Search

We evaluated impedance pharyngography (IPG), a new method to assess swallowing function based on changes in the electrical impedance of the neck during swallowing. The electrical impedance of the neck, recorded by the 4-electrode method, changed with the equivalent cross-sectional area of the route of the electric current due to reflex activities of related organs during swallowing. IPG waveforms accurately recorded the swallowing process, therefore. We recommend IPG for assessing swallowing function because we expect IPG to provide the following advantages over conventional diagnostic techniques: it is a quantitative method that allows for the objective assessment of swallowing function; it is a simple procedure that is convenient for the patient and could be used for screening; it is inexpensive and non-invasive, so could be performed repeatedly in situations such as rehabilitation; and it uses highly portable equipment suitable for community use.

To investigate the damage mediated by anti-cancer drugs in normal cells, we examined the effect of such drugs on apoptosis of normal cells of the small intestinal epithelium and the bone marrow by in situDNA end-labelling and transmission electron microscopy. Mice received a single dose of 5-fluorouracil (5-FU) or cisplatin, or repeated daily doses of 5-FU for 7 days. In mice treated with a single dose of 5-FU 50 mg/kg or cisplatin 5 mg/kg, the number of apoptotic cells appearing in the small intestine 12 h after injection was relatively small, but increased steadily reaching a peak after 36 h and then decreasing to close to that in the control group by 48 h. In bone marrow cells, results were similar in mice treated with single doses of 5-FU 50 mg/kg but apoptosis increased much less in those treated with cisplatin 5 mg/kg. The proportion of apoptotic cells reached peak values earlier at higher concentrations of 5-FU or cisplatin both in small intestine and in bone marrow. In the mice treated repeatedly with 5-FU 50 mg/kg, the proportion of apoptotic small intestinal epithelial cells reached a succession of peaks at 48-h intervals. Mice treated repeatedly with 5-FU 50 mg/kg also showed a rapid increase in diarrhoea symptoms and a steady decrease in the height of villi. Our results suggest it may be possible to prevent the side-effects of anti-cancer drugs by inhibiting apoptosis in the gastrointestinal tract.

Not Available

Measurement of the kinematic movement of burden materials is important for the stable and efficient operation of the blast furnaces. Without devising several types of burden sensor, few of them are put to practical use because of limitation of the proposed principles which are insufficient for measuring burden materials having complexity of chemical and physical change during the deoxidation process in furnaces and bad surroundings in addition. A microwave sensor is newly developed, which is able to use at almost every part in a furnace. This sensor can get simultaneously signals relating to the descent velocity, the thickness of ore and coke layer and the particle size of burden by use of the reflecting and scattering X-band wave. Experimental results at laboratory showed that these variables can be measured by the microwave burden sensor within the accuracy of ± 10%.

Not Available

X-ray diffraction experiments for stage-2 potassium-intercalated graphite C24K and stage-1 C8K have been carried out. Disordered profiles have been observed for both samples. The measured structure factor S(Q) for the disordered potassium in C8K shows a characteristic subpeak in the small angle region below the first peak, which suggests that there exists a short-range order in the potassium layers. The phases of the pair distribution function g(r) and S(Q) for the potassium layers in C8K disagree with those in C24K. To check the influence of the carbon layers, the profiles of g(r)s of C8K and C24K are compared with that of normal liquid potassium.

We describe here the simultaneous determination of fenitrothion and its metabolite, 3-methyl-4-nitrophenol (MNP), in biological fluids by HPLC after SepPakC18 cartridge extraction and its application to a human poisoning case. One ml of serum or urine mixed with an equal volume of 0.1 N HCl was applied to the SepPakC18 cartridge, which was preactivated using methanol (5 ml), hexane/isopropanol (9/1 v/v, 10 ml), methanol (5 ml) and distilled water (5 ml). After washing by 0.1N HCl(5 ml), the eluate with 5 ml of hexane/isopropanol (9/1 v/v) was concentrated, and the residue was dissolved in 100 μl of methanol containing methaqualone (internal standard, 30 μg/ml). A 20 μ of the aliquot was injected into the HPLC. Recovery yields of fenitrothion and MNP from serum and urine ranged from 78.5-93.3%. Linear calibration curves for fenitrothion and MNP were in the range 0.1 - 10 μg/ml. In a human poisoning case at 18.5 hrs after ingestion of Sumithion, concentrations of fenitrothion and MNP in serum were 11.8 and 3.9 μg/ml and those in urine were less than 0.01 μg/ml and 2.8 μg/ml, respectively.

The role of xanthine oxidase in thyroid function was studied in the rat in vivoby different approaches. Allopurinol, an inhibitor of xanthine oxidase, was administered by mixing it with a powdered diet (16 mg/100 g body wt per day for 10 days). This treatment significantly reduced the total uptake of iodide and inhibited the organification of iodide in the rat thyroid gland. Thyroid xanthine oxidase and dehydrogenase were almost completely inactivated by tungstate, which was given to rats (100 p.p.m./animal per day in drinking water for 10 days) maintained on a purified diet containing low levels of molybdenum. Under these conditions, no inhibitory effect was observed on synthesis of thyroid hormones. It therefore seemed reasonable to assume that the suppressive effect of allopurinol on the biosynthesis of thyroid hormones is not mediated by xanthine oxidase.

1. The metabolic fate of 3,5-diiodo-4-(4'-acetoxy-3'-[125I]iodophenoxy)-benzoic acid was studied in rats and its principal metabolites identified.2. The drug, orally administered, was rapidly and almost quantitatively absorbed from the intestine, and was distributed to liver and kidney. Blood levels of radioactivity reached a plateau 3 to 5 h after administration, and gradually decreased. Radioactivity was rapidly excreted, largely in the bile, and entered into entero-hepatic circulation. Subsequent excretion in faeces and urine, amounted to 60 and 25%, respectively, within 72 h.3. Repeated oral administration of the drug did not show any accumulation, except in the thyroid gland, which showed a concentration five times higher than that after a single administration.4. The metabolic fate of the drug in animals receiving a subtoxic dose of the unlabelled drug for 4 weeks did not significantly differ from that in control animals.5. The faecal metabolite was identified as the deacetylated drug. Glucuronide and sulphate conjugates of the deacetylated drug accounted for 48 and 30%, respectively, of the biliary metabolites. The urinary metabolite was largely iodide (80%).6. These results indicate that the drug is eliminated by two distinct pathways of metabolism, the major one is the biliary route following deacetylation and conjugation, and the minor one is the urinary route after de-iodination.

The non-Kolbe reaction of N-benzoyloxazolidine derivatives 6 derived from l-serine gave optically active N,O-acetals 7 when graphite was used as an anode material. This reaction represents the first example of “memory of chirality” in carbenium ion chemistry. The material used for the anode was critical for the memory of chirality. The substitution of carboxyl group with methoxyl group was found to proceed with an inversion mechanism.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.