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1.
Differentiation ; 125: 18-26, 2022.
Article in English | MEDLINE | ID: mdl-35349880

ABSTRACT

Mouse embryonic stem cells (mESCs) are characterized by self-renewal and pluripotency and can undergo differentiation into the three germ layers (ectoderm, mesoderm, and endoderm). Melanoma-associated antigen D1 (Maged1), which is expressed in all developing and adult tissues, modulates tissue regeneration and development. In the present study, we examined the expression and function of Maged1 in mESCs. Maged1 protein and mRNA expression increased during mESC differentiation. The pluripotency of mESCs was significantly reduced through extracellular signal-regulated kinase 1/2 phosphorylation upon knockdown of Maged1, and through G1 cell cycle arrest during cell division, resulting in significantly reduced mESC proliferation. Moreover, the diameter of the embryoid bodies was significantly reduced, accompanied by increased levels of ectodermal differentiation markers and decreased levels of mesodermal and endodermal differentiation markers. Maged1-knockdown mESC lines showed significantly reduced teratoma volumes and inhibition of teratoma formation in nude mice. Additionally, we observed increased ectodermal markers but decreased mesodermal and endodermal markers in teratoma tissues. These findings show that Maged1 affects mESC pluripotency, proliferation, cell cycle, and differentiation, thereby contributing to our understanding of the basic molecular biological mechanisms and potential roles of Maged1 as a regulator of various mESC properties.


Subject(s)
Mouse Embryonic Stem Cells , Animals , Antigens, Differentiation/metabolism , Cell Cycle/genetics , Cell Death , Cell Differentiation/genetics , Cell Division , Mice , Mice, Nude , Mouse Embryonic Stem Cells/cytology , Mouse Embryonic Stem Cells/metabolism , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Teratoma/genetics , Teratoma/metabolism , Teratoma/pathology
2.
Appl Microbiol Biotechnol ; 106(2): 663-673, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34971409

ABSTRACT

For the efficient production of heterologous proteins in the yeast Saccharomyces cerevisiae, we screened for a novel fusion partner from the yeast secretome. From twenty major proteins identified from the yeast secretome, we selected Scw4p, a cell wall protein with similarity to glucanase, and modified to develop a general fusion partner for the secretory expression of heterologous proteins in yeast. The optimal size of the SCW4 gene to act as an efficient fusion partner was determined by C-terminal truncation analysis; two of the variants, S1 (truncated at codon 115Q) and S2 (truncated at codon 142E), were further used for the secretion of heterologous proteins. When fused with S2, the secretion of three target proteins (hGH, exendin-4, and hPTH) significantly increased. Conserved O-glycosylation sites (Ser/Thr-rich domain) and hydrophilic sequences of S2 were deemed important for the function of S2 as a secretion fusion partner. Approximately 5 g/L of the S2-exendin-4 fusion protein was obtained from fed-batch fermentation. Intact target proteins were easily purified by affinity chromatography after in vitro processing of the fusion partner. This system may be of general application for the secretory production of heterologous proteins in S. cerevisiae. KEY POINTS : • Target proteins were efficiently secreted with their N-terminus fused to Scw4p. • O-glycosylation and hydrophilic stretches in Scw4p were important for protein secretion. • A variant of Scw4p (S2) was successfully applied for the secretory expression of heterologous proteins.


Subject(s)
Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Secretome
3.
J Xray Sci Technol ; 30(3): 549-566, 2022.
Article in English | MEDLINE | ID: mdl-35253722

ABSTRACT

BACKGROUND: Dual-energy computed tomography (DECT) is a widely used and actively researched imaging modality that can estimate the physical properties of an object more accurately than single-energy CT (SECT). Recently, iterative reconstruction methods called one-step methods have received attention among various approaches since they can resolve the intermingled limitations of the conventional methods. However, the one-step methods typically have expensive computational costs, and their material decomposition performance is largely affected by the accuracy in the spectral coefficients estimation. OBJECTIVE: In this study, we aim to develop an efficient one-step algorithm that can effectively decompose into the basis material maps and is less sensitive to the accuracy of the spectral coefficients. METHODS: By use of a new loss function that employs the non-linear forward model and the weighted squared errors, we propose a one-step reconstruction algorithm named generalized simultaneous algebraic reconstruction technique (GSART). The proposed algorithm was compared with the image-domain material decomposition and other existing one-step reconstruction algorithm. RESULTS: In both simulation and experimental studies, we demonstrated that the proposed algorithm effectively reduced the beam-hardening artifacts thereby increasing the accuracy in the material decomposition. CONCLUSIONS: The proposed one-step reconstruction for material decomposition in dual-energy CT outperformed the image-domain approach and the existing one-step algorithm. We believe that the proposed method is a practically very useful addition to the material-selective image reconstruction field.

4.
Int J Mol Sci ; 22(5)2021 Feb 26.
Article in English | MEDLINE | ID: mdl-33652881

ABSTRACT

Senescence marker protein 30 (SMP30) is a cell survival factor playing an important role in vitamin C synthesis and antiapoptosis. Moreover, its cytoprotective role suggests a possibility to be related to cancer cell survival. Mammary carcinoma is a common cancer in both humans and animals. Because of its histopathological diversity, especially in the early stage, histopathological diagnosis may be complicated; therefore, a diagnostic marker is helpful for confirmation. The present study analyzed the expression pattern of SMP30 in mammary carcinoma in humans, dogs, and cats. Immunohistochemistry, immunofluorescence, and western blot analysis were used to investigate SMP30 expression patterns. The expression was specifically observed in neoplastic glandular epithelial cells. The expression increased with the malignancy of glandular epithelial cells with a highly proliferative status. However, SMP30 expression was low in normal mammary gland tissues or well-differentiated adenoma tissues. The patterns were consistently reproduced in canine primary mammary carcinoma cells and MCF-7 and MDA-MB-231 human carcinoma cell lines. This study provides useful information to understand SMP30 expression in various stages of mammary carcinoma and to suggest its utility as a pan-species diagnostic marker, thereby helping to establish strategies for diagnosing mammary carcinoma in several species.


Subject(s)
Breast Neoplasms/pathology , Calcium-Binding Proteins/analysis , Cat Diseases/pathology , Dog Diseases/pathology , Intracellular Signaling Peptides and Proteins/analysis , Mammary Neoplasms, Animal/pathology , Animals , Biomarkers, Tumor/analysis , Breast/pathology , Breast Neoplasms/diagnosis , Cat Diseases/diagnosis , Cats , Cell Line, Tumor , Dog Diseases/diagnosis , Dogs , Female , Humans , MCF-7 Cells , Mammary Neoplasms, Animal/diagnosis , Prognosis
5.
J Proteome Res ; 19(1): 391-400, 2020 01 03.
Article in English | MEDLINE | ID: mdl-31689115

ABSTRACT

Motile cilia of multiciliated epithelial cells have important roles in animal development and cell homeostasis. Although several studies have identified and reported proteins localized in this complex organelle and the related immotile primary cilia from various cell types, it is still challenging to isolate high quantities of ciliary proteins for proteomic analysis. In this study, African clawed frog (Xenopus laevis) embryos, which have many multiciliated cells in the epidermis, were treated with a simple ionic buffer to identify 1009 proteins conserved across vertebrates; these proteins were putatively localized in motile cilia. Using two ciliary proteome databases, we confirmed that previously validated cilia-associated proteins are highly enriched in our ciliary proteome. Proteins localized at the transition zone and Ellis-van Creveld zone, which are distinct regions at the base of cilia, near the junction with the apical cell surface, were isolated using our method. Among the newly identified ciliary proteins, we report that KRT17 may have an unrecognized function in motile cilia. Hence, the method developed in this study would be useful for understanding the ciliary proteome.


Subject(s)
Cilia/metabolism , Keratin-17/metabolism , Proteomics/methods , Xenopus Proteins/analysis , Animals , Cilia/physiology , Embryo, Nonmammalian/cytology , Epidermis/metabolism , Female , Keratin-17/genetics , Male , Reproducibility of Results , Xenopus/embryology , Xenopus Proteins/metabolism , Xenopus laevis/embryology
6.
Mol Cell Proteomics ; 17(5): 948-960, 2018 05.
Article in English | MEDLINE | ID: mdl-29414759

ABSTRACT

Overactive bladder (OAB) syndrome is a condition that has four symptoms: urgency, urinary frequency, nocturia, and urge incontinence and negatively affects a patient's life. Recently, it is considered that the urinary bladder urothelium is closely linked to pathogenesis of OAB. However, the mechanisms of pathogenesis of OAB at the molecular level remain poorly understood, mainly because of lack of modern molecular analysis. The goal of this study is to identify a potential target protein that could act as a predictive factor for effective diagnosis and aid in the development of therapeutic strategies for the treatment of OAB syndrome. We produced OAB in a rat model and performed the first proteomic analysis on the mucosal layer (urothelium) of the bladders of sham control and OAB rats. The resulting data revealed the differential expression of 355 proteins in the bladder urothelium of OAB rats compared with sham subjects. Signaling pathway analysis revealed that the differentially expressed proteins were mainly involved in the inflammatory response and apoptosis. Our findings suggest a new target for accurate diagnosis of OAB that can provide essential information for the development of drug treatment strategies as well as establish criteria for screening patients in the clinical environment.


Subject(s)
Proteomics/methods , Urinary Bladder Neck Obstruction/complications , Urinary Bladder Neck Obstruction/metabolism , Urinary Bladder, Overactive/etiology , Urinary Bladder, Overactive/metabolism , Urothelium/metabolism , Animals , Biomarkers/metabolism , Disease Models, Animal , Female , Molecular Sequence Annotation , Organ Size , Protein Interaction Maps , Proteome/metabolism , Rats, Sprague-Dawley , Reproducibility of Results , Signal Transduction , Up-Regulation , Urinary Bladder/metabolism , Urinary Bladder/pathology , Urothelium/pathology
7.
J Nanosci Nanotechnol ; 19(10): 6429-6436, 2019 10 01.
Article in English | MEDLINE | ID: mdl-31026973

ABSTRACT

We have developed and characterized a highly manufacturable nanoporous Ag film using a custom-made sputtering system for a surface enhanced Raman scattering substrate for biosensors. The Raman response property of the Ag nanoporous thin film peaked at the same characteristic wavelength as a commercial specimen with an intensity that was 1.5 times higher. We also observed the characteristics of the Ag nanoporous films prepared in this study up to 10 picomole of Rhodamine 6G concentration and 1 picomole and 0.1 picomole using additional signal processing methods. The Raman intensity was at least 10 times higher than the intensity of the Ag nanoporous thin film itself, at densities of 4.3 × 104 cps, 4.0 × 104 cps, 2.9 × 104 cps, and 1.4 × 104 cps. The characteristic peak wavelength also differed. The Raman intensity peak was highest at a wave number of 1513/cm, regardless of the thickness of the Ag nanoporous film, and was found to have a large peak, in the order of 1364/cm, 1314/cm, 612/cm, and 1653/cm. Therefore, it can be confirmed that the Ag nanoporous thin film proposed in this paper can be used as a SERS substrate.

8.
Mar Drugs ; 16(8)2018 Aug 18.
Article in English | MEDLINE | ID: mdl-30126169

ABSTRACT

Ultraviolet (UV) B exposure induces DNA damage and production of reactive oxygen species (ROS), which causes skin photoaging through signaling pathways of inflammation and modulation of extracellular matrix remodeling proteins, collagens, and matrix metalloproteinase (MMP). As low molecular-weight fucoidan (LMF) has potential antioxidant and anti-inflammatory properties, we examined the protective effects of LMF against UVB-induced photoaging. A UVB-irradiated mouse model was topically treated with myricetin or LMF at 2.0, 1.0 and 0.2 mg/cm² (LMF2.0, LMF1.0 and LMF0.2, respectively) once a day for 15 weeks. Wrinkle formation, inflammation, oxidative stress, MMP expression, and apoptosis in the treated regions were compared with those in a distilled water-treated photoaging model (UVB control). LMF treatments, particularly LMF2.0 and LMF1.0, significantly inhibited the wrinkle formation, skin edema, and neutrophil recruitment into the photo-damaged lesions, compared with those in the UVB control. While LMF decreased interleukin (IL)-1ß release, it increased IL-10. The LMF treatment inhibited the oxidative stresses (malondialdehyde and superoxide anion) and enhanced endogenous antioxidants (glutathione). Additionally, LMF reduced the mRNA expression of MMP-1, 9, and 13. The histopathological analyses revealed the anti-photoaging effects of LMF exerted via its antioxidant, anti-apoptotic, and MMP-9-inhibiting effects. These suggest that LMF can be used as a skin-protective remedy for photoaging.


Subject(s)
Polysaccharides/pharmacology , Skin Aging/drug effects , Ultraviolet Rays/adverse effects , Animals , Antioxidants/pharmacology , Apoptosis/drug effects , Collagen/metabolism , Female , Interleukin-10/metabolism , Membrane Proteins/metabolism , Metalloendopeptidases/metabolism , Mice , Mice, Hairless , Molecular Weight , Oxidative Stress/drug effects , Reactive Oxygen Species/metabolism , Skin/drug effects , Skin/metabolism
9.
Int J Mol Sci ; 16(5): 9167-95, 2015 Apr 23.
Article in English | MEDLINE | ID: mdl-25915030

ABSTRACT

The hyperthermophilic archaeon Thermococcus onnurineus NA1 has been shown to produce H2 when using CO, formate, or starch as a growth substrate. This strain can also utilize elemental sulfur as a terminal electron acceptor for heterotrophic growth. To gain insight into sulfur metabolism, the proteome of T. onnurineus NA1 cells grown under sulfur culture conditions was quantified and compared with those grown under H2-evolving substrate culture conditions. Using label-free nano-UPLC-MSE-based comparative proteomic analysis, approximately 38.4% of the total identified proteome (589 proteins) was found to be significantly up-regulated (≥1.5-fold) under sulfur culture conditions. Many of these proteins were functionally associated with carbon fixation, Fe-S cluster biogenesis, ATP synthesis, sulfur reduction, protein glycosylation, protein translocation, and formate oxidation. Based on the abundances of the identified proteins in this and other genomic studies, the pathways associated with reductive sulfur metabolism, H2-metabolism, and oxidative stress defense were proposed. The results also revealed markedly lower expression levels of enzymes involved in the sulfur assimilation pathway, as well as cysteine desulfurase, under sulfur culture condition. The present results provide the first global atlas of proteome changes triggered by sulfur, and may facilitate an understanding of how hyperthermophilic archaea adapt to sulfur-rich, extreme environments.


Subject(s)
Hydrogen/metabolism , Proteome , Proteomics , Sulfur/metabolism , Thermococcus/metabolism , Archaeal Proteins/genetics , Archaeal Proteins/metabolism , Carbon Dioxide/metabolism , Gene Expression , Gene Expression Regulation, Archaeal , Glycosylation , Lipids/biosynthesis , Oxidation-Reduction , Protein Transport , Proteolysis , Proteomics/methods , Thermococcus/genetics
10.
Mol Cell Proteomics ; 11(6): M111.015420, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22232491

ABSTRACT

Thermococcus onnurineus NA1, a sulfur-reducing hyperthermophilic archaeon, is capable of H(2)-producing growth, considered to be hydrogenogenic carboxydotrophy. Utilization of formate as a sole energy source has been well studied in T. onnurineus NA1. However, whether formate can be used as its carbon source remains unknown. To obtain a global view of the metabolic characteristics of H(2)-producing growth, a quantitative proteome analysis of T. onnurineus NA1 grown on formate, CO, and starch was performed by combining one-dimensional SDS-PAGE with nano UPLC-MS(E). A total of 587 proteins corresponding to 29.7% of the encoding genes were identified, and the major metabolic pathways (especially energy metabolism) were characterized at the protein level. Expression of glycolytic enzymes was common but more highly induced in starch-grown cells. In contrast, enzymes involved in key steps of the gluconeogenesis and pentose phosphate pathways were strongly up-regulated in formate-grown cells, suggesting that formate could be utilized as a carbon source by T. onnurineus NA1. In accordance with the genomic analysis, comprehensive proteomic analysis also revealed a number of hydrogenase clusters apparently associated with formate metabolism. On the other hand, CODH and CO-induced hydrogenases belonging to the Hyg4-II cluster, as well as sulfhydrogenase-I and Mbx, were prominently expressed during CO culture. Our data suggest that CO can be utilized as a sole energy source for H(2) production via an electron transport mechanism and that CO(2) produced from catabolism or CO oxidation by CODH and CO-induced hydrogenases may subsequently be assimilated into the organic carbon. Overall, proteomic comparison of formate- and CO-grown cells with starch-grown cells revealed that a single carbon compound, such as formate and CO, can be utilized as an efficient substrate to provide cellular carbon and/or energy by T. onnurineus NA1.


Subject(s)
Archaeal Proteins/metabolism , Carbohydrate Metabolism , Proteome/metabolism , Thermococcus/metabolism , Adaptation, Biological , Amino Acids/metabolism , Carbon Monoxide/metabolism , Culture Media , Formates/metabolism , Hydrogen/metabolism , Hydrogenase/genetics , Hydrogenase/metabolism , Metabolic Networks and Pathways , Multigene Family , Starch/metabolism , Stress, Physiological , Thermococcus/growth & development , Thermococcus/physiology
11.
Chemosphere ; 361: 142430, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38844105

ABSTRACT

In the present study, algicidal bacteria cultivated in an aqueous medium were utilized as a surface modification agent to develop an efficient adsorbent for the removal of Microcystis aeruginosa. The modification considerably enhanced M. aeruginosa cell removal efficiency. Moreover, the introduction of bio-compounds ensured specificity in the removal of M. aeruginosa. Additionally, the cyanotoxin release and acute toxicity tests demonstrated that the adsorption process using the developed adsorbent is environmentally safe. Furthermore, the practical feasibility of the adsorptive removal of M. aeruginosa was confirmed through cell removal tests performed using the developed adsorbent in a scaled-up reactor (50 L and 10 tons). In these tests, the effects of the adsorbent application type, water temperature, and initial cell concentration on the M. aeruginosa removal efficiency were evaluated. The results of this study provide novel insights into the valorization strategy of biological algicides repurposed as adsorbents, and provide practical operational data for effective M. aeruginosa removal in scaled-up conditions.


Subject(s)
Microcystis , Adsorption , Microcystins/chemistry , Microcystins/metabolism , Microcystins/isolation & purification , Cyanobacteria/metabolism , Water Purification/methods
12.
Article in English | MEDLINE | ID: mdl-38376819

ABSTRACT

Human intestinal epithelial cells (IECs) play an important role in maintaining gut homeostasis by producing antimicrobial peptides (AMPs). Bacillus subtilis, a commensal bacterium, is considered a probiotic. Although its protective effects on intestinal health are widely reported, the key component of B. subtilis responsible for its beneficial effects remains elusive. In this study, we tried to identify the key molecules responsible for B. subtilis-induced AMPs and their molecular mechanisms in a human IEC line, Caco-2. B. subtilis increased human beta defensin (HBD)-2 mRNA expression in a dose- and time-dependent manner. Among the B. subtilis microbe-associated molecular patterns, lipoprotein (LPP) substantially increased the mRNA expression and protein production of HBD-2, whereas lipoteichoic acid and peptidoglycan did not show such effects. Those results were confirmed in primary human IECs. In addition, both LPP recognition and HBD-2 secretion mainly took place on the apical side of fully differentiated and polarized Caco-2 cells through Toll-like receptor 2-mediated JNK/p38 MAP kinase/AP-1 and NF-κB pathways. HBD-2 efficiently inhibited the growth of the intestinal pathogens Staphylococcus aureus and Bacillus cereus. Furthermore, LPPs pre-incubated with lipase or proteinase K decreased LPP-induced HBD-2 expression, suggesting that the lipid and protein moieties of LPP are crucial for HBD-2 expression. Q Exactive Plus mass spectrometry identified 35 B. subtilis LPP candidates within the LPP preparation, and most of them were ABC transporters. Taken together, these results suggest that B. subtilis promotes HBD-2 secretion in human IECs mainly with its LPPs, which might enhance the protection from intestinal pathogens.

13.
J Vet Sci ; 25(2): e22, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38568824

ABSTRACT

BACKGROUND: Achilles tendon is composed of dense connective tissue and is one of the largest tendons in the body. In veterinary medicine, acute ruptures are associated with impact injury or sharp trauma. Healing of the ruptured tendon is challenging because of poor blood and nerve supply as well as the residual cell population. Platelet-rich plasma (PRP) contains numerous bioactive agents and growth factors and has been utilized to promote healing in bone, soft tissue, and tendons. OBJECTIVE: The purpose of this study was to evaluate the healing effect of PRP injected into the surrounding fascia of the Achilles tendon after allograft in rabbits. METHODS: Donor rabbits (n = 8) were anesthetized and 16 lateral gastrocnemius tendons were fully transected bilaterally. Transected tendons were decellularized and stored at -80°C prior to allograft. The allograft was placed on the partially transected medial gastrocnemius tendon in the left hindlimb of 16 rabbits. The allograft PRP group (n = 8) had 0.3 mL of PRP administered in the tendon and the allograft control group (n = 8) did not receive any treatment. After 8 weeks, rabbits were euthanatized and allograft tendons were transected for macroscopic, biomechanical, and histological assessment. RESULTS: The allograft PRP group exhibited superior macroscopic assessment scores, greater tensile strength, and a histologically enhanced healing process compared to those in the allograft control group. CONCLUSIONS: Our results suggest administration of PRP on an allograft tendon has a positive effect on the healing process in a ruptured Achilles tendon.


Subject(s)
Achilles Tendon , Platelet-Rich Plasma , Tendon Injuries , Rabbits , Animals , Achilles Tendon/surgery , Achilles Tendon/injuries , Achilles Tendon/pathology , Tendon Injuries/therapy , Tendon Injuries/veterinary , Tendon Injuries/pathology , Wound Healing , Allografts/pathology
14.
Proteomics ; 13(7): 1164-79, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23349036

ABSTRACT

Type 2 diabetes mellitus (T2DM) is the most prevalent and serious metabolic disease affecting people worldwide. T2DM results from insulin resistance of the liver, muscle, and adipose tissue. In this study, we used proteomic and bioinformatic methodologies to identify novel hepatic membrane proteins that are related to the development of hepatic insulin resistance, steatosis, and T2DM. Using FT-ICR MS, we identified 95 significantly differentially expressed proteins in the membrane fraction of normal and T2DM db/db mouse liver. These proteins are primarily involved in energy metabolism pathways, molecular transport, and cellular signaling, and many of them have not previously been reported in diabetic studies. Bioinformatic analysis revealed that 16 proteins may be related to the regulation of insulin signaling in the liver. In addition, six proteins are associated with energy stress-induced, nine proteins with inflammatory stress-induced, and 14 proteins with endoplasmic reticulum stress-induced hepatic insulin resistance. Moreover, we identified 19 proteins that may regulate hepatic insulin resistance in a c-Jun amino-terminal kinase-dependent manner. In addition, three proteins, 14-3-3 protein beta (YWHAB), Slc2a4 (GLUT4), and Dlg4 (PSD-95), are discovered by comprehensive bioinformatic analysis, which have correlations with several proteins identified by proteomics approach. The newly identified proteins in T2DM should provide additional insight into the development and pathophysiology of hepatic steatosis and insulin resistance, and they may serve as useful diagnostic markers and/or therapeutic targets for these diseases.


Subject(s)
Computational Biology/methods , Diabetes Mellitus, Type 2/metabolism , Liver/metabolism , Membrane Proteins/metabolism , Proteome/metabolism , Proteomics/methods , Animals , Endoplasmic Reticulum Stress , Inflammation/metabolism , Insulin Resistance , JNK Mitogen-Activated Protein Kinases/metabolism , Lipid Metabolism , Male , Mass Spectrometry , Mice , Mice, Inbred C57BL , Protein Interaction Maps , Reproducibility of Results
15.
Med Phys ; 50(12): 7498-7512, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37669510

ABSTRACT

BACKGROUND: The bowtie-filter in cone-beam CT (CBCT) causes spatially nonuniform x-ray beam often leading to eclipse artifacts in the reconstructed image. The artifacts are further confounded by the patient scatter, which is therefore patient-dependent as well as system-specific. PURPOSE: In this study, we propose a dual-domain network for reducing the bowtie-filter-induced artifacts in CBCT images. METHODS: In the projection domain, the network compensates for the filter-induced beam-hardening that are highly related to the eclipse artifacts. The output of the projection-domain network was used for image reconstruction and the reconstructed images were fed into the image-domain network. In the image domain, the network further reduces the remaining cupping artifacts that are associated with the scatter. A single image-domain-only network was also implemented for comparison. RESULTS: The proposed approach successfully enhanced soft-tissue contrast with much-reduced image artifacts. In the numerical study, the proposed method decreased perceptual loss and root-mean-square-error (RMSE) of the images by 84.5% and 84.9%, respectively, and increased the structure similarity index measure (SSIM) by 0.26 compared to the original input images on average. In the experimental study, the proposed method decreased perceptual loss and RMSE of the images by 87.2% and 92.1%, respectively, and increased SSIM by 0.58 compared to the original input images on average. CONCLUSIONS: We have proposed a deep-learning-based dual-domain framework to reduce the bowtie-filter artifacts and to increase the soft-tissue contrast in CBCT images. The performance of the proposed method has been successfully demonstrated in both numerical and experimental studies.


Subject(s)
Neural Networks, Computer , Quality Improvement , Humans , Cone-Beam Computed Tomography/methods , Image Processing, Computer-Assisted/methods , X-Rays , Algorithms , Phantoms, Imaging , Artifacts
16.
Vet Sci ; 10(11)2023 Oct 27.
Article in English | MEDLINE | ID: mdl-37999457

ABSTRACT

Intra-abdominal pressure (IAP) elevation during capnoperitoneum can cause adverse cardiovascular and respiratory effects. This study aimed to determine if a sequentially increased IAP affects cardiovascular and respiratory variables in anesthetized dogs and evaluate the effects of the constant-rate infusion of dexmedetomidine (Dex) on cardiovascular and respiratory variables with increased IAP. Five dogs were anesthetized and instrumented, and a Veress needle was equipped to adjust the IAP using a carbon dioxide insufflator. Stabilization was conducted for 1 h, and physiological variables were measured at IAPs of 0, 5, 10, 15, and 20 mmHg and after desufflation. After the washout period, the dogs underwent similar procedures along with a constant-rate infusion of dexmedetomidine. The cardiovascular effects of increased IAP up to 20 mmHg were not significant in healthy beagle dogs and those administered with dexmedetomidine. When comparing the control and dexmedetomidine groups, the overall significant effects of dexmedetomidine were noted on heart rate, cardiac output, and systemic vascular resistance during the experiment. Respiratory effects were not observed during abdominal insufflation when compared between different IAPs and between the two groups. Overall, an increased IAP of up to 20 mmHg did not significantly affect cardiovascular and respiratory variables in both the control and dexmedetomidine groups. This study suggests that the administration of a dexmedetomidine infusion is applicable in laparoscopic procedures in healthy dogs.

17.
Int J Mol Sci ; 13(12): 17230-43, 2012 Dec 17.
Article in English | MEDLINE | ID: mdl-23247284

ABSTRACT

Type 2 diabetes is a chronic metabolic disease that results from insulin resistance in the liver, muscle, and adipose tissue and relative insulin deficiency. The endoplasmic reticulum (ER) plays a crucial role in the regulation of the cellular response to insulin. Recently, ER stress has been known to reduce the insulin sensitivity of the liver and lead to type 2 diabetes. However, detailed mechanisms of ER stress response that leads to type 2 diabetes remains unknown. To obtain a global view of ER function in type 2 diabetic liver and identify proteins that may be responsible for hepatic ER stress and insulin resistance, we performed proteomics analysis of mouse liver ER using nano UPLC-MSE. A total of 1584 proteins were identified in control C57 and type 2 diabetic db/db mice livers. Comparison of the rER and sER proteomes from normal mice showed that proteins involved in protein synthesis and metabolic process were enriched in the rER, while those associated with transport and cellular homeostasis were localized to the sER. In addition, proteins involved in protein folding and ER stress were found only in the rER. In the livers of db/db mice, however, the functions of the rER and sER were severely disrupted, including the capacity to resolve ER stress. These results provide new insight into the research on hepatic insulin resistance and type 2 diabetes and are suggestive of the potential use of the differentially expressed hepatic ER proteins as biomarkers for hepatic insulin resistance and type 2 diabetes.


Subject(s)
Diabetes Mellitus, Type 2/metabolism , Endoplasmic Reticulum Stress , Endoplasmic Reticulum/metabolism , Insulin Resistance , Liver/metabolism , Proteome/metabolism , Animals , Biomarkers/metabolism , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/pathology , Endoplasmic Reticulum/genetics , Endoplasmic Reticulum/pathology , Liver/pathology , Mice , Mice, Mutant Strains
18.
Anim Biosci ; 35(12): 1850-1859, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35507843

ABSTRACT

OBJECTIVE: The quantitative reverse transcription polymerase chain reaction (qPCR) is the most accurate and reliable technique for analysis of gene expression. Endogenous reference genes (RGs) have been used to normalize qPCR data, although their expression may vary in different tissues and experimental conditions. Verification of the stability of RGs in selected samples is a prerequisite for reliable results. Therefore, we attempted to identify the most stable RGs in the hypothalamic-pituitary-gonadal (HPG) axis in sows. METHODS: The cycle threshold values of nine commonly used RGs (18S, HPRT1, GAPDH, RPL4, PPIA, B2M, YWHAZ, ACTB, and SDHA) from HPG axis-related tissues in the domestic sows in the different stages of estrus cycle were analyzed using two RG-finding programs, geNorm and Normfinder, to rank the stability of the pool of RGs. In addition, the effect of the most and least stable RGs was examined by normalization of the target gene, gonadotropin-releasing hormone (GnRH), in the hypothalamus. RESULTS: PPIA, HPRT1, and YWHAZ were the most stable RGs in the HPG axis-related tissues in sows regardless of the stages of estrus cycle. In contrast, traditional RGs, including 18S and ACTB, were found to be the least stable under these experimental conditions. In particular, in the normalization of GnRH expression in the hypothalamus against several stable RGs, PPIA, HPRT1, and YWHAZ, could generate significant (p<0.05) elevation of GnRH in the preovulatory phase compared to the luteal phase, but the traditional RGs with the least stability (18S and ACTB) did not show a significant difference between groups. CONCLUSION: These results indicate the importance of verifying RG stability prior to commencing research and may contribute to experimental design in the field of animal reproductive physiology as reference data.

19.
Life Sci ; 288: 120170, 2022 Jan 01.
Article in English | MEDLINE | ID: mdl-34826438

ABSTRACT

AIMS: Antitumor effects of veratramine in prostate and liver cancers has been investigated, but it is still unclear whether veratramine can be used as an effective therapeutic agent for glioma. The aim of this study was to evaluate the potential pharmacological mechanism of veratramine in glioma. MAIN METHODS: Using four types of human glioblastoma cell lines, including A172, HS-683, T98G, and U-373-MG the dose-dependent antitumor effect of veratramine was evaluated. The cytotoxicity and cell proliferation were examined by CCK-8, and cell proliferation was further confirmed by anchorage-independent colony formation assay. The cell cycle distribution and apoptotic rate was assessed by flow cytometry, and apoptosis was further evaluated by apoptosis assay. The migration and invasiveness capacity were analyzed by using transwell. Protein and mRNA levels of related factors were determined by western blotting and RT-qPCR, respectively. KEY FINDINGS: Veratramine markedly induced apoptosis, suppressed the cell proliferation via the cell cycle G0/G1 phase arrest, and reduced the capacity for the migration and invasion in human glioblastoma multiforme cell lines. Moreover, veratramine was sufficient to affect the phosphatidylinositol-3-kinase/serine-threonine kinase/mechanistic target of rapamycin signaling pathway and its downstream Mdm2/p53/p21 pathway in human glioblastoma cell lines. SIGNIFICANCE: Antitumor effects of veratramine in suppression of glioma progression was mediated by the regulation of PI3K/Akt/mTOR and Mdm2/p53/p21 signaling pathway.


Subject(s)
Gene Expression Regulation, Neoplastic/drug effects , Glioblastoma/drug therapy , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , TOR Serine-Threonine Kinases/metabolism , Veratrum Alkaloids/pharmacology , Apoptosis , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Cell Cycle , Cell Movement , Cell Proliferation , Cyclin-Dependent Kinase Inhibitor p21/genetics , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Glioblastoma/genetics , Glioblastoma/metabolism , Glioblastoma/pathology , Humans , Neoplasm Invasiveness , Phosphatidylinositol 3-Kinases/genetics , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-mdm2/genetics , Proto-Oncogene Proteins c-mdm2/metabolism , TOR Serine-Threonine Kinases/genetics , Tumor Cells, Cultured , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
20.
Animals (Basel) ; 12(21)2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36359090

ABSTRACT

The release of reproductive hormones in the hypothalamic-pituitary-gonadal (HPG) axis is regulated by its upstream regulator, kisspeptin, and influenced by external stresses, including heat stress. Since the effect of heat stress (summer infertility) on hypothalamic kisspeptin expression in domestic sows is not yet understood, the present study attempted to identify changes in kisspeptin expression in different seasons (summer and spring). The high atmospheric temperature in summer decreased the pregnancy rate and litter size and increased stress-related hormones as a chronic stressor to domestic sows. The hypothalamic kisspeptin expression in summer was decreased regardless of the estrus phase and negatively correlated with atmospheric temperature, indicating that high temperature decreased kisspeptin. When the activity of hypothalamic kisspeptin neurons in the follicular phase was assessed using c-Fos staining, a decreased number of kisspeptin neurons coexpressing c-Fos was observed in domestic sows in summer. Accordingly, lower expression of kisspeptin induced decreased levels of HPG axis-related reproductive hormones, such as gonadotropins and estrogen, and fewer large ovarian follicles. In conclusion, the present study demonstrated that reduced kisspeptin expression and its neuronal activity in the hypothalamus under heat stress in summer induced downregulation of the HPG axis and caused summer infertility in domestic sows.

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