In this study we describe a novel sensor system to detect toxic chemicals based on measurement of the quantity of Saccharomyces cerevisiae P450 mRNAs induced by them. Detection was conducted using a flow-injection-type sensor system based on surface plasmon resonance (SPR). The DNA and peptide nucleic acid (PNA) probes containing a complementary sequence to a part of P450 mRNA were immobilized on the sensor chip and the P450 mRNAs hybridized to the probes were quantified. We succeeded in detecting 10 ng/L (10 ppt) of atrazine using both DNA and PNA probes. Using this sensor system, we were able to detect bisphenol A in addition to atrazine. Furthermore, we achieved higher sensitivity by amplifying the target P450 mRNA based on nucleic acid sequence-based amplification (NASBA). This method allows for sensitive, rapid, and easy detection of some toxic chemicals.

Atrazine↗

PubMedDate not supplied

Rearrangement of human T cell receptor beta and gamma chain genes in adult T cell leukemia/lymphoma.

We studied rearrangement of human T cell receptor genes (TCR) of C beta, C gamma, V gamma and J gamma in 34 cases of adult T cell leukemia/lymphoma (ATLL), consisting of 29 cases with monoclonally integrated HTLV-I proviral DNA (ATLL-W) and five without monoclonal integration (ATLL-O), in comparison with 12 cases of other peripheral T cell lymphomas (non-ATLL). All cases of both ATLL and non-ATLL showed some rearrangement of T cell receptor genes (TCRs) of C beta, C gamma, V gamma, or J gamma. Rearrangement of TCR beta was found in 28 of 29 cases of ATLL-W, all cases of ATLL-O, and eight of 12 cases of non-ATLL. Rearrangement of TCR gamma was observed in 21 of 22 cases of ATLL-W, and in all cases of ATLL-O and non-ATLL. In TCR gamma, rearrangement of C gamma was seen in six of 20 cases of ATLL-W, none of three ATLL-O cases and three of six cases of non-ATLL. V gamma rearrangement occurred in 14 of 18 cases of ATLL-W, one of two cases of ATLL-O, and three of six cases of non-ATLL. Rearrangement of J gamma was found in 16 of 22 cases of ATLL-W, two of five ATLL-O cases, and six of seven non-ATLL cases. Rearrangement was more frequent in ATLL-W than in ATLL-O and non-ATLL. The incidence rate of rearrangement of V gamma families of V gamma 1, V gamma 2, and V gamma 3 was nearly the same in each group, except for deletion of V gamma 3, which was often observed in ATLL but was absent in non-ATLL. These results indicate the usefulness of detection of TCR and HTLV-I proviral DNA to differentiate ATLL from other T cell malignancies.

Adult↗

PubMedDate not supplied

Radiographic features in lymphoepithelial cyst of the pancreas.

Two cases of pancreatic lymphoepithelial cyst are presented. Abdominal ultrasonography and endoscopic ultrasonography demonstrated cysts containing keratinized material, indicative of this diagnosis.

Aged↗

PubMedDate not supplied

Renal lesions in a strain of spontaneously diabetic WBN/Kob rats.

In WBN/Kob strain rats, only males spontaneously develop hyperglycemia, glycosuria, hypoinsulinemia and glucose intolerance from about nine months of age. The kidneys of male rats of this strain were histopathologically studied to evaluate the changes which appeared as complications of diabetes mellitus. Thickening of the basement membrane, increase of the mesangial matrix and fibrin-cap lesions were noted in the glomeruli. Armanni-Ebstein degeneration was occasionally found in the tubules. Linear deposition of plasma components such as IgG and albumin in the basement membrane of the glomeruli, tubules and Bowman's capsule characterized the immunohistological pattern. These findings are similar to the findings in diabetic nephropathy in humans. Since the onset of diabetes mellitus in the strain is slow and symptoms are generally mild, insulin administration is usually not necessary for survival. This strain, therefore, appears to be an important animal model for the study of complications of diabetes in humans.

Animals↗

PubMedDate not supplied

Reduction of thyroid hormone levels by methylsulfonyl metabolites of polychlorinated biphenyl congeners in rats.

Male Sprague-Dawley rats received four consecutive intraperitoneal doses of four kinds of methylsulfonyl (MeSO2) metabolites of polychlorinated biphenyl (PCB) congeners: 3-MeSO2-2,2',3',4',5,6-hexachlorobiphenyl (3-MeSO2-CB132); 3-MeSO2-2,2',3',4', 5,5'-hexachlorobiphenyl (3-MeSO2-CB141); 3-MeSO2-2,2',4',5,5',6-hexachlorobiphenyl (3-MeSO2-CB149) and 4-MeSO2-2,2',4',5,5',6-hexachlorobiphenyl (4-MeSO2-CB149). The congeners were major MeSO2-PCBs determined in human milk, liver and adipose tissue, and the aim was to determine their effect on thyroid hormone levels. All four tested MeSO2 metabolites (20 micromol/kg once daily for 4 days) reduced serum total thyroxine levels by 22-44% at a much lower dose than phenobarbital (PB; 431 micromol/kg once daily for 4 days) on days 2, 3, 4 and 7 after the final doses. Total triiodothyronine levels were reduced 37% by treatment with 4-MeSO2-CB149 at day 7. A 30% increase in thyroid weight was produced by 3-MeSO2-CB141 treatment. Total cytochrome P450 content was increased by 3-MeSO2-CB132, 3-MeSO2-CB141 and 3-MeSO2-CB149, but not by 4-MeSO2-CB149. Thus, it is likely that the 3-MeSO2-hexachlorobiphenyls and 4-MeSO2-CB149 could influence the thyroid hormone metabolism by different mechanism(s). The results show that tested 3- and 4-MeSO2 metabolites of PCB congeners reduce thyroid hormone levels much more than PB in rats. Our finding suggests that the metabolites may act as endocrine-disrupters.

Animals↗

PubMedDate not supplied

Usefulness of a narrow-band reflectance spectrophotometer in evaluating effects of depigmenting treatment.

As a depigmenting treatment, combined topical applications of all-trans retinoic acid (atRA) aqueous gel and 5% hydroquinone, 7% lactic acid ointment were used for Oriental patients with hyperpigmented skin lesions such as senile lentigines and nevus spilus. A narrow-band reflectance spectrophotometer and a tristimulus colorimeter were used to evaluate objectively the intensity of pigmentation and erythema at each clinical visit. L*, a*, and b* values measured with a tristimulus colorimeter (Chroma Meter CR-300) enabled the evaluation of erythema but not pigmentation. On the other hand, the melanin and hemoglobin values measured with a narrow-band reflectance spectrophotometer (Mexameter MX-16) expressed both erythema and pigmentation well. It was revealed that, in our bleaching protocol, the narrow-band reflectance spectrophotometer was quite useful for estimating accurately the intensity of pigmentation and erythema and determining the best time point for the cessation of atRA treatment.

Administration, Topical↗

PubMedDate not supplied

Effects of highly toxic organochlorine compounds retained in human body on induction of sister chromatid exchanges in cultured human lymphocytes.

In this study, we investigated the effect of mixture of the organochlorine compounds, which very resembled their contamination of healthy Japanese people in its composition, on the induction of sister chromatid exchanges (SCEs) in human whole-blood cultures in order to clarify their genotoxicity as a whole. The following results were obtained. Regardless of the presence or absence of 7,8-benzoflavone (ANF) in the blood culture system, we could observe a fairly good dose-response relationship between the concentration of the mixture of organochlorine compounds and the induction of SCEs/cell. In particular, we found that 50% effective concentration of the mixture of the organochlorine compounds was considered to be only about 3 times greater level over the average concentration in the healthy people, namely 70ppt as 2,3,7,8-TCDD, in the absence of ANF and about 8 times more than that in the presence of ANF.

Adult↗