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71.
Hematopoietic-specific microRNA expression in human cells   总被引:7,自引:0,他引:7  
We examined expression profiles of hematopoietic tissue-specific microRNAs (miRNAs; miR-142, miR-155, miR-181 and miR-223) in 17 commercially available malignant hematopoietic cell lines and compared to those in highly purified normal human B, T, monocytic and granulocytic lineages. Although malignant cell lines examined showed miRNA expression patterns similar to normal human hematopoietic lineages, the levels of miRNA expression among cell lines and normal cell lineages were considerably different, indicating the significance of miRNAs in human hematopoietic diseases. Further our results showed differences in miRNA expression between mouse and human hematopoietic cells, suggesting important regulatory roles of miRNAs in human hematopoiesis and oncogenesis.  相似文献   
72.

Background

Medical Termination of Pregnancy (MTP) is a commonly performed during the first trimester. Dilatation and Evacuation (D & E) mandates rapid dilatation of cervix with metal dilators, which requires anaesthesia and may be associated with trauma to the uterus, cervix and later cervical incompetence. The problem of rapid cervical dilatation is obviated with intravaginal misoprostol.

Methods

Intravaginal misoprostol tablet 200 microgram was inserted, a night prior to MTP to ripen the cervix. Cervix was dilated with metal dilators only in cases where cervix did not loosen up sufficiently. Products of conception were removed by suction.

Results

Out of 108 cases cervical dilatation was not required in 96 cases (88.9%).

Conclusion

Intravaginal misoprostol 200 microgram proved effective as a priming agent prior to MTP in the first trimester.Key Words: Misoprostol, MTP  相似文献   
73.
Despite intensive therapy, ~60–80% of children who are diagnosed with metastatic neuroblastoma (NB) succumb to the disease. NB preferentially metastasizes to the bone marrow (BM). In the present study we used SY5Y and CHP212 (NB cell lines) to study the roles of the preprotachykinin-I (PPT-I) gene and the natural receptors for PPT-I peptides, neurokinin-1 (NK-1) and NK-2, in the biology of NB. PPT-I, NK-1 and NK-2 were constitutively expressed in the NB cells. Functional studies, with specific NK receptor antagonists, showed that PPT-I peptides mediate autocrine proliferation of the NB cells through both NK-1 and NK-2 receptors. Full-length and truncated NK-1 receptors were detected in NB cells. Since there is one copy of the NK-1 gene, we used NK-1-specific siRNA to suppress the expression of NK-1. The NK-1-deficient NB cells showed phenotypes consistent with cell differentiation. Suppression of NK-1 did not appear to cause cell death, as demonstrated by trypan blue exclusion and by undetectable active caspase. NK-1 suppression reduced the proliferation of the NB cells beginning by 10-fold at day 1 and reached a 105-fold reduction by day 10. The NK-1 deficient cells did not proliferate when they were placed as cocultures with BM stroma, which suggests that NK-1 signaling is important for the survival of NB cells in the BM. The results show potential roles for NK receptors in the proliferation of NB.  相似文献   
74.
75.
We present the different imaging modalities in relation to myeloma, ranging from the time tested X-ray radiography to the newer promising methods of fluorine-18 fluorodesoxyglucose-positron emission tomography ((18)F-FDG-PET) and technetium-99m methoxy isobutyl isonitrite ((99m)Tc-MIBI) scintigraphy. A small discussion regarding newer methods such as fluoride-18 positron emission tomography ((18)F-PET), fluorine-18-fluoro-deoxy-L-thymidine positron emission tomography ((18)F-FLT PET), carbon-11 methionine positron emission tomography ((11)C-methionine PET) and the tritiated thymidine labeling index is also included. They have different mechanisms of tracer uptake enabling the visualization of the spectrum of the disease manifestations ranging from osteoblastic to osteolytic lesions, and also the study of the metabolic status, proliferative and protein activity, in skeletal and in extra-skeletal sites.  相似文献   
76.
77.
Background/Aims:We evaluated the impact of the initial intravenous fluid resuscitation rate within the first 24 h of presentation to the emergency room on important outcomes in severe acute pancreatitis. Methods: Patients presenting directly with a diagnosis of severe acute pancreatitis were identified retrospectively. Patients were divided into two groups — those who received ≥.33% (‘early resuscitation’) and <33% (‘late resuscitation’) of their cumulative 72-hour intravenous fluid volume within the first 24 h of presentation.The primary clinical outcomes were in-hospital mortality, development of persistent organ failure, and duration of hospitalization. Results: 17 patients were identified in the ‘early resuscitation’ group and 28 in the ‘late resuscitation’ group and there were no baseline differences in clinical characteristics between groups. Patients in the ‘late resuscitation’ group experienced greater mortality than those in the ‘early resuscitation’ group (18 vs. 0%,p<0.04) and demonstrated a trend toward greater rates of persistent organ failure (43 vs. 35%, p = 0.31). There was no difference in the total amount of fluid given during the first 72 h. Conclusions: Patients with severe acute pancreatitis who do not receive at least one third of their initial 72-hour cumulative intravenous fluid volume during the first 24 h are at riskfor greater mortality than those who are initially resuscitated more aggressively.  相似文献   
78.
The past decade has seen momentous development in brain cancer research in terms of novel imaging-assisted surgeries, molecularly targeted drug-based treatment regimens or adjuvant therapies and in our understanding of molecular footprints of initiation and progression of malignancy. However, mortality due to brain cancer has essentially remained unchanged in the last three decades. Thus, paradigm-changing diagnostic and therapeutic reagents are urgently needed. Nanotheranostic platforms are powerful tools for imaging and treatment of cancer. Multifunctionality of these nanovehicles offers a number of advantages over conventional agents. These include targeting to a diseased site thereby minimizing systemic toxicity, the ability to solubilize hydrophobic or labile drugs leading to improved pharmacokinetics and their potential to image, treat and predict therapeutic response. In this article, we will discuss the application of newer theranostic nanoparticles in targeted brain cancer imaging and treatment.  相似文献   
79.

Background and purpose:

9,10-Dihydro-2,5-dimethoxyphenanthrene-1,7-diol (RSCL-0520) is a phenanthrene isolated from Eulophia ochreata, one of the Orchidaceae family, known by local tradition to exhibit medicinal properties. However, no anti-inflammatory activity or any molecular mechanisms involved have been reported or elucidated. Here, for the first time, we evaluate the anti-inflammatory properties of RSCL-0520 on responses induced by lipopolysaccharide (LPS) and mediated via Toll-like receptors (TLRs).

Experimental approach:

The in vitro anti-inflammatory activities of RSCL-0520 were investigated in LPS-stimulated monocytic cells, measuring activation of cytokine and inflammatory genes regulated by nuclear factor-κB (NF-κB). Tumour necrosis factor (TNF)-α levels in serum following LPS stimulation in mice and carrageenan-induced paw oedema in rats were used as in vivo models.

Key results:

Pretreatment with RSCL-0520 effectively inhibited LPS-induced, TLR4-mediated, NF-κB-activated inflammatory genes in vitro, and reduced both LPS-induced TNF-α release and carrageenan-induced paw oedema in rats. Treatment with RSCL-0520 reduced LPS-stimulated mRNA expression of TNF-α, COX-2, intercellular adhesion molecule-1, interleukin (IL)-8 and IL-1β, all regulated through NF-κB activation. RSCL-0520, however, did not interfere with any cellular processes in the absence of LPS.

Conclusions and implications:

RSCL-0520 blocked signals generated by TLR4 activation, as shown by down-regulation of NF-κB-regulated inflammatory cytokines. The inhibitory effect involved both MyD88-dependent and -independent signalling cascades. Our data elucidated the molecular mechanisms involved, and support the search for plant-derived TLR antagonists, as potential anti inflammatory agents.  相似文献   
80.
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