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61.

Background  

Vertebrate alpha (α)- and beta (β)-globin gene families exemplify the way in which genomes evolve to produce functional complexity. From tandem duplication of a single globin locus, the α- and β-globin clusters expanded, and then were separated onto different chromosomes. The previous finding of a fossil β-globin gene (ω) in the marsupial α-cluster, however, suggested that duplication of the α-β cluster onto two chromosomes, followed by lineage-specific gene loss and duplication, produced paralogous α- and β-globin clusters in birds and mammals. Here we analyse genomic data from an egg-laying monotreme mammal, the platypus (Ornithorhynchus anatinus), to explore haemoglobin evolution at the stem of the mammalian radiation.  相似文献   
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64.
Ribonuclease (Ribonucleate nucleotide 2'-transferase E.C. 2.7.7.17) activity in serum of patients with chronic granulocytic leukaemia measured at pH 4.5-6.0 amounts to more than three times of that in serum of healthy subjects. At pH 6.0-8.0 the elevation of ribonuclease activity in serum of patients with chronic granulocytic leukaemia is less pronounced and amounts to about two times of that in normal ones. Using chromatography on CM Sephadex C-50 column, serum ribonuclease of both normal and chronic granulocytic leukaemia patients was separated into five distinct fractions. In serum of healthy subjects ribonuclease fractions denoted I-V contribute to 10; 21; 29; 22, and 18 percent of the total ribonuclease activity. In the serum of patients with chronic granulocytic leukaemia a decrease in ribonuclease fraction III to merely 17 percent and an increase in contribution of fraction IV to 32 percent of total ribonuclease activity could be observed. The comparison of each individual concentration of fraction in normal and leukaemia patients serum reveals, that ribonuclease fraction IV will increase about 3 times. A less pronounced increase could also be found for fractions I, II and V. However, ribonuclease fraction IV may be supposed to carry more than 50 percent of the whole extra load of ribonuclease present in the serum of chronic granulocytic leukaemia patients.  相似文献   
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66.

Background

Androstenone is one of the major compounds responsible for boar taint, a pronounced urine-like odor produced when cooking boar meat. Several studies have identified quantitative trait loci (QTL) for androstenone level on Sus scrofa chromosome (SSC) 6. For one of the candidate genes in the region SULT2A1, a difference in expression levels in the testis has been shown at the protein and RNA level.

Results

Haplotypes were predicted for the QTL region and their effects were estimated showing that haplotype 1 was consistently related with a lower level, and haplotype 2 with a higher level of androstenone. A recombinant haplotype allowed us to narrow down the QTL region from 3.75 Mbp to 1.94 Mbp. An RNA-seq analysis of the liver and testis revealed six genes that were differentially expressed between homozygotes of haplotypes 1 and 2. Genomic sequences of these differentially expressed genes were checked for variations within potential regulatory regions. We identified one variant located within a CpG island that could affect expression of SULT2A1 gene. An allele-specific expression analysis in the testis did not show differential expression between the alleles of SULT2A1 located on the different haplotypes in heterozygous animals. However a synonymous mutation C166T (SSC6: 49,117,861 bp in Sscrofa 10.2; C/T) was identified within the exon 2 of SULT2A1 for which the haplotype 2 only had the C allele which was higher expressed than the T allele, indicating haplotype-independent allelic-imbalanced expression between the two alleles. A phylogenetic analysis for the 1.94 Mbp region revealed that haplotype 1, associated with low androstenone level, originated from Asia.

Conclusions

Differential expression could be observed for six genes by RNA-seq analysis. No difference in the ratio of C:T expression of SULT2A1 for the haplotypes was found by the allele-specific expression analysis, however, a difference in expression between the C over T allele was found for a variation within SULT2A1, showing that the difference in androstenone levels between the haplotypes is not caused by the SNP in exon 2.  相似文献   
67.
Lung fibrosis is a major cause of mortality and morbidity in systemic sclerosis (SSc). However, its pathogenesis still needs to be elucidated. We examined whether the alteration of certain proteins in bronchoalveolar lavage fluid (BALF) might have a protective or a causative role in the lung fibrogenesis process. For this purpose we compared the BALF protein profile obtained from nine SSc patients with lung fibrosis (SScFib+) with that obtained from six SSc patients without pulmonary fibrosis (SScFib-) by two-dimensional gel electrophoresis (2-DE). Only spots and spot-trains that were consistently expressed in a different way in the two study groups were taken into consideration. In total, 47 spots and spot-trains, corresponding to 30 previously identified proteins in human BALF, showed no significant variation between SScFib+ patients and SScFib- patients, whereas 24 spots showed a reproducible significant variation in the two study groups. These latter spots corresponded to 11 proteins or protein fragments, including serum albumin fragments (13 spots), 5 previously recognized proteins (7 spots), and 4 proteins (3 spots) that had not been previously described in human BALF maps, namely calumenin, cytohesin-2, cystatin SN, and mitochondrial DNA topoisomerase 1 (mtDNA TOP1). Mass analysis did not determine one protein-spot. The two study groups revealed a significant difference in BALF protein composition. Whereas levels of glutathione S-transferase P (GSTP), Cu–Zn superoxide dismutase (SOD) and cystatin SN were downregulated in SScFib+ patients compared with SScFib- patients, we observed a significant upregulation of α1-acid glycoprotein, haptoglobin-α chain, calgranulin (Cal) B, cytohesin-2, calumenin, and mtDNA TOP1 in SScFib+ patients. Some of these proteins (GSTP, Cu–Zn SOD, and cystatin SN) seem to be involved in mechanisms that protect lungs against injury or inflammation, whereas others (Cal B, cytohesin-2, and calumenin) seem to be involved in mechanisms that drive lung fibrogenesis. Even if the 2-DE analysis of BALF did not provide an exhaustive identification of all BALF proteins, especially those of low molecular mass, it allows the identification of proteins that might have a role in lung fibrogenesis. Further longitudinal studies on larger cohorts of patients will be necessary to assess their usefulness as predictive markers of disease.  相似文献   
68.

Background  

Metabolically versatile soil bacteria Burkholderia cepacia complex (Bcc) have emerged as opportunistic pathogens, especially of cystic fibrosis (CF). Previously, we initiated the characterization of the phenylacetic acid (PA) degradation pathway in B. cenocepacia, a member of the Bcc, and demonstrated the necessity of a functional PA catabolic pathway for full virulence in Caenorhabditis elegans. In this study, we aimed to characterize regulatory elements and nutritional requirements that control the PA catabolic genes in B. cenocepacia K56-2.  相似文献   
69.

Background

Mucopolysaccharidosis type IIIA (MPS IIIA) is the most common of the mucopolysaccharidoses. The disease is caused by a deficiency of the lysosomal enzyme sulphamidase and results in the storage of the glycosaminoglycan (GAG), heparan sulphate. MPS IIIA is characterised by widespread storage and urinary excretion of heparan sulphate, and a progressive and eventually profound neurological course. Gene therapy is one of the few avenues of treatment that hold promise of a sustainable treatment for this disorder.

Methods

The murine sulphamidase gene cDNA was cloned into a lentiviral vector and high-titre virus produced. Human MPS IIIA fibroblast cultures were transduced with the sulphamidase vector and analysed using molecular, enzymatic and metabolic assays. High-titre virus was intravenously injected into six 5-week old MPS IIIA mice. Three of these mice were pre-treated with hyperosmotic mannitol. The weight of animals was monitored and GAG content in urine samples was analysed by polyacrylamide gel electrophoresis.

Results

Transduction of cultured MPS IIIA fibroblasts with the sulphamidase gene corrected both the enzymatic and metabolic defects. Sulphamidase secreted by gene-corrected cells was able to cross correct untransduced MPS IIIA cells. Urinary GAG was found to be greatly reduced in samples from mice receiving the vector compared to untreated MPS IIIA controls. In addition, the weight of treated mice became progressively normalised over the 6-months post-treatment.

Conclusion

Lentiviral vectors appear promising vehicles for the development of gene therapy for MPS IIIA.  相似文献   
70.

Background

Despite recommendations for outpatient management, low risk patients with lower respiratory tract infections (LRTIs) are often hospitalized. This survey analyzed perceptions of physicians, nurses, patients and relatives about feasibility of outpatient management and required duration of hospital stay.

Methods

We performed a prospective, observational questionnaire survey in hospitalized patients with LRTI as part of a multicenter trial. Treating physicians and nurses, patients and their relatives were asked on admission and before discharge about feasibility of outpatient treatment over 5 dimensions (medical, nursing, organizational factors, and patients' and relatives' preferences) using continuous scales.

Results

On admission, 12.6% of physicians, 15.1% of nurses, 18.0% of patients and 5.2% of relatives believed that outpatient treatment would be possible. Before hospital discharge, 31.1% of physicians, 32.2% of nurses, 11.6% of patients and 4.1% of relatives thought that earlier discharge would have been feasible. Medical factors were the most frequently perceived motives for inpatient management. These perceptions were similar in all LRTI subgroups and independent of disease severity and associated expected mortality risks as assessed by the Pneumonia Severity Index (PSI).

Conclusion

Independent of type and severity of respiratory tract infection, the misperceived high severity and expected mortality and morbidity were the predominant reasons why treating physicians, nurses, patients and their relatives unanimously believed that inpatient management was necessary. Better assessment and communication about true expected medical risks might contribute to a pathway to shorten in-hospital days and to introduce a more risk-targeted and individually tailored allocation of health-care resources.

Trial Registration

NCT00350987  相似文献   
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