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81.
ZL Gokaslan JE York GL Walsh IE McCutcheon FF Lang JB Putnam DM Wildrick SG Swisher D Abi-Said R Sawaya 《Canadian Metallurgical Quarterly》1998,89(4):599-609
Protein kinase C is an important second messenger system, which is translocated from the cytosol to the cell membrane upon cell stimulation. We used confocal microscopy to study the spatial distribution of protein kinase C isoforms after stimulation of cultured vascular smooth muscle cells with different agonists. First, we analysed the effects of angiotensin II and platelet-derived growth factor (PDGF). Confocal microscopy showed a rapid assembly of PKC alpha along cytosolic fibres followed by a translocation towards the nucleus with angiotensin II. PDGF engendered a similar, but much slower response; however, a cytoskeletal distribution was not observed. We then investigated the effects of thrombin and bFGF on nuclear translocation. bFGF induced a rapid translocation of the isoform towards the perinuclear region and into the nucleus. bFGF had a similar effect on PKC epsilon. In contrast, thrombin had a smaller effect on nuclear translocation of PKC alpha and did not influence PKC epsilon, but instead induced a rapid nuclear translocation of PKC zeta. Thus, tyrosine kinase receptor activation via bFGF induces a rapid association of PKC alpha and epsilon within nuclear structures. Our results show that agonists cause, not only a translocation of protein kinase C isoforms into the cell membrane but also into the cell nucleus. Lastly, we analyzed the nuclear immunoreactivity of the PKC isoforms, alpha, delta, epsilon and zeta in vascular smooth muscle cells during the cell cycle. Resting cells were stimulated with foetal calf serum (FCS, 10%), which translocated PKC alpha and epsilon to the perinuclear region and into the nucleus, while PKC delta and zeta showed no increase in nuclear immunoreactivity. After 4 h of FCS, the nuclear immunoreactivity for PKC alpha and epsilon was reduced to or below control values. At 8 h, increased nuclear expression of isoforms alpha, epsilon and zeta was observed, while isoform delta was not affected. Our results demonstrate a complex spatial and temporal regulation of PKC isoforms in response to vasoactive hormones and growth factors. We suggest that protein kinase C may be important for nuclear signaling and demonstrate that nuclear translocation of PKC isoforms is differentially regulated during the cell cycle. 相似文献
82.
IE Aradaib WC Wilson CE Schore ME Mohammed TD Yilma JS Cullor BI Osburn 《Canadian Metallurgical Quarterly》1998,36(9):2604-2608
PCR amplification technology for the detection of epizootic hemorrhagic disease virus (EHDV) ribonucleic acid in cell culture and clinical specimens was developed. With oligoribonucleotide primers selected from genome segment 10 of EHDV serotype 1 (EHDV-1), which codes for two nonstructural proteins (NS3 and NS3a), the PCR-based assay resulted in a 535-bp PCR product. RNAs from North American EHDV-1 prototype, EHDV-2 prototype, and a number of EHDV field isolates, including the Central African isolates of EHDV-5 and EHDV-318 propagated in cell cultures, were detected by this PCR-based assay. The specific 535-bp PCR products were visualized onto agarose gels, and the identity of the PCR products was confirmed by chemiluminescent hybridization with a 352-bp internal probe. The sensitivity of the EHDV PCR assay was increased by chemiluminescent hybridization; by this EHDV-NS3 PCR, 10 fg of EHDV RNA was detected (equivalent to 600 viral particles). Amplification product was not detected when the PCR-based assay was applied to RNAs from North American bluetongue virus prototype serotypes 2, 10, 11, 13, and 17; total nucleic acid extracts from uninfected BHK-21 cells; or unfractionated blood from calves and deer that were EHDV seronegative and virus isolation negative. The described EHDV PCR-based assay with primers derived from segment 10 of EHDV-1 resulted in detection of EHDV RNA from blood and tissues collected from calves and deer with natural and experimental EHDV infections and provides a valuable tool to study the epidemiology of EHDV infection in susceptible ruminants. 相似文献
83.
84.
The use of primary chemotherapy represents a novel approach being used with increasing frequency in the management of early breast cancer. Many studies now testify to the usefulness of this modality in increasing the frequency of breast conservation. The acceptance of high-risk breast cancer as a systemic, and therefore predominantly medical rather than a surgical, disease suggests, however, that its role is likely to be far more reaching. While some trials have so far suggested the possibility of a survival benefit for this approach, definitive conclusions are not yet possible and await the final mature results from several large randomized studies. Even if such studies do not show a large extra benefit for primary chemotherapy over existing adjuvant treatment, the use of the primary tumour as an in vivo model of individual chemosensitivity and the identification of molecular markers as early predictors of response, suggest that this approach will become an integral part of the modern multidisciplinary management of early breast cancer. 相似文献
85.
In the past, urologic complications contributed greatly to spinal cord injury mortality. With improved evaluation and treatment, this is no longer the case. Treatment should be guided by urodynamic data gathered after the resolution of spinal shock symptoms. Goals of treatment are to facilitate voiding, reduce incontinence, and prevent renal damage. Indwelling catheters are almost never indicated for long-term treatment of the neurogenic bladder. Commonly used treatments include intermittent catheterization, condom catheter drainage with sphincter ablation, and pharmaceutical manipulation. Electrical stimulation of sacral nerve roots shows promise for future therapy. 相似文献
86.
The authors have studied the process of revascularization of free transplants of growth zones of the bones transplanted heterotopically from greater trochanter of the femur onto the chest. The X-ray and histological data have shown the ingrowth of the vessels into autotransplants from the side of soft tissues of the recipient bed responsible for the growth of the epiphyseal cartilage. 相似文献
87.
88.
IE Nygaard 《Canadian Metallurgical Quarterly》1998,25(4):867-882
Pharmacologic therapy is an important part of the treatment armamentarium for urogynecologic disorders. Current and future research will determine the utility of such therapy as medications with fewer side effects and more targeted efficacy are developed. 相似文献
89.
90.