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71.
Fibroblast dynamics as an in vitro screening platform for anti‐fibrotic drugs in primary myelofibrosis 下载免费PDF全文
Ciprian Tomuleasa MD PhD Sonia Selicean MD Grigore Gafencu MD Bobe Petrushev MD Laura Pop PhD Cristian Berce PhD Anca Jurj PhD Adrian Trifa MD PhD Ana‐Maria Rosu MD Sergiu Pasca MD Lorand Magdo MD Mihnea Zdrenghea MD PhD Delia Dima MD PhD Alina Tanase MD PhD Ioana Frinc MD Anca Bojan MD Ioana Berindan‐Neagoe PhD Gabriel Ghiaur MD PhD Stefan O. Ciurea MD 《Journal of cellular physiology》2018,233(1):422-433
Although the cause for bone marrow fibrosis in patients with myelofibrosis remains controversial, it has been hypothesized that it is caused by extensive fibroblast proliferation under the influence of cytokines generated by the malignant megakaryocytes. Moreover, there is no known drug therapy which could reverse the process. We studied the fibroblasts in a novel system using the hanging drop method, evaluated whether the fibroblasts obtain from patients are part of the malignant clone of not and, using this system, we screen a large library of FDA‐approved drugs to identify potential drugs candidates that might be useful in the treatment of this disease, specifically which would inhibit fibroblast proliferation and the development of bone marrow fibrosis. We have found that the BM fibroblasts are not part of the malignant clone, as previously suspected and two immunosuppressive medications—cyclosporine and mycophenolate mophetil, as most potent suppressors of the fibroblast collagen production thus potentially inhibitors of bone marrow fibrosis production in myelofibrosis. 相似文献
72.
G. Sanna Passino E. Bazzoni MD L. Moretti R. Prota 《Journal of Applied Entomology》1999,123(3):145-149
The effects on adult Ceratitis capitata of the ingestion of formulations containing different concentrations of some essential oils were examined. The bioassays were carried out using groups of C. capitata adults fed for 3 days with formulations containing a known concentration (0.25%, 0.5%, 1.0%) of essential oils. The oils, of different chemical composition, were obtained by steam distillation from aromatic plants collected during the balmy period. The essential oils of Rosmarinus officinalis and Salvia officinalis , which are rich in monoterpenic hydrocarbons and monoterpenic ketones, respectively, showed poor activity, whereas the oils of Cinnamomum zeylanicum and Thymus sp. showed a marked toxic effects (over 90% mortality after 72 h). This could be explained by the activity of cinnamic aldehyde (about 80% of the Cinnamomum oil) and carvacrol (68% of Th. capitatus oil and about 45% of Th. herba barona oil). The first consequence of ingesting even small quantities of essential oils was a depressive effect on the nervous system. Dissection of dead flies showed marked differences compared with the controls and microscopic examination revealed anomalies in the gut region. 相似文献
73.
B. A. Cowell MD P. Willcox B. Herbert R. P. Schneider 《Journal of applied microbiology》1999,86(6):944-954
Pseudomonas aeruginosa causes a variety of diseases in humans including lung and ocular infections. Infections of the cornea are usually associated with wearing contact lenses and can result in loss of vision. This study aimed to determine the effect of carbon or nitrogen limitation on the adhesion to contact lenses of a strain of Ps. aeruginosa isolated from contact lens-related corneal inflammation. Cells were grown in a continuous culture apparatus in varying levels of glucose or ammonia to effect nutrient limitation. Adhesion to contact lenses was measured as total counts and viable counts. The cell surface hydrophobicity and charge were measured using adhesion to surface-modified Sepharose. Changes in lipopolysaccharide were determined using 1D SDS-PAGE and changes in cell-surface proteins were measured using 2D gel electrophoresis. The more the cultures were nitrogen limited, the greater the increase in adhesion to unworn hydrogel contact lenses 0.3 x 10(3) - 2.2 x 10(3) cells/mm2 on Etafilon A lenses. Cells that were carbon limited showed a greater increase in adhesion to contact lenses when the lenses had been coated in artificial tears. It appeared that lipopolysaccharide may have been involved in the constitutive adhesion to unworn lenses that occurred during C-limitation, whereas changes in the outer membrane proteins contributed to the increased adhesion under nitrogen limitation, or the change in adhesion that occurred to carbon-limited cells using contact lenses coated in artificial tears. Nine cell-surface proteins appeared during nitrogen limitation with kDa/pI of 75/4.8, 4.9, 5.0; 62/5.6; 89/6.5; 38/6.4; 28/1.5; 18/6.4; 12/4.5. Any or all of these may have been involved in the increased adhesion and further experiments are underway to examine this possibility. 相似文献
74.
Tsan Liu Arnold Stern L. Jackson Roberts Jason D. Morrow MD 《Journal of biomedical science》1999,6(4):226-235
The isoprostanes (IsoPs) are a unique series of prostaglandin-like compounds formed in vivo from the free radical-catalyzed peroxidation of arachidonic acid. This review summarizes our current knowledge regarding these compounds. Novel aspects of the biochemistry and bioactivity of IsoPs are detailed and methods by which these compounds are analyzed are discussed. A considerable portion of this review deals with the utility of measuring IsoPs as markers of oxidant injury in human diseases particularly in association with risk factors that predispose to atherosclerosis, a condition in which excessive oxidative stress has been causally implicated. 相似文献
75.
Eight Danish Holstein cows were milked with a 1-mm thick specially designed soft liner on their right rear teat and a standard
liner mounted under extra high tension on their left rear teat. Four of the animals were overmilked for 5 min. Rear teats
were subjected to ultrasound examination on the first day and to infrared thermography on the second day. Teats were submersed
in ethanol 20 min post-milking on the second day. Ultrasonography measurements showed that teat canal length increased by
30–41% during milking. Twenty minutes after milking, teats milked with modified standard liners still had elongated teat canals
while teats milked with the soft liner were normalized. Overmilking tended to increase teat wall thickness. Approximately
80% of variability in teat canal length, from before teat preparation to after milking, could be explained by changes during
teat preparation. Thermography indicated a general drop in teat temperature during teat preparation. Teat temperature increased
during milking and continued to increase until the ethanol challenge induced a significant drop. Temperatures approached pre-challenge
rather than pre-milking temperatures within 10 minutes after challenge. Teat temperatures were dependent on type of liner.
Mid-teat temperatures post-challenge relative to pre-teat preparation were dependent on overmilking. Thermography and ultrasound
were considered useful methods to indirectly and non invasively evaluate teat tissue integrity. 相似文献
76.
77.
Effects of pH and predation by Chaoborus larvae on the plankton of a shallow and acidic forest lake 总被引:1,自引:0,他引:1
1. Eutrophic acid lakes are not common. Delamere Lake in Cheshire, U.K. is shallow and acid (mean pH 4.5) with a very high phytoplankton crop (mean 290 μg chlorophyll a L?1), dominated by Dictyosphaerium pulchellum. Rotifers were dominant in the pelagic waters but small cladocerans (Alona guttata, Chydorus sphaericus and Scapholeberis mucronata) were occasional in the littoral waters. Chaoborus flavicans larvae were the top predators in this fishless lake. Two mesocosm experiments were carried out in which pH and Chaoborus populations were manipulated. 2. Progressively higher concentrations of D. pulchellum were maintained in the elevated pH treatments (pH 6 and 8; P < 0.001) with increased amounts of a Chlamydomonas species at the end of the experiment. Highest species richness was seen at ambient pH. Thus the low pH of Delamere Lake alone did not control the structure of the phytoplankton community. Keratella quadrata showed significantly higher abundance at pH 6 than in other pH treatments (P < 0.001). Species richness of rotifers was unaffected by pH. 3. Most Cladocera were C. sphaericus. Although never seen in the open lake, Daphnia pulex appeared in all the pH treatments. Low pH did not control small Cladocera abundance in Delamere Lake, but probably hampered reproduction in Daphnia. Negative correlations between chlorophyll a concentrations and Daphnia in the mesocosms (r2 = 0.215, P < 0.05), however, indicated the potential of large‐bodied daphniids in controlling phytoplankton. 4. Neither different combinations of Chaoborus instars (none, instars 1 and 2 and instars 3–5) nor different densities of instars 3–5 (0.15, 0.5 and 1.0 L?1) had a negative impact on Cladocera. Daphnia pulex remained unaffected in the experiment, perhaps because of its large size, and C. sphaericus because of its high reproductive rate compensating predatory losses. 5. Very low pH in Delamere Lake might suppress Daphnia by hampering its reproduction. Consequently, Daphnia may be vulnerable to invertebrate predation even at low predator density in the lake. 相似文献
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The study included 24 cases of negative second-look laparotomy (SLL) after operation on ovarian cancer. 12 cases were treated with sizofiran and recombinant interferon-gamma before and after SLL and then with human lymphoblastoid interferon-alpha. The remaining 12 cases (controls) were followed up without any drug therapy after SLL. There were no recurrences in the treated group, but in 3 cases of the control group. Also significant difference in survival was noted in the treated group. 相似文献