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91.

Background

Nerve transfers are commonly employed in the treatment of brachial plexus injuries. We report the use of a new donor for transfer, the platysma motor branch.

Methods

A patient with complete avulsion of the brachial plexus and phrenic nerve paralysis had the suprascapular nerve neurotized by the accessory nerve, half of the hypoglossal nerve transferred to the musculocutaneous nerve, and the platysma motor branch connected to the medial pectoral nerve.

Results

The diameter of both the platysma motor branch and the medial pectoral nerve was around 2 mm. Eight years after surgery, the patient recovered 45° of abduction. Elbow flexion and shoulder adduction were rated as M4, according to the BMC. There was no deficit after the use of the above-mentioned nerves for transfer. Volitional control was acquired for independent function of elbow flexion and shoulder adduction.

Conclusion

The use of the platysma motor branch seems promising. This nerve is expendable; its section led to no deficits, and the relearning of motor control was not complicated. Further anatomical and clinical studies would help to clarify and confirm the usefulness of the platysma motor branch as a donor for nerve transfer.  相似文献   
92.
Integration of biological networks and gene expression data using Cytoscape   总被引:1,自引:0,他引:1  
Cytoscape is a free software package for visualizing, modeling and analyzing molecular and genetic interaction networks. This protocol explains how to use Cytoscape to analyze the results of mRNA expression profiling, and other functional genomics and proteomics experiments, in the context of an interaction network obtained for genes of interest. Five major steps are described: (i) obtaining a gene or protein network, (ii) displaying the network using layout algorithms, (iii) integrating with gene expression and other functional attributes, (iv) identifying putative complexes and functional modules and (v) identifying enriched Gene Ontology annotations in the network. These steps provide a broad sample of the types of analyses performed by Cytoscape.  相似文献   
93.
Innovations are central for the economic growth; however, the use of new technologies needs to be widely accepted in the general public and the society as a whole. Biotechnology in general, and the use of genetic engineering in food production in particular are seen critically by the European public and perceived as "risky", and a transatlantic divide between European and US citizens has been observed. This review investigates the reasons for those differing perceptions and proposes new strategies to communicate the benefits of biotechnology in agriculture to a broader public. When analyzing the dialogue process that has taken place between public, scientists, governmental organizations and industry, questions arise on what has been done differently in Europe, in order to propose new, more successful and efficient communication strategies for the future.  相似文献   
94.
The effect of minocycline on nerve regeneration was studied in a rat model of acute sciatic nerve injury, in which the injury was caused by resection and reimplantation of the right sciatic nerve. Immunohistochemical and molecular biological methods, as well as morphometric and electron microscopic techniques, were used. Compared with uninjured and PBS-treated injured nerves, the minocycline-treated injured nerve showed: (i) a decrease in macrophage recruitment and activation, probably resulting from inhibition of blood-brain-barrier break-down via reduced MMP2 and MMP9 induction, inhibition of revascularization via additional reduction of VEGF induction, and inhibition of inducible NO synthase (iNOS) induction; (ii) reduced activation of phagocytic Schwann cells, probably by inhibition of iNOS, MMP2 and MMP9 expression; (iii) a slowed Wallerian degeneration; and subsequently, (iv) a diminished nerve regeneration. Macrophages, especially their function in the removal of cellular debris and formation of a microenvironment beneficial for nerve regeneration, are strongly implicated in constructive events after nerve injuries. Therefore, we suggest that additional research into optimizing minocycline intervention for treatment of neurodegenerative diseases is needed before further clinical trials are performed.  相似文献   
95.
The timing of sexual maturation in non-avian dinosaurs is not known. In extant squamates and crocodilians it occurs in conjunction with the initial slowing of growth rates as adult size is approached. In birds (living dinosaurs) on the other hand, reproductive activity begins well after somatic maturity. Here we used growth line counts and spacing in all of the known brooding non-avian dinosaurs to determine the stages of development when they perished. It was revealed that sexual maturation occurred well before full adult size was reached-the primitive reptilian condition. In this sense, the life history and physiology of non-avian dinosaurs was not like that of modern birds. Palaeobiological ramifications of these findings include the potential to deduce reproductive lifespan, fecundity and reproductive population sizes in non-avian dinosaurs, as well as aid in the identification of secondary sexual characteristics.  相似文献   
96.
Dimethylamine [DMA, (CH(3))(2)NH)] is abundantly present in human urine. Main sources of urinary DMA have been reported to include trimethylamine N-oxide, a common food component, and asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide (NO) synthesis. ADMA is excreted in the urine in part unmetabolized and in part after hydrolysis to DMA by dimethylarginine dimethylaminohydrolase (DDAH). Here we describe a GC-MS method for the accurate and rapid quantification of DMA in human urine. The method involves use of (CD(3))(2)NH as internal standard, simultaneous derivatization with pentafluorobenzoyl chloride and extraction in toluene, and selected-ion monitoring of m/z 239 for DMA and m/z 245 for (CD(3))(2)NH in the electron ionization mode. GC-MS analysis of urine samples from 10 healthy volunteers revealed a DMA concentration of 264+/-173 microM equivalent to 10.1+/-1.64 micromol/mmol creatinine. GC-tandem MS analysis of the same urine samples revealed an ADMA concentration of 27.3+/-15.3 microM corresponding to 1.35+/-1.2 micromol/mmol creatinine. In these volunteers, a positive correlation (R=0.83919, P=0.0024) was found between urinary DMA and ADMA, with the DMA/ADMA molar ratio being 10.8+/-6.2. Elevated excretion rates of DMA (52.9+/-18.5 micromol/mmol creatinine) and ADMA (3.85+/-1.65 micromol/mmol creatinine) were found by the method in 49 patients suffering from coronary artery disease, with the DMA/ADMA molar ratio also being elevated (16.8+/-12.8). In 12 patients suffering from end-stage liver disease, excretion rates of DMA (47.8+/-19.7 micromol/mmol creatinine) and ADMA (5.6+/-1.5 micromol/mmol creatinine) were found to be elevated, with the DMA/ADMA molar ratio (9.17+/-4.2) being insignificantly lower (P=0.46). Between urinary DMA and ADMA there was a positive correlation (R=0.6655, P<0.0001) in coronary artery disease, but no correlation (R=0.27339) was found in end-stage liver disease.  相似文献   
97.
iTRAQ compatibility of peptide immobilized pH gradient isoelectric focusing   总被引:9,自引:0,他引:9  
Lengqvist J  Uhlén K  Lehtiö J 《Proteomics》2007,7(11):1746-1752
Immobilized pH gradient isoelectric focusing (IPG-IEF) has emerged as a highly promising alternative to strong-cation exchange fractionation as the first dimension in shot-gun proteomics. Herein is shown the compatibility of this method with iTRAQ isotope labeling for relative quantitation and validation of sequence matches from database searching.  相似文献   
98.
We have previously identified and characterized two novel nuclear RNA binding proteins, p34 and p37, which have been shown to bind 5S rRNA in Trypanosoma brucei. These two proteins are nearly identical, with one major difference, an 18-amino-acid insert in the N-terminal region of p37, as well as three minor single-amino-acid differences. Homologues to p34 and p37 have been found only in other trypanosomatids, suggesting that these proteins are unique to this ancient family. We have employed RNA interference (RNAi) studies in order to gain further insight into the interaction between p34 and p37 with 5S rRNA in T. brucei. In our p34/p37 RNAi cells, decreased expression of the p34 and p37 proteins led to morphological alterations, including loss of cell shape and vacuolation, as well as to growth arrest and ultimately to cell death. Disruption of a higher-molecular-weight complex containing 5S rRNA occurs as well as a dramatic decrease in 5S rRNA levels, suggesting that p34 and p37 serve to stabilize 5S rRNA. In addition, an accumulation of 60S ribosomal subunits was observed, accompanied by a significant decrease in overall protein synthesis within p34/p37 RNAi cells. Thus, the loss of the trypanosomatid-specific proteins p34 and p37 correlates with a diminution in 5S rRNA levels as well as a decrease in ribosome activity and an alteration in ribosome biogenesis.  相似文献   
99.
Arthropod crop pests are responsible for 20% of global annual crop losses, a figure predicted to increase in a changing climate where the ranges of numerous species are projected to expand. At the same time, many insect species are beneficial, acting as pollinators and predators of pest species. For thousands of years, humans have used increasingly sophisticated chemical formulations to control insect pests but, as the scale of agriculture expanded to meet the needs of the global population, concerns about the negative impacts of agricultural practices on biodiversity have grown. While biological solutions, such as biological control agents and pheromones, have previously had relatively minor roles in pest management, biotechnology has opened the door to numerous new approaches for controlling insect pests. In this review, we look at how advances in synthetic biology and biotechnology are providing new options for pest control. We discuss emerging technologies for engineering resistant crops and insect populations and examine advances in biomanufacturing that are enabling the production of new products for pest control.  相似文献   
100.
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