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Activity-differential search for amyloid-β aggregation inhibitors using LC-MS combined with principal component analysis. Bioorg Med Chem Lett 2022; 61:128613. [PMID: 35176471 DOI: 10.1016/j.bmcl.2022.128613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/31/2022] [Accepted: 02/05/2022] [Indexed: 11/02/2022]
Abstract
Aggregation of amyloid β42 (Aβ42) is one of the hallmarks of Alzheimer's disease (AD). Inhibition of Aβ42 aggregation is thus a promising approach for AD therapy. Kampo medicine has been widely used to combat dementias such as AD. Crude drug known as Shoyaku is an ingredient of Kampo that could have potential as a natural source of novel drugs. However, given that a mixture of compounds, rather than singular compounds, could contribute to the biological functions of crude drug, there are very limited studies on the structure and mechanism of each constituent in crude drug which may have anti-Aβ42 aggregation properties. Herein we provide an efficient method, using LC-MS combined with principal component analysis (PCA), to search for activity-dependent compounds that inhibit Aβ42 aggregation from 46 crude drug extracts originating from 18 plants. Only 5 extracts (Kakou, Kayou, Gusetsu, Rensu, and Renbou) from lotus demonstrated differentially inhibitory activities depending on the part of the plant from which they are derived (e.g. petiole, leaf, root node, stamen, and receptacle, respectively). To compare the anti-aggregative properties of compounds of active crude drug with those of inactive crude drug, these extracts were subjected to LC-MS measurement, followed by PCA. From 12 candidate compounds identified from the analysis, glucuronized and glucosidized quercetin, as well as 6 flavonoids (datiscetin, kaempferol, morin, robinetin, quercetin, and myricitrin), including catechol or flatness moiety suppressed Aβ42 aggregation, whereas curcumol, a sesquiterpene, did not. In conclusion, this study offers a new activity-differential methodology to identify bioactive natural products in crude drugs that inhibit Aβ42 aggregation and that could be applied to future AD therapies.
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2
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Role of the carboxy groups of triterpenoids in their inhibition of the nucleation of amyloid β42 required for forming toxic oligomers. Chem Commun (Camb) 2018; 54:6272-6275. [DOI: 10.1039/c8cc03230k] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The carboxy group of ursane-type triterpenoids plays a critical role in the suppression of toxic Aβ42 nucleation by targeting the monomer to trimer.
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3
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Semisynthesis and Structure-Activity Studies of Uncarinic Acid C Isolated from Uncaria rhynchophylla as a Specific Inhibitor of the Nucleation Phase in Amyloid β42 Aggregation. JOURNAL OF NATURAL PRODUCTS 2016; 79:2521-2529. [PMID: 27700077 DOI: 10.1021/acs.jnatprod.6b00392] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Oligomers of the 42-mer amyloid-β protein (Aβ42), rather than fibrils, cause synaptic dysfunction in the pathology of Alzheimer's disease (AD). The nucleation phase in a nucleation-dependent aggregation model of Aβ42 is related to the formation of oligomers. Uncaria rhynchophylla is one component of "Yokukansan", a Kampo medicine, which is widely used for treating AD symptoms. Previously, an extract of U. rhynchophylla was found to reduce the aggregation of Aβ42, but its active principles have yet to be identified. In the present work, uncarinic acid C (3) was identified as an inhibitor of Aβ42 aggregation that is present in U. rhynchophylla. Moreover, compound 3 acted as a specific inhibitor of the nucleation phase of Aβ42 aggregation. Compound 3 was synthesized from saponin A (10), an abundant byproduct of rutin purified from Uncaria elliptica. Comprehensive structure-activity studies on 3 suggest that both a C-27 ferulate and a C-28 carboxylic acid group are required for its inhibitory activity. These findings may aid the development of oligomer-specific inhibitors for AD therapy.
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Structure-based design of substituted piperidines as a new class of highly efficacious oral direct Renin inhibitors. ACS Med Chem Lett 2014; 5:787-92. [PMID: 25050166 DOI: 10.1021/ml500137b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Accepted: 04/21/2014] [Indexed: 01/20/2023] Open
Abstract
A cis-configured 3,5-disubstituted piperidine direct renin inhibitor, (syn,rac)-1, was discovered as a high-throughput screening hit from a target-family tailored library. Optimization of both the prime and the nonprime site residues flanking the central piperidine transition-state surrogate resulted in analogues with improved potency and pharmacokinetic (PK) properties, culminating in the identification of the 4-hydroxy-3,5-substituted piperidine 31. This compound showed high in vitro potency toward human renin with excellent off-target selectivity, 60% oral bioavailability in rat, and dose-dependent blood pressure lowering effects in the double-transgenic rat model.
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5
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4-Amino-2-cyanopyrimidines: Novel scaffold for nonpeptidic cathepsin S inhibitors. Bioorg Med Chem Lett 2008; 18:4642-6. [DOI: 10.1016/j.bmcl.2008.07.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Revised: 07/01/2008] [Accepted: 07/05/2008] [Indexed: 11/17/2022]
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6
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Novel scaffold for cathepsin K inhibitors. Bioorg Med Chem Lett 2007; 17:6096-100. [PMID: 17911019 DOI: 10.1016/j.bmcl.2007.09.047] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2007] [Revised: 09/10/2007] [Accepted: 09/12/2007] [Indexed: 11/15/2022]
Abstract
Pyrrolopyrimidine, a novel scaffold, allows to adjust interactions within the S3 subsite of cathepsin K. The core intermediate 10 facilitated the P3 optimization and identified highly potent and selective cathepsin K inhibitors 11-20.
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7
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Synthesis and structure–activity relationship of RXR antagonists based on the diazepinylbenzoic acid structure. Bioorg Med Chem Lett 2007; 17:4808-11. [PMID: 17651969 DOI: 10.1016/j.bmcl.2007.06.079] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Revised: 06/15/2007] [Accepted: 06/18/2007] [Indexed: 11/27/2022]
Abstract
Synthesis and structure-activity relationship of RXR antagonists employing a diazepinylbenzoic acid scaffold are described. Of those antagonists, sulfonamide derivatives (6v and 6w) reveal a high antagonistic activity and good pharmacokinetic properties.
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Synthesis and structure–activity relationship of novel RXR antagonists: Orally active anti-diabetic and anti-obesity agents. Bioorg Med Chem Lett 2007; 17:4804-7. [PMID: 17651968 DOI: 10.1016/j.bmcl.2007.06.080] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Revised: 06/15/2007] [Accepted: 06/18/2007] [Indexed: 11/30/2022]
Abstract
A series of diazepinylbenzoic acid derivatives were synthesized and tested in the inhibition assay of the transactivation of RXR. Oral treatment of cyano derivatives (16f) was found to show anti-diabetic and anti-obesity effects in KK-A(y) mice.
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9
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Laparoscopy-assisted hepatic lobectomy using hilar Glissonean pedicle transection. Surg Endosc 2007; 21:1466-8. [PMID: 17356935 DOI: 10.1007/s00464-007-9253-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2006] [Accepted: 01/25/2007] [Indexed: 02/06/2023]
Abstract
Although many reports have described laparoscopic minor liver resections, major hepatic resection, including right or left lobectomy, has not been widely developed because of technical difficulties. This article describes a new technique for performing laparoscopy-assisted right or left hepatic lobectomy using hilar Glissonean pedicle transection. Laparoscopic mobilization of the right or left hepatic lobe is performed, including dissection of the round, faliciform, triangular, and coronary ligaments. The right or left Glissonean pedicle is encircled and divided laparoscopically. A parenchymal dissection is then performed though the upper median or right subcostal incision, through which the resected liver is removed. We successfully performed this procedure in 6 patients without blood transfusion or serious complications. Laparoscopy-assisted hepatic lobectomy using hilar Glissonean pedicle transection can be feasible and safe in highly selected patients.
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Abstract
Recently, Glut1 (human erythrocyte glucose transporter) expression has been demonstrated in various tumors. The aim of this study is to evaluate the prognostic utility of Glut1 expression in esophageal carcinomas. We studied Glut1 expression by immunohistochemistry of paraffin sections from 63 esophageal squamous cell carcinomas. All 63 carcinomas expressed Glut1. The mean percentage of positively stained tumor cells was 77.8% (median, 84.7%). There were two staining patterns in positive cells: 'strongly positive' and 'weakly positive'. The percentage of 'strongly positive' cells (%Glut1-SP) ranged from 0% to 95.6% (mean, 32.3%; median, 27.4%). The 5-year survival rate for patients with a high %Glut1-SP (> 30%) was significantly lower than that for patients with a low %Glut1-SP (< 30%) (P < 0.01). Statistical analysis revealed that the relative risk of death for patients with high %Glut1-SP was 2.02 times that for patients with low %Glut1-SP (P = 0.064), suggesting a possible independent predictive value for %Glut1-SP.
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11
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[Primary renal non-Hodgkin's lymphoma presenting as immune thrombocytopenia]. [RINSHO KETSUEKI] THE JAPANESE JOURNAL OF CLINICAL HEMATOLOGY 2001; 42:41-6. [PMID: 11235133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
A 25-year-old man was admitted to our hospital because of hematuria, anemia and thrombocytopenia. Laboratory examinations revealed an increased number of bone marrow megakaryocytes and an increased level of platelet-associated immunoglobulin G, suggesting immune thrombocytopenia. Computed tomography of the abdomen showed enlargement of the bilateral kidneys with multiple low-density areas, although neither lymphadenopathy nor hepatosplenomegaly was evident. After amelioration of the thrombocytopenia by prednisolone therapy, open renal biopsy was performed and a diagnosis of diffuse large B-cell non-Hodgkin's lymphoma was made. The patient achieved complete remission after CHOP therapy. This was thought to be a rare case of primary renal non-Hodgkin's lymphoma initially presenting as immune thrombocytopenia, which was treated successfully by chemotherapy.
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Oligonucleosides with a Nucleobase-Including Backbone, Part 4, A Convergent Synthesis of Ethynediyl-Linked Adenosine Tetramers. Helv Chim Acta 2000. [DOI: 10.1002/1522-2675(20001220)83:12<3229::aid-hlca3229>3.0.co;2-s] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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14
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A method for measuring specific IgE in sera by direct ELISA without interference by IgG competition or IgG autoantibodies to IgE. Int Arch Allergy Immunol 2000; 122:264-9. [PMID: 10971117 DOI: 10.1159/000024408] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND In measuring specific IgE levels in sera by direct ELISA, competition with coexisting IgG often impedes an exact IgE determination; additionally, IgG autoantibodies to IgE (IgG-IgE) in sera affect the assay. In this paper, we attempt to determine accurate specific IgE levels by selective removal of IgG with a protein G-immobilized gel (PG) and by acid treatment of the PG to compensate for the unintended removal of IgE, probably due to the PG binding IgG-IgE. METHODS IgG in sera was removed using PG at pH 7.0. Then, the PG was treated with citrate buffer at pH 3.0 for 5 min to liberate IgE from IgG-IgE complexes, after IgG-binding sites on the PG were saturated with bovine IgG, since PG came to bind IgE at acidic pHs. IgE levels were then measured by ELISA. RESULTS The PG treatment of sera removed the effect of inhibitory competition by coexisting IgG, especially at higher concentrations of sera, to improve specific IgE detection by direct ELISA. However, PG treatment alone sometimes reduced IgE levels (39% of sera tested), even though PG does not bind IgE at pH 7.0, which indicated the presence of IgG-IgE complexes. The reduction in IgE returned almost to their original levels in the sera by acid treatment of the PG. By combining the PG treatment with acid treatment, specific IgE measurement in sera was improved significantly (p < 0.01, Wilcoxon signed rank test). CONCLUSION Measurement of specific IgE in sera by direct ELISA was improved by using the PG and acid treatment technique.
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Oligonucleosides with a Nucleobase-Including Backbone, Part 2, Synthesis and Structure Determination of Adenosine-Derived Monomers. Helv Chim Acta 2000. [DOI: 10.1002/1522-2675(20000705)83:7<1331::aid-hlca1331>3.0.co;2-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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17
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Abstract
Mercury contamination is a serious environmental problem worldwide. Two primary sources of contamination are dumping of large quantities of inorganic mercury and exposure in the mining industry. Although the actual fatal level of mercury vapor is not known, exposure to more than 1-2 mg/m3 of elemental mercury vapor (Hg0) for a few hours causes acute chemical bronchiolitis and pneumonitis. Two hours after exposure, lung injury appears as hyaline membrane formation, and finally, extensive pulmonary fibrosis occurs. Clinical findings correlate with the duration of exposure, the concentration of mercury, and the survival time after exposure. There is no correlation between pathological findings and the concentration of mercury in the tissues. Necrosis of proximal convoluted tubules may be attributed to the disruption of the enzyme systems of Hg2+-sulfhydryl compounds. Metallothionein protein (MT), induced by the accumulation of Hg2+ in the kidneys, may play an important role in detoxication after it forms a non-toxic Hg2+-MT compound. Despite the deposition of mercury in the brain, compared with organic mercury, inorganic mercury did not seem to damage the neurons. Drugs such as chelating agents and corticosteroids appear to effectively decrease the inflammation and delay pulmonary fibrosis.
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Abstract
A YAP scintillator (YAlO3: Ce crystal) for alpha counting has been produced in powder form and this paper describes its performance characteristics. By measuring pulse-height and rise-time distributions, it was found that the YAP powder, as a fast detector for alpha rays, could clearly distinguish alpha events from beta and gamma events. In addition, the YAP powder was used in a phoswich detector combined with a YAG (Y3Al5O12: Ce) crystal for beta and gamma detection.
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Semen specific gamma-glutamyltransferase carries ABH antigens: a sandwich ELISA for simultaneous semen detection and its ABO blood typing. Clin Chim Acta 1999; 283:183-94. [PMID: 10404742 DOI: 10.1016/s0009-8981(99)00052-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Semen type of gamma-glutamyltransferase (gamma-GTP) is different from the membrane bound type of the enzyme in both biochemical and immunological properties, and consists of two subunits (150 and 95 kDa). We found that anti-ABH antibodies recognize a 150-kDa subunit of seminal gamma-GTP by Western blot and immunoprecipitation analyses. Using SG2, one of anti-semen specific gamma-GTP monoclonal antibodies which we had produced, and anti-ABH antibodies, we established a sandwich ELISA for identifying human seminal gamma-GTP and its ABO type simultaneously. This sandwich ELISA allows ABO typing of highly diluted semen. The dilutions for ABO typing were 10(5) times for A or O, and 10(4) times for B. Furthermore, ABO typing of semen was successfully performed by this ELISA, even in the mixed presence of vaginal fluid, saliva and blood. Thus, seminal gamma-GTP carries ABH antigens and the sandwich ELISA with SG2 and anti-ABH antibodies enables ABO typing of semen. The sandwich ELISA is extremely useful for ABO typing originated from semen in the mixture of biological fluids.
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Reconstruction of defects of the entire vermilion with a buccal musculomucosal flap following resection of malignant tumors of the lower lip. Plast Reconstr Surg 1997; 100:422-30. [PMID: 9252611 DOI: 10.1097/00006534-199708000-00024] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We reconstructed a defect of nearly the entire lower vermilion using a buccal musculomucosal flap following resection of a malignant tumor of the lower lip and obtained satisfactory results. The buccal musculomucosal flap was semi-spindle shaped and pedicled at the angle of the mouth. A flap measuring as much as 1.5 cm in width and 5 cm in length could be raised while ensuring that fibers of the buccinator muscle extended over its entire length. Using this technique, it was possible to reconstruct a wide defect following tumor resection and removal of almost the entire lower vermilion by means of only a transposition of a unilateral buccal musculomucosal flap after about one-quarter of the lower lip had been excised and sutured primarily. Reconstruction with this technique is a two-stage operation, and a secondary minor touch-up operation is performed on the angle of the mouth at the same time as repair of the dog-ear of the pedicle. Advantages of this technique are that food can be taken orally soon after the operation, hemodynamics in the flap are maintained stably because the flap contains fibers of the buccinator muscle, and the vermilion is given a natural eminence. In addition, postoperative drooling is minimized, and sensation returns to the vermilion within the early postoperative period. Based on these advantages, we think our technique should be the first choice for carrying out reconstruction of defects that are located mainly in the lower lip vermilion because this is a safe and reliable method with which we performed 12 cases of vermilion reconstruction without flap necrosis and with satisfactory aesthetic and functional results.
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21
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Effects of prostaglandin E1 on cultured dermal fibroblasts from normal and hypertrophic scarred skin. J Dermatol Sci 1997; 14:217-24. [PMID: 9138479 DOI: 10.1016/s0923-1811(96)00577-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
To investigate the role of prostaglandin (PG) E1 in preventing scar formation as well as that of the related cytokines, we culture fibroblasts from hypertrophic scar tissue (SDF) and normal dermis (NDF) collected from patients with scar contracture. We have compared the type I collagen synthesis, type I collagenase activity, and the production of interleukin (IL)-6, IL-8 and transforming growth factor (TGF)-beta(1) in two types of cultured fibroblasts before and after addition of PGE1. Our results demonstrated that levels of type I collagen and TGF-beta(1) production were higher and that type I collagenase activity and IL-8 production were significantly lower in the culture supernatants of SDF. There was no significance difference in IL-6 production between SDF and NDF culture supernatants. On the other hand, PGE1 significantly increased type I collagenase activity and IL-8 production in the SDF culture supernatants and it increased IL-6 and TGF-beta(1) production in both types of fibroblasts. However, there was no effect on synthesis of type I collagen in either group. To further investigate the role of TGF-beta(1) in NDF and SDF, exogenous recombinant human (rh) TGF-beta(1) was added. In NDF group, rhTGF-beta(1) induced a decrease in the type I collagenase/type I collagen ratio, while rhTGF-beta(1) had no effect on the same ratio in the SDF group. These results suggest that PGE1 may have a role in the prevention of hypertrophic scar by increasing the activity of type I collagenase.
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22
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Total synthesis of MS-444, a myosin light chain kinase inhibitor. J Antibiot (Tokyo) 1997; 50:289-90. [PMID: 9127208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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23
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The Total Synthesis of a Glycosidase Inhibitor, Nagstatin. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1997. [DOI: 10.1246/bcsj.70.427] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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24
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Reconstruction of deep ulcer by free groin flap transfer. Ann Plast Surg 1997; 38:86-7. [PMID: 9015555 DOI: 10.1097/00000637-199701000-00025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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25
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Primary maxillary reconstruction after radical maxillectomy using a combined free flap and secondary dynamic suspension. J Craniofac Surg 1997; 8:65-73; discussion 74. [PMID: 10332302 DOI: 10.1097/00001665-199701000-00020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
We report a case of maxillary reconstruction aimed at optimizing facial contour, oral function, and facial animation after radical maxillectomy. In the first stage, using combined latissimus dorsi serratus anterior flaps attached with ribs, we performed a three-dimensional restoration for midface defects. In the second stage, we performed dynamic reconstruction of the nasolabial fold and upper lip using a temporal muscle transposition. As a result, the upper lip was able to be elevated as much as 10 mm when the patient clenched his teeth, and the outcome was judged to be both aesthetically and functionally satisfactory.
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26
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Abstract
We devised an operation to correct Stahl's ear, a rare but difficult to treat auricular malformation. First, a wedge excision is made of the anterior skin and cartilage of the abnormal, third crus prominence. The abnormal, flat part of the helix is excised. A conchal cartilage graft is used to support the area after closure of the defect, including advancement of the helical edges. The procedure has been used in five cases with satisfactory results.
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Effects of cytokines in burn blister fluids on fibroblast proliferation and their inhibition with the use of neutralizing antibodies. Wound Repair Regen 1996; 4:426-32. [PMID: 17309693 DOI: 10.1046/j.1524-475x.1996.40406.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Recent studies have shown that tissue exudates, such as burn blister fluid and donor site wound fluid, have promotive effects on wound healing. In the present study, results obtained with enzyme-linked immunosorbent assays showed that at least three cytokines, transforming growth factor-beta1, transforming growth factor-alpha, and interleukin-6, exist at high concentrations in burn blister fluids. It was also found that these exudates were able to greatly enhance the rate of human fibroblast proliferation. However, neutralizing antibodies to transforming growth factor-beta1, transforming growth factor-alpha, interleukin-6, and platelet-derived growth factor failed to prevent this proliferative effect. Ultrafiltration of the exudates showed these cytokines to be in the high molecular weight fractions (30 to 300 kDa and >300 kDa) and that these fractions retained mitogenic activity toward fibroblasts. Therefore it was postulated that the cytokines were bound to high molecular weight substances such as serum proteins in these exudates and could escape neutralization by antibodies directed against them.
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Abstract
This report discusses the effectiveness of conservative treatment of burns using applications of prostaglandin E1 (PGE1) containing ointment (PGE1 ointment) to the wound site. Fourteen patients with superficial dermal burns (SDB), deep dermal burns (DDB) and full-thickness dermal burns (DB), who were treated with repeated applications of this ointment, showed rapid epithelialization of the affected tissue. Hypertrophic scarring after epithelialization was less than that expected after other therapies. The degree of scarring was graded as 'none', 'mild', 'moderate' or 'severe'. The results of this therapy revealed no scarring in two sites (8.7 per cent), mild scarring in 16 sites (69.6 per cent), moderate scarring in one site (4.3 per cent) and severe scarring in four sites (17.4 per cent) out of 23 sites distributed among the patients. The application of PGE1 ointment in combination with skin grafting surgery was found to improve functional and aesthetic results in the patients with DDB and DB, by minimizing the area of the donor site; it was especially useful for children with extensive burns because of the shortage of available tissue as donor site material for skin grafting.
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Abstract
A sandwich enzyme-linked immunosorbent assay (ELISA) was developed for detecting human seminal gamma-glutamyl transpeptidase (gamma-GTP) using a combination of anti-seminal gamma-GTP monoclonal antibodies. These monoclonal antibodies did not react with human ovary or uterus in immunohistochemical study. Optimal assay condition, resulting in a sensitive assay with a low background, is presented. The detection limit of this assay was estimated to be 1 ng/ml of seminal gamma-GTP corresponding to about 100,000 times dilution of seminal sample. This ELISA was specific for seminal gamma-GTP, without cross-reactivity to renal or hepatic gamma-GTP, normal blood serum, non-coital vaginal fluid or saliva. The recovery of seminal gamma-GTP added to various biological fluids were also examined.
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30
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Abstract
This study was performed to evaluate cytokines in donor-site wound fluids and to determine their effect on wound healing. A film dressing was applied to the donor-site wound of 24 patients immediately after a split-thickness skin graft was taken. On the 5th day after treatment, 2-3 ml of the fluid retained under the film dressing was collected by means of puncture with a syringe. Growth factors and cytokines considered to accelerate wound healing were present in relatively large amounts in the exudate. Very low concentrations of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) were detected by a commercially-available enzyme-linked immunosorbant assay (ELISA) kit. However, the presence of both growth factors in wound fluid could not be confirmed because of the possible cross-reactivity of the antibodies to other EGF and FGF family growth factors. In contrast, platelet derived growth factor (PDGF), interleukin-6 (IL-6), transforming growth factor-alpha (TGF-alpha) and TGF-beta were present in relatively large amounts. The finding that certain cytokines coexist in a balanced state under the film dressing suggests that epithelization can proceed, since an adequate balance would insure proper regulation by the cytokine network. Our present study increases the likelihood that film or hydrocolloid dressings will be used more frequently in the future for treatment of burn wounds, ulcers or donor-site wounds since these dressings were shown to be more capable than ointments of retaining cytokines, particularly intrinsic growth factors secreted at the wound site.
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31
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Pneumocephalus caused by fistulas of the mastoid air cells treated with a temporoparietal fascial flap. J Craniofac Surg 1995; 6:494-8. [PMID: 9020741 DOI: 10.1097/00001665-199511000-00016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Using a temporoparietal fascial flap and hydroxyapatite ceramics, we treated a patient for complications after a neurosurgical operation for glossopharyngeal neuralgia. These consisted of pneumocephalus and cerebrospinal fluid rhinorrhea resulting from fistulas of mastoid air cells associated with a subcutaneous dead space. By means of the temporoparietal fascial flap, we were able to fill the dead space and reinforce the repaired dural and mastoid lesion as well. Hydroxyapatite ceramics were also useful for closing the mastoid air cell fistulas.
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32
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Abstract
Results following surgical treatment for cryptotia are as yet far from fully satisfactory in cases in which deformity of the upper auricular portion is severe and particularly when there is contraction of the helical skin and auricular cartilage. Therefore, improvements in operative procedures have been considered necessary. We have developed a new method for treating cryptotia using a rhomboid flap in the superior and anterior auricular regions to correct the contraction of skin in the helix in cases in which the deformity of the upper auricular portion is large and shortening in the anterior and posterior directions is significant and in which severe contraction of the helix is observed. In this report, we describe the operative procedures used and present the relatively favorable results obtained in three patients. Using these techniques, we have been able to elongate the contracted helix frequently observed in cases of cryptotia by preparing a flap in the anterior auricular region. This approach appears to be a useful and safe means of treating cryptotia and so-called constricted ear as well.
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Abstract
This report indicates that retention fluid from blisters of partial skin thickness burns, which contains relatively large amounts of cytokines and growth factors, stimulates the wound healing process. Although epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) levels were low, relatively large amounts of cytokines including platelet derived growth factor (PDGF), interleukin (IL-6) and transforming growth factor (TGF) alpha were present and these exercised stimulatory effects on wound healing. TGF beta, which plays an important role in collagen metabolism and in scar formation, was also detected. Contrary to our expectations, IL-1 alpha and beta, both of which initiate inflammation, were detected at relatively low levels whereas IL-8 levels were rather high. Various cytokines were shown to coexist in a balanced state in the retention fluids, suggesting that epithelialization might be regulated via a cytokine network operating on the wound surface. The growth of keratinocytes in culture significantly increased with the addition of 1 per cent or more of blister fluid to the medium.
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Bone induction of hydroxyapatite combined with bone morphogenetic protein and covered with periosteum. Plast Reconstr Surg 1995; 95:1265-72. [PMID: 7761515 DOI: 10.1097/00006534-199506000-00019] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Using a rabbit model, we evaluated the role of the periosteum in bone induction using hydroxyapatite ceramic pellets, some of which had been coated with bone morphogenetic protein. Eighteen rabbits were divided into two groups, a control group that received pellets soaked in phosphate-buffered saline alone and another group for which the pellets had been supplemented with bone morphogenetic protein. After making a skin incision on the head of each rabbit, two caudally pedicled periosteal flaps measuring 1 cm in width and 2.5 cm in length were elevated. These flaps were wrapped around hydroxyapatite pellets manufactured from limestone and fixed with sutures. After implantation, both groups of rabbits were returned to their cages, maintained for 3, 6, or 9 weeks [every group consisted of 3 rabbits (6 pellets)], and then sacrificed. In this study, the extent of bone induction, which was measured with a dual x-ray densitometer, that resulted from covering the hydroxyapatite pellet with periosteum alone (control group) was minimal. On the contrary, since osteogenesis from the periosteum toward the pores of the pellet was observed in the bone morphogenetic protein group much more than in the control group, the usefulness of our technique was confirmed. However, active osteogenesis was observed with subperiosteal implantation of the hydroxyapatite-bone morphogenetic protein complex in the bone morphogenetic protein group, but the osteogenesis observed was not distributed over the entire pellet.
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Efficacy of hydroxyapatite ceramic as a carrier for recombinant human bone morphogenetic protein. J Craniofac Surg 1995; 6:238-44. [PMID: 9020695 DOI: 10.1097/00001665-199505000-00011] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
In this study, we investigated the efficacy of hydroxyapatite ceramic (HAP) as a carrier of bone morphogenetic protein (BMP) using porous HAP pellets artificially fabricated from limestone. After treatment with recombinant human BMP-2, the pellets were inserted beneath the cranial periosteum of rabbits, and the degree of osteogenesis was examined histologically. The degree of osteogenesis was also evaluated using image-analyzing procedures. Results showed that extensive bone formation had occurred around the pellets 3 weeks after insertion in the group that received pellets treated with recombinant human BMP alone as well as in the group that received recombinant human BMP in addition to type I collagen-treated HAP pellets. Subsequently, osteogenesis within the pellets slowly progressed over time, and by 9 weeks after insertion most of the pellet pores in both groups were filled with newly generated bone. The recombinant human BMP-collagen group, however, exhibited a significantly greater bone induction. These results indicated that if recombinant human BMP is used clinically in the future, artificially fabricated HAP would be a suitable carrier.
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Comparison of kinetic property between human seminal and renal gamma-glutamyltransferase. Fukushima J Med Sci 1994; 40:119-32. [PMID: 7642163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The initial-velocity kinetics, optimal pH, acceptor specificity and the influence of metal ions, EDTA and urea were studied on the human seminal gamma-glytamyltransferase (GGT) in comparison with the human renal GGT. The activity was measured with glycylglycine as an acceptor and with gamma-glutamyl-4-nitroanilide or gamma-glutamyl-3-carboxy-4-nitroanilide as a donor. Because the double-reciprocal plots showed paralled lines, the reaction of seminal GGT proceeds in nonsequence (Ping Pong Bi Bi) mechanism. The acceptor Michaelis constants for the seminal GGT were about 2 times higher than those for the renal enzyme with gamma-glutamyl-3-carboxy-4-nitroanilide as well as gamma-glutamyl-4-nitroanilide as donors, which the donor michaelis constants for seminal GGT were very similar to those for renal enzyme. The optimal pH and pK values were 8.2-8.6 and about 7.7, respectively. There was little difference in the specificity for various acceptors between the seminal and renal enzyme. Glycylglycylglycine was an effective acceptor other than glycylglycine, showing 80% of the activity with glycylgycine. Various substrates including metal ions tested were practically neither inhibitory nor stimulatory for seminal and renal GGTs.
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Evaluation of cytokines in donor site wound fluids. SCANDINAVIAN JOURNAL OF PLASTIC AND RECONSTRUCTIVE SURGERY AND HAND SURGERY 1994; 28:269-73. [PMID: 7899836 DOI: 10.3109/02844319409022010] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The aim of the study was to measure concentrations of cytokines in wound fluid from donor sites. A film dressing was applied to the donor sites (mean size 10 x 15 cm) immediately after a split skin graft had been taken. Five days later the film was punctured with a needle and 2-3 ml of the fluid accumulated under the film dressing was withdrawn into a syringe. The fluid was snap frozen and stored immediately at -70 degrees C. The fluid was examined for epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), transforming growth factor (TGF) alpha, TGF beta, interleukin (IL)-1 alpha and IL-1 beta. The results showed that the fluid accumulated under the film dressing contained growth factors and cytokines that are thought to promote healing. The fluid was rich in TGF alpha but contained no EGF or bFGF, which indicates that TGF alpha plays a major part for promoting local wound healing.
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Orbital reconstruction with hydroxyapatite ceramic implants. SCANDINAVIAN JOURNAL OF PLASTIC AND RECONSTRUCTIVE SURGERY AND HAND SURGERY 1994; 28:193-8. [PMID: 7831549 DOI: 10.3109/02844319409015980] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Thirteen patients with fractures of the orbital floor (inferior wall), medial and lateral walls, or so-called "blowout" fractures with or without fractures of the zygoma were treated with artificially made hydroxyapatite ceramic implants made entirely from limestone, some of which were made with computer aided design and computer aided machinery (CAD-CAM) from data obtained from helical computed tomography. Orbital reconstruction with hydroxyapatite ceramic implants is a safe technique which is superior to previous ones in which autogenous or plastic materials were used.
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40
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Immunocytochemical study of seminal gamma-glutamyltransferase using monoclonal antibodies. Cell Tissue Res 1994; 277:33-8. [PMID: 7914473 DOI: 10.1007/bf00303078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We produced three monoclonal antibodies, SG1, SG2 and SG3, specific for human seminal gamma-glutamyltransferase when characterized by enzyme-linked immunosorbent assay and immunoblotting. Seminal gamma-glutamyltransferase was localized, by immunostaining, to the epithelial cells of the ductus epididymidis, seminal vesicle and prostate gland with SG1, those of the prostate gland with SG2, and those of the seminal vesicle with SG3. Rabbit polyclonal anti-seminal gamma-glutamyltransferase serum reacted with the proximal convolution of the kidney and the bile capillaries of the liver, and with the epithelial cells of the reproductive organs. However, immunoreactivity was not observed in the kidney or liver with the monoclonal antibodies. Thus, these monoclonal antibodies are probably all specific to seminal gamma-glutamyltransferase but recognize different epitopes.
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Abstract
Helical volume scan computed tomography is a recently developed technology by means of which detailed data for most facial bone areas can be accumulated in a very short period, i.e., about 30 seconds, a much shorter time than required with conventional computed tomography. From a clinical standpoint, this is extremely important. In this report we discuss the principles of a method for preparing actual-size models by laser lithographic procedures based on data obtained by helical volume scan computed tomography. With these procedures, it is possible to obtain a good reproduction with high accuracy, on the order of 0.5 mm, not only of the outer morphologic structure of the cranial and maxillofacial bones but also of portions of the inner structure of cavities such as the cranium and paranasal sinuses. The difference between the original and model was under 3 percent, as confirmed by constructing a model of the dry skull with helical volume scan computed tomography. Therefore, production of exact-size models using helical volume scan computed tomography data represents an important technological development, breaking through previous limits imposed by conventional simulations prepared with three-dimensional images using CRT. With the combined use of laser lithographics and helical volume scan computed tomography, operative methods for craniomaxillofacial surgery should improve significantly in the near future.
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Practical Preparation of (Z)-2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-methoxyiminoacetic Acid: A Side-Chain of the Fourth Generation of Cephem Antibiotics. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1994. [DOI: 10.1246/bcsj.67.1701] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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43
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Abstract
Cilostazol (Cls) is a inhibitor of phosphodiesterase and increases cyclic AMP (cAMP) in platelets and also raises the vascular smooth muscle cell cAMP level causing vasodilation. Therefore, it was expected to increase local blood flow in the skin. Topical application of Cls may improve local blood flow without systemic effects in clinical situations. In this paper the effect of Cls lotion on skin blood flow was assessed in animal experiments. Application of this lotion allowed skin blood flow to remain at increased levels for about 60-90 min. Tissue assay of the Cls content revealed that Cls is absorbed percutaneously and retained, even in the inner tissue layer, for at least 180 min.
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A practical preparation of (Z)-2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(methoxyimino)acetic acid. Tetrahedron Lett 1993. [DOI: 10.1016/0040-4039(93)85061-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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45
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Treatment of extensive cranial bone defects using computer-designed hydroxyapatite ceramics and periosteal flaps. Plast Reconstr Surg 1993; 92:819-30. [PMID: 8415963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We performed cranioplasty using hydroxyapatite ceramics and periosteal flaps in three patients with extensive cranial bone defects. These defects were left after post-brain surgery infection forced the removal of cranial bone. Hydroxyapatite ceramics made by using computer-aided design from three-dimensional computed tomographic image data were implanted in these patients. The defects were relatively large (the largest was 16.5 x 7.5 cm) and had a high degree of curvature. Three pieces were required in one patient, although one piece was sufficient in the other two patients. The surgical technique consisted of removal of the epidural granulation tissue, exposure of the cranial bone defect site, and shaping of the hydroxyapatite ceramics to fit the defect entirely, followed by the implantation of the hydroxyapatite ceramics. In anticipation of induction of the bone to hydroxyapatite, we covered the hydroxyapatite ceramics with periosteal flaps of cranial bones; however, based on only these three patients, our knowledge of the ossification-promoting effect is incomplete. More clinical cases should be investigated to evaluate further the clinical efficacy of this method for treatment. As we have reported here, the treatment of cranial bone defects by using computer-designed hydroxyapatite ceramics and a periosteal flap is safe and highly effective.
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A method of treatment of constricted ears with a conchal cartilage graft to the posterior auricular plane. Plast Reconstr Surg 1993; 92:621-7. [PMID: 8356124 DOI: 10.1097/00006534-199309001-00010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In order to make natural auricular features in a simple and certain way and also to prevent the occurrence of a postoperative lop-eared deformity, we contrived a new method to treat constricted ears. Our method consists of correction of the anthelical deformity according to a modified Converse method and a cartilage graft harvested from the posterior region of the concha to fix as a support on the posterior auricular plane which enables the auricle to maintain a normal shape. This method resulted in very satisfactory treatment of prominent ears or ears with mild helical constriction, categorized as group I, IIa, or IIb on Tanzer's classification, and the patients did not have marked postoperative problems. Thus, in this respect, our technique is considered to be a very effective and safe method.
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Abstract
A dermis slicer designed by the authors enabled us to prepare about 10 sheets of sliced dermal grafts (SDG), 300 micron(s) thick, from the dermis harvested from the back or buttocks of adult patients during operations. Such a sliced dermal sheet was stretched with one surface stuck on the base of a culture dish. It was then incubated in Dulbecco's essential medium for tissue culture, to which epidermal growth factor had been added. By the first week only its upper side was epithelialized from epithelial components in sliced dermis. The formation of basement membrane with anchoring fibrils was confirmed by electron microscopy. The appearance of type IV collagen and laminin was observed between epithelialized basal cells and the dermal layer. Thus, it is thought that the SDG is useful not only for immediate grafting, when epithelialization follows, but also as a substitute for free split thickness skin grafts following tissue culture.
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48
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Abstract
Deep dermal burns covering 30 per cent of the total body surface area were prepared by immersing the backs of rabbits in hot water at 80 degrees C for 20 s, to determine whether platelet activating factor (PAF) was involved in the onset of oedema following burns and to evaluate the effect of TCV-309, a potent PAF antagonist. The PAF antagonist, which was infused soon after the burn, blocked oedema formation in the wound and significantly (P < 0.001) inhibited PAF increase (P < 0.05) in the damaged tissue in a dose-dependent manner. This was confirmed by immunohistochemistry. In contrast, the superoxide dismutase content in the group treated with a high dose of TCV-309 was significantly (P < 0.01) higher than that of the control group. These findings suggest that administration of large doses of a PAF antagonist immediately after injury prevents oedema of burn wounds and the subsequent onset of burn shock by suppressing PAF and superoxide radical formation.
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49
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Abstract
Reconstruction with the oblique sigmoid island flap, which we contrived as a subcutaneous pedicle flap, is performed as follows: the small triangular skin flaps, about 1 to 2 mm in length on each side, are excised from both sides of a round defect following tumor excision in a direction corresponding to the wrinkle line, and a subcutaneous island flap which has a width equal to the defect and has shifted about half the distance of the defective area in parallel with the wrinkle line is advanced and sutured. Our technique is thought to be highly effective from a cosmetic point of view because reconstruction of the defects following excision of small tumors that occur in sites with delicate eminence, such as the area between the inner canthal region and the cheek, the site along the nasolabial fold, and around the alae, often tends to fail to achieve cosmetically good results when conventional local skin flaps are used.
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Substrate specificity of 6-deoxyerythronolide B hydroxylase, a bacterial cytochrome P450 of erythromycin A biosynthesis. Biochemistry 1993; 32:1905-13. [PMID: 8448148 DOI: 10.1021/bi00059a004] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The 6-deoxyerythronolide B hydroxylase (EryF) is a soluble cytochrome P450 responsible for the stereospecific C-6 hydroxylation of the erythromycin precursor, 6-deoxyerythronolide B. Using the expression of the eryF gene in Escherichia coli [Andersen, J. F., & Hutchinson, C. R. (1992) J. Bacteriol. 174, 725-735] as the enzyme source, we examined the catalytic activity of the EryF protein toward several macrolide substrates related to 6-deoxyerythronolide B. The results of these studies were compared with measurements of the apparent dissociation constants for various substrates and with information from molecular modeling studies of the substrates and the enzyme-substrate complex. Only minor changes in the structure of 6-deoxyerythronolide B resulted in substrates with catalytic rates less than 1% of those seen with the natural substrate. Although the 9S epimer of 9-deoxo-9-hydroxy-6-deoxyerythronolide B was hydroxylated at a rate approximately equal to the natural substrate, the 9R epimer was hydroxylated at a 2-fold lower rate. Examination of molecular models revealed that the position of the 9-hydroxyl oxygen in the 9S epimer resembles that of the 9-oxo oxygen in the natural substrate more closely than in the 9R epimer. 8,8a-Deoxyoleandolide, which is identical to 6-deoxyerythronolide B except for the presence of a C-13 methyl group, and its (9S)-9-deoxo-9-hydroxy derivative were C-6 hydroxylated at a 4-fold lower rate than the natural substrate, and the 9-oxo form showed a substantially larger apparent dissociation constant.(ABSTRACT TRUNCATED AT 250 WORDS)
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