Molecular Chain Rearrangement-Induced In Situ Formation of Nanofibers for Improving the Strength and Toughness of Hydrogels.

Although poly(vinyl alcohol) (PVA) hydrogel has high elasticity and is suitable for cartilage tissue engineering, it is difficult to have both high strength and toughness. In this study, a simple and universal strategy is proposed to prepare strong and tough PVA hydrogels by in situ forming nanofibers on the original network structure induced by a molecular chain rearrangement. Quenching-tempering alteratively in ethanol and water several times is carried out to strengthen PVA hydrogels (PVA-Etn hydrogels) due to the advantages of noncovalent bonds in adjustability and reversibility. The results show that, after three quenching-tempering cycles, PVA-Et3 hydrogel with water content up to 79 wt % shows comprehensive improved mechanical properties. The compression modulus, tensile modulus, fracture strength, tensile strain, and tear energy of the PVA-Et3 hydrogel are 270, 250, 260, 130, and 180% of the initial PVA hydrogel, respectively. The improved mechanical properties of the PVA-Et3 hydrogel are attributed to the strong cross-linked PVA chains and hydrogen bond-reinforced nanofibers. This study not only provides a simple and efficient solution for the preparation of strong and tough polymer scaffolds in tissue engineering but also provides new insights for understanding the mechanism of improving the mechanical properties of polymer hydrogels by adjusting the molecular structure.

Distribution of virulence genes and antimicrobial resistance of Escherichia coli isolated from hospitalized neonates: A multi-center study across China.

Background: Escherichia coli is the most common gram-negative pathogen to cause neonatal infections. Contemporary virulence characterization and antimicrobial resistance (AMR) data of neonatal E. coli isolates in China are limited. Methods: A total of 159 E. coli strains isolated from neonates were collected and classified into invasive and non-invasive infection groups, according to their site of origin. The presence of virulence genes was determined using polymerase chain reaction (PCR). All the strains were subjected to antimicrobial susceptibility testing using the broth dilution method. Results: The top three virulence genes with the highest detection rates were fimH (90.6 %), iutA (88.7 %), and kspMT II (88.1 %). The prevalences of fyuA (p = 0.023), kpsMT K1 (p = 0.019), ibeA (p < 0.001), and iroN (p = 0.027) were significantly higher in the invasive infection group than in the non-invasive infection group. Resistance to ceftazixime, sulfamethoxazole/trimethoprim, and ciprofloxacin was 75.5 %, 65.4 %, and 48.4 %, respectively. Lower rates of resistance to ceftazidime (p = 0.022), cefepime (p = 0.005), ticarcillin/clavulanic acid (p = 0.020) and aztreonam (p = 0.001) were observed in the invasive infection group compared to the non-invasive infection group. The number of virulence genes carried by E. coli was positively correlated with the number of antibiotics to which the isolates were resistant (r = 0.71, p = 0.016), and a specific virulence gene was associated with resistance to various species of antibiotics. Conclusions: Neonatal E. coli isolates carried multiple virulence genes and were highly resistant to antibiotics. Further studies are needed to understand the molecular mechanisms underlying the association between virulence and AMR.

Cancellation of the more complicated ophthalmic inpatient surgeries in a tertiary general hospital: a 10-year retrospective study.

Background: Although ophthalmic ambulatory surgeries are less costly and may enhance the more efficient utilization of hospital resources, inpatient surgeries were preferable alternatives for patients with complicated eye diseases or poor general health. However, the incidence, causes, and related factors of ophthalmic inpatient surgery cancellation remained largely unknown. Methods: The electronic medical records of ophthalmic inpatient surgeries between January 2012 and December 2022 was retrospectively reviewed. Cancellation-related factors were explored using multivariate logistic regression analysis and the reasons of cancellation were also evaluated. Results: In total, 820 cancelled surgeries and 42,073 performed surgeries were included, with a cancellation rate of 1.9%. Any other ocular comorbidities were risk factors for cancellation (odds ratio (OR) 1.872, 95% confidence intervals (CI) 1.504-2.331; p < 0.001), while older age (OR 0.990, 95% CI 0.986-0.995; p < 0.001), local residence (OR 0.809, 95% CI 0.692-0.947; p = 0.008), any systemic comorbidities (OR 0.740, 95% CI 0.616-0.889; p = 0.001), and previous history of surgeries (OR 0.403, 95% CI 0.341-0.476; p < 0.001) were negatively associated with surgery cancellation. The top two categorical cancellation reasons were medical factors (508, 62.0%) and patient-related factors (285, 34.8%). "Patient/family refused surgery" (127, 15.5%), "acute conjunctivitis or uveitis relapse" (103, 12.6%), and "ocular condition improved and procedure no longer indicated" (71, 8.7%) were the three most common single cancellation reasons. Conclusion: Any other ocular comorbidities, younger age, no systemic comorbidities, non-local residence, and no past surgical history were related factors for ophthalmic inpatient surgery cancellation. The majority of cancellations were due to patient-related or medical factors. Great importance should be attached to the cancellation of the more complicated inpatient surgeries and further efforts are warranted to explore how to reduce cancellation.

O-PRESS: Boosting OCT axial resolution with Prior guidance, Recurrence, and Equivariant Self-Supervision.

Optical coherence tomography (OCT) is a noninvasive technology that enables real-time imaging of tissue microanatomies. The axial resolution of OCT is intrinsically constrained by the spectral bandwidth of the employed light source while maintaining a fixed center wavelength for a specific application. Physically extending this bandwidth faces strong limitations and requires a substantial cost. We present a novel computational approach, called as O-PRESS, for boosting the axial resolution of OCT with Prior guidance, a Recurrent mechanism, and Equivariant Self-Supervision. Diverging from conventional deconvolution methods that rely on physical models or data-driven techniques, our method seamlessly integrates OCT modeling and deep learning, enabling us to achieve real-time axial-resolution enhancement exclusively from measurements without a need for paired images. Our approach solves two primary tasks of resolution enhancement and noise reduction with one treatment. Both tasks are executed in a self-supervised manner, with equivariance imaging and free space priors guiding their respective processes. Experimental evaluations, encompassing both quantitative metrics and visual assessments, consistently verify the efficacy and superiority of our approach, which exhibits performance on par with fully supervised methods. Importantly, the robustness of our model is affirmed, showcasing its dual capability to enhance axial resolution while concurrently improving the signal-to-noise ratio.

Photo-crosslinking methacrylated-amylopectin/polyacrylamide hydrogels loading curcumin for applications as degradable, injectable, and antibacterial wound dressings.

The preparation of biodegradable and antibacterial hydrogels has important clinical value. In this work, a novel strategy has been developed to prepare degradable hydrogel dressings without chemical crosslinking agent using methacrylate anhydride (MA)-modified amylopectin (APMA) and polyacrylamide (PAM). After introducing CC bonds, APMA/PAM hydrogels can be formed under light irradiation. This strategy improves the gelling ability of AP and degradation properties of the hydrogel by avoiding the addition of crosslinking agent. The degradation rate of APMA/PAM hydrogel is 74.04 ± 0.69 % within 12 weeks, while that of APMA/PAM hydrogel containing crosslinking agent is only 38.5 ± 0.1 %. The APMA/PAM hydrogel loading curcumin (Cur) (APMA/PAM-Cur) exhibits high antibacterial efficiency of 98.29 ± 0.41 % and 97.18 ± 0.81 % against S. aureus and E. coli, respectively, with light irradiation. Animal experiments show that the APMA/PAM-Cur hydrogel reduces the infiltration of inflammatory factors, increases the density of collagen, and makes the newly formed granulation tissue thicker and tighter. This study not only proves the promising potential of the APMA/PAM-Cur hydrogel as degradable and antibacterial wound dressing for clinical treatment, but also provides a new strategy for developing low-cost, degradable, and antibacterial wound dressings and reducing antibiotic abuse and environmental pollution caused by medical waste.

Development and validation of optical coherence tomography (OCT) and OCT angiography prediction model for short-term vitreous haemorrhage secondary to polypoidal choroidal vasculopathy.

AIMS: To construct and validate an optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) image model for predicting the occurrence of short-term vitreous haemorrhage (VH) in polypoidal choroidal vasculopathy (PCV) patients. METHODS: We retrospectively collected clinical and imaging information from patients diagnosed with PCV at Peking Union Medical College Hospital, Beijing, China, between January 2015 and October 2022. Six different screening strategies, including univariate analysis, multivariate analysis, least absolute shrinkage and selection operator, stepwise logistic regression, random forest and clinical-data-only approach, were used to select variables and build models. The nomogram was constructed based on the model with the best area under the curve (AUC) and was evaluated using receiver operating characteristic curves, calibration curves, decision curve analysis and clinical impact curves. RESULTS: A total of 147 PCV patients were included and randomly divided into a training set (103 patients) and a validation set (44 patients), with an average follow-up time of 17.56±14.99 months. The optimal model that achieved higher AUC in both training and validation sets incorporated seven significant variables identified through univariate analysis: male [OR=2.76, p=0.022], central macular thickness [OR=1.003, p=0.002], the presence of haemorrhagic pigment epithelial detachment (HPED) [OR=6.99, p<0.001], the height of HPED [OR=1.002, p<0.001], the area of HPED [OR=1.16, p<0.001], the presence of multiple PEDs [OR=2.94, p=0.016] and the presence of subretinal haemorrhage [OR=3.11, p=0.011]. A predictive nomogram based on these variables yielded an AUC of 0.896 (95% CI 0.827 to 0.965) in the training set and 0.861 (95% CI 0.749 to 0.973) in the validation set, demonstrating good calibration and clinical usefulness. CONCLUSION: The proposed OCT/OCTA-based image nomogram, as a novel and non-invasive tool, achieved satisfactory prediction of VH secondary to PCV.

Ocular fundus changes and association with systemic conditions in systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease that affects multiple organs and systems. Ocular involvement is estimated to manifest in one-third of individuals with SLE, of which lupus retinopathy and choroidopathy represent the severe subtype accompanied by vision impairment. Advancements in multimodal ophthalmic imaging have allowed ophthalmologists to reveal subclinical microvascular and structural changes in fundus of patients with SLE without ocular manifestations. Both ocular manifestations and subclinical fundus damage have been shown to correlate with SLE disease activity and, in some patients, even precede other systemic injuries as the first presentation of SLE. Moreover, ocular fundus might serve as a window into the state of systemic vasculitis in patients with SLE. Given the similarities of the anatomy, physiological and pathological processes shared among ocular fundus, and other vital organ damage in SLE, such as kidney and brain, it is assumed that ocular fundus involvement has implications in the diagnosis and evaluation of other systemic impairments. Therefore, evaluating the fundus characteristics of patients with SLE not only contributes to the early diagnosis and intervention of potential vision damage, but also holds considerate significance for the evaluation of SLE vasculitis state and prediction of other systemic injuries.

The Mitogenomic Landscape of Hexacorallia Corals: Insight into Their Slow Evolution.

The utility of the mitochondrial genomes (mitogenomes) in analyzing the evolutionary history of animals has been proven. Five deep-sea corals (Bathypathes sp.1, Bathypathes sp.2, Schizopathidae 1, Trissopathes sp., and Leiopathes sp.) were collected in the South China Sea (SCS). Initially, the structures and collinearity of the five deep-sea coral mitogenomes were analyzed. The gene arrangements in the five deep-sea coral mitogenomes were similar to those in the order Antipatharia, which evidenced their conservation throughout evolutionary history. Additionally, to elucidate the slow evolutionary rates in Hexacorallia mitogenomes, we conducted comprehensive analyses, including examining phylogenetic relationships, performing average nucleotide identity (ANI) analysis, and assessing GC-skew dissimilarity combining five deep-sea coral mitogenomes and 522 reference Hexacorallia mitogenomes. Phylogenetic analysis using 13 conserved proteins revealed that species clustered together at the order level, and they exhibited interspersed distributions at the family level. The ANI results revealed that species had significant similarities (identity > 85%) within the same order, while species from different orders showed notable differences (identity < 80%). The investigation of the Hexacorallia mitogenomes also highlighted that the GC-skew dissimilarity was highly significant at the order level, but not as pronounced at the family level. These results might be attributed to the slow evolution rate of Hexacorallia mitogenomes and provide evidence of mitogenomic diversity. Furthermore, divergence time analysis revealed older divergence times assessed via mitogenomes compared with nuclear data, shedding light on significant evolutionary events shaping distinct orders within Hexacorallia corals. Those findings provide new insights into understanding the slow evolutionary rates of deep-sea corals in all lineages of Hexacorallia using their mitogenomes.

Real-time fluorescent multiple cross displacement amplification for rapid and sensitive Mycoplasma pneumoniae detection.

Mycoplasma pneumoniae is a significant pathogen responsible for community-acquired pneumonia, predominantly affecting children and adolescents. Here, we devised a rapid method for M. pneumoniae that combined multiple cross displacement amplification (MCDA) with real-time fluorescence technology. A set of ten primers, which were specifically designed for M. pneumoniae detection, were employed in a real-time fluorescence MCDA reaction. Of these, one primer incorporated a restriction endonuclease recognition sequence, a fluorophore, and a quencher, facilitating real-time fluorescence detection. The real-time (RT)-MCDA reactions were monitored in a simple real-time fluorescence instrument and conducted under optimised conditions (64°C for 40 min). The detection limit of the M. pneumoniae RT-MCDA assay for genomic DNA extracted from M. pneumoniae culture was down to 43 fg/µl. This assay accurately identified M. pneumoniae strains without cross-reacting with other bacteria. To validate its practical application, we tested the M. pneumoniae RT-MCDA assay using genomic DNA extracted from clinical samples. The assay's detection capability proved comparable with real-time PCR, MCDA-based biosensor detection, and visual inspection under blue light. The entire process, including rapid DNA extraction and real-time MCDA detection, was completed within 1 h. Overall, the M. pneumoniae RT-MCDA assay reported here is a simple and effective diagnostic tool for rapid M. pneumoniae detection, which holds significant potential for point-of-care testing and in resource-limited regions.

Comparison of three-dimensional heads-up system versus traditional microscopic system in medical education for vitreoretinal surgeries: a prospective study.

BACKGROUND: To compare the value and efficiency of the three-dimensional (3D) heads-up surgical system and traditional microscopic (TM) system in teaching and learning vitreoretinal surgeries. METHODS: Twenty ophthalmologists and scrub nurses were recruited as teachers, and 45 junior ophthalmology residents and trainee doctors, trainee nurses, and medical students were recruited as observers. Each teacher and observer were assigned to both a 3D-assisted and TM-assisted vitreoretinal surgery and then asked to complete satisfaction questionnaires for both surgical systems at the end of each surgery. RESULTS: The 3D heads-up surgical system was rated significantly higher in most of the subscales and overall satisfaction score by both teachers and observers (P < 0.05). However, ratings for instrument adjustment were significantly higher in the TM group compared to the 3D group for junior ophthalmology residents and trainee doctors (6.1 ± 1.7 vs. 8.8 ± 1.1, P < 0.001). CONCLUSIONS: The 3D heads-up surgical system has great didactical value in the medical education of vitreoretinal surgeries, but it is important to consider the specific needs of different learners when choosing between the two systems. TRIAL REGISTRATION: Not applicable.

Central and Peripheral Changes in Retinal Vein Occlusion and Fellow Eyes in Ultra-Widefield Optical Coherence Tomography Angiography.

Purpose: To explore the central and peripheral retinal and choroidal changes in retinal vein occlusion (RVO) and fellow eyes using ultra-widefield swept-source optical coherence tomography angiography (UWF-SS-OCTA). Methods: Fifteen ischemic central RVO (CRVO), 15 branch RVO (BRVO), and 15 age-matched healthy controls were prospectively recruited. Retinal and choroidal parameters, including retinal vessel flow density (VFD) and vessel linear density (VLD), choroidal vascularity volume (CVV), choroidal vascularity index (CVI), and VFD in the large and medium choroidal vessels (LMCV-VFD), were measured in the central and peripheral regions of the 24 × 20-mm UWF-SS-OCTA images. Results: Ischemic CRVO and BRVO eyes showed increased foveal avascular zone area, perimeter, and acircularity index (AI) compared to their fellow eyes and healthy control eyes, and RVO fellow eyes also had larger AI values than controls (P < 0.05). For ischemic CRVO and BRVO eyes versus control eyes, VFD, VLD, CVV, CVI, and LMCV-VFD decreased, but retinal thickness and volume in the superficial capillary plexus, deep capillary plexus, and whole retina increased (P < 0.05). Moreover, RVO fellow eyes also showed significantly decreased retinal VFD, LMCV-VFD, and CVI, as well as increased retinal thickness and volume, compared with control eyes (P < 0.05). Alterations were not consistent throughout the retina, as they involved only the peripheral or central regions in some cases. Conclusions: The affected and unaffected fellow eyes of RVO patients both demonstrated central and/or peripheral structural and vascular alterations in the retina and choroid. Because UWF-SS-OCTA enables visualization and evaluation of the vasculature outside the posterior pole, it presents a promising approach to more fully characterize vascular alterations in RVO.

Quantitative assessment of retinal vasculature changes in systemic lupus erythematosus using wide-field OCTA and the correlation with disease activity.

Purpose: To assess the retinal vasculature changes quantitatively using wide-field optical coherence tomography angiography (OCTA) in systemic lupus erythematosus (SLE), and explore its correlation with systemic clinical features. Design: Prospective, cross-sectional, observational study. Participants and controls: Patients with SLE who presented to the Ophthalmology Department of Peking Union Medical College Hospital from November 2022 to April 2023 were collected. The subjects were divided into retinopathy and without retinopathy groups. Age and gender-matched healthy subjects were selected as controls. Methods: Patients with SLE and control subjects were imaged with 24×20 mm OCTA scans centered on the fovea and 6×6 mm OCTA scans centered on the optic disc. The sub-layers of OCTA images were stratified by the built-in software of the device and then the retinal thickness and vessel density were measured automatically. The characteristics of retinal OCTA parameters of SLE and its correlation with systemic clinical indicators of patients without retinopathy were analyzed. Main outcome measures: OCTA parameters, visual acuity, intraocular pressure, and systemic clinical indicators of patients such as disease activity index, autoimmune antibodies, and inflammatory marker levels were collected. Results: A total of 102 SLE patients were included, 24 of which had retinopathy, and 78 had unaffected retina. Wide-field OCTA could effectively detect retinal vascular obstruction, non-perfusion area, and morphological abnormalities in patients with lupus retinopathy. SLE patients without retinopathy had significantly higher retinal superficial vessel density (SVD) in foveal (P=0.02), para-foveal temporal (P=0.01), nasal (P=0.01), peripheral foveal temporal (P=0.02), and inferior areas (P=0.02), as well as subregion temporal (P=0.01) and inferior areas (P=0.03) when compared with healthy controls (n=65 eyes from 65 participants). The area under curve (AUC) value of subregion inferior SVD combined parafoveal temporal SVD was up to 0.70. There was a significantly positive correlation between SVD and disease activity in SLE without retinopathy group. Patients with severe activity had the most significant increase in SVD. Conclusion: Wide-field OCTA can provide a relatively comprehensive assessment of the retinal vasculature in SLE. In the absence of pathological changes of the retina, the SVD was significantly increased and was positively correlated with the disease activity of SLE.

Systemic risk factors of retinopathy in patients with systemic lupus erythematosus.

OBJECTIVE: To investigate the risk factors of lupus retinopathy (LR) in patients with systemic lupus erythematosus (SLE). METHODS: This is a retrospective, cross-sectional study. LR patients admitted at Peking Union Medical College Hospital from June 2013 to April 2023 were reviewed. Age- and gender-matched SLE patients without retinopathy were selected as controls. Medical records including clinical manifestations, laboratory data and ophthalmic examination were collected. Univariate and multivariate logistic regression analyses were conducted. RESULTS: One hundred and twelve LR patients (198 eyes) were included, with 12 cases (14 eyes) presenting with retinal macrovascular obstruction, and 100 cases (184 eyes) only exhibiting microvasculopathy. Multivariate analysis indicated the presence of haemolytic anaemia, decreased haemoglobin (HGB) and higher relative percentage of neutrophils were independent risk factors for LR (p < 0.05). The first two were also risk factors for retinal microvasculopathy, whereas secondary antiphospholipid syndrome (APS) was for macrovascular obstruction. In male group, LR had significant associations with decreased HGB, no matter which types of retinopathy (p < 0.05). In female group, LR was significantly associated with haemolytic anaemia, presence of antiphospholipid antibodies, decreased white blood cells and relative high percentage of neutrophils. Specifically, haemolytic anaemia (p = 0.002) was significantly associated with retinal microvasculopathy, and APS (p = 0.003) was significantly associated with macrovasculature obstruction. CONCLUSION: LR was related to haemolytic anaemia, decreased HGB levels and higher percentage of neutrophils. Retinal microvasculopathy accounted for most cases and macrovasculature obstructions were rare. Male and female patients have distinct risk factors. Early ophthalmic screening is recommended especially for those with risk factors of LR.

Differences between young and elderly polypoidal choroidal vasculopathy patients with and without pachychoroid phenotypes.

PURPOSE: To investigate the distinct characteristics between young and elderly polypoidal choroidal vasculopathy (PCV) patients based on the pachy- or non-pachychoroid phenotypes. METHODS: PCV patients treated with intravitreal injections of Conbercept based on the 3 + PRN regimen from 27 centers of China PCV Research Alliance were included. Patients were categorized into the young and the elderly aged group based on the cut-off point determined using the Youden method according to the pachychoroid phenotypes. The characteristics of past medical history, lifestyle factors, fundus manifestations, and treatment response between the subgroups were analyzed. RESULTS: Three hundred eight eligible patients were included. Multivariate logistic regression showed a significant association between age and PCV subtype classification (OR = 0.921, P = 0.002). A cutoff age of 64.5 effectively distinguished between pachychoroid PCV and non-pachychoroid PCV (P < 0.001). Elderly PCV patients had a higher incidence of hypertension history (P = 0.044) but a lower incidence of diabetes history (P = 0.027). In terms of lifestyle, smoking history (P = 0.015) and staying up late (P = 0.004) were more significant in the young group of PCV patients. For clinical characteristics, the proportion of hemorrhagic PCV in the young group was significantly higher (P = 0.038), with a higher proportion of sharp-peaked PED (P = 0.049), thicker choroid (P < 0.001) but a lower portion of double-layer sign (P = 0.023) in OCT. Both groups showed significant anatomical changes compared to baseline in each follow-up period (P < 0.05), with the young group having a higher proportion of good anatomical response after the first injection (P = 0.009). CONCLUSION: PCV patients stratified by subtype exhibit distinct characteristics between the young and elderly groups.

Impacts of angiotensin II on retinal artery changes in apolipoprotein E deficient mice.

AIM: To investigate the impacts of angiotensin II (Ang II) on retinal artery changes in apolipoprotein E deficient (apoE-/-) mice. METHODS: apoE-/- male mice were infused by minipumps with Ang II at 1000 ng/kg·min (Ang II group) or saline (control group) for 28d. They were underwent ophthalmic fundus examination on day 0, 14, and 28 of infusion. Histopathologic examination, ribonucleic acid (RNA) sequencing and local Ang II measurement of retinas were conducted. RESULTS: Ophthalmic fundus examination showed Ang II infusion promoted the formation of retinal arterial aneurysm-like lesions on day 28. Optical coherence tomography revealed the ganglion cell and inner plexiform layer (GCIPL) thickness in the control group was significantly thinner than that in Ang II group (P<0.001). Hematoxylin-eosin staining demonstrated diffused swelling of GCIPL layer and its disordered structure in Ang II group. Transmission electron microscopy showed Ang II infusion caused aggravation of atherosclerotic lesions, including increased swelling, roughness, disorganization of the retinal vasculature, and vacuoles formation. RNA-sequencing and gene ontology enrichment analysis demonstrated that the structure and function of cellular membrane might be disturbed and visual function might be compromised by Ang II. The local level of Ang II was higher in Ang II infusion group but did not show significant differences compared to the control group (P=0.086). CONCLUSION: Ang II infusion promotes the formation of retinal arterial aneurysm-like lesions in apoE-/- mice, causing aggravation of atherosclerotic lesions, more severe disorganization of the retinal vasculature and disturbance of the cellular membrane.

A GH19 lysozyme and peptidase from Myoviridae cyanophages lacking the typical holin-endolysin system exhibit lytic activity.

Most of the dsDNA cyanophages employ holin-endolysin lysis systems to damage the host cells. This study aimed to elucidate the lytic activity of ORF91 and ORF117 in the cyanophage MaMV-DH01, which lacked a conventional cholinesterase system. These two proteins contained Lyz-like superfamily domains and were annotated as a member of GH family 19 (named DHGH19) and peptidase (named DHpeptidase), respectively. Overexpression of DHGH19 in E. coli over a 5 h course demonstrated potent bactericidal activity, evident from significant growth inhibition, membrane damage, and leakage of intracellular enzymes of E. coli cells. However, the lytic activity of DHpeptidase was relatively weaker, exhibiting a bacteriostatic effect. It was important to highlight that the specific mutation of enzyme-catalyzed residues in DHGH19 (E122 and E131) showed that these were the essential amino acids for DHGH19 to exert its bactericidal activity. Furthermore, the lytic function of DHGH19 and DHpeptidase on cyanobacteria cells was confirmed by their overexpression in the cyanobacterium Synechocystis sp. PCC6803. Overall, this study provides novel insights into the lytic mechanism of Myoviridae cyanophage, offering potential alternatives for the development of GH19 and peptidase as new antibacterial agents in the future.

Evaluation of the First-Dose Anti-VEGF Anatomical Response in Polypoidal Choroidal Vasculopathy Patients: Correlation with the Third-Dose Response and Risk Factor Analysis.

INTRODUCTION: The aims of the study were to investigate whether first-dose efficacy can predict third-dose anatomical response and analyze the risk factors for first-dose response of polypoidal choroidal vasculopathy (PCV) patients. METHODS: We retrospectively reviewed patients' medical records from 27 centers of China PCV Research Alliance. PCV patients treated with intravitreal injections of conbercept (IVC) based on the 3+ pro re nata regimen (three initial monthly injections, followed by injections as needed) with complete 3-month injection data were included. Response correlations, risk factor associations, changes in central macular thickness (CMT) or best-corrected visual acuity (BCVA), and number of injections in the first year of follow-up were evaluated separately in the pachy-PCV and non-pachy-PCV phenotypes. RESULTS: Overall, 165 eligible patients were included. There was a significant correlation between first-dose and third-dose anatomical response in pachy-PCV or non-pachy-PCV patients (rs = 0.611, p < 0.001; rs = 0.638, p < 0.001). Multivariate analysis revealed associations of good first-dose anatomical response in pachy-PCV patients with baseline CMT with a predicted area under the curve (AUC) of 0.847, while a good response in non-pachy-PCV patients was associated with baseline BCVA, baseline CMT, pigment epithelial detachment (PED) height, higher proportion of intraretinal fluid, and lower PED minimum diameter with a predicted AUC of 0.940. CMT in the good first-dose response group was significantly decreased from baseline at all first-year follow-up visits in both groups (p < 0.001), and mean BCVA was improved in the good versus poor first-dose anatomical response group (5.4 vs. 1.6 ETDRS letters in pachy-PCV, 10.6 vs. 7.4 letters in non-pachy-PCV) after the third injection. No significant difference was observed in the number of injections in the first year of follow-up between different response groups. CONCLUSION: In PCV patients receiving IVC, the first- and third-dose responses are significantly correlated, and different factors influence the first-dose response in different subtypes of PCV.

Scleral changes in systemic lupus erythematosus patients using swept source optical coherence tomography.

Purpose: This study aims to examine scleral thickness in patients with systemic lupus erythematosus (SLE) without clinically evident scleritis and episcleritis, utilizing swept-source optical coherence tomography (SS-OCT). Methods: This cross-sectional single center study compared scleral thickness (Nasal scleral thickness 1mm, 2mm, 3mm, 6mm from scleral spur; Temporal scleral thickness 1mm, 2mm, 3mm, 6mm from scleral spur) in 73 SLE patients without clinically evident scleritis and episcleritis and 48 healthy volunteers with SS-OCT. Further, we investigated the correlation between scleral thickness in SLE patients and various parameters including laboratory markers, disease duration, disease activity, and organ involvement. Results: Across all measured sites (nasal scleral thickness at distances of 1mm, 2mm, 3mm, and 6mm from the scleral spur, and temporal scleral thickness at the same distances), the scleral thickness in the SLE group was significantly greater than that in the control group (all p-values <0.001). SLE patients with a disease duration of 5 years or less exhibited a higher scleral thickness compared to those with a more prolonged disease duration. Patients with a higher erythrocyte sedimentation rate (ESR) had a thinner temporal scleral thickness. However, no significant associations were identified between scleral thickness and disease activity, organ involvement, or other laboratory markers. Conclusion: Scleral thickness measured by SS-OCT was higher in SLE patients than healthy controls. Changes in scleral thickness in SLE patients are related to disease duration and ESR. SS-OCT can detect asymptomatic structural changes in SLE patients and may be a useful tool in the evaluation of early scleral abnormality.

The incidence, risk factors, management and prognosis of postoperative systemic complications after ophthalmic surgery: a retrospective study at a tertiary, academic referral hospital over a decade.

PURPOSE: To explore the incidence, risk factors, management and prognosis of systemic complications after ophthalmic surgeries. METHODS: A retrospective review of hospitalized patients undergoing ophthalmic surgeries between 2012 and 2022 at Peking Union Medical College Hospital was performed to summarize and analyse the postoperative systemic complications. Multivariate logistic and linear regression analyses were conducted to clarify the risk factors of postoperative systemic complications and factors associated with the severity of adverse events. RESULTS: A total of 34,841 patients underwent inpatient ophthalmic surgery, among which 162 systemic complications occurred in 150 patients during postoperative hospitalization. The overall incidence rate was 0.4%, with cardiovascular events (48.1%), digestive events (13.6%) and fever (12.3%) being the leading causes. About 17.3% of the cases had conditions improved after observation, 19.1% after symptomatic treatment, 54.9% had consultation with specific intervention and 8.6% were transferred to the corresponding departments for specialized treatment. For the prognosis, 93.8% had condition improved, 5.6% chose voluntary discharge without improvement, and one patient died of respiratory failure caused by postoperative pulmonary infection. The worse ADL (activities of daily living) grading, indication of primary intraocular lymphoma or intraocular tumour, surgery of simple pars plana vitrectomy (PPV), PPV with silicone oil tamponade, PPV with gas tamponade, general anaesthesia, history of diabetes mellitus (DM), chronic heart failure and digestive system disease were the risk factors positively correlated with postoperative systemic complications (p < .05). The worse ADL grading, history of DM and respiratory system disease were also positively correlated with the severity of the adverse events (p < .05). CONCLUSIONS: The incidence of postoperative systemic complications was low among patients undergoing ophthalmic surgery, most were mild and could be relieved after observation, symptomatic or specialist consultation. Patients with worse ADL and history of DM should be paid extra attention.

Heparan sulfate is the attachment factor associated with channel catfish virus infection on host cells.

Channel catfish virus (CCV; family Alloherpesviridae) infects channel catfish, causing great harm to aquaculture fisheries and economic development. Attachment is the first step in viral infection and relies on the interaction of virions with components of the extracellular matrix (ECM). The present study aimed to explored the role of the main three ECM components in CCV attachment. Western blotting and quantitative real-time PCR analysis showed that neither collagen nor hyaluronic acid treatments had significant effects on CCV attachment. When exogenous heparin was used as a competitive inhibitor, the adhesion of heparin sodium salt to CCV was dose-dependent. When the concentration of heparin sodium salt was 10 mg/mL, the inhibitory effect on CCV infection of channel catfish ovary (CCO/BB) cells was more than 90%. Heparinase I could significantly prevent CCV attachment by digesting heparan sulfate on the cell surface, and both heparin sodium salt and heparinase I could dose-dependently reduce CCV titers, suggesting that heparin plays an important role in CCV attachment. In addition, the binding experiments between heparin-agarose beads and virions showed that CCV virions could specifically bind to heparin in a dose-dependent manner. The above results suggested that heparan sulfate might be an attachment factor involved in CCV infection of CCO/BB cells. These results increase our understand of the attachment mechanism of CCV and lay the foundation for further research on antiviral drugs.