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The origins of low-temperature tissue storage research date back to the late 1800s. Over half a century later, osmotic stress was revealed to be a main contributor to cell death during cryopreservation. Consequently, the addition of cryoprotective agents (CPAs) such as dimethyl sulfoxide (DMSO), glycerol (GLY), ethylene glycol (EG), or propylene glycol (PG), although toxic to cells at high concentrations, was identified as a necessary step to protect against rampant cell death during cryopreservation. In addition to osmotic stress, cooling and thawing rates were also shown to have significant influence on cell survival during low temperature storage. In general, successful low-temperature cell preservation consists of the addition of a CPA (commonly 10% DMSO), alone or in combination with additional permeating or non-permeating agents, cooling rates of approximately 1ºC/min, and storage in either liquid or vapor phase nitrogen. In addition to general considerations, cell-specific recommendations for hepatocytes, pancreatic islets, sperm, oocytes, and stem cells should be observed to maximize yields. For example, rapid cooling is associated with better cryopreservation outcomes for oocytes, pancreatic islets, and embryonic stem cells while slow cooling is recommended for cryopreservation of hepatocytes, hematopoietic stem cells, and mesenchymal stem cells. Yields can be further maximized by implementing additional pre-cryo steps such as: pre-incubation with glucose and anti-oxidants, alginate encapsulation, and selecting cells within an optimal age range and functional ability. Finally, viability and functional assays are critical steps in determining the quality of the cells post-thaw and improving the efficiency of the current cryopreservation methods.

This study compared the chemical, structural, and luminescent properties of xerogel-based ceramic powders (CPs) with those of a new series of crystallized aerogels (CAs) synthesized by the epoxy-assisted sol–gel process. Materials with different proportions of Eu3+ (2, 5, 8, and 10 mol%) were synthesized in Lu2O3 host matrices, as well as a Eu2O3 matrix for comparative purposes. The products were analyzed by infrared spectroscopy (IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS), transmission electron microscopy (TEM), photoluminescence analysis, and by the Brunauer–Emmett–Teller (BET) technique. The results show a band associated with the M-O bond, located at around 575 cm−1. XRD enabled us to check two ensembles: matrices (Lu2O3 or Eu2O3) and doping (Lu2O3:Eu3+) with appropriate chemical compositions featuring C-type crystal structures and intense reflections by the (222) plane, with an interplanar distance of around 0.3 nm. Also, the porous morphology presented by the materials consisted of interconnected particles that formed three-dimensional networks. Finally, emission bands due to the energy transitions (5DJ, where J = 0, 1, 2, and 3) were caused by the Eu3+ ions. The samples doped at 10 mol% showed orange-pink photoluminescence and had the longest disintegration times and greatest quantum yields with respect to the crystallized Eu2O3 aerogel.

Nicotine and cannabis use during adolescence has the potential to induce long lasting changes on affective and cognitive function. Here, we examined whether adolescent exposure to nicotine, the cannabinoid agonist WIN55-212,2 (WIN), or co-exposure to both would alter operant learning, locomotion, and anxiety- and reward-related behaviors in male and female mice during adulthood. Males exposed to a moderate dose of WIN (2 mg/kg) or co-exposed to nicotine and the moderate dose of WIN exhibited decreased anxiety-associated behaviors and increased cognitive flexibility, but did not differ in operant learning or generalized locomotion. In contrast, differences were not found among the females in these measures at the moderate WIN dose or in both sexes with exposure to a low WIN dose (0.2 mg/kg). Furthermore, a sex-dependent dissociative effect was found in natural reward consumption. Males exposed to the moderate dose of WIN or co-exposed to nicotine and the moderate dose of WIN demonstrated increased sucrose consumption. In contrast, females exposed to the moderate dose of WIN exhibited a decrease in sucrose consumption, which was ameliorated with co-administration of nicotine. Together, these novel findings demonstrate that adolescent exposure to cannabinoids in the presence or absence of nicotine results in altered affective and reward-related behaviors during adulthood.

Background Weeksella virosa pneumonia is an infection that has been described as a healthcare-associated infection. This is a rare gram-negative anaerobic bacterium associated with the use of mechanical ventilation for a long period of time and is more frequent in immunosuppressed patients. This is the first case reported in the state of Veracruz and the second in Mexico. Case presentation We present the case of a 64-year-old female from Veracruz, Mexico who developed an infectious process in the right pelvic limb after a transcatheter aortic valve replacement procedure and subsequently developed sudden cardiorespiratory arrest requiring mechanical ventilation, with subsequent imaging studies demonstrating a pneumonic process associated with a nosocomial infection. Discussion and Conclusions We should take into consideration that this pathogen affects not only adults with multiple comorbidities but also children with renal, hepatic, or oncological pathologies, as well as immunocompromised patients, who should be considered high-risk populations for W. virosa infection.

Venous thromboembolism (VTE) is a common disease, which includes deep venous thrombosis (DVT) and pulmonary embolism (PE). It is the third most common cardiovascular disorder, affecting predominantly the male elderly population. Stress cardiomyopathy (SC) is a transitorily cardiovascular condition produced after an emotional or physical trigger, and it features signs and symptoms of acute coronary syndrome. Its pathophysiological mechanisms remain unclear, and SC has also been related to critical complications such as heart failure, arrhythmias, left ventricular outflow obstruction, and thromboembolic events. This case report highlights the association of PE and SC that might play a pathophysiological role.

BackgroundAcute coronary syndrome (ACS) is the leading cause of morbidity and mortality worldwide. The different reperfusion strategies have evolved over the years, and efforts have been directed to reduce its complications. Among these strategies, the one that has shown the best results is percutaneous coronary intervention, which has significantly improved the survival and prognosis of these patients; however, this procedure is not free of complications since multiple factors are involved. Among them is the time of patient care from the time of diagnosis until the coronary reperfusion therapy is performed.MethodologyIn this study, we describe the experience in our center with the 6-French Ikari Left guide catheter as a strategy of radial angiography-angioplasty with a single catheter to reduce the care times of patients with acute ST-elevation myocardial infarction (STEMI) in our center and compare it with the series reported by other international centers since. To establish an alternative to the usual approach that consists of the use of Judkins catheters, diagnosis, and guiding.ResultsOur study showed a success rate for diagnostic angiography and percutaneous coronary intervention (PCI) with the 6- French Ikari Left catheter comparable to those obtained in other centers, even with lower complication rates than the usual approach with Judkins’ Catheters.ConclusionsThe use of the 6-French Ikari Left catheter demonstrated shorter needle-device time and compared to other international series, it was shown to be shorter and related to shorter fluoroscopy time. Our study has a small sample and only included a highly selected population, which represents a limitation. This study is vulnerable to the different practices of the operators, with involvement in procedure time and use of contrast volume.

Abstract Background Cardiac myxomas are the most common primary benign tumour of the heart. Most of them occur between the 4th and 6th decade of life, are most frequent in the woman, and most frequently localized in the left atrium. Case summary We present a case of a 41-year-old female who presented with a history of left-sided heart failure. A left atrial mass of 87 × 88 × 65 mm was documented by cardiac magnetic resonance. She was taken to surgical resection of the mass. Histopathologic findings were diagnostic of cardiac myxoma. Generally, myxomas that are bigger than 6 cm are associated with the worst prognosis. Discussion Primary cardiac tumours are mostly benign, being in 50% of the cases a cardiac myxoma. The rest of them correspond to papillary fibroelastoma (26%), fibromas (6%), lipomas (4%), and others including calcified tumours, haemangiomas, teratomas, cysts, and rhabdomyomas. Our clinical case illustrates an unusual and rare presentation of cardiac myxoma with a double mitral lesion.

Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect any organ with a predisposition for women of reproductive age. It is related to a higher risk of cardiovascular events, increasing it up to 50 times in young people, and 30% of deaths are attributed to coronary artery disease. The risk of developing cardiovascular disease in SLE is related not only to traditional cardiovascular risks factors such as advanced age, hypertension, dyslipidemia, and diabetes but also to disease-specific factors, such as degree of activity, autoantibodies, organ damage, and treatment. Accelerated atherosclerosis is one of the main contributors to pathogenesis. Manifestations range from angina to acute myocardial infarction and sudden death. Markers have been studied for the detection of subclinical disease and stratification of these patients, as well as different treatment options to improve the cardiovascular prognosis of the disease.

Background The T-wave alterations are suggestive of ischemia, among them there is the pseudo-normalization (positivization of the T-wave, previously negative, during stress exercise). Myocardial single photon emission computed tomography (SPECT) at rest and stress is usually performed with Technetium 99 (Tc-99), which has high sensitivity and specificity for the detection of ischemic heart disease. In this study, we decided to investigate the patients who pseudo-normalized the T-wave in the stress test to correlate with the existence of ischemia diagnosed by myocardial perfusion study, specifically myocardial SPECT in perfusion and rest with Tc-99. Methodology T - wave pseudo-normalization patients who underwent a myocardial perfusion SPECT between January 2018 and June 2019 were included in this retrospective study. We analyzed 81 patients: 50 patients with pseudo-normalization of T-waves and 31 patients, as a control group, without pseudo-normalization. A descriptive analysis of the quantitative variables was performed using Student's t-test or Mann-Whitney U test, and for the qualitative variables, the χ2 test or Fisher's exact test was performed. Results The degree of ischemia according to the presence or absence of pseudo-normalization of the T-wave. The pseudo-normalization of the T-wave in the group without ischemia (48.4% vs. 36%), for the mild degree the proportions were the same (38.7% vs. 38%), the moderate degree it was slightly higher in the pseudo-normalization of the T-wave (9.7% vs. 18%) and severe (3.2% vs. 6%). Conclusions In this study, the relationship between pseudo-normalization of the T waveform and ischemia, predominantly moderate to severe, was demonstrated. However, it was not statistically significant due to the size of the sample studied.

The statistics of how the local environment of a particle looks like, e.g., given by the distribution of nearest neighbor distances or the sizes of Voronoi cells, is important as a starting point for the calculation of many material properties like electronic or photonic band structures. Here we study local environments that occur in quasicrystals with large rotational symmetry. Both with analytical considerations based on geometric arguments and with an analysis of a large number of numerically created patches of high-symmetry quasicrystals we find that the Voronoi area’s distribution reaches a bimodal curve and that in the limit of large rotational symmetries the distribution of nearest neighbor distance converges against a universal curve, where 27.7 % of the vertices have their nearest neighbor at a normalized distance equal to 1, while for the other 72.3 % the nearest neighbor is at a distance less than 1. Therefore, the statistics of local environments is non-trivial but independent of the specific rotational symmetry. Thus properties that only depend on local environments are expected to be universal for all high-symmetry quasicrystals.