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961.
962.
《Best Practice & Research: Clinical Haematology》2021,34(3):101277
As we expand our acumen of the intricacies of hematological malignancies at a genetic and cellular level, we have paved the way in advancing novel targeted therapeutic avenues such as chimeric antigen receptor T-cell therapies (CAR T). Engineering cells to target a specific antigen has led to dramatic remission rates in cases of relapsed/refractory non-Hodgkin lymphoma, acute lymphoblastic leukemia as well as multiple myeloma thus far with trials in place to further advance targeted therapies in other hematological malignancies. Most currently available CAR T therapies target CD19 antigen. Studies are underway exploring novel CAR T products aimed at other tumor-specific antigens with potential to improve the efficacy and reduce the toxicities. Early studies have confirmed safety and efficacy of CD22 and BCMA targeted CAR T therapies. Moreover, various other targets including CD20, CD30, CD123, kappa, and lambda light chains among others are under clinical investigation as potential avenues of targeted therapy. This review highlights the shift in the treatment paradigm in pursuing diverse antigen targets while addressing the challenges in terms of the efficacy and toxicity of current CAR T-cell therapies. 相似文献
963.
Improving the Specificity of the Prostate‐Specific Antigen Substrate Glutaryl‐Hyp‐Ala‐Ser‐Chg‐Gln as a Promoiety
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To develop PSA peptide substrates with improved specificity and plasma stability from the known substrate sequence glutaryl‐Hyp‐Ala‐Ser‐Chg‐Gln, systematic replacements of the N‐terminal segment with D‐retro‐inverso‐peptides were performed with the incorporation of 7‐amino‐4‐methylcoumarin (7‐AMC) after Gln for convenient fluorometric determination and ranking of the PSA substrate activity. The D‐retro‐inverso‐peptide conjugates with P2‐P5 D‐amino acid substitutions were moderate but poorer PSA substrates as compared to the original peptide, suggesting that inversion of the amide bonds and/or incorporation of the additional atom as in the urea linker adversely affected PSA binding. However, P5 substitution of Hyp with Ser showed significant improvements in PSA cleavage rate; the resulting AMC conjugate, glutaryl‐Ser‐Ala‐Ser‐Chg‐Gln‐AMC ( 11 ), exhibited the fastest PSA cleavage rate of 351 pmol/min/100 nmol PSA. In addition, GABA←mGly‐Ala‐Ser‐Chg‐Gln‐AMC (conjugate 6 ) was the second best PSA substrate and released 7‐AMC at a rate of 225 pmol/min/100 nmol PSA as compared to 171 pmol/min/100 nmol PSA for the control conjugate glutaryl‐Hyp‐Ala‐Ser‐Chg‐Gln‐AMC. Incubations of selected AMC conjugates with mouse and human plasma revealed that GABA←D‐Ser‐ψ[NH‐CO‐NH]‐Ala‐Ser‐Chg‐Gln‐AMC ( 5 ) and GABA←mGly‐Ala‐Ser‐Chg‐Gln‐AMC ( 6 ) were most stable to non‐PSA‐mediated proteolysis. Our results suggest that the PSA specificity of glutaryl‐Hyp‐Ala‐Ser‐Chg‐Gln is improved with Ser and mGly substitutions of Hyp at the P5. 相似文献
964.
Design,Synthesis, and Biological Evaluation of 1‐(thiophen‐2‐yl)‐9H‐pyrido[3,4‐b]indole Derivatives as Anti‐HIV‐1 Agents
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Penta Ashok Cui‐Lin Lu Subhash Chander Yong‐Tang Zheng Sankarnarayanan Murugesan 《Chemical biology & drug design》2015,85(6):722-728
A novel series of 1‐(thiophen‐2‐yl)‐9H‐pyrido [3,4‐b]indole derivatives were synthesized using DL‐tryptophan as starting material. All the compounds were characterized by spectral analysis such as 1H NMR, Mass, IR, elemental analysis and evaluated for inhibitory potency against HIV‐1 replication. Among the reported analogues, compound 7g exhibited significant anti‐HIV activity with EC50 0.53 μm and selectivity index 483; compounds 7e , 7i , and 7o displayed moderate activity with EC50 3.8, 3.8, and 2.8 μm and selectivity index >105, >105, and 3.85, respectively. Interestingly, compound 7g inhibited p24 antigen expression in acute HIV‐1IIIB infected cell line C8166 with EC50 1.1 μm . In this study, we also reported the Lipinski rule of 5 parameters, predicted toxicity profile, drug‐likeness, and drug score of the synthesized analogues. 相似文献
965.
Minchao Li Jinfeng Zeng Ruiting Li Ziyu Wen Yanhui Cai Jeffrey Wallin Yuelong Shu Xiangjun Du Caijun Sun 《Viruses》2021,13(2)
With the rapid global spread of the Coronavirus Disease 2019 (COVID-19) pandemic, a safe and effective vaccine against human coronaviruses (HCoVs) is believed to be a top priority in the field of public health. Due to the frequent outbreaks of different HCoVs, the development of a pan-HCoVs vaccine is of great value to biomedical science. The antigen design is a key prerequisite for vaccine efficacy, and we therefore developed a novel antigen with broad coverage based on the genetic algorithm of mosaic strategy. The designed antigen has a potentially broad coverage of conserved cytotoxic T lymphocyte (CTL) epitopes to the greatest extent, including the existing epitopes from all reported HCoV sequences (HCoV-NL63, HCoV-229E, HCoV-OC43, HCoV-HKU1, SARS-CoV, MERS-CoV, and SARS-CoV-2). This novel antigen is expected to induce strong CTL responses with broad coverage by targeting conserved epitopes against multiple coronaviruses. 相似文献
966.
967.
The high incidence rates of prostate cancer (PCa) raise demand for improved therapeutic strategies. Prostate tumors specifically express the prostate-specific membrane antigen (PSMA), a membrane-bound protease. As PSMA is highly overexpressed on malignant prostate tumor cells and as its expression rate correlates with the aggressiveness of the disease, this tumor-associated biomarker provides the possibility to develop new strategies for diagnostics and therapy of PCa. Major advances have been made in PSMA targeting, ranging from immunotherapeutic approaches to therapeutic small molecules. This review elaborates the diversity of PSMA targeting agents while focusing on the radioactively labeled tracers for diagnosis and endoradiotherapy. A variety of radionuclides have been shown to either enable precise diagnosis or efficiently treat the tumor with minimal effects to nontargeted organs. Most small molecules with affinity for PSMA are based on either a phosphonate or a urea-based binding motif. Based on these pharmacophores, major effort has been made to identify modifications to achieve ideal pharmacokinetics while retaining the specific targeting of the PSMA binding pocket. Several tracers have now shown excellent clinical usability in particular for molecular imaging and therapy as proven by the efficiency of theranostic approaches in current studies. The archetypal expression profile of PSMA may be exploited for the treatment with alpha emitters to break radioresistance and thus to bring the power of systemic therapy to higher levels. 相似文献
968.
Beta-catenin expression in hepatocellular carcinoma: a possible participation of beta-catenin in the dedifferentiation process 总被引:3,自引:0,他引:3
Suzuki T Yano H Nakashima Y Nakashima O Kojiro M 《Journal of gastroenterology and hepatology》2002,17(9):994-1000
BACKGROUND: beta-Catenin is known as a multifunctional protein acting as a regulator of the cadherin-mediated cell-cell adhesion system and in the Wingless/Wnt signal transduction pathway. Recent studies reported mutation of the beta-catenin gene in some tissues of hepatocellular carcinoma (HCC). METHODS: 'Nodule-in-nodule' appearance is a feature of well-differentiated HCC containing a distinct nodule of less-differentiated cancer tissue inside, and it is presumed to be a morphological expression of the dedifferentiation process. The present study immunohistochemically investigated the beta-catenin expression according to the dedifferentiation process of HCC, that is, in small well-differentiated HCC with indistinct margins, HCC with a 'nodule-in-nodule' appearance, moderately differentiated HCC, which does not have a 'nodule-in-nodule' appearance, and sarcomatous HCC. RESULTS: The expression of beta-catenin was observed in approximately 70% of small well-differentiated HCC with indistinct margins. In HCC with a 'nodule-in-nodule' appearance, membranous expression of beta-catenin was higher in the well-differentiated cancer tissues than in the less-differentiated cancer tissues (P < 0.01), cytoplasmic expression was higher in the less-differentiated cancer tissues (P < 0.01), and nuclear expression was higher in the less-differentiated cancer tissues (P < 0.001). In moderately differentiated HCC, tumors with membranous expression of beta-catenin had more frequent intrahepatic metastasis than those without having the expression (P < 0.001). CONCLUSIONS: Accumulation of beta-catenin was already present in the early stage of HCC, and in less-differentiated cancer tissue the membranous expression of beta-catenin could be related to intrahepatic metastasis. 相似文献
969.
Akio Kawamura Makoto Osanai Masamichi Katori Motoki Yonekawa Masao Saitoh 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》1998,2(4):292-296
Abstract: Leukocytapheresis (LCAP) is widely used for the treatment of immunological diseases. We studied a new treatment of LCAP using a nonwoven polyester filter. In a basic study, 30–70% of the lymphocytes were adsorbed. Also, 30–68% of the lymphocyte subsets were removed. This method was applied to 2 patients with corti-costeroid-resistant active ulerative colitis. Erosion, edema, bleeding, ulcer formation, and stenosis of the colon were almost completely repaired after 6 LCAP treatments. LCAP using a nonwoven polyester filter will be a very useful treatment for immunological diseases and extracorporeal immunomodulation. 相似文献
970.
检测慢性肝病合并腹水形成患者血浆及腹水中CA12 5水平 ,探讨其临床意义。采用ELISA法检测 141例慢性肝病患者血浆CA12 5值 ,对 40例合并腹水的慢性肝病同时测腹水CA12 5值。结果显示 ( 1)慢性肝病合并腹水形成者血浆CA12 5值显著高于无腹水形成者 (P <0 0 1) ;( 2 )腹水中CA12 5值显著高于血浆中值 (P <0 0 1) ,且二者呈正相关 (r=0 965 ,P <0 0 1) ;( 3 )大量放腹水后 ,血浆中及腹水中CA12 5值显著下降 ,且腹水CA12 5值下降的幅度大于血浆CA12 5值下降的幅度 (P <0 0 1)。提示CA12 5是诊断慢性肝病合并腹水形成的一项敏感指标 相似文献