ABSTRACT
BACKGROUND: In laparoscopic right hemicolectomy (RHC) for right-sided colon cancer, accurate recognition of the vascular anatomy is required for appropriate lymph node harvesting and safe operative procedures. We aimed to develop a deep learning model that enables the automatic recognition and visualization of major blood vessels in laparoscopic RHC. MATERIALS AND METHODS: This was a single-institution retrospective feasibility study. Semantic segmentation of three vessel areas, including the superior mesenteric vein (SMV), ileocolic artery (ICA), and ileocolic vein (ICV), was performed using the developed deep learning model. The Dice coefficient, recall, and precision were utilized as evaluation metrics to quantify the model performance after fivefold cross-validation. The model was further qualitatively appraised by 13 surgeons, based on a grading rubric to assess its potential for clinical application. RESULTS: In total, 2624 images were extracted from 104 laparoscopic colectomy for right-sided colon cancer videos, and the pixels corresponding to the SMV, ICA, and ICV were manually annotated and utilized as training data. SMV recognition was the most accurate, with all three evaluation metrics having values above 0.75, whereas the recognition accuracy of ICA and ICV ranged from 0.53 to 0.57 for the three evaluation metrics. Additionally, all 13 surgeons gave acceptable ratings for the possibility of clinical application in rubric-based quantitative evaluations. CONCLUSION: We developed a DL-based vessel segmentation model capable of achieving feasible identification and visualization of major blood vessels in association with RHC. This model may be used by surgeons to accomplish reliable navigation of vessel visualization.
Subject(s)
Colonic Neoplasms , Deep Learning , Laparoscopy , Humans , Colonic Neoplasms/diagnostic imaging , Colonic Neoplasms/surgery , Colonic Neoplasms/blood supply , Retrospective Studies , Laparoscopy/methods , Colectomy/methodsABSTRACT
BACKGROUND: The precise recognition of liver vessels during liver parenchymal dissection is the crucial technique for laparoscopic liver resection (LLR). This retrospective feasibility study aimed to develop artificial intelligence (AI) models to recognize liver vessels in LLR, and to evaluate their accuracy and real-time performance. METHODS: Images from LLR videos were extracted, and the hepatic veins and Glissonean pedicles were labeled separately. Two AI models were developed to recognize liver vessels: the "2-class model" which recognized both hepatic veins and Glissonean pedicles as equivalent vessels and distinguished them from the background class, and the "3-class model" which recognized them all separately. The Feature Pyramid Network was used as a neural network architecture for both models in their semantic segmentation tasks. The models were evaluated using fivefold cross-validation tests, and the Dice coefficient (DC) was used as an evaluation metric. Ten gastroenterological surgeons also evaluated the models qualitatively through rubric. RESULTS: In total, 2421 frames from 48 video clips were extracted. The mean DC value of the 2-class model was 0.789, with a processing speed of 0.094 s. The mean DC values for the hepatic vein and the Glissonean pedicle in the 3-class model were 0.631 and 0.482, respectively. The average processing time for the 3-class model was 0.097 s. Qualitative evaluation by surgeons revealed that false-negative and false-positive ratings in the 2-class model averaged 4.40 and 3.46, respectively, on a five-point scale, while the false-negative, false-positive, and vessel differentiation ratings in the 3-class model averaged 4.36, 3.44, and 3.28, respectively, on a five-point scale. CONCLUSION: We successfully developed deep-learning models that recognize liver vessels in LLR with high accuracy and sufficient processing speed. These findings suggest the potential of a new real-time automated navigation system for LLR.
Subject(s)
Artificial Intelligence , Laparoscopy , Humans , Retrospective Studies , Liver/diagnostic imaging , Liver/surgery , Liver/blood supply , Hepatectomy/methods , Laparoscopy/methodsABSTRACT
Podocyte injury is a critical step toward the progression of renal disease and is often associated with a loss of slit diaphragm proteins, including Podocin. Although there is a possibility that the extracellular domain of these slit diaphragm proteins can be a target for a pathological proteolysis, the precise mechanism driving the phenomenon remains unknown. Here we show that Matriptase, a membrane-anchored protein, was activated at podocytes in CKD patients and mice, whereas Matriptase inhibitors slowed the progression of mouse kidney disease. The mechanism could be accounted for by an imbalance favoring Matriptase over its cognate inhibitor, hepatocyte growth factor activator inhibitor type 1 (HAI-1), because conditional depletion of HAI-1 in podocytes accelerated podocyte injury in mouse model. Matriptase was capable of cleaving Podocin, but such a reaction was blocked by either HAI-1 or dominant-negative Matriptase. Furthermore, the N terminus of Podocin, as a consequence of Matriptase cleavage of Podocin, translocated to nucleoli, suggesting that the N terminus of Podocin might be involved in the process of podocyte injury. Given these observations, we propose that the proteolytic cleavage of Podocin by Matriptase could potentially cause podocyte injury and that targeting Matriptase could be a novel therapeutic strategy for CKD patients.
Subject(s)
Intracellular Signaling Peptides and Proteins/metabolism , Membrane Proteins/metabolism , Podocytes/metabolism , Proteolysis , Renal Insufficiency, Chronic/metabolism , Serine Endopeptidases/metabolism , Animals , Humans , Intracellular Signaling Peptides and Proteins/genetics , Membrane Proteins/genetics , Mice , Mice, Knockout , Podocytes/pathology , Protein Domains , Proteinase Inhibitory Proteins, Secretory/genetics , Proteinase Inhibitory Proteins, Secretory/metabolism , Renal Insufficiency, Chronic/genetics , Renal Insufficiency, Chronic/pathology , Serine Endopeptidases/geneticsABSTRACT
BACKGROUND: School urinary screening has been performed in Japan. METHODS: Ikeda City and Toyono Town introduced, in 2012 and 2013, urinary protein/creatinine (Cr) ratio measurement into the urine-screening protocols designed for students aged between 4 and 15 years. For each student whose urinary protein/Cr ratio was ≥ 0.15 g/gCr (positive case), an appointment was made with a specialist at Ikeda City Hospital. The results of these screening urinalyses conducted through 2018 are summarized. RESULTS: 14,606 junior high and elementary school students aged between 6 and 15 years were included. On average, they underwent 4.16 screening tests. 77 positive cases were detected, and seven students were diagnosed with high-risk chronic kidney disease (CKD). Of these, four underwent renal biopsy, and two, one, and one were diagnosed with IgA nephropathy, MPGN, and FSGS, respectively. In three students, detection of CKD would have been difficult without urinary screening. Incident rates of high-risk CKD and IgA nephropathy are estimated as 11.5 and 3.3 cases/100,000 students/year. 78.0% of positive cases without high-risk CKD showed no urinary abnormality after one year. 2301 kindergarten students aged between 4 and 6 years received an average of 1.74 screening urinalyses; none was positive or high-risk CKD. The estimated cost of detecting one high-risk CKD student whose detection would have been difficult without this screening was 3,156,711 Japanese yen. CONCLUSION: School urinary screening using the urinary protein/Cr ratio can efficiently refer to a specialist. It detects a few children with high-risk CKD early with spending high cost.
Subject(s)
Creatinine/urine , Mass Screening/statistics & numerical data , Proteinuria/urine , Renal Insufficiency, Chronic/diagnosis , Renal Insufficiency, Chronic/epidemiology , Adolescent , Biopsy , Child , Child, Preschool , Female , Glomerulonephritis, IGA/diagnosis , Glomerulonephritis, Membranoproliferative/diagnosis , Glomerulosclerosis, Focal Segmental/diagnosis , Humans , Incidence , Japan/epidemiology , Kidney/pathology , Male , Mass Screening/economics , Mass Screening/methods , Renal Insufficiency, Chronic/urine , SchoolsABSTRACT
To prevent intraoperative organ injury, surgeons strive to identify anatomical structures as early and accurately as possible during surgery. The objective of this prospective observational study was to develop artificial intelligence (AI)-based real-time automatic organ recognition models in laparoscopic surgery and to compare its performance with that of surgeons. The time taken to recognize target anatomy between AI and both expert and novice surgeons was compared. The AI models demonstrated faster recognition of target anatomy than surgeons, especially novice surgeons. These findings suggest that AI has the potential to compensate for the skill and experience gap between surgeons.
Subject(s)
Colorectal Surgery , Digestive System Surgical Procedures , Laparoscopy , Humans , Artificial IntelligenceABSTRACT
Ureolysis-driven microbially induced carbonate precipitation (MICP) has recently received attention for its potential biotechnological applications. However, information on the enrichment and production of ureolytic microbes by using bioreactor systems is limited. Here, we report a low-tech down-flow hanging sponge (DHS) bioreactor system for the enrichment and production of ureolytic microbes. Using this bioreactor system and a yeast extract-based medium containing 0.17 M urea, ureolytic microbes with high potential urease activity (> 10 µmol urea hydrolyzed per min per ml of enrichment culture) were repeatedly enriched under non-sterile conditions. In addition, the ureolytic enrichment obtained in this study showed in vitro calcium carbonate precipitation. Fluorescence in situ hybridization analysis showed the existence of bacteria of the phylum Firmicutes in the bioreactor system. Our data demonstrate that this DHS bioreactor system is a useful system for the enrichment and production of ureolytic microbes for MICP applications.
Subject(s)
Bioreactors/microbiology , Firmicutes/growth & development , Urea/metabolism , Calcium Carbonate , Chemical Precipitation , Firmicutes/classification , In Situ Hybridization, Fluorescence , Urease/analysisABSTRACT
BACKGROUND: The preservation of autonomic nerves is the most important factor in maintaining genitourinary function in colorectal surgery; however, these nerves are not clearly recognisable, and their identification is strongly affected by the surgical ability. Therefore, this study aimed to develop a deep learning model for the semantic segmentation of autonomic nerves during laparoscopic colorectal surgery and to experimentally verify the model through intraoperative use and pathological examination. MATERIALS AND METHODS: The annotation data set comprised videos of laparoscopic colorectal surgery. The images of the hypogastric nerve (HGN) and superior hypogastric plexus (SHP) were manually annotated under a surgeon's supervision. The Dice coefficient was used to quantify the model performance after five-fold cross-validation. The model was used in actual surgeries to compare the recognition timing of the model with that of surgeons, and pathological examination was performed to confirm whether the samples labelled by the model from the colorectal branches of the HGN and SHP were nerves. RESULTS: The data set comprised 12 978 video frames of the HGN from 245 videos and 5198 frames of the SHP from 44 videos. The mean (±SD) Dice coefficients of the HGN and SHP were 0.56 (±0.03) and 0.49 (±0.07), respectively. The proposed model was used in 12 surgeries, and it recognised the right HGN earlier than the surgeons did in 50.0% of the cases, the left HGN earlier in 41.7% of the cases and the SHP earlier in 50.0% of the cases. Pathological examination confirmed that all 11 samples were nerve tissue. CONCLUSION: An approach for the deep-learning-based semantic segmentation of autonomic nerves was developed and experimentally validated. This model may facilitate intraoperative recognition during laparoscopic colorectal surgery.
Subject(s)
Colorectal Surgery , Deep Learning , Laparoscopy , Humans , Pilot Projects , Semantics , Autonomic Pathways/surgery , Laparoscopy/methodsABSTRACT
Although the level of prostaglandin (PG) D(2) in cerebrospinal fluid (CSF) affects the action of D-type prostanoid receptors that promote physiological sleep, the regulatory system of PGD(2) clearance from the CSF is not fully understood. The purpose of this study was to investigate PGD(2) elimination from the CSF via the blood-CSF barrier (BCSFB). The in vivo PGD(2) elimination clearance from the CSF was 16-fold greater than that of inulin, which is considered to reflect CSF bulk flow. This process was inhibited by the simultaneous injection of unlabeled PGD(2). The characteristics of PGD(2) uptake by isolated choroid plexus were, at least partially, consistent with those of PG transporter (PGT) and organic anion transporter 3 (OAT3). Studies using an oocyte expression system showed that PGT and OAT3 were able to mediate PGD(2) transport with a Michaelis-Menten constant of 1.07 and 7.32 µM, respectively. Reverse transcription-polymerase chain reaction and immunohistochemical analyses revealed that PGT was localized on the brush-border membrane of the choroid plexus epithelial cells. These findings indicate that the system regulating the PGD(2) level in the CSF involves PGT- and OAT3-mediated PGD(2) uptake by the choroid plexus epithelial cells, acting as a pathway for PGD(2) clearance from the CSF via the BCSFB.
Subject(s)
Blood-Brain Barrier/metabolism , Organic Anion Transporters, Sodium-Independent/cerebrospinal fluid , Organic Anion Transporters/cerebrospinal fluid , Prostaglandin D2/cerebrospinal fluid , Sleep/physiology , Animals , Biological Transport , Choroid Plexus/metabolism , Chromatography, High Pressure Liquid , Epithelial Cells/metabolism , Female , Immunohistochemistry , Injections, Intraventricular , Male , Metabolic Clearance Rate , Mice , Mice, Inbred Strains , Oocytes/metabolism , Organic Anion Transporters/blood , Organic Anion Transporters/genetics , Organic Anion Transporters, Sodium-Independent/blood , Organic Anion Transporters, Sodium-Independent/genetics , Prostaglandin D2/administration & dosage , Prostaglandin D2/genetics , Prostaglandin D2/pharmacokinetics , Rats , Rats, Wistar , Reverse Transcriptase Polymerase Chain Reaction , Tissue Distribution , Xenopus laevisABSTRACT
Biogenic manganese oxides (BioMnOx) have been receiving increasing attention for the removal of environmental contaminants and recovery of minor metals from water environments. However, the enrichment of heterotrophic Mn(II)-oxidizing microorganisms for BioMnOx production in the presence of fast-growing coexisting heterotrophs is challenging. In our previous work, we revealed that polycaprolactone (PCL), a biodegradable aliphatic polyester, can serve as an effective solid organic substrate to enrich Mn-oxidizing microbial communities under seawater conditions. However, marine BioMnOx-producing bioreactor systems utilizing PCL have not yet been established. Therefore, a laboratory-scale continuous-flow PCL-packed aerated biofilm (PAB) reactor was operated for 238 days to evaluate its feasibility for BioMnOx production under seawater conditions. After the start-up of the reactor, the average dissolved Mn removal rates of 0.4-2.3 mg/L/day, likely caused by Mn(II) oxidation, were confirmed under different influent dissolved Mn concentrations (2.5-14.0 mg/L on average) and theoretical hydraulic retention time (0.19-0.77 day) conditions. The 16S rRNA gene amplicon sequencing analysis suggested the presence of putative Mn(II)-oxidizing and PCL-degrading bacterial lineages in the reactor. Two highly dominant operational units (OTUs) in the packed PCL-associated biofilm were assigned to the genera Marinobacter and Pseudohoeflea, whereas the genus Lewinella and unclassified Alphaproteobacteria OTUs were highly dominant in the MnOx-containing black/dark brown precipitate-associated biofilm formed in the reactor. Excitation-emission matrix fluorescence spectroscopy analysis revealed the production of tyrosine- and tryptophane-like components, which may serve as soluble heterotrophic organic substrates in the reactor. Our findings indicate that PAB reactors are potentially applicable to BioMnOx production under seawater conditions.
ABSTRACT
Importance: Deep learning-based automatic surgical instrument recognition is an indispensable technology for surgical research and development. However, pixel-level recognition with high accuracy is required to make it suitable for surgical automation. Objective: To develop a deep learning model that can simultaneously recognize 8 types of surgical instruments frequently used in laparoscopic colorectal operations and evaluate its recognition performance. Design, Setting, and Participants: This quality improvement study was conducted at a single institution with a multi-institutional data set. Laparoscopic colorectal surgical videos recorded between April 1, 2009, and December 31, 2021, were included in the video data set. Deep learning-based instance segmentation, an image recognition approach that recognizes each object individually and pixel by pixel instead of roughly enclosing with a bounding box, was performed for 8 types of surgical instruments. Main Outcomes and Measures: Average precision, calculated from the area under the precision-recall curve, was used as an evaluation metric. The average precision represents the number of instances of true-positive, false-positive, and false-negative results, and the mean average precision value for 8 types of surgical instruments was calculated. Five-fold cross-validation was used as the validation method. The annotation data set was split into 5 segments, of which 4 were used for training and the remainder for validation. The data set was split at the per-case level instead of the per-frame level; thus, the images extracted from an intraoperative video in the training set never appeared in the validation set. Validation was performed for all 5 validation sets, and the average mean average precision was calculated. Results: In total, 337 laparoscopic colorectal surgical videos were used. Pixel-by-pixel annotation was manually performed for 81â¯760 labels on 38â¯628 static images, constituting the annotation data set. The mean average precisions of the instance segmentation for surgical instruments were 90.9% for 3 instruments, 90.3% for 4 instruments, 91.6% for 6 instruments, and 91.8% for 8 instruments. Conclusions and Relevance: A deep learning-based instance segmentation model that simultaneously recognizes 8 types of surgical instruments with high accuracy was successfully developed. The accuracy was maintained even when the number of types of surgical instruments increased. This model can be applied to surgical innovations, such as intraoperative navigation and surgical automation.
Subject(s)
Colorectal Neoplasms , Laparoscopy , Automation , Humans , Laparoscopy/methods , Neural Networks, Computer , Surgical InstrumentsABSTRACT
Membranous nephropathy associated with malignant neoplasm may remit completely with treatment of the underlying disease. In such cases, recurrence is very rare. However, after a recurrence, attention should be paid to the possible recurrence of the underlying disease.
ABSTRACT
PURPOSE: We sought to profile first-time patients without a referral who sought medical care at the Department of Internal Medicine at a medium-sized acute care hospital in Japan. We anticipated that the analysis would highlight the demand for medical care needs from acute care hospitals and help confirm one of the problems associated with primary care in Japan. PATIENTS AND METHODS: The study population comprised 765 patients who sought outpatient consultation without a referral at "the Department of General Internal Medicine" at the Ikeda City Hospital on Fridays over 4 years. Data on the following variables were collected: age, sex, examination date, reason for encounter (RFE), diagnosis, as well as history of consultation with or without antibiotic treatment at another medical institution for the same RFE. We used the International Classicication of Primary Care, Revised Second edition (ICPC-2-R) codes for RFEs and diagnoses. RESULTS: The main RFE fields were digestive (ICPC-2-R Chapter D), general and unspecified (A), and respiratory (R). The main diagnosis fields were digestive (D), respiratory (R), general and unspecified (A), and musculoskeletal (L). In total, 27.6% of patients had sought consultation at another medical institution for the same RFE. Of these, 64.7% of patients for whom the RFE was cough (ICPC-2-R code, R05), and 72.0% for whom the RFE was fever (A03) were prescribed antibiotics. In total, 62.4% of patients underwent emergency investigations and waited for the results; 4.3% were hospitalized on the same day; and 60.5% were medicated at the initial examination. In 11.5%, the main underlying problem appeared to be psychosomatic. CONCLUSION: We used the ICPC-2-R to analyze the state of first-visit patients without a referral visiting the Department of Internal Medicine at a medium-sized acute care hospital in Japan. Common RFEs were abdominal pain, cough, and fever. A tendency toward overprescription of antibiotics was observed among primary care physicians.
Subject(s)
Colitis/etiology , Colon, Sigmoid , Nephrotic Syndrome/etiology , Adult , Humans , Male , Syphilis/complicationsABSTRACT
Overcoming refractory massive proteinuria remains a clinical and research issue in diabetic nephropathy. This study was designed to investigate the pathogenesis of massive proteinuria in diabetic nephropathy, with a special focus on podocyte autophagy, a system of intracellular degradation that maintains cell and organelle homeostasis, using human tissue samples and animal models. Insufficient podocyte autophagy was observed histologically in patients and rats with diabetes and massive proteinuria accompanied by podocyte loss, but not in those with no or minimal proteinuria. Podocyte-specific autophagy-deficient mice developed podocyte loss and massive proteinuria in a high-fat diet (HFD)-induced diabetic model for inducing minimal proteinuria. Interestingly, huge damaged lysosomes were found in the podocytes of diabetic rats with massive proteinuria and HFD-fed, podocyte-specific autophagy-deficient mice. Furthermore, stimulation of cultured podocytes with sera from patients and rats with diabetes and massive proteinuria impaired autophagy, resulting in lysosome dysfunction and apoptosis. These results suggest that autophagy plays a pivotal role in maintaining lysosome homeostasis in podocytes under diabetic conditions, and that its impairment is involved in the pathogenesis of podocyte loss, leading to massive proteinuria in diabetic nephropathy. These results may contribute to the development of a new therapeutic strategy for advanced diabetic nephropathy.
Subject(s)
Apoptosis , Autophagy , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 2/metabolism , Diabetic Nephropathies/metabolism , Kidney/metabolism , Podocytes/metabolism , Proteinuria/metabolism , Adult , Aged , Animals , Autophagy-Related Protein 5 , Autophagy-Related Protein 7 , Blotting, Western , Cell Line , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/pathology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/pathology , Diabetic Nephropathies/etiology , Diabetic Nephropathies/pathology , Diet, High-Fat , Female , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Intravital Microscopy , Kidney/pathology , Lysosomes/metabolism , Lysosomes/pathology , Male , Membrane Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Microfilament Proteins/metabolism , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Microtubule-Associated Proteins/genetics , Middle Aged , Proteinuria/etiology , Proteinuria/pathology , RNA-Binding Proteins/blood , Rats , Rats, Long-Evans , Severity of Illness Index , Young AdultABSTRACT
Alkyl groups of n-octadecyltrimethoxysilane (ODS) in a self-assembled monolayer on a silicon substrate were oxidized to carboxyl groups by partial irradiation of vacuum ultra-violet light under the photomask, producing a COOH/ODS line pattern. After active esterification of carboxyl groups, two kinds of amine-terminated dendrimers, poly(propyleneimine) and poly(amido amine) (PAMAM) dendrimers, were immobilized on a COOH line through amide-bond so that photolithographic dendrimer/ODS pattern was finally fabricated. Preparation was certified by atomic force microscopy (AFM) and surface-enhanced infrared absorption spectroscopy at transmission mode. Adsorption of linear macromolecules was examined on PAMAM dendrimer/ODS pattern. After adsorption of poly-L-glutamic acid (PGA) at a pH below alpha-helix--random coil transition, rod-shape texture was observed only on the dendrimer line in an AFM image. This texture is an aggregate of alpha-helical PGA. Sodium hyaluronate and DNA were also adsorbed selectively on the dendrimer line, keeping the line profile, although characteristic textures were not observed.
Subject(s)
Organosilicon Compounds/chemistry , Adsorption , Amines/chemistry , Biocompatible Materials/chemistry , DNA/chemistry , Dendrimers , Electrochemistry , Hyaluronic Acid/chemistry , Hydrogen Bonding , Hydrogen-Ion Concentration , Macromolecular Substances/chemistry , Microscopy, Atomic Force , Nucleic Acid Conformation , Polyamines/chemistry , Polyglutamic Acid/chemistry , Polymers/chemistry , Silicon/chemistry , Spectrophotometry , Surface Properties , Ultraviolet RaysABSTRACT
Collagenofibrotic glomerulopathy is a rare glomerular disease characterized by extensive accumulation of atypical type III collagen fibers within the mesangial matrix and subendothelial space. Laboratory evaluation of this disease shows a marked increase in serum procollagen III peptide (P III P) levels. Here, we report the case of two brothers with collagenofibrotic glomerulopathy confirmed by histology. Patient 1 presented with proteinuria and hypertension and patient 2 presented with nephrotic-range proteinuria. Immunohistochemistry revealed strong staining for antibodies to type III collagen in the widened subendothelial spaces in both patients. Electron microscopy revealed numerous collagenous fibers in the mesangium and subendothelial space. P III P levels were elevated in both patients. Most reported cases of collagenofibrotic glomerulopathy, including the adult-onset type, have been sporadic. Within the limits of our literature search, this is only the third report of adult siblings with collagenofibrotic glomerulopathy confirmed by histology. This report indicates that it may be beneficial to measure serum P III P levels in the siblings of patients diagnosed with adult-onset collagenofibrotic glomerulopathy.
ABSTRACT
Organosilane self-assembled monolayers (SAMs) have been applied to resist materials for nanolithography based on scanning probe microscopy. An organosilane SAM was prepared on Si substrates from a precursor, that is octadecyltrimethoxysilane. Using an atomic force microscope with a conductive probe, current was injected from the probe into the SAM-covered Si substrate so that the SAM was locally degraded at the probe-contacting point. Nanoscale patterns drawn on the SAM was clearly imaged by lateral force microscopy. The patterning could be conducted in air while, in vacuum at the order of 10(-6) Torr, no detectable patterns were fabricated. The presence of adsorbed water at the probe/sample junction was confirmed to be crucial for the patterning of the SAM/Si. Its mechanism was, thus, ascribed to electrochemical reactions of both the SAM and Si with adsorbed water.
ABSTRACT
Surface potentials of Si substrates covered with a organosilane self-assembled monolayers (SAMs) were measured with reference to the substrate uncovered with the SAM using Kelvin probe force microscopy. Based on a photolithographic technique, the reference surface was prepared in a micrometer scale on each of the samples. SAMs were prepared from n-octadecyltrimethoxysilane [ODS: CH3(CH2)17Si(OCH3)3], 3,3,3-trifluoropropyltrimethoxysilane [FAS3: CF3(CH2)2Si(OCH3)3], heptadecafluoro-1,1,2,2-tetahydro-decyl-1-trimethoxysilane [FAS17: CF3(CF2)7(CH2)2Si(OCH3)3] or n-(6-aminohexyl) aminopropyltrimethoxysilane [AHAPS: H2N(CH2)6NH(CH2)3Si(OCH3)3) by chemical vapor deposition. Potentials of the surfaces covered with ODS-, FAS3- and FAS17-SAMs became more negative than the uncovered Si substrate, while the surface covered with AHAPS-SAM showed a more positive surface potential than the reference. The potential contrasts of these SAMs to the reference were -25, -170, -225 and +50 mV for ODS-, FAS3-, FAS17- and AHAPS-SAMs, respectively. These results almost agreed with potentials expected from the dipole moments of the corresponding precursor molecules estimated by ab initio molecular orbital calculation, except for FAS3-SAM. Despite FAS3 molecule having a larger dipole moment than FAS17 molecule, the surface potential contrast of FAS3-SAM was smaller than that of FAS17-SAM, since surface coverage of FAS3-SAM was relatively incomplete compared with the other SAMs.
ABSTRACT
Naturally occurring prostaglandin E2 (PGE2) plays a role in inflammatory responses through eicosanoid signaling pathways. PGE2 is impermeable to cell membranes at physiological pH and needs solute carrier across the membranes; however, it remains unclear how intercellular concentrations of PGE2 are regulated under the condition of inflammation. We aimed to clarify a role of organic anion-transporting polypeptide 2A1 (OATP2A1/SLCO2A1), also known as prostaglandin transporter (PGT), in PGE2 release from cells. Human bronchial epithelial BEAS-2B cells were treated with lipopolysaccharide (LPS), and PGT inhibitors were tested to evaluate contribution of PGT to PGE2 release by assessing its extracellular concentration and characterizing PGT-mediated PGE2 efflux in Xenopus laevis oocytes. As a result, LPS elevated mRNA expression of a pro-inflammatory cytokine IL6 and extracellular concentration of PGE2 in human bronchial epithelial BEAS-2B cells. PGT inhibitors tested (e.g. bromocresol green (BCG), bromosulfophthalein (BSP), and PGB1) significantly inhibited efflux of PGE2 from oocytes expressing PGT. Similarly, the amount of released PGE2 from the BEAS-2B cells decreased in the presence of BCG and BSP by 45 and 44% respectively while TGBz increased the concentration by 71%, suggesting that PGT mediates the release. In conclusion, these results imply a role of PGT in regulating intra- and extracellular concentrations of PGE2 in response to cells under inflammatory conditions.
Subject(s)
Bronchi/metabolism , Dinoprostone/metabolism , Epithelial Cells/metabolism , Organic Anion Transporters/metabolism , Signal Transduction/physiology , 3T3-L1 Cells , Animals , Bronchi/cytology , Bronchi/drug effects , Cell Line , Epithelial Cells/cytology , Epithelial Cells/drug effects , Humans , Interleukin-6/metabolism , Lipopolysaccharides/pharmacology , Mice , Organic Anion Transporters/genetics , Signal Transduction/drug effects , Xenopus laevisABSTRACT
BACKGROUND: Annual urinary screening is conducted at municipal kindergartens, elementary schools, and junior high schools in Ikeda City, Osaka, Japan (Ikeda City School System), and the results are reviewed by a general physician, but standards for when to recommend specialist referral have not been clear. METHODS: In all children attending the Ikeda City School System in 2012, dipstick urinalysis of a first-morning urine specimen was recommended once or twice, and if a second urinalysis showed proteinuria (≥1+), the urinary protein/creatinine ratio was measured. If this showed ≥0.2 g/g of creatinine (g/gCr), it was recommended that the child be evaluated by a specialist at Ikeda City Hospital. RESULTS: Urinary screening was performed in about 20% (388) of kindergarten, about 90% (5363) of elementary school, and about 86% (2523) of junior high school children living in Ikeda City. Urine samples were obtained from 387, 5349, and 2476 children, respectively. The urinary protein/creatinine ratio was ≥0.2 g/gCr in 13 children, including 1 elementary and 12 junior high children. In these 13 children, chronic nephritic syndrome (CNS) was suspected in 6 junior high school children, and of these, this was a new finding in 5, and renal biopsy was indicated in 3. In Ikeda City, the prevalence of CNS in elementary school children was <0.03%, the prevalence of CNS in junior high school children was 0.29%, and a renal biopsy was indicated in 0.14%. By eliminating the costs associated with assessment of the results by the Ikeda Medical Association, and by directly contracting with the testing company, the expenses paid by Ikeda City for the system itself decreased from 2,508,619 yen to 966,157 yen. CONCLUSIONS: Incorporating the urinary protein/creatinine ratio into the school urinary screening system in the Ikeda City School System and clarifying standards for specialist referral has enabled restructuring of the system so that is efficient and its effectiveness can be assessed.