Low Weight Research Articles

Renal endowment in men and women: start from the beginning

The development of the human kidney leads to the establishment of nephron endowment through a process influenced by both genetic and environmental factors. There is individual variability regarding nephron endowment and factors including aging and pathological conditions contribute to the decline in the number of nephrons, impacting renal function. Genetic determinants, such as mutations in crucial developmental genes like Pax2, and epigenetic mechanisms mediated by key enzymes including sirtuin 3, play critical roles in the regulation of the number of nephrons, with implications for kidney disease susceptibility. Sexual dimorphism significantly influences kidney development and function, with the number of nephrons being significantly lower in females, consistent with lower female birth weight, which is considered a surrogate for nephron endowment. Also, although females have fewer nephrons, they experience a slower decline in GFR compared to males. Gender disparity in chronic kidney disease progression has been attributed to factors such as metabolism, oxidative stress, renal hemodynamics, and sex hormones. Understanding the complexities of nephron endowment variability, genetic determinants, and sexual dimorphism in kidney development and function is crucial for elucidating the mechanisms underlying individual kidney disease susceptibility and progression. Further research in this field holds promise for the development of personalized approaches to kidney disease prevention, management, and treatment.

Establishment of a mouse model of ovarian oxidative stress induced by hydrogen peroxide

IntroductionOxidative stress, resulting from environmental changes, significantly affects female fertility. Developing a mouse model to study oxidative stress lays the groundwork for research into human reproductive health and livestock fertility.Materials and methodsIn this study, we established and evaluated an oxidative stress model by administering hydrogen peroxide (H2O2) to mice. ICR mice of similar age (7–8 weeks old) and average body weight (31.58 ± 1.12 g) were randomly assigned to four groups (A, B, C, and D). Group A served as the control and was injected with a saline solution, while groups B, C, and D received saline solutions containing 0.75%, 1.50%, and 3.0% H2O2, respectively, over one week. We measured the body weights of all mice before and after the experimental period.Results and discussionOur findings showed that the average body weight of mice in groups A and B increased, while groups C and D experienced weight loss. Group C showed a significantly lower average weight gain compared to groups A and B, and group D exhibited an even more pronounced reduction in weight gain. Although group D had a high mortality rate, there was no significant difference in mortality rates among groups B, C, and D. Serum malondialdehyde (MDA) content increased with higher concentrations of H2O2, with a significant difference noted between groups C and A. Catalase (CAT) activity in group B was significantly higher than in group A, while superoxide dismutase (SOD) activity in group C was notably elevated compared to groups A and B. Conversely, glutathione peroxidase (GSH-Px) activity in group C was significantly lower than in both group A and group B. Hematoxylin and eosin (HE) staining revealed changes in ovarian morphology and follicle dynamics. The percentage of atretic follicles in group C was significantly higher than in the control group, and group D had a significantly lower total number of healthy follicles compared to the untreated group. Increased H2O2 content resulted in a reduction of ovary size and an irregular appearance in group D.ConclusionBased on our findings, treatment with 1.50% H2O2 effectively established an oxidative stress model in mice within 1 week. This model serves as a valuable reference for future clinical studies on oxidative stress and reproductive disorders in female animals and humans.

Association of maternal 25(OH)D levels during pregnancy with fetal birth weight and preschooler growth status: A retrospective birth cohort study.

There is limited and conflicting evidence available regarding the correlation between maternal vitamin D status and childhood overweight and body mass index (BMI). The aim of this study was to investigate the following: (1) potential association between maternal 25-hydroxyvitamin D (25(OH)D) levels and newborn growth status; (2) relationship between maternal 25OHD levels and BMI and the risk of overweight with preschoolers being overweight. A cohort of 3213 eligible singleton mother-infant pairs were used to investigate the possible associations between maternal 25(OH)D levels and fetal growth status. Data of 1767 available singleton mother-infant pairs and 6-year-old preschoolers was applied to analyze the potential correlations between maternal 25(OH)D status and risk of childhood overweight. Compared with sufficient 25(OH)D in pregnancy group (≥75 nmol/L), there were no correlations between the maternal 25(OH)D deficiency (<50 nmol/L) and large gestational age (LGA) (p = 0.465), small gestational age (SGA) (p = 0.607), lower birth weight (LBW) (p = 0.725) or fetal macrosomia (p = 0.535). Moreover, no significant associations between insufficient maternal 25(OH)D (50-75 nmol/L) and LGA (p = 0.505), SGA (p = 0.816), LBW (p = 0.816), or fetal macrosomia (p = 0.413) were observed. We found statistically significant disparities between the fetal birth weight and height (p < 0.001), weight (p < 0.001), head circumference (p = 0.001) of 6-years preschooler. No significant associations were found between the maternal 25(OH)D levels and BMI and risk of overweight at 6-year-old preschoolers. There were no apparent correlation found between maternal 25(OH)D concentrations and fetal birth status. There was no evidence found to suggest the effect of maternal 25(OH)D level on overweight at 6-year-old preschoolers.

Spatial Variability in the Speciation of Lead (Pb) and Other Metals Across Urban Lawns Is Linked to Post-Deposition Weathering Reactions

The historical use of lead (Pb) poses ongoing health risks via exposure to contaminated urban soils. However, there is limited information about heterogeneity in Pb speciation and distribution at the house lot scale. This study determined highly spatially resolved Pb and other metal speciation along horizontal transects and vertical soil cores from three homes in the Akron, Ohio (USA) municipal. Solid phase characterization was coupled with a sequential extraction protocol to determine operationally defined speciation (exchangeable (MEX), reducible (MRED), oxidizable (MOX), and residual (MRES)). Lead and Zn were strongly correlated across all fractions (R2 = 0.92). Total extractable Pb and Zn were found in low weight percent concentrations nearest to the homes, and speciation was dominated by MEX and MRED. High Pb in the MEX fraction was correlated with the presence of Pb-bearing paint chips in the soil. Lead in the MEX fraction in soils near the homes decreased with increasing time due to exterior renovations coupled with increases in Pb and Zn in the MRED fraction. These results suggest that homes are the dominant source of Pb and Zn due to the weathering of exterior surfaces and highlight the acute risk of exposure to more labile Pb immediately following exterior renovations and damage to home exteriors in areas of older housing stock.

Subcutaneous emphysema in patients undergoing robotic cardiac surgery: risk factors and clinical outcome.

Little is known about the incidence of subcutaneous emphysema (SE) after robotic cardiac surgery. The aim of this study was to describe the incidence, identify risk factors, and assess its influence on postoperative outcomes. Patients undergoing robotic mitral valve repair (n = 63, 54.3%), robotic minimally invasive direct coronary artery bypass grafting (n = 23, 19.8%), and robotic totally endoscopic coronary artery bypass grafting (n = 30,25.9%) were included in the analysis (total n = 116). Subcutaneous emphysema occurred in 53/116 patients (45.7%). It was mild in 30/53 patients (56.6%), moderate in one patient (1.9%), and severe in 22/53 patients (41.5%). Low body weight (p = 0.009), low BMI (p = 0.006), small body surface area (p = 0.01), and older age (p = 0.041) significantly correlated with SE. Patients undergoing robotic mitral valve repair were affected more often than patients undergoing robotic coronary artery bypass grafting (p = 0.04). Severe subcutaneous emphysema resulted in an increased need for CT-chest imaging (p = 0.026), and additional chest tubes (p = 0.029). Severe emphysema was highly associated with pneumothorax (p < 0.001) and increased duration of chest tube drainage (p = 0.003). Subcutaneous emphysema after robotic heart surgery occurs preferentially in patients with low body weight, low BMI, a small body surface area, and older age and is more common in robotic MVR than in robotic coronary artery bypass surgery. It leads to an increased need for thoracic imaging and additional chest tube insertion. Clinical outcomes are not affected.

The evaluation of endotracheal tube cuff pressure in pediatric patients by subjective inflation techniques: a prospective observational study.

Cuffed endotracheal tubes (ETTs) are commonly used in pediatric patients, with the gold standard for measuring cuff pressure being a cuff pressure manometer. However, this equipment is not always available in every operating room. Subjective inflation techniques, such as the minimal occluding volume (MOV) technique and the stethoscope-guided (Steth) technique, offer convenient and safe alternatives to standard methods but do not provide quantitative measurements. This study aimed to evaluate ETT cuff pressures and volumes of air inflated using the two subjective techniques (MOV and Steth) in pediatric patients. This prospective observational study was conducted at the Department of Anesthesiology, Faculty of Medicine, Khon Kaen University, Thailand. We included healthy pediatric patients aged 2 to 7 years undergoing elective surgeries under general anesthesia with a cuffed ETT. The primary objective of this study was to compare the mean ETT cuff pressures and volumes of air inflated using the two subjective inflation techniques (MOV and Steth method). The secondary objectives include identifying factors associated with inappropriate inflation and evaluating post-intubation complications. Sixty-four pediatric patients were analyzed. The overall mean ETT cuff pressure was 26.52 ± 8.68 cmH2O. The target was achieved in 46.88% of patients, with overinflation in 32.81% and underinflation in 20.31%. The mean ETT cuff pressure in the MOV group was 27.77 ± 8.89 cmH2O and in the Steth group was 25.33 ± 8.34 cmH2O, with a non-significant mean difference of 2.44 cmH2O (95% CI [-1.89, 6.77], p = 0.264). The mean volume of air inflated in the MOV group was 0.78 ± 0.25ml, and in the Steth group was 0.68 ± 0.22ml, with a non-significant mean difference of 0.10ml (95% CI [-0.01, 0.22], p = 0.084). Younger age, lower weight, and shorter height were significantly associated with an increased risk of overinflation. An ETT size with an internal diameter (ID) of 5mm was significantly associated with an increased risk of underinflation. No post-intubation complications were reported. Subjective inflation techniques (MOV or Steth) achieve target ETT cuff pressures in less than 50%, and carry the risks of both overinflation and underinflation,even without post-intubation complications. TCTR20211016001 (registered with the Thai Clinical Trials Registry on October 16, 2021).

Biomarkers to Differentiate Acute Chest Syndrome From Vaso-Occlusive Crisis in Children With Sickle Cell Disease.

Acute Chest Syndrome (ACS) is the leading cause of death in children with sickle cell disease (SCD) in the US-about half of the children who develop ACS present initially with pain. Here, we studied biomarkers to differentiate ACS from vaso-occlusive crises (VOC) in children with SCD who presented with pain to the emergency department (ED). We conducted a prospective cohort study of consecutive patients who presented to the ED with pain and were discharged with ACS or VOC between March, 2017 and February, 2020. We identified 7 patients with ACS and 19 patients with VOC. The two groups were comparable in age and sex. All patients with ACS had asthma versus 42% of the VOC group. The ACS group had lower weight and BMI z-scores. Patients with ACS compared to VOC had significantly higher respiratory rates, lower O2 saturation, and longer hospital stays. They also had higher white blood cell count, glucose level (> 99 mg/dL), anion gap (> 9 mEq/L), sPLA2 (> 7 pg/mL), IFN-γ (> 17.8 pg/mL), IL-10 (1.54 pg/mL), and IL-12 (> 0.5 pg/mL) levels. We identified biomarkers associated with ACS development in children with SCD presenting with pain that allow for earlier ACS interventions to reduce mortality and morbidity.

Wood and Wood-Based Materials in Space Applications—A Literature Review of Use Cases, Challenges and Potential

Current political and sociological efforts to respond to the need for more environmentally friendly technologies have inspired a revival of wood and wood-based material utilization in space systems. The popularity of these materials has faded since their widespread use in the early days of aerospace engineering. This work reviews the literature to provide an overview of use cases, the motivation for using wood and wood-based materials and the challenges involved. A small number of applications were identified in which wood and wood-based materials were preferred over non-renewable raw materials. They are mainly applied for less-stressed disposable components or as a thermal protection material. It can be shown that the applied wooden materials have advantages such as low production costs, easy availability, easy and environment-friendly decomposition and low weight. However, only a limited number of applications have achieved a high level of technological readiness so far. Properties such as anisotropy and a lack of uniformity, defects in wood, the quantity available material and a lack of standards for the certification of wooden materials represent challenges. These are addressed in the current research, which additionally focuses on sustainable growth, enhanced environmental friendliness and advanced lightweight design.

Maternal Dietary Improvement or Leptin Supplementation During Suckling Mitigates the Long-Term Impact of Maternal Obesogenic Conditions on Inflammatory and Oxidative Stress Biomarkers in the Offspring of Diet-Induced Obese Rats

This study investigates the impact of maternal nutrition during lactation on inflammation and oxidative stress in the offspring of diet-induced obese rats, along with the potential benefits of leptin supplementation during suckling. Dams were fed either a standard diet (SD), a western diet (WD) before and during gestation and lactation (WD-dams), or a WD switched to an SD during lactation (Rev-dams). Offspring were supplemented with leptin or vehicle during suckling and then fed an SD or WD until four months. Offspring of the Rev-dams exhibited improved metabolic indicators, including lower body weight, reduced plasma levels of TNF-alpha, a higher adiponectin/leptin (A/L) ratio, enhanced liver antioxidant defenses, and decreased inflammation markers in white adipose tissue (WAT) compared to WD-dams, with sex differences. Leptin supplementation further modulated these markers, reducing oxidative stress in liver and inflammation in WAT and liver (e.g., hepatic Tnfa expression decreased by 45% (males) and 41% (females) in the WD group on an SD), and improving the A/L ratio, with effects varying by maternal conditions and sex. In conclusion, this study underscores the importance of maternal nutrition and leptin intake during suckling in shaping long-term metabolic and inflammatory health in offspring, offering strategies to mitigate the adverse effects of maternal obesity on future generations.

In-hospital bioimpedance-derived total body water predicts short-term cardiovascular mortality and re-hospitalizations in acute decompensated heart failure patients.

Hospital re-admissions in heart failure (HF) patients are mostly caused by an acute exacerbation of their chronic congestion. Bioimpedance analysis (BIA) has emerged as a promising non-invasive method to assess the volume status in HF. However, its correlation with clinically assessed volume status and its prognostic value in the acute intra-hospital setting remains uncertain. In this single-center observational study, patients (n = 49) admitted to the cardiology ward for acute decompensated HF (ADHF) underwent a daily BIA-derived volume status assessment. Median hospital stay was 7 (4-10) days. Twenty patients (40%) reached the composite endpoint of cardiovascular mortality or re-hospitalization for HF over 6months. Patients at discharge displayed improved NYHA class, lower body weight, plasma and blood volume, as well as lower NT-proBNP levels compared to the admission. Compared to patients with total body water (TBW) less than or equal to that predicted by body weight, those with higher relative TBW levels had elevated NT-proBNP and E/e´ (both p < 0.05) at discharge. In the Cox multivariate regression analysis, the BIA-derived delta TBW between admission and discharge showed a 23% risk reduction for each unit increase (HR = 0.776; CI 0.67-0.89; p = 0.0006). In line with this finding, TBW at admission had the highest prediction importance of the combined endpoint for a subgroup of high-risk HF patients (n = 35) in a neural network analysis. In ADHF patients, BIA-derived TBW is associated with the increased risk of HF hospitalization or cardiovascular death over 6months. The role of BIA for prognostic stratification merits further investigation.

The Incidence and Predictive Factors of Thromboembolism During Hospitalizations for Inflammatory Bowel Disease Flare-Ups: A Retrospective Cohort Study in Taiwan.

Thromboembolism (TE) notably increase morbidity and mortality among inflammatory bowel disease (IBD) patients. Despite ECCO's 2024 guidelines advocating routine anticoagulant prophylaxis, its application in Asia remains inconsistent due to a lack of regional studies. This research investigates the incidence and predictors of TE during IBD-related hospitalizations in Taiwan, aiming to improve prevention strategies. Our retrospective cohort study included 282 adult IBD patients, accounting for 515 flare-up related hospitalizations at Linkou Chang Gung Memorial Hospital from January 2001 to March 2024. Patients were classified into two groups based on the occurrence of TE. The incidence of TE was 1.55%. The TE group had significantly lower body weight, body mass index (BMI), hemoglobin and albumin levels but higher rate of sepsis and concurrent autoimmune diseases compared to the non-TE group. Multivariate analysis indicated that concurrent autoimmune diseases and hypoalbuminemia were independent predictors of TE. The optimal serum albumin cutoff was established at 3.01 g/dL, with sensitivities and specificities of 87.5% and 77.3%, respectively. This pioneering Asian study identifies concurrent autoimmune diseases and low serum albumin as key predictors of TE in hospitalized IBD patients. We recommend targeted anticoagulant prophylaxis for IBD patients with these risk factors, especially when serum albumin falls below 3.01 g/dL.

Performance and Degradation Analysis of Low and High Equivalent Weight Short Side Chain PFSA Membranes in PEMFCs

Performance and Degradation Analysis of Low and High Equivalent Weight Short Side Chain PFSA Membranes in PEMFCs

Single laser based novel wavelength shift keying scheme for ground to satellite bidirectional links

Abstract Laser communication in space is gaining more recognition due to its ability to provide a much broader and unregulated data transmission capacity compared to traditional radio frequency systems, while also significantly decreasing the size, power requirements, and weight of the communication system. In this work, a novel technique for the generation of a wavelength shift keying (WSK) signal for the bidirectional transmission of 10 Gbps data between the ground station and low Earth orbit (LEO) satellite is presented. Our proposed scheme requires a single laser source to transmit WSK signal, that generally requires two wavelength sources to transmit the binary data bits. Furthermore, the scheme allows us to remodulate the optical signal received at the LEO satellite for downlink signal transmission. Therefore, the requirement of a laser source at the LEO satellite is eliminated, achieving the much desirable goals of low power consumption, weight and cost. The free space optical (FSO) channel is modelled using the gamma-gamma channel model. The performance of the proposed link is also compared with a conventional On-Off keying (OOK) based modulation scheme by using bit-error-rate (BER) as the performance metric.

PTPRK regulates glycolysis and de novo lipogenesis to promote hepatocyte metabolic reprogramming in obesity

Fat accumulation, de novo lipogenesis, and glycolysis are key drivers of hepatocyte reprogramming and the consequent metabolic dysfunction-associated steatotic liver disease (MASLD). Here we report that obesity leads to dysregulated expression of hepatic protein-tyrosine phosphatases (PTPs). PTPRK was found to be increased in steatotic hepatocytes in both humans and mice, and correlates positively with PPARγ-induced lipogenic signaling. High-fat-fed PTPRK knockout male and female mice have lower weight gain and reduced hepatic fat accumulation. Phosphoproteomic analysis in primary hepatocytes and hepatic metabolomics identified fructose-1,6-bisphosphatase 1 and glycolysis as PTPRK targets in metabolic reprogramming. Mechanistically, PTPRK-induced glycolysis enhances PPARγ and lipogenesis in hepatocytes. Silencing PTPRK in liver cancer cell lines reduces colony-forming capacity and high-fat-fed PTPRK knockout mice exposed to a hepatic carcinogen develop smaller tumours. Our study defines the role of PTPRK in the regulation of hepatic glycolysis, lipid metabolism, and tumour development in obesity.

Associations of nutrition education with diet quality indexes and chronotype: a cross-sectional study

ABSTRACT This study examined the impact of nutrition education on chronotype, sleep quality, and dietary quality among university students. Participants included 317 students with nutrition education and 280 without. Data were collected through questionnaires assessing demographic characteristics, chronotype (using the Morning-Evening Questionnaire), sleep quality (via the Pittsburgh Sleep Quality Index), and dietary habits. Anthropometric measurements and 24-hour food recalls were also recorded. Dietary quality was evaluated using the Healthy Eating Index (HEI)-2020, while dietary fat and carbohydrate quality were assessed with the Fat Quality Index (FQI) and Carbohydrate Quality Index (CQI), respectively. Results indicated that students who received nutrition education had significantly lower body weight, height, and waist circumference compared to those without. Of the students, 8.9% had a morning, 7% had an evening and the rest had an intermediate chronotype. HEI-2020, CQI, and FQI scores were significantly higher in the nutrition education group. Although no significant relationship was found between nutrition education and chronotype, improved dietary and sleep quality were observed in the group with education. This suggested that enhancing nutritional knowledge can positively impact health by improving dietary quality and sleep.

Investigation of Prognosis and Related Factors of Premature Neonates

The birth of premature infants remains a challenge in many societies. This cross-sectional study investigates prenatal care and influential factors in preterm infants hospitalized in the Neonatal Intensive Care Unit (NICU) of Fatemieh Educational-Medical Center in Hamadan, Iran, from March 2018 to March 2019. We examined premature infants with a gestational age of less than 37 weeks who were admitted to the NICU. Data on demographic and maternal characteristics, length of hospital stay, maternal underlying diseases, probable causes of preterm birth, neonatal complications, treatment types, treatment-related complications, resuscitation needs, ventilation, and mortality rates were extracted from patient records. Among 388 preterm infants studied, 204 (52.6%) were female. The mean gestational age was 31.8±2.8 weeks, birth weight was 1647.4±625.6 grams, and average hospital stay was 10.2±9.3 days. The most common maternal underlying disease was pregnancy-induced hypertension or preeclampsia (22.2%), respiratory distress syndrome, jaundice, and low birth weight were the leading reasons for hospitalization (84%). Neonatal outcomes included 92 (23.7%) deaths, 25 (6.4%) intraventricular hemorrhages, 39 (10.1%) patent ductus arteriosus cases, 20 (5.2%) bronchopulmonary dysplasia cases, and 41 (10.6%) retinopathy of prematurity cases. Regression analysis revealed significant predictors of neonatal mortality, including male gender, maternal underlying diseases, need for cardiopulmonary resuscitation, low Apgar score at one-minute, lower birth weight, shorter gestational age, and NICU stay duration. This study underscores the high neonatal mortality rate among preterm infants. Implementing preventive measures, particularly addressing maternal underlying diseases and low birth weight, can significantly reduce neonatal mortality.

Application of Sound Waves During the Curing of an Acrylic Resin and Its Composites Based on Short Carbon Fibers and Carbon Nanofibers

Research into particulate polymer composites is of significant interest due to their potential for enhancing material properties, such as strength, thermal stability, and conductivity while maintaining low weight and cost. Among the various techniques for preparing particle-based composites, ultrasonic wave stimulation is one of the principal laboratory-scale methods for enhancing the dispersion of the discontinuous phase. Nevertheless, there is a scarcity of empirical evidence to substantiate the impact of stimulating materials with natural sound frequencies within the acoustic spectrum, ranging from 20 Hz to 20 kHz, during their formation process. The present work investigates the effect of acoustic stimuli with frequencies of 56, 111, and 180 Hz on the properties of an acrylic-based polymer and its discontinuous carbon-based composites. The results indicated that the stimulus frequency affects the cure time of the studied systems, with a notable reduction of 31% and 21% in the cure times of the neat polymer and carbon-nanofiber-based composites, respectively, after applying a frequency of 180 Hz. Additionally, the higher stimulation frequencies reduced porosity in the samples, increased the degree of dispersion of the discontinuous phase, and altered the composite materials’ thermal, optical, and electrical behavior.

A new Rose Bengal glycopolymer: Photosensitization in two stages

Antimicrobial photodynamic therapy is a promising alternative to deal with antimicrobial resistance. However, both the low specificity and low local oxygen molecular concentrations decrease the antimicrobial efficiency limiting its use. An interesting approach to the problem is the use of molecules that can react reversibly with singlet oxygen by the formation of reversible endoperoxides, such as naphthalene, anthracene and pyridone derivatives. Particularly, the use of these molecules with mannosyl derivatives allow the interaction with adhesins presented on pili and fimbriae improving the localization near to bacteria. In this work, we synthesized polymeric nanoparticles able to generate singlet oxygen (under both irradiation and dark conditions) in the vicinity of a center capable of recognizing mannose and oxidize nearby biomolecules. Rose Bengal was used as photosensitizer due to its attractive photophysical properties (vis absorption, high singlet oxygen generation) and biocompatibility. The polymeric nanoparticles were obtained by radical polymerization using polyvinyl alcohol as a template, showing sizes around 300 nm with negative zeta potential by dynamic light scattering. The singlet oxygen generation was monitored following DPBF consumption and showed to be dependent on the amount of pyridone in the feed of polymers. In addition, the release of singlet oxygen was also dependent on pyridone concentration showing a slower rate constant at 40 % pyridone, while for contents of 10 % and 60 % higher rate constants were observed. The specific interaction of glycopolymers with Concanavalin A was demonstrated by successful agglutination assays, but also a low participation of unspecific interactions for polymers without mannosyl derivatives was observed. On the other hand, the oxidation of amino acids of Concanavalin A was monitored by acrylamide gel electrophoresis. Type I and Type II photosensitization were observed with the formation of dimers and fragments with lower molecular weight, while in dark conditions only products with lower molecular weight were observed, result consistent with singlet oxygen released by pyridone endoperoxides.

Honeycomb Molding - Forming Thermoplastic Sandwich Structures for Interior Applications

Trains play an important role in the sustainable mobility of the future. The changes in the market are reflected in the number of newly approved series by the German Federal Railway Authority (EBA); 226 new designs and redesigns of train cars were approved for use on German rails in 2019. Phenol-formaldehyde resins are used extensively specifically for railcar interiors. However, phenol-formaldehyde resins release carcinogenic vapors during and even after production if not completely sealed. As a result, European production standards and requirements have been increased, making the material less economical and increasingly difficult to enter the market. Further bans aimed at lower formaldehyde release limits are currently being considered by the European Union's Committee for Risk Assessment (RAC) and Committee for Socioeconomic Analysis (SEAC). In order to develop and design alternative materials, it is important to meet the requirements for stiffness, light weight, insulation and sustainability simultaneously. This research aim is therefore to develop a new class of material for interior components with improved stiffness, lower weight, lower CO2 footprint and no health hazards. The approach is to develop advanced composite sandwich panels that retain the ability to be molded into complex structures for interior applications. This is done through a thermoplastic honeycomb core structure that is manufactured directly from sheet material and fiber reinforced organo-sheets as the outer layers. The base matrix for all layers is kept uniform for better recyclability and consists of polycarbonate (PC) with sufficient flame retardant properties to provide an environmentally friendly alternative to existing phenolic resin and aramid epoxy honeycomb solutions while still complying with the security norms.

Highly selective split intein method for efficient separation and purification of recombinant therapeutic proteins from mammalian cell culture fluid

Biologics and vaccines have been successfully developed over the last few decades to treat many diseases. Each of these drugs must be highly purified for clinical use. Monoclonal antibodies (mAbs), the dominant therapeutic modality on the market, can be easily purified using the standard Protein A affinity platform. However, no generally applicable affinity platforms are available for the manufacture of other therapeutic proteins for clinical use. Thus, multicolumn chromatography processes for widely being used for product purification. These processes demand significant optimization to meet desired product quality attributes, where each step also decreases final yields. In this work, we demonstrate the novel self-removing iCapTagTM affinity tag, which provides a new platform for capturing, concentrating, and purifying recombinant proteins. Importantly, this system provides a tagless target protein, which is suitable for research and clinical use, where the only requirement for tag removal is a small change in buffer pH. No additional proteins, reagents or cofactors are required. We also present case studies demonstrating the use of iCapTagTM for highly efficient purification of untagged interferon alpha 2b, the ML39 single chain variable fragment (scFv), and the receptor binding domain (RBD) of SARS-CoV-2 spike protein. These proteins were expressed and secreted by Expi293 cells with the self-removing tag fused to their N-terminus. We were able to obtain highly pure (> 99%) tagless protein in a single purification step with high clearance of host cell DNA, tagged precursor, higher and lower molecular weight impurities. Based on these preliminary results, we propose the iCapTagTM as a universal capture platform for diverse classes of recombinant therapeutic proteins.