Involvement of DNA polymerase delta and/or epsilon in joining UV-induced DNA single strand breaks in human fibroblasts (comparison of effects of butylphenyldeoxyguanosine with aphidicolin)

DNA polymerases involved in ultraviolet (UV)-induced DNA repair were studied in human fibroblasts using the inhibitors of DNA polymerases, aphidicolin which inhibits DNA polymerases alpha, delta and epsilon, and butylphenyldeoxyguanosine (BuPGdR) which inhibits DNA polymerase alpha strongly and weakly inhibits delta and epsilon. Both inhibitors inhibited replicative DNA synthesis in a dose dependent manner as measured by thymidine incorporation. However, BuPGdR did not accumulate single strand breaks in cells irradiated with 5 J/m2 UV-light even at the highest dosage tested, indicating that BuPGdR does not inhibit DNA repair. On the other hand, aphidicolin accumulated single strand breaks in UV-light irradiated cells. These results suggest that DNA polymerase delta and/or epsilon are mainly involved in UV-induced DNA repair.

Functional anatomy of taste perception in the human brain studied with positron emission tomography

Regional cerebral blood flow (rCBF) was measured with positron emission tomography (PET) in 10 normal volunteers with the purpose of measuring rCBF changes related to taste physiology. Discrimination of 0.18% saline from pure water was associated with significantly increased rCBF values in the thalamus, the insular cortex, the anterior cingulate gyrus, the parahippocampal gyrus, the lingual gyrus, the caudate nucleus, and the temporal gyri. The results indicate that rCBF changes in these structures may reflect oral exposure to salt.

[Pathogenesis of spontaneous nephrosis in mice--urinary protein in nephrotic mice]

There is a paucity of model animals for naturally occurring nephrosis. The nephrotic mouse strain (ICGN) found from ICR mouse colony at National Institute of Health could be one of the most suitable model for nephrosis. We maintained the strain of mice which was originated from the hybrid between the nephrotic ICGN mice and ICR mice. Nephrosis is diagnosed with the presence of albumin band on SDS-PAGE of the urine. The detection of urinary albumin using SDS-PAGE could be valuable for early diagnosis of nephrosis in the mice. The total urinary protein concentration was determined on the course of nephrosis. The nephrotic mice showed slightly higher protein concentration between 2 and 6 days old as compared to control mice. Until 16 day old, it was maintained relatively low level. Thereafter, the total urinary protein increased gradually. However the diagnosis of nephrosis with total urinary protein alone may be limited due to the major urinary protein which can be detected even in normal rodents.

[Urethral opening pressure as a parameter for introduction of the proper voiding modality in myelodysplastic patients]

To introduce the proper voiding modality to patients with myelodysplasty, urethral opening pressure (UOP), an intravesical pressure just at the beginning urine flows out beyond the external urethral sphincter, was measured in 63 myelodysplastic patients. Among 45 renal units with any morphological or functional changes at the first UOP measurement, 37 units (82.2%) were included in the high UOP group (> or = 35 cmH2O). And among 41 ureters with VUR of more than grade 2, 32 (78.0%) were in the high UOP group. In addition, deformity of the urinary bladder was observed in 36 patients, and 26 (72.2%) of these bladders showed high UOP values. Therefore, all the patients could be divided into two groups: high UOP group (> or = 35 cmH2O, 28 cases) and low UOP group (< 35 cmH2O, 35 cases). Twenty-three patients (82.1%) with high UOP values had been mainly treated with clean intermittent catheterization (CIC). In contrast, 24 patients (68.6%) with low UOP values had been allowed to urinate by Credè' or Valsalva's method. In the followup study for 40 to 44 months, patients in the CIC group obtained good prognosis as for morphological or functional changes of the urinary tract. On the other hand, patients in the Credè' or Valsalva's method group showed a significantly higher deterioration rate in the high UOP group (80.0%) than that in the low UOP group (9.1%) (p < 0.005). From these results, hopely that in myelodysplastic patients with the underactive detrusor, CIC may be introduced for low pressure voiding to those who show high UOP values as early as possible. On the other hand, those who show low UOP values may be managed with Credè' or Valsalva's method as well as CIC. Thus, UOP is considered a possible prognostic factor for the morphological and functional changes of the urinary tract, which may be a useful parameter in decision of voiding modalities in myelodysplastic patients.

Cellular localization of type II Ca2+/calmodulin-dependent protein kinase in the rat basal ganglia and intrastriatal grafts derived from fetal striatal primordia, in comparison with that of Ca2+/calmodulin-regulated protein phosphatase, calcineurin

We investigated immunohistochemically the cellular localization of multifunctional type II Ca2+/calmodulin-dependent protein kinase in the rat basal ganglia and intrastriatal grafts derived from fetal striatal primordia, in comparison with that of calcineurin, a reliable marker for striatal medium-sized spinous neurons. The type II Ca2+/calmodulin-dependent protein kinase-positive neurons were of medium size, with a mean diameter of 16.1 +/- microns (average +/- S.D., n = 72, range 13.6-18.3 microns) and comprised approximately 70% of the total neuronal population in the striatum. Light microscopy showed that the type II Ca2+/calmodulin-dependent protein kinase-positive cells had round, triangular or polygonal cell bodies with relatively little cytoplasm. Analysis of serial sections showed that type II Ca2+/calmodulin-dependent protein kinase and calcineurin immunoreactivities were co-localized in the striatal neurons examined with a similar distribution pattern. Type II Ca2+/calmodulin-dependent protein kinase-positive cells were always immunoreactive for calcineurin and cells negative for type II Ca2+/calmodulin-dependent protein kinase showed no apparent calcineurin immunoreactivity. Type II Ca2+/calmodulin-dependent protein kinase-positive nerve fibers in the globus pallidus and substantia nigra almost disappeared following striatal ischemic injury produced by transient middle cerebral artery occlusion and cerebral hemitransection, respectively, suggesting that these immunopositive fibers were striatal projections. Thus, most type II Ca2+/calmodulin-dependent protein kinase-positive neurons in the rat striatum are considered to be of the medium-sized spinous type. Type II Ca2+/calmodulin-dependent protein kinase or calcineurin immunoreactivity was also observed in a large number of neurons in transplants derived from fetal striatal primordia grafted into striatal ischemic lesions. In addition, type II Ca2+/calmodulin-dependent protein kinase- or calcineurin-immunoreactive nerve fibers appeared in the deafferented globus pallidus of the host rats, suggesting that the striatopallidal pathway was reformed by striatal projection neurons of the transplants. This finding may also indicate that Ca2+/calmodulin-regulated enzymes are useful for tracing striatal projection fibers as endogenous marker proteins.

Effects of risperidone on phencyclidine-induced behaviors: comparison with haloperidol and ritanserin

In this study, we investigated whether risperidone, a serotonin-S2A (5-HT2A)/dopamine-D2 (D2)-receptor antagonist, inhibits phencyclidine (PCP)-induced stereotyped behaviors in comparison with haloperidol and ritanserin. Moreover, we also attempted to investigate the effects of these antipsychotics on the contents of dopamine, serotonin (5-HT) and their metabolites in rat striatum and frontal cortex. In rats, PCP (5 mg/kg, i.p.) caused hyperlocomotion and stereotyped behaviors, including sniffing, head-weaving, backpedalling and turning. Both resperidone (0.8-2.4 mg/kg, p.o.) and haloperidol (0.3-1.0 mg/kg, p.o.) inhibited these behaviors, except for backpedalling, in a dose-dependent manner. PCP (10 mg/kg, i.p.) produced hyperlocomotion and stereotyped behaviors, including rearing, sniffing head-twitch, backpedalling and turning. Risperidone (0.8-2.4 mg/kg, p.o.) inhibited both hyperlocomotion and PCP-induced behaviors, except for backpedalling, while ritanserin (3-10 mg/kg, p.o.) inhibited only the head-twitch. These results suggest that risperidone may have an antipsychotic effect on schizophrenia as well as PCP psychosis in humans by exerting a mixed 5-HT2A/D2 antagonism. Neurochemically, the increasing effects of risperidone on the content of DOPAC and the ratio of DOPAC to dopamine in the striatum were lower than those of haloperidol. These findings may support the view that the extrapyramidal side effects of risperidone are lower than those of haloperidol in clinical situations.

Occurrence of heat shock response in deafferented neurons in the substantia nigra of rats

The substantia nigra is innervated by massive inhibitory GABAergic projections from the striatum and globus pallidus, deafferentation of which is supposed to lead to anterograde trans-synaptic degeneration of the nigral neurons. An immunohistochemical method was used to examine the induction of 72,000 mol. wt heat shock protein in the substantia nigra following cerebral hemitransection or transient middle cerebral artery occlusion. At three and four days post-transection, strong immunoreactivity for 72,000 mol. wt heat shock protein was found in the ipsilateral substantia nigra pars reticulata. Light microscopic observation revealed a number of pars reticulata neurons showing strong immunoreactivity for 72,000 mol. wt heat shock protein in their perikarya and proximal processes. In addition, Golgi-like stained neurons with dystrophic features were occasionally observed in the ipsilateral substantia nigra pars reticulata. The immunoreactivity for 72,000 mol. wt heat shock protein in the ipsilateral pars reticulata gradually declined and almost disappeared by 15 days after transection. No apparent induction of 72,000 mol. wt heat shock protein was found in the substantia nigra pars compacta throughout the time period examined. Massive striatal ischemic injury produced by transient middle cerebral artery occlusion also induced expression of 72,000 mol. wt heat shock protein in the pars reticulata neurons three and four days postoperatively. These findings suggest that deafferentation of the striatal or striatopallidal inputs per se is a harmful stress for the substantia nigra pars reticulata neurons, inducing 72,000 mol. wt heat shock protein synthesis. The present data may contribute to our understanding of the molecular basis of the pathomechanism of the transneuronal regression of substantia nigra pars reticulata neurons, which may occur after removal of inhibitory GABAergic inputs.

Transcriptional regulation of human transglutaminase1 gene by signaling systems of protein kinase C, RAR/RXR and Jun/Fos in keratinocytes

Transglutaminase1 (TGase1) gene is expressed at the late stage of terminal differentiation of epidermal keratinocytes. 12-O-tetradecanoylphorbol-13-acetate (TPA) markedly induced the luciferase activity in cultured rat keratinocytes. FRSK cells, transfected with a luciferase reporter plasmid containing the 0.82-kb 5'-flanking region of the human TGase1 gene, but hardly in non-keratinocytic cells. The TPA-induced luciferase activity was suppressed by retinoic acid, 9-cis retinoic acid, and 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H-7). Co-transfection with expression plasmids for c-jun and/or c-fos showed that Jun itself induced the luciferase activity, whereas Fos inhibited both the basal and TPA-induced luciferase activity. These results suggested that the signaling systems including protein kinase C, retinoic acid/retinoid-X receptors, and Jun/Fos regulate the transcription of the TGase1 gene.

Analysis of auditory brain stem response with lidocaine injection into the cerebrospinal fluid in rats

Auditory brain stem response (ABR) was recorded in 10 rats with total spinal anesthesia induced by injection of 2% lidocaine hydrochloride into the subarachnoid space through the skull. The ABR disappeared immediately (within 4 minutes) after the injection of 13.3 to 40.0 mg/kg lidocaine. The disappearance started with the later waves of the ABR. After cessation of the injection, the ABR reappeared and recovered progressively from wave I to wave IV. The effect of lidocaine on the ABR was reversible and extended in the acoustic nerve to the midbrain.

A novel substrate for insulin-sensitive serine/threonine kinase in intact cells

We have studied insulin-stimulated threonine phosphorylation of cellular proteins by immunoblotting and immunoprecipitation using antiphosphothreonine antibody (anti-P-Thr). A 50-kilodalton protein (p50) was found to be greatly phosphorylated on threonine residues upon insulin stimulation in intact rat hepatoma cells (Fao) and Chinese hamster ovary cells overexpressing human insulin receptor (CHO-HIR). Insulin induced threonine phosphorylation of this protein in a dose-dependent manner, with an ED50 of 3-6 x 10(-9) M. The 50-kilodalton phosphoprotein (pp50) was detectable 20 min after exposure of the cells to insulin, and phosphorylation reached a maximum after 90 min. Immunoprecipitation of pp50 with anti-P-Thr required extraction of the cellular proteins with sodium dodecyl sulfate and dithiothreitol, and subcellular fractionation of the cells revealed that pp50 is present in the membrane fraction, implying that pp50 is a protein integrated into the membrane component in the cells. Tryptic phosphopeptide mapping of the pp50 was distinct from that of the insulin receptor beta-subunit. Phosphoamino acid analysis of the pp50 demonstrated that insulin increased phosphorylation, mainly of threonine and moderately of serine, whereas pp50 did not contain phosphotyrosine. Cycloheximide, a protein synthesis inhibitor, did not affect the insulin-induced appearance of pp50 in the cells. pp50 was not detectable in A431 cells and KB cells stimulated by epidermal growth factor. These data suggest that p50 is a novel endogenous substrate for insulin-sensitive serine/threonine kinase in intact cells.

A phase II clinical trial of recombinant human tissue-type plasminogen activator against cerebral vasospasm after aneurysmal subarachnoid hemorrhage

The results of a Phase II clinical trial of intrathecal recombinant tissue-type plasminogen activator for the prevention of vasospasm were reported. The subjects were 53 patients with aneurysmal subarachnoid hemorrhage (SAH), Groups 2 to 4 in Fisher's preoperative computed tomography classification and Grades II to IV in the Hunt-Kosnik classification. Twenty-four hours after surgery, tissue-type plasminogen activator (TD-2061) was intracisternally administered via a catheter (0.1, 0.2, or 0.4 mg, three times daily for 5 days). The clot-dissolving effects assessed as "effective" and "markedly effective" were virtually the same in the 0.1- and 0.2-mg groups (66.7% and 64.3%, respectively) but slightly lower (53.3%) in the 0.4-mg group, suggesting an adequate effect in the 0.1- and 0.2-mg groups. Severe angiographic vasospasm was not observed in any of three groups. No intergroup differences were noted in the incidence of symptomatic vasospasm, low density on computed tomography 1 month after SAH, and functional prognosis. Bleeding complications were noted in 4 patients (7.5%), including 1 case of SAH in the low 0.1-mg group, 2 cases of SAH in the 0.2-mg group, and 1 case of epidural hematoma in the 0.4-mg group. In overall safety rating, 3 cases with increased SAH and 1 case of epidural hematoma were assessed as "safety doubtful." Other minor side effects such as headache and hepatic dysfunction attributed to the effect of other simultaneously used drugs were assessed as "almost safe," and the rate of "almost safe" and "better" for all dose groups was about 90%, suggesting a safe dose level for all groups. These results suggest that repeated intrathecal administration of tissue-type plasminogen activator is useful for preventing vasospasm even in the low dose of 0.1 mg.

Production and release of polyphosphate by a genetically engineered strain of Escherichia coli

A recombinant strain of Escherichia coli MV1184, which contains plasmid-borne genes encoding the phosphate-specific transport (Pst) system and polyphosphate (polyP) kinase, accumulated high levels of Pi and released polyP into the medium. PolyP could be separated from the culture supernatant by DEAE-Toyopearl 650M chromatography and identified by high-resolution 31P nuclear magnetic resonance spectroscopy. Once E. coli recombinants accumulated high levels of polyP, they released polyP concomitantly with Pi uptake. PolyP release did not accompany the decrease in the cell density, indicating that it is not simply a result of cell lysis. PolyP release ceased when Pi became depleted in the medium and resumed upon addition of Pi to the medium. When Pi uptake was inhibited by 0.1 mM carbonyl cyanide m-chlorophenylhydrazone (CCCP), no polyP release was observed. Furthermore, neither Pi uptake nor polyP release occurred when cells were incubated at 4 degrees C. These findings suggest that the occurrence of polyP release is a possible mechanism that limits a further increase in the cellular polyP concentration in E. coli recombinants. High-resolution 31P nuclear magnetic resonance spectroscopy also detected a surface pool of polyP in intact cells of the E. coli recombinant. The polyP resonance increased when cells were treated with EDTA and broadened upon the addition of a shift reagent, praseodymium. Although the mechanism of surface polyP accumulation is unclear, surface polyP seems to serve as the source for polyP release.

Plasma levels of soluble fibrin in patients with malignancy-associated disseminated intravascular coagulation

Disseminated intravascular coagulation (DIC) is one of the most critical complications of malignant diseases. It is conventionally diagnosed by a decrease in platelets and an increase in fibrin/fibrinogen degradation products (FDP). Recently, an immunological assay was developed that can directly quantify the amount of soluble fibrin (SF) formed in the blood. This study examined this assay system in the diagnosis of DIC and found that it is a good indicator of both fibrin formation and of DIC. Plasma levels of SF correlated well with the DIC score, which is determined according to the 'DIC Scoring Guideline' proposed by the DIC Study Group under the Japanese Ministry of Public Welfare in 1988. It also correlated well with the serum levels of FDP. Normal values of plasma SF ranged between 0 and 9.50 micrograms/ml. Interestingly, values of SF in females tended to increase with age, for reasons that are not yet determined.

[Anatomical consideration of anesthetic dispersion into abdominal cavity causing broad unilateral anesthesia after inadvertent local anesthetic infusion into endothoracic fascia]

Recently we reported a case of inadvertent migration of an epidural catheter into the endothoracic fascia. Anesthetic injection into the fascia brought a broad unilateral analgesia. To clarify the mechanism of anesthesia. We studied how the anesthetic agent spreads into the abdominal cavity from the endothoracic fascia. The crimson dye, the substitute of the anesthetic agent, reached the transversial fascia in the abdominal cavity through medial and lateral arcuate ligament. Subcostal nerve, iliohypogastric nerve, ilioinguinal nerve, genitofemoral nerve and lateral femoral cutaneous nerve were found to be in the course of dye dispersion. The renal adiposal fascia plays a role of a reservoir for the anesthetic agent and prevents the further anesthetic dispersion.

[Influence of age on cardiac pump function during laparoscopic cholecystectomy--measurements by ear densitography]

Using ear densitography, consisting of photoelectric plethysomography and Holter electrocardiography, we measured systolic time intervals (STI) in 21 patients, ASA class 1 and 2, undergoing laparoscopic cholecystectomy using CO2 insufflation under general anesthesia (neuroleptanesthesia with isoflurane in air, FIO2 0.5). The patients were divided into two groups: Y-group (10 patients under 59 years of age) and O-group (11 patients over 60 years of age). We investigated the influence of age on cardiac pump function during pneumoperitoneum non-invasively. Y-group showed improvement of cardiac pump function (reduction of PEP/LVET) from 30 minutes after the beginning of insufflation and quick recovery of cardiac function immediately after deflation. O-group showed a tendency of increasing PaCO2 and arterial diastolic pressure, and delayed recovery of cardiac function (elongation of PEP at 60 minutes, and increase of PEP/LVET at 60 and 90 minutes, respectively, after insufflation). Hypertension and tachycardia were apparent immediately after pneumoperitoneum in the O-group. We conclude that special care and monitoring are mandatory for the aged patients with impaired cardiac or respiratory function during laparoscopic surgery.

A possible role of tyrosine kinases in the regulation of muscarinic receptor-activated cation channels in guinea pig ileum

We investigated the effects of inhibitors for tyrosine kinases and phosphatases on the muscarinic receptor-activated nonselective cationic current. With nystatin-perforated whole-cell recording, the tyrosine kinase inhibitor genistein (1 approximately 10 micrograms/ml) reduced the amplitude of currents evoked by iontophoretically applied acetylcholine in a dose-dependent manner, the maximum inhibition being to about 46% of the control. In contrast, daidzein (10 micrograms/ml), an inactive analog of genistein, exerted little effect. These effects were unchanged when the cationic current was activated by internal perfusion of GTP gamma S (50 microM) bypassing the muscarinic receptor. A potent phosphatase inhibitor, orthovanadate (30 approximately 100 microM), on the other hand, increased the GTP gamma S-induced cationic current. These results suggest that tyrosine phosphorylation may be essential to regulate the Ca mobilization associated with muscarinic receptor-operated nonselective cation channels.

Phenotypic changes of AADC-only immunopositive premammillary neurons in the brain of laboratory shrew Suncus murinus by systemic administration of monoamine precursors

After 5-hydroxy-L-tryptophan (5-HTP) and L-3,4-dihydroxyphenylalanine (L-DOPA) were injected i.p. in the laboratory shrew Suncus murinus, immunocytochemical and immunofluorescence studies were conducted on continuous or same sections of the brain, using specific anti-tyrosine hydroxylase (TH), anti-aromatic L-amino acid decarboxylase (AADC), anti-dopamine (DA) and anti-serotonin (5-HT) antisera which were produced in our laboratory. The results of double-staining by the immunofluorescence method as well as immunoelectron microscopy strongly indicate that the cells of the premammillary nucleus of the laboratory shrew brain (AADC-only-positive neurons) are capable of synthesizing DA and 5-HT simultaneously upon simultaneous administration of L-dopa and 5-HTP.

Biphasic effect of estrogen on neuronal constitutive nitric oxide synthase via Ca(2+)-calmodulin dependent mechanism

Estrogen is known to retard the development of atherosclerosis and to work in the brain, but the mechanism of hormonal action is completely unknown. We investigated the effect of estrogen on the activity of neuronal constitutive nitric oxide synthase (NNOS). A low concentration of estrogen (10(-10)(-7) M) enhanced the activity of homogenates of the cytosol fraction of rabbit cerebellums and also that of partially purified NNOS, and high dose (10(-6)(-5) M) attenuated them. The study using estrogen receptor antagonists, tamoxifen, clomiphene, and ICI182780 suggested that estrogen receptor did not relate significantly to those effects of 17 beta-estradiol. 17 alpha-estradiol or progesterone did not change significantly it in low doses, although moderately inhibited it in high doses. Estrogen enhanced the fluorescence of dansyl-calmodulin in low doses and attenuated it in high doses, suggesting that estrogen affects Ca(2+)-calmodulin directly. This study demonstrated that estrogen has a biphasic effect on the activity of NNOS through a Ca(2+)-calmodulin.

Secretion of TNF from a rat mast cell line is a brefeldin A-sensitive and a calcium/protein kinase C-regulated process

Stimulated mast cells and cognate cultured cell lines produce and secrete a variety of cytokines including TNF. Because the mechanism by which cytokines are delivered to the external milieu is unknown, the release of TNF was studied in a rat mast cell line (RBL-2H3 cells). In these cells, TNF was not constitutively expressed nor incorporated into secretory granules but was generated de novo upon cell stimulation. It was then released by a process analogous to constitutive secretion in that brefeldin A, an agent known to disrupt Golgi membranes in these cells, inhibited this release without inhibiting release of secretory granules. Unlike constitutive secretion, however, the secretion of TNF was highly regulated by Ca2+ and protein kinase C. Studies with various stimulants and inhibitors indicated that simultaneous mobilization of Ca2+ and activation of protein kinase C were sufficient signals for secretion although optimal production of TNF may be dependent on additional synergistic signals. Because suppression of Ca2+ mobilization or inhibition of protein kinase C alone abrogated TNF secretion, the process may be amenable to therapeutic intervention.

Secretion of TNF from a rat mast cell line is a brefeldin A-sensitive and a calcium/protein kinase C-regulated process

Stimulated mast cells and cognate cultured cell lines produce and secrete a variety of cytokines including TNF. Because the mechanism by which cytokines are delivered to the external milieu is unknown, the release of TNF was studied in a rat mast cell line (RBL-2H3 cells). In these cells, TNF was not constitutively expressed nor incorporated into secretory granules but was generated de novo upon cell stimulation. It was then released by a process analogous to constitutive secretion in that brefeldin A, an agent known to disrupt Golgi membranes in these cells, inhibited this release without inhibiting release of secretory granules. Unlike constitutive secretion, however, the secretion of TNF was highly regulated by Ca2+ and protein kinase C. Studies with various stimulants and inhibitors indicated that simultaneous mobilization of Ca2+ and activation of protein kinase C were sufficient signals for secretion although optimal production of TNF may be dependent on additional synergistic signals. Because suppression of Ca2+ mobilization or inhibition of protein kinase C alone abrogated TNF secretion, the process may be amenable to therapeutic intervention.

[Drug distribution and antitumor effect of bleomycin incorporated in poly DL-lactic acid in rats]

Two bleomycin (BLM)-containing agents (BLM-PLA, BLM-SOL) were prepared, and the drug distribution and antitumor effect were studied. BLM-PLA is an agent in which BLM is incorporated into biodegradable low-molecular-weight polylactic acid, and BLM-SOL is an aqueous solution of BLM. BLM-PLA or BLM-SOL was subcutaneously administered in the back of rats. When BLM-PLA was implanted, high BLM activity of the connective tissues near the implants was maintained for 2 weeks. On the other hand, BLM activity was very low when BLM-SOL was administered. The effects of BLM-PLA, BLM-SOL and nontreatment on tumor growth and survival time were compared using subcutaneous tumor of Yoshida sarcoma in 21 rats each. The survivors and mean survival time in BLM-PLA group, BLM-SOL group and nontreatment group was 14 and 44.6 days, 5 and 23.7 days, and 0 and 11.3 days, respectively. BLM-PLA was superior to BLM-SOL in both drug distribution and antitumor effect, and consequently BLM-PLA could be a useful tool in loco-regional chemotherapy.

[Incidence rates of cerebral palsy, mental retardation and Down syndrome in Sodegaura City, Chiba Prefecture]

For the purpose of early detection and early habilitation for developmentally handicapped children, we started medical screening in 1978 for pediatric neurological diseases among children in Sodegaura City, Chiba Prefecture with a total population of about 50,000. A statistical analysis were performed for the incidence of cerebral palsy (CP), mental retardation (MR, I.Q < 70) and Down syndrome (Down). The number of liveborn babies during 1978-1987 was 5,070. The number of patients with CP, MR and Down were 11, 44 and 5 respectively. The incidence rates of CP, MR and Down were 0.217%, 0.868% and 0.099% respectively, which were almost equal to those recent reports. The rate of perinatal brain damage with CP was 81.8%. The incidence rates of mild MR (MMR, I.Q 69-50) and severe MR (SMR, I.Q < 50) were 0.512% and 0.355% respectively. The SMR rate was almost equal to recent reports, and the MMR rate was different from some reports. The rates of prenatal brain damage, perinatal brain damage, postneonatal brain damage and unknown origin with MR were 20.5%, 22.7%, 4.5% and 34.1% respectively. The rate of perinatal disorders, which play some role in the etiology of MR, was 18.2%. Even now, the perinatal disorders play a major role of CP and MR. Therefore the progress of perinatal medicine is strongly desired.

Lack of any positive effect of intestinal metaplasia on induction of gastric tumors in Wistar rats treated with N-methyl-N-nitrosourea in their drinking water

The influence of intestinal metaplasia on gastric cancer induction was examined in five-week-old male Wistar:Crj rats. The animals were first treated with two 10 Gy doses of X-rays to the gastric region at a 3-day interval (total 20 Gy) and then, starting two months after the irradiation, received 100 ppm N-methyl-N-nitrosourea (MNU) in their drinking water for 15 weeks. Thereafter they were maintained for 37 weeks with or without a dietary 1% sodium chloride (NaCl) supplement. The incidences of gastric adenocarcinomas in the MNU or MNU plus NaCl groups were significantly higher than in animals receiving X-rays plus MNU with or without NaCl. Intestinal metaplasias and the numbers of alkaline phosphatase (ALP)-positive foci were significantly increased in the X-ray irradiation groups but the numbers of ALP-positive foci were not increased with or without 1% NaCl. An inverse relationship between incidences of gastric tumors and intestinal metaplasias was apparent. The present experiment thus showed that the presence of intestinal metaplasia does not exert a positive influence on induction of gastric neoplasia by MNU in the rat.