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21.
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   
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Fluorescence recovery after photobleaching (FRAP) in spontaneous multinuclear cells shows that both rat and human constitutive active/androstane receptors (CARs) are shuttling proteins with both nuclear localization signals (NLSs) and nuclear export signals (NESs). We previously identified two NLSs in rat CAR: NLS1 in the hinge region (residues 100-108) and NLS2 in the ligand-binding domain (residues 111-320). In the present study, we compared the intracellular localization signals between rat and human CARs. There was a marked difference in their intracellular localization in COS-7 cells because, unlike rat CAR, human CAR does not contain NLS1 due to an amino acid change at position 106. A CRM1-dependent leucine-rich NES, which is sensitive to an inhibitory effect of leptomycin B, was found in the cytoplasmic retention region previously identified within the ligand-binding domain of rat CAR (residues 220-258). We found that human CAR instead has a NES in the ligand-binding domain between residues 170 and 220. Also, we detected CRM1-independent C-terminal NESs between residues 317-358 of rat and human CARs. Removal of NLS1 by N-terminal truncation and mutation of xenochemical response signal caused rat CAR to localize in the cytoplasm of COS-7 cells, which we suspect is due to the masking of NLS2.  相似文献   
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Comparison of meristic characters (pored lateral line scales, vertebrae, and fin rays), and PCR-RFLP analysis in the D-loop and ND1 regions of mitochondrial DNA were performed to estimate the genetic diversity in local populations of the Japanese rosy bitterling, Rhodeus ocellatus kurumeus. In terms of meristic characters, the Fukuoka population was the largest in both range and variance of the number of pored lateral line scales and vertebrae (abdominal and caudal), and Osaka was the second, whereas the Kagawa population showed the smallest range and variance in these characters. In PCR-RFLP analysis, 11 haplotypes (3 in Fukuoka, 2 in Okayama, 2 in Kagawa, and 4 in Osaka) were observed, and nucleotide sequence divergence (NSD) was approximately two times larger in ND1 (mean, 0.61%) than in D-loop (mean, 0.31%). In the neighbor-joining (NJ) tree, based upon the NSD value in ND1, haplotypes were arranged into four clades, which corresponded to the locality of each haplotype. The Fukuoka population was conspicuously apart from the other populations (mean, 0.90% in NSD), but the remaining three showed a similar genetic distance with each other (mean, 0.48%–0.52% in NSD). In haplotype diversity of mtDNA, half the stations in Osaka and all in Kagawa were monomorphic. Especially, two haplotypes endemic to Kagawa were randomly distributed, irrespective of drainages. Rhodeus o. kurumeus in Fukuoka inhabits small rivers and creeks (open water systems), while that in Kagawa and Osaka lives in small ponds (closed water systems). Taking the information of morphology, mtDNA, and habitat into consideration, the low genetic diversity in Kagawa and Osaka populations of R. o. kurumeus is thought to be mainly the result of the isolation of their habitat. Received: January 14, 2001 / Revised: June 14, 2001 / Accepted: July 1, 2001  相似文献   
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Effects of silicon on the mechanical and chemical properties of cell walls in the second leaf of oat (Avena sativa L.) seedlings were investigated. The cell wall extensibility in the basal region of the second leaf was considerably higher than that in the middle and subapical regions. Externally applied silicon increased the cell wall extensibility in the basal region, but it did not affect the extensibility in the middle and subapical regions. The amounts of cell wall polysaccharides and phenolic compounds, such as diferulic acid (DFA) and ferulic acid (FA), per unit length were lower in the basal region than in the middle and subapical regions of the leaf, and silicon altered these amounts in the basal region. In this region, silicon decreased the amounts of matrix polymers and cellulose per unit length and of DFA and FA, both per unit length and unit matrix polymer content. Silicon treatment also lowered the activity of phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) in the basal region. In contrast, the amount of silicon in cell walls increased in response to silicon treatment in three regions. These results suggest that in the basal region, silicon reduces the net wall mass and the formation of phenolic acid-mediated cross-linkages between wall polysaccharides. Such modifications of wall architecture may be responsible for the silicon-induced increase in the cell wall extensibility in oat leaves.  相似文献   
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Background

Recent in-vitro studies have suggested that mast cells are involved in Dengue virus infection. To clarify the role of mast cells in the development of clinical Dengue fever, we compared the plasma levels of several mast cell-derived mediators (vascular endothelial cell growth factor [VEGF], soluble VEGF receptors [sVEGFRs], tryptase, and chymase) and -related cytokines (IL-4, -9, and -17) between patients with differing severity of Dengue fever and healthy controls.

Methodology/Principal Findings

The study was performed at Children''s Hospital No. 2, Ho Chi Minh City, and Vinh Long Province Hospital, Vietnam from 2002 to 2005. Study patients included 103 with Dengue fever (DF), Dengue hemorrhagic fever (DHF), and Dengue shock syndrome (DSS), as diagnosed by the World Health Organization criteria. There were 189 healthy subjects, and 19 febrile illness patients of the same Kinh ethnicity. The levels of mast cell-derived mediators and -related cytokines in plasma were measured by ELISA. VEGF and sVEGFR-1 levels were significantly increased in DHF and DSS compared with those of DF and controls, whereas sVEGFR-2 levels were significantly decreased in DHF and DSS. Significant increases in tryptase and chymase levels, which were accompanied by high IL-9 and -17 concentrations, were detected in DHF and DSS patients. By day 4 of admission, VEGF, sVEGFRs, and proteases levels had returned to similar levels as DF and controls. In-vitro VEGF production by mast cells was examined in KU812 and HMC-1 cells, and was found to be highest when the cells were inoculated with Dengue virus and human Dengue virus-immune serum in the presence of IL-9.

Conclusions

As mast cells are an important source of VEGF, tryptase, and chymase, our findings suggest that mast cell activation and mast cell-derived mediators participate in the development of DHF. The two proteases, particularly chymase, might serve as good predictive markers of Dengue disease severity.  相似文献   
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IntroductionChikungunya virus (CHIKV) is a mosquito-borne virus known to cause acute febrile illness associated with debilitating polyarthritis. In 2019, several institutions in Myanmar reported a CHIKV outbreak. There are no official reports of CHIKV cases between 2011 and 2018. Therefore, this study sought to determine the seroprevalence of CHIKV infection before the 2019 outbreak.MethodsA total of 1,544 serum samples were collected from healthy volunteers and patients with febrile illnesses in Yangon, Mandalay, and the Myeik district in 2013, 2015, and 2018. Participants ranged from one month to 65 years of age. Antibody screening was performed with in-house anti-CHIKV IgG and IgM ELISA. A neutralization assay was used as a confirmatory test.ResultsThe seroprevalence of anti-CHIKV IgM and anti-CHIKV IgG was 8.9% and 28.6%, respectively, with an overall seropositivity rate of 34.5%. A focus reduction neutralization assay confirmed 32.5% seroprevalence of CHIKV in the study population. Age, health status, and region were significantly associated with neutralizing antibodies (NAbs) and CHIKV seropositivity (p < 0.05), while gender was not (p = 0.9). Seroprevalence in 2013, 2015, and 2018 was 32.1%, 28.8%, and 37.3%, respectively. Of the clinical symptoms observed in participants with fevers, arthralgia was mainly noted in CHIKV-seropositive patients.ConclusionThe findings in this study reveal the circulation of CHIKV in Myanmar’s Mandalay, Yangon, and Myeik regions before the 2019 CHIKV outbreak. As no treatment or vaccine for CHIKV exists, the virus must be monitored through systematic surveillance in Myanmar.  相似文献   
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The substrate specificity of Serratia protease was determined using various synthetic substrates. The enzyme did not participate in the hydrolysis of di- and tri-peptides except benzoylglycylleucinamide which was split at a limited rate into hippuric acid and leucinamide. The enzyme action on larger peptides was also studied. The enzyme cleaved the gly-leu bond in eledoisin related peptide and the gly-phe bond in bradykinin. The enzyme split oxidized insulin B-chain at twelve different peptide bonds.  相似文献   
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