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61.
Canine distemper virus (CDV) infection is a primary threat affecting a wide number of carnivore species, including wild animals. In January 2013, two carcasses of Apennine wolves (Canis lupus) were collected in Ortona dei Marsi (L''Aquila province, Italy) by the local Veterinary Services. CDV was immediately identified either by RT-PCR or immunohistochemistry in lung and central nervous tissue samples. At the same time, severe clinical signs consistent with CDV infection were identified and taped (Videos S1S3) from three wolves rescued in the areas surrounding the National Parks of the Abruzzi region by the Veterinary Services. The samples collected from these symptomatic animals also turned out CDV positive by RT-PCR. So far, 30 carcasses of wolves were screened and CDV was detected in 20 of them. The sequencing of the haemagglutinin gene and subsequent phylogenetic analysis demonstrated that the identified virus belonged to the CDV Arctic lineage. Strains belonging to this lineage are known to circulate in Italy and in Eastern Europe amongst domestic dogs. To the best of our knowledge this is the first report of CDV Arctic lineage epidemics in the wild population in Europe.  相似文献   
62.
Parathyroid hormone-related protein (PTH-rP), a protein produced by prostate carcinoma and other epithelial cancers, is a key agent in the development of bone metastases. We investigated whether the protein follows the self-tolerance paradigm or can be used as a target Ag for anticancer immunotherapy by investigating the immunogenicity of two HLA-A(*)02.01-binding PTH-rP-derived peptides (PTR-2 and -4) with different affinity qualities. PTH-rP peptide-specific CTL lines were generated from the PBMC of two HLA-A(*)02.01(+) healthy individuals, stimulated in vitro with PTH-rP peptide-loaded autologous dendritic cells and IL-2. The peptide-specific CTLs were able to kill PTH-rP(+)HLA-A(*)02.01(+) breast and prostate carcinoma cell lines. The two peptides were also able to elicit a strong antitumor PTH-rP-specific CTL response in HLA-A(*)02.01 (HHD) transgenic mice. The vaccinated mice did not show any sign of side effects due to cell-mediated autoimmunity or toxicity. In this study we describe two immunogenic and toxic-free PTH-rP peptides as valid candidates for the design of peptide-based vaccination strategies against prostate cancer and bone metastases from the most common epithelial malignancies.  相似文献   
63.
ABSTRACT: BACKGROUND: Salvinorin A (SA), the main active component of Salvia Divinorum, is a non-nitrogenous kappa opioid receptor (KOR) agonist. It has been shown to reduce acute pain and to exert potent antinflammatory effects. This study assesses the effects and the mode of action of SA on formalin-induced persistent pain in mice. Specifically, the SA effects on long-term behavioural dysfuctions and changes in neuronal activity occurring at spinal level, after single peripheral formalin injection, have been investigated. Moreover, the involvement of microglial and glial cells in formalin-induced chronic pain condition and in SA-mediated effects has been evaluated. RESULTS: Formalin induced a significant decrease of mechanical withdrawal threshold at the injected and contralateral paw as well as an increase in the duration and frequency, and a rapid decrease in the onset of evoked activity of the nociceptive neurons 7 days after formalin injection. SA daily treatment significantly reduced mechanical allodynia in KOR and cannabinoid receptor 1 (CB1R) sensitive manner. SA treatment also normalized the spinal evoked activity. SA significantly reduced the formalin-mediated microglia and astrocytes activation and modulated pro and anti-inflammatory mediators in the spinal cord. CONCLUSION: SA is effective in reducing formalin-induced mechanical allodynia and spinal neuronal hyperactivity. Our findings suggest that SA reduces glial activation and contributes in the establishment of dysfunctions associated with chronic pain with mechanisms involving KOR and CB1R. SA may provide a new lead compound for developing anti-allodynic agents via KOR and CB1R activation.  相似文献   
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The synthesis and characterization of a new class of DNA binding molecule exhibiting potent and selective anti-leukemic activity is described. The synthesis of an aminoacyl nucleolipid was developed from an efficient EEDQ coupling strategy, in which a series of seven bioconjugates were synthesized in yields of 53–78%. Guanosine bioconjugate 7, was used as building block for the synthesis of a target aminoacyl nucleolipid 14. Its GRP78 DNA binding affinity was confirmed by gel shift assay, CD spectroscopy, Tm measurements and dynamic light scattering experiments. Moreover, in a single dose (10 μM) screen against a panel of 60 cancer cell lines, aminoacyl nucleolipid 14 was found to selectively trigger greater than 90% cell death in a SR human leukemia cancer cell line. The reported aminoacyl nucleolipid represents a useful model for a new class of DNA binding molecules for the development of potent and selective anti-cancer agents.  相似文献   
66.
The p53 tumor suppressor protein is an important regulator of cell proliferation and apoptosis. p53 can be found in the nucleus and in the cytosol, and the subcellular location is key to control p53 function. In this work, we found that a widely used monoclonal antibody against p53, termed Pab 1801 (Pan antibody 1801) yields a remarkable punctate signal in the cytoplasm of several cell lines of human origin. Surprisingly, these puncta were also observed in two independent p53-null cell lines. Moreover, the foci stained with the Pab 1801 were present in rat cells, although Pab 1801 recognizes an epitope that is not conserved in rodent p53. In contrast, the Pab 1801 nuclear staining corresponded to genuine p53, as it was upregulated by p53-stimulating drugs and absent in p53-null cells. We identified the Pab 1801 cytoplasmic puncta as P Bodies (PBs), which are involved in mRNA regulation. We found that, in several cell lines, including U2OS, WI38, SK-N-SH and HCT116, the Pab 1801 puncta strictly colocalize with PBs identified with specific antibodies against the PB components Hedls, Dcp1a, Xrn1 or Rck/p54. PBs are highly dynamic and accordingly, the Pab 1801 puncta vanished when PBs dissolved upon treatment with cycloheximide, a drug that causes polysome stabilization and PB disruption. In addition, the knockdown of specific PB components that affect PB integrity simultaneously caused PB dissolution and the disappearance of the Pab 1801 puncta. Our results reveal a strong cross-reactivity of the Pab 1801 with unknown PB component(s). This was observed upon distinct immunostaining protocols, thus meaning a major limitation on the use of this antibody for p53 imaging in the cytoplasm of most cell types of human or rodent origin.  相似文献   
67.
Aza-glycine has been incorporated into peptide mimics as a tool for studying the active conformation and characterizing structure-function relationships for activity. Side reactions, such as intramolecular cyclizations to form hydantoins and oxadiazalones, have, however, inhibited efforts to make activated aza-Gly residues in solution using carbamate protection. Herein, we describe efficient incorporation of aza-glycine into aza-peptides using diphenyl hydrazone protection. Hydrazone acylation with p-nitrobenzyl chloroformate provided the protected aza-Gly activated ester, which was used to acylate a set of amino ester and amino acids to provide aza-Gly-Xaa aza-dipeptide fragments for peptide synthesis. Removal of the hydrazone protection was performed under acidic conditions to provide the hydrochloride salt of the aza-Gly residue for subsequent elongation of the aza-peptide chain using standard coupling conditions. A proof of concept for the use of benzophenone protection has been established by the synthesis of an aza-peptide analog of a potent activator of caspase 9 in cancer cells.  相似文献   
68.
The efficiency of a series of well-known coupling reagents (TBTU, HATU, and PyBOP) and of new in situ activating reagents (TCTU, HCTU, and DMTMM) was compared by synthesizing the 65–74 fragment of the Acyl Carrier Protein (H-Val-Gln-Ala-Ala-Ile-Asp-Tyr-Ile-Asn-Gly-NH2), containing `a difficult sequence', as a test peptide, in a multiple peptide synthesizer. The longer sequence rMOG(35–55) was also synthesized. It was clear that the aminium salts are more efficient than the phosphonium salt (PyBOP) and that the new 6Cl-HOBt based reagents (HCTU and particularly TCTU) are very efficient, while DMTMM appeared to be not suitable for SPPS.  相似文献   
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70.
Requests for laboratory tests are among the most relevant additional tools used by physicians as part of patient''s health problemsolving. However, the overestimation of complementary investigation may be linked to less reflective medical practice as a consequence of a poor physician-patient communication, and may impair patient-centered care. This scenario is likely to result from reduced consultation time, and a clinical model focused on the disease. We propose a new medical intervention program that specifically targets improving the patient-centered communication of laboratory tests results, the core of bioinformation in health care. Expectations are that medical students training in communication skills significantly improve physicians-patient relationship, reduce inappropriate use of laboratorial tests, and raise stakeholder engagement.  相似文献   
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