95 research outputs found
CHOLANE AND LANOSTANE DERIVATIVES: ANTIMICROBIAL EVALUATION
Steroids are natural compounds with several important applications in many fields of research, such as
medicinal chemistry, pharmacology, supramolecular chemistry and nanotechnology.In particular, bile
acids such as lithocholic acid (LCA) and ursodeoxycholic acid (UDCA) have been considered quite useful as
starting points for a rich and different set of medicinal chemistry activities.
Besides, the discovery of bioactive ingredients from plants and fungi is always the main target in medicinal
chemistry. The lanostane-type triterpenoid 3b-hydroxylanosta-8,24-diene-21-oic acid (Trametenolic acid,
TMA) was the main bioactive component of Gloeophyllum odoratum, which was reported to possess widely
bioactivities, including tumor cell anti-proliferation effects (for example, human HL-60 leukemia, human KB
epidermoid carcinoma, murine L1210 leukemia cells, Caski, HT-3, T-24, etc.), inhibition of enzyme activity
(human thrombin, bovine trypsin and so on).Nevertheless, trametenolic acid was scarcely investigated as
antimicrobial agent.
Structurally, bile acids (LCA and UDCA) and trametenolic acid are similar since they may be regarded as
consisting of two components, a rigid steroid nucleus and an aliphatic side chain possessing a carboxyl
group. On the basis of these considerations, six new compounds bearing a guanidine moiety in their side
chain were synthesized using LCA, UDCA and TMA as starting materials. The parent bile acids,
TMA and their resulting derivatives were evaluated for antimicrobial activity against S. aureus, B. subtilis
and M. smegmatis. The derivative 3a-hydroxy-23-guanidino-5b-cholane showed the best activity, with MIC
values of 12.5 \u3bcM against S. aureus, 5 \u3bcM against B. subtilis and 50 \u3bcM against M. smegmatis. The cytotoxic
activity of bile acids, trametenolic acid and derivatives was also evaluated against HT-29 cell lin
Robust Online Hamiltonian Learning
In this work we combine two distinct machine learning methodologies,
sequential Monte Carlo and Bayesian experimental design, and apply them to the
problem of inferring the dynamical parameters of a quantum system. We design
the algorithm with practicality in mind by including parameters that control
trade-offs between the requirements on computational and experimental
resources. The algorithm can be implemented online (during experimental data
collection), avoiding the need for storage and post-processing. Most
importantly, our algorithm is capable of learning Hamiltonian parameters even
when the parameters change from experiment-to-experiment, and also when
additional noise processes are present and unknown. The algorithm also
numerically estimates the Cramer-Rao lower bound, certifying its own
performance.Comment: 24 pages, 12 figures; to appear in New Journal of Physic
UV-Casting on methacrylated PCL for the production of a peripheral nerve implant containing an array of porous aligned microchannels
Peripheral nerves are basic communication structures guiding motor and sensory information from the central nervous system to receptor units. Severed peripheral nerve injuries represent a large clinical problem with relevant challenges to successful synthetic nerve repair scaffolds as substitutes to autologous nerve grafting. Numerous studies reported the use of hollow tubes made of synthetic polymers sutured between severed nerve stumps to promote nerve regeneration while providing protection for external factors, such as scar tissue formation and inflammation. Few approaches have described the potential use of a lumen structure comprised of microchannels or microfibers to provide axon growth avoiding misdirection and fostering proper healing. Here, we report the use of a 3D porous microchannel-based structure made of a photocurable methacrylated polycaprolactone, whose mechanical properties are comparable to native nerves. The neuro-regenerative properties of the polymer were assessed in vitro, prior to the implantation of the 3D porous structure, in a 6-mm rat sciatic nerve gap injury. The manufactured implants were biocompatible and able to be resorbed by the host’s body at a suitable rate, allowing the complete healing of the nerve. The innovative design of the highly porous structure with the axon guiding microchannels, along with the observation of myelinated axons and Schwann cells in the in vivo tests, led to a significant progress towards the standardized use of synthetic 3D multichannel-based structures in peripheral nerve surgery
Software systems for operation, control, and monitoring of the EBEX instrument
We present the hardware and software systems implementing autonomous
operation, distributed real-time monitoring, and control for the EBEX
instrument. EBEX is a NASA-funded balloon-borne microwave polarimeter designed
for a 14 day Antarctic flight that circumnavigates the pole. To meet its
science goals the EBEX instrument autonomously executes several tasks in
parallel: it collects attitude data and maintains pointing control in order to
adhere to an observing schedule; tunes and operates up to 1920 TES bolometers
and 120 SQUID amplifiers controlled by as many as 30 embedded computers;
coordinates and dispatches jobs across an onboard computer network to manage
this detector readout system; logs over 3~GiB/hour of science and housekeeping
data to an onboard disk storage array; responds to a variety of commands and
exogenous events; and downlinks multiple heterogeneous data streams
representing a selected subset of the total logged data. Most of the systems
implementing these functions have been tested during a recent engineering
flight of the payload, and have proven to meet the target requirements. The
EBEX ground segment couples uplink and downlink hardware to a client-server
software stack, enabling real-time monitoring and command responsibility to be
distributed across the public internet or other standard computer networks.
Using the emerging dirfile standard as a uniform intermediate data format, a
variety of front end programs provide access to different components and views
of the downlinked data products. This distributed architecture was demonstrated
operating across multiple widely dispersed sites prior to and during the EBEX
engineering flight.Comment: 11 pages, to appear in Proceedings of SPIE Astronomical Telescopes
and Instrumentation 2010; adjusted metadata for arXiv submissio
Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications
BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients.
OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs.
DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification.
PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries.
MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes.
RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (VT) size was 500 ml, or 7 to 9 ml kg1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P < 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P < 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure.
CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high VT and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome
Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications: LAS VEGAS - An observational study in 29 countries
BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (V T) size was 500 ml, or 7 to 9 ml kg−1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P ˂ 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P ˂ 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high V T and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome.</p
2023 MASCC and ESMO guideline update for the prevention of chemotherapy- and radiotherapy-induced nausea and vomiting
Nausea and vomiting are still considered to be two of the most troublesome adverse events (AEs) for patients treated with antineoplastic therapy. To optimise the utility of available antiemetic prophylaxis, updated reviews of the relevant literature and evidence-based guideline recommendations are crucial.
The European Society for Medical Oncology (ESMO) and the Multinational Association of Supportive Care in Cancer (MASCC) completed the fourth Consensus Conference on Antiemetics for the prevention of nausea and vomiting in patients with cancer in Copenhagen in June 2015. This article is an update of the 2015 guidelines.Meeting and production costs have been covered by MASCC and ESMO from central funds.https://www.esmoopen.comhj2024ImmunologySDG-03:Good heatlh and well-bein
First implementation of TES bolometer arrays with SQUID-based multiplexed readout on a balloon-borne platform
EBEX (the E and B EXperiment) is a balloon-borne telescope designed to measure the polarisation of the cosmic microwave background radiation. During a two week long duration science flight over Antarctica, EBEX will operate 768, 384 and 280 spider-web transition edge sensor (TES) bolometers at 150, 250 and 410 GHz, respectively. The 10-hour EBEX engineering flight in June 2009 over New Mexico and Arizona provided the first usage of both a large array of TES bolometers and a Superconducting QUantum Interference Device (SQUID) based multiplexed readout in a space-like environment. This successful demonstration increases the technology readiness level of these bolometers and the associated readout system for future space missions. A total of 82, 49 and 82 TES detectors were operated during the engineering flight at 150, 250 and 410 GHz. The sensors were read out with a new SQUID-based digital frequency domain multiplexed readout system that was designed to meet the low power consumption and robust autonomous operation requirements presented by a balloon experiment. Here we describe the system and the remote, automated tuning of the bolometers and SQUIDs. We compare results from tuning at float to ground, and discuss bolometer performance during fligh
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