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71.
In vitro culture of Aloe Barbadensis Mill.: Micropropagation from vegetative meristems 总被引:4,自引:0,他引:4
Lucia Natali Isidro Castorena Sanchez Andrea Cavallini 《Plant Cell, Tissue and Organ Culture》1990,20(1):71-74
A method for rapid and highly effective plant micropropagation from vegetative meristems was established for Aloe barbadensis Mill. Plant micropropagation was achieved culturing apices on medium containing 1.1 M 2,4-dichlorophenoxyacetic acid and 2.3 M kinetin for 15–30 days. High morphogenetic ability was maintained by transferring explants (after 60 days) on media containing 0.11 M 2,4-dichlorophenoxyacetic acid and 2.2 M 6-benzylaminopurine. 相似文献
72.
73.
doi: 10.1111/j.1741‐2358.2011.00484.x Surface roughness of denture base and reline materials after disinfection by immersion in chlorhexidine or microwave irradiation Background: This study evaluated the effect of disinfection by immersion and microwave irradiation on the roughness of one denture base resin (Lucitone‐L) and five relining materials, three hard (Tokuyama Rebase II‐TR, New Truliner‐NT, Ufigel Hard‐UH) and two resilient (Trusoft‐T, Sofreliner‐S). Methods: Fifty specimens were made and divided into groups: CL2 specimens were brushed with 4% chlorhexidine (1 min), immersed in the same solution (10 min) and immersed in water (3 min); MW2 specimens were immersed in water and microwave irradiated (650W; 6 min); CL2 and MW2 specimens were disinfected twice; CL7 and MW7 specimens were submitted to seven cycles using chlorhexidine or microwave irradiation, respectively; W specimens were not disinfected and remained in water (37°C; 7 days). Results: Results were statistically analysed (p = 0.05) and revealed that, at baseline, the highest mean value was observed for T (p < 0.001). Material NT showed increase in roughness after the first (p = 0.003), second (p = 0.001), seventh (p = 0.000) cycles of microwave disinfection and after 7 days of immersion in water (p = 0.033). Conclusions: Resilient liner S presented significant increase in roughness after the second cycle of disinfection with chlorhexidine (p = 0.003). Material T exhibited significantly decreased roughness in group W (p = 0.010), while microwaving produced severe alterations on its surface. 相似文献
74.
Lucia Angélica Garcia-Camacho Alejandro Vargas-Ruiz Ernesto Marin-Flamand Hugo Ramírez-Álvarez Corrie Brown 《Microbiology and immunology》2020,64(5):366-376
Worldwide, many emerging porcine parvoviruses (PPVs) have been linked to porcine circovirus-2 (PCV2) associated disease (PCVAD), which includes post-weaning multi-systemic wasting syndrome (PMWS), PCV2-related reproductive failure (PCV2-RF), as well as other syndromes. To determine the DNA prevalence of PPVs and their relationship with PMWS and PCV2-RF in Mexico, 170 formalin-fixed paraffin-embedded tissues were selected from archival collections to detect PPVs using a nested polymerase chain reaction. The tissues were composed of 50 PMWS cases, 20 age-matched tissues from healthy pigs, 56 PCV2-related reproductive failure (PCV2+-RF) cases, and 44 PCV2--RF cases. Overall, PPV2 and PPV6 were the most prevalent species (90.0% and 74.7%, respectively). In 8–11 week old pigs, the highest prevalence was for PPV6 and PPV3. Concerning reproductive failure, the PCV2-affected farms had a significantly higher prevalence for PPV6 (61.6%) and PPV5 (36.4%) than the PCV2-unaffected farms (35.0% and 5.0%, respectively). The concurrent infection rate was high, being significant for PPV2/PPV4 and PPV1/PPV5 within the PMWS cases and for PPV6/PPV5 among the PCV2+-RF tissues. PPV5 showed a significant relationship with PMWS, whereas PPV5 and PPV6 were significant for PCVAD. The prevalence and coinfection rate of PPVs in Mexico were markedly higher than that described in other countries, denoting that PPV5 and PPV6 might have a potential role in PCVAD in Mexico. It is concluded that it is likely that the density population of pigs in Mexico is contributing to high PPV inter-species and PCV2 coinfections which might lead to a different pathogenic outcome. 相似文献
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Donato Santovito Virginia Egea Kiril Bidzhekov Lucia Natarelli Andr Mouro Xavier Blanchet Kanin Wichapong Maria Aslani Coy Brunßen Michael Horckmans Michael Hristov Arie Geerlof Esther Lutgens Mat J. A. P. Daemen Tilman Hackeng Christian Ries Triantafyllos Chavakis Henning Morawietz Ronald Naumann Philipp Von Hundelshausen Sabine Steffens Johan Duchêne Remco T. A. Megens Michael Sattler Christian Weber 《Autophagy》2020,16(12):2294
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78.
Elena Bausch Hella Kohlhof Svetlana Hamm Rolf Krauss Roland Baumgartner Lucia Sironi 《PloS one》2013,8(11)
Microtubule inhibitors are invaluable tools in cancer chemotherapy: taxanes and vinca alkaloids have been successfully used in the clinic over the past thirty years against a broad range of tumors. However, two factors have limited the effectiveness of microtubule inhibitors: toxicity and resistance. In particular, the latter is highly unpredictable, variable from patient to patient and is believed to be the cause of treatment failure in most cases of metastatic cancers. For these reasons, there is an increasing demand for new microtubule inhibitors that can overcome resistance mechanisms and that, at the same time, have reduced side effects. Here we present a novel microtubule inhibitor, 4SC-207, which shows strong anti-proliferative activity in a large panel of tumor cell lines with an average GI50 of 11nM. In particular, 4SC-207 is active in multi-drug resistant cell lines, such as HCT-15 and ACHN, suggesting that it is a poor substrate for drug efflux pumps. 4SC-207 inhibits microtubule growth in vitro and in vivo and promotes, in a dose dependent manner, a mitotic delay/arrest, followed by apoptosis or aberrant divisions due to chromosome alignment defects and formation of multi-polar spindles. Furthermore, preliminary data from preclinical studies suggest low propensity towards bone marrow toxicities at concentrations that inhibit tumor growth in paclitaxel-resistant xenograft models. In summary, our results suggest that 4SC-207 may be a potential anti-cancer agent. 相似文献
79.
José Rodrigues Coura Pedro Albajar Vi?as Lucia Maria Brum-Soares Andréa Silvestre de Sousa Sérgio Salles Xavier 《Memórias do Instituto Oswaldo Cruz》2013,108(8):1009-1013
A case-control study on the morbidity of Chagas heart disease was carried out in the
municipality of Barcelos in the microregion of the Rio Negro, state of Amazonas. One
hundred and six individuals, who were serologically positive for Trypanosoma
cruzi infection, as confirmed by at least two techniques with different
principles, were matched according to age and sex with an equal number of
seronegative individuals. The cases and controls were evaluated using an
epidemiological questionnaire and clinical, electrocardiograph and echocardiograph
examinations. In the seroepidemiological evaluation, 62% of the interviewees
recognised triatomines and most of them confirmed that they had seen these insects in
the piassava plantations of the riverside communities of the Negro River tributaries.
Of the seropositive patients, 25.8% affirmed that they had been stung by the
triatomines and 11.7% denied having been stung. The principal clinical manifestations
of the seropositive individuals were palpitations, chest pain and dyspnoea upon
effort. Cardiac auscultation revealed extrasystoles, bradycardia and systolic
murmurs. The electrocardiographic alterations were ventricular extrasystoles, left
and right bundle branch block, atrioventricular block and primary T wave alterations.
The echocardiogram was altered in 22.6% of the seropositive individuals and in 8.5%
of the seronegative individuals. 相似文献
80.
Luca Fontanesi Michela Colombo Lucia Tognazzi Emilio Scotti Luca Buttazzoni Stefania Dall’Olio Roberta Davoli Vincenzo Russo 《Molecular biology reports》2011,38(2):1425-1431
TBC1D1 [TBC1 (tre-2/USP6, BUB2, cdc16) domain family, member 1] is a Rab-GTPase-activating related protein implicated in regulating
the trafficking of glucose transporter 4 (GLUT4 or SLC2A4) storage vesicles to the cell surface in response to insulin and
AMPK-activating stimuli in skeletal muscle. Mutations in the human and mouse TBC1D1 genes confer risk of obesity or leanness. We identified five single nucleotide polymorphisms (SNPs) in the porcine TBC1D1 gene. One of them (FN677935:g.219G>A) was genotyped either by high resolution melting and PCR-RFLP analyses to study allele
frequencies in a few pig breeds and evaluate association with meat production and carcass traits in five groups of sib-tested
pigs of Italian Large White and Italian Duroc breeds. The g.219G>A SNP was associated (P < 0.05) with ham weight, back fat thickness and lean cuts content in Italian Large White and with visible intermuscular fat
in Italian Duroc pigs. 相似文献