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| | | Ages | | All Infant: birth-23 months All Child: 0-18 years All Adult: 19+ years Newborn: birth-1 month Infant: 1-23 months Preschool Child: 2-5 years Child: 6-12 years Adolescent: 13-18 years Adult: 19-44 years Middle Aged: 45-64 years Middle Aged + Aged: 45+ years Aged: 65+ years 80 and over: 80+ years Undetermined
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Kiran Tripathi,Ramesh Kumar,Kalpana Bharti,Pramod Kumar,Rajkamal Shrivastav,Shyam Sundar,Kalpana Pai BACKGROUND: Serum adenosine deaminase (ADA) activity increases in diseases where cellular immunity is involved. Since cell-mediated immune responses play a paramount role in the pathogenesis and healing of the visceral leishmaniasis, therefore, the present study was undertaken to evaluate the serum... ( view more ) ADA activity in different pathological conditions. METHODS: Adenosine deaminase was determined in sera of active visceral leishmaniasis (VL) patients at diagnosis and at posttreatment (n=22), healthy controls (n=15), patients with malaria (n=10), leprosy (n=10) and tuberculosis (n=10). RESULTS: Serum levels of ADA were significantly higher in active VL patients as compared to controls and patients with other diseases. ADA levels were also raised in patients with malaria, though not significantly as compared with active VL patients. Sera from VL patients at posttreatment showed significantly decreased ADA levels over sera from patients at diagnosis. CONCLUSIONS: The results therefore suggest that ADA is involved in the pathogenesis and could be used as a clinical marker in the diagnosis of visceral leishmaniasis. ( view less ) Romsha Verma,Radha Ballabh Gupta,Kalpana Singh,Rama Bhasin,Abhay Anand Shukla,Shyam S Chauhan,Kalpana Luthra Host genetic factors play an important role in susceptibility to HIV-1 infection and progression to AIDS. Mutations in genes encoding chemokine receptors and their ligands, viz., CCR5delta32, CCR2-64I and SDF1-3'A are implicated to have protective effects against HIV-1 infection and/or disease prog... ( view more )ression. The distribution of these gene polymorphisms and their role in the course of the disease varies between individuals of different racial, ethnic and risk groups. We have examined the allelic frequencies of CCR5delta32, CCR2-64I and SDF1-3'A in 500 healthy North Indians tested seronegative for HIV-1, by PCR-RFLP. The plasma levels of stromal derived factor (SDF-1) protein were estimated in 75 individuals using ELISA kit. Frequencies of CCR5delta32, CCR2-64I and SDF1-3'A alleles in 500 individuals were 1.5%, 9.1% and 20.4%, respectively. The SDF1-3'A homozygosity was confirmed by PCR product cloning and sequencing. The relative hazard values calculated on the basis of the three locus genotype of each individual revealed high relative hazard values (>0.9). The plasma levels of SDF-1 ranged from 1.77 to 3.42 ng/ml and were comparable between the three genotypes of SDF-1. This is the first study to assess the plasma level of SDF-1 protein in Asian Indians. Low frequency of the protective allele CCR5delta32 observed in this study suggests high vulnerability of North Indians to HIV-1 infection. The precise role of SDF1-3'A in HIV-1 infection needs to be elucidated. ( view less ) Eric A Hehl,Pheroze Joshi,Ganjam V Kalpana,Vinayaka R Prasad Reverse transcriptase (RT) and integrase (IN) are two key catalytic enzymes encoded by all retroviruses. It has been shown that a specific interaction occurs between the human immunodeficiency virus type 1 (HIV-1) RT and IN proteins (X. Wu, H. Liu, H. Xiao, J. A. Conway, E. Hehl, G. V. Kalpana, V. ... ( view more )R. Prasad, and J. C. Kappes, J. Virol. 73:2126-2135, 1999). We have now further examined this interaction to map the binding domains and to determine the effects of interaction on enzyme function. Using recombinant purified proteins, we have found that both a HIV-1 RT heterodimer (p66/p51) and its individual subunits, p51 and p66, are able to bind to HIV-1 IN. An oligomerization-defective mutant of IN, V260E, retained the ability to bind to RT, showing that IN oligomerization may not be required for interaction. Furthermore, we report that the C-terminal domain of IN, but not the N-terminal zinc-binding domain or the catalytic core domain, was able to bind to heterodimeric RT. Deletion analysis to map the IN-binding domain on RT revealed two separate IN-interacting domains: the fingers-palm domain and the carboxy-terminal half of the connection subdomain. The carboxy-terminal domain of IN alone retained its interaction with both the fingers-palm and the connection-RNase H fragments of RT, but not with the half connection-RNase H fragment. This interaction was not bridged by nucleic acids, as shown by micrococcal nuclease treatment of the proteins prior to the binding reaction. The influences of IN and RT on each other's activities were investigated by performing RT processivity and IN-mediated 3' processing and joining reactions in the presence of both proteins. Our results suggest that, while IN had no influence on RT processivity, RT stimulated the IN-mediated strand transfer reaction in a dose-dependent manner up to 155-fold. Thus, a functional interaction between these two viral enzymes may occur during viral replication. ( view less ) K B Kalpana,M Srinivasan,Venugopal P Menon The present work was carried out to evaluate the antioxidant and free radical scavenging activity of aminothiazole derivative by performing various in vitro assays; to study its protective effect on H(2)O(2)-induced oxidative damage on pBR322 DNA and on RBC cellular membrane. The in vitro assays we... ( view more )re performed with different concentrations of aminothiazole derivative (6.15, 12.29, 18.44, 24.59, and 30.73 muM) and the results were compared with standards like ascorbic acid and trolox. Our results clearly indicated that aminothiazole derivative at a dose of 18.44 muM exhibited radical scavenging activity greater than that of ascorbic acid and trolox. The DNA protective effect on pBR322 DNA showed that there was a concentration-dependent inhibition of the disappearance of supercoiled (ccc) form of DNA on incubation with 30 mM H(2)O(2) in the presence of different concentrations of aminothiazole derivative. Thus our compound at 1.5 mM prevents the conversion from supercoiled (ccc) form to open circular form (oc) form of pBR322 DNA. Pretreatment with aminothiazole derivative at a dose of 18.44 muM prevents membrane damage and exhibits an IC(50) value, which is the concentration of the sample required to inhibit 50% of the radical formed greater than that of the standards (ascorbic acid and trolox). Thus our compound of interest aminothiazole derivative exhibits antioxidant and free radical scavenging properties greater than that of standards like ascorbic acid and trolox and thereby protects pBR322 DNA and RBC cellular membrane from free radical induced oxidative damage. ( view less ) Bhaskar C Das,Melissa E Smith,Ganjam V Kalpana Rhabdoid tumors (RTs) are aggressive pediatric malignancies with poor prognosis that arise due to loss of the hSNF5/INI1 tumor suppressor. Molecular studies indicate that cyclin D1, a downstream effector of INI1 is up regulated in RT, and is essential for this tumor formation. Previously we demonst... ( view more )rated that 4-HPR, a synthetic retinoid that targets Cyclin D1, is a potential chemotherapeutic agent for RT. To facilitate further chemical development of this retinoid, and to determine its active moiety, we synthesized small chemical libraries of 4-HPR and tested their cytotoxic effect on RT cells. We synthesized 4-HPR (1) and the derivatives (5a-5n) starting from retinoic acid. First, retinoic acid was converted to acid chloride derivatives, then in the presence of DMF, base, and aniline derivatives, we synthesized the corresponding 4-hydroxy phenyl amine derivatives (5a-5n). This procedure gave 70-90% yield. Then, the 4-HPR derivatives were tested for their ability to inhibit RT cells using an in vitro cell survival assay. We found that the 4-hydroxy group at para-position is essential for cytotoxic activity against RT cells. Furthermore, we identified a few derivatives of 4-HPR with higher cytotoxic potencies than 4-HPR. In addition, we demonstrate that either chloro, fluoro or iodo derivatives at meta-position of phenyl ring retain the cytotoxic activity. Interestingly, substitution of iodo-moiety at meta-position (5j) substantially increased the efficacy (IC(50) approximately 3muM, Fig. 1D). These results indicate that chemical modification of 4-HPR may result in derivatives with increased therapeutic potential for RTs and that halogen substituted 4-HPR that retain the activity can be synthesized for further therapeutic and diagnostic use. ( view less ) Sunil K Hota,Kalpana Barhwal,Shashi B Singh,G Ilavazhagan Hypobaric hypoxia has been implicated with neural degeneration and memory loss. Though there has been considerable knowledge on the role of the p75(NTR) in triggering apoptosis, the occurrence of a similar mechanism in hypoxic stress still remains to be explored. We, in the present study, have trie... ( view more )d to explore the role of p75(NTR) in mediating apoptosis in hypobaric hypoxia. Male Sprague Dawley rats were exposed to an altitude of 7,620 m for different durations. To study the contribution of apoptosis to hypobaric hypoxia induced cell death in the hippocampus, rat brains were examined for the occurrence of apoptosis by determining the number of cells showing DNA breaks using terminal deoxynucleotidyl transferase-mediated UTP nick end labeling (TUNEL) assay and chromatin condensation using Hoechst staining along with estimation of caspase activity and expression of active Caspase 3. Expression of p75(NTR) was studied to determine its possible role in triggering apoptosis in hypobaric hypoxia. Exposure to hypobaric hypoxia was found to progressively increase the number of TUNEL positive and Hoechst positive cells along with increase in caspase activity, thus suggesting apoptotic mode of cell death. p75(NTR) was found to be upregulated on prolonged exposure to hypobaric hypoxia corresponding to the increase in the number of apoptotic cells. Further, reduced expression of p75(NTR) expression by antisense nucleotide administration significantly decreased apoptosis in the CA1 region of hippocampus. Blocking of NMDA receptors by MK801 interestingly decreased p75(NTR) expression and the number of TUNEL positive cells as compared to hypoxic animals. These findings suggest the regulation of p75(NTR) by NMDA receptors and its role in inducing apoptosis in hypoxia. ( view less ) Hung Huynh,Pierce K H Chow,Nallasivam Palanisamy,Manuel Salto-Tellez,Boon Cher Goh,Chi Kuen Lee,Anaji Somani,How Sung Lee,Ramnarayanan Kalpana,Kun Yu,Puay Hoon Tan,Jeanie Wu,Richie Soong,Ming Hui Lee,Henley Hor,Khee Chee Soo,Han Chong Toh,Patrick Tan BACKGROUND/AIMS: Hepatocellular carcinoma is a leading cause of global cancer mortality, with standard chemotherapy being minimally effective in prolonging survival. We investigated if combined targeting of vascular endothelial growth factor protein and expression might affect hepatocellular carcin... ( view more )oma growth and angiogenesis. METHODS: We treated patient-derived hepatocellular carcinoma xenografts with (i) bevacizumab; (ii) rapamycin; and (iii) bevacizumab plus rapamycin. Western blotting was employed to determine changes in the proteins. Apoptosis, vascular endothelial growth factor expression, microvessel density, and cell proliferation were analyzed by immunohistochemistry. RESULTS: Hepatocellular carcinoma growth was inhibited by bevacizumab plus rapamycin treatment to a significantly greater degree than bevacizumab or rapamycin monotherapy. Reductions in tumor growth by bevacizumab plus rapamycin were associated with inhibition of downstream targets of the mammalian target-of-rapamycin pathway, reductions in vascular endothelial growth factor expression, and tumor microvessel density. Potentially additive effects of bevacizumab plus rapamycin included reductions in vascular endothelial growth factor expression, cyclin D1, and cyclin B1. In an intra-peritoneal model of hepatocellular carcinoma, bevacizumab plus rapamycin potently inhibited both intra-liver and intra-abdominal tumor growth, reduced ascites levels, and significantly prolonged mouse survival. CONCLUSIONS: Bevacizumab and rapamycin, which are both clinically approved drugs, may represent a novel molecularly-targeted combination treatment for hepatocellular carcinoma. ( view less ) Manoj V Lohar,Ramswaroop Mundada,Mandar Bhonde,Amol Padgaonkar,Vijaykumar Deore,Nilambari Yewalkar,Dimple Bhatia,Maggie Rathos,Kalpana Joshi,Ram A Vishwakarma,Sanjay KumarWe herein report the design and synthesis of furoquinoline based novel molecules (16-36) and their in vitro multiple targeted inhibitory potency against PI3K/Akt phosphorylation and mTOR using cell based and cell-free kinase assay. In particular, compound 23 in addition to PI3K-mTOR inhibitory pote... ( view more )ncy, it has shown potent inhibition of hypoxia-induced accumulation of HIF-1alpha protein in U251-HRE cell line. The inhibitory activities of compound 23 were confirmed by Western blot analysis, using human non-small cell lung carcinoma H-460 cell line and glioblastoma U251 cell lines. ( view less ) B V S K Chakravarthi,Prasanta Das,Kalpana Surendranath,Anjali A Karande,Chelliah JayabaskaranA fungus was isolated from the stem cuttings of Taxus celebica, which produced paclitaxel in liquid-grown cultures. The fungus was identified as Fusarium solani based on colony characteristics, morphology of conidia and the 26S rDNA sequence. Paclitaxel was identified by chromatographic and spectro... ( view more )scopic comparison with authentic paclitaxel and its cytotoxic activity towards Jurkat cells in vitro. ( view less ) Devendra Verma,Kalpana S Katti,Dinesh R Katti The interfacial interaction and effect of biopolymer on crystal structure of hydroxyapatite in biomimetically synthesized nanocomposites, chitosan/hydroxyapatite (ChiHAP50), polygalacturonic acid/hydroxyapatite (PgAHAP50), and chitosan/polygalacturonic acid/hydroxyapatite (ChiPgAHAP50) have been in... ( view more )vestigated using atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy, and Rietveld analysis. AFM phase images show nano-sized hydroxyapatite particles uniformly distributed in biopolymer. FTIR spectra indicate that chitosan interacts with hydroxyapatite through NH(3)(+) groups, whereas in polygalacturonic acid/hydroxyapatite, dissociated carboxylate groups (COO(-)) form unidentate chelate with calcium atoms. A change in lattice parameters of hydroxyapatite in all nanocomposites is observed using Rietveld analysis. The increase in lattice parameters was most prominent along c-axis in ChiHAP50 and ChiPgAHAP50 nanocomposites, which was 0.388% and 0.319%, respectively. Comparison between particle sizes of hydroxyapatite, determined from AFM and Rietveld analysis, indicates presence of amorphous phase in hydroxyapatite particles, which is believed to be present at the interface of hydroxyapatite and biopolymer. ( view less ) Yogita Ghodke,Arvind Chopra,Kalpana Joshi,Bhushan Patwardhan Methotrexate (MTX) is among the best-tolerated disease-modifying antirheumatic drugs for the treatment of rheumatoid arthritis (RA); major drawbacks of MTX therapy are the large interpatient variability in clinical response and the unpredictable appearance of a large spectrum of side effects. Sever... ( view more )al studies have demonstrated gene polymorphism that may regulate intracellular methotrexate metabolic pathway enzymes linked to drug efficacy and safety, but the evidence available is not yet conclusive. We decided to run a pilot study to determine the incidence of Methylene tetrahydrofolate (MTHFR; C677T, A1298C) and Thymidylate synthase (TS; 5' UTR repeat, 3' UTR deletion) gene polymorphism in rheumatoid arthritis patients in our community (Indian Asian) and further explore its association with MTX response (efficacy, toxicity). Thirty-four naïve RA patients on supervised MTX therapy and 139 healthy controls were genotyped for A1298C and C677T polymorphism of the MTHFR gene and 5' UTR repeat and 3' UTR deletion polymorphism of the TYMS gene by polymerase chain reaction-restriction fragment length polymorphism. Association, if any, between gene polymorphism and MTX response in RA patients was analyzed. The MTHFR A1298C 'C' allele incidence among RA patients (46%) was significantly higher (chi (2) = 4.24, P < 0.05, OR = 1.68). None of the other allele tested showed any association. Although a small sample study, our findings do not suggest a significant association of MTHFR/TS allele/genotype with MTX response in our ethnically distinct Indian (Asian) RA patients. ( view less ) Debashis Sikdar,Shashindra M Pradhan,Dinesh R Katti,Kalpana S Katti,Bedabibhas Mohanty This paper describes a multiscale approach used to model polymer clay nanocomposites (PCNs) based on a new altered phase concept. Constant-force steered molecular dynamics (SMD) is used to evaluate nanomechanical properties of the constituents of intercalated clay units in PCNs, which were used in ... ( view more )the finite element model. Atomic force microscopy and nanoindentation techniques provided additional input to the finite element method (FEM) model. FEM is used to construct a representative PCN model that simulates the composite response of intercalated clay units and the surrounding polymer matrix. From our simulations we conclude that, in order to accurately predict mechanical response of PCNs, it is necessary to take into account the molecular-level interactions between constituents of PCN, which are responsible for the enhanced nanomechanical properties of PCNs. This conclusion is supported by our previous finding that there is a change in crystallinity of polymeric phase due to the influence of intercalated clay units. The extent of altered polymeric phase is obtained from observations of a zone of the altered polymeric phase surrounding intercalated clay units in the "phase image" of PCN surface, obtained using an atomic force microscope (AFM). An accurate FEM model of PCN is constructed that incorporates the zone of the altered polymer. This model is used to estimate elastic modulus of the altered polymer. The estimated elastic modulus for the altered polymer is 4 to 5 times greater than that of pure polymer. This study indicates that it is necessary to take into account molecular interactions between constituents in nanocomposites due to the presence of altered phases, and furthermore provides us with a new direction for the modeling and design of nanocomposites. ( view less ) Naval Kapuriya,Kalpana Kapuriya,Xiuguo Zhang,Ting-Chao Chou,Rajesh Kakadiya,Yu-Tse Wu,Tung-Hu Tsai,Yu-Ting Chen,Te-Chang Lee,Anamik Shah,Yogesh Naliapara,Tsann-Long SuTo improve the chemical stability and therapeutic efficacy of N-mustard, a series of phenyl N-mustard linked to DNA-affinic 9-anilinoacridines and acridine via a urea linker were synthesized and evaluated for antitumor studies. The new N-mustard derivatives were prepared by the reaction of 4-bis(2-... ( view more )chloroethyl)aminophenyl isocyanate with a variety of 9-anilinoacridines or 9-aminoacridine. The antitumor studies revealed that these agents exhibited potent cytotoxicity in vitro without cross-resistance to taxol or vinblastine and showed potent antitumor therapeutic efficacy in nude mice against human tumor xenografts. It also showed that 24d was capable of inducing marked dose-dependent levels of DNA cross-linking by comet assay and has long half-life in rat plasma. ( view less ) Kalpana Surendranath,Anjali A KarandePlant ribosome-inactivating proteins (RIPs) are RNA N-glycosidases that inhibit protein synthesis in cells. Abrin, a type II RIP, is an AB type toxin, which is one of the most lethal types of toxin known. The B chain facilitates the entry of the molecule into the cell, whereas the A chain exerts th... ( view more )e toxic effect. We have generated hybridomas secreting antibodies of the immunoglobulin G class specific to the recombinant A chain of abrin. One monoclonal antibody, namely, D6F10, rescued cells from abrin toxicity. Importantly, the antibody also protected mice from lethal doses of the toxin. The neutralizing effect of the antibody was shown to be due to interference with abrin attachment to the cell surface. ( view less ) Preeti Chavan,Dnyaneshwar Warude,Kalpana Joshi,Bhushan Patwardhan Zingiber officinale Roscoe (common or culinary ginger) is an official drug in Ayurvedic, Indian herbal, Chinese, Japanese, African and British Pharmacopoeias. The objective of the present study was to develop DNA-based markers that can be applied for the identification and differentiation of the co... ( view more )mmercially important plant Z. officinale Roscoe from the closely related species Zingiber zerumbet (pinecone, bitter or 'shampoo' ginger) and Zingiber cassumunar [cassumunar or plai (Thai) ginger]. The rhizomes of the other two Zingiber species used in the present study are morphologically similar to that of Z. officinale Roscoe and can be used as its adulterants or contaminants. Various methods, including macroscopy, microscopy and chemoprofiling, have been reported for the quality control of crude ginger and its products. These methods are reported to have limitations in distinguishing Z. officinale from closely related species. Hence, newer complementary methods for correct identification of ginger are useful. In the present study, RAPD (random amplification of polymorphic DNA) analysis was used to identify putative species-specific amplicons for Z. officinale. These were further cloned and sequenced to develop SCAR (sequence-characterized amplified region) markers. The developed SCAR markers were tested in several non-Zingiber species commonly used in ginger-containing formulations. One of the markers, P3, was found to be specific for Z. officinale and was successfully applied for detection of Z. officinale from Trikatu, a multicomponent formulation. ( view less ) Sunil K Hota,Kalpana Barhwal,Koushik Ray,Shashi B Singh,G Ilavazhagan Exposure to high altitude is known to cause impairment in cognitive functions in sojourners. The molecular events leading to this behavioral manifestation, however, still remain an enigma. The present study aims at exploring the nature of memory impairment occurring on chronic exposure to hypobaric... ( view more ) hypoxia and the possible role of glutamate in mediating it. Increased ionotropic receptor stimulation by glutamate under hypobaric hypoxic conditions could lead to calcium mediated excitotoxic cell death resulting in impaired cognitive functions. Since glutamate is cleared from the synapse by the Glial Glutamate Transporter, upregulation of the transporter can be a good strategy in preventing excitotoxic cell death. Considering previous reports on upregulation of the expression of Glial Glutamate Transporter on ceftriaxone administration, the therapeutic potential of ceftriaxone in ameliorating hypobaric hypoxia induced memory impairment was investigated in male Sprague Dawley rats. Exposure to hypobaric hypoxia equivalent to an altitude of 7600 m for 14 days lead to oxidative stress, chromatin condensation and neuronal degeneration in the hippocampus. This was accompanied by delayed memory retrieval as evident from increased latency and pathlength in Morris Water Maze. Administration of ceftriaxone at a dose of 200 mg/kg for 7 days and 14 days during the exposure on the other hand improved the performance of rats in the water maze along with decreased oxidative stress and enhanced neuronal survival when compared to hypoxic group without drug administration. An increased expression of Glial Glutamate Transporter was also observed following drug administration indicating faster clearance of glutamate from the synapse. The present study not only brings to light the effect of longer duration of exposure to hypobaric hypoxia on the memory functions, but also indicates the pivotal role played by glutamate in mediating excitotoxic neuronal degeneration at high altitude. The therapeutic potential of ceftriaxone in providing neuroprotection in excitotoxic conditions by increasing Glial Glutamate Transporter expression and thereby enhancing glutamate uptake from the synapse has also been explored. ( view less ) Paul K Kiptoo,Kalpana S Paudel,Dana C Hammell,Mohamed O Hamad,Peter A Crooks,Audra L Stinchcomb 6-Beta-naltrexol is the major active metabolite of naltrexone, NTX, a potent mu-opioid receptor antagonist used in the treatment of alcohol dependence and opioid abuse. Compared to naloxone, NTX has a longer duration of action largely attributed to 6-beta-naltrexol. This study was carried out in or... ( view more )der to determine percutaneous absorption of a transdermal codrug of naltrexol, 6-beta-naltrexol-hydroxybupropion codrug (CB-NTXOL-BUPOH), in hairless guinea pigs as well as to evaluate the safety of 6-beta-naltrexol for development as a transdermal dosage form. This codrug may be useful in the simultaneous treatment of alcohol dependence and tobacco addiction. The carbonate codrug traversed the skin at a faster rate than 6-beta-naltrexol. 6-Beta-naltrexol equivalent steady state plasma concentrations of 6.4 ng/ml were obtained after application of the codrug as compared to 1.2 ng/ml from 6-beta-naltrexol base. The steady state plasma concentration of hydroxybupropion after codrug application was 6.9 ng/ml. Skin sensitization and irritation tested in the hairless guinea pigs using the Buehler method revealed that 6-beta-naltrexol had no skin sensitizing potential. The method was validated with a known sensitizer, p-phenylenediamine, which induced sensitization in 90% of the animals. 6-beta-Naltrexol caused only mild transient skin irritation after the initial application of the patch. During subsequent applications, erythema was slightly increased but no skin damage was observed. In conclusion, a transdermal codrug of 6-beta-naltrexol could be a viable alternative treatment for alcohol and opiate abuse. ( view less ) Kalpana Thella,Bhawna Verma,Vimal C Srivastava,Kaushal K Srivastava This study was undertaken to investigate the removal of arsenic (As) and chromium (Cr) from aqueous solution using electrocoagulation (EC) technique. Batch EC studies were performed using iron electrodes to evaluate the influence of various experimental parameters on the removal of metal ions. The ... ( view more )parameters were initial pH (pH(0)), electrolysis time (t), initial concentration (C(0)), electrode gap (g), stirring rate (r) and current density (j). Effect of pH(0) was studied in the range 2.0 to 8.0 while C(0) was varied from 10 to 100 mg/L. As and Cr removal by EC was governed by the chemical dissolution of iron, and the formation of metal-hydrous ferric oxide complexes, which in turn was strongly, influenced by pH(0) and j. Optimum value of pH(0) and j for As and Cr removal were found to be 4.0 and 2.0; and 75 and 50 A/m(2), respectively. Removal efficiency increased with decrease in the value of C(0) and g. The r value of 100 rpm produced sufficient agitation for the proper agglomeration of flocs and optimum removal of ions. ( view less ) Hongwei Wang,Hao Li,Linda B Moore,Michael D L Johnson,Jodi M Maglich,Bryan Goodwin,Olivia R R Ittoop,Bruce Wisely,Katrina Creech,Derek J Parks,Jon L Collins,Timothy M Willson,Ganjam V Kalpana,Madhukumar Venkatesh,Wen Xie,Sool Y Cho,John Roboz,Matthew Redinbo,John T Moore,Sridhar Mani Antagonizing the action of the human nuclear xenobiotic receptor pregnane X receptor (PXR) may have important clinical implications in preventing drug-drug interactions and improving therapeutic efficacy. We provide evidence that a naturally occurring phytoestrogen, coumestrol, is an antagonist of ... ( view more )the nuclear receptor PXR (NR1I2). In transient transfection assays, coumestrol was able to suppress the agonist effects of SR12813 on human PXR activity. PXR activity was assessed and correlated with effects on the metabolism of the anesthetic tribromoethanol and on gene expression in primary human hepatocytes. We found that coumestrol was able to suppress the effects of PXR agonists on the expression of the known PXR target genes, CYP3A4 and CYP2B6, in primary human hepatocytes as well as inhibit metabolism of tribromoethanol in humanized PXR mice. Coumestrol at concentrations above 1.0 microm competed in scintillation proximity assays with a labeled PXR agonist for binding to the ligand-binding cavity. However, mammalian two-hybrid assays and transient transcription data using ligand-binding-cavity mutant forms of PXR show that coumestrol also antagonizes coregulator recruitment. This effect is likely by binding to a surface outside the ligand-binding pocket. Taken together, these data imply that there are antagonist binding site(s) for coumestrol on the surface of PXR. These studies provide the basis for development of novel small molecule inhibitors of PXR with the ultimate goal of clinical applications toward preventing drug-drug interactions. ( view less ) Kalpana Kannan,Andrew D L Nelson,Dorothy E Shippen Dyskerin binds the H/ACA box of human telomerase RNA and is a core telomerase subunit required for RNP biogenesis and enzyme function in vivo. Missense mutations in dyskerin result in dyskeratosis congenita, a complex syndrome characterized by bone marrow failure, telomerase enzyme deficiency, and ... ( view more )progressive telomere shortening. Here we demonstrate that dyskerin also contributes to telomere maintenance in Arabidopsis thaliana. We report that both AtNAP57, the Arabidopsis dyskerin homolog, and AtTERT, the telomerase catalytic subunit, accumulate in the plant nucleolus, and AtNAP57 associates with active telomerase RNP particles in an RNA-dependent manner. Furthermore, AtNAP57 interacts in vitro with AtPOT1a, a novel component of Arabidopsis telomerase. Although a null mutation in AtNAP57 is lethal, AtNAP57, like AtTERT, is not haploinsufficient for telomere maintenance in Arabidopsis. However, introduction of an AtNAP57 allele containing a T66A mutation decreased telomerase activity in vitro, disrupted telomere length regulation on individual chromosome ends in vivo, and established a new, shorter telomere length set point. These results imply that T66A NAP57 behaves as a dominant-negative inhibitor of telomerase. We conclude that dyskerin is a conserved component of the telomerase RNP complex in higher eukaryotes that is required for maximal enzyme activity in vivo. ( view less ) Sanya J Sanderson,Dong Xia,Helena Prieto,John Yates,Mark Heiges,Jessica C Kissinger,Elizabeth Bromley,Kalpana Lal,Robert E Sinden,Fiona Tomley,Jonathan M Wastling The genome of the intracellular parasite Cryptosporidium parvum has recently been sequenced, but protein expression data for the invasive stages of this important zoonotic gastrointestinal pathogen are limited. In this paper a comprehensive analysis of the expressed protein repertoire of an excyste... ( view more )d oocyst/sporozoite preparation of C. parvum is presented. Three independent proteome platforms were employed which yielded more than 4800 individual protein identifications representing 1237 nonredundant proteins, corresponding to approximately 30% of the predicted proteome. Peptide data were mapped to the corresponding locations on the C. parvum genome and a publicly accessible interface for proteome data was developed for data-mining and visualisation at CryptoDB (http://cryptodb.org). These data provide a timely and valuable resource for improved annotation of the genome, verification of predicted hypothetical proteins and identification of proteins not predicted by current gene models. The data indicated the expression of proteins likely to be important to the invasion and intracellular establishment of the parasite, including surface proteins, constituents of the remnant mitochondrion and apical organelles. Comparison of the expressed proteome with existing transcriptional data indicated only a weak correlation. For approximately half the proteome there was limited functional and structural information, highlighting the limitations in the current understanding of Cryptosporidium biology. ( view less ) R Edward Hendrick,Elodia B Cole,Etta D Pisano,Suddhasatta Acharyya,Helga Marques,Michael A Cohen,Roberta A Jong,Gordon E Mawdsley,Kalpana M Kanal,Carl J D'Orsi,Murray Rebner,Constantine Gatsonis PURPOSE: To retrospectively compare the accuracy for cancer diagnosis of digital mammography with soft-copy interpretation with that of screen-film mammography for each digital equipment manufacturer, by using results of biopsy and follow-up as the reference standard. MATERIALS AND METHODS: The pri... ( view more )mary HIPAA-compliant Digital Mammographic Imaging Screening Trial (DMIST) was approved by the institutional review board of each study site, and informed consent was obtained. The approvals and consent included use of data for future HIPAA-compliant retrospective research. The American College of Radiology Imaging Network DMIST collected screening mammography studies performed by using both digital and screen-film mammography in 49 528 women (mean age, 54.6 years; range, 19-92 years). Digital mammography systems from four manufacturers (Fischer, Fuji, GE, and Hologic) were used. For each digital manufacturer, a cancer-enriched reader set of women screened with both digital and screen-film mammography in DMIST was constructed. Each reader set contained all cancer-containing studies known for each digital manufacturer at the time of reader set selection, together with a subset of negative and benign studies. For each reader set, six or 12 experienced radiologists attended two randomly ordered reading sessions 6 weeks apart. Each radiologist identified suspicious findings and rated suspicion of breast cancer in identified lesions by using a seven-point scale. Results were analyzed according to digital manufacturer by using areas under the receiver operating characteristic curve (AUCs), sensitivity, and specificity for soft-copy digital and screen-film mammography. Results for Hologic digital are not presented owing to the fact that few cancer cases were available. The implemented design provided 80% power to detect average AUC differences of 0.09, 0.08, and 0.06 for Fischer, Fuji, and GE, respectively. RESULTS: No significant difference in AUC, sensitivity, or specificity was found between Fischer, Fuji, and GE soft-copy digital and screen-film mammography. Large reader variations occurred with each modality. CONCLUSION: No statistically significant differences were found between soft-copy digital and screen-film mammography for Fischer, Fuji, and GE digital mammography equipment. ( view less ) Sunil K Hota,Kalpana Barhwal,Shashi B Singh,M Sairam,Govindasamy Ilavazhagan Hypobaric hypoxia has been reported to cause memory dysfunction. The possible molecular mechanism involved, however, remains to be explored. The role that glutamate and its receptors play in causing excitotoxicity in ischemia and neurodegenerative diseases indicates the possible occurrence of a sim... ( view more )ilar phenomenon in hypobaric hypoxia. The present study aimed to elucidate the molecular events occurring at glutamatergic synapses in hypobaric hypoxia using Sprague-Dawley rats as a model system. The animals were exposed to an altitude of 7,600 m for different durations. Hypobaric hypoxia was found to cause oxidative stress, chromatin condensation, and neurodegeneration. A temporal change in the expression of the ionotropic receptors of glutamate was also observed. Expression of the N-methyl-D-aspartate (NMDA) receptor increased, and expression of glutamate receptor subunit 2 of the alpha-amino-3-hydroxy-5-methyl-4-isoxazoleproprionate receptor decreased. We also observed increased activity of glutamate dehydrogenase, indicating greater synthesis and release of glutamate after 3 and 7 days of exposure. Administration of a selective NMDA antagonist during exposure was found to ameliorate neuronal degeneration, providing evidence for the occurrence of excitotoxicity in hypobaric hypoxia. Our study indicates that excitotoxicity occurs in hypobaric hypoxia. This study also indicates the appropriate period for drug administration during exposure to hypobaric hypoxia and establishes ionotropic receptors of glutamate as potential therapeutic targets for ameliorating high-altitude-induced cognitive dysfunction. ( view less ) Lisa Dolovich,Kalpana Nair,Connie Sellors,Lynne Lohfeld,Annie Lee,Mitchell Levine OBJECTIVE: To investigate whether patients' expectations influence how they take their medications by looking at the expectations patients have of their medications and the factors that affect these expectations. DESIGN: Qualitative study using in-depth interviews and a grounded-theory approach. SE... ( view more )TTING: A large city in Ontario. PARTICIPANTS: A total of 18 community-dwelling adult patients taking medication for at least 6 months. METHOD: Both purposive and convenience sampling techniques were used. The initial strategy comprised stratified, maximum variation, and typical case sampling. The research team developed a semistructured interview guide after a preliminary review of the literature. Individual, face-to-face, in-depth interviews were conducted and audiotaped. At the end of the interviews, basic demographic information was collected. Interviewers were debriefed following each interview and their comments on relevant contextual information, general impressions of the interview, and possible changes to the interview guide were audiotaped. Audiotapes of each interview, including the debriefing, were transcribed verbatim, cleaned, and given a unique identifying number. At least 2 team members participated in analyzing the data using an operational code book that was modified to accommodate emerging themes as analysis continued. MAIN FINDINGS: Patients' expectations were more realistic than idealistic. Many participants acted on their expectations by changing their medication regimens on their own or by seeking additional information on their medications. Expectations were affected by patients' beliefs, past experiences with medications, relationships with their health care providers, other people's beliefs, and the cost of medication. Patients actively engaged in strategies to confirm or modify their expectations of their medications. CONCLUSION: A range of factors (most notably past experiences with medications and relationships with health care providers) influenced patients' expectations of their medications. More comprehensive discussion between patients and their health care providers about these factors could affect whether medications are used optimally. ( view less ) Gakuta Toba,Kalpana White ELAV is a neuron-specific RNA-binding protein in Drosophila that is required for development and maintenance of neurons. ELAV regulates alternative splicing of Neuroglian and erect wing (ewg) transcripts, and has been shown to form a multimeric complex on the last ewg intron. The protein has three ... ( view more )RNA recognition motifs (RRM1, 2 and 3) with a hinge region between RRM2 and 3. In this study, we used the yeast two-hybrid system to determine the multimerization domain of ELAV. Using deletion constructs, we mapped an interaction activity to a region containing most of RRM3. We found three conserved short sequences in RRM3 that were essential for the interaction, and also sufficient to give the interaction activity to RRM2 when introduced into it. In our in vivo functional assay, a mutation in one of the three sequences showed reduced activity in splicing regulation, underlining the functional importance of multimerization. However, RRM2 with the three RRM3 interaction sequences did not function as RRM3 in vivo, which suggested that multimerization is not the only function of RRM3. Our results are consistent with a model in which RRM3 serves as a bi-functional domain that interacts with both RNA and protein. ( view less )
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