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101.
Demarchi F Bertoli C Copetti T Tanida I Brancolini C Eskelinen EL Schneider C 《The Journal of cell biology》2006,175(4):595-605
Ubiquitously expressed micro- and millicalpain, which both require the calpain small 1 (CAPNS1) regulatory subunit for function, play important roles in numerous biological and pathological phenomena. We have previously shown that the product of GAS2, a gene specifically induced at growth arrest, is an inhibitor of millicalpain and that its overexpression sensitizes cells to apoptosis in a p53-dependent manner (Benetti, R., G. Del Sal, M. Monte, G. Paroni, C. Brancolini, and C. Schneider. 2001. EMBO J. 20:2702-2714). More recently, we have shown that calpain is also involved in nuclear factor kappaB activation and its relative prosurvival function in response to ceramide, in which calpain deficiency strengthens the proapoptotic effect of ceramide (Demarchi, F., C. Bertoli, P.A. Greer, and C. Schneider. 2005. Cell Death Differ. 12:512-522). Here, we further explore the involvement of calpain in the apoptotic switch and find that in calpain-deficient cells, autophagy is impaired with a resulting dramatic increase in apoptotic cell death. Immunostaining of the endogenous autophagosome marker LC3 and electron microscopy experiments demonstrate that autophagy is impaired in CAPNS1-deficient cells. Accordingly, the enhancement of lysosomal activity and long-lived protein degradation, which normally occur upon starvation, is also reduced. In CAPNS1-depleted cells, ectopic LC3 accumulates in early endosome-like vesicles that may represent a salvage pathway for protein degradation when autophagy is defective. 相似文献
102.
Changes in the Spoilage-Related Microbiota of Beef during Refrigerated Storage under Different Packaging Conditions 总被引:6,自引:2,他引:4
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Danilo Ercolini Federica Russo Elena Torrieri Paolo Masi Francesco Villani 《Applied microbiology》2006,72(7):4663-4671
The microbial spoilage of beef was monitored during storage at 5°C under three different conditions of modified-atmosphere packaging (MAP): (i) air (MAP1), (ii) 60% O2 and 40% CO2 (MAP2), and (iii) 20% O2 and 40% CO2 (MAP3). Pseudomonas, Enterobacteriaceae, Brochothrix thermosphacta, and lactic acid bacteria were monitored by viable counts and PCR-denaturing gradient gel electrophoresis (DGGE) analysis during 14 days of storage. Moreover, headspace gas composition, weight loss, and beef color change were also determined at each sampling time. Overall, MAP2 was shown to have the best protective effect, keeping the microbial loads and color change to acceptable levels in the first 7 days of refrigerated storage. The microbial colonies from the plate counts of each microbial group were identified by PCR-DGGE of the variable V6-V8 region of the 16S rRNA gene. Thirteen different genera and at least 17 different species were identified after sequencing of DGGE fragments that showed a wide diversity of spoilage-related bacteria taking turns during beef storage in the function of the packaging conditions. The countable species for each spoilage-related microbial group were different according to packaging conditions and times of storage. In fact, the DGGE profiles displayed significant changes during time and depending on the initial atmosphere used. The spoilage occurred between 7 and 14 days of storage, and the microbial species found in the spoiled meat varied according to the packaging conditions. Rahnella aquatilis, Rahnella spp., Pseudomonas spp., and Carnobacterium divergens were identified as acting during beef storage in air (MAP1). Pseudomonas spp. and Lactobacillus sakei were found in beef stored under MAP conditions with high oxygen content (MAP2), while Rahnella spp. and L. sakei were the main species found during storage using MAP3. The identification of the spoilage-related microbiota by molecular methods can help in the effective establishment of storage conditions for fresh meat. 相似文献
103.
Mazzarella T Cambiaghi V Rizzo N Pilla L Parolini D Orsenigo E Colucci A Modorati G Doglioni C Parmiani G Maccalli C 《Cancer immunology, immunotherapy : CII》2012,61(8):1169-1182
Tumor-infiltrating lymphocytes (TILs) have been successfully used for adoptive cell transfer (ACT) immunotherapy; however, due to their scarce availability, this therapy is possible for a limited fraction of cutaneous melanoma patients. We assessed whether an effective protocol for ex vivo T-cell expansion from peripheral blood mononuclear cells (PBMCs), suitable for ACT of both cutaneous and ocular melanoma patients, could be identified. PBMCs from both cutaneous and ocular melanoma patients were stimulated in vitro with autologous, irradiated melanoma cells (mixed lymphocyte tumor cell culture; MLTCs) in the presence of IL-2 and IL-15 followed by the rapid expansion protocol (REP). The functional activity of these T lymphocytes was characterized and compared with that of TILs. In addition, the immune infiltration in vivo of ocular melanoma lesions was analyzed. An efficient in vitro MLTC expansion of melanoma reactive T cells was achieved from all PBMC's samples obtained in 7 cutaneous and ocular metastatic melanoma patients. Large numbers of melanoma-specific T cells could be obtained when the REP protocol was applied to these MLTCs. Most MLTCs were enriched in non-terminally differentiated T(EM) cells homogeneously expressing co-stimulatory molecules (e.g., NKG2D, CD28, CD134, CD137). A similar pattern of anti-tumor activity, in association with a more variable expression of co-stimulatory molecules, was detected on short-term in vitro cultured TILs isolated from the same patients. In these ocular melanoma patients, we observed an immune infiltrate with suppressive characteristics and a low rate of ex vivo growing TILs (28.5% of our cases). Our MLTC protocol overcomes this limitation, allowing the isolation of T lymphocytes with effector functions even in these patients. Thus, anti-tumor circulating PBMC-derived T cells could be efficiently isolated from melanoma patients by our novel ex vivo enrichment protocol. This protocol appears suitable for ACT studies of cutaneous and ocular melanoma patients. 相似文献
104.
Silva JA Ferrucci DL Peroni LA Abrahão PG Salamene AF Rossa-Junior C Carvalho HF Stach-Machado DR 《Journal of cellular physiology》2012,227(6):2441-2450
Molecular mechanisms responsible for periodontal disease (PD) and its worsening in type 1 Diabetes Mellitus (DM1) remain unknown. Cytokine profile and expression levels of collagenases, Mmp14, and tissue inhibitors were determined, as were the numbers of neutrophils and macrophages in combined streptozotocin-induced DM1 and ligature-induced PD models. Increased IL-23 (80-fold) and Mmp8 expression (25-fold) was found in DM1. Ligature resulted in an IL-1β/IL-6 profile, increased expression of Mmp8, Mmp13, and Mmp14 (but not Mmp1), and transient expression of Timp1 and Reck in non-diabetics. PD in DM1 involved IL-1β (but not IL-6) and IL-23/IL-17, reduced IL-6 and IL-10, sustained Mmp8 and Mmp14, increased Mmp13 and reduced Reck expression in association with 20-fold higher counts of neutrophils and macrophages. IL-23 and Mmp8 expression are hallmarks of DM1. In association with the IL-1/IL-6 (Th1) response in PD, one found a secondary IL-17 (Th17) pathway in non-diabetic rats. Low IL-6/TNF-α suggest that the Th1 response was compromised in DM1, while IL-17 indicates a prevalence of the Th17 pathway, resulting in high neutrophil recruitment. Mmp8, Mmp13, and Mmp14 expression seems important in the tissue destruction during PD in DM1. PD-associated IL-1/IL-6 (Th1), IL-10, and Reck expression are associated with the acute-to-chronic inflammation transition, which is lost in DM1. In conclusion, IL-23/IL-17 are associated with the PD progression in DM1. 相似文献
105.
Norata GD Venu VK Callegari E Paloschi V Catapano AL 《Biochimica et biophysica acta》2012,1822(6):927-935
The reduced expression (haplodeficiency) of the main brain derived neurotrophic factor receptor, namely TrkB is associated with reduced atherosclerosis, smooth muscle cells accumulation and collagen content in the lesion. These data support the concept that brain derived neurotrophic factor of vascular origin may contribute to atherosclerosis. However, to date, no experimental approach was possible to investigate this issue due to the lethality of brain derived neurotrophic factor null mice. To overcome these limitations, we generated a mouse model with a conditional deletion of brain derived neurotrophic factor in endothelial cells (Tie-2 Cre recombinase) on an atherosclerotic prone background (apolipoprotein E knock out) and investigated the effect of conditional brain derived neurotrophic factor deficiency on atherosclerosis. Despite brain derived neurotrophic factor reduction in the vascular wall, mice with conditional deletion of brain derived neurotrophic factor did not develop larger atherosclerotic lesion compared to controls. Smooth muscle cell content as well as the distribution of total and fibrillar collagen was similar in the atherosclerotic lesions from mice with brain derived neurotrophic factor conditional deficiency compared to controls. Finally an extended gene expression analysis failed to identify pro-atherogenic gene expression patterns among the animal with brain derived neurotrophic factor deficiency. In spite of the reduced brain derived neurotrophic factor expression, similar atherosclerosis development was observed in the brain derived neurotrophic factor conditional deficient mouse compared to controls. These pieces of evidence indicate that endothelial derived-brain derived neurotrophic factor is not a pro-atherogenic factor and would rather suggest to investigate the role of other TrkB activators on atherosclerosis. 相似文献
106.
Gal N Malferarri D Kolusheva S Galletti P Tagliavini E Jelinek R 《Biochimica et biophysica acta》2012,1818(12):2967-2974
Ionic liquids (ILs) are a class of diverse organic salts with relatively low melting points (below 100°C) which have attracted considerable interest as a promising "green" substitute for organic solvents. The broad solvation properties of ILs and their high solubility in water, however, present health risks, in particular since it was shown that many ILs exhibit cytotoxic properties. In this context, interactions of ILs with the cellular membrane are believed to constitute a primary culprit for toxicity. We present a comprehensive biophysical and microscopy study of membrane interactions of a series of ILs having different side-chain compositions and lengths, and cationic head-group structures and orientations. The experimental data reveal that the ILs studied exhibit distinct mechanisms of membrane binding, insertion, and disruption which could be correlated with their biological activities. The results indicate, in particular, that both the side chain composition and particularly the head-groups of ILs constitute determinants for membrane activity and consequent cell toxicity. This work suggests that tuning membrane interactions of ILs should be an important factor for designing future compounds with benign environmental impact. 相似文献
107.
Jelena M. Aleksi? Danilo Stojanovi? Bojana Banovi? Radi?a Jan?i? 《Biochemical genetics》2012,50(11-12):881-892
We report an efficient, simple, and cost-effective protocol for the isolation of genomic DNA from an aromatic medicinal plant, common sage (Salvia officinalis L.). Our modification of the standard CTAB protocol includes two polyphenol adsorbents (PVP 10 and activated charcoal), high NaCl concentrations (4?M) for removing polysaccharides, and repeated Sevag treatment to remove proteins and other carbohydrate contaminants. The mean DNA yield obtained with our Protocol 2 was 330.6?μg DNA g?1 of dry leaf tissue, and the absorbance ratios 260/280 and 260/230?nm averaged 1.909 and 1.894, respectively, revealing lack of contamination. PCR amplifications of one nuclear (26S rDNA) and one chloroplast (rps16-trnK) locus indicated that our DNA isolation protocol may be used in common sage and other aromatic and medicinal plants containing essential oil for molecular biologic and biotechnological studies and for population genetics, phylogeographic, and conservation surveys in which nuclear or chloroplast genomes would be studied in large numbers of individuals. 相似文献
108.
Saraiva DG Fournier GF Martins TF Leal KP Vieira FN Câmara EM Costa CG Onofrio VC Barros-Battesti DM Guglielmone AA Labruna MB 《Experimental & applied acarology》2012,58(2):159-166
From June 2005 to November 2010, 43 small mammals encompassing 6 species of Didelphimorphia, 8 species of Rodentia, and 1 species of Lagomorpha were found parasitized by ticks in the state of Minas Gerais, southeastern Brazil. Nine tick species, in total 186 specimens, were identified as follows: Amblyomma cajennense (larvae and nymphs) on opossums and rodents; Amblyomma ovale (nymphs) on rodents; Amblyomma parvum (nymphs) on rodents; Amblyomma coelebs (nymphs) on opossums; Amblyomma dubitatum (nymph) on opossums; Ixodes amarali (females, nymphs, and larvae) on opossums and rodents; Ixodes loricatus (male, females, nymph) on opossums; Ixodes schulzei (female) on rodents; and Haemaphysalis leporispalustris (female) on rabbits. Most of the tick-host associations found in the present study have never been recorded in the literature; those include three new host records for I. amarali, four for A. cajennense, one for A. dubitatum, two for A. ovale, and one for A. coelebs. In addition, we provide the first record of A. coelebs in the state of Minas Gerais. 相似文献
109.
Paulo E. C. Peixoto Danilo Muniz Woodruff W. Benson 《Ethology : formerly Zeitschrift fur Tierpsychologie》2012,118(3):311-319
Among polygynous species, males often compete for the possession of mating sites to increase their reproductive success. Weaker individuals frequently adopt alternative non‐territorial mate‐locating tactics, but the adoption of alternative territorial tactics may also occur. Although alternative tactics with territory defence are less common in arthropods, factors that drive its adoption may provide information to understand the organization of different territorial mating systems in the group. Here we investigate the adoption of resource‐based territoriality as an alternative to a non‐resource‐based one by males of the butterfly Paryphthimoides phronius. Male P. phronius commonly defend sunny clearings lacking feeding resources in the forest edge (non‐resource‐based territoriality). However, after experimentally offering fermenting fruit in previously undefended sites, we showed that males also adopt a resource defence tactic. Males in territories with fermenting fruits apparently feed on this resource when they are not defending the territory. However, males in sites without resources did not migrate to territories with resources when given the opportunity. To our knowledge, this is the first experimental investigation to show a non‐resource‐ and an alternative resource‐based mate‐locating tactic in a butterfly. We suggest that this behavioural flexibility may represent an important step to understand the ecological factors responsible for the organization and evolution of different territorial mating systems in insects. 相似文献
110.
Ogrzewalska M Saraiva DG Moraes-Filho J Martins TF Costa FB Pinter A Labruna MB 《Parasitology》2012,139(10):1283-1300
SUMMARY The tick-borne bacterium Rickettsia rickettsii is the aetiological agent of Brazilian spotted fever (BSF). The present study evaluated tick infestations on wild and domestic animals, and the rickettsial infection in these animals and their ticks in 7 forest areas adjacent to human communities in the S?o Paulo Metropolitan Area (SPMA). The results were compared to ecological traits of each sampled area. Two main tick species, Amblyomma aureolatum and Rhipicephalus sanguineus, were collected from dogs. The major ticks found on small mammals and birds were Ixodes loricatus and Amblyomma longirostre, respectively. Both anti-R. rickettsii antibodies and R. rickettsii-infected ticks were detected on dogs from only 2 areas in the southern part of the SPMA, which were considered to be endemic for BSF; the remaining 5 areas were considered to be non-endemic. Ecologically, the BSF-endemic areas clearly differed from the non-endemic areas by the presence of significantly more degraded forest patches in the former. The present results corroborate historical observations that have indicated that all human cases of BSF in the SPMA were contracted in the southern part of this metropolitan area. However, not all forest patches in the southern part of the SPMA were shown to be associated with BSF endemism. 相似文献