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991.
992.
Stefanie Beelte Rainer Haas Ulrich Germing und Paul-Josef Jansing 《Medizinische Klinik》2008,103(8):553-560
BACKGROUND AND PURPOSE: Benzene-caused hematologic diseases can be recognized as occupational diseases (ODs) if they fulfill the legal requirements specified under No. 1303 of the appendix of the German ordinance on ODs. The aim of this study is to analyze the most important criteria that determined whether these diseases were recognized or rejected as ODs according to No. 1303 in 2006. METHODS: In 2006, 70 suspected cases of OD No. 1303 reported in North Rhine-Westphalia were examined in terms of diagnosis, notifiers, cumulative benzene exposures, professions, coexposures, delays in notification, latency periods, interim periods, and recognition criteria. RESULTS: 70 benign and malignant diseases of myeloid and lymphoid origin were reported as suspected ODs, among them 41 B-cell non-Hodgkin's lymphomas (B-cell NHL). Latency periods ranged between 14 and 57 years (median 37; mean 36.3+/-11.4; n=45), estimated cumulative benzene exposures varied from 0 to 144 ppm-years (median 12; mean 11.4+/-22.8; n=59). Four of 70 suspected cases were recognized as OD No. 1303. In 37 cases (52.9%), the nature of the disease was assessed as being nontypical of OD No. 1303, in 50 cases (71.4%), no sufficient benzene exposure could be found. Mature-cell NHL and Hodgkin's lymphoma were not recognized as OD. Cumulative benzene exposures相似文献
993.
Brandenburg LO Varoga D Nicolaeva N Leib SL Wilms H Podschun R Wruck CJ Schröder JM Pufe T Lucius R 《Journal of neuropathology and experimental neurology》2008,67(11):1041-1054
Antimicrobial peptides are intrinsic to the innate immune system in many organ systems, but little is known about their expression in the central nervous system. We examined cerebrospinal fluid (CSF) and serum from patients with active bacterial meningitis to assess antimicrobial peptides and possible bactericidal properties of the CSF. We found antimicrobial peptides (human cathelicidin LL-37) in the CSF of patients with bacterial meningitis but not in control CSF. We next characterized the expression, secretion, and bactericidal properties of rat cathelin-related antimicrobial peptide, the homologue of the human LL-37, in rat astrocytes and microglia after incubation with different bacterial components. Using real-time polymerase chain reaction and Western blotting, we determined that supernatants from both astrocytes and microglia incubated with bacterial component supernatants had antimicrobial activity. The expression of rat cathelin-related antimicrobial peptide in rat glial cells involved different signal transduction pathways and was induced by the inflammatory cytokines interleukin 1beta and tumor necrosis factor. In an experimental model of meningitis, infant rats were intracisternally infected with Streptococcus pneumoniae, and rat cathelin-related antimicrobial peptide was localized in glia, choroid plexus, and ependymal cells by immunohistochemistry. Together, these results suggest that cathelicidins produced by glia and other cells play an important part in the innate immune response against pathogens in central nervous system bacterial infections. 相似文献
994.
Dziewas R Hopmann B Humpert M Ritter M Dittrich R Schäbitz WR Ringelstein EB Nabavi DG Young P 《Neurological research》2008,30(6):645-648
BACKGROUND: In non-stroke patients, the severity of sleep apnea (SA) is known to be frequently related to the sleeping position, a condition called positional SA. In the present study, we investigated whether in acute stroke the occurrence of apneas was related to the positioning of patients, and whether a similar finding could be observed after rehabilitation. With the purpose of identifying patients potentially being in need of a SA treatment beyond rehabilitation, we furthermore looked for epidemiologic and clinical parameters being related to persistent SA 6 months after stroke. PATIENTS AND METHODS: Fifty-five acute stroke patients underwent cardiorespiratory polygraphy within 72 hours after onset of neurological symptoms and after 6 months. Apart from the total AHI (AHITOT), the AHI with the patient in supine position and the AHI with the patient in other positions were determined. In all patients, demographic data, NIH-stroke scale score and cumulative vascular risk factors were assessed. RESULTS: In the initial sleep study, 78% of patients had an AHI>or=10/h, of whom 65% fulfilled the criteria of positional SA. On follow-up, the incidence of SA declined to 49% with positional SA being present in 33%. Multivariate logistic regression analysis identified AHITOT on admission [OR=1.07 (1.002-1.13)] and cumulative vascular risk factors [OR=3.48 (1.34-9.05)] as independent predictors of persistent SA 6 months after stroke. CONCLUSION: According to our results, positional SA is a predominant feature in acute stroke and its incidence decreases significantly during the following months. These findings may have implications for SA treatment in patients with acute stroke. 相似文献
995.
In vitro resistance of articular chondrocytes to 5-Aminolevulinic acid based photodynamic therapy 总被引:1,自引:0,他引:1
Egli RJ Di Criscio A Hempfing A Schoeniger R Ganz R Hofstetter W Leunig M 《Lasers in surgery and medicine》2008,40(4):282-290
OBJECTIVE: 5-Aminolevulinic acid based photodynamic therapy (5-ALA-PDT) has revealed promising results in the treatment of inflammatory joint diseases due to the sensitivity of inflamed synovial tissue. For 5-ALA-PDT to be safe and beneficial for intra-articular applications, resistance of chondrocytes is essential to prevent cartilage damage. As no data yet exist, the aim of the present study was to assess in vitro the response of the chondrocytes to 5-ALA-PDT and to compare with osteoblasts and synovial tissue derived cells. METHODS: Bovine articular chondrocytes, osteoblasts, and synovial cells were subjected to 5-ALA-PDT in cell culture. The PpIX accumulation and the function of the cells were assessed for up to 12 days. RESULTS: Bovine chondrocytes showed lower PpIX fluorescence upon incubation with 5-ALA (0.0-2.0 mM) for 4 hours as compared to osteoblasts and synovial cells suggesting a low PpIX accumulation. After incubation with 0.5 mM 5-ALA and application of light at a dose of 20 J/cm2, chondrocytes were functionally not affected (collagen type II and aggrecan mRNA, glycosaminoglycan synthesis) whereas a decrease in the proportion of viable cells was observed in osteoblasts and synovial cells (2+/-2% and 14+/-8%, respectively; chondrocytes 91+/-13%). Chondrocytes showed a 58% reduction of 5-ALA uptake using [3H]5-ALA as compared to osteoblasts and a lower mitochondrial content as assessed by the activity of the mitochondrial marker enzyme citrate synthase (9.2+/- 3.6 mU/mg protein) than osteoblasts (32.6+/-10.5 mU/mg) and synovial cells (60.0+/-10.8 mU/mg). The reduced uptake of 5-ALA and/or the low mitochondrial content, an adaptation to their in vivo environment and the site of PpIX synthesis, presumably explains the lower PpIX content in chondrocytes and their resistance against 5-ALA-PDT. CONCLUSION: 5-ALA-PDT might represent a treatment strategy in inflammatory joint diseases without endangering the cartilage function. However, further in vitro and in vivo experiments are required to confirm this data in the authentic environment of chondrocytes, the articular cartilage. 相似文献
996.
Numerous clinical and experimental studies have been published concerning platelet receptor polymorphism and their role in causing myocardial infarction at an earlier age. It is still unclear, however, whether these polymorphisms are a risk factor for other occlusive diseases such as those in visceral arteries. We report a case of a young woman with acute celiac artery thrombosis and multiple platelet receptor polymorphisms. In addition, the intraoperative exploration showed some evidence of a local vascular compression syndrome. The patient was successfully treated with a bypass procedure and combined anticoagulation. It seems that platelet receptor polymorphisms are a moderate risk factor for local artery thrombosis regardless of vascular region. The obligatory precondition is pre-existing vascular damage, such as that caused by a local compression syndrome. 相似文献
997.
The authors have developed a stereotactic device for use in rabbits that uses the plane at the base of the mandible combined with cranial sutures as an anatomical reference. The device was developed for a study designed to evaluate catheters for infection prophylaxis, and this required the implantation of silicone catheters along a reproducible trajectory through the lateral ventricle. Cadaver and atlas studies demonstrated consistent spatial relationships between intracranial structures and the surface plane on which the animals were resting during the surgery. This plane is formed by the 2 mandibular angles and the mandibular tip. The authors developed a stainless steel stereotactic device that uses this mandibular plane as well as the coronal and sagittal sutures as spatial references. Operations were performed in 60 animals using the stereotactic device, and postmortem dissections of the animals' brains demonstrated 78.6% accuracy of the trajectory within a tolerance of deviation of 5 degrees , and 94.6% accuracy within a tolerance of 10 degrees . The accuracy of the trajectory of the last 18 consecutively operated animals was constantly within a tolerance of 5 degrees . The device can be autoclaved and, since it is relatively simple and inexpensive to build, the authors manufactured 3 identical frames and used them alternately to operate under sterile conditions. The fast and pain-free head fixation minimized anesthesia-related risks. The authors' experiences suggest that the device is suitable for ventricular punctures and, dependant on the individual requirements of accuracy, other procedures that require "approximate" stereotactic guidance especially when a series of animals need to undergo operations quickly. 相似文献
998.
999.
BACKGROUND: A pancreas transplant alone (PTA) in a nonuremic patient with brittle diabetes mellitus remains a rare procedure because the tradeoff for insulin independence is lifelong immunosuppression. METHODS: Herein we report our results at the University of Minnesota of 513 PTAs from December 17, 1966, through December 31, 2006. Of these recipients, 87% had previously experienced hypoglycemic unawareness and 23% experienced coma and/or seizures. These transplants spanned four immunosuppressive eras: pre-cyclosporine A (pre-CsA) era (16%), CsA era (23%), tacrolimus (TAC) era (47%), and calcineurin-inhibitor (CNI)-free era (14%). RESULTS: The overall patient survival rate at 1 year posttransplant was about 95%; at 5 years, it was 90%. The pancreas graft survival rate at 1 year increased significantly from the pre-CsA era (31%) to the TAC era (75%), thanks to a significant decline in immunologic and technical failures. The CNI-free protocol, because of its high infection and hematologic infection rate, did not further improve outcome. Risk factors for subsequent kidney failure (13% at 5 years posttransplant) were serum creatinine levels>1.5 mg/dl at the time of the pancreas transplant and recipient age<30 years. CONCLUSIONS: A technically successful PTA is currently the only treatment option that allows nonuremic patients with brittle diabetes to become insulin-independent in the long term. 相似文献
1000.
Sauer R Sautter-Bihl ML Budach W Feyer P Harms W Souchan R Wollwiener D Kreienberg R Wenz F 《Cancer》2007,110(6):1187-1194
BACKGROUND: Breast-conserving surgery followed by whole-breast radiotherapy (WBRT) has become the standard treatment for the majority of patients with early breast cancer. Whereas the indications for systemic adjuvant treatment have continuously expanded, there is a tendency to restrict postoperative radiotherapy to accelerated partial breast irradiation (APBI) instead of WBRT. METHODS: The different techniques of APBI are described and their respective advantages or potential drawbacks outlined. Moreover, the results described in the literature are briefly reviewed as a basis for the consensus statements and recommendations of the German Society of Radiation Oncology, the German Society of Senology, and the Working Group for Gynecological Oncology of the German Cancer Society. RESULTS: The methods mainly used for APBI are: interstitial radiotherapy with multicatheter technique, intraoperative radiotherapy (IORT) using either electrons produced by linear accelerators or 50 kV x-rays (Intrabeam), the balloon-catheter technique (MammoSite), or 3D conformal external beam radiotherapy. These techniques have marked differences in dose distribution and homogeneity. The published range of local recurrence rates varies between 0% to 37%, the median follow-up from 8 to 72 months. CONCLUSIONS: To date, follow-up times mostly do not yet permit a definite judgment concerning the long-term effectiveness and side effects of APBI. The relevant societies in Germany support randomized clinical studies comparing APBI with WBRT in a well-defined subset of low-risk patients. However, the authors expressly discourage the routine use of APBI outside clinical trials. Until definite results show that APBI neither impairs therapeutic outcome nor cosmetic results, WBRT remains the gold standard in the treatment of early breast cancer. 相似文献