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1.
Science ; 375(6576): eabg7277, 2022 Jan 07.
Article in English | MEDLINE | ID: mdl-34990249

ABSTRACT

Acting to achieve goals depends on the ability to motivate specific behaviors based on their predicted consequences given an individual's internal state. However, the underlying neuronal mechanisms that encode and maintain such specific motivational control of behavior are poorly understood. Here, we used Ca2+ imaging and optogenetic manipulations in the basolateral amygdala of freely moving mice performing noncued, self-paced instrumental goal-directed actions to receive and consume rewards. We found that distinct neuronal activity patterns sequentially represent the entire action-consumption behavioral sequence. Whereas action-associated patterns integrated the identity, value, and expectancy of pursued goals, consumption-associated patterns reflected the identity and value of experienced outcomes. Thus, the interplay between these patterns allows the maintenance of specific motivational states necessary to adaptively direct behavior toward prospective rewards.


Subject(s)
Basolateral Nuclear Complex/physiology , Behavior, Animal , Motivation , Neurons/physiology , Animals , Calcium/analysis , Goals , Male , Mice , Reward
3.
Scand J Rheumatol ; 42(4): 253-9, 2013.
Article in English | MEDLINE | ID: mdl-23470089

ABSTRACT

OBJECTIVES: The retention of the anti-rheumatic agent tocilizumab (TCZ) has not been well documented in patients with rheumatoid arthritis (RA). We conducted an observational study to compare the retention of TCZ and anti-tumour necrosis factor (TNF) drugs in the treatment of patients with RA. METHOD: We reviewed continuation rates and causes of discontinuation of biological agents (biologics) by assessing medical records of patients with RA who were administered biologics at our institute from September 1999 to April 2012, using the Osaka University Biologics for Rheumatic Diseases (BiRD) registry. RESULTS: A total of 401 patients were included. TCZ, infliximab (IFX), etanercept (ETN), and adalimumab (ADA) were administered to 97, 103, 143, and 58 patients, respectively. There were some differences between the baseline characteristics of the groups. The median duration (range) of TCZ, IFX, ETN, and ADA administration was 2.5 (0.1-12.6), 1.9 (0.0-7.7), 2.9 (0.0-11.3), and 1.3 (0.0-3.4) years, respectively. Continuation rates for TCZ and ETN were significantly higher than those for IFX and ADA. Multivariate analyses showed that discontinuation due to lack or loss of efficacy was significantly less common in the TCZ group than in the other groups. Discontinuation due to overall adverse events was not significantly different between treatment groups. CONCLUSION: TCZ and ETN show better retention than IFX or ADA in the treatment of RA.


Subject(s)
Antibodies, Monoclonal, Humanized/pharmacokinetics , Antibodies, Monoclonal/pharmacokinetics , Arthritis, Rheumatoid/drug therapy , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adalimumab , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal, Humanized/administration & dosage , Arthritis, Rheumatoid/diagnosis , Cohort Studies , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Follow-Up Studies , Humans , Infliximab , Kaplan-Meier Estimate , Male , Middle Aged , Proportional Hazards Models , Retrospective Studies , Risk Assessment , Severity of Illness Index , Treatment Outcome , Young Adult
4.
Bone Marrow Transplant ; 48(4): 581-6, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23528643

ABSTRACT

Chronic impairment of cardiac function can be an important health risk and impair the quality of life, and may even be life-threatening for long-term survivors of allogeneic hematopoietic cell transplantation (HCT). However, risk factors for and/or the underlying mechanism of cardiac dysfunction in the chronic phase of HCT are still not fully understood. We retrospectively investigated factors affecting cardiac function and left-ventricular hypertrophy (LVH) in the chronic phase of HCT. Sixty-three recipients who survived for >1 year after receiving HCT were evaluated using echocardiography. Based on simple linear regression models, high-dose TBI-based conditioning was significantly associated with a decrease in left-ventricular ejection fraction and the early peak flow velocity/atrial peak flow velocity ratio, following HCT (coefficient=-5.550, P=0.02 and coefficient=-0.268, P=0.02, respectively). These associations remained significant with the use of multiple linear regression models. Additionally, the serum ferritin (s-ferritin) level before HCT was found to be a significant risk factor for LVH on multivariable logistic analysis (P=0.03). In conclusion, our study demonstrated that a myeloablative regimen, especially one that involved high-dose TBI, impaired cardiac function, and that a high s-ferritin level might be associated with the development of LVH in the chronic phase of HCT.


Subject(s)
Hematopoietic Stem Cell Transplantation/adverse effects , Hypertrophy, Left Ventricular , Models, Biological , Postoperative Complications , Transplantation Conditioning/adverse effects , Ventricular Function, Left , Adolescent , Adult , Aged , Chronic Disease , Echocardiography , Female , Hematologic Neoplasms/diagnostic imaging , Hematologic Neoplasms/physiopathology , Hematologic Neoplasms/therapy , Humans , Hypertrophy, Left Ventricular/diagnostic imaging , Hypertrophy, Left Ventricular/etiology , Hypertrophy, Left Ventricular/physiopathology , Linear Models , Male , Middle Aged , Postoperative Complications/diagnostic imaging , Postoperative Complications/etiology , Postoperative Complications/physiopathology , Retrospective Studies , Risk Factors , Time Factors , Transplantation, Homologous
5.
J Mech Behav Biomed Mater ; 14: 48-54, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22963746

ABSTRACT

The elastic anisotropy of the Ti-15Mo-5Zr-3Al (mass%) ß-Ti alloy, an ISO certified biomedical material, was investigated using its single crystal. It was revealed that the Young's modulus exhibited pronounced anisotropy. The Young's modulus was reduced to 44.4GPa along the 〈100〉 direction in the Ti-15Mo-5Zr-3Al single crystal, that is comparable to that of human cortical bones. We determined the strategy that ß-Ti alloys with extremely low moduli can be developed by reducing the electron-atom (e/a) ratio in alloys, and by suppressing the formation of the ω-phase at the same time. This new knowledge must lead to the development of "single crystalline ß-Ti implant materials" as hard tissue replacements for reducing the stress shielding effect.


Subject(s)
Alloys/chemistry , Aluminum/chemistry , Biocompatible Materials/chemistry , Elastic Modulus , Molybdenum/chemistry , Titanium/chemistry , Zirconium/chemistry , Anisotropy , Crystallography , Stress, Mechanical
6.
Transplant Proc ; 43(10): 3927-32, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22172874

ABSTRACT

Reports on the efficacy of intravenous immunoglobulin (IVIG) prophylaxis against cytomegalovirus (CMV) infection after allogeneic hematopoietic cell transplantation (HCT) have often sparked controversy. In addition, we are not aware of any study that has examined whether prophylaxis with IVIG affects the incidence of CMV infection in high-risk patients--those who are elderly or have received human leukocyte antigen (HLA) mismatched HCT. In the present open-label, phase II study, we addressed this question. We enrolled 106 patients in the study. The cumulative incidences of CMV infection at 100 days after HCT were similar in the intervention and the control groups (68% and 64%, P=.89; 89% and 87%, P=.79, respectively, for patients 55 years or older and those who received HLA-mismatched HCT). In those who received HLA-mismatched HCT, 1-year overall survival after HCT was 46% in the intervention group and 40% in the control group (P=.31); for age≥55 years, the corresponding values were 46% and 40% (P=.27). Our data showed that prophylaxis with regular polyvalent IVIG did not affect the incidence of CMV infections or survival among older patients or those who receive HLA-mismatched HCT.


Subject(s)
Cytomegalovirus Infections/prevention & control , Hematopoietic Stem Cell Transplantation/adverse effects , Immunoglobulins, Intravenous/administration & dosage , Immunologic Factors/administration & dosage , Adolescent , Adult , Age Factors , Aged , Analysis of Variance , Chi-Square Distribution , Cytomegalovirus Infections/immunology , Cytomegalovirus Infections/mortality , Cytomegalovirus Infections/virology , Female , HLA Antigens/immunology , Hematopoietic Stem Cell Transplantation/mortality , Histocompatibility , Humans , Incidence , Japan , Male , Middle Aged , Risk Assessment , Risk Factors , Survival Analysis , Time Factors , Treatment Outcome , Young Adult
7.
Xenobiotica ; 39(11): 836-43, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19845434

ABSTRACT

Mechanism-based inhibition of CYP2C19 in human liver microsomes by the thienopyridine antiplatelet agents clopidogrel, prasugrel and their thiolactone metabolites was investigated by determining the time- and concentration-dependent inhibition of the activity of S-mephenytoin 4'-hydroxylase as typical CYP2C19 activity and compared with ticlopidine and its metabolite. Clopidogrel was shown to be a mechanism-based inhibitor of CYP2C19 with the inactivation kinetic parameters, k(inact) and K(I), equal to 0.0557 min(-1) and 14.3 microM, respectively, as well as ticlopidine (0.0739 min(-1) and 3.32 microM, respectively). The thiolactone metabolite of ticlopidine and clopidogrel inhibited CYP2C19 only in a concentration-dependent manner. In contrast, neither prasugrel nor its thiolactone metabolite inhibited CYP2C19 at concentrations up to 100 microM. The oxidation of the thiophene moiety of clopidogrel to form their respective thiolactones was found to be the critical reaction that produces the chemically reactive metabolites which cause the mechanism-based inhibition of CYP2C19. Estimation of in vivo drug-drug interaction using in vitro parameters predicted clinically observed data. For clopidogrel, there was no increase in the area under the curve (AUC) at its clinical dose level as predicted by the in vitro parameters, and for ticlopidine the prediction agreed with the clinically observed AUC increase. In conclusion, clopidogrel is potent mechanism-based inhibitors of CYP2C19 as well as ticlopidine, whereas prasugrel did not inactivate CYP2C19. Administration of prasugrel would not cause a clinically relevant interaction with CYP2C19.


Subject(s)
Aryl Hydrocarbon Hydroxylases/antagonists & inhibitors , Piperazines/pharmacology , Platelet Aggregation Inhibitors/pharmacology , Thiophenes/pharmacology , Ticlopidine/analogs & derivatives , Ticlopidine/pharmacology , Aryl Hydrocarbon Hydroxylases/pharmacokinetics , Clopidogrel , Cytochrome P-450 CYP2C19 , Humans , Kinetics , Microsomes, Liver/drug effects , Microsomes, Liver/enzymology , Piperazines/chemistry , Platelet Aggregation Inhibitors/chemistry , Prasugrel Hydrochloride , Thiophenes/chemistry , Ticlopidine/chemistry
9.
Xenobiotica ; 39(3): 218-26, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19280520

ABSTRACT

Prasugrel and clopidogrel are antiplatelet prodrugs that are converted to their respective active metabolites through thiolactone intermediates. Prasugrel is rapidly hydrolysed by esterases to its thiolactone intermediate, while clopidogrel is oxidized by cytochrome P450 (CYP) isoforms to its thiolactone. The conversion of both thiolactones to the active metabolites is CYP mediated. This study compared the efficiency, in vivo, of the formation of prasugrel and clopidogrel thiolactones and their active metabolites. The areas under the plasma concentration versus time curve (AUC) of the thiolactone intermediates in the portal vein plasma after an oral dose of prasugrel (1 mg kg(-1)) and clopidogrel (0.77 mg kg(-1)) were 15.8 +/- 15.9 ng h ml(-1) and 0.113 +/- 0.226 ng h ml(-1), respectively, in rats, and 454 +/- 104 ng h ml(-1) and 23.3 +/- 4.3 ng h ml(-1), respectively, in dogs, indicating efficient hydrolysis of prasugrel and little metabolism of clopidogrel to their thiolactones in the intestine. The relative bioavailability of the active metabolites of prasugrel and clopidogrel calculated by the ratio of active metabolite AUC (prodrug oral administration/active metabolite intravenous administration) were 25% and 7%, respectively, in rats, and 25% and 10%, respectively, in dogs. Single intraduodenal administration of prasugrel showed complete conversion of prasugrel, resulting in high concentrations of the thiolactone and active metabolite of prasugrel in rat portal vein plasma, which demonstrates that these products are generated in the intestine during the absorption process. In conclusion, the extent of in vivo formation of the thiolactone and the active metabolite of prasugrel was greater than for clopidogrel's thiolactone and active metabolite.


Subject(s)
Piperazines/metabolism , Platelet Aggregation Inhibitors/metabolism , Thiophenes/metabolism , Ticlopidine/analogs & derivatives , Animals , Area Under Curve , Clopidogrel , Cytochrome P-450 Enzyme System/metabolism , Dogs , Hydrolysis , Male , Molecular Structure , Oxidation-Reduction , Piperazines/blood , Piperazines/chemistry , Piperazines/pharmacokinetics , Piperazines/pharmacology , Platelet Aggregation Inhibitors/pharmacology , Prasugrel Hydrochloride , Rats , Rats, Sprague-Dawley , Thiophenes/blood , Thiophenes/chemistry , Thiophenes/pharmacokinetics , Thiophenes/pharmacology , Ticlopidine/chemistry , Ticlopidine/metabolism , Ticlopidine/pharmacology
11.
Rheumatology (Oxford) ; 47(7): 1018-24, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18440998

ABSTRACT

OBJECTIVES: No objective method to measure skin involvement in SSc has been established. We developed a novel method using a computer-linked device to simultaneously quantify physical properties of the skin such as hardness, elasticity and viscosity. METHODS: Skin hardness was calculated by measuring the depth of an indenter pressed onto the skin. The Voigt model was used to calculate skin elasticity, viscosity, visco-elastic ratio and relaxation time by analysing the waveform of skin surface behaviour. The results were compared with the modified Rodnan skin score (mRSS) obtained at 17 sites on the bodies of 20 SSc patients and 20 healthy controls. A functional assessment questionnaire was administered to determine how skin hardness represents a patient's disability. We also examined intra- and inter-observer variability to determine the reliability of this method. RESULTS: The crude hardness obtained with this device correlated well with the standard hardness specified by the American Society for Testing and Materials (ASTM, r = 0.957). A close relationship between hardness and total mRSS was also observed (r = 0.832). Skin elasticity correlated positively, and relaxation time negatively with mRSS. Functional disability correlated more closely with skin hardness (r = 0.643) than with mRSS (r = 0.517). Intra- and inter-observer variabilities were 7.63 and 19.76%, respectively, which were lower than those reported for mRSS. CONCLUSIONS: Increases in hardness and elasticity as well as shortening of relaxation time constitute objective characteristics of skin involvement in SSc. The system devised by us proved to be able to assess skin abnormalities of SSc with high reliability.


Subject(s)
Scleroderma, Systemic/physiopathology , Skin/physiopathology , Adult , Aged , Elasticity , Female , Hardness , Hardness Tests/instrumentation , Hardness Tests/methods , Humans , Male , Middle Aged , Observer Variation , Severity of Illness Index , Signal Processing, Computer-Assisted , Viscosity
12.
Xenobiotica ; 37(7): 788-801, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17620223

ABSTRACT

Prasugrel is converted to the pharmacologically active metabolite after oral dosing in vivo. In this study, (14)C-prasugrel or prasugrel was administered to rats at a dose of 5 mg kg(-1). After oral and intravenous dosing, the values of AUC(0-infinity) of total radioactivity were 36.2 and 47.1 microg eqx h ml(-1), respectively. Oral dosing of unlabeled prasugrel showed the second highest AUC(0-8) of the active metabolite of six metabolites analyzed. Quantitative whole body autoradiography showed high radioactivity concentrations in tissues for absorption and excretion at 1 h after oral administration, and were low at 72 h. The excretion of radioactivity in the urine and feces were 20.2% and 78.7%, respectively, after oral dosing. Most radioactivity after oral dosing was excreted in bile (90.1%), which was reabsorbed moderately (62.4%). The results showed that orally administered prasugrel was rapidly and fully absorbed and efficiently converted to the active metabolite with no marked distribution in a particular tissue.


Subject(s)
Intestinal Absorption , Piperazines/pharmacokinetics , Purinergic P2 Receptor Antagonists , Pyridines/pharmacokinetics , Thiophenes/pharmacokinetics , Animals , Carbon Radioisotopes , Male , Prasugrel Hydrochloride , Rats , Rats, Inbred F344
13.
J Thromb Haemost ; 5(7): 1545-51, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17456192

ABSTRACT

BACKGROUND AND METHODS: Prasugrel is a novel orally active thienopyridine prodrug with potent and long-lasting antiplatelet effects. Platelet inhibition reflects inhibition of P2Y(12) receptors by its active metabolite (AM). Previous studies have shown that the antiplatelet potency of prasugrel is at least 10 times higher than that of clopidogrel in rats and humans, but the mechanism of its higher potency has not yet been fully elucidated. RESULTS: Oral administration of prasugrel to rats resulted in dose-related and time-related inhibition of ex vivo platelet aggregation, and its effect was about 10 times more potent than that of clopidogrel. The plasma concentration of prasugrel AM was higher than that of clopidogrel AM despite tenfold higher doses of clopidogrel, indicating more efficient in vivo production of prasugrel AM than of clopidogrel AM. In rat platelets, prasugrel AM inhibited in vitro platelet aggregation induced by adenosine 5'-diphosphate (ADP) (10 microm) with an IC(50) value of 1.8 microm. Clopidogrel AM similarly inhibited platelet aggregation with an IC(50) value of 2.4 microm. Similar results were also observed for ADP-induced (10 microm) decreases in prostaglandin E(1)-stimulated rat platelet cAMP levels. These results indicate that both AMs have similar in vitro antiplatelet activities. CONCLUSIONS: The greater in vivo antiplatelet potency of prasugrel as compared to clopidogrel reflects more efficient in vivo generation of its AM, which demonstrates similar in vitro activity to clopidogrel AM.


Subject(s)
Blood Platelets/drug effects , Blood Platelets/metabolism , Piperazines/blood , Piperazines/pharmacology , Platelet Aggregation Inhibitors/blood , Platelet Aggregation Inhibitors/pharmacology , Thiophenes/blood , Thiophenes/pharmacology , Ticlopidine/analogs & derivatives , Adenosine Diphosphate/pharmacology , Alprostadil/pharmacology , Animals , Clopidogrel , Cyclic AMP/blood , Dose-Response Relationship, Drug , Humans , In Vitro Techniques , Male , Piperazines/administration & dosage , Platelet Aggregation/drug effects , Platelet Aggregation Inhibitors/administration & dosage , Prasugrel Hydrochloride , Rats , Rats, Sprague-Dawley , Thiophenes/administration & dosage , Ticlopidine/administration & dosage , Ticlopidine/blood , Ticlopidine/pharmacology
14.
Arch Virol ; 150(10): 1977-91, 2005 Oct.
Article in English | MEDLINE | ID: mdl-15959837

ABSTRACT

The effect of hexamethylane bisacetamide (HMBA), a hybrid polar compound, on gene expression and replication of human cytomegalovirus (HCMV) was studied. When HCMV-infected human thyroid papillary carcinoma (TPC-1) and human embryonic lung (HEL) fibroblast cells were maintained with medium containing 2.5 and 5 mM HMBA for 10 days, there was a greater than 2- to 3-log reduction in virus yield compared to that in untreated cells. Infection of TPC-1 cells with HCMV resulted in an establishment of persistent infection and the cells continuously produced virus with titer of over 10(5) PFU/ml, whereas HMBA prevented the infected cells from entering into the persistent infection. Moreover, treatment of the persistently infected cultures with HMBA reduced production of infectious HCMV more efficiently than did ganciclovir, and eventually ceased HCMV production. Western blotting analysis revealed that HMBA blocks accumulation of the immediate early 2 (IE2) protein in TPC-1 cells and delays synthesis of this protein in HEL cells, but has little effect on the level of the IE1 protein during the early times after infection. Synthesis of the viral early and late proteins in both cells was also substantially blocked by HMBA. The results indicate that the inhibition or the delay of the critical IE2 protein synthesis in the presence of HMBA would actually be a process that fails to proceed beyond the IE stages in HCMV replication cycle.


Subject(s)
Acetamides/pharmacology , Antiviral Agents/pharmacology , Cytomegalovirus/drug effects , Cytomegalovirus/physiology , Virus Replication/drug effects , Antigens, Viral/biosynthesis , Cell Division/drug effects , Cell Line , Cytomegalovirus/immunology , Ganciclovir/pharmacology , Humans , Immediate-Early Proteins/biosynthesis , Trans-Activators/biosynthesis , Viral Proteins/biosynthesis
15.
Bone Marrow Transplant ; 33(6): 661-5, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14716337

ABSTRACT

This article describes the first case of acute myeloid leukemia (AML) in a healthy donor at 14 months after granulocyte colony-stimulating factor (G-CSF)-primed peripheral blood stem cell (PBSC) harvest. In September 2001, a healthy 61-year-old female was given G-CSF prior to PBSC harvest for her brother with multiple myeloma. In spite of successful engraftment, the recipient died from a disease relapse. In November 2002, the donor, admitted with high fever and leukocytosis with 98.5% blastoid cells, was diagnosed as having AML (M1). Her leukemia cells were positive for CD13, CD33, and G-CSF receptor without chromosomal abnormality and responded to G-CSF in vitro. During chemotherapy, she died of progressive pneumonia. If our case is truly the first, the incidence of leukemia in donors may not be higher than that of naturally occurring leukemia. However, efforts towards an international long-term study, or at least to report every case similar to ours, would be required to be conclusive.


Subject(s)
Granulocyte Colony-Stimulating Factor/therapeutic use , Hematopoietic Stem Cell Mobilization/adverse effects , Leukemia, Myeloid, Acute/diagnosis , Tissue Donors , Female , Humans , Male , Middle Aged , Multiple Myeloma/therapy , Recombinant Proteins , Tissue and Organ Harvesting
16.
Biopharm Drug Dispos ; 22(6): 221-30, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11754038

ABSTRACT

The mechanism of the nonlinear pharmacokinetics of TAK-044 in rats was shown from in vivo and in vitro studies to be due to capacity-limited hepatic uptake. In the rats, which were given intravenous injections of (14)C-labeled TAK-044 ([(14)C]TAK-044) (1, 3, 10, 30 and 100 mg/kg), the AUC(inf) per unit dose of unchanged compound increased remarkably. An analysis model indicated that the CL(tot), V(1) and k(12) values of TAK-044 decreased significantly with increasing dose, whereas the k(el) values remained constant over the doses examined. The uptake clearance of [(14)C]TAK-044 by several tissues was investigated by an integration plot at doses from 0.3 to 60 mg/kg. This study showed that the liver played the principal role in the removal of TAK-044 from the plasma, while hepatic uptake was capacity-limited at doses greater than 30 mg/kg. The hepatic uptake study using rat hepatocytes indicated that a carrier-mediated transport system contributed to the hepatic uptake of TAK-044, and this system had high affinity (K(m,in vitro); 8.4 micromol/L) with low capacity (V(max,in vitro); 86.3 pmol/mg protein/min). These results show that the saturation of hepatic uptake by the carrier-mediated transport system could explain the nonlinear pharmacokinetics of TAK-044 in rats.


Subject(s)
Endothelins/antagonists & inhibitors , Peptides, Cyclic/pharmacokinetics , Animals , Antimetabolites/pharmacology , Area Under Curve , Bile/metabolism , Cell Separation , Dose-Response Relationship, Drug , Hepatocytes/drug effects , Hepatocytes/metabolism , In Vitro Techniques , Infusions, Intravenous , Liver/drug effects , Liver/metabolism , Male , Nonlinear Dynamics , Rats , Rats, Wistar
17.
Jpn J Antibiot ; 54(3): 103-11, 2001 Mar.
Article in Japanese | MEDLINE | ID: mdl-11392680

ABSTRACT

Diagnosis of fungal infections in compromised hosts has been difficult because of insufficient sensitivity and specificity of conventional methods such as culturing and serum testing. Therefore, antifungal agents are usually started in febrile patients who are resistant to antibiotics even if these monitoring tests were negative. In this study, therefore, in order to increase the reliability of these monitoring, polymerase chain reaction (PCR) methods for detection of blood fungus were also performed in compromised hosts including 14 patients with hematological malignancies and one with solid tumor who were undergoing chemotherapies. From these patients, total of 56 peripheral blood samples was collected periodically, irrespective of the presence of infectious signs. At each time point of venopuncture, status of the patient was allocated to one of the followings: A, receiving an intravenous antifungal therapy because of sustaining fever which had not responded to prior antibiotic therapies and also positive for culturing and/or serum beta-D-glucan tests; B, receiving an additional intravenous antifungal therapy but negative for culturing and serum-tests; C, febrile but not yet receiving any intravenous fungal therapy; D, afebrile status. During the study, 10 blood samples from 3 patients were allocated in group A, and one sample of them was positive while remaining 9 were all negative for PCR. Six samples from 4 patients were in group B, and one was PCR positive while remaining 5 were negative. Fifteen samples from 7 patients were in group C, and 3 were positive and 12 were negative for PCR. Twenty-five samples were in group D, and 5 were positive and 20 were negative for PCR. Thus, the results from fungal PCR in these patients were in some case showed discrepancies from those expected from the clinical course and/or conventional monitoring tests. Further evaluation of fungal PCR may gain insight into the more precise diagnosis of fungal infection in these patients.


Subject(s)
Immunocompromised Host , Mycoses/diagnosis , Opportunistic Infections/diagnosis , Polymerase Chain Reaction/methods , Adult , Female , Fungi/isolation & purification , Hematologic Neoplasms/complications , Humans , Male , Middle Aged , Mycoses/complications , Mycoses/microbiology , Opportunistic Infections/complications , Opportunistic Infections/microbiology
18.
Mol Cell ; 7(4): 811-22, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11336704

ABSTRACT

Endostatin, a collagen XVIII fragment, is a potent anti-angiogenic protein. We sought to identify its endothelial cell surface receptor(s). Alkaline phosphatase- tagged endostatin bound endothelial cells revealing two binding affinities. Expression cloning identified glypican, a cell surface proteoglycan as the lower-affinity receptor. Biochemical and genetic studies indicated that glypicans' heparan sulfate glycosaminoglycans were critical for endostatin binding. Furthermore, endostatin selected a specific octasulfated hexasaccharide from a sequence in heparin. We have also demonstrated a role for endostatin in renal tubular cell branching morphogenesis and show that glypicans serve as low-affinity receptors for endostatin in these cells, as in endothelial cells. Finally, antisense experiments suggest the critical importance of glypicans in mediating endostatin activities.


Subject(s)
Collagen/metabolism , Heparan Sulfate Proteoglycans/metabolism , Peptide Fragments/metabolism , 3T3 Cells , Animals , CHO Cells , Cloning, Molecular , Collagen Type XVIII , Cricetinae , Endostatins , Endothelium/cytology , Endothelium/metabolism , Gene Expression/physiology , Heparan Sulfate Proteoglycans/genetics , Heparin/metabolism , Heparin/pharmacology , Kidney Tubules/cytology , Kidney Tubules/metabolism , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Oligosaccharides/metabolism , Oligosaccharides/pharmacology , Protein Binding/physiology , Rats , Sulfates/metabolism , Sulfates/pharmacology
19.
J Comp Neurol ; 432(3): 285-95, 2001 Apr 09.
Article in English | MEDLINE | ID: mdl-11246208

ABSTRACT

Brevican is one of the most abundant extracellular matrix proteoglycans in the mammalian brain. We have previously shown that brevican produced by gray matter astrocytes constitutes a major component of perineuronal extracellular matrix in the adult brain. In this paper, we investigate the expression of brevican in the postnatal hippocampal fimbria to explore the role of the proteoglycan in central nervous system fiber tract development. We demonstrate that brevican is expressed by both oligodendrocytes and white matter astrocytes in the fimbria, but the expression of brevican in these two glial cell types is differently regulated during development. At P14, brevican immunoreactivity was observed throughout the fimbria, with particularly strong immunoreactivity in the developing interfascicular glial rows. In situ hybridization showed that oligodendrocytes in the glial rows strongly express brevican during the second and third postnatal weeks. Expression in oligodendrocytes was then down-regulated after P21. In the adult fimbria, no brevican expression was observed in oligodendrocytes. The time window of brevican expression coincides with the phase in which immature oligodendrocytes actively extend membrane processes and enwrap axon fibers. In contrast, the expression in astrocytes started around P21 as oligodendrocytes began to down-regulate the expression. In the adult fimbria, brevican expression was restricted to astrocytes. In situ hybridization with isoform-specific probes and RNase protection assays showed that the authentic, secreted form of brevican, not the glycosylphosphatidylinositol-anchored variant, is the predominant species expressed in the developing fimbria. Our results suggest that brevican plays a dual role in developing and adult fiber tracts.


Subject(s)
Aging/metabolism , Animals, Newborn/metabolism , Astrocytes/metabolism , Chondroitin Sulfate Proteoglycans/metabolism , Hippocampus/metabolism , Myelin Sheath/physiology , Nerve Tissue Proteins/metabolism , Oligodendroglia/physiology , Animals , Animals, Newborn/growth & development , Brevican , Central Nervous System/growth & development , Chondroitin Sulfate Proteoglycans/physiology , Female , Lectins, C-Type , Nerve Fibers/physiology , Nerve Tissue Proteins/physiology , Rats , Rats, Sprague-Dawley
20.
Dev Dyn ; 219(3): 353-67, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11066092

ABSTRACT

FGF2 is a crucial mitogen for neural precursor cells in the developing cerebral cortex. Heparan sulfate proteoglycans (HSPGs) are thought to play a role in cortical neurogenesis by regulating the action of FGF2 on neural precursor cells. In this article, we present data indicating that glypican-4 (K-glypican), a GPI-anchored cell surface HSPG, is involved in these processes. In the developing mouse brain, glypican-4 mRNA is expressed predominantly in the ventricular zone of the telencephalon. Neither the outer layers of the telencephalic wall nor the ventricular zone of other parts of the developing brain express significant levels of glypican-4, with the exception of the ventricular zone of the tectum. In cultures of E13 rat cortical precursor cells, glypican-4 is expressed in cells immunoreactive for nestin and the D1.1 antigen, markers of neural precursor cells. Glypican-4 expression was not detected in early postmitotic or fully differentiated neurons. Recombinant glypican-4 produced in immortalized neural precursor cells binds FGF2 through its heparan sulfate chains and suppressed the mitogenic effect of FGF2 on E13 cortical precursor cells. The spatiotemporal expression pattern of glypican-4 in the developing cerebral wall significantly overlaps with that of FGF2. These results suggest that glypican-4 plays a critical role in the regulation of FGF2 action during cortical neurogenesis.


Subject(s)
Brain/embryology , Brain/metabolism , Fibroblast Growth Factor 2/metabolism , Heparan Sulfate Proteoglycans/metabolism , Neurons/metabolism , Stem Cells/metabolism , Amino Acid Sequence , Animals , Base Sequence , Cells, Cultured , DNA Primers/genetics , Gene Expression Regulation, Developmental , Glypicans , Heparan Sulfate Proteoglycans/genetics , In Situ Hybridization , Mice , Nerve Regeneration/genetics , Nerve Regeneration/physiology , Protein Binding , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats
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