Long-term mortality in patients with end-stage renal disease undergoing hemodialysis and peritoneal dialysis: a propensity score matching retrospective study

BACKGROUND

Hemodialysis (HD) and peritoneal dialysis (PD) are effective ways to treat end-stage renal disease (ERSD). This study aimed to investigate the differences in survival and the factors that influence it in patients with end-stage renal disease treated with HD or PD.

METHODS

We retrospectively analyzed factors related to all-cause death with renal replacement therapy and compared the long-term mortality between HD and PD strategies in patients with ESRD who started HD or PD treatment in our renal HD center between January 1, 2008, and December 1, 2021.

RESULTS

Overall, 1,319 patients were included, comprising 690 and 629 patients in the HD and PD groups, respectively, according to the inclusion criteria. After propensity matching, 922 patients remained, with 461 (50%) patients each in the two groups. There were no significant differences in the 1-, 2-, 3-, and 4-year mortality rates between the HD and PD groups (all p > .05). However, the 5- and 10-year mortality rates of the matched patients were 15.8%. 17.6% in the HD group and 21.0%. 27.3% in the PD group, respectively. The 5- and 10-year mortality rates were significantly lower in the HD group (all p < .05) as compared to the PD group. After matching, Kaplan-Meier curve analysis with log-rank test was performed, which showed a significant difference in the survival rates between the two groups (p = .001). Logistic multifactor regression analysis revealed that age, weight, hypertension, serum creatinine, and combined neoplasms influenced the survival rate of patients with ESRD (p < .05). In contrast, age, hypertension, parathyroid hormone (PTH), serum creatinine, and peripheral vascular diseases (PVD) influenced the survival rate of patients in the HD group (p < .05), and age and weight influenced the survival rate of patients in the PD group (p < .05).

CONCLUSIONS

This study found that long-term mortality rates were higher in the PD group than that in the HD group, indicating that HD may be superior to PD.

Large enhancement of red upconversion luminescence in beta Ba2Sc0.67Yb0.3Er0.03AlO5 phosphor via Mn2+ ions doping for thermometry

Here, this study reports single-band red upconversion emission in β-Ba2ScAlO5: Yb3+/Er3+ phosphor by doping Mn2+. The optimum concentration of Mn2+ ions in β-Ba2ScAlO5: Yb3+/Er3+ phosphor was 0.20. The intensity of red and green emissions is increased by 27.4 and 19.3 times, respectively. Compared with the samples without Mn2+ ions, the red-green integral strength ratio of β-Ba2ScAlO5: Yb3+/Er3+/Mn2+ sample was significantly increased by 28.4 times, reaching 110.9. The UCL mechanism was explored by analyzing the down-conversion luminescence spectra, absorption spectra, UCL spectra, and upconversion fluorescence lifetime decay curves of Yb3+/Er3+/Mn2+ co-doped β-Ba2ScAlO5. The enhancement of upconversion red light is achieved through energy transfer between defect bands and Er3+ ions, as well as energy transfer between Mn2+ ions and Er3+ ions. In addition, the Mn2+ doped β-Ba2ScAlO5: Yb3+/Er3+ red UCL phosphors have great potential for ambient temperature sensing in the 298-523 K temperature range. The maximum sensitivity of β-Ba2ScAlO5: Yb3+/Er3+/Mn2+ phosphor as a temperature sensor at 523 K is 0.0247 K-1.

Differentiated mesenchymal stem cells-derived exosomes immobilized in decellularized sciatic nerve hydrogels for peripheral nerve repair

Peripheral nerve injury (PNI) and the limitations of current treatments often result in incomplete sensory and motor function recovery, which significantly impact the patient's quality of life. While exosomes (Exo) derived from stem cells and Schwann cells have shown promise on promoting PNI repair following systemic administration or intraneural injection, achieving effective local and sustained Exo delivery holds promise to treat local PNI and remains challenging. In this study, we developed Exo-loaded decellularized porcine nerve hydrogels (DNH) for PNI repair. We successfully isolated Exo from differentiated human adipose-derived mesenchymal stem cells (hADMSC) with a Schwann cell-like phenotype (denoted as dExo). These dExo were further combined with polyethylenimine (PEI), and DNH to create polyplex hydrogels (dExo-loaded pDNH). At a PEI content of 0.1%, pDNH showed cytocompatibility for hADMSCs and supported neurite outgrowth of dorsal root ganglions. The sustained release of dExos from dExo-loaded pDNH persisted for at least 21 days both in vitro and in vivo. When applied around injured nerves in a mouse sciatic nerve crush injury model, the dExo-loaded pDNH group significantly improved sensory and motor function recovery and enhanced remyelination compared to dExo and pDNH only groups, highlighting the synergistic regenerative effects. Interestingly, we observed a negative correlation between the number of colony-stimulating factor-1 receptor (CSF-1R) positive cells and the extent of PNI regeneration at the 21-day post-surgery stage. Subsequent in vitro experiments demonstrated the potential involvement of the CSF-1/CSF-1R axis in Schwann cells and macrophage interaction, with dExo effectively downregulating CSF-1/CSF-1R signaling.

Multi-slice spatial transcriptome domain analysis with SpaDo

With the rapid advancements in spatial transcriptome sequencing, multiple tissue slices are now available, enabling the integration and interpretation of spatial cellular landscapes. Herein, we introduce SpaDo, a tool for multi-slice spatial domain analysis, including modules for multi-slice spatial domain detection, reference-based annotation, and multiple slice clustering at both single-cell and spot resolutions. We demonstrate SpaDo's effectiveness with over 40 multi-slice spatial transcriptome datasets from 7 sequencing platforms. Our findings highlight SpaDo's potential to reveal novel biological insights in multi-slice spatial transcriptomes.

Digital Light Processing 4D Printing of Poloxamer Micelles for Facile Fabrication of Multifunctional Biocompatible Hydrogels as Tailored Wearable Sensors

The lack of both digital light processing (DLP) compatible and biocompatible photopolymers, along with inappropriate material properties required for wearable sensor applications, substantially hinders the employment of DLP 3D printing in the fabrication of multifunctional hydrogels. Herein, we discovered and implemented a photoreactive poloxamer derivative, Pluronic F-127 diacrylate, which overcomes these limitations and is optimized to achieve DLP 3D printed micelle-based hydrogels with high structural complexity, resolution, and precision. In addition, the dehydrated hydrogels exhibit a shape-memory effect and are conformally attached to the geometry of the detection point after rehydration, which implies the 4D printing characteristic of the fabrication process and is beneficial for the storage and application of the device. The excellent cytocompatibility and in vivo biocompatibility further strengthen the potential application of the poloxamer micelle-based hydrogels as a platform for multifunctional wearable systems. After processing them with a lithium chloride (LiCl) solution, multifunctional conductive ionic hydrogels with antifreezing and antiswelling properties along with good transparency and water retention are easily prepared. As capacitive flexible sensors, the DLP 3D printed micelle-based hydrogel devices exhibit excellent sensitivity, cycling stability, and durability in detecting multimodal deformations. Moreover, the DLP 3D printed conductive hydrogels are successfully applied as real-time human motion and tactile sensors with satisfactory sensing performances even in a -20 °C low-temperature environment.

Octanal enhances disease resistance in postharvest citrus fruit by the biosynthesis and metabolism of aromatic amino acids

Octanal was found to be able to reduce green mold incidence in citrus fruit by a defense response mechanism. However, the underlying mechanism remains largely unclear. Herein, the metabolomics, RNA-seq and biochemical analyses were integrated to explore the effect of octanal on disease resistance in harvested citrus fruit. Results showed that octanal fumigation at 40 μL L-1 was effective in controlling citrus green mold. Metabolomics analysis showed that octanal mainly led to the accumulation of some plant hormones including methyl jasmonate, abscisic acid, indole-3-butyric acid, indoleacetic acid (IAA), salicylic acid, and gibberellic acid and many phenylpropanoid metabolites including cinnamyl alcohol, hesperidin, dihydrokaempferol, vanillin, quercetin-3-O-malonylglucoside, curcumin, naringin, chrysin, coniferin, calycosin-7-O-β-D-glucoside, trans-cinnamaldehyde, and 4',5,7-trihydroxy-3,6-dimethoxyflavone. Particularly, IAA and hesperidin were dramatically accumulated in the peel, which might be the contributors to the resistance response. Additionally, transcriptome analysis showed that octanal greatly activated the biosynthesis and metabolism of aromatic amino acids. This was further verified by the accumulation of some metabolites (shikimic acid, tryptophan, tyrosine, phenylalanine, IAA, total phenolics, flavonoids and lignin), increase in some enzyme activities (phenylalanine ammonia-lyase, tyrosine ammonia-lyase, 4-coumarate CoA ligase, cinnamic acid 4-hydroxylase, polyphenol oxidase, and peroxidase), up-regulation of some genes (tryptophan pyruvate aminotransferase, aldehyde dehydrogenase, shikimate kinase and shikimate dehydrogenase) expressions and molecular docking results. Thus, these results indicate that octanal is an efficient strategy for the control of postharvest green mold by triggering the defense response in citrus fruit.

Multiscale embedded printing of engineered human tissue and organ equivalents

Creating tissue and organ equivalents with intricate architectures and multiscale functional feature sizes is the first step toward the reconstruction of transplantable human tissues and organs. Existing embedded ink writing approaches are limited by achievable feature sizes ranging from hundreds of microns to tens of millimeters, which hinders their ability to accurately duplicate structures found in various human tissues and organs. In this study, a multiscale embedded printing (MSEP) strategy is developed, in which a stimuli-responsive yield-stress fluid is applied to facilitate the printing process. A dynamic layer height control method is developed to print the cornea with a smooth surface on the order of microns, which can effectively overcome the layered morphology in conventional extrusion-based three-dimensional bioprinting methods. Since the support bath is sensitive to temperature change, it can be easily removed after printing by tuning the ambient temperature, which facilitates the fabrication of human eyeballs with optic nerves and aortic heart valves with overhanging leaflets on the order of a few millimeters. The thermosensitivity of the support bath also enables the reconstruction of the full-scale human heart on the order of tens of centimeters by on-demand adding support bath materials during printing. The proposed MSEP demonstrates broader printable functional feature sizes ranging from microns to centimeters, providing a viable and reliable technical solution for tissue and organ printing in the future.

Characterization of Antimicrobial Poly(Lactic Acid)- and Polyurethane-Based Materials Enduring Closed-Loop Recycling with Applications in Space

Recent studies have shown that astronauts experience altered immune response behavior during spaceflight, resulting in heightened susceptibility to illness. Resources and resupply shuttles will become scarcer with longer duration spaceflight, limiting access to potentially necessary medical treatment and facilities. Thus, there is a need for preventative health countermeasures that can exploit in situ resource utilization technologies during spaceflight, such as additive manufacturing (i.e., 3D printing). The purpose of the current study was to test and validate recyclable antimicrobial materials compatible with additive manufacturing. Antimicrobial poly(lactic acid)- and polyurethane-based materials compatible with 3D printing were assessed for antimicrobial, mechanical, and chemical characteristics before and after one closed-loop recycling cycle. Our results show high biocidal efficacy (>90%) of both poly(lactic acid) and polyurethane materials while retaining efficacy post recycling, except for recycled-state polyurethane which dropped from 98.91% to 0% efficacy post 1-year accelerated aging. Significant differences in tensile and compression characteristics were observed post recycling, although no significant changes to functional chemical groups were found. Proof-of-concept medical devices developed show the potential for the on-demand manufacturing and recyclability of typically single-use medical devices using antimicrobial materials that could serve as preventative health countermeasures for immunocompromised populations, such as astronauts during spaceflight.

Evaluation of Tyrosine Kinase Inhibitors Loaded Injectable Hydrogels for Improving Connexin43 Gap Junction Intercellular Communication

Myocardial infarction (MI) is one of the leading causes of death in the developed world, and the loss of cardiomyocytes plays a critical role in the pathogenesis of heart failure. Implicated in this process is a decrease in gap junction intercellular communication due to remodeling of Connexin43 (Cx43). We previously identified that intraperitoneal injection of the Pyk2 inhibitor PF4618433 reduced infarct size, maintained Cx43 at the intercalated disc in left ventricle hypertrophic myocytes, and improved cardiac function in an MI animal model of heart failure. With the emergence of injectable hydrogels as a therapeutic toward the regeneration of cardiac tissue after MI, here, we provide proof of concept that the release of tyrosine kinase inhibitors from hydrogels could have beneficial effects on cardiomyocytes. We developed an injectable hydrogel consisting of thiolated hyaluronic acid and P123-maleimide micelles that can incorporate PF4618433 as well as the Src inhibitor Saracatinib and achieved sustained release (of note, Src activates Pyk2). Using neonatal rat ventricular myocytes in the presence of a phorbol ester, endothelin-1, or phenylephrine to stimulate cardiac hypertrophy, the release of PF4618433 from the hydrogel had the same ability to decrease Cx43 tyrosine phosphorylation and maintain Cx43 localization at the plasma membrane as when directly added to the growth media. Additional beneficial effects included decreases in apoptosis, the hypertrophic marker atrial natriuretic peptide (ANP), and serine kinases upregulated in hypertrophy. Finally, the presence of both PF4618433 and Saracatinib further decreased the level of ANP and apoptosis than each inhibitor alone, suggesting that a combinatorial approach may be most beneficial. These findings provide the groundwork to test if tyrosine kinase inhibitor release from hydrogels will have a beneficial effect in an animal model of MI-induced heart failure.

Engineering Neurotoxin-Functionalized Exosomes for Targeted Delivery to the Peripheral Nervous System

The administration of therapeutics to peripheral nerve tissue is challenging due to the complexities of peripheral neuroanatomy and the limitations imposed by the blood-nerve barrier (BNB). Therefore, there is a pressing need to enhance delivery effectiveness and implement targeted delivery methods. Recently, erythrocyte-derived exosomes (Exos) have gained widespread attention as biocompatible vehicles for therapeutics in clinical applications. However, engineering targeted Exos for the peripheral nervous system (PNS) is still challenging. This study aims to develop a targeted Exo delivery system specifically designed for presynaptic terminals of peripheral nerve tissue. The clostridium neurotoxin, tetanus toxin-C fragment (TTC), was tethered to the surface of red blood cell (RBC)-derived Exos via a facile and efficient bio-orthogonal click chemistry method without a catalyst. Additionally, Cyanine5 (Cy5), a reactive fluorescent tag, was also conjugated to track Exo movement in both in vitro and in vivo models. Subsequently, Neuro-2a, a mouse neuronal cell line, was treated with dye-labeled Exos with/without TTC in vitro, and the results indicated that TTC-Exos exhibited more efficient accumulation along the soma and axonal circumference, compared to their unmodified counterparts. Further investigation, using a mouse model, revealed that within 72 h of intramuscular administration, engineered TTC-Exos were successfully transported into the neuromuscular junction and sciatic nerve tissues. These results indicated that TTC played a crucial role in the Exo delivery system, improving the affinity to peripheral nerves. These promising results underscore the potential of using targeted Exo carriers to deliver therapeutics for treating peripheral neuropathies.

YAP mechanotransduction under cyclic mechanical stretch loading for mesenchymal stem cell osteogenesis is regulated by ROCK

While yes-associated protein (YAP) is now recognized as a potent mechanosensitive transcriptional regulator to affect cell growth and differentiation including the osteogenic transcription of mesenchymal stem cells (MSCs), most studies have reported the YAP mechanosensing of static mechanophysical cues such as substrate stiffness. We tested MSC response to dynamic loading, i.e., cyclic mechanical stretching, and assessed YAP mechanosensing and resultant MSC osteogenesis. We showed that cyclic stretching at 10% strain and 1 Hz frequency triggered YAP nuclear import in MSCs. YAP phosphorylation at S127 and S397, which is required for YAP cytoplasmic retention, was suppressed by cyclic stretch. We also observed that anti-YAP-regulatory Hippo pathway, LATS phosphorylation, was significantly decreased by stretch. We confirmed the stretch induction of MSC osteogenic transcription and differentiation, and this was impaired under YAP siRNA suggesting a key role of YAP dynamic mechanosensing in MSC osteogenesis. As an underlying mechanism, we showed that the YAP nuclear transport by cyclic stretch was abrogated by ROCK inhibitor, Y27632. ROCK inhibitor also impaired the stretch induction of F-actin formation and MSC osteogenesis, thus implicating the role of the ROCK-F-actin cascade in stretch-YAP dynamic mechanosensing-MSC osteogenesis. Our results provide insight into bone tissue engineering and skeletal regenerative capacity of MSCs especially as regards the role of dynamic mechanical loading control of YAP-mediated MSC osteogenic transcription.

Structure-decoupled functional connectome-based brain age prediction provides higher association to cognition

Brain age prediction as well as the prediction difference has been well examined to be a potential biomarker for brain disease or abnormal aging process. However, less knowledge was reported for the cognitive association within normal population. In this study, we proposed a novel approach to brain age prediction by structure-decoupled functional connectome. The original functional connectome was decomposed and decoupled into a structure-decoupled functional connectome using structural connectome harmonics. Our method was applied to a large dataset of normal aging individuals and achieved a high correlation between predicted and chronological age (r = 0.77). Both the original FC and structure-decoupled FC could be well-trained in a brain age prediction model. Significant remarkable relationships between the brain age prediction difference (predicted age minus chronological age) and cognitive scores were discovered. However, the brain age-predicted difference driven by structure-decoupled FC showed a stronger correction to the two cognitive scores (MMSE: r = -0.27, P -value = 0.002; MoCA: r = -0.32, P -value = 0.0003). Our findings suggest that our structure-decoupled functional connectivity approach could provide a more individual-specific functional network, leading to improved brain age prediction performance and a better understanding of cognitive decline in aging.

Personalized tumor combination therapy optimization using the single-cell transcriptome

BACKGROUND

The precise characterization of individual tumors and immune microenvironments using transcriptome sequencing has provided a great opportunity for successful personalized cancer treatment. However, the cancer treatment response is often characterized by in vitro assays or bulk transcriptomes that neglect the heterogeneity of malignant tumors in vivo and the immune microenvironment, motivating the need to use single-cell transcriptomes for personalized cancer treatment.

METHODS

Here, we present comboSC, a computational proof-of-concept study to explore the feasibility of personalized cancer combination therapy optimization using single-cell transcriptomes. ComboSC provides a workable solution to stratify individual patient samples based on quantitative evaluation of their personalized immune microenvironment with single-cell RNA sequencing and maximize the translational potential of in vitro cellular response to unify the identification of synergistic drug/small molecule combinations or small molecules that can be paired with immune checkpoint inhibitors to boost immunotherapy from a large collection of small molecules and drugs, and finally prioritize them for personalized clinical use based on bipartition graph optimization.

RESULTS

We apply comboSC to publicly available 119 single-cell transcriptome data from a comprehensive set of 119 tumor samples from 15 cancer types and validate the predicted drug combination with literature evidence, mining clinical trial data, perturbation of patient-derived cell line data, and finally in-vivo samples.

CONCLUSIONS

Overall, comboSC provides a feasible and one-stop computational prototype and a proof-of-concept study to predict potential drug combinations for further experimental validation and clinical usage using the single-cell transcriptome, which will facilitate and accelerate personalized tumor treatment by reducing screening time from a large drug combination space and saving valuable treatment time for individual patients. A user-friendly web server of comboSC for both clinical and research users is available at www.combosc.top . The source code is also available on GitHub at https://github.com/bm2-lab/comboSC .

Diagnosis of spinal dural arteriovenous fistula: a multimodal MRI assessment strategy

AIM

To identify more specific screening indicators at magnetic resonance imaging (MRI) for the diagnosis of spinal dural arteriovenous fistulas (SDAVFs) and to determine an efficient diagnostic strategy.

MATERIALS AND METHODS

This retrospective study analysed clinical and imaging data of patients diagnosed with SDAVF and alternative myelopathy who underwent conventional MRI examinations. Additionally, three-dimensional (3D) T2-weighted sampling perfection with application-optimised contrasts using different flip-angle evolutions (3D-T2-SPACE) and contrast-enhanced magnetic resonance angiography (CE-MRA) data from patients with SDAVF were compared with digital subtraction angiography (DSA) data.

RESULTS

The age of onset, perimedullary flow voids (PFV), distribution of lesions, syringomyelia, degree of spinal oedema, and cauda equina disorder (CED) were factors that showed statistically significance in the identification of SDAVF with alternative myelopathy. After controlling for age, gender, PFV, degree of spinal cord swelling, and syringomyelia, the multivariable ordinal logistic regression model showed that the CED sign (OR = 32.46; 95% confidence interval [CI]: 2.47-427.15; p=0.008) was an independent predictor for SDAVF. The diagnostic model constructed using the PFV and CED signs had better diagnostic performance, with an area under the curve of 0.957 (p<0.001), maximum Youden index of 0.844, sensitivity of 92.9%, and specificity of 91.5%. Both 3D-T2-SPACE (77.8%) and CE-MRA (83.3%) sequences had good localisation values for SDAVF. Combining the two imaging examinations had better diagnostic accuracy than that of DSA.

CONCLUSION

CED and PFV on conventional MRI were specific indicators for the diagnosis of SDAVF. To compensate for the lack of fistula localisation on conventional MRI, 3D-T2-SPACE and CE-MRA can be used. Together they complement each other and have good diagnostic potential.

Tumor Treatment Response Assessed During the Concurrent Chemoradiotherapy for Nasopharyngeal Patients

PURPOSE/OBJECTIVE(S)

To evaluate intratumoral treatment response distribution with using FDG-PET/CT during the chemoradiotherapy of nasopharyngeal patients (NPC).

MATERIALS/METHODS

A total of 5 of 30 patients with stage III-IVA NPC were enrolled in the institutional protocol for induction/concurrent chemoradiotherapy with radiation dose of 70 Gy in 33 fractions. For each patient, a pre-radiation treatment FDG-PET/MRI image (SUV0) and a mid-treatment image (SUVm) at the treatment dose of 31.8 Gy were obtained. Followed by deformable PET/MRI registration between SUV0 and SUVm, the tumor voxel SUV reduction ratio was obtained to construct a tumor dose response matrix (DRM). Tumor SUVavid was also constructed by limiting tumor voxel SUVm > a given value. Spatial correlations of the tumor SUV0, SUVm, SUVavid and DRM were determined.

RESULTS

The mean and coefficient variation (CV) of the SUV0, SUVm and DRM for all tumors were 5.05 (52%), 2.72 (49%) and 0.64 (63%) (Table contains the individual data), which were smaller than those on the SUVs of head-n-neck HPV+ patients reported previously due to the induction chemotherapy, but had much larger DRM mean and CV. The inter-tumoral CVs of SUV0 and DRM were 29% and 27%, which were much lower than those of the intra-tumoral CVs 43% and 57%. Meanwhile, the intra-tumoral variations on SUV0 was smaller than the one of head-neck HPV+ patients, but the DRM intra-variation was much larger. There was a weak correlation between SUV0 and SUVm with the correlation coefficient 0.13, a medium correlation of -0.55 between SUV0 and DRM, but a strong correlation, 0.72, between SUVm and DRM. However, the spatial correlation between tumor DRM and SUVavid was getting weaker as the SUVavid value increasing and equal 0.47 with SUVavid value > 3.

CONCLUSION

The spatial dose response DRM for NPC in the concurrent chemoradiotherapy was relatively high, while had relatively low baseline tumor metabolic activity SUV0. It was most likely due to the induction chemotherapy. In addition, the tumor dose response showed vary large intra-tumoral variation. The high correlations between DRM and SUVm imply that SUVavid could be used partially to guide adaptive modification of NPC treatment with carefully selected boundary value.

Embedded Bioprinting of Breast Tumor Cells and Organoids Using Low-Concentration Collagen-Based Bioinks

Bioinks for 3D bioprinting of tumor models should not only meet printability requirements but also accurately maintain and support phenotypes of tumor surrounding cells to recapitulate key tumor hallmarks. Collagen is a major extracellular matrix protein for solid tumors, but low viscosity of collagen solution has made 3D bioprinted cancer models challenging. This work produces embedded, bioprinted breast cancer cells and tumor organoid models using low-concentration collagen I based bioinks. The biocompatible and physically crosslinked silk fibroin hydrogel is used to generate the support bath for the embedded 3D printing. The composition of the collagen I based bioink is optimized with a thermoresponsive hyaluronic acid-based polymer to maintain the phenotypes of both the noninvasive epithelial and invasive breast cancer cells, as well as cancer-associated fibroblasts. Mouse breast tumor organoids are bioprinted using optimized collagen bioink to mimic in vivo tumor morphology. A vascularized tumor model is also created using a similar strategy, with significantly enhanced vasculature formation under hypoxia. This study shows the great potential of embedded bioprinted breast tumor models utilizing a low-concentration collagen-based bioink for advancing the understanding of tumor cell biology and facilitating drug discovery research.

Advances, challenges, and prospects for surgical suture materials

As one of the long-established and necessary medical devices, surgical sutures play an essentially important role in the closing and healing of damaged tissues and organs postoperatively. The recent advances in multiple disciplines, like materials science, engineering technology, and biomedicine, have facilitated the generation of various innovative surgical sutures with humanization and multi-functionalization. For instance, the application of numerous absorbable materials is assuredly a marvelous progression in terms of surgical sutures. Moreover, some fantastic results from recent laboratory research cannot be ignored either, ranging from the fiber generation to the suture structure, as well as the suture modification, functionalization, and even intellectualization. In this review, the suture materials, including natural or synthetic polymers, absorbable or non-absorbable polymers, and metal materials, were first introduced, and then their advantages and disadvantages were summarized. Then we introduced and discussed various fiber fabrication strategies for the production of surgical sutures. Noticeably, advanced nanofiber generation strategies were highlighted. This review further summarized a wide and diverse variety of suture structures and further discussed their different features. After that, we covered the advanced design and development of surgical sutures with multiple functionalizations, which mainly included surface coating technologies and direct drug-loading technologies. Meanwhile, the review highlighted some smart and intelligent sutures that can monitor the wound status in a real-time manner and provide on-demand therapies accordingly. Furthermore, some representative commercial sutures were also introduced and summarized. At the end of this review, we discussed the challenges and future prospects in the field of surgical sutures in depth. This review aims to provide a meaningful reference and guidance for the future design and fabrication of innovative surgical sutures. STATEMENT OF SIGNIFICANCE: This review article introduces the recent advances of surgical sutures, including material selection, fiber morphology, suture structure and construction, as well as suture modification, functionalization, and even intellectualization. Importantly, some innovative strategies for the construction of multifunctional sutures with predetermined biological properties are highlighted. Moreover, some important commercial suture products are systematically summarized and compared. This review also discusses the challenges and future prospects of advanced sutures in a deep manner. In all, this review is expected to arouse great interest from a broad group of readers in the fields of multifunctional biomaterials and regenerative medicine.

A Facile Strategy for the Fabrication of Cell-laden Porous Alginate Hydrogels Based on Two-phase Aqueous Emulsions

Porous alginate hydrogels possess many advantages as cell carriers. However, current pore generation methods require either complex or harsh fabrication processes, toxic components, or extra purification steps, limiting the feasibility and affecting the cellular survival and function. In this study, a simple and cell-friendly approach to generate highly porous cell-laden alginate hydrogels based on two-phase aqueous emulsions is reported. The pre-gel solutions, which contain two immiscible aqueous phases of alginate and caseinate, are crosslinked by calcium ions. The porous structure of the hydrogel construct is formed by subsequently removing the caseinate phase from the ion-crosslinked alginate hydrogel. Those porous alginate hydrogels possess heterogeneous pores around 100 μm and interconnected paths. Human white adipose progenitors (WAPs) encapsulated in these hydrogels self-organize into spheroids and show enhanced viability, proliferation, and adipogenic differentiation, compared to non-porous constructs. As a proof of concept, this porous alginate hydrogel platform is employed to prepare core-shell spheres for coculture of WAPs and colon cancer cells, with WAP clusters distributed around cancer cell aggregates, to investigate cellular crosstalk. This efficacious approach is believed to provide a robust and versatile platform for engineering porous-structured alginate hydrogels for applications as cell carriers and in disease modeling.

Epigenetic Regulation of Leukocyte Inflammatory Mediator Production Dictates Staphylococcus aureus Craniotomy Infection Outcome

Staphylococcus aureus is a common cause of surgical-site infections, including those arising after craniotomy, which is performed to access the brain for the treatment of tumors, epilepsy, or hemorrhage. Craniotomy infection is characterized by complex spatial and temporal dynamics of leukocyte recruitment and microglial activation. We recently identified unique transcriptional profiles of these immune populations during S. aureus craniotomy infection. Epigenetic processes allow rapid and reversible control over gene transcription; however, little is known about how epigenetic pathways influence immunity to live S. aureus. An epigenetic compound library screen identified bromodomain and extraterminal domain-containing (BET) proteins and histone deacetylases (HDACs) as critical for regulating TNF, IL-6, IL-10, and CCL2 production by primary mouse microglia, macrophages, neutrophils, and granulocytic myeloid-derived suppressor cells in response to live S. aureus. Class I HDACs (c1HDACs) were increased in these cell types in vitro and in vivo during acute disease in a mouse model of S. aureus craniotomy infection. However, substantial reductions in c1HDACs were observed during chronic infection, highlighting temporal regulation and the importance of the tissue microenvironment for dictating c1HDAC expression. Microparticle delivery of HDAC and BET inhibitors in vivo caused widespread decreases in inflammatory mediator production, which significantly increased bacterial burden in the brain, galea, and bone flap. These findings identify histone acetylation as an important mechanism for regulating cytokine and chemokine production across diverse immune cell lineages that is critical for bacterial containment. Accordingly, aberrant epigenetic regulation may be important for promoting S. aureus persistence during craniotomy infection.

γ-Cyclodextrin encapsulated thymol for citrus preservation and its possible mechanism against Penicillium digitatum

The volatility of essential oils greatly limits their industrial applications. Here, we successfully prepared γ-cyclodextrin (γ-CD) inclusion compounds (γ-CDTL) containing thymol (TL) for the control of green mold caused by Penicillium digitatum (P. digitatum) in citrus fruit. In vitro experiment showed that the minimum fungicidal concentration (MFC) of γ-CDTL against the hyphae growth of P. digitatum was 2.0 g/L, and 8 × MFC treatment significantly reduced the occurrence of green mold in citrus fruit and had no adverse effect on fruit quality in vivo test compared to prochloraz. Scanning electron microscopy (SEM), x-ray diffraction (XRD), fourier transform-infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), physical properties and sustained release properties were also performed, results indicated that the hydrogen bonds between TL and γ-CD were the basis for the formation of γ-CDTL. We further investigated the inhibition mechanism of γ-CDTL. SEM and TEM experiments showed that γ-CDTL treatment caused severe damage to the hyphal morphology and cells in 30 min and disrupted the permeability of P. digitatum mycelial cell walls by increasing the chitinase activity, thus accelerating the leakage of intracellular lysates. However, the integrity of the cell membrane was obviously damaged only after 60 min of treatment. In conclusion, we prepared a novel inclusion complex γ-CDTL with obvious antifungal effects and preliminarily elucidated its inclusion mechanism and antifungal mechanism. γ-CDTL might be a potent alternative to chemical fungicides for controlling the postharvest decay of citrus.

IL-10 production by granulocytes promotes Staphylococcus aureus craniotomy infection

BACKGROUND

Treatment of brain tumors, epilepsy, or hemodynamic abnormalities requires a craniotomy to access the brain. Nearly 1 million craniotomies are performed in the US annually, which increase to ~ 14 million worldwide and despite prophylaxis, infectious complications after craniotomy range from 1 to 3%. Approximately half are caused by Staphylococcus aureus (S. aureus), which forms a biofilm on the bone flap that is recalcitrant to antibiotics and immune-mediated clearance. However, the mechanisms responsible for the persistence of craniotomy infection remain largely unknown. The current study examined the role of IL-10 in promoting bacterial survival.

METHODS

A mouse model of S. aureus craniotomy infection was used with wild type (WT), IL-10 knockout (KO), and IL-10 conditional KO mice where IL-10 was absent in microglia and monocytes/macrophages (CX3CR1CreIL-10 fl/fl) or neutrophils and granulocytic myeloid-derived suppressor cells (G-MDSCs; Mrp8CreIL-10 fl/fl), the major immune cell populations in the infected brain vs. subcutaneous galea, respectively. Mice were examined at various intervals post-infection to quantify bacterial burden, leukocyte recruitment, and inflammatory mediator production in the brain and galea to assess the role of IL-10 in craniotomy persistence. In addition, the role of G-MDSC-derived IL-10 on neutrophil activity was examined.

RESULTS

Granulocytes (neutrophils and G-MDSCs) were the major producers of IL-10 during craniotomy infection. Bacterial burden was significantly reduced in IL-10 KO mice in the brain and galea at day 14 post-infection compared to WT animals, concomitant with increased CD4+ and γδ T cell recruitment and cytokine/chemokine production, indicative of a heightened proinflammatory response. S. aureus burden was reduced in Mrp8CreIL-10 fl/fl but not CX3CR1CreIL-10 fl/fl mice that was reversed following treatment with exogenous IL-10, suggesting that granulocyte-derived IL-10 was important for promoting S. aureus craniotomy infection. This was likely due, in part, to IL-10 production by G-MDSCs that inhibited neutrophil bactericidal activity and TNF production.

CONCLUSION

Collectively, these findings reveal a novel role for granulocyte-derived IL-10 in suppressing S. aureus clearance during craniotomy infection, which is one mechanism to account for biofilm persistence.

Red blood cell membrane-camouflaged poly(lactic-co-glycolic acid) microparticles as a potential controlled release drug delivery system for local stellate ganglion microinjection

The stellate ganglion (SG) is a part of the sympathetic nervous system that has important regulatory effects on several human tissues and organs in the upper body. SG block and intervention have been clinically and preclinically implemented to manage chronic pain in the upper extremities, neck, head, and upper chest as well as chronic heart failure. However, there has been very limited effort to develop and investigate polymer-based drug delivery systems for local delivery to the SG. In this study, we fabricated red blood cell (RBC) membrane-camouflaged poly(lactic-co-glycolic acid) (PLGA) (PLGAM) microparticles for use as a potential long-term controlled release system for local drug delivery. The structure, size, and surface zeta potential results indicated that the spherical PLGAM microparticles were successfully fabricated. Both PLGA and PLGAM microparticles exhibited biocompatibility with human adipose mesenchymal stem cells (ADMSC) and satellite glial cells and showed hemocompatibility. In addition, both PLGA and PLGAM displayed no significant effects on the secretion of proinflammatory cytokines by human monocyte derived macrophages in vitro. We microinjected microparticles into rat SGs and evaluated the retention time of microparticles and the effects of the microparticles on inflammation in vivo over 21 days. Subsequently, we fabricated drug-loaded PLGAM microparticles by using GW2580, a colony stimulating factor-1 receptor inhibitor, as a model drug and assessed its encapsulation efficiency, drug release profiles, biocompatibility, and anti-inflammatory effects in vitro. Our results demonstrated the potential of PLGAM microparticles for long-term controlled local drug release in the SG. STATEMENT OF SIGNIFICANCE: SG block by locally injecting therapeutics to inhibit the activity of the sympathetic nerves provides a valuable benefit to manage chronic pain and chronic heart failure. We describe the fabrication of RBC membrane-camouflaged PLGA microparticles with cytocompatibility, hemocompatibility, and low immunogenicity, and demonstrate that they can be successfully and safely microinjected into rat SGs. The microparticle retention time within SG is over 21 days without eliciting detectable inflammation. Furthermore, we incorporate a CSF-1R inhibitor as a model drug and demonstrate the capacities of long-term drug release and regulation of macrophage functions. The strategies demonstrate the feasibility to locally microinject therapeutics loaded microparticles into SGs and pave the way for further efficacy and disease treatment evaluation.

In situ delivery of a curcumin-loaded dynamic hydrogel for the treatment of chronic peripheral neuropathy

Patients with peripheral nerve injuries would highly likely suffer from chronic neuropathic pain even after surgical intervention. The primary reasons for this involve sustained neuroinflammatory and dysfunctional changes in the nervous system after the nerve injury. We previously reported an injectable boronic ester-based hydrogel with inherent antioxidative and nerve protective properties. Herein, we first explored the anti-neuroinflammatory effects of Curcumin on primary sensory neurons and activated macrophages in vitro. Next, we incorporated thiolated Curcumin-Pluronic F-127 micelles (Cur-M) into our boronic ester-based hydrogel to develop an injectable hydrogel that serves as sustained curcumin release system (Gel-Cur-M). By orthotopically injecting the Gel-Cur-M to sciatic nerves of mice with chronic constriction injuries, we found that the bioactive components could remain on the nerves for at least 21 days. In addition, the Gel-Cur-M exhibited superior functions compared to Gel and Cur-M alone, which includes ameliorating hyperalgesia while simultaneously improving locomotor and muscular functions after the nerve injury. This could stem from in situ anti-inflammation, antioxidation, and nerve protection. Furthermore, the Gel-Cur-M also showed extended beneficial effects for preventing the overexpression of TRPV1 as well as microglial activation in the lumbar dorsal root ganglion and spinal cord, respectively, which also contributed to its analgesic effects. The underlying mechanism may involve the suppression of CC chemokine ligand-2 and colony-stimulating factor-1 in the injured sensory neurons. Overall, this study suggests that orthotopic injection of the Gel-Cur-M is a promising therapeutic strategy that especially benefits patients with peripheral neuropathy who require surgical interventions.

SERS spectroscopy with machine learning to analyze human plasma derived sEVs for coronary artery disease diagnosis and prognosis

Coronary artery disease (CAD) is one of the major cardiovascular diseases and represents the leading causes of global mortality. Developing new diagnostic and therapeutic approaches for CAD treatment are critically needed, especially for an early accurate CAD detection and further timely intervention. In this study, we successfully isolated human plasma small extracellular vesicles (sEVs) from four stages of CAD patients, that is, healthy control, stable plaque, non-ST-elevation myocardial infarction, and ST-elevation myocardial infarction. Surface-enhanced Raman scattering (SERS) measurement in conjunction with five machine learning approaches, including Quadratic Discriminant Analysis, Support Vector Machine (SVM), K-Nearest Neighbor, Artificial Neural network, were then applied for the classification and prediction of the sEV samples. Among these five approaches, the overall accuracy of SVM shows the best predication results on both early CAD detection (86.4%) and overall prediction (92.3%). SVM also possesses the highest sensitivity (97.69%) and specificity (95.7%). Thus, our study demonstrates a promising strategy for noninvasive, safe, and high accurate diagnosis for CAD early detection.

Multifunctional Microgel-Based Cream Hydrogels for Postoperative Abdominal Adhesion Prevention

Postoperative abdominal adhesions are a common problem after surgery and can produce serious complications. Current antiadhesive strategies focus mostly on physical barriers and are unsatisfactory and inefficient. In this study, we designed and synthesized advanced injectable cream-like hydrogels with multiple functionalities, including rapid gelation, self-healing, antioxidation, anti-inflammation, and anti-cell adhesion. The multifunctional hydrogels were facilely formed by the conjugation reaction of epigallocatechin-3-gallate (EGCG) and hyaluronic acid (HA)-based microgels and poly(vinyl alcohol) (PVA) based on the dynamic boronic ester bond. The physicochemical properties of the hydrogels including antioxidative and anti-inflammatory activities were systematically characterized. A mouse cecum-abdominal wall adhesion model was implemented to investigate the efficacy of our microgel-based hydrogels in preventing postoperative abdominal adhesions. The hydrogels, with a high molecular weight HA, significantly decreased the inflammation, oxidative stress, and fibrosis and reduced the abdominal adhesion formation, compared to the commercial Seprafilm group or Injury-only group. Label-free quantitative proteomics analysis demonstrated that S100A8 and S100A9 expressions were associated with adhesion formation; the microgel-containing hydrogels inhibited these expressions. The microgel-containing hydrogels with multifunctionality decreased the formation of postoperative intra-abdominal adhesions in a murine model, demonstrating promise for clinical applications.

CELL INSTANCE SEGMENTATION VIA MULTI-SCALE NON-LOCAL CORRELATION

For cell instance segmentation on Electron Microscopy (EM) images, state-of-the-art methods either conduct pixel-wise classification or follow a detection and segmentation manner. However, both approaches suffer from the enormous cell instances of EM images where cells are tightly close to each other and show inconsistent morphological properties and/or homogeneous appearances. This fact can easily lead to over-segmentation and under-segmentation problems for model prediction, i.e., falsely splitting and merging adjacent instances. In this paper, we propose a novel approach incorporating non-local correlation in the embedding space to make pixel features distinct or similar to their neighbors and thus address the over- and under-segmentation problems. We perform experiments on five different EM datasets where our proposed method yields better results than several strong baselines. More importantly, by using non-local correlation, we observe fewer false separations within one cell and fewer false fusions between cells.

A Dual-network Nerve Adhesive with Enhanced Adhesion Strength Promotes Transected Peripheral Nerve Repair

Peripheral nerve transection has a high prevalence and results in functional loss of affected limbs. The current clinical treatment using suture anastomosis significantly limits nerve recovery due to severe inflammation, secondary damage, and fibrosis. Fibrin glue, a commercial nerve adhesive as an alternative, avoids secondary damage but suffers from poor adhesion strength. To address their limitations, a highly efficacious nerve adhesive based on dual-crosslinking of dopamine-isothiocyanate modified hyaluronic acid and decellularized nerve matrix is reported in this paper. This dual-network nerve adhesive (DNNA) shows controllable gelation behaviors feasible for surgical applications, robust adhesion strength, and promoted axonal outgrowth in vitro. The in vivo therapeutic efficacy is tested using a rat-based sciatic nerve transection model. The DNNA decreases fibrosis and accelerates axon/myelin debris clearance at 10 days post-surgery, compared to suture and commercial fibrin glue treatments. At 10 weeks post-surgery, the strong adhesion and bioactivity allow DNNA to significantly decrease intraneural inflammation and fibrosis, enhance axon connection and remyelination, aid motor and sensory function recovery, as well as improve muscle contraction, compared to suture and fibrin treatments. Overall, this dual-network hydrogel with robust adhesion provides a rapid and highly efficacious nerve transection treatment to facilitate nerve repair and neuromuscular function recovery.

Integrated transcriptomic-metabolomic analysis reveals that cinnamaldehyde exposure positively regulates the phenylpropanoid pathway in postharvest Satsuma mandarin (Citrus unshiu)

Previously, wax + cinnamaldehyde (WCA) was proven to be able to effectively alleviate fruit decay and induce resistance in harvested Satsuma mandarin (Citrus unshiu). However, the potential molecular mechanism is largely unknown. In the present study, transcriptomics, metabolomics and biochemical analyses were combined to clarify this process. Transcriptomic analysis revealed that the expression of genes involved in secondary metabolites and related to pathogenesis and the phenylpropanoid pathway were significantly influenced by WCA treatment. In addition, metabolite profiling revealed that metabolites in the phenylpropanoid pathway were also predominantly impacted after WCA treatment. Correspondingly, enzymatic activities and gene expression involved in the phenylpropanoid pathway were positively regulated, especially in the first 24 h, resulting in increased levels of total phenolics, flavonoids and other secondary metabolites. Fruit inoculation experiments showed that WCA treatment significantly reduced the development of citrus green mold and sour rot while having no adverse effects on the edible quality of the tested citrus fruit. Our study confirms the potential role of WCA exposure in citrus to induce resistance through the phenylpropanoid pathway.

Privacy-preserving integration of multiple institutional data for single-cell type identification with scPrivacy

The rapid accumulation of large-scale single-cell RNA-seq datasets from multiple institutions presents remarkable opportunities for automatically cell annotations through integrative analyses. However, the privacy issue has existed but being ignored, since we are limited to access and utilize all the reference datasets distributed in different institutions globally due to the prohibited data transmission across institutions by data regulation laws. To this end, we present scPrivacy, which is the first and generalized automatically single-cell type identification prototype to facilitate single cell annotations in a data privacy-preserving collaboration manner. We evaluated scPrivacy on a comprehensive set of publicly available benchmark datasets for single-cell type identification to stimulate the scenario that the reference datasets are rapidly generated and distributed in multiple institutions, while they are prohibited to be integrated directly or exposed to each other due to the data privacy regulations, demonstrating its effectiveness, time efficiency and robustness for privacy-preserving integration of multiple institutional datasets in single cell annotations.

An Efficient Sharing Grouped Convolution via Bayesian Learning

Compared with traditional convolutions, grouped convolutional neural networks are promising for both model performance and network parameters. However, existing models with the grouped convolution still have parameter redundancy. In this article, concerning the grouped convolution, we propose a sharing grouped convolution structure to reduce parameters. To efficiently eliminate parameter redundancy and improve model performance, we propose a Bayesian sharing framework to transfer the vanilla grouped convolution to be the sharing structure. Intragroup correlation and intergroup importance are introduced into the prior of the parameters. We handle the Maximum Type II likelihood estimation problem of the intragroup correlation and intergroup importance by a group LASSO-type algorithm. The prior mean of the sharing kernels is iteratively updated. Extensive experiments are conducted to demonstrate that on different grouped convolutional neural networks, the proposed sharing grouped convolution structure with the Bayesian sharing framework can reduce parameters and improve prediction accuracy. The proposed sharing framework can reduce parameters up to 64.17%. For ResNeXt-50 with the sharing grouped convolution on ImageNet dataset, network parameters can be reduced by 96.875% in all grouped convolutional layers, and accuracies are improved to 78.86% and 94.54% for top-1 and top-5, respectively.

Exercise facilitates regeneration after severe nerve transection and further modulates neural plasticity

Patients with severe traumatic peripheral nerve injury (PNI) always suffer from incomplete recovery and poor functional outcome. Physical exercise-based rehabilitation, as a non-invasive interventional strategy, has been widely acknowledged to improve PNI recovery by promoting nerve regeneration and relieving pain. However, effects of exercise on chronic plastic changes following severe traumatic PNIs have been limitedly discussed. In this study, we created a long-gap sciatic nerve transection followed by autograft bridging in rats and tested the therapeutic functions of treadmill running with low intensity and late initiation. We demonstrated that treadmill running effectively facilitated nerve regeneration and prevented muscle atrophy and thus improved sensorimotor functions and walking performance. Furthermore, exercise could reduce inflammation at the injured nerve as well as prevent the overexpression of TRPV1, a pain sensor, in primary afferent sensory neurons. In the central nervous system, we found that PNI induced transcriptive changes at the ipsilateral lumber spinal dorsal horn, and exercise could reverse the differential expression for genes involved in the Notch signaling pathway. In addition, through neural imaging techniques, we found volumetric, microstructural, metabolite, and neuronal activity changes in supraspinal regions of interest (i.e., somatosensory cortex, motor cortex, hippocampus, etc.) after the PNI, some of which could be reversed through treadmill running. In summary, treadmill running with late initiation could promote recovery from long-gap nerve transection, and while it could reverse maladaptive plasticity after the PNI, exercise may also ameliorate comorbidities, such as chronic pain, mental depression, and anxiety in the long term.

Fabricating 3-dimensional human brown adipose microtissues for transplantation studies

Transplanting cell cultured brown adipocytes (BAs) represents a promising approach to prevent and treat obesity (OB) and its associated metabolic disorders, including type 2 diabetes mellitus (T2DM). However, transplanted BAs have a very low survival rate in vivo. The enzymatic dissociation during the harvest of fully differentiated BAs also loses significant cells. There is a critical need for novel methods that can avoid cell death during cell preparation, transplantation, and in vivo. Here, we reported that preparing BAs as injectable microtissues could overcome the problem. We found that 3D culture promoted BA differentiation and UCP-1 expression, and the optimal initial cell aggregate size was 100 μm. The microtissues could be produced at large scales via 3D suspension assisted with a PEG hydrogel and could be cryopreserved. Fabricated microtissues could survive in vivo for long term. They alleviated body weight and fat gain and improved glucose tolerance and insulin sensitivity in high-fat diet (HFD)-induced OB and T2DM mice. Transplanted microtissues impacted multiple organs, secreted protein factors, and influenced the secretion of endogenous adipokines. To our best knowledge, this is the first report on fabricating human BA microtissues and showing their safety and efficacy in T2DM mice. The proposal of transplanting fabricated BA microtissues, the microtissue fabrication method, and the demonstration of efficacy in T2DM mice are all new. Our results show that engineered 3D human BA microtissues have considerable advantages in product scalability, storage, purity, safety, dosage, survival, and efficacy.

DrSim: Similarity Learning for Transcriptional Phenotypic Drug Discovery

Transcriptional phenotypic drug discovery has achieved great success, and various compound perturbation-based data resources, such as connectivity map (CMap) and library of integrated network-based cellular signatures (LINCS), have been presented. Computational strategies fully mining these resources for phenotypic drug discovery have been proposed. Among them, the fundamental issue is to define the proper similarity between transcriptional profiles. Traditionally, such similarity has been defined in an unsupervised way. However, due to the high dimensionality and the existence of high noise in high-throughput data, similarity defined in the traditional way lacks robustness and has limited performance. To this end, we present DrSim, which is a learning-based framework that automatically infers similarity rather than defining it. We evaluated DrSim on publicly available in vitro and in vivo datasets in drug annotation and repositioning. The results indicated that DrSim outperforms the existing methods. In conclusion, by learning transcriptional similarity, DrSim facilitates the broad utility of high-throughput transcriptional perturbation data for phenotypic drug discovery. The source code and manual of DrSim are available at https://github.com/bm2-lab/DrSim/.

Application Research of IICA Algorithm in a Limited-Buffer Scheduling Problem

An improved imperialist competition algorithm (IICA) was proposed to resolve the problem of flexible flow shop scheduling that with limited buffer (LBFFSP). The IICA algorithm adds the elite personal retention strategy, reform operation and the discrete processing on the basis of ICA algorithm. This paper uses an individual selection mechanism based on Hamming distance to improve the ability of initial solution. The prospect is to use the IICA to work out related problems in cloud computing environment. The scheduling problem in the cloud-computing environment needs to consider the optimization of the completion time and cost of using cloud resources. At last, simulation tests and example tests are used to check the usefulness of improved imperialist competition algorithm in solving LBFFSP problem. Compared with standard ICA, the improved ICA has improved in the algorithm evolution process. As such, scheme 4 has a better ability to evolve, and its evolution time is greater than that of scheme 3. Scheme 5 has the best algorithm optimization performance.

Exosomes derived from differentiated human ADMSC with the Schwann cell phenotype modulate peripheral nerve-related cellular functions

Peripheral nerve regeneration remains a significant clinical challenge due to the unsatisfactory functional recovery and public health burden. Exosomes, especially those derived from mesenchymal stem cells (MSCs), are promising as potential cell-free therapeutics and gene therapy vehicles for promoting neural regeneration. In this study, we reported the differentiation of human adipose derived MSCs (hADMSCs) towards the Schwann cell (SC) phenotype (hADMSC-SCs) and then isolated exosomes from hADMSCs with and without differentiation (i.e., dExo vs uExo). We assessed and compared the effects of uExo and dExo on antioxidative, angiogenic, anti-inflammatory, and axon growth promoting properties by using various peripheral nerve-related cells. Our results demonstrated that hADMSC-SCs secreted more neurotrophic factors and other growth factors, compared to hADMSCs without differentiation. The dExo isolated from hADMSC-SCs protected rat SCs from oxidative stress and enhanced HUVEC migration and angiogenesis. Compared to uExo, dExo also had improved performances in downregulating pro-inflammatory gene expressions and cytokine secretions and promoting axonal growth of sensory neurons differentiated from human induced pluripotent stem cells. Furthermore, microRNA (miRNA) sequencing analysis revealed that exosomes and their parent cells shared some similarities in their miRNA profiles and exosomes displayed a distinct miRNA signature. Many more miRNAs were identified in dExo than in uExo. Several upregulated miRNAs, like miRNA-132-3p and miRNA-199b-5p, were highly related to neuroprotection, anti-inflammation, and angiogenesis. The dExo can effectively modulate various peripheral nerve-related cellular functions and is promising for cell-free biological therapeutics to enhance neural regeneration.

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Exosomes were isolated from hADMSCs with and without differentiation towards SC phenotype (i.e., dExo vs uExo).

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hADMSC-SCs secreted more growth factors compared to hADMSCs without differentiation.

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The dExo protected rat SCs from oxidative stress and enhanced endothelial cell migration and angiogenesis.

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dExo promoted axonal growth of sensory neurons differentiated from hiPSCs.

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miRNA sequencing analysis unveiled and compared the exosomal and cellular miRNA profiles.

State-of-the-art review of advanced electrospun nanofiber yarn-based textiles for biomedical applications

The pandemic of the coronavirus disease 2019 (COVID-19) has made biotextiles, including face masks and protective clothing, quite familiar in our daily lives. Biotextiles are one broad category of textile products that are beyond our imagination. Currently, biotextiles have been routinely utilized in various biomedical fields, like daily protection, wound healing, tissue regeneration, drug delivery, and sensing, to improve the health and medical conditions of individuals. However, these biotextiles are commonly manufactured with fibers with diameters on the micrometer scale (> 10 μm). Recently, nanofibrous materials have aroused extensive attention in the fields of fiber science and textile engineering because the fibers with nanoscale diameters exhibited obviously superior performances, such as size and surface/interface effects as well as optical, electrical, mechanical, and biological properties, compared to microfibers. A combination of innovative electrospinning techniques and traditional textile-forming strategies opens a new window for the generation of nanofibrous biotextiles to renew and update traditional microfibrous biotextiles. In the last two decades, the conventional electrospinning device has been widely modified to generate nanofiber yarns (NYs) with the fiber diameters less than 1000 nm. The electrospun NYs can be further employed as the primary processing unit for manufacturing a new generation of nano-textiles using various textile-forming strategies. In this review, starting from the basic information of conventional electrospinning techniques, we summarize the innovative electrospinning strategies for NY fabrication and critically discuss their advantages and limitations. This review further covers the progress in the construction of electrospun NY-based nanotextiles and their recent applications in biomedical fields, mainly including surgical sutures, various scaffolds and implants for tissue engineering, smart wearable bioelectronics, and their current and potential applications in the COVID-19 pandemic. At the end, this review highlights and identifies the future needs and opportunities of electrospun NYs and NY-based nanotextiles for clinical use.

3D bioprinted white adipose model for in vitro study of cancer-associated cachexia induced adipose tissue remodeling

Cancer-associated cachexia (CAC) is a complex metabolic and behavioral syndrome with multiple manifestations that involve systemic inflammation, weight loss, and adipose lipolysis. It impacts the quality of life of patients and is the direct cause of death in 20-30% of cancer patients. The severity of fat loss and adipose tissue remodeling negatively correlate with patients' survival outcomes. To address the mechanism of fat loss and design potential approaches to prevent the process, it will be essential to understand CAC pathophysiology through white adipose tissue models. In the present study, an engineered human white adipose tissue (eWAT) model based on three-dimensional (3D) bioprinting was developed and treated with pancreatic cancer cell-conditioned medium (CM) to mimic the status of CAC in vitro. We found that the CM treatment significantly increased the lipolysis and accumulation of the extracellular matrix (ECM). The 3D eWATs were further vascularized to study the influence of vascularization on lipolysis and CAC progression, which was largely unknown. Results demonstrated that CM treatment improved the angiogenesis of vascularized eWATs (veWATs), and veWATs demonstrated decreased glycerol release but increased Ucp1 expression, compared to eWATs. Many unique inflammatory cytokines (IL-8, CXCL-1, GM-CSF, etc) from the CM were detected and supposed to contribute to eWAT lipolysis, Ucp1 up-regulation, and ECM development. In response to CM treatment, eWATs also secreted inflammatory adipokines related to the metastatic ability of cancer, muscle atrophy, and vascularization (NGAL, CD54, IGFBP-2, etc). Our work demonstrated that the eWAT is a robust model for studying cachectic fat loss and the accompanying remodeling of adipose tissue. It is therefore a useful tool for future research exploring CAC physiologies and developing potential therapies.

Tri-Layered and Gel-Like Nanofibrous Scaffolds with Anisotropic Features for Engineering Heart Valve Leaflets

3D heterogeneous and anisotropic scaffolds that approximate native heart valve tissues are indispensable for the successful construction of tissue engineered heart valves (TEHVs). In this study, novel tri-layered and gel-like nanofibrous scaffolds, consisting of poly(lactic-co-glycolic) acid (PLGA) and poly(aspartic acid) (PASP), are fabricated by a combination of positive/negative conjugate electrospinning and bioactive hydrogel post-processing. The nanofibrous PLGA-PASP scaffolds present tri-layered structures, resulting in anisotropic mechanical properties that are comparable with native heart valve leaflets. Biological tests show that nanofibrous PLGA-PASP scaffolds with high PASP ratios significantly promote the proliferation and collagen and glycosaminoglycans (GAGs) secretions of human aortic valvular interstitial cells (HAVICs), compared to PLGA scaffolds. Importantly, the nanofibrous PLGA-PASP scaffolds are found to effectively inhibit the osteogenic differentiation of HAVICs. Two types of porcine VICs, from young and adult age groups, are further seeded onto the PLGA-PASP scaffolds. The adult VICs secrete higher amounts of collagens and GAGs and undergo a significantly higher level of osteogenic differentiation than young VICs. RNA sequencing analysis indicates that age has a pivotal effect on the VIC behaviors. This study provides important guidance and a reference for the design and development of 3D tri-layered, gel-like nanofibrous PLGA-PASP scaffolds for TEHV applications.

Hydrogen Peroxide Scavenging Restores N-Type Calcium Channels in Cardiac Vagal Postganglionic Neurons and Mitigates Myocardial Infarction-Evoked Ventricular Arrhythmias in Type 2 Diabetes Mellitus

Objective

Withdrawal of cardiac vagal activity is associated with ventricular arrhythmia-related high mortality in patients with type 2 diabetes mellitus (T2DM). Our recent study found that reduced cell excitability of cardiac vagal postganglionic (CVP) neurons is involved in cardiac vagal dysfunction and further exacerbates myocardial infarction (MI)-evoked ventricular arrhythmias and mortality in T2DM. However, the mechanisms responsible for T2DM-impaired cell excitability of CVP neurons remain unclear. This study tested if and how elevation of hydrogen peroxide (H2O2) inactivates CVP neurons and contributes to cardiac vagal dysfunction and ventricular arrhythmogenesis in T2DM.

Methods and Results

Rat T2DM was induced by a high-fat diet plus streptozotocin injection. Local in vivo transfection of adenoviral catalase gene (Ad.CAT) successfully induced overexpression of catalase and subsequently reduced cytosolic H2O2 levels in CVP neurons in T2DM rats. Ad.CAT restored protein expression and ion currents of N-type Ca2+ channels and increased cell excitability of CVP neurons in T2DM. Ad.CAT normalized T2DM-impaired cardiac vagal activation, vagal control of ventricular function, and heterogeneity of ventricular electrical activity. Additionally, Ad.CAT not only reduced the susceptibility to ventricular arrhythmias, but also suppressed MI-evoked lethal ventricular arrhythmias such as VT/VF in T2DM.

Conclusions

We concluded that endogenous H2O2 elevation inhibited protein expression and activation of N-type Ca2+ channels and reduced cell excitability of CVP neurons, which further contributed to the withdrawal of cardiac vagal activity and ventricular arrhythmogenesis in T2DM. Our current study suggests that the H2O2-N-type Ca2+ channel signaling axis might be an effective therapeutic target to suppress ventricular arrhythmias in T2DM patients with MI.

Regulation of Schwann Cell and DRG Neurite Behaviors within Decellularized Peripheral Nerve Matrix

Decellularized nerve hydrogels (dNHs) containing bioactive molecules are promising biomaterials for peripheral nerve injury (PNI) treatment and have been extensively applied in clinical and preclinical practice. However, most previous research projects studied their influences on nerve-related cellular behaviors in two dimensions (2D) without taking hydrogel biomechanics into consideration. The molecular mechanisms underlying the beneficial microenvironment provided by dNHs also remain unclear. In this study, dNHs from rat sciatic nerves were prepared, and their effects on Schwann cell (SC) and dorsal root ganglion (DRG) neurite behaviors were evaluated and compared to commercial rat tail type I collagen (Col) hydrogels in three-dimensional (3D) environments. We found that dNHs could promote SC proliferation and neurite outgrowth, and both the hydrogel mechanics and components contributed to the dNH functionalization. Through proteomics analysis, we found that laminin (LAM) and type V collagen (COLV) exclusively and abundantly existed in dNHs. By adding exogenous LAM and COLV into Col hydrogels, we demonstrated that they regulated SC gene expression and that LAM could promote SC spreading and neurite outgrowth, while COLV improved SC proliferation. Lastly, dNHs were fabricated into paper-like, aligned nerve scaffolds through unidirectional freezing to expand the dNH applications in PNI treatment.

Copper and palladium bimetallic sub-nanoparticles were stabilized on modified polyaniline materials as an efficient catalyst to promote C-C coupling reactions in aqueous solution

Modified polyaniline self-stabilizing Cu/Pd bimetallic sub-nanocluster composite materials (Cu/Pd@Mod-PANI-3OH) are obtained through the three steps of oxidative polymerization, structural modification, and metal self-trapping. Palladium and copper are confined and coordinated in the composite material by participating in the reaction and are highly uniformly dispersed in the carrier in the form of sub-nano clusters. The Cu/Pd@Mod-PANI-3OH micro-nano reactor catalyst formed by the self-assembly of copper, palladium and polyaniline has excellent electronic effects, including a tunable microenvironment, metal-carrier and metal-metal synergy, and the stabilizing effect of metal by polyaniline materials. It can efficiently catalyse C-C coupling (Sonogashira and Suzuki) reactions in aqueous solution with high catalytic activity and a wide range of applications (40 substrates). The characterization test results show that the Cu/Pd@Mod-PANI-3OH composite material obtained by self-trapping metal is a kind of prefabricated catalyst. During the reaction process, the high-valent metals in the pre-catalyst are in situ converted into active zero-valent metals. The catalyst's pre-fabrication strategy well protects the catalytic active centre, largely prevents agglomeration of the metal particles (can be recycled 8 times) and exhibits excellent interfacial domain-limited catalysis. The research strategy of modulation of catalytic active sites to improve the properties of materials at the molecular and atomic level reported in this article will open a new door in the research of polyaniline materials.

Electrospun conductive nanofiber yarns for accelerating mesenchymal stem cells differentiation and maturation into Schwann cell-like cells under a combination of electrical stimulation and chemical induction

Development of multifunctional tube-filling materials is required to improve the performances of the existing nerve guidance conduits (NGCs) in the repair of long-gap peripheral nerve (PN) injuries. In this study, composite nanofiber yarns (NYs) based on poly(p-dioxanone) (PPDO) biopolymer and different concentrations of carbon nanotubes (CNTs) were manufactured by utilizing a modified electrospinning apparatus. We confirmed the successful incorporation of CNTs into the PPDO nanofibers of as-fabricated composite NYs. The PPDO/CNT NYs exhibited similar morphology and structure in comparison with pure PPDO NYs. However, the PPDO/CNT NYs showed obviously enhanced mechanical properties and electrical conductivity compared to PPDO NYs. The biological tests revealed that the addition of CNTs had no negative effects on the cell growth, and proliferation of rabbit Schwann cells (rSCs), but it better maintained the phenotype of rSCs. We also demonstrated that the electrical stimulation (ES) significantly enhanced the differentiation capability of human adipose-derived mesenchymal stem cells (hADMSCs) into SC-like cells (SCLCs) on the PPDO/CNT NYs. More importantly, a unique combination of ES and chemical induction was found to further enhance the maturation of hADMSC-SCLCs on the PPDO/CNT NYs by notably upregulating the expression levels of SC myelination-associated gene markers and increasing the growth factor secretion. Overall, this study showed that our electrically conductive PPDO/CNT composite NYs could provide a beneficial microenvironment for various cell activities, making them an attractive candidate as NGC-infilling substrates for PN regeneration applications. STATEMENT OF SIGNIFICANCE: The morphology, microstructure, and bioelectrical properties of conductive PPDO/CNT NYs have been explored for guiding or controlling cell behaviors. The PPDO/CNT NYs exhibited improved mechanical properties and increased electrical conductivity compared to the CNT-free PPDO NYs. They also presented an obviously enhanced biocompatibility by effectively maintaining the phenotype of rSCs. In addition, when hADMSCs were seeded and cultured on the conductive PPDO/CNT NYs, CI was demonstrated to promote the SC-related growth factor secretion of hADMSCs, and ES was demonstrated to improve the phenotypic maturation of hADMSCs into myelinating SCLCs. Moreover, the combination of CI and ES was found to further synergistically enhance the maturation of hADMSC-SCLCs. The achievement of conductive PPDO/CNT NYs shows potential for application as NGC-infilling substrates for PN regeneration.

The effectiveness of tamsulosin hydrochloride with terazosin combination therapy for chronic prostatitis Type-III b

Objectives:

To study the therapeutic effects of combined tamsulosin hydrochloride and terazosin treatment for patients with chronic prostatitis Type-III b.

Methods:

This study involved 180 patients with chronic prostatitis Type-III b treated between January 2018 and December 2020 conducted at Nanhua Hospital Affiliated to Nanhua University. Patients were randomly divided into two equal groups: one receiving oral terazosin hydrochloride tablets only (control group), and one orally receiving both tamsulosin hydrochloride sustained-release tablets and terazosin hydrochloride tablets (observation group). Outcome measurements included symptom scoring, inflammatory cytokine levels, as well as white blood cell and lecithin body counts in the prostatic fluid.

Results:

After 30 days of treatment, the observation group showed greater treatment effectiveness (86.67% vs. 73.33%, P<0.05). QLS, USS, PS, and NIH-CPSI symptom scores were lower in the observation group than the control group (P<0.05). No differences in adverse event distribution and incidence were noted. EPS IL-2 increased more in the observation group, while PGE-2, MIP-1α, and MIP-2 decreased more in the observation group. WBC levels decreased more in the observation group, while lecithin body levels increased more in the observation group.

Conclusion:

The combination of tamsulosin hydrochloride and terazosin for the treatment of patients with chronic prostatitis Type-III b has a significant effect. This approach reduced patient symptoms, lowered inflammatory biomarkers, and generally improved quality of life. This approach appears to have clinical value worthy of future investigation.

Controllable fabrication of alginate/poly-L-ornithine polyelectrolyte complex hydrogel networks as therapeutic drug and cell carriers

Polyelectrolyte complex (PEC) hydrogels are advantageous as therapeutic agent and cell carriers. However, due to the weak nature of physical crosslinking, PEC swelling and cargo burst release are easily initiated. Also, most current cell-laden PEC hydrogels are limited to fibers and microcapsules with unfavorable dimensions and structures for practical implantations. To overcome these drawbacks, alginate (Alg)/poly-L-ornithine (PLO) PEC hydrogels are fabricated into microcapsules, fibers, and bulk scaffolds to explore their feasibility as drug and cell carriers. Stable Alg/PLO microcapsules with controllable shapes are obtained through aqueous electrospraying technique, which avoids osmotic shock and prolongs the release time. Model enzyme and nanosized cargos are successfully encapsulated and continuously released for more than 21 days. Alg/PLO PEC fibers are then prepared to encapsulate brown adipose progenitors (BAPs) and Jurkat T cells. The electrostatic interactions between Alg and PLO are found to facilitate the printability and self-support ability of Alg/PLO bioinks. Alg/PLO PEC fibers and scaffolds support cell proliferation, differentiation, and functionalization. These results demonstrate new options for biocompatible PEC hydrogel preparation and improve the understanding of PEC hydrogels as drug and cell carriers. STATEMENT OF SIGNIFICANCE: In this study, the concept of polyelectrolyte complex hydrogel networks as drug and cell carriers has been demonstrated. Their feasibility to achieve sustained drug release and cell functionality was explored, from microcapsules to fibers to three-dimension printed scaffolds. PEC microcapsules with controllable shapes were obtained. Therapeutic drugs can be encapsulated and continuously release for more than 21 days. Benefiting from the dynamic interactions of physically crosslinked PEC, self-healing fibers were achieved. Besides, the electrostatic interactions between polyelectrolytes were found to facilitate the printability and self-support ability of PEC bioinks. The PEC fibers and scaffolds with controllable structure supported cell proliferation, differentiation, and function. The outcome of current research promotes design of new biocompatible PEC hydrogels and potential drug and cell carriers.

A deep generative model for multi-view profiling of single-cell RNA-seq and ATAC-seq data

Here, we present a multi-modal deep generative model, the single-cell Multi-View Profiler (scMVP), which is designed for handling sequencing data that simultaneously measure gene expression and chromatin accessibility in the same cell, including SNARE-seq, sci-CAR, Paired-seq, SHARE-seq, and Multiome from 10X Genomics. scMVP generates common latent representations for dimensionality reduction, cell clustering, and developmental trajectory inference and generates separate imputations for differential analysis and cis-regulatory element identification. scMVP can help mitigate data sparsity issues with imputation and accurately identify cell groups for different joint profiling techniques with common latent embedding, and we demonstrate its advantages on several realistic datasets.

Wearable electronics for skin wound monitoring and healing

Wound healing is one of the most complex processes in the human body, supported by many cellular events that are tightly coordinated to repair the wound efficiently. Chronic wounds have potentially life-threatening consequences. Traditional wound dressings come in direct contact with wounds to help them heal and avoid further complications. However, traditional wound dressings have some limitations. These dressings do not provide real-time information on wound conditions, leading clinicians to miss the best time for adjusting treatment. Moreover, the current diagnosis of wounds is relatively subjective. Wearable electronics have become a unique platform to potentially monitor wound conditions in a continuous manner accurately and even to serve as accelerated healing vehicles. In this review, we briefly discuss the wound status with some objective parameters/biomarkers influencing wound healing, followed by the presentation of various novel wearable devices used for monitoring wounds and accelerating wound healing. We further summarize the associated device working principles. This review concludes by highlighting some major challenges in wearable devices toward wound healing that need to be addressed by the research community.