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Teng D, Lu Y, Gao R, Xin Y, Cao G, Li X, Wang L, Wang J, Wang L, Li Y. Conversion from cyclosporine to mycophenolate mofetil improves expression of A20 in the rat kidney allografts undergoing chronic rejection. Transplant Proc 2006; 38:2164-7. [PMID: 16980032 DOI: 10.1016/j.transproceed.2006.06.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
AIMS Cytoprotective genes have shown to display potent anti-inflammatory and antiapoptotic functions in endothelial and smooth muscle cells. We investigated whether cytoprotective genes, especially A20, were involved in mycophenolate mofetil (MMF)'s ability to ameliorate transplant arteriosclerosis in an experimental chronic rejection model. METHODS Sprague-Dawley rat renal grafts were orthotopically transplanted into Wistar rats following the procedure of Kamada with our modification. The recipients were divided into three oral treatment groups: (1) vehicle group (cyclosporine [CsA] 10 mg/kg.d x 10 d followed by vehicle), (2) CsA group (CsA 10 mg/kg.d x 10 d followed by CsA 6 mg/kg.d), (3) MMF group (converted from CsA 10 mg/kg.d x 10 d to MMF 20 mg/kg.d on day 11). At the same time points after transplantation, the rats were sacrificed to harvest the renal allografts. The expression of four cytoprotective genes, A20, heme oxygenase (HO)-1, Bcl-2, and Bcl-XL, was analyzed by quantitative reverse-transcriptase polymerase chain reaction and immunohistochemistry. RESULTS The four-cytoprotective genes were all detected in rat kidney allografts undergoing chronic allograft nephropathy. The expression of A20 in grafted kidneys was significantly higher in the MMF than in the CsA or the vehicle group (P < .01). There was no significant difference between the CsA and the MMF groups in the expression of HO-1, Bcl-2, and Bcl-XL. CONCLUSIONS We demonstrated that MMF improved the expression of A20 in rat kidney allografts undergoing chronic allograft nephropathy. The correlation between MMF and A20 provide an explanation for the mechanism by which MMF ameliorates transplant arteriosclerosis in an experimental animal model of chronic rejection.
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Cao G, Lu Y, Gao R, Xin Y, Teng D, Wang J, Li Y. Expression of fractalkine, CX3CR1, and vascular endothelial growth factor in human chronic renal allograft rejection. Transplant Proc 2006; 38:1998-2000. [PMID: 16979977 DOI: 10.1016/j.transproceed.2006.06.081] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
AIM Fractalkine/CX3CR1 system may contribute to the pathogenesis of renal allograft chronic rejection (CR). Vascular endothelial growth factor (VEGF) is an endothelial mitogen, which shows increased expression in inflammation and vasculopathy. This study sought describe the expression and distribution of Fractalkine/CX3CR1 and VEGF, and their relationship to human renal allograft CR. METHODS Renal tissue from 10 patients with CR was examined for Fractalkine/CX3CR1 and VEGF protein by immunohistochemistry for comparison with patients displaying hyperacute rejection (n = 10), acute rejection (n = 10), and normal kidneys (n = 10). All patients were selected based upon histologically proven diagnoses between 1992 and 2003. RESULTS Immunohistochemistry revealed that Fractalkine/CX3CR1 were mostly expressed in the tubulointerstitium and tubular epithelial cell basolateral membrane. Some vessels showed positive staining for Fractalkine/CX3CR1 as well as occasionally glomerular parietal wall cells. Among the CR group, VEGF was mostly expressed in tubular epithelium and the tubulointerstitium. A proportion of glomeruli and vessels had positive staining for VEGF, which was up-regulated most strikingly in the interstitial compartment in CR. There was markedly increased expression of Fractalkine/CX3CR1 and VEGF protein in the interstitium of the CR compared with other groups (P < .05). VEGF colocalized with the expression of Fractalkine/CX3CR1. CONCLUSION Fractalkine/CX3CR1 and VEGF may play an important role in the development of interstitial fibrosis via mononuclear cell-induced cytokine production and myofibroblast stimulation in CR. Further studies are necessary to identify the role in the pathogenesis of CR.
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Cao G, Lu Y, Gao R, Xin Y, Teng D, Wang J, Wang L, Li Y. Comparison of cyclosporine versus mycophenolate mofetil on expression of Fractalkine and CX3CR1 in chronic allograft nephropathy. Transplant Proc 2006; 38:2234-6. [PMID: 16980051 DOI: 10.1016/j.transproceed.2006.06.046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
INTRODUCTION We sought to investigate whether there was a difference between cyclosporine (CsA) and mycophenolate mofetil (MMF) to affect the expression of Fractalkine/CX3CR1 in chronic allograft nephropathy (CAN). METHODS The Sprague-Dawley Wistar rat accelerated kidney sclerosis model was performed as modified from the procedure of Kamada. Recipients were divided into three oral treatment groups (each group n = 8): group A was CsA 10 mg/kg . d for 10 days followed by vehicle; group B was CsA 10 mg/kg . d for 10 days followed by CsA 6 mg/kg.d; group C was CsA 10 mg/kg . d for 10 days followed by MMF 20 mg/kg . d. Pathological changes graded according to Banff 97 Standards were observed at 4, 8, and 12 weeks posttransplantation. The immunohistochemistry and quantitative real-time fluorescence polymerase chain reaction (PCR) were used to assess the distribution and expression of Fractalkine/CX3CR1 in the grafted kidney. RESULTS Fractalkine/CX3CR1 were mostly expressed in the tubulointerstitium and tubular epithelial cell basolateral membrane. A proportion of the vessel showed positive staining for Fractalkine/CX3CR1, occasionally in glomerular parietal wall cells. The expression of Fractalkine/CX3CR1 in grafted kidneys at all the time points was significantly less in the MMF than in the CsA group or the control group (P < .05). Real-time fluorescence quantitative PCR revealed similar outcomes as immunohistochemistry. The expression of Fractalkine coincided with CX3CR1. CONCLUSION Fractalkine/CX3CR1 may play an important role in the development of interstitial fibrosis in CAN. Different immunosuppressants have various effects on expression of the Fractalkine/CX3CR1.
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Teng D, Lu Y, Gao R, Xin Y, Cao G, Li X, Wang L, Wang J, Li Y. Comparison of rapamycin versus FK506 on expression of cytoprotective genes in the rat kidney allografts undergoing chronic allograft nephropathy. Transplant Proc 2006; 38:2172-5. [PMID: 16980034 DOI: 10.1016/j.transproceed.2006.06.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
AIMS It is increasingly recognized that expression of cytoprotective genes in grafts can affect the progress of chronic allograft nephropathy (CAN). Little is known about the influence of different immunosuppressive regimens on expression of cytoprotective genes in allografts undergoing CAN. We investigate whether there is difference between rapamycin (Rapa) and FK506 in the expression of cytoprotective genes in rat kidney allografts undergoing CAN. METHODS Sprague-Dawley rat renal grafts were orthotopically transplanted into Wistar rats following the procedure of Kamada with our modification. The recipients were divided into three oral treatment groups: group 1: vehicle group (cyclosporine [CsA] 10 mg/kg.dx 10 days followed by vehicle); group 2: Rapa group (CsA 10 mg/kg.d x 10 d followed by Rapa 0.8 mg/kg.d); group 3: FK506 group (CsA 10 mg/kg.d x 10 d followed by FK506 0.15 mg/kg.d). At the same times after transplantation, the rats were sacrificed to harvest the renal allografts. The expression of four cytoprotective genes, A20, heme oxygenase (HO)-1, Bcl-2, and Bcl-X/L were analyzed in these grafted kidneys by quantitative reverse transcriptase polymerase chain reaction and immunohistochemistry. RESULTS Four cytoprotective genes were all detected in rat kidney allografts undergoing CAN. The expression of A20 in the Rapa group was significantly higher than that in the FK506 or the vehicle group (P < .05). There was no significant difference between the Rapa group and FK506 group in the expressions of HO-1, Bcl-2, and Bcl-X/L. CONCLUSIONS We demonstrate that various immunosuppressive agents have different effects on the expression of cytoprotective genes.
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Rosón MI, Cavallero S, Della Penna S, Cao G, Gorzalczany S, Pandolfo M, Kuprewicz A, Canessa O, Toblli JE, Fernández BE. Acute sodium overload produces renal tubulointerstitial inflammation in normal rats. Kidney Int 2006; 70:1439-46. [PMID: 16955102 DOI: 10.1038/sj.ki.5001831] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The aim of the present study was to determine whether acute sodium overload could trigger an inflammatory reaction in the tubulointerstitial (TI) compartment in normal rats. Four groups of Sprague-Dawley rats received increasing NaCl concentrations by intravenous infusion. Control (C): Na+ 0.15 M; G1: Na+ 0.5 M; G2: Na+ 1.0 M; and G3: Na+ 1.5 M. Creatinine clearance, mean arterial pressure (MAP), renal blood flow (RBF), and sodium fractional excretion were determined. Transforming growth factor beta1 (TGF-beta1), alpha-smooth muscle actin (alpha-SMA), RANTES, transcription factor nuclear factor-kappa B (NF-kappaB), and angiotensin II (ANG II) were evaluated in kidneys by immunohistochemistry. Animals with NaCl overload showed normal glomerular function without MAP and RBF modifications and exhibited a concentration-dependent natriuretic response. Plasmatic sodium increased in G2 (P < 0.01) and G3 (P < 0.001). Light microscopy did not show renal morphological damage. Immunohistochemistry revealed an increased number of ANG II-positive tubular cells in G2 and G3, and positive immunostaining for NF-kappaB only in G3 (P < 0.01). Increased staining of alpha-SMA in the interstitium (P < 0.01), TGF-beta1 in tubular cells (P < 0.01), and a significant percentage (P < 0.01) of positive immunostaining for RANTES in tubular epithelium and in glomerular and peritubular endothelium were detected in G3 > G2 > C group. These results suggest that an acute sodium overload is able 'per se' to initiate TI endothelial inflammatory reaction (glomerular and peritubular) and incipient fibrosis in normal rats, independently of hemodynamic modifications. Furthermore, these findings are consistent with the possibility that activation of NF-kappaB and local ANG II may be involved in the pathway of this inflammatory process.
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Dickover B, Durazo R, Cao G, Luke A, Cooper R. Chronic Obstructive Pulmonary Disease, Body Mass Index, and Mortality in a National Representative Sample. Am J Epidemiol 2006. [DOI: 10.1093/aje/163.suppl_11.s23-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Durazo-Arvizu R, Luke A, Cao G, Cooper RS. Hypertension in Mexico and Among Mexican Americans: Prevalence, Risk Factors, and Treatment Patterns. S Barquera. Am J Epidemiol 2006. [DOI: 10.1093/aje/163.suppl_11.s11-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Zhu Y, Si J, Harn DA, Xu M, Ren J, Yu C, Liang Y, Yin X, He W, Cao G. Schistosoma japonicum triose-phosphate isomerase plasmid DNA vaccine protects pigs against challenge infection. Parasitology 2006; 132:67-71. [PMID: 16393355 DOI: 10.1017/s0031182005008644] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2005] [Revised: 06/22/2005] [Accepted: 06/22/2005] [Indexed: 11/06/2022]
Abstract
The protective efficacy of a Schistosoma japonicum, Chinese strain, triose-phosphate isomerase (TPI) plasmid DNA vaccine was examined in naïve pigs. Pigs were vaccinated with the TPI DNA-plasmid alone, or in conjunction with IL-12 as pcDNA3.1-P35, pcDNA3.1-P40 plasmids via intramuscular injection. Control pigs were immunized with equivalent amounts of pcDNA3.1. Pigs were immunized 3 times at 21-day intervals and challenged 30 days after the final boost. Forty-five days post-challenge, pigs were sacrificed and perfused to compare adult worm burdens, female worm burdens, liver egg burdens and granuloma size. We found that pigs vaccinated with SjCTPI DNA alone had adult worm burdens reduced by 48.3% and that a further decrease in adult worm burdens was not seen in the group vaccinated with SjCTPI DNA in conjunction with IL-12 (46.2% reduction). The SjCTPI DNA vaccines had a more pronounced effect on reducing female worm burdens i.e. 53.6% SjCTPI alone and 59.6% for SjCTPI+IL-12. Vaccination with SjCTPI-DNA reduced liver eggs by 49.4% and this response was significantly enhanced by the addition of IL-12 (65.8% reduction in liver eggs). In addition to the dramatic protective effects seen in vaccinated pigs, we also noted that granuloma size was reduced by 42% in both groups. Thus, vaccination of pigs and other large animals in China with SjCTPI DNA vaccine will likely reduce transmission by reducing adult worm burdens and worm egg output and simultaneously reduce hepatic egg-associated pathology.
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Caschili S, Delogu F, Concas A, Pisu M, Cao G. Mechanically induced self-propagating reactions: analysis of reactive substrates and degradation of aromatic sulfonic pollutants. CHEMOSPHERE 2006; 63:987-95. [PMID: 16310824 DOI: 10.1016/j.chemosphere.2005.08.052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2005] [Revised: 08/23/2005] [Accepted: 08/24/2005] [Indexed: 05/05/2023]
Abstract
Mechanochemical reactions have been identified as a valuable alternative to conventional methodologies for the degradation of toxic pollutants as well as for their abatement in contaminated matrices. This paper discusses the application of the mechanochemical technique to the degradation of sulfonic acids in a contaminated matrix. The degradation of the pollutant compound was carried out by taking advantage of combustive reactions on a suitable reactive system ignited under mechanical treatment conditions. Two systems have been investigated as possible reactive substrates. The first one was a Mg-SiO2 powder mixture while the second system was a Ca-SiO2 powder mixture. Milling trials performed under different mechanical processing conditions allowed one to characterise the reactivity of these chemical systems, which basically undergo a reduction/oxidation reaction involving the formation of MgO and Si phases when the Mg-SiO2 system is considered and CaO and Si phases when the Ca-SiO2 system is employed, respectively. The systematic change of the stoichiometric ratios Mg:SiO2 and Ca:SiO2 permitted to identify the minimum Mg or Ca content necessary for the ignition of the combustive reactions. The experimental runs performed with such systems have shown a greater effectiveness of the Mg-SiO2 because of less energy inputs required to ignite a combustion. For this reason the Mg-SiO2 has been considered as a reactive substrate in the following trials. Since the SiO2 amount in stoichiometric excess may be regarded as inert phase, it was substituted with a different phase consisting of the matrix contaminated by sulfonic acids. This aspect permitted to ignite a combustive reaction with the minimum possible content of Mg-SiO2 reacting mixture. The chemical analyses performed after the combustive reaction proved the complete removal of the sulfonic acid from the contaminated matrix.
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Concas A, Ardau C, Cristini A, Zuddas P, Cao G. Mobility of heavy metals from tailings to stream waters in a mining activity contaminated site. CHEMOSPHERE 2006; 63:244-53. [PMID: 16216301 DOI: 10.1016/j.chemosphere.2005.08.024] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2005] [Revised: 07/27/2005] [Accepted: 08/06/2005] [Indexed: 05/04/2023]
Abstract
In this paper the results of a recent characterization of Rio Piscinas (SW of Sardinia, Italy) hydrological basin are reported. In such area (about 50 km2), previous mining activities caused a serious heavy metal contamination of surface waters, groundwater, soils and biota. Acid mine drainage phenomena were observed in the area. The main sources of contamination are the tailings stored in mine tunnels and abandoned along fluvial banks. A methodological approach was adopted in order to identify relations between tailings and water contamination. Representative samples of tailings and stream sediments samples were collected. XRD analyses were performed for mineralogical characterization, while acid digestion was carried out for determining metal contents. Batch sequential leaching tests were performed in order to assess metal mobility. Also groundwater and stream water were sampled in specific locations and suitably characterized. All information collected allowed the understanding of the effect of tailings on water contamination, thus contributing to the qualitative prediction of pollution evolution on the basis of metal mobility. Finally, a potential remediation strategy of stream water is proposed.
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Gupta R, Kim M, Barath H, Cooper SL, Cao G. Field- and pressure-induced phases in Sr4Ru3O10: a spectroscopic investigation. PHYSICAL REVIEW LETTERS 2006; 96:067004. [PMID: 16606035 DOI: 10.1103/physrevlett.96.067004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2005] [Indexed: 05/08/2023]
Abstract
We have investigated the magnetic-field- and pressure-induced structural and magnetic phases of the triple-layer ruthenate Sr4Ru3O10. Magnetic-field-induced changes in the phonon spectra reveal dramatic spin-reorientation transitions and strong magnetoelastic coupling in this material. Further, we are able to deduce key magnetoelastic coupling parameters, and evidence that the magnetic moments are localized on the Ru sites. Additionally, pressure-dependent Raman measurements at different temperatures reveal an anomalous negative Gruneisen parameter associated with the B(1g) mode (approximately 380 cm(-1)) at low temperatures (T < 75 K), which can be explained consistently with the field-dependent Raman data.
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Locci AM, Orrù R, Cao G, Sanna S, Congiu F, Concas G. Synthesis of bulk MgB2 superconductors by pulsed electric current. AIChE J 2006. [DOI: 10.1002/aic.10846] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Locci AM, Licheri R, Orrù R, Cincotti A, Cao G, De Wilde J, Lemoisson F, Froyen L, Beloki IA, Sytschev AE, Rogachev AS, Jarvis DJ. Low-gravity combustion synthesis: Theoretical analysis of experimental evidences. AIChE J 2006. [DOI: 10.1002/aic.11006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Wang Y, Cheung PT, Shen GX, Wu EX, Cao G, Bart I, Wong WHS, Khong PL. Hypoxic-ischemic brain injury in the neonatal rat model: relationship between lesion size at early MR imaging and irreversible infarction. AJNR Am J Neuroradiol 2006; 27:51-4. [PMID: 16418355 PMCID: PMC7976102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
BACKGROUND AND PURPOSE By using a neonatal rat hypoxia-ischemia (HI) model, we studied the relationship between lesion volume-measured by diffusion-weighted imaging (DWI) and T2-weighted imaging (T2WI) at an early time point-and irreversible infarct volume. We also evaluated the optimal apparent diffusion coefficient (ADC) threshold that provides the best correlation with irreversible infarct size. MATERIALS AND METHODS Twenty-three neonatal rats underwent right common carotid artery ligation and hypoxia. MR imaging was performed 1-2 hours post-HI by using DWI and T2WI and at day 4 post-HI by using T2WI. Lesion volumes relative to whole brain (%LV) were measured on ADC maps by using different relative ADC thresholds 60%-80% of mean contralateral ADC and T2WI. Pearson correlation and multiple linear regression analysis were used to study the relationships between ln(%LV) at MR imaging and %LV at histopathology. RESULTS At 1-2 hours post-HI, all lesion volume measurements on DWI were significantly correlated with the infarct volume on histopathology, with the best correlation attained at the 80% ADC threshold (r = 0.738; P < .001). The estimated regression formula was %LV on histopathology = 20.60 + 3.33 ln(%LV on 80% ADC threshold) (adjusted R(2) = 0.523; P < .001). Lesion volume at 1-2 hours post-HI tended to underestimate the final infarct volume. CONCLUSION Early post-HI MR imaging by using DWI correlates moderately well with the size of irreversible infarct, especially when measured by using a relative ADC threshold of 80% mean contralateral ADC.
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Muray S, Marco MP, Carrera I, Cao G, Craver L, Fernández E. Relative hypoparathyroidism induced by interferon treatment in a hemodialysis patient. Clin Nephrol 2005; 64:163-6. [PMID: 16114795 DOI: 10.5414/cnp64163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Several authors have documented beneficial effects of interferon (IFN) in chronic hepatitis C virus (HCV) infection among the dialysis population. Reports about mineral metabolism disturbances during IFN treatment are scarce, especially in dialysis patients. We report the case of a 49-year-old woman on hemodialysis with chronic HCV infection who developed significant decrease in serum calcium (Ca) and phosphorus (P) levels accompanied by relative hypoparathyroidism while being under treatment with alpha-IFN. These changes were closely related to IFN treatment, because they disappeared after INF was discontinued, reaching Ca and P levels which were similar to those of the pre-IFN period. Because IFN may induce immune disorders, several autoimmune markers were analyzed. All of them were negative or within the normal range. To further explore these mineral metabolism disturbances, a number ofparathyroid hormone (PTH) secretion-inhibiting factors, such as aluminum, magnesium, 25-hydroxyvitamin D, and calcitriol were excluded as a cause for these changes. We suggest that mineral metabolism should be carefully observed during interferon treatment in dialysis patients.
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Lin XN, Zhou ZX, Durairaj V, Schlottmann P, Cao G. Colossal magnetoresistance by avoiding a ferromagnetic state in the Mott system Ca3Ru2O7. PHYSICAL REVIEW LETTERS 2005; 95:017203. [PMID: 16090650 DOI: 10.1103/physrevlett.95.017203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2005] [Indexed: 05/03/2023]
Abstract
Transport and magnetic studies of Ca3Ru2O7 for temperatures ranging from 0.4 to 56 K and magnetic fields B up to 45 T lead to strikingly different behavior when the field is applied along the different crystal axes. A ferromagnetic (FM) state with full spin polarization is achieved for the B//a axis, but colossal magnetoresistance is realized only for the B//b axis. For the B//c axis, Shubnikov-de Haas oscillations are observed and followed by a less resistive state than that for B//a. Hence, in contrast with standard colossal magnetoresistive materials, the FM phase is the least favorable for electron hopping. These properties together with highly unusual spin-charge-lattice coupling near the Mott transition (48 K) are driven by the orbital degrees of freedom.
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Sofic E, Rimpapa Z, Kundurovic Z, Sapcanin A, Tahirovic I, Rustembegovic A, Cao G. Antioxidant capacity of the neurohormone melatonin. J Neural Transm (Vienna) 2005; 112:349-58. [PMID: 15666035 DOI: 10.1007/s00702-004-0270-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2004] [Accepted: 12/12/2004] [Indexed: 10/25/2022]
Abstract
The aim of this study was to elucidate the antioxidant behaviour of melatonin (M) and determine its activity-structure relationship. M or 5-metoxy-N acetyltriptamine is a neurohormone secreted by the pineal gland, which plays a proven role in maintaining sleep-wake rhythms. The antioxidant capacity of M was analysed using the oxygen radical absorbance capacity (ORAC) assay. Furthermore, spectral measurements for aerobic photolytic reaction of neutral red (NR) and degree of inhibition of photolysis with M, glutathione (GSH), ascorbic acid (AA) and vitamin E analogue Trolox were studied at room temperature 25 degrees C, using visible (VIS) and ultra-violet (UV) radiations. In the ORAC assay 2,2-azobis (2-amidino-propane)dihydrochloride (AAPH) a peroxyl radical generator, ROO degrees ; H2O2-Cu2+, mainly a hydroxyl radical generator, degrees OH; and Cu2+ a transition metal were used. Although some studies indicated that M is a powerful antioxidant, no one has compared its antioxidant capacities with GSH, E-vitamin and AA, using three free radical (FR) generators in an assay which utilizes an area-under curve technique and thus combines both inhibition time and inhibition degree of FR action by an antioxidant into a single quantity. In the current study, we used ORAC assay with three FR generators. The assay is based on propensity of the fluorescence emitted by the protein beta-phycoerythrin (beta-PE) from porphyridium cruentum to be quenched when exposed to FR action. M in our experiments acted as a universal antioxidant against ROO degrees and degrees OH radicals. Also, M served as an antioxidant in the presence of Cu2+. M, which is a lipid-soluble compound, was a twice more powerful antioxidant than vitamin E, and four times than AA or GSH. Furthermore, M inhibited aerobic photolysis of NR photoinduced with VIS and UV rays faster and more effectively, than AA, GSH or vitamin E. AA with NR, under aerobic conditions during irradiation with VIS and UV acted as a pro-oxidant. M may be the premier molecule to protect the cells from oxidative stress.
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Toblli JE, Cao G, DeRosa G, Forcada P. Reduced cardiac expression of plasminogen activator inhibitor 1 and transforming growth factor beta1 in obese Zucker rats by perindopril. Heart 2005; 91:80-6. [PMID: 15604340 PMCID: PMC1768649 DOI: 10.1136/hrt.2003.022707] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
OBJECTIVE To determine whether angiotensin converting enzyme inhibition by perindopril can reduce cardiac transforming growth factor beta1 (TGFbeta1) and plasminogen activator inhibitor 1 (PAI-1) and therefore control collagen accumulation in an animal model with the metabolic syndrome such as the obese Zucker rat (OZR). ANIMALS Male OZR (group 1, n = 10); OZR treated with perindopril (group 2, n = 10); and lean Zucker rats (group 3, n = 10). METHODS During six months, group 2 received 3 mg/kg/day of perindopril orally and group 1 and group 3 were given a vehicle. Hearts were processed for pathology studies including immunohistochemical analysis with antibodies to PAI-1, TGFbeta1, collagen type I, and collagen type III. RESULTS Group 2 had lower blood pressure (126.7 (2) v 148.6 (2.7) mm Hg, p < 0.01) than untreated OZR and had decreased cardiac PAI-1 (3.6 (0.4) v 13.5 (1.7)% of positive area/field, p < 0.01), TGFbeta1 in myocytes (0.13 (0.1) v 9.14 (4.7)%/area, p < 0.01) and in interstitium (19.8 (6.8) v 178.9 (27.4) positive cells/area, p < 0.01), collagen I (3 (0.8) v 13.3 (1)%/area, p < 0.01), collagen III (5 (0.6) v 9.5 (0.9)%/area, p < 0.01), and collagen I to collagen III ratio (0.59 (0.13) v 1.40 (0.15) p < 0.01) compared with untreated OZR. CONCLUSION These results suggest that perindopril reduces cardiac PAI-1 and TGFbeta1 and ameliorates cardiac fibrosis in a rat model with multiple cardiovascular risk factors.
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Karpus JF, Gupta R, Barath H, Cooper SL, Cao G. Field-induced orbital and magnetic phases in Ca3Ru2O7. PHYSICAL REVIEW LETTERS 2004; 93:167205. [PMID: 15525028 DOI: 10.1103/physrevlett.93.167205] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2004] [Indexed: 05/24/2023]
Abstract
Magnetic-field- and temperature-dependent Raman scattering studies of Ca3Ru2O7 reveal dramatic field-dependent properties arising from transitions between various complex orbital and magnetic phases, including a field-induced orbital-ordered to orbital-disordered transition (H(o) // hard axis), and a reentrant orbital-ordered to orbital-disordered to orbital-ordered transition (H(o) // easy axis). We find that the dramatic magnetic-field properties are most prevalent in a "mixed"-magnetic and -orbital phase regime, providing evidence for a strong connection between orbital phase inhomogeneity and "colossal" field effects in the ruthenates.
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Pisu M, Cincotti A, Cao G, Pepe F. Prediction of Uncatalysed Calcium Bisulphite Oxidation Under Operating Conditions Relevant to Wet Flue Gas Desulphurization Plants. Chem Eng Res Des 2004. [DOI: 10.1205/0263876041596652] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Toblli J, DeRosa G, Cao G, Piorno P, Pagano P. RENAL PROTECTION OF DUAL BLOCKADE OF RENIN ANGIOTENSIN SYSTEM IN OBESE ZUCKER RAT. J Hypertens 2004. [DOI: 10.1097/00004872-200402001-00468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Qiu Y, Garren J, Samara E, Cao G, Abraham C, Cheskin HS, Engh KR. Once‐a‐Day Controlled‐Release Dosage Form of Divalproex Sodium II: Development of a Predictive In Vitro Drug Release Method. J Pharm Sci 2003; 92:2317-25. [PMID: 14603516 DOI: 10.1002/jps.10486] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
During formulation design of a once-daily controlled release matrix system of divalproex sodium, the in vitro dissolution test (USP II, 100 rpm, pH 6.8 buffer) was found to result in release rates that were slower than in vivo absorption. The test method also did not sufficiently discriminate formulations with different in vivo absorption rates. To develop an in vitro method that is directly correlated with in vivo absorption, statistically designed studies were carried out to investigate the effects of various in vitro testing variables on drug release using USP dissolution apparatuses. The variables studied included agitation intensity, apparatus, pH, surfactant and ionic strength of the dissolution medium. Experimental data were analyzed using ANOVA. In vitro/in vivo correlation was tested based on the hypothesis that the same linear regression equation holds for three formulations with different release rates. A mixed effects model was used in which the dependence among observations from the same subject was taken into account. Factorial studies indicated that higher pH, addition of sodium lauryl sulphate (SLS) to the dissolution medium, and higher agitation intensity increased the release rate from the matrix tablet. Use of SLS not only lead to increased release rates that are more comparable to in vivo absorption rates, but also improved differentiation among formulations with varying release rates. Furthermore, drug release was also affected by interactions among the variables studied. Statistical analysis indicated that a combination of higher SLS concentration and lower pH provided enhanced differentiation between release profiles of the fast and slow releasing formulations. Based on the above findings, a new set of testing conditions was identified and demonstrated to be predictive of in vivo drug absorption for various controlled release formulations of divalproex sodium. The new method uses USP Apparatus II operating at 100 rpm in 500 mL of 0.1 N HCl for 45 min followed by 900 mL of 0.05 M phosphate buffer containing 75 mM SLS, pH 5.5, 37 +/- 0.5 degrees C. In conclusion, adjusting dissolution testing conditions to match the behavior of the formulations in vitro with that in vivo is a useful approach in identifying a predictive method in development of in vitro-in vivo correlation.
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Bechara AJ, Cao G, Casabé AR, Romano SV, Toblli JE. Morphological modifications in clitoris and vagina in spontaneously hypertensive rats. Int J Impot Res 2003; 15:166-72. [PMID: 12904802 DOI: 10.1038/sj.ijir.3900982] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
We evaluated possible morphological alteration in clitoris and vagina from spontaneous hypertensive rats (SHR) and normotensive WKY rats. Clitoris and vagina were processed by Masson's trichrome, anti-alpha-smooth-muscle actin, anticollagen type I (COL I) and type III (COL III), and anti-TGFbeta(1). SHR presented higher amount of clitoral cavernous smooth muscle (CSM), vascular smooth muscle; TGFbeta(1) in clitoral vessel wall; higher wall/lumen ratio in both vaginal and clitoral vessels; and remarkable interstitial fibrosis, expressed by a higher amount in interstitial COL I and III in both clitoris and vagina, compared to WKY rats. Nerve fibers from clitoral and vaginal tissue in SHR showed important fibrosis at perineurium. SHR showed positive correlation between systolic blood pressure (SBP) and clitoral CSM; SBP and fibrosis in clitoris; and SBP and COL I and III in clitoris, respectively. Similar findings were observed between SBP and COL I and III in vagina. In conclusion, SHR present morphologic changes in clitoral vessels as well as in clitoral cavernous space, which have a high positive correlation with the high blood pressure level. Moreover, the increase in extracellular matrix affects not only the clitoral and vaginal interstitium but also the nerve structures from both clitoris and vagina.
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Jiang M, Ma Y, Ni X, Cao G, Ji C, Cheng H, Tang R, Xie Y, Mao Y. Molecular cloning and characterization of a novel human gene (ANP32E alias LANPL) from human fetal brain. Cytogenet Genome Res 2003; 97:68-71. [PMID: 12438741 DOI: 10.1159/000064058] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Leucine-rich acidic nuclear protein (LANP) is a member of the leucine-rich repeats (LRRs) superfamily. Here we report on a human homologue of LANP, encoded by the gene ANP32E (alias LANPL). The gene was cloned and identified during large-scale sequencing analysis of a human fetal brain cDNA library. The human protein shared 70% amino acid identity with rat LANP. According to bioinformatics analysis, ANP32E is located on chromosome 1q22. RT-PCR analysis indicates that ANP32E was expressed in human peripheral blood leukocytes, colon, small intestine, prostate, thymus, spleen, skeletal muscle, liver and kidney.
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