Persistence in the Methadone Maintenance Program and Its Relationship with the Medication Regimen Complexity Index in Opioid-Dependent Patients.

It has been shown that the Medication Regimen Complexity Index (MRCI) is a useful and reliable tool for calculating the complexity of the pharmacotherapeutic regimen (CPR). Furthermore, a high MRCI is associated with lower adherence. However, the MRCI of opioid-dependent patients (ODP) has not been studied. The aim of this study is to calculate the Methadone Maintenance Program (MMP) persistence and the MRCI score in a ODP cohort. Second, to analyze its relationship and association with other variables. To accomplish this research, an observational study including adults with a confirmed diagnosis of opiate-dependency according to the DSM-5 in a MMP center was carried out. To define MMP-persistence, a group was created by the researchers who defined five weighted items according to their agreed importance. Our first contribution was to create a new definition of MMP-persistence. This study also identified age, comorbidities, and received methadone maintenance doses as successful predictors for MMP-persistence. We have also shown that the MRCI does not seem to be a useful tool to determine MMP-persistence, probably because there are multiple factors that influence it in addition to the CPR. It is necessary to continue searching for more precise selection and stratification tools for ODP to improve their persistence.

Physicochemical stability of bortezomib solutions for subcutaneous administration.

For the majority of cytotoxic drug preparations, such as bortezomib, the unit dose information is not available. In addition, there is a lack of information on the physicochemical stability of the pharmaceutical preparation after opening; this information is crucial for its administration to patients in successive visits, and the per-patient cost can be affected. The purpose of our proposed physicochemical stability study is to determine the shelf life of the reconstituted liquid product under refrigeration and clinical practice conditions. This evaluation was extended to both vials and ready-to-use syringes prefilled with the contents of the open vial. The stability test design includes the specified storage conditions and the critical physicochemical parameters of reconstituted injectable bortezomib. Furthermore, this approach includes the determination of impurities, the monitoring of the purity of the mean peak using a photodiode array, the control of the mass balance, the monitoring of subvisible particles using a laser diffraction analyser, and the setting of stability specifications. For the chemical stability study, the amount of bortezomib and its degradation products were determined using a stability-indicating HPLC method. The physical inspection of the samples was performed throughout the stability study, and their pH values were also monitored. Bortezomib (2.5 mg/mL) in 0.9% sodium chloride remained stable for 7 days when stored in both polypropylene syringes and vials at 5 ± 3 °C (refrigeration) and shielded from light. Additionally, it exhibits stability for 24 h under storage conditions simulating clinical use (20-30 °C and protected from light). The proposed protocol provides the stability in the vials once reconstituted and in prefilled refrigerated syringes; this protocol can be used to reduce waste and increase cost savings.

Design of mobile and website health application devices for drug tolerability in hereditary fructose intolerance.

BACKGROUND: Hereditary fructose intolerance (HFI) is a rare metabolic disease caused by aldolase B deficiency. The aim of our study was to analyse excipient tolerability in patients with HFI and other related diseases and to design mobile and website health applications to facilitate the search for drugs according to their tolerance. RESULTS: A total of 555 excipients listed in the Spanish Medicines Agency database (July 2023) were classified as suitable for HFI patients, suitable with considerations ((glucose and glucose syrup, intravenous sucrose, oral mannitol, polydextrose, gums and carrageenans, ethanol, sulfite caramel and vanilla), not recommended (intravenous mannitol) and contraindicated (fructose, oral sucrose, invert sugar, sorbitol, maltitol, lactitol, isomaltitol, fruit syrups, honey, sucrose esters and sorbitol esters). Glucose and glucose syrup were classified as suitable with considerations due to its possible fructose content and their potential endogenous fructose production. For other related intolerances, wheat starch was contraindicated and oatmeal was not recommended in celiac disease; oral lactose and lactose-based coprocessed excipient (Cellactose®) were not recommended in lactose intolerance; and glucose, invert sugar and oral sucrose were not recommended in diabetes mellitus. The applications were named IntoMed®. Results are listed in order of tolerability (suitable drugs appear first and contraindicated drugs at the end), and they are accompanied by a note detailing their classified excipients. If a drug contains excipients within different categories, the overall classification will be the most restrictive. The apps are also able to classify substances with the same criteria if they act as active ingredients. The tools exhibited good usability (82.07 ± 13.46 points on the System Usability Scale [range: 0-100]) on a sample of HFI patients, their families and health care professionals. CONCLUSIONS: IntoMed® is a tool for finding information about the tolerability of drugs according to excipients for patients with HFI and other related intolerances, with good usability. It is a fast and reliable system that covers the current excipient legislation and expands on it with other specific information: HFI patients should be alert for excipients such as mannitol (especially in intravenous drugs), fruit syrups, honey, sulfite caramel or vanilla. Glucose might contain or produce fructose, and special precaution is needed because of potential errors in their composition.

Solubilizer Tag Effect on PD-L1/Inhibitor Binding Properties for m-Terphenyl Derivatives.

Although heavily studied, the subject of anti-PD-L1 small-molecule inhibitors is still elusive. Here we present a systematic overview of the principles behind successful anti-PD-L1 small-molecule inhibitor design on the example of the m-terphenyl scaffold, with a particular focus on the neglected influence of the solubilizer tag on the overall affinity toward PD-L1. The inhibitor developed according to the proposed guidelines was characterized through its potency in blocking PD-1/PD-L1 complex formation in homogeneous time-resolved fluorescence and cell-based assays. The affinity is also explained based on the crystal structure of the inhibitor itself and its costructure with PD-L1 as well as a molecular modeling study. Our results structuralize the knowledge related to the strong pharmacophore feature of the m-terphenyl scaffold preferential geometry and the more complex role of the solubilizer tag in PD-L1 homodimer stabilization.

Structural and biological characterization of pAC65, a macrocyclic peptide that blocks PD-L1 with equivalent potency to the FDA-approved antibodies.

Recent advances in immuno-oncology have opened up new and impressive treatment options for cancer. Notwithstanding, overcoming the limitations of the current FDA-approved therapies with monoclonal antibodies (mAbs) that block the PD-1/PD-L1 pathway continues to lead to the testing of multiple approaches and optimizations. Recently, a series of macrocyclic peptides have been developed that exhibit binding strengths to PD-L1 ranging from sub-micromolar to micromolar. In this study, we present the most potent non-antibody-based PD-1/PD-L1 interaction inhibitor reported to date. The structural and biological characterization of this macrocyclic PD-L1 targeting peptide provides the rationale for inhibition of both PD-1/PD-L1 and CD80/PD-L1 complexes. The IC50 and EC50 values obtained in PD-L1 binding assays indicate that the pAC65 peptide has potency equivalent to the current FDA-approved mAbs and may have similar activity to the BMS986189 peptide, which entered the clinical trial and has favorable safety and pharmacokinetic data. The data presented here delineate the generation of similar peptides with improved biological activities and applications not only in the field of cancer immunotherapy but also in other disorders related to the immune system.

Toxic metals from atmospheric particulate matter in food species of tomato (Solanum lycopersicum) and strawberry (Fragaria x ananassa) used in urban gardening. A closed chamber study.

In this work, two plant foods, strawberry and tomato, were subjected to exposure to metals from synthetic airborne particles in a closed chamber experiment. The synthetic particles were obtained in the laboratory. Within the closed chamber, particles were added and recirculated for 4 days in a turbulent air stream, causing deposition on the different parts of the plants. They were evaluated because of their increasingly frequent cultivation in urban gardens of cities. The main objectives were to determine whether the species accumulate metals significantly, which species accumulate the most, and in which parts of the plant. Finally, an attempt was made to differentiate the accumulation of pollutants by surface deposition on leaves and fruits from the adsorbed metals into the leaf or the fruit by their stomata or cuticles. The concentration of heavy metals was quantified in fruits, leaves and the soil after exposure. Metals were evaluated as a whole and individually, both in dry and fresh weight basis. The decrease of particulate matter and metals in the air inside the chamber was also studied in order to evaluate the use of both food species as air purifier by vertical gardens. The concentration of metals in plants (mg kg-1) and airborne particles (mg m-3) was measured by microwave plasma optical emission spectroscopy (MP-AES). For the sake comparison of total amount of metals in the samples concentrations were normalized. Strawberries was the food species that accumulated the largest amount of metals. In a dry weight basis, tomato leaves and strawberry fruits were the parts of the plants with higher accumulation capacity of particles and metals. The potential toxic elements Cd, Ni and Cr in tomato leaves and in strawberry fruits had a higher presence in the interior of the plant system. In a fresh weight basis, the strawberry fruit had the most accumulation capacity for metals.

Design, Synthesis, and Biological Evaluation of 2-Hydroxy-4-phenylthiophene-3-carbonitrile as PD-L1 Antagonist and Its Comparison to Available Small Molecular PD-L1 Inhibitors.

In search of a potent small molecular PD-L1 inhibitor, we designed and synthesized a compound based on a 2-hydroxy-4-phenylthiophene-3-carbonitrile moiety. Ligand's performance was tested in vitro and compared side-by-side with a known PD-L1 antagonist with a proven bioactivity BMS1166. Subsequently, we modified both compounds to allow 18F labeling that could be used for PET imaging. Radiolabeling, which is used in drug development and diagnosis, was applied to investigate the properties of those ligands and test them against tissue sections with diverse expression levels of PD-L1. We confirmed biological activity toward hPD-L1 for this inhibitor, comparable with BMS1166, while holding enhanced pharmacological properties.

Biocompatible Short-Peptides Fibrin Co-assembled Hydrogels.

Fibrin hydrogels made by self-assembly of fibrinogen obtained from human plasma have shown excellent biocompatible and biodegradable properties and are widely used in regenerative medicine. The fibrinogen self-assembly process can be triggered under physiological conditions by the action of thrombin, allowing the injection of pregel mixtures that have been used as cell carriers, wound-healing systems, and bio-adhesives. However, access to fibrinogen from human plasma is expensive and fibrin gels have limited mechanical properties, which make them unsuitable for certain applications. One solution to these problems is to obtain composite gels made of fibrin and other polymeric compounds that improve their mechanical properties and usage. Herein, we prepared composite hydrogels made by the self-assembly of fibrinogen together with Fmoc-FF (Fmoc-diphenylalanine) and Fmoc-RGD (Fmoc-arginine-glycine-aspartic acid). We have shown that the mixture of these three peptides co-assembles and gives rise to a unique type of supramolecular fiber, whose morphology and mechanical properties can be modulated. We have carried out a complete characterization of these materials from chemical, physical, and biological points of view. Composite gels have improved mechanical properties compared to pure fibrin gels, as well as showing excellent biocompatibility ex vivo. In vivo experiments have shown that these gels do not cause any type of inflammatory response or tissue damage and are completely resorbed in short time, which would enable their use as vehicles for cell, drug, or growth factor release.

Resultados de la cirugía conservadora y radical de la mama en pacientes operadas en el Centro de Investigaciones Médico Quirúrgicas, Cuba / Results of Conservative or Radical Breast Surgeries in Patients Operated on at Centro de Investigaciones Médico Quirúrgicas, Cuba

Introducción: El cáncer ha causado más muertes que todas las guerras y catástrofes conocidas. En particular, el cáncer de mama se ha convertido en una pandemia que amenaza con seguir propagándose. Objetivo: Describir las diferencias en cuanto a los resultados obtenidos de la cirugía conservadora y radical como tratamiento del cáncer de mama. Métodos: Se realizó un estudio analítico, observacional, descriptivo y retrospectivo en un universo de 177 pacientes con diagnóstico de cáncer de mama en el servicio de Cirugía General del Centro de Investigaciones Médico Quirúrgicas de La Habana, Cuba. Todas recibieron tratamiento quirúrgico en el período comprendido de enero de 2011 a diciembre de 2016. Resultados: De las pacientes estudiadas, el 92,09 por ciento no presentaron antecedentes de patología mamaria, mientras que el 36,72 por ciento tuvieron como antecedente patológico familiar cáncer de mama. Predominaron las pacientes mayores de 70 años en ambas técnicas quirúrgicas. En el grupo de 30-40 años solamente se practicaron técnicas conservadoras. Con respecto al estadiamiento, predominó la etapa II de la enfermedad. La sobrevida global a los 5 años fue superior al 90 por ciento, mientras que el intervalo libre de enfermedad se mantuvo en valores similares para ambas técnicas. Conclusiones: Se realizaron mayor número de cirugías conservadoras de mama en pacientes que se encontraban en etapas clínicas más tempranas de la enfermedad y la sobrevida global de los procedimientos conservadores fue ligeramente mayor(AU)

Introduction: Cancer has caused more deaths than all known wars and catastrophes. Particularly speaking, breast cancer has become a pandemic that threatens to continue to spread. Objective: To describe the differences based on the results obtained from conservative and radical surgery as a treatment for breast cancer. Methods: An analytical, observational, descriptive and retrospective study was carried out with a universe of 177 female patients diagnosed with breast cancer in the general surgery service of Centro de Investigaciones Médico Quirúrgicas, of La Habana, Cuba. All of them received surgical treatment in the period from January 2011 to December 2016. Results: 92.09 percent of the patients studied had no history of breast pathology, while 36.72 percent had breast cancer as a family pathological history. Patients over 70 years of age predominated in both surgical techniques. In the group of 30-40 years of age only conservative techniques were performed. With respect to staging, there was a predominance of the disease in stage II. Overall survival at 5 years was higher than 90 percent, while the disease-free interval remained at similar values for both techniques. Conclusions: A greater amount of breast-conserving surgeries were performed in patients at earlier clinical stages of the disease, while overall survival of conservative procedures was slightly higher(AU)

Modeling Adsorption of CO2 in Rutile Metallic Oxide Surfaces: Implications in CO2 Catalysis.

CO2 is the most abundant greenhouse gas, and for this reason, it is the main target for finding solutions to climatic change. A strategy of environmental remediation is the transformation of CO2 to an aggregated value product to generate a carbon-neutral cycle. CO2 reduction is a great challenge because of the large C=O dissociation energy, ~179 kcal/mol. Heterogeneous photocatalysis is a strategy to address this issue, where the adsorption process is the fundamental step. The focus of this work is the role of adsorption in CO2 reduction by means of modeling the CO2 adsorption in rutile metallic oxides (TiO2, GeO2, SnO2, IrO2 and PbO2) using Density Functional Theory (DFT) and periodic DFT methods. The comparison of adsorption on different metal oxides forming the same type of crystal structure allowed us to observe the influence of the metal in the adsorption process. In the same way, we performed a comparison of the adsorption capability between two different surface planes, (001) and (110). Two CO2 configurations were observed, linear and folded: the folded conformations were observed in TiO2, GeO2 and SnO2, while the linear conformations were present in IrO2 and PbO2. The largest adsorption efficiency was displayed by the (001) surface planes. The CO2 linear and folded configurations were related to the interaction of the oxygen on the metallic surface with the adsorbate carbon, and the linear conformations were associated with the physisorption and folded configurations with chemisorption. TiO2 was the material with the best performance for CO2 interactions during the adsorption.

Identification of histological threshold concepts in health sciences curricula: Students' perception.

Students' metacognitive skills and perceptions are considered important variables for high-quality learning. In this study, students' perceptions were used to identify histological threshold concepts (integrative, irreversible, transformative, and troublesome) in three health sciences curricula. A specific questionnaire was developed and validated to characterize students' perceptions of histological threshold concepts. A sample of 410 undergraduate students enrolled in the dentistry, medicine, and pharmacy degree programs participated in the study. Concepts assessed in the study were clustered to ten categories (factors) by exploratory and confirmatory factor analysis. Concepts linked to tissue organization and tissue functional states received the highest scores from students in all degree programs, suggesting that the process of learning histology requires the integration of both static concepts related to the constituent elements of tissues and dynamic concepts such as stem cells as a tissue renewal substrate, or the euplasic, proplasic and retroplasic states of tissues. The complexity of integrating static and dynamic concepts may pose a challenging barrier to the comprehension of histology. In addition, several differences were detected among the students in different degree programs. Dentistry students more often perceived morphostructural concepts as threshold concepts, whereas medical students highlighted concepts related to two-dimensional microscopic identification. Lastly, pharmacy students identified concepts related to tissue general activity as critical for the comprehension and learning of histology. The identification of threshold concepts through students' perceptions is potentially useful to improve the teaching and learning process in health sciences curricula.

Computer- and NMR-Aided Design of Small-Molecule Inhibitors of the Hub1 Protein.

By binding to the spliceosomal protein Snu66, the human ubiquitin-like protein Hub1 is a modulator of the spliceosome performance and facilitates alternative splicing. Small molecules that bind to Hub1 would be of interest to study the protein-protein interaction of Hub1/Snu66, which is linked to several human pathologies, such as hypercholesterolemia, premature aging, neurodegenerative diseases, and cancer. To identify small molecule ligands for Hub1, we used the interface analysis, peptide modeling of the Hub1/Snu66 interaction and the fragment-based NMR screening. Fragment-based NMR screening has not proven sufficient to unambiguously search for fragments that bind to the Hub1 protein. This was because the Snu66 binding pocket of Hub1 is occupied by pH-sensitive residues, making it difficult to distinguish between pH-induced NMR shifts and actual binding events. The NMR analyses were therefore verified experimentally by microscale thermophoresis and by NMR pH titration experiments. Our study found two small peptides that showed binding to Hub1. These peptides are the first small-molecule ligands reported to interact with the Hub1 protein.

Evaluación de profilaxis con factor VIII de origen plasmático en pacientes con hemofilia A severa / Evaluation of factor VIII prophylaxis of plasmatic origin in patients with severe hemophilia A / Avaliação da profilaxia do fator VIII de origem plasmática em pacientes com hemofilia A grave

Introducción: la hemofilia A severa (HAS) es una enfermedad hemorrágica hereditaria causada por un déficit de factor VIII (FVIII) menor al 1%. Se presenta principalmente con sangrados articulares, los cuales provocan una artropatía hemofílica que afecta su independencia funcional. El uso de la profilaxis terciaria con FVIII ofrece beneficios en adultos disminuyendo la tasa anual de sangrado (TAS) y mejorando la independencia funcional. Objetivo: determinar el porcentaje de pacientes que logran mantener un nivel de FVIII mayor al 1%, conocer si existe una mejora en la independencia funcional, así como una disminución en la TAS con el régimen profiláctico empleado. Métodos: estudio observacional, analítico. Se incluyó a los pacientes con HAS que se controlaron en el Hospital de Clínicas "Dr. Manuel Quintela" durante 2020 en profilaxis con FVIII durante 12 meses. Se obtuvieron tres muestras separadas en el tiempo para dosificación de FVIII y se evaluó la TAS y la independencia funcional en cada paciente. Resultados: se analizaron ocho pacientes, todos presentaron valores de FVIII superiores al 1% a la hora y 24 horas posterior a la administración de FVIII. Los episodios de sangrado se redujeron 4,76 veces con el uso de la profilaxis (p = 0,019). La independencia funcional mostró que 5/8 pacientes mejoraron al menos 1 punto del score. Conclusiones: la profilaxis terciaria en estos pacientes fue beneficioso en reducir la TAS y mejorar su capacidad funcional.

Summary: Introduction: severe hemophilia A (SAH) is an hereditary hemorrhagic disease, caused by a factor VIII (FVIII) deficiency of less than 1%. It presents with joint bleeding mainly, which causes a hemophilic arthropathy, which affects its functional independence. The use of tertiary prophylaxis with FVIII offers benefits in adults by decreasing the annual bleeding rate (ABR) and improving functional independence. Objective: to determine the percentage of patients who manage to maintain an FVIII level greater than 1%, to know if there is an improvement in functional independence, as well as a decrease in the ABR with the prophylactic regimen used. Methods: observational, analytical study. Patients with SAH who were controlled at the Hospital de Clínicas "Dr. Manuel Quintela", during the year 2020, in prophylaxis with FVIII for 12 months were included. Three samples separated in time for FVIII dosing were obtained and the ABR and functional independence were evaluated in each patient. Results: 8 patients were analyzed, all presented FVIII higher than 1% at one hour and 24 hours after the administration of FVIII. The bleeding episodes were reduced 4.76 times with the use of Prophylaxis (p = 0.019). Functional independence showed that 5/8 patients improved at least 1 point in the Score. Conclusions: tertiary prophylaxis in these patients was beneficial in reducing SAD and improving their functional capacity.

Introdução: a hemofilia A grave (HAS) é uma doença hemorrágica hereditária, causada pela deficiência do fator VIII (FVIII) inferior a 1%. Apresenta-se principalmente com sangramento articular, que causa artropatia hemofílica, que afeta sua independência funcional. O uso de profilaxia terciária com FVIII oferece benefícios em adultos, reduzindo a taxa de sangramento anual (TAS) e melhorando a independência funcional. Objetivos: determinar a porcentagem de pacientes que conseguem manter um nível de FVIII maior que 1%, identificar uma possível melhora da independência funcional, bem como uma diminuição da TAS com o esquema profilático utilizado. Métodos: estudo observacional, analítico de pacientes com HAS controlados no Hospital das Clínicas "Dr. Manuel Quintela", durante o ano de 2020, em profilaxia com FVIII durante 12 meses. Foram obtidas três amostras separadas no tempo para dosagem de FVIII e avaliação da TAS e da independência funcional de cada paciente. Resultados: foram analisados 8 pacientes, todos apresentaram FVIII maior que 1% em uma hora e 24 horas após a administração do FVIII. Os episódios de sangramento foram reduzidos 4,76 vezes com o uso da profilaxia (p = 0,019). A independência funcional mostrou que 5/8 pacientes melhoraram pelo menos 1 ponto do escore FISH. Conclusões: a profilaxia terciária nesses pacientes foi benéfica na redução da TAS e na melhora da capacidade funcional.

Effect of EARLY administration of DEXamethasone in patients with COVID-19 pneumonia without acute hypoxemic respiratory failure and risk of development of acute respiratory distress syndrome (EARLY-DEX COVID-19): study protocol for a randomized controlled trial.

BACKGROUND: Corticosteroids are one of the few drugs that have shown a reduction in mortality in coronavirus disease 2019 (COVID-19). In the RECOVERY trial, the use of dexamethasone reduced 28-day mortality compared to standard care in hospitalized patients with suspected or confirmed COVID-19 requiring supplemental oxygen or invasive mechanical ventilation. Evidence has shown that 30% of COVID-19 patients with mild symptoms at presentation will progress to acute respiratory distress syndrome (ARDS), particularly patients in whom laboratory inflammatory biomarkers associated with COVID-19 disease progression are detected. We postulated that dexamethasone treatment in hospitalized patients with COVID-19 pneumonia without additional oxygen requirements and at risk of progressing to severe disease might lead to a decrease in the development of ARDS and thereby reduce death. METHODS/DESIGN: This is a multicenter, randomized, controlled, parallel, open-label trial testing dexamethasone in 252 adult patients with COVID-19 pneumonia who do not require supplementary oxygen on admission but are at risk factors for the development of ARDS. Risk for the development of ARDS is defined as levels of lactate dehydrogenase > 245 U/L, C-reactive protein > 100 mg/L, and lymphocyte count of < 0.80 × 109/L. Eligible patients will be randomly assigned to receive either dexamethasone or standard of care. Patients in the dexamethasone group will receive a dose of 6 mg once daily during 7 days. The primary outcome is a composite of the development of moderate or more severe ARDS and all-cause mortality during the 30-day period following enrolment. DISCUSSION: If our hypothesis is correct, the results of this study will provide additional insights into the management and progression of this specific subpopulation of patients with COVID-19 pneumonia without additional oxygen requirements and at risk of progressing to severe disease. TRIAL REGISTRATION: ClinicalTrials.gov NCT04836780. Registered on 8 April 2021 as EARLY-DEX COVID-19.

Deep compressed seismic learning for fast location and moment tensor inferences with natural and induced seismicity.

Fast detection and characterization of seismic sources is crucial for decision-making and warning systems that monitor natural and induced seismicity. However, besides the laying out of ever denser monitoring networks of seismic instruments, the incorporation of new sensor technologies such as Distributed Acoustic Sensing (DAS) further challenges our processing capabilities to deliver short turnaround answers from seismic monitoring. In response, this work describes a methodology for the learning of the seismological parameters: location and moment tensor from compressed seismic records. In this method, data dimensionality is reduced by applying a general encoding protocol derived from the principles of compressive sensing. The data in compressed form is then fed directly to a convolutional neural network that outputs fast predictions of the seismic source parameters. Thus, the proposed methodology can not only expedite data transmission from the field to the processing center, but also remove the decompression overhead that would be required for the application of traditional processing methods. An autoencoder is also explored as an equivalent alternative to perform the same job. We observe that the CS-based compression requires only a fraction of the computing power, time, data and expertise required to design and train an autoencoder to perform the same task. Implementation of the CS-method with a continuous flow of data together with generalization of the principles to other applications such as classification are also discussed.

Exploring the Surface of the Ectodomain of the PD-L1 Immune Checkpoint with Small-Molecule Fragments.

Development of small molecules targeting the PD-L1/PD-1 interface is advancing both in industry and academia, but only a few have reached early-stage clinical trials. Here, we take a closer look at the general druggability of PD-L1 using in silico hot spot mapping and nuclear magnetic resonance (NMR)-based characterization. We found that the conformational elasticity of the PD-L1 surface strongly influences the formation of hot spots. We deconstructed several generations of known inhibitors into fragments and examined their binding properties using differential scanning fluorimetry (DSF) and protein-based nuclear magnetic resonance (NMR). These biophysical analyses showed that not all fragments bind to the PD-L1 ectodomain despite having the biphenyl scaffold. Although most of the binding fragments induced PD-L1 oligomerization, two compounds, TAH35 and TAH36, retain the monomeric state of proteins upon binding. Additionally, the presence of the entire ectodomain did not affect the binding of the hit compounds and dimerization of PD-L1. The data demonstrated here provide important information on the PD-L1 druggability and the structure-activity relationship of the biphenyl core moiety and therefore may aid in the design of novel inhibitors and focused fragment libraries for PD-L1.

Biphenyl Ether Analogs Containing Pomalidomide as Small-Molecule Inhibitors of the Programmed Cell Death-1/Programmed Cell Death-Ligand 1 Interaction.

New biphenyl-based chimeric compounds containing pomalidomide were developed and evaluated for their activity to inhibit and degrade the programmed cell death-1/programmed cell death- ligand 1 (PD-1/PD-L1) complex. Most of the compounds displayed excellent inhibitory activity against PD-1/PD-L1, as assessed by the homogenous time-resolved fluorescence (HTRF) binding assay. Among them, compound 3 is one of the best with an IC50 value of 60 nM. Using an ex vivo PD-1/PD-L1 blockade cell line bioassay that expresses human PD-1 and PD-L1, we show that compounds 4 and 5 significantly restore the repressed immunity in this co-culture model. Western blot data, however, demonstrated that these anti-PD-L1/pomalidomide chimeras could not reduce the protein levels of PD-L1.

Physicochemical and Microbiological Stability of Two Oral Solutions of Methadone Hydrochloride 10 mg/mL.

In this article, we studied physicochemical and microbiological stability and determined the beyond-use date of two oral solutions of methadone in three storage conditions. For this, two oral solutions of methadone (10 mg/mL) were prepared, with and without parabens, as preservatives. They were packed in amber glass vials kept unopened until the day of the test, and in a multi-dose umber glass bottle opened daily. They were stored at 5 ± 3 °C, 25 ± 2 °C and 40 ± 2 °C. pH, clarity, and organoleptic characteristics were obtained. A stability-indicating high-performance liquid chromatography method was used to determine methadone. Microbiological quality was studied and antimicrobial effectiveness testing was also determined following European Pharmacopoeia guidelines. Samples were analyzed at days 0, 7, 14, 21, 28, 42, 56, 70, and 91 in triplicate. After 91 days of storage, pH remained stable at about 6.5-7 in the two solutions, ensuring no risk of methadone precipitation. The organoleptic characteristics remained stable (colorless, odorless, and bitter taste). The absence of particles was confirmed. No differences were found with the use of preservatives. Methadone concentration remained within 95-105% in all samples. No microbial growth was observed. Hence, the two oral methadone solutions were physically and microbiologically stable at 5 ± 3 °C, 25 ± 2 °C, and 40 ± 2 °C for 91 days in closed and opened amber glass bottles.