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1.
Summary The use of reticulated polyurethane foam as a support material for the immobilization of methanogenic associations and its application to the anaerobic treatment of fine particulate solid wastes was investigated. The colonization of polyurethane support particles in a continuous upflow reactor fed on a mixture of acetate, propionate and butyrate, was both rapid and dense. The combination of rumen microorganisms and colonized support particles in a two-phase digester resulted in an efficient anaerobic decomposition of papermill sludge.  相似文献   
2.
Nasal mucociliary clearance was measured in both healthy subjects and patients with chronic sinusitis using saccharin granule technique. Nasal mucociliary transit time (ST) was significantly slower in the patients with chronic sinusitis compared with that in controls (p less than 0.005). Nasal mucus collected from each nasal cavity was used for in vitro bullfrog palate clearance studies and compared to the in vivo nasal ST. Mucociliary clearance rate (MTR) on frog palate was 12.5 +/- 2.5 mm/min in the mucus from control subjects, 6.1 +/- 1.5 mm/min in the mucus from the patients. The difference was statistically significant (p less than 0.005). The MTR on frog palate in the patients whose nasal ST was within normal range was significantly slower than that in controls (p less than 0.005), but not significantly different from that in the patients whose nasal ST was over the normal range. These results suggest that the nasal mucous properties which decreased the mucociliary clearance on frog palate did not contribute to the mucociliary clearance of the patients who had a normal one. No significant correlation existed between MTR on frog palate and nasal ST in both control and chronic sinusitis. In chronic sinusitis patients, decelerated nasal ST was recovered significantly by normal saline nebulization compared with the value before the nebulization (p less than 0.01). None of the significant change of ST was observed in control before and after the nebulization.  相似文献   
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T Ohkawa  K Majima    S Maeda 《Journal of virology》1994,68(10):6619-6625
Sequence analysis of the BamHI F fragment of the genome of Bombyx mori nuclear polyhedrosis virus (BmNPV) revealed an open reading frame whose deduced amino acid sequence had homology to those of cysteine proteases of the papain superfamily. The putative cysteine protease sequence (BmNPV-CP) was 323 amino acids long and showed 35% identity to a cysteine proteinase precursor from Trypanosoma brucei. Of 36 residues conserved among cathepsins B, H, L, and S and papain, 31 were identical in BmNPV-CP. In order to determine the activity and function of the putative cysteine protease, a BmNPV mutant (BmCysPD) was constructed by homologous recombination of the protease gene with a beta-galactosidase gene cassette. BmCysPD-infected BmN cell extracts were significantly reduced in acid protease activity compared with wild-type virus-infected cell extracts. The cysteine protease inhibitor E-64 [trans-epoxysuccinylleucylamido-(4-guanidino)butane] inhibited wild-type virus-expressed protease activity. Deletion of the cysteine protease gene had no significant effect on viral growth or polyhedron production in BmN cells, indicating that the cysteine protease was not essential for viral replication in vitro. However, B. mori larvae infected with BmCysPD showed symptoms different from those of wild-type BmNPV-infected larvae, e.g., less degradation of the body, including fat body cells, white body surface color due presumably to undegraded epidermal cells, and an increase in the number of polyhedra released into the hemolymph. This is the first report of (i) a virus-encoded protease with activity on general substrates and (ii) evidence that a virus-encoded protease may play a role in degradation of infected larvae to facilitate horizontal transmission of the virus.  相似文献   
6.
K Majima  R Kobara    S Maeda 《Journal of virology》1993,67(12):7513-7521
Homologous regions (hrs) (hr1,hr2-left,hr2-right,hr3,hr4-left,hr 4-right, and hr5) similar to those found in the Autographa californica nuclear polyhedrosis virus (AcNPV) genome were found in the Bombyx mori NPV (BmNPV) genome. The BmNPV hrs contained two to eight repeats of a homologous nucleotide sequence which were on average about 75 bp long. All of these homologous sequence repeats contained a 26-bp-long palindrome motif with an EcoRI or EcoRI-like site at its core. The consensus sequence of the BmNPV hrs showed 95% conservation with respect to those found in AcNPV. Nucleotide sequence analysis indicated that hr2-left and hr2-right of BmNPV evolved from an ancestor similar to hr2 of AcNPV by inversion, cleavage, and ligation. The polarities of the BmNPV and AcNPV hrs were conserved except for that of hr4-left. Within hr4-right of BmNPV, four repeats of a previously underscribed palindrome motif were found. Bmhr5D, a BmNPV mutant which lacked hr5, replicated at a rate similar to that of wild-type BmNPV in BmN cells and silkworm larvae, indicating that hr5 was not essential for viral replication. After ten passages of Bmhr5D in BmN cells, no detectable changes in its genome were observed by restriction endonuclease analysis. The evolution and divergence of the BmNPV genome are also discussed.  相似文献   
7.

Background

Long-term benefits in animal breeding programs require that increases in genetic merit be balanced with the need to maintain diversity (lost due to inbreeding). This can be achieved by using optimal contribution selection. The availability of high-density DNA marker information enables the incorporation of genomic data into optimal contribution selection but this raises the question about how this information affects the balance between genetic merit and diversity.

Methods

The effect of using genomic information in optimal contribution selection was examined based on simulated and real data on dairy bulls. We compared the genetic merit of selected animals at various levels of co-ancestry restrictions when using estimated breeding values based on parent average, genomic or progeny test information. Furthermore, we estimated the proportion of variation in estimated breeding values that is due to within-family differences.

Results

Optimal selection on genomic estimated breeding values increased genetic gain. Genetic merit was further increased using genomic rather than pedigree-based measures of co-ancestry under an inbreeding restriction policy. Using genomic instead of pedigree relationships to restrict inbreeding had a significant effect only when the population consisted of many large full-sib families; with a half-sib family structure, no difference was observed. In real data from dairy bulls, optimal contribution selection based on genomic estimated breeding values allowed for additional improvements in genetic merit at low to moderate inbreeding levels. Genomic estimated breeding values were more accurate and showed more within-family variation than parent average breeding values; for genomic estimated breeding values, 30 to 40% of the variation was due to within-family differences. Finally, there was no difference between constraining inbreeding via pedigree or genomic relationships in the real data.

Conclusions

The use of genomic estimated breeding values increased genetic gain in optimal contribution selection. Genomic estimated breeding values were more accurate and showed more within-family variation, which led to higher genetic gains for the same restriction on inbreeding. Using genomic relationships to restrict inbreeding provided no additional gain, except in the case of very large full-sib families.  相似文献   
8.
The specificity of highly purified carboxyl proteinase from Pycnoporus coccineus (formerly designated Trametes sanguined) was investigated with oligopeptides at pH 2.7. Hydrolysis of oxidized insulin peptide Bl ~ B16 was observed at two peptide bonds (His10-Leu11 and Ala14-Leu15) during 3-hr incubation. The enzyme did not hydrolyze oxidized insulin peptide B15 ~ B24. Hydrolysis of angiotensin (formerly designated angiotensin II) was observed at the Tyr4-Ile5 bond. Hydrolysis of proangiotensin (formerly designated angiotensin I) was also at the Tyr4-Ile5 bond. In conclusion, peptide bonds which have a hydrophobic amino acid in the P1 position (as defined by Schechter and Berger, Biochem. Biophys. Res. Commun., 27, 157 (1967)) are preferentially cleaved by the trypsinogen activating carboxyl proteinase of Pycnoporus coccineus.  相似文献   
9.
The specificity of highly purified alkaline proteinase B (EC 3.4.21.14) from thermophilic Streptomyces rectus var. proteolyticus was investigated with an oxidized insulin B chain. Hydrolysis of the oxidized insulin B chain in a 4-hr incubation was observed mainly at three peptide bonds (Phe24-Phe25, Leu15-Tyr16 and Leu11-Val12) and additionally at six others (Leu6-CySO3H7, Gln4-His5, Leu17-Val18, His5-Leu6, Glu13-Ala14, Asn3-Gln4).

Hydrolysis of angiotensin (formerly designated angiotensin II) was observed at the Tyr4-Ile5 bond. Hydrolysis of proangiotension (formerly designated angiotensin I) was observed at the Tyr4-Ile5 and Phe8-His9 bonds.  相似文献   
10.
Mitochondrial damage is a well known cause of mitochondria-related diseases. A major mechanism underlying the development of mitochondria-related diseases is thought to be an increase in intracellular oxidative stress produced by impairment of the mitochondrial electron transport chain (ETC). However, clear evidence of intracellular free radical generation has not been clearly provided for mitochondrial DNA (mtDNA)-damaged cells. In this study, using the novel fluorescence dye, 2-[6-(4'-hydroxy)phenoxy-3H-xanthen-3-on-9-yl]benzoic acid (HPF), which was designed to detect hydroxyl radicals (*OH), intracellular free radical formation was examined in 143B cells (parental cells), 143B-rho(0) cells (mtDNA-lacking cells), 87 wt (cybrid), and cybrids of 4977-bp mtDNA deletion (common deletion) cells containing the deletion with 0%, 5%, 50% and >99% frequency (HeLacot, BH5, BH50 and BH3.12, respectively), using a laser confocal microscope detection method. ETC inhibitors (rotenone, 3-nitropropionic acid, thenoyltrifluoroacetone, antimycin A and sodium cyanide) were also tested to determine whether inhibitor treatment increased intracellular reactive oxygen species (ROS) generation. A significant increase in ROS for 143B-rho(0) cells was observed compared with 143B cells. However, for the 87 wt cybrid, no increase was observed. An increase was also observed in the mtDNA-deleted cells BH50 and BH3.12. The ETC inhibitors increased intracellular ROS in both 143B and 143B-rho(0) cells. Furthermore, in every fluorescence image, the fluorescence dye appeared localized around the nuclei. To clarify the localization, we double-stained cells with the dye and MitoTracker Red. The resulting fluorescence was consistently located in mitochondria. Furthermore, manganese superoxide dismutase (MnSOD) cDNA-transfected cells had decreased ROS. These results suggest that more ROS are generated from mitochondria in ETC-inhibited and mtDNA-damaged cells, which have impaired ETC.  相似文献   
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