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1.
Background The role of the vagal nerve in the autonomic nervous system is widely well known. Recently, an additional function was revealed serving as a connector between the nervous and immune system. This connection is called the “cholinergic inflammatory pathway.” Through stimulation of the acetylcholine receptors located upon the macrophages, the “unspecific” immune system can be directly influenced. Methods The vagal nerve was completely transected directly posterior to its passage through the diaphragm. The effect of complete vagotomy was analyzed using a murine model of polymicrobial peritonitis (colon ascendens stent peritonitis, CASP). Survival and clinical course of vagotomized or sham-operated mice were analyzed in the CASP model. Results After CASP surgery, vagotomy led to a significantly increased mortality (64.7%) in comparison to sham-vagotomized animals (34%). No difference in the bacterial load of various tissues (lung, liver, spleen, blood, lavage fluid, and kidney) from septic animals with or without vagotomy was observed. Vagotomized animals reveal elevated serum cytokine levels (TNF, IL-6, IL-10, and MCP-1) 20 h after the induction of polymicrobial peritonitis. Conclusion The vagal nerve is therefore an important modulator of the immune system. W. Kessler and T. Traeger contributed equally to this work Best of Forum Papers presented at the Annual Meeting of the German Society of Surgery, 2–5 May 2006, Berlin, Germany  相似文献   
2.
Spinal epidural hematoma. Report of a case and review of the literature   总被引:3,自引:0,他引:3  
We report the case of a thoracic epidural hematoma at the T7-T9 level which occurred after placement of spinal epidural catheter for continuous anaesthesia in acute pancreatitis. The male patient felt a sudden back pain after six days of successful analgesia and became paraplegic 24 hours afterwards. An emergency laminectomy and removal of the hematoma were performed; however, the patient recovered only incompletely.We discuss the clinical signs and symptoms of spinal epidural hematoma as well as its diagnostics and therapy. The controversial views from the literature concernings its etiology are critically reviewed.  相似文献   
3.
Malunion and nonunion after fracture present many difficulties in trauma surgery. Selection of the best therapy and operative techique requires careful analysis of the complications. Hyperthrophic nonunion of the femur shaft is mostly best treated with locking reamed nails. Significant differences in torsions after nailing can be corrected by repositioning of the distal interlocking screws if recognized sufficiently early. After fracture healing an open rotation osteotomy is necessary; stabilization can be achieved by means of medullary nails or a condylar plate. How a malalignment of the bone axis is corrected depends on the position of a malunion, the functional deficit caused, and the biomechanical demands on the joint. Condylar plates can often solve the problems in this region. There are also guidelines for ¶the treatment of atrophic and infected nonunions (recommended procedures are ¶aggressive debridement, autologous cancellous bone graft, and biological osteosynthesis), but the treatment of individual cases requires a exhaustive knowledge of and experience in this special field. It is quite common for even well-established procedures to fail. When the bone is biologically reduced and this is the reason for malunion newly developed techniques of internal fixation can be applied. The less invasive stabilization system (LISS), combined with autologous cancellous bone grafting if necessary, can result in healing even in a worst-case scenario.  相似文献   
4.
A system proposed by Wing and coworkers for subtyping autistic individuals on the basis of social interaction is examined in 78 autistic, 39 atypical, and 32 nonautistic, developmentally disordered individuals. Clinical ratings and questionnaire data based on the proposed subtypology were employed. Clinicians were able to reliably group both autistic and nonautistic cases into the three subtypes; these subtypes were strongly related to IQ. Issues relating to the validity and utility of this subtypology are discussed.  相似文献   
5.
Osteomyelitis patients feel their social and professional existence is threatened. Health insurances are faced with total treatment costs for each patient with osteomyelitis, which can reach 500.000,00 EUR. We must therefore make every effort, from the first onset of infection, to prevent the condition from becoming chronic and thus keep the potential problems to patients and insurance companies to a minimum: once the condition has become chronic there is absolutely no guarantee that treatment will be successful. Treatment must start with the removal of absolutely all necrotic tissue – soft tissue and bone – and of all implants. As in tumor surgery, en bloc resection is best. Up to now there is still no means of determining the exact limits of the infection. The surgeons's personal experience with osteomyelitis is the most important factor both in the treatment of these cases and therefore in the containment of treatment costs. Bone reconstruction is attempted after the soft tissue defects have been treated, either by bone grafting (defect < 3 cm) or by segment transfer. Modern techniques of reconstruction surgery can yield quite good results even in chronic oxteomyelitis, providing management has been optimum throughout. Patients with osteomyelitis should therefore be treated in specialist hospitals.  相似文献   
6.
The aim of this functional magnetic resonance imaging study was to investigate differences in visuomotor control with increasing task complexity. Twelve right-handed volunteers were asked to perform their signature under different degrees of visual control: internally generated movement with closed eyes, signing with open eyes, tracking the line of the projected signature forwards, and tracking the line of the projected signature backwards. There was a gradual onset and disappearance of activation within a distributed network. Parietal, lateral and medial frontal brain areas were activated during all conditions, confirming the involvement of a parieto-frontal system. The weight of activation shifted with increasing task complexity. Internally generated movements activated predominantly the inferior parietal lobule and the ventral premotor cortex, as well as the rostral cingulate area, pre-supplementary motor area (pre-SMA) and SMA proper. Opening the eyes reduced SMA and cingulate activation and activated increasingly the occipito-parietal areas with higher task complexity. Visually guided movements produced an activation predominantly in the superior parietal lobule and dorsal premotor cortex. This study bridges human activation studies with the results of neurophysiological studies with monkeys. It confirms a gradual transition of visuomotor control with increasing task complexity within a distributed parieto-frontal network.  相似文献   
7.
Left ventricular infarction (AMI) was produced in experimental animals and the contractile response to -adrenergic and H2-histaminergic stimulation by isoproterenol and impromidine tested in the isolated perfused heart preparation. Adenylate cyclase activity as well as binding characteristics of [3H]-dihydroalprenolol ([3H]-DHA), [3H]-methyl-tiotidine ([3H]-TIOT) and [3H]-quinuclidinyl benzilate ([3H]-QNB) to cardiac 1-, H2- and cholinergic muscarinic receptors were determined in sarcolemmal membrane preparations of the right ventricle of the same hearts. In addition, an attempt was made to elucidate the therapeutic value of post-AMI treatment with impromidine in the presence and absence of-sympathomimetic, in contrast to administration of prenalterol and the conventional therapy with -sympathomimetic drugs, e.g. dobutamine. Three days post-AMI the dose-response curve for isoproterenol of right ventriculardP/dt max was significantly depressed, while the inotropic effect of impromidine was not impaired. Stimulation of adenylate cyclase activity by isoproterenol was reduced by 80% whereas impromidine and NaF stimulation rates were unaltered. Receptor-binding studies indicated a 90% loss and 10-times lowered affinity (K D) of the remaining -receptors while specific [3H]-TIOT- and [3H]-QNB-binding was unchanged.Administration of dobutamine increased mortality rates and extension of infarct size, led to a further decrease in contractile response to isoproterenol, induced complete insensitivity of adenylate cyclase to isoproterenol stimulation and caused pronounced additional reduction of number and affinity of [3H]-DHA-binding sites. In contrast, all above alterations were prevented by treatment with either prenalterol or combined administration of impromidine plus metoprolol. It is concluded, that these alterations in the non-ischemic, uninvolved myocardium post-AMI are the result of catecholamine-induced specific damage of sarcolemmal -receptors. Furthermore, treatment with H2-agonists in combination with -blocking agents may have beneficial effects, whereas conventional therapy with -sympathomimetic drugs tends to worsen the already depressed function of the -adrenergic stimulation mechanism.Supported by grants Ba 666/1 and Ba 666/2-2 from the Deutsche Forschungsgemeinschaft (DFG).Data presented in this paper are part of a doctoral thesis by Dr S.B. Felix.  相似文献   
8.
BACKGROUND: Binding of allergens with IgE to the IgE receptors on mast cells and basophils results in the release of inflammatory mediators as sulfidoleukotrienes (SLTs), triggering allergic cascades that result in allergic symptoms, such as asthma and rhinitis. OBJECTIVE: We sought to investigate whether anti-IgE (Oma-lizumab), a humanized monoclonal anti-IgE antibody, in addition to specific immunotherapy (SIT) affects the leukotriene pathway. METHODS: Ninety-two children (age range, 6-17 years) with sensitization to birch and grass pollens and with seasonal allergic rhinitis were included in a phase III, placebo- controlled, multicenter clinical study. All subjects were randomized to one of 4 treatment groups. Two groups subcutaneously received birch SIT and 2 groups received grass SIT for at least 14 weeks before the start of the birch pollen season. After 12 weeks of SIT titration, placebo or anti-IgE was added for 24 weeks. The primary clinical efficacy variable was symptom load (ie, the sum of daily symptom severity score and rescue medication score during pollen season). Blood samples taken at baseline and at the end of study treatment after the grass pollen season were used for separation of leukocytes in this substudy. After in vitro stimulation of the blood cells with grass and birch pollen allergens, SLT release (LTC4, LTD4, and LTE4) was quantified by using the ELISA technique. RESULTS: Before the study treatment, SLT release to birch and grass pollen exposure did not differ significantly among the 4 groups. Under treatment with anti-IgE + SIT-grass (n = 23), a lower symptom load occurred during the pollen season compared to placebo + SIT-grass (n = 24, P =.012). The same applied to both groups receiving birch SIT (n = 23 and n = 22, respectively; P =.03). At the end of treatment, the combination of anti-IgE plus grass SIT, as well as anti-IgE plus birch SIT, resulted in significantly lower SLT release after stimulation with the corresponding allergen (416 ng/L [5th-95th percentile, 1-1168] and 207 ng/L [1-860 ng/L], respectively) compared with placebo plus SIT (2490 ng/L [384-6587 ng/L], P =.001; 2489 ng/L [1-5670 ng/L], P =.001). In addition, treatment with anti-IgE was also followed by significantly lower SLT releases to the allergens unrelated to SIT (grass SIT: 300 ng/L [1-2432 ng/L] in response to birch allergen; birch SIT: 1478 ng/L [1-4593 ng/L] in response to grass pollen) in comparison with placebo (grass SIT: 1850 ng/L [1-5499 ng/L], P =.001; birch SIT: 2792 ng/L [154-5839 ng/L], P =.04]. CONCLUSION: Anti-IgE therapy reduces leukotriene release of peripheral leukocytes stimulated with allergen in children with allergic rhinitis undergoing allergen immunotherapy independent of the type of SIT allergen used.  相似文献   
9.
10.
Summary After the use of d,1-folinic acid (d,1-CHO-THF), pharmacokinetic measurements should take into account 1-CHO-THF and its metabolite 1-methyltetrahydrofolic acid (1-CH3-THF) as well as d-CHO-THF. For this purpose, we developed a simple and rapid assay by combining reversed-phase HPLC to determine total levels of d,1-CHO-THF and CH3-THF and chiral HPLC to separate the biologically active 1-CHO-THF from the inactive d-CHO-THF. We investigated the pharmacokinetics after short-term infusion of 300 mg d,1-CHO-THF in ten healthy volunteers. With a mean of 56.5 min, 1-CHO-THF exhibits a rapid body clearance of 222 ml/min, about 60% of which is caused by metabolism to CH3-THF and 40%, by renal excretion. CH3-THF has a terminal half-life of 208 min and a total body clearance of 88.9 ml/min, which is essentially the same as the renal clearance. Due to the lower clearance of CH3-THF, its AUC (2,132 M × min) exceeds that of 1-CHO-THF (1445 M × min) by approximately 50%. In contrast to that of the reduced 1-folates, the total body and renal clearance of d-CHO-THF is very low, with values of 13.2 and 12.9 ml/min, respectively. This results in a very high AUC of 24, 269 M × min, which is higher by factors of 17 and 11 than those of 1-CHO-THF and CH3-THF, respectively. The implications of the distinct kinetics of the reduced 1-folates and d-CHO-THF for the efficacy of folinic acid/5-fluorouracil therapy and adequate protocols for the treatment of advanced colorectal cancer are discussed.Abbreviations CH2-THF N-5,N-10-methylenetetnahydrofolic acid - CH3-THF N-5-methyltetrahydrofolic acid - CHO-THF N-5-formyltetrahydrofolic acid - 5-FU 5-fluorouracil - FBAL -fluoro--alanine - FUH2 dihydrofluorouracil - FUPA -fluoroureidopropionic acid Dedicated to Prof. Dr. W. Wilmanns on the occasion of his 60th birthdayThis study was carried out with the support of the Lederle Company, Wolfratshausen  相似文献   
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