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81.
Gonzalez EG Cunha RL Sevilla RG Ghanavi HR Krey G Bautista JM 《Molecular phylogenetics and evolution》2012,62(3):1013-1018
The group of small poor cods and pouts from the genus Trisopterus, belonging to the Gadidae family, comprises four described benthopelagic species that occur across the North-eastern Atlantic, from the Baltic Sea to the coast of Morocco, and the Mediterranean. Here, we combined molecular data from mitochondrial (cytochrome b) and nuclear (rhodopsin) genes to confirm the taxonomic status of the described species and to disentangle the evolutionary history of the genus. Our analyses supported the monophyly of the genus Trisopterus and confirmed the recently described species Trisopterus capelanus. A relaxed molecular clock analysis estimated an Oligocene origin for the group (∼30 million years ago; mya) indicating this genus as one of the most ancestral within the Gadidae family. The closure and re-opening of the Strait of Gibraltar after the Messinian Salinity Crisis (MSC) probably triggered the speciation process that resulted in the recently described T. capelanus. 相似文献
82.
SD Blaschko GR Cunha LS Baskin 《Differentiation; research in biological diversity》2012,84(3):261-268
External genitalia development occurs through a combination of hormone independent, hormone dependent, and endocrine pathways. Perturbation of these pathways can lead to abnormal external genitalia development. We review human and animal mechanisms of normal and abnormal external genitalia development, and we evaluate abnormal mechanisms that lead to hypospadias. We also discuss recent laboratory findings that further our understanding of animal models of hypospadias. 相似文献
83.
de Lima Prata K de Santis GC Orellana MD Palma PV Brassesco MS Covas DT 《Cytotherapy》2012,14(6):694-700
Background aimsMesenchymal stromal cells (MSC) are being used to treat and prevent a variety of clinical conditions. To be readily available, MSC must be cryopreserved until infusion. However, the optimal cryopreservation methods, cryoprotector solutions and MSC sensitivity to dimethyl sulfoxide (DMSO) exposure are unknown. This study investigated these issues.MethodsMSC samples were obtained from human umbilical cord (n = 15), expanded with Minimal Essential Medium-alpha (α-MEM) 10% human serum (HS), resuspended in 25 mL solution (HS, 10% DMSO, 20% hydroxyethyl starch) and cryopreserved using the BioArchive® system. After a mean of 18 ± 7 days, cell suspensions were thawed and diluted until a DMSO concentration of 2.5% was reached. Samples were tested for cell quantification and viability, immunophenotype and functional assays.ResultsPost-thaw cell recovery: 114 ± 2.90% (mean ± SEM). Recovery of viable cells: 93.46 ± 4.41%, 90.17 ± 4.55% and 81.03 ± 4.30% at 30 min, 120 min and 24 h post-thaw, respectively. Cell viability: 89.26 ± 1.56%, 72.71 ± 2.12%, 70.20 ± 2.39% and 63.02 ± 2.33% (P < 0.0001) pre-cryopreservation and 30 min, 120 min and 24 h post-thaw, respectively. All post-thaw samples had cells that adhered to culture bottles. Post-thaw cell expansion was 4.18 ± 0.17 ×, with a doubling time of 38 ± 1.69 h, and their capacity to inhibit peripheral blood mononuclear cells (PBMC) proliferation was similar to that observed before cryopreservation. Differentiation capacity, cell-surface marker profile and cytogenetics were not changed by the cryopreservation procedure.ConclusionsA method for cryopreservation of MSC in bags, in xenofree conditions, is described that facilitates their clinical use. The MSC functional and cytogenetic status and morphologic characteristics were not changed by cryopreservation. It was also demonstrated that MSC are relatively resistant to exposure to DMSO, but we recommend cell infusion as soon as possible. 相似文献
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Particular RNA fragments obtained by action of pancreatic ribonuclease on purified RNAs originating from species totally unrelated to Agrobacterium tumefaciens (Escherichia coli, rabbit, monkey) are capable of inducing the formation of transplantable tumorous tissue when introduced at wounded sites in inverted stems of Datura stramonium maintained under axenic conditions on a medium containing auxin and kinetin. Reovirus RNA and a small size RNA (5–6 S) isolated from RNA bound RNA directed DNA polymerase from Escherichia coli also induced the appearance of tumorous tissues which grow on solid synthetic medium in the absence of auxin and kinetin. 相似文献
87.
Felipe F.B. Tuon Khaiany Lino Florencio Clóvis Arns da Cunha Jaime Luis Lopes Rocha 《Revista iberoamericana de micología》2018,35(2):63-67
Background
Posaconazole is used for the prophylaxis of invasive fungal disease (IFD). Previous studies have shown it to be cost-effective compared to fluconazole/itraconazole. However, posaconazole has never been economically evaluated in developing countries.Aims
The aim of the present study was to perform a cost-effectiveness analysis of posaconazole compared to fluconazole in public (SUS) and private hospitals (PHS) in Brazil.Methods
A cost-effectiveness simulation was conducted on the basis of a pivotal study on the use of posaconazole in acute myeloid leukemia (AML) patients, adjusting the costs to Brazilian data.Results
A pharmacoeconomic analysis was performed on a hypothetical sample of 100 patients in each drug group. The total cost of posaconazole use alone was USD$ 220,656.31, whereas that for fluconazole was USD$ 83,875.00. Our results showed that patients with IFD remain hospitalized for an additional 12 days, at an average cost of USD$ 850.85 per patient per day. The total money spent by PHS for 100 patients for 100 days was USD$ 342,318.00 for the posaconazole group and USD$ 302,039.00 for the fluconazole group. An analysis of sensitivity (10%) revealed no intergroup difference.Conclusions
In Brazil posaconazole is cost-effective, and should be considered for the prophylaxis of patients with AMD/myelodysplasia (AML/MDS) undergoing chemotherapy. 相似文献88.
The initial steps in taste and olfaction result from the activation by
chemical stimuli of taste receptor cells (TRCs) and olfactory receptor
neurons (ORNs). In parallel with these two pathways is the chemosensitive
trigeminal pathway whose neurons terminate in the oral and nasal cavities
and which are activated by many of the same chemical stimuli that activate
TRCs and ORNs. In a recent single unit study we investigated the responses
of rat chorda tympani and glossopharnygeal neurons to a variety of
bitter-tasting alkaloids, including nicotine, yohimbine, quinine,
strychnine and caffeine, as well as capsaicin, the pungent ingredient in
hot pepper. Here we apply many of these same compounds to cultured rat
trigeminal ganglion (TG) neurons and measure changes in intracellular
calcium [Ca2+]i to determine whether TG neurons will respond to these same
compounds. Of the 89 neurons tested, 34% responded to 1 mM nicotine, 7% to
1 mM caffeine, 5% to 1 mM denatonium benzoate, 22% to 1 mM quinine
hydrochloride, 18% to 1 mM strychnine and 55% to 1 microM capsaicin. These
data suggest that neurons from the TG respond to the same bitter-tasting
chemical stimuli as do TRCs and are likely to contribute information sent
to the higher CNS regarding the perception of bitter/irritating chemical
stimuli.
相似文献
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