Interrelationship of cardiovascular effects, plasma levels of nicorandil, and vascular cGMP formation in conscious rats

The relationship between the dual activity of nicorandil (KATP channel-opening activity and nitrate-like action), plasma levels, and changes in vascular cGMP levels and cardiovascular parameters was investigated in conscious rats. Nicorandil (3 mg kg(-1), p.o.) was rapidly absorbed and caused a significant reduction in blood pressure, lasting for at least 1 h, increases in heart rate and femoral blood flow, and decreases in femoral vascular resistance. These were entirely abolished by intravenous glibenclamide (20 mg kg(-1)). The plasma concentration of nicorandil reached a maximum 30 min after dosing. After administration of nicorandil, a correlation was observed between blood pressure and plasma nicorandil level or femoral vascular resistance. A significant increase (P < 0.05) in the cGMP content of the thoracic aorta occurred 15 min after administration of nicorandil, and persisted for at least 2 h. These results imply that nicorandil induces vasodilatation by opening KATP channels in peripheral resistance vessels, leading to overt reduction of blood pressure, but acts on conductance vessels mainly through nitrate-like activity.

Vascular levels and cGMP-increasing effects of nicorandil administered orally to rats

We examined a relation between cyclic guanosine monophosphate (cGMP) production in thoracic aorta, as an indicator probably reflecting the vascular response, and the vascular as well as plasma levels of nicorandil administered orally to rats. Nicorandil (3 mg/kg) given orally was rapidly absorbed, reaching the maximal plasma (approximately 2,600 ng/ml) and vascular concentrations (approximately 176 ng/g) at 15 min after the dosing and thereafter decreased rapidly. Even 2 h after the dosing, the level of the vascular cGMP formation in vivo remained significantly higher (approximately 1,000 fmol/mg increase from the control level) in the nicorandil-treated group, compared with the vehicle-treated one, and was enough to develop pronounced muscle relaxation in in vitro aortic preparations. However, it seems that the vascular cGMP increase in vivo was not always correlated to the plasma concentration of nicorandil, because the plasma concentration (approximately 750 ng/ml corresponding to 3.5 microM) at 2 h after the dosing, caused only relatively low cGMP production (300-400 fmol/mg increase from the control level), when tested in in vitro aortic preparations. Our study may indicate, therefore, that the vascular cGMP elevation in vivo is due to the content of nicorandil effectively remaining at its vascular targets of action as well as the plasma nicorandil concentration.

Expression of proliferating cell nuclear antigen (PCNA) and apoptosis related antigen (LeY) in epithelial skin tumors

We semiquantitatively analyzed expression of PCNA and LeY in seborrheic keratosis (SK), actinic keratosis (AK), Bowen's disease (BD), and squamous cell carcinoma (SCC), using immunocytochemically stained tissue sections. PCNA expression increased in a stepwise fashion from low levels in normal skin to higher expressions within SK, AK, BD, and SCC. The levels of LeY protein also increased in this order. The PCNA expression pattern shifted from expression limited to the basal and suprabasal cell layers (in normal skin and SK) to expression extending to the upper squamous and granular layers (in AK, BD, and SCC). On the other hand, the pattern of LeY expression shifted from the granular (in normal skin) to the upper squamous (in SK and AK) and suprabasal layers (in BD and SCC). These findings suggest that PCNA expression is related to the degree of cell proliferation and that LeY expression is related to the degree of differentiation or keratinization of tumor cells. In addition, PCNA and LeY show a reciprocal relationship in their expression.

Activation of mitogen-activated protein kinases is not required for the extension of neurites from PC12D cells triggered by nerve growth factor

Numerous studies with PC12 cells have suggested that the mitogen-activated protein (MAP) kinase pathway might play a major role in the neuronal differentiation that is induced by nerve growth factor (NGF). Cells of the PC12D subline extend neurites within several hours in response to NGF in the presence of inhibitors of the synthesis of RNA and protein. We examined the effects of a specific inhibitor 2-(2'-amino-3'-methoxyphenyl)-oxanaphthalen-4-one (PD98059) of the MAP kinase kinase (MEK)/MAP kinase pathway on the NGF-induced outgrowth of neurites in PC12D cells. The increase in MAP kinase activity in response to NGF was reduced by 80% upon treatment of PC12D cells with 50 microM PD98059, whereas the NGF-dependent formation of ruffles and the subsequent outgrowth of neurites were not blocked by PD98059 at this concentration. The outgrowth of neurites from conventional PC12 cells by NGF was suppressed by the addition of 50 microM PD98059 as reported by Pang et al. [L. Pang, T. Sawada, J. Stuart,S.J. Decker, A.R. Saltiel, Inhibition of MAP kinase kinase blocks the differentiation of PC12 cells induced by nerve growth factor, J. Biol. Chem. 270 (1995) 13585-13588]. In contrast, the rapid regeneration of neurites from PC12 cells primed with NGF, was not altered in the presence of the same dose of the inhibitor of MEK. It appeared, therefore, that the activation of the MAP kinase pathway was not necessarily required for the NGF-dependent extension of neurites. When PC12D cells were transfected with the dominant inhibitory Ha-ras Asn-17 gene, the induction of the mutant Ras protein led the suppression of the rapid outgrowth of neurites in response to NGF but not to dibutyryl cyclic AMP (dbcAMP). The result implies a direct involvement of Ras protein in the NGF-induced signal transduction that lead to the formation of neurites in PC12D cells. We can conclude that the activation of MAP kinase and selective gene expression are required for the differentiation of conventional PC12 cells to sympathetic neuron-like cells and that activation of Ras protein and, subsequently, of a MAP kinase-independent pathway might be involved in the extension of neurites from PC12D cells or in the regeneration of neurites from primed PC12 cells in response to NGF.

The guinea-pig skin sensitization test revisited: an evaluation formula to predict possible sensitization levels for eight chemicals used in household products

In predicting human skin sensitization due to possible risky chemicals, it is not sufficient to evaluate solely the minimum induction dose (MID) or the standard challenge dose (SCD) in the Guinea Pig Maximization Test (GPMT). Nakamura et al. (1994) (Nakamura, A., Momma, J., Sekiguchi, H., Noda, T., Yamano, T., Kaniwa, M., Kojima, S., Tsuda, M., Kurokawa, Y., 1994. A new protocol and criteria for quantitative determination of sensitization potencies of chemicals by guinea pig maximization test. Contact Dermatitis 31, 72-85) previously measured the residual dose of chemicals in the products implicated in human allergic accidents, and stated that '... the level of chemical in the products (direct exposure-dose = DED) was similar to or higher than value of sensitization potency.' However, several of the chemicals listed in their article, show an even lower value of sensitization potency than the DED, although a potential correlation between results of the GPMT and the DED was seemed to be evident; a key question about the essential rule of those parameters therefore remains open. Using the data of Nakamura et al. (1994), we analyzed the functional rules of the three independent parameters, the MID, the SCD, and the DED on which the GPMT is based. Calculations of the degree of allergic reactions elicited in humans provided a range of discrimination constants (D) using the formula; D = DED/(MID*SCD). Possible human allergic accidents may be predicted when the dose of a candidate chemical in a chemical product (equal to DED) exceeds the value; D*(MID*SCD), following the correct evaluation of the MID as well as the SCD.

Ultrastructural changes in motor endplates of the lumbrical muscles of rats induced by a microsomal Ca2+ ATPase inhibitor, 2,5-di(tert-butyl)-1,4-hydroquinone

Female Wistar rats were treated orally for 5 days with 80 mg/kg body weight of 2,5-di(tert-butyl)-1,4-hydroquinone (DTBHQ), a microsomal Ca2+ ATPase inhibitor. Motor endplates of the lumbrical muscles were examined by light and electron microscopy. There was a decrease in body weight in the treated rats from the first day after administration, and toxic signs appeared after the third day, such as adoption of a prone position, salivation, lacrymation, and an abnormal gait and/or muscle weakness. No remarkable macroscopic or light microscopic changes were noted in the lumbrical muscles as well as other peripheral nerves of hind legs of the treated rats killed 1 day after the last DTBHQ treatment. Ultrastructurally, neurotoxicity characterized by loss of synaptic vesicles and mitochondria in the motor endplates, and by destruction of the motor terminals was detected in the lumbrical muscles of the treated rats. These results strongly indicate that DTBHQ targets the motor endplates in the rat lumbrical muscles and suggest that the resultant damage is responsible for the appearance of neurological signs, such as an abnormal gait and loss of muscle control.

The PC motif: a novel and evolutionarily conserved sequence involved in interaction between p40phox and p67phox, SH3 domain-containing cytosolic factors of the phagocyte NADPH oxidase

The superoxide-generating NADPH oxidase, dormant in resting phagocytes, is activated during phagocytosis following assembly of the membrane-integrated protein cytochrome b558 and cytosolic factors. Among the latter are the three proteins containing Src homology 3 (SH3) domains, p67phox, p47phox and p40phox. While the first two factors are indispensable for the activity, p40phox is tightly associated with p67phox in resting cells and is suggested to have some modulatory role. Here we describe a systematic analysis of the interaction between p40phox and p67phox using the yeast two-hybrid system and in vitro binding assays with recombinant proteins. Both methods unequivocally showed that the minimum requirements for stable interaction are the C-terminal region of p40phox and the region between the two SH3 domains of p67phox. This interaction is maintained even in the presence of anionic amphiphiles used for the activation of the NADPH oxidase, raising a possibility that it mediates constitutive association of the two factors in both resting and activated cells. The C-terminal region of p40phox responsible for the interaction contains a characteristic stretch of amino acids designated as the PC motif, that also exists in other signal-transducing proteins from yeast to human. Intensive site-directed mutagenesis to the motif in p40phox revealed that it plays a critical role in the binding to p67phox. Thus the PC motif appears to represent a novel module for protein-protein interaction used in a variety of signaling pathways.

Aluminum taken up by transferrin-independent iron uptake affects the iron metabolism in rat cortical cells

We previously demonstrated that cultured human fibroblasts internalize iron via transferrin-independent iron uptake (Tf-IU), redox, and receptor-mediated endocytosis uptake systems [Oshiro, S., Nakajima, H., Markello, T., Krasnewich, D., Bernardini, I., and Gahl, W.A. (1993) J. Biol. Chem. 268, 21586 21591]. Of these iron transport systems, the Tf-IU system is involved in the accumulation of transition metals in various mammalian cells. It is also known that in experimental animals fed aluminum (Al), Al at micromolar level selectively accumulates in the brain. In the present study, we examined the effects of Al accumulated in the brain cells on iron transport by the Tf-IU system and iron metabolism, using primary cultures from fetal rat cerebral cortex. Pretreatment of cells with 200 microM Al-nitrilotriacetate upregulated the Tf-IU system for iron. Moreover, of various metals tested, Al markedly upregulated the Tf-IU activity. To examine the influence of Al on iron metabolism, the interaction between Al accumulated in the cells and iron-responsive element binding protein (IRE-BP), a cellular iron regulator, was examined by Northern blot analysis, and activity assay: Al decreased the Tf receptor mRNA level and increased the aconitase activity of IRE-BP. The increase of aconitase activity by Al was also observed in vitro. These results suggest that Al accumulated in cortical cells affects iron metabolism.

Triple extramammary Paget's disease

BACKGROUND

Triple extramammary Paget's disease (TEPD) has been considered to be rare in the English literature, and its incidence and characteristics are unclear. There are many therapeutic options for treating extramammary Paget's disease (EPD).

OBJECTIVE

Our purpose was to investigate how many TEPD cases have been reported previously and to describe their characteristics. We also describe the effectiveness of radiotherapy for them.

METHODS

We report two TEPD cases, and summarize previously reported TEPD cases together with our cases.

RESULTS

Twenty-three TEPD cases have been reported previously. Of these, 19 cases have been in Japan. All but one patient with TEPD were male. Their axillary lesions often showed no eruptions or very slight erythema. Radiotherapy for our cases was effective although the effectiveness of radiotherapy is controversial.

CONCLUSION

In genital Paget's disease bilateral axillae should be examined histologically, even if they show no or slight eruptions. Radiotherapy may be useful for EPD, particularly axillary Paget's disease.

Perianal Paget's disease years after rectal adenocarcinoma removal

BACKGROUND

Perianal Paget's disease often coincides with anorectal carcinoma, which extends into the epidermis from a contiguous organ.

OBJECTIVE

Our purpose was to present a patient with perianal Paget's disease who had a rectal adenocarcinoma excised 14 years previously in another hospital and to determine whether there is a relationship between the perianal Paget's disease and the rectal adenocarcinoma.

METHODS

We examined the resected specimens of the rectal adenocarcinoma and the perianal Paget's disease histologically.

RESULTS

In the resected specimen of the rectal adenocarcinoma, Paget cells were present within the anal epidermis adjacent to the rectal adenocarcinoma. The Paget cells showed the same histochemical and immunohistological findings as the adenocarcinoma cells.

CONCLUSION

There was a close relationship between the perianal Paget's disease and the rectal adenocarcinoma. It is probable that the Paget cells were derived from direct spread from the rectal adenocarcinoma.

p32 protein, a splicing factor 2-associated protein, is localized in mitochondrial matrix and is functionally important in maintaining oxidative phosphorylation

Human p32, originally cloned as a splicing factor 2-associated protein, has been reported to interact with a variety of molecules including human immunodeficiency virus Tat and complement 1q (C1q). p32 protein is supposed to be in the nucleus and on the plasma membrane for the association with human immunodeficiency virus Tat and C1q, respectively. None of the interactions, however, is proven to have a physiological role. To investigate the physiological function of p32, we determined the intracellular localization of p32. The fractionation of cells, fluorescent immunocytochemistry, and electron microscopic immunostaining show that p32 is exclusively localized in the mitochondrial matrix. We cloned a Saccharomyces cerevisiae homologue of human p32 gene, referred to yeast p30 gene. The yeast p30 protein is also localized in the mitochondrial matrix. The disruption of the p30 gene caused the growth retardation of yeast cells in a glycerol medium but not in a glucose medium, i.e. the impairment of the mitochondrial ATP synthesis. The growth impairment was restored by the introduction of the human p32 cDNA, indicating that p30 is a functional yeast counterpart of human p32. Taken together, both p32 and p30 reside in mitochondrial matrix and play an important role in maintaining mitochondrial oxidative phosphorylation.

Autoantibody reactive with the human general transcription factor TFIIF in sera from patients with autoimmune disorders

Transcription factor (TF) IIF, a heteromeric protein composed of two subunits, RAP30 and RAP74, is required for both specific initiation and elongation of mRNA synthesis by RNA polymerase II. We have identified high titre of specific autoantibodies against the RAP74 subunit of TFIIF in sera from patients with systemic lupus erythematosus (SLE) as well as those with rheumatoid arthritis (RA), periarteritis nodosa (PN), Sjögren's syndrome (SS), dermatomyositis (DM), and mixed connective tissue disease (MCTD) by Western blot or immunoprecipitation. The epitopes recognized by autoantibodies were shown to be preferentially clustered at the central charged region. Anti-RAP74 autoantibody was shown to suppress the activity of TFIIF-stimulated elongation of mRNA synthesis by RNA polymerase II. It is concluded that some patients with autoimmune disorders develop specific autoantibodies against the RAP74 subunit of TFIIF.

Phosphorylation of human general transcription factors TATA-binding protein and transcription factor IIB by DNA-dependent protein kinase--synergistic stimulation of RNA polymerase II basal transcription in vitro

DNA-dependent protein kinase (DNA-PK) has been known to catalyze phosphorylation of a number of regulatory factors involved in DNA replication and transcription such as simian virus 40 T antigen, p53, c-Myc, Sp1, and RNA polymerase II (Pol II). We examined the possibility that DNA-PK phosphorylates the general transcription factors TATA-binding protein (TBP) and transcription factor (TF) IIB, which play key roles in the formation of transcription initiation complex with Pol II. By using a highly purified preparation of DNA-PK from Raji cells, both TBP and TFIIB were shown to be phosphorylated in vitro by DNA-PK. We then investigated the effect of the phosphorylation of these factors on Pol II basal transcription. Stepwise analysis of preinitiation complex formation by electrophoretic mobility shift assay revealed that the phosphorylation of TBP and TFIIB by DNA-PK did not affect the formation of promoter (P)-TBP and P-TBP-TFIIB complexes but synergistically stimulated the formation of P-TBP-TFIIB-TFIIF-Pol II complex. Similarly, combination of the phosphorylated TBP and TFIIB synergistically stimulated Pol II basal transcription from adenovirus major late promoter. These observations suggest that DNA-PK could positively regulate the Pol II basal transcription by phosphorylating TBP and TFIIB.

Telomerase elevation in pancreatic ductal carcinoma compared to nonmalignant pathological states

Telomerase activity was measured in surgically resected tissues of 20 human pancreatic ductal carcinomas, 12 adenomas, 5 pancreatitis tissues, 14 normal pancreatic ducts, and 13 normal pancreatic tissues (primarily made up of acinar cells) using a PCR-based telomerase assay. Relative telomerase activity was expressed as the equivalent telomerase intensity of the number of cells of a human pancreatic cancer cell line, MIA PaCa-2, per microgram of protein in the tissue samples. The median value (25th percentile, 75th percentile) of relative telomerase activity in pancreatic carcinomas was 13.2 (3.58, 244), which was significantly higher relative to normal tissues, normal ducts, pancreatitis tissues, and adenomas (P < 0.0001). When the cutoff value of relative telomerase activity was set at 1.00 and 3.00, the positivity rates of telomerase activity in pancreatic ductal carcinomas were 100 and 80%, respectively. Some of the adenoma samples displayed a weak telomerase ladder. However, when semiquantitatively analyzed, the relative telomerase activity of all adenoma tissues was less than 1.00 equivalent cells per microgram protein of the tissues, which was equivalent to the values encountered in normal ducts. Thus, our results indicate that reactivation of telomerase may occur at a late stage of pancreatic ductal carcinogenesis. Therefore, telomerase may be a specific marker for distinguishing pancreatic cancer from pancreatitis and adenomas.

Characterization of the human thrombopoietin gene promoter. A possible role of an Ets transcription factor, E4TF1/GABP

Thrombopoietin (TPO), the ligand for c-Mpl, is a cytokine that regulates megakaryocyte growth and development. We have cloned the 5'-flanking region of the human TPO gene and analyzed its promoter activity. The human TPO gene promoter lacks a TATA box and directs transcription initiation at multiple sites over a 50-nucleotide region. Transient expression in a human liver cell line (PLC) of promoter fragment-luciferase reporter gene constructs containing a series of 5'-truncated sequences or site-directed mutations identified a sequence 5'-ACTTCCG-3' from -69 to -63 as a positive cis-acting element for high level expression of TPO gene. This sequence contains a core motif (C/A)GGA(A/T) for Ets family proteins in the noncoding strand. Gel mobility shift assays performed with nuclear protein from PLC cells identified a DNA binding protein(s) specific for the element. Anti-E4TF1-60(GABPalpha) or anti-E4TF1-53/47(GABPbeta) antibodies supershifted the complex in gel shift assay. Furthermore, co-expression of E4TF1-60 and E4TF1-53/47 squelched TPO gene expression in PLC and HepG2 cells. It is concluded that Ets family transcription factor E4TF1(GABPalpha/beta), an ubiquitously expressed protein, is required for high level expression of the TPO gene in liver.

Inhibition of the nerve growth factor-induced outgrowth of neurites by trichostatin A requires protein synthesis de novo in PC12D cells

Trichostatin A (TSA) inhibits the activity of histone deacetylase and blocks both oncogenic ras-induced and nerve growth factor-induced (NGF-induced) outgrowth of neurites from PC12 cells. Cells of the PC12D subline extend neurites very rapidly in response to NGF, basic fibroblast growth factor (bFGF), dibutyryl cAMP (dbcAMP) and to staurosporine, even in the presence of an inhibitor of RNA synthesis, as do primed PC12 cells or cultured sympathetic neurons. TSA at 100 nM selectively blocked the NGF- and bFGF-induced outgrowth of neurites from PC12D cells, but not the outgrowth induced by dbcAMP or staurosporine. The NGF-induced changes in morphology with the relocalization of F-actin, were not inhibited by TSA. However, the subsequent formation of growth cones and the outgrowth of neurites was blocked. The activation of mitogen-activated protein (MAP) kinases in NGF-stimulated cells was also unaffected by TSA. When TSA was added to cells that were extending neurites in response to NGF, the number of neurite-bearing cells decreased after a lag period. In the presence of inhibitors of RNA or protein synthesis namely, actinomycin D, cordycepin, and cycloheximide, TSA no longer blocked the NGF- and bFGF-dependent outgrowth of neurites from PC12D cells. Regardless of the effect of TSA, the rapid outgrowth of neurites from PC12D cells was unaffected by the presence of cycloheximide, which inhibited protein synthesis by 97%, as determined by monitoring the incorporation of [35S]methionine/cysteine. This study provides proof that the NGF-induced elongation of neurites does not require protein synthesis de novo. These observations suggest that TSA might not inhibit the early signal-transduction pathway of NGF, but might block the late pathway, which is related to the formation of growth cones and/or neurites. Cellular conditions that no longer allow the NGF- and bFGF-mediated elongation of neurites might be produced by TSA via synthesis of some specific protein(s) due to changes in RNA(s) synthesis de novo.

Semi-quantitative analysis of telomerase in pancreatic ductal adenocarcinoma

Using a polymerase chain reaction-based amplification assay, we measured telomerase activity in surgically resected pancreatic ductal carcinomas (n = 16 cases) and normal ducts (n = 6), comparing findings with the telomerase activity of a human pancreatic cancer cell line, MIA PaCa-2, as a standard, i.e., relative telomerase activity was determined. Telomerase activity was expressed as the equivalent telomerase intensity of the number of cells of MIA PaCa-2 per microgram protein of tissue samples. The median value for telomerase activity in normal pancreatic ducts was 0.13 and the 25th and 75th percentile were 0.01 and 0.76. The median value for telomerase activity in pancreatic ductal adenocarcinoma was 34.7 (25th percentile, 4.98; and 75th percentile, 296), significantly higher than that of normal ducts (P < 0.001). When the cut-off value was set at 1.0 and 3.0, the telomerase positivity rate of pancreatic ductal adenocarcinomas was 100% and 81.3%, respectively. Telomerase may be specific marker for pancreatic ductal carcinomas.

Evans' syndrome associated with Graves' disease

A 36-year-old woman who had had Graves' disease for 6 years was admitted with severe thrombocytopenia. Evans' syndrome was diagnosed. The patient's family history showed multiple cases of Graves' disease but no cases of Evans' syndrome. Both conditions in this patient improved with corticosteroid and thiamazole therapy. Several autoimmune antibodies were found, but a common autoimmune mechanism was not clearly shown. Although the combination of Graves' disease and Evans' syndrome had not occurred previously in her family, genetic factors may play an important role in the pathogenesis of both conditions.

[Specific inhibitory effect of hybrid liposomes on the growth of hybridoma cells in vitro]

Remarkably high inhibitory effects of the hybrid liposomes composed of L-alpha-dimyristoyl-phosphatidylcholine (DMPC) and polyoxyethylenealkyl ether (C14(EO)n, n = 6-8 and C12(EO)n, n = 8-12)) on the growth of human lymphoma-human B-lymphocyte hybridoma (HF) cells in vitro were obtained. The hybrid liposomes composed of 90 mol% DMPC/10 mol% C14(EO)n (n = 6-8) or C12(EO)n (n = 8-12) were more fluid as compared with 90 mol% DMPC/10 mol% C14(EO)4 or C12(EO)n (n = 4, 23) hybrid liposomes on the basis of fluorescence polarization measurements. These results suggest that the inhibitory effects of the hybrid liposomes on the growth of HF cells should be related to the membrane fluidity. No toxicity to normal rats in vivo was observed in the experiment using 90 mol% DMPC/10 mol% C14(EO)7 or 90 mol% DMPC/10 mol% C12(EO)12 hybrid liposomes.

Analysis of shape and retractability of the prepuce in 603 Japanese boys

PURPOSE

We evaluated preputial development in Japanese boys.

MATERIALS AND METHODS

Preputial retractability and formation of a tight ring were evaluated in 603 Japanese boys 0 to 15 years old.

RESULTS

The incidence of a completely retractable prepuce gradually increased from 0% at age 6 months to 62.9% by 11 to 15 years, while that of a tight ring decreased with age from 84.3 to 8.6%. Nine boys had balanoposthitis but none had a symptomatic urinary tract infection.

CONCLUSIONS

Incomplete separation of the prepuce is common and normal in neonates and infants, and preputial separation progresses until adolescence. Awareness of these findings will eliminate unnecessary circumcision in boys.

[A 52-week oral toxicity study of a new antineoplastic agent S-1 in dogs]

52-week oral repeated-dose S-1 toxicity studies were conducted. Male and female dogs were orally treated with 0, 0.1, 0.5 or 2.5 mg/kg/day for 52 weeks and permitted to recover for 13 weeks. Furthermore, to estimate the no-toxic dose, male and female dogs were given S-1 orally for 52 weeks at doses of 0, 0.004 and 0.02 mg/kg/day. The 2.5 mg/kg/day regimen produced one dead or moribund dog of each sex; black-brown patch (melanin deposition) and inflammatory changes in the eyes and skin; decreased in body weight gains; increases in MCV, MCH, monocyte ratio, and serum protein and uric acid; decreases in lymphocyte ratio and erythrocyte count, hematocrit, hemoglobin, albumin, A/G ratio, cholesterol (esterified, total and free), phospholipids, triglycerides, cholinesterase activity and creatinine; increases in relative liver and adrenal weights. Histopathological examinations revealed melanin deposits in superficial lymph nodes, increases in macrophage and plasma cell accumulation, and corneal atrophy accompanied by melanin deposits and capillary proliferation. A slight black-brown patch (melanin deposition) in the conjunctiva and skin was observed in the 0.1 and 0.5 mg/kg/day groups. No drug-related changes were observed in groups that received 0.02 and 0.004 mg/kg/day. All changes observed during the treatment period disappeared during recovery except for melanin deposits in the conjunctiva and superficial lymph nodes, corneal opacity, and a few hematological and blood chemistry parameters. In conclusion, the no-toxic dose in these 52-week studies was estimated to be 0.02 mg/kg/day.

Analysis of shape and retractability of the prepuce in 603 Japanese boys

PURPOSE

We evaluated preputial development in Japanese boys.

MATERIALS AND METHODS

Preputial retractability and formation of a tight ring were evaluated in 603 Japanese boys 0 to 15 years old.

RESULTS

The incidence of a completely retractable prepuce gradually increased from 0% at age 6 months to 62.9% by 11 to 15 years, while that of a tight ring decreased with age from 84.3 to 8.6%. Nine boys had balanoposthitis but none had a symptomatic urinary tract infection.

CONCLUSIONS

Incomplete separation of the prepuce is common and normal in neonates and infants, and preputial separation progresses until adolescence. Awareness of these findings will eliminate unnecessary circumcision in boys.

Quantitative analyses of lesion areas of coronary atherosclerosis in cholesterol-fed rabbits

A simple method to quantitatively evaluate atherosclerosis in the rabbit coronary arteries by measuring macroscopic lesion areas (%) was attempted in the present study. Sixteen rabbits were fed a 0.5% cholesterol diet for 15 weeks and then 9 rabbits were sacrificed whereas the remaining 7 rabbits were maintained for further 9 weeks on a normal chow (at week 24). The left circumflex coronary arteries (LCX) were excised from the rabbit hearts under stereoscopic observation. The prepared arterial strips of LCX were 38.7 +/- 7.1 mm long and all of them reached the cardiac apex from the orifice. At week 15, the lesion area in LCX was negligible (3.2 +/- 0.4%) whereas the aortic lesions significantly developed (50.0 +/- 7.6%). At week 24, atherosclerotic lesions in both LCX and aortas increased to 32.8 +/- 9.2% and 85.9 +/- 5.6%, respectively. This is the first report that determined the luminal surface areas of atherosclerotic lesions in rabbit coronary arteries. This method may be more practical and useful for quantitative evaluation of coronary atherosclerosis in a large number of rabbits than histological observations of serial sections of rabbit hearts.