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61.
62.
Ravichandran Beerappa Dhananjayan Venugopal Somnath Sen Mala Ambikapathy Rajmohan Hirehal Raghavendra Rao 《International journal of occupational medicine and environmental health》2013,26(5):780-789
Objectives
The urinary excretion of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) was used as a biomarker of oxidative DNA damage. The urinary 8-oxodG levels in petrol filling station attendants (exposed) at various petrol bunks were estimated as well as in the unexposed (cashier) population.Materials and Methods
A total of 100 workers (79 petrol fillers and 21 cashiers) aged from 20 to 41 years participated in the study. An informed consent was taken from each participant. Information on personal habits and health was obtained through a questionnaire. After shifts, urine samples were collected analyzed for 8-oxodG using enzyme-linked immunosorbent assay (ELISA).Results
Fifty-three percent of workers were in the 21–30 years age group. The maximum level of 8-oxodG was observed in the age group ≥ 41 years and the minimum in the age group of 31–40 years. The maximum level of 8-oxodG was observed among those workers who had ≥ 21 years of experience. The concentrations of 8-oxodG were significantly higher in petrol fillers than those in cashiers (p < 0.05).Conclusions
Despite the conflicting results obtained in our study it was shown that 8-oxodG is related to chemical exposure. Further research is needed embracing a bigger number of participants to highlight the correlations between the exposure and the effects. 相似文献63.
Effect of vitamin E TPGS on immune response to nasally delivered diphtheria toxoid loaded poly(caprolactone) microparticles 总被引:4,自引:0,他引:4
Somavarapu S Pandit S Gradassi G Bandera M Ravichandran E Alpar OH 《International journal of pharmaceutics》2005,298(2):344-347
The nasal mucosa has many advantages as a potential site for drug and vaccine delivery. The present study has sought to exploit this route of delivery using microparticles composed of D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) as a matrix material blended with poly(caprolactone) for nasal immunisation with diphtheria toxoid. Particles were prepared by a double emulsion method, followed by spray drying and the effect of TPGS on size, zeta potential, loading and release of antigen was assessed. Particles composed of TPGS-PCL blends were spherical, smooth and monodisperse, displaying increasing yields after spray drying with increasing concentrations of TPGS. The immune response to diphtheria toxoid loaded PCL-TPGS microspheres after nasal administration was shown to be higher than that achieved using PCL microspheres alone. We conclude that TPGS shows significant potential as a novel adjuvant either alone or in combination with an appropriate delivery system. 相似文献
64.
S. K. Obendorf R. Sagan Kasunick V. Ravichandran J. Borsa C. W. Coffman 《Archives of environmental contamination and toxicology》1991,21(1):10-16
Because many pesticide handlers persist in wearing and reusing conventional workclothes, a renewable functional finish that enhances the pesticide-protective qualities of fabrics would be useful. This study investigated the ability of starch to act as a pesticide trap, preventing transfer and increasing removal by laundering, and the effect of carboxymethyl cellulose on release of pesticide in laundry. The retention and distribution of methyl parathion (MeP) on 65% polyester/35% cotton fabric was studied with four finishes: starch and carboxymethyl cellulose (CMC) as nondurable finishes; durable press resin (DP) and durable press/ carboxymethyl cellulose (DP/CMC) as durable finishes. Starching with an add-on of 8% (w/w) effectively reduced the area of contamination and enhanced the removal of methyl parathion from polyester/cotton fabrics. Residual pesticide values for CMC, DP, and DP/CMC finishes were similar to that of the unfinished fabric. While distribution profiles of methyl parathion throughout the yarn and fiber structures were similar for all the finishes, lower concentrations of pesticide were observed on the cotton fibers from the starched fabric. Starch reduced the pesticide transferring by rubbing from both 100% cotton and 65% polyester/cotton fabrics. These studies support the intriguing theory that starch can act as a pesticide trap on the fabric surface to decrease pesticide transfer and to enhance pesticide removal. Extensive penetration studies, field studies, and additional investigation of fiber, yarn, and fabric parameters are needed to further quantify the effects of starch. 相似文献
65.
Raman S Machaidze G Lustig A Aebi U Burkhard P 《Nanomedicine : nanotechnology, biology, and medicine》2006,2(2):95-102
Artificial particulate systems such as polymeric beads and liposomes are being applied in drug delivery, drug targeting, antigen display, vaccination, and other technologies. Here we used computer modeling to design a novel type of nanoparticles composed of peptides as building blocks. We verified the computer models via solid-phase peptide synthesis and biophysical analyses. We describe the structure-based design of a novel type of nanoparticles with regular polyhedral symmetry and a diameter of about 16 nm, which self-assembles from single polypeptide chains. Each peptide chain is composed of two coiled coil oligomerization domains with different oligomerization states joined by a short linker segment. In aqueous solution the peptides form nanoparticles of about 16 nm diameter. Such peptide nanoparticles are ideally suited for medical applications such as drug targeting and drug delivery systems, such as imaging devices, or they may be used for repetitive antigen display. 相似文献
66.
HIV associated systemic necrotizing vasculitis 总被引:2,自引:0,他引:2
The spectrum of HIV associated rheumatic syndromes continues to expand as does our experience with the disease. The following is a case of HIV associated systemic necrotizing vasculitis documented by rectal biopsy. The patient was treated successfully with corticosteroids alone, and after 9 months of followup has no evidence of progression to frank AIDS. 相似文献
67.
Decreased bioavailability of rifampin and other antituberculosis drugs in patients with advanced human immunodeficiency virus disease 下载免费PDF全文
Gurumurthy P Ramachandran G Hemanth Kumar AK Rajasekaran S Padmapriyadarsini C Swaminathan S Bhagavathy S Venkatesan P Sekar L Mahilmaran A Ravichandran N Paramesh P 《Antimicrobial agents and chemotherapy》2004,48(11):4473-4475
We evaluated the effects of human immunodeficiency virus (HIV) disease on pharmacokinetics of antituberculosis medications by measuring concentrations of isoniazid and rifampin in blood and of pyrazinamide and ethambutol in urine. Peak concentration and exposure were reduced for rifampin, and rapid acetylators of isoniazid had lower drug levels. HIV and HIV-tuberculosis patients who have diarrhea and cryptosporidial infection exhibit decreased bioavailability of antituberculosis drugs. 相似文献
68.
Upon sensing cytosolic double-stranded DNA (dsDNA), the murine Aim2 (encoded by the Aim2 gene) protein forms an inflammasome and promotes the secretion of proinflammatory cytokines, such as IL-1β and IL-18. In contrast, the p202 protein (encoded by the Ifi202 gene) does not form an inflammasome. Previously, we have reported that the interferon (IFN) and female sex hormone-induced increased nuclear levels of p202 protein in immune cells are associated with increased susceptibility to develop a lupus-like disease. However, signaling pathways that regulate the expression of Aim2 protein remain unknown. Here we report that the expression of Aim2 gene is induced in bone marrow-derived macrophages (BMDMs) by IFN-α treatment and the expression is, in part, STAT1-dependent. However, treatment of splenic T or B cells with IFN-α or their stimulation, which induced the expression of Ifi202 gene, did not induce the expression of Aim2 gene. Furthermore, treatment of cells with the male hormone androgen increased levels of Aim2 mRNA and protein. Moreover, treatment of murine macrophage cell lines (RAW264.7 and J774A.1) with IFN-α differentially induced the expression of Aim2 and p202 proteins and regulated their sub-cellular localization. Additionally, activation of Toll-like receptors (TLR3, 4, and 9) in BMDMs and cell lines also differentially regulated the expression of Aim2 and Ifi202 genes. Our observations demonstrate that cell type and gender-dependent factors differentially regulate the expression of the Aim2 and p202 proteins, thus, suggesting opposing roles for these two proteins in innate immune responses in lupus disease. 相似文献
69.
Senthilkumar Sadhasivam Anne Boat Mohamed Mahmoud 《Journal of clinical anesthesia》2009,21(7):493-501
Study ObjectiveTo evaluate the effect of dexmedetomidine as an adjunct to patient-controlled analgesia (PCA) with morphine.DesignRetrospective comparison.SettingUniversity-affiliated children's hospital.MeasurementsThe medical charts of 131 children with idiopathic scoliosis (IS) and NMS who had major spine surgery were reviewed. Out of 131, postoperatively 94 children received PCA with morphine alone (PCA group) and the remaining 37 children received PCA morphine and dexmedetomidine infusion at 0.4 mcg/kg/hour for 24 hours (PCA + Dex group). Preoperative, intraoperative, and postoperative morphine use data were collected.Main ResultsIntraoperative use of morphine was similar in children with IS and NMS. However, patients with IS used more morphine than patients with NMS on the first, second and third postoperative days in both groups. In children with IS, use of morphine on the second postoperative day was significantly higher in the PCA + Dex group (73 mg [50.5, 110.5]) than the PCA alone group (54 mg [36, 69], P = 0.03). The overall frequency of all perioperative complications was more in the PCA alone group (40% vs. 32%) than the PCA + Dex group.ConclusionPostoperative 24-hour dexmedetomidine infusion as an adjunct to PCA with opioids might have a morphine-sparing effect as evidenced by the increase in morphine use on postoperative day 2 after the dexmedetomidine infusion was stopped. 相似文献
70.