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Carbon monoxide (CO) produced in many large-scale industrial oxidation processes is difficult to separate from nitrogen (N₂), and afterward, CO is further oxidized to carbon dioxide. Here, we report a soft nanoporous crystalline material that selectively adsorbs CO with adaptable pores, and we present crystallographic evidence that CO molecules can coordinate with copper(II) ions. The unprecedented high selectivity was achieved by the synergetic effect of the local interaction between CO and accessible metal sites and a global transformation of the framework. This transformable crystalline material realized the separation of CO from mixtures with N₂, a gas that is the most competitive to CO. The dynamic and efficient molecular trapping and releasing system is reminiscent of sophisticated biological systems such as heme proteins.

Human learners can generalize a new concept from a small number of samples. In contrast, conventional machine learning methods require large amounts of data to address the same types of problems. Humans have cognitive biases that promote fast learning. Here, we developed a method to reduce the gap between human beings and machines in this type of inference by utilizing cognitive biases. We implemented a human cognitive model into machine learning algorithms and compared their performance with the currently most popular methods, naïve Bayes, support vector machine, neural networks, logistic regression and random forests. We focused on the task of spam classification, which has been studied for a long time in the field of machine learning and often requires a large amount of data to obtain high accuracy. Our models achieved superior performance with small and biased samples in comparison with other representative machine learning methods.

An artificial receptor for proMMP‐9 was created by fusing tissue inhibitor of MMP‐1 (TIMP‐1) with type II transmembrane mosaic serine protease (MSP‐T1). Expression of MSP‐T1 in 293T cells induced binding of proMMP‐9, which was processed by MMP‐2 activated by membrane type 1 MMP (MT1‐MMP). HT1080 cells transfected with the MSP‐T1 gene produced activated MMP‐9 in collagen gel, and addition of proMMP‐2 to the culture augmented it, which resulted in intensive collagen digestion. These cells metastasized into chick embryonic liver more than control cells. Treatment of HT1080 cells with concanavalin A in the presence of exogenous proMMP‐2 induced activation of not only proMMP‐2 but also proMMP‐9. Knockdown of MT1‐MMP or TIMP‐2 expression with siRNA suppressed activation of both proMMP‐2 and proMMP‐9. Transfection of TIMP‐1 siRNA suppressed cell binding and activation of proMMP‐9, but not proMMP‐2 activation. Knockdown of a disintegrin and metalloproteinase 10 (ADAM10) expression reduced cell binding and processing of proMMP‐9. These results suggest that proMMP‐9, which binds to a receptor complex containing TIMP‐1 and ADAM10, is activated by the MT1‐MMP/MMP‐2 axis, and MMP‐9 thus activated stimulates cellular proteolysis and metastasis. ProMMP‐9 which binds to a receptor complex containing TIMP‐1 and ADAM10 is activated by MT1‐MMP/MMP‐2 axis. MMP‐9 thus activated stimulates cellular proteolysis and metastasis.

Membrane‐type matrix metalloproteinase‐1 (MT1‐MMP) mediates cleavage of not only MMP‐2/gelatinase A for activation, but also a variety of substrates including type I collagen (reviewed in Cancer Sci 2005; 96: 212–7). MMP‐2 activation involves tissue inhibitor of MMP (TIMP)‐2 as a bridging molecule between MT1‐MMP and pro‐MMP‐2. Thus, net activity of MT1‐MMP and MMP‐2 is regulated in a complex manner depending on TIMP‐2 concentration. During invasive growth of tumor cells in type I collagen matrix, MT1‐MMP initiates denaturation of collagen into gelatin, which is subsequently digested further by MMP‐2 adjacent to MT1‐MMP. Coordinate action of MT1‐MMP and MMP‐2 may facilitate pericellular proteolysis, and enhance not only tumor invasion/migration but also cell growth. Tetraspanins as binding proteins of MT1‐MMP regulate MT1‐MMP subcellular localization and compartmentalization, leading to efficient MMP‐2 activation and proteolysis coupled with cellular function. (Cancer Sci 2010; 101: 843–847)

BackgroundThe real-world efficacy, prognostic factors, and adverse events of second-line nivolumab monotherapy and subsequent third-line therapy for unresectable or metastatic esophageal cancer have not been fully evaluated.MethodsThis multi-institutional retrospective cohort study evaluated 184 consecutive patients treated with second-line nivolumab monotherapy for esophageal cancer between March 2021 and December 2022. We assessed tumor response, adverse events, long-term survival, and prognostic factors.ResultsAmong 128 patients with measurable lesions, the response rate was 23% and the disease control rate for all enrolled patients was 45%. The incidence of grade 3 or higher adverse events was 14%, but no treatment-related deaths presented. Median progression-free survival was 5.1 months and overall survival was 14 months, respectively. C-reactive protein level and performance status were identified as significant prognostic factors of overall survival through Cox proportional hazards analysis. The group with two favorable prognostic factors showed better overall survival than the groups with either one or zero prognostic factors (median overall survival: 22, 15, and 4.4 months, respectively). Among 69 patients who received third-line taxane anticancer agents, the progression-free survival was 6.7 months.ConclusionsOur study demonstrated that the real-world outcomes of second-line nivolumab monotherapy were comparable to those of previous randomized clinical trials in terms of tumor response, safety, and long-term survival. Furthermore, a good performance status and low C-reactive protein levels may identify patients who are likely to benefit from therapy. Third-line chemotherapy after nivolumab treatment may have an enhanced effect; however, further prospective studies are required to confirm this finding.

The development of a new methodology for visualizing and detecting gases is imperative for various applications. Here, we report a novel strategy in which gas molecules are detected by signals from a reporter guest that can read out a host structural transformation. A composite between a flexible porous coordination polymer and fluorescent reporter distyrylbenzene (DSB) selectively adsorbed CO 2 over other atmospheric gases. This adsorption induced a host transformation, which was accompanied by conformational variations of the included DSB. This read-out process resulted in a critical change in DSB fluorescence at a specific threshold pressure. The composite shows different fluorescence responses to CO 2 and acetylene, compounds that have similar physicochemical properties. Our system showed, for the first time, that fluorescent molecules can detect gases without any chemical interaction or energy transfer. The host–guest coupled transformations play a pivotal role in converting the gas adsorption events into detectable output signals. Methodologies capable of directly visualizing and detecting gases are important for a wide variety of applications that involve instantaneous decision-making in complex environments and locations. A strategy for the capture and detection of gases by co-operative structural transformations of a flexible porous coordination polymer and fluorescent reporter molecules is now reported.

Photochromic molecules have shown much promise as molecular components of stimuli-responsive materials, but despite recent achievements in various photoresponsive materials, quantitative conversion in photochemical reactions in solids is hampered by the lack of intrinsic structural flexibility available to release stress and strain upon photochemical events. This issue remains one of the challenges in developing solid-state photoresponsive materials. Here, we report a strategy to realize photoresponsive crystalline materials showing quantitative reversible photochemical reactions upon ultraviolet and visible light irradiation by introducing structural flexibility into crystalline porous frameworks with a twofold interpenetration composed of a diarylethene-based ligand. The structural flexibility of the porous framework enables highly efficient photochemical electrocyclization in a single-crystal-to-single-crystal manner. CO 2 sorption on the porous crystal at 195 K is reversibly modulated by light irradiation, and coincident X-ray powder diffraction/sorption measurements clearly demonstrate the flexible nature of the twofold interpenetrated frameworks. Organizing photochromic molecules into 3D networks is a key strategy to access photoresponsive materials, but framework rigidity typically limits conversion efficiency. Here, the authors exploit a flexible metal-organic framework to achieve quantitative and reversible photoisomerization in a porous crystalline solid.

We show that for a projective toric manifold with the ample second Chern character, if there exists a Fano contraction, then it is isomorphic to the projective space. For the case that the second Chern character is nef, the Fano contraction gives either a projective line bundle structure or a direct product structure. We also show that, for a toric weakly 2-Fano manifold, there does not exist a divisorial contraction to a point.

Porous compounds are ubiquitous and indispensable in daily life as adsorbents and catalysts. The discovery of a new porous compound with unique properties based on intrinsic nanosized space and surface functionalities is scientifically and technologically important. However, the functional species used in this context are limited to those that are sufficiently inert to not spoil the porous structures. Here, we show a new strategy to achieve a crystalline porous material with the pore surface regularly decorated with highly reactive ‘bare’ nitrenes that are photonically generated from stable ‘dormant’ precursors at will. The bare triplet nitrenes were accessible to and reacted with adsorbed oxygen or carbon monoxide molecules, which showed not only activation of the pore surface, but also a high probability of chemical trapping and conversion of guest molecules by light stimulation on demand. Nanoscale porous materials show unique properties that can be important for catalytic, separation and gas-storage applications. A strategy to yield crystalline porous compounds decorated with reactive nitrenes that can chemically trap and convert guest molecules by light stimulation is now reported.

Increased central venous pressure in congestive heart failure causes renal dysfunction; however, the underlying mechanisms are unclear. We created a rat renal congestion model and investigated the effect of renal congestion on hemodynamics and molecular mechanisms. The inferior vena cava (IVC) between the renal veins was ligated by suture in male Sprague-Dawley rats to increase upstream IVC pressure and induce congestion in the left kidney only. Left kidney congestion reduced renal blood flow, glomerular filtration rate, and increased renal interstitial hydrostatic pressure. Tubulointerstitial and glomerular injury and medullary thick ascending limb hypoxia were observed only in the congestive kidneys. Molecules related to extracellular matrix expansion, tubular injury, and focal adhesion were upregulated in microarray analysis. Renal decapsulation ameliorated the tubulointerstitial injury. Electron microscopy captured pericyte detachment in the congestive kidneys. Transgelin and platelet-derived growth factor receptors, as indicators of pericyte-myofibroblast transition, were upregulated in the pericytes and the adjacent interstitium. With the compression of the peritubular capillaries and tubules, hypoxia and physical stress induce pericyte detachment, which could result in extracellular matrix expansion and tubular injury in renal congestion.