327 research outputs found

    Heterocysts of Rivularia Type for Interpreting a Palaeoenvironmental Context of the Late Quaternary in Northern Italy

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    This paper presents new results on a quali-quantitative analysis of the heterocysts of the Rivularia type as a key bioindicator informative on local eutrophic conditions. The Rivularia type is usually reported in palynological analyses due to the thick, multilayered envelope that ensures the preservation of heterocysts in sediments. Samples come from two continuous terrestrial cores (N-S3: 77 samples, C-S1: 20 samples) drilled in the area surrounding the Bronze Age site of the Terramara S. Rosa di Poviglio (Po Plain; N Italy) and spanning at least over the last 15 ka years. Concentrations and percentages of the Rivularia type, combined with pollen curves of wet environments, describe local variability and rapid changes in ecological conditions over the millennia of deposition. Given the abundance and diversity of heterocysts of the Rivularia type in the studied samples, this paper attempts to group these cells based on morphology (ellipsoidal or elongated) and the state of preservation of the sheaths (presence or absence). Actually, it is difficult to confirm a relationship between heterocyst morphologies and the presence of different cyanobacteria species. Increasingly accurate identification of heterocysts from biostratigraphical archives may improve the data available on these bioindicators for achieving more detailed decoding of wetland (and terrestrial) transformations. Since the Bronze Age and at the most recent levels, the Rivularia type may be a good indicator of the local presence of agriculture and livestock, which lead to trophic and water changes in the soil

    Pollen and Molecular Biomarkers from Sedimentary Archives in the Central Po Plain (N Italy): Assessing Their Potential to Deepen Changes in Natural and Agricultural Systems

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    This paper proposes to improve the information provided by biological indicators from sedimentary archives by integrating biomolecular techniques and botanical skills. This study repre sents a first proposal for combining pollen and biomolecular markers to detect land use and improve knowledge of past environmental change drivers. The specific aim of the research is to verify the relationship between miliacin (a pentacyclic triterpene methyl ether, usually interpreted as a broom corn millet biomarker) and Panicum pollen in three near-site stratigraphic sequences of the Terramara S. Rosa di Poviglio (Po Plain, N Italy). The three cores span the last ~15,000 years and potentially record the beginning of Panicum miliaceum cultivation attested in the area since at least the Bronze Age within the Terramare culture. Despite the fact that Panicum pollen grains were rare in the spectra and miliacin was barely detectable in most of the 31 samples selected for biomolecular analyses, their combined evidence testifies to the local presence of the plant. Panicum pollen and sedimentary miliacin suggest the adoption of millet crops during the Recent Bronze Age by the Terramare culture, when climatic instability led to the diversification of cereal crops and the shift to drought-tolerant varieties

    Multiporate Pollen of Poaceae as Bioindicator of Environmental Stress: First Archaeobotanical Evidence from the Early–Middle Holocene Site of Takarkori in the Central Sahara

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    This paper reports on the most ancient unusual morphological trait of the apertures of Poaceae pollen found in archaeological layers. In Poaceae, high levels of hybridization, polyploidy, apomixis, and multiporate pollen are often related. Multiple genomes in polyploids are critical for the adaptation of plant species to stresses and could be revealed by anomalies in pollen development. Therefore, the paleoenvironmental research can gain great benefits from identifying polyploids in past contexts by observing anomalous pollen morphology during pollen counts. The occurrence of multiporate pollen in Poaceae has also been related to special features of the ecology of the species showing this anomaly, as well as to climatic and environmental stresses experienced by Poaceae living in a given region. Multiporate and bi- or tri-porate instead of monoporate pollen grains have been observed in samples taken from Takarkori rockshelter, an archaeological site in southwestern Libya (central Sahara) that has been occupied between ~10,200 and ~4650 cal BP. Multiporate pollen was found in organic sands and coprolites of ovicaprines. On the basis of archaeobotanical research, this work aims to investigate whether the presence of supernumerary pores in Poaceae pollen may be an effect of both climatic/hydrological changes and continued anthropogenic pressure on the wild grasses living in the region. The presence of multiporate pollen reveals that Poaceae that lived in central Sahara tackled several kinds of stress during the early and middle Holocene. The Takarkori pollen record suggests that climate change could have played a major role in the early Holocene, while human pressure became stronger during the middle Holocene. The change in environmental conditions determined adaptive responses of polyploid grasses even in the form of multiporate pollen

    Robustness and modularity properties of a non-covalent DNA catalytic reaction

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    The biophysics of nucleic acid hybridization and strand displacement have been used for the rational design of a number of nanoscale structures and functions. Recently, molecular amplification methods have been developed in the form of non-covalent DNA catalytic reactions, in which single-stranded DNA (ssDNA) molecules catalyze the release of ssDNA product molecules from multi-stranded complexes. Here, we characterize the robustness and specificity of one such strand displacement-based catalytic reaction. We show that the designed reaction is simultaneously sensitive to sequence mutations in the catalyst and robust to a variety of impurities and molecular noise. These properties facilitate the incorporation of strand displacement-based DNA components in synthetic chemical and biological reaction networks

    Management and therapeutic response of a prostate ductal adenocarcinoma: a still unknown tumour?

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    Ductal adenocarcinoma is a rare subtype of prostate cancer with a worse prognosis.Histologically, it is characterized by the presence of tall, pseudostratified columnar epithelium with abundant cytoplasm organized in a papillary or cribriform-papillary pattern. Several clinical differences distinguish this subtype of prostate cancer by the conventional acinar adenocarcinoma: exophytic growth into the prostatic urethra, different clinical presentation, different sites of metastasis and more aggressiveness. The rarity of this tumour forced to base our knowledge on small case series or on individual case reports, and does not help to establish appropriate guidelines. Therefore, the diagnosis of this tumour masks clinical implications that are still not well-understood.We report the case of a 69-year-old Caucasian man with a diagnosis of pure prostate ductal adenocarcinoma that early developed multiple metastases after radical prostatectomy. The patient started hormonal therapy with a fast biochemical and radiologic (positron emission tomography-computed tomography, PET-CT) hormonal escape. Therefore, we took the decision to perform chemotherapy with Taxotere along with prednisolone with a relative stability of prostate-specific antigen (PSA) level, but a new PET-CT scan showed a further progression of the disease. Finally, the patient underwent therapy with Abiraterone acetate that did not stop the cancer progression.No therapeutic options available showed a good control of disease progression. PSA proved to be a poor marker while, on the contrary, PET-CT scan has proved to be particularly useful in the management of the disease progression. More efforts are required to add new knowledge about this tumour and assess what is known until now

    How do research intensive systems emerge in less developed areas? The case of mechatronics in the Italian southern region Apulia

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    Regional innovation systems (RISs) are increasingly emerging in less developed areas. Based on the case study of the mechatronic cluster in the Italian southern region, Apulia, this paper analyses how institutions have managed to promote the establishment of a RIS in disadvantaged areas. Through a longitudinal analysis over more than half a century, the Apulian case study shows that the creation of this RIS in less developed areas is the result of a dynamic process characterised by a multi-level governance, initially promoted by the central government through a top-down logic, and then integrated by action of local actors through a bottom-up approach. A key role is played by the regionalisation of innovation policies and by the strategic action of regional public institutions to promote the interaction among enterprises and universities. Our analysis highlights that several ingredients should simultaneously occur for a regional innovation policy to be effective. Any regional innovation strategy significantly lacking one of these core pre-conditions and ingredients is risky. Policy-makers should carefully study the opportunities and challenges arising from local contexts before embarking in ambitious place-based innovation strategies

    Retrospective analysis of mantle cell lymphoma: experience of the Gruppo Italiano per lo Studio dei Linfomi (GISL)

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    Background and Objective. Mantle cell lymphoma is a recently recognized histologic entity with specific biological and clinical features. Clinically, the reported unfavorable outcome of these patients has focused attention on this category of non-Hodgkin's lymphoma (NHL). Design and Methods. The slide specimens of 69 NHL patients, originally classified as Working Formulation (WF) group B and E, were reviewed. The clinical features at presentation, response to therapy, response duration and survival were analyzed in cases reclassified as MCL. The correlation between clinical and histologic characteristics and the final outcome was evaluated. Results. Out of 69 cases, 34 specimens were reclassified as MCL; in 6 patients, previously classified as WF group B, the nodular pattern was confirmed; in 2 instances the blastoid form was recognized. After a median follow-up of 35.7 months, the entire series displayed a median overall survival of 41.2 months; a significantly longer survival was associated with the nodular histologic pattern, IPI score <2, response achievement, and a higher Hb level. The vast majority of patients received anthracycline-containing combination chemotherapy. Complete remission rate was 38.8% and overall response rate was 67.6%; response achievement was significantly influenced only by Hb level. Median response duration was 23.3 months. Interpretation and Conclusions. The present study confirms the unfavorable clinical course of MCL and the possible need for an alternative therapeutic strategy for this NHL category. Therefore, the correct identification of MCL at diagnosis appears of relevance. (C)1998, Ferrata Storti Foundation

    Nitric oxide can function as either a killer molecule or an antiapoptotic effector in cardiomyocytes

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    AbstractCaspase enzymes are a family of cysteine proteases that play a central role in apoptosis. Recently, it has been demonstrated that caspases can be S-nitrosylated and inhibited by nitric oxide (NO). The present report shows that in chick embryo heart cells (CEHC), NO donor molecules such as S-nitroso-N-acetylpenicillamine (SNAP), S-nitrosoglutathione, spermine-NO or sodium nitroprusside inhibit caspase activity in both basal and staurosporine-treated cells. However, the inhibitory effect of NO donors on caspase activity is accompanied by a parallel cytotoxic effect, that precludes NO to exert its antiapoptotic capability. N-Acetylcysteine (NAC) at a concentration of 10 mM blocks depletion of cellular glutathione and cell death in SNAP-treated CEHC, but it poorly affects the ability of SNAP to inhibit caspase activity. Consequently, in the presence of NAC, SNAP attenuates not only caspase activity but also cell death of staurosporine-treated CEHC. These data show that changes in the redox environment may inhibit NO-mediated toxicity, without affecting the antiapoptotic capability of NO, mediated by inhibition of caspase enzymes. NO may thus be transformed from a killer molecule into an antiapoptotic agent
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