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71.
Hydroxyproline‐rich glycoproteins (HRGPs) constitute a major group of proteins of the extracellular matrix (ECM). The multicellular green alga Volvox carteri is a suitable model organism in which to study the evolutionary transition to multicellularity, including the basic principles and characteristics of an ECM. In Volvox, the ECM is dominated by a single HRGP family: the pherophorins. Our inventory amounts to 117 pherophorin‐related genes in V. carteri. We focused on a pherophorin with an unexpected characteristic: pherophorin‐S is a soluble, non‐cross‐linked ECM protein. Using transformants expressing a YFP‐tagged pherophorin‐S we observed the synthesis and secretion of pherophorin‐S by somatic cells in vivo, and we then traced the protein during its conspicuous migration to the ECM around prehatching juveniles and its localized concentration there. Our results provide insights into how an ECM zone surrounding the progeny is remotely affected by distantly located parental somatic cells. In view of the properties and migration of pherophorin‐S, we conclude that pherophorin‐S is likely to act as an ECM plasticizer to allow for dynamic ECM remodeling.  相似文献   
72.
73.
目的探讨输尿管软镜协同输尿管硬镜治疗复杂上尿路结石的临床效果。方法选择我院收治的复杂上尿路结石患者96例,按入院顺序分为对照组和观察组,每组48例。对照组采取输尿管硬镜钬激光碎石术治疗,观察组采取输尿管软镜协同输尿管硬镜钬激光碎石术治疗。比较两组患者1次性碎石成功率、结石彻底清除率、炎症反应情况以及生活质量、住院时间、术后并发症发生率、疾病复发率。结果观察组患者的1次性碎石成功率、结石彻底清除率均高于对照组,两组比较差异有统计学意义(均P<0.05)。术后3 d,观察组的肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)、C-反应蛋白(CRP)水平均较对照组降低,差异有统计学意义(均P<0.05)。术后1周,两组患者的生活质量比较,观察组的生活质量量表(SF-36)评分明显高于对照组,住院时间短于对照组,两组比较差异有统计学意义(均P<0.05)。两组患者的并发症发生率、疾病复发率比较,观察组均明显低于对照组,差异有统计学意义(均P<0.05)。结论输尿管软镜联合输尿管硬镜治疗复杂上尿路结石的效果满意,且创伤小,结石清除率高,不良反应低,具有一定临床应用价值。  相似文献   
74.
为明确南洋臀纹粉蚧Planococcus lilacinus(Cockerell)雌成虫及其蜡泌物的结构特征,利用扫描电镜观察该虫体表主要器官、蜡质及泌蜡腺体的超微结构.结果表明:南洋臀纹粉蚧雌成虫外覆白色粉状厚蜡被,体缘具18对蜡棒,触角8节、口器和足发达且分布有不同长度的毛形和刺形感受器,眼为单眼,腹脐和背孔唇形、发达;体表蜡质包含带状蜡丝、空心管状蜡丝和月牙形蜡丝,由三格腺和刺孔群分泌的带状蜡丝大量分布于整个虫体,由管状腺分泌的空心管状蜡丝主要分布于虫体腹部腹面和体缘,由多格腺分泌的月牙形蜡丝主要分布于虫体腹部腹面.研究结果初步揭示了南洋臀纹粉蚧雌成虫体表主要器官、蜡质及泌蜡腺体的超微结构特征,可为研究该虫搜索寄主、寻找配偶、群集为害、抵御逆境和传播扩散等行为活动提供支持.  相似文献   
75.
PurposeTo investigate the efficacy of a newly-developed laser-heated core biopsy needle in the thermal ablation of biopsy tract to reduce hemorrhage after biopsy using in vivo rabbit’s liver model.Materials and methodsFive male New Zealand White rabbits weighed between 1.5 and 4.0 kg were anesthetized and their livers were exposed. 18 liver biopsies were performed under control group (without tract ablation, n = 9) and study group (with tract ablation, n = 9) settings. The needle insertion depth (~3 cm) and rate of retraction (~3 mm/s) were fixed in all the experiments. For tract ablation, three different needle temperatures (100, 120 and 150 °C) were compared. The blood loss at each biopsy site was measured by weighing the gauze pads before and after blood absorption. The rabbits were euthanized immediately and the liver specimens were stained with hematoxylin-eosin (H&E) for further histopathological examination (HPE).ResultsThe average blood loss in the study group was reduced significantly (p < 0.05) compared to the control group. The highest percentage of bleeding reduction was observed at the needle temperature of 150 °C (93.8%), followed by 120 °C (85.8%) and 100 °C (84.2%). The HPE results show that the laser-heated core biopsy needle was able to cause lateral coagulative necrosis up to 14 mm diameter along the ablation tract.ConclusionThe laser-heated core biopsy needle reduced hemorrhage up to 93.8% and induced homogenous coagulative necrosis along the ablation tract in the rabbits’ livers. This could potentially reduce the risk of tumor seeding in clinical settings.  相似文献   
76.
Oncoproteomics is the term used to describe the application of proteomic technologies in oncology and parallels the related field of oncogenomics. It is now contributing to the development of personalized management of cancer. Proteomic technologies are used for the identification of biomarkers in cancer, which will facilitate the integration of diagnosis and therapy of cancer. Molecular diagnostics, laser capture microdissection and protein biochips are among the technologies that are having an important impact on oncoproteomics. The discovery of protein patterns developed by the US Food and Drug Administration/National Cancer Institute Clinical Proteomics Program is capable of distinguishing cancer and disease-free states with high sensitivity and specificity and will also facilitate the development of personalized therapy of cancer. Examples of application are given for breast and prostate cancer and a selection of companies and their collaborations that are developing application of proteomics to personalized treatment of cancer are discussed. Continued refinement of techniques and methods to determine the abundance and status of proteins in vivo holds great promise for the future study of normal cells and the pathology of associated neoplasms. Personalized cancer therapy is expected to be in the clinic by the end of the first decade of the 21st century.  相似文献   
77.
News in Brief     
Archival formalin-fixed, paraffin-embedded (FFPE) tissue and their associated diagnostic records represent an invaluable source of retrospective proteomic information on diseases for which the clinical outcome and response to treatment are known. However, analysis of archival FFPE tissues by high-throughput proteomic methods has been hindered by the adverse effects of formaldehyde fixation and subsequent tissue histology. This review examines recent methodological advances for extracting proteins from FFPE tissue suitable for proteomic analysis. These methods, based largely upon heat-induced antigen retrieval techniques borrowed from immunohistochemistry, allow at least a qualitative analysis of the proteome of FFPE archival tissues. The authors also discuss recent advances in the proteomic analysis of FFPE tissue; including liquid-chromatography tandem mass spectrometry, reverse phase protein microarrays and imaging mass spectrometry.  相似文献   
78.
Evaluation of: Wulfkuhle JD, Berg D, Wolff C et al. Molecular analysis of HER2 signaling in human breast cancer by functional protein pathway activation mapping. Clin. Cancer Res. 18(23), 6426–6435 (2012).

Exhaustive characterization and mapping of pivotal molecules and downstream effectors deregulated in breast cancer is of fundamental clinical value to define the most effective therapy. Wulfkuhle et al. applied reverse-phase protein microarray, a highly sensitive immunoassay able to perform quantitative and multiplexed analysis of total and/or modified cellular proteins, to assess protein levels and activation/phosphorylation status of the HER family (EGFR, HER2, HER3) and downstream signaling molecules in HER2+ and HER2- breast cancers. The research was performed using laser capture microdissected tumor epithelial cells from frozen samples and formalin-fixed paraffin embedded specimens, which were also analyzed by immunohistochemistry (IHC) and FISH. This study identified a subgroup of IHC/FISH/HER2- patients with HER2 activation/phosphorylation levels comparable with those obtained from IHC/FISH/HER2+ tumors. HER2 signaling activation was independent from total HER2 expression and involved HER3 and EGFR activation. These findings indicate that molecular characterization by reverse-phase protein microarray of HER2 and its partners/effectors in the signaling cascade enables the identification of a subgroup of IHC/FISH/HER2- patients showing HER2 signaling activation. These patients, currently excluded from targeted therapy administration, could potentially benefit from this and it could improve prognosis and survival.  相似文献   
79.

Background

Aspergillus fumigatus conidia can exacerbate asthma symptoms. Phagocytosis of conidia is a principal component of the host antifungal defense. We investigated whether allergic airway inflammation (AAI) affects the ability of phagocytic cells in the airways to internalize the resting fungal spores.

Methods

Using BALB/c mice with experimentally induced AAI, we tested the ability of neutrophils, macrophages, and dendritic cells to internalize A. fumigatus conidia at various anatomical locations. We used light microscopy and differential cell and conidium counts to determine the ingestion potential of neutrophils and macrophages present in bronchoalveolar lavage (BAL). To identify phagocyte-conidia interactions in conducting airways, conidia labeled with tetramethylrhodamine-(5-(and-6))-isothiocyanate were administered to the oropharyngeal cavity of mice. Confocal microscopy was used to quantify the ingestion potential of Ly-6G+ neutrophils and MHC II+ antigen-presenting cells located in the intraepithelial and subepithelial areas of conducting airways.

Results

Allergen challenge induced transient neutrophil recruitment to the airways. Application of A. fumigatus conidia at the acute phase of AAI provoked recurrent neutrophil infiltration, and consequently increased the number and the ingestion potential of the airway neutrophils. In the absence of recurrent allergen or conidia provocation, both the ingestion potential and the number of BAL neutrophils decreased. As a result, conidia were primarily internalized by alveolar macrophages in both AAI and control mice at 24 hours post-inhalation. Transient influx of neutrophils to conducting airways shortly after conidial application was observed in mice with AAI. In addition, the ingestion potential of conducting airway neutrophils in mice with induced asthma exceeded that of control mice. Although the number of neutrophils subsequently decreased, the ingestion capacity remained elevated in AAI mice, even at 24 hours post-conidia application.

Conclusions

Aspiration of allergen to sensitized mice enhanced the ingestion potential of conducting airway neutrophils. Such activation primes neutrophils so that they are sufficient to control dissemination of non-germinating A. fumigatus conidia. At the same time, it can be a reason for the development of sensitivity to fungi and subsequent asthma exacerbation.  相似文献   
80.
Cell migration is fundamental to many biological processes, including development, normal tissue remodeling, wound healing, and many pathologies. However, cell migration is a complex process, and understanding its regulation in health and disease requires the ability to manipulate and measure this process quantitatively under controlled conditions. This report describes a simple in vitro assay for quantitative analysis of cell migration in two-dimensional cultures that is an inexpensive alternative to the classic “scratch” assay. The method described utilizes flexible silicone masks fabricated in the lab according to the research demands of the specific experiment to create a cell-free area for cells to invade, followed by quantitative analysis based on widely available microscopic imaging tools. This experimental approach has the important advantage of visualizing cell migration in the absence of the cellular damage and disruption of the substrate that occurs when the “wound” is created in the scratch assay. This approach allows the researcher to study the intrinsic migratory characteristics of cells in the absence of potentially confounding contributions from cellular responses to injury and disruption of cell–substrate interactions. This assay has been used with vascular smooth muscle cells, fibroblasts, and epithelial cell types, but should be applicable to the study of practically any type of cultured cell. Furthermore, this method can be easily adapted for use with fluorescence microscopy, molecular biological, or pharmacological manipulations to explore the molecular mechanisms of cell migration, live cell imaging, fluorescence microscopy, and correlative immunolabeling.  相似文献   
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