Engineering of Cas12a nuclease variants with enhanced genome-editing specificity.

The clustered regularly interspaced short palindromic repeat (CRISPR)-Cas12a system is a powerful tool in gene editing; however, crRNA-DNA mismatches might induce unwanted cleavage events, especially at the distal end of the PAM. To minimize this limitation, we engineered a hyper fidelity AsCas12a variant carrying the mutations S186A/R301A/T315A/Q1014A/K414A (termed HyperFi-As) by modifying amino acid residues interacting with the target DNA and crRNA strand. HyperFi-As retains on-target activities comparable to wild-type AsCas12a (AsCas12aWT) in human cells. We demonstrated that HyperFi-As has dramatically reduced off-target effects in human cells, and HyperFi-As possessed notably a lower tolerance to mismatch at the position of the PAM-distal region compared with the wild type. Further, a modified single-molecule DNA unzipping assay at proper constant force was applied to evaluate the stability and transient stages of the CRISPR/Cas ribonucleoprotein (RNP) complex. Multiple states were sensitively detected during the disassembly of the DNA-Cas12a-crRNA complexes. On off-target DNA substrates, the HyperFi-As-crRNA was harder to maintain the R-loop complex state compared to the AsCas12aWT, which could explain exactly why the HyperFi-As has low off-targeting effects in human cells. Our findings provide a novel version of AsCas12a variant with low off-target effects, especially capable of dealing with the high off-targeting in the distal region from the PAM. An insight into how the AsCas12a variant behaves at off-target sites was also revealed at the single-molecule level and the unzipping assay to evaluate multiple states of CRISPR/Cas RNP complexes might be greatly helpful for a deep understanding of how CRISPR/Cas behaves and how to engineer it in future.

Engineering of a compact, high-fidelity EbCas12a variant that can be packaged with its crRNA into an all-in-one AAV vector delivery system.

The CRISPR-associated endonuclease Cas12a has become a powerful genome-editing tool in biomedical research due to its ease of use and low off-targeting. However, the size of Cas12a severely limits clinical applications such as adeno-associated virus (AAV)-based gene therapy. Here, we characterized a novel compact Cas12a ortholog, termed EbCas12a, from the metagenome-assembled genome of a currently unclassified Erysipelotrichia. It has the PAM sequence of 5'-TTTV-3' (V = A, G, C) and the smallest size of approximately 3.47 kb among the Cas12a orthologs reported so far. In addition, enhanced EbCas12a (enEbCas12a) was also designed to have comparable editing efficiency with higher specificity to AsCas12a and LbCas12a in mammalian cells at multiple target sites. Based on the compact enEbCas12a, an all-in-one AAV delivery system with crRNA for Cas12a was developed for both in vitro and in vivo applications. Overall, the novel smallest high-fidelity enEbCas12a, this first case of the all-in-one AAV delivery for Cas12a could greatly boost future gene therapy and scientific research.

Decoding the transcriptional heterogeneity, differentiation lineage, clinical significance in tissue-resident memory CD8 T cell of the small intestine by single-cell analysis.

Resident memory T (Trm) cells which are specifically located in non-lymphoid tissues showed distinct phenotypes and functions compared to circulating memory T cells and were vital for the initiation of robust immune response within tissues. However, the heterogeneity in the transcriptional features, development pathways, and cancer response of Trm cells in the small intestine was not demonstrated. Here, we integrated scRNA-seq and scTCR-seq data pan-tissue T cells to explore the heterogeneity of Trm cells and their development pathways. Trm were enriched in tissue-specific immune response and those in the DUO specially interacted with B cells via TNF and MHC-I signatures. T cell lineage analyses demonstrated that Trm might be derived from the T_CD4/CD8 subset within the same organ or migrated from spleen and mesenteric lymph nodes. We compared the immune repertoire of Trm among organs and implied that clonotypes in both DUO and ILE were less expanded and hydrophilic TRB CDR3s were enriched in the DUO. We further demonstrated that Trm in the intestine infiltrated the colorectal cancer and several effector molecules were highly expressed. Finally, the TCGA dataset of colorectal cancer implied that the infiltration of Trm from the DUO and the ILE was beneficial for overall survival and the response to immune checkpoint blockade.

A Biomimetic Fibrous Composite Scaffold with Nanotopography-Regulated Mineralization for Bone Defect Repair.

The effective regeneration of large bone defects via bone tissue engineering is challenging due to the difficulty in creating an osteogenic microenvironment. Inspired by the fibrillar architecture of the natural extracellular matrix, we developed a nanoscale bioengineering strategy to produce bone fibril-like composite scaffolds with enhanced osteogenic capability. To activate the surface for biofunctionalization, self-adaptive ridge-like nanolamellae were constructed on poly(ε-caprolactone) (PCL) electrospinning scaffolds via surface-directed epitaxial crystallization. This unique nanotopography with a markedly increased specific surface area offered abundant nucleation sites for Ca2+ recruitment, leading to a 5-fold greater deposition weight of hydroxyapatite than that of the pristine PCL scaffold under stimulated physiological conditions. Bone marrow mesenchymal stem cells (BMSCs) cultured on bone fibril-like scaffolds exhibited enhanced adhesion, proliferation, and osteogenic differentiation in vitro. In a rat calvarial defect model, the bone fibril-like scaffold significantly accelerated bone regeneration, as evidenced by micro-CT, histological histological and immunofluorescence staining. This work provides the way for recapitulating the osteogenic microenvironment in tissue-engineered scaffolds for bone repair.

Fetal growth restriction exhibits various mTOR signaling in different regions of mouse placentas with altered lipid metabolism.

Fetal growth restriction (FGR) is a common complication of pregnancy and can have significant impact on obstetric and neonatal outcomes. Increasing evidence has shown that the inhibited mechanistic target of rapamycin (mTOR) signaling in placenta is associated with FGR. However, interpretation of existing research is limited due to inconsistent methodologies and varying understanding of the mechanism by which mTOR activity contributes to FGR. Hereby, we have demonstrated that different anatomic regions of human and mouse placentas exhibited different levels of mTOR activity in normal compared to FGR pregnancies. When using the rapamycin-induced FGR mouse model, we found that placentas of FGR pregnancies exhibited abnormal morphological changes and reduced mTOR activity in the decidual-junctional layer. Using transcriptomics and lipidomics, we revealed that lipid and energy metabolism was significantly disrupted in the placentas of FGR mice. Finally, we demonstrated that maternal physical exercise during gestation in our FGR mouse model was associated with increased fetal and placental weight as well as increased placental mTOR activity and lipid metabolism. Collectively, our data indicate that the inhibited placental mTOR signaling contributes to FGR with altered lipid metabolism in mouse placentas, and maternal exercise could be an effective method to reduce the occurrence of FGR or alleviate the adverse outcomes associated with FGR.

Targeting myeloperoxidase to stabilize unruptured aneurysm: an imaging-guided approach.

Inflammation plays a key role in pathogenesis and rupture of aneurysms. Non-invasively and dynamically monitoring aneurysm inflammation is critical. This study evaluated myeloperoxidase (MPO) as an imaging biomarker and therapeutic target for aneurysm inflammation using an elastase-induced rabbit model treated with or without 4-aminobenzoic acid hydrazide (ABAH), an irreversible inhibitor of MPO. Myeloperoxidase-sensitive magnetic resonance imaging (MRI) using Mn-TyrEDTA, a peroxidase activity-dependent contrast agent, revealed weak contrast enhancement in contralateral arteries and decreased contrast enhancement in aneurysm walls with ABAH treatment, indicating MPO activity decreased and inflammation mitigated. This was supported by reduced immune cell infiltration, matrix metalloproteinases (MMP-2 and - 9) activity, ROS production and arterial wall destruction on histology. Finally, the aneurysm expansion rate remained < 50% throughout the study in the ABAH(+) group, but increased gradually in the ABAH(-) group. Our results suggest that inhibition of MPO attenuated inflammation and expansion of experimental aneurysm and MPO-sensitive MRI showed promise as a noninvasive tool for monitoring aneurysm inflammation.

Factors associated with stress among pregnant women with a second child in Hunan province under China's two-child policy: a mixed-method study.

OBJECTIVE: The purpose of the study was to investigate the status of pregnancy stress and to explore factors associated with pregnancy stress among women by China's two-child policy. METHODS: A mixed-method study involving both quantitative and qualitative methods was conducted using questionnaires and semi-structured interviews. The questionnaires encompassed socio-demographic and obstetric characteristics, as well as the Pregnancy Stress Rating Scale (PSRS) and the Social Support Rating Scale (SSRS). Initially, the participants were required to complete the questionnaires, enabling us to assess their respective pregnancy stress statuses. Subsequently, we selectively interviewed pregnant women with a second child and exhibited at least mild pregnancy stress. The qualitative study sought to uncover the factors contributing to their stress during pregnancy. RESULTS: A total of 463 subjects were enrolled; of the subjects, 22 (4.8%) had no stress, 407 (87.9%) had mild stress, 34 (7.3%) had moderate stress. Generalized linear regression analysis revealed significant factors (P<0.05) related to pregnancy stress, including family financial burden, subjective support, fertility desire, gender of the first child, and gender preference. Additionally, 16 subjects were interviewed, and through analysis, three major themes emerged, each comprising 12 sub-themes associated with pregnancy stress. These themes were identified as fertility factors (worry about maternal and child health, birth experience, and parenting stress), family factors ( financial burden, second child care problems, first child's acceptance of the second child, family concerns, fertility desire, and gender preference) and social factors (involving life events, career development and workload). CONCLUSION: The diver factors contribute to pregnancy stress among pregnant women under China's two-child policy. Our study could be used to develop appropriate interventions to reduce pregnancy stress and to enhance the mental health of women pregnant with a second child.

Structures suggest an approach for converting weak self-peptide tumor antigens into superagonists for CD8 T cells in cancer.

Tumors frequently express unmutated self-tumor-associated antigens (self-TAAs). However, trial results using self-TAAs as vaccine targets against cancer are mixed, often attributed to deletion of T cells with high-affinity receptors (TCRs) for self-TAAs during T cell development. Mutating these weak self-TAAs to produce higher affinity, effective vaccines is challenging, since the mutations may not benefit all members of the broad self-TAA-specific T cell repertoire. We previously identified a common weak murine self-TAA that we converted to a highly effective antitumor vaccine by a single amino acid substitution. In this case the modified and natural self-TAAs still raised very similar sets of CD8 T cells. Our structural studies herein show that the modification of the self-TAA resulted in a subtle change in the major histocompatibility complex I-TAA structure. This amino acid substitution allowed a dramatic conformational change in the peptide during subsequent TCR engagement, creating a large increase in TCR affinity and accounting for the efficacy of the modified self-TAA as a vaccine. These results show that carefully selected, well-characterized modifications to a poorly immunogenic self-TAA can rescue the immune response of the large repertoire of weakly responding natural self-TAA-specific CD8 T cells, driving them to proliferate and differentiate into functional effectors. Subsequently, the unmodified self-TAA on the tumor cells, while unable to drive this response, is nevertheless a sufficient target for the CD8 cytotoxic effectors. Our results suggest a pathway for more efficiently identifying variants of common self-TAAs, which could be useful in vaccine development, complementing other current nonantigen-specific immunotherapies.

Assessment of Left Ventricular Longitudinal Systolic Function Using Global Tissue Motion Annular Displacement in Patients with Chronic Severe Aortic Regurgitation.

Background: In patients with chronic aortic regurgitation (AR), the left ventricle (LV) develops compensatory mechanisms to sustain its function. LV global longitudinal strain (GLS) is a key means to detect subclinical LV dysfunction, even when LV ejection fraction (LVEF) remains within the normal range. Compared to GLS, Tissue motion annular displacement (TMAD) is a simpler strain-based method to assess LV systolic function. This study investigated the correlation among TMAD parameters, LVEF, and GLS, and determined the diagnostic value and threshold of TMAD parameters for left ventricular systolic dysfunction. Methods: A prospective study was conducted at a single center. The case and control groups consisted of patients with chronic severe AR and healthy volunteers, respectively. Speckle-tracking echocardiography (STE) was used to assess the GLS and TMAD parameters in the apical 4-chamber and apical 2-chamber. Subsets of participants were analyzed for inter- and intra-observer variability and analysis time. A correlation analysis was performed among the TMAD parameters, LVEF, and GLS. Receiver operating characteristic curves and the area under the curves (AUCs) were used to evaluate the predictive value of the TMAD parameters for LVEF <50% and GLS > -18%. Results: This study involved 96 patients with severe chronic AR and 45 healthy volunteers. Compared to GLS, TMAD demonstrated superior intra- and inter-observer consistency and shorter average analysis time. Biplane global Midpt% showed the highest correlation with GLS and LVEF among all the TMAD parameters, with r values of 0.81 and 0.74, respectively. Furthermore, global Midpt% had AUCs of 0.89 and 0.92 for predicting LVEF< 50% and GLS > -18%, respectively. Conclusion: The TMAD global Midpt% has the potential to replace GLS in clinical practice and find wide applications.

Factors associated with discontinuation in fertility treatment: a systematic scoping review.

PURPOSE: The discontinuation of fertility treatment could decrease the chances of achieving parenthood for infertile patients and often leads to economic loss and medical resource waste. However, the evidence on the factors associated with discontinuation is unclear and inconsistent in the context of fertility treatment. This scoping review aimed to summarize the evidence on factors associated with discontinuation in fertility treatment, identify the current knowledge gap, and generate recommendations for future research. METHODS: We searched PubMed, Embase, The Cochrane Library, Web of Science, CINAHL, American Psychological Association, and http://clinicaltrials.gov from inception to June 2023 without language or time restrictions. We also searched the grey literature in Open Grey and Google Scholar and hand-searched the reference lists of relevant studies to identify potentially eligible studies. Publications that studied factors associated with discontinuation in fertility treatment were included. The identified factors were mapped to the World Health Organization's treatment adherence model. RESULTS: Thirty-seven articles involving 41,973 infertile patients from 13 countries were included in this scoping review. All studies identified the factors from the perspective of patients, except for one that described the factors from the healthcare providers' perspective. A total of 42 factors were identified, with most of them belonging to the patient-related dimension, followed by socio-economic-related, treatment-related, condition-related, and healthcare system-related dimensions. Female education level, social support, and insurance coverage decreased the likelihood of treatment discontinuation, whereas multiparous women, male infertility, depression, higher infertility duration, and treatment duration increased the likelihood of treatment discontinuation. Age, education level, and ethnicity are the commonly nonmodifiable factors for treatment discontinuation, while insurance coverage, depression, and anxiety symptoms are among some of the more commonly reported modifiable factors. CONCLUSION: This is the first scoping review examining and synthesizing evidence on the factors influencing of discontinuation in fertility treatment. This review could inform researchers, clinicians, and policymakers to address modifiable barriers and facilitators to develop personalized and multicomponent interventions that could improve the discontinuation in fertility treatment.

Regulatory emotional self-efficacy and self-compassion mediate anxiety, depression, body image distress and subjective well-being in women with polycystic ovary syndrome: A cross-sectional study.

AIMS: This study aims to investigate the mediating role of regulatory emotional self-efficacy and self-compassion in the relationship among anxiety, depression, body image distress and subjective well-being among women with polycystic ovary syndrome. DESIGN: A cross-sectional study. METHODS: The study recruited 510 women with polycystic ovary syndrome from a tertiary hospital affiliated with a university in Hunan Province, China. The study employed several tools to collect data, including the Generalized Anxiety Scale, the Patient Health Questionnaire-9, the Body Image States Scale, the Self-Compassion Scale, the Regulatory Emotional Self-Efficacy Scale and the Index of Well-being questionnaire. Data analysis was carried out using descriptive analysis, spearman correlation analysis, ordinary least squares regression and bootstrapping. RESULTS: The study's findings indicate that regulatory emotional self-efficacy and self-compassion both act as mediators in the connection between anxiety, depression, body image distress and subjective well-being among women with polycystic ovary syndrome. CONCLUSION: The study emphasizes the significance of regulatory emotional self-efficacy and self-compassion in promoting well-being among women with polycystic ovary syndrome. It also implies that interventions targeted at enhancing these factors could potentially enhance the subjective well-being of women affected by PCOS. IMPACT: Our study's primary contribution is to underscore the crucial mediating roles of regulatory emotional self-efficacy and self-compassion in the relationship among anxiety, depression, body image distress and subjective well-being. Our study indicates that clinical practitioners should prioritize improving the regulatory emotional self-efficacy and self-compassion of women with polycystic ovary syndrome, reducing their anxiety, depression and body image distress and improving their subjective well-being. REPORTING METHOD: This study was reported according to the Standards for Reporting Qualitative Research (SRQR). PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution outside of participation in the actual study for purposes of data collection.

Effects of different proportions of fruit tree branches on nicotine content and microbial diversity during composting of tobacco waste.

Adding fruit tree branches to the compost pile in appropriate proportions is one of the methods used to address the challenge of tobacco waste recycling. However, the effects of different proportions of fruit tree branches on nicotine concentration and microbial diversity during tobacco waste composting have not been reported. In this study, a composting system with tobacco waste, cow dung, and fruit tree branches was established in a laboratory fermenter to assess the impact of adding 10%, 20%, and 30% fruit tree branches on quantity changes. In addition, the relationships between nicotine degradation, compost properties, enzyme activities, and microbial diversities were determined using biochemical assay methods and high-throughput sequencing. The results showed that adding appropriate proportions of fruit branch segments affected changes in physical and chemical properties during composting and promoted tobacco waste compost maturity. Aerobic composting effectively degraded nicotine in tobacco waste. Increased proportions of fruit branch segments led to elevations in nicotine degradation rates and enzyme activities related to lignocellulose degradation. The addition of fruit branches influenced the relative abundance and species of dominant bacteria and fungi at the phylum and genus levels. However, it did not significantly affect the relative abundance of the main bacterial genera involved in nicotine degradation. Nevertheless, it reduced the sensitivity of enzyme activity to nicotine content within heaps, increasing reliance on total nitrogen changes. The results of this study provide a theoretical basis for the utilization of tobacco waste in composting systems and indicate that fruit tree branches can enhance nicotine degradation efficiency during tobacco waste composting.

Genome-wide identification and systematic analysis of the HD-Zip gene family and its roles in response to pH in Panax ginseng Meyer.

BACKGROUND: Ginseng, Panax ginseng Meyer, is a traditional herb that is immensely valuable both for human health and medicine and for medicinal plant research. The homeodomain leucine zipper (HD-Zip) gene family is a plant-specific transcription factor gene family indispensable in the regulation of plant growth and development and plant response to environmental stresses. RESULTS: We identified 117 HD-Zip transcripts from the transcriptome of ginseng cv. Damaya that is widely grown in Jilin, China where approximately 60% of the world's ginseng is produced. These transcripts were positioned to 64 loci in the ginseng genome and the ginseng HD-Zip genes were designated as PgHDZ genes. Identification of 82 and 83 PgHDZ genes from the ginseng acc. IR826 and cv. ChP genomes, respectively, indicated that the PgHDZ gene family consists of approximately 80 PgHDZ genes. Phylogenetic analysis showed that the gene family originated after Angiosperm split from Gymnosperm and before Dicots split from Monocots. The gene family was classified into four subfamilies and has dramatically diverged not only in gene structure and functionality but also in expression characteristics. Nevertheless, co-expression network analysis showed that the activities of the genes in the family remain significantly correlated, suggesting their functional correlation. Five hub PgHDZ genes were identified that might have central functions in ginseng biological processes and four of them were shown to be actively involved in plant response to environmental pH stress in ginseng. CONCLUSIONS: The PgHDZ gene family was identified from ginseng and analyzed systematically. Five potential hub genes were identified and four of them were shown to be involved in ginseng response to environmental pH stress. The results provide new insights into the characteristics, diversity, evolution, and functionality of the PgHDZ gene family in ginseng and lay a foundation for comprehensive research of the gene family in plants.

Patients with metastatic renal cell carcinoma who receive immune-targeted therapy may derive survival benefit from nephrectomy.

BACKGROUND: Nephrectomy, whether in the era of cytokine therapy or targeted therapy, has an important role in the treatment of metastatic renal cell carcinoma. With the advent of immunotherapy, immunotherapy combined with targeted therapy has become the mainstream of systemic therapy, but the role of nephrectomy in metastatic renal cell carcinoma is unclear. In this study, we retrospectively analyzed the impact of nephrectomy on survival in patients with metastatic renal cell carcinoma who received immune-targeted therapy. METHODS: Patients with metastatic renal cell carcinoma who received immune-targeted therapy at three centers between May 17, 2019 and August 1, 2022 were collected, who were divided into two groups based on whether nephrectomy was performed or not. Survival, response rate and adverse event were compared between the two groups. The primary end point was progression free survival, Subgroup analysis and univariate and multivariable prognostic analyses were also assessed. RESULTS: With a median follow-up time of 29.3 months (95% CI 28.5-30.2), 165 patients were recruited and divided into two groups based on whether they underwent nephrectomy or not. There were 68 patients in the non-nephrectomy group, 97 in the nephrectomy group. Compared to patients treated with immune-targeted therapy, patients treated with immune-targeted therapy plus nephrectomy were able to achieve survival benefits, with a median PFS of 10.8 months (95% CI 8.3-13.3) and 14.4 months (95% CI 12.6-16.2), respectively, as well as an HR of 0.476 (95% CI 0.323-0.701, p = 0.0002). The 12-month and 18-month PFS rates were 30.9% versus 60.8% and 7.4% versus 25.8%, respectively. The objective response rate (ORR) was 52.9% and 60.8%, respectively, in the non-nephrectomy and nephrectomy groups (p = 0.313), and the disease control rate (DCR) was 75% and 83.5%, respectively (p = 0.179). The most common adverse events related to treatment were hypothyroidism, immune-related pneumonitis and rash. Multivariate analysis showed that primary tumor nephrectomy prior to immune-targeted therapy, clear cell renal carcinoma and oligo metastasis were independent prognostic factors. CONCLUSIONS: Nephrectomy may provide PFS benefit with tolerable safety for patients with metastatic renal cell carcinoma who receive immune-targeted therapy. In multivariate analysis, nephrectomy, clear cell carcinoma, and oligo-organ metastasis were found to be favorable independent prognostic factors.

Myeloperoxidase-Sensitive Magnetic Resonance Imaging Assesses Inflammatory Activation State in Experimental Mouse Acute Gout.

BACKGROUND: A novel myeloperoxidase-activatable manganese-based (MPO-Mn) MRI probe may enable the activation state of inflammatory foci to be detected and monitored noninvasively. PURPOSE: To evaluate the inflammatory response in a mouse model of acute gout using MPO as an imaging biomarker and a potential therapeutic target. STUDY TYPE: Prospective. ANIMAL MODEL: A total of 40 male Swiss mice with monosodium urate crystals induced acute gout. FIELD STRENGTH/SEQUENCE: A 3.0 T/T1-weighted imaging with 2D fast spoiled gradient recalled echo and T2-weighted imaging with fast recovery fast spin-echo sequences. ASSESSMENT: The difference in contrast-to-noise ratio between left hind limb (lesion) and right hind limb (internal reference) (ΔCNR), and normalized signal-to-noise ratio (nSNR) on the right hind limb were calculated and compared. The expression level and activity of myeloperoxidase (MPO) were analyzed using western blotting and spectrophotometric quantitation activity assay. MPO-positive cell infiltration and lesion volume were evaluated using immunofluorescence staining and T2-weighted images, respectively. STATISTICAL TESTS: Student's t test. A P-value less than 0.05 was considered to be statistically significant. RESULTS: MPO-Mn resulted in a significantly higher ΔCNR than Gd-DTPA (22.54 ± 1.86 vs. 13.90 ± 2.22) but lower nSNR on the reference right hind limb (1.08 ± 0.07 vs. 1.21 ± 0.08). Compared to the nontreatment group, MPO-inhibition resulted in a significantly reduced contrast enhancement at the lesion (17.81 ± 1.58 vs. 22.96 ± 3.12), which was consistent with a remission of the inflammatory response, as evidenced by a substantial reduction of lesion volume (0.55 ± 0.16 mm3 /g vs. 1.14 ± 0.15 mm3 /g), myeloperoxidase expression level (0.98 ± 0.09 vs. 1.48 ± 0.19) and activity (0.75 ± 0.12 vs. 1.12 ± 0.07), and inflammatory cell recruitment. DATA CONCLUSION: MPO-Mn MRI has potential to evaluate the activation state of inflammatory foci in the experimental model of acute gout. EVIDENCE LEVEL: 1. TECHNICAL EFFICACY: Stage 1.

Near-infrared (NIR) imaging with indocyanine green (ICG) may assist in intraoperative decision making and improving surgical margin in bone and soft tissue tumor surgery.

BACKGROUND AND OBJECTIVES: Negative surgical margins are significant in improving patient outcomes. However, surgeons can only rely on visual and tactile information to identify tumor margins intraoperatively. We hypothesized that intraoperative fluorescence imaging with indocyanine green (ICG) could serve as an assistive technology to evaluate surgical margins and guide surgery in bone and soft tissue tumor surgery. METHODS: Seventy patients with bone and soft tissue tumors were enrolled in this prospective, non-randomized, single-arm feasibility study. All patients received intravenous indocyanine green (0.5 mg/kg) before surgery. Near-infrared (NIR) imaging was performed on in situ tumors, wounds, and ex vivo specimens. RESULTS: 60/70 tumors were fluorescent at NIR imaging. The final surgical margins were positive in 2/55 cases, including 1/40 of the sarcomas. Surgical decisions were changed in 19 cases by NIR imaging, and in 7/19 cases final pathology demonstrated margins were improved. Fluorescence analysis showed that the tumor-to-background ratio (TBR) of primary malignant tumors was higher than that of benign, borderline, metastatic, and tumors ≥5 cm in size had higher TBR than those <5 cm. CONCLUSIONS: ICG fluorescence imaging may be a beneficial technique to assist in surgical decision making and improving surgical margins in bone and soft tissue tumor surgery.

Mn-Activated Fluoride Phosphors Modified by Surfactant with Outstanding Water Resistance and Luminescent Thermal Properties.

Although Mn4+-activated fluoride phosphors have high luminescence quality, their poor water resistance and thermal fluorescence properties significantly limit their practical applications. Here, we propose a surfactant modification strategy by adding the surfactant cetyltrimethylammonium bromide (CTAB) to the synthesis and modifying the surface of the phosphor with ethylene diamine tetraacetic acid (EDTA) to obtain a phosphor with excellent luminescence thermal properties and water resistance, K2TiF6:Mn4+-xCTAB-EDTA (KTFM-xC-E) phosphors. The experimental and X-ray diffraction Rietveld refinement results confirm that the phosphor has higher structural rigidity and thus improved thermal stability. The surface modification with EDTA resulted in the formation of a dilute Mn4+ shell layer on the phosphor surface, which prevented the inward hydrolysis of the phosphor and resulted in excellent water resistance. Therefore, we have successfully modified K2TiF6:Mn4+ (KTFM) phosphors using low-cost surfactants, which also provides new ideas for other commercial high-quality phosphors.

Luminescence Enhancement of K2LiAlF6:Mn4+ Phosphors by Zn2+-Mediated Charge Compensation for Fast-Response Backlighting Applications.

Wide-spectrum displays require narrow-band red phosphors activated by Mn4+, but most of them, such as K2SiF6:Mn4+, have long fluorescence decay lifetimes (>7 ms) that hinder their use in fast-response backlights. Interestingly, K2LiAlF6:0.05Mn4+ has a shorter fluorescence lifetime (3.43 ms), but its disadvantage is that its luminescence intensity is relatively weak. So, in this study, the luminescence intensity of K2LiAlF6:0.05Mn4+ is improved by doping with Zn2+. The experimental results show that enhancement of the luminous intensity is as high as 39%, the fluorescence lifetime is only increased by 13% (3.89 ms), and it is still less than 4 ms. Through experiments and differential charge density calculations, it has been revealed that the luminescence intensity improvement is due to an increased crystalline quality during the synthesis process. Specifically, the co-doping of Zn2+ reduces the formation of impurity ions Mn2+ and Mn3+ and the generation of K+ vacancies caused by nonequivalent doping. We demonstrate the advantage of this phosphor over K2SiF6:Mn4+ in terms of response speed by using a camera. It emits only weak red light after the blue chip stops working for 5 ms, indicating its potential application in next-generation fast-response displays.

Theoretical Study on Spectrum and Luminescence Mechanism of Cy5.5 and Cy7.5 Dye Based on Density Functional Theory (DFT).

Cy5.5 and 7.5 are the most commonly used NIR 2-region fluoresceins, which have good luminescence properties and important biomedical tracer applications. In this paper, their molecular non-covalent interactions, UV-Vis absorption spectra, main bond lengths, electrostatic potential distributions, frontier molecular orbitals (HOMO and LUMO) and energy gaps were calculated by density functional theory (DFT). We found that the differences in the luminescence properties and energy gaps of Cy5.5 and Cy7.5 molecules may be caused by the length of the conjugated chains between the two aromatic rings in the molecule. By calculating the relevant molecular characteristics, this paper can provide ideas and theoretical basis for the relevant modification and application, as well as the development of new fluorescent dyes.

Based on the IWATE criteria: to investigate the influence of different surgical approaches on the perioperative outcomes of hepatectomy.

BACKGROUND: In terms of perioperative outcomes, compared with traditional open surgery and laparoscopic surgery, studies of robotic liver resection have been limited and must be further clarified. METHODS: Clinical data from 465 patients who underwent liver resection were collected in this retrospective study, and the IWATE criteria were used to evaluate the difficulty level of each operation. We compared perioperative outcomes of open, laparoscopic, or robotic approaches for patients with uncomplicated and complex hepatectomy according to different IWATE scores. Among patients with uncomplicated hepatectomy, the median operation time was significantly longer in the robotic liver resection (RLR) group than in the open liver resection (OLR) and laparoscopic liver resection (LLR) groups; however, the RLR group had the shortest hospital stay. There were no significant differences in intraoperative blood loss, conversion rate, total complication rate, or serious complication rate among the three groups. RESULTS: Among patients with complex hepatectomy, the RLR group had the smallest intraoperative blood loss and shortest mean length of stay. The cases converted to open hepatectomy were lower in the RLR group than in the laparoscopic group, mainly based on the IWATE score of expert hepatectomy. The incidence of general and serious postoperative complications in the RLR group was significantly lower than that in the OLR and LLR groups. CONCLUSIONS: Robotic liver resection is a safe and feasible surgical method that is more advantageous than laparoscopic and open liver resection, especially in complex liver surgery.