Rapid and mass manufacturing of soft hydrogel microstructures for cell patterns assisted by 3D printing

Micro-/nano-patterns on hydrogels are widely used in cell patterning.However,manufacturing molds with traditional lithography is time-consuming and expensive.In addition,the excessive demolding force can easily damage patterns since biocompatible hydrogels are ultra-soft or brittle.Here,we presented a novel method for rapid and mass fabrication of cell patterns.High-precision three-dimensional(3D)printing was used to manufacture a mold with a resolution of 2µm,and the gelatin-based hydrogel was cured by thermal–photo-crosslinking so that the low-concentration and low-substitutionrate hydrogel could be demolded successfully.We found that pre-cooling before illumination made gelatin-based hydrogels resilient due to the partial regain of triple-helix structures.With this method,arbitrarily customized hydrogel patterns with a feature size of 6–80µm can be fabricated stably and at low cost.When cardiomyocytes were seeded on ultra-soft hydrogels with parallel groove structures,a consistent and spontaneous beating with 216 beats per minute(BPM)could be observed,approaching the natural beating rate of rat hearts(300 BPM).Overall,this work provides a general scheme for manufacturing cell patterns which has great potential for cell ethology and tissue repair.

PERIODIC STREAM LINES IN THE THREE-DIMENSIONAL SQUARE CELL PATTERN

By using the theory of the generalized perturbed Hamiltonian systems, it is shown that there exist periodic stream lines in the three_dimensional square cell pattern of Rayleigh_Benard convection. The result means that our method enables this three_dimensional flow pattern to be described in an unambiguous manner, and some experimental results of other authors can be explained.

Controlled Cell Patterning on Bioactive Surfaces with Special Wettability

The ability to control cell patterning on artificial substrates with various physicochemical properties is of essence for important implications in cytology and biomedical fields. Despite extensive progress, the ability to control the cell-surface interaction is complicated by the complexity in the physiochemical features of bioactive surfaces. In particular, the manifesta- tion of special wettability rendered by the combination of surface roughness and surface chemistry further enriches the cell-surface interaction. Herein we investigated the cell adhesion behaviors of Circulating Tumor Cells （CTCs） on topog- raphically patterned but chemically homogeneous surfaces. Harnessing the distinctive cell adhesion on surfaces with different topography, we further explored the feasibility of controlled cell patterning using periodic lattices of alternative topographies. We envision that our method provides a designer＇s toolbox to manage the extracellular environment.

Acoustofluidics for cell patterning and tissue engineering

Acoustofluidics has been a promising approach using sound waves to manipulate particles and actuate fluids in biomedical applications.It usually generates acoustic radiation force and acoustic streaming to initiate diffraction,reflection and interference,building up a pressure distribution to facilitate accurate manipulation of micro-or nano-scale particles and fluids.Owing to its remarkable contact-free and biocompatible advantages,acoustoflu-idics has been used in high-throughput cell analysis,size-controllable organoid structures,and functional tissue mimics.We enumerate the basic concepts and the sufficient research of acoustofluidics in precise patterning and tissue engineering in this review,including the design and function of four typical acoustofluidic devices,var-ious forms of cell patterning and 3D tissue engineering.Meanwhile,we outlined current challenges and future directions of acoustofluidics in biomedicine and tissue engineering.

眼斑双锯鱼(Amphiprion ocellaris)发育中体色花纹时序发生的色素细胞变化和控制基因表达的分析Ⅱ.仔稚幼鱼时期

眼斑双锯鱼(Amphiprion ocellaris)属于鲈形目、雀鲷科、双锯鱼属,是热带珊瑚礁观赏鱼类的首选品种,其不同发育时期各种色素细胞的动态变化及其控制基因表达情况有待深入研究。记录了眼斑双锯鱼仔稚幼鱼体色花纹模式建成的发育过程,对比不同发育时期体色变化的特点,筛选出仔稚幼鱼时期体色花纹变化较为明显的9个发育时期,并利用荧光定量PCR检测了眼斑双锯鱼各发育时期的10个体色控制基因的表达情况。结果显示:眼斑双锯鱼的体色发生存在明显的时序性,仔鱼时期鱼体呈现半透明状,黑色素细胞排列在身体两侧,随着生长发育数量逐渐增多;稚鱼时期,体表开始出现红色素细胞和黄色素细胞,身体慢慢变得不透明,9 dph开始出现第一道条纹,虹彩色素细胞数量逐渐增多,10 dph时期观察到第二道条纹出现;幼鱼时期,三道白色条纹完全形成,体表的橙红色和白色条纹被黑色素细胞分隔开来,界线逐渐清晰,长成完整的花纹。结合荧光定量PCR结果分析发现:在仔稚幼鱼阶段,10个体色控制基因在各发育时期均有表达,不同功能分类的基因在不同发育时期的表达变化趋势差异较大,在仔稚幼鱼前期表达量变化较大的基因主要为TYR、Dct、Ednrb、Sox10等与黑色素细胞迁移、分化、合成相关的基因;随着幼鱼不断的生长发育,白色条纹逐条出现,与虹彩色素细胞相关的Fms、Foxd3等基因也开始出现表达量显著上升的趋势。

Honokiol-enhanced cytotoxic T lymphocyte activity against cholangiocarcinoma cells mediated by dendritic cells pulsed with damage-associated molecular patterns

BACKGROUND Cholangiocarcinoma or biliary tract cancer has a high mortality rate resulting from late presentation and ineffective treatment strategy. Since immunotherapy by dendritic cells (DC) may be beneficial for cholangiocarcinoma treatment but their efficacy against cholangiocarcinoma was low. We suggest how such antitumor activity can be increased using cell lysates derived from an honokioltreated cholangiocarcinoma cell line (KKU-213L5). AIM To increase antitumour activity of DCs pulsed with cell lysates derived from honokiol-treated cholangiocarcinoma cell line (KKU-213L5). METHODS The effect of honokiol, a phenolic compound isolated from Magnolia officinalis, on choangiocarcinoma cells was investigated in terms of the cytotoxicity and the expression of damage-associated molecular patterns (DAMPs). DCs were loaded with tumour cell lysates derived from honokiol-treated cholangiocarcinoma cells their efficacy including induction of T lymphocyte proliferation, proinflammatory cytokine production and cytotoxicity effect on target cholangiocarcinoma cells were evaluated. RESULTS Honokiol can effectively activate cholangiocarcinoma apoptosis and increase the release of damage-associated molecular patterns. DCs loaded with cell lysates derived from honokiol-treated tumour cells enhanced priming and stimulated T lymphocyte proliferation and type I cytokine production. T lymphocytes stimulated with DCs pulsed with cell lysates of honokiol-treated tumour cells significantly increased specific killing of human cholangiocarcinoma cells compared to those associated with DCs pulsed with cell lysates of untreated cholangiocarcinoma cells. CONCLUSION The present findings suggested that honokiol was able to enhance the immunogenicity of cholangiocarcinoma cells associated with increased effectiveness of DC-based vaccine formulation. Treatment of tumour cells with honokiol offers a promising approach as an ex vivo DC-based anticancer vaccine.

A comparison of the spontaneous firing patterns between principal cells and fast spiking interneurons from dentate gyrus in waking guinea pigs

Objective To explore the possible mechanisms that cause the dentate gyrus （DG） neurons to play different roles in information coding. Methods In vivo extracellular single unit recording was performed on 22 waking female guinea pigs, which were positioned in a sound-attenuated recording chamber without any muscular relaxants. The spontaneous firing patterns of the DG neurons were detected and compared. Results There were two different electrophysiologi- cal populations in the DG of guinea pigs, principal cells （PCs） and fast spiking interneurons （INs）. Of the PCs, 1.3% discharged regularly, 48.1% irregularly and 50.6% in bursts ; in contrast, of the INs units, 64.1% discharged regularly, 2.6% irregularly and 33.3% in bursts. The spontaneous firing patterns of PCs were significantly different from those of INs （P 〈0.01 ）. In addition, the differences of several interspike interval （ISI） parameters also have been observed： （1） the ISI coefficients of variation of PCs （3.39 ± 3.56） were significantly higher than those of INs （1.08 ± 0.46） （P 〈0.01） ; （2） the ISI asymmetric indexes of PCs （0. 047±0. 059） were significantly lower than those of INs （0.569±0. 238） （P 〈 0.01 ）. Conclusion In the DG, the spontaneous firing patterns of PCs were significantly different from those of INs. The former were prone to fire in bursts, the latter were prone to fire regularly. The different roles in information coding between PCs and INs might be caused by their different firing patterns.

Comparison of phase unwrapping algorithms for living cell's interference pattern

A multiphase microscopic interference system is designed to measure the height of cell which is important to the research of collective cell migration in physiology and medicine. This sys- tem can quantitatively measure cell height across a living monolayer without knowing the refractive index of cells. For the interference pattern, because the phases are all wrapped between - π to π, it is necessary to get the real phase through phase unwrapping,a method to restore the wrapped phase data of the object by using numerical calculations. Three representative algorithms are selected to unwrap the interference pattern of ceils： branch-cut method, quality-guided method and network method. Although each of them can restore the phase, their performances are obviously different. We compare these methods and find that branch-cut method needs the smallest execution time and can obtain good unwrapped patterns when noises are not serious.

Demonstration of reversible retinal ganglion cell dysfunction in inflammatory optic neuropathies utilizing pattern electroretinography

Dear Editor,I am Dr.Austin Bach from Larkin Community Hospital in South Miami,Florida,USA.I am writing to you to present three cases of inflammatory optic neuritis that was followed to resolution using pattern electroretinography（PERG）.

Comparisons of ganglion cell-inner plexiform layer loss patterns and its diagnostic performance between normal tension glaucoma and primary open angle glaucoma: a detailed, severity-based study

AIM: To evaluate the patterns of macular ganglion cell-inner plexiform layer(GCIPL) loss in normal tension glaucoma(NTG) and primary open angle glaucoma(POAG) in a detailed, disease severity-matched way;and to assess the diagnostic capabilities of GCIPL thickness parameters in discriminating NTG or POAG from normal subjects.METHODS: A total of 157 eyes of 157 subjects, including 57 normal eyes, 51 eyes with POAG and 49 eyes with NTG were enrolled and strictly matched in age, refraction, and disease severity between POAG and NTG groups. The average, minimum, superotemporal, superior, superonasal, inferonasal, inferior, and inferotemporal GCIPL thickness, and the average, superior, temporal, inferior, and nasal retinal nerve fiber layer(RNFL) thickness were obtained by Cirrus optical coherence tomography(OCT). The diagnostic capabilities of OCT parameters were assessed by area under receiver operating characteristic(AUROC) curves. RESULTS: Among all the OCT thickness parameters, no statistical significant difference between NTG group and POAG group was found(all P>0.05). In discriminating NTG or POAG from normal subjects, the average and inferior RNFL thickness, and the minimum GCIPL thickness had better diagnostic capabilities. There was no significant difference in AUROC curve between the best GCIPL thickness parameter(minimum GCIPL) and the best RNFL thickness parameter in discriminating NTG(inferior RNFL;P=0.076) and indiscriminating POAG(average RNFL;P=0.913) from normal eyes.CONCLUSION: Localized GCIPL loss, especially in the inferior and inferotemporal sectors, is more common in NTG than in POAG. Among all the GCIPL thickness parameters, the minimum GCIPL thickness has the best diagnostic performance in differentiating NTG or POAG from normal subjects, which is comparable to that of the average and inferior RNFL thickness.

Target morphology and cell memory:a model of regenerative pattern formation

Despite the growing body of work on molecular components required for regenerative repair,we still lack a deep understanding of the ability of some animal species to regenerate their appropriate complex anatomical structure following damage.A key question is how regenerating systems know when to stop growth and remodeling-what mechanisms implement recognition of correct morphology that signals a stop condition？In this work,we review two conceptual models of pattern regeneration that implement a kind of pattern memory.In the first one,all cells communicate with each other and keep the value of the total signal received from the other cells.If a part of the pattern is amputated,the signal distribution changes.The difference fromthe original signal distribution stimulates cell proliferation and leads to pattern regeneration,in effect implementing an error minimization process that uses signaling memory to achieve pattern correction.In the second model,we consider a more complex pattern organization with different cell types.Each tissue contains a central（coordinator）cell that controls the tissue and communicates with the other central cells.Each of them keeps memory about the signals received from other central cells.The values of these signals depend on the mutual cell location,and the memory allows regeneration of the structure when it is modified.The purpose of these models is to suggest possible mechanisms of pattern regeneration operating on the basis of cell memory which are compatible with diverse molecular implementation mechanisms within specific organisms.

Clinicopathological Pattern of Basal Cell Carcinoma among Sudanese Patients

Background: Basal cell carcinoma (BCC) is a frequently diagnosed skin cancer with variable histopathological types. BCC was not widely studied in Sudan as it is in the Caucasian population. Objectives: To appraise the clinical and histopathological aspects of BCC of the skin in Sudan. Materials and methods: A retrospective descriptive analysis of 84 histologically diagnosed BCC specimens seen at three hospitals in four-year duration were reviewed and classified into histological variants according to the WHO classification 2006. Data were analyzed using Statistical Package for the Social Sciences, version 23.0. Results: The mean age (±SD) of the study participants was 56 (±1.75) years, ranging from 20 to 92 years and 63.1% were females (Female to male ratio 1.7:1). The most common incidence was among the age group 51 - 60 years. The face was the primary tumor site in 89.3% with a predilection for the nasal area (31% of those in the face), followed by the trunk (6%). Out of the total, 54.8% were histologically categorized as nodular/solid, while infiltrative accounts for 11.9% followed by the superficial type (8.3%). Surgical margins were involved in 34.5% of cases and peri-neural invasion was seen in 3.6% of cases, mostly were of the infiltrative variant. Conclusion: BCC in Sudan is commonly present in the head as solid nodular histopathological variant which is correlated with worldwide distribution but has slightly younger age and female predominance;thus further studies are needed to assess risk factors in Sudanese patients and improve approaches for earlier diagnosis and better management.

Treatment Patterns and Clinical Characteristics of Patients with Advanced Basal Cell Carcinoma in the Community Oncology Setting

Advanced basal cell carcinoma (aBCC) includes metastatic and locally advanced BCC that is inoperable (or with surgery contraindicated). We describe patient characteristics and treatment history for aBCC cases from community oncology. Nine cases of aBCC were found within the ACORN Data Warehouse, a community oncology database of >180,000 cancer patients. Data were summarized descriptively. Three illustrative case histories are presented. Patients were predominantly Caucasian (8/9), male (6/9), and over 60 (6/9). Four had metastatic disease;five had aBCC without metastasis. Five had a history of treatment for early stage BCC, including surgery (5/5), radiation (1/5), and none had chemotherapy. Those with history of early stage BCC had periods of apparent lack of follow-up and treatment. One had chemotherapy for aBCC (platinum based with radiation) and eight had radiation without chemotherapy. Patients had multiple comorbid serious medical conditions. Six were deceased, but only one was documented to have aBCC as cause of death. Advanced BCC is rare in community oncology settings. There appear to be gaps in the care and follow-up of patients with initial early stage BCC. More data and larger samples are needed from multi-specialty databases such as dermatology and head and neck surgery.

Preparation of patterned boron nanowire films with different widths of unit-cell and their field emission properties

Large-area patterned films of boron nanowires（BNWs） are fabricated at various densities by chemical vapor deposition（CVD）. Different widths of unit-cell of Mo masks are used as templates. The widths of unit-cell of Mo masks are100 μm, 150 μm, and 200 μm, respectively. The distance between unit cells is 50 μm. The BNWs have an average diameter of about 20 nm and lengths of 10 μm–20 μm. High-resolution transmission electron microscopy analysis shows that each nanowire has a β-tetragonal structure with good crystallization. Field emission measurements of the BNW films show that their turn-on electric fields decrease with width of unit-cell increasing.

¹⁸FDG-PET/CT Is a Useful Tool in Staging Procedure before Chemo-Radiotherapy in Patients with Limited Disease Small-Cell Lung Cancer. Pattern of Failure and Survival Is Analyzed

Background: The purpose of this study was to evaluate the use of 18FDG-PET/CT in staging procedure, the pattern of failure and survival in patients with small-cell lung cancer limited disease (LD-SCLC) undergoing chemo-radiotherapy. Methods: A total of 79 LD-SCLC patients were treated with a combination of chemotherapy and chest radiotherapy. Radiotherapy of the tumour and the pathological lymph nodes was performed either as 45 Gy twice-daily or 46 - 50 Gy once-daily. 18Fluro-2-deoxy-D-glucose (18FDG)-PET/CT was performed in 35 patients as part of the staging procedure. Results: With a median follow-up time of 17 months 6% developed isolated loco-regional failures while 57% developed distant metastases. No isolated regional failures were seen. Median overall survival was 22 months. Patients staged with a 18FDG-PET/CT had a significantly lower incidence of distant failures and a significantly improved overall survival compared with patients only staged with a CT scan (p = 0.03) (median overall survival of 34 versus 17 months, respectively). Conclusion: The pattern of failure showed a high risk of distant metastases but a low incidence of isolated loco-regional failures. Patients staged with an 18FDG-PET/CT had a significantly lower incidence of distant failures and better overall survival, indicating that 18FDG-PET could be beneficial in patients with LD-SCLC before deciding on treatment regimen.

坏死性凋亡分子机制及与牙周炎的相关性

背景:近年来,随着细胞死亡研究的不断深入,坏死性凋亡逐渐成为学术界研究的热点和难点,其多种信号通路及蛋白在牙周炎的发生发展中起到不可忽视的作用,人们试图通过阻止细胞坏死性凋亡的发生,从而延缓牙周组织炎症的进程。目的:就坏死性凋亡的分子机制及其与牙周炎的相关性进行综述,期望为牙周炎的预防、诊断、治疗及预后提供新思路、新方向。方法:第一作者于2023年10月应用计算机检索PubMed、中国知网等数据库建库到2024年4月发表的相关文献,以“坏死性凋亡,细胞程序性死亡,牙周炎,牙周,免疫,炎症,受体相互作用蛋白激酶1,受体相互作用蛋白激酶3,混合系列蛋白激酶样结构域”为中文检索词;“necroptosis,programmed cell death,periodontitis,periodontal,immunity,inflammation,RIP1,RIP3,MLKL”为英文检索词,阅读每篇文献的文题、摘要、引言进行初步筛选,最终纳入56篇文献进行总结分析。结果与结论:①牙周炎的主要发病机制为牙周致病菌刺激机体,导致牙周微环境发生改变,打破原有免疫平衡并释放各种炎症因子,引发炎症反应造成牙周组织破坏,坏死性凋亡可以调控牙周组织免疫炎症反应,从而影响牙周炎的发生发展进程;②坏死性凋亡的发生与多种蛋白、信号通路及信号分子有关,已有动物实验证实了磷酸化混合系列蛋白激酶样结构域(pMLKL)的表达量与炎症程度有关,且在患有牙周炎小鼠的牙周组织中,RIP3和pMLKL高表达,通过阻断RIP3/MLKL通路,有利于减少牙周组织炎症、控制牙周炎的进展;③探究pMLKL是否可作为牙周炎的诊断指标,在牙周炎的预防、诊断及治疗上有很大价值。

CARP-1(Cell Division Cycle and Apoptosis Regulator Protein 1)的生物功能和表达模式探究

本文对CARP-1生物功能和表达模式进行了研究,结果表明,作为一个关键的细胞内复合物,传感激活细胞的增殖或凋亡信号通路,在经典Wnt通路中,CARP-1与β-catenin功能共激活,协助β-catenin在Wnt目标基因作用中的转录激活,涉及到一些蛋白信号的扩散和转移;参与caspase泛素化蛋白酶途径,与APC/C复合,在CFM-4的阻碍作用下,阻滞G2/M细胞周期;与P53、P160复合,刺激靶细胞激素代谢,调控细胞周期,通过增强CDK1和P21的水平来调节细胞凋亡。

Role of Hox genes in stem cell differentiation

Hox genes are an evolutionary highly conserved gene family. They determine the anterior-posterior body axis in bilateral organisms and influence the developmental fate of cells. Embryonic stem cells are usually devoidof any Hox gene expression, but these transcription factors are activated in varying spatial and temporal patterns defining the development of various body regions. In the adult body, Hox genes are among others responsible for driving the differentiation of tissue stem cells towards their respective lineages in order to repair and maintain the correct function of tissues and organs. Due to their involvement in the embryonic and adult body, they have been suggested to be useable for improving stem cell differentiations in vitro and in vivo. In many studies Hox genes have been found as driving factors in stem cell differentiation towards adipogenesis, in lineages involved in bone and joint formation, mainly chondrogenesis and osteogenesis, in cardiovascular lineages including endothelial and smooth muscle cell differentiations, and in neurogenesis. As life expectancy is rising, the demand for tissue reconstruction continues to increase. Stem cells have become an increasingly popular choice for creating therapies in regenerative medicine due to their self-renewal and differentiation potential. Especially mesenchymal stem cells are used more and more frequently due to their easy handling and accessibility, combined with a low tumorgenicity and little ethical concerns. This review therefore intends to summarize to date known correlations between natural Hox gene expression patterns in body tissues and during the differentiation of various stem cells towards their respective lineages with a major focus on mesenchymal stem cell differentiations. This overview shall help to understand the complex interactions of Hox genes and differentiation processes all over the body as well as in vitro for further improvement of stem cell treatments in future regenerative medicine approaches.

Numerical simulation of neuronal spike patterns in a retinal network model

This study utilized a neuronal compartment model and NEURON software to study the effects of external light stimulation on retinal photoreceptors and spike patterns of neurons in a retinal network Following light stimulation of different shapes and sizes, changes in the spike features of ganglion cells indicated that different shapes of light stimulation elicited different retinal responses. By manipulating the shape of light stimulation, we investigated the effects of the large number of electrical synapses existing between retinal neurons. Model simulation and analysis suggested that interplexiform cells play an important role in visual signal information processing in the retina, and the findings indicated that our constructed retinal network model was reliable and feasible. In addition, the simulation results demonstrated that ganglion cells exhibited a variety of spike patterns under different light stimulation sizes and different stimulation shapes, which reflect the functions of the retina in signal transmission and processing.

Mathematical simulation of gas induced bath flow in drained aluminum reduction cell

A mathematical model describing the bubble driven bath flow in a drained cell with a center sump was presented, which spanned the fluid around half an anode and was developed to simulate the flow fields. The calculated results show reasonable agreement with the experiment. Then the model was developed to a full cell model, and bath flow pattern in the whole cell was predicted and analyzed. The flow pattern variation with the changes of the ACD, anode slope, anode immersion depth and current density, especially the fluid secondary recirculation, was modeled. According to the results, side channel or slots feeding technique was recommended in such a drained cell.