Evaluating the pro-survival potential of apoptotic bodies derived from 2D- and 3D- cultured adipose stem cells in ischaemic flaps.

In the realm of large-area trauma flap transplantation, averting ischaemic necrosis emerges as a pivotal concern. Several key mechanisms, including the promotion of angiogenesis, the inhibition of oxidative stress, the suppression of cell death, and the mitigation of inflammation, are crucial for enhancing skin flap survival. Apoptotic bodies (ABs), arising from cell apoptosis, have recently emerged as significant contributors to these functions. This study engineered three-dimensional (3D)-ABs using tissue-like mouse adipose-derived stem cells (mADSCs) cultured in a 3D environment to compare their superior biological effects against 2D-ABs in bolstering skin flap survival. The findings reveal that 3D-ABs (85.74 ± 4.51) % outperform 2D-ABs (76.48 ± 5.04) % in enhancing the survival rate of ischaemic skin flaps (60.45 ± 8.95) % (all p < 0.05). Mechanistically, they stimulated angiogenesis, mitigated oxidative stress, suppressed apoptosis, and facilitated the transition of macrophages from M1 to M2 polarization (all p < 0.05). A comparative analysis of microRNA (miRNA) profiles in 3D- and 2D-ABs identified several specific miRNAs (miR-423-5p-up, miR30b-5p-down, etc.) with pertinent roles. In summary, ABs derived from mADSCs cultured in a 3D spheroid-like arrangement exhibit heightened biological activity compared to those from 2D-cultured mADSCs and are more effective in promoting ischaemic skin flap survival. These effects are attributed to their influence on specific miRNAs.

Deep burn surgery of the whole dorsum of the hand: Composite skin grafting over acellular dermal matrix versus thick split-thickness skin grafting.

Preservation and restoration of hand function after burn injuries are challenging yet imperative. This study aimed to assess the curative effect of a composite skin graft over an acellular dermal matrix (ADM) and a thick split-thickness skin graft (STSG) for treating deep burns on the hand. Patients who met the inclusion criteria at the First Affiliated Hospital of Wenzhou Medical University between September 2011 and January 2020 were retrospectively identified from the operative register. We investigated patient characteristics, time from operation to the start of active motion exercise, take rates of skin graft 7 days post-surgery, donor site recovery, complications and days to complete healing. Patients were followed up for 12 months to evaluate scar quality using the Vancouver Scar Scale (VSS) and hand function through total active motion (TAM) and the Jebsen-Taylor Hand Function Test (JTHFT). A total of 38 patients (52 hands) who received thin STSG on top of the ADM or thick STSG were included. The location of the donor sites was significantly different between Group A (thick STSG) and Group B (thin STSG + ADM) (p = 0.03). There were no statistical differences in age, gender, underlying disease, cause of burn, burn area, dominant hand, patients with two hands operated on and time from burn to surgery between the two groups (p > 0.05). The time from operation to the start of active motion exercise, take rates of skin graft 7 days post-surgery and days to complete healing were not significantly different between Group A and Group B (p > 0.05). The rate of donor sites requiring skin grafting was lower in Group B than in Group A (22.2% vs. 100%, p < 0.001). There were no statistically significant differences in complications between the groups (p = 0.12). Moreover, 12 months postoperatively, the pliability subscore in the VSS was significantly lower in Group A than in Group B (p = 0.01). However, there were no statistically significant differences in vascularity (p = 0.42), pigmentation (p = 0.31) and height subscores (p = 0.13). The TAM and JTHFT results revealed no statistically significant differences between the two groups (p = 0.22 and 0.06, respectively). The ADM combined with thin STSG is a valuable approach for treating deep and extensive hand burns with low donor site morbidity. It has a good appearance and function in patients with hand burns, especially in patients with limited donor sites.

Nanobody in a Double "Y"-Shaped Assembly: A Promising Candidate for Lateral Flow Immunoassays.

Derived from camelid heavy-chain antibodies, nanobodies (Nbs) are the smallest natural antibodies and are an ideal tool in biological studies because of their simple structure, high yield, and low cost. Nbs possess significant potential for developing highly specific and user-friendly diagnostic assays. Despite offering considerable advantages in detection applications, knowledge is limited regarding the exclusive use of Nbs in lateral flow immunoassay (LFIA) detection. Herein, we present a novel double "Y" architecture, achieved by using the SpyTag/SpyCatcher and Im7/CL7 systems. The double "Y" assemblies exhibited a significantly higher affinity for their epitopes, as particularly evident in the reduced dissociation rate. An LFIA employing double "Y" assemblies was effectively used to detect the severe acute respiratory syndrome coronavirus-2 N protein, with a detection limit of at least 500 pg/mL. This study helps broaden the array of tools available for the development of Nb-based diagnostic techniques.

Apoptotic Bodies Derived from Fibroblast-Like Cells in Subcutaneous Connective Tissue Inhibit Ferroptosis in Ischaemic Flaps via the miR-339-5p/KEAP1/Nrf2 Axis.

Preventing and treating avascular necrosis at the distal end of the flaps are critical to surgery success, but current treatments are not ideal. A recent study shows that apoptotic bodies (ABs) generated near the site of apoptosis can be taken up and promote cell proliferation. The study reveals that ABs derived from fibroblast-like cells in the subcutaneous connective tissue (FSCT cells) of skin flaps promoted ischaemic flap survival. It is also found that ABs inhibited cell death and oxidative stress and promoted M1-to-M2 polarization in macrophages. Transcriptome sequencing and protein level testing demonstrated that ABs promoted ischaemic flap survival in endothelial cells and macrophages by inhibiting ferroptosis via the KEAP1-Nrf2 axis. Furthermore, microRNA (miR) sequencing data and in vitro and in vivo experiments demonstrated that ABs inhibited KEAP1 by delivering miR-339-5p to exert therapeutic effects. In conclusion, FSCT cell-derived ABs inhibited ferroptosis, promoted the macrophage M1-to-M2 transition via the miR-339-5p/KEAP1/Nrf2 axis and promoted ischaemic flap survival. These results provide a potential therapeutic strategy to promote ischaemic flap survival by administering ABs.

SARS-CoV-2 RdRp uses NDPs as a substrate and is able to incorporate NHC into RNA from diphosphate form molnupiravir.

The coronavirus disease 2019 has been ravaging throughout the world for three years and has severely impaired both human health and the economy. The causative agent, severe acute respiratory syndrome coronavirus 2 employs the viral RNA dependent RNA polymerase (RdRp) complex for genome replication and transcription, making RdRp an appealing target for antiviral drug development. Systematic characterization of RdRp will undoubtedly aid in the development of antiviral drugs targeting RdRp. Here, our research reveals that RdRp can recognize and utilize nucleoside diphosphates as a substrate to synthesize RNA with an efficiency of about two thirds of using nucleoside triphosphates as a substrate. Nucleoside diphosphates incorporation is also template-specific and has high fidelity. Moreover, RdRp can incorporate ß-d-N4-hydroxycytidine into RNA while using diphosphate form molnupiravir as a substrate. This incorporation results in genome mutation and virus death. It is also observed that diphosphate form molnupiravir is a better substrate for RdRp than the triphosphate form molnupiravir, presenting a new strategy for drug design.

Application of an infrared thermography-based model to detect pressure injuries: a prospective cohort study.

BACKGROUND: It is challenging to detect pressure injuries at an early stage of their development. OBJECTIVES: To assess the ability of an infrared thermography (IRT)-based model, constructed using a convolution neural network, to reliably detect pressure injuries. METHODS: A prospective cohort study compared validity in patients with pressure injury (n = 58) and without pressure injury (n = 205) using different methods. Each patient was followed up for 10 days. RESULTS: The optimal cut-off values of the IRT-based model were 0·53 for identifying tissue damage 1 day before visual detection of pressure injury and 0·88 for pressure injury detection on the day visual detection is possible. Kaplan-Meier curves and Cox proportional hazard regression model analysis showed that the risk of pressure injury increased 13-fold 1 day before visual detection with a cut-off value higher than 0·53 [hazard ratio (HR) 13·04, 95% confidence interval (CI) 6·32-26·91; P < 0·001]. The ability of the IRT-based model to detect pressure injuries [area under the receiver operating characteristic curve (AUC)lag 0 days , 0·98, 95% CI 0·95-1·00] was better than that of other methods. CONCLUSIONS: The IRT-based model is a useful and reliable method for clinical dermatologists and nurses to detect pressure injuries. It can objectively and accurately detect pressure injuries 1 day before visual detection and is therefore able to guide prevention earlier than would otherwise be possible. What is already known about this topic? Detection of pressure injuries at an early stage is challenging. Infrared thermography can be used for the physiological and anatomical evaluation of subcutaneous tissue abnormalities. A convolutional neural network is increasingly used in medical imaging analysis. What does this study add? The optimal cut-off values of the IRT-based model were 0·53 for identifying tissue damage 1 day before visual detection of pressure injury and 0·88 for pressure injury detection on the day visual detection is possible. Infrared thermography-based models can be used by clinical dermatologists and nurses to detect pressure injuries at an early stage objectively and accurately.

Application of infrared thermography in the early warning of pressure injury: A prospective observational study.

AIMS AND OBJECTIVES: To verify the ability of infrared thermography in objectively identifying pressure injury and its application value in the early warning of pressure injury. BACKGROUND: There is subjectivity in assessing the risk of pressure injury as well as diagnosis in clinical settings, which makes early detection and prevention difficult. DESIGN: Prospective, cohort study. METHOD: Four hundred and fifteen patients admitted to the adult intensive care units were enrolled by a convenience sampling method, and they received a follow-up monitoring for 10 days. The risk of pressure injury was assessed via Braden scale, and thermal images of sacral area were obtained by infrared thermal imager once a day. The predictive effects of infrared thermography and Braden scale on pressure injury were compared by the receiver operating characteristic curve from which the optimal cut-off value of skin temperature for predicting pressure injury was determined. The effect of skin temperature on pressure injury was described and compared, using Kaplan-Meier curve and Cox proportional hazard regression model, respectively. We followed STROBE checklist for reporting the study. RESULTS: The relative temperature of sacral area was negatively correlated with the risk of pressure injury. The efficiency of infrared thermography for diagnosing pressure injury was better than that of Braden scale. Based on the relative temperature optimal cut-off value (-0.1°C), Kaplan-Meier curve and Cox proportional hazard regression model analysis showed the incidence of pressure injury with relative temperature below -0.1°C was higher than the group with relative temperature above -0.1°C. CONCLUSIONS: Infrared thermography can objectively and accurately identify local hypothermia warnings of pressure injury before visual recognition. The application of infrared thermography into routine pressure injury risk assessment provides a timely and reliable method for nursing practitioners. RELEVANCE TO CLINICAL PRACTICE: Infrared thermography has great value of clinical application in daily pressure injury assessment. It is of great significance to make a faster and more objective clinical judgement for patients at risk of pressure injury.

Skin temperature and vascular attributes as early warning signs of pressure injury.

OBJECTIVES: This study aimed to validate the skin temperature on sacral region and vascular attributes as early warning signs of pressure injury. METHODS: Totally 415 patients admitted to the adult intensive care unit from August 2018 to April 2019 were prospectively screened. Daily blood pressure and blood glucose affecting vascular attributes and the relative skin temperature of sacral region were measured for 10 consecutive days. Collect the changes of these indicators during the occurrence of pressure injury. The optimal cut-off values of indicators were determined by X-tile analysis. The risk ratios of indicators associated with pressure injury were compared using the Cox proportional hazards regression model. RESULTS: There were no obvious interactions among blood pressure, blood glucose and relative skin temperature (P > 0.05). The optimal cutoff value for above indicators was 63.5 mmHg, 9.9 mmol/L and -0.1 °C, respectively. The incidence of pressure injury peaked on the 4th and 5th day after hospitalization when categorizing the patients into low- and high-risk groups according to the cutoff values (P < 0.05). Based on relative skin temperature, patients in the high-risk group were more likely to develop pressure injury (hazard ratio = 6.36, 95% confidence interval = 3.91, 10.36), when compared to the other two indicators of blood pressure and blood glucose. CONCLUSION: Stringent skin temperature and vascular attributes measurements were necessary for preventing pressure injury. Nursing measures should be taken according to warning sings to reduce the incidence of pressure injury.

[Endodontic-periodontal combined therapy for type â ¢ dens invaginatus in maxillary lateral incisor: a case report].

We report a clinical case of type Ⅲ dens invaginatus with endodontic-periodontal lesion in a maxillary lateral incisor. The palatal radicular anomaly predisposed the tooth to periodontal lesions. The caries along the palatal groove caused tooth pulp necrosis and periapical lesions. By means of microscopic root canal therapy, apical surgery, and guided periodontal tissue regeneration, the apical and periodontal infection were controlled, and the affected tooth was retained.

Use of dental operating microscope in non-surgical endodontic treatment / 口腔疾病防治

@#Dental operating microscope is recommended to complicated root canal therapy, for it could provide increased lighting and superior magnification, so that the survival rate of tooth is highly increased. More refined access of cavity preparation, canal cleaning, shaping and obturating are realized under microscope. This article combined literature reviews with the writers’ clinical experience, and it aims at helping clinicians to improve their ability to more accurately performance and minimally invasive endodontic procedures, such as locating hidden canals obstructed by calcifications, canals reduced in size, removing materials, reducing ledge formation, apical transportation, and repairing perforations.

The Starvation Resistance and Biofilm Formation of Enterococcus faecalis in Coexistence with Candida albicans, Streptococcus gordonii, Actinomyces viscosus, or Lactobacillus acidophilus.

INTRODUCTION: Enterococcus faecalis is the most frequently detected species in root canal-treated teeth, and it is able to survive under starvation conditions. However, persistent periapical disease is often caused by multispecies. The aim of this study was to explore the survival of E. faecalis in starvation conditions and biofilm formation with the 4 common pathogenic species. METHODS: A dual-species model of Candida albicans, Streptococcus gordonii, Actinomyces viscosus, or Lactobacillus acidophilus in combination with E. faecalis was established and allowed to grow in phosphate-buffered saline for the examination of starvation survival. Cefuroxime sodium and vancomycin at a concentration of 100 mg/L were added into brain-heart infusion plate agar to count the 2 bacteria separately in the dual species. Scanning electron microscopy was used to observe the dual species and multiple species on the root canal dentin of bovine teeth for 48 hours. A confocal laser scanning microscope was used to show the 4 groups of dual-species biofilms on substrates with glass bottoms for 48 hours. RESULTS: E. faecalis was more resistant to starvation in coexistence with C. albicans, S. gordonii, A. viscosus, or L. acidophilus, and S. gordonii was completely inhibited in coexistence with E. faecalis. The dual-species biofilm showed that E. faecalis formed thicker and denser biofilms on the root canal dentin and glass slides in coexistence with S. gordonii and A. viscosus than C. albicans and L. acidophilus. CONCLUSIONS: The multispecies community is conducive to the resistance to starvation of E. faecalis and biofilm formation in root canals.

Short-term effects of calcium ions on the apoptosis and onset of mineralization of human dental pulp cells in vitro and in vivo.

Calcium ions (Ca2+) are a major constituent of most pulp-capping materials and have an important role in the mineralization of human dental pulp cells (hDPCs). A previous study by our group has shown that increased levels of Ca2+ can promote hDPC-mediated mineralization in long-term cultures (21 days). However, the initiation of mineralization occurs in the early stage of osteogenic inductive culture, and the effects of Ca2+ on the mineralization of hDPCs in short-term cultures (five days) have not been studied in detail. Furthermore, the underlying mechanism by which Ca2+ stimulates the mineralization of hDPCs has remained controversial. A strong correlation between mineralization and cell apoptosis and/or death has been identified. Thus, the present study hypothesized that Ca2+ may promote the onset of hDPC-mediated mineralization through inducing their apoptosis and/or death. To verify this hypothesis, Ca2+ was added to the growth culture medium and osteogenic culture medium at various concentrations. Alizarin Red S staining and reverse transcription-polymerase chain reaction analysis were used to evaluate the onset of mineralization. Furthermore, the cell counting kit-8 and fluorescein isothiocyanate-Annexin V/propidium iodide double-staining method were adopted to detect the proliferation and apoptosis of hDPCs in the growth culture medium. An animal experiment and scanning electron microscopic observation of ceramic graft implants were applied to measure the mineralization in vivo. The results showed that 5.4 and 9.0 mM Ca2+ accelerated the onset of mineralized matrix nodule formation, promoted osteopontin mRNA expression and induced marked cell apoptosis and necrosis, but had no obvious effect on cell proliferation. These findings indicated a positive association between cell apoptosis and/or death and the timing of formation as well as the quantity of extracellular mineralization induced by Ca2+ in short-term cultured hDPCs.