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101.
Chuang DC Mardini S Lin SH Chen HC 《Plastic and reconstructive surgery》2004,113(1):126-32; discussion 133-5
Gracilis functioning free-muscle transplantation for the correction of pure facial paralysis has been a preferred method used by many reconstructive microsurgeons. However, for complex facial paralysis, the deficits include facial paralysis along with soft-tissue, mucosa, and/or skin defects. No adequate solution has been proposed. Treatment requests in those patients are not only for facial reanimation but also for correction of the defects. Of 161 patients with facial paralysis treated with gracilis functioning free-muscle transplantation from 1986 to 2002, eight patients (5 percent) presented with complex deficits requiring not only facial reanimation but also aesthetic correction of tissue defects. The tissue defects included an intraoral defect created following contracture release (one patient), infra-auricular radiation dermatitis with contour depression (one patient), temporal depression following a temporalis muscle-fascia transfer (one patient), ear deformity (two patients), and infra-auricular atrophic tissue with contour depression (three patients). A compound flap, consisting of a gracilis muscle with its overlying skin paddle separated into two components, was transferred for simultaneous correction of both problems. The blood supply to the gracilis and to the skin paddle originated from the same source vessel and therefore required the anastomosis of only one set of vessels. The versatility of this compound flap allows for a wide arc of rotation of the skin paddle around the muscle. All flaps were transferred successfully without complications. Satisfactory results of facial reanimation were recorded in five patients after all stages were completed. The remaining three patients are undergoing physical therapy and waiting for revision of the skin paddle. 相似文献
102.
The concept of qth order Hamming ball for general bidirectional associative memories (GBAMs) is presented, which results in an enhanced recall capability. A technique based on the minimum overlap algorithm (MOA) is proposed to deal with the separability problem of the qth order Hamming balls. Simulation results show that the recall capability obtained by using the proposed method is indeed larger than that obtained by using the conventional method. 相似文献
103.
Sun KH Sun GH Su Y Chang CI Chuang MJ Wu WL Chu CY Tang SJ 《Apoptosis : an international journal on programmed cell death》2004,9(6):833-841
Amyloid precursor protein (APP) has several caspase cleavage sites in its C-terminal cytoplasmic domain and N-terminal extracellular domain. Caspase cleavages of APP at its cytosolic tail may result in releasing the domain and inducing cell death. During apoptosis, the N-terminal domain may also be processed at amino acids 197 and 219 by caspases leading to unmasking of an acidic-rich region (AR). In this study, AR-exposing APP was shown to inhibit cell growth after transfection into RBA-1 astrocytes and BV-2 microglial cells. The recombinant AR from residue 220 to 288 of APP (APP220-288) was produced and its biological activities were analyzed. APP220-288 induced morphological changes, cell death, and DNA fragmentation in BV-2 and RBA-1 cells. However, AR was determined to have no apparent effects in suspension cells, erythroleukemia K562 cells, and Jurkat T cells. The cytotoxicity was depending on negative charge cluster and the apoptotic activity of AR was attributed to the inhibition of cell adhesion. In BV-2 microglial cells, AR significantly stimulated Fas expression, although expressions of the pro-inflammatory cytokine genes were not detected. APP220-288 also induced nitric oxide synthase (iNOS) expression and nitric oxide (NO) production. These findings indicate that the acidic-rich domain of APP may have apoptotic activity due to inhibition of cell adhesion and induction of iNOS and Fas expressions. Moreover, unmasking the apoptosis-induced AR may activate and exacerbate glial cells which in turn lead to further progression of the death program. 相似文献
104.
Chuang IC Jhao CM Yang CH Chang HC Wang CW Lu CY Chang YJ Lin SH Huang PL Yang LC 《Arthritis research & therapy》2004,6(1):R7-R14
Endogenous opioid peptides have an essential role in the intrinsic modulation and control of inflammatory pain, which could be therapeutically useful. In this study, we established a muscular electroporation method for the gene transfer of pro-opiomelanocortin (POMC) in vivo and investigated its effect on inflammatory pain in a rat model of rheumatoid arthritis. The gene encoding human POMC was inserted into a modified pCMV plasmid, and 0-200 microg of the plasmid-POMC DNA construct was transferred into the tibialis anterior muscle of rats treated with complete Freund's adjuvant (CFA) with or without POMC gene transfer by the electroporation method. The safety and efficiency of the gene transfer was assessed with the following parameters: thermal hyperalgesia, serum adrenocorticotropic hormone (ACTH) and endorphin levels, paw swelling and muscle endorphin levels at 1, 2 and 3 weeks after electroporation. Serum ACTH and endorphin levels of the group into which the gene encoding POMC had been transferred were increased to about 13-14-fold those of the normal control. These levels peaked 1 week after electroporation and significantly decreased 2 weeks after electroporation. Rats that had received the gene encoding POMC had less thermal hypersensitivity and paw swelling than the non-gene-transferred group at days 3, 5 and 7 after injection with CFA. Our promising results showed that transfer of the gene encoding POMC by electroporation is a new and effective method for its expression in vivo, and the analgesic effects of POMC cDNA with electroporation in a rat model of rheumatoid arthritis are reversed by naloxone. 相似文献
105.
The separation of an extract prepared from the stems of the previously uninvestigated Hibiscus taiwanensis led to the isolation of three new phenylpropanoid esters, (7S,8S)-demethylcarolignan E (1), hibiscuwanin A (2), hibiscuwanin B (3), in addition to eight known ones. The structures of these compounds were elucidated by spectroscopic and chemical transformation studies. In cytotoxicity evaluation of the isolates, 9,9'-O-feruloyl-(-)-secoisolaricinresinol (8) showed strong cytotoxic activity against human lung carcinoma and breast carcinoma cell lines in an in vitro cytotoxicity assay with EC(50) values of 1.8 and 3.9 microg/mL, respectively. 相似文献
106.
107.
Chuang CW Cheng MT Lin JT Hsien HY Hung HY Hwang JC 《The Chinese journal of physiology》2003,46(2):71-81
The purpose of the current study was to examine where arginine vasopressin (AVP) inhibits respiration by direct action on the areas of the ventrolateral medulla (VLM) in the rat. The animal was anesthetized by urethane (1.2 g/kg, i.p.), paralyzed with gallamine triethiodide, and artificially ventilated. Catheterization of the femoral artery and vein, and bilateral vagotomy were performed. The rat was then placed upon a stereotaxic instrument in a prone position. The phrenic nerve was separated and cut peripherally. Phrenic nerve activity (PNA) was monitored at normocapnia and hypercapnia in hyperoxia. Microinjection of AVP into various subregions of the VLM was then performed. In response to AVP microinjection, a transient period of apnea and then a significant decrease in PNA amplitude were observed. Arterial blood pressure was unchanged. This inhibition of PNA with AVP treatment was site-specific, attenuated by raising CO2 concentration, and totally abolished by pretreatment with AVP V1A receptor antagonist. Data of the present study indicate that endogenous resource of AVP may produce an inhibitory effect upon respiration via AVP receptors presented on neurons within the VLM. 相似文献
108.
Glew RH Casados JK Huang YS Chuang LT VanderJagt DJ 《Prostaglandins, leukotrienes, and essential fatty acids》2002,67(4):217-222
The purpose of this study was to determine the fatty acid composition of the serum phospholipids of children with sickle cell disease (SCD) in Nigeria and to compare the relative fluidity of the acyl chains of the serum phospholipids of controls versus the subjects with SCD. It is widely accepted that the fatty acid composition of an individual's serum phospholipids reflects that of their tissue phospholipids. An alteration in the fatty acid composition of membrane phospholipids could affect critical membrane-dependent enzymes and processes (e.g., ion and solute transport, hormone-receptor interactions, signal transduction pathways). We found a significant reduction in the content of polyunsaturated n-3 fatty acids in the phospholipids of subjects with SCD which could result in a reduction of the fluidity of their tissue membranes. Specifically, there was a 40-50% reduction in the proportion of total n-3 fatty acids in subjects with SCD. On the basis of calculated melting points and double bond indices of the acyl chains of the serum phospholipids, the phospholipids of the children with SCD are less fluid relative to those of their healthy counterparts. In addition, we determined that linoleic acid, arachidonic acid, and stearic acid were the major determinants of the fluidity of the acyl chains of the serum phospholipids of the healthy controls and children with SCD. 相似文献
109.
Background. Even after partial gastrectomy, Helicobacter pylori may persist in the residual stomach but be less abundant in the bacterial load. H. pylori stool antigen is a reliable noninvasive tool to detect H. pylori infection in patients without gastrectomy. We thus test whether [ 1 ] the course of H. pylori eradication therapy could be diminished [ 2 ]; stool antigen can effectively detect H. pylori infection for the patients with gastrectomy. Methods. One hundred and eight patients who had undergone partial gastrectomy were enrolled to receive panendoscopy and provided stool samples for H. pylori stool antigen within 3 days after endoscopy. The H. pylori‐infected patients were then randomized to receive either a 3‐ or 7‐day triple therapy for H. pylori eradication. Six weeks later, to evaluate the success of H. pylori eradication, patients received a follow‐up endoscopy and again provided stool samples for H. pylori stool antigen. Results. Seventy out of 108 patients, proven to have H. pylori infection, were evenly randomized into 3‐day and 7‐day therapy groups. The H. pylori eradication rates were similar between the 3‐day and 7‐day triple therapy (90.9 vs. 93.8%, p > .05). Before therapy, the H. pylori stool antigen was 93% sensitive and 100% specific to detect H. pylori. After therapy, H. pylori stool antigen remain 100% sensitive and 88.3% specific to detect the failure of eradication therapy. Conclusion. H. pylori stool antigen is a highly reliable tool to screen H. pylori infection before therapy and to assess the success of eradication therapy in partial gastrectomy patients. To eradicate H. pylori infection for patients with partial gastrectomy, the duration of triple therapy can be shortened. 相似文献
110.
Interleukin enhancer binding factor (ILF) binds to the interleukin-2 (IL-2) promoter and regulates IL-2 gene expression. In this study, the 3D structure of the DNA-binding domain of ILF was determined by multidimensional NMR spectroscopy. NMR structure analysis revealed that the DNA-binding domain of ILF is a new member of the winged helix/forkhead family, and that its wing 2 contains an extra alpha-helix. This is the first study to report the presence of a C-terminal alpha-helix in place of a typical wing 2 in a member of this family. This structural difference may be responsible for the different DNA-binding specificity of ILF compared to other winged helix/forkhead proteins. Our deletion studies of the fragments of ILF also suggest that the C-terminal region plays a regulatory role in DNA binding. 相似文献