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91.
Franc-Christophe Baurens Stéphanie Bocs Mathieu Rouard Takashi Matsumoto Robert NG Miller Marguerite Rodier-Goud Didier MBéguié-A-MBéguié Nabila Yahiaoui 《BMC plant biology》2010,10(1):149
Background
Comparative sequence analysis of complex loci such as resistance gene analog clusters allows estimating the degree of sequence conservation and mechanisms of divergence at the intraspecies level. In banana (Musa sp.), two diploid wild species Musa acuminata (A genome) and Musa balbisiana (B genome) contribute to the polyploid genome of many cultivars. The M. balbisiana species is associated with vigour and tolerance to pests and disease and little is known on the genome structure and haplotype diversity within this species. Here, we compare two genomic sequences of 253 and 223 kb corresponding to two haplotypes of the RGA08 resistance gene analog locus in M. balbisiana "Pisang Klutuk Wulung" (PKW). 相似文献92.
Mostafa Alam Shahryar Karami Meysam Mohammadikhah Ashkan Badkoobeh Mohsen Golkar Kamyar Abbasi Reza Sayyad Soufdoost Lotfollah Kamali Hakim Sahar Talebi Reza Abdollahi Namanloo Ahmed Hussain Artak Heboyan Hamid Tebyaniyan 《Cell biochemistry and function》2024,42(2):e3951
The use of photobiomodulation therapy (PBMT) may be used for treating trauma to the maxillofacial region. The effects of PBMT on maxillofacial injuries were discussed in this review article. The electronic databases Pubmed, Scopus, and Web of Science were thoroughly searched. This review included in vitro, in vivo, and clinical studies describing how PBMT can be used in maxillofacial tissue engineering and regenerative medicine. Some studies suggest that PBMT may offer a promising therapy for traumatic maxillofacial injuries because it can stimulate the differentiation and proliferation of various cells, including dental pulp cells and mesenchymal stem cells, enhancing bone regeneration and osseointegration. PBMT reduces pain and swelling after oral surgery and tooth extraction in human and animal models of maxillofacial injuries. Patients with temporomandibular disorders also benefit from PBMT in terms of reduced inflammation and symptoms. PBMT still has some limitations, such as the need for standardizing parameters. PBMT must also be evaluated further in randomized controlled trials in various maxillofacial injuries. As a result, PBMT offers a safe and noninvasive treatment option for patients suffering from traumatic maxillofacial injuries. PBMT still requires further research to establish its efficacy in clinical practice and determine the optimal parameters. 相似文献
93.
Elevated ammonium concentrations in the medium of cultivated cells have
been shown to increase the intracellular levels of uridine-5'-diphospho-
N-acetylglucosamine (UDP-GlcNAc) and uridine-5'-diphospho-N-
acetylgalactosamine (UDP-GalNAc; Ryll et al., 1994). These sugar
nucleotides are substrates for glycosyltransferases in the glycosylation
pathway. In our experiments, recombinant Chinese hamster ovary cells
producing an immunoadhesin glycoprotein (GP1-IgG) have been cultivated
under controlled cell culture conditions in the presence of different
ammonium concentrations.15N-Labeled ammonium chloride (15NH4Cl) was added
exogenously to the cell culture media to determine if ammonium was
incorporated into UDP-GlcNAc and cytidine-5'-
monophospho-N-acetylneuraminic acid (CMP-NANA) pools, and subsequently
incorporated into GP1-IgG as N-linked glycans. The intracellular pools of
UDP-activated hexosamines (UDP-GNAc) were followed during the time course
of the experiment. To assess the extent of15NH4+incorporation into the
glycans of GP1-IgG, the glycoprotein was first purified to homogeneity by
protein A chromatography. Enzymatically released N- glycans were then
analyzed by matrix-assisted laser desorption/ionization time-of-flight mass
spectrometry. N-Glycans synthesized in the presence of15NH4Cl revealed an
N-glycan-dependent increase in mass-to-charge of 2.5-4.8 Da. These results
indicate that 60-70% of the total nitrogen containing monosaccharides had
incorporated15N. Presumably,15NH4+was incorporated into GlcNAc and N-
acetylneuraminic acid as proposed earlier (Ryll et al., 1994). This might
be a universal and previously not described reaction in mammalian cells
when exposed to nonphysiological but in cell culture commonly found
concentrations of ammonium. The data presented here are of significance for
glycoprotein production in mammalian cell culture, since it has been shown
previously that elevated levels of UDP- activated hexosamines affect
N-glycan characteristics such as branching and degree of amino sugar
incorporation. In addition, our results demonstrate that isotope labeling
in combination with MALDI-TOF-MS can be used as an alternate tool to
radioactive labeling of sugar substrates in metabolic studies.
相似文献
94.
Background
Helicobacter pylori colonizes the human stomach and is associated with gastritis, peptic ulcer, and gastric cancer. This ubiquitous association between H. pylori and humans is thought to be present since the origin of modern humans. The H. pylori genome encodes for an exceptional number of restriction and modifications (R-M) systems. To evaluate if R-M systems are an adequate tool to determine the geographic distribution of H. pylori strains, we typed 221 strains from Africa, America, Asia, and Europe, and evaluated the expression of different 29 methyltransferases. 相似文献95.
Alfalfa is believed to have originated in north-western Iran and has a long history of coexistence with its bacterial symbiont Sinorhizobium in soils of Iran. However, little is known about the diversity of Sinorhizobium strains nodulating Iranian alfalfa genotypes. In this study, Sinorhizobium populations were sampled from eight different Iranian sites using three cultivars of Medicago sativa as trap host plants. A total of 982 rhizobial strains were isolated and species were identified showing a large prevalence of Sinorhizobium meliloti over Sinorhizobium medicae. Analysis of salt tolerance demonstrated a great phenotypic diversity. The genetic diversity of the Sinorhizobium isolates was analysed using BOX-PCR and enterobacterial repetitive intergenic consensus (ERIC)-PCR. Patterns ofBOX-PCR fingerprinting were statistically analysed with AMOVA to evaluate the role of plant variety and site of origin in the genetic variance observed. Results indicated that most of the total molecular variance was attributable to divergence among strains isolated from different sites and cultivars (intrapopulation, strain-by-strain variance). Moreover, the analysis showed the presence of two geographic populations (west and northwest), indicating that the effect of the site of origin could be more relevant in shaping population genetic diversity than the effect of cultivar or individual plant. 相似文献
96.
Immunisation against coccidiosis has become more reliable and effective with improved administration techniques for new vaccines. On the other hand, an ideal coccidial vaccine should contain both B- and T-cell immunogenic epitopes. Fine specificity of B-cell epitopes recognised by antibodies prepared following primary and secondary infections with Eimeria tenella were studied using "PepScan" techniques. Mapping of B-cell epitopes within an antigenic sequence from E. tenella showed that four distinct types of epitopes were recognised by the host immune system during the primary and secondary infections with the parasite. These observations demonstrated that new epitopes are also involved in induction of antibody responses following the secondary infection. 相似文献
97.
Kappa-chain constant-region gene sequences in genus Rattus: coding regions are diverging more rapidly than noncoding regions 总被引:2,自引:0,他引:2
We have determined the nucleotide sequence of a 1,200-base pair (bp)
genomic fragment that includes the kappa-chain constant-region gene (C
kappa) from two species of native Australian rodents, Rattus leucopus
cooktownensis and Rattus colletti. Comparison of these sequences with each
other and with other rodent C kappa genes shows three surprising features.
First, the coding regions are diverging at a rate severalfold higher than
that of the nearby noncoding regions. Second, replacement changes within
the coding region are accumulating at a rate at least as great as that of
silent changes. Third, most of the amino acid replacements are localized in
one region of the C kappa domain--namely, the carboxy-terminal "bends" in
the alpha-carbon backbone. These three features have previously been
described from comparisons of the two allelic forms of C kappa genes in R.
norvegicus. These data imply the existence of considerable evolutionary
constraints on the noncoding regions (based on as yet undetermined
functions) or powerful positive selection to diversify a portion of the
constant-region domain (whose physiological significance is not known).
These surprising features of C kappa evolution appear to be characteristic
only of closely related C kappa genes, since comparison of rodent with
human sequences shows the expected greater conservation of coding regions,
as well as a predominance of silent nucleotide substitutions within the
coding regions.
相似文献
98.
Three molecular markers, including start codon targeted (SCoT) polymorphism, directed amplification of minisatellite-region DNA polymerase chain reaction (DAMD-PCR), and inter simple sequence repeat (ISSR) markers, were compared in terms of their informativeness and efficiency for analysis of genetic relationships among 38 accessions of eight annual Cicer species. The results were as follows: (1) the highest level of detected polymorphism was observed for all three marker types; (2) the rate of diversity for the three marker techniques was approximately equal, and the correlation coefficients of similarity were statistically significant for all three marker systems; (3) the three molecular markers showed relatively similar phylogenetic grouping for examined species. Diversity analysis showed that Cicer reticulatum is the closest wild species to the cultivated chickpea, and this finding supports the hypothesis that C.?reticulatum is the most probable progenitor of the cultivated species. C.?bijugum, C.?judaicum, and C.?pinnatifidum were clustered together, and in other clusters C.?yamashitae and C.?cuneatum were grouped close together. To our knowledge, this is the first detailed comparison of performance among two targeted DNA region molecular markers (SCoT and DAMD-PCR) and the ISSR technique on a set of samples of Cicer. The results provide guidance for future efficient use of these molecular methods in genetic analysis of Cicer. 相似文献
99.
JS Agerholm O Andersen MB Almskou C Bendixen J Arnbjerg GP Aamand US Nielsen F Panitz AH Petersen 《Acta veterinaria Scandinavica》2004,45(3):133
To investigate the congenital complex vertebral malformation syndrome (CVM) in Holstein calves, two breeding studies were
performed including 262 and 363 cows, respectively. Cows were selected from the Danish Cattle Database based on pedigree and
insemination records. Selected cows were progeny of sires with an established heterozygous CVM genotype and pregnant after
insemination with semen from another sire with heterozygous CVM genotype. Following calving the breeders should state, if
the calf was normal and was requested to submit dead calves for necropsy. In both studies, significantly fewer CVM affected
calves than expected were obtained; a finding probably reflecting extensive intrauterine mortality in CVM affected foetuses.
The findings illustrate increased intrauterine mortality as a major potential bias in observational studies of inherited disorders. 相似文献
100.
Samson Mani Katarzyna Szymańska Cyrille Cuenin David Zaridze Karen Balassiano Sheila CS Lima Elena Matos Alexander Daudt Sergio Koifman Victor Wunsch Filho Ana MB Menezes Maria Paula Curado Gilles Ferro Thomas Vaissière Bakary S Sylla Massimo Tommasino Luis Felipe Ribeiro Pinto Paolo Boffetta Pierre Hainaut Paul Brennan Zdenko Herceg 《Epigenetics》2012,7(3):270-277
Cancers of the upper aerodigestive tract (UADT) are common forms of malignancy associated with tobacco and alcohol exposures, although human papillomavirus and nutritional deficiency are also important risk factors. While somatically acquired DNA methylation changes have been associated with UADT cancers, what triggers these events and precise epigenetic targets are poorly understood. In this study, we applied quantitative profiling of DNA methylation states in a panel of cancer-associated genes to a case-control study of UADT cancers. Our analyses revealed a high frequency of aberrant hypermethylation of several genes, including MYOD1, CHRNA3 and MTHFR in UADT tumors, whereas CDKN2A was moderately hypermethylated. Among differentially methylated genes, we identified a new gene (the nicotinic acetycholine receptor gene) as target of aberrant hypermethylation in UADT cancers, suggesting that epigenetic deregulation of nicotinic acetycholine receptors in non-neuronal tissues may promote the development of UADT cancers. Importantly, we found that sex and age is strongly associated with the methylation states, whereas tobacco smoking and alcohol intake may also influence the methylation levels in specific genes. This study identifies aberrant DNA methylation patterns in UADT cancers and suggests a potential mechanism by which environmental factors may deregulate key cellular genes involved in tumor suppression and contribute to UADT cancers.Key words: DNA methylation, upper aerodigestive tract, cancer, risk factors, biomarkers 相似文献