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31.
32.
Robert F.H. Dekker Ana-Flora D. Vasconcelos Aneli M. Barbosa Ellen C. Giese Luzia Paccola-Meirelles 《Biotechnology letters》2001,23(24):1987-1993
A new physiological role for veratryl alcohol in fungi important in the biodegradation of the lignified plant cell wall is presented. Botryosphaeria sp., grown on starch, pectin, cellulose or xylan produced amylase, pectinase, cellulase, xylanase and laccase, whereas glucose and xylose repressed the synthesis of cellulase and xylanase, but not laccase. When cultured on each of these substrates in the presence of veratryl alcohol, laccase activity increased but the activities of amylase, pectinase, cellulase and xylanase significantly decreased. Basal medium containing softwood kraft lignin in the presence of veratryl alcohol induced laccases above constitutive levels. Ethyl alcohol also stimulated laccase production. 相似文献
33.
Maria Fernanda Forni Aline Ramos Maia Lobba Alexandre Hamilton Pereira Ferreira Mari Cleide Sogayar 《PloS one》2015,10(10)
The skin is a rich source of readily accessible stem cells. The level of plasticity afforded by these cells is becoming increasingly important as the potential of stem cells in Cell Therapy and Regenerative Medicine continues to be explored. Several protocols described single type stem cell isolation from skin; however, none of them afforded simultaneous isolation of more than one population. Herein, we describe the simultaneous isolation and characterization of three stem cell populations from the dermis and epidermis of murine skin, namely Epidermal Stem Cells (EpiSCs), Skin-derived Precursors (SKPs) and Mesenchymal Stem Cells (MSCs). The simultaneous isolation was possible through a simple protocol based on culture selection techniques. These cell populations are shown to be capable of generating chondrocytes, adipocytes, osteocytes, terminally differentiated keratinocytes, neurons and glia, rendering this protocol suitable for the isolation of cells for tissue replenishment and cell based therapies. The advantages of this procedure are far-reaching since the skin is not only the largest organ in the body, but also provides an easily accessible source of stem cells for autologous graft. 相似文献
34.
Alfredo Brusco Fernanda Cinque Silvia Saviozzi Cleide Boccazzi Mario DeMarchi A. O. Carbonara 《Human genetics》1997,100(1):84-89
The structure of the human immunoglobulin heavy chain constant region (IGHC), on chromosome 14q32, comprises nine CH genes
and two pseudogenes, all originating from multiple duplication events. Continuing evolution of the region is demonstrated
by the finding of various types of duplicated and deleted haplotypes, which together add up to 6%. Here we provide molecular
and genetic evidence that the G4 gene is duplicated in 44% of IGHC haplotypes in the Italian population. The duplication spans
about 20 kb of genomic DNA and probably originated through unequal crossing over. Refined characterisation of the genomic
region downstream from the G4 gene improves our knowledge of the evolutionary history of CH genes.
Received: 4 December 1996 / Accepted: 10 February 1997 相似文献
35.
36.
Pablo?Ramon?Gualberto?Cardoso Emerson?Vasconcelos?de?Andrade Lima Mariana?Modesto?de?Andrade Lima Moacyr?Jesus?Barreto?de?Melo Rêgo Claudia?Diniz?Lopes?Marques Ivan?da?Rocha Pitta Angela?Luzia?Branco?Pinto?Duarte Maira?Galdino?da?Rocha PittaEmail author 《European cytokine network》2016,27(1):1-5
Objective and Design
Psoriasis is a common, enigmatic, and recurrent disease. The precise etiology and pathogenesis of psoriasis are still unclear. Psoriasis has been treated as an inflammatory disorder related to an underlying Th1/Th17-dominated immune response. Interleukins are involved in the development of psoriasis lesions through Th-17-associated inflammation. Th1 and Th17 cytokines are found in skin lesions and in the peripheral blood of psoriasis patients.We sought to analyze serum levels of IL-1-β, IL-8, IL-9, IL-27, IL-29, IL-35, IFN-γ, TNF and TGF-β in patients with psoriasis and healthy control volunteers.Material
Blood samples were collected from fifty-three patients with psoriasis and thirty-five healthy controls.Methods
Serum cytokines concentrations were determined using an enzyme-linked immunosorbent assay.Results
Serum IL-8, IL-9, IL-27, IL-29 and TNF levels were statistically significant in psoriasis patients. Detectable serum IL-9 levels were found in 47 patients of the 53 in the psoriasis group.Conclusions
Interleukins-8, 27, 29 and TNF levels measured in the serum of psoriasis patients were slightly elevated as compared to healthy controls in a weakly significant way. On the other hand, there were highly significant differences in IL-9 levels between the two groups.37.
Natalia N. Ninkina Eugenia M. Privalova Luzia G. P. Pinn Alun M. Davies Vladimir L. Buchman 《Experimental cell research》1999,246(2):308
Synucleins constitute a group of unique, evolutionarily conserved proteins that are expressed predominantly in neurons of the central and peripheral nervous system. Although the normal cellular functions of synucleins are not clear, these proteins have been implicated in various neurodegenerative conditions in humans. We found that persyn, a recently characterized member of the synuclein family, is expressed not only in the nervous system but also in the stratum granulosum of the epidermis of neonatal and adult mice. This finding together with our recent observations that persyn influences neurofilament network integrity in sensory neurons raises the possibility that persyn in skin could be involved in modulation of the keratin network. 相似文献
38.
Environmental and spatial processes influencing phytoplankton biomass along a reservoirs‐river‐floodplain lakes gradient: A metacommunity approach
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Jascieli Carla Bortolini Alfonso Pineda Luzia Cleide Rodrigues Susicley Jati Luiz Felipe Machado Velho 《Freshwater Biology》2017,62(10):1756-1767
39.
Alkmim Aline R. da Costa Paula R. Moser Priscila B. Neta Luzia S. França Santiago Vânia M. J. Cerqueira Ana. C. Reis Beatriz G. Amaral Míriam C. S. 《Bioprocess and biosystems engineering》2017,40(12):1839-1850
Bioprocess and Biosystems Engineering - This study aims to evaluate membrane bioreactor (MBR) performance in a pilot scale to treat petroleum refinery effluent, and has been primarily focused on... 相似文献
40.
Eberhardt BG Satrapa RA Capinzaiki CR Trinca LA Barros CM 《Animal reproduction science》2009,114(1-3):54-61
In vitro studies have shown that Bos taurus indicus (B. t. indicus) embryos submitted to heat shock at early stages of development are better able to survive as compared to Bos taurus taurus embryos. Embryo genotype influences resistance to heat shock thus leading to the question as to whether embryos sired by thermo-tolerant breeds exhibit the same resistance to heat shock. In the present study the influence of both oocyte and semen, on the resistance to heat shock (HS) at early stages of in vitro development, was assessed in B. t. indicus [Nelore (N) breed], B. t. taurus [Holstein (H) and Angus (A) breeds] and crossbreds. In Experiment 1, Nelore and crossbred oocytes were collected from slaughterhouse ovaries and fertilized with spermatozoa from Nelore and Angus bulls. Presumptive embryos were collected and randomly assigned to control (39 degrees C) or HS at 12, 48 or 96 h post insemination (hpi; 41 degrees C for 12h) treatments. The cleavage rates and proportion of embryos developing to the blastocyst and hatched blastocyst stages were recorded on Days 2, 8 and 10, respectively. Heat shock treatment decreased development of both Nelore and crossbred embryos. There was a significant interaction between time (12, 48 or 96 hpi) and temperature for blastocyst rates, i.e., the embryos became more thermotolerant as development proceeded. In Experiment 2, oocytes from Nelore and Holstein cows were fertilized with semen from bulls of either Nelore or Angus breeds, and subjected to 12 h HS at 96 hpi. Heat shock at 96 hpi, decreased embryo development. Additionally, cowxtreatment and bullxtreatment interactions were significant for blastocyst rates, i.e., both breed of cow and breed of bull affected the decline in blastocyst rate caused by heat shock treatment. In conclusion, the present results indicate that Nelore embryos (indicus) are more resistant to heat shock than Holstein (taurus) at early stages of in vitro development, and that embryos become more thermo-tolerant as development proceeds. Additionally, the resistance to heat shock was a result of the genetic contribution from both oocyte and spermatozoa. 相似文献