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1.
Rev Sci Instrum ; 92(5): 053506, 2021 May 01.
Article in English | MEDLINE | ID: mdl-34243319

ABSTRACT

In the GAMMA 10/PDX tandem mirror, plasma with strong ion-temperature anisotropy is produced by using the ion cyclotron range of frequency waves. This anisotropy of ion temperature causes several Alfvén-Ion-Cyclotron (AIC) waves to spontaneously excite in the frequency range just below the ion cyclotron frequency. In addition, difference-frequency (DF) waves are excited in the radial inner region of the plasma by wave-wave coupling among the AIC waves. The radial density profiles were measured at multi-axial positions using a frequency-modulation reflectometer with an axial array of microwave antennas, and an axial variation of the density was found to be significant. In addition, a relative phase difference of the DF wave between axially separated two points was first obtained by finely choosing the probing frequency of the reflectometers with a maximum coherence used as a measure, indicating that the DF wave is a propagating wave, while the pump AIC waves are standing waves in the axial region of measurement.

2.
Transplant Proc ; 50(10): 4067-4070, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30577317

ABSTRACT

Elevated panel-reactive antibody (PRA) levels serve as a significant risk factor for allograft survival and episodes of rejection after heart transplantation (HTX). Patients with high PRA levels tend to show expressions of donor-specific human leukocyte antigen antibodies (DSA), which can cause catastrophic hyperacute rejection after HTX. Therefore, such highly sensitized patients are required to undergo strategic perioperative desensitization therapy. We describe a successful HTX after desensitization in a patient with extremely high PRA levels and pretransplant DSA positivity.


Subject(s)
Desensitization, Immunologic/methods , HLA Antigens/immunology , Heart Transplantation/methods , Adult , Antibodies , Female , Graft Rejection/immunology , Graft Survival/immunology , Humans , Transplantation, Homologous
3.
Transplant Proc ; 50(9): 2839-2841, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30401408

ABSTRACT

Pigs have recently become very popular for use not only in xenotransplantation field, but in regeneration studies as well, sometimes with pigs being used as the scaffold. We have already presented our findings related to the pig immune system against human cells, including the complement systems, natural antibodies (NAs), and NK cells. In this study, we investigated the pig innate immunological reaction against human cells further. Our investigations included issues such as the production of NAs in newborns, day 0 and day 1, and sow colostrum. The alternative pathway for pig complement reacted with human cells, and pig NK cells and macrophages directly injured human aortic endothelial cells. Pig serum clearly contains the natural antibodies IgG and IgM to human peripheral blood mononuclear cells (PBMCs). Pig plasma from day 1 newborns contained almost the same levels of these natural antibodies to human PBMCs as those of sow plasma. On the other hand, pig plasma from day 0 newborns did not contain IgG and IgM to human PBMCs. In addition, sow colostrum clearly contained both IgG and IgM to human PBMCs. As expected, the pig innate immunity system reacted to human cells, including natural antibodies. However, the NAs of pigs, both IgM and IgG, against human cells do not exist in pig serum at day 0, but at day 1 and in mother's milk, indicating that NAs in newborns did not come from the placenta but from sow colostrum.


Subject(s)
Colostrum/immunology , Immunity, Innate/immunology , Swine/immunology , Transplantation Immunology/immunology , Transplantation, Heterologous , Animals , Animals, Newborn , Female , Humans , Immunoglobulin G/blood , Immunoglobulin G/immunology , Immunoglobulin M/blood , Immunoglobulin M/immunology , Leukocytes, Mononuclear/immunology , Pregnancy
4.
Physiol Int ; 105(2): 177-187, 2018 Jun 01.
Article in English | MEDLINE | ID: mdl-29975126

ABSTRACT

The purpose of this study was to examine the effects of submaximal cycling at different exercise intensities on maximal isometric force output of the non-exercised elbow flexor muscles after the cycling. A total of 8 healthy young men performed multiple maximal voluntary contractions by the right elbow flexion before, immediately after, 5 min after, and 10 min after a 6-min submaximal cycling at ventilatory threshold (LI), 70% [Formula: see text] (MI), and 80% [Formula: see text] (HI) with both arms relaxed in the air. Force and surface electromyogram (EMG) of the right biceps brachii muscle during the multiple MVCs, blood lactate concentration ([La]), cardiorespiratory responses, and sensations of fatigue for legs (SEF-L) were measured before, immediately after, 5 min after, and 10 min after the submaximal cycling with the three different exercise intensities. Immediately after the submaximal cycling, [La], cardiorespiratory responses, and SEF-L were enhanced in proportion to an increase in exercise intensity of the cycling. Changes in force and EMG activity during the multiple MVCs were not significantly different across the three conditions. The findings imply that group III/IV muscle afferent feedback after the submaximal cycling does not determine the magnitude of MVC force loss of the non-exercised upper limb muscles.


Subject(s)
Isometric Contraction/physiology , Muscle Fatigue/physiology , Muscle, Skeletal/physiology , Arm , Bicycling , Elbow , Humans , Male , Young Adult
5.
Transplant Proc ; 49(1): 135-138, 2017.
Article in English | MEDLINE | ID: mdl-28104121

ABSTRACT

BACKGROUND: Patients with intestinal failure (IF) are candidates for intestinal transplantation (ITx). In Japan, these patients have few opportunities to undergo cadaveric ITx because of low rates of organ donation. The donor criteria and recipient priority for ITx are still unknown. We reviewed our cases of IF to investigate which patients should be prioritized for ITx. METHODS: Patients with IF who were registered as candidates for cadaveric ITx between January 2010 and November 2015 in our institute were included in this retrospective study. Their data were gathered from their charts and analyzed. RESULTS: Five patients were included. Their primary diseases included total colon aganglionosis (n = 1), chronic idiopathic intestinal pseudo-obstruction syndrome (n = 2), superior mesenteric vein embolization (n = 1), and graft loss after ITx (n = 1). Two patients died of liver failure (LF) during the waiting period. The remaining three are now alive and waiting for transplantation. The lengths of the remaining intestine were more than 20 cm in living cases but less than 20 cm in fatal cases. In the fatal cases, they had several episodes of catheter-related blood stream infection, which caused LF and acute renal failure. CONCLUSIONS: We identified two patients with less than 20 cm residual small bowel who died after acute deterioration of liver function. Patients with ultra-short bowel could have a higher risk of LF. Therefore, they should be referred as soon as possible to a specialized hospital where ITx is a choice of treatment for IF.


Subject(s)
Intestine, Small/transplantation , Liver Failure/epidemiology , Liver Failure/etiology , Short Bowel Syndrome/complications , Waiting Lists , Adult , Chronic Disease , Female , Humans , Japan , Male , Middle Aged , Retrospective Studies , Short Bowel Syndrome/mortality , Treatment Outcome
6.
Transplant Proc ; 48(4): 1279-81, 2016 May.
Article in English | MEDLINE | ID: mdl-27320603

ABSTRACT

BACKGROUND: The purpose of this study was to produce molecules that can precisely regulate the complement and coagulation system and to assess the expression of such molecules in transgenic animals. METHODS: The CTDM gene, which is composed of the delta-1-99 amino acid (aa) C1-INH, EGF domain 4-6 of thrombomoduline (TM), short consensus repeat (SCR) 2-4 of DAF(CD55), and SCR 2-4 of MCP(CD46) was established. The codon usage for expression in mammals was adopted. The cDNA of CTDM was subcloned into the pCPI site (the human insulin promoter and a cytomegalovirus enhancer). pCPI-CTDM was transfected into pig endothelial cells (PEC). The expression of the molecule was clearly assessed by means of flow cytometry. RESULTS: BD3F1 female mice were induced to superovulate and were then crossed with BD3F1 males. Micro-injection and embryo transfer were performed by standard methods, thus generating transgenic mice that express CTDM. The mice carried the CTDM plasmid, as verified by PCR. Tissue expression levels in transgenic mouse lines generated with the constructs were follows: pancreas, 1.0; brain, 5.4; thymus, 0.3; heart, 0.2; lung, 1.2; liver, 0.1; kidney, 0.1; intestine, 0.4; and spleen, 1.6. A naive control mouse was also analyzed in the exact manner as for the transgenic mice. CONCLUSIONS: A synthetic CTDM gene with codon usage optimized to the mammalian system represents a critical factor in the development of transgenic animals.


Subject(s)
Blood Coagulation/genetics , Complement System Proteins/genetics , Genes, Synthetic/genetics , Animals , CD55 Antigens/genetics , Cloning, Molecular , DNA, Complementary/genetics , Endothelial Cells/metabolism , Female , Flow Cytometry , Homeodomain Proteins/genetics , Humans , Male , Membrane Cofactor Protein/genetics , Mice , Mice, Transgenic , Promoter Regions, Genetic , Swine , Thrombomodulin/genetics , Transfection/methods , Transplantation, Heterologous
7.
Transplant Proc ; 48(4): 1282-4, 2016 May.
Article in English | MEDLINE | ID: mdl-27320604

ABSTRACT

BACKGROUND: On the basis of a comparison of the hemolytic complement titer in pigs with that in humans, the complement system of pigs was investigated. The response of innate immunity, such as the natural antibodies, against humans was also examined. METHODS: Hemolytic complement activity of pig serum was measured with the use of a microtitration technique. CH50 was determined according to the method of Mayer. ACH50 was assayed according to the methods of Platts-Milles and Ishizaka. Hemolytic activities of C1, C4, C2, C3, C5, C8, and C9 were estimated through the use of intermediate cells and reagents, as described previously. In addition, the pig natural anti-human antibody was studied with the use of human peripheral blood mononuclear cells (PBMCs). Human PBMCs were stained with 5% pig serum, followed by staining with fluorescein isothiocyanate-labeled goat anti-pig IgG and IgM. The resulting stained cells were quantified by use of a FACScalibur system. The alternative pathway of pig complement was also measured with the use of human erythrocytes and normal pooled pig serum with or without Mg(++)EGTA. RESULTS: Both the CH50 and ACH50 titers were lower than those of humans. Concerning the components, except for C3, each component, that is, C1, C4, C2, C5, C8, and C9, was also lower than that of humans, based on measured values for human complement components. Pig serum clearly contains natural antibodies, IgG and IgM, to human PBMCs. The alternative pathway of pig complement reacted with human erythrocytes. CONCLUSIONS: As a whole, pig innate immunity, the complement system and natural antibody, recognizes the surfaces of human cells.


Subject(s)
Complement System Proteins/immunology , Hemolysis/immunology , Immunity, Innate/immunology , Animals , Antibodies, Anti-Idiotypic/metabolism , Complement Activation/immunology , Complement Hemolytic Activity Assay , Complement System Proteins/metabolism , Erythrocytes/immunology , Fibronectins/metabolism , Humans , Leukocytes, Mononuclear/immunology , Recombinant Proteins/metabolism , Sus scrofa , Swine
8.
Transplant Proc ; 48(4): 1285-7, 2016 May.
Article in English | MEDLINE | ID: mdl-27320605

ABSTRACT

The inhibitory function of HLA-G1, a class Ib molecule, on monocyte/macrophage-mediated cytotoxicity was examined. The expression of inhibitory receptors that interact with HLA-G, immunoglobulin-like transcript 2 (ILT2), ILT4, and KIR2DL4 (CD158d) on in vitro-generated macrophages obtained from peripheral blood mononuclear cells and the phorbol 12-myristate 13-acetate (PMA)-activated THP-1 cells were examined by flow cytometry. cDNAs of HLA-G1, HLA-G3, HLA-E, and human ß2-microglobulin were prepared, transfected into pig endothelial cells (PECs), and macrophage- and the THP-1 cell-mediated PEC cytolysis was then assessed. In vitro-generated macrophages expressed not only ILT2 and ILT4 but CD158d as well. The transgenic HLA-G1 on PEC indicated a significant suppression in macrophage-mediated cytotoxicity, which was equivalent to that of transgenic HLA-E. HLA-G1 was clearly expressed on the cell surface of PEC, whereas the levels of HLA-G3 were much lower and remained in the intracellular space. On the other hand, the PMA-activated THP-1 cell was less expressed these inhibitory molecules than in vitro-generated macrophages. Therefore, the HLA-G1 on PECs showed a significant but relatively smaller suppression to THP-1 cell-mediated cytotoxicity compared to in vitro-generated macrophages. These results indicate that by generating HLA-G1, but not HLA-G3, transgenic pigs can protect porcine grafts from monocyte/macrophage-mediated cytotoxicity.


Subject(s)
HLA-G Antigens/physiology , Leukocytes, Mononuclear/immunology , Macrophages/immunology , Animals , Animals, Genetically Modified , Antigens, CD/metabolism , Cytokines/metabolism , Cytotoxicity, Immunologic/physiology , Endothelial Cells/immunology , Endothelium/immunology , Flow Cytometry , HLA-G Antigens/metabolism , Humans , Killer Cells, Natural/immunology , Leukocyte Immunoglobulin-like Receptor B1 , Membrane Glycoproteins/metabolism , Receptors, Immunologic/metabolism , Receptors, KIR2DL4/metabolism , Swine , Transfection/methods
9.
Transplant Proc ; 48(4): 1302-3, 2016 May.
Article in English | MEDLINE | ID: mdl-27320609

ABSTRACT

The pig pancreas is considered to be one of the most suitable sources of islets for clinical xenotransplantation. However, after producing α1-3galactosyltransferase knockout pigs, most of the organs of these pigs showed less antigenicity to the human body. Wild-type adult pig islets (APIs) that originally produced negligible levels of α-Gal, different from neonatal porcine islet-like cell clusters, showed a clear antigenicity to human serum. Concerning the so-called non-Gal epitopes, many studies related to glycoproteins and glycolipids are ongoing in efforts to identify them. However, our knowledge of non-Gal glycoantigens remains incomplete. In our previous study, N-glycans were isolated from APIs, and the structures of 28 of the N-glycans were detected. In this study, to identify additional structures, further analyses were performed by liquid chromatography-mass spectrometry (LC-MS). N-glycans were isolated from APIs by the method described by O'Neil et al with minor modifications and LC-MS-based structural analyses were then performed. The detected N-glycan peaks in the LC-MS spectra were selected using the FLexAnalysis software program and the structures of the glycans were predicted using the GlyocoMod Tool. The API preparation contained 11 peaks and 16 structures were then nominated as containing N-linked sugars. Among them, 5 sulfated glycans were estimated, confirming the existence of sulfate structures in N-glycans in API. In addition, these data may supplement several N-glycan structures that contain two deoxyhexose units, such as fucose, to our previous report. The data herein will be helpful for future studies of antigenicity associated with API.


Subject(s)
Islets of Langerhans/chemistry , Polysaccharides/metabolism , Animals , Epitopes/metabolism , Glycoproteins/metabolism , Humans , Mass Spectrometry , Sus scrofa , Swine , Transplantation, Heterologous
10.
Transplant Proc ; 48(4): 1320-2, 2016 May.
Article in English | MEDLINE | ID: mdl-27320613

ABSTRACT

BACKGROUND: We attempted to knock out the expression of Hanganutziu-Deicher (H-D) antigens through the use of a CRISPR (clustered regulatory interspaced short palindromic repeat)/Cas9 system for pig cytidine monophospho-N-acetylneuraminic acid hydroxylase (CMAH). METHODS: Plasmids expressing hCas9 and sgRNA for pCMAH were prepared by ligating oligos into the BbsI site of pX330. The N-terminal and C-terminal EGFP coding regions overlapping 482 bp were PCR-amplified and placed under a ubiquitous CAG promoter. The approximately 400-bp genomic fragments containing the sgRNA target sequence of pCMAH were placed into the multi-cloning sites flanked by the EGFP fragments. The pCAG-EGxxFP-target was mixed with pX330 with/without the sgRNA sequences and then introduced into HEK293T cells. RESULTS: Four oligos and primers, gSO1, gSO3, gSO4, and gSO8, were nominated from 8 candidates. Among them, gSO1 showed the best efficiency. Pig endothelial cells (PECs) from an α-Gal knockout pig were then used to examine the changes in the expression of the H-D antigen by the knockout of the CMAH genome by the pX330-gS01. CONCLUSIONS: Changes in the expression of the H-D antigen in the PECs with the CRISPR (gS01) were clear in comparison with those in the parental cells, on the basis of FACS analysis data. The expression of the H-D antigen can be knocked out by use of the CRISPR system for pCMAH, thus confirming that this system is a very convenient system for producing knockout pigs.


Subject(s)
Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Mixed Function Oxygenases/deficiency , Animals , Antigens, Heterophile/metabolism , Base Sequence , Endothelial Cells/immunology , Gene Knockout Techniques , HEK293 Cells , Humans , Mixed Function Oxygenases/genetics , N-Acetylneuraminic Acid/metabolism , Open Reading Frames/genetics , Polymerase Chain Reaction , RNA, Messenger/metabolism , Sus scrofa , Swine
11.
Transplant Proc ; 48(4): 1323-5, 2016 May.
Article in English | MEDLINE | ID: mdl-27320614

ABSTRACT

BACKGROUND: In our previous study, we reported on the development of substituting S147C for HLA-E as a useful gene tool for xenotransplantation. In this study we exchanged the codon of HLA-Ev (147), checked its function, and established a line of transgenic mice. METHODS: A new construct, a codon exchanging human HLA-Ev (147) + IRES + human beta 2-microgloblin, was established. The construct was subcloned into pCXN2 (the chick beta-actin promoter and cytomegalovirus enhancer) vector. Natural killer cell- and macrophage-mediated cytotoxicities were performed using the established the pig endothelial cell (PEC) line with the new gene. Transgenic mice with it were next produced using a micro-injection method. RESULTS: The expression of the molecule on PECs was confirmed by the transfection of the plasmid. The established molecules on PECs functioned well in regulating natural killer cell-mediated cytotoxicity and macrophage-mediated cytotoxicity. We have also successfully generated several lines of transgenic mice with this plasmid. The expression of HLA-Ev (147) in each mouse organ was confirmed by assessing the mRNA. The chick beta-actin promoter and cytomegalovirus enhancer resulted in a relatively broad expression of the gene in each organ, and a strong expression in the cases of the heart and lung. CONCLUSION: A synthetic HLA-Ev (147) gene with a codon usage optimized to a mammalian system represents a critical factor in the development of transgenic animals for xenotransplantation.


Subject(s)
Animals, Genetically Modified/genetics , Codon/genetics , Histocompatibility Antigens Class I/metabolism , Actins/genetics , Animals , Animals, Genetically Modified/immunology , Cell Line , Cytomegalovirus , Endothelial Cells/metabolism , Enhancer Elements, Genetic/genetics , Genes, Synthetic , Humans , Killer Cells, Natural/physiology , Macrophages/physiology , Mice , Promoter Regions, Genetic/genetics , Swine , Transfection , Transplantation, Heterologous , HLA-E Antigens
12.
Transplant Proc ; 48(1): 251-4, 2016.
Article in English | MEDLINE | ID: mdl-26915877

ABSTRACT

BACKGROUND: Hypercalcemia has been observed in patients after liver transplantation. However, it is rare that the hypercalcemia induced disseminated tissue calcification and heart failure. CASE REPORT: We report a rare case of heart failure caused by disseminated metastatic tissue calcification that involved extensive progressive myocardial calcification after liver transplantation. A 20-year-old man with end-stage liver disease due to biliary atresia underwent ABO-incompatible living donor liver transplantation. After successful transplantation, he suffered from antibody-mediated rejection. Subsequently, ABO-matched cadaveric liver retransplantation was successfully performed. Hypercalcemia developed gradually following the second transplantation. His serum calcium level increased to 18.3 mg/dL with sudden onset of ventricular tachycardia. Although he was resuscitated with a cardiopulmonary support device, he died of heart and liver failure. Histopathologic examination revealed systemic disseminated metastatic tissue calcification, including massive myocardial calcification. CONCLUSION: Progressive worsening of hypercalcemia resulted in disseminated metastatic tissue calcification and massive metastatic myocardial calcification, which led to heart failure after liver transplantation. Because hypercalcemia after liver transplantation can cause fatal tissue calcification, early intervention for hypercalcemia should be considered.


Subject(s)
Calcinosis/etiology , Cardiomyopathies/etiology , Hypercalcemia/etiology , Liver Failure/surgery , Liver Transplantation/adverse effects , Adult , Biliary Atresia/complications , Blood Group Incompatibility/complications , Calcium/blood , Fatal Outcome , Graft Rejection/complications , Graft Rejection/immunology , Graft Rejection/surgery , Heart Failure/etiology , Humans , Liver/pathology , Liver Failure/etiology , Liver Transplantation/methods , Living Donors , Male , Reoperation/adverse effects , Reoperation/methods , Tachycardia, Ventricular/blood , Tachycardia, Ventricular/etiology
13.
Biol Sport ; 32(1): 15-20, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25729145

ABSTRACT

The aim of this study was to investigate the effects of heat exposure in the absence of hyperthermia on power output during repeated cycling sprints. Seven males performed four 10-s cycling sprints interspersed by 30 s of active recovery on a cycle ergometer in hot-dry and thermoneutral environments. Changes in rectal temperature were similar under the two ambient conditions. The mean 2-s power output over the 1st-4th sprints was significantly lower under the hot-dry condition than under the thermoneutral condition. The amplitude of the electromyogram was lower under the hot-dry condition than under the thermoneutral condition during the early phase (0-3 s) of each cycling sprint. No significant difference was observed for blood lactate concentration between the two ambient conditions. Power output at the onset of a cycling sprint during repeated cycling sprints is decreased due to heat exposure in the absence of hyperthermia.

14.
Acta Physiol Hung ; 100(1): 54-63, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23471041

ABSTRACT

The purpose of the present study was to determine the effects of deception for exercise intensity on surface electromyogram (SEMG) activity and blood lactate concentration during intermittent cycling exercise (ICE) tests. Sixteen healthy male were randomly assigned to two groups who completed two ICE [three 4-min cycling at 80% peak power output (PPO) with 3-min passive recovery periods followed by exhaustive cycling] tests (ICE-1 and ICE-2). The experimental group (ICED) was deceived of the actual cycling intensity, while the control group (ICEC) was informed of the actual protocol in ICE-2. In ICE-1, both groups were informed of the actual protocol. In ICE-2, root mean square (RMS) calculated from SEMG during submaximal cycling was significantly higher in the ICEC than in the ICED and blood lactate concentration ([La-]) was significantly higher in the ICEC than in the ICED. In particular, the difference in RMS between the groups was also observed during the first 4-min cycling, in which there was no difference in [La-] between the groups. These results suggest that the CNS modulates skeletal muscle recruitment due to the prior deception for exercise intensity.


Subject(s)
Bicycling/physiology , Bicycling/psychology , Electromyography/methods , Electromyography/psychology , Exercise/physiology , Exercise/psychology , Lactic Acid/blood , Adult , Deception , Exercise Test/methods , Humans , Male , Muscle, Skeletal/physiology , Young Adult
15.
Kyobu Geka ; 64(7): 556-7, 2011 Jul.
Article in Japanese | MEDLINE | ID: mdl-21766706

ABSTRACT

The blood spurting from the ascending aorta is uncomfortable for cardiac surgeons. To protect the surgeons' faces from this spurting blood, we use a longitudinal half of a plastic bottle, which is semi see-through. While the assistant is holding this device above the ascending aorta, the surgeons can proceed the operation with good surgical view.


Subject(s)
Aorta/surgery , Blood , Face , General Surgery , Protective Devices , Humans
16.
Br J Sports Med ; 45(10): 820-4, 2011 Aug.
Article in English | MEDLINE | ID: mdl-19952377

ABSTRACT

OBJECTIVES: To determine the effects of resistive load on performance and surface electromyogram (SEMG) activity during repeated cycling sprints (RCS) on a non-isokinetic cycle ergometer. METHODS: Participants performed two RCS tests (ten 10-second cycling sprints) interspersed with both 30- and 360-second recovery periods under light (RCS(L)) and heavy load conditions (RCS(H)) in a random counterbalanced order. Recovery periods of 360 seconds were set before the fifth and ninth sprints. RESULTS: In the 9th and 10th sprints, the values of peak power output divided by body mass were significantly higher in RCS(H) than in RCS(L). Changes in blood lactate concentration were not different between the two conditions. In RCS(L), the root mean square calculated from the SEMG was significantly lower in the ninth sprint than in the first sprint, but there were no differences between the root mean square in the first sprint and that in the ninth sprint in RCS(H). CONCLUSIONS: During RCS on a non-isokinetic cycle ergometer, performance and SEMG activity are influenced by resistive load. It is thought that regulation of skeletal muscle recruitment by the central nervous system is associated with fatigue during RCS with a light resistive load.


Subject(s)
Athletic Performance/physiology , Bicycling/physiology , Muscle Fatigue/physiology , Muscle, Skeletal/physiology , Electromyography , Ergometry/methods , Exercise Test/methods , Humans , Lactic Acid/metabolism , Male , Oxygen Consumption/physiology , Random Allocation , Resistance Training , Young Adult
17.
Fish Physiol Biochem ; 36(3): 391-402, 2010 Sep.
Article in English | MEDLINE | ID: mdl-19288257

ABSTRACT

The development of rod and cone photoreceptor cells was investigated in the retinas of Pacific bluefin tuna larvae and juveniles, using RET-P1 monoclonal antibody labeling to identify photoreceptors. At 60 h after hatching, which was about when feeding began, opsin (presumably green opsin (Rh2)) was expressed in the outer segments of cone cells. At 15 days after hatching (dah), although many labeled cone cells were observed in the dorsal retina, the same type of cone cells had partially appeared in the ventral retina. The presence of rod cell bodies was confirmed by the expression of Rh1 opsin at 15 dah. At 21 dah, the presence of outer segments of rod cells was confirmed by the expression of Rh1 opsin and by morphology. The observations suggest that the cone cells were substantially operable upon the development of their outer segment at around the beginning of the post-larval stage, and the rod cells began to function at around 15 to 21 dah, before and during metamorphosis.


Subject(s)
Morphogenesis/physiology , Photoreceptor Cells, Vertebrate/physiology , Tuna/growth & development , Age Factors , Animals , Antibodies, Monoclonal , Histocytochemistry , Larva/growth & development , Opsins/metabolism
18.
J Med Eng Technol ; 33(6): 460-9, 2009.
Article in English | MEDLINE | ID: mdl-19479608

ABSTRACT

This study was undertaken to develop a method to quantitatively monitor the effect of inhibition of nitric oxide synthase (NOS) on tumour vascular activity using dynamic contrast-enhanced computed tomography (DCE-CT). The DCE-CT studies were performed in 13 anaesthetized rats bearing tumours. To investigate the effect of NOS inhibition, N-nitro-L-arginine (L-NNA) was intravenously administered in eight rats, while only the vehicle was administered in five rats. The contrast enhancement (CE) images were generated by subtracting the CT images before and after the administration of contrast agent. The tumour blood volume (TBV) images were also generated. The CE significantly decreased after L-NNA administration, while there were no significant changes when only the vehicle was administered. There was a good correlation between CE and TBV, suggesting that CE mainly reflects TBV. In conclusion, the present method appears to be useful for monitoring the effect of NOS inhibition on tumour vascular activity.


Subject(s)
Blood Volume/drug effects , Enzyme Inhibitors/pharmacology , Neoplasms/blood supply , Nitric Oxide Synthase/antagonists & inhibitors , Nitroarginine/pharmacology , Radiographic Image Enhancement/methods , Tomography, X-Ray Computed/methods , Animals , Male , Rats , Rats, Inbred F344
19.
Physiol Res ; 58(4): 537-543, 2009.
Article in English | MEDLINE | ID: mdl-18656996

ABSTRACT

To determine the relationship between hyperventilation and recovery of blood pH during recovery from a heavy exercise, short-term intense exercise (STIE) tests were performed after human subjects ingested 0.3 g.kg(-1) body mass of either NaHCO3 (Alk) or CaCO3 (Pla). Ventilation (VE)-CO2 output (VCO2) slopes during recovery following STIE were significantly lower in Alk than in Pla, indicating that hyperventilation is attenuated under the alkalotic condition. However, this reduction of the slope was the result of unchanged VE and a small increase in VCO2. A significant correlation between VE and blood pH was found during recovery in both conditions. While there was no difference between the VE-pH slopes in the two conditions, VE at the same pH was higher in Alk than in Pla. Furthermore, the values of pH during recovery in both conditions increased toward the preexercise levels of each condition. Thus, although VE-VCO2 slope was decreased under the alkalotic condition, this could not be explained by the ventilatory depression attributed to increase in blood pH. We speculate that hyperventilation after the end of STIE is determined by the VE-pH relationship that was set before STIE or the intensity of the exercise performed.


Subject(s)
Exercise/physiology , Hyperventilation/metabolism , Sodium Bicarbonate/pharmacology , Exercise Test , Humans , Hydrogen-Ion Concentration , Male , Oxygen Consumption/physiology , Sodium Bicarbonate/administration & dosage , Young Adult
20.
Physiol Res ; 58(4): 529-535, 2009.
Article in English | MEDLINE | ID: mdl-18657002

ABSTRACT

The purpose of the present study was to examine whether excessive CO2 output (VCO2excess) is dominantly attributable to hyperventilation during the period of recovery from repeated cycling sprints. A series of four 10-sec cycling sprints with 30-sec passive recovery periods was performed two times. The first series and second series of cycle sprints (SCS) were followed by 360-sec passive recovery periods (first recovery and second recovery). Increases in blood lactate (DeltaLa) were 11.17+/-2.57 mM from rest to 5.5 min during first recovery and 2.07+/-1.23 mM from the start of the second SCS to 5.5 min during second recovery. CO2 output (VCO2) was significantly higher than O2 uptake (VO2) during both recovery periods. This difference was defined as VCO2excess. VCO2excess was significantly higher during first recovery than during second recovery. VCO2excess was added from rest to the end of first recovery and from the start of the second SCS to the end of second recovery (CO2excess). DeltaLa was significantly related to CO2excess (r=0.845). However, ventilation during first recovery was the same as that during second recovery. End-tidal CO2 pressure (PETCO2) significantly decreased from the resting level during the recovery periods, indicating hyperventilation. PETCO2 during first recovery was significantly higher than that during second recovery. It is concluded that VCO2excess is not simply determined by ventilation during recovery from repeated cycle sprints.


Subject(s)
Bicycling , Carbon Dioxide/metabolism , Hyperventilation/metabolism , Exercise Tolerance , Humans , Lactic Acid/blood , Male , Oxygen Consumption , Young Adult
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