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1.
Fahad Ali Rahul Smita Jyoti Ambreen Fatima Saba Khanam Falaq Naz Yasir Hasan Siddique 《Scientia pharmaceutica》2016,84(2):361-377
The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats. 相似文献
2.
Mathematical Models for Predicting the Epidemiologic and Economic Impact of Vaccination against Human Papillomavirus Infection and Disease 总被引:2,自引:1,他引:1
Infection with human papillomavirus (HPV) is the primary causeof cervical cancer, other anogenital cancers, genital warts,and recurrent respiratory papillomatosis. Clinical studies havedemonstrated that a prophylactic HPV vaccine can prevent infection,genital warts, and the precancerous lesions that lead to cervicalcancer. Given the absence of data on the long-term effectivenessof HPV vaccination, a number of mathematical models have beendeveloped to provide insight to policy makers by projectingthe long-term epidemiologic and economic consequences of vaccinationand evaluate alternative vaccination policies. This paper reviewsthe state of these models. Three types of HPV mathematical modelshave been reported in the literature: cohort, population dynamic,and hybrid. All have demonstrated that vaccination can significantlyreduce the incidence of cervical cancer in the long term. However,only the cohort and hybrid models have evaluated the cost-effectivenessof vaccination strategies for preventing cervical cancer. Thesemodels have generally shown that vaccinating females can becost-effective. None has accounted for the potential benefitsof vaccinating the population to reduce the burden of recurrentrespiratory papillomatosis and cancers of the vagina, vulva,anus, penis, and head/neck. Given that only the population dynamicmodel can account for both the direct and indirect (i.e., herdimmunity effects) benefits of vaccination in the population,future research should focus on further development of dynamicmodels by expanding the range of epidemiologic outcomes trackedand including the ability to assess the cost-effectiveness ofalternative vaccination policies. cost-benefit analysis economics papillomavirus, human vaccines 相似文献
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4.
S R Adair D Elamin S Tharmaratnam 《The journal of maternal-fetal & neonatal medicine》2004,15(4):275-278
Placenta increta, a rare complication of pregnancy, is associated with significant postpartum hemorrhage often requiring emergency hysterectomy. We report a case of conservative management, with a combination of parenteral methotrexate, serial ultrasound and Doppler assessment, followed by interval manual removal of placenta. 相似文献
5.
Cloning and characterization of a gene encoding an immunoglobulin-binding receptor on the cell surface of some members of the family Trypanosomatidae 下载免费PDF全文
Campos-Neto A Suffia I Cavassani KA Jen S Greeson K Ovendale P Silva JS Reed SG Skeiky YA 《Infection and immunity》2003,71(9):5065-5076
Several members of the Trypanosomatidae family, when freshly isolated from their mammalian hosts, have immunoglobulins adsorbed to their cell surfaces. However, a significant portion of these antibody molecules is not parasite specific, i.e., the immunoglobulins are bound to the parasite's cell surface molecules via noncognitive interactions. It has been proposed that this noncognitive adsorption of immunoglobulins to the parasite is mediated by an Fc-like receptor present in several members of the Trypanosomatidae family. However, the molecular identification of this receptor has never been defined. Here, we describe the cloning of a gene encoding a protein that might represent this molecule. The gene, named Lmsp1, was cloned by screening a Leishmania major cDNA expression library using a rabbit antiserum. Lmsp1 is present in both Leishmania and Trypanosoma and is expressed in all developmental stages of these parasites. The predicted protein has a molecular mass of 16.6 kDa and contains an RGD sequence starting at residue 104 and three cysteine residues at positions 55, 74, and 116. The purified recombinant protein strongly binds to normal immunoglobulins of various animal species (humans, rabbits, sheep, goats, guinea pigs, donkeys, rats, and mice) and the binding to human immunoglobulins appears to be immunoglobulin G (IgG) and IgM isotype specific. Moreover, Lmsp1 binds to both purified Fc and Fab fragments of IgG from both humans and rabbits. The mapping of the Lmsp1 epitopes that bind human IgG revealed that different sequences of the molecule bind to Fc or Fab. In addition, fluorescence-activated cell sorter analyses with a specific rabbit anti-Lmsp1 antiserum showed that Lmsp1 is associated with the parasite's cell surface. Finally, inhibition experiments point to an active role of this molecule in the immunoglobulin-mediated attachment and penetration of Trypanosoma cruzi in its macrophage host cells, thus suggesting that Lmsp1 is a putative Trypanosomatidae immunoglobulin receptor. 相似文献
6.
Use of multiepitope polyproteins in serodiagnosis of active tuberculosis 总被引:13,自引:0,他引:13
Houghton RL Lodes MJ Dillon DC Reynolds LD Day CH McNeill PD Hendrickson RC Skeiky YA Sampaio DP Badaro R Lyashchenko KP Reed SG 《Clinical and diagnostic laboratory immunology》2002,9(4):883-891
Screening of genomic expression libraries from Mycobacterium tuberculosis with sera from tuberculosis (TB) patients or rabbit antiserum to M. tuberculosis led to the identification of novel antigens capable of detecting specific antibodies to M. tuberculosis. Three antigens, Mtb11 (also known as CFP-10), Mtb8, and Mtb48, were tested together with the previously reported 38-kDa protein, in an enzyme-linked immunosorbent assay (ELISA) to detect antibodies in TB patients. These four proteins were also produced as a genetically fused polyprotein, which was tested with two additional antigens, DPEP (also known as MPT32) and Mtb81. Sera from individuals with pulmonary and extrapulmonary TB, human immunodeficiency virus (HIV)-TB coinfections, and purified protein derivative (PPD)-positive and PPD-negative status with no evidence of disease were tested. In samples from HIV-negative individuals, the ELISA detected antibodies in >80% of smear-positive individuals and >60% smear-negative individuals, with a specificity of approximately 98%. For this group, smears detected 81.6% but a combination of smear and ELISA had a sensitivity of approximately 93%. The antigen combination detected a significant number of HIV-TB coinfections as well as antibodies in patients with extrapulmonary infections. Improved reactivity in the HIV-TB group was observed by including the antigen Mtb81 that was identified by proteomics. The data indicate that the use of multiple antigens, some of which are in a single polyprotein, can be used to facilitate the development of a highly sensitive test for M. tuberculosis antibody detection. 相似文献
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8.
Iqra Jabbar Yasir Zaman Khaled Althubeiti Sattam Al Otaibi M. Zahid Ishaque Nasir Rahman Mohammad Sohail Alamzeb Khan Asad Ullah Tommaso Del Rosso Quaid Zaman Rajwali Khan Aurangzeb Khan 《RSC advances》2022,12(21):13456
The hydrothermal method was used to create dilute magnetic semiconductor nanoparticles of Zn1−xCoxO (x = 0, 0.01, 0.05, 0.09). The effect of cobalt doping on the microstructure, morphological and optical properties of Zn1−xCoxO was also studied and the Co doping to host ZnO was confirmed from XRD and EDX analysis. The structural analysis showed that doping of cobalt into ZnO decreased the crystallinity, but the preferred orientation didn''t change. SEM analysis revealed that the cobalt dopant did not have a strong influence on the shape of the synthesized nanoparticles. No defect-related absorption peaks were observed in the UV-Vis spectra. The crystallinity of the doped samples was improved by high growth temperature and long growth time. Ferromagnetic behavior above room temperature was detected in co-doped ZnO nanoparticles. The ferromagnetic behavior increased with increasing Co (up to x = 0.05) doping. The ferromagnetic behavior declined when the Co content was further increased. Related research shows that doped ZnO nanoparticles have better dielectric, electrical conductivity, and magnetic properties than pure ZnO. This high ferromagnetism is usually a response reported for dilute magnetic semiconductors. These semiconductor nanoparticles were further used to designed spintronic based applications.The enlarged central part M–H loop shows for the Co = 0.09 doped ZnO sample, the ferromagnetic (FM) behavior increased, i.e., a Mr of 0.2412 emu g−1 with a Hc of 85 Oe. 相似文献
9.
Faisal K. Algethami Khaled Trabelsi Anouar Hajjaji Mohamed B. Rabha Lotfi Khezami Mohamed R. Elamin Brahim Bessais My Ali El Khakani 《Materials》2022,15(14)
The present work aims to study the photocatalytic properties of nanohybrids composed of silicon nanowires (SiNWs) decorated with PbS nanoparticles (NPs). The elaborated material was intended to be utilized in wastewater treatment. The SiNWs were elaborated from the Metal Assisted Chemical Etching route (MACE), while the PbS NPs were deposited at room temperature onto SiNWs using the pulsed laser deposition (PLD) technique. The influence of decorating SiNWs (having different lengths) with PbS-NPs on their structural, morphological, optoelectronic, and photocatalytic properties was scrutinized. PbS/SiNWs nanohybrids exhibited enhanced photocatalytic degradation towards Black Amido (BA) dye for 20 µm SiNWs length and 0.2% of BA volume concentration. These optimized conditions may insinuate that this nanocomposite-like structure is a promising efficient photocatalytic systems contender, cost-effective, and recyclable for organic compound purification from wastewaters. 相似文献
10.
Izaz Ahmad Mudasir Iqbal Asim Abbas Yasir Irfan Badrashi Arshad Jamal Shahid Ullah Ahmed M. Yosri Moustafa Hamad 《Materials》2022,15(9)
Steel fibers are widely extracted from scrap tyres, causing environmental concerns. This paper presents the use of steel fibers in variable proportions extracted from scrap tyres. The enhancement of the confinement was envisaged through the addition of steel fibers obtained from scrap tyres. The study included an experimental program for the development of constitutive material models for ordinary Portland cement (OPC) concrete and concrete with added steel fibers. A mix design was carried out for OPC, targeting a compressive strength of 3000 psi. Steel fibers were added to OPC in ratios of 1.0% to 3.0%, with an increment of 0.5%. Concrete columns, with cross-sectional dimensions of 6 × 6 inches and a length of 30 inches, were cast with both OPC and fiber-reinforced concrete. The column confinement was evaluated with a different spacing of ties (3- and 4-inch center-to-center). Compression tests on the concrete columns indicate that the addition of steel fibers to a concrete matrix results in an appreciable increase in strength and ductility. Overall, increasing the percentage of steel fibers increased the compression strength and the ductility of concrete. The maximum strain in the concrete containing 2.5% steel fibers increased by 285% as compared to the concrete containing 1% of steel fibers. An optimum percentage of 2.5% steel fibers added to the concrete resulted in a 39% increase in compressive strength, accompanied by a significant improvement in ductility. The optimum content of steel fibers, when used in confined columns, showed that confined compression strength increased with the addition of steel fibers. However, it is recommended that additional columns on the basis of the optimum steel fiber content shall be tested to evaluate their effectiveness in reducing the stirrup spacing. 相似文献