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1.
J Appl Microbiol ; 118(2): 506-14, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25376258

ABSTRACT

AIMS: This study aimed to identify the main active component of Lactobacillus brevis KB290 (KB290) that is responsible for enhanced cell-mediated cytotoxic activity of mouse splenocytes Live KB290, a probiotic strain derived from a Japanese traditional pickle, was previously reported to modulate innate immune responses as affecting on cell-mediated cytotoxic activity of mouse splenocytes. METHODS AND RESULTS: We used live KB290, heat-killed KB290, a derivative strain (Lact. brevis KB392) with different amounts of cell-bound exopolysaccharide (EPS-b), and a crude extract of EPS-b from KB290 cell surface. Female BALB/c mice were fed a diet containing 10(10) CFU live KB290, 10(10) CFU live KB392, 15 mg heat-killed KB290 or 600 µg crude extract of EPS-b for 1 day. Live KB290 (P < 0.01), heat-killed KB290 (P < 0.05) and crude EPS-b at 600 µg (P < 0.05) per mouse significantly enhanced cytotoxic activity; however, live KB392 had no effect. CONCLUSIONS: Both live and heat-killed KB290 and crude EPS-b significantly enhanced cytotoxic activity of mouse splenocytes. SIGNIFICANCE AND IMPACT OF THE STUDY: We demonstrated that EPS-b produced by KB290 has a critical role in enhancing cell-mediated cytotoxic activity in mouse spleen.


Subject(s)
Cytotoxicity, Immunologic , Levilactobacillus brevis , Polysaccharides, Bacterial/pharmacology , Probiotics/pharmacology , Spleen/immunology , Animals , Cytotoxicity, Immunologic/drug effects , Female , Mice, Inbred BALB C , Polysaccharides, Bacterial/chemistry
2.
Osteoporos Int ; 25(4): 1255-66, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24531422

ABSTRACT

UNLABELLED: Embryonic stem cells (ESCs) have become increasingly attractive for cell replacement therapies of osteodegenerative diseases; however, pre-clinical studies in large animal models to repair diseased or injured bone are lacking. As a first step into this direction, we describe here the feeder-free cultivation and directed osteogenic differentiation of marmoset ESCs. INTRODUCTION: Owing to their potential to self-renew and their enormous differentiation capability, ESCs are an adequate cell source for cell replacement therapies. To implement stem cell technology clinically, standardized cultivation and differentiation protocols and appropriate animal models are needed. Here, we describe the feeder-free cultivation of Callithrix jacchus ESCs (cESCs) in a chemically defined medium and their subsequent osteogenic differentiation. METHODS: cESCs were maintained on mouse embryonic fibroblast feeder layers or in feeder-free conditions with activin A and basic fibroblast growth factor. Differentiation into mature osteoblasts was steered with ascorbic acid, ß-glycerophosphate and 1α,25-(OH)2 vitamin D3 employing various induction strategies. RESULTS: In feeder-free conditions, cESCs maintained pluripotency as indicated by Oct-4 and Nanog expression, positive immunostaining for typical primate ESC markers and high telomerase activity. Cells also remained karyotypically normal after 40 passages without feeder cells. The hanging drop protocol as well as omitting the embryoid body step proved unsuccessful to initiate osteogenic differentiation. The highest degree of osteogenesis was achieved by formation of embryoid bodies employing the cell cluster technique as indicated by the amount of deposited calcium and bone marker gene expression. Early addition of retinoic acid further improved the yield of osteoblasts and led to an increase in calcium deposition. CONCLUSIONS: The osteogenic differentiation potential of feeder-free cESCs was equal if not higher compared to cells grown on feeders. These findings open the field for near clinical transplantation studies in primate models to evaluate the effectiveness of ESC-derived osteoblasts.


Subject(s)
Embryonic Stem Cells/cytology , Osteogenesis/physiology , Animals , Callithrix , Cell Culture Techniques/methods , Cell Differentiation/drug effects , Cell Differentiation/genetics , Cell Line , Coculture Techniques , Culture Media/pharmacology , Embryonic Stem Cells/drug effects , Fibroblasts/cytology , Karyotype , Mice , Models, Animal , Osteoblasts/cytology , Osteogenesis/drug effects , Tretinoin/pharmacology
3.
Ir Med J ; 107(3): 87-8, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24757896

ABSTRACT

The Internet provides patients and their families with ready access to on-line health related information. However, this information is not always accurate, understandable or provided by health professionals or advocacy groups. One hundred children with Type 1 diabetes mellitus, or their parents, attending a paediatric diabetes clinic during September to November 2011 were invited sequentially to participate in this questionnaire-based survey of Internet use in searching for diabetes-related information. Sixty-seven (67%) returned completed anonymised questionnaires: 36/67 (53%) were categorised as socio-economic groups C1/C2. Of the 67 families who returned completed questionnaires, 64 (96%) had a home computer and 62 (93%) had home Internet access; 27 (40%) rarely, and 40 (60%) frequently, searched on-line for diabetes-related information. Key search terms were not provided by respondents. There appears to be considerable internet use in seeking health related information for children with Type 1 diabetes mellitus. Clinicians should make efforts to direct patients and their families to websites that present accurate and current information.


Subject(s)
Diabetes Mellitus, Type 1/psychology , Health Literacy , Information Seeking Behavior , Parents , Adolescent , Child , Female , Health Literacy/methods , Health Literacy/standards , Humans , Internet/standards , Male , Parents/education , Parents/psychology , Socioeconomic Factors , Surveys and Questionnaires
4.
Br J Anaesth ; 108(5): 768-75, 2012 May.
Article in English | MEDLINE | ID: mdl-22401881

ABSTRACT

BACKGROUND: The STOP-Bang questionnaire is used to screen patients for obstructive sleep apnoea (OSA). We evaluated the association between STOP-Bang scores and the probability of OSA. METHODS: After Institutional Review Board approval, patients who visited the preoperative clinics for a scheduled inpatient surgery were approached for informed consent. Patients answered STOP questionnaire and underwent either laboratory or portable polysomnography (PSG). PSG recordings were scored manually. The BMI, age, neck circumference, and gender (Bang) were documented. Over 4 yr, 6369 patients were approached and 1312 (20.6%) consented. Of them, 930 completed PSG, and 746 patients with complete data on PSG and STOP-Bang questionnaire were included for data analysis. RESULTS: The median age of 746 patients was 60 yr, 49% males, BMI 30 kg m(-2), and neck circumference 39 cm. OSA was present in 68.4% with 29.9% mild, 20.5% moderate, and 18.0% severe OSA. For a STOP-Bang score of 5, the odds ratio (OR) for moderate/severe and severe OSA was 4.8 and 10.4, respectively. For STOP-Bang 6, the OR for moderate/severe and severe OSA was 6.3 and 11.6, respectively. For STOP-Bang 7 and 8, the OR for moderate/severe and severe OSA was 6.9 and 14.9, respectively. The predicted probabilities for moderate/severe OSA increased from 0.36 to 0.60 as the STOP-Bang score increased from 3 to 7 and 8. CONCLUSIONS: In the surgical population, a STOP-Bang score of 5-8 identified patients with high probability of moderate/severe OSA. The STOP-Bang score can help the healthcare team to stratify patients for unrecognized OSA, practice perioperative precautions, or triage patients for diagnosis and treatment.


Subject(s)
Severity of Illness Index , Sleep Apnea, Obstructive/diagnosis , Aged , Body Mass Index , Female , Humans , Male , Mass Screening/methods , Middle Aged , Neck/pathology , Polysomnography/methods , Predictive Value of Tests , Prospective Studies , Sleep Apnea, Obstructive/pathology
5.
Neuroimage ; 54(4): 2741-9, 2011 Feb 14.
Article in English | MEDLINE | ID: mdl-21044887

ABSTRACT

Advanced magnetic resonance (MR) neuroimaging analysis techniques based on voxel-wise statistics, such as voxel-based morphometry (VBM) and functional MRI, are widely applied to cognitive brain research in both human subjects and in non-human primates. Recent developments in imaging have enabled the evaluation of smaller animal models with sufficient spatial resolution. The common marmoset (Callithrix jacchus), a small New World primate species, has been widely used in neuroscience research, to which voxel-wise statistics could be extended with a species-specific brain template. Here, we report, for the first time, a tissue-segmented, population-averaged standard template of the common marmoset brain. This template was created by using anatomical T(1)-weighted images from 22 adult marmosets with a high-resolution isotropic voxel size of (0.2 mm)(3) at 7-Tesla and DARTEL algorithm in SPM8. Whole brain templates are available at International Neuroinformatics Japan Node website, http://brainatlas.brain.riken.jp/marmoset/.


Subject(s)
Anatomy, Artistic , Atlases as Topic , Brain/anatomy & histology , Callithrix/anatomy & histology , Animals , Female , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male
7.
Kyobu Geka ; 61(10): 903-6, 2008 Sep.
Article in Japanese | MEDLINE | ID: mdl-18788385

ABSTRACT

18-year-old male was referred to our hospital due to persistent cough. The patient was admitted for the investigation of the abnormal shadow on a chest X-ray and chest computed tomography (CT). Chest CT showed a 2.5 cm nodular shadow in the right lower lobe. Bronchofiberscopy revealed the polypoid lesion at the right lower lobe bronchus obstructing the entire lumen of B8-10. The tumor surface was smooth and rich in small vessels. Right lower lobectomy was peformed. The diagnosis of schwannoma was confirmd with the S-100 positive immunohistochemical stain. Bronchial schwannoma is relatively rare disease; less than 90 cases have been reported with respect to schwannoma of case report in Japan.


Subject(s)
Bronchial Neoplasms/diagnosis , Bronchial Neoplasms/surgery , Neurilemmoma/diagnosis , Neurilemmoma/surgery , Adult , Bronchial Neoplasms/pathology , Bronchoscopy , Diagnosis, Differential , Diagnostic Imaging , Humans , Male , Neurilemmoma/pathology , Pneumonectomy , Treatment Outcome
8.
J Comp Pathol ; 156(2-3): 281-285, 2017.
Article in English | MEDLINE | ID: mdl-28161098

ABSTRACT

We describe the development of neurological signs in four juvenile black-and-white ruffed lemurs (Varecia variegate), housed at a petting zoo in Japan. The clinical course was severe, with three lemurs dying within 1 day of the appearance of clinical signs. The other lemur was treated and survived. Pathological analyses demonstrated meningitis and the presence of gram-negative bacilli in the cerebrum, cerebellum, palatine tonsil and liver. Klebsiella pneumoniae was isolated from the brain of all of the dead lemurs. Multilocus sequence typing analysis showed that all the isolates were sequence type 86 (ST86). To our knowledge, this is the first determination of K. pneumoniae infection in ruffed lemurs of this genus. K. pneumoniae infection may represent a risk to lemurs and people who come into contact with infected animals.


Subject(s)
Animals, Zoo/microbiology , Klebsiella Infections/veterinary , Lemur/microbiology , Meningitis, Bacterial/veterinary , Animals , Klebsiella pneumoniae , Male
9.
Drug Res (Stuttg) ; 66(9): 464-469, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27750360

ABSTRACT

Patients with spinal cord injury (SCI) usually develop lower urinary tract dysfunctions, including detrusor overactivity which is also known to be a risk factor for upper urinary tract dysfunction. Antimuscarinic agents, such as propiverine, have been used clinically for the treatment of detrusor overactivity. Also, propiverine has been known to possess antagonistic activity against L-type Ca2+ channels and transient receptor potential vanilloid subtype 1 (TRPV1), in addition to activity against muscarinic receptors. These mechanisms of action may contribute to improving detrusor overactivity in SCI. We therefore investigated the effects of antagonists of these mechanisms on non-voiding contraction (NVC) in SCI rats that are similar to clinical cases of detrusor overactivity, and considered whether these action mechanisms contribute to the incidence of NVC in SCI. Cystometry was performed in rats 4 weeks after spinal transection. Urinary functions were evaluated before and after intravenous administration of propiverine and specific antagonists for muscarinic receptors (atropine), L-type Ca2+ channels (verapamil), and TRPV1 (capsazepine). Propiverine markedly decreased the amplitude pressure of NVC in SCI rats, which was partially inhibited by atropine. Verapamil also suppressed the amplitude pressure of NVC to the same degree as propiverine. NVC disappeared almost completely after C-fiber desensitization, although capsazepine exerted no evident effects. These findings suggest that muscarinic receptors, L-type Ca2+ channels, and C-fiber afferent nerves contribute to the incidence of detrusor overactivity in SCI, and a drug that has multiple antagonistic effects, such as propiverine, is very effective for the treatment of lower urinary tract dysfunctions in SCI.


Subject(s)
Benzilates/antagonists & inhibitors , Spinal Cord Injuries/drug therapy , Urinary Bladder, Overactive/drug therapy , Animals , Atropine/pharmacology , Benzilates/therapeutic use , Capsaicin/analogs & derivatives , Capsaicin/pharmacology , Female , Muscarinic Antagonists/therapeutic use , Rats , Spinal Cord Injuries/complications , Urinary Bladder/drug effects , Urinary Bladder, Overactive/complications , Verapamil/pharmacology
11.
J Phys Chem B ; 120(26): 5945-52, 2016 07 07.
Article in English | MEDLINE | ID: mdl-27187612

ABSTRACT

Self-assembling protein nanocontainers are promising candidates for an increasingly wide scope of purposes. Their applications range from drug delivery vehicles and imaging agents to nanocompartments for controlled enzymatic activity. In order to exploit their full potential in these different fields, characterization of their properties is vital. For example, their mechanical properties give insight into the stability of a particle as a function of their internal content. The mechanics can be probed by atomic force microscopy nanoindentation, and while this single particle method is increasingly used to probe material properties of viral nanocages, it has hardly been used to characterize nonviral nanocages. Here we report nanoindentation studies on two types of nonviral nanocontainers: (i) lumazine synthase from Aquifex aeolicus (AaLS), which naturally self-assembles into icosahedral cages, and (ii) the artificial protein cage O3-33 originating from a computational design approach. In addition, we tested particles that had been engineered toward improved cargo loading capacity and compared these nanocages in empty and loaded states. We found that the thermostable AaLS cages are stiffer and resist higher forces before breaking than the O3-33 particles, but that mutations affecting the size of AaLS particles have a dramatic effect on their structural stability. Furthermore, we show that cargo packaging can occur while maintaining the cage's mechanical properties.


Subject(s)
Bacterial Proteins/chemistry , Multienzyme Complexes/chemistry , Nanostructures/chemistry , Bacteria/chemistry , Bacterial Proteins/genetics , Biomechanical Phenomena , Cloning, Molecular , Gene Expression , Microscopy, Atomic Force , Multienzyme Complexes/genetics , Nanostructures/ultrastructure , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Engineering , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Thermodynamics
12.
Sci Rep ; 6: 31084, 2016 08 08.
Article in English | MEDLINE | ID: mdl-27498966

ABSTRACT

Complex motor skills of eventual benefit can be learned after considerable trial and error. What do structural brain changes that accompany such effortful long-term learning tell us about the mechanisms for developing innovative behavior? Using MRI, we monitored brain structure before, during and after four marmosets learnt to use a rake, over a long period of 10-13 months. Throughout learning, improvements in dexterity and visuo-motor co-ordination correlated with increased volume in the lateral extrastriate cortex. During late learning, when the most complex behavior was maintained by sustained motivation to acquire the skill, the volume of the nucleus accumbens increased. These findings reflect the motivational state required to learn, and show accelerated function in higher visual cortex that is consistent with neurocognitive divergence across a spectrum of primate species.


Subject(s)
Learning , Motor Cortex/anatomy & histology , Motor Skills , Animals , Callithrix , Female , Gray Matter/anatomy & histology , Gray Matter/diagnostic imaging , Gray Matter/physiology , Magnetic Resonance Imaging , Motor Cortex/diagnostic imaging , Motor Cortex/physiology , Nucleus Accumbens/anatomy & histology , Nucleus Accumbens/diagnostic imaging , Nucleus Accumbens/physiology , Psychomotor Performance , Tool Use Behavior , Visual Cortex/anatomy & histology , Visual Cortex/diagnostic imaging , Visual Cortex/physiology
13.
Biochim Biophys Acta ; 1259(3): 297-304, 1995 Dec 07.
Article in English | MEDLINE | ID: mdl-8541338

ABSTRACT

Lymphatic transport of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids given as trieicosapentaenoyl glycerol (TriEPA) and tridocosahexaenoyl glycerol (TriDHA) was compared with that of ethyl ester and free acid in rats cannulated with thoracic duct. Trioleoylglycerol (TO) served as a control. EPA and DHA, compared with oleic acid, were slowly transported in lymph irrespective of fat types administered. Total 24-h recovery of DHA in all fat types and ethyl EPA was significantly lower compared to that of oleic acid. Lymphatic recovery of EPA and DHA in rats given TriEPA and TriDHA was significantly higher at the first 3 h after the administration compared to those given as free acid or ethyl ester. The recovery in rats given free acid at a later stage (9-24 h) was higher than that of the other fat types. As a result, the 24-h recovery was comparable between triacylglycerol (TAG) and free acid, while it was significantly lower in ethyl ester. Although TriEPA and TriDHA were slowly hydrolyzed by pancreatic lipase in vitro compared with TO and TAGs rich in EPA or DHA at the second position, the hydrolysis rate at 60 min incubation was comparable among the TAGs examined. The hydrolysis rate of ethyl esters was extremely low even in 6 h incubation with lipase. These observations show that presence of EPA and DHA at the 1- and 3-positions of TAGs does not result in their lower recovery in lymph. Processes after lipolysis may be responsible for their low recovery in lymph. In a separate study, slower lymphatic recovery of DHA given as free acid than TriDHA was improved by the simultaneous administration of TO, but not by free oleic acid. The observations suggest that the slow recovery of free acid is caused by delayed TAG synthesis in mucosal cells and/or low micellar solubility of fatty acids in the intestinal lumen due to a limited supply of 2-monoacylglycerol (MAG). A large portion of EPA and DHA were recovered in lymph chylomicrons and very low density lipoproteins (VLDL, > 95%) and incorporated into TAG (84-92%) fraction in all fat types examined. Lymphatic recovery rate of simultaneously administered cholesterol was influenced by the fat types given.


Subject(s)
Docosahexaenoic Acids/metabolism , Eicosapentaenoic Acid/metabolism , Lymph/chemistry , Lymph/metabolism , Animals , Body Weight , Chylomicrons/metabolism , Esters/metabolism , Intestinal Absorption/physiology , Lipase/metabolism , Lymphatic System/metabolism , Oleic Acid , Oleic Acids/metabolism , Oleic Acids/pharmacology , Phospholipids/metabolism , Rats , Triglycerides/metabolism , Triolein/metabolism , Triolein/pharmacology
14.
Biochim Biophys Acta ; 1127(2): 141-6, 1992 Jul 29.
Article in English | MEDLINE | ID: mdl-1643098

ABSTRACT

A(-)-epicatechin (EC) and (-)-epigallocatechin (EGC) mixture and a mixture of their gallates (ECG and EGCG, respectively) markedly lowered lymphatic cholesterol absorption in rats with a cannulated thoracic duct. A mixture of ECG and EGCG was more effective in reducing cholesterol absorption than the EC and EGC mixture. These catechins also tended to decrease lymphatic absorption of triacylglycerols, although not so pronounced as in cholesterol absorption. An in vitro study on micellar solubility of cholesterol showed that these catechin mixtures precipitated cholesterol solubilized in mixed bile salt micelles in a dose-dependent manner. A mixture of ECG and EGCG more effectively precipitated micellar cholesterol than a mixture of EC and EGC. When purified EC, EGC, ECG and EGCG were used, EGCG was more effective in precipitating micellar cholesterol than ECG. The effect of EC and EGC was comparable and weaker than their gallate esters. The bile acid concentration in the micelles was not affected by these catechins. A positive correlation was observed between the amount of coprecipitated EGCG and cholesterol. These results clearly show that tea catechins, in particular their gallate esters, effectively reduce cholesterol absorption from the intestine by reducing solubility of cholesterol in mixed micelles. The observation accounts for the hypocholesterolemic effect of tea catechins.


Subject(s)
Catechin/pharmacology , Cholesterol/metabolism , Intestinal Absorption/drug effects , Tea , Animals , Bile Acids and Salts/metabolism , Catechin/analogs & derivatives , Flavonoids/pharmacology , Male , Micelles , Rats , Rats, Inbred Strains , Solubility , Triglycerides/metabolism
15.
J Clin Endocrinol Metab ; 59(2): 303-9, 1984 Aug.
Article in English | MEDLINE | ID: mdl-6330155

ABSTRACT

To determine factors mediating the aldosterone secretory response to orthostasis, we examined the effect of angiotensin-converting enzyme inhibition (CEI) on orthostasis in eight normal subjects and 10 normotensive patients with primary glomerulonephritis ingesting a normal sodium intake. On standing with CEI, the mean plasma aldosterone concentration (PAC) did not change [68.6 +/- 3.9 (+/- SE) and 63.4 +/- 6.9 pg/ml] in normal subjects, while PAC rose significantly from 72.3 +/- 7.5 to 129.5 +/- 13.2 pg/ml (P less than 0.001) in the glomerulonephritis patients without a concurrent rise in plasma angiotensin II, serum potassium, plasma ACTH, or mean blood pressure. There was a good correlation (r = -0.7064; P less than 0.03) between the changes in PAC and the changes in fractional sodium excretion in the patients. Pretreatment with indomethacin blunted the rise in PAC from 159.0 +/- 21.5 to 63.3 +/- 10.2 pg/ml upon standing with CEI, without a concurrent change in circulating 6-keto prostaglandin F1 alpha (from 57.7 +/- 9.5 to 56.0 +/- 11.1 pg/ml) in 4 patients. These results suggest that the aldosterone secretory response to orthostasis in patients with glomerulonephritis is dependent on factors blunted by pretreatment with indomethacin in addition to angiotensin II.


Subject(s)
Aldosterone/blood , Glomerulonephritis/blood , Indomethacin/pharmacology , 6-Ketoprostaglandin F1 alpha/blood , Adrenocorticotropic Hormone/blood , Adult , Angiotensin II/blood , Glomerulonephritis/physiopathology , Humans , Male , Posture , Potassium/blood , Renin/blood
16.
Gene ; 141(2): 305-6, 1994 Apr 20.
Article in English | MEDLINE | ID: mdl-7512939

ABSTRACT

The Kit protein is a cell-surface tyrosine kinase receptor encoded by the c-kit proto-oncogene. cDNA clones encoding a protein homologous to the mouse and human Kit were isolated from a bovine cerebrum cDNA library. The deduced amino-acid sequence shows 83 and 90% identity to the mouse and human Kit, respectively.


Subject(s)
Proto-Oncogene Proteins/genetics , Receptor Protein-Tyrosine Kinases/genetics , Receptors, Colony-Stimulating Factor/genetics , Amino Acid Sequence , Animals , Base Sequence , Cattle , Humans , Mice , Molecular Sequence Data , Proto-Oncogene Mas , Proto-Oncogene Proteins c-kit , Sequence Homology, Amino Acid
17.
Gene ; 128(2): 257-61, 1993 Jun 30.
Article in English | MEDLINE | ID: mdl-7685729

ABSTRACT

The Kit protein is a cell-surface tyrosine kinase receptor encoded by the c-kit proto-oncogene. cDNA clones encoding chicken Kit were isolated from a chicken brain cDNA library, and the nucleotide (nt) sequence of a cDNA clone containing the entire protein-coding region was determined. The deduced amino acid (aa) sequence of chicken Kit shows 63% identity to mouse Kit, and suggests that chicken Kit shares common structural and functional features with mouse Kit. RNA blot analysis indicated that the expression pattern of the chicken c-kit transcript in chicken organs was similar to that of mouse c-kit in mice, suggesting that chicken Kit has biological roles analogous to those of mouse Kit.


Subject(s)
Chickens/genetics , Protein-Tyrosine Kinases/genetics , Proto-Oncogene Proteins/genetics , Receptors, Colony-Stimulating Factor/genetics , Amino Acid Sequence , Animals , Base Sequence , Brain Chemistry/genetics , Cloning, Molecular , Gene Expression , Male , Mice , Molecular Sequence Data , Proto-Oncogene Proteins c-kit , RNA, Messenger/analysis , Sequence Homology, Amino Acid , Testis/chemistry
18.
Transplantation ; 63(5): 705-10, 1997 Mar 15.
Article in English | MEDLINE | ID: mdl-9075842

ABSTRACT

Alloantigens are recognized by T cells either through a direct pathway, which involves recognition of alloantigens expressed on allogeneic antigen-presenting cells (APC), or through an indirect pathway, which involves recognition of processed alloantigens presented by self APC. We investigated whether rat xenoantigens are also recognized by direct (xenogeneic APC-restricted) and/or indirect (self APC-restricted) pathways. C57BL/6 (B6) mouse anti-F344 or WKAH rat mixed lymphocyte reactions (MLRs) were partially inhibited by addition of either anti-mouse CD4 or CD8 monoclonal antibody (mAb) and almost completely blocked in the presence of both mAbs. These xenogeneic MLRs were almost completely inhibited by simultaneous depletion of both self and xeno APCs and only partially suppressed by the elimination of either type of APC, indicating that freshly prepared splenic mouse T cells can recognize rat xenoantigens through both direct and indirect pathways. Anti-F334 T cell lines were generated from B6 anti-F344 MLR cultures, and four CD4+ and four CD8+ T cell clones were isolated from these parental lines. The parental lines and those derived T cell clones were tested for their ability to proliferate depending on the presence of F344 APC. Proliferation of CD8 clones by stimulation with F344 APC was inhibited by the addition of anti-rat class I MHC mAb but not of anti-class II MHC mAbs. Conversely, proliferation of CD4 clones was reduced by addition of anti-class II MHC mAbs. Thus, these results indicate that xeno (rat)-reactive mouse T cells recognize xenoantigens via both indirect (self APC-restricted) and direct (xeno APC-restricted) pathways and that both CD4 and CD8 subsets of T cells participate in a direct pathway of xenoantigen recognition.


Subject(s)
Antigen-Presenting Cells/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Histocompatibility Antigens/immunology , Animals , Antigens, Heterophile/immunology , Cell Division , Clone Cells , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Phenotype , Rats , Rats, Inbred F344
19.
Thromb Haemost ; 77(6): 1148-53, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9241748

ABSTRACT

We studied the use of depolymerized holothurian glycosaminoglycan (DHG) as an anticoagulant in experimental beagle-dog hemodialysis using a hollow-fiber dialyzer compared to that using unfractionated heparin (UFH), low-molecular-weight heparin (LMWH), and nafamostat mesilate (FUT). Effectiveness was based on 5 h hemodialysis and no marked clot deposition in the extracorporeal circuit. At effective doses, UFH and LMWH significantly prolonged template bleeding time, in sharp contrast to FUT and DHG, which scarcely prolonged bleeding time during hemodialysis. DHG prolonged activated partial thromboplastin time (APTT) about 6 times that of normal plasma and prolonged thrombin clotting time (TCT) markedly; FUT showed marked APTT prolongation but hardly prolonged TCT in the hemodialysis circuit at the effective dose. The anticoagulant profile of DHG thus differs completely from that of FUT. These results suggest that DHG may be useful as anticoagulant for hemodialysis with low hemorrhagic risk.


Subject(s)
Anticoagulants/administration & dosage , Glycosaminoglycans/administration & dosage , Renal Dialysis , Animals , Dogs , Heparin/administration & dosage , Heparin, Low-Molecular-Weight/administration & dosage
20.
Thromb Haemost ; 77(2): 399-402, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9157603

ABSTRACT

A previous study in this laboratory showed that depolymerized holothurian glycosaminoglycan (DHG) has two different antithrombin III (ATIII)-independent inhibitory effects on the in vitro blood coagulation system: heparin cofactor II (HCII)-dependent inhibition of thrombin, and ATIII- and HCII-independent inhibition of factor X activation by factor IXa-factor VIIIa complex (Nagase et al. Blood 85, 1527-1534, 1995). In the present study, we compared the antithrombotic effects of DHG in normal and in ATIII-deficient mice with those of unfractionated heparin (UFH) and low molecular weight heparin (LMWH). DHG, unlike UFH and LMWH, exerted an in vivo antithrombotic effect even in mice with decreased plasma ATIII activity (about 30% of normal). We then compared the anticoagulant and antithrombotic effects of DHG in mice with those of high molecular weight (HMW)-DHG, low molecular weight (LMW)-DHG, and dermatan sulfate (DS). In terms of in vitro anticoagulant activity assessed by use of purified human components, DHGs (DHG, HMW-DHG, and LMW-DHG) had different anti-thrombin activity in the presence of HCII and anti-factor Xase activities, which differences were dependent on the molecular weight. With respect to in vivo antithrombotic activity, DHG, HMW-DHG, and LMW-DHG showed almost the same inhibitory effect on acute thromboembolism in mice (minimum effective dose [MED]: > 0.3 mg/kg). Since the antithrombotic activities of DHGs were not correlated with the anticoagulant-specific activities, the contribution of the two anticoagulant activities to the in vivo antithrombotic effect of DHGs remains unknown. However, DHG was more effective against acute thromboembolism in mice than DS (MED > 1 or > 3 mg/kg), which showed no inhibitory activity toward factor Xase. Therefore, it seems that factor Xase inhibition contributes greatly to the antithrombotic effect of DHG and that DHG exerts this effect in mice mainly by inhibiting factor Xase.


Subject(s)
Antithrombin III/physiology , Fibrinolytic Agents/therapeutic use , Glycosaminoglycans/therapeutic use , Sea Cucumbers/chemistry , Thromboembolism/drug therapy , Thrombolytic Therapy , Animals , Antithrombin III Deficiency , Cattle , Fibrinolytic Agents/chemistry , Fibrinolytic Agents/isolation & purification , Glycosaminoglycans/chemistry , Glycosaminoglycans/isolation & purification , Male , Mice , Mice, Inbred ICR , Thrombin/toxicity , Thromboembolism/chemically induced
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