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991.
Marcello Cantini Maria Lina Massimino Claudia Catani Rosario Rizzuto Marisa Brini Ugo Carraro 《In vitro cellular & developmental biology. Animal》1994,30(2):131-133
Summary A large bulk of experimental evidence (15) suggests that myogenic cell transfer can be regarded as a promising therapeutic
approach in the cure of inherited pathologies. In particular, it has been shown that primary myoblasts obtained from embryonic
or neonatal muscles allows the recovery of the normal phenotype in defective muscle tissues. The utilization of this approach
in clinical settings still bears heavy limitations. Apart from the legal and ethical difficulties, the use of muscles obtained
from aborted fetus is challenged by a large risk of rejection, due to the incompatibility between donor and recipient. In
this context based on the genetic alteration and reimplanting of the patient’s own satellite cells, appears an approach attractive.
Myoblasts derived from satellite cells are the obligate candidates for experiments, but the production of sufficient cell
numbers is a major problem. Local anesthetics [Bupivacaine (1-n-butyl-DL-piperidine-2-carboxylic acid-2, 6-dimethyl anilide
hydrochloride) and related molecules] had been used to induce myofiber damage (and thus satellite cells proliferation) and
thereby may represent a tool for increasing the yield of myoblasts from adult muscles (1,9,17). We will show that satellite
cells obtained from adult muscles after bupivacaine injection can be transfected in vitro and that the transfected gene is
expressed in vitro and in vivo, after reimplantation of the modified myoblasts in recipient muscles. 相似文献
992.
Eleonora Kumer Mario Berveglieri Marisa Cova Ida Magri Michela Mascis 《Aerobiologia》1996,12(1):197-200
The microbiological quality of indoor air is creating an increasing interest especially as far as places at risk such as hospitals, clinics, medical and odontological surgeries are concerned. Working with the odontologists of our province we have been carrying out a research aimed at preventing cross-infection in odontology. Data obtained from the microbiological analysis of the air in 36 surgeries using S.A.S. were discussed during the V National Congress of Aerobiology. During that congress the need of setting a standardized technique of air sampling in indoor environments emerged and two routes have been identified: (1) the gravimetric technique on open plate exposed for an hour close to the dental unit and (2) the use of the volumetric sampler which gives qualitative data expressed as colonies forming units per cubic metre of air. However, both of these techniques present some problems: using the first a loss of micro-organisms has been noticed due to the variability of the air fluxes and the different weight of the biological particles; using the second one the bacterial charge is also undervalued, because of the stress suffered by the bacteria with the use of the volumetric sampler. In the light of these statements we decided to use both in dental surgeries to be able to compare the results obtained. Our project is expected to carry out at least one inspection and the relative sampling (indoor air, water of the dental unit, air of the syringe, disinfectant solution, surface tampons, biological test of sterility) in each dental surgery in the territory of our health Unit, located in Ferrara, Northern Italy. 相似文献
993.
Intramammary immunization with live-attenuated Staphylococcus aureus: microbiological and immunological studies in a mouse mastitis model 总被引:1,自引:0,他引:1
Verónica García Marisa Gómez Mercedes Iglesias Norberto Sanjuan Magdalena Gherardi M. Cristina Cerquetti Daniel Sordelli 《FEMS immunology and medical microbiology》1996,14(1):45-51
Abstract Mammary infection was induced in lactating mice by intramammary injection of Staphylococcus aureus . Histopathological analysis revealed infiltration and lesions of varying magnitude that were still apparent 21 days after the challenge. Concomitantly, viable S. aureus was recovered from infected mammary glands. Mice were immunized by the intramammary route with 5 × 106 colony forming units of a temperature-sensitive mutant of S. aureus and subsequently received a boosting injection seven days later. On day 14 mice were challenged by the intramammary route with the wild-type strain. Intramammary immunization induced a significant increase in milk IgA ( P < 0.05), serum IgG ( P < 0.05) and serum IgA ( P < 0.05) on the day of the challenge, when compared with non-immunized mice. Immunization decreased significantly ( P < 0.01) the number of S. aureus colony forming units recovered 96 h after intramammary challenge. In conclusion, the feasibility of immunizing locally with temperature-sensitive S. aureus to induce immunity in the mouse mammary gland was demonstrated. The mouse model of mastitis is proposed as a useful system for screening temperature-sensitive S. aureus strains to be utilized in the development of a vaccine. 相似文献
994.
Mechanism of action of camphoryl‐benzene sulfonamide derivative on glucose uptake in adipose tissue
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995.
Domenico Cieri Mattia Vicario Francesca Vallese Beatrice DOrsi Paola Berto Alessandro Grinzato Cristina Catoni Diego De Stefani Rosario Rizzuto Marisa Brini Tito Calì 《生物化学与生物物理学报:疾病的分子基础》2018,1864(10):3247-3256
Intracellular neurofibrillary tangles (NFT) composed by tau and extracellular amyloid beta (Aβ) plaques accumulate in Alzheimer's disease (AD) and contribute to neuronal dysfunction. Mitochondrial dysfunction and neurodegeneration are increasingly considered two faces of the same coin and an early pathological event in AD. Compelling evidence indicates that tau and mitochondria are closely linked and suggests that tau-dependent modulation of mitochondrial functions might be a trigger for the neurodegeneration process; however, whether this occurs either directly or indirectly is not clear. Furthermore, whether tau influences cellular Ca2+ handling and ER-mitochondria cross-talk is yet to be explored. Here, by focusing on wt tau, either full-length (2N4R) or the caspase 3-cleaved form truncated at the C-terminus (2N4RΔC20), we examined the above-mentioned aspects. Using new genetically encoded split-GFP-based tools and organelle-targeted aequorin probes, we assessed: i) tau distribution within the mitochondrial sub-compartments; ii) the effect of tau on the short- (8–10?nm) and the long- (40–50?nm) range ER-mitochondria interactions; and iii) the effect of tau on cytosolic, ER and mitochondrial Ca2+ homeostasis. Our results indicate that a fraction of tau is found at the outer mitochondrial membrane (OMM) and within the inner mitochondrial space (IMS), suggesting a potential tau-dependent regulation of mitochondrial functions. The ER Ca2+ content and the short-range ER-mitochondria interactions were selectively affected by the expression of the caspase 3-cleaved 2N4RΔC20 tau, indicating that Ca2+ mis-handling and defects in the ER-mitochondria communications might be an important pathological event in tau-related dysfunction and thereby contributing to neurodegeneration. Finally, our data provide new insights into the molecular mechanisms underlying tauopathies. 相似文献
996.
Yazmín Arellano Eugene Bratoeff Yvonne Heuze Marisol Bravo Juan Soriano Marisa Cabeza 《Bioorganic & medicinal chemistry》2018,26(14):4058-4064
It is known that the growth of prostate metastatic bone tumor depends on androgens, and tumor formation can start from migratory malignant cells produced in that organ. These cells exhibit grater type 1 5α-reductase (5α-R1) activity than type 2 5α-reductase. Noteworthy, both isozymes convert testosterone (T) to the more active androgen dihydrotestosterone (DHT) in the target tissues.Thus, in order to potentially improve the prognosis of this disease, in this work, seven derivatives of 17-(1H-benzimidazol-1-yl)-16-formillandrosta-5,16-dien-3β-yl benzoate (4a–f) and 17-(1H-benzimidazol-1-yl)-3-hydroxy-16-formylandrost-5,16-diene (4) were synthesized, characterized and identified as inhibitors of type 1 5α-reductase (5αR1). These derivatives having the advantage of improved plasma half-life.The inhibitory activity of the compounds towards 5α-R1 isoenzyme was determined by conversion of T into DHT in the presence or absence of compounds 4, 4a–f. Further, in vivo experiments were also carried out, treating gonadectomized hamsters with T and/or 4, 4a–f and evaluating their effect on the diameter of hamster flank organs and on the weight of the prostatic and seminal vesicles. Results indicated that compounds 4, 4b, 4c, served as in vitro inhibitors of the enzyme 5α-R1 and pharmacological experiments showed that 4 and derivatives 4a–f decreased the diameter of the flank glands, the weight of the prostate and seminal vesicles of treated hamsters without any appreciable toxicity during observation. Noteworthy the fact that compound 4 is the product, in all cases, of the hydrolysis of the series of esters 4a–f, thus they can serve as precursors (prodrugs) of the active form 4. 相似文献
997.
Identification of murine phosphodiesterase 5A isoforms and their functional characterization in HL‐1 cardiac cell line
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Federica Campolo Alessandra Zevini Silvia Cardarelli Lucia Monaco Federica Barbagallo Manuela Pellegrini Marisa Cornacchione Antonio Di Grazia Valeria De Arcangelis Daniele Gianfrilli Mauro Giorgi Andrea Lenzi Andrea M. Isidori Fabio Naro 《Journal of cellular physiology》2018,233(1):325-337
Phosphodiesterase 5A (PDE5A) specifically degrades the ubiquitous second messenger cGMP and experimental and clinical data highlight its important role in cardiac diseases. To address PDE5A role in cardiac physiology, three splice variants of the PDE5A were cloned for the first time from mouse cDNA library (mPde5a1, mPde5a2, and mPde5a3). The predicted amino acidic sequences of the three murine isoforms are different in the N‐terminal regulatory domain. mPDE5A isoforms were transfected in HEK293T cells and they showed high affinity for cGMP and similar sensitivity to sildenafil inhibition. RT‐PCR analysis showed that mPde5a1, mPde5a2, and mPde5a3 had differential tissue distribution. In the adult heart, mPde5a1 and mPde5a2 were expressed at different levels whereas mPde5a3 was undetectable. Overexpression of mPDE5As induced an increase of HL‐1 number cells which progress into cell cycle. mPDE5A1 and mPDE5A3 overexpression increased the number of polyploid and binucleated cells, mPDE5A3 widened HL‐1 areas, and modulated hypertrophic markers more efficiently respect to the other mPDE5A isoforms. Moreover, mPDE5A isoforms had differential subcellular localization: mPDE5A1 was mainly localized in the cytoplasm, mPDE5A2 and mPDE5A3 were also nuclear localized. These results demonstrate for the first time the existence of three PDE5A isoforms in mouse and highlight their potential role in the induction of hypertrophy. 相似文献
998.
Cristine Betzer Louise Berkhoudt Lassen Anders Olsen Rikke Hahn Kofoed Lasse Reimer Emil Gregersen Jin Zheng Tito Calì Wei‐Ping Gai Tong Chen Arne Moeller Marisa Brini Yuhong Fu Glenda Halliday Tomasz Brudek Susana Aznar Bente Pakkenberg Jens Peter Andersen Poul Henning Jensen 《EMBO reports》2018,19(5)
Aggregation of α‐synuclein is a hallmark of Parkinson's disease and dementia with Lewy bodies. We here investigate the relationship between cytosolic Ca2+ and α‐synuclein aggregation. Analyses of cell lines and primary culture models of α‐synuclein cytopathology reveal an early phase with reduced cytosolic Ca2+ levels followed by a later Ca2+ increase. Aggregated but not monomeric α‐synuclein binds to and activates SERCA in vitro, and proximity ligation assays confirm this interaction in cells. The SERCA inhibitor cyclopiazonic acid (CPA) normalises both the initial reduction and the later increase in cytosolic Ca2+. CPA protects the cells against α‐synuclein‐aggregate stress and improves viability in cell models and in Caenorhabditis elegans in vivo. Proximity ligation assays also reveal an increased interaction between α‐synuclein aggregates and SERCA in human brains affected by dementia with Lewy bodies. We conclude that α‐synuclein aggregates bind SERCA and stimulate its activity. Reducing SERCA activity is neuroprotective, indicating that SERCA and down‐stream processes may be therapeutic targets for treating α‐synucleinopathies. 相似文献
999.
Leonardo A. Piazza Daniela López Mariana P. Silva Marisa J. López Rivilli Mónica G. Tourn Juan J. Cantero Ana L. Scopel 《化学与生物多样性》2018,15(3)
The distribution and ultrastructure of capitate glandular trichomes (GTs) in Flourensia species (Asteraceae) have been recently elucidated, but their metabolic activity and potential biological function remain unexplored. Selective nonvolatile metabolites from isolated GTs were strikingly similar to those found on leaf surfaces. The phytotoxic allelochemical sesquiterpene (–)‐hamanasic acid A ((–)‐HAA) was the major constituent (ca. 40%) in GTs. Although GTs are quaternary ammonium compounds (QACs)‐accumulating species, glycine betaine was not found in GTs; it was only present in the leaf mesophyll. Two (–)‐HAA accompanying surface secreted products: compounds 4‐hydroxyacetophenone (piceol; 1 ) and 2‐hydroxy‐5‐methoxyacetophenone ( 2 ), which were isolated and fully characterized (GC/MS, NMR), were present in the volatiles found in GTs. The essential oils of fresh leaves revealed ca. 33% monoterpenes, 26% hydrocarbon‐ and 30% oxygenated sesquiterpenes, most of them related to cadinene and bisabolene derivatives. Present results suggest a main role of GTs in determining the volatile and nonvolatile composition of F. campestris leaves. Based on the known activities of the compounds identified, it can be suggested that GTs in F. campestris would play key ecological functions in plant‐pathogen and plant‐plant interactions. In addition, the strikingly high contribution of compounds derived from cadinene and bisabolene pathways, highlights the potential of this species as a source of high‐valued bioproducts. 相似文献
1000.
Adolfo Porcellini Annunziata Manna Marisa Manna Luciano Moretti Fabrizio Agostinelli Guido Lucarelli 《Cryobiology》1981,18(6):541-546
Bone marrow cells collected from patients with hematologic malignancies were cryopreserved using DMSO as a cryoprotective agent. The growth kinetics of hemopoietic stem cells frozen to −196 °C was monitored immediately after thawing by the semisolid agar CFU-C assay and two different methods of cell reconstitution were compared. In the first procedure, thawed cells were plated after the removal of DMSO by washing the cell suspension; in the second, cell suspensions were cultured after a simple 1:1 dilution of DMSO with medium. The numbers of CFU-C per 2 × 105 cells plated was higher by washing out the DMSO in all the groups studied. However, the absolute numbers of CFU-C contained in the whole ampoules after the freezing procedures was approximately the same using both methods. It is concluded that washing the cells only apparently yielded a better cloning efficiency, suggesting that such a procedure led to a higher mature nucleated cell loss with the consequence of a CFU-C concentration. This trend seems particularly evident in cells from the AML and CML patients. 相似文献