528 research outputs found
PRICE DISCRIMINATIONS AND THEIR JUSTIFICATIONS UNDER THE ROBINSON-PATMAN ACT OF 1936
The Robinson-Patman Act was approved by the President on June 19, 1936. The purpose of the act was to amend section 2 of the Clayton Act, which prohibited price discriminations in interstate commerce. Congress, by amending section 2 of the Clayton Act, broadened the scope of the section by extending its purposes and prohibitions to price discriminations not formerly covered and by prohibiting other forms of discrimination which give favored purchasers undue cost advantages over their non-favored competitors. It also reduced the extent of requisite competitive injury
Demystifying Beer... Do You Want Fries With That?
This paper concerns the strongly theory based organisational intervention - Stafford Beers' Viable Systems Diagnosis (VSD). The assumption that organisations have difficulty in transforming good theories into effective workplace practices is examined using VSD. We propose levels of knowledge or recursions of the Beer system that are appropriate and effective in terms of organisational interventions. We contend that the lexis emanating from Brain of the Firm, and The Heart of the Enterprise exacerbates the complexity of VSD causing readers to focus on Diagnosing the System. We suggest this outcome contributes to the non-popularity of VSD, but that Beer himself cannot be exonerated. The lack of fundamental VSD principles, identified as a deficiency in Diagnosing the System is expanded from the antecedents, Brain and Heart. The paper concludes by considering a systematic categorisation of Beer's work that will guide organizational change agents wishing to use this intellectually complex and powerful system
Increased gastrin-releasing peptide (GRP) receptor expression in tumour cells confers sensitivity to [Arg6,D-Trp7,9,NmePhe8]-substance P (6-11)-induced growth inhibition.
[Arg(6),D-Trp(7,9),N(me)Phe(8)]-substance P (6-11) (SP-G) is a novel anticancer agent that has recently completed phase I clinical trials. SP-G inhibits mitogenic neuropeptide signal transduction and small cell lung cancer (SCLC) cell growth in vitro and in vivo. Using the SCLC cell line series GLC14, 16 and 19, derived from a single patient during the clinical course of their disease and the development of chemoresistance, it is shown that there was an increase in responsiveness to neuropeptides. This was paralleled by an increased sensitivity to SP-G. In a selected panel of tumour cell lines (SCLC, non-SCLC, ovarian, colorectal and pancreatic), the expression of the mitogenic neuropeptide receptors for vasopressin, gastrin-releasing peptide (GRP), bradykinin and gastrin was examined, and their sensitivity to SP-G tested in vitro and in vivo. The tumour cell lines displayed a range of sensitivity to SP-G (IC(50) values from 10.5 to 119 microM). The expression of the GRP receptor measured by reverse transcriptase-polymerase chain reaction, correlated significantly with growth inhibition by SP-G. Moreover, introduction of the GRP receptor into rat-1A fibroblasts markedly increased their sensitivity to SP-G. The measurement of receptor expression from biopsy samples by polymerase chain reaction could provide a suitable diagnostic test to predict efficacy to SP-G clinically. This strategy would be of potential benefit in neuropeptide receptor-expressing tumours in addition to SCLC, and in tumours that are relatively resistant to conventional chemotherapy
Flavones induce neutrophil apoptosis by down-regulation of Mcl-1 via a proteasomal-dependent pathway
Neutrophil apoptosis and subsequent nonphlogistic clearance by surrounding phagocytes are key to the successful resolution of neutrophilic inflammation, with dysregulated apoptosis reported in multiple human inflammatory diseases. Enhancing neutrophil apoptosis has proresolution and anti-inflammatory effects in preclinical models of inflammation. Here we investigate the ability of the flavones apigenin, luteolin, and wogonin to induce neutrophil apoptosis in vitro and resolve neutrophilic inflammation in vivo. Human neutrophil apoptosis was assessed morphologically and by flow cytometry following incubation with apigenin, luteolin, and wogonin. All three flavones induced time- and concentration-dependent neutrophil apoptosis (apigenin, EC(50)=12.2 μM; luteolin, EC(50)=14.6 μM; and wogonin, EC(50)=28.9 μM). Induction of apoptosis was caspase dependent, as it was blocked by the broad-spectrum caspase inhibitor Q-VD-OPh and was associated with both caspase-3 and caspase-9 activation. Flavone-induced apoptosis was preceded by down-regulation of the prosurvival protein Mcl-1, with proteasomal inhibition preventing flavone-induced Mcl-1 down-regulation and apoptosis. The flavones abrogated the survival effects of mediators that prolong neutrophil life span, including lipoteichoic acid, peptidoglycan, dexamethasone, and granulocyte-macrophage colony stimulating factor, by driving apoptosis. Furthermore, wogonin enhanced resolution of established neutrophilic inflammation in a zebrafish model of sterile tissue injury. Wogonin-induced resolution was dependent on apoptosis in vivo as it was blocked by caspase inhibition. Our data show that the flavones induce neutrophil apoptosis and have potential as neutrophil apoptosis-inducing anti-inflammatory, proresolution agents.—Lucas, C. D., Allen, K. C., Dorward, D. A., Hoodless, L. J., Melrose, L. A., Marwick, J. A., Tucker, C. S., Haslett, C., Duffin, R., Rossi, A. G. Flavones induce neutrophil apoptosis by down-regulation of Mcl-1 via a proteasomal-dependent pathway
Transcriptome-scale similarities between mouse and human skeletal muscles with normal and myopathic phenotypes
BACKGROUND: Mouse and human skeletal muscle transcriptome profiles vary by muscle type, raising the question of which mouse muscle groups have the greatest molecular similarities to human skeletal muscle. METHODS: Orthologous (whole, sub-) transcriptome profiles were compared among four mouse-human transcriptome datasets: (M) six muscle groups obtained from three mouse strains (wildtype, mdx, mdx(5cv)); (H1) biopsied human quadriceps from controls and Duchenne muscular dystrophy patients; (H2) four different control human muscle types obtained at autopsy; and (H3) 12 different control human tissues (ten non-muscle). RESULTS: Of the six mouse muscles examined, mouse soleus bore the greatest molecular similarities to human skeletal muscles, independent of the latters' anatomic location/muscle type, disease state, age and sampling method (autopsy versus biopsy). Significant similarity to any one mouse muscle group was not observed for non-muscle human tissues (dataset H3), indicating this finding to be muscle specific. CONCLUSION: This observation may be partly explained by the higher type I fiber content of soleus relative to the other mouse muscles sampled
Highly controlled, reproducible measurements of aerosol emissions from combustion of a common African biofuel source
Particulate emissions from biomass burning can both alter the atmosphere's radiative
balance and cause significant harm to human health. However, due to the large
effect on emissions caused by even small alterations to the way in which
a fuel burns, it is difficult to study particulate production of biomass
combustion mechanistically and in a repeatable manner. In order to address
this gap, in this study, small wood samples sourced from Côte D'Ivoire in
West Africa were burned in a highly controlled laboratory environment. The
shape and mass of samples, available airflow and surrounding thermal
environment were carefully regulated. Organic aerosol and refractory black
carbon emissions were measured in real time using an Aerosol Mass
Spectrometer and a Single Particle Soot Photometer, respectively. This
methodology produced remarkably repeatable results, allowing aerosol
emissions to be mapped directly onto different phases of combustion.
Emissions from pyrolysis were visible as a distinct phase before flaming was
established. After flaming combustion was initiated, a black-carbon-dominant
flame was observed during which very little organic aerosol was produced,
followed by a period that was dominated by organic-carbon-producing
smouldering combustion, despite the presence of residual flaming. During
pyrolysis and smouldering, the two phases producing organic aerosol, distinct
mass spectral signatures that correspond to previously reported variations in
biofuel emissions measured in the atmosphere are found. Organic aerosol
emission factors averaged over an entire combustion event were found to be
representative of the time spent in the pyrolysis and smouldering phases,
rather than reflecting a coupling between emissions and the mass loss of the
sample. Further exploration of aerosol yields from similarly carefully
controlled fires and a careful comparison with data from macroscopic fires
and real-world emissions will help to deliver greater constraints on the
variability of particulate emissions in atmospheric systems
Downregulation of Mcl-1 has anti-inflammatory pro-resolution effects and enhances bacterial clearance from the lung
Phagocytes not only coordinate acute inflammation and host defense at mucosal sites, but also contribute to tissue damage. Respiratory infection causes a globally significant disease burden and frequently progresses to acute respiratory distress syndrome, a devastating inflammatory condition characterized by neutrophil recruitment and accumulation of protein-rich edema fluid causing impaired lung function. We hypothesized that targeting the intracellular protein myeloid cell leukemia 1 (Mcl-1) by a cyclin-dependent kinase inhibitor (AT7519) or a flavone (wogonin) would accelerate neutrophil apoptosis and resolution of established inflammation, but without detriment to bacterial clearance. Mcl-1 loss induced human neutrophil apoptosis, but did not induce macrophage apoptosis nor impair phagocytosis of apoptotic neutrophils. Neutrophil-dominant inflammation was modelled in mice by either endotoxin or bacteria (Escherichia coli). Downregulating inflammatory cell Mcl-1 had anti-inflammatory, pro-resolution effects, shortening the resolution interval (R(i)) from 19 to 7 h and improved organ dysfunction with enhanced alveolar–capillary barrier integrity. Conversely, attenuating drug-induced Mcl-1 downregulation inhibited neutrophil apoptosis and delayed resolution of endotoxin-mediated lung inflammation. Importantly, manipulating lung inflammatory cell Mcl-1 also accelerated resolution of bacterial infection (R(i); 50 to 16 h) concurrent with enhanced bacterial clearance. Therefore, manipulating inflammatory cell Mcl-1 accelerates inflammation resolution without detriment to host defense against bacteria, and represents a target for treating infection-associated inflammation
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