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561.
A biallelic, unifactorial, sexual incompatibility system, consisting of two mating types, is characteristic of the ascomycetous yeasts, such asSaccharomyces cerevisiae. In addition to the biallelic system, the basidiomycetous yeasts,Rhodosporidium andLeucosporidium have a multiple allelic bifactorial system with 2 A and 2B factors for a total of four mating types. This report presents evidence for an increase in this number of mating types inLeucosporidium scottii due to the presence of a minimum of 5 A and 3 B specificities with linked loci at each factor. These results indicate that sexual incompatibility system in basidiomycetous yeasts is similar to that found in other basidiomycetes such asSchizophyllum commune. 相似文献
562.
The sexual speciesSporidiobolus salmonicolor andSporidiobolus pararoseus spp. nov. are described as heterothallic species in the genusSporidiobolus, a genus consisting of two homothallic species,Sporidiobolus johnsonii andSporidiobolus ruinenii. The four species are compared and a key to the genus is presented. As a taxonomic correctionSporobolomyces pararoseus nom. nud. is reported as a synonym ofSporobolomyces shibatanus. 相似文献
563.
G Gigli M Casu G Paganini M Colombano A Campostano F Merlo G Lamedica 《Bollettino della Società italiana di biologia sperimentale》1991,67(3):245-251
24 hour pressure monitoring is a newly developing technique potentially yielding important informations in hypertensive patients. Numerous automated devices are available whose performance characteristics are poorly documented. To evaluate an automated sphygmomanometer commonly used in our Division (Omega 1400, Invivo Research Laboratories), we performed a series of measurements, simultaneously recording blood pressure in the opposite arm with a common sphygmomanometer. Each measure was then repeated reversing the position of the two devices (manual and automated), thus abolishing possible differences between the two arms. We observed a mean underestimation of 1.90 mmHg of systolic pressure and of 4.82 mmHg of diastolic blood pressure by the automated device. We conclude that the device by us evaluated is not advisable in the basal blood pressure evaluation, but useful in monitoring inpatients. 相似文献
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Federica Bono Paola Savoia Adele Guglielmi Massimo Gennarelli Giovanna Piovani Sandra Sigala Damiana Leo Stefano Espinoza Raul R. Gainetdinov Paola Devoto PierFranco Spano Cristina Missale Chiara Fiorentini 《Molecular neurobiology》2018,55(2):1054-1067
The role of dopamine D2 and D3 receptors (D2R/D3R), located on midbrain dopaminergic (DA) neurons, in the regulation of DA synthesis and release and in DA neuron homeostasis has been extensively investigated in rodent animal models. By contrast, the properties of D2R/D3R in human DA neurons have not been elucidated yet. On this line, the use of human-induced pluripotent stem cells (hiPSCs) for producing any types of cells has offered the innovative opportunity for investigating the human neuronal phenotypes at the molecular levels. In the present study, hiPSCs generated from human dermal fibroblasts were used to produce midbrain DA (mDA) neurons, expressing the proper set of genes and proteins typical of authentic, terminally differentiated DA neurons. In this model, the expression and the functional properties of the human D2R/D3R were investigated with a combination of biochemical and functional techniques. We observed that in hiPSC-derived mDA neurons, the activation of D2R/D3R promotes the proliferation of neuronal progenitor cells. In addition, we found that D2R/D3R activation inhibits nicotine-stimulated DA release and exerts neurotrophic effects on mDA neurons that likely occur via the activation of PI3K-dependent mechanisms. Furthermore, D2R/D3R stimulation counteracts both the aggregation of alpha-synuclein induced by glucose deprivation and the associated neuronal damage affecting both the soma and the dendrites of mDA neurons. Taken together, these data point to the D2R/D3R-related signaling events as a biochemical pathway crucial for supporting both neuronal development and survival and protection of human DA neurons. 相似文献
567.
Seep Arora Adele Jing Ying Lam Christine Cheung Evelyn K. F. Yim Yi-Chin Toh 《Biotechnology and bioengineering》2019,116(5):i-i
Human pluripotent stem cell-derived endothelial cells (hPSC-ECs) present an attractive alternative to primary EC sources for vascular grafting. However, there is a need to mature them towards either an arterial or venous subtype. A vital environmental factor involved in the arteriovenous specification of ECs during early embryonic development is fluid shear stress; therefore, there have been attempts to employ adult arterial shear stress conditions to mature hPSC-ECs. However, hPSC-ECs are naïve to fluid shear stress, and their shear responses are still not well understood. Here, we used a multiplex microfluidic platform to systematically investigate the dose-time shear responses on hPSC-EC morphology and arterial-venous phenotypes over a range of magnitudes coincidental with physiological levels of embryonic and adult vasculatures. The device comprised of six parallel cell culture chambers that were individually linked to flow-setting resistance channels, allowing us to simultaneously apply shear stress ranging from 0.4 to 15 dyne/cm 2. We found that hPSC-ECs required up to 40 hr of shear exposure to elicit a stable phenotypic change. Cell alignment was visible at shear stress <1 dyne/cm 2, which was independent of shear stress magnitude and duration of exposure. We discovered that the arterial markers NOTCH1 and EphrinB2 exhibited a dose-dependent increase in a similar manner beyond a threshold level of 3.8 dyne/cm 2, whereas the venous markers COUP-TFII and EphB4 expression remained relatively constant across different magnitudes. These findings indicated that hPSC-ECs were sensitive to relatively low magnitudes of shear stress, and a critical level of ~4 dyne/cm 2 was sufficient to preferentially enhance their maturation into an arterial phenotype for future vascular tissue engineering applications. 相似文献
568.
Federico Napolitano Rossella Merone Adele Abbate Virginia Ammendola Emma Horncastle Francesca Lanzaro Marialuisa Esposito Alessandra Maria Contino Roberta Sbrocchi Andrea Sommella Joshua D. Duncan Joseph Hinds Richard A. Urbanowicz Armin Lahm Stefano Colloca Antonella Folgori Jonathan K. Ball Alfredo Nicosia Benjamin Wizel Stefania Capone Alessandra Vitelli 《PLoS neglected tropical diseases》2021,15(4)
569.
Three different methods to standardize biofilm removal for in situ sanitary control of closed surfaces in the food industry have been developed and compared, i.e. sonication, enzymatic treatment and a combined treatment which involved the application of ultrasound to enzyme preparations. The biofilm studied was an Escherichia coli model biofilm, made with milk on stainless steel sheets. Plate counting and epifluorescence microscopy were used to assess the efficiency of each treatment. The results are expressed in percentages, 100% denoting total removal, obtained with a flat ultrasonic transducer (T1) developed and presented in a previous study. The application of ultrasound by a patented curved transducer, T2 (10 s, 40 kHz), specifically devised for closed surfaces, was not sufficient to completely remove the biofilm (30 ± 7%). This biofilm was dislodged by two proteolytic enzyme preparations tested by immersion, viz. a 15‐min application of protease (84±1%) and a 30‐min trypsin application (95±8%). Using a combined treatment, the results showed a synergism between ultrasonic waves and proteolytic or glycolytic enzyme preparations, with removal of a significant amount of biofilm, i.e. 61–96% depending on the conditions tested, i.e. two to three times greater compared to sonication alone (30%). This application was in agreement with an industrial control, i.e. a good reproducible recovery of the biofilm in 10 s compared with 30 or 15 min with the enzyme alone. 相似文献