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1.
Dig Dis Sci ; 62(11): 3069-3076, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28664410

RESUMEN

BACKGROUND: Eradication therapies for Helicobacter pylori infection are advancing as new acid inhibitory reagents approved. The aim of this study was to assess the efficacy and safety of vonoprazan-based triple treatment. MATERIALS AND METHODS: Triple therapy with vonoprazan and two antibiotics (amoxicillin and clarithromycin or metronidazole) received focus in this analysis. We performed a multicenter retrospective study of patients who received vonoprazan-based eradication therapy between February 2015 and February 2016 and conducted a review of the literature. RESULTS: The eradication rate among the 799 patients in our multicenter study was 94.4% (95% confidence interval [CI] 92.6-96.2%) in the per-protocol analysis for first-line treatment (with vonoprazan 20 mg, amoxicillin 750 mg, and clarithromycin 200 or 400 mg, twice a day for 7 days) and 97.1% (95% CI 93.0-101.1%) for second-line treatment (with vonoprazan 20 mg, amoxicillin 750 mg, and metronidazole 250 mg, twice a day for 7 days). The overall incidence of adverse events was 4.4% in an intention-to-treat analysis with no patients hospitalized. In a literature review, six reports, in which 1380 patients received vonoprazan-based first-line eradication therapy, were included and were all reported by Japanese researchers. The eradication success rates in per-protocol analysis were between 85 and 93%, which was roughly the same among the studies. CONCLUSIONS: Vonoprazan-based triple therapy was effective and safe for Helicobacter pylori eradication in real-world experience, confirmed by a multicenter study and a review of the pertinent literature.


Asunto(s)
Amoxicilina/administración & dosificación , Claritromicina/administración & dosificación , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/efectos de los fármacos , Metronidazol/administración & dosificación , Inhibidores de la Bomba de Protones/administración & dosificación , Pirroles/administración & dosificación , Sulfonamidas/administración & dosificación , Anciano , Amoxicilina/efectos adversos , Claritromicina/efectos adversos , Quimioterapia Combinada , Femenino , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/microbiología , Helicobacter pylori/aislamiento & purificación , Humanos , Japón , Masculino , Metronidazol/efectos adversos , Persona de Mediana Edad , Inhibidores de la Bomba de Protones/efectos adversos , Pirroles/efectos adversos , Inducción de Remisión , Estudios Retrospectivos , Sulfonamidas/efectos adversos , Factores de Tiempo , Resultado del Tratamiento
2.
Nihon Shokakibyo Gakkai Zasshi ; 113(7): 1208-15, 2016 07.
Artículo en Japonés | MEDLINE | ID: mdl-27383104

RESUMEN

Upper gastrointestinal (GI) lesions are frequently reported in Crohn's disease, in which the entire GI tract is affected. In these cases, erosive fissures regularly transversing folds that are longitudinally aligned along the lesser curvature of the gastric body and cardia are described as having a "bamboo joint-like appearance". We designed a blinded experiment in which upper GI imaging without a final diagnosis was checked by three observers to determine the usefulness of the bamboo joint-like appearance in the diagnosis of Crohn's disease. For the three observers, sensitivities of appearance were 30.5%, 56.9%, and 51.4%, while specificities were 99.6%, 98.5%, and 99.3%. Thus, the bamboo joint-like appearance was not useful for the identification of Crohn's disease patients. Nevertheless, patients exhibiting the bamboo joint-like appearance in upper GI imaging should undergo further examination due to the high probability of Crohn's disease.


Asunto(s)
Enfermedad de Crohn/diagnóstico , Adulto , Endoscopía del Sistema Digestivo , Femenino , Humanos , Masculino
3.
Ann Med Surg (Lond) ; 86(7): 4227-4230, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38989225

RESUMEN

Introduction: Gastric cancer has been reported to occur with mild to moderate mucosal atrophy, particularly after the eradication of Helicobacter pylori (HP) more than 10 years previously. However, no conclusion has been reached on how many years of esophagogastroduodenoscopy should be performed after HP eradication. Presentation of case: This was a case of gastric carcinoma of the fundic gland type (GCFGT) 32 years after the eradication of HP, which is the longest posteradication period reported. A 62-year-old male patient was diagnosed with GCFGT after HP eradication and regular esophagogastroduodenoscopy, which revealed a white raised lesion on the anterior wall of the upper part of the body. Endoscopic submucosal dissection was performed for GCFGT, and the vertical and horizontal margins were negative. Clinical discussion: In this case, HP was eradicated in 1990, and GCFGT developed 32 years later. To the best of our knowledge, this is the longest case in which gastric cancer appeared after HP eradication. HP eradication therapy for a duodenal ulcer was first reported in 1990, supporting that this is the longest case. Conclusions: This is the first case of gastric cancer more than 20 years after the eradication of HP. The endoscopic findings of this case are typical of GCFGT and may be useful when encountering such cases in the future. Therefore, the risk of gastric cancer should be considered for an extended period even after the eradication of HP, and regular esophagogastroduodenoscopy is recommended even after the eradication of HP.

4.
Anal Chem ; 85(3): 1683-8, 2013 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-23249269

RESUMEN

Medicines are distributed to the whole body and excreted over time. A micromodel of the circulation-excretion system was developed to mimic these processes. This system comprised a dialysis part, a microperistaltic pump, and a target tissue. This microcirculation system was created on a microchip composed of a glass slide and polydimethylsiloxane sheets with microchannels fabricated by photolithography. A dialysis membrane was settled between two channels to form the dialysis part, and a pneumatic peristaltic pump was used to make the solution flow. The excretion and half-life of solute substances absorbed to albumin were changed according to their affinity to the protein. MCF-7 human breast cancer cells were cultured as target cells for drug samples, and the activities of anticancer agents were assayed using our system. Our data demonstrated that the anticancer activity of docetaxel or thio-TEPA could be assayed on the microcirculation-excretion chip. This system may allow for reduced consumption of cells and reagents compared to those required for conventional in vitro bioassay systems.


Asunto(s)
Antineoplásicos/metabolismo , Electroforesis por Microchip/métodos , Microcirculación , Antineoplásicos/farmacología , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Diálisis/instrumentación , Diálisis/métodos , Electroforesis por Microchip/instrumentación , Humanos , Células MCF-7
5.
Anal Biochem ; 437(1): 43-5, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23467098

RESUMEN

Padlock rolling circle amplification (RCA) is a powerful analytical method for ultrasensitive DNA detection. Although there are some advantages to bead-based RCA, a detailed study of the relationship between the bead material and the efficiency of bead-based RCA has not been reported. Here, we compared the reaction efficiencies of bead-based RCA performed on two types of bead material: agarose and polystyrene. Agarose was a more suitable material for on-bead RCA. The calibration curve showed linearity between 0.05 and 1 nM, and the limit of detection was 9 pM (9 amol) for Salmonella DNA determination.


Asunto(s)
ADN Bacteriano/análisis , Microesferas , Técnicas de Amplificación de Ácido Nucleico/métodos , Secuencia de Bases , ADN Bacteriano/genética , Hibridación de Ácido Nucleico , Salmonella/genética
6.
J Biochem ; 174(3): 273-278, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37141918

RESUMEN

Cryopreservation of mammalian cells is an important technology; however, freezing damage due to osmotic pressure differences and ice crystal formation is inevitable. In addition, cryopreserved cells cannot be used immediately after thawing in many cases. Therefore, in this study, we developed a method for supercooling and preserving adherent cells using a precision temperature-controlled CO2 incubator. The effects of the cooling rate from 37 to -4°C, the warming rate from -4 to 37°C and a preservation solution on cell viability after storage were examined. Human hepatocarcinoma-derived cell line HepG2 cells, preserved with HypoThermosol FRS at -4°C with a cooling rate of -0.028°C/min (24 h from 37°C to -4°C) and warming to 37°C at a rate of +1.0°C/min (40 min from -4 to 37°C), displayed high cell viability after 14 days of preservation. The superiority of supercooling preservation at -4°C was demonstrated by comparing the obtained results with that of refrigerated preservation at +4°C. Cells preserved for 14 days under optimal conditions showed no cell shape abnormalities and may be used for experiments immediately after thawing. The optimized supercooling preservation method determined in this study is suitable for the temporary preservation of adherent cultured cells.


Asunto(s)
Frío , Criopreservación , Humanos , Supervivencia Celular , Células Cultivadas , Criopreservación/métodos , Congelación , Temperatura
7.
Ann Med Surg (Lond) ; 85(2): 214-218, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36845819

RESUMEN

The initial appearance of malignant melanoma localized in the stomach has never been reported previously. We encountered a patient with gastric melanoma in the stomach, which was histologically confirmed to be confined to the mucosa. Case Presentation: The patient, when in her 40s, had undergone surgery for malignant melanoma of the left heel. However, there were no detailed records of pathological findings. The patient had a 4-mm black elevated lesion in her stomach observed on esophagogastroduodenoscopy after the eradication of Helicobacter pylori. A year later, esophagogastroduodenoscopy showed that the lesion had increased to 8 mm. A biopsy was performed, but no malignancy was found; the patient continued to be followed up. Esophagogastroduodenoscopy performed at the 2-year follow-up revealed that the melanotic lesion had increased to 15 mm, and biopsy was performed and revealed a malignant melanoma. Clinical Discussion: Endoscopic submucosal dissection was performed for gastric malignant melanoma. The margin of the resected malignant melanoma was negative; vascular and lymphatic invasions were not observed, and the lesion was confined to the mucosa. Conclusion: We suggest that even if the first biopsy of a melanotic lesion shows no evidence of malignancy, the lesion should be closely monitored. This is the first reported case of endoscopic submucosal dissection of localized gastric malignant melanoma confined to the mucosa.

8.
Ann Med Surg (Lond) ; 85(7): 3269-3272, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37427181

RESUMEN

Diagnosing the invasion depth of ulcerated early gastric cancer is usually inaccurate, especially for endoscopists in primary care clinics who are often not experts in this area. In reality, many patients with open ulcers who can be treated with endoscopic submucosal dissection (ESD) are referred for surgery. Materials and methods: Twelve patients with ulcerated early gastric cancer who were treated with proton pump inhibitors, including vonoprazan, and underwent ESD were included in the study. Conventional endoscopic and narrow-band images were evaluated by five board-certified endoscopists (two physicians: A, B, and three gastrointestinal surgeons: C, D, and E). They assessed the invasion depth, and the results were compared with the pathologic diagnosis. Results: The accuracy of the invasion depth diagnosis was 38.3%. According to the pretreatment diagnosis of invasion depth, gastrectomy was recommended for 41.7% (5/12) of the cases. However, histological examination revealed that additional gastrectomy was required in only one case (8.3%). Thus, in four out of five patients unnecessary gastrectomy could be avoided. Post-ESD mild melena occurred in only one case, and there was no case of perforation. Conclusion: Antiacid treatment contributed to avoid unnecessary gastrectomy in four out of five patients for whom gastrectomy was indicated based on an inaccurate pretreatment diagnosis of the invasion depth.

9.
Ann Med Surg (Lond) ; 73: 103141, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34976381

RESUMEN

Colonic diverticular bleeding is the most common type of gastrointestinal bleeding. We report a case of an 82-year-old man with a chief complaint of melena. Enhanced computed tomography showed multiple diverticula, and water-assisted colonoscopy could not help identify the diverticulum responsible for bleeding. We injected VISCOCLEAR, a novel gel formulation, into the digestive tract endoscopically and successfully localized the bleeding point. Moreover, the use of VISCOCLEAR secured a clear visual field with reduced glare, as seen in the digital endoscopic image. Subsequently, we performed hemostatic clipping. The course after the endoscopic treatment was unremarkable. In this case, we could identify the exposed bleeding vessels in the diverticulum using VISCOCLEAR and perform hemostatic clipping. We intend to evaluate the effectiveness of VISCOCLEAR further by analyzing a series of cases.

10.
Ann Med Surg (Lond) ; 82: 104743, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36268348

RESUMEN

Gel immersion endoscopy was developed by Yano for the treatment of bleeding. In this case, we performed gel immersion endoscopic mucosal resection to treat a bleeding gastric cancer. An 80-year-old man, with chronic renal failure and on aspirin treatment for ischemic heart disease, underwent endoscopic treatment for multiple early gastric cancers on the anterior and posterior walls of the pyloric ring. An endoscopic submucosal dissection was performed for gastric cancer on the anterior wall; however, the removal of the cancer on the posterior wall was complicated by tumor prolapse and bleeding. Gel formulation (VISCOCLEAR® Otsuka Pharmaceutical Factory, Inc., Tokushima, Japan) was used to immerse the bleeding tumor and subsequently facilitate the endoscopic mucosal resection. Various factors, such as the use of antithrombotic medication and underlying renal disease, can increase the risk of bleeding during endoscopic gastric cancer resection. If bleeding persists, the resection margin becomes obscured. Gel formulations, such as VISCOCLEAR®, can be applied to control bleeding and improve visibility. In this case, gel immersion was useful for endoscopic mucosal resection of the bleeding tumor. The use of gel immersion endoscopic resection should be considered for the treatment of early gastric cancer, however further cases should be evaluated.

11.
Appl Environ Microbiol ; 77(21): 7551-9, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21908636

RESUMEN

Responses to NaCl stress were investigated in phototrophically grown Alphaproteobacterium Rhodobacter sphaeroides by transcriptome profiling, mutational analysis, and measurements of compatible solutes and membrane phospholipids. After exposure to salt stress, genes encoding two putative glycine betaine uptake systems, proVWX and betS, were highly upregulated. Mutational analysis revealed that BetS, not ProVWX, was the primary transporter of this compatible solute. Upon the addition of salt, exogenous glycine betaine was taken up rapidly, and maximal intracellular levels were reached within minutes. In contrast, synthesis of another important compatible solute in R. sphaeroides, trehalose, increased slowly following salt stress, reaching maximal levels only after several hours. This accumulation pattern was consistent with the more gradual increase in salt-induced transcription of the trehalose biosynthesis operon otsBA. Several genes encoding putative transcription factors were highly induced by salt stress. Multiple copies of one of these factors, crpO (RSP1275), whose product is a member of the cyclic AMP receptor protein/fumarate and nitrate reduction regulator (CRP/FNR) family, improved NaCl tolerance. When crpO was provided in multicopy, expression of genes for synthesis or transport of compatible solutes was unaltered, but the membrane phospholipid composition became biased toward that found in salt-stressed cells. Collectively, this study characterized transcriptional responses to salt stress, correlated changes in transcription with compatible solute accumulation rates, identified the main glycine betaine transporter and trehalose synthase, characterized salt-induced changes in phospholipid composition, and uncovered a transcription factor associated with changes in phospholipids. These findings set the stage for deciphering the salt stress-responsive regulatory network in R. sphaeroides.


Asunto(s)
Lípidos de la Membrana/metabolismo , Metaboloma , Presión Osmótica , Rhodobacter sphaeroides/efectos de los fármacos , Cloruro de Sodio/metabolismo , Estrés Fisiológico , Transcriptoma , Betaína/metabolismo , Análisis Mutacional de ADN , Rhodobacter sphaeroides/fisiología , Transducción de Señal , Cloruro de Sodio/toxicidad , Factores de Tiempo , Trehalosa/metabolismo
12.
Asia Pac Allergy ; 11(4): e44, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34786374

RESUMEN

Eosinophilic esophagitis (EoE) is a chronic inflammatory disease associated with eosinophilic infiltration of the esophageal mucosa mostly due to exposure to allergens. However, the causes and pathogenesis of EoE are not fully understood. We encountered a case of EoE that was triggered by sublingual immunotherapy (SLIT) for cedar pollen allergy. A 40-year-old man who was treated with Japanese cedar pollen tablet SLIT for cedar pollen allergy developed heartburn 3 weeks after the initiation of the treatment. He took vonoprazan for the heartburn, but the heartburn did not improve. Then, esophagogastroduodenoscopy was performed; it revealed longitudinal furrows and white spots on the esophageal mucosa, decreased vascular permeability, and erosions. Consequently, the patient was diagnosed with EoE. Heartburn and chest discomfort disappeared 1 week after the discontinuation of Japanese cedar pollen tablet SLIT, and the patient tested positive for drug allergy to Japanese cedar pollen tablet SLIT. In this study, we found that if heartburn persists during SLIT for cedar pollen allergy, and does not improve on administration of vonoprazan or proton pump inhibitors, EoE should be suspected. In addition, the occurrence of EoE due to drug allergy is indicated.

13.
Lab Chip ; 10(10): 1262-6, 2010 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-20445878

RESUMEN

The sensitive detection and quantification of DNA targets in the food industry and in environmental and clinical settings are issues of utmost importance in ensuring contamination-free food, monitoring the environment, and battling disease. Selective probes coupled with powerful amplification techniques are therefore of major interest. In this study, we set out to create an integrated microchemical chip that benefits from microfluidic chip technology in terms of sensitivity and a strong detection methodology provided jointly by padlock probes and rolling circle amplification (RCA). Here, we have integrated padlock probes and RCA into a microchip. The chip uses solid phase capture in a microchannel to enable washing cycles and decrease analytical area, and employs on-bead RCA for single-molecule amplification and detection. We investigated the effects of reagent concentration and amount of padlock probes, and demonstrated the feasibility of detecting Salmonella.


Asunto(s)
ADN/análisis , ADN/genética , Procedimientos Analíticos en Microchip/métodos , Microesferas , Técnicas de Amplificación de Ácido Nucleico/métodos , Secuencia de Bases , ADN Bacteriano/análisis , ADN Bacteriano/genética , Miniaturización , Técnicas de Amplificación de Ácido Nucleico/instrumentación , Salmonella/genética , Salmonella/aislamiento & purificación , Factores de Tiempo
14.
Anal Chem ; 82(24): 9983-8, 2010 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-21090751

RESUMEN

Oral medicines and food constituents are absorbed in the intestine and metabolized in the liver, after which they exhibit their activity toward a target tissue. Micromodels of human tissues were developed to mimic these processes and bioactivities. By integrating the micromodels, we realized a micro total bioassay system for oral substances; this system comprised a microintestine, microliver, and the target components. The microchip was composed of a slide glass and polydimethylsiloxane (PDMS) sheets with microchannels fabricated by photolithography. Caco-2 cells were cultured in the intestine component, and HepG2 cells, in the liver component. The human breast carcinoma MCF-7 cells were cultured in the target component, and the activities of anticancer agents and estrogen-like substances were successfully assayed. By using this system, the overall properties of the ingested cyclophosphamide, epirubicin, 17-ß estradiol, and soy isoflavone, i.e., their intestinal absorption, hepatic metabolism, and bioactivity toward target cells, could be assayed with operative ease. Further, the assay time and cell consumption were reduced compared to those in conventional in vitro bioassay systems.


Asunto(s)
Absorción Intestinal , Hígado/metabolismo , Procedimientos Analíticos en Microchip/métodos , Modelos Biológicos , Antineoplásicos/farmacología , Línea Celular Tumoral , Ciclofosfamida/farmacología , Epirrubicina/farmacología , Estradiol/farmacología , Humanos , Isoflavonas/farmacología , Dispositivos Laboratorio en un Chip
15.
Opt Express ; 18(3): 2522-7, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-20174080

RESUMEN

We generated sub-kilowatt peak-power and 6-ps duration 390-nm optical pulses via the fourth harmonic generation of amplified optical output from a gain-switched 1.55-microm laser diode. We obtained a power-conversion-efficiency of 12% from 1.55-microm to 390-nm light, and subsequently applied the ultraviolet pulses to time-resolved spectroscopy of blue-violet luminescent materials, including a Coumarine dye solution and nitride semiconductor materials using single-photon and two-photon excitation schemes.

16.
Biosci Biotechnol Biochem ; 74(3): 569-72, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20208350

RESUMEN

We developed a large cell culture surface with a nanostripe structure by paving polydimethylsiloxane (PDMS) replicas of a glass mold. The stripe structure has a height of 180 nm and top width of 500 nm with 400-nm intervals between stripes. Human stomach cancer SH-10-TC cells cultured on the surface changed their morphology to elongated shapes parallel to the nanostripes. In addition, cell motility parallel to the stripes was greatly enhanced. These findings strongly suggest that the nanostripe structure affected the cell physiology.


Asunto(s)
Técnicas de Cultivo de Célula , Movimiento Celular , Dimetilpolisiloxanos/química , Nanoestructuras , Adhesión Celular , Dimetilpolisiloxanos/síntesis química , Vidrio , Humanos , Células Tumorales Cultivadas
17.
Case Rep Gastroenterol ; 14(3): 561-569, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33250698

RESUMEN

Cronkhite-Canada syndrome (CCS) is a rare disease characterized by diffuse gastrointestinal polyposis with chronic diarrhea and ectodermal change, but its etiology is unknown. We present a case at the age of 26 years complaining of epigastralgia and weight loss. Endoscopic examination revealed extensive diffuse polypoid lesions of the stomach and the terminal ileum, all of which showed hyperplastic polyps pathologically. There were no polypoid lesions in his colon. He has no family history of diffuse gastrointestinal polyposis. Diffuse gastrointestinal hyperplastic polyposis without any hereditary association led us to suspect this case as CCS although he did not show chronic diarrhea and any ectodermal symptoms such as onychodystrophy, alopecia, and hyperpigmentation. After initiation of a corticosteroid therapy, his epigastralgia disappeared and he gained appetite and weight, accompanied by normalization of serum albumin levels. Endoscopic examination 1 year after initiation of corticosteroid therapy revealed a decrease in the number of gastric polyposis and those inflammations. This rare young case may suggest that early therapeutic intervention with corticosteroids could improve the prognosis of CCS, preventing not only malnutrition but also appearance of several ectodermal symptoms.

18.
Ann Med Surg (Lond) ; 60: 27-30, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33101669

RESUMEN

BACKGROUND: Vonoprazan has been more widely used for artificial ulcers after endoscopic submucosal dissection (ESD) for early gastric cancer; however, no reports have examined intragastric pH during ESD. The present study aimed to measure gastric pH at the time of ESD and the clinical course afterwards for patients treated with vonoprazan the night before undergoing ESD. MATERIALS AND METHODS: We examined medication status regarding gastric acid secretion and antithrombotic drugs, post-ESD bleeding as a perioperative complication, and the timing of upper gastrointestinal endoscopy after ESD and ulcer healing in 156 patients who underwent gastric ESD at our hospital from January 2014 to December 2019. The gastric pH was measured at the time of ESD after administration of 20 mg vonoprazan on the night before gastric ESD. RESULTS: There were 14 cases of post-ESD bleeding in patients treated with proton-pump inhibitors (PPIs), including oozing during second-look endoscopy compared to only 1 case of bleeding with vonoprazan administration (p < 0.05). Vonoprazan was also associated with better post-ESD ulcer healing than PPIs. Gastric pH during ESD after vonoprazan administration on the night before gastric ESD was ≥6.96 in all 11 patients. CONCLUSION: Post-ESD bleeding was reduced, and ulcer healing was improved in patients treated with vonoprazan the night before their procedure. Our results suggest high gastric pH during ESD due to vonoprazan administration may be beneficial for hemostasis and ulcer healing following ESD.

19.
Micromachines (Basel) ; 11(1)2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31906208

RESUMEN

A cell culture on a scaffold has the advantages of functionality and easy handling, because the geometry of the cellular tissue is controlled by designing the scaffold. To create complex cellular tissue, scaffolds should be complex two-dimensional (2D) and three-dimensional (3D) structures. However, it is difficult to fabricate a scaffold with a 2D and 3D structure because the shape, size, and fabrication processes of a 2D structure in creating a cell layer, and a 3D structure containing cells, are different. In this research, we propose a micropatterning method for porous materials using the difference of the glass transition temperature between exposed and unexposed areas of a thick-photoresist. Since the proposed method does not require a vacuum, high temperature, or high voltage, it can be used for fabricating various structures with a wide range of scales, regardless of the materials used. Additionally, the patterning area can be fabricated accurately by photolithography. To evaluate the proposed method, a membrane integrated scaffold (MIS) with a 2D porous membrane and 3D porous material was fabricated. The MIS had a porous membrane with a pore size of 4 µm or less, which was impermeable to cells, and a porous material which was capable of containing cells. By seeding HUVECs and HeLa cells on each side of the MIS, the cellular tissue was formed with the designed geometry.

20.
Anal Sci ; 35(2): 215-218, 2019 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-30224564

RESUMEN

A liquid-core liquid-cladding optical waveguide based on thermal gradients across laminar flow was built with the laminar flow of water in a stainless capillary tube placed in a heat source. Its characteristics were studied with both experiments and a computational fluid dynamics simulation, firstly showing that it had the nature of a graded index optical fiber.

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