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Biomedical subjects

S Kano

Publications and source records attributed to S Kano.

At least 19 recordsLinked to original sources

In vivo assessment of the cutaneous bioavailability of topically applied maxacalcitol.

Maxacalcitol (22-oxacalcitriol), a vitamin D3 analogue, is widely used for the treatment of psoriasis. The effects of topical dermatologic drugs have been assessed by their pharmacodynamic activities, and concentrations in the skin correlate with these activities. In this study, we assessed the cutaneous bioavailability of topically applied maxacalcitol ointment in vivo by tape stripping. Six drug application sites were randomly assigned on the left volar forearm of six healthy men. Fifty milligrams of maxacalcitol ointment (25 microg/g) was applied to each site. After 0 (15 s), 0.5, 1, 2, 4, or 6 h, the ointment was gently removed, and tape stripping was performed. Maxacalcitol was extracted from the tape strips and quantified by liquid chromatographic tandem mass spectrometry. Average concentrations of maxacalcitol in the stratum corneum (SC) were 2.61, 4.37, 6.23, 9.37, and 9.46 microg/g at 0.5, 1, 2, 4, and 6 h, respectively, after drug application. The steady state was attained approx. 4 h after drug application. The cutaneous bioavailability of topical maxacalcitol ointment can be assessed by the tape-stripping method. This approach will probably be useful in the assessment of the bioequivalence of topical dermatologic products and as a parameter for pharmacokinetic/pharmacodynamic studies.

Adhesives↗

An open randomized clinical trial of Artekin vs artesunate-mefloquine in the treatment of acute uncomplicated falciparum malaria.

Malaria remains a major cause of morbidity and mortality in tropical countries and subtropical regions in the world. Southeast Asia has the most resistant malaria parasites in the world, which has limited treatment options in this region. In response to this situation, short-course artemisinin-based combination therapies (ACTs) have been developed. The combination of dihydroartemisinin (DHA) and piperaquine (PQP) in the form of Artekin has been developed as an alternative to established combinations, such as artesunate-mefloquine, primarily to reduce treatment costs and toxicity. We conducted a study comparing a standard treatment for acute uncomplicated falciparum malaria (artesunate 4 mg/kg/day together with mefloquine 8 mg/kg/day oral route once a day for 3 days) (Group A) and a combination of dihydroartemisinin 40 mg and piperaquine 320 mg in the form of Artekin given once a day for 3 days (Group B) to determine safety, efficacy, and tolerability. One hundred and eighty patients were randomly enrolled at the ratio of 1:2 into groups A:B. All patients had rapid initial clinical and parasitological responses. There were no significant differences in fever clearance time or parasite clearance time between both groups. The 28-day cure rates were high, at 100% and 99%, in groups A and B, respectively. We conclude that Artekin was as effective and well-tolerated as artesunate-mefloquine, and can be used alternatively as the current treatment for multidrug-resistant P. falciparum malaria.

Acute Disease↗

The pharmacokinetics of oral dihydroartemisinin and artesunate in healthy Thai volunteers.

The pharmacokinetics of oral dihydroartemisinin (DHA) following the dose of 2 and 4 mg/ kg body weight dihydroartemisinin (Twisinin, T-2 Program, Thailand) and 4 mg/kg body weight oral artesunate (AS; Guilin Pharmaceutical Works, Guangxi, China) were investigated in 20 healthy Thai volunteers (10 males, 10 females). All formulations were generally well tolerated. Oral DHA was rapidly absorbed from gastrointestinal tract with marked inter-individual variation. The pharmacokinetics of DHA following the two dose levels were similar and linearity in its kinetics was observed. Based on the model-independent pharmacokinetic analysis, median (95% CI) values for Cmax of 181 (120-306) and 360 (181-658) ng/ml were achieved at 1.5 hours following 2 and 4 mg/kg body weight dose, respectively. The corresponding values for AUC0-infinity, t1/2z, CL/f and Vz/f were 377 (199-1,128) vs 907 (324-2,289) ng.h/ml, 0.96 (0.70-1.81) vs 1.2 (0.75-1.44) hours, 7.7 (4.3-12.3) vs 6.6 (3.1-10.1) l/kg, and 90.5 (28.6-178.2) vs 6.6 (3.1-10.1) ml/min/kg, respectively (2 vs 4 mg/kg dose). Oral AS was rapidly biotransformed to DHA, which was detectable in plasma as early as 15 minutes of AS dosing. Following 4 mg/kg dose, median (95% CI) value for Cmax of 519 (236-284) ng/ml was achieved at 0.7 (0.25-1.5) hours. AUC0-infinity, and t1/2z were 657 (362-2,079) ng.h/ml, 0.74 (0.34-1.42) hours, respectively. Cmax of DHA following oral AS were significantly higher, but total systemic exposure was greater following oral DHA at the same dose level (4 mg/kg body weight). There was no significant sex difference in pharmacokinetics of DHA.

Administration, Oral↗

High proliferative potential colony-forming cells (HPP-CFCs) in the peripheral blood of rheumatoid arthritis patients with interstitial lung disease.

OBJECTIVE: To examine the presence of high proliferative potential colony-forming cells (HPP-CFCs) in the peripheral blood of rheumatoid arthritis (RA) patients with and without interstitial lung disease (ILD). METHODS: Peripheral blood mononuclear cells from 35 RA patients with and without ILD, 12 patients with infectious pulmonary diseases, 10 patients with idiopathic pulmonary fibrosis (IPF), and 20 healthy volunteers, were assayed for in vitro colony formation. RESULTS: HPP-CFCs were detected significantly more frequently in the peripheral blood of patients with ILD (11/14: 78%, p<0.05) than in that of patients without ILD (4/21: 19%). HPP-CFCs were not detected in the peripheral blood of patients with infectious pulmonary diseases, those with IPF or healthy volunteers. CONCLUSIONS: HPP-CFCs were frequently found in the peripheral blood of RA patients with ILD compared with those without ILD, suggesting the mobilization of HPP-CFCs from the bone marrow into the peripheral blood in association with ILD in RA.

Arthritis, Rheumatoid↗

In-vitro uptake of vitamin A by Plasmodium falciparum.

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.

Animals↗

Comparative clinical trial of two-fixed combinations dihydroartemisinin-napthoquine-trimethoprim (DNP) and artemether-lumefantrine (Coartem/Riamet) in the treatment of acute uncomplicated falciparum malaria in Thailand.

An open randomized comparison of two-fixed dose artemisinin derivative-containing combination regimens was conducted in adults with acute uncomplicated multidrug resistant falciparum malaria in Thailand. DNP, a combination of dihydroartemisinin with napthoquine and trimethoprim developed recently in China, has been evaluated in China, Vietnam, Cambodia and Thailand. This study was performed to compare the safety, tolerability and efficacy of DNP and artemether-lumefantrine/Coartem. One hundred and thirty eligible uncomplicated falciparum malaria patients were enrolled into the study. Patients were randomly assigned in a 2:1 ratio into group A, which received DNP one tablet twice a day for one day; and group B, which received Coartem/Riamet four tablets twice a day for 3 days. The cure rates at 28-day were 99% and 97% in group A and group B, respectively. No serious adverse events occurred. We concluded that both DNP and Coartem/ Riamet were safe, well tolerated and highly efficacious in the treatment of acute uncomplicated falciparum malaria in Thailand.

Adolescent↗

Characterization of chemokine receptor expression and cytokine production in circulating CD4+ T cells from patients with atopic dermatitis: up-regulation of C-C chemokine receptor 4 in atopic dermatitis.

BACKGROUND: Th2 and Th1 cells have been suggested to express CCR3/CCR4 and CCR5/CXCR3, respectively. OBJECTIVE: We examined CCR3, CCR4, CCR5 and CXCR3 expression and cytokine production in peripheral blood CD4+ T cells from patients with atopic dermatitis (AD), which has been postulated to be a Th2-type cell-mediated disease, and then analysed the possible correlation between these values and the levels of several clinical parameters. METHODS: Intracellular cytokine production and chemokine receptor expression in peripheral blood CD4+ T cells from 40 AD patients and 20 sex- and age-matched healthy control subjects were studied by flow cytometry. RESULTS: The frequencies of IL-4- and IL-13-producing CD4+ T cells from patients with AD were significantly higher than those from healthy control subjects (IL-4:3.9 +/- 2.1% vs. 1.6 +/- 0.7%, P = 0.0005, IL-13:4.0 +/- 2.1% vs. 1.8 +/- 0.8%, P = 0.0023), whereas the frequencies of IL-2- and IFN-gamma-producing CD4+ T cells were significantly decreased in AD patients (IL-2:38.1 +/- 10.3% vs. 51.3 +/- 6.3%, P = 0.0003, IFN-gamma: 9.9 +/- 3.5% vs. 26.4 +/- 4.6%, P < 0.0001). The percentage of CCR4+ cells in CD4+ CD45RO+ T cells in AD patients was significantly higher than that in healthy control subjects (24.4 +/- 8.0% vs. 10.9 +/- 2.3%, P < 0.0001) and was correlated positively with the total serum IgE, serum lactic dehydrogenase (LDH) level, eosinophil number, eruption score, and IL-4 and IL-13 secretion in CD4+ T cells, and inversely with IL-2 and IFN-gamma secretion in CD4+ T cells. In contrast, CCR3 was not detected on circulating CD4+ T cells even in AD patients. On the other hand, the percentage of CCR5+ or CXCR3+ cells in CD4+ CD45RO+ T cells in AD patients was significantly decreased (CCR5:23.2 +/- 7.0% vs. 28.4 +/- 5.4%, P = 0.023, CXCR3:29.9 +/- 11.4% vs. 38.5 +/- 6.7%, P = 0.028) and was positively correlated with eruption score (P < 0.05). Multiple regression analyses showed that the percentage of CCR4 expression highly correlated with serum IgE, LDH, eosinophil number and eruption in AD patients. CONCLUSION: CCR4+ cells might be involved in the aetiopathogenesis of AD.

Adolescent↗

[Relationship between the prevalence of hepatic milk spots in pig and the egg density of Ascaris suum in Kitakyushu Municipal Meat Inspection and Control Center].

The hepatic milk spots of pigs are chronic interstitial hepatitis, and are caused by the migration of pig ascarid worm, Ascaris suum, into the liver. A large number of livers are condemned in meat inspection centers as defective food once they are found to have developed milk spots, and thus the economic loss is great. Eggs of Ascaris suum from 120 caecum feces of slaughtered pigs were detected by the nylon mesh filtration (Makiya) technique and they were related to the condemnation data of the milk spot livers in Kitakyushu Municipal Meat Inspection and Control Center from April 2000 to February 2001. The condemnation rate was continuously more than 50% at some particular pig farms, the average rate being as high as 73% during this period. Liver milk spots and Ascarid infection from some 200 mg of caecum feces sampled with the template of the filtration technique were compared. As a result, a close agreement was observed between the two kinds of positive data, and a significant correlation was expected between the average egg density (EPG) of sampled pigs and the prevalence rate of milk spots of the same groups. These results proved that this filtration technique can be used as an effective inspection method for detecting milk spot liver.

Abattoirs↗

Biochemical characterization of cholesterol-3-sulfate as the sole effector for the phosphorylation of HMG1 by casein kinase I in vitro.

Phosphorylation of high mobility group protein 1 (HMG1) by casein kinase I (CK-I) and potent effectors (inhibitors and activators) of this phosphorylation were investigated in vitro. We found that (i) CK-I phosphorylates specifically threonine residues on HMG1 when incubated with cholesterol-3-sulfate (CH-3S), but no phosphorylation of HMG1 is detected in the presence of other cholesterol related compounds or their sulfated derivatives; (ii) this phosphorylation is selectively inhibited by heparin, but stimulated significantly by 3',4',7-trihydroxy-isofavone at low doses (0.1-3 microM); and (iii) CH-3S directly induces a drastic conformational change in HMG1. The latter finding provides a mechanism to explain how CH-3S alone can induce the phosphorylation of HMG1 by CK-I in vitro.

Animals↗

No parallel relationship between nitric oxide production and wet dog shakes susceptible to nitric oxide synthase inhibitors following systemic administration of paraquat in rats.

Shaking behavior, so-called wet dog shakes (WDS), in rats is characteristic behavior indicating morphine abstinence in morphine-dependence and central excitation in relation to seizures elicited by chemicals or electrical stimulation. We have found that paraquat (PQ), a nonselective herbicide, administered systemically to rats induces WDS in a dose-dependent manner. PQ-induced WDS are suppressed by nitric oxide (NO) synthase (NOS) inhibitors, but this suppression is not reversed by an NO precursor, L-arginine (L-Arg). The present study was performed to determine whether the NO system is associated with PQ-induced WDS in rats. A time-course study on the frequency of WDS for each 30-min period up to 120 min after PQ administration (70 mg/kg, s.c.) revealed that significant induction of WDS occurred during the first and second 30-min periods, that is within 60 min of PQ administration. A nonselective NOS inhibitor, Nomega-nitro-L-arginine (L-NA; 30 mg/kg, i.p.), reduced the frequency of the PQ-induced WDS during both of these periods, but the reduced frequency was not reversed by L-Arg (500 mg/kg, i.p.) in either period. Significant induction of WDS occurred when PQ (50 nmol) was administered directly into the ventral or dorsal hippocampus, but not when administered into the amygdala or the caudate putamen, indicating that the hippocampus plays an important role in PQ-induced WDS. The WDS after the administration of PQ into the dorsal hippocampus was significantly suppressed by pretreatment with L-NA (30 mg/kg, i.p.). The extracellular levels of nitrite (NO2-) and nitrate (NO3-), the oxidative products of NO, in the dorsal hippocampus determined by in vivo microdialysis, were stimulated after systemic PQ administration (70 mg/kg, s.c.) in urethane-anesthetized rats. The increases in extracellular NO2- and NO3- were inhibited by L-NA (30 mg/kg, i.p.), and this inhibition was partly reversed by L-Arg (500 mg/kg, i.p.). The increases in extracellular NO2- and NO3- in the dorsal hippocampus appeared 60 min after PQ administration, when the WDS had occurred and disappeared. These findings suggest that NO production in the hippocampus plays a minor role in PQ-induced WDS in rats and that the suppression of PQ-induced WDS by NOS inhibitors might be mediated though complex mechanisms in the brain.

Animals↗

Genetic relatedness and variability in inbred and wild populations of the solitary ascidian Ciona intestinalis revealed by arbitrarily primed polymerase chain reaction.

As the first step in the establishment of inbred Ciona intestinalis strains, the genetic backgrounds of several local populations were evaluated on the basis of comparing 313 random amplified polymorphic DNA (RAPD) loci. Cluster analyses of individuals indicated that this species has local genetic characteristics, although various genetic distances among the populations were relatively low. The bulked RAPD analyses revealed that populations from Torihama and from Onagawa were the most distantly related among the 7 populations examined, suggesting that these two populations are the best candidates for outbreeding. Successive inbreeding in the laboratory was achieved using the Onagawa population. Although the genetic similarity of the F(4) progeny became distinctly higher than that of natural populations, F(5) progeny did not survive, presumably owing to homozygous lethal alleles.

Journal Article↗

Molecular characterization of a 2-Cys peroxiredoxin from the human malaria parasite Plasmodium falciparum.

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.

Amino Acid Sequence↗

Antibodies specific for heat shock proteins in human and murine malaria.

Heat shock proteins (HSPs) are immunodominant antigens recognized by the host immune system in various infectious diseases. We analyzed HSP-specific antibodies, including immunoglobulin G (IgG), IgM and IgA, in sera from malaria patients in Thailand by using an enzyme-linked immunosorbent assay. All of the antibodies to HSP90 were remarkably increased in the patients compared with those in controls, while only IgM to HSP70 or IgA to HSP65 was significantly elevated. Further experiments showed that anti-HSP IgG was significantly increased in C57BL/6 mice infected with a non-lethal strain of Plasmodium yoelii, with anti-HSP90 IgG being the most elevated. These results suggest that the antigenic potential of HSP90 is higher than those of HSP70 and HSP65 in malaria infection.

Animals↗

Variation of incubation time in an in vitro drug susceptibility test of Plasmodium falciparum isolates studied in the Solomon Islands.

A study on chloroquine resistance of falciparum malaria was conducted in the Solomon Islands. Both in vitro and clinical tests were performed. In our regular studies of in vitro chloroquine susceptibility tests on Plasmodium falciparum from non-immuners in Japan, the threshold point to differentiate resistant and susceptible isolates was set at a 0. 114 microM chloroquine in the semi-micro culture system, and this point was also applicable in the study of the malaria parasite taken in the highly endemic malarious area with good coincidence with clinical observation. Variation in the incubation time (24-63) to reach the schizont stage of the isolated parasites were noted. It appeared that chloroquine resistant P. falciparum showed traits to reach the schizont stage within a shorter incubation period.

Animals↗

Sudden death caused by tension pneumothorax after rupture of a thoracic aortic aneurysm. Case report.

A rare case of fatal tension pneumothorax is reported. An aged Japanese man with marked subcutaneous emphysema of the neck was found collapsed in a betting office. He was ascertained to have left tension pneumothorax, based on radiographic examinations carried out before his death. At autopsy, severe pneumomediastinum was observed, and the descending thoracic aorta with a ruptured dissecting aneurysm was closely adhered to the left lung pleura. The hemorrhage spread into the pulmonary parenchyma and finally spouted out from the surface of the lung apex. Because the blood loss itself was not fatal in quantity, it is concluded that the patient died of tension pneumothorax caused by a lung penetration from the rupture of an aortic aneurysm.

Aged↗

[A case of falciparum malaria successfully treated with intravenous artesunate].

The case was a 47-year-old Nigerian male who was thought to have contracted malaria in Nigeria and then manifested fever with chill, arthralgia and diarrhea in Japan. The blood test at International Medical Center of Japan revealed thrombocytopenia and anemia. Ring forms of 0.03% of his RBCs and ICT Malaria P.f/P.v test was also positive for Plasmodium falciparum. We prescribed mefloquine to him, but the number of the paresites in his peripheral blood did not decrease, and, in fact, they came to increase (maximum 6.66%) 20 hours after the drug treatment. As clinical condition of malaria were liable to change seriously, intravenous Artesunate (a qinghaosu derivative) was decided to be given additionally to the patient. Consequently the parasites disappeared in 20 hours from his blood but a low grade fever still continued possibly because of cholecystitis. At the same time of Artesunate treatment, hemoglobinuria started and anemia worsened partly because of his G-6-PD deficiency. All pending problems were improved by the time he left Japan and those parasites were finally found to be susceptible for mefloquine by the in vitro susceptibility test. This is the first reported case of falciparum malaria successfully treated with intravenous Artesunate in Japan.

Antimalarials↗

Variation in malaria endemicity in relation to microenvironmental conditions in the Admiralty Islands, Papua New Guinea.

For 197 adults and adolescents in four villages of three small islands in the Admiralty Islands, Papua New Guinea, antimalarial antibody titers were examined using the indirect fluorescent antibody test (IFAT) and malaria parasites were detected by the microtiter plate hybridisation (MPH) method using polymerase chain reaction (PCR) technique. The parasite rate (either Plasmodium falciparum or P. vivax, or both) averaged 39.2%, varying from 31.1% to 44.8% among the four villages due to natural and artificial microenvironmental conditions related to breeding sites of mosquitoes (Anopheles farauti). The lack of flat zones owing to geomorphological formation contributed to the lowest parasite rate in the extremely small island. However, human-modified environments such as a wet-land (naturally formed but artificially reformed) and an open well played significant roles in other inter-village differences. The present findings imply significant roles of microenvironment in diversified malaria prevalence and suggest some ways of mitigation of malarial hazards.

Adolescent↗