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Bovine pericardium (BP) is widely used as a biomaterial for tissue engineering. Glutaraldehyde and formaldehyde are commonly employed in the reticulation processes to enhance the material's resistance and preservation. In this study, we assessed the impact of long-term storage in 4% formaldehyde on the quantitative expression of immunophenotypic markers in glutaraldehyde-treated BP. Histologic and immunohistochemical analyses were performed on 2 BP patches, manufactured in 2009 and 2020, respectively. Braile Biomédica provided the BP patches. Sections of BP were stained with H&E, Weigert, and picrosirius red, followed by immunolabeling for vimentin, laminin 5, collagen I, and collagen IV using a standardized protocol. Microscopic images were captured using light and polarized microscopy, and the area of the antibody signal was quantified using Image J Software. Histologic analysis showed no autolysis or significant changes in the patches. Immunohistochemical analysis revealed a diffuse distribution of collagen I and collagen IV throughout the connective tissue of the patches. The 2020 specimen exhibited higher expression levels of collagen I (21.36%) and collagen IV (24.67%) compared with the 2009 specimen (collagen I: 15.87%; collagen IV: 12.02%). Laminin did not show reactivity in either specimen. Notably, vimentin immunopositivity differed significantly between the patches, with a larger area of expression observed in the 2020 patch (54%) compared with the 2009 patch (13%). In summary, there were no substantial differences in immunophenotypic expression between the 2009 and 2020 BP patches, except for the higher vimentin expression in the 2020 BP patch., Competing Interests: The authors declare no conflict of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

The frequent and sudden increase of load in electric vehicles depletes oxygen from the fuel cell cathode, leading possibly to oxygen starvation. This paper presents the design of an air flow controller for fuel cell systems (FCS) that aims to replenish the depleted oxygen. A dynamic inversion is used as the feed-forward compensation for the disturbance effect coming from the load current change. However, the inverted dynamics have negative relative degree (improper) and not physically realizable. To make it proper, an augmentation by delay is done, with the same delay added into demand current. The current-dependent time delay introduced in the demand current gives the FCS the opportunity to prepare a sufficient air flow that can withstand the dip in oxygen excess ratio (OER). Besides, the FCS plant is linearized at various operating points, and the dynamic feedforward controller is designed at several operating points with interpolation applied for in-between values. The simulation results show a considerable improvement in the OER response where the constraint is met and the recovery time is reduced., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 ISA. Published by Elsevier Ltd. All rights reserved.)

Introduction: Clefts of the lip and palate are leading congenital facial anomalies. Underserved patients with these facial differences lack access to medical care, surgical expertise, prenatal care, or psychological support. Moreover, the disease results in significant economic strains on patients and their families. While surgical outreach programs have attempted to fill this void, significant challenges facing international comprehensive cleft care persist., Objective: Propose a path toward international sustainable cleft care based on the Global Smile Foundation experience., Results: International sustainable comprehensive cleft care can be achieved by regulating surgical outreach programs. Regulation of these missions would ensure standardized care and encourage stakeholders to cooperate and adequately allocate funding and resources. Capacity building can be achieved through "diagonal" cleft care delivery models, multidisciplinary workshops, fellowship programs, research and quality assurance, as well as leveraging emerging technologies such as Augmented Reality., Conclusion: International comprehensive cleft care requires continuous collaborative efforts between visiting and local teams as well as international and national organizations. Standardizing and regulating current practices as well as promoting capacity building initiatives can contribute to sustainable cleft care.

Advancements in surgical wound treatment have led to skin substitutes and bioscaffolds as temporary and permanent coverage for burn wounds. Skin substitutes are used to improve wound coverage and restore the functional and aesthetic qualities of skin, and help to prevent wound infection and maintain a moist wound healing environment. Although allografts are preferred when autografts are not possible, high costs and limited availability have led to the use of xenografts and the development of skin substitutes and bioscaffolds. Despite constant evolution in the development of these skin substitutes and bioscaffolds, no single product stands out as the gold standard., (Copyright © 2017 Elsevier Inc. All rights reserved.)

To examine microbe-mineral interactions in subsurface oceanic crust, we evaluated microbial colonization on crustal minerals that were incubated in borehole fluids for 1 year at the seafloor wellhead of a crustal borehole observatory (IODP Hole U1301A, Juan de Fuca Ridge flank) as compared to an experiment that was not exposed to subsurface crustal fluids (at nearby IODP Hole U1301B). In comparison to previous studies at these same sites, this approach allowed assessment of the effects of temperature, fluid chemistry, and/or mineralogy on colonization patterns of different mineral substrates, and an opportunity to verify the approach of deploying colonization experiments at an observatory wellhead at the seafloor instead of within the borehole. The Hole U1301B deployment did not have biofilm growth, based on microscopy and DNA extraction, thereby confirming the integrity of the colonization design against bottom seawater intrusion. In contrast, the Hole U1301A deployment supported biofilms dominated by Epsilonproteobacteria (43.5% of 370 16S rRNA gene clone sequences) and Gammaproteobacteria (29.3%). Sequence analysis revealed overlap in microbial communities between different minerals incubated at the Hole U1301A wellhead, indicating that mineralogy did not separate biofilm structure within the 1-year colonization experiment. Differences in the Hole U1301A wellhead biofilm community composition relative to previous studies from within the borehole using similar mineral substrates suggest that temperature and the diffusion of dissolved oxygen through plastic components influenced the mineral colonization experiments positioned at the wellhead. This highlights the capacity of low abundance crustal fluid taxa to rapidly establish communities on diverse mineral substrates under changing environmental conditions such as from temperature and oxygen.

Background: Despite several prophylactic strategies, postoperative venous thromboembolism (VTE) remains a major cause of morbidity and mortality. Therefore, the search for modifiable preoperative risk factors is crucial. Few reports have explored this issue but the direct relationship between preoperative steroid use and postoperative VTE in surgical patients remains unexplored., Methods: We used The American College of Surgeons' National Surgical Quality Improvement Program (NSQIP) database in our study. After analyzing patient characteristics, we used multivariate logistic regression to assess the crude and adjusted effect of steroids on VTE, our primary outcome., Results: Data was obtained for 1,921,901 patients, 58,667 of whom were on glucocorticoids for at least 30days preoperatively. VTE was higher in patients on steroids with an adjusted odds ratio of 1.54, 95% confidence interval (CI) 1.45-1.64. The adjusted odds ratio for the secondary outcomes: mortality, urinary tract occurrences, wound occurrences, sepsis, cardiac and respiratory adverse events were 1.42 (CI 1.35-1.49), 1.40 (CI 1.30-1.50), 1.58 (CI 1.51-1.66), 1.51 (CI 1.42-1.60), 1.19 (CI 1.11-1.29) and 1.302 (CI 1.301-1.303) respectively., Conclusions: Our results suggest that surgical patients with prolonged preoperative glucocorticoid intake are at a higher risk of developing postoperative VTE as well as other secondary outcomes including: all-cause mortality, urinary tract occurrences, sepsis, wound occurrences, cardiac and respiratory adverse events. These are important findings since preoperative glucocorticoid use is a modifiable factor., (Copyright © 2015 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.)

Thalassemia continues to be a major health burden. The chronicity of the disease and the high cost of life-long treatment make prevention strategies crucial in the management of this disease. In this article, we revisit different successful prevention strategies, and underline the Lebanese model. The Chronic Care Center (CCC), Beirut, is the only specialized center in Lebanon for the treatment and prevention of thalassemia. The current number of patients registered up to August 2013 was 724, representing cases from all over Lebanon. In 1994, the center launched a national prevention program following the World Health Organization (WHO) recommendations. The major activities of the program include awareness campaigns, screening for thalassemia carriers in the general population and high risk groups, registry of new cases and follow-up on the mandatory premarital law (established at the same time). Screening programs showed a carrier rate of around 2.3% in the general population, and 4.0-41.0% in high risk groups. The major pitfall in the law is that only persons with a mean corpuscular volume (MCV) of >70.0 fL are asked to perform further hemoglobin (Hb) testing. A significant decrease in the number of new cases of thalassemia patients in Lebanon reflects the efforts deployed in the prevention of the disease. However, some limitations are faced in reaching a complete eradication of the disease, mainly due to the fact that abortion is illegal and due to pitfalls and incorrect implementation of the premarital law.

The term Nontransfusion dependent thalassaemia (NTDT) was suggested to describe patients who had clinical manifestations that are too severe to be termed minor yet too mild to be termed major. Those patients are not entirely dependent on transfusions for survival. If left untreated, three main factors are responsible for the clinical sequelae of NTDT: ineffective erythropoiesis, chronic hemolytic anemia, and iron overload. Reactive oxygen species (ROS) generation in NTDT patients is caused by 2 major mechanisms. The first one is chronic hypoxia resulting from chronic anemia and ineffective erythropoiesis leading to mitochondrial damage and the second is iron overload also due to chronic anemia and tissue hypoxia leading to increase intestinal iron absorption in thalassemic patients. Oxidative damage by reactive oxygen species (generated by free globin chains and labile plasma iron) is believed to be one of the main contributors to cell injury, tissue damage, and hypercoagulability in patients with thalassemia. Independently increased ROS has been linked to a myriad of pathological outcomes such as leg ulcers, decreased wound healing, pulmonary hypertension, silent brain infarcts, and increased thrombosis to count a few. Interestingly many of those complications overlap with those found in NTDT patients.

The East Lau Spreading Center (ELSC) and Valu Fa Ridge (VFR) comprise a ridge segment in the southwest Pacific Ocean where rapid transitions in the underlying mantle chemistry manifest themselves as gradients in seafloor rock geochemistry. We studied the geology and microbial diversity of three silicate rock samples and three inactive sulfide chimney samples collected, from north to south, at the vent fields Kilo Moana, ABE, Tui Malila, and Mariner. This is the first study of microbial populations on basaltic andesite, which was sampled at Mariner vent field. Silicate rock geochemistry exhibits clear latitudinal trends that are mirrored by changes in bacterial community composition. α-proteobacteria, ε-proteobacteria, and Bacteroidetes are most common on a silicate collected from Kilo Moana and their proportions decrease linearly on silicates collected further south. Conversely, a silicate from Mariner vent field hosts high proportions of a unique lineage of Chloroflexi unrelated (<90% sequence similarity) to previously recovered environmental clones or isolates, which decrease at ABE and are absent at Kilo Moana. The exteriors of inactive sulfide structures are dominated by lineages of sulfur oxidizing α-proteobacteria, γ-proteobacteria, and ε-proteobacteria, while the interior of one chimney is dominated by putative sulfur-reducing δ-proteobacteria. A comparison of bacterial communities on inactive sulfides from this and previous studies reveals the presence of a clade of uncultured Bacteroidetes exclusive to sulfidic environments, and a high degree of heterogeneity in bacterial community composition from one sulfide structure to another. In light of the heterogeneous nature of bacterial communities observed here and in previous studies of both active and inactive hydrothermal sulfide structures, the presence of numerous niches may be detected on these structures in the future by finer scale sampling and analysis.

Respiratory mechanics were studied in nine intubated dogs before and after exposure to aerosolized papain under conditions known to produce emphysemalike lesions. Forced oscillatory resistance (RFO), compliance (CFO), and inertance (IFO) were computed from impedance data obtained at transrespiratory pressures of -10, 0 (FRC), +10, and +20 cmHWO. Dynamic compliance during tidal breathing (CTB) was also measured at FRC. After papain exposure CTB and CFO increased by 25% (P less than 0.05) at FRC and at +10 cmH2O. There were no consistent changes in RFO or IFO at FRC. However, RFO showed a greater dependency on transrespiratory pressure, which suggests that the elastic properties of airways may also have been affected by papain. Measurements made in open-chested papain-exposed animals showed that about 17% of total RFO and 20% of total elastance were attributable to the chest wall. Forced oscillatory impedance data are sensitive to experimental changes in lung mechanics and provide useful estimates of standard respiratory parameters.