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41.
Background: Gamma‐hydroxybutyrate (GHB) may be an interesting hypnotic agent in burn patients because of its good respiratory or hemodynamic tolerance. However, its clinical and electroencephalographic (EEG) sedative effects are not yet described in children. The aim of this prospective and randomized study was to assess clinical and EEG effects of increasing intravenous (IV) doses of GHB in burn children requiring sedation for burn wound cares. Methods: Thirty six children hospitalized in a burn care unit were included and randomly assigned into three groups (G) according to the single IV dose of GHB they received before burn wound care: 10 mg·kg?1 in G10, 25 mg·kg?1 in G25, or 50 mg·kg?1 in G50. All patients received oral premedication (morphine and hydroxyzine) 30 min before GHB injection. Respiratory rate, heart rate, pulse oximetry, and bispectral index (BIS) were continuously monitored. Depth of sedation was clinically assessed using Observer’s Assessment of Alertness and Sedation (OAAS) Score, every 2 min until recovery (i.e., OAAS = 4). Results: Median age was 17.5 [12–34] months. Whatever the dose, BIS decreased after IV GHB. Nadir value of BIS was significantly lower in G25 and G50 than in G10, as was for OAAS score. Nadir values were reached after same delays in G25 and G50. Duration of sedation was dose‐dependant. Conclusion: Bispectral index decreased after GHB injection and was correlated with OAAS score. Deep sedation can be safely achieved with IV doses of 25 or 50 mg·kg?1, but the last dose was associated with prolonged duration of clinical sedation.  相似文献   
42.
Antiviral therapy with interferon-alpha (IFN-alpha) and pegylated IFN-alpha (PEG-IFN-alpha) for chronic hepatitis C (HCV)-infected kidney recipients remains controversial. IFN-alpha is not recommended in most cases because it induces severe acute graft rejection. However, IFN-alpha, as PEG-IFN-alpha, is associated with a more pronounced immune response, and is well tolerated in HCV-infected liver recipients without causing graft rejection. In combined liver-kidney transplant (LKT) recipients, IFN-alpha has been occasionally used and appears to be well tolerated. All LKT recipients with a functioning kidney and liver having a HCV replication and who needed IFN-alpha therapy have been included in the study. The occurrence of liver and/or renal acute rejection as well as the HCV replication has been collected. A total of 12 LKT patients treated with PEG-IFN-alpha plus ribavirin have been studied. No acute rejection was observed. Renal function remained stable during and after discontinuing treatment, without any graft dysfunction. Two patients had a partial viral response and four had a sustained viral response. All patients, whatever their viral response, had decreased liver-enzyme levels. Response to PEG-IFN-alpha therapy was correlated with steroid dose and transaminase level when PEG-IFN-alpha was started. These data suggest that the combination therapy of PEG-IFN-alpha plus ribavirin did not have a higher risk of acute kidney-graft rejection after liver-kidney transplantation.  相似文献   
43.

Introduction

It is known that chronic kidney disease (CKD) and senescence bring about a progressive reduction in glomerular filtration rate (GFR) and that in the former this is usually associated with an increase in the fractional excretion of calcium, phosphorus, magnesium, and uric acid. However, it has not yet been explained how these substances are excreted in the healthy oldest old. Thus, in the present study, we examined the renal handling of these substances in very aged people in comparison with CKD patients with similar GFR levels (stage III??CKD).

Materials and methods

Twenty volunteers were studied; 10 of them were healthy very old (VO) (??75?years old) individuals and 10 were stage III CKD patients. Exclusion criteria were as follows: presence of altered (abnormally high or low) plasma calcium, phosphorus, magnesium and uric acid, as well as previous diagnoses of diabetes mellitus and obstructive uropathy and use of drugs that could alter plasma levels of the studied substances. All volunteers were on a diet with the same content of these elements (3-day dietary register). We measured calcium, phosphorus, magnesium, uric acid, creatinine in serum plasma and morning urine, as well as serum parathyroid hormone level, in each volunteer. From these data, fractional excretion (FE) of these substances was obtained. A statistical analysis was carried out using the Wilcoxon test.

Results

Serum creatinine: 1.8?±?0.4?mg/dl (CKD) versus 0.8?±?0.2?mg/dl (VO), p?=?0.0002; serum calcium: 9.1?±?0.3?mg/dl (CKD) versus 8.7?±?0.4 (VO), p?=?0.022; serum magnesium: 2.3?±?0.2?mg/dl (CKD) versus 2.0?±?0.1 (VO), p?=?0.05; serum phosphorus: 3.9?±?0.5?mg/dl (CKD) versus 3.0?±?0.4?mg/dl (VO), p?=?0.002; serum uric acid: 6.6?±?1.5 (CKD) versus 5.2?±?1.4?mg/dl (VO), p?=?0.04; FE of calcium: 2.5?±?1?% (CKD) versus 0.8?±?0.3?% (VO), p?=?0.04; FE of magnesium: 7.2?±?4.1?% (CKD) versus 2.9?±?0.9?% (VO), p?=?0.02; FE of phosphorus: 25?±?9?% (CKD) versus 9.1?±?5.7(VO), p?=?0.001; FE of uric acid: 10?±?3?% (CKD) versus 8?±?5?% (VO), p?=?0.05.

Conclusion

Serum levels and FE of calcium, phosphorus, magnesium and uric acid were significantly higher in CKD patients compared to healthy very old people with similar GFR, except for serum magnesium and FE of uric acid, which were similar in both groups.  相似文献   
44.
PURPOSE: During liver transplantation, excessive blood losses are correlated with increased morbidity and mortality. Blood losses are particularly high in the case of urgent liver transplantation for fulminant hepatic failure (FHF). Recombinant activated factor VII (rFVIIa) has shown promise in treating the coagulopathy of liver disease. We review our experience with the use of rFVIIa in treating the coagulopathy of FHF during urgent liver transplantation. CLINICAL FEATURES: We report four patients with FHF who met King's College criteria for liver transplantation and in whom rFVIIa was used after conventional means for treating the associated coagulopathy had failed. In all patients, the coagulation defect was corrected by rFVIIa. However, thrombotic complications occurred in two patients (myocardial ischemia and portal vein thrombosis) and the implication of rFVIIa cannot be excluded. CONCLUSION: We conclude that rFVIIa is effective in the correction of the coagulopathy associated with FHF. However, thrombotic events are of concern and therefore, further studies are warranted to define the safety of rFVIIa in that setting.  相似文献   
45.
Vector-borne infections of humans with the protozoan parasite Leishmania (L.) infantum can cause a systemic and potentially lethal disease termed visceral leishmaniasis. In the corresponding mouse model, an intravenous infection with L. infantum leads to the persistence of parasites in various organs, including bone marrow (BM). Considering the anatomical proximity between the BM and the cortical bone, we investigated whether a chronic infection with L. infantum affected bone homeostasis. Unexpectedly, chronic infection with L. infantum caused an increase in bone mass in mice. In vivo, an increased number of osteoblasts and osteocytes and a decreased maturation of osteoclasts characterized the phenotype. Confocal laser scanning fluorescence microscopy confirmed the infection of BM macrophages but also revealed the presence of parasites in osteoclasts. In vitro, mature osteoclasts took up L. infantum parasites. However, infection of osteoclast progenitors abolished their differentiation and function. In addition, secretory products of infected BM–derived macrophages inhibited the maturation of osteoclasts. Both in vitro and in vivo, infected macrophages and osteoclasts showed an enhanced expression of the anti-osteoclastogenic chemokine CCL5 (RANTES). Neutralization of CCL5 prevented the inhibition of osteoclast generation seen in the presence of culture supernatants from L. infantum-infected macrophages. Altogether, our study shows that chronic infection with Leishmania increases bone mass by inducing bone formation and impairing osteoclast differentiation and function. © 2022 American Society for Bone and Mineral Research (ASBMR).  相似文献   
46.
Ischemic acute renal failure is characterized by damages to the proximal straight tubule in the outer medulla. Lesions include loss of polarity, shedding into the tubule lumen, and eventually necrotic or apoptotic death of epithelial cells. It was recently shown that peroxisome proliferator-activated receptor beta/delta (PPARbeta/delta) increases keratinocyte survival after an inflammatory reaction. Therefore, whether PPARbeta/delta could contribute also to the control of tubular epithelium death after renal ischemia/reperfusion was tested. It was found that PPARbeta/delta+/- and PPARbeta/delta-/- mutant mice exhibited much greater kidney dysfunction and injury than wild-type counterparts after a 30-min renal ischemia followed by a 36-h reperfusion. Conversely, wild-type mice that were given the specific PPARbeta/delta ligand L-165041 before renal ischemia were completely protected against renal dysfunction, as indicated by the lack of rise in serum creatinine and fractional excretion of Na+. This protective effect was accompanied by a significant reduction in medullary necrosis, apoptosis, and inflammation. On the basis of in vitro studies, PPARbeta/delta ligands seem to exert their role by activating the antiapoptotic Akt signaling pathway and, unexpectedly, by increasing the spreading of tubular epithelial cells, thus limiting potentially their shedding and anoikis. These results point to PPARbeta/delta as a remarkable new target for preconditioning strategies.  相似文献   
47.
Relevance of Toll-like receptor-4 polymorphisms in renal transplantation   总被引:10,自引:0,他引:10  
BACKGROUND: Polymorphisms in Toll-like receptor-4 (TLR4) have been reported to be associated with a blunted immune response to microbial pathogens, as well as a decreased risk of atherosclerosis in the general population. We assessed the impact of the two TLR4 variants on the risk of severe infection, the incidence of acute rejection, and the occurrence of atherosclerotic complications in renal transplant recipients (RTR). METHODS: TLR-4 polymorphisms were assessed in a cohort of 238 RTR. Post-transplant atherosclerotic events, acute rejection, severe bacterial infection, cytomegalovirus (CMV) disease, and opportunistic infections were evaluated as outcomes. RESULTS: The patients were followed for a mean duration of 95 +/- 29 months after transplant. TLR4 polymorphism was observed in 27 (11.3%) RTR. Subjects with TLR4 polymorphisms were less likely to experience post-transplant atherosclerotic events (RR 0.44; 95% CI 0.21 to 0.93; P= 0.02) and acute rejection (RR 0.41; 95% CI 0.30 to 0.83; P= 0.01), but presented severe bacterial infections (RR 1.33; 95% CI 1.12 to 1.67; P= 0.01) and opportunistic infections (RR 3.03; 95% CI 1.72 to 8.29; P= 0.008) more frequently. TLR4 polymorphism was marginally associated with CMV disease (RR 1.47; 95% CI 0.95 to 2.64; P= 0.08). CONCLUSION: RTR with TLR4 polymorphism present a lower risk of post-transplant atherosclerotic events and acute allograft rejection, but experience severe infectious episodes more frequently. This subset of RTR may benefit from a less potent immunosuppression regimen, along with increased preventive measures against infectious agents.  相似文献   
48.
D Didier  O Ratib  R Lerch  B Friedli 《Radiographics》2000,20(5):1279-99; discussion 1299-301
Magnetic resonance (MR) imaging is rapidly gaining acceptance as an accurate, reproducible, noninvasive method for optimal assessment of structural and functional parameters in patients with valvular heart disease. The severity of valvular regurgitation can be evaluated with cine gradient-echo MR imaging, which allows measurement of the area of the signal void corresponding to the abnormal flow jet. Alternatively, this modality can be used to obtain ventricular volumetric measurements and calculate the regurgitant fraction, or velocity-encoded cine (VEC) MR imaging can be used to quantify regurgitant blood flow. The severity of valvular stenosis can be determined by evaluating the flow jet and associated findings with either modality or by using VEC MR imaging to calculate the transvalvular pressure gradient and valve area. Dynamic MR imaging allows accurate assessment of ventricular function and comprehensive evaluation of pathophysiologic changes. In addition, good interstudy reproducibility suggests a role for VEC MR imaging in assessing the effects of therapeutic intervention and monitoring regurgitant fraction, thereby helping in surgical planning and the prevention of ventricular dysfunction. With greater cost-effectiveness and the increasing availability of new hardware and more advanced techniques, MR imaging will become a routine procedure in valvular heart disease.  相似文献   
49.
The course of autosomal dominant polycystic kidney disease (ADPKD) varies among individuals, with some reaching ESRD before 40 years of age and others never requiring RRT. In this study, we developed a prognostic model to predict renal outcomes in patients with ADPKD on the basis of genetic and clinical data. We conducted a cross-sectional study of 1341 patients from the Genkyst cohort and evaluated the influence of clinical and genetic factors on renal survival. Multivariate survival analysis identified four variables that were significantly associated with age at ESRD onset, and a scoring system from 0 to 9 was developed as follows: being male: 1 point; hypertension before 35 years of age: 2 points; first urologic event before 35 years of age: 2 points; PKD2 mutation: 0 points; nontruncating PKD1 mutation: 2 points; and truncating PKD1 mutation: 4 points. Three risk categories were subsequently defined as low risk (0–3 points), intermediate risk (4–6 points), and high risk (7–9 points) of progression to ESRD, with corresponding median ages for ESRD onset of 70.6, 56.9, and 49 years, respectively. Whereas a score ≤3 eliminates evolution to ESRD before 60 years of age with a negative predictive value of 81.4%, a score >6 forecasts ESRD onset before 60 years of age with a positive predictive value of 90.9%. This new prognostic score accurately predicts renal outcomes in patients with ADPKD and may enable the personalization of therapeutic management of ADPKD.  相似文献   
50.
Cryptogenic cirrhosis (CC) is diagnosed in 5-30% of cirrhotic patients overall and 7% of patients who undergo liver transplantation for cirrhosis. In our series of patients transplanted for CC, pre-transplant clinical and histological data and the post-transplant course were reexamined in an attempt to identify the aetiology. Among the 881 patients transplanted in our centre between 1987 and 2000, 28 patients with a median age of 46 yr (range: 18-69) at transplantation were initially classified as having CC. Two patients were excluded because of intense ischaemic lesions caused by chemoembolization prevented histological analysis of the native liver (n = 1) and because of cryptic HBV infection (n = 1). Among the remaining 26 patients, four groups were individualized: (i) patients with chronic inflammatory liver disease with autoimmune features (n = 14, 54%); (ii) patients with features suggestive of non-alcoholic fatty liver disease (n = 3, 11.5%); (iii); patients with incomplete septal cirrhosis (ISC) and vascular liver disease (n = 3), and (iv) patients with unresolved CC (n = 6, 23%). In the autoimmune liver disease group, the median International Autoimmune Hepatitis score was 12.5 (range: 11-19) after reevaluation and review of the post-transplantation course was helpful to confirm the diagnosis with the occurrence of active graft hepatitis in nine patients, with autoantibodies in five patients. The vascular group was characterized by lesions of obliterative portal venopathy and ISC in all native livers. Diagnosis of NAFLD was based on the clinical background of obesity and/or type 2 diabetes and the presence of steatosis or steatohepatitis in native livers and graft biopsies. A definite aetiological diagnosis can be achieved in the majority of patients initially diagnosed with CC. Autoimmune liver disease emerged as the main aetiology (14 of 26 patients, 54%) and frequently recurred on the grafted liver (nine cases). In all cases a precise diagnosis is obviously of practical interest for better management of post-transplant survey and treatment.  相似文献   
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