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31.
A major challenge in reconstructive surgery is flap ischemia, which might benefit from induction of therapeutic angiogenesis. Here we demonstrate the effect of an adeno-associated virus (AAV) vector delivering vascular endothelial growth factor (VEGF)165 in two widely recognized in vivo flap models. For the epigastric flap model, animals were injected subcutaneously with 1.5 x 10(11) particles of AAV-VEGF at day 0, 7, or 14 before flap dissection. In the transverse rectus abdominis musculocutaneous flap model, AAV-VEGF was injected intramuscularly. The delivery of AAV-VEGF significantly improved flap survival in both models, reducing necrosis in all treatment groups compared to controls. The most notable results were obtained by administering the vector 14 days before flap dissection. In the transverse rectus abdominis musculocutaneous flap model, AAV-VEGF reduced the necrotic area by >50% at 1 week after surgery, with a highly significant improvement in the healing process throughout the following 2 weeks. The therapeutic effect of AAV-VEGF on flap survival was confirmed by histological evidence of neoangiogenesis in the formation of large numbers of CD31-positive capillaries and alpha-smooth muscle actin-positive arteriolae, particularly evident at the border between viable and necrotic tissue. These results underscore the efficacy of VEGF-induced neovascularization for the prevention of tissue ischemia and the improvement of flap survival in reconstructive surgery.  相似文献   
32.
Creutzfeldt-Jakob disease (CJD), the most common human prion disease, includes sporadic (s) and familial (f) forms. Regardless of etiology, both forms are thought to share the pathogenic mechanism whereby the cellular prion protein (PrP(C)) converts into its pathogenic isoform (PrP(Sc)). While PrP(C) conversion is thought to be random in sCJD, conversion in fCJD is facilitated by the congenital presence of mutated PrP. Differences in PrP genotype (PRNP) and in conversion circumstances lead to PrP(Sc) with distinct characteristics that elicit different disease phenotypes. Here, we describe a case of fCJD with a substitution of histidine (H) for arginine (R) at codon 148 (R148H) and heterozygosity of the methionine/valine (M/V) polymorphic codon 129, with the 129M allele coupled with the mutation. The disease phenotype and all major characteristics of PrP(Sc) of fCJD(R148H) were virtually indistinguishable from those of sCJDMV2, which has features different from those of any other sCJD. Therefore, despite the differences in etiology, PRNP, and conversion process, the two forms of PrP(Sc) had similar characteristics. Furthermore, comparison of fCJD(R148H) with a recently reported case carrying R148H and homozygosity at codon 129 suggests that codon 129 coupled with the mutation as well as that located on the normal allele can modify major phenotypic and PrP(Sc) features of fCJD(R148H).  相似文献   
33.
We used a colorimetric polymerase chain reaction (PCR)-based assay in kit form to detect directly human immunodeficiency virus type 1 (HIV-1) proviral gag sequences in peripheral blood cells from 68 healthy blood donors, 51 subjects at risk for HIV infection, 122 patients with HIV-1 infection, 11 patients with indeterminate Western blot (immunoblot) results, 4 blood donors HIV-1 positive by enzyme immunoassay, and 13 children born to HIV-1-seropositive mothers. The results obtained in the blood donors and HIV-1-infected patients demonstrated the high degree of diagnostic specificity and sensitivity of the PCR method. HIV-1 infection was excluded in 10 of the 11 patients with indeterminate Western blot results and in all four enzyme immunoassay-positive blood donors. A diagnosis of HIV infection was ruled out by negative PCR results in 5 of 13 children from seropositive mothers, which excluded vertical transmission of the infection in these cases; these children were younger than 3 months and had positive serological results. Two at-risk patients with negative serological results had positive PCR results. All results were confirmed by conventional PCR. In conclusion, colorimetric PCR, which is commercially available in kit form, is an easy and reliable technique that can be used to detect proviral HIV-1 genomes in blood cells, and despite the limitations owing to HIV genome variability, it is useful in the clinical setting for the diagnosis of HIV infection in selected categories of patients.  相似文献   
34.
Aicardi syndrome (AIC) is a rare congenital neurodevelopmental disorder of unknown etiology, that affects almost exclusively females, originally characterized by corpus callosum agenesis, chorioretinal lacunae, and infantile spasms. The current diagnostic criteria also include qualitative facial features (prominent premaxilla, upturned nasal tip, decreased nasal bridge angle, sparse lateral eyebrows, and microphthalmia) that still need quantification. A three‐dimensional (3D) photogrammetric assessment of 11 Italian females, age 7–32 years, who satisfied AIC criteria, was performed. Linear distances and angles were computed from soft‐tissue facial landmarks coordinates. The z‐score values were calculated using data of 850 healthy reference females matched for age and compared by Mann–Whitney test (p < .01). Patients showed a shorter philtrum and right side orbital height (mean z‐scores: ?1.7, ?0.9), shorter superior, middle, and inferior facial depths (mean z‐scores: ?1.3, ?2.2, ?2.3), and a smaller length of mandibular ramus (mean z‐score: ?2.1); conversely, they showed larger nasal and lower facial widths, and lower facial convexity (mean z‐scores: 1.7, 1.4, 2.4). The inclinations of the orbit versus the true horizontal were increased bilaterally (mean z‐scores: 1.8, 1.1). Some common facial abnormalities were quantified in AIC patients using a noninvasive instrument. They may help clinicians in performing a definite AIC diagnosis in atypical or doubt cases.  相似文献   
35.
A 53-yr-old woman presented with a left upper quadrant abdominal mass attached to the body of the pancreas. Fine-needle aspiration (FNA) yielded cyst fluid containing numerous benign, mature squamous cells, keratin debris, and inflammatory cells. The diagnosis of dermoid cyst was subsequently rendered on the resected specimen. The cytologic and histologic features are presented. FNA cytology proves to be a valuable diagnostic adjunct in the preoperative evaluation of a patient with dermoid cyst of the pancreas.  相似文献   
36.
The frequencies of anti-interferon-beta (IFN-beta) antibody development reported to date in patients treated with different IFN-beta preparations are not readily comparable mainly because of differences in underlying diseases and assay methods. Thus, the frequency of neutralizing antibody (NAb) and binding antibody (BAb) development was analyzed in a sample of sera derived from a homogeneous group of relapsing-remitting multiple sclerosis (RRMS) patients treated with different IFN-beta preparations. The frequency of developing NAb and BAb to IFN-beta varied according to the IFN-beta given. Specifically, the NAb seroconversion frequency was significantly higher in patients treated with Betaferon, Schering AG, Berlin, Germany (31.3%) than in patients treated with both preparations of recombinant IFN-beta 1a (Rebif, Serono, Geneva, Switzerland [7.4%] or Avonex, Biogen, Cambridge, MA [6.3%]). Analysis of BAb seroconversion frequency in the same patients revealed that different IFN-beta preparations may also have different capability to induce BAb development and that BAb are produced during IFN-beta therapy at a significantly higher rate than NAb. Our main conclusion is that different human IFN-beta preparations may possess different immunogenicities, leading to varying frequency of development of antibody to IFN-beta in RRMS.  相似文献   
37.
Cancer predisposition syndromes (CPS) result from germline pathogenic variants, and they are increasingly recognized in the etiology of many pediatric cancers. Herein, we report the genetic/genomic analysis of 40 pediatric patients enrolled from 2016 to 2018. Our diagnostic workflow was successful in 50% of screened cases. Overall, the proportion of CPS in our case series is 10.9% (20/184) of enrolled patients. Interestingly, 12.5% of patients achieved a conclusive diagnosis through the analysis of chromosomal imbalance. Indeed, we observed germline microdeletions/duplications of regions encompassing cancer-related genes in 50% of patients undergoing array-CGH: EIF3H duplication in a patient with infantile desmoplastic astrocytoma and low-grade Glioma; SLFN11 deletion, SOX4 duplication, and PARK2 partial deletion in three neuroblastoma patients; a PTPRD partial deletion in a child diagnosed with glioblastoma multiforme. Finally, we identified two cases due to DICER1 germline mutations.  相似文献   
38.
Increased expression of TRAIL in membrane-bound and soluble form in patients with systemic lupus erythematosus (SLE) has been previously reported. In this study, we characterized the upregulation of T-cell-associated and soluble TRAIL (sTRAIL) in vivo and the modulation of TRAIL expression and soluble protein release in vitro following T cell activation and IFNalpha exposure. The expression of membrane-bound TRAIL as determined by flow cytometry was higher on CD4(+) and CD8(+) T cells from lupus patients compared to controls, particularly on activated CD69(+)CD8(+) T cells. Similarly, sTRAIL levels determined by ELISA were significantly elevated in serum from patients with active SLE and correlated with levels of IFNalpha. In vitro, both T-cell-associated and sTRAIL were maximally induced by T cell activation plus IFNalpha in patients and controls. By Western blot analysis, sTRAIL was detected in sera in both the monomeric and multimeric, functional form. Both forms of TRAIL were functional in vitro as determined by Annexin V staining and (51)Cr release assay but the apoptotic activity of membrane TRAIL was 2.5-fold higher compared to that of sTRAIL. These results indicate that IFNalpha-induced enhancement of TRAIL expression and of TRAIL-mediated apoptosis may amplify the abnormal apoptotic process in SLE.  相似文献   
39.
We evaluated the efficacy of enrofloxacin, alone or combined with metronidazole, against Leishmania infantum. The in vitro activity of this fluoroquinolone was assessed using two different methods: a direct test aimed at assessing the drug activity on the parasite, and an indirect test aimed at evaluating the drug effect on macrophage killing, lymphomonocyte activation and nitric oxide production. An in vivo test was also performed on 36 dogs with leishmaniasis, subdivided into three groups, one treated with enrofloxacin, another with enrofloxacin plus metronidazole, and a control group with meglumine antimoniate. The direct test did not show any action of enrofloxacin on the parasite, while the indirect testing showed an enhancement of macrophage killing and an increase in nitric oxide production. These findings show that enrofloxacin does not exert a direct anti-leishmanial activity in vitro. However, on the basis of the positive immunostimulation results shown in vitro and the clinical improvement, particularly of the cutaneous lesions, obtained in several dogs in the in vivo trial, the use of enrofloxacin in association with a specific anti-leishmanial drug can be proposed in the therapeutic protocol of canine leishmaniasis.  相似文献   
40.
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