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41.
Complement activation plays a key role in mediating apoptosis, inflammation, and transplant rejection. In this study, the role of the complement 5a receptor (C5aR) was examined in human renal allografts and in an allogenic mouse model of renal transplant rejection. In human kidney transplants with acute rejection, C5aR expression was increased in renal tissue and in cells infiltrating the tubulointerstitium. Similar findings were observed in mice. When recipient mice were treated once daily with a C5aR antagonist before transplantation, long-term renal allograft survival was markedly improved compared with vehicle-treatment (75 versus 0%), and apoptosis was reduced. Furthermore, treatment with a C5aR antagonist significantly attenuated monocyte/macrophage infiltration, perhaps a result of reduced levels of monocyte chemoattractant protein 1 and the intercellular adhesion molecule 1. In vitro, C5aR antagonism inhibited intercellular adhesion molecule 1 upregulation in primary mouse aortic endothelial cells and reduced adhesion of peripheral blood mononuclear cells. Furthermore, C5aR blockade markedly reduced alloreactive T cell priming. These results demonstrate that C5aR plays an important role in mediating acute kidney allograft rejection, suggesting that pharmaceutical targeting of C5aR may have potential in transplantation medicine.  相似文献   
42.
The aim of the current study was to examine the correlation between lumbar lordosis, spinal fusion, and functional outcome in patients suffering from severe low back pain, treated by posterolateral spinal fusion with or without pedicle screw instrumentation. One hundred thirty patients were randomly allocated to posterolateral lumbar fusion with or without Cotrel-Dubousset instrumentation. Functional outcome was assessed preoperatively, and 1 and 2 years postoperatively. Lordosis angles of the lumbar spine and fusion rates were assessed at the 1- and 2-year follow-up. No difference in lordosis angle was found between the two groups at any time. Lordosis was unchanged at 2 years compared with preoperative status in both groups. In the instrumented group, nonunion (23%) was followed by a decrease in lordosis at follow-up (p < 0.05). However, in the noninstrumented group, nonunion (14%) resulted in increased lordosis (p < 0.05). No correlation was found between functional outcome and lordosis angle. The current study showed no correlation between functional outcome and lordosis angle either before or after posterolateral spinal fusion. Use of instrumentation did not influence lumbar spinal alignment compared with noninstrumented fusions. The sagittal alignment was stable both 1 and 2 years after solid fusion. The failure mode of instrumented fusions was a reduced degree of lordosis in contrast to an increased degree of lordosis in patients with noninstrumented fusion.  相似文献   
43.
It has been demonstrated that total parenteral nutrition (TPN) modulates the function of the hepatic reticuloendothelial system (RES). The objective of this study was to evaluate the impact of two different TPN lipid emulsions on the recovery of allograft RES function after orthotopic liver transplantation (OLTx). In a prospective, double-blind study, OLTx patients were randomly assigned to two treatment groups. Group I ( n=13) received a TPN regimen that included long-chain triglycerides (LCT). Group II ( n=9) received a TPN regimen that included a fat emulsion consisting of both medium-chain triglycerides (MCT) and LCT. At baseline, i.e., on days 2 or 3 after OLTx ( t1), before lipids for TPN were started, hepatic RES function was determined using the human serum albumin millimicrosphere technique (K-value, 1/min). A second measurement ( t2) was obtained after 7 days of TPN, including one of the study's two fat emulsions. The mean (+/- SD) K-value (1/min) was 0.48+/-0.16 in the LCT group and 0.55+/-0.28 in the MCT/LCT group at t1, and it improved to 0.62+/-0.21 in the LCT group and to 0.86+/-0.32 in the MCT/LCT group at t2. RES function recovery was significantly better in the MCT/LCT group ( P< or = 0.05). MCT/LCT emulsion appears to be the TPN fat emulsion of choice after OLTx as it seems to have less impact on hepatic RES recovery.  相似文献   
44.
BACKGROUND: There is increasing evidence that paediatric kidneys transplanted to adults have good graft function and satisfactory graft survival. The relationship between size increment and functional potential of paediatric kidneys following transplantation is not defined in detail. We therefore initiated a prospective single centre study, comprising detailed and repeated measurements of size and function of paediatric kidneys transplanted to adults. METHODS: Nineteen adults receiving a first kidney transplant from a paediatric donor (<10 years of age) were included in the study. All patients were followed for 12 months post-transplant. Increment in size and function of the transplanted kidneys were assessed by ultrasound, glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). All tests were performed during the first week, post-transplant and subsequently repeated at 1, 3, 6 and 12 months. RESULTS: Kidney volume increased 2.6-fold at 12 months (P < 0.001). GFR and ERPF showed a slightly more moderate increase, 1.8-fold and 1.6-fold, respectively. Patient and graft survival at 1 year were 100% and serum creatinine was 91 micromol/l (66-169). CONCLUSION: The study indicates that paediatric kidneys for transplantation may be considered as excellent rather than being referred to as suboptimal for adult recipients, at least the first year after transplantation.  相似文献   
45.
BACKGROUND: The purpose of the study was to analyze the actual injury situation of bicyclists in Germany to create a basis for effective preventive measures. METHODS: Technical and medical data were prospectively collected shortly after the crash at the crash scenes. RESULTS: Included were 4,264 injured bicyclists from 1985 to 2003. Fifty-five percent of the bicyclists were male and 45% were women. The mean age of bicyclists was 52.0 years. The crashes took place in urban areas in 95.2% of the cases, and in rural areas in 4.8% of the cases. Collision opponents were cars in 65.8%, trucks in 7.2%, bicyclists in 7.4%, standing objects in 8.8%, multiple opponents or objects in 4.3%, and others in 6.5%. The mean collision speed was 21.3 km/h. The helmet use rate was 1.7%. Fifty-five percent of bicyclists used bicycle traffic lanes before the crash. The mean Maximum Abbreviated Injury Scale/Injury Severity Score (ISS) was 1.45 of 3.9. The incidence of multiple injuries (ISS>16)/death was 2.0%/1.5%. The ISS/Maximum Abbreviated Injury Scale score was higher in bicyclists without a helmet than in bicyclists with a helmet, and in bicyclists who had not used bicycle traffic lanes than in bicyclists who had used bicycle traffic lanes (t test, p<0.05). CONCLUSION: In bicyclists, head and extremities are at high risk for injuries. The helmet use rate is unsatisfactorily low. Remarkably, two-thirds of the head injuries could have been prevented by helmets. More consequent helmet use and an extension of bicycle traffic lanes for a better separation of bicyclists and motorized vehicles would be simple but very effective preventive measures.  相似文献   
46.
BACKGROUND: There is a major clinical need for strategies for adequately reconstructing the soft tissue defects found after deep burns, tumor resection, or trauma. A promising solution is adipose tissue engineering with preadipocytes, stem-cell derived precursors of the adipose tissue, implanted within biomaterials. This pilot study evaluated hyaluronan gels mixed with autologous undifferentiated preadipocytes in a pig model for their potency to generate new fat. MATERIALS AND METHODS: Preadipocytes were isolated from intra-abdominal pig fat by collagenase digestion, plated on fibronectin-coated culture dishes in Dulbecco's modified Eagle medium/Ham's F12 (Biochrom, Berlin, Germany) combined with 10% pig serum, expanded, and mixed with hyaluronan gel. Two types of gels with varying degrees of amidation of the carboxyl groups were tested (HYADD3, HYADD4). Cell-loaded gels and unseeded controls were injected subcutaneously into the ears of three pigs, explanted at 6 wk, and analyzed histologically. RESULTS: Both cell-loaded specimens were detected macroscopically. They demonstrated a slight volume effect with limited stability after 6 wk. Unloaded HYADD3 and HYADD4 controls could not be identified at the time of explantation. Histology of HYADD3 revealed islets of mature adipocytes and vessels embedded in fat tissue surrounded by gel. In contrast, no fat formation was found in HYADD4 gels when implanted in the ear. CONCLUSIONS: Histological findings demonstrate that HYADD3 is a promising gel for generating adipose tissue. Even though HYADD3 might be a potential material for the reconstruction of small tissue defects, the question remains as to whether the adipose tissue within the gel is attributable to preadipocyte maturation or ingrowth from neighboring tissue.  相似文献   
47.
48.
Background:  Photodynamic therapy (PDT) is increasingly used for the treatment of actinic keratosis (AK).
Objectives:  To investigate both the efficacy of different application times and the safety of a novel patch (PD P 506 A) containing aminolaevulinic acid in the PDT of mild to moderate AK.
Methods:  Applications of PD P 506 A for 0.5, 1, 2 and 4 h were compared in a multicentre, randomized, blinded-observer, parallel-group study. After patch removal, study lesions were illuminated with red light ( λ em ≈ 630 nm; 37 J/cm2). Study lesions were not pretreated (e.g. by curettage) prior to PDT. Efficacy was evaluated 4 and 8 weeks after treatment. Safety and tolerability were determined through laboratory analyses and documentation of both local reactions and adverse events.
Results:  A total of 149 patients were initially enrolled. Of these, 140 patients (520 lesions) completed the study according to protocol. Eight weeks after treatment, 86% of the AK lesions (74% of the patients) treated with 4-h patch application showed complete clearance. The complete clearance rates of lesions (patients) for the 2-, 1- and 0.5-h treatment arms were 73% (47%), 72% (50%) and 51% (24%), respectively. Statistically, the 4-h application was identified as the 'best treatment'. Patients with clearance seemed to experience local reactions to a greater extent than patients without clearance. Local reactions to study treatments did not exceed the expected range.
Conclusions:  The results of this first clinical efficacy study suggest excellent therapeutic outcomes with a single PD P 506 A PDT with a 4-h application.  相似文献   
49.
Abstract:  Multiphoton excited tissue fluorescence summarises the emission of all naturally occurring endogenous fluorescent bio-molecules with their often overlapping fluorescence spectra. Common fluorescence intensity measurements could not be utilised to distinguish between different fluorophores or metabolic states. To overcome this limitation, we investigated new procedures of selective melanin imaging and spectral fluorescence lifetime imaging in combination with high resolution multiphoton laser tomography. Overall 46 melanocytic lesions of human skin were analysed. We suggested that fluorescence light, detected in such a way, may yield additional information for melanoma diagnostics. Remarkable differences in lifetime behaviour of keratinocytes in contrast to melanocytes were observed. Fluorescence lifetime distribution was found in correlation with the intracellular amount of melanin. Spectral analysis of melanoma revealed a main fluorescence peak around 470 nm in combination with an additional peak close to 550 nm throughout all epidermal layers. Excitation at 800 nm shows a selectively observable fluorescence of melanin containing cells and offers the possibility of cell classification. Procedures of selective imaging as well as spectral fluorescence lifetime imaging by means of multiphoton laser tomography support diagnostic decisions and may improve the process of non-invasive early detection of melanoma.  相似文献   
50.
Objective

To determine frequencies, interlaboratory reproducibility, clinical ratings, and prognostic implications of neural antibodies in a routine laboratory setting in patients with suspected neuropsychiatric autoimmune conditions.

Methods

Earliest available samples from 10,919 patients were tested for a broad panel of neural antibodies. Sera that reacted with leucine-rich glioma-inactivated protein 1 (LGI1), contactin-associated protein-2 (CASPR2), or the voltage-gated potassium channel (VGKC) complex were retested for LGI1 and CASPR2 antibodies by another laboratory. Physicians in charge of patients with positive antibody results retrospectively reported on clinical, treatment, and outcome parameters.

Results

Positive results were obtained for 576 patients (5.3%). Median disease duration was 6 months (interquartile range 0.6–46 months). In most patients, antibodies were detected both in CSF and serum. However, in 16 (28%) patients with N-methyl-d-aspartate receptor (NMDAR) antibodies, this diagnosis could be made only in cerebrospinal fluid (CSF). The two laboratories agreed largely on LGI1 and CASPR2 antibody diagnoses (κ = 0.95). The clinicians (413 responses, 71.7%) rated two-thirds of the antibody-positive patients as autoimmune. Antibodies against the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR), NMDAR (CSF or high serum titer), γ-aminobutyric acid-B receptor (GABABR), and LGI1 had ≥ 90% positive ratings, whereas antibodies against the glycine receptor, VGKC complex, or otherwise unspecified neuropil had ≤ 40% positive ratings. Of the patients with surface antibodies, 64% improved after ≥ 3 months, mostly with ≥ 1 immunotherapy intervention.

Conclusions

This novel approach starting from routine diagnostics in a dedicated laboratory provides reliable and useful results with therapeutic implications. Counseling should consider clinical presentation, demographic features, and antibody titers of the individual patient.

  相似文献   
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