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51.
We developed a new and simple method to collect sections of a whole brown rice kernel for investigation of histological properties. A single kernel of rice was dehydrated through a graded ethanol series, transferred to xylene, and embedded in paraffin. During sectioning of the blocks using a rotary microtome, we used a special adhesive tape to collect and place the sections on slides so they remained flat. The use of the adhesive tape technique combined with autofluorescence characteristics allowed us to visualize cell walls throughout an entire longitudinal or transverse section of a whole rice kernel. We obtained scanning electron microscopy images of the sections to determine section quality. 相似文献
52.
Antibodies to citrullinated proteins and differences in clinical progression of rheumatoid arthritis
van der Helm-van Mil AH Verpoort KN Breedveld FC Toes RE Huizinga TW 《Arthritis research & therapy》2005,7(5):R949-R958
Antibodies to citrullinated proteins (anti-cyclic-citrullinated peptide [anti-CCP] antibodies) are highly specific for rheumatoid
arthritis (RA) and precede the onset of disease symptoms, indicating a pathogenetic role for these antibodies in RA. We recently
showed that distinct genetic risk factors are associated with either anti-CCP-positive disease or anti-CCP-negative disease.
These data are important as they indicate that distinct pathogenic mechanisms are underlying anti-CCP-positive disease or
anti-CCP-negative disease. Likewise, these observations raise the question of whether anti-CCP-positive RA and anti-CCP-negative
RA are clinically different disease entities. We therefore investigated whether RA patients with anti-CCP antibodies have
a different clinical presentation and disease course compared with patients without these autoantibodies. In a cohort of 454
incident patients with RA, 228 patients were anti-CCP-positive and 226 patients were anti-CCP-negative. The early symptoms,
tender and swollen joint count, and C-reactive protein level at inclusion, as well as the swollen joint count and radiological
destruction during 4 years of follow-up, were compared for the two groups. There were no differences in morning stiffness,
type, location and distribution of early symptoms, patients' rated disease activity and C-reactive protein at inclusion between
RA patients with and without anti-CCP antibodies. The mean tender and swollen joint count for the different joints at inclusion
was similar. At follow-up, patients with anti-CCP antibodies had more swollen joints and more severe radiological destruction.
Nevertheless, the distribution of affected joints, for swelling, bone erosions and joint space narrowing, was similar. In
conclusion, the phenotype of RA patients with or without anti-CCP antibodies is similar with respect to clinical presentation
but differs with respect to disease course. 相似文献
53.
The occurrence of cyclopropane fatty acids in the phospholipids of sheep rumen tissues 总被引:1,自引:0,他引:1
Body DR 《FEBS letters》1972,27(1):5-8
54.
In vertebrates and the cephalochordate, amphioxus, the closest vertebrate
relative, Hox genes are linked in a single cluster. Accompanying the
emergence of higher vertebrates, the Hox gene cluster duplicated in either
a single step or multiple steps, resulting in the four-cluster state
present in teleosts and tetrapods. Mammalian Hox clusters (designated A, B,
C, and D) extend over 100 kb and are located on four different chromosomes.
Reconstructing the history of the duplications and its relation to
vertebrate evolution has been problematic due to the lack of alignable
sequence information. In this study, the problem was approached by
conducting a statistical analysis of sequences from the fibrillar-type
collagens (I, II, III, and IV), genes closely linked to each Hox cluster
which likely share the same duplication history as the Hox genes. We find
statistical support for the hypothesis that the cluster duplication
occurred as multiple distinct events and that the four-cluster situation
arose by a three- step sequential process.
相似文献
55.
56.
The Olifants River, a tributary of the Limpopo River system, is one of the most polluted rivers in South Africa. In May 2011 the concentrations of metals in fish muscle tissue from two impoundments, Loskop and Flag Boshielo dams, on the Olifants River were measured and a human health risk assessment conducted to investigate whether it was safe to consume Labeo rosae from these impoundments. Labeo rosae is one of the most common pan fish in these impoundments and is readily available to rural communities. Metals are accumulating in the muscle tissue of L. rosae even although the fish populations appear to be healthy. At Loskop Dam all L. rosae analysed exceeded the recommended hazard quotient (HQ) of 1 for antimony, and less than 50% exceeded that for lead. At Flag Boshielo Dam, the recommended HQ was exceeded for lead in less than 50% of L. rosae analysed, and more than 50% exceeded that for antimony. The weekly consumption of 150?g of L. rosae muscle tissue from these impoundments may pose an unacceptable health risk to rural communities. 相似文献
57.
Zweers MC de Boer TN van Roon J Bijlsma JW Lafeber FP Mastbergen SC 《Arthritis research & therapy》2011,13(5):239
Osteoarthritis (OA) is a degenerative joint disease characterized by progressive loss of articular cartilage, subchondral bone sclerosis, osteophyte formation, and synovial inflammation, causing substantial physical disability, impaired quality of life, and significant health care utilization. Traditionally, non-steroidal anti-inflammatory drugs (NSAIDs), including selective cyclooxygenase (COX)-2 inhibitors, have been used to treat pain and inflammation in OA. Besides its anti-inflammatory properties, evidence is accumulating that celecoxib, one of the selective COX-2 inhibitors, has additional disease-modifying effects. Celecoxib was shown to affect all structures involved in OA pathogenesis: cartilage, bone, and synovium. As well as COX-2 inhibition, evidence indicates that celecoxib also modulates COX-2-independent signal transduction pathways. These findings raise the question of whether celecoxib, and potentially other coxibs, is more than just an anti-inflammatory and analgesic drug. Can celecoxib be considered a disease-modifying osteoarthritic drug? In this review, these direct effects of celecoxib on cartilage, bone, and synoviocytes in OA treatment are discussed. 相似文献
58.
M L Bermingham S C Bishop J A Woolliams R Pong-Wong A R Allen S H McBride J J Ryder D M Wright R A Skuce S WJ McDowell E J Glass 《Heredity》2014,112(5):543-551
Tuberculosis (TB) caused by Mycobacterium bovis is a re-emerging disease of
livestock that is of major economic importance worldwide, as well as being a zoonotic
risk. There is significant heritability for host resistance to bovine TB (bTB) in dairy
cattle. To identify resistance loci for bTB, we undertook a genome-wide association study
in female Holstein–Friesian cattle with 592 cases and 559 age-matched controls from
case herds. Cases and controls were categorised into distinct phenotypes: skin test and
lesion positive vs skin test negative on multiple occasions, respectively. These animals
were genotyped with the Illumina BovineHD 700K BeadChip. Genome-wide rapid association
using linear and logistic mixed models and regression (GRAMMAR), regional heritability
mapping (RHM) and haplotype-sharing analysis identified two novel resistance loci that
attained chromosome-wise significance, protein tyrosine phosphatase receptor T
(PTPRT; P=4.8 × 10−7) and myosin
IIIB (MYO3B; P=5.4 × 10−6). We estimated
that 21% of the phenotypic variance in TB resistance could be explained by all of
the informative single-nucleotide polymorphisms, of which the region encompassing the
PTPRT gene accounted for 6.2% of the variance and a further 3.6%
was associated with a putative copy number variant in MYO3B. The results from
this study add to our understanding of variation in host control of infection and suggest
that genetic marker-based selection for resistance to bTB has the potential to make a
significant contribution to bTB control. 相似文献
59.
Background
The three consensus elements at the 3' end of human introns - the branch point sequence, the polypyrimidine tract, and the 3' splice site AG dinucleotide - are usually closely spaced within the final 40 nucleotides of the intron. However, the branch point sequence and polypyrimidine tract of a few known alternatively spliced exons lie up to 400 nucleotides upstream of the 3' splice site. The extended regions between the distant branch points (dBPs) and their 3' splice site are marked by the absence of other AG dinucleotides. In many cases alternative splicing regulatory elements are located within this region.Results
We have applied a simple algorithm, based on AG dinucleotide exclusion zones (AGEZ), to a large data set of verified human exons. We found a substantial number of exons with large AGEZs, which represent candidate dBP exons. We verified the importance of the predicted dBPs for splicing of some of these exons. This group of exons exhibits a higher than average prevalence of observed alternative splicing, and many of the exons are in genes with some human disease association.Conclusion
The group of identified probable dBP exons are interesting first because they are likely to be alternatively spliced. Second, they are expected to be vulnerable to mutations within the entire extended AGEZ. Disruption of splicing of such exons, for example by mutations that lead to insertion of a new AG dinucleotide between the dBP and 3' splice site, could be readily understood even though the causative mutation might be remote from the conventional locations of splice site sequences. 相似文献60.
Kim D Baas Maarten WJ Koeter Henk C van Weert Peter Lucassen Claudi LH Bockting Karin A Wittkampf Aart H Schene 《Trials》2010,11(1):1-6