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31.
Sushmita Chakraborty Jakob Schneider Dipendra Kumar Mitra Katharina F. Kubatzky 《Immunology》2023,169(3):309-322
Interleukin (IL)-9 is an emerging player in the pathogenesis of various chronic inflammatory diseases including bone disorders like rheumatoid arthritis (RA) and psoriatic arthritis. Recently, IL-9 was shown to enhance the osteoclast formation and their function in RA. However, the mechanisms by which IL-9 influences osteoclastogenesis are not known. Therefore, in this study we aimed to unravel the direct and indirect ways by which IL-9 can influence osteoclast formation. We used mouse bone marrow precursor cells for checking the effect of IL-9 on osteoclast differentiation and its function. Next, IL-9 induced signalling pathway were checked in the process of osteoclastogenesis. T cells play an important role in enhancing osteoclastogenesis in inflammatory conditions. We used splenic T cells to understand the impact of IL-9 on the functions of T effector (Teff) and regulatory T (Treg) cells. Furthermore, the effect of IL-9 mediated modulation of the T cell response on osteoclasts was checked using a coculture model of T cells with osteoclast precursors. We showed that IL-9 enhanced osteoclast formation and its function. We found that IL-9 activates STAT3, P38 MAPK, ERK1/2, NFκB and we hypothesize that it mediates the effect on osteoclastogenesis by accelerating mitochondrial biogenesis. Additionally, IL-9 was observed to facilitate the functions of pro-osteoclastogenic IL-17 producing T cells, but inhibits the function of anti-osteoclastogenic Treg cells. Our observations suggest that IL-9 can influence osteoclastogenesis directly by modulating the signalling cascade in the precursor cells; indirectly by enhancing IL-17 producing T cells and by reducing the functions of Treg cells. 相似文献
32.
Pulak K. Chakraborty Thomas J. Mangner Diane C. Chugani Otto Muzik Harry T. Chugani 《Nuclear medicine and biology》1996,23(8):1005-1008
Alpha-[11C]methyl-l-tryptophan (AMT) has been synthesized by stereoselective methylation with [11C]methyl iodide of the lithium-enolate generated by treating dimethyl 2(S),3a(R),8a(S)-(+)-hexahydro-8(phenylsulfonyl) pyrrolo[2,3-b]indole-1,2-dicarboxylate (2) with lithium diisopropyl amide (LDA) at −55 °C, followed by ring opening using trifluoroacetic acid and alkaline hydrolysis of the protecting groups. The crude product was purified by a simple reverse-phase C-18 Sep-Pak procedure. The purified product was isolated with an average radiochemical yield of 53 ± 12% (decay corrected) in 30–35 min from [11C]methyl iodide. At end of synthesis (EOS), 138 ± 35 mCi (n = 24) of product was collected with a specific activity of ca. 1–1.3 Ci/μmol (EOS) (4–5 Ci/μmol @ EOB) starting from 1.5 Ci (EOB) of [11C]CO2. 相似文献
33.
Alphafetoprotein (AFP), an oncofetal antigen, plays very important roles in the early embryonic life and oncogenesis. Under various physiological and pathological conditions AFP exhibits microheterogeneity, probably as a result of differential expression of its epitopes. To analyse the epitopes we have developed a panel of monoclonal antibodies against human AFP purified by a new and efficient method using an immunoadsorbent consisting of polyclonal antibodies immobilized on cyanogen bromide activated Sepharose. Clones producing antibodies of various isotypes, e.g. IgG1, IgG2a, IgG2b, IgA and IgM have been subcloned and characterized. The antibodies showed high avidity for AFP (with half-maximal binding concentrations between 0.012 and 3.87 nM). Mutual inhibition efficiencies of a panel of 14 monoclonal antibodies were determined by RIA. Based on these inhibition data a computer program was used to group these antibodies with respect to their "epitope specificity distance". As a result of this grouping, clones have been identified which can recognize at least five different epitopes on AFP. This panel of antibodies may be very useful for analysis of the epitopic variation of AFP under various physiological and pathological conditions. 相似文献
34.
We report the case of a 13-year-old boy who presented with deafness due to a posterior fossa cystic lesion which was surgically excised. Histological examination showed it to be an enterogenous cyst. These extremely rare lesions seldom occur within the neural axis. 相似文献
35.
Dilip Rout Soumitra Mondal Indranil Chakraborty Malay Pramanik Syed Sirajul Islam 《Medicinal chemistry research》2004,13(6-7):509-517
The water-soluble glucan was obtained from Pleurotus florida fruit bodies by hot water extraction, ethanol precipitation, DEAE cellulose dialysis and Sephadex G-75 gel filtration. The
structural information of the glucan was achieved by chemical (hydrolysis, methylation, periodate oxidation) and spectroscopic
(1H and 13C) analyses, indicated a repeating unit built up of (1→6)-linked D-glucose. The following structure has been determined for
the repeating unit: →6)-α-D-Glcp-(1→ This fraction exhibited significant macrophage activity through the release of nitric
oxide 相似文献
36.
Taniya Sharma Nikita Kundu Sarvpreet Kaur Amlan Chakraborty Aman Kumar Mahto Rikeshwer Prasad Dewangan Jadala Shankaraswamy Sarika Saxena 《RSC advances》2022,12(34):21760
Research in recent decades has revealed that the guanine (G)-quadruplex secondary structure in DNA modulates a variety of cellular events that are mostly related to serious diseases. Systems capable of regulating DNA G-quadruplex structures would therefore be useful for the modulation of various cellular events to produce biological effects. A high specificity for recognition of telomeric G-quadruplex has been observed for BLM helicase. We identified peptides from the HRDC domain of BLM using a molecular docking approach with various available solutions and crystal structures of human telomeres and recently created a peptide library. Herein, we tested one peptide (BLM HRDC peptide) from the library and examined its interaction with human telomeric variant-1 (HTPu-var-1) to understand the basis of G4-protein interactions. Our circular dichroism (CD) data showed that HTPu-var-1 folded into an anti-parallel G-quadruplex, and the CD intensity significantly decreased upon increasing the peptide concentration. There was a significant decrease in hypochromicity due to the formation of G-quadruplex-peptide complex at 295 nm, which indicated the unfolding of structure due to the decrease in stacking interactions. The fluorescence data showed quenching upon titrating the peptide with HTPu-var-1-G4. Electrophoretic mobility shift assay confirmed the unfolding of the G4 structure. Cell viability was significantly reduced in the presence of the BLM peptide, with IC50 values of 10.71 μM and 11.83 μM after 72 and 96 hours, respectively. These results confirmed that the selected peptide has the ability to bind to human telomeric G-quadruplex and unfold it. This is the first report in which a peptide was identified from the HRDC domain of the BLM G4-binding protein for the exploration of the G4-binding motif, which suggests a novel strategy to target G4 using natural key peptide segments.Schematic representation of (HTPu–var-1-G4) located at the 3′ end, formation of G-quadruplex, model of the G-quadruplex structure, base stacking between G-quadruplex planes, G-quadruplex structure-peptide complex and twisting of G-quadruplex planes upon peptide binding. 相似文献
37.
Prithviraj Chakraborty Versha Parcha Debarupa D. Chakraborty Amitava Ghosh 《Drug delivery》2016,23(3):1016-1027
Objective: Buccoadhesive wafer dosage form containing Loratadine is formulated utilizing Formulation by Design (FbD) approach incorporating sodium alginate and lactose monohydrate as independent variable employing solvent casting method.Methods: The wafers were statistically optimized using Response Surface Methodology (RSM) and Artificial Neural Network algorithm (ANN) for predicting physicochemical and physico-mechanical properties of the wafers as responses. Morphologically wafers were tested using SEM. Quick disintegration of the samples was examined employing Optical Contact Angle (OCA).Results: The comparison of the predictability of RSM and ANN showed a high prognostic capacity of RSM model over ANN model in forecasting mechanical and physicochemical properties of the wafers. The in vivo assessment of the optimized buccoadhesive wafer exhibits marked increase in bioavailability justifying the administration of Loratadine through buccal route, bypassing hepatic first pass metabolism. 相似文献
38.
Ghosh S O'Hare F Lamoureux E Vajpayee RB Crowston JG 《Clinical & experimental ophthalmology》2012,40(7):675-681
Background: To determine the prevalence of signs and symptoms of ocular surface disease in two hospital‐based cohorts; glaucoma patients and non‐glaucoma patients. Design: A cross‐sectional, comparative case series. Participants: Glaucoma patients (n = 300) prescribed topical glaucoma medications for ≥6 months were compared with control patients (n = 100) who were not applying prescribed topical medications. Methods: A validated self‐report questionnaire was used to elicit the extent of ocular symptoms. Signs of ocular surface and eyelid disease were assessed along with medication history. Main Outcome Measures: Signs and symptoms of ocular surface pathology were determined including the tear film break‐up time, fluorescein staining of the cornea and conjunctiva, meibomian gland dysfunction and Schirmer's test. Results: A significant increase in the prevalence of ocular surface disease signs was observed in the glaucoma population, 70.3%, compared with controls, 33% (P < 0.001). The overall prevalence of clinically significant ocular surface disease symptoms was not significantly different between cohorts, 30.7% versus 24.0%, respectively (P = 0.252). Logistic regression analysis showed that the number of anti‐glaucoma medications and duration of therapy were key predictors of significant ocular surface disease signs in the glaucoma group. There was no significant correlation between signs and symptoms of ocular surface disease in either group after adjusting for age and gender. Conclusions: Signs and symptoms of ocular surface disease are relatively common in older patients, but signs of ocular surface disease are significantly higher in individuals who instil topical glaucoma therapy. 相似文献
39.
Tobacco carcinogen induces both lung cancer and non‐alcoholic steatohepatitis and hepatocellular carcinomas in ferrets which can be attenuated by lycopene supplementation 下载免费PDF全文
Koichi Aizawa Chun Liu Sanyuan Tang Sudipta Veeramachaneni Kang‐Quan Hu Donald E. Smith Xiang‐Dong Wang 《International journal of cancer. Journal international du cancer》2016,139(5):1171-1181
Early epidemiologic studies have reported that tobacco smoking, which is causally associated with liver cancer, is an independent risk factor for non‐alcoholic fatty liver diseases (NAFLD). Lycopene from tomatoes has been shown to be a potential preventive agent against NAFLD and hepatocellular carcinoma (HCC). In the present study, we investigated whether the tobacco carcinogen 4‐(N‐methyl‐N‐nitrosamino)‐1‐(3‐pyridyl)‐1‐butanone (NNK) induces lesions in both lungs and livers of ferrets with or without lycopene intervention. Male ferrets (6 groups, n = 8–10) were treated either with NNK (50 mg/kg BW, i.p., once a month for four consecutive months) or saline with or without dietary lycopene supplementation (2.2 and 6.6 mg/kg BW/day, respectively) for 26 weeks. Results demonstrate that NNK exposure results in higher incidences of lung tumors, HCC and steatohepatitis (which is characterized by severe inflammatory cell infiltration with concurrent fat accumulation in liver, hepatocellular ballooning degeneration and increased NF‐κB expression), as well as elevations in bilirubin and AST levels in ferrets. Lycopene supplementation at two doses prevented NNK‐induced expressions of α7 nicotinic acetylcholine receptor in the lung and NF‐κB and CYP2E1 in the liver and attenuated the NNK‐induced mortality and pathological lesions in both the lungs and livers of ferrets. The present study provided strong experimental evidence that the tobacco carcinogen NNK can induce both HCC and steatohepatitis in the ferrets and can be a useful model for studying tobacco carcinogen‐associated NAFLD and liver cancer. Furthermore, lycopene could provide potential benefits against smoke carcinogen‐induced pulmonary and hepatic injury. 相似文献
40.
In the past few decades, scientists have actively worked on developing effective drug delivery systems (DDSs) as means to control life-threatening diseases and challenging illnesses. In order to develop such DDSs, nanobiotechnological strategies have been introduced, and many nanomaterial-based DDS platforms have been proposed. Among these nanomaterials, DDSs based on exosomes and hybrids of exosomes have been focused upon and developed due to their low toxicity, high bioactivity, and biocompatibility. In this review, we describe the processes involved in drug loading into exosomes and the surface modification of exosomes with treatment agents. Furthermore, we describe the synthesis methods of hybrid exosomes with organic or inorganic nanoparticles. Moreover, we focus on the effective therapeutic applications of exosome-based DDSs against various diseases. In conclusion, we show that exosomes and hybrids of exosomes show excellent drug carrier potential and capacity.In the past few decades, scientists have actively worked on developing effective drug delivery systems (DDSs) as means to control life-threatening diseases and challenging illnesses. 相似文献