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21.
Homologous recombination was used to generate a number of mutants of serogroup B Neisseria meningitidis B16B6 with the following characteristics: (i) an inability to bind human or porcine transferrin because of loss of both transferrin binding proteins (Tbp) A and B [strain B16B6(Str(r))/tbpA(-)B(-)] and (ii) an ability to bind porcine transferrin but not human transferrin [strain B16B6(Str(r))/tbpA(ap)B(ap)] due to replacement of the meningococcal Tbp with the Tbp of Actinobacillus pleuropneumoniae. During construction of the B16B6(Str(r))/tbpA(ap)B(ap) strain, transformants expressing only TbpA or TbpB of A. pleuropneumoniae were isolated [strains B16B6(Str(r))/tbpA(ap)B(-) and B16B6(Str(r))/tbpA(-)B(ap)]. Expression of the A. pleuropneumoniae Tbp in N. meningitidis B16B6 was iron regulated and expressed under the control of the meningococcal promoter. The relative abilities of the meningococcal transformants to bind porcine transferrin were in the order B16B6(Str(r))/tbpA(ap)B(ap) > B16B6(Str(r))/tbpA(ap)B(-) > B16B6(Str(r))/tbpA(-)B(ap). Of these transformants, only B16B6(Str(r))/tbpA(ap)B(ap) could grow in the presence of porcine transferrin as the sole iron source, achieving a growth rate similar to that of the B16B6 parent strain in the presence of human transferrin.  相似文献   
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We tested 413 water buffalo cows (142 cases and 271 controls) for the presence of anti-Brucella abortus antibodies (by the skin test, the agglutination test, and the complement fixation test) and the Nramp1 genotype (by capillary electrophoresis). Four alleles (Nramp1A, -B, -C, and -D) were detected in the 3' untranslated region of the Nramp1 gene. The BB genotype was represented among only controls, providing evidence that this genotype confers resistance to Brucella abortus. The monocytes from the BB (resistant) subjects displayed a higher basal level of Nramp1 mRNA and a lower number of viable intracellular bacteria than did the monocytes from AA (susceptible) subjects. The higher basal level of the antibacterial protein Nramp1 most probably provides the BB animals with the possibility of controlling bacteria immediately after their entry inside the cell.  相似文献   
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Constitutive bcl-2 overexpression increases the tumorigenic and metastatic potential of doxorubicin-resistant, estrogen-independent, MCF-7 ADR human breast cancer cells. We evaluated the sensitivity to taxanes (paclitaxel, docetaxel and IDN 5109) of 2 bcl-2-overexpressing MCF-7 ADR clones and control neomycin-transfected MCF-7 ADR neo cells. The 2 bcl-2-overexpressing MCF-7 ADR clones were relatively resistant to all 3 taxanes, whereas the MCF-7 ADR neo cells were relatively resistant to paclitaxel and docetaxel, but sensitive to IDN 5109. We found that both MCF-7 ADR neo and bcl-2-overexpressing MCF-7 ADR clones express high levels of the epidermal growth factor receptor (EGFR) and its ligand, transforming growth factor-alpha (TGF-alpha). Therefore, we tested the growth inhibitory effect of ZD1839 (Iressa, AstraZeneca, Macclesfield, UK), an orally active, selective EGFR tyrosine kinase inhibitor (EGFR-TKI) that is in clinical development. ZD1839 inhibited the growth in soft agar of all 3 clones in a dose-dependent manner (IC(50) of approximately 0.1 microm). This effect was accompanied by a dose-dependent inhibition of EGFR tyrosine autophosphorylation and of the production of TGF-alpha, basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF). To determine whether the blockade of EGFR signaling might affect the sensitivity of bcl-2-overexpressing MCF-7 ADR cells to taxanes, cells were treated with ZD1839 in combination with paclitaxel, docetaxel or IDN 5109, and dose-dependent cooperative growth inhibition as well as apoptosis potentiation were observed. Combined treatment with IDN 5109 and ZD1839 also resulted in a significant inhibition of bcl-2 expression in bcl-2-overexpressing MCF-7 ADR cells. These results demonstrate the ability of ZD1839 to overcome taxane resistance in a model of hormone-independent, multidrug-resistant, human breast cancer.  相似文献   
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A clinical case of neuroma resulting from an amputation which occurred following parotid surgery is reported. The present paper discusses the importance of differential diagnosis relating to this pathology and the surgical techniques that may contribute to setting a limit on its onset. Traumatic neuroma is a possible complication of parotid surgery together with motor deficiencies and Frey's syndrome and the less frequent salivary fistulas. It may also occur following oncological or plastic-reconstructive surgery. During parotidectomy operations, section of the great auricular nerve may be required to facilitate access to the parotid region. This manoeuvre may, however, also be associated with the onset of a neuroma during a time period varying from 2 to 10 years, according to the various authors who have examined the subject. The laterocervical tumefaction associated with neuroma poses a number of diagnostic problems as it has to be differentiated from a likely relapse or possibly from more complex inflammatory or metastatic lymphnodal pathology. A correct clinical and diagnostic multidisciplinary approach is fundamental if the pathology is to be classified in the right way and contributes to alleviating a state of mental unease in the patient that is associated with the sudden appearance of the tumefaction. Sectioning the nervous trunk by means of thermocautery and its subsequent sinking below the main trunk of the sternocleidomastoid muscle, are simple surgical manoeuvres that are useful for preventing the onset of traumatic neuroma.  相似文献   
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Neuropilin-1/-2 (+33 NRPs), VEGF-A165 co-receptors, are over-expressed during cancer progression. Thus, NRPs targeted drug development is challenged using a multistep in silico/in vitro screening procedure. The first fully non-peptidic VEGF-A165/NRPs protein–protein interaction antagonist (IC50 = 34 μM) without effect on pro-angiogenic kinases has been identified (compound-1). This hit showed breast cancer cells anti-proliferative activity (IC50 = 0.60 μM). Compound-1 treated NOG-xenografted mice significantly exerted tumor growth inhibition, which is correlated with Ki-67low expression and apoptosis. Furthermore, CD31+/CD34+ vessels are reduced in accordance with HUVEC-tube formation inhibition (IC50 = 0.20 μM). Taking together, compound-1 is the first fully organic inhibitor targeting NRPs.  相似文献   
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A 33-year-old woman with a 2-year history of swelling and pain in her buttock and left thigh fluctuating with her menstrual cycle who was becoming progressively disabled was referred to the department of orthopedics. Magnetic resonance imaging (MRI) detected a left buttock lesion of 3 × 2 cm that was initially diagnosed as muscular-fiber laceration with associated hematoma. The worsening of her symptomatology required an ultrasound-guided biopsy of the lesion that revealed endometriosis. Laparoscopy showed the pelvis to be free of gross disease. Hormonal suppression by means of gonadotropin-releasing hormone analog therapy proved adequate in temporarily alleviating symptoms. A year later the patient underwent surgical excision of the buttock lesion, which was effective in alleviating her symptoms for a short period of 10 months. A 1-year follow-up MRI revealed several small endometriotic foci, located among piriformis and obturator internus muscle fibers, which were considered not suitable for surgical removal. The patient is currently on a drug regime for pain management. However, she has experienced permanent muscular damage on her left buttock including significant omolateral gluteus strength reduction, functional impairment (inability to rotate laterally or bend her left leg), and the assumption of an antalgic gait while walking. Because of impairment in her deambulation capability, total physical invalidity was agreed for her by the National Health Care Services.  相似文献   
30.
Bucello  Sebastiano  Annovazzi  Pietro  Ragonese  Paolo  Altieri  Marta  Barcella  Valeria  Bergamaschi  Roberto  Bianchi  Alessia  Borriello  Giovanna  Buscarinu  Maria Chiara  Callari  Graziella  Capobianco  Marco  Capone  Fioravante  Cavalla  Paola  Cavarretta  Rosella  Cortese  Antonio  De Luca  Giovanna  Di Filippo  Massimiliano  Dattola  Vincenzo  Fantozzi  Roberta  Ferraro  Elisabetta  Filippi  Maria Maddalena  Gasperini  Claudio  Grimaldi  Luigi Maria Edoardo  Landi  Doriana  Re  Marianna Lo  Mallucci  Giulia  Manganotti  Paolo  Marfia  Girolama Alessandra  Mirabella  Massimiliano  Perini  Paola  Pisa  Marco  Realmuto  Sabrina  Russo  Margherita  Tomassini  Valentina  Torri-Clerici  Valentina Liliana Adriana  Zaffaroni  Mauro  Zuliani  Cristina  Zywicki  Sofia  Filippi  Massimo  Prosperini  Luca 《Journal of neurology》2021,268(8):2922-2932
Journal of Neurology - To identify baseline factors associated with disease activity in patients with relapsing–remitting multiple sclerosis (RRMS) under teriflunomide treatment. This was an...  相似文献   
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