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21.
Free dorsoulnar perforator flap transfers for the reconstruction of severely injured digits 总被引:1,自引:0,他引:1
Inada Y Tamai S Kawanishi K Omokawa S Akahane M Shimobayashi M Tsuruzono M Takakura Y Inada M 《Plastic and reconstructive surgery》2004,114(2):411-420
The aim of this study was to investigate the feasibility of transferring the free dorsoulnar perforator flap nourished by the cutaneous perforator branched dorsoulnar artery to reconstruct severely injured fingers under upper arm anesthesia. Between April of 2001 and April of 2002, 13 free dorsoulnar perforator flaps were used in 13 patients. There were 11 men and two women ranging in age from 18 to 64 years, with an average age of 38 years. The affected fingers were one thumb, four index fingers, five middle fingers, two ring fingers, and one little finger. All cases were performed under upper arm anesthesia combined with intravenous local anesthesia. The operative time ranged from 103 to 140 minutes, with an average time of 120 minutes. The flap size ranged from 1 x 3 to 3 x 4 cm, and was transferred from the same forearm of the injured finger. All donor sites were closed primarily without a skin graft. The aim of reconstruction for fingers was to repair a traumatic defect (five cases), partial necrosis following replantation (two cases), and soft-tissue defects resulting from resection of a scar (three cases) and to revascularize ischemic fingers (three cases). All flaps survived completely. After repair of the flow-through circulation of the common digital artery and ischemic finger, a postoperative angiogram showed the vascular patency and hypervascularity of the reconstructed fingers, and the patients' complaints were reduced. The free dorsoulnar perforator flap under regional anesthesia is first reported; it may become one valuable option as a very small flap for the treatment of repairing intercalated or segmental defects as a flow-through flap for soft-tissue defects and ischemic fingers. 相似文献
22.
Koji?HattoriEmail author Ken?Ikeuchi Yusuke?Morita Yoshinori?Takakura 《Arthritis research & therapy》2004,7(1):R38
Osteoarthritis (OA) is one of the most prevalent chronic conditions. The histological cartilage changes in OA include surface
erosion and irregularities, deep fissures, and alterations in the staining of the matrix. The reversibility of these chondral
alterations is still under debate. It is expected that clinical and basic science studies will provide the clinician with
new scientific information about the natural history and optimal treatment of OA at an early stage. However, a reliable method
for detecting microscopic changes in early OA has not yet been established. We have developed a novel system for evaluating
articular cartilage, in which the acoustic properties of the articular cartilage are measured by introducing an ultrasonic
probe into the knee joint under arthroscopy. The purpose of this study was to assess microscopic cartilage damage in OA by
using this cartilage evaluation system on collagenase-treated articular cartilage in vivo and in vitro. Ultrasonic echoes from articular cartilage were converted into a wavelet map by wavelet transformation. On the wavelet map,
the maximum magnitude and echo duration were selected as quantitative indices. Using these indices, the articular cartilage
was examined to elucidate the relationships of the ultrasonic analysis with biochemical, biomechanical and histological analyses.
In the in vitro study, the maximum magnitude decreased as the duration of collagenase digestion increased. Correlations were observed between
the maximum magnitude and the proteoglycan content from biochemical findings, and the maximum magnitude and the aggregate
modulus from biomechanical findings. From the histological findings, matrix staining of the surface layer to a depth of 500
μm was closely related to the maximum magnitude. In the in vivo study, the maximum magnitude decreased with increasing duration of the collagenase injection. There was a significant correlation
between the maximum magnitude and the aggregate modulus. The evaluation system therefore successfully detected microscopic
changes in degenerated cartilage with the use of collagen-induced OA. 相似文献
23.
Fujita T Makishima D Akiyama K Hayashi H 《Bioscience, biotechnology, and biochemistry》2002,66(8):1697-1705
New convulsive compounds, brasiliamides A (1) and B (2), were isolated by activity-guided fractionation from okara fermented with a soil isolate of Penicillium brasilianum Batista JV-379. Their structures were elucidated on the basis of spectral and chemical evidence and by X-ray crystallography of the hydrogenated product of 2. In the 1H- and 13C-NMR spectra of 2, the signals were complicated, all being doubled or broadened in several deuterated solvents at room temperature. The conformational change of 2 was clarified as the rotational isomerization of amide bonds in solution by NMR measurements at various temperatures. Four rotamers of 2 at two amide bonds were presented at -60 degrees C in CDCl3, whereas only two isomers were apparent at room temperature, owing to rapid rotation of one of the amide bonds. Brasiliamides A and B respectively showed convulsive activity against silkworms with ED50 values of 300 and 50 microg/g of diet. 相似文献
24.
Suzuki Y Kurano M Arai Y Nakashita H Doi Y Usami R Horikoshi K Yamaguchi I 《Bioscience, biotechnology, and biochemistry》2002,66(12):2537-2542
Chemical regulation of secondary-metabolite synthesis was investigated through the improvement of poly-3-hydroxybutyrate (PHB) production in transgenic tobacco plants by the use of enzyme inhibitors. Two tobacco lines, BC3 and rCAB8, that produce PHB in both the cytosol and plastids were used. An acetyl-CoA carboxylase inhibitor, D-(+)-Quizalofop-ethyl, increased PHB accumulation in both lines 2-fold. The accumulation rate of plastidial PHB in the rCAB8 line was 2.5-fold higher than that of cytosolic PHB in the BC3 line. A specific inhibitor of 3-hydroxy-3-methylglutaryl-CoA reductase, mevastatin, also increased PHB accumulation but only in the BC3 line. These results indicated that chemical regulation of the native metabolic flows by the specific enzyme inhibitors increased secondary-metabolite production in the transgenic tobacco plants we used. 相似文献
25.
Ishikawa K Mihara Y Shimba N Ohtsu N Kawasaki H Suzuki E Asano Y 《Protein engineering》2002,15(7):539-543
Escherichia blattae non-specific acid phosphatase (EB-NSAP) possesses a pyrophosphate-nucleoside phosphotransferase activity, which is C-5'-position selective. Current mutational and structural data were used to generate a mutant EB-NSAP for a potential industrial application as an effective and economical protein catalyst in synthesizing nucleotides from nucleosides. First, Gly74 and Ile153 were replaced by Asp and Thr, respectively, since the corresponding replacements in the homologous enzyme from Morganella morganii reduced the K(m) value for inosine and thus increased the productivity of 5'-IMP. We determined the crystal structure of G74D/I153T, which has a reduced K(m) value for inosine, as expected. The tertiary structure of G74D/I153T was virtually identical to that of the wild-type. In addition, neither of the introduced side chains of Asp74 and Thr153 is directly involved in the interaction with inosine in a hypothetical binding mode of inosine to EB-NSAP, although both residues are situated near a potential inosine-binding site. These findings suggested that a slight structural change caused by an amino acid replacement around the potential inosine-binding site could significantly reduce the K(m) value. Prompted by this hypothesis, we designed several mutations and introduced them to G74D/I153T, to decrease the K(m) value further. This strategy produced a S72F/G74D/I153T mutant with a 5.4-fold lower K(m) value and a 2.7-fold higher V(max) value as compared to the wild-type EB-NSAP. 相似文献
26.
Bovine immature oocytes acquire developmental competence during meiotic arrest in vitro 总被引:9,自引:0,他引:9
To test the hypothesis that oocytes require time to acquire developmental competence during meiotic arrest, we investigated the effects of butyrolactone I (BL I), a potent and specific inhibitor of cyclin-dependent kinase, on the developmental competence of bovine oocytes after in vitro fertilization (IVF) following release from meiotic arrest. In the present study, 4 culture conditions were used: addition of BSA or fetal bovine serum (FBS) under 2 oxygen tensions (5% vs. 20%) during meiotic arrest with 100-microM BL I. The developmental competence to the blastocyst stage was higher (P < 0.01) in oocytes that were arrested in FBS-supplemented medium under 5% O2 (37%) than in oocytes that were arrested under other conditions (5%-24%) or that matured directly following follicle aspiration (23%). The time course of nuclear maturation of BL I-treated oocytes was also examined. The results demonstrated that oocytes treated with BL I start germinal vesicle (GV) breakdown and reach the metaphase II stage 5.5-6.0 h earlier than nonarrested oocytes. The developmental rates to the blastocyst stage of BL I-treated oocytes matured for 15.5 and 21 h were higher (P < 0.05) than those of nontreated oocytes matured for 21 and 26.5 h, respectively. These results demonstrate that bovine immature oocytes, which were arrested at the GV stage with BL I in FBS-supplemented medium under low oxygen tension, acquire higher developmental competence during meiotic arrest. 相似文献
27.
Yamada M Tohno Y Takakura Y Tohno S Moriwake Y Minami T 《Biological trace element research》2003,91(1):57-66
To elucidate compositional changes of the tendons with aging, the authors investigated age-related changes of element contents
in the tendon of the iliopsoas muscle by inductively coupled plasma-atomic emission spectrometry. The subjects consisted of
14 men and 14 women, ranging in age from 4 to 102 yr. The insertion tendons of the iliopsoas were removed from the cadavers
after ordinary dissection and also surgically from patients with congenital dislocation of the hip. It was found that both
Mg and P in the tendon of the iliopsoas muscle increased significantly with aging, but the other elements, such as S, Ca,
Na, Zn, Fe, and Si, hardly changed with aging.
With regard to the relationship among element contents, extremely significant correlations were found between P and S contents,
between Mg and Na contents, and between S and Zn contents. In addition, very significant correlations were found between Si
and either S or Zn contents. However, there was no significant correlation between Ca and P contents. These results revealed
that with regard to age-related changes of element contents and the relationships among element contents, the tendon of the
iliopsoas muscle was different from the Achilles tendon, in which both Mg and P decreased significantly with aging and there
were significant correlations each other among the contents of S, Mg, and P. 相似文献
28.
The effects of polyethylene glycol and dimethyl sulfoxide (PEG/DMSO) treatment of donor cells on the fusion and subsequent development of bovine nuclear transfer embryos using mammary gland epithelial (MGE) cells before electrofusion (fresh MGE cells) was studied. The same study was conducted on those cells that were frozen and stored in liquid nitrogen, and then thawed (frozen-thawed MGE cells). Experiment 1 showed that the exposure time and pH of PEG/DMSO solution affected the fusion of nuclear transfer, and that a higher fusion rate was obtained when fresh MGE cells were exposed to PEG/DMSO solution at pH 8.0 for 5 min. In Experiment 2, the proportion of fused oocytes with fresh PEG/DMSO-treated cells (70 +/- 6%) was significantly higher than that with non-treated cells (50 +/- 13%, p < 0.05). The same tendency was observed when frozen-thawed cells as donor nuclei were used (48 +/- 6% vs. 34 +/- 12%, p < 0.05). In addition, PEG/DMSO treatment has neither harmful nor beneficial effects on the cleavage and development of the blastocyst stage of reconstructed embryos (p > 0.05). The fusion and cleavage rates of frozen-thawed cells were significantly lower than those of fresh cells (p < 0.05). After 10 blastocysts, derived from fresh PEG/DMSO-treated cells, were transferred to five recipient heifers, one live female calf was obtained. Experiment 3 showed that PEG/DMSO treatment reduced the viability of both fresh and frozen-thawed MGE cells (p < 0.05). We conclude that the PEG/DMSO treatment of fresh MGE cells, as well as the frozen-thawed cells, before electrofusion has a positive effect on the fusion of nuclear transfer without decreasing the in vitro development of reconstructed embryos. 相似文献
29.
Toshiyuki Shibata Kohki Nagayama Ryusuke Tanaka Kuniko Yamaguchi Takashi Nakamura 《Journal of applied phycology》2003,15(1):61-66
The inhibitory effects of brown algal phlorotannins on secretory phospholipase A2s (sPLA2s), lipoxygenases (LOXs) and cyclooxygenases (COXs) were determined with an in vitro assay. Oligomers of phloroglucinol; eckol (a trimer), phlorofucofuroeckol A (a pentamer), dieckol (a hexamer) and 8,8-bieckol (a hexamer) isolated from the brown alga Eisenia bicyclis had pronounced inhibitory effects on sPLA2 from porcine pancreas and bee venom (IC50 100–200 M). The phlorotannins inhibited LOX activity more effectively than the well-known LOX inhibitors; resveratrol and epigallocatechin gallate. 8,8-Bieckol, the strongest LOX inhibitor in this study, inhibited soybean LOX and 5-LOX with IC50 values of 38 and 24 M, respectively. Negligible or very weak effects of the phlorotannins on COX-1 and COX-2 were found, except for an inhibitory effect of dieckol on COX-1 (74.7%) and of eckol on COX-2 (43.2%) at 100 M. 相似文献
30.