Silencing DDX3 Attenuates Interleukin-1ß-Induced Intervertebral Disc Degeneration Through Inhibiting Pyroptosis.

Intervertebral disc degeneration (IVDD) is a common disorder associated with chronic inflammation and cell death. In this study, an IVDD rat model was created through Interleukin-1ß (IL-1ß) injection. The degeneration of intervertebral disc tissues was assessed using magnetic resonance imaging (MRI), followed by hematoxylin and eosin (H&E) and terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) staining. RNA sequencing was performed to identify differentially expressed genes (DEGs) between the IVDD model and control rats. The expression levels of DEGs (DEAD-box polypeptide 3 (DDX3), lysine-specific demethylase 5D (KDM5D), interferon-induced gene-1 (IFIT1), ribosomal protein S10 (RPS10), tenomodulin (TNMD), and pentraxin 3 (PTX3)) were measured by real-time quantitative polymerase chain reaction (RT-qPCR). The regulatory effect of DDX3 on pyroptosis in IL-1ß-treated nucleus pulpous (NP) cells was assessed after transfection with siRNA of DDX3. A total of 601 DEGs were identified from the IVDD model rat, and were abundant in extracellular matrix (ECM) organization, ECM-receptor interaction, and inflammatory pathways, including the PI3K-Akt, TNF, and AMPK signaling pathways. DDX3, KDM5D, and IFIT1 levels were notably elevated, whereas RPS10, TNMD, and PTX3 levels were decreased in the IL-1ß-induced IVDD rat model. Moreover, silencing DDX3 promoted cell proliferation and abolished IL-1ß-induced cell apoptosis and pyroptosis. This study revealed the role of DDX3 in IVDD pyroptosis, providing potential target for IVDD management.

Synthesis of Fluorine-Containing Multisubstituted Oxa-Spiro[4,5]cyclohexadienones via a Fluorinated Alcohol-Catalyzed One-Pot Sequential Cascade Strategy.

In recent years, the application of fluorinated alcohols as solvents, cosolvents, or additives has become important in modern organic synthesis. However, their potential as efficient catalysts in organic synthesis has not been well-explored. In this article, we report on the development of a one-pot sequential cascade reaction of p-quinone methides with difluoroenoxysilanes using hexafluoroisopropanol as catalyst. This reaction allows for the preparation of fluorinated multisubstituted oxa-spiro[4,5]cyclohexadienones. By using 50 mol % 1,1,1,3,3,3-Hexafluoroisopropanol (HFIP), the reaction proceeds smoothly to yield 1,6-conjugated products, which are then subjected to oxidative dearomatization/hemiacetalization using PhI(OAc)2. The overall process affords moderate to high yields and excellent diastereoselectivities.

Acquired tonsillar herniation related to spontaneous intracranial hypotension: case reports.

Background: Acquired prolapse of the cerebellar tonsils in spontaneous intracranial hypotension (SIH) patients is rare. This study aims to evaluate neuroimaging changes of acquired prolapse of the cerebellar tonsils below the foramen magnum in SIH patients due to spontaneous spinal cerebrospinal fluid leakage, which was treated by targeted epidural blood patches (EBP). Methods: We retrospectively reviewed clinical and neuroimaging characteristics of 5 cases of SIH with acquired prolapse of the cerebellar tonsils that received targeted EBP in our institution from January 2013 to December 2016. Results: Of these SIH patients, all of them suffered from an orthostatic headache. Initial cranial MRI demonstrated descent of the cerebellar tonsils ≥5 mm. Intrathecal gadolinium-enhanced spinal MR myelography and/or spinal MR hydrography were performed to evaluate the level of spinal cerebrospinal fluid leakage. Symptoms were alleviated in all 5 patients after two (n = 4), or three (n = 1) targeted EBP during hospitalization. Follow-up cranial MRI revealed that the descent of cerebellar tonsils was reversed after EBP treatment. Conclusion: Acquired tonsillar herniation can occur in patients with SIH and spinal cerebrospinal fluid leakage. Symptoms of these patients may be resolved and radiologic findings may be reversed after EBP treatment.

Nomogram to predict severe retinopathy of prematurity in Southeast China.

AIM: To define the predictive factors of severe retinopathy of prematurity (ROP) and develop a nomogram for predicting severe ROP in southeast China. METHODS: Totally 554 infants diagnosed with ROP hospitalized in the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University and hospitalized in Taizhou Women and Children's Hospital were included. Clinical data and 43 candidate predictive factors of ROP infants were collected retrospectively. Logistic regression model was used to identify predictive factors of severe ROP and to propose a nomogram for individual risk prediction, which was compared with WINROP model and Digirop-Birth model. RESULTS: Infants from the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University (n=478) were randomly allocated into training (n=402) and internal validation group (n=76). Infants from Taizhou Women and Children's Hospital were set as external validation group (n=76). Severe ROP were found in 52 of 402 infants, 12 of 76 infants, and 7 of 76 infants in training group, internal validation group, and external validation group, respectively. Birth weight [odds ratio (OR), 0.997; 95% confidence interval (CI), 0.996-0.999; P<0.001], multiple births (OR, 1.885; 95%CI, 1.013-3.506; P=0.045), and non-invasive ventilation (OR, 0.288; 95%CI, 0.146-0.570; P<0.001) were identified as predictive factors for the prediction of severe ROP, by univariate analysis and multivariate analysis. For predicting severe ROP based on the internal validation group, the areas under receiver operating characteristic curve (AUC) was 78.1 (95%CI, 64.2-92.0) for the nomogram, 32.9 (95%CI, 15.3-50.5) for WINROP model, 70.2 (95%CI, 55.8-84.6) for Digirop-Birth model. In external validation group, AUC of the nomogram was also higher than that of WINROP model and Digirop-Birth model (80.2 versus 51.1 and 63.4). The decision curve analysis of the nomogram demonstrated better clinical efficacy than that of WINROP model and Digirop-Birth model. The calibration curves demonstrated a good consistency between the actual severe ROP incidence and the predicted probability. CONCLUSION: Birth weight, multiple births, and non-invasive ventilation are independent predictors of severe ROP. The nomogram has a good ability to predict severe ROP and performed well on internal validation and external validation in southeast China.

Highly Diastereoselective [3 + 2] Cycloaddition of Aziridines with Difluorinated Silyl Enol Ethers: Divergent Synthesis of 4,4-Difluoropyrrolidines and 4-Fluoropyrroles.

A highly diastereoselective [3 + 2] cycloaddition of aziridines with difluorinated silyl enol ethers has been developed. This approach provides a facile methodology for highly functionalized gem-difluorinated pyrrolidines in good to excellent yields with good functional group tolerance. A one-pot, two-step approach for synthesis of structurally interesting fluorinated pyrroles has also been developed through a cycloaddition/aromatization/desulfonation sequence. Moreover, readily available substrates, mild reaction conditions, and easy scale-up synthesis show practical advantages.

A piperazine-substituted phthalocyanine with rapid cellular uptake and dual organelle-targeting for in vitro photodynamic therapy.

The rational design of photosensitizers with rapid cellular uptake and dual-organelle targeting ability is essential for enhancing the efficacy of photodynamic therapy (PDT). However, achieving this goal is a great challenge. In this paper, a novel axial piperazine substituted (PIP) silicon phthalocyanine (PIP-SiPc) has been synthesized. The PIP substitution significantly improved the cellular uptake of PIP-SiPc in MCF-7 breast cancer cells, as demonstrated by two-photon fluorescence imaging combined with fluorescence correlation spectroscopy. Additionally, PIP-SiPc was able to target both mitochondria and lysosomes simultaneously. Notably, PIP-SiPc exhibited remarkable singlet oxygen generation ability, leading to apoptosis in cancer cells upon irradiation, with an IC50 value of only 0.2 µM. These findings highlight the effectiveness of PIP-SiPc as a multifunctional photosensitizer for PDT.

Stem cells in central nervous system diseases: Promising therapeutic strategies.

Central nervous system (CNS) diseases are a leading cause of death and disability. Due to CNS neurons have no self-renewal and regenerative ability as they mature, their loss after injury or disease is irreversible and often leads to functional impairments. Unfortunately, therapeutic options for CNS diseases are still limited, and effective treatments for these notorious diseases are warranted to be explored. At present, stem cell therapy has emerged as a potential therapeutic strategy for improving the prognosis of CNS diseases. Accumulating preclinical and clinical evidences have demonstrated that multiple molecular mechanisms, such as cell replacement, immunoregulation and neurotrophic effect, underlie the use of stem cell therapy for CNS diseases. However, several issues have yet to be addressed to support its clinical application. Thus, this review article aims to summarize the role and underlying mechanisms of stem cell therapy in treating CNS diseases. And it is worthy of further evaluation for the potential therapeutic applications of stem cell treatment in CNS disease.

Temporal dynamics of microglia-astrocyte interaction in neuroprotective glial scar formation after intracerebral hemorrhage.

The role of glial scar after intracerebral hemorrhage (ICH) remains unclear. This study aimed to investigate whether microglia-astrocyte interaction affects glial scar formation and explore the specific function of glial scar. We used a pharmacologic approach to induce microglial depletion during different ICH stages and examine how ablating microglia affects astrocytic scar formation. Spatial transcriptomics (ST) analysis was performed to explore the potential ligand-receptor pair in the modulation of microglia-astrocyte interaction and to verify the functional changes of astrocytic scars at different periods. During the early stage, sustained microglial depletion induced disorganized astrocytic scar, enhanced neutrophil infiltration, and impaired tissue repair. ST analysis indicated that microglia-derived insulin like growth factor 1 (IGF1) modulated astrocytic scar formation via mechanistic target of rapamycin (mTOR) signaling activation. Moreover, repopulating microglia (RM) more strongly activated mTOR signaling, facilitating a more protective scar formation. The combination of IGF1 and osteopontin (OPN) was necessary and sufficient for RM function, rather than IGF1 or OPN alone. At the chronic stage of ICH, the overall net effect of astrocytic scar changed from protective to destructive and delayed microglial depletion could partly reverse this. The vital insight gleaned from our data is that sustained microglial depletion may not be a reasonable treatment strategy for early-stage ICH. Inversely, early-stage IGF1/OPN treatment combined with late-stage PLX3397 treatment is a promising therapeutic strategy. This prompts us to consider the complex temporal dynamics and overall net effect of microglia and astrocytes, and develop elaborate treatment strategies at precise time points after ICH.

Multicomponent Dearomative Difluoroalkylation of Isoquinolines with Difluorinated Silyl Enol Ethers: Divergent Synthesis of gem-Difluorinated Heterocycles.

A multicomponent dearomative difluoroalkylation of isoquinolines has been developed with difluorinated silyl enol ethers serving as poor nucleophiles without an additional transition-metal or organic catalyst. The sequential oxidative rearomatization under different alkaline conditions provides a controllable formal C-H difluoroalkylation and difluoromethylation method for isoquinolines without peroxide or metal oxidant. A series of isoquinolines including a pharmaceutical, phenanthridine, quinolines, and difluorinated silyl enol ethers were suitable substrates to construct gem-difluorinated heterocycles. The inexpensive starting materials, mild reaction conditions, and simple operation also show practical and environmentally benign advantages.

Using multiple indicators to predict the risk of surgical site infection after ORIF of tibia fractures: a machine learning based study.

Objective: Surgical site infection (SSI) are a serious complication that can occur after open reduction and internal fixation (ORIF) of tibial fractures, leading to severe consequences. This study aimed to develop a machine learning (ML)-based predictive model to screen high-risk patients of SSI following ORIF of tibial fractures, thereby aiding in personalized prevention and treatment. Methods: Patients who underwent ORIF of tibial fractures between January 2018 and October 2022 at the Department of Emergency Trauma Surgery at Ganzhou People's Hospital were retrospectively included. The demographic characteristics, surgery-related variables and laboratory indicators of patients were collected in the inpatient electronic medical records. Ten different machine learning algorithms were employed to develop the prediction model, and the performance of the models was evaluated to select the best predictive model. Ten-fold cross validation for the training set and ROC curves for the test set were used to evaluate model performance. The decision curve and calibration curve analysis were used to verify the clinical value of the model, and the relative importance of features in the model was analyzed. Results: A total of 351 patients who underwent ORIF of tibia fractures were included in this study, among whom 51 (14.53%) had SSI and 300 (85.47%) did not. Of the patients with SSI, 15 cases were of deep infection, and 36 cases were of superficial infection. Given the initial parameters, the ET, LR and RF are the top three algorithms with excellent performance. Ten-fold cross-validation on the training set and ROC curves on the test set revealed that the ET model had the best performance, with AUC values of 0.853 and 0.866, respectively. The decision curve analysis and calibration curves also showed that the ET model had the best clinical utility. Finally, the performance of the ET model was further tested, and the relative importance of features in the model was analyzed. Conclusion: In this study, we constructed a multivariate prediction model for SSI after ORIF of tibial fracture through ML, and the strength of this study was the use of multiple indicators to establish an infection prediction model, which can better reflect the real situation of patients, and the model show great clinical prediction performance.

Synthesis of Fluorinated Pyrrolo[2,1-a]isoquinolines through Decarboxylative/Dehydrofluorinative [3 + 2] Cycloaddition Aromatization of Isoquinolinium N-Ylides with Difluoroenoxysilanes.

A decarboxylative/dehydrofluorinative formal [3 + 2] cycloaddition aromatization of isoquinolinium N-ylides with difluoroenoxysilanes has been developed. This methodology provides a facile and straightforward synthetic pathway to afford highly functionalized fluorinated pyrrolo[2,1-a]isoquinolines in good to excellent yields under mild conditions. Moreover, gram-scale and synthetic derivatization experiments for the late-stage functionalization of drug molecules have also been demonstrated.

Palladium-Catalyzed C-H Allylation/Annulation Reaction of Amides and Allylic Alcohols: Regioselective Construction of Vinyl-Substituted 3,4-Dihydroisoquinolones.

A palladium-catalyzed highly regioselective C-H allylation/annulation reaction of N-sulfonyl amides with secondary or tertiary allylic alcohols has been developed to construct 3,4-dihydroisoquinolones bearing a synthetically valuable vinyl substituent. This cascade cyclization approach of allylic alcohols involving C-H allylation has not been reported previously. The commercially available allylic alcohol substrates, the only by-product of water, and the used terminal oxidant of O2 provide environmentally benign advantages.

The Promising Hydrogel Candidates for Preclinically Treating Diabetic Foot Ulcer: A Systematic Review and Meta-Analysis.

Significance: Diabetic foot ulcer (DFU) causes high amputation rates owing to its aberrant wound healing. Traditional dressings cannot effectively contribute to DFU healing. Functional hydrogels have been proposed as a promising novel dressing to treat DFU in future, but the evidence for various hydrogels to heal DFU is still ambiguous. Recent Advances: In accordance with PRISMA and CONSORT guidelines, a meta-analysis was performed to evaluate the efficacy of functional hydrogels. Four electronic databases and one website were used for data searching. Twenty-four animal studies and six clinical trials met the inclusion criteria with a total of 399 diabetic murine models and 278 patients with DFU. Critical Issues: Functional hydrogels accelerated the healing progress for DFU and relieved symptoms in patients. According to their characteristics, the functional hydrogels were divided into antioxidant hydrogel (AOH), antibacterial hydrogel (ABH), multifunctional hydrogel (MFH), proangiogenic hydrogel, and hydrogel promoting proliferation (PPH). By network meta-analysis, AOH and MFH were considered the premium options for treating wounds of diabetic patients at whole stage. Future Direction: Functional hydrogels effectively accelerate healing rates in wounds of diabetic animals. Hydrogels of AOH and MFH might become the ideal candidates for clinical trials on DFU treatment, based on the meta-analyses from the reported work. Early treatment with AOH followed a week later with ABH, which might become an advanced strategy for DFU in future. This information is very important for researchers or/and physicians in taking consideration for alternate application of hydrogel dressings. Scope and Significance: The treatment of DFU imposes a huge burden on medical workers. If DFU is not treated properly, patients will have to suffer from amputation and from spiritual agony. Although various topical dressings have been designated for DFU, the healing ability of those dressings is still unknown well. In this review and meta-analysis, we quantitatively evaluated the reported outcomes of functional hydrogels, pure scaffolds, and controls in 2-week interval. Healing ability of various kinds of functional hydrogels was also assessed in different stages of wound, aiming to screen promising candidates for DFU treatment. This information is valuable in designing smart dressings for researchers or/and physicians in future. Translational Relevance: Considering many external factors like formation of bacterial film and internal factors like hyperglycemia, the progress during DFU healing could involve many biochemical aspects. Persistent inflammation, oxidation stress, and impaired angiogenesis lead to prolonged wound healing and even lethal outcomes. Thus, improvement of topical conditions and inhibition of adverse factors will lead to the alleviated morbidity and even mortality. Clinical Relevance: DFU brings about great burden on patients and medical staffs because of high morbidity and poor prognosis. Improper and powerless treatment might induce high rates of amputation and mortality. Functional hydrogels, mimicking extracellular matrices, would provide the tissue with suitable media and functions to promote DFU healing. The application of various types of hydrogels could be a promising solution to heal DFU and reduce adverse events and costs.

The osteogenesis and the biologic mechanism of thermo-responsive injectable hydrogel containing carboxymethyl chitosan/sodium alginate nanoparticles towards promoting osteal wound healing.

With the development of minimally invasive orthopedics, injectable materials for bone repair are attracted more attention, especially for those wound with a small external mouth and sizeable internal cavity. In this work, the hydrogel with features of thermo-responsiveness, degradability and injectability was designed and fabricated. The hydrogel, named as FHCS, is composed of Pluronic F-127 (F127) loaded with carboxymethyl chitosan/sodium alginate nanoparticles (nCS) and nanohydroxyapatite (nHA). The hydrogel FHCS was non-toxic and good hemocompatible. It can enhance the ALP activity and extracellular matrix calcification of MC3T3-E1 due to the chitosan-based nanoparticle components (nCS). Moreover, FHCS-5 (containing 5 mg/mL nCS) showed relative high expression of osteogenic genes and protein markers. Osteal regeneration was observed treated by FHCS-5 hydrogel in a critical-size rat calvarial bone defect model. CT scanning showed that the whole defect was basically covered by new bone after FHCS-5 hydrogel. The results of H&E staining and Masson's trichrome staining on histological sections further confirmed that FHCS-5 hydrogel promoted new osteal formation and maturation, which up regulated the osteogenic related genes and proteins of ALP, OCN, OPN through BMP/Smad signaling pathway. Hence, this study suggests that FHCS-5 hydrogels have a promising application for non-loading bone regeneration.

Elevated retinal retinol-binding protein 4 levels in diabetic mice can induce retinal neurodegeneration through microglia.

Retinol-binding protein 4 (RBP4) is the sole specific transport protein for vitamin A (retinol), but it is also an adipokine with retinol-independent, proinflammatory activity associated with diabetes and diabetic retinopathy (DR). Most previous studies focused on the relationship between elevated serum RBP4 levels and DR. Since serum RBP4 cannot cross the blood-retinal barrier, the level of retinal RBP4 is independent of serum RBP4, and the change of retinal RBP4 and its potential pathogenic mechanism in DR has not been studied. We showed that the retinal RBP4 levels were raised in Streptozotocin-induced diabetic mice though the serum RBP4 levels were decreased. Intravitreal injection of RBP4 protein in mice results in activation of microglia, loss of retinal ganglion cells (RGCs) and bipolar cells. Minocycline (MC) can reverse the activation of microglia induced by RBP4, protecting RGCs and bipolar cells. These findings suggest that retinal RBP4 levels were raised in diabetic mice, and RBP4 can directly induce retinal neurodegeneration in mice through microglia. RESEARCH HIGHLIGHTS: We revealed that the retinal RBP4 levels were raised in diabetes and elevated retinal RBP4 can induce retinal neurodegeneration through microglia. Inhibition of neuroinflammation or reduction of retinal RBP4 level may be a potential therapeutic strategy to prevent diabetic retinal neurodegeration.

Melatonin as an Antioxidant Agent in Stroke: An Updated Review.

Stroke is a devastating disease associated with high mortality and disability worldwide, and is generally classified as ischemic or hemorrhagic, which share certain similar pathophysiological processes. Oxidative stress is a critical factor involved in stroke-induced injury, which not only directly damages brain tissue, but also enhances a series of pathological signaling cascades, contributing to inflammation, brain edema, and neuronal death. To alleviate these serious secondary brain injuries, neuroprotective agents targeting oxidative stress inhibition may serve as a promising treatment strategy. Melatonin is a hormone secreted by the pineal gland, and has various properties, such as antioxidation, anti-inflammation, circadian rhythm modulation, and promotion of tissue regeneration. Numerous animal experiments studying stroke have confirmed that melatonin exerts considerable neuroprotective effects, partially via anti-oxidative stress. In this review, we introduce the possible role of melatonin as an antioxidant in the treatment of stroke based on the latest published studies of animal experiments and clinical research.

Microglia and Neuroinflammation: Crucial Pathological Mechanisms in Traumatic Brain Injury-Induced Neurodegeneration.

Traumatic brain injury (TBI) is one of the most common diseases in the central nervous system (CNS) with high mortality and morbidity. Patients with TBI usually suffer many sequelae in the life time post injury, including neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD). However, the pathological mechanisms connecting these two processes have not yet been fully elucidated. It is important to further investigate the pathophysiological mechanisms underlying TBI and TBI-induced neurodegeneration, which will promote the development of precise treatment target for these notorious neurodegenerative consequences after TBI. A growing body of evidence shows that neuroinflammation is a pivotal pathological process underlying chronic neurodegeneration following TBI. Microglia, as the immune cells in the CNS, play crucial roles in neuroinflammation and many other CNS diseases. Of interest, microglial activation and functional alteration has been proposed as key mediators in the evolution of chronic neurodegenerative pathology following TBI. Here, we review the updated studies involving phenotypical and functional alterations of microglia in neurodegeneration after injury, survey key molecules regulating the activities and functional responses of microglia in TBI pathology, and explore their potential implications to chronic neurodegeneration after injury. The work will give us a comprehensive understanding of mechanisms driving TBI-related neurodegeneration and offer novel ideas of developing corresponding prevention and treatment strategies for this disease.

Divergent Synthesis of gem-Difluorinated Oxa-Spirocyclohexadienones by One-Pot Sequential Reactions of p-Hydroxybenzyl Alcohols with Difluoroenoxysilanes.

A new efficient formal [2 + 3] cyclization of p-hydroxybenzyl alcohols with difluoroenoxysilanes has been established. This convenient one-pot sequential procedure enables the divergent construction of highly functionalized gem-difluorinated oxa-spirocyclohexadienones under mild conditions. As opposed to the common C1 synthons in previous studies, difluoroenoxysilanes acted as new 3-atom (CCO) synthons for the first time here. The AcOH and H2O generated in the reaction are critical for the reactions to proceed smoothly.