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81.
82.
BACKGROUND: Mycophenolate mofetil (MMF) in conjunction with calcineura antagonists has been shown to prevent acute rejection in renal allograft recipients. Its role in treatment of chronic rejection or allograft nephropathy is still controversial. We initiated the study to investigate the effect of adding MMF to a cyclosporine plus prednisolone regimen in renal recipients with chronic allograft nephropathy. MATERIALS AND METHODS: We retrospectively studied 36 patients with chronic allograft nephropathy, defined clinically as increased of serum creatinine, proteinuria, and hypertension. Renal function, cyclosporine level, renal biopsy, and renal scan were regularly done as indicated. MMF was added to 20 recipients after initial treatment with cyclosporine and prednisolone. The other 16 recipients were managed without adding MMF. Serum creatinine was monitored for 3 years. RESULTS: The demographic characteristics of the patients in the two groups were comparable. The average dose of prednisolone was unchanged throughout the study and the trough level of cyclosporine was maintained in the range of 100 to 150 ng/mL. The serum creatinine decreased initially in the group on MMF, but renal function deteriorated progressively after 6 months. There was a difference in serum creatinine between the two groups but this did not reach statistical significance. CONCLUSION: MMF therapy tender to improve renal function initially but did not attenuate significantly the impairment in chronic allograft nephropathy.  相似文献   
83.
Cutaneous burn wounds represent a significant public health problem with 500,000 patients per year in the USA seeking medical attention. Immediately after skin burn injury, the volume of the wound burn expands due to a cascade of chemical reactions, including lipid peroxidation chain reactions. Such expansion threatens life and is therefore highly clinically significant. Based on these chemical reactions, the present paper develops for the first time a three-dimensional mathematical model to quantify the propagation of tissue damage within 12 hours post initial burn. We use the model to investigate the effect of supplemental antioxidant vitamin E for intercepting propagation. We show, for example, that if tissue levels of vitamin E tocotrienol are increased, postburn, by five times then this would slow down the lipid peroxide propagation by at least 50%. We chose the alpha-tocotrienol form of vitamin E as it is a potent inhibitor of 12-lipoxygenase, which is known to propagate oxidative lipid damage. Our model is formulated in terms of differential equations, and sensitivity analysis is performed on the parameters to ensure the robustness of the results.  相似文献   
84.
Hsu HT  Chou SH  Wu PJ  Tseng KY  Kuo YW  Chou CY  Cheng KI 《Anaesthesia》2012,67(4):411-415
Intubation with a double‐lumen tube is important for achieving one‐lung ventilation and facilitating thoracic surgery. The GlideScope® videolaryngoscope (Verathon Inc., Bothell, WA, USA) is designed to assist tracheal intubation for patients with a difficult airway. We wished to compare the GlideScope and direct laryngoscopy for double‐lumen tube intubation. Sixty adult patients requiring a double‐lumen tube for thoracic surgery and predicted uncomplicated laryngoscopy were randomly assigned to a direct Macintosh laryngoscopy group (n = 30) or a GlideScope group (n = 30). The mean (SD) duration of intubation was longer in the Macintosh group (62.5 (29.7) s) than in the GlideScope group (45.6 (10.7) s; p = 0.007). There was no difference in the success of the first attempt at intubation (26/30 (87%) and 30/30 (100%) for Macintosh and GlideScope groups, respectively; p = 0.112). The incidence of sore throat and hoarseness was higher in the Macintosh group (18 (60%) and 14 (47%), respectively) than in the GlideScope group (6 (20%) and 4 (13%), respectively; p = 0.003 and 0.004). We conclude that double‐lumen tube intubation in patients with predicted normal laryngoscopy is easier using the GlideScope videolaryngoscope than the Macintosh laryngoscope.  相似文献   
85.

Background

Predonation kidney function may be an important factor affecting graft outcome. Increased baseline allograft function may be more effective than strategies to slow the decline in glomerular filtration rate (GFR). However, the role of donor effective renal plasma flow (ERPF) on long-term outcome is less well understood. The purpose of this study was to examine the relationship between preoperative allograft function as measured by ERPF and the decline of allograft function as defined by the annualized change in GFR among living-donor kidney transplant recipients.

Methods

We performed a retrospective analysis of 83 patients who underwent living donor renal transplantation at our institution from March 2001 to October 2010. A time series analysis of autoregressive integrated moving average (ARIMA) model was applied to determine the annualized change in GFR after transplantation. Univariate and stepwise multivariate analyses were performed using linear regression between preoperative ERPF and annualized change in GFR after transplantation. We also investigated the influence on annualized change in GFR of other donor or recipient variables.

Results

The ARIMA model revealed that the annualized change in GFR was −1.344 ± 12.476 mL/min/1.73 m2 per year. Pearson correlation coefficient for the association between predonation ERPF of the transplanted kidney and the annualized change in GFR was 0.033 (P = .777).

Conclusions

Poor predonation kidney function was not associated with an increased rate of decline of allograft function. Neither donor age nor renal function (preoperative ERPF value) was a valid predictor of change in GFR among living-donor kidney transplant recipients.  相似文献   
86.

Purpose

The aim of this study was to evaluate risk factors for an acute cellular rejection episode (ARE) among adult liver transplant (OLT) patients.

Materials and methods

We retrospectively reviewed 110 consecutive patients who underwent OLT between May 2007 and December 2010. The diagnosis of ARE was based upon clinical and biochemical data; liver biopsy was only performed when clinical presentation was equivocal. We recorded donor and recipient characteristics, perioperative immune status, and postoperative laboratory data. Forty patients (36.4%) who suffered a clinical rejection episode and received pulsed or recycled steroid therapy (R group), were compared with 70 (63.6%) free of rejection (N group).

Results

The mean age of R recipients was 46.61 ± 9.97 years, which was younger than the N group (51.86 ± 8.37, P = .005). R group patients displayed a lower pre-OLT creatinine (P = .016) and higher alanine aminotransferase (P = .048). Cox regression model showed recipient age to be the only significant factor to predict ARE (odds ratio = 1.071, P = .003). The cutpoint of age was 46 years by receiver operating characteristic analysis. Patients younger than 46 years showed higher initial CD8+ T-cell counts (P = .038).

Conclusion

Recipient age was significantly associated with ARE; younger patients showed higher CD8+ lymphocyte counts than older patients. More aggressive immunosuppression should be considered for younger recipients to prevent ARE.  相似文献   
87.
Effect of pretreatment with ketorolac on propofol injection pain   总被引:2,自引:0,他引:2  
BACKGROUND: : Pain on injection is still a major problem with propofol. We performed this study to compare different doses of intravenous (i.v.) ketorolac with and without venous occlusion and its effect on the incidence and the severity of the pain after propofol injection. METHODS: We conducted a prospective, randomized and double-blind study of 180 patients (20-60 years of age.) scheduled to undergo elective surgery. Six groups of patients were generated: group A received normal saline (NS) 2 ml i.v.; groups B, C, D received ketorolac 10 mg in 2 ml NS with venous occlusion (VO) and a subsequent propofol injection at either 30, 60 or 120 s; groups E and F received ketorolac 15 mg and 30 mg in 2 ml NS and propofol was injected after 60 s. The pain perception was assessed during injection of propofol in all patients. RESULT: : The incidence of propofol-associated injection pain was for A: 46.7%; B: 43.4%; C: 23.3%; D:16.7%; E: 20%, and F: 10%. The incidence of pain following propofol injection was reduced by i.v. ketorolac 10 mg with venous occlusion for 120 s. Furthermore, i.v. ketorolac 15 mg and 30 mg but not 10 mg following propofol injection after 60 s without venous occlusion revealed significant pain reduction when compared to saline group. There was no difference in venous sequelae at 7 days postoperatively between the groups. CONCLUSION: Our results suggested that pretreatment with i.v. 15 and 30 mg ketorolac reduces pain following propofol injection. Moreover, pretreatment with i.v. ketorolac 10 mg with venous occlusion for 120 s achieves the same pain relief effect.  相似文献   
88.
The change in sexual hormones with age in middle-aged and elderly Chinese men, with and without erectile dysfunction (ED), was investigated. Total testosterone (TT), free testosterone (FT), dehydroepiandrosterone sulfate (DHEAS), and sex hormone-binding globulin (SHBG) were determined from fasting serum samples by radioimmunoassay in 627 middle-aged and elderly ethnic Chinese men with and without ED. Calculated FT was derived from TT and SHBG. Patients with ED were subdivided into groups having low serum TT (<2.7 ng/ml) and normal TT (> or =2.7 ng/ml). FT and DHEAS declined and SHBG rose with age in both normal patients and in patients with ED. TT and SHBG were lower in patients with ED than in normal subjects at all ages. In contrast to findings in previous studies, levels of FT were higher in patients with ED than in normal subjects. Hormonal changes in this Chinese population generally mirrored those in previously studied ethnic populations, except for higher FT in patients with ED. This suggests that hormonal levels in patients with ED may vary in different populations. The significance and reproducibility of this finding remains to be determined.  相似文献   
89.

Background Context

Disc degeneration is associated with the progressive loss of the proteoglycan content of the intervertebral disc, decreased matrix synthesis, higher concentrations of proteolytic enzymes, and increased levels of proinflammatory cytokines. In previous studies, we have shown that C-C chemokine ligand (CCL)2, CCL3, and CCL5 are highly expressed by cultured nucleus pulposus (NP) and annulus fibrosus (AF) cells that have been treated by interleukin-1. The major function of these chemokines is to recruit immune cells into the disc. It is unclear if disc cells can respond to these chemokines. Recent studies by Phillips et al. (2015) showed that NP cells express a number of cytokines and chemokine receptors.

Purpose

The purpose of this study is to determine the gene and protein expression of C-C chemokine receptor (CCR)1, CCR2, and CCR5 in NP and AF cells, and to test if these receptors can respond to their ligands in these cells by cell signaling and migration.

Study Design/Setting

This is an in vitro study.

Methods

For RNA, surface expression, and cell signaling studies, human cells were isolated from the NP and AF tissues collected after spine surgery or from donated spine segments (Gift of Hope Human Donor & Tissue Network of Illinois) and cultured in monolayer. The gene expression of human CCR1, CCR2, and CCR5 was analyzed using real-time polymerase chain reaction. The surface expression of CCR1, CCR2, and CCR5 was analyzed using flow cytometry and fluorescently tagged antibodies specific for these proteins. Extracellular signal-regulated kinase (ERK) phosphorylation was analyzed from the cell lysates of NP and AF cells treated with CCL2 and CCL5 for 1 hour using enzyme-linked immunosorbent assay. Migration of primary rabbit AF cells was assayed using 8-µm Corning Transwell inserts in the presence or absence of CCL5. This study was partially funded by a North American Spine Society 2014 Basic Research Grant Award ($50,000).

Results

RNA analysis showed that gene expression of CCR1, CCR2, and CCR5 was evident in human NP and AF cells (n=6). Only a small population of NP and AF cells expressed CCR1 (1.9% and 1.2%, respectively) and CCR2 (0.8% and 1.4%, respectively) on the cell surface, whereas a larger percentage expressed CCR5 (12.7% and 11.6%, respectively). Significantly higher levels of ERK phosphorylation were detected in AF cells after treatment with CCL5 and not CCL2. Treatment with either chemokine did not cause significantly higher ERK phosphorylation in NP cells. There was an increase in average AF cell migration in the presence of CCL5. The increase was significant when the migration was induced with CCL5 (500?ng/mL) at both 2- and 6-hour time points.

Conclusions

CCR5 is expressed at the RNA level and on the cell surface of NP and AF cells. In the presence of CCL5, we detected increased levels of ERK phosphorylation and AF cell migration, suggesting that the CCR5 receptors in AF cells are functional. These data suggest that AF cells may have the ability to migrate in response to disc damage or inflammation.  相似文献   
90.

Background

Acoustic radiation force impulse (ARFI) imaging is a noninvasive imaging modality for quantitative assessment of tissue stiffness. This study utilized ARFI imaging to assess the stiffness of a transplant renal cortex within the first month after renal transplantation and to explore the correlation between the cortical stiffness and arterial resistance of the transplant kidney.

Methods

Forty renal transplant recipients (male/female = 26/14; mean age: 45.3 years; deceased donor/living related donor = 27/13) were included in this study. ARFI imaging with virtual touch tissue imaging quantification was applied to assess the stiffness of the transplant renal cortex by using a linear ultrasound transducer. Arterial resistance was acquired by spectral Doppler examination of the main artery and intrarenal arteries of the transplant kidney using a curvilinear ultrasound transducer.

Results

The stiffness of transplant renal cortex was expressed as shear wave velocity (m/s). The mean value of cortical stiffness was 3.19 ± 1.01 m/s (range: 1.55–5.54). The stiffness of transplant renal cortex was positively correlated with the resistance index of the main renal artery (r = 0.55, P = .001), segmental artery (r = 0.43, P = .005), and interlobar artery (r = 0.42, P = .006).

Conclusion

The stiffness of a transplant renal cortex is positively correlated with the arterial resistance of the renal transplant in the early post-transplant period. This result indicates that, in addition to renal fibrosis, the stiffness of the transplant renal cortex is also influenced by the hemodynamics of the transplant kidney.  相似文献   
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