Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 150
Filter
1.
Nat Commun ; 10(1): 5614, 2019 12 09.
Article in English | MEDLINE | ID: mdl-31819056

ABSTRACT

Fast ignition (FI) is a promising approach for high-energy-gain inertial confinement fusion in the laboratory. To achieve ignition, the energy of a short-pulse laser is required to be delivered efficiently to the pre-compressed fuel core via a high-energy electron beam. Therefore, understanding the transport and energy deposition of this electron beam inside the pre-compressed core is the key for FI. Here we report on the direct observation of the electron beam transport and deposition in a compressed core through the stimulated Cu Kα emission in the super-penetration scheme. Simulations reproducing the experimental measurements indicate that, at the time of peak compression, about 1% of the short-pulse energy is coupled to a relatively low-density core with a radius of 70 µm. Analysis with the support of 2D particle-in-cell simulations uncovers the key factors improving this coupling efficiency. Our findings are of critical importance for optimizing FI experiments in a super-penetration scheme.

2.
Trop Biomed ; 36(2): 402-411, 2019 Jun 01.
Article in English | MEDLINE | ID: mdl-33597401

ABSTRACT

Schistosomiasis japonica is one of seven NTDs endemic in the Philippines that continues to threaten public health in the country. The causative agent, the blood fluke Schistosoma japonicum, uses an amphibious snail Oncomelania hupensis quadrasi which can harbor larval stages that multiply asexually, eventually producing the infective cercariae which are shed into the water. Contamination of freshwater bodies inhabited by the snail intermediate host occurs through release of human and animal feces containing S. japonicum eggs. Miracidia hatching from these eggs subsequently infect the snails that inhabit these water bodies. The degree of fecal contamination can vary across snail sites and influences snail infection rates in these sites. In this study, conventional malacological surveys using intensive manual search for snails were conducted from 2015 to 2016 in seven selected endemic provinces, namely Leyte and Bohol in the Visayas and Surigao del Norte, Agusan del Sur, Bukidnon, Lanao del Norte and Compostela Valley in Mindanao. A total of 6,279 O. hupensis quadrasi snails were collected from 38 snail sites. The municipality of Trento in Agusan del Sur recorded the highest number of snail sites (7) that yielded O. hupensis quadrasi snails while only one snail site was found positive for O. hupensis quadrasi snails in Kapatagan in Lanao del Norte and Talibon in Bohol. Alegria in Surigao del Norte yielded the highest number of snail sites (5) that were found to harbor snails positive for S. japonicum infection. The snail infection rates in this municipality ranged from 0.43% to 14.71%. None of the snails collected from Talibon in Bohol was infected. Bohol is the only province among the 28 schistosomiasis-endemic provinces which has reached near elimination status. Snail infection rates were found to vary considerably across snail sites, which could be due to the degree of fecal contamination of the snail sites and their connectivity to water that can serve as contamination source.

3.
Tropical Biomedicine ; : 402-411, 2019.
Article in English | WPRIM (Western Pacific) | ID: wpr-777847

ABSTRACT

@#Schistosomiasis japonica is one of seven NTDs endemic in the Philippines that continues to threaten public health in the country. The causative agent, the blood fluke Schistosoma japonicum, uses an amphibious snail Oncomelania hupensis quadrasi which can harbor larval stages that multiply asexually, eventually producing the infective cercariae which are shed into the water. Contamination of freshwater bodies inhabited by the snail intermediate host occurs through release of human and animal feces containing S. japonicum eggs. Miracidia hatching from these eggs subsequently infect the snails that inhabit these water bodies. The degree of fecal contamination can vary across snail sites and influences snail infection rates in these sites. In this study, conventional malacological surveys using intensive manual search for snails were conducted from 2015 to 2016 in seven selected endemic provinces, namely Leyte and Bohol in the Visayas and Surigao del Norte, Agusan del Sur, Bukidnon, Lanao del Norte and Compostela Valley in Mindanao. A total of 6,279 O. hupensis quadrasi snails were collected from 38 snail sites. The municipality of Trento in Agusan del Sur recorded the highest number of snail sites (7) that yielded O. hupensis quadrasi snails while only one snail site was found positive for O. hupensis quadrasi snails in Kapatagan in Lanao del Norte and Talibon in Bohol. Alegria in Surigao del Norte yielded the highest number of snail sites (5) that were found to harbor snails positive for S. japonicum infection. The snail infection rates in this municipality ranged from 0.43% to 14.71%. None of the snails collected from Talibon in Bohol was infected. Bohol is the only province among the 28 schistosomiasis-endemic provinces which has reached near elimination status. Snail infection rates were found to vary considerably across snail sites, which could be due to the degree of fecal contamination of the snail sites and their connectivity to water that can serve as contamination source.

4.
Parasitology ; 136(10): 1147-60, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19631010

ABSTRACT

Three cDNAs encoding rhoptry-associated protein 1 (RAP-1) homologues were found in the Babesia gibsoni EST database. Based on similarities to BgRAP-1a, which was identified previously by serological screening of a cDNA merozoite library, the two new genes were designated BgRAP-1b (33.7%) and BgRAP-1c (57%). Mice antiserum raised against each recombinant protein reacted specifically with B. gibsoni parasites as determined by Western blotting, which showed native molecular sizes of the BgRAP-1a (51 kDa), BgRAP-1b (53 kDa) and BgRAP-1c (47 kDa) consistent with predictable molecular weights. Immunofluoresence using these antibodies revealed localization of all BgRAP-1s within the matrix of merozoites; however, BgRAP-1a appeared to diverge from the other two when it was found secreted into the cytoplasm of infected erythrocytes. Apical localization of all 3 BgRAP-1s during the extracellular stage of the parasite combined with their ability to bind a canine erythrocyte membrane fraction was suggestive of a role for these proteins in erythrocyte attachment. Lastly, the ability of these recombinant proteins to be used as diagnostic reagents was tested by ELISA and the sensitivities of BgRAP-1a and BgRAP-1c were found increased through N-terminal truncation. Taken together, our data suggest divergent roles for the 3 BgRAP-1s in the merozoite stage of B. gibsoni.


Subject(s)
Babesiosis/veterinary , Dog Diseases/diagnosis , Protozoan Proteins , Animals , Babesia/classification , Babesia/genetics , Babesia/immunology , Babesia/metabolism , Babesiosis/diagnosis , Babesiosis/parasitology , Blotting, Western , DNA, Protozoan/analysis , Dog Diseases/parasitology , Dogs , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique , Mice , Microscopy, Confocal , Molecular Sequence Data , Protozoan Proteins/genetics , Protozoan Proteins/immunology , Protozoan Proteins/metabolism , Sequence Analysis, DNA
5.
Parasite Immunol ; 31(6): 328-40, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19493212

ABSTRACT

Serological immunoscreening was used to identify a gene encoding heat shock protein-70 from Babesia gibsoni (BgHSP-70) that showed high homology with HSP-70s from other apicomplexan parasites. This gene corresponded to a full-length cDNA containing an open reading frame of 1968 bp predicted to result in a 70-kDa mature protein consisting of 656 amino acids. Analysis of the expression levels of BgHSP-70 indicated elevated transcription from cultured parasites incubated at 40 degrees C for 1 h, but not at 30 degrees C. Interestingly, antiserum raised against recombinant BgHSP-70 protein reacted specifically not only with a 70-kDa protein of B. gibsoni but also with a corresponding native protein of B. microti (BmHSP-70), indicating the high degree of conservation of this protein. The BmHSP-70 gene was then isolated and characterized and the immunoprotective properties of recombinant BgHSP-70 (rBgHSP-70) and rBmHSP-70 were compared in vitro and in vivo. Both proteins had potent mitogenic effects on murine and canine mononuclear cells as evidenced by high proliferative responses and IFN-gamma production after stimulation. Immunization regimes in BALB/c and C57BL/6 mice using rBgHSP-70 and rBmHSP-70 elicited high antibody levels, with concurrent significant reductions in peripheral parasitaemias. Taken together, these results emphasize the potential of HSP-70s as a molecular adjuvant vaccine.


Subject(s)
Babesia/genetics , Babesia/immunology , HSP70 Heat-Shock Proteins/genetics , HSP70 Heat-Shock Proteins/immunology , Protozoan Proteins/genetics , Protozoan Proteins/immunology , Animals , Antibodies, Protozoan , Babesia microti/genetics , Babesia microti/immunology , Cell Proliferation , Cells, Cultured , DNA, Protozoan/genetics , Dogs , Gene Expression Profiling , HSP70 Heat-Shock Proteins/chemistry , Hot Temperature , Interferon-gamma/metabolism , Leukocytes, Mononuclear/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Molecular Weight , Open Reading Frames , Parasitemia/prevention & control , Protozoan Proteins/chemistry , Protozoan Vaccines/immunology , Vaccines, Synthetic/immunology
6.
Parasite Immunol ; 30(6-7): 365-70, 2008.
Article in English | MEDLINE | ID: mdl-18533933

ABSTRACT

We have studied the impact of complement component 3 (C3) deficiency on the progression of lethal Babesia rodhaini infection in immune mice. A B. gibsoni ribosomal phosphoprotein P0 (BgP0) previously reported to be a cross-protective antigen against Babesia infection was used to immunize C57BL/6 wild-type (WT) and C3-deficient (C3-/-) mice. Test mice were immunized intraperitoneally (i.p.) with recombinant BgP0 (rBgP0), while controls either were immunized with PBS or did not receive any immunization. Following the immunization regime, test WT mice induced a specifically strong humoral response consisting of mixed immunoglobulins IgG1 and IgG2 associated with high production of IFN-gamma in the supernatant of splenocytes. While test C3-/- mice had significantly decreased total IgG, IgG1 and IgG2b responses, the secretions of IL-12 and IFN-gamma tended to be lower than those in WT mice. Furthermore, partial protection was only observed in rBgP0-immunized WT mice but not in C3-/- mice or controls. Indeed, rBgP0-immunized WT mice showed significant reductions in the initiation of parasitaemia correlated with delayed mortalities and considerable survival rates. Taken together, our results indicate that cross-protection was impaired in C3-/- mice in view of the decrease in the antibody responses and cytokine production and the high susceptibility to infection.


Subject(s)
Antigens, Protozoan/immunology , Babesia , Babesiosis/immunology , Babesiosis/prevention & control , Complement C3/immunology , Immunization , Protozoan Vaccines/immunology , Ribosomal Proteins/immunology , Animals , Antibodies, Protozoan/blood , Antigens, Protozoan/genetics , Babesia/immunology , Babesiosis/blood , Cells, Cultured , Complement C3/deficiency , Complement C3/genetics , Female , Immunoglobulin G/blood , Injections, Intraperitoneal , Interferon-gamma/biosynthesis , Interleukin-12/biosynthesis , Mice , Mice, Inbred C57BL , Mice, Knockout , Protozoan Vaccines/administration & dosage , Ribosomal Proteins/genetics , Spleen/immunology , Spleen/metabolism , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/immunology
7.
Horm Metab Res ; 39(3): 212-7, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17373637

ABSTRACT

The roles of free fatty acids (FFA), tumor necrosis factor-alpha (TNF-alpha), and adiponectin in the development of the insulin-resistant metabolic disorder in several subjects have been studied. A total of 70 Japanese male subjects were selected according to the following three sets of criteria: subjects in group A had, (1) a fasting plasma glucose (FPG)>or=110 to <140 mg/dl, (2) a triglyceride (TG) level>or=150 mg/dl, (3) a systolic blood pressure (SBP)>or=140 and/or diastolic blood pressure (DBP)>or=90 mmHg, and (4) a body mass index (BMI)>or=25 kg/m2 (age=53.4+/-8.5 years, BMI=27.0+/-1.3 kg/m2, n=16). Subjects in group B had, (1) FPG<110 mg/dl, (2) TG<150 mg/dl, (3) SBP<140 and DBP<90 mmHg, and (4) BMI>or=25 kg/m2 (age=47.2+/-10.3 years, BMI=26.6+/-1.31 kg/m2, n=38). Subjects in group C had, (1) FPG<110 mg/dl, (2) TG<150 mg/dl, (3) SBP<140 and DBP<90 mmHg, and (4) 20>or=BMI<22 kg/m2 (age=50.4+/-9.3 years, BMI=20.9+/-0.6 kg/m2, n=16). The homeostasis model assessment of insulin resistance in group A (2.7+/-1.4) was significantly higher (p<0.0001) than in groups B (1.6+/-0.7) and C (0.9+/-0.5). FFA in group A (1.17+/-0.57 mEq/l) was significantly higher than in groups B (0.62+/-0.23 mEq/l) and C (0.48+/-0.16 mEq/l) (p<0.0001). Serum TNF-alpha in group A (1.36+/-0.62 pg/ml) was significantly higher than in groups B (0.95+/-0.35 pg/ml; p=0.003) and C (0.76+/-0.09 pg/ml; p=0.0013). No significant differences in the serum level of adiponectin were observed between groups A and B or between groups B and C. The results suggest that FFA and possibly TNF-alpha levels are closely related to the development of insulin resistance in subjects with metabolic disorders.


Subject(s)
Fatty Acids, Nonesterified/blood , Insulin Resistance/physiology , Metabolic Syndrome/metabolism , Tumor Necrosis Factor-alpha/blood , Adiponectin/blood , Body Mass Index , Humans , Male , Middle Aged
8.
Ann Trop Med Parasitol ; 97(3): 237-43, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12803855

ABSTRACT

The vitamin-A uptake of Plasmodium falciparum was investigated by culturing a standard isolate of the parasite (FCR-3) with (3)H-labelled vitamin A, at concentrations of the vitamin corresponding to those normally present in human serum. The (3)H-labelled vitamin A accumulated in the parasites from each culture in a parasitaemia-dependent manner. The radioactivity detected in the parasites increased with parasite maturation from the ring to the late-trophozoite stage. In addition, most of the radioactivity incorporated into the parasite cells was in the cytoplasm. The accumulation of vitamin A in the cytoplasm of late trophozoites indicates that P. falciparum may use vitamin A, from its human host, as an antioxidant, to protect itself from oxidative stress while intra-erythrocytic. The amount of the vitamin taken up by the parasite in vitro is small compared with the deficit that sometimes causes severe hypovitaminosis A in malaria cases. Consumption of vitamin A by the parasites together with the systemic decreases in non-enzymatic antioxidants that are seen in malaria may together cause this characteristic hypovitaminosis.


Subject(s)
Plasmodium falciparum/metabolism , Vitamin A/pharmacokinetics , Animals , Culture Media , Erythrocytes/parasitology , Humans , Parasitemia/parasitology , Plasmodium falciparum/growth & development , Time Factors , Vitamin A Deficiency/parasitology
9.
Horm Metab Res ; 34(10): 577-82, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12439786

ABSTRACT

Diabetes is frequently associated with hyperlipidemia, which results in atherogenic complications. Insulin-dependent diabetes mellitus (IDDM) model BB/Wor//Tky (BB) rats exhibit both hyperglycemia and hyperlipidemia and die within 3 weeks after the onset of diabetes unless insulin therapy is given. We performed insulin gene therapy in BB rats with adenovirus vectors through the tail vein. After infusion, plasma triglyceride levels dropped quickly and maintained low levels for 1 week, whereas blood glucose levels showed a slight decrease. The survival period of diabetic BB rats was prolonged to up to 75 days by infusing insulin gene-expressing adenoviral vectors. We suggest that the control of hyperlipidemia can be a life-saving measure when combined with hyperglycemia control in the treatment of diabetes.


Subject(s)
Diabetes Mellitus, Type 1/therapy , Genetic Therapy/methods , Hyperlipidemias/therapy , Insulin/genetics , Adenoviridae/genetics , Animals , Blood Glucose/metabolism , Cholesterol/blood , Diabetes Mellitus, Type 1/blood , Fatty Acids, Nonesterified/blood , Female , Genetic Vectors , Hyperlipidemias/blood , Insulin/biosynthesis , Insulin/blood , Lipoproteins/blood , Male , Rats , Rats, Inbred BB , Triglycerides/blood
10.
J Int Med Res ; 29(4): 280-6, 2001.
Article in English | MEDLINE | ID: mdl-11675900

ABSTRACT

This 7-year retrospective longitudinal study was carried out in order to clarify the clinical features of elderly type 2 diabetic patients with microalbuminuria. Elderly Japanese type 2 diabetic patients (n = 22; age 50 - 73 years) with microalbuminuria were studied retrospectively. Patients whose urinary albumin excretion rate (UAER) decreased 7 years were considered 'nonprogressors' (n = 8) whereas those whose UAER increased were considered 'progressors' (n = 14). The mean 7-year level of glycosylated haemoglobin (HbA1c) did not differ significantly between non-progressors and progressors but the mean 7-year blood pressure (BP) of progressors (101 +/- 8 mmHg) was significantly higher than that of non-progressors (92 +/- 7 mmHg). In progressors who received no anti-hypertensive drugs, systolic BP was above the BP goal of 130/85 mmHg but mean BP and diastolic BP were below this goal. The results are consistent with the view that hypertension affects the progression of microalbuminuria; raised systolic BP may be a factor in this progression in elderly type 2 diabetic patients.


Subject(s)
Albuminuria/etiology , Albuminuria/physiopathology , Blood Pressure/physiology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/physiopathology , Aged , Antihypertensive Agents/therapeutic use , Apolipoproteins E/blood , Apolipoproteins E/genetics , Diabetic Nephropathies/etiology , Diabetic Nephropathies/physiopathology , Diabetic Nephropathies/prevention & control , Female , Follow-Up Studies , Humans , Hypertension/complications , Hypertension/drug therapy , Hypertension/physiopathology , Japan , Longitudinal Studies , Male , Middle Aged , Phenotype , Retrospective Studies , Risk Factors
11.
Mol Biochem Parasitol ; 116(1): 73-9, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11463468

ABSTRACT

We have identified the 2-Cys peroxiredoxin (PfPrx-1) from the human malaria parasite Plasmodium falciparum. The PfPrx-1 showed the highest identity at amino acid level to the type II Prx among the currently known six subfamilies of mammalian Prx. The sequence identity between the PfPrx-1 and the previously reported 1-Cys Prx of P. falciparum (PfPrx-2), which corresponded to mammalian type VI Prx, was 25%. This suggests that the parasite possesses two Prx subfamilies. The PfPrx-1 showed significant sequence similarities with those of 2-Cys peroxiredoxins of plants in the BLASTX search. This may reflect the consequences of a genetic transfer from an algal endosymbiont to the parasite nucleus during evolution. The recombinant PfPrx-1 protein (rPfPrx-1) was expressed as a histidine fusion protein in Escherichia coli and purified with Ni chromatography. The rPfPrx-1 existed as dimers under non-reducing conditions and dissociated into monomers in the presence of dithiothreitol. The PfPrx-1 protein also exists as a dimer in the parasites themselves. The reduction of the oxidized enzyme by the donation of electrons from E. coli thioredoxin (Trx)/Trx reductase system was demonstrated in its reaction with H(2)O(2), using the rPfPrx-1 protein. These results suggested that the PfPrx-1 can act as a terminal peroxidase of the parasite Trx system. An elevated expression of the PfPrx-1 protein seen in the trophozoite, the stage with active metabolism, suggests an association of the parasite Trx system with its intracellular redox control.


Subject(s)
Peroxidases/genetics , Plasmodium falciparum/genetics , Amino Acid Sequence , Animals , Antioxidants , Cloning, Molecular , Molecular Sequence Data , Peroxiredoxin VI , Peroxiredoxins , Plasmodium falciparum/enzymology , Plasmodium falciparum/pathogenicity , Protozoan Proteins/genetics , Sequence Analysis, DNA , Sequence Homology, Amino Acid
12.
Metabolism ; 49(9): 1118-23, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11016890

ABSTRACT

We have recently identified a novel gene, klotho (kl), which may suppress several aging phenotypes. A defect of kl gene expression in the mouse results in a syndrome resembling human aging, such as arteriosclerosis, skin atrophy, osteoporosis, and pulmonary emphysema. To determine whether mouse homozygotes for the kl mutation (kl/kl) show abnormal glucose metabolism, an oral glucose tolerance test (OGTT) was performed at 6 to 8 weeks of age. Blood glucose levels during the OGTT were significantly lower in kl/kl mice versus wild-type mice. The insulin content of the pancreas was significantly lower in kl/kl mice compared with wild-type mice. Decreased insulin production was also supported by Northern blot analysis showing lower levels of insulin mRNA in kl/kl mice. To examine how lower blood glucose levels may exist in kl/kl mice despite decreased insulin production, insulin tolerance tests (ITTs) were performed. The glucose decline following insulin injection was more severe in kl/kl mice versus wild-type mice, suggesting that insulin sensitivity was higher in kl/kl mice versus wild-type mice. In kl/kl mice, an augmented expression of GLUT4 in skeletal muscle was demonstrated by both Northern blot analysis and Western blot analysis. Thus, we conclude that insulin production is decreased and insulin sensitivity is increased in the klotho mouse, a novel animal model for human aging.


Subject(s)
Aging/physiology , Insulin/blood , Insulin/pharmacology , Models, Biological , Muscle Proteins , Adrenocorticotropic Hormone/blood , Animals , Blood Glucose/analysis , Gene Expression , Glucose Tolerance Test , Glucose Transporter Type 4 , Growth Hormone/blood , Humans , Hypoglycemia/metabolism , Islets of Langerhans/anatomy & histology , Islets of Langerhans/metabolism , Mice , Mice, Mutant Strains , Monosaccharide Transport Proteins/genetics , Monosaccharide Transport Proteins/metabolism , Muscle, Skeletal/metabolism , RNA, Messenger/analysis , Thyrotropin/blood
14.
Eur J Pharmacol ; 398(3): 409-14, 2000 Jun 23.
Article in English | MEDLINE | ID: mdl-10862831

ABSTRACT

We investigated the therapeutic effect of branched chain amino acids (BCAA) on mice with glucose intolerance induced by encephalomyocarditis virus (EMCV). Male DBA/2 mice were divided into three groups: treated with BCAA, (such as valine, leucine, and isoleucine), untreated, and control. BCAA-treated and -untreated groups were inoculated intraperitoneally with the NDK25 variant of EMCV at 200 plaque-forming units per mouse. The BCAA-treated group was administered orally 0.9 g/kg/day of each BCAA from the day after viral inoculation. The control group neither received virus inoculation nor was treated with BCAA. One week after inoculation, oral glucose tolerance tests (OGTT) were performed. After the glucose loading at 1.5 g/kg of body weight, blood glucose levels in the untreated group were 92.0+/-10.0 mg/dl at baseline, 224.6+/-10.9 mg/dl at 30 min, and 169.4+/-21.4 mg/dl at 60 min, which were significantly (P<0.05) higher than those in the control group (62. 7+/-3.6 mg/dl, 167.2+/-16.4, and 83.8+/-6.0 mg/dl, respectively). Blood glucose levels in the BCAA-treated group were 54.5+/-3.7 mg/dl at baseline, 145.2+/-8.7 mg/dl at 30 min, and 128.7+/-18.3 mg/dl at 60 min after the glucose loading, which were not significantly higher than those in the control group. Immunoreactive insulin levels at 30 min after the glucose loading were lower in the untreated group than in the control group at 1 week after virus inoculation. Histological investigations showed that the grade of insulitis in the pancreas of mice of the BCAA-treated group was lower than that of the mice of the untreated group. These results suggest that oral administration of BCAA is able to improve glucose intolerance induced by EMCV.


Subject(s)
Amino Acids, Branched-Chain/therapeutic use , Glucose Intolerance/drug therapy , Administration, Oral , Amino Acids, Branched-Chain/pharmacology , Animals , Blood Glucose/drug effects , Cardiovirus Infections , Encephalomyocarditis virus , Glucose Intolerance/virology , Male , Mice , Mice, Inbred DBA , Pancreas/drug effects , Pancreas/pathology
15.
Arterioscler Thromb Vasc Biol ; 20(4): 1155-61, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10764687

ABSTRACT

A decline in oxygen concentration perturbs endothelial function, which promotes local thrombosis. In this study, we determined whether hypoxia in the range of that observed in pathophysiological hypoxic states stimulates plasminogen activator inhibitor-1 (PAI-1) production in bovine aortic endothelial cells. PAI-1 production, measured by ELISA, was increased by 4.7-fold (P<0.05 versus normoxic control, n=4) at 12 hours after hypoxic stimulation. Northern blot analysis showed the progressive time-dependent increase in the steady-state level of PAI-1 mRNA expression by hypoxia, which reached a 7.5-fold increase (P<0.05 versus control, n=4) at 12 hours. Deferoxamine, which has been known to bind heme protein and to reproduce the hypoxic response, induced PAI-1 production at both the mRNA and protein levels. The half-life of PAI-1 mRNA, as determined by a standard decay assay, was not affected by hypoxia, suggesting that induction of PAI-1 mRNA was regulated mainly at the transcriptional level. Transient transfection assays of the human PAI-1 promoter-luciferase construct indicates that a hypoxia-responsive region lies between -414 and -107 relative to the transcription start site, where no putative hypoxia response element is found. The hypoxia-mediated increase in PAI-1 mRNA levels was attenuated by the tyrosine kinase inhibitors genistein (50 micromol/L) and herbimycin A (1 micromol/L), whereas PD98059 (50 micromol/L, MEK1 inhibitor), SB203580 (10 micromol/L, p38 mitogen-activated protein kinase inhibitor), and calphostin C (1 micromol/L, protein kinase C inhibitor) had no effect on the induction of PAI-1 expression by hypoxia and deferoxamine. Genistein but not daidzein blocked the production of hypoxia- and deferoxamine-induced PAI-1 protein. Thus, we conclude that hypoxia stimulates PAI-1 gene transcription and protein production through a signaling pathway involving genistein-sensitive tyrosine kinases in vascular endothelial cells.


Subject(s)
Cell Hypoxia , Endothelium, Vascular/metabolism , Genistein/pharmacology , Plasminogen Activator Inhibitor 1/genetics , Protein-Tyrosine Kinases/metabolism , Transcription, Genetic , Animals , Aorta , Benzoquinones , Blotting, Northern , Cattle , Cells, Cultured , Deferoxamine/pharmacology , Enzyme Inhibitors/pharmacology , Enzyme-Linked Immunosorbent Assay , Gene Expression/drug effects , Lactams, Macrocyclic , Promoter Regions, Genetic , Protein-Tyrosine Kinases/antagonists & inhibitors , Quinones/pharmacology , RNA, Messenger/metabolism , Recombinant Fusion Proteins , Rifabutin/analogs & derivatives , Transcription, Genetic/drug effects , Transfection
16.
Article in English | MEDLINE | ID: mdl-12567693

ABSTRACT

OBJECTIVE: To evaluate the diagnostic value of the recombinant antigen of 39 amino acid repeats encoded by a kinesin-like gene of Leishmania changasi (rK39) in serodiagnosis of visceral leishmaniasis (VL). METHODS: In Kashi, Xinjiang, 13 VL patients with splenomegaly and bone marrow aspirate culture positive were subjected to dipstick assay. A drop of whole blood or serum from patient was placed at the absorbing pad at the bottom of the dipstick. Flooding of the bottom protein with buffer allows serum proteins to migrate upwards, producing the positive band and Western blot analysis of rK39 subsequently performed with the sera collected. RESULTS: The end-point titers of anti-rK39 antibodies of these sera were determined by ELISA and found to fall within the range of 10(-2) to 10(-4), which were consistent with the intensity of their reaction with rK39 in dipstick assay. The positive sera could also recognize the specific rK39 band as analyzed by Western blot analysis. CONCLUSION: The rK39 dipstick assay is more rapid, specific, sensitive and less invasive than the conventional methods of diagnosis for VL in the areas of low endemicity.


Subject(s)
Antigens, Protozoan/immunology , Leishmania donovani/immunology , Leishmaniasis, Visceral/diagnosis , Reagent Strips , Animals , Antibodies, Protozoan/blood , Humans , Leishmaniasis, Visceral/immunology , Recombinant Proteins/immunology
17.
Nihon Rinsho ; 57 Suppl: 508-13, 1999 Aug.
Article in Japanese | MEDLINE | ID: mdl-10503486

Subject(s)
Dipeptidases/blood , Humans
18.
Int J Parasitol ; 29(4): 613-8, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10428638

ABSTRACT

In order to examine the taxonomic relationship of Theileria sp. of Asian buffalo to the benign Theileria spp. of cattle, we sequenced and compared the major piroplasm protein (p33/34) genes of these parasites. The two consensus sequences determined for the buffalo parasite were of the same length (852 bp) and showed >80% identity with the sequences of the homologous genes (849 bp) in the cattle parasites. Alignment of the inferred aa sequences with those of Theileria sergenti and Theileria buffeli predicted that there is an insertion of a single residue at the N-terminus in the inferred polypeptide of the buffalo parasite. Phylogenetic analyses based on the aa sequences suggested that Theileria sp. of the Asian buffalo should be classified within the benign Theileria parasite group as a separate species from the cattle parasites. Based on this, we propose a rearrangement of the currently used classification for the benign Theileria species in cattle and Asian buffalo.


Subject(s)
Antigens, Protozoan/genetics , Genes, Helminth , Protozoan Proteins/genetics , Theileria/genetics , Amino Acid Sequence , Animals , Buffaloes/parasitology , Cattle , Molecular Sequence Data , Phylogeny , Sequence Alignment , Species Specificity , Theileria/chemistry , Theileria/classification
19.
Vet Parasitol ; 83(2): 99-105, 1999 Jun 15.
Article in English | MEDLINE | ID: mdl-10392966

ABSTRACT

Classification of Theileria parasites of south-east Asian countries is still ambiguous due to the lack of basic studies, especially their molecular genetic information. In this study, we included 6 known species and 14 unclassified Theileria parasite isolates: Theileria annulata, Theileria parva, Theileria taurotragi, Theileria sergenti, Theileria buffeli, Theileria types Sable, Theileria types A, B, B1, B2, C, D, E, F, G, G1, Theileria type Medan (Indonesia), Theileria type Ipoh (Malaysia) and Theileria type Thong Song (Thailand). Small subunit ribosomal RNA (srRNA) nucleotide sequence data were collected by PCR, cloning and dideoxy sequencing. The srRNA nucleotide sequences were aligned and analyzed by distance methods, maximum parsimony algorithms and maximum likelihood methods to construct phylogenetic trees. Bootstrap analysis was used to test the strength of the different phylogenetic reconstructions. The data indicated that all of the tree-building methods gave very similar results. This study identified two groups of Theileria, the pathogenic and benign groups, which are strongly supported by bootstrap analysis. The analysis also indicated that three subgroups (A, B and C) were generated within the benign Theileria group whereas the classification of Theileria type D and Thong Song is questionable. However, more basic information such as life cycle differences, vectors, modes of transmission, virulent and genetic/sexual compatability is essential for clearer taxonomic definition of the benign Theileria parasites.


Subject(s)
Phylogeny , RNA, Ribosomal/genetics , Theileria/genetics , Animals , Asia, Southeastern , Base Sequence , DNA, Protozoan/chemistry , Molecular Sequence Data , Polymerase Chain Reaction , RNA, Ribosomal/chemistry , Sequence Alignment , Sequence Analysis, DNA , Sequence Homology, Nucleic Acid , Theileria/classification , Theileriasis/parasitology
20.
Ann Clin Biochem ; 36 ( Pt 2): 221-5, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10370741

ABSTRACT

Renal dipeptidase (EC 3.4.13.19) activity in serum and urine from healthy volunteers (n = 20), patients with diabetes (n = 18) and patients with chronic renal failure (n = 5) was measured using glycyl-D-alanine as substrate. The assay was highly specific for the enzyme and was not affected by the various aminopeptidases present in serum and urine. No difference in serum renal dipeptidase activity was observed between the groups. The enzyme activity (U/L) in urine was higher than that in serum, irrespective of the group, suggesting the urine concentration was not affected by the serum concentration. The mean renal dipeptidase activities in urine were 2.56, 2.46 and 0.78 U/mol creatinine for healthy subjects, patients with diabetes and patients with chronic renal failure, respectively. The renal dipeptidase activity was significantly lower in the chronic renal failure group. The urinary excretion of dipeptidase (U/mmol creatinine) showed significant inverse correlations with that of beta 2-microglobulin, albumin and alpha 1-microglobulin, and with serum concentrations of creatinine, beta 2-microglobulin and alpha 1-microglobulin. We suggest that urine dipeptidase may be a useful marker of renal diseases.


Subject(s)
Dipeptidases/urine , Kidney Failure, Chronic/enzymology , Adult , Aged , Amino Acids/blood , Amino Acids/metabolism , Animals , Diabetes Mellitus/diagnosis , Diabetes Mellitus/enzymology , Dipeptidases/blood , Female , Humans , Kidney Failure, Chronic/diagnosis , Male , Middle Aged , Swine
SELECTION OF CITATIONS
SEARCH DETAIL
...