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Natural vegetation cover in the landscape and edge effects： differential responses of insect orders in a fragmented forest

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Insect Science 2017年第5期24卷 891-901页

作者： Ezequiel Gonzalez Adriana Salvo graciela Valladares Centro de Investigaciones Entomologicas de Cordoba IMBIV UNC CONICET FCEFyN Av. Velez Sarfield 1611 Cordoba CordobaX5000GMC Argentina

Human activities have led to global simplification of ecosystems, among which Neotropical dry forests are some of the most threatened. Habitat loss as well as edge effects may affect insect communities. Here, we analyzed insects sampled with pan traps in 9 landscapes （at 5 scales, in 100-500 m diameter circles） comprising cultivated fields and Chaco Serrano forests, at overall community and taxonomic order level. In total 7043 specimens and 456 species of hexapods were captured, with abundance and richness being directly related to forest cover at 500 m and higher at edges in comparison with forest interior. Community composition also varied with forest cover and edge^interior location. Different responses were detected among the 8 dominant orders. Collembola, Hemiptera, and Orthoptera richness and^or abundance were positively related to forest cover at the larger scale, while Thysanoptera abundance increased with forest cover only at the edge. Hymenoptera abundance and richness were negatively related to forest cover at 100 m. Coleoptera, Diptera, and Hymenoptera were more diverse and abundant at the forest edge. The generally negative influence of forest loss on insect communities could have functional consequences for both natural and cultivated systems, and highlights the relevance of forest conservation. Higher diversity at the edges could result from the simultaneous presence of forest and matrix species, although ＂resource mapping＂ might be involved for orders that were richer and more abundant at edges. Adjacent crops could benefit from forest proximity since natural enemies and pollinators are well represented in the orders showing nositive edge effects.

关键词： Chaco Serrano edge effect forest cover habitat loss insects orders

Arthropods on plants in a fragmented Neotropical dry forest： A functional analysis of area loss and edge effects

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Insect Science 2015年第1期22卷 129-138页

作者： Ezequiel Gonzalez Adriana Salvo graciela Valladares Centro de Investigaciones Entomol6gicas de C6rdoba (IMBIV - CONICET) and Universidad Nacional de C6rdoba C6rdoba Argentina

Loss and fragmentation of natural ecosystems are widely recognized as the most important threats to biodiversity conservation, with Neotropical dry forests among the most endangered ecosystems. Area and edge effects are major factors in fragmented landscapes. Here, we examine area and edge effects and their interaction, on ensembles of arthropods associated to native vegetation in a fragmented Chaco Serrano forest. We analyzed family richness and community composition of herbivores, predators, and parasitoids on three native plant species in 12 fragments of varying size and at edge/interior positions. We also looked for indicator families by using Indicator Species Analysis. Loss of family richness with the reduction of forest fragment area was observed for the three functional groups, with sirnilar magnitude. Herbivores were richer at the edges without interaction between edge and area effects, whereas predators were not affected by edge/interior position and parasitoid richness showed an interaction between area and position, with a steeper area slope at the edges. Family composition of herbivore, predator, and parasitoid assemblages was also affected by forest area and/or edge/interior situation. We found three indicator families for large remnants and five for edges. Our results support the key role of forest area for conservation of arthropods taxonomic and functional diversity in a highly threatened region, and emphasize the need to understand the interactions between area and edge effects on such diversity.

关键词： area loss Chaco Serrano edge effect forest arthropods functional groups habitat fragmentation

Endophytes versus biotrophic and necrotrophic pathogens—are fungal lifestyles evolutionarily stable traits?

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Fungal Diversity 2013年第3期60卷 125-135页

作者： Luis Delaye graciela García-Guzmán Martin Heil Departamento de Ingeniería Genética Centro de Investigación y de Estudios Avanzados(CINVESTAV)IrapuatoGuanajuatoMexico Departamento de Ecología Evolutiva Instituto de EcologíaUNAMMéxico CityMexico

Endophytes infect living plant tissues without causing symptoms of ***,many of them contribute to the resistance phenotype of their ***,fungal endophytes are generally closely related to plant pathogens,fungi that either develop within living host tissue(biotrophic fungi)or that kill the host cells and then live in the dead tissue(necrotrophic fungi).We adopted a phylogenetic approach to investigate whether these strategies represent evolutionarily stable lifestyles and to elucidate their general phylogenetic *** analysed 163 fungal strains for which we found information on the sequence of the 5.8S rRNA gene and the flanking internal transcribed spacer regions,the identity of the host plant and the concrete phenotypic outcome of the infection.A Maximum-Likelihood analysis combined with ancestral character mapping by maximum parsimony revealed that some fungal lineages had switched multiple times between a necrotrophic and an endophytic *** character mapping indicated a minimum of four changes from an endophytic to a necrotrophic lifestyle,four changes in the opposite direction and eight changes among these lifestyles for which the direction could not be determined *** contrast,biotrophs formed five clusters that did not contain necrotrophs or *** biotrophy evolves there is apparently no regression to one of the other two *** conclude that biotrophy usually represents a derived and evolutionarily stable trait,whereas fungi easily can switch between an endophytic and necrotrophic lifestyle at the evolutionary and even the ecological *** experimental studies should focus on the environmental or genetic changes that cause the rapid switches between these two phenotypically different lifestyles.

关键词： Disease expression Fungi Plant pathogens Phylogenetic effects

Mapping data gaps to estimate biomass across Brazilian Amazon forests

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Forest Ecosystems 2020年第3期7卷 334-348页

作者： graciela Tejada Eric Bastos Görgens Alex Ovando Jean Pierre Ometto Earth System Science Center(CCST) National Institute for Space Research(INPE)Av dos Astronautas 1758São Josédos CamposSP12227-010Brazil Department of Forestry Engineering Universidade Federal dos Vales do Jequitinhonha e MucuriCampus JKRod.MGT 367km 5835000Alto do JacubaDiamantinaMG39100-000Brazil National Center for Monitoring and Early Warning of Natural Disasters(CEMADEN) Estrada Doutor Alino Bondesani 500São Josédos CamposSP12247-016Brazil

Background: Tropical forests play a fundamental role in the provision of diverse ecosystem services, such as biodiversity,climate and air quality regulation, freshwater provision, carbon cycling, agricultural support and culture. To understand the role of forests in the carbon balance, aboveground biomass(AGB) estimates are needed. Given the importance of Brazilian tropical forests, there is an urgent need to improve AGB estimates to support the Brazilian commitments under the United Nations Framework Convention on Climate Change(UNFCCC). Many AGB maps and datasets exist, varying in availability, scale and coverage. Thus, stakeholders, policy makers and scientists must decide which AGB product, dataset or combination of data to use for their particular goals. In this study, we assessed the gaps in the spatial AGB data across the Brazilian Amazon forests not only to orient the decision makers about the data that are currently available but also to provide a guide for future ***: We obtained a map of the gaps in the forest AGB spatial data for the Brazilian Amazon using statistics and differences between AGB maps and a spatial multicriteria evaluation that considered the current AGB datasets. The AGB spatial data gap map represents areas with good coverage of AGB data and, consequently, the main gaps or priority areas where further biomass assessments should focus, including the northeast of Amazon State, Amapá and northeast of Pará. Additional y, by quantifying the variability in both the AGB maps and field data on multiple environmental factors,we provide valuable elements for understanding the current AGB data as a function of climate, soil, vegetation and ***: The map of AGB data gaps could become a useful tool for policy makers and different stakeholders working on National Communications, Reducing Emissions from Deforestation and Degradation(REDD+), or carbon emissions modeling to prioritize places to implement further AGB a

关键词： Amazon Tropical forest Carbon Aboveground biomass Data gaps REDD+ Environmental factors

Therapeutic effect of Streptococcus thermophilus CRL 1190-fermented milk on chronic gastritis

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World Journal of Gastroenterology 2010年第13期16卷 1622-1630页

作者： Cecilia Rodríguez Marta Medici Fernanda Mozzi graciela Font de Valdez Centro de Referencia para Lactobacilos (CERELA)-CONICET Cátedra Microbiología Superior Facultad de Bioquímica Química y Farmacia Universidad Nacional de Tucumán

AIM: To investigate the potential therapeutic effect of exopolysaccharide (EPS)-producing Streptococcus thermophilus (S. thermophilus) CRL 1190 fermented milk on chronic gastritis in Balb/c mice. METHODS: Balb/c mice were fed with the fermented milk for 7 d after inducing gastritis with acetyl-salicylic acid (ASA, 400 mg/kg body weight per day for 10 d). Omeprazole was included in this study as a positive therapeutic control. The gastric in? ammatory activity was evaluated from gastric histology and in? ammation score, number of interleukin-10 (IL-10), interferon-γ (INFγ) and tumor necrosis factor-α (TNF-α) cytokine-producing cells in the gastric mucosa, and thickness of the mucus layer. RESULTS: Animals receiving treatment with the EPS-producing S. thermophilus CRL 1190 fermented milk showed a conserved gastric mucosa structure similar to that of healthy animals. In? ammation scores of the fermented milk-treated mice were lower than those of mice in the gastritis group (0.2 ± 0.03 vs 2.0 ± 0.6, P < 0.05). A marked decrease in INFγ+ (15 ± 1.0 vs 28 ± 1.2, P < 0.05) and TNF-α+ (16 ± 3.0 vs 33 ± 3.0, P < 0.05) cells and an increase in IL-10+ (28 ± 1.5 vs 14 ± 1.3, P < 0.05) cells compared to the gastritis group, was observed. Also, an increase in the thickness of the mucus gel layer (2.2 ± 0.6 vs 1.0 ± 0.3; 5.1 ± 0.8 vs 1.5 ± 0.4 in the corpus and antrum mucosa, respectively, P < 0.05) compared with the gastritis group was noted. A milk suspension of the purif ied EPS from S. thermophilus CRL1190 was also effective as therapy for gastritis.

关键词： Lactic acid bacteria Probiotics Gastritis Streptococcus thermophilus Exopolysaccharides

Modulation of IL-10/IL-10R expression by mafosfamide, a derivative of 4-hydroxycyclophosphamide, in a rat B-cell lymphoma

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BIOCELL 2012年第2期36卷 91-95页

作者： MARÍA J.RICO PABLO MATAR O.graciela SCHAROVSKY Instituto de Genética Experimental Facultad de Ciencias MédicasUniversidad Nacional de RosarioSanta Fe 3100(2000)RosarioArgentina Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET). Consejo de Investigaciones UNRRosarioArgentina

We have already shown that IL-10 plays an important role in immunosuppression and metastatic dissemination in the rat B-cell lymphoma L-TACB *** was suggested that the up-regulation of IL10 production and IL-10 receptor(IL-10R)expression would be part of the transition from primary tumor to metastatic phenotype and that IL-10,besides its immunosuppressive activity,may act as a growth factor for metastatic L-TACB *** treatment of L-TACB-bearing rats with a single low-dose cyclophosphamide decreased IL-10 production,reverted immunosuppression and induced the immunologic rejection of tumor metastasis without any effect on primary tumor *** current aim was to investigate the effects of cyclophosphamide on the expression of IL-10 and IL-10R on primary and metastatic L-TACB *** that cyclophosphamide is a prodrug,we used mafosfamide,a compound that yields in vitro the same active metabolites as cyclophosphamide does in *** induced down-regulation of IL-10 production and IL-10R expression on metastatic cells and,concomitantly,inhibited metastatic cell *** suggest that mafosfamide would inhibit the regulatory loop mediated by the IL-10/IL-10R system and,as a consequence,metastatic cell *** results may have a considerable impact on the design of new therapies for metastatic lymphomas.

关键词： metastasis cyclophosphamide cell proliferation

Chemical and spectroscopic characterization of humic substances from sediment and riparian soil of a highly polluted urban river(Suquía River,Córdoba,Argentina)

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International Journal of Sediment Research 2020年第3期35卷 287-294页

作者： Carolina Merlo Carolina Vázquez Ana graciela Iriarte Carlos Matías Romero Instituto Multidisciplinario de Biologia Vegetal (CONICET) Facultad de Ciencias Agropecuarias Universidad Nacional de Cordoba INFIQC Departament of FisicoquimicaFacultad de Ciencias QuimicasUniversidad Nacional de Cordoba Agriculture and Agri-Food Canada Lethbridge Research and Development Centre Department of Biological Sciences University of Lethbridge

The Suquia River,the largest urban river in Cordoba(Argentina),has been severely polluted for *** must be taken to restore its environmental quality by managing riparian zones for increased water-self *** current study aimed to characterize organic matter(OM) dynamics and humic substances(HS) spectrochemical properties along the lower-middle basin of the Suquia *** soil(0-20 cm) and sediment(0-10 cm) samples were collected from a reference location(S1)and four polluted sites(S2-S5) during a low-flow *** contents of soil and sedimentary OM and HS fractions were analyzed by wet oxidation,as well as HS Fourier transform infrared(FT-IR) and ultraviolet-visible(UV-Vis) spectrochemical *** OM and HS fractions from riparian soil were high upstream of Cordoba City(S1 and S2,50.2-50.4 g/kg OM) and within a 50 km downstream location(S5,30.9 g/kg OM) owing to a surplus of fresh plant biomass-carbon(C) *** heterogeneous sediment samples did not show any significant differences among sites(P> 0.05).The lowest values of the ratio of absorbances at 465 and 665 nm(E4/E6)(1.78) and the Δ log K(0.15) coefficient(a measure of HS maturity degree) were obtained downstream of Cordoba City,for both riparian soil and sediment,indicating that HS were enriched by more condensed aromatic structures within highly degraded portions of the *** samples exhibited similar IR spectra,implying overlapping recalcitrant-C structures at the functional group level,but with different absorbance *** from the current study constitute a baseline for understanding the chemical nature of HS from sediment and riparian soil along the Suquia River and can be used as a reference for future studies tracking OM compositional changes over time.

关键词： Lotic ecosystems Organic matter Humic acids FT-IR spectroscopy UV-Vis spectroscopy

Induction of apoptosis on human hepatocarcinoma cell lines by an alkyl resorcinol isolated from Lithraea molleoides

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World Journal of Gastroenterology 2006年第37期12卷 5959-5963页

作者： Luciana Barbini Paula Lopez Julieta Ruffa Virginia Martino graciela Ferraro Rodolfo Campos Lucia Cavallaro Catedra de Virologia Facultad de Farmacia y Bioquimica Universidad de Buenos Aires. Junin 956 (1113) Buenos Aires Argentina Catedra de Farmacognosia Facultad de Farmacia y Bioquimica Universidad de Buenos Aires. Junin 956 (1113) Buenos Aires Argentina

AIM: To study the mechanism of cytotoxicity of a new active 5-alkyl resorcinol [1, 3-dihydroxy-5- (tridec-4’, 7’ -dienyl) benzene] isolated from Lithraea molleoides leaves on liver tumor cells. METHODS: Human hepatocarcinoma cell lines (HepG2 and Hep3B) in culture were treated with inhibitory concentrations, 50% of the compound, for 24 h. The induction of apoptosis was detected in treated cells by analysis of DNA fragmentation, DNA content, and acridine orange and propidium iodide staining. RESULTS: After 24 h of 5-alkyl resorcinol treatment, both cell lines showed: (1) the typical morphological alterations of apoptosis; (2) DNA fragmentation, detected by laddering and appearance of a subG0 population by flow cytometry; and (3) condensed and fragmented nuclei by acridine orange-propidium iodide staining. CONCLUSION: Based on the results, this compound exerts its cytotoxic effect in both hepatocellular cell lines through apoptotic cell death. For Hep3B, cells with mutated p53 and Fas, apoptosis would proceed by p53- or Fas-independent pathways.

关键词： Lithraea molleoides Cytotoxic activity Alkyl resorcinol Apoptosis Hepatoma

Prostate cancer upgrading or downgrading of biopsy Gleason scores at radical prostatectomy:prediction of"regression to the mean"using routine clinical features with correlating biochemical relapse rates

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Asian Journal of Andrology 2019年第6期21卷 598-604页

作者： Muammer Altok Patricia Troncoso Mary F Achim Surena F Matin graciela N Gonzalez John W Davis Department of Urology University of Texas MD Anderson Cancer CenterHoustonTX 77030USA Department of Pathology University of Texas MD Anderson Cancer CenterHoustonTX 77030USA Department of Biostatistics University of Texas MD Anderson Cancer CenterHoustonTX 77030USA.

Recommendations for managing clinically localized prostate cancer are structured around clinical risk criteria,with prostate biopsy(PB)Gleason score(GS)being the most important *** to radical prostatectomy(RP)specimen upgrading/downgrading is welldescribed,and is often the ratio nale for costly imaging or genomic *** prese nt simple,no-cost an a lyses of clinical parametersto predict which GS 6 and GS 8 patients will change to GS 7 at *** May 2006 to December 2012,1590 patientsunderwent robot-assisted radical prostatectomy(RARP).After exclusions,we identified a GS 6 cohort of 374 patients and a GS 8cohort of 91 *** this era,>1000 additional patients were enrolled in an active surveillanee(AS)*** GS 6,265(70.9%)of 374 patients were upgraded,and the cohort included 183(48.9%)patients eligible for AS by the Prostate Cancer ResearchInternational Active Surveillance Study(PRIAS)standards,of which 57.9%were *** features that predicted a>90%chanceof upgrading included≥7 cores positive,maximum foci length≥8 mm in any core,and total tumor involvement≥30%.For GS 8,downgrading occurred in 46(50.5%),which was significantly higher for single core versus multiple cores(80.4%vs 19.6%,P=0.011).Biochemical recurre nee(BCR)occurred in 3.4%of GS 6 upgraded versus 0%non upgraded,and in GS 8,19.6%downgraded versus42.2%nondown *** coun seling men with clin ically localized prostate can cer,the odds of GS cha nge should be presented,andcertain men with high-volume GS 6 or low-volume GS 8 can be counseled with GS 7-based recommendations.

关键词： biopsy down grade Gleas on score prostate cancer upgrade