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91.
M. G. Giacobbe A. Penna E. Gangemi M. Masò E. Garcés S. Fraga I. Bravo F. Azzaro N. Penna 《Hydrobiologia》2007,580(1):125-133
Summer outbreaks of the dinoflagellate Alexandrium taylorii Balech are recurrent events in nearshore waters of Sicily (Italy)—a central region in the Mediterranean Sea—producing dense
yellowish–green patches. Beyond the local phenomenon, the problem covers a broader geographic scale, involving also other
European localities, mostly in Spain.
Biological, environmental, and molecular data are reported here from a semi-closed bay of Sicily (Vulcano Island, Tyrrhenian
Sea, 2000–2003), showing in summer the recurrence of high-biomass blooms and events of water discolouration. Without underestimating
the setbacks to the tourism industry, the ecological impact of A. taylorii blooms may be important considering the high levels of biomass produced (West Bay, Vulcano: up to a magnitude order of 107 cells l−1, 50–180 μg-Chla l−1, June 2002 and 2003) and coincident conditions of oxygen supersaturation of the waters (130–170%). Trophic trends in the
Tyrrhenian site indicate high amounts of nutrients linked to the increased anthropogenic activity in summer, although recently
there has been an apparent shift of the marked eutrophic conditions towards a slighter eutrophy.
Genetic data on isolates of A. taylorii from the Mediterranean Sea are also discussed. Molecular analyses implied the sequencing of target rDNA regions (5.8S rDNA
and ITS regions) of several isolates from different Mediterranean localities, as well as the application of species-specific
PCR assays for rapid species identification in preserved field samples. The confirmation of the specific identity provided
new insights into the biogeography of this species and further evidence of the occurrence of A. taylorii in a number of Mediterranean localities, both in the western side (the Catalan coast of Spain) and the eastern area (Greece).
Analyses of the molecular diversity of geographically distinct isolates of A. taylorii from Italy, Spain, and Greece based on the 5.8S rDNA-ITS region sequences showed a high level of similarity, indicating the
existence of an unique Mediterranean population. 相似文献
92.
Furlan S La Penna G Guerrieri F Morante S Rossi GC 《European biophysics journal : EBJ》2007,36(7):841-845
First principle ab initio molecular dynamics simulations of the Car-Parrinello type have proved to be of invaluable help in understanding the microscopic mechanisms of chemical bonding both in solid state physics and in structural biophysics. In this work we present as a test case a study of the Cu coordination mode at the Prion Protein binding sites localized in the N-terminal octarepeat region. Using medium size PC-clusters, we are able to deal with systems with up to about 350 atoms and 10(3) electrons for as long as approximately 2 ps. With a foreseeable forthcoming scaling up of the available CPU times by a factor 10(3), one can hope to be soon able to simulate systems of biological interest of realistic size and for physical times of the order of the nanosecond. 相似文献
93.
Aimbire F Penna SC Rodrigues M Rodrigues KC Lopes-Martins RA Sertié JA 《Prostaglandins, leukotrienes, and essential fatty acids》2007,77(3-4):129-138
Ginger, the rhizome of Zingiber officinalis Roscoe (Zingiberaceae), is a common constituent of diets around the world and its extracts have been reported to exhibit several pharmacological activities. We investigated the effect of crude hydroalcoholic extract of ginger on the rat trachea hyperreactivity (RTHR) and lung inflammation induced by lipopolysaccharide (LPS). Our results demonstrate that ginger extract and celecoxib attenuated RTHR 90 min and 48 h after LPS. Ginger and celecoxib reduced the serum level of prostaglandin (PGE2) and thromboxane (TXA2) 90 min after LPS. Celecoxib and ginger also reduced myeloperoxidase activity and the number of cells in rat bronchoalveolar lavage 48 h post-LPS. On lung parenchyma, ginger and celecoxib reduced the release of PGE2 and TXA2 48 h post-LPS. These results suggest that ginger exerts an anti-inflammatory effect on lung attenuating RTHR and COX metabolites seem to be involved in these processes. 相似文献
94.
Adorini L Penna G Amuchastegui S Cossetti C Aquilano F Mariani R Fibbi B Morelli A Uskokovic M Colli E Maggi M 《The Journal of steroid biochemistry and molecular biology》2007,103(3-5):689-693
The prostate is a target organ of vitamin D receptor (VDR) agonists and represents an extra-renal site of 1,25-dihydroxyvitamin D3 synthesis, but its capacity to respond to VDR agonists has, so far, been almost exclusively probed for the treatment of prostate cancer. We have analyzed the capacity of VDR agonists to treat benign prostatic hyperplasia (BPH), a complex syndrome characterized by a static component related to prostate overgrowth, a dynamic one responsible for urinary irritative symptoms, and an inflammatory component. Preclinical data demonstrate that VDR agonists, and notably BXL-628 (elocalcitol), reduce the static component of BPH by inhibiting the activity of intra-prostatic growth factors downstream of the androgen receptor, and the dynamic component by targeting bladder cells. In addition, BXL-628 inhibits production of proinflammatory cytokines and chemokines by human BPH cells. These data have led to a proof-of-concept clinical study that has successfully shown arrest of prostate growth in BPH patients treated with BXL-628, with excellent safety. We have documented the anti-inflammatory effects of BXL-628 also in animal models of autoimmune prostatitis, observing a significant reduction of intra-prostatic cell infiltrate following administration of this VDR agonist, at normocalcemic doses, in mice with already established disease. These data extend the potential use of VDR agonists to novel indications that represent important unmet medical needs, and provide a sound rationale for further clinical testing. 相似文献
95.
Histonelike proteins in prokaryotes and histone octamers in eukaryotes carry large positive charges, which are responsible of strong electrostatic interactions with DNA. As a result, DNA wraps around proteins and genetic information is condensed. We describe a generalized model of these electrostatic interactions mediated by salt that explains the wrapping of DNA around the nucleosome octamer, around remodeling factors in eukaryotes and around histonelike proteins in prokaryotes. It comes out that small changes in protein dimension and charge produce large effects in the supramolecular DNA-protein architecture. 相似文献
96.
Poonam Kanwar Sibaji K. Sanyal Swati Mahiwal Barkha Ravi Kanwaljeet Kaur Joel L. Fernandes Akhilesh K. Yadav Indu Tokas Ashish K. Srivastava Penna Suprasanna Girdhar K. Pandey 《The Plant journal : for cell and molecular biology》2022,109(1):241-260
Calcium (Ca2+) is widely recognized as a key second messenger in mediating various plant adaptive responses. Here we show that calcineurin B-like interacting protein kinase CIPK9 along with its interacting partner VDAC3 identified in the present study are involved in mediating plant responses to methyl viologen (MV). CIPK9 physically interacts with and phosphorylates VDAC3. Co-localization, co-immunoprecipitation, and fluorescence resonance energy transfer experiments proved their physical interaction in planta. Both cipk9 and vdac3 mutants exhibited a tolerant phenotype against MV-induced oxidative stress, which coincided with the lower-level accumulation of reactive oxygen species in their roots. In addition, the analysis of cipk9vdac3 double mutant and VDAC3 overexpressing plants revealed that CIPK9 and VDAC3 were involved in the same pathway for inducing MV-dependent oxidative stress. The response to MV was suppressed by the addition of lanthanum chloride, a non-specific Ca2+ channel blocker indicating the role of Ca2+ in this pathway. Our study suggest that CIPK9-VDAC3 module may act as a key component in mediating oxidative stress responses in Arabidopsis. 相似文献
97.
98.
Joilda Silva Nery Susan Martins Pereira Davide Rasella Maria Lúcia Fernandes Penna Rosana Aquino Laura Cunha Rodrigues Mauricio Lima Barreto Gerson Oliveira Penna 《PLoS neglected tropical diseases》2014,8(11)
Background
Social determinants can affect the transmission of leprosy and its progression to disease. Not much is known about the effectiveness of welfare and primary health care policies on the reduction of leprosy occurrence. The aim of this study is to evaluate the impact of the Brazilian cash transfer (Bolsa Família Program-BFP) and primary health care (Family Health Program-FHP) programs on new case detection rate of leprosy.Methodology/Principal Findings
We conducted the study with a mixed ecological design, a combination of an ecological multiple-group and time-trend design in the period 2004–2011 with the Brazilian municipalities as unit of analysis. The main independent variables were the BFP and FHP coverage at the municipal level and the outcome was new case detection rate of leprosy. Leprosy new cases, BFP and FHP coverage, population and other relevant socio-demographic covariates were obtained from national databases. We used fixed-effects negative binomial models for panel data adjusted for relevant socio-demographic covariates. A total of 1,358 municipalities were included in the analysis. In the studied period, while the municipal coverage of BFP and FHP increased, the new case detection rate of leprosy decreased. Leprosy new case detection rate was significantly reduced in municipalities with consolidated BFP coverage (Risk Ratio 0.79; 95% CI = 0.74–0.83) and significantly increased in municipalities with FHP coverage in the medium (72–95%) (Risk Ratio 1.05; 95% CI = 1.02–1.09) and higher coverage tertiles (>95%) (Risk Ratio 1.12; 95% CI = 1.08–1.17).Conclusions
At the same time the Family Health Program had been effective in increasing the new case detection rate of leprosy in Brazil, the Bolsa Família Program was associated with a reduction of the new case detection rate of leprosy that we propose reflects a reduction in leprosy incidence. 相似文献99.
100.
In the present study, the effect of arsenate (AsV) exposure either alone or in combination with calcium (Ca) was investigated in callus cultures of Brassica juncea (L.) Czern. cv. Pusa Bold grown for a period up to 24 h. The AsV?(250 μM) + Ca (10 mM) treatment resulted in a significantly higher level of As (464 μg g?1 dry weight (DW)) than AsV without Ca (167 μg g?1 DW) treatment at 24 h. Furthermore, AsV + Ca-treated calli had a higher percent of AsIII (24–47%) than calli subjected to AsV treatment (12–14%). Despite this, AsV + Ca-treated calli did not show any signs of hydrogen peroxide (H2O2) accumulation or cell death upon in vivo staining, while AsV-exposed calli had increased H2O2, shrinkage of cytoplasmic contents, and cell death. Thus, AsV treatment induced oxidative stress, which in turn elicited a response of antioxidant enzymes and metabolites as compared with control and AsV + Ca treatment. The positive effects of Ca supplementation were also correlated to an increase in thiolic constituents', viz., cysteine, reduced glutathione, and glutathione reductase in AsV + Ca than in AsV treatment. An analysis of selected signaling related genes, e.g., mitogen-activated protein kinases (MAPK3 and MAPK6) and jasmonate ZIM-domain (JAZ3) suggested that AsV and AsV + Ca followed variable pathways to sense and signal the As stress. In AsV-alone treatment, jasmonate signaling was seemingly activated, while MAPK3 was not involved. In contrast, AsV + Ca treatment appeared to specifically inhibit jasmonate signaling and activate MAPK3. In conclusion, Ca supplementation may hold promise for achieving increased As accumulation in plants without compromising their tolerance. 相似文献