Unlocking Diverse π-Bond Enrichment Frameworks by the Synthesis and Conversion of Boronated Phenyldiethynylethylenes.

The π-bond enrichment frameworks not only serve as a crucial building block in organic synthesis but also assume a pivotal role in the fields of materials science, biomedicine, photochemistry, and other related disciplines owing to their distinctive structural characteristics. The incorporation of various substituents into the C═C double bonds of tetrasubstituted alkenes is currently a highly significant research area. However, the synthesis of tetrasubstituted alkenes with diverse substituents on double bonds poses a significant challenge in achieving stereoselectivity. Here, we reported an efficient and convergent route of Cu-catalyzed borylalkynylation of both symmetrical and unsymmetrical 1,3-diynes, B2pin2, and acetylene bromide to the construction of boronated phenyldiethynylethylene (BPDEE) derivatives with excellent chemo-, stereo-, and regioselectivities. BPDEE derivatives could transform into novel tetrasubstituted organic π-conjugated gem-diphenyldiethynylethylene (DPDEE), vinylphenyldiethynylethylene (VPDEE), and phenyltriethynylethylene (PTEE) derivatives by a stepwise process, which provides a flexible platform for the synthesis of complex π-bond enrichment frameworks that were difficult to synthesize by previous methods. The initial optical characterization revealed that the synthesized molecules exhibited aggregation-induced emission (AIE) properties, which further establishes the groundwork for future applications and enriches and advances the field of functional π-conjugated frameworks research.

Chemo-, regio- and stereoselective access to polysubstituted 1,3-dienes via Nickel-catalyzed four-component reactions.

1,2-Difunctionalization of alkynes offers a straightforward approach to access polysubstituted alkenes. However, simultaneous multi-component cascade transformations including difunctionalization of two alkynes with both syn- and anti-selectivity in one catalyst system is undeveloped and proves to be a significant challenge. Herein, we report a Nickel-catalyzed four-component reaction to access polysubstituted 1,3-dienes using two terminal alkynes, aryl boroxines, and perfluoroalkyl iodides, wherein the reaction forms three new C-C bonds in a single vessel and serve as a modular strategy to access polysubstituted 1,3-dienes with excellent chemoselectivity, good regioselectivity and exclusive stereoselectivity. Control experiments reveal the plausible reaction mechanism and DFT calculations explain the cause for the formation of this unusual four-component reaction. Furthermore, we successfully incorporate two biologically active units into 1,2,3,4-tetrasubstituted 1,3-dienes, which greatly increases the diversity of molecular scaffolds and brings more potential values to medicinal chemistry, the synthetic utility of our protocol is further demonstrated by the late-stage transformations.

Difluorocarbene-Enabled Synthesis of 3-Alkenyl-2-oxindoles from ortho-Aminophenylacetylenes.

Herein, we report a transition-metal-free [4 + 1] cyclization pathway from difluorocarbene and ortho-amino aryl alkynone, rendering an effective and universal strategy for the construction of 3-alkenyl-2-oxindoles. Our strategy starts from cheap and accessible ortho-amino aryl alkynone instead of the direct indole skeleton; moreover, in situ generated difluorocarbene from commercially available halogenated difluoroalkylative reagents enables the cleavage of a C-N bond and formation of new C-N bonds and C-C bonds.

The development and validation of pathological sections based U-Net deep learning segmentation model for the detection of esophageal mucosa and squamous cell neoplasm.

Background: Deep learning methods have demonstrated great potential for processing high-resolution images. The U-Net model, in particular, has shown proficiency in the segmentation of biomedical images. However, limited research has examined the application of deep learning to esophageal squamous cell carcinoma (ESCC) segmentation. Therefore, this study aimed to develop deep learning segmentation systems specifically for ESCC. Methods: A Visual Geometry Group (VGG)-based U-Net neural network architecture was utilized to develop the segmentation models. A pathological image cohort of surgical specimens was used for model training and internal validation, with two additional endoscopic biopsy section cohort for external validation. Model efficacy was evaluated across several metrics including Intersection over Union (IOU), accuracy, positive predict value (PPV), true positive rate (TPR), specificity, dice similarity coefficient (DSC), area under the receiver operating characteristic curve (AUC), and F1-Score. Results: Surgical samples from ten patients were analyzed retrospectively, with each biopsy section cohort encompassing five patients. Transfer learning models based on U-Net weights yielded optimal results. For mucosa segmentation, the in internal validation achieved 93.81% IOU, with other parameters exceeding 96% (96.96% accuracy, 96.45% PPV, 96.65% TPR, 98.41% specificity, 96.81% DSC, 96.11% AUC, and 96.55% F1-Score). The tumor segmentation model attained an IOU of 91.95%, along with other parameters surpassing 95% (95.90% accuracy, 95.62% PPV, 95.71% TPR, 97.88% specificity, 95.81% DSC, 94.92% AUC, and 95.67% F1-Score). In the external validation for tumor segmentation model, IOU was 59.86% for validation database 1 (72.74% for accuracy, 76.03% for PPV, 77.17% for TPR, 83.80% for specificity, 74.89% for DSC, 71.83% for AUC, and 76.60% for F1-Score), and 50.88% for validation cohort 2 (68.03% for accuracy, 59.02% for PPV, 66.87% for TPR, 78.48% for specificity, 67.44% for DSC, 64.68% for AUC, and 62.70% for F1-Score). Conclusions: The models exhibited satisfactory results, paving the way for their potential deployment on standard computers and integration with other artificial intelligence models in clinical practice in the future. However, limited to the size of study, the generalizability of models is impaired in the external validation, larger pathological section cohort would be needed in future development to ensure robustness and generalization.

Mechanisms and characteristics of subcapsular sinus macrophages in tumor immunity: a narrative review.

Background and Objective: Lymph nodes constitute an integral component of the secondary lymphoid organs, housing a diverse population of macrophages. Macrophages exhibit heterogeneity in terms of localization, phenotype and ontogeny. Recent evidence has established that subcapsular sinus macrophages (SCSMs) are the initial cells exposed to antigens from afferent lymph vessels, playing a crucial role in the host immune response against invading pathogens and tumor cells. In order to summarize the role and mechanisms of SCSM in tumor immunity, this study systematically reviews research on SCSMs in tumor immunity. Methods: A systematic search was conducted in PubMed and Web of Science to identify articles investigating clinical significance and mechanisms of SCSMs. Study eligibility was independently evaluated by two authors based on the assessment of titles, abstracts and full-texts. Key Content and Findings: The narrative review included a total of 17 studies. Previous research consistently showed that a high level of SCSM in patients with various carcinomas is associated with a favorable long-term prognosis. SCSM acts as the front-line defender in antitumor activity, engaging in intricate communication with other immune cells. Moreover, SCSM could directly and indirectly modulate tumor immunity, and the integrity of SCSM layer is interrupted in disease status. Several studies explored the feasibility of targeting SCSM to activate immunity against tumors. However, the direct molecular interactions and alternation in signal pathway in the tumor immunity of SCSM are less well established in previous researches. Conclusions: This narrative review underscores the critical role of SCSM in tumor immunity. Future studies should focus on the deeper mechanism underlying SCSMs and explore their clinical applications.

The relationship between soluble CD73 and the incidence of septic shock in severe sepsis patients: a cross-sectional analysis of data from a prospective FINNAKI study.

Background: Sepsis is a leading cause of mortality worldwide. Septic shock is a subtype of sepsis in which the underlying cardiovascular and cellular/metabolic disorders are profound enough to increase mortality significantly. We sought to investigate the association between soluble cluster of differentiation-73 (sCD73) and the incidence of septic shock in severe sepsis patients. Methods: This cross-sectional study included 588 Finnish patients with severe sepsis or septic shock from the Finnish Acute Kidney Injury (FINNAKI) study. The primary exposure of interest was baseline level of sCD73. The outcome was the incidence of septic shock. Multivariable logistic regression analyses were performed to assess the independent association between sCD73 and the incidence of septic shock. Results: The average age of 588 participants was 62±16 years, and 65.14% of the patients were male. The average sCD73 was 5.11 (interquartile range, 3.30, 8.25) ng/mL. The incidence of sepsis shock was 429 (72.96%). In the multivariate logistic regression model, sCD73 was negatively associated with septic shock. After multiple adjustments (for age, gender, lactate, the Sequential Organ Failure Assessment score, systolic heart failure, emergency admission, operative admission, and acute kidney injury within 12 h), a 1 ng/mL increment in sCD73 was associated with a 5% lower incidence of septic shock [odds ratio (OR) =0.95; 95% confidence interval (CI): 0.92, 0.98; P<0.001]. Conclusions: We found that sCD73 was negatively correlated with septic shock. Higher sCD73 was associated with a lower incidence of septic shock. Keywords: Septic shock; severe sepsis; soluble cluster of differentiation-73 (sCD73); inflammation; phosphatidylinositol 3-kinase/Akt signaling (PI3K/Akt signaling).

Photo-induced trifunctionalization of bromostyrenes via remote radical migration reactions of tetracoordinate boron species.

Tetracoordinate boron species have emerged as radical precursors via deboronation by photo-induced single electron transfer (SET) pathway. These reactions usually produce an alkyl radical and boron-bound species, and the valuable boron species are always discarded as a by-product. Given the importance of boron species, it will be very attractive if the two parts could be incorporated into the eventual products. Herein we report a photo-catalyzed strategy in which in situ generated tetracoordinated boron species decomposed into both alkyl radicals and boron species under visible light irradiation, due to the pre-installation of a vinyl group on the aromatic ring, the newly generated alkyl radical attacks the vinyl group while leaving the boron species on ipso-position, then both radical part and boron moiety are safely incorporated into the final product. Tertiary borons, secondary borons, gem-diborons as well as 1,2-diborons, and versatile electrophiles are all well tolerated under this transformation, of note, ortho-, meta- and para-bromostyrenes all demonstrated good capabilities. The reaction portraits high atom economy, broad substrate scope, and diversified valuable products with tertiary or quaternary carbon center generated, with diborons as substrates, Csp2-B and Csp3-B are established simultaneously, which are precious synthetic building blocks in chemical synthesis.

Injectable conductive hydrogel can reduce pacing threshold and enhance efficacy of cardiac pacemaker.

Background: Pacemaker implantation is currently used in patients with symptomatic bradycardia. Since a pacemaker is a lifetime therapeutic device, its energy consumption contributes to battery exhaustion, along with its voltage stimulation resulting in local fibrosis and greater resistance, which are all detrimental to patients. The possible resolution for those clinical issues is an injection of a conductive hydrogel, poly-3-amino-4-methoxybenzoic acid-gelatin (PAMB-G), to reduce the myocardial threshold voltage for pacemaker stimulation. Methods: PAMB-G is synthesized by covalently linking PAMB to gelatin, and its conductivity is measured using two-point resistivity. Rat hearts are injected with gelatin or PAMB-G, and pacing threshold is evaluated using electrocardiogram and cardiac optical mapping. Results: PAMB-G conductivity is 13 times greater than in gelatin. The ex vivo model shows that PAMB-G significantly enhances cardiac tissue stimulation. Injection of PAMB-G into the stimulating electrode location at the myocardium has a 4 times greater reduction of pacing threshold voltage, compared with electrode-only or gelatin-injected tissues. Multi-electrode array mapping reveals that the cardiac conduction velocity of PAMB-G group is significantly faster than the non- or gelatin-injection groups. PAMB-G also reduces pacing threshold voltage in an adenosine-induced atrial-ventricular block rat model. Conclusion: PAMB-G hydrogel reduces cardiac pacing threshold voltage, which is able to enhance pacemaker efficacy.

A conductive cell-delivery construct as a bioengineered patch that can improve electrical propagation and synchronize cardiomyocyte contraction for heart repair.

Cardiac tissue engineering is of particular importance in the combination of contracting cells with a biomaterial scaffold, which serves as a cell-delivery construct, to replace cardiomyocytes (CMs) that are lost as a result of an infarction, to restore heart function. However, most biomaterial scaffolds are nonconductive and may delay regional conduction, potentially causing arrhythmias. In this study, a conductive CM-delivery construct that consists of a gelatin-based gelfoam that is conjugated with a self-doped conductive polymer (poly-3-amino-4-methoxybenzoic acid, PAMB) is proposed as a cardiac patch (PAMB-Gel patch) to repair an infarcted heart. A nonconductive plain gelfoam (Gel patch) is used as a control. The electrical conductivity of the PAMB-Gel patch is approximately 30 times higher than that of the Gel patch; as a result, the conductive PAMB-Gel patch can substantially increase electrical conduction between distinct clusters of beating CMs, facilitating their synchronous contraction. In vivo epicardial implantation of the PAMB-Gel patch that is seeded with CMs (the bioengineered patch) in infarcted rat hearts can significantly enhance electrical activity in the fibrotic tissue, improving electrical impulse propagation and synchronizing CM contraction across the scar region, markedly reducing its susceptibility to cardiac arrhythmias. Echocardiography shows that the bioengineered conductive patch has an important role in the restoration of cardiac function, perhaps owing to the synergistic effects of its conductive construct and the synchronously beating CMs. These experimental results reveal that the as-proposed bioengineered conductive patch has great potential for repairing injured cardiac tissues.

Does Early Graft Patency Benefit from Perioperative Statin Therapy? A Propensity Score-Matched Study of Patients Undergoing Off-Pump Coronary Artery Bypass Surgery.

BACKGROUND: Decreased graft patency after off-pump coronary artery bypass grafting (OPCAB) leads to substantial increases in cardiac events. However, there is paucity of data on efficacy and safety of perioperative statin therapy for OPCAB populations. METHODS: 582 patients undergoing OPCAB in a single-institution database (October 1, 2009-September 30, 2012) were stratified by perioperative continuation of statin therapy (CS group, n=398) or not (DS group, n=184). Inverse probability weighted propensity adjustment was used to account for treatment assignment bias, resulting in a well-matched cohort. Primary outcomes were graft patency at an average of five days after operation and in-hospital mortality. Secondary outcomes included intraoperative blood loss, liver, and renal functions. RESULTS: No in-hospital death occurred in this study. Early graft patency rates after OPCAB were 98.4% (1255 of 1275 grafts) in the CS group and 98.0% (583 of 595 grafts, P=0.486) in the DS group. Secondary outcomes showed a reduction in blood loss during operation (438.53 mL versus 480.47 mL, P=0.01). Continuation of statin therapy is associated with alanine transaminase (ALT) elevation (49.67 U/L versus 34.52 U/L, P<0.001), as well as aspartate transaminase (33.54 U/L versus 28.10 U/L, P<0.001). Abnormal ALT elevation was observed in 8.9% of the CS group and 3.1% in DS (odds ratio 3.06, 95% confidence interval, 1.77 to 5.29, P<0.001). There was no significant difference in estimated glomerular filtration rate (76.28 mL/min/1.73m2 versus 76.13 mL/min/1.73m2, P=0.90). Subgroup analyses suggested that graft occlusion was less common in CS than in DS group among smoking patients (odds ratio 0.41, 95% confidence interval, 0.20 to 0.86, P=0.026). CONCLUSIONS: Perioperative continuation of statin therapy did not improve early graft patency in OPCAB patients. A lower risk of graft occlusion was observed among smoking patients. Continuous statin use correlated with liver function elevation (Clinical Trials.gov number, NCT01268917).

Mitral valve annuloplasty versus replacement for severe ischemic mitral regurgitation.

Although practice guidelines recommend surgery for patients with severe chronic ischemic mitral regurgitation (CIMR), they do not specify whether to repair or replace the mitral valve. 436 consecutive patients with severe CIMR were eligible for inclusion in the study, of which 316 (72.5%) underwent mitral valve annuloplasty (MVA) whereas 120 (27.5%) received mitral valve replacement (MVR). At 59 months (interquartile range, 37-85 months) follow-up, though the left ventricle end-diastolic diameter was markedly larger (P = 0.019) in the MVA group than in the MVR group, no significant difference was observed in overall survival, freedom from cardiac death, or avoidance of major adverse cardiac or cerebrovascular events (MACCE). MVA provides better results in freedom from cardiac death in subgroups of age ≥65years and left ventricular ejection fraction (EF) ≥50% (P = 0.014 and P = 0.016, respectively), whereas MVR was associated with a lower risk of MACCE in subgroups of age <65years, EF <50% and left ventricular inferior basal wall motion abnormality (BWMA) (all P < 0.05). In conclusion, MVR is a suitable management of patients with severe CIMR, and it is more favorable to ventricular remodeling. The choice of MVA or MVR should depend on major high-risk clinical factors.