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71.
Iron overload in paediatrics undergoing cardiopulmonary bypass 总被引:2,自引:0,他引:2
Mumby S Chaturvedi RR Brierley J Lincoln C Petros A Redington AN Gutteridge JM 《Biochimica et biophysica acta》2000,1500(3):342-348
Pathological changes in iron status are known to occur during bypass and will be superimposed upon physiological abnormalities in iron distribution, characteristic of the neonatal period. We have sought to define the severity of iron overload in these patients. Plasma samples from 65 paediatric patients undergoing cardiopulmonary bypass (CPB) were analysed for non-haem iron, total iron binding capacity, transferrin and bleomycin-detectable iron. Patients were divided into four age groups for analysis. Within each age group, patients who were in iron overload at any time point were statistically compared to those who were not. The most significant changes in iron chemistry were seen in the plasma of neonates, with 25% in a state of plasma iron overload. 18.5% of infants and 14.3% of children at 1-5 years were also in iron overload at some time point during CPB. No children over 5 years, however, went into iron overload. Increased iron saturation of transferrin eliminates its ability to bind reactive forms of iron and to act as an antioxidant. When transferrin is fully saturated with iron, reactive forms of iron are present in the plasma which can stimulate iron-driven oxidative reactions. Our data suggest that paediatric patients are at greater risk of iron overload during CPB, and that some form of iron chelation therapy may be advantageous to decrease oxidative stress. 相似文献
72.
D'Occhio MJ Sudha G Jillella D Whyte T Maclellan LJ Walsh J Trigg TE Miller D 《Theriogenology》1998,49(3):637-644
The synchrony of ovulation was examined in superstimulated heifers that had a downregulated pituitary gland and which were induced to ovulate by injection of exogenous LH. The pituitary was downregulated and desensitized to GnRH by treatment with the GnRH agonist deslorelin. Nulliparous heifers (3.5 yr old) at random stages of the estrous cycle were assigned to 1 of 3 groups, and on Day -7 received the following treatments: Group 1 (control, n = 8), 1 norgestomet ear implant; Group 2 (GnRH agonist, n = 8); Group 3 (GnRH agonist-LH protocol, n = 8), 2 deslorelin ear implants. Ovarian follicle growth in all heifers was superstimulated with twice-daily intramuscular injections of FSH (Folltropin-V): Day O, 40 mg (80 mg total dose); Day 1, 30 mg; Day 2; 20 mg; Day 3, 10 mg. On Day 2, all heifers were given a luteolytic dose of PGF (7 A.M.), Norgestomet implants were removed from heifers in Group 1 (6 P.M.). Heifers in Group 3 were given an injection of 25 mg, i.m. porcine LH (Lutropin) on Day 4 (4 P.M.). Ovarian follicle status was monitored at 8-h intervals from Day 3 (8 A.M.) to Day 6 (4 P.M.) using an Aloka Echo Camera and 7.5 MHz transducer. Heifers in Groups 2 and 3 exhibited estrus earlier (P < 0.05) than heifers in Group 1. Heifers in Group 2 did not have a preovulatory LH surge and they did not ovulate. Individual control heifers in Group 1 ovulated between 12 A.M. on Day 5 and 8 A.M. on Day 6. Heifers with deslorelin implants and injected with LH in Group 3 ovulated between 4 P.M. on Day 5 and 8 A.M. on Day 6. It was confirmed that superstimulated heifers with GnRH agonist implants can be induced to ovulate with LH. It was also demonstrated that ovulation is closely synchronized after injection of LH. Thus, a single, fixed-time insemination schedule could be used in a GnRH agonist-LH superovulation protocol, with significant practical and economic advantages for superovulation and embryo transfer programs. 相似文献
73.
74.
Palwinder Singh Jatinder Kaur Bhawna Yadav Sneha Sudha Komath 《Bioorganic & medicinal chemistry》2009,17(11):3973-3979
In order to search for MDR modulators, rationally designed acridone derivatives were investigated for their effect on influx or efflux of Rhodamine6G (R6G) in CAI4 cells. Results of these investigations indicate that in presence of compound 12, inhibition of growth of CAI4 cells and also an increased influx/efflux of R6G in CAI4 cells have been observed. This seems to be occurring due to the cell wall rupturing of Candida albicans. Compound 12 may be a suitable candidate for candidiasis therapy. 相似文献
75.
White-nose syndrome (WNS), an emerging disease of hibernating bats, has rapidly spread across eastern North America killing millions of bats. Pseudogymnoascus destructans (Pd), the sole etiologic agent of WNS, is widespread and persistent in bat hibernacula. Control of Pd in the affected sites is urgently needed to break the transmission cycle while minimizing any adverse impact on the native organisms. We isolated a novel strain of Trichoderma polysporum (Tp) from one of the caves at the epicenter of WNS zoonotic. Detailed experimental studies revealed: (1) Tp WPM 39143 was highly adapted to grow at temperatures simulating the cave environment (6°C-15°C), (2) Tp WPM 39143 restricted Pd colony growth in dual culture challenges, (3) Tp WPM 39143 caused four logs reduction of Pd colony forming units and genome copies in autoclaved soil samples from one of the WNS affected caves, (4) Tp WPM 39143 extract showed specific fungicidal activity against Pd in disk diffusion assay, but not against closely related fungus P. pannorum (Pp), (5) Tp WPM 39143 extract retained inhibitory activity after exposure to high temperatures, light and proteinase K, and (6) Inhibitory metabolites in Tp WPM 39143 extract comprised of water-soluble, high polarity compounds. These results suggest that Tp WPM 39143 is a promising candidate for further evaluation as a biocontrol agent of Pd in WNS affected sites. 相似文献
76.
Sumit Kumar Chaturvedi Nida Zaidi Parvez Alam Javed Masood Khan Atiyatul Qadeer Ibrar Ahmad Siddique Shamoon Asmat Yusra Zaidi Rizwan Hasan Khan 《PloS one》2015,10(8)
Amyloid fibril formation by proteins leads to variety of degenerative disorders called amyloidosis. While these disorders are topic of extensive research, effective treatments are still unavailable. Thus in present study, two anti-tuberculosis drugs, i.e., pyrazinamide (PYZ) and D-cycloserine (DCS), also known for treatment for Alzheimer’s dementia, were checked for the anti-aggregation and anti-amyloidogenic ability on Aβ-42 peptide and hen egg white lysozyme. Results demonstrated that both drugs inhibit the heat induced aggregation; however, PYZ was more potent and decelerated the nucleation phase as observed from various spectroscopic and microscopic techniques. Furthermore, pre-formed amyloid fibrils incubated with these drugs also increased the PC12/SH-SY5Y cell viability as compare to the amyloid fibrils alone; however, the increase was more pronounced for PYZ as confirmed by MTT assay. Additionally, molecular docking study suggested that the greater inhibitory potential of PYZ as compare to DCS may be due to strong binding affinity and more occupancy of hydrophobic patches of HEWL, which is known to form the core of the protein fibrils. 相似文献
77.
78.
Dev Chandran Kolli Bhaktavatsala Reddy Shahana Pallichera Vijayan Parthasarthy Sugumar Gudavalli Sudha Rani Ponsekaran Santha Kumar Lingala Rajendra Villuppanoor Alwar Srinivasan 《Indian journal of microbiology》2010,50(3):266-274
Peste des Petits Ruminants (PPR) is a highly contagious animal disease caused by the Peste des Petits Ruminants virus (PPRV) belonging to the genus morbillivirus and family Paramyxoviridae. The disease results in high morbidity and mortality
in goats, sheep and in some small wild ruminants. The presence of large number of small ruminants reared in endemic areas
makes PPR a notorious disease threatening the livelihood of poor farmers. Conventional vaccination using a live, attenuated
vaccine gives adequate protection but cannot be used in case of eradication of the disease due to difficulty in differentiation
of infected animals from the vaccinated ones. 相似文献
79.
Visvanathan S Rahman MU Keystone E Genovese M Klareskog L Hsia E Mack M Buchanan J Elashoff M Wagner C 《Arthritis research & therapy》2010,12(6):R211
Introduction
The goal of this study was to identify serum markers that are modulated by treatment with golimumab with or without methotrexate (MTX) and are associated with clinical response. 相似文献80.
Outbred mice traditionally are considered to display high variability, thereby limiting their use in some studies. Researchers frequently are encouraged to use inbred strains of mice because of the greater homogeneity of these experimental animals. We compared the pulmonary inflammatory response of inbred BALB/cJ mice to that of outbred HSD-ICR mice by measuring multiple variables, including cytokines, chemokines, number of pulmonary inflammatory cells, and respiratory parameters. Cockroach allergens induced significant pulmonary inflammation in both BALB and ICR mice. Our comparisons of the coefficients of variance for 148 discrete data sets for each strain or stock indicated that BALB and ICR mice have roughly equivalent intrastrain or -stock variability in our model of asthma-like pulmonary inflammation. The average coefficient of variance, calculated as the ratio of the SD to the mean of a data set, was 0.35 ± 0.34 for BALB mice compared with 0.31 ± 0.32 for ICR mice. In conclusion, inbred BALB and outbred ICR mice have roughly equivalent intrastrain or -stock variability in a murine model of asthma-like pulmonary inflammation. 相似文献