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991.
JoséFábio Santos Duarte Lana Lucas Furtado da Fonseca Rafael da Rocha Macedo Tomas Mosaner William Murrell Ashok Kumar Joseph Purita Marco Antonio Percope de Andrade 《World journal of stem cells》2021,13(2):155-167
The use of orthobiologics as a novel therapy for the treatment of numerous musculoskeletal disorders has increased considerably over the past decade.Currently,there are multiple alternatives available as suitable treatments;however,the use of autologous blood-derived products such as platelet-rich plasma(PRP),bone marrow aspirate(BMA)and BMA concentrate(BMAC),specifically,is expanding.Although many investigations attempted to demonstrate the effectiveness of these therapies,even with positive results,the literature lacks standardized protocols and overall accuracy in study designs,which leads to variance and difficulty in reproducibility of protocols.The efficacy of PRP for the treatment of cartilage,bone and muscle tissues is well known.Although BMAC has generated optimistic results for the same purposes,its applicability in clinical trials is still relatively recent when compared to PRP.Both products demonstrate the potential to set forth reparative processes,each in their own distinct mechanism.The combination of these biological products has been previously proposed,yet little is known about their synergism.Evidence indicates that growth factor,cytokine,and chemokine profiles seen in both PRP and BMAC vary but are likely to work synergistically to enhance musculoskeletal healing.BMAC products seem to work well without PRP;however,the addition of PRP to BMAC has been shown to act as a rich and natural source of culture medium for stem cells located either peripherally or in the bone marrow itself.Nevertheless,additional variables associated with the use of BMAC and PRP in orthopedics must be further evaluated in order to consolidate the efficacy of this therapeutic strategy. 相似文献
992.
Jeffry I. Fasick Nicole Bischoff Stephanie Brennan Stephani Velasquez Gisele Andrade 《Marine Mammal Science》2011,27(4):E321-E331
To assess the spectral sensitivities of the retinal visual pigments from the North Atlantic right whale (Eubalaena glacialis), we have cloned and sequenced two exons from the rod opsin gene and two exons from the middle‐wavelength sensitive (MWS) cone opsin gene in order to determine the amino acids at positions known to be key regulators of the spectral location of the absorbance maximum (λmax). Based on previous mutagenesis models we estimate that the right whale possesses a rod visual pigment with a λmax of 499 nm and a MWS cone visual pigment with a λmax of 524 nm. Although the MWS cone visual pigment from the right whale is blue‐shifted in its spectral sensitivity like those from odontocetes, the spectral sensitivity of the right whale rod visual pigment is similar to those from terrestrial mammals. 相似文献
993.
Aline Finger Teixeira Aneliz de Bastos Andrade Osvaldo Ferrarese-Filho Maria de Lourdes Lucio Ferrarese 《Plant Growth Regulation》2006,49(1):69-76
Changes in soluble and cell wall bound peroxidases activities, phenylalanine ammonia-lyase activity and phenolic compounds
and lignin contents in roots of calcium-treated soybean (Glycine max (L.) Merr.) seedlings and their relationships with root growth were investigated. Three-day-old soybean seedlings were cultivated
in nutrient solution with or without 0.025–5.0 mM calcium for 24 h. In general, length and fresh and dry weights of roots
increased, while activities of enzymes (soluble and cell-wall peroxidases and phenylalanine ammonia-lyase) and phenolic compounds
and lignin contents decreased against calcium concentrations. In the absence of calcium, phenylalanine ammonia-lyase and peroxidases
activities increased by accumulating phenolic compounds and lignin due to restricted growth of roots. Enhanced calcium supply
reduced the production of phenolic compounds and lignification due to low phenylalanine ammonia-lyase and peroxidases activities,
reinforcing the essential role of calcium to improve the soybean root growth. 相似文献
994.
The transient existence of small RNAs free of binding to the RNA chaperone Hfq is part of the normal dynamic lifecycle of a sRNA. Small RNAs are extremely labile when not associated with Hfq, but the mechanism by which Hfq stabilizes sRNAs has been elusive. In this work we have found that polynucleotide phosphorylase (PNPase) is the major factor involved in the rapid degradation of small RNAs, especially those that are free of binding to Hfq. The levels of MicA, GlmY, RyhB, and SgrS RNAs are drastically increased upon PNPase inactivation in Hfq(-) cells. In the absence of Hfq, all sRNAs are slightly shorter than their full-length species as result of 3'-end trimming. We show that the turnover of Hfq-free small RNAs is growth-phase regulated, and that PNPase activity is particularly important in stationary phase. Indeed, PNPase makes a greater contribution than RNase E, which is commonly believed to be the main enzyme in the decay of small RNAs. Lack of poly(A) polymerase I (PAP I) is also found to affect the rapid degradation of Hfq-free small RNAs, although to a lesser extent. Our data also suggest that when the sRNA is not associated with Hfq, the degradation occurs mainly in a target-independent pathway in which RNase III has a reduced impact. This work demonstrated that small RNAs free of Hfq binding are preferably degraded by PNPase. Overall, our data highlight the impact of 3'-exonucleolytic RNA decay pathways and re-evaluates the degradation mechanisms of Hfq-free small RNAs. 相似文献
995.
Heverton Leandro Carneiro Dutra Lilha Maria Barbosa dos Santos Eric Pearce Caragata Jéssica Barreto Lopes Silva Daniel Antunes Maciel Villela Rafael Maciel-de-Freitas Luciano Andrade Moreira 《PLoS neglected tropical diseases》2015,9(4)
Background
The symbiotic bacterium Wolbachia is currently being trialled as a biocontrol agent in several countries to reduce dengue transmission. Wolbachia can invade and spread to infect all individuals within wild mosquito populations, but requires a high rate of maternal transmission, strong cytoplasmic incompatibility and low fitness costs in the host in order to do so. Additionally, extensive differences in climate, field-release protocols, urbanization level and human density amongst the sites where this bacterium has been deployed have limited comparison and analysis of Wolbachia’s invasive potential.Methodology/Principal Findings
We examined key phenotypic effects of the wMel Wolbachia strain in laboratory Aedes aegypti mosquitoes with a Brazilian genetic background to characterize its invasive potential. We show that the wMel strain causes strong cytoplasmic incompatibility, a high rate of maternal transmission and has no evident detrimental effect on host fecundity or fertility. Next, to understand the effects of different urban landscapes on the likelihood of mosquito survival, we performed mark-release-recapture experiments using Wolbachia-uninfected Brazilian mosquitoes in two areas of Rio de Janeiro where Wolbachia will be deployed in the future. We characterized the mosquito populations in relation to the socio-demographic conditions at these sites, and at three other future release areas. We then constructed mathematical models using both the laboratory and field data, and used these to describe the influence of urban environmental conditions on the likelihood that the Wolbachia infection frequency could reach 100% following mosquito release. We predict successful invasion at all five field sites, however the conditions by which this occurs vary greatly between sites, and are strongly influenced by the size of the local mosquito population.Conclusions/Significance
Through analysis of laboratory, field and mathematical data, we show that the wMel strain of Wolbachia possesses the characteristics required to spread effectively in different urban socio-demographic environments in Rio de Janeiro, including those where mosquito releases from the Eliminate Dengue Program will take place. 相似文献996.
The flavonoid pattern of larvae of cabbage white butterfly (Pieris brassicae L.; Lepidoptera: Pieridae) reared on the leaves of tronchuda cabbage was analysed by HPLC-DAD-MS/MS-ESI. Twenty flavonoids were identified or characterised, namely 16 kaempferol and four quercetin derivatives. Kaempferol 3-O-sophoroside, a minor component of tronchuda cabbage, was found to be the main component in P. brassicae (15.8%). Apart from this, only two other flavonoids present in significant amounts in tronchuda cabbage (kaempferol 3-O-sophoroside-7-O-glucoside and kaempferol 3-O-sophoroside-7-O-sophoroside) were found in the larvae. The larvae have high amounts of quercetin derivatives (18.5%), which were present only in trace amounts in tronchuda cabbage extracts, suggesting that P. brassicae is able to selectively sequester these flavonoids. The occurrence of a high content of flavonoids not detectable in tronchuda cabbage extracts indicates that P. brassicae larvae are able to metabolize dietary flavonoids. 相似文献
997.
L.U. Guedes V.F. Parreira A.C.M. Diório F. Goulart A.D. Andrade R.R. Britto 《Journal of electromyography and kinesiology》2009,19(4):591-597
The aim of this study was to evaluate the effect of administration of levo–dopa, which means without effect-off state and under effect-on state, on the sternocleidomastoid muscle electromyographic activity (SCM-EA) in patients with Parkinson’s disease (PD) at rest and to compare it to asymptomatic subjects. Ten patients with PD, mean age 64.6 ± 6.2 (SD) years and nine asymptomatic subjects, mean age 61.4 ± 5.9 (SD) years were studied. The SCM-EA was evaluated during maximal inspiratory pressure and breathing at rest through surface electromyography. Statistical analysis was performed with t-test (anthropometric data and SCM-EA of patients in off state to asymptomatic), Mann–Whitney (SCM-EA of patients in on state to asymptomatic) and Wilcoxon test (SCM-EA off and on states). The effect size index (d) was calculated for statistically significant differences. There were no significant differences in SCM electromyographic activity between patients with PD comparing off to on (p = 0.13) or among on state to asymptomatic subjects (p = 0.06). However, when subjects with PD in off where compared to asymptomatic there was a significantly higher SCM electromyographic activity (p = 0.03, d = 1.09). These patients, without levo–dopa effect, when compared with asymptomatic subjects, present a significantly higher electromyographic activity of SCM, the main accessory respiratory muscle, which could be related to an increased work of breathing. 相似文献
998.
Gopal Sirasani Tapas Paul Rodrigo B. Andrade 《Bioorganic & medicinal chemistry》2010,18(11):3648-3655
Two approaches toward the total synthesis of cytotoxic polyketide natural product (+)-crocacin C (1) are described. The first approach, which was ultimately unsuccessful, was replaced altogether with a second that afforded target 1 in 10 linear steps from commercially available Evans’ chiral propionimide (5% overall yield). No protecting groups were utilized in the total synthesis of 1. 相似文献
999.
Rodrigo Cappato de Araújo Helga Tatiana Tucci Rodrigo de Andrade Jaqueline Martins Débora Bevilaqua-Grossi Anamaria Siriani de Oliveira 《Journal of electromyography and kinesiology》2009,19(4):685-694
The purpose of the present study was to evaluate the intra and interday reliability of surface electromyographic amplitude values of the scapular girdle muscles and upper limbs during 3 isometric closed kinetic chain exercises, involving upper limbs with the fixed distal segment extremity on stable base of support and on a Swiss ball (relatively unstable). Twenty healthy adults performed the exercises push-up, bench-press and wall-press with different effort levels (80% and 100% maximal load). Subjects performed three maximal voluntary contractions (MVC) in muscular testing position of each muscle to obtain a reference value for root mean square (RMS) normalization. Individuals were instructed to randomly perform three isometric contraction series, in which each exercise lasted 6 s with a 2-min resting-period between series and exercises. Intra and interday reliabilities were calculated through the intraclass correlation coefficient (ICC 2.1), standard error of the measurement (SEM). Results indicated an excellent intraday reliability of electromyographic amplitude values (ICC ? 0.75). The interday reliability of normalized RMS values ranged between good and excellent (ICC 0.52–0.98). Finally, it is suggested that the reliability of normalized electromyographic amplitude values of the analyzed muscles present better values during exercises on a stable surface. However, load levels used during the exercises do not seem to have any influence on variability levels, possibly because the loads were quite similar. 相似文献
1000.
Behavioural patterns of sea lampreys' spawning migration through difficult passage areas, studied by electromyogram telemetry 总被引:2,自引:0,他引:2
Electromyogram telemetry (EMG) was used to study the behaviour of sea lamprey Petromyzon marinus during migration through difficult passage areas. When swimming on stretches free from obstacles, the EMG values of sea lampreys showed a constant pattern of activity. Conversely, when negotiating difficult passage areas their behaviour were characterized by alternating between short bursts of intense activity ( i.e . burst movements) and periods of motionless rest during which sea lampreys attached to convenient structures by means of the oral sucker. During blockstone weirs negotiation, tagged sea lampreys spent on average 23% of the time swimming rapidly by means of multiple bouts of burst movements of 31 s duration. To recover from each burst movement, the sea lampreys spent on average 2 min 25 s resting. Sea lampreys seemed affected by increasing fatigue, which probably resulted from initiating a new burst movement without fully recovering physiologically from the previous efforts. 相似文献