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991.
Alberto Grassi Cecilia Signorelli Francisco Urrizola Federico Raggi Luca Macchiarola Tommaso Bonanzinga Stefano Zaffagnini 《The Knee》2018,25(4):577-587
Background
Until now, there has been a lack of in vivo analysis of the correlation between bony morphological features and laxity values after an anterior cruciate ligament (ACL) injury.Methods
Forty-two patients who underwent ACL-reconstruction were enrolled. Static laxity was evaluated as: antero-posterior displacement and internal–external rotation at 30° and 90° of flexion (AP30, AP90, IE30, IE90) and varus–valgus rotation at 0° and 30° of flexion (VV0, VV30). The pivot-shift (PS) test defined the dynamic laxity. Using magnetic resonance imaging, we evaluated the transepicondylar distance (TE), the width of the lateral and medial femoral condyles (LFCw and MFCw) and tibial plateau (LTPw and MTPw), the notch width index (NWI) and the ratio of width and height of the femoral notch (N-ratio), the ratio between the height and depth of the lateral and medial femoral condyle (LFC-ratio and MFC-ratio), the lateral and medial posterior tibial slopes (LTPs and MTPs) and the anterior subluxation of the lateral and medial tibial plateau with respect to the femoral condyle (LTPsublx and MTPsublx).Results
Concerning the AP30, LTPs (P = 0.047) and MTPsublx (P = 0.039) were shown to be independent predictors while for the AP90 only LTPs (P = 0.049) was an independent predictor. The LTPs (P = 0.039) was shown to be an independent predictor for IE90 laxity, while for the VV0 test it was identified as the LFCw (P = 0.007).Conclusions
A higher antero-posterior laxity at 30° and 90° of flexion was found in those with a lateral tibial slope < 5.5°. 相似文献992.
Rossana Scutari Monica Faieta Roberta D’Arrigo Lavinia Fabeni Cristina Mussini Andrea Cossarizza Claudio Casoli Carlo Federico Perno Valentina Svicher Claudia Alteri Stefano Aquaro 《Virus genes》2018,54(4):493-501
The aim of this study is to evaluate the amino acid variability of HIV-1 Gp41, C2–V3, and Nef in a group of patients characterized by different disease progression rates. HIV-1 sequences were collected from 19 Long term non progressor patients (LTNPs), 9 slow progressors (SPs), and 11 rapid progressors (RPs). Phylogenetic trees were estimated by MEGA 6. Differences in amino acid variability among sequences belonging to the 3 groups have been evaluated by amino acid divergence, Shannon entropy analysis, and the number of amino acid mutations (defined as amino acid variations compared with HxB2). The involvement of amino acid mutations on epitope rich regions was also investigated. The population was mainly composed of males (74.3%) and HIV-1 subtype B strains (B: 92.32%, CRF_12BF, A1, C: 2.56% each). Viral load (log10 copies/mL) and CD4+T cell count (cells/mm3) were 3.9 (3.5–4.2) and 618 (504–857) in LTNPs, 3.3 (2.8–4.7) and 463 (333–627) in SPs, and 4.6 (4.3–5.3) and 201 (110–254) in RPs. Gp41 and C2–V3 amino acid divergence was lower in LTNP and SP strains compared to RPs (median value: 0.085 and 0.091 vs. 0.114, p?=?0.005 and 0.042) and a trend of lower variability was observed for Nef (p?=?0.198). A lower entropy value was observed at 10, 3, and 7 positions of Gp41, C2–V3, and Nef belonging to LTNPs and at 7, 3, and 1 positions of Gp41, C2–V3, and Nef belonging to SPs compared with RPs (p?<?0.05). Focusing on epitope rich regions, again a higher degree of conservation was observed in Gp41 and C2–V3 sequences belonging to LTNPs and SPs compared to those belonging to RPs. This study shows that the extent of amino acid variability correlates with a different HIV-1 progression rate. This variability also involves CTL epitope rich regions, thus suggesting its involvement in the immune escape process modulation. 相似文献
993.
De Luca A Vendittelli M Baldini F Di Giambenedetto S Trotta MP Cingolani A Bacarelli A Gori C Perno CF Antinori A Ulivi G 《Antiviral therapy》2004,9(4):583-593
OBJECTIVES: To evaluate whether fuzzy operators can be usefully applied to the interpretation of genotypic HIV-1 drug resistance by experts, and to improve the prediction of salvage therapy outcome by adapting interpretation rules of genotypic resistance on the basis of their association with virological response data. METHODS: We used a clinical dataset of 231 patients failing highly active antiretroviral therapy (HAART) and starting salvage therapy with baseline resistance genotyping and virological outcomes after 3 and 6 months. A set of rules predicting genotypic resistance was initially derived from an expert (ADL). Rules were implemented using a fuzzy logic approach and the virological outcomes dataset used for the training phase. The resulting algorithm was validated using a separate set of 184 selected patients by correlating the resulting predicted activity with observed virological response at 3 months. For comparison, the expert systems from the drug resistance group of the Agence Nationale de Recherches sur le SIDA (ANRS-AC11) and the algorithm from the Stanford's HIV drug resistance database (Stanford HIVdb) were evaluated on the same set. RESULTS: The starting algorithm had a correlation with virological outcomes of R2=0.06 (P=0.0001). After the training phase the correlation with virological outcomes increased to R2=0.19 (P<0.000001). In the validation set of patients, the activity of the salvage regimen predicted by the fuzzy algorithm was the only variable independently predictive of the 3-month viral load change even after adjusting by the activity predicted by the two expert systems and baseline viral load (for each 10% salvage regimen's activity increase, mean HIV RNA change from baseline: -0.27 log10 copies/ml; 95% CI -0.39, -0.15). CONCLUSION: Using fuzzy operators in a virological outcomes training database to implement a rules-based algorithm for genotypic resistance interpretation, significant improvements of outcomes prediction were obtained. The resulting algorithm showed an independent predictive capability of virological outcomes over that of two rules-based interpretation algorithms made by experts. Although the system was trained and validated on a limited number of cases, the approach deserves further evaluation. 相似文献
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996.
Several cases of symptomatic hemicrania continua (HC) have been reported. A 66‐year‐old man, suffering from migraine without aura, presented with a four month history of a new headache fulfilling the ICHD 3beta clinical criteria for HC. HC onset was strictly related to the use of transdermal nitroglycerine patch (TNP). In agreement with the cardiologist, TNP was discontinued and the headache promptly disappeared; symptoms reappeared within 6‐12 hours after nitroglycerine reintroduction. After permanent discontinuation of TNP, headache disappeared at one year follow‐up. To the best of our knowledge, this is the first report of the occurrence of an HC‐like headache related to TNP. 相似文献
997.
Induction of immune tolerance to coagulation factor IX antigen by in vivo hepatic gene transfer
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Mingozzi F Liu YL Dobrzynski E Kaufhold A Liu JH Wang Y Arruda VR High KA Herzog RW 《The Journal of clinical investigation》2003,111(9):1347-1356
Gene replacement therapy is an attractive approach for treatment of genetic disease, but may be complicated by the risk of a neutralizing immune response to the therapeutic gene product. There are examples of humoral and cellular immune responses against the transgene product as well as absence of such responses, depending on vector design and the underlying mutation in the dysfunctional gene. It has been unclear, however, whether transgene expression can induce tolerance to the therapeutic antigen. Here, we demonstrate induction of immune tolerance to a secreted human coagulation factor IX (hF.IX) antigen by adeno-associated viral gene transfer to the liver. Tolerized mice showed absence of anti-hF.IX and substantially reduced in vitro T cell responses after immunization with hF.IX in adjuvant. Tolerance induction was antigen specific, affected a broad range of Th cell subsets, and was favored by higher levels of transgene expression as determined by promoter strength, vector dose, and mouse strain. Hepatocyte-derived hF.IX expression induced regulatory CD4(+) T cells that can suppress anti-hF.IX formation after adoptive transfer. With a strain-dependent rate of success, tolerance to murine F.IX was induced in mice with a large F.IX gene deletion, supporting the relevance of these data for treatment of hemophilia B and other genetic diseases. 相似文献
998.
Pérez-Vázquez M Román F Aracil B Cantón R Campos J 《Antimicrobial agents and chemotherapy》2003,47(11):3539-3541
The in vitro activity of garenoxacin (BMS-284756) against 62 clinical Haemophilus influenzae isolates with different fluoroquinolone susceptibilities was determined by the microdilution susceptibility testing method and compared with the activities of other oral quinolones and nonquinolone oral antimicrobial agents. Cefixime presented the highest intrinsic activity (MIC at which 50% of the isolates tested were inhibited [MIC(50)], 0.01 microg/ml), followed by garenoxacin, moxifloxacin, and ciprofloxacin (MIC(50), 0.06 microg/ml), levofloxacin (MIC(50), 0.12 microg/ml), cefuroxime (MIC(50), 1.0 microg/ml), and amoxicillin-clavulanate (MIC(50), 1.0/0.5 microg/ml), amoxicillin (MIC(50), 2 microg/ml), azithromycin (MIC(50), 4 microg/ml), and erythromycin (MIC(50), 8 microg/ml). In strains with ciprofloxacin MICs of < or =0.06 microg/ml, ciprofloxacin and garenoxacin displayed similar MIC(50)s and MIC(90)s, one dilution lower than those of moxifloxacin and levofloxacin. For strains for which ciprofloxacin MICs were > or = 0.12 microg/ml, MIC(50)s were similar for the four quinolones tested, although garenoxacin presented the widest activity range (0.03 to 32 microg/ml) and the highest MIC at which 90% of the isolates tested were inhibited (16.0 microg/ml). For strains without amino acid changes in the quinolone resistance determining region (QRDR) of GyrA and ParC, garenoxacin MICs were < or =0.03 microg/ml; with a single amino acid change in GyrA, garenoxacin MICs were 0.06 to 0.12 microg/ml; with one amino acid change each in GyrA and ParC, garenoxacin MICs were 0.5 to 2.0 micro g/ml; one amino acid change in ParC combined with two amino acid changes in GyrA increased the MICs to > or = 4 microg/ml for all assayed quinolones. We conclude that garenoxacin has excellent activity against H. influenzae, although progressive acquired resistance was observed by step-by-step mutation in the QRDR of gyrA and parC. 相似文献
999.
Neural correlates of the emergence of consciousness of thirst 总被引:4,自引:0,他引:4
Egan G Silk T Zamarripa F Williams J Federico P Cunnington R Carabott L Blair-West J Shade R McKinley M Farrell M Lancaster J Jackson G Fox P Denton D 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(25):15241-15246
Thirst was induced by rapid i.v. infusion of hypertonic saline (0.51 M at 13.4 ml/min). Ten humans were neuroimaged by positron-emission tomography (PET) and four by functional MRI (fMRI). PET images were made 25 min after beginning infusion, when the sensation of thirst began to enter the stream of consciousness. The fMRI images were made when the maximum rate of increase of thirst occurred. The PET results showed regional cerebral blood flow changes similar to those delineated when thirst was maximal. These loci involved the phylogenetically ancient areas of the brain. fMRI showed activation in the anterior wall of the third ventricle, an area that is key in the genesis of thirst but is not an area revealed by PET imaging. Thus, this region plays as major a role in thirst for humans as for animals. Strong activations in the brain with fMRI included the anterior cingulate, parahippocampal gyrus, inferior and middle frontal gyri, insula, and cerebellum. When the subjects drank water to satiation, thirst declined immediately to baseline. A precipitate decline in intensity of activation signal occurred in the anterior cingulate area (Brodmann area 32) putatively related to consciousness of thirst. The intensity of activation in the anterior wall of the third ventricle was essentially unchanged, which is consistent with the fact that a significant time (15-20 min) would be needed before plasma Na concentration changed as a result of water absorption from the gut. 相似文献
1000.
Somatostatin analogs in vitro effects in a growth hormone-releasing hormone-secreting bronchial carcinoid 总被引:3,自引:0,他引:3
Zatelli MC Maffei P Piccin D Martini C Rea F Rubello D Margutti A Culler MD Sicolo N degli Uberti EC 《The Journal of clinical endocrinology and metabolism》2005,90(4):2104-2109
A 29-yr-old woman presented with acromegaly, pituitary gland enlargement, and an isolated pulmonary mass of 3.3 cm in diameter, which displayed a very high tracer uptake after OctreoScan. Plasma GHRH levels were markedly elevated. The patient underwent left lung upper lobectomy, and histopathology disclosed a bronchial atypical carcinoid. The tissue was examined for somatostatin (SRIH) receptor subtypes (SSTRs) 1-5 expression by RT-PCR. Cultured tumor cells were treated with SRIH, lanreotide (BIM-23014), or SRIH analogs selective for SSTR2 (BIM-23120), SSTR5 (BIM-23206), or SSTR1 (BIM-23926). GHRH was measured in the medium after 6 h, and cell viability was assessed after 48 h. RT-PCR analysis showed expression of SSTR1, -2, and -5. GHRH secretion was significantly reduced by SRIH (-50%), Lan (-35%), as well as by the SSTR2, SSTR5, and SSTR1 selective agonists (-55, -75, and -20%, respectively), whereas cell viability was not affected. Our data show SSTR expression in a GHRH-secreting bronchial carcinoid and provide evidence that, in vitro, selective SSTR activation differently inhibit ectopic GHRH secretion. These findings suggest that SSTR-specific SRIH analogs may be useful in the medical therapy of GHRH-secreting bronchial carcinoids. 相似文献