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51.
Glioblastoma muhiforme (GBM) is a highly invasive brain tumour that is unvaryingly fatal in humans clesplte even aggres- sive therapeutic approaches such as surgical resection followed by chemotherapy and radiotherapy. Unconventional treatment options such as gene therapy provide an intriguing option for curbing glioma related deaths. To date, gene therapy has yielded encouraging results in preclinical animal models as well as promising safety profiles in phase I clinical trials, but has failed to demonstrate significant therapeutic efficacy in phase III clinical trials. The most widely studied antiglioma gene therapy strategies are suicide gene therapy, genetic immuno- therapy and oncolytic virotherapy, and we have attributed the challenging transition of these modalities into the clinic to four major road- blocks : ( 1 ) anatomical features of the central nervous system, (2) the host immune system, (3) heterogeneity and invasiveness of GBM and (4) limitations in current GBM animal models. In this review, we discuss possible ways to jump these hurdles and develop new gene therapies that may be used alone or in synergy with other modalities to provide a powerful treatment option for patients with GBM. 相似文献
52.
Quinn KJ McCarty EJ Quah SP Emerson CR Donnelly CM 《International journal of STD & AIDS》2012,23(2):136-137
The British HIV Association (BHIVA) has published guidelines for immunization of HIV-infected adults. A chart review of 200 HIV-infected patients diagnosed was conducted to determine shortcomings in previous practice and determine which vaccines should routinely be given in specialist HIV clinics and which might be able to be delegated to primary care clinics. Data were collected on administration of three categories of vaccinations: (1) vaccines used in all individuals with chronic disease (pneumococcal, influenza, swine flu H1N1); (2) targeted vaccinations used in non-immune individuals with HIV who are at risk of exposure (hepatitis A and hepatitis B); (3) routine vaccines traditionally delivered to the whole population (measles/mumps/rubella [MMR], diphtheria/tetanus/pertussis and meningitis C/ACWY). Pneumococcal vaccine was delivered to 54% of eligible patients, 52% of eligible individuals completed a full hepatitis B programme of vaccination and 21% (42/200) were naturally immune; hepatitis A vaccine was delivered to 36% of eligible individuals. With increasing demands on resources, it seems likely that HIV services will have to harness resources of primary care in vaccine programmes in relation to routine vaccines. By improving communication between primary and secondary care mistakes with live vaccination decisions could be avoided; HIV services should continue to perform targeted and chronic disease vaccines, i.e. for category 1 and category 2 vaccines. 相似文献
53.
Koh YW Shah MH Agarwal K McCarty SK Koo BS Brendel VJ Wang C Porter K Jarjoura D Saji M Ringel MD 《Endocrine-related cancer》2012,19(1):29-38
Clinical trials using kinase inhibitors have demonstrated transient partial responses and disease control in patients with progressive medullary thyroid cancer (MTC). The goal of this study was to identify potential combinatorial strategies to improve on these results using sorafenib, a multikinase inhibitor with activity in MTC, as a base compound to explore signaling that might predict synergystic interactions. Two human MTC cell lines, TT and MZ-CRC-1, which harbor endogenous C634W or M918T RET mutations, respectively, were exposed to sorafenib, everolimus, and AZD6244 alone and in combination. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide (MTT) and poly (ADP-ribose) polymerase (PARP) cleavage assays were performed to measure cell survival and apoptosis. Western blots were performed to confirm activity of the compounds and to determine possible mechanisms of resistance and predictors of synergy. As a solitary agent, sorafenib was the most active compound on MTT assay. Western blots confirmed that sorafenib, everolimus, and AZD6244 inhibited their anticipated targets. At concentrations below its IC(50), sorafenib-treated TT and MZ-CRC-1 cells demonstrated transient inhibition and then re-activation of Erk over 6?h. In concordance, synergistic effects were only identified using sorafenib in combination with the Mek inhibitor AZD6244 (P<0.001 for each cell line). Cells treated with everolimus demonstrated activation of Akt and Ret via TORC2 complex-dependent and TORC2 complex-independent mechanisms respectively. Everolimus was neither additive nor syngergistic in combination with sorafenib or AZD6244. In conclusion, sorafenib combined with a Mek inhibitor demonstrated synergy in MTC cells in vitro. Mechanisms of resistance to everolimus in MTC cells likely involved TORC2-dependent and TORC2-independent pathways. 相似文献
54.
Robert DOrtenzio Stefano Tolhurst Melissa Harvey Ravi Ghag Manraj KS Heran 《Journal of Radiology Case Reports》2021,15(3):1
Mass lesions presenting at the craniocervical junction often present a unique challenge due to the complex anatomic arrangement limiting access for tissue diagnosis. The transoral approach has predominantly been used for percutaneous vertebroplasty of high cervical vertebrae with limited literature describing image guided biopsy for bony lesions in this region in the pediatric patient. We describe a technique of computed tomography guided transoral biopsy of a poorly differentiated chordoma located at the C1–C2 level in a 5-year-old child, and review this diagnosis. 相似文献
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58.
Krogmeier MJ McCarty GW Bremner JM 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(21):8189-8191
Recent work in our laboratory showed that the adverse effect of urea fertilizer on seed germination and seedling growth in soil is due to ammonia produced through hydrolysis of urea by soil urease (NH2CONH2 + H2O → 2NH3 + CO2) and can be eliminated by amending the fertilizer with a small amount of a urease inhibitor such as phenylphosphorodiamidate. Because the leaf-tip necrosis often observed after foliar fertilization of plants with urea is usually attributed to ammonia formed through hydrolysis of urea by plant urease, we studied the possibility that this necrosis could be eliminated or reduced by adding phenylphosphorodiamidate to the urea fertilizer. We found that, although addition of this urease inhibitor to foliar-applied urea increased the urea content and decreased the ammonia content and urease activity of soybean [Glycine max. (L.) Merr.] leaves fertilized with urea, it increased the leaf-tip necrosis observed after fertilization. We conclude that this necrosis resulted from accumulation of toxic amounts of urea rather than from formation of toxic amounts of ammonia. This conclusion was supported by our finding that the necrotic areas of soybean leaves treated with urea or with urea and phenylphosphorodiamidate contained much higher concentrations of urea than did the nonnecrotic areas. 相似文献
59.
Ishiguro A; Spirin KS; Shiohara M; Tobler A; Gombart AF; Israel MA; Norton JD; Koeffler HP 《Blood》1996,87(12):5225-5231