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101.
In the event of smallpox bioterrorism, widespread vaccination may be required. Vaccinia immune globulin (VIG) has been used to treat complications from the smallpox vaccine. While the potency of VIG was defined by its ability to neutralize intracellular mature virus, a second form of vaccinia called the extracellular enveloped virus (EEV) is critical for virus spread in the host. The B5R-protein is one of many EEV-specific proteins. Immunoprecipitation and ELISA revealed that VIG recognizes the B5R-protein. An EEV plaque-reduction assay using a recombinant vaccinia that lacks the majority of the extracellular domain of B5R showed that the ability of VIG to neutralize EEV is principally directed at B5R. In addition, absorbing out the anti-B5R antibody present in VIG through the addition of recombinant B5R protein abrogated VIG's ability to significantly neutralize wild-type EEV. This work demonstrates the prominent role of B5R as a target of EEV-neutralizing activity of human antibodies.  相似文献   
102.
Mesothelial/monocytic incidental cardiac excrescence (MICE) is a very uncommon lesion. Diagnosis is incidental and may simulate thrombotic lesions. One of the hypotheses with regard to the etiology of this lesion is a previous cardiac procedure especially mitral valve repair or commissurotomy. Herein, we describe a MICE incidentally found in a patient who underwent mitral valve replacement, as a thrombotic lesion on the left atrial auricle. Histopathologic examination suggested MICE lesions and immunohistochemical stains confirmed it.  相似文献   
103.
The cellular receptor for urokinase-type plasminogen activator receptor (uPAR) is a member of the glycosylphosphatidylinositol (GPI) anchored protein family. It is a specific cell surface receptor for its ligand, urokinase-type plasminogen activator, which catalyzes the formation of plasmin from plasminogen to generate the proteolytic cascade and leads to the breakdown of the extracellular matrix. uPAR has been shown to correlate with a propensity to tumor invasion and metastasis in several types of non-central nervous system tumors. In this study, the authors examined the immunohistochemical expression of uPAR in 65 primary brain tumors (5 pilocytic astrocytomas, 5 diffuse astrocytomas, 6 anaplastic astrocytomas, 8 glioblastomas, 5 oligodendrogliomas, 4 oligoastrocytomas, 6 anaplastic oligoastrocytomas, 4 gangliogliomas, 4 ependymomas, 5 medulloblastomas, 6 schwannomas, 5 meningiomas, 2 atypical meningiomas). The specimens were evaluated for intensity of immunostaining (0-3 scale), cellular localization of staining, and specific or unique patterns of staining. Some degree of uPAR expression was observed in all tumors. A significant positive correlation (P = 0.0006) between tumor grade and staining intensity was identified within the astrocytoma/glioblastoma subgroup, suggesting a possible correlation with anaplastic change and propensity to tumor invasion. Expression of uPAR in nonmalignant, noninvasive tumors such as schwannoma and meningioma suggests that uPAR may have other biologic functions in addition to promotion of tumor invasion.  相似文献   
104.
The problem of morphine tolerance and dependence is a universal phenomenon threatening social health everywhere the world. The major objective of this paper was to investigate the effects of fruit essential oil (FEO) of Cuminum cyminum on acquisition and expression of morphine tolerance and dependence in mice. Animals were rendered dependent on morphine using the well-established method in which was morphine (50, 50, 75 mg/kg; s.c.) injected three times daily for 3 days. In experimental groups, administration of FEO (0.001, 0.01, 0.1, 0.5, 1 and 2%; 5 ml/kg; i.p.) or Tween-80 (5 ml/kg; i.p.) was performed 60 min prior to each morphine injection (for acquisition) or the last injection of morphine on test day (for expression). Morphine tolerance was measured by tail-flick before and after administration of a single dose of morphine (50 mg/kg; s.c.) in test day (4th day). Morphine dependence was also evaluated by counting the number of jumps after injection of naloxone (5 mg/kg; i.p.) on the test day. The results showed that Cumin FEO, only at the dose of 2%, significantly attenuated the development of morphine tolerance (P < 0.01) and dependence (P < 0.05) while it could be significantly effective on expression of morphine tolerance (1 and 2%) and dependence (0.5, 1 and 2%) in a dose-dependent manner. Solely Cumin FEO injection (0.001–2%) did not show any analgesic effect. In conclusion, the essential oil of Cuminum cyminum seems to ameliorate the morphine tolerance and dependence in mice.  相似文献   
105.
The objective of this study is to design a new apparatus to allow the control of the magnitude and frequency of dynamic stretch applied uniformly to cells cultured on a silicon elastic membrane. The apparatus is designed to produce equi-biaxial dynamic stretches with area changes ranging from 0% to 55% and frequencies ranging from 0 to 2 Hz. Homogeneous finite strain analysis using triangles of markers was performed to compute the symmetric two-dimensional Lagrangian strain tensor on the membrane. Measurements of strain in both static and dynamic conditions showed that the shear component of the strain tensor (Erc) was near zero, and that there was no significant difference between radial (Err) and circumferential (Ecc) components, indicating the attainment of equi-biaxial strain. Bovine aortic endothelial cells were transiently transfected with a chimeric construct in which the luciferase reporter is driven by TPA-responsive elements (TRE). The transfected cells cultured on the membrane were stretched. The luciferase activity increased significantly only when the cells were stretched by 15% or more in area. Cells in different locations of the membrane showed similar induction of luciferase activities, confirming that strain is uniform and equi-biaxial across the membrane. © 1998 Biomedical Engineering Society. PAC98: 8780+s, 8745-k, 8722-q  相似文献   
106.
107.
Somatic mitochondrial mutations are common in human cancers, and can be used as a tool for early detection of cancer. We have developed a mitochondrial Custom Reseq microarray as an array-based sequencing platform for rapid and high-throughput analysis of mitochondrial DNA. The MitoChip contains oligonucleotide probes synthesized using standard photolithography and solid-phase synthesis, and is able to sequence >29 kb of double-stranded DNA in a single assay. Both strands of the entire human mitochondrial coding sequence (15,451 bp) are arrayed on the MitoChip; both strands of an additional 12,935 bp (84% of coding DNA) are arrayed in duplicate. We used 300 ng of genomic DNA to amplify the mitochondrial coding sequence in three overlapping long PCR fragments. We then sequenced >2 million base pairs of mitochondrial DNA, and successfully assigned base calls at 96.0% of nucleotide positions. Replicate experiments demonstrated >99.99% reproducibility. In matched fluid samples (urine and pancreatic juice, respectively) obtained from five patients with bladder cancer and four with pancreatic cancer, the MitoChip detected at least one cancer-associated mitochondrial mutation in six (66%) of nine samples. The MitoChip is a high-throughput sequencing tool for the reliable identification of mitochondrial DNA mutations from primary tumors in clinical samples.  相似文献   
108.
The role of COX-2 in angiogenesis and rheumatoid arthritis   总被引:4,自引:0,他引:4  
Recent evidence suggests that cyclooxygenase (COX)-2 is a mediator of angiogenesis, and COX-2 activity is known to be upregulated in the rheumatoid arthritis (RA) synovium. We examined whether mediation of angiogenesis by COX-2 was occuring in cells of the RA synovium and in microvascular endothelial cells (ECs) that are similar to those found in the RA synovium. We demonstrate that rofecoxib, a selective COX-2 inhibitor, acts directly on human dermal microvascular ECs (HMVECs) to inhibit their chemotactic and tube forming ability. Likewise, pretreatment of HMVECs with rofecoxib significantly inhibited their ability to form tubes induced by conditioned media (CM) of activated RA synovial fibroblasts. When RA synovial fibroblasts were pretreated with rofecoxib for 16 h and then stimulated with interleukin (IL)-1beta, their CM induced significantly less HMVEC tube formation when compared with CM from vehicle-treated RA synovial fibroblasts. ELISAs performed on activated RA fibroblast CM for known proangiogenic factors demonstrated a significant reduction in bFGF, in addition to the expected decrease in PGE(2). Our studies suggest that COX-2-induced angiogenic activity is an active mechanism within diseased synovium and may provide an additional rationale for the use of COX-2 inhibitors in RA.  相似文献   
109.
Fine-needle aspiration biopsy findings in three cases of chromophobe cell carcinoma are described and correlated with histologic and ultrastructural observations. In addition, comparisons are made with three cases each of oncocytoma and granular cell carcinoma. The cells in aspiration smears from chromophobe cell carcinoma closely correlated with histologic pattern of three cell types which were not present in oncocytomas and granular cell carcinomas. These cells had prominent cell borders, and their cytoplasm was either opaque and granular (type I) or variably translucent and reticular (type II and III). Ultrastructurally, the translucent areas within the cytoplasm contained large numbers of microvesicles which were unique to chromophobe cell carcinoma and were not seen in other neoplasms. Fine-needle aspiration may be used to diagnose chromophobe cell carcinoma and distinguish it from other related renal neoplasms. © 1995 Wiley-Liss, Inc.  相似文献   
110.
Atherosclerosis (AR) is the leading cause of morbidity and mortality in the US and cigarette smoking is a major contributing factor to the disease. Like cigarette smoking in lung cancer, genetic susceptibility may be an important factor in determining who is more likely to develop AR. However, the current emphasis has been on susceptibility based on altered cardiovascular homeostasis. In this investigation, we studied 120 AR patients and 90 matched controls to elucidate the association between polymorphisms in some metabolizing genes (GSTM1, GSTT1, CYP2E1, mEH, PON1, and MPO) and susceptibility to AR. We found that the GSTT1 null allele and the fast allele of mEH(*) (exon 4) are associated with risk for AR. Furthermore, the combined genotypes GSTM1 null/ CYP2E1(*)5B, GSTM1 null/mEH YY, and GSTT1 null/mEH YY are significantly associated with susceptibility to AR (OR = 15.42, 95% CI = 1.33-77.93, P = 0.021; OR = 3.48, 95% CI = 1.63-8.04, P = 0.0008; OR = 3.4; 95% CI = 0.99-17.38, P = 0.05; respectively). We have also conducted cytogenetic analysis to elucidate if induction of chromosome aberrations (CAs) is a biomarker of AR susceptibility. We found that among cigarette smokers (AR patients and smoker controls), individuals having the GSTM1 null allele had a significantly higher frequency of CAs compared to those with the normal allele (P < 0.05). This association was not found among nonsmokers. In addition, individuals who had inherited the CYP2E1(*)5B allele exhibited a significantly higher CA frequency (8.0 +/- 0.82) compared to those with the CYP2E1 wild-type genotype (4.31 +/- 0.35). Since the analysis of genetic susceptibility factors is still in its infancy, our study may stimulate additional investigations to understand the roles of genetic susceptibility and cigarette smoking in AR.  相似文献   
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