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1.
Ghali RP  Herx LM  Maa A  Levine RL 《Brain research》2000,854(1-2):178-188
Patterns of proliferation and changes in non-neuronal cell number in the visual system of the goldfish have been quantitatively examined during optic axon regeneration after an optic nerve crush (ONC). In addition, in order to examine the effect of the regenerating axons on cellular responses in the visual pathways, we did a similar analysis of animals with the right eye removed (ER). Finally, we used double labeling protocols to demonstrate that the proliferating cells that we were counting were mostly phagocytic cells of the mononuclear lineage. In animals with an ONC, we observed an early burst of proliferation that peaked between 7 and 14 days after surgery in all parts of the visual system. In the optic tract, there was also a secondary rise that peaked at 21 days. Levels of proliferation returned to normal by 32 days postoperative in the tract and tectum, while they remained somewhat elevated in the optic nerve for at least 93 days. The total number of non-neuronal cells in the visual paths also rose to peak values between 7 and 14 days after ONC surgery. In the optic tract and tectum, the values fell rapidly after this time, while in the optic nerve, there was a secondary peak at 32 days after which values remained elevated for the duration of the experiment. As compared to animals with an ONC, enucleation resulted in elevated proliferation and hyperplasia at early postoperative intervals. However, because these differences occurred when axons had not yet regenerated into the affected structures, these data do not provide strong evidence for a direct effect of regenerating optic axons on the early cellular responses during Wallerian degeneration in the goldfish. In addition, in the tectum, there was an early increment in cell number that was not associated with elevated levels of proliferation. We believe that this increment represents immigration of resident microglia from other regions of the brain.  相似文献   
2.
Papillary thyroid carcinoma (PTC) is the most common type of thyroid carcinoma. CIP2A has recently been described as a prognostic marker in many cancers. In this study, we assessed the value of this novel prognostic marker in PTC. A total of 178 surgical specimens of both benign and malignant thyroid tumors were collected. Immunohistochemical staining for CIP2A, HBME‐1, galectin‐3, and CK19 was performed. Western blotting for CIP2A was also performed. CIP2A was expressed in 85.3% of malignant tumors and 12.1% of benign tumors. ROC analysis showed that the AUC for CIP2A was higher than those for other tumor markers. Western blotting showed that CIP2A expression was higher in PTC than in other tumors. Poor progression‐free survival was observed in the high‐CIP2A expression group. High CIP2A expression is a poor prognostic factor and can be a diagnostic marker in PTC. The presence of any two of the three indicated makers (CIP2A, galectin‐3, and HBME‐1) is strongly correlated with the diagnosis of PTC.  相似文献   
3.
The suprahepatic space represents a potential reservoir for cerebrospinal fluid absorption and becomes critical when extensive abdominal adhesions prevent passage of a peritoneal shunt catheter toward the pelvis. We present a patient with refractory hydrocephalus in which a multishunt system with drainage into the suprahepatic space was ultimately successful in decompressing the patient’s trapped ventricular spaces.  相似文献   
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5.
Reports on pediatric low-grade diffuse glioma WHO-grade II (DG2) suggest an impaired survival rate, but lack conclusive results for genetically defined DG2-entities. We analyzed the natural history, treatment and prognosis of DG2 and investigated which genetically defined sub-entities proved unfavorable for survival. Within the prospectively registered, population-based German/Swiss SIOP-LGG 2004 cohort 100 patients (age 0.8-17.8 years, 4% neurofibromatosis [NF1]) were diagnosed with a DG2. Following biopsy (41%) or variable extent of resection (59%), 65 patients received no adjuvant treatment. Radiologic progression or severe neurologic symptoms prompted chemotherapy (n = 18) or radiotherapy (n = 17). Multiple lines of salvage treatment were necessary for 19/35 patients. Five years event-free survival dropped to 0.44, while 5 years overall survival was 0.90 (median observation time 8.3 years). Extensive genetic profiling of 65/100 DG2 identified Histone3-K27M-mutation in 4, IDH1-mutation in 11, BRAF-V600-mutation in 12, KIAA1549-BRAF-fusions in 6 patients, while the remaining 32 tumor tissues did not show alterations of these genes. Progression to malignant glioma occurred in 12 cases of all genetically defined subgroups within a range of 0.5 to 10.8 years, except for tumors carrying KIAA1549-BRAF-fusions. Histone3-K27M-mutant tumors proved uniformly fatal within 0.6 to 2.4 years. The current LGG treatment strategy seems appropriate for all DG2-entities, with the exemption of Histone3-K27M-mutant tumors that require a HGG-related treatment strategy. Our data confirm the importance to genetically define pediatric low-grade diffuse gliomas for proper treatment decisions and risk assessment.  相似文献   
6.
It is well known that protein/peptide-based drug formulations are more stable in the solid state than in the liquid state, thereby offering stability advantages in ambient temperature storage, product shipping/distribution, and long-term shelf life. Novel powder-based drug delivery systems recently emerging for applications in sustained release, inhalation, intradermal delivery, etc, add more value to protein solid dosage forms. Despite great research interests in understanding the drying effects on protein stability and a large collection of publications focusing on this area, systematic accounts of powder formation techniques are lacking. This review is to summarize a number of methods currently available for protein powder preparation. Some are common methods such as lyophilization, spray drying, pulverization, and precipitation, and some methods are more recently developed such as supercritical fluid precipitation, spray-freeze drying, fluidized-bed spray coating and emulsion precipitation. In addition to examining the individual process effect on protein stability that is always the focus of formulation scientists, this review also likes to evaluate each method from a more practical sense in terms of process versatility and scalability. The conclusion is that each method has its own advantages and the use of a method is formulation and application specific. With the understanding of the principles and advantages of these methods, it can benefit our choice on selecting appropriate techniques for preparing a desired protein powder formulation for specific applications.  相似文献   
7.
Due to the presence of a network of antigen-presenting cells and other cells with innate and adaptive immune functions, the skin is both a sensitive immune organ and a practical target site for vaccine administration. A handful of needle-free immunization technologies have emerged in recent years that aim to take advantage of these characteristics. Skin delivery technologies provide potentially safer alternatives to needle injection and promises increased efficacy in the prevention and/or therapy of infectious diseases, allergic disorders and cancer. In this review, we will cover advances in needle-free skin vaccination technologies and their potential applications to disease prevention and therapy. Emphasis will be placed on epidermal powder immunization and particle-mediated ('gene gun') DNA immunization, which use similar mechanical devices to deliver protein and DNA vaccines, respectively, into the viable epidermis.  相似文献   
8.
Maa MC  Hsieh CY  Leu TH 《Oncogene》2001,20(1):106-112
Two isoforms of Eps8, p97Eps8 and p68Eps8, have been identified as the substrates for receptor tyrosine kinases. Our previous studies indicated that both tyrosyl phosphorylation and protein expression of Eps8 were elevated in v-Src transformed cells. In an attempt to examine the role played by p97Eps8 in tumorigenesis, we have first obtained cells overexpressing p97Eps8 and its pleckstrin homology (PH)-truncated variant. We then demonstrated that cells overexpressing p97Eps8 not only exhibited the ability of focus formation in cell culture but also promoted the tumor formation in mice as compared to controls. Furthermore, elevated serum-induced extracellular responsive kinase (ERK) activation was observed in p97Eps8 overexpressors. This enhanced ERK activation was sensitive to a MEK1 specific inhibitor PD98059 and was important for p97Eps8-mediated transformation, since transfection of vectors expressing dominant negative MEK1 and p97Eps8 abrogated focus formation by p97Eps8. In contrast, PH-truncated p97Eps8 failed to localize at the plasma membrane and that the truncated variant also did not elevate ERK activation and cellular transformation in response to serum stimulation. Our results thus indicated that: (i) the gene encoding p97Eps8 was an oncogene; (ii) p97Eps8-induced oncogenesis was partly mediated by ERK activation; and (iii) the PH domain of p97Eps8 was critical for its cellular localization, ERK activation and its ability to transform cells. Oncogene (2001) 20, 106 - 112.  相似文献   
9.
Purpose. To study the effect of trehalose, lactose, and mannitol on the biochemical stability and aerosol performance of spray-dried powders of an anti-IgE humanized monoclonal antibody. Methods. Protein aggregation of spray-dried powders stored at various temperature and relative humidity conditions was assayed by size exclusion chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis. Protein glycation was determined by isoelectric focusing and affinity chromatography. Crystallization was examined by X-ray powder diffraction. Aerosol performance was assessed as the fine particle fraction (FPF) of the powders blended with coarse carrier lactose, and was determined using a multiple stage liquid impinger. Results. Soluble protein aggregation consisting of non-covalent and disulfide-linked covalent dimers and trimers occurred during storage. Aggregate was minimized by formulation with trehalose at or above a molar ratio in the range of 300:1 to 500:1 (excipient:protein). However, the powders were excessively cohesive and unsuitable for aerosol administration. Lactose had a similar stabilizing effect, and the powders exhibited acceptable aerosol performance, but protein glycation was observed during storage. The addition of mannitol also reduced aggregation, while maintaining the FPF, but only up to a molar ratio of 200:1. Further increased mannitol resulted in crystallization, which had a detrimental effect on protein stability and aerosol performance. Conclusions. Protein stability was improved by formulation with carbohydrate. However, a balance must be achieved between the addition of enough stabilizer to improve protein biochemical stability without compromising blended powder aerosol performance.  相似文献   
10.
Pancreatic oedema occurs early in the development of acute pancreatitis, and the overall extent of fluid loss correlates with disease severity. The tachykinin substance P (SP) is released from sensory nerves, binds to the neurokinin-1 receptor (NK1-R) on endothelial cells and induces plasma extravasation, oedema, and neutrophil infiltration, a process termed neurogenic inflammation. We sought to determine the importance of neurogenic mechanisms in acute pancreatitis. Pancreatic plasma extravasation was measured using the intravascular tracers Evans blue and Monastral blue after administration of specific NK1-R agonists/antagonists in rats and NK1-R(+/+)/(-/-) mice. The effects of NK1-R genetic deletion/antagonism on pancreatic plasma extravasation, amylase, myeloperoxidase (MPO), and histology in cerulein-induced pancreatitis were characterized. In rats, both SP and the NK1-R selective agonist [Sar(9) Met(O(2))(11)]SP stimulated pancreatic plasma extravasation, and this response was blocked by the NK1-R antagonist CP 96,345. Selective agonists of the NK-2 or NK-3 receptors had no effect. In rats, cerulein stimulated pancreatic plasma extravasation and serum amylase. These responses were blocked by the NK1-R antagonist CP 96,345. In wildtype mice, SP induced plasma extravasation while SP had no effect in NK1-R knockout mice. In NK1-R knockout mice, the effects of cerulein on pancreatic plasma extravasation and hyperamylasemia were reduced by 60%, and pancreatic MPO by 75%, as compared to wildtype animals. Neurogenic mechanisms of inflammation are important in the development of inflammatory oedema in acute interstitial pancreatitis.  相似文献   
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