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121.
122.
D'Elia D Catalano D Licciulli F Turi A Tripoli G Porcelli D Saccone C Caggese C 《Mitochondrion》2006,6(5):252-257
The oxidative phosphorylation (OXPHOS) is the primary energy-producing process of all aerobic organisms and the only cellular function under the dual control of both the mitochondrial and the nuclear genomes. Functional characterization and evolutionary study of the OXPHOS system is of great importance for the understanding of many as yet unclear aspects of nucleus-mitochondrion genomic co-evolution and co-regulation gene networks. The MitoDrome database is a web-based database which provides genomic annotations about nuclear genes of Drosophila melanogaster encoding for mitochondrial proteins. Recently, MitoDrome has included a new section annotating genomic information about OXPHOS genes in Drosophila pseudoobscura and Anopheles gambiae and their comparative analysis with their Drosophila melanogaster and human counterparts. The introduction of this new comparative annotation section into MitoDrome is expected to be a useful resource for both functional and structural genomics related to the OXPHOS system. 相似文献
123.
Kopriva S Muheim R Koprivova A Trachsel N Catalano C Suter M Brunold C 《The Plant journal : for cell and molecular biology》1999,20(1):37-44
Adenosine 5'-phosphosulphate reductase (APR) is considered to be a key enzyme of sulphate assimilation in higher plants. We analysed the diurnal fluctuations of total APR activity and protein accumulation together with the mRNA levels of three APR isoforms of Arabidopsis thaliana. The APR activity reached maximum values 4 h after light onset in both shoots and roots; the minimum activity was detected at the beginning of the night. During prolonged light, the activity remained stable and low in shoots, but followed the normal rhythm in roots. On the other hand, the activity decreased rapidly to undetectable levels within 24 h of prolonged darkness both in shoots and roots. Subsequent re-illumination restored the activity to 50% in shoots and to 20% in roots within 8 h. The mRNA levels of all three APR isoforms showed a diurnal rhythm, with a maximum at 2 h after light onset. The variation of APR2 mRNA was more prominent compared to APR1 and APR3. 35SO42- feeding experiments showed that the incorporation of 35S into reduced sulphur compounds in vivo was significantly higher in light than in the dark. A strong increase of mRNA and protein accumulation as well as enzyme activity during the last 4 h of the dark period was observed, implying that light was not the only factor involved in APR regulation. Indeed, addition of 0.5% sucrose to the nutrient solution after 38 h of darkness led to a sevenfold increase of root APR activity over 6 h. We therefore conclude that changes in sugar concentrations are also involved in APR regulation. 相似文献
124.
From the aerial parts of Rubus ulmifolius Schott three new anthrones, rubanthrone A, B and C, have been isolated. Their structures were established by spectral procedures including 1D and 2D NMR techniques and chemical derivatization. Rubanthrone A showed antimicrobial activity against Staphylococcus aureus at 4.5 mg/ml. 相似文献
125.
CM Galmarini A Kertesz R Oliva J Porta F C Galmarini 《Cancer immunology, immunotherapy : CII》1998,15(4):282-285
Bone metastasis in the hand is rare. The etiology is quite different from that of metastasis to other bones; bronchogenic
carcinoma is by far the most frequent case. Distal phalanges are mainly involved with irregular osteolysis and cortical destruction.
Differential diagnosis of phalangeal metastasis includes osteomyelitis, rheumatoid arthritis and gout. The prognosis is always
that of metastatic bronchial cancer with an average survival of three months. Treatment may involve distal digital amputation
or antalgic radiotherapy. A case of bronchogenic carcinoma with metastasis to the thumb is presented. The metastasis was located
in the distal phalanx of the left thumb. The primary tumor was located in the lung. Treatment consisted of amputation. The
overall survival was five months. 相似文献
126.
Proteins immunologically related to intermediate filaments have been identified in the sperm fibrous sheath but remain uncharacterized. We isolated and characterized a novel intermediate filament-related protein (FS39) localized to the fibrous sheath of the sperm tail. We used Northern blot analysis to establish that FS39 is transcribed predominantly in the testis of mice >18-20 days old. At this age, spermatogenesis has proceeded to the development of the first round haploid spermatids. In situ hybridization revealed that FS39 mRNA is first detectable in late step 3 spermatids, is at its highest level during steps 9 and 10, and diminishes in steps 13 and 14. Western blot analysis identified a single protein of 39 kDa in mouse and rat testis and epididymis, suggesting the protein is conserved in rodents. Indirect immunofluorescence localized FS39 to the fibrous sheath of the sperm tail, and in testis sections expression was detected from step 13 and step 14 spermatids onward, indicating FS39 is under translational control. Southern blot analysis showed FS39 to be a single copy gene, and hybridization to human genomic DNA suggested that a human equivalent gene is present. These results demonstrate that FS39 is transcribed in testis tissue during the haploid phase of spermatogenesis, is present in mature sperm, and codes for a novel 39-kDa intermediate filament-related protein of the fibrous sheath. 相似文献
127.
Filippo Catalano Giuseppe Branciforte Roberto Catanzaro Carmelo Bentivegna Rosanna Cipolla Giuseppe Nuciforo Alfio Brogna 《Helicobacter》1999,4(3):178-184
Background. Helicobacter pylori eradication has become the standard treatment for peptic ulcer disease. H. pylori –eradicating triple therapy with omeprazole plus two antibiotics has been used until recently; however, the efficacy of pantoprazole and antibiotics for H. pylori eradication has not been researched thoroughly until now. The aim of this randomized clinical trial was to verify the efficacy of triple oral therapy comparing the effects of pantoprazole using two different doses versus omeprazole twice daily in H. pylori eradication, in ulcer healing and relapses, and in gastritis improvement.
Materials and Methods. We enrolled 243 patients with H. pylori– positive duodenal ulcer and randomized them into three treatment groups: 84 patients (group Ome40) were assigned to receive omeprazole, 20 mg twice daily, plus amoxicillin, 1 gm twice daily, and clarithromycin, 500 mg twice daily for 10 days; 79 patients (group Pan40) were treated with pantoprazole, 40 mg daily, plus amoxicillin and clarithromycin at the same doses as those of group Ome40; and 80 patients (group Pan80) were treated with pantoprazole, 40 mg twice daily, plus amoxicillin and clarithromycin at the same doses as those of group Ome40.
Results. Ulcer healing was observed in 81 of 84 patients (96.4%) in group Ome40; in 66 of 79 patients (83.5%) in group Pan40; and in 77 of 80 patients (96.2%) in group Pan80. H. pylori was eradicated in 79 of 84 patients (94%) in group Ome40; in 63 of 79 patients (79.7%) in group Pan40; and in 75 of 80 patients (93.7%) in group Pan80.
Conclusions. We found that 10-day triple therapy with amoxicillin, clarithromycin, and either pantoprazole, 80 mg daily, or omeprazole, 40 mg daily, is highly effective in ulcer healing and is very well tolerated, achieving the 90% cure recommended for an ideal first-line anti– H. pylori positive duodenal ulcer treatment regimen. 相似文献
Materials and Methods. We enrolled 243 patients with H. pylori– positive duodenal ulcer and randomized them into three treatment groups: 84 patients (group Ome40) were assigned to receive omeprazole, 20 mg twice daily, plus amoxicillin, 1 gm twice daily, and clarithromycin, 500 mg twice daily for 10 days; 79 patients (group Pan40) were treated with pantoprazole, 40 mg daily, plus amoxicillin and clarithromycin at the same doses as those of group Ome40; and 80 patients (group Pan80) were treated with pantoprazole, 40 mg twice daily, plus amoxicillin and clarithromycin at the same doses as those of group Ome40.
Results. Ulcer healing was observed in 81 of 84 patients (96.4%) in group Ome40; in 66 of 79 patients (83.5%) in group Pan40; and in 77 of 80 patients (96.2%) in group Pan80. H. pylori was eradicated in 79 of 84 patients (94%) in group Ome40; in 63 of 79 patients (79.7%) in group Pan40; and in 75 of 80 patients (93.7%) in group Pan80.
Conclusions. We found that 10-day triple therapy with amoxicillin, clarithromycin, and either pantoprazole, 80 mg daily, or omeprazole, 40 mg daily, is highly effective in ulcer healing and is very well tolerated, achieving the 90% cure recommended for an ideal first-line anti– H. pylori positive duodenal ulcer treatment regimen. 相似文献
128.
Microsatellite variation in Drosophila melanogaster and Drosophila simulans: a reciprocal test of the ascertainment bias hypothesis 总被引:2,自引:1,他引:1
Interspecific comparisons of microsatellite loci have repeatedly shown that
the loci are longer and more variable in the species from which they are
derived (the focal species) than are homologous loci in other (nonfocal)
species. There is debate as to whether this is due to directional evolution
or to an ascertainment bias during the cloning and locus selection
processes. This study tests these hypotheses by performing a reciprocal
study. Eighteen perfect dinucleotide microsatellite loci identified from a
Drosophila simulans library screen and 18 previously identified in an
identical Drosophila melanogaster library screen were used to survey
natural populations of each species. No difference between focal and
nonfocal species was observed for mean PCR fragment length. However,
heterozygosity and number of alleles were significantly higher in the focal
species than in the nonfocal species. The most common allele in the
Zimbabwe population of both species was sequenced for 31 of the 36 loci.
The length of the longest stretch of perfect repeat units is, on average,
longer in the focal species than in the non-focal species. There is a
positive correlation between the length of the longest stretch of perfect
repeats and heterozygosity. The difference in heterozygosity can thus be
explained by a reduction in the length of the longest stretch of perfect
repeats in the nonfocal species. Furthermore, flanking-sequence length
difference was noted between the two species at 58% of the loci sequenced.
These data do not support the predictions of the directional-evolution
hypothesis; however, consistent with the ascertainment bias hypothesis, the
lower variability in nonfocal species is an artifact of the microsatellite
cloning and isolation process. Our results also suggest that the magnitude
of ascertainment bias for repeat unit length is a function of the
microsatellite size distribution in the genomes of different species.
相似文献
129.
Prospects for estimating nucleotide divergence with RAPDs 总被引:11,自引:0,他引:11
The technique of random amplification of polymorphic DNA (RAPD), which is
simply polymerase chain reaction (PCR) amplification of genomic DNA by a
single short oligonucleotide primer, produces complex patterns of anonymous
polymorphic DNA fragments. The information provided by these banding
patterns has proved to be of great utility for mapping and for verification
of identity of bacterial strains. Here we consider whether the degree of
similarity of the banding patterns can be used to estimate nucleotide
diversity and nucleotide divergence. With haploid data, fragments generated
by RAPD-PCR can be treated in a fashion very similar to that for
restriction-fragment data. Amplification of diploid samples, on the other
hand, requires consideration of the fact that presence of a band is
dominant to absence of the band. After describing a method for estimating
nucleotide divergence on the basis of diploid samples, we summarize the
restrictions and criteria that must be met when RAPD data are used for
estimating population genetic parameters.
相似文献
130.