18 research outputs found
International Coercion, Emulation and Policy Diffusion: Market-Oriented Infrastructure Reforms, 1977-1999
Why do some countries adopt market-oriented reforms such as deregulation, privatization and liberalization of competition in their infrastructure industries while others do not? Why did the pace of adoption accelerate in the 1990s? Building on neo-institutional theory in sociology, we argue that the domestic adoption of market-oriented reforms is strongly influenced by international pressures of coercion and emulation. We find robust support for these arguments with an event-history analysis of the determinants of reform in the telecommunications and electricity sectors of as many as 205 countries and territories between 1977 and 1999. Our results also suggest that the coercive effect of multilateral lending from the IMF, the World Bank or Regional Development Banks is increasing over time, a finding that is consistent with anecdotal evidence that multilateral organizations have broadened the scope of the “conditionality” terms specifying market-oriented reforms imposed on borrowing countries. We discuss the possibility that, by pressuring countries into policy reform, cross-national coercion and emulation may not produce ideal outcomes.http://deepblue.lib.umich.edu/bitstream/2027.42/40099/3/wp713.pd
Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches
Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly
31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two
Background
The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd.
Methods
We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background.
Results
First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001).
Conclusions
In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
Rapid Voltammetric Measurements at Conducting Polymer Microelectrodes Using Ultralow-Capacitance Poly(3,4-ethylenedioxythiophene):Tosylate
Microwave-Plasma Dry-Etch for Fabrication of Conducting Polymer Microelectrodes
An inexpensive dry etch technology
based on a low-pressure microwave
plasma generated in a countertop microwave oven is characterized for
the patterning of a conductive polymer microelectrode. The etch process
is described, and the microwave-generated plasma is characterized
by emission spectroscopy. The plasma is generated with an atmospheric
mixture of mostly nitrogen and oxygen. A 10 μm wide band microelectrode
composed of PEDOT:Tosylate, an optically transparent conductive polymer,
is fabricated on a plastic substrate. Conductive polymer etch rates
are approximately 280–300 nm/minute. A patterned microelectrode
is characterized by atomic force microscopy. The horizontal distance
of a 10–90% height of a plasma-etched 150 nm thick electrode
was measured to be 360 ± 200 nm (<i>n</i> = 5). Electrodes
are further characterized using steady-state cyclic voltammetry, and
they have an electroactive area congruent with their geometric area.
Finally, a complete device is assembled and used as a separation platform
for biogenic amines. A microwave-etched 250 μm PEDOT:PSS electrode
is employed for end-channel electrochemical detection on this microchip,
where an electrophoretic separation of dopamine and catechol and a
micellar electrokinetic chromatography separation of dopamine and
serotonin are performed. Both mass and concentration LODs are comparable
to other electrochemical detectors in an end-channel configuration.
With the added advantages of easy processing, robustness, optical
transparency, and low cost, we expect microwave-etched polymer films
to be a viable alternative to traditional electrodes
Rapid Voltammetric Measurements at Conducting Polymer Microelectrodes Using Ultralow-Capacitance Poly(3,4-ethylenedioxythiophene):Tosylate
Rethinking Data Collection and Signal Processing. 2. Preserving the Temporal Fidelity of Electrochemical Measurements
Direct
electrochemical measurements of biological events are often
challenging because of the low signal relative to the magnitude of
the background and noise. When choosing a data processing approach,
the frequency and phase content of the data must be considered. Here,
we employ a zero-phase (infinite impulse response (IIR)) filter to
remove the noise from the analytical signal, while preserving the
phase content. In fast-scan cyclic voltammetry, the frequency content
of the signal is a function of the scan rate of the applied waveform.
Fourier analysis was used to develop a relationship between scan rate
and the filter cutoff frequency to maximize the reduction in noise,
while not altering the true nature of the analytical signal. The zero-phase
filter has the same effect as traditional filters with regards to
increasing the signal-to-noise ratio. Because the zero-phase filter
does not introduce a change to Δ<i>E</i><sub>peak</sub>, the heterogeneous electron rate transfer constant (0.10 cm/s) for
ferrocene is calculated accurately. The zero-phase filter also improves
electrochemical analysis of signaling molecules that have their oxidation
potential close to the switching potential. Lastly, a quantitative
approach to filtering amperometric traces of exocytosis based on the
rise time was developed