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61.
Novel Adeno‐Associated Viral Vector Delivering the Utrophin Gene Regulator Jazz Counteracts Dystrophic Pathology in mdx Mice 下载免费PDF全文
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An efficient adaptor long-range PCR (ALR-PCR) procedure was developed to detect genomic rearrangements in high-plasticity genomic regions between closely related strains of bacteria. The method was precisely optimized using a combination of high-speed experimental steps for the chromosomal localization and elucidation of deletions, inversions, duplications, or inserted sequences within a clone-specific flanking region. The advantages of this strategy are: (i) ready-to-use polymerase mixtures and Master mix (ready-to-use reaction mixtures with polymerase MasterAmp and buffer 2x Premix 4); (ii) a 5-min ligation procedure; (iii) rapid purification of DNA digests; (iv) optimized DNA template concentration protocol to avoid nonspecific amplification and high backgrounds; (v) long-range PCR protocol to obtain at least 9.6 kb single PCR products; (vi) two-step PCR cycling with the same annealing and extension temperature at 68 degrees C; (vii) simple design of the adaptors according to the preferred restriction endonuclease enzyme; and (viii) simple technology and equipment required. The application of this method for a tester-specific suppressive subtractive hybridization (SSH) clone of Brucella melitensis 16M revealed an 837-bp deletion and a 7255-bp DNA transfer from one chromosomal location to another for Brucella abortus 2308 used as a driver. 相似文献
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Subtype-selective nuclear hormone receptor modulators could potentially allow the development of valuable tissue-specific therapeutics. A simple biosensor that allows subtype-specific nuclear hormone receptor binding to be reflected by the growth phenotype of Escherichia coli cells has been constructed. This system will potentially enable the facile detection or evolution of subtype-selective hormone analogues. 相似文献
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Pavlok A Lapathitis G Cech S Kubelka M Lopatárová M Holý L Klíma J Motlík J Havlícek V 《Molecular reproduction and development》2005,71(2):197-208
To increase the developmental competence of bovine oocytes isolated from small, medium, and large follicles (2-3, 3-4, and 4-6 mm in diameter, respectively), we tried to modify the conditions for their in vitro culture. The first step involved conditions maintaining at least for 48 hr a reversible inhibition of the germinal vesicle breakdown (GVBD) and the second step stimulated the resumption of meiosis and completion of nuclear and cytoplasmic maturation during the subsequent 20-22 hr of culture. The effectiveness of this model depended mainly on the medium composition (reduced NaHCO3, substitution of serum with serum albumin, addition of antioxidants (curcumin), increased viscosity by agar, the reduction of oxygen concentration (within 6%-8%), the reduction of the proportion between the number of cumulus-oocyte complexes (COCs), and the reduction of the amount of a medium (within 6-7 mul per COC) to amplify the GVBD-inhibitory effect of oocyte surrounding granulosa cells. The COCs were incubated in clumps of 6-7 COCs. The effectiveness and reversibility of GVBD inhibition depended also on the duration of COCs isolation. The full reversibility of the GV block was controlled morphologically and also by measuring histone H1 and MAP kinase activities. The two-step versus one-step (24 hr) maturation technique was evaluated by the percentage of total and hatched blastocysts at day 9. When compared with one-step maturation, the two-step culture showed a slightly increased proportion of total and hatched blastocysts developed from growing follicles, mainly from the smallest category (13.9% vs. 7.1% and 9.2% vs. 3.3% for total blastocysts and hatched, respectively). However, the two-step culture of oocytes from large regressing follicles substantially reduced the blastocyst yield (9.7% vs. 39.1% and 4.9% vs. 26.7% for total blastocysts and hatched, respectively). The transfer of ten blastocysts (developed after two-step culture) to ten recipients resulted in seven pregnancies. 相似文献
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Green EC Gkoutos GV Lad HV Blake A Weekes J Hancock JM 《Bioinformatics (Oxford, England)》2005,21(12):2930-2931
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The solution NMR conformational properties of two angiotensin converting enzyme (ACE) Zn catalytic-site 36-residue peptides, with the general sequence HEMGHX23EAIGDX3, synthesized through solid-phase 9-fluorenylmethoxycarbonyl (Fmoc) chemistry, is reported. The 1H resonance assignment of Zn-bound peptides is presented and the characteristic features of the NMR solution models of the two ACE Zn(II)-bound peptides are reported. The solid-state and solution structures of the ACE C-domain catalytic site are compared while biologically important structural similarities and differences of the N- and C-terminal catalytic sites are discussed. Additionally, the structural features of the ACE substrate, the angiotensin I (AI) decapeptide, are studied using NMR spectroscopy, in order to set the structural basis for the ACE-substrate interaction in solution. 相似文献
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Annie Herbert Meena Rafiq Tra My Pham Cristina Renzi Gary A. Abel Sarah Price Willie Hamilton Irene Petersen Georgios Lyratzopoulos 《PLoS medicine》2021,18(8)
BackgroundThe diagnostic assessment of abdominal symptoms in primary care presents a challenge. Evidence is needed about the positive predictive values (PPVs) of abdominal symptoms for different cancers and inflammatory bowel disease (IBD).Methods and findingsUsing data from The Health Improvement Network (THIN) in the United Kingdom (2000–2017), we estimated the PPVs for diagnosis of (i) cancer (overall and for different cancer sites); (ii) IBD; and (iii) either cancer or IBD in the year post-consultation with each of 6 abdominal symptoms: dysphagia (n = 86,193 patients), abdominal bloating/distension (n = 100,856), change in bowel habit (n = 106,715), rectal bleeding (n = 235,094), dyspepsia (n = 517,326), and abdominal pain (n = 890,490). The median age ranged from 54 (abdominal pain) to 63 years (dysphagia and change in bowel habit); the ratio of women/men ranged from 50%:50% (rectal bleeding) to 73%:27% (abdominal bloating/distension). Across all studied symptoms, the risk of diagnosis of cancer and the risk of diagnosis of IBD were of similar magnitude, particularly in women, and younger men. Estimated PPVs were greatest for change in bowel habit in men (4.64% cancer and 2.82% IBD) and for rectal bleeding in women (2.39% cancer and 2.57% IBD) and lowest for dyspepsia (for cancer: 1.41% men and 1.03% women; for IBD: 0.89% men and 1.00% women). Considering PPVs for specific cancers, change in bowel habit and rectal bleeding had the highest PPVs for colon and rectal cancer; dysphagia for esophageal cancer; and abdominal bloating/distension (in women) for ovarian cancer. The highest PPVs of abdominal pain (either sex) and abdominal bloating/distension (men only) were for non-abdominal cancer sites. For the composite outcome of diagnosis of either cancer or IBD, PPVs of rectal bleeding exceeded the National Institute of Health and Care Excellence (NICE)-recommended specialist referral threshold of 3% in all age–sex strata, as did PPVs of abdominal pain, change in bowel habit, and dyspepsia, in those aged 60 years and over. Study limitations include reliance on accuracy and completeness of coding of symptoms and disease outcomes.ConclusionsBased on evidence from more than 1.9 million patients presenting in primary care, the findings provide estimated PPVs that could be used to guide specialist referral decisions, considering the PPVs of common abdominal symptoms for cancer alongside that for IBD and their composite outcome (cancer or IBD), taking into account the variable PPVs of different abdominal symptoms for different cancers sites. Jointly assessing the risk of cancer or IBD can better support decision-making and prompt diagnosis of both conditions, optimising specialist referrals or investigations, particularly in women.Annie Herbert and co-workers study possible relevance of common abdominal symptoms for specialist referral in UK primary care. 相似文献
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Sabat R Chanwangpong A Schneider-Burrus S Metternich D Kokolakis G Kurek A Philipp S Uribe D Wolk K Sterry W 《PloS one》2012,7(2):e31810