Comparing organic and metallo-organic hydrazone molecular cages as potential carriers for doxorubicin delivery.

Molecular cages are three-dimensional supramolecular structures that completely wrap guest molecules by encapsulation. We describe a rare comparative study between a metallo-organic cage and a fully organic analogous system, obtained by hydrazone bond formation self-assembly. Both cages are able to encapsulate the anticancer drug doxorubicin, with the organic cage forming a 1 : 1 inclusion complex with µM affinity, whereas the metallo-organic host experiences disassembly by interaction with the drug. Stability experiments reveal that the ligands of the metallo-organic cage are displaced in buffer at neutral, acidic, and basic pH, while the organic cage only disassembles under acidic conditions. Notably, the organic cage also shows minimal cell toxicity, even at high doses, whilst the doxorubicin-cage complex shows in vitro anti-cancer activity. Collectively, these results show that the attributes of the pure organic molecular cage are suitable for the future challenges of in vivo drug delivery using molecular cages.

Sociodemographic and Lifestyle Characteristics Associated with Maternal Dietary Patterns in Mexico.

There is scarce evidence on sociodemographic and lifestyle characteristics that may explain adherence to different dietary patterns (DPs) during pregnancy. Our aims were to identify dietary patterns in a sample of pregnant Mexican women and to describe their association with selected sociodemographic and lifestyle characteristics. This is a secondary cross-sectional analysis of 252 mothers of children that participated as controls in a hospital-based case-control study of childhood leukemia. We obtained parents' information about selected sociodemographic characteristics, as well as alcohol and tobacco consumption. We also obtained dietary information during pregnancy. We identified DPs using cluster and factor analyses and we estimated their association with characteristics of interest. We identified two DPs using cluster analysis, which we called "Prudent" and "Non healthy", as well as three DPs through factor analysis, namely "Prudent", "Processed foods and fish", and "Chicken and vegetables". Characteristics associated with greater adherence to "Prudent" patterns were maternal education, older paternal age, not smoking, and being a government employee and/or uncovered population. Likewise, the "Processed foods and fish" pattern was associated with greater maternal and paternal education, as well as those with less household overcrowding. We did not identify sociodemographic variables related to the "Chicken and Vegetables" pattern. Our results may be useful to identify target populations that may benefit from interventions aimed to improve individual dietary decisions during pregnancy.

Vitamin D opposes multilineage cell differentiation induced by Notch inhibition and BMP4 pathway activation in human colon organoids.

Understanding the mechanisms involved in colonic epithelial differentiation is key to unraveling the alterations causing inflammatory conditions and cancer. Organoid cultures provide an unique tool to address these questions but studies are scarce. We report a differentiation system toward enterocytes and goblet cells, the two major colonic epithelial cell lineages, using colon organoids generated from healthy tissue of colorectal cancer patients. Culture of these organoids in medium lacking stemness agents resulted in a modest ultrastructural differentiation phenotype with low-level expression of enterocyte (KLF4, KRT20, CA1, FABP2) and goblet cell (TFF2, TFF3, AGR2) lineage markers. BMP pathway activation through depletion of Noggin and addition of BMP4 resulted in enterocyte-biased differentiation. Contrarily, blockade of the Notch pathway using the γ-secretase inhibitor dibenzazepine (DBZ) favored goblet cell differentiation. Combination treatment with BMP4 and DBZ caused a balanced strong induction of both lineages. In contrast, colon tumor organoids responded poorly to BMP4 showing only weak signals of cell differentiation, and were unresponsive to DBZ. We also investigated the effects of 1α,25-dihydroxyvitamin D3 (calcitriol) on differentiation. Calcitriol attenuated the effects of BMP4 and DBZ on colon normal organoids, with reduced expression of differentiation genes and phenotype. Consistently, in normal organoids, calcitriol inhibited early signaling by BMP4 as assessed by reduction of the level of phospho-SMAD1/5/8. Our results show that BMP and Notch signaling play key roles in human colon stem cell differentiation to the enterocytic and goblet cell lineages and that calcitriol modulates these processes favoring stemness features.

The 2021 Global Initiative for Chronic Obstructive Pulmonary Disease (GOLD) guidelines and the outpatient management: Examining physician adherence and its effects on patient outcome.

Background: Chronic obstructive pulmonary disease (COPD) is a common preventable illness that carries a large global economic and social burden. The global initiative for chronic obstructive lung disease (GOLD) guidelines has been utilized as a global strategy for the continued COPD diagnosis, assessment, and treatment. We aimed to determine if the adherence to the 2021 GOLD guideline directed management influenced outcomes. Materials and Methods: Retrospective medical records review of adult patients with COPD, who received care in our office during the entire year of 2021. Patients managed as per the 2021 GOLD guidelines were compared with those who received usual care. Results: Among 242 patients, 171 (70.7%) were GOLD management adherent (GA) and 71 (29.3%) were GOLD non-adherent (GNA). Certain comorbidities were associated with higher frequencies in the GA group, such as allergic rhinitis (63.2 vs. 18.3%; P < 0.001), coronary artery disease (55.9 vs. 38.0%; P = 0.011), GERD (63.2 vs. 32.4%; P < 0.001), anemia (38.6 vs. 19.7%; P = 0.004), malignancy (34.5 vs. 19.7%; P = 0.023), and immunodeficiency (12.3 vs. 1.4%; P = 0.007). There was no significant difference in the mortality between the GA and GNA groups (5.3 vs. 9.9%; P = 0.254). Although the frequency of number of exacerbations was greater in the GA group, the difference in the mean number of exacerbations was not statistically significant (0.39 ± 1.08 vs. 0.39 ± 1.14; P = 0.984). Conclusion: We found no significant difference in the patient outcomes, such as number of exacerbations of COPD and mortality, when comparing the 2021 GOLD guideline adherent versus GOLD guideline non-adherent management of COPD.

Epidemiology of childhood acute leukemias in marginalized populations of the central-south region of Mexico: results from a population-based registry.

Introduction: Acute leukemias (AL) are the main types of cancer in children worldwide. In Mexico, they represent one of the main causes of death in children under 20 years of age. Most of the studies on the incidence of AL in Mexico have been developed in the urban context of Greater Mexico City and no previous studies have been conducted in the central-south of the country through a population-based study. The aim of the present work was to identify the general and specific incidence rates of pediatric AL in three states of the south-central region of Mexico considered as some of the marginalized populations of Mexico (Puebla, Tlaxcala, and Oaxaca). Methods: A population-based study was conducted. Children aged less than 20 years, resident in these states, and newly diagnosed with AL in public/private hospitals during the period 2021-2022 were identified. Crude incidence rates (cIR), standardized incidence rates (ASIRw), and incidence rates by state subregions (ASIRsr) were calculated. Rates were calculated using the direct and indirect method and reported per million children under 20 years of age. In addition, specific rates were calculated by age group, sex, leukemia subtype, and immunophenotype. Results: A total of 388 cases with AL were registered. In the three states, the ASIRw for AL was 51.5 cases per million (0-14 years); in Puebla, it was 53.2, Tlaxcala 54.7, and Oaxaca de 47.7. In the age group between 0-19 years, the ASIRw were 44.3, 46.4, 48.2, and 49.6, in Puebla, Tlaxcala, and Oaxaca, respectively. B-cell acute lymphoblastic leukemia was the most common subtype across the three states. Conclusion: The incidence of childhood AL in the central-south region of Mexico is within the range of rates reported in other populations of Latin American origin. Two incidence peaks were identified for lymphoblastic and myeloid leukemias. In addition, differences in the incidence of the disease were observed among state subregions which could be attributed to social factors linked to the ethnic origin of the inhabitants. Nonetheless, this hypothesis requires further investigation.

[A case of abdominal internal hernia through the foramen of Winslow in a pediatric emergency department].

Abdominal internal hernia is a rare cause of intestinal obstruction in pediatric emergency departments, being the herniation through the foramen of Winslow an exceptional entity (less than 0.5% of the herniae). We report the case of a 15-year-old adolescent male without previous surgical interventions who presented with abdominal pain and vomiting; computed tomography scans showed intestinal obstruction due to an internal hernia through the foramen of Winslow. To reduce the herniated ileum, the patient required surgical intervention with diagnostic laparoscopy, which, due to bad visualization, was changed to supraumbilical midline laparotomy. There was no need to resect the affected ileum as it appeared healthy. We did not perform a preventive technique to reduce the risk of recurrence. Postoperative pelvic collection was conservatively managed with antibiotics. The patient undergoes regular follow-up in the pediatric surgery department.

Evidence of spatial clustering of childhood acute lymphoblastic leukemia cases in Greater Mexico City: report from the Mexican Inter-Institutional Group for the identification of the causes of childhood leukemia.

Background: A heterogeneous geographic distribution of childhood acute lymphoblastic leukemia (ALL) cases has been described, possibly, related to the presence of different environmental factors. The aim of the present study was to explore the geographical distribution of childhood ALL cases in Greater Mexico City (GMC). Methods: A population-based case-control study was conducted. Children <18 years old, newly diagnosed with ALL and residents of GMC were included. Controls were patients without leukemia recruited from second-level public hospitals, frequency-matched by sex, age, and health institution with the cases. The residence address where the patients lived during the last year before diagnosis (cases) or the interview (controls) was used for geolocation. Kulldorff's spatial scan statistic was used to detect spatial clusters (SCs). Relative risks (RR), associated p-value and number of cases included for each cluster were obtained. Results: A total of 1054 cases with ALL were analyzed. Of these, 408 (38.7%) were distributed across eight SCs detected. A relative risk of 1.61 (p<0.0001) was observed for the main cluster. Similar results were noted for the remaining seven ones. Additionally, a proximity between SCs, electrical installations and petrochemical facilities was observed. Conclusions: The identification of SCs in certain regions of GMC suggest the possible role of environmental factors in the etiology of childhood ALL.

Evaluation of an automatized AMBU ESSI-1 INC designed at the Instituto Nacional de Cardiología Ignacio Chávez / Evaluación del AMBU automatizado ESSI-1 INC diseñado en el Instituto Nacional de Cardiología Ignacio Chávez

Abstract Objective: The objectives of this study were to evaluate an automated device for ventilatory support based on AMBU manufactured in March 2020. Methods: The ESSI-1 INC was evaluated through pulmonary mechanics and physiology parameters through compensatory spirometer tests (TISSOTs), and an artificial lung Model5600i Dual Adult PNEU VIEW SYSTEM; it was also compared to the anesthetic ventilatory support equipment (AEONMED 7500) in porcine models, measuring ventilatory, hemodynamic and gasometric parameters. Results: This equipment (ESSI-1 INC) was successfully tested by mechanical and biological models, such as pigs in which its performance was evaluated in terms of variability of tidal volume, ventilation frequency, and I/E relationship versus the manual performance of two medical interns. All the results turned out as expected and were satisfactory. Conclusions: It is safe and effective equipment and should be tested and used in diverse clinical conditions to standardize the ventilatory safety and care of patients who require it.

Resumen Objetivo: Evaluar un dispositivo automatizado para la asistencia ventilatoria basado en un AMBU manufacturado en Marzo del 2020. Métodos: El ESSI-1 INC fue evaluado por medio de parámetros fisiológicos y mecánica pulmonar a través de pruebas de espirómetro compensatorios (TISSOT); pulmón artificial (Modelo 5600i Dual Adult PNEU VIEW SYSTEM); así como su desempeño comparado a la máquina de anestesia (AEONMED 7500) en modelos porcinos, midiendo criterios ventilatorios, hemodinámicos y gasométricos. Resultados: Este equipo (ESSI-1 INC) fue exitosamente probado por modelos mecánicos y biológicos, tales como cerdos donde su desempeño fue evaluado en términos de la variabilidad del volumen tidal, frecuencia ventilatoria, y relación I/E versus el desempeño manual de dos médicos. Todos los resultados finalizaron como se esperaba de forma satisfactoria. Conclusiones: Es un equipo seguro y efectivo, el cual debería ser probado y usado en distintas condiciones clínicas para estandarizar la seguridad ventilatoria y cuidado de pacientes que lo requieran.

Maternal dietary patterns and acute leukemia in infants: results from a case control study in Mexico.

Background: Childhood cancer is the leading cause of disease-related mortality among children aged 5-14 years in Mexico, with acute leukemia being the most common cancer among infants. Examining the overall dietary patterns allows for a comprehensive assessment of food and nutrient consumption, providing a more predictive measure of disease risk than individual foods or nutrients. This study aims to evaluate the association between maternal dietary patterns during pregnancy and the risk of acute leukemia in Mexican infants. Methods: A hospital-based case-control study was conducted, comparing 109 confirmed acute leukemia cases with 152 age-matched controls. All participants (≤24 months) were identified at hospitals in Mexico City between 2010 and 2019. Data on a posteriori dietary patterns and other relevant variables were collected through structured interviews and dietary questionnaires. Multivariate logistic regression was employed to estimate the association between maternal dietary patterns during pregnancy and the risk of acute leukemia in infants. Results: The "Balanced & Vegetable-Rich" pattern, characterized by a balanced consumption of various food groups and higher vegetable intake, exhibited a negative association with acute leukemia when compared to the "High Dairy & Cereals" Pattern (adjusted odds ratio [OR] = 0.51; 95% confidence interval [CI]: 0.29, 0.90). We observed that mothers who gave birth to girls and adhered to a healthy dietary pattern during pregnancy exhibited significantly lower odds of their children developing AL compared to those who gave birth to boys [OR = 0.32 (95% CI 0.11, 0.97)]. Our results underscore the significance of maternal nutrition as a modifiable factor in disease prevention and the importance of prenatal health education.

HPLC-UV evaluation of a microwave assisted method as an active drug loading technique for exosome-based drug delivery system.

This paper evaluates the potential of a microwave radiation (MR) assisted method as an active drug loading technique for exosomes using polyphenolic nutraceuticals as model drugs (i.e. resveratrol (RV), rosmarinic acid (RA), pterostilbene (PT) and epigallocatechin gallate (EG)). MR is evaluated as a single step method and as part of a two-step method consisting of incubation (IN) followed by MR. The effect of exposure time, loading method and type of nutraceutical on the loading efficiency were investigated using high performance liquid chromatography (HPLC), X-ray diffraction (XRD) and flow cytometry. Additionally, dynamic light scattering (DLS) was used to determine the size of exosomes. Loading efficiency results indicated that MR is a promising method to be used as loading process. Results also suggested that due to different levels of hydrophobicity, related to the number of OH groups, the absorption of polyphenols into the bilayer of EVs is different for each molecule. According to XRD results, MR could not be used with any cargo drug since radiation could affect the chemical composition and the degree of crystallinity of such molecules, consequently affecting their performance. Flow cytometry results indicated that loading methods negatively affect exosome concentration.

Porfiria cutánea tarda que simula esclerosis sistémica progresiva / Porphyria cutanea tarda mimicking progressive systemic sclerosis

Resumen Los síndromes esclerodermiformes suelen imitar muy bien una esclerosis sistémica progresiva, y es la presencia de ampollas cutáneas en áreas fotoexpuestas con hiperpigmentación los datos diferenciales para diagnosticar una porfiria. Presentamos el caso de un varón de 48 años con fotosensibilidad, fragilidad capilar, ampollas cutáneas e hiperpigmentación asociado a esclerodactilia, con pérdida cicatrizal distal de tejido en los dedos de las manos, que simuló a la perfección una esclerosis sistémica progresiva. La analítica mostró negatividad para anticuerpos antinucleares, antitopoisomerasa y anticentrómero, con valores altos de uroporfirinas en orina. El tratamiento con flebotomías e hidroxicloquina mejoró la fotosensibilidad y la fragilidad cutánea.

Abstract Sclerodermiform syndromes usually mimic progressive systemic sclerosis very well, with the presence of skin blisters in photo-exposed areas with hyperpigmentation being the differential data for diagnosing porphyria. We present the case of a 48-year old man with photosensitivity, capillary fragility, skin blisters, and hyperpigmentation associated with sclerodactyly with distal scar tissue loss on the fingers, which perfectly simulated progressive systemic sclerosis. The analysis showed negativity for antinuclear, antitopoisomerase and anticentromere antibodies, with high levels of uroporphyrins in urine. Phlebotomy and hydroxycloquine treatment improved photosensitivity and skin fragility.

A protective maternal nutrient concomitant intake associated with acute leukemia might be modified by sex, in children under 2 years.

Introduction: Maternal dietary consumption during pregnancy has been inconclusively associated with acute leukemia (AL) in infants, probably because epidemiological evidence has emerged mainly from the analysis of one-by-one nutrient, which is not a real-life scenario. Our objective was to evaluate the association between AL in Mexican children under 2 years of age and their mothers' nutrients concomitant intake during pregnancy, as well as to explore whether there are differences between girls and boys. Methods: We conducted a study of 110 cases of AL and 252 hospital-based controls in the Mexico City Metropolitan area from 2010 to 2019. We obtained information on maternal intake of 32 nutrients by a food frequency questionnaire and used weighted quantile sum regression to identify nutrient concomitant intakes. Results: We found a concomitant intake of nutrients negatively associated with AL (OR 0.17; CI95% 0.03,0.88) only among girls; and we did not find a nutrient concomitant intake positively associated with AL. Discussion: This is the first study that suggests nutrients that have been individually associated with AL are not necessarily the same in the presence of other nutrients (concomitant intake); as well as that maternal diet might reduce AL risk only in girls.

Biomaterials are the key to unlock spheroid function and therapeutic potential.

Spheroids are three-dimensional cell aggregates that mimic fundamental aspects of the native tissue microenvironment better than single cells, making them a promising platform for the study of tissue development and therapeutics. Spheroids have been investigated for decades as models in cancer research, yet we have only just scratched the surface of their potential clinical utility in cell-based therapies. Like many cells, spheroids commonly exhibit a loss of key attributes upon implantation, motivating the need for strategies to regulate their function in situ. Biomaterials offer numerous opportunities to preserve spheroid function and guide spheroid behavior by tailoring the local microenvironment.

Serotonin secretion by blood platelets: accuracy of high-performance liquid chromatography-electrochemical technique compared with the isotopic test and use in a clinical laboratory.

Background: Mild secretion defects are the most frequent and challenging blood platelet disorders to diagnose. Most δ-granule secretion tests lack validation, are not quantitative, or have unreliable response to weak platelet agonists. Objectives: To compare platelet serotonin secretion by HPLC-electrochemical detection technique (HPLC-ECD) with the reference isotopic test (3H-5-HT), evaluating its performance in clinical laboratories. Methods: The assay validation followed STARD-2015 recommendations. HPLC-ECD measured the nonsecreted serotonin remaining in platelet pellets after aggregation, comparing it with the reference 3H-5-HT assay. We studied subjects with inherited and aspirin-induced blood platelet disorders and assessed the HPLC-ECD operation for routine clinical diagnosis. Results: Calibration curves were linear (R2 = 0.997), with SD for residuals of 3.91% and analytical sensitivity of 5ng/mL. Intra- and interassay imprecision bias ranged between -8.5% and 2.1% and -9% and 3.1%, respectively. Serotonin recovery and stability were >95%, and the variability range of measurements was -5.5% to 4.6%. Statistical differences detected between tests were biologically irrelevant, with bias of 1.48% (SD, 8.43) and CI agreement of -18% to 15%. Both assays distinctly detected platelet secretion induced by 10 µM epinephrine and 4 µmM adenosine diphosphate. However, HPLC-ECD is quantitative and more sensitive to low serotonin content in blood platelets. Reference cutoffs for each agonist were determined in 87 subjects. Initially, the HPLC-ECD requires relatively expensive equipment and trained operators but has remarkably cheap running costs and a turn-around time of 24-36 hours. We have used this diagnostic tool routinely for >8 years. Conclusion: HPLC-ECD assay for platelet serotonin secretion is highly accurate, has advantages over the reference 3H-5-HT test, and is suitable as a clinical laboratory technique.

Large-scale antibody immune response mapping of splenic B cells and bone marrow plasma cells in a transgenic mouse model.

Molecular characterization of antibody immunity and human antibody discovery is mainly carried out using peripheral memory B cells, and occasionally plasmablasts, that express B cell receptors (BCRs) on their cell surface. Despite the importance of plasma cells (PCs) as the dominant source of circulating antibodies in serum, PCs are rarely utilized because they do not express surface BCRs and cannot be analyzed using antigen-based fluorescence-activated cell sorting. Here, we studied the antibodies encoded by the entire mature B cell populations, including PCs, and compared the antibody repertoires of bone marrow and spleen compartments elicited by immunization in a human immunoglobulin transgenic mouse strain. To circumvent prior technical limitations for analysis of plasma cells, we applied single-cell antibody heavy and light chain gene capture from the entire mature B cell repertoires followed by yeast display functional analysis using a cytokine as a model immunogen. We performed affinity-based sorting of antibody yeast display libraries and large-scale next-generation sequencing analyses to follow antibody lineage performance, with experimental validation of 76 monoclonal antibodies against the cytokine antigen that identified three antibodies with exquisite double-digit picomolar binding affinity. We observed that spleen B cell populations generated higher affinity antibodies compared to bone marrow PCs and that antigen-specific splenic B cells had higher average levels of somatic hypermutation. A degree of clonal overlap was also observed between bone marrow and spleen antibody repertoires, indicating common origins of certain clones across lymphoid compartments. These data demonstrate a new capacity to functionally analyze antigen-specific B cell populations of different lymphoid organs, including PCs, for high-affinity antibody discovery and detailed fundamental studies of antibody immunity.

Chaperone Activity and Protective Effect against Aß-Induced Cytotoxicity of Artocarpus camansi Blanco and Amaranthus dubius Mart. ex Thell Seed Protein Extracts.

Alzheimer's disease (AD) is the most common type of dementia and is listed as the sixth-leading cause of death in the United States. Recent findings have linked AD to the aggregation of amyloid beta peptides (Aß), a proteolytic fragment of 39-43 amino acid residues derived from the amyloid precursor protein. AD has no cure; thus, new therapies to stop the progression of this deadly disease are constantly being searched for. In recent years, chaperone-based medications from medicinal plants have gained significant interest as an anti-AD therapy. Chaperones are responsible for maintaining the three-dimensional shape of proteins and play an important role against neurotoxicity induced by the aggregation of misfolded proteins. Therefore, we hypothesized that proteins extracted from the seeds of Artocarpus camansi Blanco (A. camansi) and Amaranthus dubius Mart. ex Thell (A. dubius) could possess chaperone activity and consequently may exhibit a protective effect against Aß1-40-induced cytotoxicity. To test this hypothesis, the chaperone activity of these protein extracts was measured using the enzymatic reaction of citrate synthase (CS) under stress conditions. Then, their ability to inhibit the aggregation of Aß1-40 using a thioflavin T (ThT) fluorescence assay and DLS measurements was determined. Finally, the neuroprotective effect against Aß1-40 in SH-SY5Y neuroblastoma cells was evaluated. Our results demonstrated that A. camansi and A. dubius protein extracts exhibited chaperone activity and inhibited Aß1-40 fibril formation, with A. dubius showing the highest chaperone activity and inhibition at the concentration assessed. Additionally, both protein extracts showed neuroprotective effects against Aß1-40-induced toxicity. Overall, our data demonstrated that the plant-based proteins studied in this research work can effectively overcome one of the most important characteristics of AD.

Infarto pulmonar cavitado en mujer con lupus eritematoso sistémico asociado a síndrome antifosfolípido

Tanto lupus eritematoso sistémico como el síndrome antifosfolípido son enfermedades autoinmunes con potencial tromboembólico, sobre todo por la presencia de anticuerpos trombogénicos. El pulmón es un lugar común donde suele asentarse un trombo y generar una tromboembolia, a veces con posterior infarto y cavitación. Existen pocos estudios que informen un infarto pulmonar cavitado en un paciente con lupus asociado a síndrome antifosfolípido. Presentamos el caso de una mujer de 24 años con síntomas generales y lesión pulmonar derecha cavitada. Fue tratada inicialmente como infección tuberculosa o fúngica. La analítica y las imágenes orientaron y diagnosticaron lupus asociado a síndrome antifosfolípido, complicado con tromboembolismo pulmonar que luego pasó a cavitarse. La paciente mejoró considerablemente con anticoagulantes, corticoides y ciclofosfamida.

Both systemic lupus erythematosus and antiphospholipid syndrome are autoimmune diseases with thromboembolic potential, especially due to the presence of thrombogenic antibodies. The lung is a common place where a thrombus usually settles and generates a thromboembolism, sometimes with subsequent infarction and cavitation. There are few studies reporting cavitary pulmonary infarction in a patient with lupus associated with antiphospholipid syndrome. We present the case of a 24-year-old woman with general symptoms and cavitated right lung lesion. She was initially treated as tuberculous or fungal infection. Laboratory tests and images guided and diagnosed lupus associated with antiphospholipid syndrome, complicated by pulmonary thromboembolism that later became cavitated. The patient improved considerably with anticoagulants, corticosteroids, and cyclophosphamide.

Development of PCL PolyHIPE Substrates for 3D Breast Cancer Cell Culture.

Cancer is a becoming a huge social and economic burden on society, becoming one of the most significant barriers to life expectancy in the 21st century. In particular, breast cancer is one of the leading causes of death for women. One of the most significant difficulties to finding efficient therapies for specific cancers, such as breast cancer, is the efficiency and ease of drug development and testing. Tissue-engineered (TE) in vitro models are rapidly developing as an alternative to animal testing for pharmaceuticals. Additionally, porosity included within these structures overcomes the diffusional mass transfer limit whilst enabling cell infiltration and integration with surrounding tissue. Within this study, we investigated the use of high-molecular-weight polycaprolactone methacrylate (PCL-M) polymerised high-internal-phase emulsions (polyHIPEs) as a scaffold to support 3D breast cancer (MDA-MB-231) cell culture. We assessed the porosity, interconnectivity, and morphology of the polyHIPEs when varying mixing speed during formation of the emulsion, successfully demonstrating the tunability of these polyHIPEs. An ex ovo chick chorioallantoic membrane assay identified the scaffolds as bioinert, with biocompatible properties within a vascularised tissue. Furthermore, in vitro assessment of cell attachment and proliferation showed promising potential for the use of PCL polyHIPEs to support cell growth. Our results demonstrate that PCL polyHIPEs are a promising material to support cancer cell growth with tuneable porosity and interconnectivity for the fabrication of perfusable 3D cancer models.

Cyclic Stretch-Induced Mechanical Stress Applied at 1 Hz Frequency Can Alter the Metastatic Potential Properties of SAOS-2 Osteosarcoma Cells.

Recently, there has been an increasing focus on cellular morphology and mechanical behavior in order to gain a better understanding of the modulation of cell malignancy. This study used uniaxial-stretching technology to select a mechanical regimen able to elevate SAOS-2 cell migration, which is crucial in osteosarcoma cell pathology. Using confocal and atomic force microscopy, we demonstrated that a 24 h 0.5% cyclic elongation applied at 1 Hz induces morphological changes in cells. Following mechanical stimulation, the cell area enlarged, developing a more elongated shape, which disrupted the initial nuclear-to-cytoplasm ratio. The peripheral cell surface also increased its roughness. Cell-based biochemical assays and real-time PCR quantification showed that these morphologically induced changes are unrelated to the osteoblastic differentiative grade. Interestingly, two essential cell-motility properties in the modulation of the metastatic process changed following the 24 h 1 Hz mechanical stimulation. These were cell adhesion and cell migration, which, in fact, were dampened and enhanced, respectively. Notably, our results showed that the stretch-induced up-regulation of cell motility occurs through a mechanism that does not depend on matrix metalloproteinase (MMP) activity, while the inhibition of ion-stretch channels could counteract it. Overall, our results suggest that further research on mechanobiology could represent an alternative approach for the identification of novel molecular targets of osteosarcoma cell malignancy.

Acute Viral Pericarditis Complicated by Cardiac Tamponade as a Result of COVID-19.

Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) and coronavirus disease 2019 (COVID-19) predominantly cause respiratory symptoms but cardiovascular complications from COVID-19 have been documented in the literature. Acute pericarditis has been known to be caused by COVID-19 but severe cardiac complications, such as cardiac tamponade, have rarely been reported. Early diagnosis and treatment with pericardiocentesis are imperative, as this can improve patient outcomes. A 56-year-old female presented with chest pain and recurrent episodes of presyncope. The patient tested positive for SARS-Cov-2 through a polymerase chain reaction (PCR) test. The patient was hypotensive on arrival and the initial workup with electrocardiogram was significant for sinus tachycardia with low voltage QRS complexes in the precordial and limb leads. A transthoracic echocardiogram was also done and showed a large circumferential pericardial effusion with chamber collapse of the right atrium and right ventricle during diastole indicative of tamponade physiology. The patient's clinical course was complicated by pulseless electrical activity cardiac arrest during which a pericardiocentesis was done. One hundred (100) mL of serous pericardial fluid was drained and a return of spontaneous circulation was obtained after roughly 10 minutes of cardiopulmonary resuscitation. Further infectious and noninfectious workups, including malignant and rheumatologic etiologies for acute pericarditis, were negative. The patient was subsequently treated with high-dose non-steroidal anti-inflammatory drugs (NSAIDs) and colchicine for viral pericarditis. The patient's clinical course improved, and the patient was subsequently discharged after a prolonged hospital course to a subacute rehabilitation facility to undergo physical therapy.