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Improving porous properties of activated carbon from carbon gel by the OTA method. RSC Adv 2023; 13:14065-14077. [PMID: 37180012 PMCID: PMC10167907 DOI: 10.1039/d3ra01647a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 05/03/2023] [Indexed: 05/15/2023] Open
Abstract
High-surface-area microporous-mesoporous carbons were produced from carbon gel by applying the three consecutive steps of air oxidation, thermal treatment, and activation (the OTA method) to the gel. The formation of mesopores occurs both inside and outside the nanoparticles which form the carbon gel, while micropores are predominantly created within the nanoparticles. The OTA method offered a greater increase in pore volume and BET surface area of the resulting activated carbon in comparison with conventional CO2 activation either under the same activation conditions or at the same degree of carbon burn-off. Under the best preparation conditions, the maximum values of micropore volume, mesopore volume, and BET surface area achievable using the OTA method were found to be 1.19 cm3 g-1, 1.81 cm3 g-1, and 2920 m2 g-1, respectively at a 72% carbon burn-off. The larger increase in porous properties of activated carbon gel prepared by the OTA method over those based on conventional activation stems from the effects of the oxidation and heat treatment steps of the OTA method that could produce a large number of reaction sites which lead to efficient pore formation during the following CO2 activation process.
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2
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Pulmonary nocardiosis caused by Nocardia pneumoniae mimicking non-tuberculous mycobacterial disease. QJM 2022; 115:625-626. [PMID: 35587749 DOI: 10.1093/qjmed/hcac126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Indexed: 11/14/2022] Open
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3
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Enhancing the efficiency of gas-liquid-solid reactions using a monolithic microhoneycomb catalyst. Catal Today 2021. [DOI: 10.1016/j.cattod.2021.11.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Effect of Heat-Treatment Temperature of Carbon Gels on Cathode Performance of Lithium-Air Batteries. JOURNAL OF CHEMICAL ENGINEERING OF JAPAN 2021. [DOI: 10.1252/jcej.20we095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Development of an efficient CVD technique to prepare TiO 2/porous-carbon nanocomposites for high rate lithium-ion capacitors. RSC Adv 2020; 10:38196-38204. [PMID: 35517514 PMCID: PMC9057307 DOI: 10.1039/d0ra07590f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 10/09/2020] [Indexed: 11/21/2022] Open
Abstract
Titanium dioxide is a promising electrode material for lithium-ion capacitors. When using TiO2 as an electrode material, it is necessary to combine it with carbon at the nanometer level to improve its low electrical conductivity and low reactivity with Li+. However, preparation methods of reported TiO2/porous–carbon nanocomposites are generally not cost-effective, and their productivities are low. In this study, the vacuum liquid-pulse chemical vapor deposition (VLP-CVD) technique was developed to easily prepare TiO2/porous–carbon nanocomposites, where TiO2 nanoparticles with a diameter of ∼4 nm could be homogeneously deposited inside the pores of meso- or macroporous carbons. Because the deposited TiO2 nanoparticles had access to effective electrically conductive paths formed by the porous–carbon substrate, they showed a high discharge capacity of ∼200 mA h g−1-TiO2 (based on TiO2 weight). In particular, the composite prepared from macroporous carbon showed an extremely high rate performance, where 50% of the discharge capacity was retained at a current density of 15 000 mA g−1 when compared to that measured at 50 mA g−1. In addition, the composite also showed very high cyclability, where 80% of the discharge capacity was retained at the 10 000th cycle. Because the VLP-CVD technique can be performed using simple apparatus and commercially available starting materials, it can be expected to boost industrial production of TiO2/porous–carbon for lithium-ion capacitors. TiO2 nanoparticles with a diameter of around 5 nm were homogeneously deposited inside the pores of meso-macroporous carbons.![]()
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OR11: The Impact of Pretransplant Sarcopenia and Perioperative Rehabilitation with Nutritional Therapy on Outcomes After Living Donor Liver Transplantation: A Prospective Study. Clin Nutr 2019. [DOI: 10.1016/s0261-5614(19)32483-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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7
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Catalytic Activity for Oxygen Reduction Reaction of Ni-Mn-Fe Layered Double Hydroxide-Carbon Gel Composite. CHEM LETT 2019. [DOI: 10.1246/cl.190036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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8
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Cost-effective synthesis of activated carbons with high surface areas for electrodes of non-aqueous electric double layer capacitors. Sep Purif Technol 2019. [DOI: 10.1016/j.seppur.2018.04.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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9
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Development of TiO 2-SiO 2 Photocatalysts Having a Microhoneycomb Structure by the Ice Templating Method. ACS OMEGA 2018; 3:14274-14279. [PMID: 31458118 PMCID: PMC6644808 DOI: 10.1021/acsomega.8b01880] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 10/18/2018] [Indexed: 06/10/2023]
Abstract
Immobilization of TiO2-based photocatalysts usually suffers from lowered surface area and mass transfer limitation compared with their suspended counterpart. In this work, TiO2-SiO2 monolithic photocatalysts having straight macropores, called microhoneycombs, were synthesized. The obtained samples had straight macropores with a diameter in the range of 15-40 μm formed by walls having a thickness up to 5 μm. The samples also contain micropores and small mesopores inside their walls, which contribute to high surface areas of more than 500 m2 g-1. Synthesized photocatalysts were tested in a continuous flow system using the decolorization of methylene blue as a model reaction. It was found that the unique morphology of the samples can be used to promote the uniform distribution of the target fluid while reducing the pressure drop across the photocatalyst to less than a hundredth compared with a packed bed system. In addition, calcination at 600-800 °C improved the strength and photocatalytic activity of the monoliths while preserving the high surface area of the samples.
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Carbon Paper with a High Surface Area Prepared from Carbon Nanofibers Obtained through the Liquid Pulse Injection Technique. ACS OMEGA 2018; 3:691-697. [PMID: 31457924 PMCID: PMC6641430 DOI: 10.1021/acsomega.7b01822] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 01/11/2018] [Indexed: 06/10/2023]
Abstract
To improve the performance of carbon paper used for applications such as electrodes for electrochemical devices and air filters, two types of long carbon nanofibers (CNFs) with average diameters of 20 and 49 nm were prepared by the liquid pulse injection (LPI) technique by adjusting reaction conditions. Carbon paper was made from the CNFs through a simple filtration process. The paper prepared from the CNFs with an average diameter of 20 nm (LPI-CNF(20) paper) was firm and flexible even though it was prepared without using any binders. LPI-CNF(20) paper also had a high surface area and showed a high electrical conductivity and a moderate gas permeability according to its void size. These properties are required for cathodes in the latest battery systems such as lithium-air batteries. In electrochemical experiments conducted to evaluate the performance of LPI-CNF(20) paper as a cathode, the paper showed a larger discharge capacity on the basis of the cathode weight than a conventional cathode (a commercially available carbon paper combined with a porous carbon), which indicated that it has a high potential to be used as a cathode in lithium-air batteries.
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11
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CO 2 Separation in a Flow System by Silica Microhoneycombs Loaded with an Ionic Liquid Prepared by the Ice-Templating Method. Ind Eng Chem Res 2017. [DOI: 10.1021/acs.iecr.6b05001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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12
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PMMA-Templated Carbon Gel Monoliths with Independently Tunable Micro-, Meso-, and Macropores. JOURNAL OF CHEMICAL ENGINEERING OF JAPAN 2017. [DOI: 10.1252/jcej.16we313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Cellulose Nanofiber as a Distinct Structure-Directing Agent for Xylem-like Microhoneycomb Monoliths by Unidirectional Freeze-Drying. ACS NANO 2016; 10:10689-10697. [PMID: 27809476 DOI: 10.1021/acsnano.6b05808] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Honeycomb structures have been attracting attention from researchers mainly for their high strength-to-weight ratio. As one type of structure, honeycomb monoliths having microscopically dimensioned channels have recently gained many achievements since their emergence. Inspired by the microhoneycomb structure that occurs in natural tree xylems, we have been focusing on the assembly of such a structure by using the major component in tree xylem, cellulose, as the starting material. Through the path that finally led us to the successful reconstruction of tree xylems by the unidirectional freeze-drying (UDF) approach, we verified the function of cellulose nanofibers, toward forming xylem-like monoliths (XMs). The strong tendency of cellulose nanofibers to form XMs through the UDF approach was extensively confirmed with surface grafting or a combination of a variety of second components (or even a third component). The resulting composite XMs were thus imparted with extra properties, which extends the versatility of this kind of material. Particularly, we demonstrated in this paper that XMs containing reduced graphene oxide (denoted as XM/rGO) could be used as strain sensors, taking advantage of their penetrating microchannels and the bulk elasticity property. Our methodology is flexible in its processing and could be utilized to prepare various functional composite XMs.
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Li-rich Li-Si alloy as a lithium-containing negative electrode material towards high energy lithium-ion batteries. Sci Rep 2015; 5:8085. [PMID: 25626879 PMCID: PMC4308695 DOI: 10.1038/srep08085] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 01/06/2015] [Indexed: 11/23/2022] Open
Abstract
Lithium-ion batteries (LIBs) are generally constructed by lithium-including positive electrode materials, such as LiCoO2, and lithium-free negative electrode materials, such as graphite. Recently, lithium-free positive electrode materials, such as sulfur, are gathering great attention from their very high capacities, thereby significantly increasing the energy density of LIBs. Though the lithium-free materials need to be combined with lithium-containing negative electrode materials, the latter has not been well developed yet. In this work, the feasibility of Li-rich Li-Si alloy is examined as a lithium-containing negative electrode material. Li-rich Li-Si alloy is prepared by the melt-solidification of Li and Si metals with the composition of Li21Si5. By repeating delithiation/lithiation cycles, Li-Si particles turn into porous structure, whereas the original particle size remains unchanged. Since Li-Si is free from severe constriction/expansion upon delithiation/lithiation, it shows much better cyclability than Si. The feasibility of the Li-Si alloy is further examined by constructing a full-cell together with a lithium-free positive electrode. Though Li-Si alloy is too active to be mixed with binder polymers, the coating with carbon-black powder by physical mixing is found to prevent the undesirable reactions of Li-Si alloy with binder polymers, and thus enables the construction of a more practical electrochemical cell.
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Conversion of silica nanoparticles into Si nanocrystals through electrochemical reduction. NANOSCALE 2014; 6:10574-10583. [PMID: 24969702 DOI: 10.1039/c4nr01687d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The precise design of Si-based materials at the nanometer scale is a quite complex issue but of utmost importance for their present and potential applications. This paper reports the first attempt to address the electrochemical reduction of SiO₂ at the nanometer scale. SiO₂ nanoparticles are first covered with a uniform carbon layer with controlled thickness at an accuracy of a few nanometers, by pressure-pulsed chemical vapor deposition. With appropriate thickness, the carbon layer plays significant roles as a current path and also as a physical barrier against Si-crystal growth, and the SiO₂ nanoparticles are successfully converted into extremely small Si nanocrystals (<20 nm) inside the shell-like carbon layer whose morphology is derived from the original SiO₂ nanoparticles. Thus, the proposed electroreduction method offers a new synthesis strategy of Si-C nanocomposites utilizing the morphology of SiO₂ nanomaterials, which are well known for a wide variety of defined and regular nanostructures. Owing to the volume difference of SiO₂ and the corresponding Si, nanopores are generated around the Si nanocrystals. It has been demonstrated that the nanopores around the Si nanocrystals are effective to improve cycle performance of Si as a negative electrode for lithium-ion batteries. The present method is in principle applicable to various SiO₂ nanomaterials, and thus, offers production of a variety of Si-C composites whose carbon nanostructures can be defined by their parent SiO₂ nanomaterials.
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Synthesis of silica-based porous monoliths with straight nanochannels using an ice-rod nanoarray as a template. ACTA ACUST UNITED AC 2008. [DOI: 10.1039/b806005c] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gastric carcinosarcoma with neuroendocrine differentiation as the carcinoma component and leiomyosarcomatous and myofibroblastic differentiation as the sarcomatous component. APMIS 2006; 114:234-8. [PMID: 16643190 DOI: 10.1111/j.1600-0463.2006.apm_328.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Gastric carcinosarcoma with neuroendocrine differentiation is a very rare neoplasm. In this article we present such a case. The gastroendoscopic examination of a 59-year-old Japanese man disclosed gastric cancer during follow-up after operation for rectal cancer. Subsequently, total gastrectomy was carried out because of gastric cancer. A large tumor measuring 9.2 x 8.4 cm was observed in the posterior wall of the upper portion of the stomach. The tumor was composed of carcinoma and sarcomatous cells, and the histological transition of both components was observed. Immunohistochemically, carcinoma and sarcomatous cells were positive for cytokeratin CAM5.2. The carcinoma contained adenocarcinoma and malignant cells with neuroendocrine differentiation. The sarcomatous component showed leiomyosarcomatous and myofibroblastic differentiation. The present tumor is the fifth case of gastric carcinosarcoma with neuroendocrine differentiation and the first case of gastric carcinosarcoma with myofibroblastic differentiation. Pathologists should bear in mind that gastric carcinosarcoma may show various types of differentiation.
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285BIRTH OF PIGLETS AFTER NON-SURGICAL TRANSFER OF PORCINE EMBRYOS
CULTURED IN PZM-4 WITH ALTERED CONCENTRATIONS OF AMINO ACIDS. Reprod Fertil Dev 2004. [DOI: 10.1071/rdv16n1ab285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
We previously developed an in vitro production (IVP) system for porcine embryos and obtained piglets after surgical transfer of blastocysts cultured in Porcine Zygote Medium (PZM)-4. However, the developmental competence of pig IVP embryos to the blastocyst stage is still low and further improvement of IVC medium is needed. In the present study, we evaluated the effects of the addition of glutamine (Gln), hypotaurine (HT), taurine (Tau), BME-essential (EA) and MEM-nonessential (NA) amino acids solutions to PZM-4, and the replacement of polyvinyl alcohol (PVA) with BSA on embryo development to blastocysts. Moreover, the developmental competence of IVP blastocysts after nonsurgical embryo transfer (NS-ET), using a flexible catheter (FC) for deep intrauterine insemination, was investigated. Porcine COC from prepubertal gilts were matured and fertilized in vitro, using frozen-thawed ejaculated boar semen. Presumptive zygotes were cultured in PZM-4, as a basal culture medium, until Day 5 after IVF. Data from six replicates were analyzed by ANOVA. Addition of 0.25 to 4mM Gln to PZM-4 (containing 5mM HT) significantly increased the percentage of embryos that developed to blastocysts (15 to 31%), with addition of 2mM Gln significantly increasing the total cell numbers in blastocysts (43±17 cells) compared with no addition (3% and 20±4 cells, respectively). Addition of 1.25 to 10mM HT to HT-free PZM-4 supplemented with 2mM Gln (named PZM-5) significantly increased the percentage of embryos that developed to blastocysts (22 to 28%) compared with control (no HT;; 4%). In the culture with HT-free PZM-5, addition of 5mM Tau significantly increased blastocyst yield (17%) compared with control (4%). However, Tau addition in the presence of 5mM HT had no effect on development to the blastocyst stage. In combinations of EA and NA added to PZM-5, a single dose of EA significantly increased the percentage of embryos that developed to blastocysts (27%) compared with no dose (19%) or with a double dose of EA (20%), while a double dose of NA significantly increased the total cell numbers in blastocysts (43±16 cells) compared with no NA (37± 6 cells). Replacement of PVA with BSA in PZM-5 had no effect on embryo development to the blastocyst stage. Crossbred sows were used as recipients for NS-ET, and had their estrous cycle synchronized by a described previously method (Yoshioka et al., 2002 Biol. Reprod. 66, 112–119). Five days after hCG injection, a FC was introduced via the cervix into the uterine horn of recipients without sedation. Day-5 blastocysts cultured in PZM-5 were then transferred together with 5ml of TALP-Hepes (45 to 50 blastocysts/recipient). Of 6 recipients, one sow became pregnant and farrowed 7 piglets. Our results indicate that the addition of amino acids to PZM-4 can improve porcine embryo development to the blastocyst stage, and that blastocysts cultured in a chemically defined medium, PZM-5, can develop to full-term following NS-ET.
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Validation of an analytical method for a potent antitumor agent, TZT-1027, in plasma using liquid chromatography-mass spectrometry. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 762:155-63. [PMID: 11678375 DOI: 10.1016/s0378-4347(01)00360-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A sensitive and specific analytical method for a potent antitumor agent, TZT-1027, in plasma has been developed using liquid chromatography-mass spectrometry (LC-MS) with [2H4]TZT-1027 as an internal standard (I.S.). A plasma sample was purified by solid-phase extraction on a C18 cartridge, followed by solvent extraction with diethyl ether. The extract was then injected into the LC-MS system. Chromatography was carried out on a C18 reversed-phase column using acetonitrile-0.05% trifluoroacetic acid (TFA) (55:45) as a mobile phase. Mass spectrometric analysis was performed in atmospheric pressure chemical ionization (APCI) mode with positive ion detection, and the protonated molecular ions ([M+H]+) of TZT-1027 and I.S. were monitored to allow quantitation. The method was applied to the determination of TZT-1027 in human, monkey, dog, rat and mouse plasma. As far as the sample preparation was concerned, good recoveries (73.5-99.1%) were obtained. The calibration curves were linear over the range of 0.25-100 ng per 1 ml of human, dog and rat plasma, per 0.5 ml of monkey plasma, and per 0.1 ml of mouse plasma. From the intra- and inter-day accuracy and precision, the present method satisfies the accepted criteria for bioanalytical method validation. TZT-1027 was stable when stored below -15 degrees C for 6 months in human plasma and for 3 weeks in plasma from other species. TZT-1027 was also stable in plasma through at least three freeze-thaw cycles.
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Cytochrome P450 enzymes involved in the metabolic pathway of the histamine 2 (H2)-receptor antagonist roxatidine acetate by human liver microsomes. ARZNEIMITTEL-FORSCHUNG 2001; 51:651-8. [PMID: 11556126 DOI: 10.1055/s-0031-1300096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Roxatidine acetate hydrochloride (ROX, 2-acetoxy-N-[3-[m-(1-piperidinylmethyl)phenoxy]propyl]acetamide hydrochloride, CAS 78273-80-0), a histamine 2 (H2)-receptor antagonist, has been clinically applied for the treatment of gastritis, gastric and duodenal ulcers. There is no report on the identification of the metabolic enzyme of M-1 (2-hydroxy-N-[3-[m-(1-piperidinylmethyl)phenoxy]propyl]acetamide), the pharmacologically active metabolite, in humans. In this study, the Cytochrome P450 (CYP or P450) enzymes which participate in the metabolism of ROX were identified using human liver microsomes and S9 fractions. M-1 was converted to M-4 (3-[m-(1-piperidinyl-methyl)phenoxy]propylamine) by the enzyme reaction with the S9 but not with microsomes. M-4 was further metabolized to M-5 (3-[m-(1-piperidinylmethyl)phenoxy]propanol) by microsomes. The metabolism was inhibited by coumarin and anti-CYP2A1 serum. (3-[m-(1-piperidinylmethyl)-phenoxy]propionic acid) and M-3 (m-(1-piperidinylmethyl) phenol) formation from M-5 were inhibited by quinidine and anti-CYP2D6 serum. Moreover, M-5 was converted to M-2 and M-3 by cDNA-expressed CYP2D6. In conclusion, this study shows that microsomal enzymes do not participate in the clearance of the active metabolite M-1, CYP2A6 primarily catalyzes M-5 formation from M-4, and CYP2D6 primarily catalyzes M-2 and M-3 formation from M-5 in humans.
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Endotoxin induces delayed ovulation following endocrine aberration during the proestrous phase in Holstein heifers. Domest Anim Endocrinol 2001; 20:267-78. [PMID: 11518620 DOI: 10.1016/s0739-7240(01)00098-4] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The effect of endotoxin on follicular growth and on secretion of LH, estradiol-17beta, progesterone and cortisol during the proestrous phase in cattle was investigated. Holstein heifers were treated with PGF2alpha at 11-13 d after ovulation to induce luteolysis. At 42 hr after PGF2alpha treatment, heifers were administered either lipopolysaccharide (LPS; Escherichia coli, O111:B4, 5 microg/kg, n = 6) or saline (control; n = 6) by i.v. bolus injection. Ovarian structures were monitored daily by transrectal ultrasonography, and blood samples were collected at various times for hormonal analysis. The duration from PGF2alpha treatment to ovulation was significantly longer in the LPS group (8.0 +/- 1.3 d) than in the control group (4.2 +/- 0.2 d). LPS significantly reduced the pulse frequency of LH for 6 hr after the administration, and increased the mean concentration and pulse amplitude of LH from 3 to 6 hr after the administration. The plasma concentrations of progesterone and cortisol were transiently increased after LPS administration. The plasma concentration of estradiol-17beta was significantly decreased at 24 hr after LPS administration compared to that in the controls. Five of six LPS-treated heifers exhibited no preovulatory LH surge until 120 hr after PGF2alpha treatment and the remaining heifer exhibited the surge at 108 hr after PGF2alpha treatment, while the LH surge was observed at 54-78 hr after PGF2alpha treatment in control heifers. These results suggest that endotoxin disrupts progression of the proestrous phase of cattle, interrupting the preovulatory estradiol rise and thus delaying the LH surge and the subsequent ovulation.
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Gonadotropin-releasing hormone in third ventricular cerebrospinal fluid of the heifer during the estrous cycle. Biol Reprod 2001; 64:563-70. [PMID: 11159359 DOI: 10.1095/biolreprod64.2.563] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The release profile of GnRH in cerebrospinal fluid (CSF) and its correlation with LH in peripheral blood of ovary-intact heifers during the estrous cycle were investigated. A silicon catheter was placed into the third ventricle of six heifers using ultrasonography. During the mid-luteal phase, the heifers were injected with prostaglandin F(2alpha) to induce luteolysis. Surges of CSF GnRH (66.7 h after prostaglandin F(2alpha) administration) and peripheral LH (66.3 h) occurred simultaneously and were coincident with the onset of estrus (67.0 h). Duration of elevated GnRH concentration considerably overlapped with the estrous phase in each of the heifers. Mean pulse frequencies of both GnRH and LH were significantly higher during the proestrous and early luteal phases than during the mid-luteal phase, while mean concentration and pulse amplitude of both GnRH and LH were not different between these three phases. Of all the GnRH pulses identified, more than 80% were accompanied by an LH pulse during the proestrous and early luteal phases. However, the proportion of GnRH pulses that were coincident with an LH pulse during the mid-luteal phase decreased to 60%. The results clearly demonstrate that a dynamic (pulse) and longer-term (surge) changes of GnRH release into CSF are physiologically expressed during the estrous cycle in heifers, and the pattern of pulsatile GnRH secretion in heifers depends upon their estrous cycle.
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Effects of activin A and follistatin on developmental kinetics of bovine embryos: cinematographic analysis in a chemically defined medium. Reproduction 2000. [DOI: 10.1530/reprod/118.1.119] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The effects of recombinant human activin A and follistatin on the developmental kinetics of bovine presumptive zygotes matured and fertilized in vitro using time-lapse cinematography were investigated. The presumptive zygotes were cultured for 9 days in a chemically defined medium (modified synthetic oviduct fluid, control) and modified synthetic oviduct fluid supplemented with activin A or follistatin. Development under cine-recording conditions was similar to that in an incubator. Addition of activin A to modified synthetic oviduct fluid increased, while addition of follistatin decreased, the percentage of zygotes that developed to morulae and blastocysts. Follistatin significantly prolonged the timing of development to the 9-16-cell stage compared with the control and activin A media. Activin A significantly shortened the duration of the third cell cycle compared with the control, but follistatin significantly prolonged the fourth cell cycle compared with the control and activin A. Developmental arrest ('lag-phase') during the 4-8-cell stage was observed in 95% of embryos developed to more than the 9-16-cell stage in all treatments. The greater the number of cells at the onset of the lag-phase, the earlier the onset of the phase and the shorter the duration of the phase, the further embryos were able to develop by day 9 in all treatments. The number of cells at the onset of the lag-phase in the medium containing activin A was significantly higher than it was in control or follistatin-containing media. Moreover, activin A significantly shortened the duration of the lag-phase compared with follistatin. The present results indicate that activin A may enhance in vitro development of bovine embryos by improving developmental kinetics, especially by increasing the number of cells at the onset of the lag-phase and shortening the duration of this phase.
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Effects of activin A and follistatin on developmental kinetics of bovine embryos: cinematographic analysis in a chemically defined medium. JOURNAL OF REPRODUCTION AND FERTILITY 2000; 118:119-25. [PMID: 10793633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The effects of recombinant human activin A and follistatin on the developmental kinetics of bovine presumptive zygotes matured and fertilized in vitro using time-lapse cinematography were investigated. The presumptive zygotes were cultured for 9 days in a chemically defined medium (modified synthetic oviduct fluid, control) and modified synthetic oviduct fluid supplemented with activin A or follistatin. Development under cine-recording conditions was similar to that in an incubator. Addition of activin A to modified synthetic oviduct fluid increased, while addition of follistatin decreased, the percentage of zygotes that developed to morulae and blastocysts. Follistatin significantly prolonged the timing of development to the 9-16-cell stage compared with the control and activin A media. Activin A significantly shortened the duration of the third cell cycle compared with the control, but follistatin significantly prolonged the fourth cell cycle compared with the control and activin A. Developmental arrest ('lag-phase') during the 4-8-cell stage was observed in 95% of embryos developed to more than the 9-16-cell stage in all treatments. The greater the number of cells at the onset of the lag-phase, the earlier the onset of the phase and the shorter the duration of the phase, the further embryos were able to develop by day 9 in all treatments. The number of cells at the onset of the lag-phase in the medium containing activin A was significantly higher than it was in control or follistatin-containing media. Moreover, activin A significantly shortened the duration of the lag-phase compared with follistatin. The present results indicate that activin A may enhance in vitro development of bovine embryos by improving developmental kinetics, especially by increasing the number of cells at the onset of the lag-phase and shortening the duration of this phase.
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Effects of activin A and follistatin on developmental kinetics of bovine embryos: cinematographic analysis in a chemically defined medium. Reproduction 2000. [DOI: 10.1530/jrf.0.1180119] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Characterizations of mouse hepatic microsomal monooxygenase catalyzing 11beta-hydroxylation of osaterone acetate. Biochem Pharmacol 1999; 58:335-41. [PMID: 10423176 DOI: 10.1016/s0006-2952(99)00098-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Osaterone acetate (17alpha-acetoxy-6-chloro-2-oxa-4,6-pregnadiene-3,20-dione, OA) is a new steroidal antiandrogen. There is a marked species difference in the metabolism of OA in that 11beta-hydroxylated metabolites are found in the plasma, feces, and urine of mice after oral administration of OA, but there is very little metabolism in rats and humans. OA reduces the adrenal gland weight in mice, but not in rats, and this effect in mice might be explained by the species difference in 11beta-hydroxylation activity. The objectives of this study were to elucidate the enzyme(s) involved in this particular oxidation and to explain the species difference observed. Mouse hepatic microsomes oxidize OA to 11beta-OH OA, and this oxidation requires NADPH as a cofactor. The use of various competitive and allosteric inhibitors of cytochrome P450 and flavin-containing monooxygenase (i.e. CO, N-octylamine, and methimazole) showed that the oxidation of OA was catalyzed by cytochrome P450. In microsomes from mice pretreated with phenobarbital (a CYP2B-selective inducer), 3-methylcholanthrene (a CYP1A-selective inducer), pregnenolone-16alpha-carbonitrile (a CYP3A-selective inducer), and EtOH (a CYP2E-selective inducer), an increase in the rates of oxidation was seen only in microsomes from EtOH-treated animals. However, metyrapone, a selective inhibitor for enzymes of the cytochrome P45011B and P4502B family, inhibited mouse hepatic microsomal 11beta-hydroxylation by < 30%. The results obtained showed that the production of 11beta-OH OA may be catalyzed by a novel cytochrome P450 in mouse liver.
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Abstract
It has been reported that there were no significant changes in the recurrent laryngeal nerves of patients with adductor spasmodic dysphonia, which could explain the cause of this disease. However, the researchers who made these reports appeared to have investigated only the extralaryngeal part of the nerve involved in the neck. Because the recurrent laryngeal nerve contains many components that distribute to various organs, we must study in greater detail a more peripheral part of the motor nerve, which has a much closer relationship to vocal cord movements. At the time of surgery we obtained specimens of the thyroarytenoid branches of the recurrent laryngeal nerves in two female patients with adductor spasmodic dysphonia. Although histologic analysis revealed no apparent signs of either destruction or degeneration, the percentage of thin nerve fibers, the diameter of which may range from 5 to 10 microm, was higher than in normal controls. This suggests the possibility of a neurologic abnormality in the larynges of ASD patients.
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Abstract
A total of 29 SPF Large White prepuberal gilts (mean age 152 days at treatment) were examined for estrous and ovulatory responses after PG 600 treatment. After treatment, 85.2% of the gilts showed standing estrus within 6 days. Whereas the treatment-to-estrus interval and duration were 3.7 and 1.9 days respectively. As ovulation occurred on Day 5 to 6, appropriate timing of artificial insemination would be about 4 days after treatment. Fertility of gilts revealed to be excellent, giving rise to a high percentage of normal embryos, 85.3%. Meanwhile, development and growth of fetuses were mostly normal. Other reproductive performances recorded were: mean litter size 6.8; mean birth weight 1.26 kg; weaning-to-return estrus interval 5 to 8 days. In conclusion, PG 600 was found to be useful in inducing fertile estrus in prepuberal gilts, a result which will be of interest for commercial pig farms.
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Activin A and follistatin regulate developmental competence of In vitro-produced bovine embryos. Biol Reprod 1998; 59:1017-22. [PMID: 9780304 DOI: 10.1095/biolreprod59.5.1017] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The effects of activin A and/or follistatin on the development of bovine embryos were investigated. Presumptive zygotes matured and fertilized in vitro were cultured in a chemically defined medium (modified synthetic oviduct fluid medium; mSOF). Addition of 1-100 ng/ml of activin A to mSOF significantly increased the percentage of zygotes that developed to morulae and blastocysts (48-54% and 31-41%, respectively) compared with no addition (41% and 25%, respectively). In contrast, addition of 1-100 ng/ml follistatin significantly reduced the percentage of zygotes developing to morulae and blastocysts (29-31% and 17-20%, respectively) compared with no addition (41% and 28%, respectively). In a culture with 10 ng/ml of activin A, supplementation with the same concentration of follistatin neutralized the positive effect of activin A, while supplementation with 100 ng/ml of follistatin reduced the percentage of zygotes that developed. The total cell numbers in morulae and blastocysts were not affected by the addition of activin A and/or follistatin. The development-enhancing effects of activin A and the development-impeding effects of follistatin were observed when embryos were exposed to activin A or follistatin at a concentration of 10 ng/ml prior to the 9- to 16-cell stage. These results suggest that activin A and follistatin may affect bovine embryos until the third cell cycle and may play important roles in regulation of the developmental competence of bovine embryos.
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Changes of ovarian structures, plasma LH, FSH, progesterone and estradiol-17 beta in a cow with ovarian cysts showing spontaneous recovery and relapse. J Vet Med Sci 1998; 60:257-60. [PMID: 9524954 DOI: 10.1292/jvms.60.257] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In a cow diagnosed as having ovarian cysts, we observed changes in the ovarian structures by ultrasonography for 71 days and examined plasma concentrations of sex hormones. The cow had 2 regressing cysts at the start of this study and 3 new follicles subsequently developed into cysts. With regression of these cysts, 2 new follicles developed and ovulated spontaneously, followed by the formation of 2 corpora lutea. On the day prior to ovulation, a preovulatory luteinizing hormone (LH) surge was detected. With regression of the corpora lutea, a new follicle developed and underwent atresia. Meantime, another follicle developed and became a cyst without ovulation. No preovulatory LH surge was observed during the period from regression of the corpora lutea to cyst formation. The results indicate that absence of the preovulatory LH surge is associated with occurrence of ovarian cysts and this endocrine aberration is reversible.
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Differential responses to ligands of overexpressed thyroid hormone and retinoid X receptors in a Xenopus cell line and in vivo. Mol Cell Endocrinol 1997; 126:17-24. [PMID: 9027359 DOI: 10.1016/s0303-7207(96)03965-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In an attempt to explain the contrasting patterns of expression of Xenopus thyroid hormone (xTR) and retinoid X (xRXR) receptor genes and to extend our understanding of the role of heterodimerization of these receptors during amphibian metamorphosis, we have investigated the response to their respective ligands of cells in which xTR and xRXR were overexpressed. Results obtained with two separate approaches are now described. In the first, 3,3'5-triiodothyronine (t3) was found to strongly upregulate xTR beta mRNA in XTC-2 cells, but not of xTR alpha or xRXR alpha mRNAs, while xRXR gamma transcripts could not be detected. 9-cis-retinoic acid (9-cis-RA) did not substantially influence the expression of any of these four receptor genes. When transcription from three different thyroid response elements (TREs) (a palindromic TREpal, an inverted repeat +6 [F2] and a direct repeat +4[DR+4] as present in the promoter of xTR beta gene) was measured in XTC-2 cells in which xTR beta and xRXR alpha were overexpressed, only T3 upregulated transcription while 9-cis-RA, alone or together with T3, was ineffective. 9-cis-RA however enhanced transcription from an RXR responsive element (RXR-RE). THe second approach involved overexpression of xTR beta and xRXR alpha in premetamorphic Xenopus tadpole tail muscle followed by measuring the response of the tails to T3 in organ culture. After validating the microinjection/culture procedure histochemically, we found that T3 enhanced transcription from the xTR beta DR +4 TRE in tails in which xTR beta was overexpressed but the overexpression of xRXR alpha failed to modify this response. It is concluded that in both XTC cells and tadpole tails, overexpressed xRXR fails to modify the enhanced transcriptional response of endogenous and overexpressed xTR beta to T3 and that exogenous 9-cis-RA is ineffective.
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Ultrasonic observations on the turnover of ovarian follicular cysts and associated changes of plasma LH, FSH, progesterone and oestradiol-17 beta in cows. Res Vet Sci 1996; 61:240-4. [PMID: 8938855 DOI: 10.1016/s0034-5288(96)90071-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Changes in the diameters of individual follicular structures on ovaries were measured by transrectal ultrasonography for 29 to 40 days and the plasma concentrations of luteinising hormone (LH) follicle-stimulating hormone (FSH), progesterone and oestradiol-17 beta were determined in four cows with ovarian cysts. When these structures decreased in size, new follicular structures appeared and developed into cysts. Progesterone concentrations in plasma were below 1.0 ng ml-1 during the experimental periods. Plasma concentrations of oestradiol-17 beta fluctuated. The mean concentration of oestradiol-17 beta in plasma differed (P < 0.01) depending on the stage of the cyst. No preovulatory surges of LH were detected during the developmental stage of the cysts.
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Hepatic sinusoidal endothelial cells can store and metabolize serum immunoglobulin. Hepatology 1995; 22:1456-61. [PMID: 7590663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
Abstract
Sinusoidal inclusion-containing endothelial cells in the liver were investigated with particular interest in their capacity of metabolizing immunoglobulin. Formalin-fixed deparaffinized liver specimens were used for immunohistochemistry, and pronase digestion was proved to be effective for antigen retrieval of immunoglobulin. The inclusions in sinusoidal endothelial cells were strongly immunostained with anti-immunoglobulin (Ig)G, IgA, and IgM antibodies in predigested sections. The complements were not identified immunohistochemically in the inclusions even after pronase treatment. Two women with autoimmune liver disease, who initially represented high levels of serum gamma globulin and abundant inclusion-containing endothelial cells, were studied. The subsequent biopsy after effective corticosteroid therapy demonstrated significant histological improvement as well as the disappearance of inclusion-containing endothelial cells (ICECs). During and after treatment, their serum gamma globulin levels were drastically reduced. In conclusion, the hepatic sinusoidal endothelial cells can take up serum immunoglobulin, probably through a receptor-mediated pathway, and its excessive storage results in the formation of cytoplasmic inclusions that are easily recognized by a light microscope. The stored immunoglobulin may be degraded in the cytoplasm, and the inclusions would disappear in association with the reduction of sinusoidal gamma globulin content. In other words, the intralobular density of inclusion-containing endothelial cells is a morphological predictor for the serum gamma globulin level.
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Application of anti-bovine CD2 monoclonal antibody to the rosette inhibition test for detection of early pregnancy factor in cattle. J Vet Med Sci 1995; 57:721-5. [PMID: 8519905 DOI: 10.1292/jvms.57.721] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
To reliably detect early pregnancy factor (EPF) in cattle, monoclonal antibody specific for bovine CD2 molecule, which is the sheep red blood cell (SRBC) receptor on bovine T cell surface, was applied to the rosette inhibition test. The rosette inhibition titers (RITs) were significantly higher in pooled sera from early pregnant cattle than in those of non-pregnant cattle using two anti-bovine CD2 monoclonal antibodies, B26A4 (P < 0.001) and BAQ95A (P < 0.01). The dissociation value of RITs between pregnancy and non-pregnancy with B26A4 was greater than that with BAQ95A. The B26A4 monoclonal antibody was therefore applied to the rosette inhibition test in subsequent experiments. The RITs in serum of individual pregnant and non-pregnant cows 8 days after estrus were significantly different (P < 0.001) by three or more dilutions. When the rosette inhibition test was carried out in sera from individual pregnant and non-pregnant cows at estrus and at 24, 72 and 168 hr after ovulation, the RITs of pregnancy sera increased significantly at 24 hr after ovulation as compared with non-pregnancy sera (P < 0.001). These results indicate anti-bovine CD2 monoclonal antibody can be utilized with the rosette inhibition test to detect EPF in cattle, and that this assay detects bovine EPF for pregnancy serum at least 24 hr after ovulation.
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Exacerbation of primary biliary cirrhosis during interferon-alpha 2b therapy for chronic active hepatitis C. Dig Dis Sci 1995; 40:1226-30. [PMID: 7781437 DOI: 10.1007/bf02065528] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A 60-year-old woman with chronic active hepatitis C was treated with 6 million units of rIFN-alpha 2b daily for two weeks and subsequently three times weekly for several months. Histological examination proved a severe form of chronic active hepatitis C unexpectedly complicated with primary biliary cirrhosis (PBC). Before treatment, levels of serum alkaline phosphatase (ALP) or gammaglutamyltranspeptidase (GGT) had remained within normal limits over six months, although anti-mitochondrial antibody (AMA) was shown to be positive. After eight weeks of therapy, the daily dose of rIFN was reduced to 3 million units because of a marked increase of ALP and GGT, although the serum alanine aminotransferase (ALT) was normalized. Four months later, IFN treatment was suspended because of continuous elevation of the ALP and GGT levels, and administration of ursodeoxycholic acid was substituted. Two months later, the ALP and GGT levels returned to the normal range, although ALT was not normalized and HCV-RNA remained positive. This is the first report case that demonstrates IFN treatment potentially exacerbates PBC associated with chronic active hepatitis C. It is important for treating physicians to keep this association in mind.
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Sequential changes in human Ito cells and their relation to postnecrotic liver fibrosis in massive and submassive hepatic necrosis. Virchows Arch 1995; 426:95-101. [PMID: 7704328 DOI: 10.1007/bf00194703] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To examine the relationship of Ito cells to postnecrotic liver fibrosis, liver specimens, obtained at autopsy from 17 patients with acute massive necrosis (AMN) and acute submassive hepatic necrosis (ASMN), were examined immunohistochemically. In normal adult livers, Ito cells positive for alpha-smooth muscle actin isoform (ASMA) were rarely seen, scattered along hepatic sinusoids. In contrast, in AMN the Ito cells in necrotic areas became strongly positive for ASMA. They were swollen with elongated cytoplasmic processes along collapsed sinusoidal walls. Around these ASMA-positive Ito cells, there were numerous infiltrated macrophages and lymphocytes present. There was no significant alteration of fibroblasts in the portal tracts. In the middle and late stages of ASMN, the spindle-shaped ASMA-positive Ito cells formed a continuous cellular network. New fibre formation was predominantly around them. In this immediate postnecrotic fibrosis, ASMA-positive stromal cells of Ito cell origin were distributed irregularly and were closely associated with reticulin and newly-formed collagen fibres. Regenerative nodules were surrounded by dense layers of ASMA-positive stromal cells. Throughout the stages of ASMN, portal fibroblasts remained negative for ASMA. We believe that Ito cells in necrotic areas show myofibroblastic transformation and play a central role in the postnecrotic liver fibrosis. Portal fibroblasts play no significant part in this type of fibrosis.
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Abstract
The association between human leukocyte antigens and primary biliary cirrhosis is controversial, but major histocompatibility complex class II antigen DR8 was recently reported to be associated with increased susceptibility for primary biliary cirrhosis in some Caucasians and Japanese. Accordingly, we performed DNA typing of HLA class II genes in Japanese patients with primary biliary cirrhosis. The genotypes of HLA DRB1, DRB3-5, DQA and DQB were determined by polymerase chain reaction and subsequent hybridization with sequence specific oligonucleotides in 31 primary biliary cirrhosis patients and 215 racially matched local controls. DR8 was found in 24 of the 31 primary biliary cirrhosis patients and was highly concentrated in DRB1*0803. The gene frequency of DRB1*0803 was significantly increased in the patients (35.5% vs 7.4%, relative risk = 6.84, p < 0.0001). DQA1*0103 and DQB1*0601 were also increased in the primary biliary cirrhosis patients, in relation to linkage disequilibrium with DRB1*0803 on the same haplotype. In contrast, DQA1*0102 showed a significantly lower frequency in the primary biliary cirrhosis patients (p < 0.05). These data suggest that DRB1*0803 is one of the HLA class II genes related to an increased risk of primary biliary cirrhosis in Japanese individuals.
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Appearance of sinusoidal inclusion-containing endothelial cells in liver disease. Hepatology 1994; 20:604-10. [PMID: 7521315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
Abstract
Sinusoidal "inclusion-containing endothelial cells" were studied histopathologically and immunohistochemically in various liver diseases, and their clinical importance was investigated. A total of 498 needle liver biopsies were examined. Endothelial inclusions inside the cells were recognized as eosinophilic granules in hematoxylin-eosin-stained sections. Electron microscopy showed that these inclusions corresponded to round cytoplasmic dense bodies with a single limiting membrane. The contents of these bodies were generally homogeneous, but sometimes heterogeneous. The inclusions appeared to contain protein, but were resistant to trypsin digestion, and immunohistochemistry failed to identify any immunoglobulins or hepatocyte-derived proteins. These endothelial cells also contained an increased number of micropinocytotic vesicles when compared with ordinary cells. The inclusion-containing endothelial cells appeared frequently in chronic hepatitis, but were relatively rare in other liver diseases. The incidence was higher in chronic aggressive hepatitis than in chronic persistent hepatitis or inactive cirrhosis. Although the density of these cells varied considerably even among patients with the same histological diagnosis and the phenotypical changes of these endothelial cells, assessed by monoclonal antibodies, were not apparent, the serum gamma globulin level tended to increase in relation to the density of inclusion-containing endothelial cells and the correlation was significant in hepatitis C.
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Abstract
The serum level of alpha-L-fucosidase activity has been suggested as a useful marker in the diagnosis of hepatocellular carcinoma, although the precise mechanism behind the elevation of this parameter has not been determined. We found that the serum alpha-L-fucosidase activity level was significantly higher in 67 patients with hepatocellular carcinoma (695.1 +/- 245.5 nmol/ml/hr) than in 47 patients with cirrhosis (389.1 +/- 188.2 nmol/ml/hr; p < 0.001) and in 54 controls (202.0 +/- 104.6 nmol/ml/hr; p < 0.001). However, alpha-L-fucosidase activity was not correlated with tumor size (r = 0.134), whereas the alpha-fetoprotein level was correlated with tumor size (r = 0.580, p < 0.001). When 515.8 nmol/ml/hr was taken as the cutoff value (mean value in the controls plus 3 standard deviations), alpha-L-fucosidase activity was above the cutoff value in 12 of the 17 patients with a hepatocellular carcinoma less than 2 cm in diameter, in 28 of the 37 patients with a hepatocellular carcinoma less than 3 cm in diameter and in 52 of the 67 patients with hepatocellular carcinoma. In contrast, only 10 of the 47 patients with cirrhosis had levels above the cutoff value. These findings suggest that an increase in serum alpha-L-fucosidase activity in patients with cirrhosis may be a marker for detecting a hepatocellular carcinoma, especially a small tumor, because alpha-fetoprotein and des-gamma-carboxy-prothrombin are less promising as tumor markers.
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Abstract
The purpose of this study is to clarify the morphological characteristics and functional significance of the perisinusoidal stromal cells in hepatocellular carcinoma. The liver specimens surgically resected from 24 patients with hepatocellular carcinoma were studied by electron microscopy and immunohistochemistry using monoclonal antibodies against alpha-smooth muscle actin, vimentin and desmin. In the tissue space between endothelial cells and trabeculae of cancer cells, the stromal cells were frequently found. They were strongly positive for alpha-smooth muscle actin, weakly and less frequently positive for vimentin but negative for desmin. They varied in shape, size and distribution, stretching cytoplasmic processes and occasionally surrounding the trabeculae of cancer cells. They contained considerable amounts of microfilaments that were positive for alpha-smooth muscle actin and condensed in cell periphery. Along the cell membrane, the short dense areas and pinocytotic vesicles were seen. The external lamina incompletely invested the stromal cells. They were always surrounded by amorphous material. In the granulation tissue and fibrotic areas around necrotic cancer tissue, they were increased in size and number. On the other hand, immunohistochemically and ultrastructurally, they closely resembled the Ito cells in the piecemeal necrosis that showed myofibroblastic transformation. These results suggest that the perisinusoidal stromal cells in nonnecrotic cancer tissue produce the extracellular matrix in the tissue space and maintain the cancerous trabecular structure. After necrosis of cancer tissue, they may become activated and actively participate in the fibrosis.
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Abstract
The purpose of this study is to clarify the morphological characteristics and functional significance of the perisinusoidal stromal cells in hepatocellular carcinoma. The liver specimens surgically resected from 24 patients with hepatocellular carcinoma were studied by electron microscopy and immunohistochemistry using monoclonal antibodies against alpha-smooth muscle actin, vimentin and desmin. In the tissue space between endothelial cells and trabeculae of cancer cells, the stromal cells were frequently found. They were strongly positive for alpha-smooth muscle actin, weakly and less frequently positive for vimentin but negative for desmin. They varied in shape, size and distribution, stretching cytoplasmic processes and occasionally surrounding the trabeculae of cancer cells. They contained considerable amounts of microfilaments that were positive for alpha-smooth muscle actin and condensed in cell periphery. Along the cell membrane, the short dense areas and pinocytotic vesicles were seen. The external lamina incompletely invested the stromal cells. They were always surrounded by amorphous material. In the granulation tissue and fibrotic areas around necrotic cancer tissue, they were increased in size and number. On the other hand, immunohistochemically and ultrastructurally, they closely resembled the Ito cells in the piecemeal necrosis that showed myofibroblastic transformation. These results suggest that the perisinusoidal stromal cells in nonnecrotic cancer tissue produce the extracellular matrix in the tissue space and maintain the cancerous trabecular structure. After necrosis of cancer tissue, they may become activated and actively participate in the fibrosis.
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Immunohistochemical identification of Ito cells and their myofibroblastic transformation in adult human liver. Virchows Arch 1994; 424:249-56. [PMID: 8186890 DOI: 10.1007/bf00194608] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
To identify Ito cells in normal and pathological adult human livers, immunohistochemical studies were performed by the avidin-biotin-peroxidase complex method using monoclonal antibodies for alpha-smooth muscle actin (ASMA), desmin, and vimentin. Fifty one needle biopsies, 7 surgically resected specimens, and 5 autopsy specimens were studied. In the normal adult liver vascular smooth muscle cells and pericytes, together with perisinusoidal cells with thin cytoplasmic processes were positive for ASMA. These latter cells formed a loose and discontinuous layer along the sinusoidal walls. Immunoelectron microscopy showed that the ASMA-positive perisinusoidal cells were Ito cells containing fat droplets. The other sinusoidal lining cells were negative for ASMA. In chronic liver disease, ASMA-positive Ito cells showed an increase in number, size, and the intensity of immunostaining in areas of piece-meal necrosis), and formed a continuous cellular network. These cells were dendritic in shape with irregularly elongated cytoplasmic processes and contained an increased amount of microfilaments, in association with loss of the characteristic fat droplets. Thus, their ultrastructural features corresponded to those of myofibroblastic cells. Ito cells showed no staining for desmin in both normal and pathological livers. These results indicate that immunohistochemistry using an anti-ASMA antibody is a sensitive and reliable method for the identification of both normal and transformed Ito cells in adult human livers.
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Cytotoxic activity of spleen-derived T lymphocytes against autologous biliary epithelial cells in autopsy patients with primary biliary cirrhosis. LIVER 1993; 13:188-92. [PMID: 8377595 DOI: 10.1111/j.1600-0676.1993.tb00629.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Autoimmunity against biliary epithelial cells is considered to be involved in the pathogenesis of primary biliary cirrhosis (PBC). However, cytotoxic activity of T lymphocytes against biliary epithelial cells has not previously been examined. This study has demonstrated that spleen-derived T lymphocytes were cytotoxic for autologous biliary epithelial cells in all of five patients with PBC, even though it was only detectable at high effector to target ratios. Such cytotoxicity was not found in non-PBC patients. CD8-positive T lymphocytes were shown to be responsible for the cytotoxicity by negative selection, and its inhibition was dependent on the ratio of cold to hot target cells. These observations may support a current hypothesis that the pathogenesis of PBC is partly due to T cell autoimmunity directed against the bile duct epithelium.
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Changes in the level of plasma cortisol, progesterone and total testosterone in developing hairless dogs. J Vet Med Sci 1992; 54:1217-8. [PMID: 1477175 DOI: 10.1292/jvms.54.1217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Changes in the levels of plasma cortisol, progesterone and total testosterone were examined in developing hairless and haired dogs. Cortisol levels in the hairless dogs seemed to be higher than those in haired dogs within the age of 4-5 weeks. No apparent changes were seen in the level of plasma progesterone between the groups of hairless females and haired females. Total testosterone levels in hairless males showed to be significantly lower than those in haired males at the age of 13-21 weeks.
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Effects of TZI-41127, a novel selective 5-lipoxygenase inhibitor, on A23187-induced pleurisy in rats. Eur J Pharmacol 1991; 199:69-75. [PMID: 1909963 DOI: 10.1016/0014-2999(91)90638-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Intrapleural injection of the ionophore A23187 in rats induced leukotriene (LT) production, prostaglandin E2 production, plasma exudation and leukocyte accumulation in the pleural cavity. We evaluated the inhibitory effects of orally administered drugs on 5-lipoxygenase activity by their ability to reduce the content of both peptido-LTs (LTC4, LTD4 and LTE4) and LTB4 in this model. TZI-41127, a novel selective 5-lipoxygenase inhibitor, significantly reduced the peptido-LTs and LTB4 content with ED50 values of 4.2 and 6.1 mg/kg, respectively, whereas it only reduced the prostaglandin E2 content (cyclooxygenase activity) by 31.1% even after 100 mg/kg. Phenidone inhibited 5-lipoxygenase activity more selectively than cyclooxygenase activity. BW755C inhibited cyclooxygenase activity more selectively than 5-lipoxygenase activity. Indomethacin selectively inhibited cyclooxygenase activity. These results suggest that: (1) A23187-induced pleurisy is an convenient in vivo model for studying drug effects on 5-lipoxygenase and cyclooxygenase activities and (2) TZI-41127 is an orally active and comparatively selective inhibitor of 5-lipoxygenase activity.
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Response of the lactating and postweaning sow to gonadotropin releasing hormone (GnRH). J Vet Med Sci 1991; 53:181-4. [PMID: 1830788 DOI: 10.1292/jvms.53.181] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Clinical and endocrinological responses to administration of gonadotropin releasing hormone analog (LH-RH-A) during the lactation period and postweaning in the sow were investigated. Plasma LH concentrations in lactating sows rose immediately after administration of LH-RH-A. However, in postweaning sows the increase of LH level was more slowly. Three of 5 postweaning sows came into estrus and ovulated after LH-RH-A treatment. One sow exhibited a distinct LH response, but her ovaries remained quiescent. The remaining one with feeble estrus for a short period became cystic ovaries. Thus, LH response to GnRH in the sow seems to be higher during early lactation than at 2 days postweaning.
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[Analysis of proliferative potential of trophoblast using anti-PCNA/cyclin monoclonal antibodies in fixed, embedded tissues]. NIHON SANKA FUJINKA GAKKAI ZASSHI 1991; 43:355-6. [PMID: 1675230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Platelet-activating factor (PAF)-induced rhinitis and involvement of PAF in allergic rhinitis in guinea pigs. JAPANESE JOURNAL OF PHARMACOLOGY 1990; 54:217-26. [PMID: 2077186 DOI: 10.1254/jjp.54.217] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The effects of inhaled PAF on the guinea pig nasal mucosa were investigated. Intranasal pressure (INP) was recorded as an index of intranasal resistance. To access the capillary premeability of nasal mucosa, exudation of Evans blue into the nasal lavage fluid was determined. Inhalations of histamine and PAF markedly and significantly increased INP and dye exudation into the nasal cavities. The two responses to PAF were about 20-fold and 70-fold stronger than those of histamine, respectively. A PAF antagonist, CV-3988, significantly antagonized both the PAF-induced increases in INP and dye exudation. Indomethacin and OKY-046 had no effect on the PAF-induced responses. FPL-55712 inhibited the PAF-induced increases in INP and dye exudation by 52% and 40%, respectively. Ovalbumin (OA) antigen challenge by inhalation to sensitized guinea pigs resulted in significant increases in both INP and dye exudation. These two responses to 30 mg/ml OA were inhibited by CV-3988 (10 mg/kg, i.v.) by 55% and 40%, respectively. From the above results, it is indicated that: 1) inhalation of PAF evokes rhinitis-like symptoms through activation of PAF receptors, 2) the PAF-induced rhinitis is, in a part, mediated by leukotrienes, and 3) PAF might be involved in allergic rhinitis.
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Platelet-activating factor (PAF) induced rhinitis and involvement of PAF in allergic rhinitis in guinea pigs. Eur J Pharmacol 1990. [DOI: 10.1016/0014-2999(90)94270-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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