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41.
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43.
Anticocaine catalytic antibodies 总被引:5,自引:0,他引:5
Cocaine mediates its reinforcing and toxic actions through a "loss of function" effect at multiple receptors. The difficulties inherent in blocking a pleiotropic blocker pose a great obstacle for the classical receptor-antagonist approach and have contributed to the failure (to date) to devise specific treatments for cocaine overdose and addiction. As an alternative, we have embarked on an investigation of catalytic antibodies, a programmable class of artificial enzyme, as "peripheral blockers" -- agents designed to bind and degrade cocaine in the circulation before it partitions into the central nervous system to exert reinforcing or toxic effects. We synthesized transition-state analogs of cocaine's hydrolysis at its benzoyl ester, immunized mice, prepared hybridomas and developed the first anticocaine catalytic antibodies with the capacity to degrade cocaine to nonreinforcing, nontoxic products. We subsequently identified several families of anticocaine catalytic antibodies and found that the most potent antibody possessed sufficient activity to block cocaine-induced reinforcement, organ dysfunction and sudden death in rodent models of addiction, toxicity and overdose, respectively. With the potential to promote cessation of use, prolong abstinence and provide a treatment for acute overdose, the artificial enzyme approach comprehensively responds to the problem of cocaine. 相似文献
44.
作者对抗体包被的红为性进行研究,发现抗体包被改变了红细胞的变形性,在我们研究的抗体量范围内,抗体量越多,红细胞的变形性越小,作者从血液流变学的角度对上述结果作了讨论,并提出了通过测定其对红细胞变形性的影响来比较准确地标定抗体效价的可能性。 相似文献
45.
Immunohistochemical study of nasopharyngeal carcinoma using monoclonal keratin antibodies 总被引:2,自引:1,他引:2 下载免费PDF全文
S R Shi M L Goodman A K Bhan B Z Pilch L B Chen T T Sun 《The American journal of pathology》1984,117(1):53-63
Nasopharyngeal carcinoma (NPC) provides a unique opportunity to evaluate distinctive epidemiologic features and a possible etiologic relationship with Epstein-Barr virus (EBV) in human malignancy. The lack of a uniformly accepted pathologic classification for NPC has limited the application of this data, although the World Health Organization (WHO) developed a classification that may solve this problem. Monoclonal keratin antibodies were used for staining of NPC for evaluation of its assistance in diagnosis and classification. In the present immunohistochemical study, monoclonal keratin antibodies, designated AE1, AE2, and AE3, and a polyclonal keratin antibody (RAK) were used for study of the presence of keratin in 121 cases of NPC obtained from China and the United States. AE1 monoclonal antibody, which recognizes keratin protein classes 56.5K, 50K, and 40K, was shown to be the most sensitive and specific for NPC tumor cells among the keratin antibodies studied. In addition, some different keratin expression patterns could be identified between different kinds of epithelium and different tumor groups, with possible relevance to the histogenesis of the histologic subtypes of NPC. 相似文献
46.
Mengshu Zhang Likui Lu Bin Wei Yingying Zhang Xiang Li Yajun Shi Wei Ge Miao Sun 《American journal of medical genetics. Part A》2020,182(10):2432-2436
Brachydactyly type A (BDA) is defined as short middle phalanges of the affected digits and is subdivided into four types (BDA1‐4). To date, the molecular cause is unknown. However, there is some evidence that pathogenic variants of HOXD13 could be associated with BDA3 and BDA4. Here, we report a Chinese autosomal dominant BDA3 pedigree with a novel HOXD13 mutation. The affected individuals presented with an obviously shorter fifth middle phalanx. The radial side of the middle phalanx was shorter than the ulnar side, and the terminal phalanx of the fifth finger inclined radially and formed classical clinodactyly. Interestingly, the index finger was normal. The initial diagnosis was BDA3. However, the distal third and fourth middle phalanges were also slightly affected, resulting in mild radial clinodactyly. Both feet showed shortening of the middle phalanges, which were fused to the distal phalanges of the second to the fifth toes, as reported in BDA4. Therefore, this pedigree had combined BDA3 and atypical BDA4. By direct sequencing, a 13 bp deletion within exon 1 of HOXD13 (NM_000523.4: c.708_720del13; NP_000514.2: p.Gly237fs) was identified. The 13 bp deletion resulted in a frameshift and premature termination of HOXD13. This study provides further evidences that variants in HOXD13 cause BDA3‐BDA4 phenotypes. 相似文献
47.
Isolation of a new clathrin heavy chain gene with muscle-specific expression from the region commonly deleted in velo-cardio-facial syndrome 总被引:3,自引:4,他引:3
Sirotkin H; Morrow B; DasGupta R; Goldberg R; Patanjali SR; Shi G; Cannizzaro L; Shprintzen R; Weissman SM; Kucherlapati R 《Human molecular genetics》1996,5(5):617-624
Velo-cardio-facial syndrome (VCFS) and DiGeorge syndrome (DGS) are
developmental disorders characterized by a spectrum of phenotypes including
velopharyngeal insufficiency, conotruncal heart defects and facial
dysmorphology among others. Eighty to eighty-five percent of VCFS/DGS
patients are hemizygous for a portion of chromosome 22. It is likely that
the genes encoded by this region play a role in the etiology of the
phenotypes associated with the disorders. Using a cDNA selection protocol,
we isolated a novel clathrin heavy chain cDNA (CLTD) from the VCFS/DGS
minimally deleted interval. The cDNA encodes a protein of 1638 amino acids.
CLTD shares significant homology, but is not identical to the ubiquitously
expressed clathrin heavy chain gene. The CLTD gene also shows a unique
pattern of expression, having its maximal level of expression in skeletal
muscle. Velopharyngeal insufficiency and muscle weakness are common
features of VCFS patients. Based on the location and expression pattern of
CLTD, we suggest hemizygosity at this locus may play a role in the etiology
of one of the VCFS-associated phenotypes.
相似文献
48.
气管组织工程的研究策略及其展望 总被引:1,自引:0,他引:1
气管组织工程是近10年来国内外研究的热点和难点问题,取得了一些进展.但如何更好地遴选基质材料、实现种子细胞共培养、上皮化以及再血管化来构建组织工程化气管仍需要不断寻求新的研究思路和策略.本文从气管重建和理想化气管替代物的角度,回顾了近年来在组织工程气管方面的研究进展,并对未来的研究作出展望. 相似文献
49.
Yasuyuki Sumikawa Yuriko Ueki Akira Miyoshi Lei Cheng Min Yin Hai-Bo Shi Masuko Daitoku Sumikawa Takeshi Kono Toshiyuki Aoki Ichiro Katayama 《Arerugī》2007,56(10):1270-1275
BACKGROUND: The comparative studies of the prevalence of atopic dermatitis and skin barrier functions in Japanese and Chinese were performed. METHODS: Clinical investigations were performed in 68 elementary school students in Lhasa, Tibet Autonomous Region and 67 students in Yixing, Jiangsu Province in China, and 99 students in Nishinomiya, Hyogo in Japan. Transepidermal water loss (TEWL) and capacitance were measured. Questionary survey about bathing frequency was also performed for students in Lhasa, Yixing and Osaka. RESULT: The prevalence rate of atopic dermatitis was 0% in Lhasa, 2.63% in Yixing, 4.26% in Nishinomiya. TEWL of students in Nishinomiya was higher than that in Yixing and Lhasa. Capacitance of students in Lhasa was lower than that in Nishinomiya and Yixing. The frequency of taking a bath in Lhasa was about 2.2 times per month and fewer than that in Nishinomiya and Yixing. CONCLUSION: There was tendency that the prevalence of atopic dermatitis increased according to increase of TEWL. It was thought that more investigations are necessary whether the development of habitat and environment influence the prevalence of atopic dermatitis and skin barrier function. 相似文献
50.
Ping Ii Hiroshi Kawachi Tetsuo Morioka Mlchiaki Orikasa Takashi Oite Zhen Sheng Shi Fujio Shimizu 《Pathology international》1997,47(7):430-435
The effects of treditional Chinese medlclne (Salrel-to) on experimental glomerulonephritls Induced In rats by monodonal antibody (mAb) 1–22–3 lnjectlon was examined. The level of proteinuria in the Sairel-to-treated group was significantly lower than that In the PBS treated group. This suppressive effect was caused by the major component of Sealer-to, Syo-salko-to but not by another component, Gorel-san. The suppressive effect of Syo-salko-to was Identified In Its components ( Bupleuri radix, Pindilae tuber and Zingibers rhizoma ), but not In the other combined components ( Ginseng radix and Zizyphl fructus ). Further study weeled that the suppressive effects of the combined components were mainly derived from Bupleuri radix . It was demonstrated that the actual active Ingredient is probably Salkosaponin-d. Light microscopy revealed that Sairel-to and Its effective components suppressed the proliferation of mesanglal cells and mesanglal matrix expansion. Semi quantitative morphological studies of glomerular lesions on the eighth day showed that Syo-salko-to and Its combined components ( Bupleuri radix, Zinglberis rhizoma and Pinelliae tuber ) suppressed mesanglal matrix expansion significantly compared with phosphate-buffered saline control groups (matrix score: 28.0±19.1 vs 102.3±14.1; 30.9±30.1 vs 102.3±14.1, p<0.005, respectively). It was concluded that Salkosaponln-d, as well as Bupleuri radix , Syo-salko-to and Sairel-to can suppress proteinurla and morphological changes In the rat glomerulonephritls model Induced by mAb 1–22–3. 相似文献