Viscoelastic properties of decellularized and freeze-dried human dermis between i909c and 40cC.

BACKGROUND: Human donor skin is processed to make the acellular dermis matrix (ADM) for tissue repair and regeneration. There is no data on the viscoelastic properties of ADM at room and subzero temperatures. OBJECTIVE: The work evaluated the temperature dependence of viscoelastic properties of freeze-dried ADM. MATERIALS AND METHODS: Donor skin was de-epidermized, de-cellularized and freeze-dried with trehalose as the lyo-protectant. Glass transition of freeze-dried ADM was measured by differential scanning calorimeter (DSC), and viscoelastic properties were examined by dynamic mechanical analyzer (DMA). RESULTS: At the low moisture range (1.4 +/- 0.5%), the glass transition temperature (Tg) of freeze-dried ADM was 90 degree C to 100 degree C. As the moisture content increased, the Tg decreased steadily. At the high moisture range (10.8 +/- 2.9%), the Tg was 40 degree C to 60 degree C. There were large donor-to-donor variations in viscoelastic properties of freeze-dried ADM as demonstrated by the changes in storage modulus (G'), loss modulus (G") and damping factor tan delta (G"/G'). However, the trends of the temperature dependence for G', G" and tan delta were similar among all 8 donors. For each donor, changes in G' and G" were relatively small between -90 degree C and 40 degree C, and G' was at least one order of magnitude greater than G". Two viscoelastic relaxations were observed in freeze-dried ADM, one at -20 degree C and the other at -60 degree C respectively. CONCLUSION: Freeze-dried ADM was protected in the glassy carbohydrate matrix. DMA observed two viscoelastic relaxations (i.e., alpha process at -20 degree C and beta process at -60 degree C). Overall changes in G' and G'' of freeze-dried ADM were relatively small within one order of magnitude between -90 degree C and 40 degree C. https://doi.org/10.54680/fr24110110612.

[The clinical characteristics of neutrophil extracellular trap in patients with severe cerebral venous sinus thrombosis and its prognostic value in acute and subacute patients].

Objective: To explore the clinical characteristics of neutrophil extracellular trap (NET) in patients with severe cerebral venous sinus thrombosis (CVST) and to study their prognostic value in the acute and subacute phases. Methods: This study is a retrospective case series analysis. Clinical and pathological data of 52 patients with severe cerebral venous sinus thrombosis who underwent endovascular treatment in the Department of Neurosurgery, Tianjin Huanhu Hospital from June 2019 to June 2022 were retrospectively analyzed. There were 20 males and 32 females, with an age of (40.1±13.6) years(range:18 to 66 years). Forty-five healthy physical examinees were included in the control group. High-resolution MRI was used to stage the thrombus, with 11 cases in the acute group, 28 cases in the subacute group, and 13 cases in the chronic group. Thrombus specimens were obtained through endovascular treatment, and the fluorescence intensity of NET in peripheral blood at different time points was analyzed by immunofluorescence contrast,including the double-stranded DNA structure and adhesion protein components (citrolinated histone H3 (CitH3), myeloperoxidase-DNA complex(MPO-DNA), neutrophil elastase (NE)). The NET markers were determined by ELISA. Spearman rank correlation analysis was used to analyze the correlation between the NET markers in peripheral blood of patients with severe cerebral venous sinus thrombosis in the acute and subacute phases and the volume of venous sinus thrombus, the degree of venous sinus recanalization after treatment, and the discharge modified Rankin scale(mRS)score. The accuracy of NET markers in predicting the prognosis of patients with severe cerebral venous sinus thrombosis was analyzed by drawing receiver operating characteristic (ROC) curve and calculating the area under the curve (AUC). Results: The results of immunofluorescence staining and ELISA showed that no NET structure was formed in the peripheral blood of the control group, while CitH3, MPO-DNA and NE levels in the peripheral blood of CVST patients were increased, among which the acute stage group was the highest, followed by the subacute group, and the chronic group was the lowest. Spearman correlation analysis showed that CitH3, MPO-DNA and NE levels in peripheral blood of patients in acute group and subacute group were positively correlated with thrombus volume and mRS score at discharge (P<0.05). The levels of CitH3 and MPO-DNA in peripheral blood of patients with complete venous sinus recanalization were lower than those of patients with partial venous sinus recanalization (P<0.01). ROC curve analysis results showed that MPO-DNA and NE had no predictive ability for the prognosis of CVST patients (P values were 0.614 and 0.324, respectively), and the AUC of CitH3 was 0.800 (95%CI: 0.638~0.962, P=0.032), the best cut-off value was 13.5 µg/L, the sensitivity was 100%, and the specificity was 58.8%. Conclusions: A large number of NET are formed in patients with severe cerebral venous sinus thrombosis in acute stage. Patients with severe cerebral venous sinus thrombosis in acute stage and subacute stage with high peripheral blood NET content has a low rate of complete sinus revascularization and poor neurological function recovery after treatment.

[Research progress on the role of resveratrol in wound healing].

The difficulty of wound healing in patients is a difficult problem that doctors in all clinical departments may encounter, and there is still no good solution. Resveratrol is a kind of natural active substance, which has anti-inflammatory, antioxidant, antibacterial, and angiogenesis promoting effects, and is a potential drug to promote wound healing. However, the clinical application of resveratrol is limited due to its low bioavailability. In this review, the molecular mechanism of resveratrol in promoting wound healing and its administration methods in wound treatment were reviewed to provide ideas for the redevelopment of resveratrol.

Engineering tumor-colonizing E. coli Nissle 1917 for detection and treatment of colorectal neoplasia.

Bioengineered probiotics enable new opportunities to improve colorectal cancer (CRC) screening, prevention and treatment. Here, first, we demonstrate selective colonization of colorectal adenomas after oral delivery of probiotic E. coli Nissle 1917 (EcN) to a genetically-engineered murine model of CRC predisposition and orthotopic models of CRC. We next undertake an interventional, double-blind, dual-centre, prospective clinical trial, in which CRC patients take either placebo or EcN for two weeks prior to resection of neoplastic and adjacent normal colorectal tissue (ACTRN12619000210178). We detect enrichment of EcN in tumor samples over normal tissue from probiotic-treated patients (primary outcome of the trial). Next, we develop early CRC intervention strategies. To detect lesions, we engineer EcN to produce a small molecule, salicylate. Oral delivery of this strain results in increased levels of salicylate in the urine of adenoma-bearing mice, in comparison to healthy controls. To assess therapeutic potential, we engineer EcN to locally release a cytokine, GM-CSF, and blocking nanobodies against PD-L1 and CTLA-4 at the neoplastic site, and demonstrate that oral delivery of this strain reduces adenoma burden by ~50%. Together, these results support the use of EcN as an orally-deliverable platform to detect disease and treat CRC through the production of screening and therapeutic molecules.

[Long-term efficacy of balloon-assisted endplate augmentation combined with transforaminal pedicle screw fixation in the treatment of thoracolumbar burst fractures].

Objectives: To investigate the long-term efficacy of balloon assisted endplate reduction with vertebral augmentation combined with pedicle screw fixation in the treatment of thoracolumbar burst fractures, and to compare the clinical efficacy of calcium sulfate cement (CSC) and calcium phosphate cement(CPC). Methods: This study is a retrospective cohort study.The clinical data of 39 patients with thoracolumbar burst fractures admitted to Hefei Hospital Affiliated to Anhui Medical University from November 2013 to December 2017 were retrospectively analyzed.All patients were treated with pedicle screw reduction and fixation of the injured vertebra,balloon-assisted reduction of the collapsed endplate of the injured vertebra,and artificial bone vertebral body augmentation,and the follow-up time was >5 years.There were 24 males and 15 females,aged (42.9±13.3) years (range: 29 to 56 years).According to the Frankel spinal nerve dysfunction grading standard, there were 4 cases of grade C, 7 cases of grade D and 28 cases of grade E. There were 21 cases of CSC augmentation(CSC group) and 18 cases of CPC augmentation (CPC group). X-ray and CT were performed at 1 week, 1-, 2-, 5-year after surgery and at the last follow-up, and the imaging indicators were measured, including the injured vertebra anterior edge height ratio,the injured vertebra middle height ratio,the injured vertebra wedge angle,and the sagittal plane Cobb angle. The pain visual analogue scale (VAS) and the Oswestry disability index (ODI) was used for functional evaluation, nervous function was evaluated according to the Frankel spinal nerve dysfunction grading standard.Independent sample t test was used for inter-group comparison, and paired sample t test and repeated measure ANOVA were used for intra-group comparison. Results: All operative procedures were successfully completed, no spinal nerve function damage occurred. The postoperative imaging indexes of the patients were significantly improved compared with those before surgery (all P<0.01). The follow-up time of patients was (6.7±2.8)years (range: 5 to 9 years). Among the 11 patients with symptoms of neurological impairment before surgery, 9 patients completely recovered at the last follow-up, and 2 patients recovered from Frankel grade C to D. There were no significant differences in imaging indexes between the first week after surgery and the last follow-up in the CPC group (all P>0.05), while there were significant differences in imaging indexes between the CSC group and the last follow-up (all P<0.05). CPC group was superior to CSC group in frontal height ratio, middle height ratio, wedge angle variation and sagittal Cobb angle correction loss at 2 year, 5 year after surgery and the last follow-up, with statistical significance (all P<0.05). At the last follow-up, there were no differences in VAS and ODI between the two groups (all P>0.05). After absorption of CSC in the filling area, a hardened zone was formed around the area, and the central cavity remained without bone tissue filling. CPC absorption was very slow, and the CPC group was still filled satisfactorily at the last follow-up. Conclusions: Balloon assisted endplate reduction and vertebral augmentation combined with pedicle screw fixation through the injured vertebra have good long-term efficacy in the treatment of thoracolumbar burst fractures. Compared with CSC, CPC vertebral augmentation can better maintain the shape and spinal sequence of the injured vertebra in the long term, and can effectively reduce the collapse of the space above the injured vertebra.

Multi-targeted therapeutic effects of Sankudiwan (SKDW) in myocardial ischemia-reperfusion injury: a comprehensive study.

OBJECTIVE: This study aimed to investigate the therapeutic effects and underlying mechanisms of Sankudiwan (SKDW) on myocardial ischemia-reperfusion injury (MIRI) in a rat model. MATERIALS AND METHODS: Rats were subjected to MIRI and treated with varying doses of SKDW. The myocardial infarct size, cardiac function, histological changes, apoptosis, and inflammation were assessed using TTC staining, echocardiography, Hematoxylin and Eosin (HE) staining, TUNEL staining, and ELISA assays. We further explored SKDW's influence on cardiomyocyte mitochondria and inflammatory factor expression. Moreover, oxidative stress-related parameters and differentially expressed genes were analyzed using bioinformatics approaches. RESULTS: SKDW significantly reduced myocardial infarct size and improved cardiac function, demonstrating a dose-dependent therapeutic potential. It ameliorated myocardial tissue damage at the histological level, inhibited cardiomyocyte apoptosis, and mitigated inflammatory response. SKDW also enhanced mitochondrial energy metabolism and suppressed the levels of oxidative stress markers. Bioinformatics analysis identified key differentially expressed genes (DEGs), including cbln1, Tgm1, Trh, and Ccl27, possibly mediating the therapeutic effects of SKDW. CONCLUSIONS: SKDW exerts its therapeutic effects on MIRI through the modulation of several genes and pathways related to inflammation, apoptosis, mitochondrial function, and oxidative stress. Our findings provide a scientific basis for the clinical application of SKDW in the treatment of MIRI.

Loss of Grem1-lineage chondrogenic progenitor cells causes osteoarthritis.

Osteoarthritis (OA) is characterised by an irreversible degeneration of articular cartilage. Here we show that the BMP-antagonist Gremlin 1 (Grem1) marks a bipotent chondrogenic and osteogenic progenitor cell population within the articular surface. Notably, these progenitors are depleted by injury-induced OA and increasing age. OA is also caused by ablation of Grem1 cells in mice. Transcriptomic and functional analysis in mice found that articular surface Grem1-lineage cells are dependent on Foxo1 and ablation of Foxo1 in Grem1-lineage cells caused OA. FGFR3 signalling was confirmed as a promising therapeutic pathway by administration of pathway activator, FGF18, resulting in Grem1-lineage chondrocyte progenitor cell proliferation, increased cartilage thickness and reduced OA. These findings suggest that OA, in part, is caused by mechanical, developmental or age-related attrition of Grem1 expressing articular cartilage progenitor cells. These cells, and the FGFR3 signalling pathway that sustains them, may be effective future targets for biological management of OA.

[Intervention effect of apocynin on silicosis induced by silica in rats].

Objective: To investigate the intervention effect and its mechanism of apocynin, an inhibitor of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) on silicosis induced by silica (SiO(2)) in rats. Methods: In October 2021, 24 SPF SD male rats were divided into control group, silicosis model group and apocynin intervention group according to random number table method, with 8 rats in each group. SiO(2) was exposed by one-time intratracheal instillation. The rats in the apocynin intervention group were intraperitoneally injected with apocynin 50 mg/kg, 3 times a week, on the second day after treatment. The rats were sacrificed 28 days later, and lung coefficients were calculated after lung tissues were weighed. Hematoxylin-eosin staining and Masson staining were used to observe the lung histopathological changes in each group, respectively. The levels of NOX, reactive oxygen species (ROS), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) in lung tissue were detected. The expressions of interleukin-1 beta (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were determined by Enzyme-Linked Immunosorbent Assay (ELISA). The level of hydroxyproline (HYP) was detected by alkaline hydrolysate. The expressions of transforming growth factor beta 1 (TGF-ß1), E-cadherin (E-cad) and α-smooth muscle actin (α-SMA) in lung tissue were detected by Western blotting. Results: Compared with the control group, the body weight of silicosis model group was decreased, the lung tissue showed obvious inflammatory infiltration and fibrosis, and the levels of lung coefficient, IL-1ß, IL-6, TNF-α and TGF-ß1 were significantly increased (P<0.05). Compared with the silicosis model group, the lung tissue injury in the apocynin intervention group was significantly improved, the lung coefficient, NOX, ROS, MDA, IL-1ß, IL-6, TNF-α and TGF-ß1 levels were decreased, and the activity of GSH-Px was increased (P<0.05). Compared with the silicosis model group, the expressions of HYP and α-SMA were decreased and the level of E-cad was increased in the apocynin intervention group (P<0.05) . Conclusion: Apocynin may alleviate SiO(2)-induced fibrosis in silicosis rats by reducing oxidative stress, the release of inflammatory factors and inhibiting the process of epithelial-mesenchymal transition.

[The value of aspirin challenge tests in the diagnosis of non-steroidal anti-inflammatory drugs-exacerbated respiratory disease].

Objective: To investigate the value of aspirin challenge tests in the diagnosis of non-steroidal anti-inflammatory drugs-exacerbated respiratory disease (NERD). Methods: Fifty patients (22 males and 28 females; aged 16-61 years) who were diagnosed with chronic rhinosinusitis with nasal polyps (CRSwNP) with/without asthma, and underwent NERD standardized diagnosis in the Allergy Centre of West China Hospital, Sichuan University from December 2021 to November 2022 were included in the study. The first step was asking about the history of exacerbation respiratory symptoms after intake of any non-steroidal anti-inflammatory drug, including aspirin; the second step was performing intranasal aspirin challenge (IAC); and the third step was performing oral aspirin challenge (OAC). The diagnosis of NERD was made if any of the above steps was positive, and the subsequent steps were not performed, otherwise the diagnosis was made to OAC. If OAC was negative, the diagnosis was non-NERD. All patients completed the sino-nasal outcome test 22 (SNOT 22) score, Lund-Kennedy score by nasal endoscopic, allergen skin prick test, blood routine and serum total IgE test. SPSS version 20.0 was used for statistical analysis. Results: The diagnosis of NRED was confirmed in 27 patients (27/50, 54%). Seven (7/50, 14%) of them were diagnosed by clinical history and 20 (20/50, 40%) were diagnosed by aspirin challenge tests, of which 17 (17/20, 85%) were positive to IAC and 3 (3/20, 15%) to OAC. Of the 43 patients who underwent IAC testing, only 2 (2/43, 5%) developed asthma attacks during challenge. Comparing the clinical characteristics of patients in NERD and non-NERD group, there were significant differences between the two groups in gender (P=0.001), hyposmia (P=0.003), history of repeated CRSwNP surgeries (P=0.028), comorbid asthma (P=0.013), SNOT-22 score (P=0.004) and the percentage of peripheral blood eosinophil (P=0.043). Conclusions: Patients may be underdiagnosed if the diagnosis of NERD is made only by medical history, and it is necessary to carry out aspirin challenge tests. IAC is an important means to diagnose NERD with high accuracy and good safety. However, If IAC is negative, further OAC is required.

[Distribution and reference intervals of daytime intraocular pressure in the eye health screening population of Handan].

Objective: To describe the distribution and establish reference intervals (RI) of daytime intraocular pressure (IOP) in the eye health screening population of Handan. Methods: This cross-sectional study included subjects who participated in eye health screening at the Physical Examination Center of Handan First Hospital from May 2021 to June 2022. A complete general and ocular examination was performed, including measurements of visual acuity and IOP (using Goldmann tonometry), slit lamp microscopy, fundus photography, and anterior and posterior segment optical coherence tomography. Subjects with factors that could cause significant changes in IOP or affect the accuracy of IOP measurement, or with an inability to measure IOP were excluded. Simple random sampling was used to select participants, who were grouped by gender and age (18 to <30, 30 to <40, 40 to <50, 50 to <60, 60 to <70, and ≥70 years). Central corneal thickness and IOP at 8 to 11 o'clock in one eye of each participant were recorded. The independent sample t test and ANOVA were used for statistical analysis, and the RI of IOP values was calculated by x¯±1.96s. Results: A total of 9 310 subjects had their IOP measured, and 3 491 participants (3 491 eyes) were randomly selected from 7 886 healthy subjects. The age of the participants was (47.74±14.47) years old, ranging from 18 to 90 years old. There were 1 694 males and 1 797 females. The central corneal thickness of all participants was (525.56±49.39) µm. The daytime IOP of all participants was (15.40±2.54) mmHg (1 mmHg=0.133 kPa), and the RI was 10.42 to 20.39 mmHg. The IOP was (15.49±2.58) mmHg for males and (15.29±2.49) mmHg for females, and the gender difference was statistically significant (P<0.05). The RI of daytime IOP values was 10.43 to 20.54 mmHg for males and 10.41 to 20.18 mmHg for females. There were significant differences in daytime IOP [(15.13±2.58), (15.33±2.53), (15.49±2.50), (15.53±2.55), (15.39±2.62), and (15.28±2.52) mmHg] among 6 age groups (P<0.05). Conclusions: The distribution of daytime IOP in different gender and age groups in the eye health screening population of Handan and the RIs derived from the distribution were roughly the same as the international normal IOP RI (10 to 21 mmHg). It is recommended to refer to the RI of daytime IOP values of different genders and ages for clinical decision.

Engineered bacteria detect tumor DNA.

Synthetic biology has developed sophisticated cellular biosensors to detect and respond to human disease. However, biosensors have not yet been engineered to detect specific extracellular DNA sequences and mutations. Here, we engineered naturally competent Acinetobacter baylyi to detect donor DNA from the genomes of colorectal cancer (CRC) cells, organoids, and tumors. We characterized the functionality of the biosensors in vitro with coculture assays and then validated them in vivo with sensor bacteria delivered to mice harboring colorectal tumors. We observed horizontal gene transfer from the tumor to the sensor bacteria in our mouse model of CRC. This cellular assay for targeted, CRISPR-discriminated horizontal gene transfer (CATCH) enables the biodetection of specific cell-free DNA.

Baicalin alleviates silica-induced lung inflammation and fibrosis by inhibiting TLR4/NF-?B pathway in rats.

Silicosis is an occupational lung disease caused by inhaling silica dust. The disease is characterized by early lung inflammation and late irreversible pulmonary fibrosis. Here we report the effect of Baicalin, a main flavonoid compound from the roots of Chinese herbal medicine Huang Qin on silicosis in a rat model. Results showed Baicalin (50 or 100 mg/kg/day) can mitigate the silica-induced lung inflammation and reduce the harm of alveolar structure and the blue region of collagen fibers in rat lung at 28 days after administration. At the same time, Baicalin also diminished the level of interleukin-1beta (IL-1beta, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta1 (TGF-beta1) in lung tissues. The protein expression of collagen I (Col-1), alpha-smooth muscle actin (alpha-SMA) and vimentin were down-regulated while E-cadherin (E-cad) was increased in Baicalin-treated rats. In addition, the Toll Like Receptor 4 (TLR4)/ nuclear factor kappaB (NF-kappaB) pathway was enabled at 28 days after silica infusion, and the treatment of Baicalin diminished the expression of TLR4 and NF-?B in the lungs of rat with silicosis. These results suggested that Baicalin inhibited the pulmonary inflammatory and fibrosis in a rat model of silicosis, which could be attributed to inhibition of the TLR4/NF-kappaB pathway.

Colorectal cancer detection and treatment with engineered probiotics.

Bioengineered probiotics enable new opportunities to improve colorectal cancer (CRC) screening, prevention and treatment strategies. Here, we demonstrate the phenomenon of selective, long-term colonization of colorectal adenomas after oral delivery of probiotic E. coli Nissle 1917 (EcN) to a genetically-engineered murine model of CRC predisposition. We show that, after oral administration, adenomas can be monitored over time by recovering EcN from stool. We also demonstrate specific colonization of EcN to solitary neoplastic lesions in an orthotopic murine model of CRC. We then exploit this neoplasia-homing property of EcN to develop early CRC intervention strategies. To detect lesions, we engineer EcN to produce a small molecule, salicylate, and demonstrate that oral delivery of this strain results in significantly increased levels of salicylate in the urine of adenoma-bearing mice, in comparison to healthy controls. We also assess EcN engineered to locally release immunotherapeutics at the neoplastic site. Oral delivery to mice bearing adenomas, reduced adenoma burden by ∻50%, with notable differences in the spatial distribution of T cell populations within diseased and healthy intestinal tissue, suggesting local induction of robust anti-tumor immunity. Together, these results support the use of EcN as an orally-delivered platform to detect disease and treat CRC through its production of screening and therapeutic molecules.

Loss of Grem1-articular cartilage progenitor cells causes osteoarthritis.

Osteoarthritis (OA), which carries an enormous disease burden across the world, is characterised by irreversible degeneration of articular cartilage (AC), and subsequently bone. The cellular cause of OA is unknown. Here, using lineage tracing in mice, we show that the BMP-antagonist Gremlin 1 (Grem1) marks a novel chondrogenic progenitor (CP) cell population in the articular surface that generates joint cartilage and subchondral bone during development and adulthood. Notably, this CP population is depleted in injury-induced OA, and with age. OA is also induced by toxin-mediated ablation of Grem1 CP cells in young mice. Transcriptomic analysis and functional modelling in mice revealed articular surface Grem1-lineage cells are dependent on Foxo1; ablation of Foxo1 in Grem1-lineage cells led to early OA. This analysis identified FGFR3 signalling as a therapeutic target, and injection of its activator, FGF18, caused proliferation of Grem1-lineage CP cells, increased cartilage thickness, and reduced OA pathology. We propose that OA arises from the loss of CP cells at the articular surface secondary to an imbalance in progenitor cell homeostasis and present a new progenitor population as a locus for OA therapy.

Two QSAR models for predicting the toxicity of chemicals towards Tetrahymena pyriformis based on topological-norm descriptors and spatial-norm descriptors.

Quantitative structure-activity relationship (QSAR) is important for safe, rapid and effective risk assessment of chemicals. In this study, two QSAR models were established with 1230 chemicals to predict toxicity towards Tetrahymena pyriformis using multiple linear regression (MLR) method. The topological(T)-QSAR model was developed by using topological-norm descriptors generated from the topological structure, and the spatial(S)-QSAR model were built with spatial-norm descriptors obtained from the three-dimensional structure of molecules and topological-norm descriptors. The r2training and r2test are 0.8304 and 0.8338 for the T-QSAR model, and 0.8485 and 0.8585 for the S-QSAR model, which means that T-QSAR model and S-QSAR model can be used to predict toxicity quickly and accurately. In addition, we also conducted validation on the developed models. Satisfying validation results and statistical parameters demonstrated that QSAR models based on the topological-norm descriptors and spatial-norm descriptors proposed in this paper could be further utilized to estimate the toxicity of chemicals towards Tetrahymena pyriformis.

[Standardized diagnosis results of suspected local anesthetics allergy].

To review and investigate the diagnosis results of local anesthetics (LA) allergy and improve the understanding of LA allergy in clinician. From March 2017 to February 2022, a total of 24 patients were investigated in Allergy Center of West China Hospital,Sichuan University on suspicion of LA allergy. Clinical data and results of skin tests and drug provocation tests (DPT) with the suspected drugs were retrospectively evaluated. The value of standardized diagnostic protocol in the LA allergy were analyzed. The results showed that 24 patients (3 men/21 women) were included with age range from 20 to 74 years. Three cases (12.5%) were positive in previous LA skin tests and proved to be tolerated through standardized tests. Twenty-one patients were initially diagnosed as "LA allergy" because of adverse reactions after previous use of LA, including 20 cases of immediate-type reaction and 1 case of delayed-type reaction. Three cases were considered LA allergy through standardized diagnosis approaches, including skin tests and DPT. One patient was diagnosed with anaphylaxis caused by chlorhexidine. Of the remaining 17 patients, 7 were considered as psychosomatic reactions (29.1%), 3 of sympathetic nervous system conditions (12.5%), 1 of spontaneous urticaria (4.2%), 2 of vasovagal syncope (8.3%), drug side effects (8.3%), skin irritation (8.3%), respectively. In conclusion, true allergic reactions to LA are rare. Through standardized skin tests and DPT, allergy can be ruled out in the vast majority of patients who complain of "LA allergy". For patients who are highly suspected of LA inducing anaphylaxis, other local anesthetics that can be used as safe alternatives should be determined by diagnostic tests according to future needs.

A novel small molecule inhibitor of human Drp1.

Mitochondrial dynamin-related protein 1 (Drp1) is a large GTPase regulator of mitochondrial dynamics and is known to play an important role in numerous pathophysiological processes. Despite being the most widely used Drp1 inhibitor, the specificity of Mdivi-1 towards human Drp1 has not been definitively proven and there have been numerous issues reported with its use including off-target effects. In our hands Mdivi-1 showed varying binding affinities toward human Drp1, potentially impacted by compound aggregation. Herein, we sought to identify a novel small molecule inhibitor of Drp1. From an initial virtual screening, we identified DRP1i27 as a compound which directly bound to the human isoform 3 of Drp1 via surface plasmon resonance and microscale thermophoresis. Importantly, DRP1i27 was found to have a dose-dependent increase in the cellular networks of fused mitochondria but had no effect in Drp1 knock-out cells. Further analogues of this compound were identified and screened, though none displayed greater affinity to human Drp1 isoform 3 than DRP1i27. To date, this is the first small molecule inhibitor shown to directly bind to human Drp1.

[Study of risk factors of postherpetic neuralgia].

Objective: To analyze the clinical features and risk factors of herpes zoster and the risk factors of postherpetic neuralgia (PHN). Methods: A total of 2 840 patients diagnosed with herpes zoster in Peking University People's Hospital from January 2021 to April 2022 were included. The patients with herpes zoster were aged (59±16), and of which 1 314 (46.3%) patients were male. The patients were divided into PHN group and non-PHN group according to whether the patients with herpes zoster developed PHN. And there were 442 (15.6%) patients developed PHN aged (68±12), and of which 189 (42.8%) were male. The information and medical history of PHN group and non-PHN group were collected. The information of the use of glucocorticoids, immunosuppressive agents, biological agents and targeted medicine within 2 months before herpes zoster occurred, history of surgery within 6 months before herpes zoster occurred, and the duration of PHN were collected. Logistic regression analysis was used to analyze the risk factors of PHN. Results: Out of 2 840 patients, 2 056 (72.4%) with herpes zoster aged 50 years and above. Intercostal nerves was mostly involved in patients with herpes zoster, with a total of 1 532(53.9%). Hypertension (465 cases, 16.4%) accounted for the highest number of patients with chronic diseases, followed by diabetes (337 cases, 11.9%) and coronary heart disease (283 cases, 10.0%). Rheumatoid arthritis (41 cases, 1.4%) accounted for the highest number of patients with connective tissue diseases, followed by Sjogren's syndrome (31 cases, 1.1%), systemic lupus erythematosus (28 cases, 1.0%). Logistic regression analysis showed that age≥50 years old (OR: 4.581; 95%CI: 3.131-6.705),lesion on the upper limb and shoulder (OR: 1.858; 95%CI: 1.129-3.059), hypertension (OR: 1.963; 95%CI: 1.513-2.546) and immunosuppressive treatments (OR: 2.170; 95%CI: 1.254-3.753) were independent risk factors for PHN (all P<0.05). Conclusions: Herpes zoster mostly occurs in people aged 50 and above, and mainly affected intercostal nerves. The most common complications are hypertension and rheumatoid arthritis. Age≥50, lesion on upper limbs and shoulders, hypertension, and immunosuppressive treatments may be independent risk factors of PHN.

Structural Analysis of the Complex of Human Transthyretin with 3',5'-Dichlorophenylanthranilic Acid at 1.5 Å Resolution.

Human transthyretin (hTTR) can form amyloid deposits that accumulate in nerves and organs, disrupting cellular function. Molecules such as tafamidis that bind to and stabilize the TTR tetramer can reduce such amyloid formation. Here, we studied the interaction of VCP-6 (2-((3,5-dichlorophenyl)amino)benzoic acid) with hTTR. VCP-6 binds to hTTR with 5 times the affinity of the cognate ligand, thyroxine (T4). The structure of the hTTR:VCP-6 complex was determined by X-ray crystallography at 1.52 Šresolution. VCP-6 binds deeper in the binding channel than T4 with the 3',5'-dichlorophenyl ring binding in the 'forward' mode towards the channel centre. The dichlorophenyl ring lies along the 2-fold axis coincident with the channel centre, while the 2-carboxylatephenylamine ring of VCP-6 is symmetrically displaced from the 2-fold axis, allowing the 2-carboxylate group to form a tight intermolecular hydrogen bond with Nζ of Lys15 and an intramolecular hydrogen bond with the amine of VCP-6, stabilizing its conformation and explaining the greater affinity of VCP-6 compared to T4. This arrangement maintains optimal halogen bonding interactions in the binding sites, via chlorine atoms rather than iodine of the thyroid hormone, thereby explaining why the dichloro substitution pattern is a stronger binder than either the diiodo or dibromo analogues.