181 research outputs found
ENHANCED ERYTHROPOIESIS WITH CONCOMITANT DIMINISHED GRANULOPOIESIS IN PREIRRADIATED RECIPIENT MICE : EVIDENCE FOR A COMMON STEM CELL
Three different methods of measuring the proliferative capacity of transplanted mouse bone marrow were used to study the effects of preirradiation of the recipient. Recipient mice were exposed to 700 R and given graded numbers of syngeneic bone marrow. 7 days were allowed for proliferation of these cells, and then the granulocytic or erythrocytic progeny was measured. The former was determined by the response to endotoxin, and the latter by the incorporation of radioactive iron into newly formed red blood cells. Erythropoiesis, therefore, could be measured independently from granulopoiesis by these techniques. The third method used was the spleen colony method of Till and McCulloch (5). Recipient animals exposed to 150 R preirradiation, 7 days before 700 R and bone marrow transplantation, demonstrated an increase in erythropoiesis with a concommittant decrease in granulopoiesis compared to similar recipients not preirradiated. The spleen colony technique showed that while the number of colonies were the same in both groups, the colonies themselves were significantly larger in the preirradiated animals. Since such colonies are primarily erythropoietic, this finding is consistent with the other methods. The results can be explained by assuming the presence of a hematopoietic stem cell which, in these preirradiated recipients, is directed towards erythropoiesis at the expense of granulopoiesis
Effects of Optical Turbulence and Density Gradients On Particle Image Velocimetry
Particle image velocimetry (PIV) is a well-established tool to collect high-resolution velocity and turbulence data in the laboratory, in both air and water. Laboratory experiments are often performed under conditions of constant temperature or salinity or in flows with only small gradients of these properties. At larger temperature or salinity variations, the changes in the index of refraction of water or air due to turbulent microstructure can lead to so-called optical turbulence. We observed a marked influence of optical turbulence on particle imaging in PIV. The effect of index of refraction variations on PIV has been described in air for high Mach number flows, but in such cases the distortion is directional. No such effect has previously been reported for conditions of isotropic optical turbulence in water. We investigated the effect of optical turbulence on PIV imaging in a large Rayleigh-BĂ©nard tank for various path lengths and turbulence strengths. The results show that optical turbulence can significantly affect PIV measurements. Depending on the strength of the optical turbulence and path length, the impact can be mitigated in post-processing, which may reduce noise and recover the mean velocity signal, but leads to the loss of the high-frequency turbulence signal
Evidence for topological surface states in amorphous BiSe
Crystalline symmetries have played a central role in the identification of
topological materials. The use of symmetry indicators and band representations
have enabled a classification scheme for crystalline topological materials,
leading to large scale topological materials discovery. In this work we address
whether amorphous topological materials, which lie beyond this classification
due to the lack of long-range structural order, exist in the solid state. We
study amorphous BiSe thin films, which show a metallic behavior and
an increased bulk resistance. The observed low field magnetoresistance due to
weak antilocalization demonstrates a significant number of two dimensional
surface conduction channels. Our angle-resolved photoemission spectroscopy data
is consistent with a dispersive two-dimensional surface state that crosses the
bulk gap. Spin resolved photoemission spectroscopy shows this state has an
anti-symmetric spin-texture resembling that of the surface state of crystalline
BiSe. These experimental results are consistent with theoretical
photoemission spectra obtained with an amorphous tight-binding model that
utilizes a realistic amorphous structure. This discovery of amorphous materials
with topological properties uncovers an overlooked subset of topological matter
outside the current classification scheme, enabling a new route to discover
materials that can enhance the development of scalable topological devices.Comment: 40 pages (21 main + 19 supplemental), 15 figures (4 main + 11
supplemental
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Oligo- and Polymetastatic Progression in Lung Metastasis(es) Patients Is Associated with Specific MicroRNAs
Rationale: Strategies to stage and treat cancer rely on a presumption of either localized or widespread metastatic disease. An intermediate state of metastasis termed oligometastasis(es) characterized by limited progression has been proposed. Oligometastases are amenable to treatment by surgical resection or radiotherapy.Methods: We analyzed microRNA expression patterns from lung metastasis samples of patients with ≤5 initial metastases resected with curative intent.Results: Patients were stratified into subgroups based on their rate of metastatic progression. We prioritized microRNAs between patients with the highest and lowest rates of recurrence. We designated these as high rate of progression (HRP) and low rate of progression (LRP); the latter group included patients with no recurrences. The prioritized microRNAs distinguished HRP from LRP and were associated with rate of metastatic progression and survival in an independent validation dataset.Conclusion: Oligo- and poly- metastasis are distinct entities at the clinical and molecular level.</p
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Consensus Statement: Expedition Inspiration Fund for Breast Cancer Research Meeting 2002
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44212/1/10549_2004_Article_5094133.pd
Recommended from our members
Expedition inspiration consensus 2001
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44209/1/10549_2004_Article_357949.pd
MicroRNA Expression Characterizes Oligometastasis(es)
Cancer staging and treatment presumes a division into localized or metastatic disease. We proposed an intermediate state defined by ≤ 5 cumulative metastasis(es), termed oligometastases. In contrast to widespread polymetastases, oligometastatic patients may benefit from metastasis-directed local treatments. However, many patients who initially present with oligometastases progress to polymetastases. Predictors of progression could improve patient selection for metastasis-directed therapy.Here, we identified patterns of microRNA expression of tumor samples from oligometastatic patients treated with high-dose radiotherapy.Patients who failed to develop polymetastases are characterized by unique prioritized features of a microRNA classifier that includes the microRNA-200 family. We created an oligometastatic-polymetastatic xenograft model in which the patient-derived microRNAs discriminated between the two metastatic outcomes. MicroRNA-200c enhancement in an oligometastatic cell line resulted in polymetastatic progression.These results demonstrate a biological basis for oligometastases and a potential for using microRNA expression to identify patients most likely to remain oligometastatic after metastasis-directed treatment
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Expedition Inspiration Fund for Breast Cancer Research Meeting 2003
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44216/1/10549_2004_Article_5139058.pd
In Support of a Patient-Driven Initiative and Petition to Lower the High Price of Cancer Drugs
Comment in
Lowering the High Cost of Cancer Drugs--III. [Mayo Clin Proc. 2016]
Lowering the High Cost of Cancer Drugs--I. [Mayo Clin Proc. 2016]
Lowering the High Cost of Cancer Drugs--IV. [Mayo Clin Proc. 2016]
In Reply--Lowering the High Cost of Cancer Drugs. [Mayo Clin Proc. 2016]
US oncologists call for government regulation to curb drug price rises. [BMJ. 2015
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