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71.
MG Mullender NA Blom M De Kleuver JM Fock WMGC Hitters AMC Horemans CJ Kalkman JEH Pruijs RR Timmer PJ Titarsolej NC Van Haasteren Tol-de MJ Van Jager AJ Van Vught BJ Van Royen 《Scoliosis》2008,3(1):1-14
Background
Children with neuromuscular disorders with a progressive muscle weakness such as Duchenne Muscular Dystrophy and Spinal Muscular Atrophy frequently develop a progressive scoliosis. A severe scoliosis compromises respiratory function and makes sitting more difficult. Spinal surgery is considered the primary treatment option for correcting severe scoliosis in neuromuscular disorders. Surgery in this population requires a multidisciplinary approach, careful planning, dedicated surgical procedures, and specialized after care.Methods
The guideline is based on scientific evidence and expert opinions. A multidisciplinary working group representing experts from all relevant specialties performed the research. A literature search was conducted to collect scientific evidence in answer to specific questions posed by the working group. Literature was classified according to the level of evidence.Results
For most aspects of the treatment scientific evidence is scarce and only low level cohort studies were found. Nevertheless, a high degree of consensus was reached about the management of patients with scoliosis in neuromuscular disorders. This was translated into a set of recommendations, which are now officially accepted as a general guideline in the Netherlands.Conclusion
In order to optimize the treatment for scoliosis in neuromuscular disorders a Dutch guideline has been composed. This evidence-based, multidisciplinary guideline addresses conservative treatment, the preoperative, perioperative, and postoperative care of scoliosis in neuromuscular disorders. 相似文献72.
73.
Blaney Davidson EN Vitters EL van Lent PL van de Loo FA van den Berg WB van der Kraan PM 《Arthritis research & therapy》2007,9(5):R102
Bone morphogenetic protein-2 (BMP-2) has been proposed as a tool for cartilage repair and as a stimulant of chondrogenesis.
In healthy cartilage, BMP-2 is hardly present, whereas it is highly expressed during osteoarthritis. To assess its function
in cartilage, BMP-2 was overexpressed in healthy murine knee joints and the effects on proteoglycan (PG) synthesis and degradation
were evaluated. Moreover, the contribution of BMP in repairing damage induced by interleukin-1 (IL-1) was investigated. Ad-BMP-2
was injected intra-articularly into murine knee joints, which were isolated 3, 7, and 21 days after injection for histology,
immunohistochemistry, and autoradiography. In addition, patellar and tibial cartilage was isolated for RNA isolation or measurement
of PG synthesis by means of 35SO4
2- incorporation. To investigate the role for BMP-2 in cartilage repair, cartilage damage was induced by intra-articular injection
of IL-1. After 2 days, Ad-BMP-2, Ad-BMP-2 + Ad-gremlin, Ad-gremlin, or a control virus was injected. Whole knee joints were
isolated for histology at day 4 or patellae were isolated to measure 35SO4
2- incorporation. BMP-2 stimulated PG synthesis in patellar cartilage on all days and in tibial cartilage on day 21. Aggrecan
mRNA expression had increased on all days in patellar cartilage, with the highest increase on day 7. Collagen type II expression
showed a similar expression pattern. In tibial cartilage, collagen type II and aggrecan mRNA expression had increased on days
7 and 21. BMP-2 overexpression also induced increased aggrecan degradation in cartilage. VDIPEN staining (indicating matrix
metalloproteinase activity) was elevated on day 3 in tibial cartilage and on days 3 and 7 in patellar cartilage, but no longer
was by day 21. Increased NITEGE staining (indicating aggrecanase activity) was found on days 7 and 21. In IL-1-damaged patellar
cartilage, BMP-2 boosted PG synthesis. Blocking of BMP activity resulted in a decreased PG synthesis compared with IL-1 alone.
This decreased PG synthesis was associated with PG depletion in the cartilage. These data show that BMP-2 boosts matrix turnover
in intact and IL-damaged cartilage. Moreover, BMP contributes to the intrinsic repair capacity of damaged cartilage. Increased
matrix turnover might be functional in replacing matrix molecules in the repair of a damaged cartilage matrix. 相似文献
74.
Series resistance compensation for whole-cell patch-clamp studies using a membrane state estimator 总被引:2,自引:0,他引:2 下载免费PDF全文
Whole-cell patch-clamp techniques are widely used to measure membrane currents from isolated cells. While suitable for a broad range of ionic currents, the series resistance (R(s)) of the recording pipette limits the bandwidth of the whole-cell configuration, making it difficult to measure rapid ionic currents. To increase bandwidth, it is necessary to compensate for R(s). Most methods of R(s) compensation become unstable at high bandwidth, making them hard to use. We describe a novel method of R(s) compensation that overcomes the stability limitations of standard designs. This method uses a state estimator, implemented with analog computation, to compute the membrane potential, V(m), which is then used in a feedback loop to implement a voltage clamp; we refer to this as state estimator R(s) compensation. To demonstrate the utility of this approach, we built an amplifier incorporating state estimator R(s) compensation. In benchtop tests, our amplifier showed significantly higher bandwidths and improved stability when compared with a commercially available amplifier. We demonstrated that state estimator R(s) compensation works well in practice by recording voltage-gated Na(+) currents under voltage-clamp conditions from dissociated neonatal rat sympathetic neurons. We conclude that state estimator R(s) compensation should make it easier to measure large rapid ionic currents with whole-cell patch-clamp techniques. 相似文献
75.
Both temperature fluctuations and East Asian monsoons have driven plant diversification in the karst ecosystems from southern China 下载免费PDF全文
Hanghui Kong Fabien L. Condamine AJ Harris Junlin Chen Bo Pan Michael Möller Van Sam Hoang Ming Kang 《Molecular ecology》2017,26(22):6414-6429
Karst ecosystems in southern China are species‐rich and have high levels of endemism, yet little is known regarding the evolutionary processes responsible for the origin and diversification of karst biodiversity. The genus Primulina (Gesneriaceae) comprises ca. 170 species endemic to southern China with high levels of ecological (edaphic) specialization, providing an exceptional model to study the plant diversification in karsts. We used molecular data from nine chloroplast and 11 nuclear regions and macroevolutionary analyses to assess the origin and cause of species diversification due to palaeoenvironmental changes and edaphic specialization in Primulina. We found that speciation was positively associated with changes in past temperatures and East Asian monsoons through the evolutionary history of Primulina. Climatic change around the mid‐Miocene triggered an early burst followed by a slowdown of diversification rate towards the present with the climate cooling. We detected different speciation rates among edaphic types, and transitions among soil types were infrequently and did not impact the overall speciation rate. Our findings suggest that both global temperature changes and East Asian monsoons have played crucial roles in floristic diversification within the karst ecosystems in southern China, such that speciation was higher when climate was warmer and wetter. This is the first study to directly demonstrate that past monsoon activity is positively correlated with speciation rate in East Asia. This case study could motivate further investigations to assess the impacts of past environmental changes on the origin and diversification of biodiversity in global karst ecosystems, most of which are under threat. 相似文献
76.
Adebola AJ Raji James V Anderson Olufisayo A Kolade Chike D Ugwu Alfred GO Dixon Ivan L Ingelbrecht 《BMC plant biology》2009,9(1):118-11
Background
Cassava (Manihot esculenta Crantz), a starchy root crop grown in tropical and subtropical climates, is the sixth most important crop in the world after wheat, rice, maize, potato and barley. The repertoire of simple sequence repeat (SSR) markers for cassava is limited and warrants a need for a larger number of polymorphic SSRs for germplasm characterization and breeding applications. 相似文献77.
Longiflorum and Asiatic lilies of the genus Lilium of the family Liliaceae are two important groups of modern lily cultivars.One of the main trends of lily breeding is to realize introgression between these groups.With cut style pollination and embryo rescue,distant hybrids between the two groups have been obtained.However,the F1 hybrids are highly sterile or some of them could produce a small number of 2n gametes,and their BC1 progenies are usually triploids.Dutch lily breeders have selected many cultivars... 相似文献
78.
Saskia Braber Paul AJ Henricks Frans P Nijkamp Aletta D Kraneveld Gert Folkerts 《Respiratory research》2010,11(1):1-11
Background
The inhalation of allergens by allergic asthmatics results in the early asthmatic response (EAR), which is characterized by acute airway obstruction beginning within a few minutes. The EAR is the earliest indicator of the pathological progression of allergic asthma. Because the molecular mechanism underlying the EAR is not fully defined, this study will contribute to a better understanding of asthma.Methods
In order to gain insight into the molecular basis of the EAR, we examined changes in protein expression patterns in the lung tissue of asthmatic rats during the EAR using 2-DE/MS-based proteomic techniques. Bioinformatic analysis of the proteomic data was then performed using PPI Spider and KEGG Spider to investigate the underlying molecular mechanism.Results
In total, 44 differentially expressed protein spots were detected in the 2-DE gels. Of these 44 protein spots, 42 corresponded to 36 unique proteins successfully identified using mass spectrometry. During subsequent bioinformatic analysis, the gene ontology classification, the protein-protein interaction networking and the biological pathway exploration demonstrated that the identified proteins were mainly involved in glycolysis, calcium binding and mitochondrial activity. Using western blot and semi-quantitative RT-PCR, we confirmed the changes in expression of five selected proteins, which further supports our proteomic and bioinformatic analyses.Conclusions
Our results reveal that the allergen-induced EAR in asthmatic rats is associated with glycolysis, calcium binding and mitochondrial activity, which could establish a functional network in which calcium binding may play a central role in promoting the progression of asthma. 相似文献79.
James M Duckers Dennis J Shale Robert A Stockley Nichola S Gale Bronwen AJ Evans John R Cockcroft Charlotte E Bolton 《Respiratory research》2010,11(1):173
Background
Determining the presence and extent of co-morbidities is fundamental in assessing patients with chronic respiratory disease, where increased cardiovascular risk, presence of osteoporosis and low muscle mass have been recognised in several disease states. We hypothesised that the systemic consequences are evident in a further group of subjects with COPD due to Alpha-1 Antitrypsin Deficiency (A1ATD), yet are currently under-recognised.Methods
We studied 19 patients with PiZZ A1ATD COPD and 20 age, sex and smoking matched controls, all subjects free from known cardiovascular disease. They underwent spirometry, haemodynamic measurements including aortic pulse wave velocity (aPWV), an independent predictor or cardiovascular risk, dual energy X-ray absorptiometry to determine body composition and bone mineral density.Results
The aPWV was greater in patients: 9.9(2.1) m/s than controls: 8.5(1.6) m/s, p = 0.03, despite similar mean arterial pressure (MAP). The strongest predictors of aPWV were age, FEV1% predicted and MAP (all p < 0.01). Osteoporosis was present in 8/19 patients (2/20 controls) and was previously unsuspected in 7 patients. The fat free mass and bone mineral density were lower in patients than controls (p < 0.001).Conclusions
Patients with A1ATD related COPD have increased aortic stiffness suggesting increased risk of cardiovascular disease and evidence of occult musculoskeletal changes, all likely to contribute hugely to overall morbidity and mortality. 相似文献80.
The Baja California Peninsula and surrounding landmasses harbor an abundant flora in an otherwise harsh and arid environment. Of the many plant groups native to this peninsular and insular region, passionflowers (Passiflora, Passifloraceae) are represented by several conspicuous taxa that all belong to a single lineage, section Dysosmia. Basic questions remain regarding this group, particularly the taxonomic status among the Passiflora arida complex. Therefore, we investigated the claims of endemism, habitat characteristics, and taxon boundaries with in section Dysosmia in the Baja California region using extensive sampling of herbarium specimens and iNaturalist observations. We confirmed that only one of the native Passiflora taxa (P. fruticosa) was endemic to the Baja California Peninsula, with an additional taxon (P. palmeri) considered near‐endemic. Environmental data revealed significant distinctions between the habitats of many of the native taxa as well as within the P. arida complex, especially with respect to precipitation and temperature tolerances. Geometric morphometric analyses of leaf shape were largely not successful at separating taxa, indicating leaf shape may not be a good indicator of taxon identity in this particular group. Based on ecological differences and discrete macro‐ and micromorphological features, a varietal name is here synonymized and a new combination is proposed: Passiflora pentaschista. 相似文献