Induced Huge Optical Activity in Nanoplatelet Superlattice.

Chiral superstructures with unique chiroptical properties that are not inherent in the individual units are essential in applications such as 3D displays, spintronic devices, biomedical sensors, and beyond. Generally, chiral superstructures are obtained by tedious procedures exploring various physical and chemical forces to break spatial symmetry during the self-assembly of discrete nanoparticles. In contrast, we herein present a simple and efficient approach to chiral superstructures by intercalating small chiral molecules into preformed achiral superstructures. As a model system, the chiral CdSe nanoplatelet (NPL) superlattice exhibits a giant and tunable optical activity with the highest g-factor reaching 3.09 × 10-2 to the excitonic transition of the NPL superlattice, nearly 2 orders of magnitude higher than that of the corresponding separated chiral NPLs. The theoretical analysis reveals that the chiral deformation in the NPL superlattice induced by the chiral perturbation of the small chiral molecules is critical to the observed huge optical activity. We anticipate that this research lays a foundation for understanding and applying chiral inorganic nanosystems.

Flexible Full-Inorganic Ultrathin Films with Stable Circularly Polarized Luminescence Covering the Visible to Near-Infrared Region.

Circularly polarized luminescence (CPL) materials hold significant value in various fields, including information storage, secure communication, three-dimensional displays, biological detection, and optoelectronic devices. Using the Langmuir-Schaeffer (LS) assembly technique, we successfully construct a series of large-area flexible optical ultrathin films. Impressively, the inorganic assembled ultrathin films exhibit excellent CPL optical activity covering the visible to near-infrared (NIR) region, with the luminescence asymmetry factor glum ranging from 0.59 to 0.72. Moreover, such ultrathin films also display outstanding mechanical flexibility, the optical activity of which even after 240 bending cycles shows almost no difference compared to the unbent samples. Owing to the ultra-broadband optical activity and ultra-stable optical activity of such full-inorganic assembled materials on flexible substrates, coupled with their excellent processability and outstanding mechanical flexibility, we anticipate they will find use in many fields such as communication technology and flexible optoelectronics.

Activation of Sestrin2 accelerates deep second-degree burn wound healing through PI3K/AKT pathway.

Deep second-degree burns heal slowly, and promoting the healing process is a focus of clinical research. Sestrin2 is a stress-inducible protein with antioxidant and metabolic regulatory effects. However, its role during acute dermal and epidermal re-epithelialization in deep second-degree burns is unknown. In this study, we aimed to explore the role and molecular mechanism of sestrin2 in deep second-degree burns as a potential treatment target for burn wounds. To explore the effects of sestrin2 on burn wound healing, we established a deep second-degree burn mouse model. Then we detected the expression of sestrin2 by western blot and immunohistochemistry after obtaining the wound margin of full-thickness burned skin. The effects of sestrin2 on burn wound healing were explored in vivo and in vitro through interfering sestrin2 expression using siRNAs or the small molecule agonist of sestrin2, eupatilin. We also investigated the molecular mechanism of sestrin2 in promoting burn wound healing by western blot and CCK-8 assay. Our in vivo and in vitro deep second-degree burn wound healing model demonstrated that sestrin2 was promptly induced at murine skin wound edges. The small molecule agonist of sestrin2 accelerated the proliferation and migration of keratinocytes, as well as burn wound healing. Conversely, the healing of burn wounds was delayed in sestrin2-deficient mice and was accompanied by the secretion of inflammatory cytokines as well as the suppression of keratinocyte proliferation and migration. Mechanistically, sestrin2 promoted the phosphorylation of the PI3K/AKT pathway, and inhibition of PI3K/AKT pathway abrogated the promoting role of sestrin2 in keratinocyte proliferation and migration. Therefore, sestrin2 plays a critical role in activation of the PI3K/AKT pathway to promote keratinocyte proliferation and migration, as well as re-epithelialization in the process of deep second-degree burn wound repair.

Feasibility, comparability and outcomes of three acquainted facial island flaps for periorbital defects reconstruction.

Severe coloboma of ocular malignant neoplasms post-resection poses a reconstructive challenge to surgeons. To compare the practicability, manipulability and outcomes of temporal (myocutaneous) flaps (TFs), forehead (supratrochlear artery/supraorbital artery) flaps (FFs) and buccal (facial artery) flaps (BFs) for periorbital defects reconstruction, a retrospective case series was conducted and evaluated between March 2014 and March 2021. Patient demographics and clinical parameters including age, gender, pathological diagnosis, operative methods, flap selection, operation time, aesthetic satisfaction and follow-up period were collected. The differences in complications were compared and assessed of the three flaps, including flap survival, venous congestion and donor site healing. Totally, 68 patients who underwent periorbital reconstructive operations because of common ocular malignant tumours were reviewed in this study. As for aesthetic satisfaction, a score more than "moderately dissatisfied" was obtained in 21 patients with TFs (95.5%), and of which the scores in FFs group were 12 cases (60%) and 16 cases with BFs reconstruction (61.5%) (P < .05). Severe microvascular complications underwent re-exploration operation occurred in one patient with FFs (1.5%) (P > .05). Notable flap necrosis was observed in two patients with BFs repair (2.9%) and in one case with FFs repair (1.5%), with no statistical difference between the three flap selections (P > .05). Moderate venous congestion occurred in one patient with TFs (1.5%), which was fully meliorated non-surgically. The three familiar facial island flaps are considered as minor trauma and time-saving process for reconstructing the extensive periorbital defects with comparable ranks of complications.

Mitochondrial fission factor promotes cisplatin resistancein hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the most common primary liver tumor and one of the leading causes of cancer-related death worldwide. Chemotherapeutic agents/regimens such as cisplatin (DDP) are frequently used for advanced HCC treatment. However, drug resistance remains a major hindrance and the underline mechanisms are not fully understood. In this study, we investigated the expression pattern and function of mitochondrial fission factor (Mff) in cisplatin-resistant HCC. We found that Mff is highly expressed in cisplatin-resistant HCC tissues and cell lines. Knockdown of Mff suppresses cell proliferation and promotes cell apoptosis of HCC/DDP cells. In addition, knockdown of Mff sensitizes Huh-7/DDP cells to cisplatin treatment, inhibits cell proliferation, migration and invasion, and enhances cell apoptosis. Confocal imaging showed that knockdown of Mff inhibits the mitochondrial fission and downregulates the expression of GTPase dynamin-related protein 1 (Drp1) in cisplatin-resistant Huh-7/DDP cells. Moreover, xenograft tumor model revealed that knockdown of Mff sensitizes Huh-7/DDP xenograft tumor to cisplatin treatment . In summary, our findings suggest that Mff regulates mitochondrial Drp1 expression and promotes cisplatin resistance in HCC, which provides a potential therapeutic target for the treatment of resistant HCC.

Zone-Folded Longitudinal Acoustic Phonons Driving Self-Trapped State Emission in Colloidal CdSe Nanoplatelet Superlattices.

Colloidal CdSe nanoplatelets (NPLs) have substantial potential in light-emitting applications because of their quantum-well-like characteristics. The self-trapped state (STS), originating from strong electron-phonon coupling (EPC), is promising in white light luminance because of its broadband emission. However, achieving STS in CdSe NPLs is extremely challenging because of their intrinsic weak EPC nature. Herein, we developed a strong STS emission in the spectral range of 450-600 nm by building superlattice (SL) structures with colloidal CdSe NPLs. We demonstrated that STS is generated via strong coupling of excitons and zone-folded longitudinal acoustic phonons with formation time of ∼450 fs and localization length of ∼0.56 nm. The Huang-Rhys factor, describing the EPC strength in SL structure, is estimated to be ∼19.9, which is much larger than that (∼0.1) of monodispersed CdSe NPLs. Our results provide an in-depth understanding of STS and a platform for generating and manipulating STS by designing SL structures.

Tunable Circularly Polarized Luminescence from Inorganic Chiral Photonic Crystals Doped with Quantum Dots.

Chiral semiconductor nanostructures have received enormous attention due to their emerging circularly polarized luminescence (CPL) properties. However, compared with well-studied photoluminescence (PL), the reported CPL is much weaker and more challenging to be modulated. Herein, we describe a new approach for acquiring the intense and tunable CPL from inorganic chiral photonic crystals (CPCs) doped with semiconductor quantum dots (QDs). Unprecedentedly, the sign, position and intensity of CPL peaks can be precisely controlled by manipulating either the photonic band gap of CPCs or luminescence wavelength of QDs and a giant absolute dissymmetry factor |glum | up to 0.25 is obtained. More importantly, the origin of the CPL modulation is clearly elucidated by both experiment and theory. This work lays the foundation for the construction of next-generation high-performance CPL-based devices.

A retrospective study to identify the optimal parameters for pulsed dye laser in the treatment of hypertrophic burn scars in Chinese children with Fitzpatrick skin types III and IV.

For over several decades, 595-nm pulsed dye laser (PDL) has been used effectively, reducing erythema and improving the pliability and texture of burn scars. Children usually tolerate PDL treatment as it is non-invasive and causes only mild pain compared to other laser treatments. However, currently, there are limited data on scar management in children who underwent PDL treatment, especially for Fitzpatrick skin types III and IV. The objective of the study was to identify the optimal parameters for the PDL treatment that induce inhibitory effects on scar tissue in children with Fitzpatrick skin types III and IV. Besides, the study assessed the usefulness of high-frequency ultrasound (20 MHz) and laser Doppler flowmetry in assessing these lesions. A total of 165 (79 males and 86 females) children with hypertrophic scars treated by PDL were assessed by the Vancouver scar scale (VSS), high-frequency ultrasound (20 MHz), and laser Doppler flowmetry. The parameters used for the 595-nm PDL treatment were pulse duration of 0.45 ms, fluence between 5 and 9 J/cm2, a spot size of 7 mm, and treatment intervals from 3 to 8 weeks. There were no significant differences between pretreatment and post-treatment in terms of the distribution of sex, type of skin color, and low and high fluences. While the mean scores of all scar parameters based on VSS, except thickness and pliability between pre and post-treatment, showed significant differences in ≤3-year-old children vs. to >3-year-old children, except for the subscore, a significant improvement was observed when PDL was initiated within 4 to 6 months of the scar age. In Chinese children with Fitzpatrick skin types III and IV, early intervention, appropriate treatment intervals, and low fluence of PDL were optimal parameters in treating hypertrophic burn scars. The combined high-frequency ultrasound and laser Doppler flowmetry assessment of scars helped assess these lesions and compare the efficacy of different treatment modalities.

ING4 alleviated lipopolysaccharide-induced inflammation by regulating the NF-κB pathway via a direct interaction with SIRT1.

Sepsis is a complex inflammatory disorder in which high mortality is associated with an excessive inflammatory response. Inhibitor of growth 4 (ING4), which is a cofactor of histone acetyltransferase and histone deacetylase complexes, could negatively regulate this inflammation. However, the exact molecular signaling pathway regulated by ING4 remains uncertain. As a pivotal histone deacetylase, Sirtuin1 (SIRT1), which is widely accepted to be an anti-inflammatory molecule, has not been found to be linked to ING4. This study investigated how ING4 is involved in the regulation of inflammation by constructing lipopolysaccharide (LPS)-induced macrophage and mouse sepsis models. Our results revealed that ING4 expression decreased, whereas the levels of proinflammatory cytokines increased in LPS-stimulated cultured primary macrophages and RAW 264.7 cells. ING4 transfection was confirmed to alleviate the LPS-induced upregulation of proinflammatory cytokine expression both in vitro and in vivo. In addition, ING4-overexpressing mice were hyposensitive to an LPS challenge and displayed reduced organ injury. Furthermore, immunoprecipitation indicated a direct interaction between ING4 and the SIRT1 protein. Moreover, ING4 could block nuclear factor-kappa B (NF-κB) P65 nuclear translocation and restrict P65 acetylation at lysine 310 induced by LPS treatment. These results are the first to clarify that the anti-inflammatory role of ING4 is associated with SIRT1, through which ING4 inhibits NF-κB signaling activation. Our studies provide a novel signaling axis involving ING4/SIRT1/NF-κB in LPS-induced sepsis.

Encapsulation of troglitazone and AVE0991 by gelation microspheres promotes epithelial transformation of adipose-derived stem cells.

Deformities in human soft tissue caused by trauma or burn present a difficult problem in plastic surgery. In this study, we encapsulated troglitazone and angiotensin 1-7 mimetic AVE0991 in gelation microspheres with the goal of inducing epithelial transformation for potential applications in tissue reconstruction. After troglitazone or AVE0991 were encapsulated to gelation microspheres, their release kinetics and bioactivity were examined. Surface morphology and diameter of the gelation microspheres were evaluated using light microscopy. The release of the drugs was assessed in the presence of human adipose-derived stem cells (ADSCs). Treatment with troglitazone microspheres increased cell viability and activated the ß-catenin in ADSCs. Moreover, the AVE0991 microspheres also increased cell viability and C-myc expression of ADSCs. These results showed that troglitazone and AVE0991 microspheres promoted the activity of ADSCs. Furthermore, ADSCs were co-treated with troglitazone and AVE0991 microspheres. Western blot and immunofluorescent staining showed that co-treatment with troglitazone and AVE0991 microspheres elevated the expression of epithelialization associated protein CK14 in ADSCs. In conclusion, our findings indicate that microspheres with troglitazone and AVE0991 can significantly improve the viability and epithelialization of ADSCs, which provides a new approach for the construction of tissue-engineered skin.

Surgical Reconstruction of Complex Distal Foot Defects With Vascularized Fascia Lata.

BACKGROUND: Reconstruction of distal foot defect remains a challenge in plastic surgery. The purpose of this report is to present a new procedure that repairs these defects in severe burn patients. Results of application and follow-up in 7 patients were presented. METHODS: From January 2016 to March 2018, a total of 7 patients (age ranging from 21 to 57 years) with distal foot defects were treated in our department. All the wounds were caused by severe burns and repaired by the free vascularized fascia lata combined with thin split-skin graft. After the operation, the status of the fascia flaps and grafted skin was observed, and follow-up information and complications were documented. RESULTS: Among the 7 patients, the flaps and grafted skins completely survived in 5 patients. One patient was found to have grafted skin necrosis in the perioperative period, and 1 patient was found to have partial flap necrosis in the follow-up period. After conventional dressing treatment and skin grafting, the wounds healed in both patients. The mean follow-up was 6 months. CONCLUSIONS: The method of combining the free vascularized fascia lata with thin split-skin graft represents a satisfactory approach for the repairing of distal foot defects.

Rational Design of a Two-Photon Fluorogenic Probe for Visualizing Monoamine Oxidase†A Activity in Human Glioma Tissues.

Monoamine oxidases have two functionally distinct but structurally similar isoforms (MAO-A and MAO-B). The ability to differentiate them by using fluorescence detection/imaging technology is of significant biological relevance, but highly challenging with available chemical tools. Herein, we report the first MAO-A-specific two-photon fluorogenic probe (F1), capable of selective imaging of endogenous MAO-A enzymatic activities from a variety of biological samples, including MAO-A-expressing neuronal SY-SY5Y cells, the brain of tumor-bearing mice and human Glioma tissues by using two-photon fluorescence microscopy (TPFM) with minimal cytotoxicity.

Perspective of Chiral Colloidal Semiconductor Nanocrystals: Opportunity and Challenge.

Chiral colloidal semiconductor nanocrystals (NCs) are an emerging type of chiral materials. These chiral NCs exhibit unique quantum confinement-determined optical activity and have aroused much interest in the multidisciplinary fields of chemistry, physics and biology. Herein, the state-of-the-art progresses of their rational synthesis, fundamental understanding and potential application are summarized. In addition, a personal view about the future development of chiral semiconductor NCs is offered.

Construction and validation of the CRISPR/dCas9-EZH2 system for targeted H3K27Me3 modification.

Cell phenotypes are closely related to the epigenome, which could be precisely regulated by the targeted manipulation of epigenetic marks. Here, we have successfully produced a targeted histone methylation system, which consists of nuclease-null dCas9 protein, the sgRNA fused with PP7 RNA aptamers and the Enhancer of Zeste Homolog 2 (EZH2) fused to PP7 coat protein (PCP). Guided by the dCas9/sgRNA-PP7, the PCP-EZH2 can specifically target gene loci to catalyze 3 methylation of histone H3 lysine 27, resulting in the inhibition of gene expression. This kind of gene inhibition system is supposed to be highly effective, specific and flexible. As a proof-of-concept study, sgRNA targeting C/ebpα promoter region was designed. In the cells co-infected with the dCas9, sgRNA/C/ebpα-PP7 and PCP-EZH2, the expression of C/ebpα gene was significantly reduced via induction of trimethylation to H3K27 on C/ebpα promoter, with the results epigenetically inherited in the daughter cells. In conclusion, our results successfully established a gene modification system consisting of dCas9/sgRNA-PP7 and PCP-EZH2, providing a robust tool for targeted manipulation of gene epigenetic modification and expression.

Linagliptin inhibits high glucose-induced transdifferentiation of hypertrophic scar-derived fibroblasts to myofibroblasts via IGF/Akt/mTOR signalling pathway.

Hypertrophic scar (HS) is a fibroproliferative disease after serious burns; the underlying mechanism remains unknown. The study was performed to clarify the effect of high glucose (HG) on HS. The expression of Col1, Col3 and α-SMA was upregulated in HS-derived fibroblasts (HSF) exposed to HG (20 and 30 mmol/L), and HG activated the phosphorylated protein expression of IGF/Akt/mTOR signalling pathway in HSF. Dpp4, a marker targeted the treatment of diabetes mellitus, was overexpressed in HG-induced HSF. Linagliptin, a Dpp4 inhibitor, played the antifibrotic role in HSF exposed to HG, the levels of Col1, Col3 and α-SMA were significantly downregulated, and the cell proliferation and migration were also inhibited. Furthermore, linagliptin alleviated the phosphorylated protein expression of IGF/Akt/mTOR signalling pathway. Moreover, the mTOR inhibitor (rapamycin) mimicked the effect of linagliptin on the collagen and α-SMA that means linagliptin may inhibit HG-induced transdifferentiation of HSF to myofibroblasts via IGF/Akt/mTOR signalling pathway.

Biomimetic Chiral Photonic Crystals.

Although it is well known that the amazing iridescent colors of the cuticle of beetles reflect the intricate nanoscale organization of bio-fibers, artificial inorganic materials with comparable optical responses have not yet been synthesized from abiotic nanoscale building blocks. Such materials could find broad applications, including in circular polarizers, to generate circularly polarized luminescence, or in lasers. Herein, we describe a general method for the fabrication of biomimetic chiral photonic crystals by Langmuir-Schaefer assembly of colloidal inorganic nanowires. We not only reproduced the intricate helical structure and circularly polarized color reflection observed in beetles, but also achieved the highest chiroptical activity with a dissymmetry factor of -1.6 ever reported for chiral inorganic nanostructures. More importantly, the programmable structural control based on the precise interlayer arrangement endows us with unprecedented freedom to manipulate the optical activity of as-fabricated chiral photonic crystals.

Free vascularized fascia flap combined with skin grafting for deep toe ulcer in diabetic patients.

BACKGROUND: This study introduces a technique for the reconstruction of deep toe defects in diabetic patients using a method that combines free vascularized fascia flap with skin grafting. METHODS: In this retrospective study, conducted between March 2010 and February 2016, 15 diabetic patients with deep toe ulcer received surgeries that combined free vascularized fascia flap with skin grafting, including nine anterolateral thigh fascia lata flaps and six superficial temporal fascia flaps. Their medical records were systematically reviewed from electronic databases. The donor artery was anastomosed to the dorsalis pedis artery in an end-to-side manner, and the vein was anastomosed to the accompanying vein in an end-to-end manner. RESULTS: Thirteen fascia flaps completely survived without any rejection. Partially necrosed grafted skins, which were found in two cases, were healed after routine dressing changes. Patients achieved an esthetic outcome and acceptable functions without further revisions. Two patients suffered from ischemic necrosis of the fascia flap and eventually underwent amputation. CONCLUSIONS: The present study demonstrated that vascularized fascia flap combined with skin grafting has great advantages for correcting deep toe ulcer in diabetic patients characterized by the esthetic outcome, abundant vascularity, surgical simplicity, and good deformability.

Intense pulsed light is effective in treating postburn hyperpigmentation and telangiectasia in Chinese patients.

Intense pulsed light (IPL) has been used to treat postinflammatory hyperpigmentation and telangiectasia in Fitzpatrick type I -II skin. However, its therapeutic effects after superficial second-degree burns in Asian populations with Fitzpatrick type III-IV skin are uncertain. Thirty-five Han Chinese patients with facial or hand hyperpigmentation and telangiectasia due to second-degree fire burns received treatment with IPL. Each patient underwent 2-6 treatments over 3-5 weeks. The laser wavelength was 560-615 nm. Skin pigmentation was evaluated by two plastic surgeons as well as by the patients themselves (self-evaluation) before treatment at the end of the treatment cycle and 1 year after the first treatment. Blood flow in telangiectasia skin was measured by laser Doppler flow. The results showed that IPL significantly lessened hyperpigmentation so that close to normal skin color was achieved after the treatment cycles, and pigmentation did not reoccur 1 year after the first treatment. Approximately 82.9% of the patients were satisfied with their treatment outcomes. There were no post-treatment complications. Doppler showed a significant decreased blood flow in telangiectasia after treatment. In conclusion, IPL is an effective and safe modality for Chinese patients with hyperpigmentation and telangiectasia after fire burns.

Protective effect of crocetin against burn-induced intestinal injury.

BACKGROUND: Oxidative stress and inflammation exert central roles in burn-induced intestinal injury. Crocetin, a natural carotenoid compound from gardenia fruits and saffron, has been shown to inhibit oxidative stress and inflammatory response. However, the possibility of crocetin to be used in the treatment of intestinal injury after burn injury has not been investigated. The purpose of the present study was to investigate the effects and potential mechanisms of crocetin in burn-induced intestinal injury. MATERIALS AND METHODS: Several free radical-generating and lipid peroxidation models were used to systematically assess the antioxidant activities of crocetin in vitro. A common burn model was used to induce the intestinal injury in rats. Changes in the levels of malondialdehyde, superoxidase dismutase, catalase, glutathione peroxidase, tumor necrosis factor α, interleukin 6, polymorphonuclear neutrophil accumulation, intestinal permeability, and intestinal histology were examined. RESULTS: In several models of antioxidant activity, crocetin exhibited marked inhibitory action against free radicals and lipid peroxidation. Crocetin increased levels of antioxidant enzymes and reduced intestinal oxidative injury in burn models. In addition, crocetin inhibited polymorphonuclear neutrophil accumulation, ameliorated tumor necrosis factor α and interleukin 6 levels, intestinal permeability, and histological changes. CONCLUSIONS: Crocetin treatment may protect against burn-induced small intestinal injury, possibly by inhibiting burn-induced oxidative stress and inflammatory response.

ROS-Mediated NLRP3 Inflammasome Activity Is Essential for Burn-Induced Acute Lung Injury.

The NLRP3 inflammasome is necessary for initiating acute sterile inflammation. However, its role in the pathogenesis of burn-induced acute lung injury (ALI) is unknown. This study aimed to determine the role of the NLRP3 inflammasome and the signaling pathways involved in burn-induced ALI. We observed that the rat lungs exhibited enhanced inflammasome activity after burn, as evidenced by increased levels of NLRP3 expression and Caspase-1 activity and augmented inflammatory cytokines. Inhibition of NLRP3 inflammasome by BAY11-7082 attenuated burn-induced ALI, as demonstrated by the concomitant remission of histopathologic changes and the reduction of myeloperoxidase (MPO) activity, inflammatory cytokines in rat lung tissue, and protein concentrations in the bronchoalveolar lavage fluid (BALF). In the in vitro experiments, we used AMs (alveolar macrophages) challenged with burn serum to mimic the postburn microenvironment and noted that the serum significantly upregulated NLRP3 inflammasome signaling and reactive oxygen species (ROS) production. The use of ROS scavenger N-acetylcysteine (NAC) partially reversed NLRP3 inflammasome activity in cells exposed to burn serum. These results indicate that the NLRP3 inflammasome plays an essential role in burn-induced ALI and that burn-induced NLRP3 inflammasome activity is a partly ROS-dependent process. Targeting this axis may represent a promising therapeutic strategy for the treatment of burn-induced ALI.