especially PF).
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Björklöf K, Sen R, Jørgensen KS. Maintenance and impacts of an inoculated mer/luc-tagged Pseudomonas fluorescens on microbial communities in birch rhizospheres developed on humus and peat. MICROBIAL ECOLOGY 2003; 45:39-52. [PMID: 12447585 DOI: 10.1007/s00248-002-2018-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2002] [Accepted: 07/01/2002] [Indexed: 05/24/2023]
Abstract
Antagonistic bacteria represent promising biocontrol agents for improving forest production in seedling nurseries or forest soils. The fate of an introduced mer/luc-tagged antagonistic Pseudomonas fluorescens 31K3 was monitored in the rhizosphere of silver birch (Betula pendula) seedlings grown in microcosms containing forest humus or nursery peat. The inoculated strain (10(8) cfu g(-1) soil) was unable to establish in significant numbers in either soil type and turned nonculturable in humus. Detection in both soils was possible only via luminescence of enrichment cultures 80 days post-inoculation. Despite low P. fluorescens survival, inoculation had a positive effect on seedling growth. Limited impact of inoculation on the indigenous microbial communities was identified following analyses of respiration and denitrification potential, community-level physiological profiles and molecular fingerprinting of fungi and eubacteria, and Pseudomonas community structures. The minor changes observed in the indigenous microbial communities, including mycorrhiza development, were not consistent between humus and peat growth substrates. It was concluded that the rhizosphere-related microbial communities developed in both of these highly organic soil systems are highly buffered against introduction of foreign bacteria.
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Niyogi S, Hamon MA, Hu H, Zhao B, Bhowmik P, Sen R, Itkis ME, Haddon RC. Chemistry of single-walled carbon nanotubes. Acc Chem Res 2002; 35:1105-13. [PMID: 12484799 DOI: 10.1021/ar010155r] [Citation(s) in RCA: 1295] [Impact Index Per Article: 58.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this Account we highlight the experimental evidence in favor of our view that carbon nanotubes should be considered as a new macromolecular form of carbon with unique properties and with great potential for practical applications. We show that carbon nanotubes may take on properties that are normally associated with molecular species, such as solubility in organic solvents, solution-based chemical transformations, chromatography, and spectroscopy. It is already clear that the nascent field of nanotube chemistry will rival that of the fullerenes.
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Giri S, Mahajan SK, Sen R, Sharma A. Effects of angiotensin converting enzyme inhibitor on renal function in patients of membranoproliferative glomerulonephritis with mild to moderate renal insufficiency. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2002; 50:1245-9. [PMID: 12568207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
AIM To determine the effect of enalapril, angiotensin-converting-enzyme inhibitor (ACE-I) on progression of renal insufficiency in primary membranoproliferative glomerulonephritis with mild to moderate renal insufficiency. METHOD Thirty patients with histopathologically proved MPGN having hypertension (grade I and II of JNC-VI criteria of hypertension) and mild to moderate impairment of renal function (creatinine clearance varying from 30-80 ml/min, significant albuminuria and serum creatinine 1.2-3.0 mg/dl) were initially treated with diuretics and 3-blockers to bring down BP < 140/90 mm Hg. These patients were then randomly divided into three groups of 10 each, group I--Control; group II--Nifedipine and group III--Enalapril. In group II and III Nifidepine 30 mg/day and in group III Enalapril 10 mg/day respectively were added in addition and treatment was continued for nine months. These patients were followed up monthly for drug efficacy, side effects and any adverse drug reaction. RESULTS Out of 30, 28 patients completed the study. At the end of nine months of treatment the patients of control group revealed significant increase in serum creatinine (1.65 +/- 0.38 to 2.17 +/- 0.31 mg/dl), blood urea (34.0 +/- 3.9 to 40.0 +/- 3.1 mg/dl), and 24 hours albuminuria (3.6 +/- 0.6 to 4.2 +/- 0.6 gm) and decrease in creatinine clearance (60.3 +/- 13.3 to 37.5 +/- 11.8 m/min); however, in enalapril group there was decrease in serum creatinine (1.72 +/- 0.45 to 1.24 +/- 0.58 mg/dl), blood urea (34.6 +/- 4.7 to 28.1 +/- 6.7 mg/dl) and 24 hours albuminuria (3.3 +/- 1.0 to 1.6 +/- 1.1 gm) and increase in creatinine clearance (56A +/- 15.8 to 77.1 +/- 23.5 ml/min). The patients on nifedipine showed statistically nonsignificant changes in creatinine clearance, blood urea and serum creatinine; while albuminuria increased from 3.0 +/- 1.3 to 3.9 +/- 0.4 gm/24 hours (p < 0.01). The blood pressure was well controlled in all patients. None of the patient had side effects leading to withdrawal of drugs. No adverse drug reaction was noted. CONCLUSION ACE-I (enalapril) provided protection against the progression of renal insufficiency in patients of MPGN having hypertension with mild to moderate renal impairment. The renoprotective effects of ACE inhibitor (enalapril) is associated with substantial decrease in albuminuria.
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Singh H, Sen R, Singh S, Malik JP, Siwach SB, Rajput R. Utility of bone marrow aspiration in extrapulmonary tuberculosis. MEDICAL JOURNAL OF INDONESIA 2002. [DOI: 10.13181/mji.v11i3.67] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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Evans DF, Sen R, Warr GG. Structural changes in sodium dodecyl sulfate micelles induced by using counterion complexation by macrocyclic ligands. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100280a004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Sen R, Majumdar D, Bhattacharyya SP, Bhattacharyya SN. Modeling hyperpolarizabilities of some TICT molecules and their analogs. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100131a017] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Tam WF, Wang W, Sen R. Cell-specific association and shuttling of IkappaBalpha provides a mechanism for nuclear NF-kappaB in B lymphocytes. Mol Cell Biol 2001; 21:4837-46. [PMID: 11416157 PMCID: PMC87179 DOI: 10.1128/mcb.21.14.4837-4846.2001] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Mature B lymphocytes are unique in containing nuclear Rel proteins prior to cell stimulation. This activity consists largely of p50-c-Rel heterodimers, and its importance for B-cell function is exemplified by reduced B-cell viability in several genetically altered mouse strains. Here we suggest a mechanism for the cell specificity and the subunit composition of constitutive B-cell NF-kappaB based on the observed properties of Rel homo- and heterodimers and IkappaBalpha. We show that c-Rel lacks a nuclear export sequence, making the removal of c-Rel-containing complexes from the nucleus less efficient than removal of p65-containing complexes. Second, the nuclear import potential of p65 and c-Rel homodimers but not p50-associated heterodimers was attenuated when they were complexed to IkappaBalpha, leading to a greater propensity of heterodimers to be nuclear. We propose that subunit composition of B-cell NF-kappaB reflects the inefficient retrieval of p50-c-Rel heterodimers from the nucleus. Cell specificity may be a consequence of c-Rel-IkappaBalpha complexes being present only in mature B cells, which leads to nuclear c-Rel due to IkappaBalpha turnover and shuttling of the complex.
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Heinonsalo J, Jørgensen KS, Sen R. Microcosm-based analyses of Scots pine seedling growth, ectomycorrhizal fungal community structure and bacterial carbon utilization profiles in boreal forest humus and underlying illuvial mineral horizons. FEMS Microbiol Ecol 2001; 36:73-84. [PMID: 11377775 DOI: 10.1111/j.1574-6941.2001.tb00827.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
We report on the identity of indigenous mycorrhiza forming fungi and rhizosphere/mycorrhizosphere bacterial community carbon source utilization profiles of Scots pine (Pinus sylvestris L.) seedlings grown in boreal forest humus (O) or illuvial (B) mineral horizon containing microcosm growth systems. Based on rDNA (ITS)-RFLP analyses, a total of 10 fungal RFLP taxa were identified from pre-morphotyped mycorrhizas on 7-month-old seedling roots. Hierarchical cluster analysis, including corresponding RFLPs of known fungal species, confirmed root colonization by eight mycorrhizal species. In the O horizon, roots were colonized by e.g. Suillus bovinus, Suillus variegatus, Cenococcum geophilum, Piloderma croceum, Thelephora terrestris and Russula vinicolor. Mycobiont diversity in the mineral B horizon was lower but included Piceirhiza bicolorata and both Suillus species which produced extensive extramatrical mycelium. In comparison to non-colonized soils, rhizosphere and mycorrhizosphere compartments supported significantly higher numbers of bacteria (mean range 10(8)-10(11) cells g(-1) fresh weight (fw)). Specific rhizosphere/mycorrhizosphere 'niche'-linked bacterial communities were detected following multivariate analyses (PCA and CA) of bacterial carbon utilization profiles (Biolog(R) GN microplate). Distinct preferences for amino and carboxylic acids were identified in mineral B horizon rhizospheres whereas a wider range of carbon sources were utilized in the fungal-dominated mycorrhizospheres irrespective of soil types.
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