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关键词： evolution of co‐   operation   natural selection   simulation   theory  

摘要： A fundamental task of evolutionary biology is to explain the pervasive impression of organismal design in nature, including traits benefiting kin. Inclusive fitness is considered by many to be a crucial piece in this puzzle, despite ongoing discussion about its scope and limitations. Here, we use individual-based simulations to study what quantity (if any) individual organisms become adapted to maximize when genetic architectures are more or less suitable for the presumed main driver of biological adaptation, namely cumulative multi-locus evolution. As an expository device, we focus on a hypothetical situation called Charlesworth's paradox, in which altruism is seemingly predicted to evolve, yet altruists immediately perish along with their altruistic genes. Our results support a recently proposed re-definition of inclusive fitness, which is concerned with the adaptive design of whole organisms as shaped by multi-locus evolution, rather than with selection for any focal gene. They also illustrate how our conceptual understanding of adaptation at the phenotypic level should inform our choice of genetic assumptions in abstract simplified models.

关键词： ancient architectures   deep learning   GAN   image inpainting   routine inspection   segmentation  

摘要： Ancient architectures have a lot of distinctive patterns on their component surfaces. But due to the wind and the Sun, the patterns will present extensive deficiencies, which are not conducive to the routine inspections and the subsequent repair work. To overcome these limits, an automatic deep learning-based method of segmentation, inpainting, and classification for defective patterns on ancient architecture is proposed. First, You Only Look At CoefficienTs, which is a real-time instance segmentation network, is applied to obtain the mask of the defective parts. Then Generative Image Inpainting with Contextual Attention, which is an image inpainting algorithm, is used to reconstruct the defective parts. Finally, Residual Neural Network-50 is used to classify the reconstructed images. In this paper, three types of dragon motifs in the Forbidden City were studied. The results show that the classification accuracy of the reconstructed images is increased by an average of 13.1%, with the maximum increasing by 23.5%. The proposed methods can prepare for future routine inspections in advance.

关键词： Recombination   Transgenesis   Delivery   loxP   Conditional   MEF   EC  

摘要： Cre-loxP recombination system is a powerful tool for genome engineering. One of its applications is found in genetic mouse models that often require to induce Cre recombination in preimplantation embryos. Here, we describe a technically simple, affordable and highly efficient protocol for Cre protein delivery into mouse zygotes by electroporation. We show that electroporation based delivery of Cre has no negative impact on embryo survival and the method can be easily combined with in vitro fertilization resulting in a significantly faster generation of desired models. Lastly, we demonstrate that Cre protein electroporation is suitable for allelic conversion in primary cells derived from conditional mouse models.

摘要： OBJECTIVE Insulin icodec (icodec) is a novel once-weekly basal insulin analog. This trial investigated two approaches for switching to icodec versus once-daily insulin glargine 100 units/mL (IGlar U100) in people with type 2 diabetes receiving daily basal insulin and one or more oral glucose-lowering medications. RESEARCH DESIGN AND METHODS This multicenter, open-label, treat-to-target phase 2 trial randomized (1:1:1) eligible basal insulin-treated (total daily dose 10-50 units) people with type 2 diabetes (HbA(1c) 7.0-10.0% [53.0-85.8 mmol/mol]) to icodec with an initial 100% loading dose (in which only the first dose was doubled [icodec LD]), icodec with no loading dose (icodec NLD), or IGlar U100 for 16 weeks. Primary end point was percent time in range (TIR;3.9-10.0 mmol/L [70-180 mg/dL]) during weeks 15 and 16, measured using continuous glucose monitoring. Key secondary end points included HbA(1c), adverse events (AEs), and hypoglycemia. RESULTS Estimated mean TIR during weeks 15 and 16 was 72.9% (icodec LD;n = 54), 66.0% (icodec NLD;n = 50), and 65.0% (IGlar U100;n = 50), with a statistically significant difference favoring icodec LD versus IGlar U100 (7.9%-points [95% CI 1.8-13.9]). Mean HbA(1c) reduced from 7.9% (62.8 mmol/mol) at baseline to 7.1% (54.4 mmol/mol icodec LD) and 7.4% (57.6 mmol/mol icodec NLD and IGlar U100);incidences and rates of AEs and hypoglycemic episodes were comparable. CONCLUSIONS Switching from daily basal insulin to once-weekly icodec was well tolerated and provided effective glycemic control. Loading dose use when switching to once-weekly icodec significantly increased percent TIR during weeks 15 and 16 versus once-daily IGlar U100, without increasing hypoglycemia risk.

关键词： artificial antigen-presenting cells   cancer immunotherapy   intracellular hydrogelation   radical polymerization   T-cell expansion  

摘要： The growing enthusiasm for cancer immunotherapies and adoptive cell therapies has prompted increasing interest in biomaterials development mimicking natural antigen-presenting cells (APCs) for T-cell expansion. In contrast to conventional bottom-up approaches aimed at layering synthetic substrates with T-cell activation cues, transformation of live dendritic cells (DCs) into artificial APCs (aAPCs) is demonstrated herein using a facile and minimally disruptive hydrogelation technique. Through direct intracellular permeation of poly(ethylene glycol) diacrylate (PEG-DA) hydrogel monomer and UV-activated radical polymerization, intracellular hydrogelation is rapidly accomplished on DCs with minimal influence on cellular morphology and surface antigen display, yielding highly robust and modular cell-gel hybrid constructs amenable to peptide antigen exchange, storable by freezing and lyophilization, and functionalizable with cytokine-releasing carriers for T-cell modulation. The DC-derived aAPCs are shown to induce prolonged T-cell expansion and improve anticancer efficacy of adoptive T-cell therapy in mice compared to nonexpanded control T cells, and the gelation technique is further demonstrated to stabilize primary DCs derived from human donors. The work presents a versatile approach for generating a new class of cell-mimicking biomaterials and opens new venues for immunological interrogation and immunoengineering.

关键词： protease   glucose   PAR2   tissue factor   kidney tubular epithelial cells   diabetes  

摘要： Coagulopathies common to patients with diabetes and chronic kidney disease (CKD) are not fully understood. Fibrin deposits in the kidney suggest the local presence of clotting factors including tissue factor (TF). In this study, we investigated the effect of glucose availability on the synthesis of TF by cultured human kidney tubular epithelial cells (HTECs) in response to activation of protease-activated receptor 2 (PAR2). PAR2 activation by peptide 2f-LIGRLO-NH2 (2F, 2 mu M) enhanced the synthesis and secretion of active TF (similar to 45 kDa) which was blocked by a PAR2 antagonist (I-191). Treatment with 2F also significantly increased the consumption of glucose from the cell medium and lactate secretion. Culturing HTECs in 25 mM glucose enhanced TF synthesis and secretion over 5 mM glucose, while addition of 5 mM 2-deoxyglucose (2DOG) significantly decreased TF synthesis and reduced its molecular weight (similar to 40 kDa). Blocking glycosylation with tunicamycin also reduced 2F-induced TF synthesis while reducing its molecular weight (similar to 36 kDa). In conclusion, PAR2-induced TF synthesis in HTECs is enhanced by culture in high concentrations of glucose and suppressed by inhibiting either PAR2 activation (I-191), glycolysis (2DOG) or glycosylation (tunicamycin). These results may help explain how elevated concentrations of glucose promote clotting abnormities in diabetic kidney disease. The application of PAR2 antagonists to treat CKD should be investigated further.

关键词： Stem cell   Acid   Acidity   Pluripotency   Pluripotent   Zinc   SSEA-4   Oct4  

摘要： Environmental changes can stress and alter biology at the molecular and cellular level. For example, metal-protein interaction is a classic physic and biological property of nature, which is fundamentally influenced by acidity. Here, we report a unique cellular reprogramming phenomenon in that a brief strong acid treatment induced the expression of pluripotent stem cell (PSC) markers. We used strong acid to briefly challenge mix-cultured gastric cells, and then subcultured survived cells in a normal cell culture medium. We found that survival acid-treated cells expressed PSC markers detected by commonly used pluripotent antibodies such as SSEA-4 and Oct4. In addition, we observed that the survived cells from the acid challenge grew faster during the second and third weeks of subculture and had a relative short doubling time (DT) than the controls. PSC marker-labeled 'older' cells also presented immature cell-like morphology with some having marker Oct4 in the nucleus. Finally, the expression of the markers appeared to be sensitive to metal ion chelation. Removal of the metals during a brief acid treatment reduced pluripotent marker-positive cells, suggesting the dissociation of metals from metal-binding proteins may be a factor involved in the induction of stem cell markers. Our findings reveal that somatic cells appear to possess a plasticity feature to express pluripotent marker proteins or to select cell subpopulations that express pluripotent marker proteins when cells are transiently exposed to strong acid. It opens new directions for understanding conserved regulatory mechanisms involved in cellular survival under stressful stimulation.

关键词： Neuroendocrine neoplasm   Neuroendocrine carcinoma   Mixed neuroendocrine   non-neuroendocrine neoplasm   Urinary bladder  

摘要： Neuroendocrine carcinomas (NECs) of the urinary bladder are very rare and can be observed in the context of mixed neuroendocrine/non-neuroendocrine neoplasms (MiNENs), most frequently in association with urothelial carcinoma. Small cell NECs are far more common than large cell NECs (LCNECs), which are exceedingly rare. We describe a primary MiNEN of the urinary bladder, composed of a LCNEC and of an adenocarcinoma, in which the neuroendocrine component reached complete pathological regression after neoadjuvant M-VAC chemotherapy, whereas the non-neuroendocrine component of the tumor progressed to metastatic disease. Compared to mixed neuroendocrine/non-neuroendocrine neoplasms described in the literature until now, this appears to be a unique case that expands the spectrum of neuroendocrine neoplasia of the urinary bladder.

关键词： peptidesparasitedisulfidepeptide chemical synthesisautoimmune diseasecolitisprotein structure  

摘要： The prevalence of autoimmune diseases is on the rise globally. Currently, autoimmunity presents in over 100 different forms and affects around 9% of the world's population. Current treatments available for autoimmune diseases are inadequate, expensive, and tend to focus on symptommanagement rather than cure. Clinical trials have shown that live helminthic therapy can decrease chronic inflammation associated with inflammatory bowel disease and other gastrointestinal autoimmune inflammatory conditions. As an alternative and better controlled approach to live infection, we have identified and characterized two peptides, Acan1 and Nak1, from the excretory/secretory component of parasitic hookworms for their therapeutic activity on experimental colitis. WesynthesizedAcan1 andNak1 peptides fromthe Ancylostoma caninum and Necator americanus hookworms and assessed their structures and protective properties in human cell-based assays and in a mouse model of acute colitis. Acan1 and Nak1 displayed anticolitic properties via significantly reducing weight loss and colon atrophy, edema, ulceration, and necrosis in 2,4,6-trinitrobenzene sulfonic acid-exposed mice. These hookworm peptides prevented mucosal loss of goblet cells and preserved intestinal architecture. Acan1 upregulated genes responsible for the repair and restitution of ulcerated epithelium, whereas Nak1 downregulated genes responsible for epithelial cell migration and apoptotic cell signaling within the colon. These peptides were nontoxic and displayed key immunomodulatory functions in human peripheral blood mononuclear cells by suppressing CD4(+) T cell proliferation and inhibiting IL-2 and TNF production. We conclude that Acan1 and Nak1 warrant further development as therapeutics for the treatment of autoimmunity, particularly gastrointestinal inflammatory conditions.

关键词： extremely low frequency pulsed electromagnetic fields (ELF-PEMFs)   mesenchymal stem cells   bone healing   cigarette smoke extract   TGF-beta signaling   primary cilium  

摘要： Cigarette smoking (CS) is one of the main factors related to avoidable diseases and death across the world. Cigarette smoke consists of numerous toxic compounds that contribute to the development of osteoporosis and fracture nonunion. Exposure to pulsed electromagnetic fields (PEMF) was proven to be a safe and effective therapy to support bone fracture healing. The aims of this study were to investigate if extremely low frequency (ELF-) PEMFs may be beneficial to treat CS-related bone disease, and which effect the duration of the exposure has. In this study, immortalized human mesenchymal stem cells (SCP-1 cells) impaired by 5% cigarette smoke extract (CSE) were exposed to ELF-PEMFs (16 Hz) with daily exposure ranging from 7 min to 90 min. Cell viability, adhesion, and spreading were evaluated by Sulforhodamine B, Calcein-AM staining, and Phalloidin-TRITC/Hoechst 33342 staining. A migration assay kit was used to determine cell migration. Changes in TGF-beta signaling were evaluated with an adenoviral Smad2/3 reporter assay, RT-PCR, and Western blot. The structure and distribution of primary cilia were analyzed with immunofluorescent staining. Our data indicate that 30 min daily exposure to a specific ELF-PEMF most effectively promoted cell viability, enhanced cell adhesion and spreading, accelerated migration, and protected TGF-beta signaling from CSE-induced harm. In summary, the current results provide evidence that ELF-PEMF can be used to support early bone healing in patients who smoke.