A pH-responsive crosslinker platform for antibody-drug conjugate (ADC) targeting delivery

We report a new 1-6 self-immolative, traceless crosslinker derived from the natural product gallic acid. The linker acts through a pH-dependent mechanism for drug release. This 5-(hydroxymethyl)pyrogallol orthoester derivative (HMPO) was stable for 24 hours at pH values of 7.4 and 6.6 and in plasma, releasing molecules bound to the hydroxymethyl moiety under acid-dependent stimuli at pH 5.5. The linker was non-toxic and was used for the conjugation of Doxorubicin (Doxo) or Combretastatin A4 with Cetuximab. The ADCs formed showed their pH responsivity reducing cell viability of A431 and A549 cancer cells better than Cetuximab alone. © 2022 The Royal Society of Chemistry

Detection of microparticles from human red blood cells by multiparametric flow cytometry

Background: During storage, red blood cells (RBC) undergo chemical and biochemical changes referred to as "storage lesions". These events determine the loss of RBC integrity, resulting in lysis and release of microparticles. There is growing evidence of the clinical importance of microparticles and their role in blood transfusion-related side effects and pathogen transmission. Flow cytometry is currently one of the most common techniques used to quantify and characterise microparticles. Here we propose multiparametric staining to monitor and quantify the dynamic release of microparticles by stored human RBC. Material and methods: RBC units (n=10) were stored under blood bank conditions for up to 42 days. Samples were tested at different time points to detect microparticles and determine the haemolysis rate (HR%). Microparticles were identified by flow cytometry combining carboxyfluorescein diacetate succinimidyl ester (CFSE) dye, annexin V and anti-glycophorin A antibody. Results: We demonstrated that CFSE can be successfully used to label closed vesicles with an intact membrane. The combination of CFSE and glycophorin A antibody was effective for monitoring and quantifying the dynamic release of microparticles from RBC during storage. Double staining with CFSE/glycophorin A was a more precise approach, increasing vesicle detection up to 4.7-fold vs the use of glycophorin A/annexin V alone. Moreover, at all the time points tested, we found a robust correlation (R=0.625; p=0.0001) between HR% and number of microparticles detected. Discussion: Multiparametric staining, based on a combination of CFSE, glycophorin A antibody and annexin V, was able to detect, characterise and monitor the release of microparticles from RBC units during storage, providing a sensitive approach to labelling and identifying microparticles for transfusion medicine and, more broadly, for cell-based therapies

The Impact of Crystal Light Yield Non-Proportionality on a Typical Calorimetric Space Experiment: Beam Test Measurements and Monte Carlo Simulations

Calorimetric space experiments were employed for the direct measurements of cosmic-ray spectra above the TeV region. According to several theoretical models and recent measurements, relevant features in both electron and nucleus fluxes are expected. Unfortunately, sizable disagreements among the current results of different space calorimeters exist. In order to improve the accuracy of future experiments, it is fundamental to understand the reasons of these discrepancies, especially since they are not compatible with the quoted experimental errors. A few articles of different collaborations suggest that a systematic error of a few percentage points related to the energy-scale calibration could explain these differences. In this work, we analyze the impact of the nonproportionality of the light yield of scintillating crystals on the energy scale of typical calorimeters. Space calorimeters are usually calibrated by employing minimal ionizing particles (MIPs), e.g., nonshowering proton or helium nuclei, which feature different ionization density distributions with respect to particles included in showers. By using the experimental data obtained by the CaloCube collaboration and a minimalist model of the light yield as a function of the ionization density, several scintillating crystals (BGO, CsI(Tl), LYSO, YAP, YAG and BaF2) are characterized. Then, the response of a few crystals is implemented inside the Monte Carlo simulation of a space calorimeter to check the energy deposited by electromagnetic and hadronic showers. The results of this work show that the energy scale obtained by MIP calibration could be affected by sizable systematic errors if the nonproportionality of scintillation light is not properly taken into account

Complex attosecond waveform synthesis at fel fermi

Free-electron lasers (FELs) can produce radiation in the short wavelength range extending from the extreme ultraviolet (XUV) to the X-rays with a few to a few tens of femtoseconds pulse duration. These facilities have enabled significant breakthroughs in the field of atomic, molecular, and optical physics, implementing different schemes based on two-color photoionization mechanisms. In this article, we present the generation of attosecond pulse trains (APTs) at the seeded FEL FERMI using the beating of multiple phase-locked harmonics. We demonstrate the complex attosecond waveform shaping of the generated APTs, exploiting the ability to manipulate independently the amplitudes and the phases of the harmonics. The described generalized attosecond waveform synthesis technique with an arbitrary number of phase-locked harmonics will allow the generation of sub-100 as pulses with programmable electric fields

A novel bioresponsive self-immolative spacer based on aza-quinone methide reactivity for the controlled release of thiols, phenols, amines, sulfonamides or amides

A stimuli-sensitive linker is one of the indispensable components of prodrugs for cancer therapy as it covalently binds the drug and releases it upon external stimulation at the tumour site. Quinone methide elimination has been widely used as the key transformation to release drugs based on their nucleofugacity. The usual approach is to bind the drug to the linker as a carbamate and release it as a free amine after a self-immolative 1,6-elimination. Although this approach is very efficient, it is limited to amines (as carbamates), alcohols or phenols (as carbonates) or other acidic functional groups. We report here a self-immolative spacer capable of directly linking and releasing amines, phenols, thiols, sulfonamides and carboxyamides after a reductive stimulus. The spacer is based on the structure of (5-nitro-2-pyrrolyl)methanol (NPYM-OH), which was used for the direct alkylation of the functional groups mentioned above. The spacer is metabolically stable and has three indispensable sites for bioconjugation: the bioresponsive trigger, the conjugated 1,6 self-immolative system and a third arm suitable for conjugation with a carrier or other modifiers. Release was achieved by selective reduction of the nitro group over Fe/Pd nanoparticles (NPs) in a micellar aqueous environment (H2O/TPGS-750-M), or by NADH mediated nitroreductase activation. A DFT study demonstrates that, during the 1,6 elimination, the transition state formed from 5-aminopyrrole has a lower activation energy compared to other 5-membered heterocycles or p-aminobenzyl derivatives. The NPYM scaffold was validated by late-stage functionalisation of approved drugs such as celecoxib, colchicine, vorinostat or ciprofloxacin. A hypoxia-activated NPYM-based prodrug (HAP) derived from HDAC inhibitor ST7612AA1 was also produced, which was active in cancer cells under hypoxic conditions

miR-424(322)/503 is a breast cancer tumor suppressor whose loss promotes resistance to chemotherapy

The female mammary gland is a very dynamic organ that undergoes continuous tissue remodeling during adulthood. Although it is well established that the number of menstrual cycles and pregnancy (in this case transiently) increase the risk of breast cancer, the reasons are unclear. Growing clinical and experimental evidence indicates that improper involution plays a role in the development of this malignancy. Recently, we described the miR-424(322)/503 cluster as an important regulator of mammary epithelial involution after pregnancy. Here, through the analysis of ∼3000 primary tumors, we show that miR-424(322)/503 is commonly lost in a subset of aggressive breast cancers and describe the genetic aberrations that inactivate its expression. Furthermore, through the use of a knockout mouse model, we demonstrate for the first time that loss of miR-424(322)/503 promotes breast tumorigenesis in vivo. Remarkably, we found that loss of miR-424(322)/503 promotes chemoresistance due to the up-regulation of two of its targets: BCL-2 and insulin-like growth factor-1 receptor (IGF1R). Importantly, targeted therapies blocking the aberrant activity of these targets restore sensitivity to chemotherapy. Overall, our studies reveal miR-424(322)/503 as a tumor suppressor in breast cancer and provide a link between mammary epithelial involution, tumorigenesis, and the phenomenon of chemoresistance

Guidewire replacement of valved tunneled-cuffed silicone catheters with power injectable polyurethane tunneled-cuffed catheters or with ports

Background: Silicone Cuffed Centrally Inserted Central venous catheters (CICCs) were a type of catheters that have been used for a long time especially in cancer patients. Recently, thanks to biomedic research progresses, polyurethane catheters have resulted in higher surgical performances compared to classical silicone ones. Indeed, the inferior calibers of these new catheters lead to an extremely faster infusion rate. The presence of a valve at the tip of the catheter could suggest an impossible replacement procedure over a Seldinger guidewire. Method: The aim of this article is to explain our replacement technique over guidewire of silicone cuffed and valved tunneled CICCs with a power injectable polyurethane cuffed tunneled CICC. The casistic presented was evaluated at the Vascular Access Unit of ASST Spedali Civili in Brescia, Italy. The study involved 35 successful catheter replacement over guidewire, meanwhile cases where patients presented sepsis, exit site infection, or catheter damage were premeditatedly excluded. Results:The maneuver was always conducted following the same procedure without noticing particular complications associated with CICC insertion. Indeed, the operation was quick, feasible, and safe. Septic, thromboembolic, or hemorrhagic complications also related to patients presenting dysfunctional coagulation cascade were not encountered. Conclusions: Our experience regarding the replacement technique of silicone cuffed and valved catheters over guidewire was considered feasible, accurate, and efficient for all patients treated, even in those presenting thrombocytopenia or a dysfunctional coagulation cascade

Guidewire replacement of tunneled central venous catheters in children reusing the same subcutaneous route

Background: Tunneled centrally inserted central venous catheters (CICCs) are a type of catheters used especially in cancer pediatric patients or affected from short bowel disease and malabsorption. Recently, thanks to biomedical research progresses, polyurethane catheters have resulted in high surgical performances with a low caliber but extremely fast infusion rate. Sometimes the replacement procedure over a Seldinger guidewire could be an appreciable technique especially reusing the same vein and the same tunnel of the previous catheter, with local anesthesia. The aim of this article was to explain our replacement technique over guidewire of tunneled CICCs on pediatric patients. Methods: The casuistry presented was evaluated at the Unit of Vascular Access of ASST Spedali Civili in Brescia, Italy. The study involved 7 successful catheter replacement over guidewire, meanwhile cases where patients presented sepsis, exit site infection or catheter damage were premeditatedly excluded. Three of them were tunneled and cuffed. Five catheters were in brachiocephalic vein and 2 in internal jugular vein. Results: Every procedure was ended without complications. Of seven patients, five of them underwent to the procedure only with local anesthesia and 2 patients require premedication with Midazolam. No one required general anesthesia. The maneuver was always conducted following the same procedure without noticing particular complications associated with CICC insertion. Indeed, the operation was quick, feasible and safe. Septic, thromboembolic, or hemorrhagic complications also related to patients presenting dysfunctional coagulation cascade were not encountered. Conclusions: Our experience regarding the replacement technique of tunneled catheters over guidewire was considered feasible, accurate and efficient for all patients treated, even in those presenting thrombocytopenia or dysfunctional coagulation cascade

How to remove a tunneled and cuffed central venous catheter quickly and safely? A little trick useful in children

Background: The aim of this study was to present our experience with a use of own variation of the traditional technique for tunneled and cuffed catheters removal. Methods: From July 2021 to March 2023, 110 tunneled cuffed centrally inserted central catheters (CICCs) were removed at the Vascular Access Unit of ASST Spedali Civili of Brescia using our particular technique; pediatric patients were 15 admitted to "Children Hospital" of Brescia. The catheter is cut with its adhesions above the cuff and then pulled out. The cuff is then removed with all adhesions attached. Results: Each procedure was successfully performed to the end with local anesthesia, also in younger children. The maneuver was very short and well tolerated. No related complications were observed. The maneuver has always been considered easy even by less experienced surgeons. The scars were aesthetically good and well accepted by the patients. Conclusions: The technique described has the advantage of not requiring the careful lysis of the adherence from the cuff. If the procedure is quick it can be performed without general anesthesia and without significant psychological trauma also in less compliant children. The skin cut very short leaves an almost invisible scar. It is another notable advantage especially for young girls

Taller De Liderazgo I-DE335-201701

Descripción: Resulta innegable que el mundo de hoy necesita líderes sin embargo esta visión de liderazgo podría resultar etérea para muchos profesionales. Este curso te permite desarrollar una visión de liderazgo trabajada a partir de la propia experiencia entrenándote en fortalecer tus habilidades y conocer y aceptar tus debilidades.Propósito: Curso general de la carrera de Derecho de carácter teórico ¿ práctico que al ser del primer ciclo no cuenta con prerrequisitos y está dirigido a los estudiantes del primer ciclo que busca desarrollar la competencia general de pensamiento innovador nivel 1 sobre la base que el alumno conoce sus necesidades y se plantea mejoras. El alumno debe conocerse para plantearse su proyecto de vida a corto mediano y largo plazo