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C Fuke

Publications and source records attributed to C Fuke.

32 records · Page 2Linked to original sources
PubMed1992

Regional brain distribution of toluene in rats and in a human autopsy.

Toluene concentrations in 9 brain regions of acutely exposed rats and that in 11 brain regions of a human case who inhaled toluene prior to death are described. After exposure to toluene by inhalation (2000 or 10,000 ppm) for 0.5 h or by oral dosing (400 mg/kg), rats were killed by decapitation 0.5 and 4 h after onset of inhalation and 2 and 10 h after oral ingestion. After each experimental condition the highest range of brain region/blood toluene concentration ratio (BBCR) was in the brain stem regions (2.85-3.22) such as the pons and medulla oblongata, the middle range (1.77-2.12) in the midbrain, thalamus, caudate-putamen, hypothalamus and cerebellum, and the lowest range (1.22-1.64) in the hippocampus and cerebral cortex. These distribution patterns were quite constant. Toluene concentration in various brain regions were unevenly distributed and directly related blood levels. In a human case who had inhaled toluene vapor, the distribution among brain regions was relatively similar to that in rats, the highest concentration ratios being in the corpus callosum (BBCR: 2.66) and the lowest in the hippocampus (BBCR: 1.47).

Adult↗
PubMed1992

Effect of acetaldehyde on ethanol absorption in the canine jejunum.

The effects of acetaldehyde on ethanol absorption from the intestinal tract were studied using canine jejunal segment. A thirty-centimeter jejunal segment with intact vascular supply was isolated, and jejunal absorption studies were performed by administering a 17% ethanol solution (0.4 g/kg) into the lumen of the jejunal segment. In the control group, blood ethanol concentrations in the portal vein increased rapidly, with a peak level of 9.8 +/- 1.9 mM 30 min after administration. In the cyanamide-pretreated group, dogs were injected intravenously with cyanamide (100 mg/kg), an inhibitor of acetaldehyde dehydrogenase, 150 min before ethanol dosing. The blood ethanol concentration in the portal vein of this group, accompanied by a high acetaldehyde concentration, increased gradually, reaching a peak of 10.7 +/- 1.84 mM 120 min after ethanol administration. Each concentration gradient corresponded to the systemic circulatory order from the portal vein for ethanol concentration, and from the hepatic vein for acetaldehyde concentration. The absorbed amount of ethanol in the control and cyanamide-pretreated groups was 94.9 +/- 4.1% and 69.3 +/- 4.8%, respectively. Pharmacokinetic analysis indicated that a presence of high acetaldehyde concentration in the blood resulted in less ethanol reaching the systemic circulation (control: 7.34 +/- 2.95 h-1, cyanamide-pretreated: 1.08 +/- 0.75 h-1). The results also suggest that the absorption of ethanol from the intestine decreases when there is a high acetaldehyde concentration in the blood.

Acetaldehyde↗
PubMed1992

[Studies on ethanol absorption from the intestine--blood ethanol and acetaldehyde concentrations in the various vessels].

We describe the concentration gradient of ethanol at different blood sampling sites of dogs dosed via the jejunal segment or intravenously, and the subsequent recovery of intestinal fluid from the jejunal segment. After laparotomy a 30 cm length of jejunal segment with intact vascular supply was isolated. Blood samples were collected from the portal vein, hepatic vein, aorta and inferior vena cava. A 17% ethanol solution was used for a small dose group (0.4 g/kg) and a 33% solution for a large dose group (0.8 g/kg). In the small dose and large dose groups administered the solution via the jejunal segment, ethanol concentration in the blood of the portal vein increased rapidly and the highest ethanol concentration was detected in the portal vein, followed, in descending order by the hepatic vein, aorta and inferior vena cava. The highest acetaldehyde concentration in blood was detected in the hepatic vein, followed by that in the aorta while the lowest was in the portal vein and inferior vena cava in both groups. Each concentration gradient corresponded in order to systemic circulatory order from the intestine (ethanol absorption site) for ethanol concentration, or from the liver (acetaldehyde formation area) for acetaldehyde concentration. There was no difference in ethanol concentration among the four sampling sites in the case of intravenous ethanol injection, but a gradation of acetaldehyde concentration similar to that in the jejunal segment dosed cases was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetaldehyde↗
PubMed1990

IgG subclass distributions of anti-horse serum antibodies and natural venom-antibodies produced in response to antivenom injection or snake bite in humans.

The Japanese Mamushi (Agkistrodon halys blomhoffi, BOIE) is the most common snake in Japan. Bite victims treated with antivenom (horse serum) can produce antibodies against the horse serum and the snake venom. We studied distributions of the IgG subclasses of both these antibodies produced in response to antivenom injection and snake bite. We found that IgG1 and IgG4 of each antibody in the victims' serum were present for a long period of time.

Animals↗
PubMed1990

[The distribution of toluene in the brain and its effects on the brain catecholamines in acute toluene poisoning].

The regional distribution of toluene in the brain and its effects on the brain catecholamine levels in rats is reported. Separate sets of rats were exposed to the toluene via inhalation, at 1,500 ppm and at 10,000 ppm respectively, and via an ingestion (400 mg/kg). Given these three exposure conditions, the values of brain/blood toluene ratios were found to be the highest in the brain stem areas (2.85-3.22) such as the pons and medulla oblongata, in the middle range in the midbrain, the thalamus, the caudate-putamen, the hypothalamus and the cerebellum (1.77-2.12), and in the lowest ranges in the olfactory bulb, the hippocampus and the cerebral cortex (1.22-1.64). The values of the partition coefficient of toluene in the brain regions and in the blood of rats examined in vitro were also the highest in the brain stem and the lowest in the cerebral cortex. The highest values of brain/blood toluene and partition coefficients of toluene in the brain regions and blood were obtained in the lipid-rich regions. These results suggest that toluene, which has a high lipid solubility and no protein binding capability, distributes according to lipid contents of the brain. The inhalation of toluene (1,500 ppm and 10,000 ppm) caused decreases in the noradrenaline (NA) levels in the dorsal part of rat pons, rich in locus coeruleus, and in the dopamine (DA) levels in the hypothalamus and ventral part of the rat midbrain, rich in substantia nigra.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1989

A fatal case of oral ingestion of toluene.

A 51-year-old male ingested orally a large quantity of toluene and died about 30 min later. The presence of toluene in body fluids and tissues was confirmed by gas chromatography and gas chromatography/mass spectrometry. Tissue distribution of toluene showed that the liver detected the highest content of toluene (433.5 micrograms/g), except for the stomach contents, followed by pancreas (88.2 micrograms/g), brain (85.3 micrograms/g), heart (62.6 micrograms/g), blood (27.6 micrograms/g), fat (12.2 micrograms/g) and finally cerebrospinal fluid (11.1 micrograms/g).

Chromatography, Gas↗
PubMedDate not supplied

A rapid and sensitive quantitation of Amitraz in plasma by gas chromatography with nitrogen-phosphorus detection and its application for pharmacokinetics.

We report a simple, sensitive, and rapid quantitation of Amitraz in plasma after Extrelut-3 column extraction by gas chromatography with nitrogen-phosphorus detection (GC-NPD). The plasma sample was diluted four-fold with borate buffer (0.01M, pH 11), put into an Extrelut-3 column, left for 15 min, and then eluted with 15 mL of n-hexane. The n-hexane eluate was evaporated under nitrogen gas flow at room temperature. The residue was reconstituted with 0.1 mL of acetone containing nitrazepam as an internal standard. A 2-microL aliquot was injected into a wide-bore capillary column GC-NPD. The detection limit was 0.5 ng/mL and linearity was obtained in the range of 1-200 ng/mL. Amitraz in the buffer at pH 11 remained stable in a freezer for one week at -20 degrees C. The GC-NPD method was found useful in studying the pharmacokinetics of a single dose intravenous administration of Amitraz to a dog.

Animals↗
PubMedDate not supplied

Simultaneous determination of bromvalerylurea, bromodiethylacetylurea, and allylisopropylacetylurea in serum and urine by high-performance liquid chromatography with a multiwavelength UV detector and thin-layer chromatography.

A method for rapid detection and identification of bromvalerylurea (BVU), bromodiethylacetylurea (BDU), and allylisopropylacetylurea (AIU) in serum and urine by high-performance liquid chromatography (HPLC) with a multiwavelength UV detector after Sep-Pak C18 cartridge extraction is reported. A Jasco Finepak C18 reversed-phase column was used for the separation. Acetonitrile-distilled water (1:1, v/v) was used as a mobile phase. There was no significant absorption of the three hypnotics in the UV spectra (210-350 nm). However, the absorption of each was higher at the shorter wavelengths. The quantifications for the three hypnotics detected at 210 nm by the chromatogram were linear over the range 0.2-4 micrograms/mL and the detection limits of BVU, BDU, and AIU were 5, 10, and 10 ng as absolute amounts, respectively. The mean recovery yields of BVU, BDU, and AIU by Sep-Pak C18 cartridge extraction were 85.7 +/- 4.1, 98.6 +/- 2.2, and 95.1 +/- 3.5% (n = 5) in serum and 79.5 +/- 3.8, 95.7 +/- 1.8, and 93.0 +/- 4.2% (n = 5) in urine, respectively. An optimal system of thin-layer chromatography for the identification of the hypnotics is also discussed.

Bromisovalum↗
PubMedDate not supplied

A rapid, simultaneous determination of paraquat and diquat in serum and urine using second-derivative spectroscopy.

A rapid, simple method based on second-derivative spectroscopy of the simultaneous analysis of paraquat and diquat in serum and urine is described. Paraquat and diquat in serum were deproteinized with sulfosalicylic acid, and those in urine were reduced with NaOH-dithionite solution. A qualitative and quantitative analysis of reduced paraquat and diquat was made at the amplitude peaks of 396-403 nm and 454-464 nm in the second-derivative spectra, respectively. The entire procedure was completed within about 10 minutes for a serum sample and within about 5 minutes for a urine sample. Application of the proposed method on a poisoned patient is also reported.

Adult↗