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81.
A fragment of a putative L-type Ca(2+) channel has been identified by molecular biology experiments in immunocytes from the mussel Mytilus galloprovincialis. Using the cell permeable and Ca(2+)-specific fluorochrome FURA 2-AM, we have demonstrated that the algal toxin yessotoxin (YTX) is able to increase intracellular Ca(2+) concentration in M. galloprovincialis immunocytes. The YTX effect on Ca(2+) increase is inhibited by the L-type Ca(2+) channel inhibitor, verapamil, which is cAMP- and cGMP-dependent, but PKA- and nitric oxide-independent. On the basis of these observations, a possible role for YTX as a potential disturber of mussel immune efficiency is suggested. 相似文献
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Maioli G Pistone D Bonilauri P Pajoro M Barbieri I Mulatto P Patrizia M Vicari N Dottori M 《Experimental & applied acarology》2012,57(2):199-208
Ticks are the main vectors of rickettsiae of the spotted fever group, as well as of a variety of other Rickettsiales, including bacteria of the genus Anaplasma, that might cause diseases in humans and animals. Here we present the result of a survey for ticks and for tick-associated Rickettsiales in the Emilia Romagna region (Northern Italy). The study was focused on ticks collected from wild-hunted animals. Out of 392 ticks collected from these animals, 282 (72%) were identified as Ixodes ricinus, 110 (28%) as Dermacentor marginatus. The former was found on four vertebrate species, whereas the latter appeared more specific for wild boar. The presence of rickettsiae was demonstrated in 22.5% of I. ricinus (57/253) and in 29% of D. marginatus (32/110). Five ticks of the species I. ricinus were also positive for Anaplasma phagocytophilum (2%). In addition, we collected ticks by dragging in a natural park of the same region. All of the ticks captured by dragging were identified as I. ricinus. Thirty-six out of 200 analyzed ticks proved positive for Rickettsia monacensis and R. helvetica (16.5 and 1.5%, respectively). Our results highlight that that ticks present in wild areas, widely exploited for recreation and hunting in Emilia-Romagna, represent a risk for the transmission of spotted fevers and anaplasmosis to humans. 相似文献
84.
Zaharenko AJ Schiavon E Ferreira WA Lecchi M de Freitas JC Richardson M Wanke E 《Peptides》2012,34(1):158-167
During their evolution, animals have developed a set of cysteine-rich peptides capable of binding various extracellular sites of voltage-gated sodium channels (VGSC). Sea anemone toxins that target VGSCs delay their inactivation process, but little is known about their selectivities. Here we report the investigation of three native type 1 toxins (CGTX-II, δ-AITX-Bcg1a and δ-AITX-Bcg1b) purified from the venom of Bunodosoma cangicum. Both δ-AITX-Bcg1a and δ-AITX-Bcg1b toxins were fully sequenced. The three peptides were evaluated by patch-clamp technique among Nav1.1-1.7 isoforms expressed in mammalian cell lines, and their preferential targets are Na(v)1.5>1.6>1.1. We also evaluated the role of some supposedly critical residues in the toxins which would interact with the channels, and observed that some substitutions are not critical as expected. In addition, CGTX-II and δ-AITX-Bcg1a evoke different shifts in activation/inactivation Boltzmann curves in Nav1.1 and 1.6. Moreover, our results suggest that the interaction region between toxins and VGSCs is not restricted to the supposed site 3 (S3-S4 linker of domain IV), and this may be a consequence of distinct surface of contact of each peptide vs. targeted channel. Our data suggest that the contact surfaces of each peptide may be related to their surface charges, as CGTX-II is more positive than δ-AITX-Bcg1a and δ-AITX-Bcg1b. 相似文献
85.
Kopittke PM de Jonge MD Menzies NW Wang P Donner E McKenna BA Paterson D Howard DL Lombi E 《Plant physiology》2012,159(3):1149-1158
Arsenic (As) is considered to be the environmental contaminant of greatest concern due to its potential accumulation in the food chain and in humans. Using novel synchrotron-based x-ray fluorescence techniques (including sequential computed tomography), short-term solution culture studies were used to examine the spatial distribution of As in hydrated and fresh roots of cowpea (Vigna unguiculata 'Red Caloona') seedlings exposed to 4 or 20 μm arsenate [As(V)] or 4 or 20 μm arsenite. For plants exposed to As(V), the highest concentrations were observed internally at the root apex (meristem), with As also accumulating in the root border cells and at the endodermis. When exposed to arsenite, the endodermis was again a site of accumulation, although no As was observed in border cells. For As(V), subsequent transfer of seedlings to an As-free solution resulted in a decrease in tissue As concentrations, but growth did not improve. These data suggest that, under our experimental conditions, the accumulation of As causes permanent damage to the meristem. In addition, we suggest that root border cells possibly contribute to the plant's ability to tolerate excess As(V) by accumulating high levels of As and limiting its movement into the root. 相似文献
86.
Toffanello ED Perissinotto E Sergi G Zambon S Musacchio E Maggi S Coin A Sartori L Corti MC Baggio G Crepaldi G Manzato E 《PloS one》2012,7(4):e34950
Background
The role of Vitamin D in musculoskeletal functionality among elderly people is still controversial. We investigated the association between serum 25-hydroxyvitamin D (25OHD) levels and physical performance in older adults.Methods
2694 community-dwelling elderly women and men from the Progetto Veneto Anziani (Pro.V.A.) were included. Physical performances were assessed by: tandem test, 5 timed chair stands (TCS), gait speed, 6-minute walking (6 mW) distance, handgrip strength, and quadriceps strength. For each test, separate general linear models and loess plots were obtained in both genders, in relation to serum 25OHD concentrations, controlling for several potential confounders.Results
Linear associations with 25OHD levels were observed for TCS, gait speed, 6 mW test and handgrip strength, but not for tandem test and quadriceps strength. After adjusting for potential confounders, linear associations with 25OHD levels were still evident for the 6 mW distance in both genders (p = .0002 in women; <.0001 in men), for TCS in women (p = .004) and for gait speed (p = .0006) and handgrip strength (p = .03) in men. In loess analyses, performance in TCS in women, in gait speed and handgrip strength in men and in 6 mW in both genders, improved with increasing levels of 25OHD, with most of the improvements occurring for 25OHD levels from 20 to 100 nmol/L.Conclusion
lower 25OHD levels are associated with a worse coordination and weaker strength (TCS) in women, a slower walking time and a lower upper limb strength in men, and a weaker aerobic capacity (6 mW) in both genders. For optimal physical performances, 25OHD concentrations of 100 nmol/L appear to be more advantageous in elderly men and women, and Vitamin D supplementation should be encouraged to maintain their 25OHD levels as high as this threshold. 相似文献87.
E Ricciardi M Jakimovska P Maniglio M Schimberni A Frega B Kobal M Moscarini 《World journal of surgical oncology》2012,10(1):177
ABSTRACT: BACKGROUND: Intraoperative injury of the obturator nerve has rarely been reported in patients with gynecological malignancies undergoing extensive radical surgeries. Irreversible damage of this nerve causes thigh paresthesia and claudication. Intraoperative repair may be done by end-to-end anastomosis or grafting when achieving tension-free anastomosis is not possible. CASE PRESENTATION: A 28-year-old woman with stage IB cervical cancer underwent fertility--sparing surgery, including conization and bilateral pelvic lymphadenectomy. The left obturator nerve was damaged intraoperatively during pelvic dissection. CONCLUSION: Immediate laparoscopic repair was successful and there was no functional deficit in the left thigh for six months postoperatively. 相似文献
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Annaratone L Marchiò C Renzulli T Castellano I Cantarella D Isella C Macrì L Mariscotti G Balmativola D Cantanna E Deambrogio C Pietribiasi F Arisio R Schmitt F Medico E Sapino A 《Translational oncology》2012,5(3):180-189
We investigated whether residual material from diagnostic smears of fine needle aspirations (FNAs) of mammographically detected breast lesions can be successfully used to extract RNA for reliable gene expression analysis. Twenty-eight patients underwent FNA of breast lesions under ultrasonographic guidance. After smearing slides for cytology, residual cells were rinsed with TRIzol to recover RNA. RNA yield ranged from 0.78 to 88.40 μg per sample. FNA leftovers from 23 nonpalpable breast cancers were selected for gene expression profiling using oligonucleotide microarrays. Clusters generated by global expression profiles partitioned samples in well-distinguished subgroups that overlapped with clusters obtained using "biologic scores" (cytohistologic variables) and differed from clusters based on "technical scores" (RNA/complementary RNA/microarray quality). Microarray profiling used to measure the grade of differentiation and estrogen receptor and ERBB2/HER2 status reflected the results obtained by histology and immunohistochemistry. Given that proliferative status in the FNA material is not always assessable, we designed and performed on FNA leftover a multiprobe genomic signature for proliferation genes that strongly correlated with the Ki67 index examined on histologic material. These findings show that cells residual to cytologic smears of FNA are suitable for obtaining high-quality RNA for high-throughput analysis even when taken from small nonpalpable breast lesions. 相似文献
90.