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1.
FERNANDO DINI PAOLO BRACCHI ALESSANDRO GIANNÍ 《The Journal of eukaryotic microbiology》1987,34(2):236-243
A mating-type analysis was performed on 78 stocks of the marine hypotrich ciliate, Aspidisca sp., from a sufficient number of diverse geographic locations, some widely separated. Evidence is provided for the existence of a binary mating system in this "morphospecies." The collected stocks have been challenged by the most rigorous criterion, namely breeding affinity in the laboratory, and have yielded at least four reproductively, not necessarily geographically, isolated groups that are in fact "biological species," here referred to as "syngens." Different syngens contain different pairs of mating types. Syngens are morphologically indistinguishable; hence Aspidisca sp. can be considered a conservative taxon comprising a number of "cryptic" or "sibling species." Information is also presented about the mating behavior and the pattern of nuclear events at conjugation in Aspidisca sp. Search for soluble pheromones of the mating types gave only negative results. Hence, direct contact with potential partners is postulated to play a critical role in preparing individuals to mate. Mating reaction and mating which actually involves cross-fertilization (conjugation, sensu stricto) are completely inhibited by 10 μg/ml cycloheximide, suggesting the necessity of protein synthesis for recognition and union in conjugation of potential partners. 相似文献
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ILARIA ZOLLINO DIANA CAMPIONI MARIA GRAZIA SIBILLA MIRKO TESSARI ANNA MARIA MALAGONI PAOLO ZAMBONI 《Cytotherapy》2019,21(2):200-211
Background aims
Preclinical and observational reports indicate that adipose tissue (AT) is a safe and promising tool to treat non-healing venous leg ulcers (VLUs).Methods
From an initial cohort of 38 patients, 16 patients affected by non-healing VLUs were randomly allocated to the experimental arm (5 men and 3 women) and control arm (5 men and 3 women). In the experimental arm, wounds were treated by debridement, centrifuged adipose tissue (CAT), advanced dressings and compression. No experimental treatment (CAT) was administered to the control arm. We investigated the functional and the immunophenotypical features of the harvested CAT-derived stem cells. The primary outcome measures were healing time and safety of the cell treatment. Secondary outcomes were pain evaluated by numeric rating scale (NRS), complete wound healing at 24 weeks by Margolis Index and wound-healing process expressed in square centimeters per week. The various immunophenotypic and functional characteristics of CAT-derived stem cells were then correlated with the clinical outcomes.Results
No major adverse events were recorded. The healing time was significantly faster by applying CAT, 17.5 ± 7.0 weeks versus 24.5 ± 4.9 weeks recorded in the control arm (P < 0.036). NRS dropped after the first week to 2.7 ± 2.0 in the experimental arm versus 6.6 ± 3.0 in the control group (P < 0.01). The rate of healing at the 24th week was not significantly different between arms. Interestingly, we found a strong reverse correlation between the percent of CD34+/CD45– non-hematopoietic cells, respectively, with the healing time (r?=?–0.894, P < 0.041) and NRS (r?=?–0.934, P < 0.020).Conclusions
CAT is safe and may accelerate healing time in VLUs as well as reduce wound pain. The percentage of CD34+/CD45– cells in stromal vascular fraction (SVF) seems to be a predictive biomarker of successful CAT treatment in these patients. 相似文献3.
GIOVANNA BATTIPAGLIA PAOLO CHERUBINI† MATTHIAS SAURER‡ ROLF T. W. SIEGWOLF‡ SANDRO STRUMIA M. FRANCESCA COTRUFO 《Global Change Biology》2007,13(6):1122-1137
Volcanic eruptions impact the global and the hemispheric climate, but it is still unknown how and to what degree they force the climate system and in particular the global carbon cycle. In this paper, the relationships between individual eruptions (reconstructed for the past using written records), tree primary productivity (estimated using ring widths), photosynthetic rate and stomatal conductance (assessed by carbon and oxygen isotope data) are investigated, to understand the impact of volcanic eruptions on net primary production. Data from a mixed stand of Fagus sylvatica L. and Acer pseudoplatanus L. located in the area of the Vesuvio volcanic complex (Southern Italy) showed a significant decrease in ring width following each eruption. Isotope analyses indicate a change in climatic conditions after such events. Specifically, the lower oxygen isotope ratio in the tree‐ring cellulose strongly suggests an increase in relative humidity and a decrease in temperature, with the latter resulting in a strong limitation to tree‐ring growth. The carbon isotope ratio was only moderately but not significantly reduced in the years of volcanic eruption, suggesting no major changes in C fixation rates. This work is a case study on the effects of volcanic eruptions resulting in strong climatic changes on the local scale. This is an opportunity to explore the process and causal relationships between climatic changes and the response of the vegetation. Thus, we propose here a realistic model scenario, from which we can extrapolate to global scales and improve our interpretations of results of global studies. 相似文献
4.
Abstract: New findings of dinosaur footprints are described from the Upper Jurassic Iouaridène ichnosite of Morocco. On the top of two surfaces, stratigraphically close to that bearing the famous Breviparopus taghbaloutensis trackways, two footprints were excavated and assigned to the ichnogenus Deltapodus . This ichnogenus is well known from the Middle Jurassic of Yorkshire and also occurs in Upper Jurassic deposits from Iberia and the United States. This finding represents the first record of Deltapodus from Africa. These footprints, probably produced by stegosaurian dinosaurs, add new data on the distribution of this type of dinosaur and on the connection between the northern and southern margin of Tethys. 3D models have been generated to allow more detailed studies and to record these unique footprints. 相似文献
5.
JULES ANGST THOMAS D. MEYER ROLF ADOLFSSON PETER SKEPPAR MAURO CARTA FRANCO BENAZZI RU‐BAND LU YI‐HSUAN WU HAI‐CHEN YANG CHENG‐MEI YUAN PAOLO MORSELLI PETER BRIEGER JUDITH KATZMANN INES ALICE TEIXEIRA LEÃO JOSÉ ALBERTO DEL PORTO DORIS HUPFELD MORENO RICARDO A. MORENO ODEILTON T. SOARES EDUARD VIETA ALEX GAMMA 《World psychiatry》2010,9(1):41-49
This study examined the transcultural robustness of a screening instrument
for hypomania, the Hypomania Checklist-32, first revised version (HCL-32 R1).
It was carried out in 2606 patients from twelve countries in five geographic
regions (Northern, Southern and Eastern Europe, South America and East Asia).
In addition, GAMIAN Europe contributed data from its members. Exploratory
and confirmatory factor analyses were used to examine the transregional stability
of the measurement properties of the HCL-32 R1, including the influence of
sex and age as covariates. Across cultures, a two-factor structure was confirmed:
the first factor (F1) reflected the more positive aspects of hypomania (being
more active, elated, self-confident, and cogni-tively enhanced); the second
factor (F2) reflected the more negative aspects (being irritable, impulsive,
careless, more substance use). The measurement properties of the HCL-32 R1
were largely invariant across cultures. Only few items showed transcultural
differences in their relation to hypomania as measured by the test. F2 was
higher among men and in more severe manic syndromes; F1 was highest in North
and East Europe and lowest in South America. The scores decreased slightly
with age. The frequency of the 32 items showed remarkable similarities across
geographic areas, with two excep-tions: South Europeans had lower symptom
frequencies in general and East Europeans higher rates of substance use. These
findings support the interna-tional applicability of the HCL-32 R1 as a screening
instrument for hypomania. 相似文献
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JOSEP PE
UELAS PATRICIA PRIETO CLAUS BEIER CARLA CESARACCIO PAOLO
De ANGELIS GIOVANBATTISTA
De DATO BRIDGET A. EMMETT MARC ESTIARTE JNOS GARADNAI ANTONIE GORISSEN EDIT KOVCS LNG GY
RGY KR
EL‐DULAY LAURA LLORENS GRAZIA PELLIZZARO TORBEN RIIS‐NIELSEN INGER K. SCHMIDT COSTANTINO SIRCA ALWYN SOWERBY DONATELLA SPANO ALBERT TIETEMA 《Global Change Biology》2007,13(12):2563-2581
We used a nonintrusive field experiment carried out at six sites – Wales (UK), Denmark (DK), the Netherlands (NL), Hungary (HU), Sardinia (Italy – IT), and Catalonia (Spain – SP) – along a climatic and latitudinal gradient to examine the response of plant species richness and primary productivity to warming and drought in shrubland ecosystems. The warming treatment raised the plot daily temperature by ca. 1 °C, while the drought treatment led to a reduction in soil moisture at the peak of the growing season that ranged from 26% at the SP site to 82% in the NL site. During the 7 years the experiment lasted (1999–2005), we used the pin‐point method to measure the species composition of plant communities and plant biomass, litterfall, and shoot growth of the dominant plant species at each site. A significantly lower increase in the number of species pin‐pointed per transect was found in the drought plots at the SP site, where the plant community was still in a process of recovering from a forest fire in 1994. No changes in species richness were found at the other sites, which were at a more mature and stable state of succession and, thus less liable to recruitment of new species. The relationship between annual biomass accumulation and temperature of the growing season was positive at the coldest site and negative at the warmest site. The warming treatment tended to increase the aboveground net primary productivity (ANPP) at the northern sites. The relationship between annual biomass accumulation and soil moisture during the growing season was not significant at the wettest sites, but was positive at the driest sites. The drought treatment tended to reduce the ANPP in the NL, HU, IT, and SP sites. The responses to warming were very strongly related to the Gaussen aridity index (stronger responses the lower the aridity), whereas the responses to drought were not. Changes in the annual aboveground biomass accumulation, litterfall, and, thus, the ANPP, mirrored the interannual variation in climate conditions: the most outstanding change was a decrease in biomass accumulation and an increase in litterfall at most sites during the abnormally hot year of 2003. Species richness also tended to decrease in 2003 at all sites except the cold and wet UK site. Species‐specific responses to warming were found in shoot growth: at the SP site, Globularia alypum was not affected, while the other dominant species, Erica multiflora, grew 30% more; at the UK site, Calluna vulgaris tended to grow more in the warming plots, while Empetrum nigrum tended to grow less. Drought treatment decreased plant growth in several studied species, although there were some species such as Pinus halepensis at the SP site or C. vulgaris at the UK site that were not affected. The magnitude of responses to warming and drought thus depended greatly on the differences between sites, years, and species and these multiple plant responses may be expected to have consequences at ecosystem and community level. Decreases in biodiversity and the increase in E. multiflora growth at the SP site as a response to warming challenge the assumption that sensitivity to warming may be less well developed at more southerly latitudes; likewise, the fact that one of the studied shrublands presented negative ANPP as a response to the 2003 heat wave also challenges the hypothesis that future climate warming will lead to an enhancement of plant growth and carbon sequestration in temperate ecosystems. Extreme events may thus change the general trend of increased productivity in response to warming in the colder sites. 相似文献
9.
Effect of Adjuvants on the Antibody Response to a Hapten on a Thymus-independent Carrier 总被引:3,自引:0,他引:3
PAOLO DEL GUERCIO 《Nature: New biology》1972,238(85):213-215
IT has been demonstrated in mice that levan (polyfructose), an antigen which interacts only with B lymphocytes1, can function as a carrier and produce a thymus-independent response to dinitrophenol (DNP)2. Using this conjugate, antibody-production against the hapten is totally unaffected in thymectomized animals and is abolished in mice tolerant to levan. The DNP-levan conjugate produces only 19S antibody against DNP. 相似文献
10.
FEDERICO BRILLI PAOLO CICCIOLI MASSIMILIANO FRATTONI MARCO PRESTININZI ANTONIO FRANCO SPANEDDA & FRANCESCO LORETO 《Plant, cell & environment》2009,32(5):542-552
Chrysomela populi beetles feed on poplar leaves and extensively damage plantations. We investigated whether olfactory cues orientate landing and feeding. Young, unexpanded leaves of hybrid poplar emit constitutively a blend of monoterpenes, primarily ( E )- β -ocimene and linalool. This blend attracts inexperienced adults of C. populi that were not previously fed with poplar leaves. In mature leaves constitutively emitting isoprene, insect attack induces biosynthesis and emission of the same blend of monoterpenes, but in larger amount than in young leaves. The olfactometric test indicates that inexperienced beetles are more attracted by adult than by young attacked leaves, suggesting that attraction by induced monoterpenes is dose dependent. The blend does not attract adults that previously fed on poplar leaves. Insect-induced emission of monoterpenes peaks 4 d after the attack, and is also detected in non-attacked leaves. Induced monoterpene emission is associated in mature leaves with a larger decrease of isoprene emission. The reduction of isoprene emission is faster than photosynthesis reduction in attacked leaves, and also occurs in non-attacked leaves. Insect-induced monoterpenes are quickly and completely labelled by 13 C. It is speculated that photosynthetic carbon preferentially allocated to constitutive isoprene in healthy leaves is in part diverted to induced monoterpenes after the insect attack. 相似文献