Therapeutic efficacy of artesunate in Plasmodium vivax malaria in Thailand.

Our previous study showed that in vitro susceptibility of Plasmodium vivax to chloroquine has significantly decreased in Thailand within the past two decades. Thus, the evaluation of alternative antimalarials for treatment of vivax malaria is needed. The aim of this study was to examine parasitological and clinical efficacy of an artemisinin derivative (artesunate) for the treatment of vivax malaria in patients who were admitted to the Bangkok Hospital for Tropical Diseases. We randomly allocated patients aged 12-56 years to receive 3.3mg/kg (adult dose 200 mg) on the first day, and for the next four days each patient was given 1.65 mg/kg orally (adult dose 100 mg), total dose = 600 mg. After the five-day course of artesunate, primaquine was given: a single oral dose of 15mg for 14 days. A total number of 42 patients received treatment. All participants were followed up for 28 days. In all the cases, both parasitemia and fever were resolved rapidly; the mean fever clearance time and parasite clearance time, 14.6 and 36.7 hours, respectively, showed that therapeutic response to artesunate was better than that of chloroquine. The 14-day cure rate was 100%, but reappearance of parasitemia was seen in two patients on days 21 and 25 following treatment, respectively. These two cases of failure rate should be considered as true relapse rather than recrudescence, since the relapse interval in Southeast Asian vivax malaria according to recent findings seems to be 3 weeks after start of treatment, if primaquine is not given or an inadequate amount is given. In conclusion, artesunate might be useful in treatment of vivax malaria, causing a good blood schizontocidal effect. However, to prevent emerging resistance it should never be used alone.

Liquid chromatographic-atmospheric pressure chemical ionization mass spectrometric analysis of opiates and metabolites in rat urine after inhalation of opium.

To examine the urinary excretion of opiates and their metabolites following inhalation exposure of rats to opium, analytical procedures for the simultaneous determination of the compounds in opium, the vapor derived by the volatilization of opium and the urine of rats exposed to the opium vapor were developed using liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (LC-APCI-MS). Seven compounds were determined in the opium, namely morphine, codeine, thebaine, noscapine, papaverine, meconic acid and meconin. All seven were extracted with 2.5% acetic acid solution and subjected to LC-APCI-MS analysis. The separation was performed on an ODS column in acetonitrile-50 mM ammonium formate buffer (pH 3.0) using a linear gradient program and quantitative analysis was carried out in the selected ion monitoring mode ([M+H](+)). For the analysis of the volatilization of opium, the opium (1 g) was added to a glass pipe, which was then heated at 300 degrees C for 20 min. Negative pressure (air flow-rate; 300 ml/min) was used to draw the vapor through a series of glass wool and methanol traps. The total amount of each compound in the vapor was estimated by measurement of the compounds trapped in the glass wool and methanol. Wister rats (n=3) were exposed to the vapor derived from the volatilization system and the urinary amounts (0-72 h) of the six opiates and metabolites including morphine-3-grucronide (M3G) and morphine-6-grucronide (M6G) were measured after solid-phase extraction. The calibration curves for those compounds in the rat urine were linear over the concentration range 10-500 ng/ml. The recoveries for each analyte from the rat urine sample spiked with standard solution were generally greater than 80%, and the relative standard deviation for the analytical procedure was less than 8% with the exception of meconin. After inhalation exposure of rats to opium, M3G (5.45-14.38 micro g), morphine (2.27-4.65 micro g), meconin (0.54-1.85 micro g), codeine (0.54-1.85 micro g), noscapine (0.34-0.40 micro g) and papaverine (0.01-0.04 micro g) were detected in the urine over 72 h. However, only trace levels of thebaine were observed despite it being one of the major alkaloids found in the opium. On the other hand, a relatively large amount of meconin was detected in the vapor and the urine as compared with the opium. It is suggested that the presence of meconin in biological fluids could be indicative of opium ingestion by inhalation.

Stage-specific isoforms of Ascaris suum complex. II: The fumarate reductase of the parasitic adult and the succinate dehydrogenase of free-living larvae share a common iron-sulfur subunit.

Complex II of adult Ascaris suum muscle exhibits high fumarate reductase (FRD) activity and plays a key role in anaerobic electron-transport during adaptation to their microaerobic habitat. In contrast, larval (L2) complex II shows a much lower FRD activity than the adult enzyme, and functions as succinate dehydrogenase (SDH) in aerobic respiration. We have reported the stage-specific isoforms of complex II in A. suum mitochondria, and showed that at least the flavoprotein subunit (Fp) and the small subunit of cytochrome b (cybS) of the larval complex II differ from those of adult. In the present study, complete cDNAs for the iron-sulfur subunit (Ip) of complex II, which with Fp forms the catalytic portion of complex II, have been cloned and sequenced from anaerobic adult A. suum, and the free-living nematode, Caenorhabditis elegans. The amino acid sequences of the Ip subunits of these two nematodes are similar, particularly around the three cysteine-rich regions that are thought to comprise the iron-sulfur clusters of the enzyme. The Ip from A. suum larvae was also characterized because Northern hybridization showed that the adult Ip is also expressed in L2. The Ip of larval complex II was recognized by the antibody against adult Ip, and was indistinguishable from the adult Ip by peptide mapping. The N-terminal 42 amino acid sequence of Ip in the larval complex II purified by DEAE-cellulofine column chromatography was identical to that of the mature form of the adult Ip. Furthermore, the amino acid composition of larval Ip determined by micro-analysis on a PVDF membrane is almost the same as that of adult Ip. These results, together with the fact, that homology probing by RT-PCR, using degenerated primers, failed to find a larval-specific Ip, suggest that the two different stage-specific forms of the A. suum complex II share a common Ip subunit, even though the adult enzyme functions as a FRD, while larval enzyme acts as an SDH.

Antimalarial activity of extracts of Malaysian medicinal plants.

In vitro and in vivo studies revealed that Malaysian medicinal plants, Piper sarmentosum, Andrographis paniculata and Tinospora crispa produced considerable antimalarial effects. Chloroform extract in vitro did show better effect than the methanol extract. The chloroform extract showed complete parasite growth inhibition as low as 0.05 mg/ml drug dose within 24 h incubation period (Andrographis paniculata) as compared to methanol extract of drug dose of 2.5 mg/ml but under incubation time of 48 h of the same plant spesies. In vivo activity of Andrographis paniculata also demonstrated higher antimalarial effect than other two plant species.

(2E,6R)-8-hydroxy-2,6-dimethyl-2-octenoic acid, a novel anti-osteoporotic monoterpene, isolated from Cistanche salsa.

(2E,6R)-8-Hydroxy-2,6-dimethyl-2-octenoic acid [(R)-HDOA], a novel monoterpene from Cistanche salsa, a Chinese herb, was found to be an anti-osteoporotic compound. The extract of Cistanche salsa significantly suppressed the bone weight loss in ovariectomized mice, a postmenopausal osteoporosis model. The active substance was then purified by using this osteoporotic model and the chemical structure was determined. The active compound from Cistanche salsa, (R)-HDOA, suppressed the decrease of bone weight and the mechanical strength in the ovariectomized mice. Furthermore, (R)- and (S)-HDOA were synthesized and the activity of each was evaluated. (R)-HDOA suppressed the bone weight loss, although (S)-HDOA did not showed any activity.

Possible associations of rectal carcinoma with Schistosoma japonicum infection and membranous nephropathy: a case report with a review.

We report the first case of rectal carcinoma associated with S. japonicum and membranous nephropathy. A 57-year-old Japanese man noticed narrowing of his feces. He had lived in Yamanashi prefecture, an endemic area of S. japonicum. He had suffered from nephrotic syndrome for about 1 year. Barium enema study showed a severe stricture in the upper rectum and biopsy specimens from the tumor demonstrated well differentiated adenocarcinoma and many ova of S. japonicum. Sonography of the liver showed a network pattern and a linear high echoic area. Low anterior resection with incisional biopsy of the liver and the right kidney was performed. Histopathological findings showed well differentiated adenocarcinoma and schistosomal ova. The total number of ova in the resected colon amounted to 15,133, consisting of 2243 inside and 12,890 outside the carcinoma. The nearer to the carcinoma the area was, the higher was the density of ova. The findings of light microscopy and electron microscopy of the biopsy specimen from the kidney were compatible with membranous nephropathy (stage II). This case suggests that schistosomal ova have some effect on carcinogenesis and nephrotic syndrome. In patients with nephrotic syndrome of unknown cause, especially in inhabitants of endemic areas of S. japonicum, gastrointestinal malignancy should be ruled out as an etiological factor. Sigmoidoscopy would be useful for colorectal carcinoma surveillance in S. japonicum patients.

BAZF, a novel Bcl6 homolog, functions as a transcriptional repressor.

The BCL6 gene, which has been identified from the chromosomal translocation breakpoint in B-cell lymphomas, functions as a sequence-specific transcriptional repressor. We cloned a novel Bcl6-homologous gene, BAZF (encoding Bcl6-associated zinc finger protein). The predicted amino acid sequence of BAZF indicated that the BTB/POZ domain and the five repeats of the Krüppel-like zinc finger motif are located in the NH2-terminal region and the COOH-terminal region, respectively. BAZF associated with Bcl6 at the BTB/POZ domain and localized in the nucleus. Since zinc finger motifs of BAZF were 94% identical to those of Bcl6 at the amino acid level, BAZF bound specifically to the DNA-binding sequence of Bcl6 and functioned as a transcriptional repressor. The repressor activity was associated with both the BTB/POZ domain and the middle portion of BAZF. The 17-amino-acid sequence in the middle portion was completely conserved between BAZF and Bcl6, and the conserved region was critical for the repressor activity. Expression of BAZF mRNA, like that of Bcl6 mRNA, was induced in activated lymphocytes as an immediate-early gene. Therefore, the biochemical character of BAZF is similar to that of Bcl6 although the tissue expression pattern of BAZF differs from that of Bcl6. This is apparently the first report of a gene family whose members encode zinc finger proteins with the BTB/POZ domain.

Therapeutic effects of water-soluble echinocandin compounds on Pneumocystis pneumonia in mice.

The therapeutic effectiveness of water-soluble echinocandin compounds obtained from Coleophoma empetri F-11899, which has a strong inhibitory effect on the growth of fungi, was examined in nude mice with experimental Pneumocystis pneumonia. The studies demonstrated the potential usefulness of the compounds.

Effects of Shimotsu-to on the microcirculation of the bulbar conjunctiva and hemorheological parameters in normal subjects.

The effects of 'Shimotsu-to' (Si-Wu-Tang in Chinese), one of the most important prescriptions for 'ketsukyo' and 'oketsu' syndrome in traditional Chinese medicine, on the microcirculation of bulbar conjunctiva and the hemorheological parameters were examined in ten healthy volunteers. After one hour of oral administration of Shimotsu-to extract, the blood flow rate and the blood flow volume significantly increased and the DEA (maximum diameter of the column of intravascular erythrocyte aggregation) decreased. The whole blood viscosity declined at middle and high shear rates, but both the plasma viscosity and the erythrocyte deformability were not effected. These results suggest that Shimotsu-to has a salutary effect on the microcirculation through a decrease in the whole blood viscosity.

Preventive effects of saponins from puerariae radix (the root of Pueraria lobata Ohwi) on in vitro immunological injury of rat primary hepatocyte cultures.

The preventive effects of saponins from Puerariae Radix toward in vitro immunological liver injury using an antiserum against the rat liver plasma membranes on primary cultured rat hepatocytes were studied. Crude saponin from Puerariae Radix inhibited the elevation of alanine aminotransferase (ALT) activity at the dose of 90 micrograms/ml. The inhibition was stronger than that of glycyrrhizin, which was a positive control drug. The representative saponins in this drug, soyasaponin I and kudzusaponin SA3, were also more effective than glycyrrhizin, although their effects were weaker than that of crude saponin at the lower doses (90, 200 micrograms/ml). At 500 micrograms/ml, kudzusaponin SA3 showed antihepatotoxic activity equal to that of crude saponin.

Autoimmune hepatitis triggered by administration of an herbal medicine.

Although herbal medicines are believed to be safe with few side effects, there are several reports on drug-induced liver injury caused by them. However, there are no reports of autoimmune hepatitis triggered by herbal medicines. We report here the case of a patient with autoimmune hepatitis that became clinically apparent after administration of Dai-saiko-to (Da-Chai-Hu-Tang), an herbal medicine that is used as a standard medicine in Japan.

[Prolonged antegrade amnesia due to left anterior thalamic infarct, and SPECT findings].

A 60-year-old right-handed man developed disorientation, antegrade amnesia and transient mild clouding of consciousness. The antegrade amnesia persisted for more than one year after its onset. T2-weighted MR images showed high signal intensity in the left anteromedial thalamus. 99mTc-HM-PAO SPECT revealed decreased uptake in the left frontal and temporal lobes. These SPECT findings were still observed a year later. These findings suggest that functional involvement of the frontal and temporal lobe connections with the dorsomedial nucleus, anterior nucleus, and the mamillothalamic tract in the anteromedial part of thalamus were responsible for the prolonged antegrade amnesia. We think that SPECT findings are important for evaluating the outcome of thalamic amnesia.

Cytochrome b in human complex II (succinate-ubiquinone oxidoreductase): cDNA cloning of the components in liver mitochondria and chromosome assignment of the genes for the large (SDHC) and small (SDHD) subunits to 1q21 and 11q23.

Complex II (succinate-ubiquinone oxidoreductase) is an important enzyme complex in both the tricarboxylic acid cycle and the aerobic respiratory chains of mitochondria in eukaryotic cells and prokaryotic organisms. In this study, the amino acid sequences of the large (cybL) and small (cybS) subunits of cytochrome b in human liver complex II were deduced from cDNAs isolated by homology probing with mixed primers for the polymerase chain reaction. The mature cybL and cybS contain 140 and 103 amino acids, respectively, and show little similarity to the amino acid sequences of the subunits from other species in contrast to the highly conserved features of the flavoprotein (Fp) subunit and iron-sulfur protein (Ip) subunit. From hydrophobicity analysis, both cybL and cybS appear to have three transmembrane segments, indicating their role as membrane-anchors for the enzyme complex. Histidine residues, which are possible heme axial ligands in cytochrome b of complex II, were found in the second transmembrane segment of each subunit. The genes for cybL (SDHC) and cybS (SDHD) were mapped to chromosome 1q21 and 11q23, respectively by fluorescent in situ hybridization (FISH).

Chemical nature of the light emitter of the Aequorea green fluorescent protein.

The jellyfish Aequorea victoria possesses in the margin of its umbrella a green fluorescent protein (GFP, 27 kDa) that serves as the ultimate light emitter in the bioluminescence reaction of the animal. The protein is made up of 238 amino acid residues in a single polypeptide chain and produces a greenish fluorescence (lambda max = 508 nm) when irradiated with long ultraviolet light. The fluorescence is due to the presence of a chromophore consisting of an imidazolone ring, formed by a post-translational modification of the tripeptide -Ser65-Tyr66-Gly67-. GFP has been used extensively as a reporter protein for monitoring gene expression in eukaryotic and prokaryotic cells, but relatively little is known about the chemical mechanism by which fluorescence is produced. To obtain a better understanding of this problem, we studied a peptide fragment of GFP bearing the chromophore and a synthetic model compound of the chromophore. The results indicate that the GFP chromophore consists of an imidazolone ring structure and that the light emitter is the singlet excited state of the phenolate anion of the chromophore. Further, the light emission is highly dependent on the microenvironment around the chromophore and that inhibition of isomerization of the exo-methylene double bond of the chromophore accounts for its efficient light emission.

Comparative effects of chelating agents on pulmonary toxicity of systemic nickel in mice.

N-Benzyl-D-glucaminedithiocarbamate (BGD), diethyldithiocarbamate (DDTC), dihydroxyethyldithiocarbamate (DHED), trans-1,2-cyclohexanediamine N,N,N',N'-tetraacetic acid (CDTA) and meso-2,3-dimercaptosuccinic acid (DMSA) were studied for their protective effects against the pulmonary toxicity in mice induced by acute exposure to nickel. Nickel injection increased lipid peroxidation, lactate dehydrogenase (LDH) activity and the concentrations of protein, phospholipids (PL) and essential metals such as Ca, Fe and Zn and decreased the reduced glutathione (GSH) concentration and alkaline phosphatase (ALP) activity in the lungs. At 30 min after Ni treatment, DMSA, BGD and DDTC effectively depressed Ni concentration in the lungs. At 24 h after Ni treatment, DMSA and BGD were effective in mobilizing Ni from the lungs. Both DMSA and BGD significantly prevented increases in lipid peroxidation and in the concentrations of PL, Ca, Fe and Zn, and decreases in GSH concentration and ALP activity in the lungs of mice caused by Ni injection. Treatment with DMSA or BGD was more effective than that with other chelating agents in decreasing the pulmonary Ni concentration and preventing other changes caused by acute exposure to Ni, resulting in effective protection against Ni-induced pulmonary damage.

Inhibitory effects of traditional Chinese medicine Shimotsu-to and its included crude fractions on adjuvant-induced chronic inflammation of mice.

Effects of a traditional Chinese medicine, Shimotsu-to (a combined prescription of cnidium rhizome, peony root, angelica root and rehmannia root), and its included crude fractions were investigated on an adjuvant-induced chronic inflammation model of mice. The aqueous extract (30, 100 and 300 mg/kg, i.p.) of Shimotsu-to reduced the carmine content, granuloma weight, inflammation cell count and pouch fluid weight in the inflammation model, respectively. The extract of Shimotsu-to without cnidium at the same doses did not produce significant changes in these four inflammatory parameters. The same doses of extracts of Shimotsu-to without peony, and without angelica, weakly reduced these parameters, except for pouch fluid weight. The extract (30, 100 and 300 mg/kg) of cnidium significantly reduced these four parameters. The same doses of peony extract reduced carmine content, granuloma weight and pouch fluid weight, but less than those of the cnidium extract. The extract of cnidium and peony at the same doses reduced in an additive manner these inflammatory parameters in their combination. These results demonstrated that the Shimotsu-to extract reduced angiogenesis, granuloma formation, inflammatory cell migration and pouch fluid exudation in the adjuvant-induced chronic inflammation model. Cnidium represented the main ingredient for producing the anti-chronic inflammatory effects of Shimotsu-to extract. Cnidium and peony exhibited additive anti-inflammatory effects in combination.

Comparison of first-line antihypertensive drugs by a randomized cross-over method--a preliminary report.

The present study was undertaken to compare the effects of first-line antihypertensive drugs in Japanese patients. Four antihypertensive drugs were studied: trichlormethiazide (TCT), nifedipine retard (NIF), atenolol (ATN), and enalapril malate (ENP). Thirty-eight patients (16 men and 22 women; age, 53.3 +/- 8.8 years, mean +/- SD) were enrolled in the study. After a control period of 2 to 4 weeks, the four drugs were administered according to a randomized, cross-over design, the duration of each treatment period being 8 to 12 weeks. The initial dose of each drug was increased until blood pressure (BP) fell to less than 150/90 mmHg. The maximum doses of TCT, NIF, ATN, and ENP were 4, 40, 50, and 20 mg/day, respectively. The protocol was completed in 25 of the 38 patients. The BPs (SBP/DBP) at the end of each period were 168 +/- 3 (mean +/- SEM)/105 +/- 1 (control), 149 +/- 4/ 98 +/- 2 (TCT), 138 +/- 3/89 +/- 2 (NIF), 151 +/- 4/94 +/- 2 (ATN), and 152 +/- 4/97 +/- 2 mmHg (ENP). The BP during NIF treatment was significantly lower than during the other treatments. This finding suggests that the calcium antagonist had a greater hypotensive effect than the other first-line antihypertensive drugs studied. The subjects seem to more closely resemble black rather than white populations with respect to their response to antihypertensive treatment.

Comparative effects of diethyldithiocarbamate and N-benzyl-D-glucamine dithiocarbamate on cis-diamminedichloroplatinum-induced toxicity in kidney and gastrointestinal tract in rats.

Sodium diethyldithiocarbamate (DDTC) and sodium N-benzyl-D-glucamine dithiocarbamate (BGD) were compared for their protective effects against cis-diamminedichloroplatinum (DDP)-induced toxicity in kidney and gastrointestinal tract in rats. Rats were injected i.p. with the dithiocarbamates (2.0 mmol kg-1) immediately or 1 h after i.v. injection of DDP (20 mumol kg1). Treatment with BGD immediately or at 1 h after DDP injection effectively prevented the nephrotoxicity of DDP, but administration of DDTC immediately or 1 h after DDP afforded little protection. N-Benzyl-D-glucamine dithiocarbamte significantly reversed the reduction in maltase, sucrase and aminopeptidase activities of jejunal mucosa of rats treated with DDP, whereas treatment with DDTC concurrent with DDP could not reverse the reduction in disaccharidase activity following DDP injection. The platinum concentrations in liver and kidney were significantly decreased by treatment with BGD and DDTC. The treatment with DDTC at 1 h after DDP was more effective on the reduction of platinum concentrations in these tissues than that immediately after DDP. There was no difference between the renal and hepatic concentrations of platinum in two time intervals of BGD. The pharmacokinetic studies indicated that DDTC is more rapidly metabolized than BGD, resulting in larger total clearance and elimination rate constant values. These results reveal that the administration of BGD immediately and at 1 h after DDP can protect against the renal and gastrointestinal toxicities caused by DDP, whereas DDTC afforded little protection, and that the time interval between administration of DDP and DDTC greatly influences its protective effect on DDP-induced toxicity, indicating that the chelation therapy of BGD for DDP is superior to that of DDTC.

Comparative study and cDNA cloning of the flavoprotein subunit of mitochondrial complex II (succinate-ubiquinone oxidoreductase: fumarate reductase) from the dog heartworm, Dirofilaria immitis.

Mitochondrial complex II functions as a fumarate reductase (FRD), the reverse reaction of succinate dehydrogenase (SDH), and plays an important role in the anaerobic respiratory chain of parasitic helminths. In this study, complex II from the dog heartworm, Dirofilaria immitis adult, which is thought to act as a homolactatic fermenter, was examined in terms of its enzymatic features and primary structure in order to investigate the possible role of mitochondria in this filaria. Mitochondria from D. immitis adult showed high FRD activity when the enzymatic assay was performed using methylviologen as an artificial electron donor. The ratio of SDH to FRD in D. immitis was comparable to that in Ascaris suum adult, which is known to have an anaerobic mitochondrial respiratory chain with a high FRD activity of complex II. The FRD activity of D. immitis mitochondria was inhibited by the sulfhydryl reagent N-ethylmaleimide (NEM), while that of A. suum complex II was resistant to this inhibitor. The presence of the flavoprotein (Fp) subunit, which contains the substrate binding active site, was confirmed in D. immitis mitochondria by immunoblotting using a monoclonal antibody against the A. suum Fp subunit. By homology probing with the polymerase chain reaction, the entire cDNA for the D. immitis adult Fp was cloned and sequenced. The deduced amino acid sequence showed significant homology to that of A. suum and other mitochondrial Fps, in contrast to much less similarity to bacterial FRD, even though the D. immitis complex II showed high FRD activity. These results are the first indication of the presence of a functional complex II in D. immitis mitochondria.

The utility of chelating agents as antidotes for nephrotoxicity of gold sodium thiomalate in adjuvant-arthritic rats.

The effects of 2,3-dimercaptopropane sulphonate (DMPS) and N-(2-mercapto-2-methylpropanoyl)-L-cysteine (bucillamine) against the renal damage induced by gold sodium thiomalate (AuTM) in adjuvant-arthritic rats were studied. Arthritic rats induced by adjuvant using Mycobacterium butyricum were injected intraperitoneally with a chelating agent (0.6 mmol/kg) immediately after intramuscular injection of AuTM (0.066 mmol/kg) every other day for 21 days. Treatment with DMPS and bucillamine prevented increases in the urinary excretion of protein, aspartate aminotransferase, and glucose and blood urea nitrogen level after AuTM injection. AuTM prevented the increase in both adjuvant-injected and uninjected hind-feet volumes. The prevention of these inflamed lesions by AuTM was not affected by DMPS and bucillamine. These chelating agents decreased the gold concentration in the kidney and liver after AuTM administration, but did not affect the hepatic and renal concentrations of copper, zinc, iron, and calcium except the renal copper level after AuTM. These findings suggest that DMPS and bucillamine are very useful antidotes for gold toxicity.