Diatom-guided bone healing via a hybrid natural scaffold.

Bone tissue engineering (BTE) involves the design of three-dimensional (3D) scaffolds that aim to address current challenges of bone defect healing, such as limited donor availability, disease transmission risks, and the necessity for multiple invasive surgeries. Scaffolds can mimic natural bone structure to accelerate the mechanisms involved in the healing process. Herein, a crosslinked combination of biopolymers, including gelatin (GEL), chitosan (CS), and hyaluronic acid (HA), loaded with diatom (Di) and ß-sitosterol (BS), is used to produce GCH-Di-S scaffold by freeze-drying method. The GCH scaffold possesses a uniform structure, is biodegradable and biocompatible, and exhibits high porosity and interconnected pores, all required for effective bone repair. The incorporation of Di within the scaffold contributes to the adjustment of porosity and degradation, as well as effectively enhancing the mechanical property and biomineralization. In vivo studies have confirmed the safety of the scaffold and its potential to stimulate the creation of new bone tissue. This is achieved by providing an osteoconductive platform for cell attachment, prompting calcification, and augmenting the proliferation of osteoblasts, which further contributes to angiogenesis and anti-inflammatory effects of BS.

Nanostructured multifunctional stimuli-responsive glycopolypeptide-based copolymers for biomedical applications.

Inspired by natural resources, such as peptides and carbohydrates, glycopolypeptide biopolymer has recently emerged as a new form of biopolymer being recruited in various biomedical applications. Glycopolypeptides with well-defined secondary structures and pendant glycosides on the polypeptide backbone have sparked lots of research interest and they have an innate ability to self-assemble in diverse structures. The nanostructures of glycopolypeptides have also opened up new perspectives in biomedical applications due to their stable three-dimensional structures, high drug loading efficiency, excellent biocompatibility, and biodegradability. Although the development of glycopolypeptide-based nanocarriers is well-studied, their clinical translation is still limited. The present review highlights the preparation and characterization strategies related to glycopolypeptides-based copolymers, followed by a comprehensive discussion on their biomedical applications with a specific focus on drug delivery by various stimuli-responsive (e.g., pH, redox, conduction, and sugar) nanostructures, as well as their beneficial usage in diagnosis and regenerative medicine.

Comparison of in-hospital mortality of COVID-19 between pregnant and non-pregnant women infected with SARS-CoV-2: a historical cohort study.

OBJECTIVES: This study aimed to compare pregnant and non-pregnant women infected with SARS-CoV-2 disease (COVID-19) in terms of in-hospital mortality. METHODS: This historical cohort study was conducted on hospitalized women of reproductive ages (15-49 years) infected with SARS-CoV-2 in Fars province, Iran during 15 March 2019-10 May 2021. RESULTS: Out of the 5,322 patients, 330 were pregnant. The fatality rate of SARS-CoV-2 was 1.2% amongst pregnant women and 3.5% amongst non-pregnant ones. Pregnant and non-pregnant women reported the same history of smoking, opium use, previous COVID-19 infection, vaccination against SARS-CoV-2, and COVID-19 symptoms (p>0.05 for all). However, the pregnant women were younger and had fewer underlying diseases (p<0.001 for both). The results revealed no significant difference between the two groups regarding in-hospital clinical manifestations including the number of days after the onset of COVID-19 symptoms, mechanical ventilation, and long involvement (cRR; 95% CI=0.99 (0.96-1.02), 1.18 (0.72-2.02), and 0.95 (0.88-1.02), respectively). Nonetheless, Intensive Care Unit (ICU) admission was significantly higher in pregnant women (cRR; 95% CI=2.37(1.85-3.02)). After adjusting for age, history of underlying diseases, and ICU admission, pregnant women showed lower in-hospital mortality due to COVID-19 compared to non-pregnant women (aRR; 95% CI=0.32 (0.12-0.87)). CONCLUSIONS: Based on the current study findings, pregnant women showed lower in-hospital mortality due to COVID-19 compared to non-pregnant ones. Nevertheless, they should follow the same recommendations as non-pregnant women, avoiding exposure to the virus and receiving medical treatment and vaccination. Further studies are recommended to address the follow-up of recovered pregnant women, their babies, and puerperium.

Quality of Life and Its Determinants in Liver Transplantation Candidates: A Missed Link in Liver Care Program during the Waiting Time for Liver Transplantation.

Background: The health-related quality of life (HRQOL) in the before liver transplantation (LT) stage has not been studied as much as that after the LT stage. We aimed to assess HRQOL and its determinants before the LT stage. Methods: As a cross-sectional study, HRQOL of all adult patients (n=632) referred to the LT center of Shiraz, Iran in 2018-2019 were assessed. Demographic, socioeconomic, medical, and paraclinical data were requested. Physical (PCS) and mental (MCS) aspects of HRQOL were assessed using the SF36 questionnaire. Univariable, multivariable (linear regression), and confirmatory factor analysis were performed utilizing SPSS 20 and Mplus 6.1 software. P<0.05 was considered to be significant. Results: The mean age of the patients was 47.6±12.3 years, while 414 (65.6%) were men, and the mean, score of the model for end-stage liver disease (MELD) was 18.36±5.58. The mean score of QOL, PCS, and MCS was 50.01±21.73, 46.23±23.23, and 53.78±23.91 (out of 100), respectively. Vitality had the most association with HRQOL, while role limitations had the lowest. The multivariable analysis revealed that unemployment (P<0.001), anemia (P=0.005), weight loss (P=0.005), diabetes mellitus (DM) (P=0.009), low MELD score (P=0.027), and drug use (P=0.03) were the significant determinants of HRQOL, respectively. Conclusion: The present study showed that HRQOL in the LT candidates was at the intermediate level, while their PCS and MCS are at the low and moderate levels, respectively. Furthermore, physical performance, job status, anemia, weight loss, MELD score, DM, and drug use should be considered as the significant determinants of HRQOL in the LT candidates.

Assessing the measurement invariance of the RCADS-25 questionnaire across gender and child-parent dyads in the presence of multilevel data.

PURPOSE: This study aims to assess the measurement invariance of the short version of the Revised Child Anxiety and Depression Scale (RCADS-25) across male and female adolescents along with child self-reports and parent proxy-reports. METHODS: The sample consisted of 2039 adolescents and their parents from 51 public and private schools in Shiraz (southern Iran). The measurement invariance of the RCADS-25 was investigated by the multilevel multiple-indicators multiple-causes model. In addition, the reliability of the questionnaire was examined by Cronbach's alpha coefficient, and its validity was evaluated by exploratory and categorical confirmatory factor analysis. RESULTS: Although the RCADS-25 includes five (20%) non-invariant items across male and female adolescents, their impact is negligible at the scale level. In addition, 10 out of 25 items (40%) were non-invariant across self- and proxy-reports, which did not have substantial effect at the scale level. CONCLUSION: Based on our findings, the instrument can be used, albeit with caution, for comparing depression and anxiety scores between male and female adolescents as well as child self-reports and parent proxy-reports.