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121.
Jonny E. Scherwinski-Pereira Elequisandra da C. Araruna Lima Tatiane L. da Silva Antonio G. Gomes Mesquita Simone de A. Maciel Frederico H. da Silva Costa 《Plant Cell, Tissue and Organ Culture》2012,109(2):263-269
We have developed an efficient and simplified method for shoot proliferation of the pineapple (Ananas comosus L.), using a Double-Phase Culture System (DPS) (semi-solid medium with a layer of liquid medium on the top). Under these
conditions, up to 430 microshoots were produced from 5 initial shoots within 5 months, and without shoot manipulation. Thus,
>50% shoots proliferated as compared to that on agar-solidified medium. Shoots taken from DPS were rooted within 4 weeks at
a frequency of up to 100%, in full-strength or half-strength Murashige and Skoog medium containing 0.5–2.5 μM indole-3-butyric
acid. The plantlets were then transferred into soil, and they survived acclimatization with 100% success. Thus, DPS could
be useful for large-scale micropropagation of a range of pineapple cultivars, with high production of plantlets at the end
of process, and reduced labor costs during the subcultures. 相似文献
122.
I.C. Macedo L.F. Medeiros C. Oliveira C.M. Oliveira J.R. Rozisky V.L. Scarabelot A. Souza F.R. Silva V.S. Santos S.G. Cioato W. Caumo I.L.S. Torres 《Peptides》2012
Obesity is a disease that has become a serious public health issue worldwide, and chronic stressors, which are a problem for modern society, cause neuroendocrine changes with alterations in food intake. Obesity and chronic stress are associated with the development of cardiovascular diseases and metabolic disorders. In this study, a rat model was used to evaluate the effects of a hypercaloric diet plus chronic restraint stress on the serum leptin and lipids levels and on the weight of specific adipose tissue (mesenteric, MAT; subcutaneous, SAT and visceral, VAT). Wistar rats were divided into the following 4 groups: standard chow (C), hypercaloric diet (HD), stress plus standard chow (S), and stress plus hypercaloric diet (SHD). The animals in the stress groups were subjected to chronic stress (placed inside a 25 cm × 7 cm plastic tube for 1 h per day, 5 days per week for 6 weeks). The following parameters were evaluated: the weight of the liver, adrenal glands and specific adipose tissue; the delta weight; the Lee index; and the serum levels of leptin, corticosterone, glucose, total cholesterol, and triglycerides. The hypercaloric diet induced obesity in rats, increasing the Lee index, weight, leptin, triglycerides, and cholesterol levels. The stress decreased weight gain even in animals fed a hypercaloric diet but did not prevent a significant increase in the Lee index. However, an interaction between the independent factors (hypercaloric diet and stress) was observed, which is demonstrated by the increased serum leptin levels in the animals exposed to both protocols. 相似文献
123.
Draulio C. SilvaAna Lucia P. Freitas Francisco Clark N. BarrosKézia O.A.L. Lins Ana Paula N.N. AlvesNylane M.N. Alencar Ingrid S.T. de FigueiredoCláudia Pessoa Manoel O. de MoraesLetícia V. Costa-Lotufo Judith P.A. FeitosaJeanny S. Maciel Regina C.M. de Paula 《Carbohydrate polymers》2012,87(1):139-145
A hot water-extracted polysaccharide fraction (PFCM) of Passiflora edulis was characterized by microanalysis, infrared spectroscopy, NMR and high performance size-exclusion chromatography. The major component in PFCM is (1 → 4) linked galacturonic acid (esterified and unesterified). Neutral sugars such as arabinose, glucose, rhamnose, mannose, and fucose were also present. Traces of xylose and ribose were detected. The PFCM sample had a similar molar mass to that of pectin extracted from P. edulis under acidic conditions. Sarcoma 180 tumors treated with PFCM showed a growth inhibition ratio ranging from 40.59% to 48.73% depending on the dosage and type of PFCM administration (oral or intraperitoneal). Toxicological analysis shows that PFCM increases the cell types involved in primary defense mechanisms and no significant changes in the biochemical parameters and organs (e.g., kidney and liver) were observed. However, the use of PFCM treatment increased the spleen weight when compared with the use of 5-fluorouracil. 相似文献
124.
Dias MO Junqueira TL Cavalett O Cunha MP Jesus CD Rossell CE Maciel Filho R Bonomi A 《Bioresource technology》2012,103(1):152-161
Ethanol production from lignocellulosic materials is often conceived considering independent, stand-alone production plants; in the Brazilian scenario, where part of the potential feedstock (sugarcane bagasse) for second generation ethanol production is already available at conventional first generation production plants, an integrated first and second generation production process seems to be the most obvious option. In this study stand-alone second generation ethanol production from surplus sugarcane bagasse and trash is compared with conventional first generation ethanol production from sugarcane and with integrated first and second generation; simulations were developed to represent the different technological scenarios, which provided data for economic and environmental analysis. Results show that the integrated first and second generation ethanol production process from sugarcane leads to better economic results when compared with the stand-alone plant, especially when advanced hydrolysis technologies and pentoses fermentation are included. 相似文献
125.
Ferreira SM Domingos GP Ferreira Ddos S Rocha TG Serakides R de Faria Rezende CM Cardoso VN Fernandes SO Oliveira MC 《Bioorganic & medicinal chemistry letters》2012,22(14):4605-4608
Osteomyelitis is an infectious disease located in the bone or bone marrow. Long-circulating and pH-sensitive liposomes containing a technetium-99m-labeled antibiotic, ceftizoxime, (SpHL-(99m)Tc-CF) were developed to identify osteomyelitis foci. Biodistribution studies and scintigraphic images of bone infection or non infection-bearing rats that had been treated with these liposomes were performed. A high accumulation in infectious foci and high values in the target-non target ratio could be observed. These results indicate the potential of SpHL-(99m)Tc-CF as a potential agent for the diagnosis of bone infections. 相似文献
126.
127.
de Medeiros Modolon S Otsuka I Fort S Minatti E Borsali R Halila S 《Biomacromolecules》2012,13(4):1129-1135
The preparation of biocompatible nanocarriers that have potential applications in the cosmetic and health industries is highly desired. The self-assembly of amphiphilic block copolymers displaying biosourced polysaccharides at the surface is one of the most promising approaches. In the continuity of our works related to the preparation of "hybrid" amphiphilic oligosaccharide-based block copolymers, we present here the design of a new generation of self-assembled nanoparticles composed entirely of oligosaccharide-based amphiphilic block co-oligomers (BCO). These systems are defined by a covalent linkage of the two saccharidic blocks through their reducing end units, resulting in a sweet "head-to-head" connection. As an example, we have prepared and studied a BCO in which the hydrophilic part is composed of a free maltoheptaosyl derivative clicked to a hydrophobic part composed of a peracetylated maltoheptaosyl derivative. This amphiphilic BCO self-assembles to form spherical micelles in water with an average diameter of 30 nm. The efficient enzymatic hydrolysis of the maltoheptaose that constitutes the shell of the micelles was followed by light scattering and colorimetric methods. 相似文献
128.
Montano MA da Cruz IB Duarte MM da Costa Krewer C de Ugalde Marques da Rocha MI Mânica-Cattani MF Soares FA Rosa G Maris AF Battiston FG Trott A Lera JP 《Cytokine》2012,60(1):30-33
Obesity is considered a chronic low-grade inflammatory state associated with a chronic oxidative stress caused by superoxide production (O(2)(-)). The superoxide dismutase manganese dependent (SOD2) catalyzes O(2)(-) in H(2)O(2) into mitochondria and is encoded by a single gene that presents a common polymorphism that results in the replacement of alanine (A) with a valine (V) in the 16 codon. This polymorphism has been implicated in a decreased efficiency of SOD2 transport into targeted mitochondria in V allele carriers. Previous studies described an association between VV genotype and metabolic diseases, including obesity and diabetes. However, the causal mechanisms to explain this association need to be more elucidated. We postulated that the polymorphism could influence the inflammatory response. To test our hypothesis, we evaluated the in vitro cytokines production by human peripheral blood mononuclear cells (PBMCs) carrier's different Ala16Val-SOD2 genotypes (IL-1, IL-6, IL-10, TNF-α, IFN-γ). Additionally, we evaluated if the culture medium glucose, enriched insulin, could influence the cytokine production. Higher levels of proinflammatory cytokines were observed in VV-PBMCs when compared to AA-PBMCs. However, the culture medium glucose and enriched insulin did not affect cytokine production. The results suggest that Ala16Val-SOD2 gene polymorphism could trigger the PBMCs proinflammatory cytokines level. However, discerning if a similar mechanism occurs in fat cells is an open question. 相似文献
129.
130.
Ectoparasites, particularly chewing lice in the Phthiraptera (Insecta), affect the ecology of numerous host species. Most lice are highly host-specific, and there are no documented cases of major increases of chewing lice, within populations, over years. During continuous study from 1987-2005 at upper elevation forests on the island of Hawaii, chewing lice were exceedingly rare and, until 2003, were found in just 2 of 12 species of native and introduced birds. From 2003-2005, there was an explosive increase in the prevalence of chewing lice in all host species. There was no change in humidity, or in behavior of hosts, that could have caused an ecological release of existing lice. Based on reduced fat levels and increases in broken wing and tail feathers for most host species, there was apparently a food limitation that preceded the increase. The increase coincided temporally with detection of a nonnative bird that had recently been found in elevations below the study sites. Although there were isolated sightings of this bird on the study sites, seasonal movements and behavior of some species of native birds could also have allowed greater transmission to study sites. Both prevalence and intensity of infection, indexed by number of body regions parasitized, were lower in native species with greater bill overlap, a character that could help birds control lice. Seasonality of prevalence indicated that low prevalence preceded molt and high prevalence occurred after molting of hosts. The number of major fault bars in wing and tail feathers, a sign of nutritive stress, was correlated with intensity of infection, indicating an indirect cost to the hosts of being parasitized. In addition, birds with lice were less likely to be recaptured than birds without lice. 相似文献