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1.
Synkinesias secondary to nerve lesions and aberrant re-innervation are well-known phenomena especially after lesions of the facial nerve. Synkinesias can successfully be treated with botulinum toxin A (BTx A). Synkinesias of the cremaster muscle have not been described or treated to date. We present the case of a 62-year-old man who developed synkinesias of both cremaster muscles after extensive laparatomy for esophageal cancer. Treatment of synkinesias with various oral medications had been unsuccessful. Electromyography-guided injections of BTx A in both cremaster muscles (15 MU on the right and 10 on the left) led to significant symptom relief for an average of 8 weeks. We present the case including pre- and posttreatment video clips.  相似文献   
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Polyarteritis nodosa (PAN) presents mostly as a systemic disease with poor prognosis, rarely in an isolated form with a usually favorable outcome. Both forms may affect the male reproductive system and both forms have been associated with malignancies. We describe for the first time the occurrence of isolated PAN in the reproductive system combined with a mixed germ cell tumor of the testis in a 21-year-old man presenting with symptoms of chronic epididymitis. Two years after surgery he is without evidence of recurrence of either the tumor or PAN.  相似文献   
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PROBLEM: The choriocarcinoma cell line Jeg3 suppresses immunity in vitro by secretion of soluble factors like leukemia inhibitory factor suppressing leukocyte activation. The cells lack expression of classical human leukocyte antigen (HLA)-A and -B alleles but express some HLA-C, and non-classical HLA-G and -E. Upon binding to killing inhibitory receptor on natural killer (NK) cells, HLA-G prevents activation of cytolytic activity. We investigated whether Jeg3 cells are capable of immune stimulation after complementation with classical HLA and T cell costimulatory signal CD80. METHOD OF STUDY: Jeg3 cells were transduced to express HLA-A*0201 and/or CD80. Parental Jeg3 or transfectants Jeg3-A2, Jeg3-CD80 or Jeg3-CD80-A2 were used to stimulate allogeneic resting and activated peripheral blood lymphocytes (PBL). The different cell lines were loaded with a HLA-A2-restricted Epstein-Barr virus (EBV) recall antigen peptide epitope and antigen presenting ability was examined. T cell lines specific for Jeg3 and transfectants were generated from HLA-A2 matched and nonmatched donors and compared for expansion, phenotypes and cytolytic activity. RESULTS: While all Jeg3 cell lines induced only marginal proliferation of resting T cells, phytohemagglutinin (PHA)-activated T cells were stimulated by CD80 or CD80-A2 expressing Jeg3. Only the transfectant Jeg3-CD80-A2 was capable of specific T cell stimulation by EBV recall antigen presentation. T cell lines of HLA-A2 non-matched donors stimulated with the Jeg3 transfectants showed significant expansion only when HLA-A2 and the costimulus CD80 were present. T cells from HLA-A2 positive donors did not expand significantly or differentially. No NK cells grew under any condition. In Jeg3-CD80-A2 stimulated T cells lines CD8+ cells expanded preferentially. These T cells exerted cytolytic activity toward all Jeg3 cell lines. CONCLUSION: Our data suggest that, in spite of immunosuppressive mechanisms, proliferative and cytolytic T cell responses are induced by Jeg3 cells when classical HLA- and/or costimulatory signals are present on the cells.  相似文献   
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The general characteristics of these telemetrically recorded neurons of dorsal raphe, such as firing rate under nembutal anesthesia, reaction to illumination changes or acoustic stimuli were comparable to those in the literature. The firing rate of the dorsal raphe neurons increased during defensive encounters (+51%±29% S.D.; p<0.005) and defensive fights (+113%±91% S.D.; p<0.02) as compared to the neuronal activity of the undisturbed resting animal. The fearful interaction of the animal with the experimenter led to the strongest increase in the firing rate (+187%±114% S.D.; p<0.002) in all animals tested. The offensive animal showed decreased neuronal activity during offensive encounters (?21%±13% S.D.; p<0.02) and offensive fights (?42%±17%S.D.; p<0.05) as compared with the neuronal activity of the undisturbed resting animal. These findings indicate the crucial importance of the animals appraisal of the situational contex for the activity of dorsal raphe neurons.  相似文献   
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In order to investigate the role of the ferric uptake regulator Fur in the porcine lung pathogen Actinobacillus pleuropneumoniae, we constructed an isogenic in-frame deletion mutant, A. pleuropneumoniae Deltafur. This mutant showed constitutive expression of transferrin-binding proteins, growth deficiencies in vitro, and reduced virulence in an aerosol infection model.  相似文献   
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A molecular oscillator that controls the expression of cyclic genes such as lunatic fringe (Lfng) in the presomitic mesoderm has been shown to be coupled with somite formation in vertebrate embryos. To address the functional significance of oscillating Lfng expression, we have generated transgenic mice expressing Lfng constitutively in the presomitic mesoderm in addition to the intrinsic cyclic Lfng activity. These transgenic lines displayed defects of somite patterning and vertebral organization that were very similar to those of Lfng null mutants. Furthermore, constitutive expression of exogenous Lfng did not compensate for the complete loss of cyclic endogenous Lfng activity. Noncyclic exogenous Lfng expression did not abolish cyclic expression of endogenous Lfng in the posterior presomitic mesoderm (psm) but affected its expression pattern in the anterior psm. Similarly, dynamic expression of Hes7 was not abolished but abnormal expression patterns were obtained. Our data are consistent with a model in which alternations of Lfng activity between ON and OFF states in the presomitic mesoderm prior to somite segmentation are critical for proper somite patterning, and suggest that Notch signaling might not be the only determinant of cyclic gene expression in the presomitic mesoderm of mouse embryos.  相似文献   
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In vivo and in vitro studies have demonstrated both promise and current limitations in tissue engineering of fat. Herein, we report the establishment of a well-defined three-dimensional (3-D) in vitro model useful for systematic investigations of 3-D adipogenesis. Polyglycolic acid fiber meshes were dynamically seeded with 3T3-L1 preadipocytes; subsequently, cell-polymer constructs were hormonally induced and cultivation under three different conditions was evaluated. Regarding tissue coherence and intracellular lipid content, culture of cell-polymer constructs either dynamically in well plates or in stirred bioreactors yielded similar results, which were distinctly improved compared with static conditions in well plates. At the protein and mRNA levels, significantly increased expression of genes characteristic for a mature adipose phenotype was demonstrated for constructs dynamically cultured in well plates, as compared with static conditions. Furthermore, investigation of lipolysis under stimulating and inhibiting conditions demonstrated functionality of the dynamically differentiated constructs. Using dynamic culture conditions, the presented in vitro model system is suggested as a valuable tool serving both fat tissue engineering and basic research by facilitating investigations of tissue-inherent features not possible under conventional 2-D culture conditions.  相似文献   
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The immunophilin receptors implicated in generating the neurotrophic effects of FK506 and rapamycin (RM) are unknown. Our studies are directed at (1) characterizing the effects of FK506 and RM on human fetal neurons and glia (2) revealing the role played by the immunophilin FKBP receptors and downstream effectors in mediating the effects of FK506 and RM on human brain cells and (3) clarifying the role of immunophilins (IP) in the normal and degenerating human brain. These studies provide the basis for the implementation of the FDA-approved immunophilin ligands (IPL) in the pharmacologic treatment of Parkinson's disease (PD). Additionally, they establish a potential link to pathogenetic and repair mechanisms associated with neurodegeneration and propose FKBP12 and FKBP52 as substrates that can be targeted by future drug design endeavors. Our studies also show for the first time that the immunophilin FKBP is present in the human brain and that its levels are altered in the brain of patients with neurodegenerative diseases. The increased levels of FKBP12 in neurons situated in areas of degeneration suggest that it may become a novel marker of pathology. Although the precise role of this immunophilin in the normal and degenerating brain awaits further clarification, this study suggests that FKBP might play a role in neuroprotection against abnormal protein aggregation, as well as participate in axonal transport and synaptic vesicle assembly. The rotamase activity of FKBP is likely to underlie these functions. If this hypothesis is confirmed, therapeutic attempts using rotamase activity-inhibiting immunophilin ligand administration in neurodegenerative disease patients need to be carefully designed.  相似文献   
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