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981.
Most U-rich small nuclear ribonucleoproteins (snRNPs) are complexes that mediate the splicing of pre-mRNAs. U7 snRNP is an exception in that it is not involved in splicing but is a key factor in the unique 3′ end processing of replication-dependent histone mRNAs. However, by introducing controlled changes in the U7 snRNA histone binding sequence and in the Sm motif, it can be used as an effective tool for gene therapy. The modified U7 snRNP (U7 Sm OPT) is thus not involved in the processing of replication-dependent histone pre-mRNA but targets splicing by inducing efficient skipping or inclusion of selected exons. U7 Sm OPT is of therapeutic importance in diseases that are an outcome of splicing defects, such as myotonic dystrophy, Duchenne muscular dystrophy, amyotrophic lateral sclerosis, β-thalassemia, HIV-1 infection and spinal muscular atrophy. The benefits of using U7 Sm OPT for gene therapy are its compact size, ability to accumulate in the nucleus without causing any toxic effects in the cells, and no immunoreactivity. The risk of transgene misregulation by using U7 Sm OPT is also low because it is involved in correcting the expression of an endogenous gene controlled by its own regulatory elements. Altogether, using U7 Sm OPT as a tool in gene therapy can ensure lifelong treatment, whereas an oligonucleotide or other drug/compound would require repeated administration. It would thus be strategic to harness these unique properties of U7 snRNP and deploy it as a tool in gene therapy. 相似文献
982.
Patrycja Ledwoń Fosca Errante Anna Maria Papini Paolo Rovero Rafal Latajka 《化学与生物多样性》2021,18(2):e2000833
Cosmeceutical field, which merges cosmetics and pharmaceuticals, is nowadays a highly investigated research area, because a scientific demonstration of the claimed bioactivity of new cosmeceutical ingredients is increasingly requested. In fact, an aspect differentiating traditional cosmetics from cosmeceuticals is the identification and characterization of the active ingredients and demonstrating its efficacy in the claimed activity. An interesting group of bioactive cosmeceutical ingredients are peptides, which due to their particular properties, meets most of the requirements presented by the cosmeceutical industry when composing new formulas. In this context, beside bioactivity, two additional aspects have been recently considered, when dealing with peptides as cosmeceutical ingredients: bioavailability and stability. We describe herein novel methods applied in order to enhance peptides skin-penetration and stability, reviewing both scientific articles and patents, issued in the cosmeceutical arena. 相似文献
983.
984.
985.
Maciej K. Konopiński 《Molecular ecology resources》2023,23(2):348-354
Nucleotide diversity remains an important statistic in population genetic/genomic studies. Although recent advances in massive sequencing make generating sequence data sets cheaper and faster, currently used technologies often introduce substantial amounts of missing nucleotides in their output. A novel method of estimating π from data sets containing missing data – pixy - has also recently been proposed. In this study, the pixy estimator, πpixy, was compared to average weighted nucleotide diversity, πW. The estimators were tested both on sequences simulated in fastsimcoal and real sequence sets. Both sets were modified by random insertion of missing nucleotides. Weighted nucleotide diversity performed better in all pairwise comparisons. It was characterized by a smaller error and a narrower distribution of the results. πpixy tends to overestimate the nucleotide diversity when both the proportion of missing data and the level of variation is low. Of the two estimators, only πW estimated the true nucleotide diversity in a part of the simulations. A simple formula for estimating πW allows for easy integration of the estimator in packages such as pixy, which would allow obtaining more precise estimates of nucleotide diversity either in a sliding window or for discrete genomic regions. 相似文献
986.
Koceva-Chyła A Gwoździński K Kochman A Stolarska A Jóźwiak Z 《Cellular & molecular biology letters》2003,8(1):179-183
Protection from doxorubicin-induced lipid peroxidation in vivo by two pyrroline and pyrrolidine nitroxides, Pirolin, PL, and Pirolid, PD, was examined in the heart tissue of rats treated with this drug. The level of lipid peroxidation was estimated on the basis of MDA content. A considerable (three-fold) increase in the MDA amount was found in heart homogenates from rats injected with doxorubicin, whereas no significant changes in MDA content compared to control were observed in cardiomyocytes treated with the nitroxides (Pirolin or Pirolid) only. Pirolin injected simultaneously with doxorubicin showed antioxidative effect and markedly attenuated lipid peroxidation in the heart tissue caused by this drug. In contrast to Pirolin, structurally related Pirolid was ineffective in the protection of heart myocytes from DOX-induced lipid peroxidation. 相似文献
987.
Maurizio Scarpa Zsuzsanna Almássy Michael Beck Olaf Bodamer Iain A Bruce Linda De Meirleir Nathalie Guffon Encarna Guillén-Navarro Pauline Hensman Simon Jones Wolfgang Kamin Christoph Kampmann Christina Lampe Christine A Lavery Elisa Leão Teles Bianca Link Allan M Lund Gunilla Malm Susanne Pitz Michael Rothera Catherine Stewart Anna Tylki-Szymańska Ans van der Ploeg Robert Walker Jiri Zeman James E Wraith 《Orphanet journal of rare diseases》2011,6(1):1-18
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Mucopolysaccharidosis type II (MPS II) is a rare, life-limiting, X-linked recessive disease characterised by deficiency of the lysosomal enzyme iduronate-2-sulfatase. Consequent accumulation of glycosaminoglycans leads to pathological changes in multiple body systems. Age at onset, signs and symptoms, and disease progression are heterogeneous, and patients may present with many different manifestations to a wide range of specialists. Expertise in diagnosing and managing MPS II varies widely between countries, and substantial delays between disease onset and diagnosis can occur. In recent years, disease-specific treatments such as enzyme replacement therapy and stem cell transplantation have helped to address the underlying enzyme deficiency in patients with MPS II. However, the multisystem nature of this disorder and the irreversibility of some manifestations mean that most patients require substantial medical support from many different specialists, even if they are receiving treatment. This article presents an overview of how to recognise, diagnose, and care for patients with MPS II. Particular focus is given to the multidisciplinary nature of patient management, which requires input from paediatricians, specialist nurses, otorhinolaryngologists, orthopaedic surgeons, ophthalmologists, cardiologists, pneumologists, anaesthesiologists, neurologists, physiotherapists, occupational therapists, speech therapists, psychologists, social workers, homecare companies and patient societies.Take-home message
Expertise in recognising and treating patients with MPS II varies widely between countries. This article presents pan-European recommendations for the diagnosis and management of this life-limiting disease. 相似文献988.
P Boroń R Flisiak E Bobrowska W Hilgier T Szpakowicz B Pytel 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1991,46(50-52):984-986
An effect of Aminosteril-Hepa intravenous infusions or plasmapheresis on selected amino acids, ammonia, alpha-aminonitrogen serum levels and serum GGTP activity was analysed in 28 patients with liver cirrhosis with and without hepatic encephalopathy. The patients were given protein controlled dietary treatment. It was found, that plasmapheresis exerted more potent effect on previously elevated ammonia and serum alpha-aminonitrogen levels as well as serum GGTP activity than intravenous infusions of Aminosteril-Hepa. It was clearly seen in patients with liver cirrhosis without hepatic encephalopathy. Aminosteril-Hepa intravenous infusions decreased serum glutamine levels to higher degree than plasmapheresis. Both types of therapy have had no significant effect on serum phenylalanine, tyrosine, and tryptophan levels in all patients. 相似文献
989.
Frits A. Wijburg Bernard Bénichou Daniel G. Bichet Lorne A. Clarke Gabriela Dostalova Alejandro Fainboim Andreas Fellgiebel Cassiano Forcelini Kristina An Haack Robert J. Hopkin Michael Mauer Behzad Najafian C. Ronald Scott Suma P. Shankar Beth L. Thurberg Camilla T?ndel Anna Tylki-Szymańska Uma Ramaswami 《PloS one》2015,10(5)
Trial Design
This analysis characterizes the degree of early organ involvement in a cohort of oligo-symptomatic untreated young patients with Fabry disease enrolled in an ongoing randomized, open-label, parallel-group, phase 3B clinical trial.Methods
Males aged 5–18 years with complete α-galactosidase A deficiency, without symptoms of major organ damage, were enrolled in a phase 3B trial evaluating two doses of agalsidase beta. Baseline disease characteristics of 31 eligible patients (median age 12 years) were studied, including cellular globotriaosylceramide (GL-3) accumulation in skin (n = 31) and kidney biopsy (n = 6; median age 15 years; range 13–17 years), renal function, and glycolipid levels (plasma, urine).Results
Plasma and urinary GL-3 levels were abnormal in 25 of 30 and 31 of 31 patients, respectively. Plasma lyso-GL-3 was elevated in all patients. GL-3 accumulation was documented in superficial skin capillary endothelial cells (23/31 patients) and deep vessel endothelial cells (23/29 patients). The mean glomerular filtration rate (GFR), measured by plasma disappearance of iohexol, was 118.1 mL/min/1.73 m2 (range 90.4–161.0 mL/min/1.73 m2) and the median urinary albumin/creatinine ratio was 10 mg/g (range 4.0–27.0 mg/g). On electron microscopy, renal biopsy revealed GL-3 accumulation in all glomerular cell types (podocytes and parietal, endothelial, and mesangial cells), as well as in peritubular capillary and non-capillary endothelial, interstitial, vascular smooth muscle, and distal tubules/collecting duct cells. Lesions indicative of early Fabry arteriopathy and segmental effacement of podocyte foot processes were found in all 6 patients.Conclusions
These data reveal that in this small cohort of children with Fabry disease, histological evidence of GL-3 accumulation, and cellular and vascular injury are present in renal tissues at very early stages of the disease, and are noted before onset of microalbuminuria and development of clinically significant renal events (e.g. reduced GFR). These data give additional support to the consideration of early initiation of enzyme replacement therapy, potentially improving long-term outcome.Trial Registration
ClinicalTrials.gov NCT00701415 相似文献990.
DH lines derived from cabbage cvs. Kamienna G?owa, S?awa z Enkhuizen and Langendijker, representing R1 generation, were analysed by the use of RAPD markers for their diversity and uniformity. For the evaluation of genetic diversity, eight primers yielding informative bands were used. Of the total of 83 RAPD bands scored in this study, 16.9% were polymorphic between a set of 13 DH lines. The similarity of the DH lines, estimated by Jaccard's coefficient, was depicted in the UPGMA dendrogram. Fourteen generated informative RAPD bands allowed the identification of DH lines developed from each cultivar. The evaluation of the uniformity for six closely related DH lines was possible by the use of three primers which generate one or two polymorphic bands. The lack of differences among ten plants of the five investigated DH lines manifested their uniformity. One line showed intraline polymorphism with two RAPD primers. The occurrence of the differences at the molecular level among ten plants indicated that their parental R0 plant was probably obtained from somatic cells, not by androgenesis. 相似文献