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51.
52.
Su CH Liu SH Yu SY Hsieh YL Ho HO Hu CH Sheu MT 《Journal of biomedical materials research. Part A》2005,72(2):220-227
SACCHACHITIN membranes, prepared from the waste residue of the fruiting body of Ganoderma taugae, were used in our previous study to enhance skin wound healing in animal models. In the present study, the effects of the membrane on the growth of keratinocytes and the activity of matrix metalloproteinases (MMPs), as well as on the healing of skin wounds in humans, were estimated. Fresh human foreskin was employed as the source of the keratinocyte culture, and a modified keratinocyte-SFM medium supplemented with 0.2 ng/mL of recombinant epidermal growth factor and 30 microg/mL bovine pituitary extract was used to enhance the successful growth of keratinocytes under an atmosphere of 5% CO2, at 37 degrees C. The results indicated that 0.01% SACCHACHITIN enhanced the proliferation of keratinocytes in the culture on the fourth and fifth days, and cells showed neither morphological alteration nor disordered proliferation. This evidence clearly indicated that SACCHACHITIN was not cytotoxic to and was safe for the growth of keratinocytes. Thus, SACCHACHITIN might play a positive role in the proliferation and differentiation of keratinocytes around wounds and in accelerated wound healing of epidermal tissue. In addition, microscopic observations during the growth of keratinocytes showed that normal proliferation and differentiation took place along the margin of the SACCHACHITIN membrane. This indicates that SACCHACHITIN is possibly cytocompatible with keratinocytes. Electrophoretic analysis and inhibition tests for the binding effect of SACCHACHITIN on MMPs showed that SACCHACHITIN reduced MMPs in extracellular matrix degradation and facilitated establishment of an extracellular matrix around wounds; these effects resulted in rapid wound healing. SACCHACHITIN was used as a skin dressing for patients who had skin chronicle ulcer, which had not healed for over 7 months. Preliminary clinical observations showed that the wound improved and began to heal. An analysis of MMPs by ELISA in tissue of the wound indicated a significant decrease in MMP levels. 相似文献
53.
54.
Wang SW Hsieh SC Ding MJ 《Zhonghua Minguo wei sheng wu ji mian yi xue za zhi = Chinese journal of microbiology and immunology》1997,30(3):160-169
A DNA amplification system using the polymerase chain reaction (PCR) combined with a nonradioactive digoxigenin-labeled probe hybridization was employed to detect Mycobacterium tuberculosis in clinical specimens. One hundred and thirty specimens were tested by several methods including routine culture method, acid-fast staining, BACTEC 460 detection system, PCR, and PCR-hybridization techniques. Sixteen out of 130 specimens were culture positive on Middlebrook 7H11 agar, 10 were positive with acid-fast staining, 18 were positive with BACTEC 460 detection system, 23 were positive with PCR technique, and 62 were positive with PCR-nonradioactive hybridization technique. When compared with culture results, PCR-nonradioactive hybridization had an overall sensitivity of 100% (16/16) and a specificity of 59.7% (68/114). However, 28 out of 46 (60.9%) PCR-nonradioactive hybridization positive specimens which were culture negative had clinical data supporting the diagnosis of tuberculosis. In addition, 4 specimens which were negative by routine culture but positive by BACTEC 460 detection system and two specimens which were negative by routine culture but positive by acid-fast staining were all positive by PCR-hybridization technique. These data suggest that routine culture method may not be sensitive enough to detect M. tuberculosis in all kinds of clinical specimens. Taking this deviation into account, the specificity of PCR-nonradioactive hybridization technique may be rectified range from 63% (68/108) to 79.1% (68/86). PCR itself is not satisfactory enough to detect M. tuberculosis in specimens (the sensitivity and specificity were 56.3% and 87.7%, respectively) in this study. However, when it combines with DNA hybridization technique, they can be a very powerful and rapid diagnostic tool to detect M. tuberculosis in clinical specimens. 相似文献
55.
56.
Michael J. Keherly Ching-Chyuan Hsieh Jerome L. McCombs Linda S. Merryman John Papaconstantinou 《Somatic Cell and Molecular Genetics》1996,22(2):119-134
We utilized an AFP-HPRT transgene, i.e. the HPRT coding sequences under the regulation of AFP enhancer and promoter sequences,
to localize the AFP extinguisher locus in intertypic somatic cell hybrids (hepatoma X fibroblast). This hybrid gene construct,
which directly links AFP regulation to a reversibly selective gene, enabled the selection of stably transfected cells which
express AFP, as well as cells showing extinction of AFP. Mouse hepatoma cells stably transfected with and expressing the transgene
were fused to human fibroblasts, and the resulting somatic cell hybrids were characterized using Southern, Northern and karyotypic
analyses. That several hybrids exhibited the proper extinction of AFP, AFP-HPRT and albumin suggests coregulation of these
genes by an extinguisher. Segregant lines derived from these hybrids were selected for the loss of extinguisher activity and
for reexpression of the transgene. Karyotypic analysis of hybrid and segregant lines, exhibiting proper AFP, albumin and AFP-HPRT
phenotypes, revealed that the presence of human chromosome 7 was most closely associated with the AFP-extinguished state.
The hybrids generated in these studies now make it possible to isolate the sequences responsible for AFP and albumin extinction. 相似文献
57.
A Takemura H Okuda K Oda Y R Fang H M Hsieh Y Ohta 《Kaibogaku zasshi. Journal of anatomy》1990,65(5):374-380
An anomalous case of the right subclavian artery arising from the aortic arch as the last branch, in which the first branch was the right common carotid, the second the left common carotid and the third the left subclavian artery, was found in a 10 months human fetus among 173 fetuses. The right subclavian artery arose from the posterior wall of the aortic arch at the level of the Th4 and passed obliquely between the esophagus and the thoracic vertebrae. The right and the left vertebral arteries arising from the subclavian arteries on the same side entered the transverse foramen of the C6 of each side. This case belonged to type G of Adachi's classification and as well type 5 of Holzapfel's. The present authors wish to offer a new trial classification on these variations, including the origins and numbers of the vertebral arteries, by investigating many original reports in Japanese, as follows: 1) A new classification is fixed on the basis of the type G and H of Adachi-Williams et al.-Nakagawa in the classification of the branching types of the aortic arch. The type G represents that the right common carotid, the left common carotid, the left subclavian and the right subclavian arteries arise from the aortic arch in this order. The type H represents that the bicarotid trunk, the left subclavian and the right subclavian arteries arise from the aortic arch. 2) When the left vertebral artery arising from the aortic arch is found in the type G and H, "C" is prefixed G or H, as type CG, type CH. 3) When the right vertebral artery arising from the right common carotid artery is found, a prime mark, "', is put on G or H, as type G', type H'. 4) In order to represent a compound type of the above 2) and 3), both "C" and "' are put, as type CG', type CH'. 5) When the bilateral vertebral arteries arising from the respective subclavian artery are found in the above 2), 3) and 4) "2" postfixed "C" and the prime mark "', as type G'2, type C2G, type CG'2, type C2G', type C2G'2, type H'2, type C2H, type CH'2, type C2H', type C2H'2. According to the above new classification, Adachi's type G can be arranged into 18 branching types. This classification may be helpful and sufficient to provide more than 100 cases of the type G and H reported on Japanese.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
58.
Beta-thalassemia is a common inherited disease, resulting from one or more of a total of more than 200 different mutations in the beta-globin gene (HBB). Efficient and reliable mutation-screening methods are essential in order to establish appropriate prevention programs for at-risk populations based upon a molecular diagnosis. We have developed a rapid and highly-specific mutation screening test for the diagnosis of beta-thalassemia by coupling heteroduplex and primer-extension analysis based on the denaturing high performance liquid chromatography (DHPLC) system. A total of 161 healthy heterozygous Taiwanese carriers featuring 10 different HBB mutations and 30 patients exhibiting 12 different compound heterozygous or homozygous HBB mutations were subjected to DHPLC. The elution profile for the heteroduplex analysis of DHPLC could be successfully used to identify the common disease-causing mutations of HBB. To further confirm the sequence variants, we developed a technique combining multiplex primer-extension analysis coupled with DHPLC for the genotyping of eight common disease-causing mutations in the HBB gene. Overall, by coupling heteroduplex and primer-extension analysis based upon DHPLC, we were able to unambiguously identify the most-common beta-thalassemia mutations corresponding to more than 99% of HBB alleles among the Taiwanese population. In conclusion, compared to classic approaches to mutation screening for this malady, we suggest that DHPLC is an excellent technique to be applied to the genetic screening of prenatal and postnatal individuals as a part of a diagnosis program for beta-thalassemia and provides a more-efficient, economic, and sensitive means to undertake such a screening program. 相似文献
59.
Lupus-related advanced liver involvement as the initial presentation of systemic lupus erythematosus. 总被引:1,自引:0,他引:1
Ming-Chi Lu Ko-Jen Li Song-Chou Hsieh Cheng-Han Wu Chia-Li Yu 《Journal of microbiology, immunology, and infection》2006,39(6):471-475
BACKGROUND AND PURPOSE: Systemic lupus erythematosus (SLE), a prototype of systemic autoimmune disease characterized by multiorgan involvement with diverse clinical and serological manifestations, principally affects women in their child-bearing years. Clinically significant hepatic abnormality as the initial presentation of SLE has rarely been reported. METHODS: Eleven patients with lupus with initial presentation of lupus-related hepatitis were included in this retrospective review. Clinical manifestation, immunological profiles, and risk factors for poor prognosis were analyzed. RESULTS: The most commonly associated clinical manifestations were found to be thrombocytopenia, leukopenia, advancing age, and presence of anti-SSA/Ro antibody and anti-thyroid antibodies. The diagnosis of SLE was delayed due to dominant hepatic abnormalities. Age greater than 50 years and marked hepatic decompensation in accordance with Child classification B and C might suggest poor prognosis (p=0.06). However, the p value was not statistically significant because of the small sample size. CONCLUSIONS: Lupus-related hepatitis, particularly in late-onset lupus, is common. In addition, the presence of anti-SSA, anti-thyroglobulin, and anti-microsomal antibodies is indicative of hepatic involvement in patients with SLE. 相似文献
60.
Kue-Hsiung Hsieh 《Journal of clinical immunology》1989,9(2):111-118
The working mechanism(s) of immunotherapy still remains ill defined. As T cells bearing CD8 antigen possess suppressor/cytotoxic function, this study was conducted to examine the effect of immunotherapy on the production of CD8 antigen. Peripheral blood mononuclear cells (MNC) were obtained from 21 newly diagnosed and 23 hyposensitized (>1 year) asthmatic children and 13 agematched normal children. MNC were stimulated with crude mite extract (Dermatophagoides farinae) for 7 days and with phytohemagglutinin and concanavalin A for 3 days. The CD8 antigen and interleukin-2 receptor (IL-2R) in plasmas and culture supernatants were measured by CELLFREE T8 and IL-2R test kits (T Cell Sciences, USA). The results showed the following. (1) Plasma CD8 antigen was markedly increased in new patients compared to normals (536.7 ± 212.3 vs 222.5 ± 104.0 units/ml;P<0.001) and decreased to normal after immunotherapy (275.7 ± 98.5 units/ml). (2) When stimulated with mite allergen, MNC from both new and hyposensitized patients produced a much greater amount of CD8 antigen compared to those from normals. However, after immunotherapy MNC tended to produce less CD8 antigen, although not to a significant degree. (3) No difference in CD8 antigen production was seen among three groups when lymphocytes were stimulated with mitogens. (4) Production of CD8 antigen paralleled that of IL-2R. Thus, CD8 production was specifically decreased after immunotherapy and this fact reflects a hyposensitized state of T cells after long-term, repeated injection of allergens. 相似文献