Reproductive and developmental toxicity studies of toluene. I. Teratogenicity study of inhalation exposure in pregnant rats

Toluene is a widely used solvent in industry which is the subject of abuse among the younger generation. A teratogenicity study of toluene by inhalation exposure was carried out in Sprague-Dawley rats and the effects on dams, fetuses and offspring were assessed. Pregnant females were exposed to 600 or 2000 ppm toluene for 6 h/day from day 7 to day 17 of pregnancy. The control group inhaled conditioned clean air under the same exposure conditions. Maternal exposure to 2000 ppm toluene caused significant toxic effects such as body weight suppression of dams and offspring, high fetal mortality and embryonic growth retardation, but no external, internal or skeletal anomalies were observed in the fetuses of any treated group. In addition, there were no differences in the results of pre- and postweaning behavioral tests of the offspring. However, no toxic or teratogenic changes which could be related to toluene exposure were apparent in the 600 ppm group. Further studies are warranted with toluene at higher concentrations applied during the period of organogenesis.

[A case of pulmonary eosinophilic granuloma and diabetes insipidus]

A 31-year-old man was admitted to our hospital because of a sudden onset of thirst, polyposia, and polyuria. Five years previously he had been admitted to our hospital because of a dry cough. On the first admission, the chest X-ray film had shown reticular shadows and bullous changes in both upper lung fields. Histological examination of a transbronchial lung biopsy specimen had revealed that the nodular lesion in the interstitium of the alveolar lesion consisted of an aggregate of many Langerhans cells with pale cytoplasm and partly convoluted nuclei. In addition, immunoperoxidase stain for S-100 protein had been strongly positive in numerous Langerhans cells in a bone biopsy specimen from a left mandibullar lesion, which is the same histological appearance as the lung lesion. A diagnosis of pulmonary eosinophilic granuloma had been made. The course after discharge was not progressive without treatment for 5 years, but the patient suddenly began to have thirst, polyposia, and polyuria. Dehydration, vasopressin tests, and the findings of MRI indicated diabetes insipidus due to a pathological change in the pituitary gland. Although diabetes insipidus is known to be a common complication of pulmonary eosinophilic granuloma, only 9 cases have been reported in Japan.

Occult intrasacral meningocele with tethered cord--case report

A 32-year-old female presented with a history of intermittent, severe lower back pain, exacerbated by pregnancy and persisting for several years. Magnetic resonance (MR) imaging showed a sacral mass as a low signal intensity area on the T1-weighted image and a high signal intensity area on the T2-weighted image, consistent with a cystic structure containing cerebrospinal fluid. A tethered cord attached to the thecal sac was also confirmed. Sacral laminectomy revealed thinned sacral vertebral laminae, but no neuronal elements existed within the cyst. The cyst was attached to the distal thecal sac by a small fistula. The thecal sac was explored, revealing a thick filum terminale, which was transected. The severe pain resolved postoperatively. This type of meningeal cyst, often called "occult intrasacral meningocele," is best diagnosed by MR imaging. Surgery to obliterate the fistulous tract is the optimum treatment. Total removal of the cyst is unnecessary, but evaluation of other associated congenial abnormalities is important.

Electrophysiologic determinants of ventricular rate in human atrial fibrillation

INTRODUCTION

The mechanisms of the ventricular response during atrial fibrillation (AF) remain uncertain. The parameters obtained during an electrophysiologic study, including atrial rates during AF, were analyzed to clarify further the determinants of the ventricular rate during AF.

METHODS AND RESULTS

Thirty patients without manifest preexcitation in whom AF was induced during electrophysiologic study were divided into two groups. Group 1 consisted of 20 patients (ages 55 +/- 10 years) without a dual AV nodal pathway. Group 2 consisted of 10 patients (ages 53 +/- 13 years) having a dual AV nodal pathway. The correlation coefficient between the mean RR interval during AF (mRR) and the mean intra-atrial potential interval during AF (mff) was positive (0.05 [P < 0.05] in group 1 and 0.37 [P = NS] in group 2). The correlation coefficient of the mRR against the functional refractory periods of the AV node (AVFRP) was 0.73 (P < 0.001) in group 1. The correlation coefficients between mRR and the fast AV nodal pathway functional refractory periods and the slow AV nodal pathway effective refractory periods (SPERP) were 0.58 (P = NS) and 0.7 (P < 0.05) in group 2, respectively. The correlation coefficients between mRR against (mff x AVFRP)1/2 in group 1 and (mff x SPERP)1/2 in group 2 were 0.8 (P < 0.001) and 0.72 (P < 0.05), respectively.

CONCLUSIONS

This clinical study did not indicate an inverse relation between the atrial and ventricular rates that had been reported by the previous experimental study. The ventricular rate during AF appeared to be quantitatively related to the atrial rate via AV node function. The importance of the slow pathway in determining the ventricular rate during AF was observed.

[Intensive and high-dose chemotherapy with peripheral blood stem cell transfusion for pediatric malignant brain tumor]

In this study, the newly developed marrow-rescue therapy during myelosuppression is utilized. In this therapy, peripheral blood stem cell transfusion (PBSCT) is administered following high-dose chemotherapy. Harvest of peripheral blood stem cells (PBSC) during myelosuppression following marrow-ablative chemotherapy is a safe, reliable procedure in children with leukemia. And administration of these cryopreserved PBSC is useful in reducing myelosuppression following intensive/ultra high-dose chemotherapy. In this study, several courses of intensive chemotherapy (1 course: VP-16 300mg/m2 x 5 days + carboplatin 400-500mg/m2 x 3 days) and one course of ultra-high dose chemotherapy (1 course: VP-16 400mg/m2 x 8 days + carboplatin 800mg/m2 x 5 days + MCNU 250, 200mg/m2 x each day) with PBSC transfusion were applied in four cases of pediatric malignant brain tumors (2 cases of medulloblastoma, one case of pineoblastoma and anaplastic ependymoma) after surgical reduction. With PBSC transfusion, myelosuppression following high-dose chemotherapy could be overcome without serious complication in all cases. Three cases showed complete remission and one showed partial remission after the operation and intensive chemotherapy. However, CSF dissemination appeared in two cases and they died 20 and 28 months after the onset respectively. Intensive/ultra high-dose chemotherapy with PBSC transfusion is a safe procedure in children with malignant brain tumors. This procedure may enable the postponement of radiation for pediatric malignant brain tumor cases under three years of age.

Hamster to rat kidney xenotransplantation. Effects of FK 506, cyclophosphamide, organ perfusion, and complement inhibition

Hamster to rat renal xenotransplantation was performed with recipient nephrectomies. Recipients were treated beginning on day 0 with continuous FK 506 monotherapy, a 7-day or open-ended monotherapeutic course of cyclophosphamide (CP), and the two drug regimens combined. CP alone (10 mg/kg/day) prevented a xenospecific antibody response and tripled median survival of the kidney (defined as recipient death) from 6 (control) to 18.5 days whereas FK 506 alone had no effect. The drugs in combination were no better than CP alone (15 days) unless the 5-day course of CP was given at a higher dose (15 mg/kg) and started 3 days preoperatively (79 days). In further experiments, adjuvant measures were added to the minimally effective FK 506/7-day CP regimen which gave a median survival of only 15 days. In the most successful modification, intraoperative antibody depletion by the temporary transplantation of third party hamster liver or en bloc kidneys increased median survival from 15 to 34 and 48 days, respectively. An intraoperative i.v. dose administration of the anticomplement drug K76 instead of antibody depletion increased survival to 26 days. Although the events of kidney rejection were similar to those of heart xenografts and partially forestalled by the antibody inhibiting CP treatment, or by antibody depletion, survival for > 100 days was accomplished in only 5 of 86 treated animals. The poorer survival previously reported with cardiac xenotransplantation is largely explained by the life support requirement of the kidneys. Renal failure was responsible for almost all deaths before 60 days, and subnormal renal failure was a pervasive adverse factor thereafter, frequently caused by pyelonephritis which is suspected to have had an immunologic etiology.

Human androgen-induced growth factor in prostate and breast cancer cells: its molecular cloning and growth properties

Androgen-induced growth factor (AIGF) has hormone-regulated properties in the mouse Shionogi carcinoma cell line. To investigate whether or not it is involved in growth of human hormone-responsive cancers, we isolated the human AIGF gene from a placental genomic library. Genomic analyses suggested that the AIGF gene was about 6.5 kilobases in length containing five exons. The deduced amino acid sequence of human AIGF was completely identical with that of the mouse. RT-PCR analyses showed that prostate and breast cancer cell lines, LNCaP, PC-3, and MCF-7, slightly expressed the AIGF gene. Recombinant AIGF enhanced the growth of the human prostate cancer LNCaP cells, and it also markedly stimulated the growth of fibroblasts. These in vitro findings suggest that AIGF might be a possible autocrine or paracrine factor in hormone-responsive cancers.

Stimulation of DNA transcription by the replication factor from the adenovirus genome in a chromatin-like structure

Adenovirus (Ad) genome DNA is complexed with viral core proteins in the virus particle and in host cells during the early stages of infection. This DNA protein complex, called Ad core, is thought to be the template for transcription and DNA replication in infected cells. The Ad core functioned as template for DNA replication in the cell-free system consisting of viral replication proteins, uninfected HeLa nuclear extracts, and a novel factor, template activating factor-I (TAF-I) that we have isolated from uninfected HeLa cytoplasmic fractions. The Ad core did not function as an efficient template in the cell-free transcription system with nuclear extracts of uninfected HeLa cells. The addition of TAF-I resulted in the stimulation of transcription from E1A and ML promoters on the Ad core. TAF-I was required, at least, for the formation of preinitiation complexes. These observations suggest that, in addition to factors essential for transcription on naked DNA template, the factor such as TAF-I needed for replication of the Ad core is also required for transcription from the Ad genome in a chromatin-like structure.

Structure determination of galacto-oligosaccharides by pyridylamination and NMR spectroscopy

Galacto-oligosaccharides formed from lactose by the action of some beta-galactosidases were subjected to gel chromatography on Bio-Gel P-2, and the resulting oligosaccharide fractions were converted into pyridylamino (PA) derivatives. Each PA-oligosaccharide fraction, which consisted of several isomers in a given size-class, was then subjected to HPLC on an ODS column. Twenty-one individual galacto-oligosaccharide components were isolated in this way. The structures of most of these compounds, namely six disaccharides, five trisaccharides, two tetrasaccharides, and a pentasaccharide, were determined by 13C-NMR spectroscopy. The results obtained will be useful for the study of the activity of various galacto-oligosaccharides on the growth of Bifidobacterium species.

Expression of brain-derived neurotrophic factor and p145TrkB affects survival, differentiation, and invasiveness of human neuroblastoma cells

A large number of poor prognosis neuroblastoma (NB) tumors constitutively express brain-derived neurotrophic factor (BDNF) and variably express the gene for its tyrosine kinase (Trk) receptor TrkB. Good prognosis NB tumors typically express high levels of TrkA mRNA, which encodes the signal transducing receptor for nerve growth factor, p140TrkA. These neurotrophins are necessary for neural cell survival and differentiation. This study evaluates the effects of activation of the BDNF-TrkB signal transduction pathway on the growth, survival, morphology, and invasive capacity of NB cells. We find that the addition of BDNF to SY5Y cells induced to express p145TrkB by retinoic acid treatment does not significantly affect cell proliferation yet will support cell survival. Activation of the BDNF-TrkB signal transduction pathway stimulates disaggregation of cells and extension of neuritic processes which can be blocked by a BDNF-neutralizing antibody. Treatment of cells with K252a, an inhibitor of Trk, reverses the cellular disaggregation. An evaluation of the effects of BDNF and nerve growth factor on the ability of NB cells to penetrate basement membrane proteins indicated that BDNF stimulated a 2-fold increase while nerve growth factor inhibited RA-SY5Y cell invasion. Thus, activation of the p145TrkB signal transduction pathway stimulates NB cell survival, disaggregation, and invasion; all characteristics of metastatic cells. Furthermore, these studies indicate that activation of different Trk signal transduction pathways in NB cells results in distinct differences in tumor cell biology and these may be relevant to the clinical course of the patients.

Abundant expression of GLUT1 and GLUT3 in rat embryo during the early organogenesis period

The developmental change of both GLUT1 and GLUT3 protein in rat embryonal and fetal brain was examined using Western blot analysis and immunohistochemistry. The brains were collected from fetuses (gestational days 10 to 20), newborn, and adult rats. On day 10, the levels of GLUT1 and GLUT3 expressions were twofold higher than those of adult levels, but thereafter decreased rapidly as the gestation progressed. The tissue distribution of GLUT1 and GLUT3 in embryo was apparently distinct. On day 10, GLUT1 was expressed in the neural tube, gut, heart and optic vesicle, while GLUT3 was expressed in the surface ectoderm and gut. Thus, high affinity glucose transporters may be required in the early organogenesis period because their energy requirement is completely dependent upon anaerobic glycolysis. GLUT3 may facilitate glucose transfer from amniotic fluid to the embryo and GLUT1 may supply glucose for use as an embryonal fuel.

[Newly developed detection system for serum Helicobacter pylori antibodies using ELISA and its clinical significance]

Using ELISA, a specific and sensitive system that detects serum immunoglobulin G antibodies against all soluble antigens of Helicobacter pylori (Hp) has been developed. This system is used at three different concentrations of Hp antigens coated on the solid phase of the ELISA. Anti-Hp antibodies were judged positive when the difference in the ELISA values between high and middle or middle and low concentrations of antigen were over the specific values. For the ELISA system, called the three point antigen method, sensitivity and specificity of urease activity were 86.9% and 70.8%, respectively. Positive rate for antibodies to serum Helicobacter pylori in dyspeptic patients was higher than that in healthy subjects.

Tissue and serum pepsinogen I and II in gastric cancer identified using immunohistochemistry and rapid ELISA

AIMS

To investigate the immunohistochemical expression and the serum concentrations of pepsinogen I and II in different histological types of gastric cancer as compared with other gastric disorders.

METHODS

Formalin fixed, paraffin wax embedded tissue specimens of 38 gastric cancers obtained from surgical cases were used for the immunohistochemical studies performed with the avidin-biotin complex method using monoclonal antibodies against purified pepsinogen I and II. Pepsinogen concentrations from serum obtained from the above patients, from patients with various other gastric disorders, and from normal controls were measured with a rapid non-radioactive one step enzyme linked immunosorbent assay (ELISA).

RESULTS

Eight of 38 (21%) and seven of 38 (18%) gastric carcinomas showed immunoreactivity to pepsinogen I and pepsinogen II, respectively, without any correlation to histological classification or differentiation. Decreased pepsinogen I concentrations and low pepsinogen I:II ratios were found specifically in cases of gastric carcinoma and polyp, in good accordance with the immunohistochemical results.

CONCLUSIONS

Low serum pepsinogen I concentrations and a low pepsinogen I:II ratio are predictive of gastric neoplasia, correlating with low tissue immunoreactivity to monoclonal antibodies raised against pepsinogen I and II. For mass screening of gastric disease including carcinoma, ELISA using a one step immunoassay performed in the present study is a rapid and reliable non-radioactive method of detecting serum pepsinogen. In addition, immunohistochemical studies showed that pepsinogen production may be increased or diminished as a result of tumour histogenesis, depending on the area of origin and the processes of cell transformation and dedifferentiation.

Antiantiidiotypic response and clinical course of the disease in patients with malignant melanoma immunized with mouse antiidiotypic monoclonal antibody MK2-23

An active specific immunotherapy trial has been implemented in patients with malignant melanoma utilizing the mouse anti-id MAb MK2-23. The latter bears the internal image of the determinant by the anti-HMW-MAA MAb 763.74. The immunogenicity of anti-id MAb MK2-23 is enhanced by conjugation to a carrier and administration with an adjuvant. Anti-id MAb MK2-23 induced humoral anti-HMW-MAA immunity in about 60% of the immunized patients. The latter was associated with a statistically significant survival prolongation. It is suggested that anti-HMW-MAA immunity may have a beneficial effect on the clinical course of the disease by inhibiting the function of HMW-MAA in the biology of melanoma cells.

T1 measurements with clinical MR units

To improve accuracy and feasibility of the proton spin-lattice relaxation time (T1) measurements in routine Magnetic Resonance Imaging (MRI), a phantom with polyvinyl alcohol gels and gadrinium diethylene triamine pentaacetic acid solutions was imaged with 1.5T clinical MR units and T1s were calculated by fitting several models to the observed signal intensities. When an inversion-recovery sequence was applied, we were able to measure T1 with a high degree of precision by taking into account the imperfection of the inversion pulse. With a Turbo-fast low angle shot sequence, we were able to obtain T1 in a short time, but low signal-to-noise ratio limited the precision. Signal intensity with SE sequence was susceptible to variation with the effective flip angle of 90 degrees RF pulse and not suited for T1 measurement.

[The characteristic feature of myocardial imaging with 123I-labeled 15-(p-iodophenyl)-3R,S-methylpentadecanoic acid in hypertrophic cardiomyopathy with asymmetric septal hypertrophy]

The aim of this study was to elucidate the characteristic feature of myocardial imaging with 123I-labeled 15-(p-iodophenyl)-3R,S-methylpentadecanoic acid (BMIPP) in the patients with hypertrophic cardiomyopathy (HCM). In 26 patients with asymmetric septal hypertrophy (ASH), the imaging data were acquired for 15 minutes after the injection of 123I-BMIPP by the emission computed tomography (ECT). ECT image was divided into 17 segments to score the severity of the defect in each segment using a 5-point grading system from score 3 to score -1; score 3 = severely decreased tracer uptake, score 2 = moderately decreased tracer uptake, score 1 = mildly decreased tracer uptake, score 0 = normal and score -1 = increased tracer uptake. Reduced uptake (Defect Score > or = 2) was frequently observed in septal portion of anterior wall (65%), septal portion of posterior wall (62%) and apical wall (73%). Defect score was higher in septal portion of anterior wall (p < 0.001), septal portion of posterior wall (p < 0.01) and apical wall (p < 0.01) than in the ventricular septum. This result indicates that in hearts with ASH, 123I-BMIPP image reveals severely impaired fatty acid metabolism in these regions. With the reference of the previous report about histologic features in necropsy hearts with HCM, myocardial fatty acid metabolic disorder shown by reduced 123I-BMIPP uptake is closely related to the histological abnormalities in hearts with HCM.

[Posterolateral extradural approach for total excision of spinal meningeal cyst (type Ia): case report]

Lateral thoracic meningocele is an uncommon disorder known to occur with high frequency in patients with neurofibromatosis. We report a case not accompanied by neurofibromatosis and describe the operative technique utilizing a posterolateral extradural approach. A 41-year-old man was referred to our cardiologic clinic for severe anterior chest pain. Plain chest X-ray demonstrated an oval mass lesion in the right 9th to 10th thoracic paravertebral region. Magnetic resonance imaging revealed a cystic mass at the 10th thoracic intervetebral foramen without distortion of the spinal cord. Signal intensity of the cystic mass was the same as the cerebrospinal fluid around the spinal cord. In the prone position, laminotomy of the 10th vertebral only was carried out. A pulsatile round mass in continuity with the dura mater was exposed. The wall of the sac, which was thickened with CSF, was identified. The neck of the menigocele was ligated with the help of an aneurysm needle. The patient's severe chest pain disappeared postoperatively.

Cell counts in peripheral blood and bone marrow of male C.B-17 scid/scid mice

Blood cell and bone marrow cell counts were carried out for male C.B-17 scid/scid (SCID) mice aged 3, 6, 9, 18 and 26 weeks and the values were compared with those in C.B-17 +/+ (C.B-17) mice. In the peripheral blood, SCID mice had markedly low numbers of leucocytes and lymphocytes throughout the study. In the bone marrow, SCID mice had relatively low levels of erythroblasts at an early age, low levels of lymphocytes and plasma cells were absent.

[Pulmonary tuberculosis complicated with tuberculosis of oral mucosa, mandible and cervical lymph nodes]

A case of pulmonary tuberculosis complicated with tuberculous of oral mucosa, mandible and cervical lymph nodes in 53-year-old man is reported. He was firstly treated for right side dental caries. He also received routinely an empiric antibiotic therapy, but discharge of pus continued. Then, pain of oral cavities spread to the right shoulder. The diagnosis of oral mucosa, osteomyelitis of mandible and lymph node tuberculosis was made by the histological examination of biopsy specimens and positive smear test for M. tuberculosis in granulation. The chest X-ray film showed multiple nodular shadows in bilateral lungs. The combination of INH, RFP and SM was applied initially and then SM was replaced by CS due to its side effect. Negative smear test for M. tuberculosis of oral mucosa was achieved five months after the initiation of treatment.

Possible role of thromboxane A2 in hyperresponsiveness of isolated rat lung tissue in a Sephadex-induced eosinophilia model

Antigen-stimulated contraction and release of chemical mediators were examined in saline- or Sephadex-treated rat lung parenchymal strips. Sephadex treatment caused eosinophilia in the blood and the lung tissue. Antigen challenge of the isolated parenchymal strips in Sephadex-treated rat was followed by passive sensitization, resulted in an augmented contraction and elevated releases of thromboxane (TX) B2 and peptide-leukotrienes (p-LTs) in bath fluid compared with those of saline-treated control. Although 5-hydroxytryptamine (5-HT) and histamine were significantly released after antigen challenge, the levels were not different between saline- and Sephadex-treated groups. DP-1904, a selective thromboxane synthetase inhibitor, and methysergide but not atropine significantly reduced the augmented contraction and inhibited the elevated TXB2 release in the Sephadex-treated group. Similar increased contraction and the elevated TXB2 release above were observed when Sephadex-treated rat lung strips were stimulated by exogenous 5-HT and LTD4. These augmented contractions were closely correlated with the increase in TXB2 level (r = 0.83; p < 0.01). In addition, contraction to U-46619, a thromboxane mimetic, was significantly greater in Sephadex-treated rat lung strips. Our results indicate that the ability of Sephadex-treated rat lung tissue to synthesize newly generated mediators such as TXA2 and p-LTs is increased, and the spasmogenic susceptibility of the lung tissue to TXA2 itself is modified by Sephadex treatment, suggesting these are due to the augmented contraction in an established hyperresponsiveness state induced by Sephadex.