High doses of intravenous immunoglobulin stimulate regulatory T cell and suppress natural killer cell in women with recurrent pregnancy loss

The aim was to evaluate whether natural killer (NK) cells and regulatory T (Treg) cells were involved in mechanisms underlying beneficial effects of a high dose of intravenous immunoglobulin (IVIG) on recurrent pregnancy losses (RPL) of unexplained etiology. In a double-blind, randomized, placebo-controlled trial of IVIG (400 mg/kg, for 5 days in 4-6 weeks of gestation) in women with RPL, blood samples were collected pre-infusion, one week after infusion (1 w), and eight weeks of gestation/when miscarried (8 w). Levels of NK and Treg cells in peripheral blood were compared between women with IVIG (n = 50) and placebo (n = 49), and between women with IVIG who gave live birth (n = 29) and those who had miscarriage with normal chromosome (n = 12). Effector Treg cell percentages in IVIG group at 1 w (mean 1.43 % vs. 1.03 %) and at 8 w (1.91 % vs. 1.18 %) were higher than those in placebo group (p < 0.01). Total Treg cell percentages in IVIG group at 1 w (4.75 % vs. 4.08 %) and at 8 w (5.55 % vs. 4.47 %) were higher than those in placebo group (p < 0.05). In women with live birth, total Treg cell percentages increased at 8 w (5.52 %, p < 0.001) compared with pre-infusion (4.54 %) and 1 w (4.47 %), while NK cell activity decreased at 1 w (20.18 %, p < 0.001) compared with pre-infusion (26.59 %). IVIG increased Treg cell percentages and suppressed NK cell activity very early in pregnancy, and these were associated with subsequent live birth. Stimulation of Treg cells and suppression of NK cell activity very early in pregnancy may be a mechanism of pharmacological effects of high dose IVIG.

Intravenous immunoglobulin treatment in women with four or more recurrent pregnancy losses: A double-blind, randomised, placebo-controlled trial

BACKGROUND

There is no effective treatment for women with unexplained recurrent pregnancy loss (RPL). We aimed to investigate whether treatment with a high dose of intravenous immunoglobulin (IVIG) in early pregnancy can improve pregnancy outcomes in women with unexplained RPL.

METHODS

In a double-blind, randomised, placebo-controlled trial, women with primary RPL of unexplained aetiology received 400 mg/kg of IVIG daily or placebo for five consecutive days starting at 4-6 weeks of gestation. They had experienced four or more miscarriages except biochemical pregnancy loss and at least one miscarriage of normal chromosome karyotype. The primary outcome was ongoing pregnancy rate at 22 weeks of gestation, and the live birth rate was the secondary outcome. We analysed all women receiving the study drug (intention-to-treat, ITT) and women except those who miscarried due to fetal chromosome abnormality (modified-ITT). This study is registered with ClinicalTrials.gov number, NCT02184741.

FINDINGS

From June 3, 2014 to Jan 29, 2020, 102 women were randomly assigned to receive IVIG (n = 53) or placebo (n = 49). Three women were excluded; therefore 50 women received IVIG and 49 women received placebo in the ITT population. The ongoing pregnancy rate at 22 weeks of gestation (31/50 [62·0%] vs. 17/49 [34·7%]; odds ratio [OR] 3·07, 95% CI 1·35-6·97; p = 0·009) and the live birth rate (29/50 [58·0%] vs. 17/49 [34·7%]; OR 2·60, 95% CI 1·15-5·86; p = 0·03) in the IVIG group were higher than those in the placebo group in the ITT population. The ongoing pregnancy rate at 22 weeks of gestation (OR 6·27, 95% CI 2·21-17·78; p < 0·001) and the live birth rate (OR 4·85, 95% CI 1·74-13·49; p = 0·003) significantly increased in women who received IVIG at 4-5 weeks of gestation as compared with placebo, but these increases were not evident in women who received IVIG at 6 weeks of gestation. Four newborns in the IVIG group and none in the placebo group had congenital anomalies (p = 0·28).

INTERPRETATION

A high dose of IVIG in very early pregnancy improved pregnancy outcome in women with four or more RPLs of unexplained aetiology.

FUNDING

The Japan Blood Products Organization.

Spontaneously conceived heterotopic pregnancy with abdominal pregnancy implanted on the vesicouterine pouch: A case report and literature review

We report the case of a 36-year-old woman with spontaneously conceived heterotopic pregnancy with abdominal pregnancy. She visited the hospital at 5 weeks and 4 days of gestation and transvaginal ultrasonography revealed a normal intrauterine pregnancy. Two days later, she was urgently transported to the hospital due to extreme abdominal pain. Emergent laparotomy was performed to investigate the cause of massive intraperitoneal bleeding, which was confirmed to have been due to an abdominal pregnancy that implanted on the vesicouterine pouch. The hematic mass, including chorionic villi, was successfully removed from the peritoneum. The subsequent course of the intrauterine pregnancy was uneventful and a healthy baby was born at term. To the best of our knowledge, this is an extremely rare case report of a spontaneously conceived heterotopic abdominal pregnancy, in which the intrauterine pregnancy showed a successful outcome despite the collapse of the abdominal pregnancy at a very early stage.

P2621Clinical safety and efficacy of tolvaptan for acute phase therapy in patients with low-flow severe aortic stenosis

Background

Conventional diuretic therapy for low-flow (LF) severe aortic stenosis (SAS) often has an inadequate effect or causes hemodynamic instability. Tolvaptan is used for acute heart failure in addition to conventional diuretics in Japan, and it does not cause intravascular dehydration.

Purpose

This study aimed to retrospectively investigate the safety and efficacy of tolvaptan in the acute phase patients with SAS and compared LF-SAS with normal-flow (NF) SAS.

Methods

56 consecutive SAS patients are analyzed. The primary endpoints were adverse clinical events (death, worsening heart failure, worsening renal failure, fatal arrhythmia, cardiogenic or hypovolemic shock, and use of inotropic agents) and the volume of urine and fluid balance within 48 hours of tolvaptan administration (Figure).

Results

Among 56 patients, 16 had LF-SAS (29%), and 40 had NF-SAS (71%). Severe adverse clinical events were not observed 48 hours after tolvaptan administration. In both groups, the urine volume significantly increased after tolvaptan administration in comparison to 24 hours before tolvaptan administration (both, p<0.01). There were no changes in the urine volume during the initial 24 and 48 hours. In the LF-SAS group, tolvaptan resulted in a significant decrease in fluid balance during the initial 24 and 48 hours compared to 24 hours before tolvaptan administration (p<0.05).

Treatment and data collection protocols

Conclusion

Adding tolvaptan to conventional treatment leads to an increase in urine output and a decreased fluid balance without hemodynamic instability in patients with LF-SAS.

Acknowledgement/Funding

None

Maternal age, history of miscarriage, and embryonic/fetal size are associated with cytogenetic results of spontaneous early miscarriages

PURPOSE

To clarify the associations of the maternal age, history of miscarriage, and embryonic/fetal size at miscarriage with the frequencies and profiles of cytogenetic abnormalities detected in spontaneous early miscarriages.

METHODS

Miscarriages before 12 weeks of gestation, whose karyotypes were evaluated by G-banding between May 1, 2005, and May 31, 2017, were included in this study. The relationships between their karyotypes and clinical findings were assessed using trend or chi-square/Fisher's exact tests and multivariate logistic analyses.

RESULTS

Three hundred of 364 miscarriage specimens (82.4%) had abnormal karyotypes. An older maternal age was significantly associated with the frequency of abnormal karyotype (p_trend < 0.001), particularly autosomal non-viable and viable trisomies (p_trend 0.001 and 0.025, respectively). Women with ≥ 2 previous miscarriages had a significantly lower possibility of miscarriages with abnormal karyotype than women with < 2 previous miscarriages (adjusted odds ratio [aOR], 0.48; 95% confidence interval [95% CI], 0.27-0.85). Although viable trisomy was observed more frequently in proportion to the increase in embryonic/fetal size at miscarriage (p_trend < 0.001), non-viable trisomy was observed more frequently in miscarriages with an embryonic/fetal size < 10 mm (aOR, 2.41; 95% CI, 1.27-4.58), but less frequently in miscarriages with an embryonic/fetal size ≥ 20 mm (aOR, 0.01; 95% CI, 0.00-0.07) than in anembryonic miscarriages.

CONCLUSIONS

The maternal age, history of miscarriage, and embryonic/fetal size at miscarriage may be independently associated with the frequencies or profiles of cytogenetic abnormalities in early miscarriages.

Relationship between the administration of nicardipine hydrochloride and the development of delirium in patients on mechanical ventilation

A history of hypertension is a known risk factor for delirium in patients in intensive care units, but the effect of antihypertensive agents on delirium development is unclear. Nicardipine, a calcium channel blocker, is widely used in ICU as a treatment agent for hypertensive emergency. This study investigated the relationship between the administration of nicardipine hydrochloride and delirium development in patients under mechanical ventilation. We conducted a medical chart review of 103 patients, who were divided into two groups according to the use of nicardipine hydrochloride. The prevalence of delirium was compared with respect to factors such as age, sex, laboratory data, and medical history, by multivariate analysis. 21 patients (20.4 %) were treated with nicardipine hydrochloride in 103 patients. The treatment and non-treatment groups differed significantly in age (72 vs. 65 years) and history of high blood pressure (57% vs. 11%). Multivariate analysis revealed that patients in the treatment group developed delirium significantly less often than those in the non-treatment group (19% vs. 48%). These results suggested that treatment of high blood pressure with nicardipine hydrochloride is a possible method for preventing the development of delirium.

[STD and mother to child transmission]

Sexually transmitted disease (STD) is the disease that is spread by sexual contact, including chlamydial infection, gonorrhea, genital warts, herpes, syphilis, and infection with human immunodeficiency virus (HIV). STDs are the most common contagious diseases among young people in Japan. People with an STD may not have any symptoms and may not know they have it. Even if there are no symptoms, their health can be affected. Advanced STDs can cause severe damage to body. Often, symptoms occur only if the disease becomes more advanced. Untreated chlamydia or gonorrhea can cause pelvic inflammatory disease (PID) in women. PID is an infection of the uterus, fallopian tubes, and ovaries. It can cause infertility and ectopic pregnancy. If patient who has STD is pregnant, it can cause abortion, premature delivery and intrauterine infection.

[Clinical experience of sivelestat sodium hydrate for severe reexpansion pulmonary edema; report of a case]

An 81-year-old man was referred to our hospital for the treatment for left spontaneous pneumothorax. A chest X-ray revealed a left-sided total pneumothorax and complete collapse of the lung. After intravenous administration of methylprednisolone, a 16 Fr chest tube was inserted, and drainage was started without negative pressure suction. Four hours after chest tube insertion, the patient's condition deteriorated. He complained severe cough and dyspnea, and pulse oximetry reading was 70%. A repeat chest X-ray demonstrated diffuse reexpansion pulmonary edema (RPE) on the left. After mechanical ventilation and intravenous infusion therapy with sivelestat sodium hydrate, methylprednisolone and ulinastatin were started, P(O2)/ Fi(O2) ratio improved rapidly. He was extubated on hospital day 6 and was discharged after pleurodesis for the pneumothorax. This case suggests that sivelestat sodium hydrate may be useful for the treatment for RPE.

Anti-phosphatidylserine-prothorombin antibody in patients with recurrent abortion and preeclampsia

AIM

The aim of the study was to describe the frequency of anti-phosphatidylserine-prothrombin antibody(aPS/PTAb) in patients with recurrent abortion and preeclampsia, and to study the relationship between the presence of aPS/PTAb and clinical finding. Eighty six cases of recurrent abortion and 82 cases of preeclampsia were studied. A aPS/PTAb was measured by an enzyme linked immunosorbent assay (ELISA).

RESULTS

In patients with recurrent abortion, 3 out of 86 cases(3.4%) were positive in IgG antibody measurements and 5 out of 86(5.8%) were positive in IgM antibody measurements. In patients with preeclampsia, 2 out of 82 cases(2.5%) were positive in IgG antibody measurements and 13 out of 82(16%) were positive in IgM antibody measurements. The positive rates of aPS/PTAb in severe hypertension-positive cases is greater than in hypertension-negative cases(p=0.045). The positive rates of aPS/PTAb is higher tendency with in severe type than in mild type(p=0.117). The positive rates of aPS/PTAb is higher tendency with proteinuria and/or hypertension than without proteinuria(p=0.098) or hypertension(p=0.096).

CONCLUSION

We found that aPS/PTAb appears in some cases of patients with recurrent abortion and preeclampsia. Our data suggest that aPS/PTAb might be a risk factor in patients with recurrent abortion, and may relate to clinical finding in preeclampsia.

[The establishment of the styles of video-assisted thoracoscopic surgery for spontaneous pneumothorax]

Video-assisted thoracoscopic surgery (VATS) has been widely used in the treatment of a pneumothorax, but the high incidence of recurrence from spontaneous pneumothorax after VATS is an important problem. In this study, we classified the groups into two categories from the thoracoscopic observations, and discussed whether or not there was reappearance of pneumothorax. In addition, we examined whether adjunctive procedure contributes to recurrent of pneumothorax after operation or not. We concluded that there is a tendency to recurrence in the group with multiple and skip lesions in the lung, and then concluded that the cases apical covering with absorbable material sheet and the use of fibrin glue spray was thought to be effective of recurrence of pneumothorax in cases of multiple and skip lesions from the intraoperative findings through the thoracoscopes. Finally, we examined application of Foley catheter for spontaneous pneumothorax under VATS. It is possible that the application of Foley catheter to prevention against recurrence of pneumothorax is a valid method.

[Practical use of taxol-based chemotherapy for poor compliance gynecologic cancers in Japanese woman]

Today, the first line of chemotherapy for ovarian cancer is Taxol-carboplatin (T-J), but there are some problems including severe bone marrow depression and severe neuropathy, so-called poor compliance cases. By changing the method of administering Taxol, the key drug in chemotherapy for ovarian cancer, it is possible to make compliance more better, continue therapies and look after patients' PS and QOL. We have considered weekly Taxol based chemotherapy for early stage recurrence cases and poor compliance cases; For example, weekly Taxol in combination with carboplatin (monthly) for poor compliance cases, severe bone marrow depression and the like, and Taxol by drip infusion for 24 hours in cases of peripheral nerve disorder (severe neuropathy). Especially, weekly Taxol combination with carboplatin (monthly), with takes advantage of the repeated administration of Taxol and one time administration of carboplatin, is a highly beneficial therapy for ovarian cancer. With this protocol we can reduce side effects and continue long-term administration on an outpatient basis.

Hypothermic neuroprotection of peripheral nerve of rats from ischemia-reperfusion injury: intraischemic vs. reperfusion hypothermia

The pathophysiology of ischemic fiber degeneration (IFD) is not known, but mechanisms involved during nerve ischemia differ from those during reperfusion. We have previously demonstrated hypothermic neuroprotection of peripheral nerve from IFD. We now evaluate the efficacy of hypothermia in the intraischemic vs. the reperfusion period, using our established model of ischemia-reperfusion injury. Intraischemic hypothermia resulted in significant recovery of all indices (behavior score, electrophysiology and histology, P<0.01 or 0.05) while hypothermia during reperfusion period showed less improvement, significant only for the histological score compared to normothermia group (IFD index, P<0.05). Once hypothermia was applied in the ischemic period, the resultant neuroprotection continued into the reperfusion period, even if nerve temperature was then raised during the reperfusion period. These results indicate that hypothermic neuroprotection is more efficacious during the intraischemic period than during reperfusion, when a lesser degree of neuroprotection ensued.

Alpha-lipoic acid provides neuroprotection from ischemia-reperfusion injury of peripheral nerve

BACKGROUND

Reperfusion aggravates nerve ischemic fiber degeneration, likely by the generation of reduced oxygen species. We therefore evaluated if racemic alpha-lipoic acid (LA), a potent antioxidant, will protect peripheral nerve from reperfusion injury, using our established model of ischemia-reperfusion injury.

METHODS

We used male SD rats, 300+/-5 g. Ischemia was produced by the ligature of each of the supplying arteries to the sciatic-tibial nerve of the right hind-limb for predetermined periods of time (either 3 or 5 h), followed by the release of the ligatures, resulting in reperfusion. LA was given intraperitoneally daily for 3 days for both pre- and post-surgery. Animals received either LA, 100 mg/kg/day, or the same volume of saline intraperitoneally. Clinical behavioral score and electrophysiology of motor and sensory nerves were obtained at 1 week after ischemia-reperfusion. After electrophysiological examination, the sciatic-tibial nerve was fixed in situ and embedded in epon. We evaluated for ischemic fiber degeneration (IFD) and edema, as we described previously.

RESULTS

Distal sensory conduction (amplitude of sensory action potential and sensory conduction velocity (SCV) of digital nerve) was significantly improved in the 3-h ischemia group, treated with LA (P<0.05). LA also improved IFD of the mid tibial nerve (P=0.0522). LA failed to show favorable effects if the duration of ischemia was longer (5-h ischemia).

CONCLUSION

These results suggest that alpha-lipoic acid is efficacious for moderate ischemia-reperfusion, especially on distal sensory nerves.

[The effects of high-dose steroid therapy on sudden deafness]

The effect of high-dose steroid therapy on sudden deafness were investigated in 19 cases. A daily intravenous administration dose of hydrocortisone sodium succinate was tapered from 800 mg to 200 mg as follows; 800 mg 800 mg, 600 mg, 600 mg, 400 mg, 400 mg, 300 mg, and 200 mg. Another 19 cases, the control group, were treated with intravenous application of prednisolone, tapered from 50 mg to 10 mg in 10-mg steps and each dose applied for 3 days. There were no significant differences in the effect on hearing between the two groups as measured by three different analyses: criteria proposed by the Committee on Sudden Deafness of the Japan Health Ministry; magnitudes of improvement of mean thresholds at five frequencies from 250 Hz to 4 kHz in affected side; and the ratio of the magnitudes of improvement of mean thresholds in affected side to magnitudes of difference between the initial mean thresholds in affected side and those in contralateral side. These findings suggest that high-dose steroid therapy for sudden deafness is not so effective as it is for idiopathic facial palsy. This may be due to the difference in the mechanisms of development between the two conditions. No critical side effects were observed in our study, which would argue for the safety of our method of high-dose steroid therapy for routine clinical use. It might be advisable to conduct additional clinical studies to determine the effect of high-dose steroid therapy for sudden deafness, because our study was conducted on a small number of patients and was not double-blind or randomized.

[Relationship between aging and morphological bone changes of the condyle in temporomandibular disorders]

In order to clarify the clinical significance of morphological bone changes of the mandibular condyle in temporomandibular disorders, the relationship between radiographic bone changes and aging was clinically studied. The subjects of the study were 1,120 patients (812 females and 308 males). The average age was 33 years +/- 15 years (from 10 to 81 years of age). The 1,120 patients were divided into six age brackets (10 to 19 years, 20 to 29 years, 30 to 39 years, 40 to 49 years, 50 to 59 years, 60 to 81 years). According to radiograms taken by lateral oblique transcranial projection, orbitcondyle projection and orthopantomography, the morphological bone changes were classified into seven groups, erosion, osteophyte, eburnation, flattening, deformity, concavity and sclerosis. The results were as follows: 1. The incidence of the patients with radiographic bone changes of the mandibular condyle increased with aging and showed significantly different age distribution from that without bone changes (Mann-Whitney U test: p < 0.01). 2. The incidence of erosion did not increase with aging and showed significantly different age distribution from osteophyte or eburnation (Mann-Whitney U test: p < 0.01, 0.05). The incidence of flattening also did not increase with aging and showed significantly different age distribution from osteophyte, eburnation or deformity (Mann-Whitney U test: p < 0.01, 0.05, 0.05).

Familial case of keratoconus with corneal granular dystrophy

A family with keratoconus combined with corneal granular dystrophy is reported. The patients are a mother and her two sons. The mother and her elder son have both keratoconus and corneal granular dystrophy; the younger son has keratoconus. Thus, the keratoconus in this family is thought to be of autosomal dominant inheritance. These familial cases suggest that the gene loci for both diseases localize in proximity or have a close relationship.

Comparison of electrophysiologic and autonomic tests in sensory diabetic neuropathy

We examined autonomic function in 46 patients with symmetric sensory non-insulin dependent diabetic neuropathy without autonomic symptoms and 31 age-matched control patients using the composite autonomic scoring scale (CASS) and electrophysiologic examination. The patients were divided into three groups by subjective severity of pain or numbness; 17 had slight pain or numbness, 15 had mild pain or numbness, and 14 had moderate pain or numbness. The patients in the moderate group had the following: a mild reduction in systolic and mean blood pressure (BP) within 1 minute of head-up tilt and a partial recovery after 5 minutes; an excessive fall in early phase II (IIe), an absence of late phase II (IIl) and reduced phase IV beat-to-beat BP responses to Valsalva maneuver (VM); a poor heart rate response to deep breathing; a reduced quantitative sudomotor axon reflex test (QSART) response in distal leg and foot; the highest CASS among the 3 groups; and reduced conduction velocity and amplitude in post-tibial nerve and sural nerve. The mild group had a mild reduction in BP during phase IIe and an absent phase IIl but normal phase IV overshoot during VM; a reduced QSART in the foot; a CASS between the moderate and slight groups; and reduced conduction velocity and amplitude in post-tibial nerve and reduced amplitude in sural nerve. The slight pain group had no abnormalities except for mild cardiovagal dysfunction. CASS gathered from all cases had a significant correlation with amplitude of sural nerve. These results suggest that the patients with symmetric sensory diabetic neuropathy may also have autonomic dysfunction, although they did not have any obvious autonomic symptoms, and that abnormalities in autonomic function parallel changes in somatic function in peripheral nerve. The CASS may be a sensitive tool, similar to the neurophysiologic test, for assessing diabetic neuropathy.

A novel 66-kDa stress protein, p66, associated with the process of cyst formation of Physarum polycephalum is a Physarum homologue of a yeast actin-interacting protein, AIP1

When exposed to various stresses including heat shock, myxoamoebae, growing haploid cells of Physarum polycephalum, show marked morphological changes and consequently become disk-shaped microcysts. We have found that p66 is induced exclusively in the course of microcyst formation and has an actin-binding activity. In this study, we purified p66 to homogeneity and isolated a p66 cDNA. The deduced protein sequence contained 601 amino acids and showed 31% identity to a yeast actin-interacting protein, AIP1. Northern blot analysis revealed that the amount of p66 mRNA was significantly increased by heat shock in myxoamoebae but not in plasmodia. Thus, p66 seems to be a developmentally-expressed stress protein which regulates the rearrangement of actin organization during microcyst formation in P. polycephalum.

[The serum zinc level in patients with tinnitus and the effect of zinc treatment]

We measured the serum zinc level in patients with tinnitus and evaluated the effectiveness of zinc in the treatment of tinnitus. Blood zinc levels were measured in 121 patients with tinnitus. All patients were examined between 1995 and 1997 at the outpatient clinic of otorhinolaryngology St. Marianna University Toyoko Hospital. Forty-seven patients who had received any drug such as a calcium channel blocker and others or had been affected by any diseases were excluded and therefore 74 patients consisting of 46 females (62%) and 28 males (38%) were investigated. Twenty two healthy volunteers served as a control group. The mean age and standard deviations for the tinnitus group and the control group were 47.8 +/- 17.1 and 31.4 +/- 8.2 years, respectively. There was a significant decrease (p < 0.0001) in serum zinc levels in patients with tinnitus compared with the control group. Because there was a significant difference (p < 0.0001) in age distribution between tinnitus and control groups, patients were selected by their age in order to neglect the effect of aging. In this situation, a significant difference (p < 0.01) was noted between the tinnitus group and control group. Low blood zinc level was defined by using the mean and standard deviation for the control group (mean-1 S.D.). We treated patients with low blood zinc levels. A total dose of 34-68 mg of Zn++ was administered daily for over 2 weeks. The degree of tinnitus was expressed on a numeric scale from 0 to 10 before and after treatment. Blood zinc levels were significantly elevated (p < 0.05) after treatment. We found a significant decrease (p < 0.01) in the numeric scale. These findings suggest that zinc is useful in at least some patients suffering from tinnitus. It is possible to classify patients with tinnitus by measuring serum zinc level and this leads to improvement of the overall treatment effect.

Promotional effects of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) on N-nitrosobis(2-oxopropyl)amine (BOP)-initiated carcinogenesis in hamsters

The effects of administration of low doses of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), a tobacco-specific nitrosamine, were investigated in hamsters treated with N-nitrosobis(2-oxopropyl)amine (BOP). Female Syrian golden hamsters were given a single sc injection of BOP at a dose of 10 mg/kg and then administered 2 or 5 ppm NNAL in their drinking water for 52 wk. Additional groups of animals received the BOP injection alone, or only the 2 or 5 ppm NNAL treatments as BOP-negative controls. At wk 53 of the experiment, all surviving animals were killed and the development of proliferative lesions was assessed histopathologically. The total incidence of combined carcinomatous and dysplastic lesions of the exocrine pancreas was significantly higher (P < 0.05) in the BOP/NNAL 5 ppm group than in the BOP alone group, although there was no statistically significant influence of NNAL on the development of either pancreatic adenocarcinomas or dysplastic lesions viewed singly. The treatments with NNAL alone did not induce any proliferative lesions of the exocrine pancreas. No significant intergroup differences were found in either incidence or multiplicity of islet cell proliferative lesions. Immunohistochemical examination of islet cell proliferative lesions (hyperplasias and adenomas) found in the BOP-treated animals showed no significant differences in pancreatic hormone production between NNAL-treated and -untreated groups. The NNAL treatment did not exert any influence on lung, liver or kidney tumorigenesis. Thus, the results suggest that NNAL enhances BOP-induced exocrine but not endocrine pancreatic tumorigenesis in hamsters when given in the post-initiation phase.

Activation of a Ca(2+)-dependent protein kinase in response in heat shock in the myxoamoebae of a true slime mold, Physarum polycephalum

Protein kinase activities in myxoamoebae of a true slime mold, Physarum polycephalum, were investigated in response to heat shock. In-gel assay detected an apparent activation of a Ca(2+)-dependent, 53-kDa protein kinase that phosphorylated casein but not histone H1. This enzyme needed co-presence of Mg2+ ion with Ca2+ for activity. Treatment with calf intestinal alkaline phosphatase did not affect the heat-inducible 53-kDa protein kinase activity at all. The effects of protein kinase inhibitors were examined, and staurosporine suppressed the activity of this enzyme completely. H-7 decreased the activity to about 20% and HA-1004 to 65%. These results suggest that this protein kinase that may phosphorylate tyrosine and serine/threonine residues of target proteins is activated by heat shock in Physarum cells, and the activation is not regulated via phosphorylation by putative protein kinase(s) that may act at an upstream position in the signaling cascade(s).

[A familial case of keratoconus with corneal granular dystrophy]

We report a familial case of keratoconus with corneal granular dystrophy. The mother and first son have both keratoconus and corneal granular dystrophy and the second son has keratoconus alone. The keratoconus in this family is thought to be an autosomal dominant or an X-linked inheritance pattern. Granular dystrophy is an autosomal dominant inheritance. This familial case suggests that the gene loci of the two diseases are close together or have a close relationship.

Long-term toxicity/carcinogenicity study of L-histidine monohydrochloride in F344 rats

The long-term toxicity and carcinogenicity of histidine, an essential amino acid for most animal species, were examined in Fischer 344 (F344) rats. Groups of 50 males and 50 females were given L-histidine monohydrochloride (HMHC) in their diet at concentrations of 0 (control), 1.25 and 2.5% for 104 wk; these dose levels were selected on the basis of the results of a subchronic toxicity study, in which body weights were depressed and formation of sperm granulomas in the epididymis was histologically evident in males fed 5.0% HMHC. All surviving rats were killed at wk 107. Increases in red blood cell count, haemoglobin value and haematocrit level were observed in male rats given 2.5% HMHC. A variety of tumours developed in all groups, including the control group, but all the neoplastic lesions were histologically similar to those known to occur spontaneously in this strain of rats, and no statistically significant increase in the incidence of any tumor was found in the treated groups of either sex. Thus, it was concluded that, under the present experimental conditions, HMHC is not carcinogenic in F344 rats.

Calcium compartments in vascular smooth muscle cells as detected by aequorin signal

1. To examine whether cytosolic Ca2+ in smooth muscle cells distributes evenly, cytosolic Ca2+ levels were measured with two different Ca2+ indicators in the ferret isolated portal vein; a fluorescent indicator, fura-PE3, that shows the average Ca2+ level, and a photoprotein, aequorin, that preferentially shows a high Ca2+ compartment. 2. A noradrenaline (10 microM)-induced sustained contraction was associated with a sustained increase in the fura-PE3 signal, or a transient increase followed by small sustained increase in the aequorin signal. A high K(+)-induced contraction was associated with a sustained increase in both the fura-PE3 and aequorin signals. 3. A second application of noradrenaline or high K+ induced reproducible contractions and fura-PE3 signals. In contrast, the aequorin signal resulting from a second application of noradrenaline or high K+ was much smaller than the first signal. 4. Following a 13 h but not a 3 h resting period, the aequorin signal stimulated by noradrenaline or high K+ recovered, without any change in the contractile response. 5. In Ca(2+)-free solution, high K+ was ineffective, whereas noradrenaline induced only a small aequorin signal and contraction compared to those obtained in the presence of external Ca2+. After the addition of Ca2+, the first application of noradrenaline induced a large aequorin signal and a large contraction, although a second application induced a much smaller aequorin signal accompanied by a large contraction. 6. These results suggest that high K+ and noradrenaline increase Ca2+ in at least two cytosolic compartments; a compartment that is coupled to the contractile mechanism ('contractile' Ca2+ compartment; major portion of cytoplasm containing contractile elements) and a compartment that is not coupled to contractile mechanisms ('non-contractile' Ca2+ compartment; small sub-membrane area that does not contain contractile elements). On stimulation, the Ca2+ level in the 'contractile' compartment may increase to a level high enough to stimulate myosin light chain kinase but not so high as to consume aequorin rapidly. In contrast, the Ca2+ level in the 'non-contractile' compartment may increase so greatly that aequorin in this compartment is rapidly consumed. These two compartments may be separated by a diffusion barrier and, during a resting period, aequorin may slowly diffuse from the 'contractile' compartment to the 'non-contractile' compartment and thus restore the full aequorin signal. An increase in Ca2+ in the 'non-contractile' compartment seems to be dependent mainly on Ca2+ influx and partly on Ca2+ release.

Dose-dependent promotion effects of potassium chloride on glandular stomach carcinogenesis in rats after initiation with N-methyl-N'-nitro-N-nitrosoguanidine and the synergistic influence with sodium chloride

The modifying effects of potassium chloride (KCl) ingestion on glandular stomach carcinogenesis were investigated in male Wistar rats induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and were compared with those of sodium chloride (NaCl). A total of 120 male 6-week-old Wistar rats were divided into six groups, each consisting of 20 animals. After initiation of treatment with a MNNG solution (100 parts/million) as their drinking water for 10 weeks, rats were fed a diet supplemented with 5% NaCl, 2.5% NaCl, 2.5% NaCl plus 2.5% KCl, 5% KCl, 2.5% KCl, or a basal diet alone for the following 62 weeks. Under this experimental condition, there were no statistical differences in the final body weights between groups. The incidences of adenocarcinomas in the glandular stomachs were significantly higher in the 5% NaCl and combined 2.5% NaCl-plus-2.5% KCl groups (P < 0.05 and 0.01) than in the MNNG alone (control) group. The incidences of atypical or precancerous hyperplasias in the glandular stomachs were increased significantly by the 5% NaCl, 2.5% NaCl-plus-2.5% KCl, and 5% KCl treatments (P < 0.05 or 0.01). The multiplicities of adenocarcinomas were significantly greater in the 5% NaCl, 2.5% NaCl, and combined NaCl-plus-KCl groups (P < 0.05 or 0.01) compared with the control value. The multiplicity data for atypical hyperplasias were most striking; namely, their multiplicities were increased significantly by the treatments of NaCl or KCl (P , 0.01) in a clear dose-dependent manner and enhanced synergistically by the combined treatment of NaCl and KCl. Because the concentrations of KCl used in this study were about 1.3 times lower than those of NaCl on a molar basis, although the doses of each chemical were exactly the same on a weight-percent basis, it is suggested that the enhancing effects of KCl might not be much different from those of NaCl. The results in the present study thus indicate that, similarly to NaCl, KCl ingestion exerts dose-dependent promoting effects and a synergistic influence with NaCl when given during the postinitiation phase of two-stage glandular stomach carcinogenesis in rats.

Inhibitory effect of forskolin on myosin phosphorylation-dependent and independent contractions in bovine tracheal smooth muscle

In bovine tracheal smooth muscle, carbachol (CCh, 1 microM) and high K+ (72.7 mM) induced sustained increases in cytosolic Ca2+ level ([Ca2+]i), myosin light chain (MLC) phosphorylation and force of contraction. Forskolin (FK, 1-10 microM) inhibited the CCh-induced increase in [Ca2+]i, MLC phosphorylation and force in parallel. In contrast, FK inhibited the high K(+)-induced contraction and MLC phosphorylation without changing [Ca2+]i. In the absence of extracellular Ca2+ (with 0.5 mM EGTA), CCh (10 microM) and caffeine (20 mM) induced transient increase in [Ca2+]i and contractile force by releasing Ca2+ from cellular store. FK strongly inhibited the CCh-induced Ca2+ transient, but failed to inhibit the caffeine-induced Ca2+ transient. In the absence of external Ca2+, 12-deoxyphorbol 13-isobutylate (DPB, 1 microM) induced sustained contraction without increase in [Ca2+]i and MLC phosphorylation. FK inhibited this contraction without changing [Ca2+]i. In permeabilized muscle, Ca2+ induced contraction in a concentration-dependent manner. FK (10 microM) and cAMP (1-100 microM) shifted the Ca(2+)-force curve to the higher Ca2+ levels. CCh with GTP, GTP gamma S or DPB enhanced contraction in the presence of constant level of Ca2+. Forskolin and cAMP also inhibited the enhanced contractions in the permeabilized muscle. In the permeabilized, thiophosphorylated muscle, ATP induced contraction in the absence of Ca2+. cAMP (300 microM) had no effect on this contraction. These results suggest that forskolin inhibits agonist-induced contraction in tracheal smooth muscle by multiple mechanisms of action; 1) inhibition of MLC phosphorylation by reducing Ca2+ influx and Ca2+ release, 2) inhibition of MLC phosphorylation by changing the MLC kinase/phosphatase balance, and 3) inhibition of regulatory mechanism which is not dependent on MLC phosphorylation.

Effects of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) on N-nitrosobis(2-oxopropyl)amine (BOP)-initiated carcinogenesis in hamsters

The effects of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) administration during the post-initiation phase of carcinogenesis were investigated in hamsters treated with N-nitrosobis(2-oxopropyl)amine (BOP). Female Syrian golden hamsters were given a single s.c. injection of BOP at a dose of 10 mg/kg and then administered 3 ppm (H) or 1 ppm (L) NNK in their drinking water for the following 87 weeks. Additional groups of animals received the BOP injection alone, or only the 3 or 1 ppm NNK treatments as BOP-negative controls. At week 88 of the experiment, all surviving animals were sacrificed and development of proliferative lesions was assessed histopathologically. The results showed no statistically significant influence on pancreatic adenocarcinomas or dysplastic lesions, although the incidence and the number of atypical hyperplasias in the pancreas head in the BOP/NNK (L) group was significantly increased as compared to BOP alone group values (P < 0.05). Similarly, the NNK treatments did not affect the incidences or multiplicities of neoplastic or hyperplastic lesions in the endocrine pancreas, lung, liver or kidney. Thus, the present experiment demonstrates that the tobacco-specific carcinogen NNK does not enhance BOP-induced hamster tumorigenesis when given in the promotion phase.

Enhancing effects of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) on cell proliferation and lipid peroxidation in the rat gastric mucosa

The influence of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone, a mutagen in chlorinated water, on cell proliferation and lipid peroxidation in the glandular stomach mucosa was investigated in male 4-week-old Wistar rats. Animals were given 50 p.p.m., 25 p.p.m., 12.5 p.p.m., 6.25 p.p.m. or 0 p.p.m. of MX solution in their drinking water for 5 weeks. At the end of this period, cell proliferation in the mucosal epithelia of the gastric fundus was increased in a dose-dependent manner up to 25 p.p.m., at which dose the induction was statistically significant as compared with the control value (P < 0.05). The MX treatment was also associated with increased lipid peroxidation levels in the gastric mucosa as well as in the urine, with loose dose-dependence, although not at 50 p.p.m. Mucosal lipid peroxidation was significantly increased in animals given 25 p.p.m. as compared with controls (P < 0.05). Similarly, the levels of urinary lipid peroxidation were significantly higher in rats given 25 p.p.m. or 12.5 p.p.m. than in the controls (P < 0.05). Histopathologically, gastric erosion was noted in rats receiving 25 p.p.m. or more of MX. There were no statistical differences between groups for serum biochemical data. The results thus suggest that MX may exert a gastric tumor-promoting action in rats, even at low doses which do not give rise to toxic effects, because of the clear dose-response relationship evident at low levels.

Carcinogenicity study of 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane in B6C3F1 mice

1,1-Bis(tert-butylperoxy)-3.3.5-trimethylcyclohexane (BBTC) is widely used in the manufacture of rubber. The present carcinogenicity study in B6C3F1 mice was carried out in order to assess its potential to induce tumours. BBTC was administered at dietary levels of 0 (control), 0.25 and 0.5% for 78 wk; these dose levels were selected on the basis of a subchronic toxicity study, in which body weights were depressed to less than 90% of the control group values and swelling of hepatocytes was histologically evident in animals fed 1% BBTC or more in the diet. Neoplasms were found in all groups, including the control group, but there were no significant differences between groups of either sex in mortality, tumour incidences or tumour distribution. All tumours were considered to be spontaneous because of the similarity to background data for B6C3F1 mice. This study thus provides no evidence of carcinogenicity of BBTC in B6C3F1 mice.

Changes in the cytoskeletal structure of cultured smooth muscle cells induced by calyculin-A

Changes in the cytoskeletal structure of cultured A10 smooth muscle cells induced by calyculin-A (CL-A), a potent inhibitor of types 1 and 2A protein phosphatases, were analyzed using indirect fluorescence techniques. In the presence of 1 × 10(−7) M CL-A the cells became round and subsequently detached from the substratum. The effect of CL-A was inhibited by a non-selective kinase inhibitor, K-252a, but not by EGTA. In rounded cells stress fibers were absent and staining for F-actin appeared in patches. Vinculin, one of the components of focal contacts, was localized at the periphery of control cells. CL-A treatment moved the focal contacts towards the inside of the cell along the stress fibers, and this was followed by the rounding up of the cell. In addition, rapid and marked changes in microtubule structure were observed in CL-A-treated cells. Many ‘nicks’ or ‘gaps’ were observed along the microtubules in the attached, spread cells. A filamentous network of microtubules was not observed in the detached cells, i.e. after longer exposure to CL-A. These results suggest that CL-A may change the structure of focal contacts, resulting in the rounding up of the cell, and inducing a microtubule-severing activity. These effects were independent of the external Ca2+ concentration. The changes in cytoskeletal structure may be caused by disturbing the balance of phosphorylation and dephosphorylation in the cell.

Contractile and relaxant effects of phorbol ester in the intestinal smooth muscle of guinea-pig taenia caeci

1. Effects of phorbol esters on the cytosolic Ca2+ level ([Ca2+]i) and muscle tension in the intestinal smooth muscle of guinea-pig taenia caeci were examined. 2. 12-Deoxyphorbol 13-isobutyrate (DPB, 1 microM) did not change the [Ca2+]i and tension in resting muscle. 3. In high K(+)-stimulated muscle, 1 microM DPB transiently augmented the contraction and decreased [Ca2+]i. 12-Deoxyphorbol 13-isobutyrate 20-acetate (1 microM) and phorbol 12, 13-dibutyrate (1 microM) showed similar effects to DPB whereas phorbol 12-myristate 13-acetate (1 microM) and phorbol 12, 13-didecanoate (1 microM) were ineffective. 4. DPB (1 microM) inhibited both [Ca2+]i and tension stimulated by 300 nM carbachol or 3 microM histamine. In the presence of a higher concentration of carbachol (1 microM), DPB decreased [Ca2+]i and transiently increased muscle tension. 5. In the muscle strips permeabilized with bacterial alpha-toxin, 1 microM DPB shifted the Ca(2+)-tension curve to the left. An inhibitor of protein kinase C, H-7 (30 microM), inhibited the effect of DPB. 6. DPB did not change the high K(+)-induced contraction in the muscle strips pretreated with 3 microM phorbol 12-myristate 13-acetate for 24 h. 7. These results suggest that activation of protein kinase C has dual effects; it augments contraction by increasing the Ca2+ sensitivity of the contractile elements and it inhibits contraction by decreasing [Ca2+]i.

Effects of felodipine, nifedipine and verapamil on cytosolic Ca2+ and contraction in vascular smooth muscle

The inhibitory effects of felodipine, nifedipine and verapamil were compared in vascular smooth muscle. In rat aorta, these inhibitors attenuated the high K(+)-induced contraction with a parallel decrease in the cytosolic Ca2+ level ([Ca2+]i). Maximal inhibition was obtained with 10 nM felodipine, 100 nM nifedipine and 10 microM verapamil. The inhibitory effects were antagonized by an increase in external Ca2+ concentration to 6.5 mM and the addition of a Ca2+ channel activator, 100 nM Bay k 8644. These inhibitors also attenuated the contraction induced by norepinephrine although these effects were weaker than those on high K(+)-induced contraction. Furthermore, these inhibitors attenuated the norepinephrine-stimulated [Ca2+]i more strongly than contraction. In contrast, none of these inhibitors inhibited the transient increase in [Ca2+]i and muscle tension induced by norepinephrine in Ca(2+)-free solution and the Ca(2+)-induced contraction in permeabilized smooth muscle. These results suggest that felodipine, nifedipine and verapamil inhibit smooth muscle contraction by inhibiting Ca2+ channels at concentrations which do not change Ca2+ release or Ca2+ sensitivity of contractile elements.

Leakage of the fluorescent Ca2+ indicator fura-2 in smooth muscle

The movement of a fluorescent intracellular Ca2+ indicator, fura-2, in smooth muscle was examined. Strips of rat and rabbit aortas and bovine trachea were loaded with the acetoxymethyl ester of fura-2 (fura-2/AM), followed by washing with normal physiological solution. Not only fura-2/AM but also fura-2 was detected in the washout solution. The amount of fura-2 in the cells, measured fluorometrically, decreased gradually during the washout. The decrease was fastest in rat aorta followed by rabbit aorta > bovine trachea. In rat aorta, fura-2 leakage was inhibited by an inhibitor of anion transport, probenecid, or by a decrease in bath temperature. The Ca2+ ionophore ionomycin (10 microM) increased the leakage of fura-2, which was not inhibited by probenecid, possibly because a high concentration of ionomycin nonselectively increased membrane permeability. These results suggest that fura-2/AM is cleaved to fura-2 in the cell which gradually leaked out of the cell mainly by an anion transport system. The amount of fura-2 in the cell seemed to be determined mainly by the rate of leakage of fura-2, which is the largest in rat aorta followed by rabbit aorta and bovine trachea.

Effects of hickory smoke condensate on gastric carcinogenesis in Wistar rats after treatment with N-methyl-N'-nitro-N-nitrosoguanidine and sodium chloride

Short-term assays in vivo have suggested that hickory smoke condensate (HSC), a food flavouring, might have tumour-initiating and/or promoting activities in the glandular stomach of the rat. In the present study, the modifying effects of HSC on glandular stomach carcinogenesis after initiation with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and sodium chloride (MNNG salt) were investigated in male Wistar rats. Animals were given MNNG solution (100 ppm) as drinking water and simultaneously fed the diet supplemented with 5% sodium chloride for 8 wk. Matched negative controls received neither MNNG nor sodium chloride. Rats were then fed a basal diet and given HSC solution (1 or 3%) or tap water for the following 32 wk. During the experimental period, treatment with MNNG salt and administration of HSC both brought about growth retardation although the final body weight of rats was comparable between groups. Only two rats treated with MNNG salt followed by 1% HSC developed adenocarcinoma of the stomach. HSC treatment appeared to increase the number of rats with preneoplastic hyperplasias and/or adenocarcinomas in both the fundic and pyloric mucosa, although not to a statistically significant extent. HSC administration significantly increased malondialdehyde levels in the urine and gastric mucosa, the former in a dose-dependent manner. The results suggest that HSC has little, if any, promoting effect on two-stage glandular stomach carcinogenesis in rats when given during the post-initiation phase. However, the tumour co-initiating effects of HSC require further clarification.

The long-term inhibitory effect of a Ca2+ channel blocker, nisoldipine, on cytosolic Ca2+ and contraction in vascular smooth muscle

The mechanism of the long-term inhibitory effect of a dihydropyridine Ca2+ channel blocker, nisoldipine, on contraction and cytosolic Ca2+ level ([Ca2+]i) was examined in isolated rat aorta. Nisoldipine inhibited the [Ca2+]i and muscle tension induced by high K+. The inhibitory effects were antagonized by a Ca2+ channel activator, 100 nM Bay k8644, and by a high concentration of Ca2+ (6.5 mM). Ultraviolet light, which has been shown to decompose dihydropyridines, attenuated the effects of nisoldipine. After nisoldipine had been removed from muscle bath, the inhibitory effect faded away slowly. The residual inhibitory effects on [Ca2+]i and muscle tension were antagonized by Bay k8644, high Ca2+ and ultraviolet light. These results suggest that the inhibitory effect of nisoldipine is caused by a decrease in [Ca2+]i as a result of inhibition of L-type Ca2+ channels, and that the residual inhibitory effects are caused by the same mechanism as the inhibitory effects of nisoldipine, namely the tight binding of nisoldipine to Ca2+ channels even after washout.

Mechanism of relaxing action of the antiasthmatic drug, azelastine, in isolated porcine tracheal smooth muscle

Azelastine (1-300 microM) inhibited contractions of isolated porcine trachea induced by high K+, carbachol and endothelin-1 (ET-1) with a decrease in [Ca2+]cyt (as measured by fura-2-fluorescence). Verapamil (0.1-10 microM) also inhibited the high K(+)-induced increases in [Ca2+]cyt and contraction, although it only partially inhibited the responses evoked by carbachol or ET-1. In the absence of extracellular Ca2+ (with 0.5 mM EGTA), carbachol induced a transient increase in [Ca2+]cyt and force by releasing Ca2+ from cellular stores. Azelastine (100 microns) completely inhibited these contransient changes. In the absence of extracellular Ca2+, carbachol and 12-deoxyphorbol 13-isobutyrate (DPB) induced small sustained contractions without increasing [Ca2+]cyt. Azelastine inhibited these contractions. In muscle permeabilized with alpha-toxin, Ca2+ (0.3-3 microM) induced contraction in a concentration-dependent manner. DPB (without GTP) and carbachol or ET-1 (with GTP) enhanced the Ca(2+)-induced contraction. Azelastine partially inhibited the contraction induced by 0.3 microM Ca2+ but not the contraction induced by 3 microM Ca2+, and strongly inhibited the potentiating effects of DPB, carbachol and ET-1. Azelastine had no effect on the content of cyclic AMP or cyclic GMP. These results suggest that azelastine inhibits smooth muscle contraction by (i) decreasing [Ca2+]cyt, by inhibition of Ca2+ channels, (ii) decreasing agonist-induced Ca2+ release, and (iii) direct inhibition of contractile elements.

Inhibitory effects of crude soybean trypsin inhibitor on pancreatic ductal carcinogenesis in hamsters after initiation with N-nitrosobis(2-oxopropyl)amine

The effects of soybean trypsin inhibitor (SBTI) administration during the promotion phase of pancreatic carcinogenesis were investigated. Female Syrian golden hamsters were given three weekly s.c. injections of N-nitrosobis(2-oxopropyl)amine (BOP) each at a dose of 10 mg/kg and then administered 5% SBTI diet for the following 37 weeks. Additional groups of animals received the BOP injection alone or the 5% SBTI diet alone as controls. At week 40 of the experiment, all surviving animals were killed and development of pancreatic lesions was assessed histopathologically. The results showed that the incidence of dysplastic lesions in hamsters of the BOP/SBTI group was significantly decreased as compared to that of the BOP group (P < 0.01). A similar but not significant tendency was also found for pancreatic adenocarcinomas. In addition, the number of dysplastic lesions in the pancreas head portion in the BOP/SBTI group were significantly decreased as compared to the BOP group value (P < 0.05). Furthermore, atrophic changes of the pancreatic exocrine tissue were more severe in the BOP group than in the BOP/SBTI group (P < 0.01), indicating that SBTI treatment gave effective protection against the replacement process of acinar cell induced by BOP. Thus, the present experiment demonstrated that SBTI can inhibit hamster pancreatic ductal carcinogenesis when given in the promotion phase, in clear contrast to the enhancing effects reported for preneoplastic acinar lesion development in rats.

Inhibitory effect of calcium chloride on gastric carcinogenesis in rats after treatment with N-methyl-N'-nitro-N-nitrosoguanidine and sodium chloride

The effects of calcium chloride on glandular stomach carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and sodium chloride were investigated in male outbred Wistar rats. Animals were given MNNG solution (100 p.p.m.) as drinking water and simultaneously fed a diet supplemented with 5% sodium chloride for 8 weeks. Matched negative controls received neither MNNG nor sodium chloride. Rats were then fed basal diet and given calcium chloride solution (1 or 0.2%) or tap water for the following 52 weeks. The incidences and multiplicities of preneoplastic hyperplasias in the glandular stomachs of rats given MNNG/sodium chloride followed by 1 and 0.2% calcium chloride were significantly lower than those in rats given MNNG/sodium chloride alone. The inhibitory effects of calcium were exerted in a dose-dependent manner. Calcium treatment also showed a tendency to inhibit the development of gastric adenocarcinomas although this was not statistically significant. Rats without carcinogen treatment had neither carcinomas nor preneoplastic hyperplasias in the glandular stomach. Calcium intake also significantly reduced the levels of malondialdehyde, a measure of lipid peroxidation, in the gastric mucosa and urine, the former in a dose-dependent manner. Thus, calcium chloride exerted inhibitory effects when given during the post-initiation phase of two-stage glandular stomach carcinogenesis in rats.

[Biopsy of head and neck lesions with a Biopty biopsy instrument]

Recently, "Biopty-Gun" technique has been introduced as a new biopsy technique specially in urological field. We applied it to obtain histopathological specimens of head and neck lesions. 25 specimens were taken with 18-gauge needle, using ultrasonic guidance in cases where the targets were very close to arteries or very small or cystic lesions. All these 25 specimens could be obtained without any complication such as crushing of tissue and they were all sufficiently clear and high-quality specimens. In 23 of these 25 specimens, exact histopathological diagnosis could be made. "Biopty-Gun" minimizing possible movement of tissue which may often occur with the conventional biopsy technique, permitted obtaining tissue specimens without crushing or damaging cells of tissue to be sampled, and it was concluded to be a highly safe and useful biopsy procedure.

[13-week subchronic toxicity study of 1,1-bis(t-butylperoxy) 3,3,5-trimethyl cyclohexane in mice]

A 13-week subchronic toxicity study of 1,1-bis(t-butylperoxy)3,3,5-trimethyl cyclohexane (TMCH) was performed in male and female B6C3F1 mice by feeding a CRF-1 powder diet containing 0, 0.5, 1.0, 2.0 and 4.0% TMCH, to determine the maximum tolerable dose (MTD) for subsequent carcinogenicity study. Mice were randomly divided into 5 groups, each consisting of 10 males and 10 females. Eight animals of both sexes in the 4.0% TMCH group died during the early administration period. Suppression of body weight gains was marked in both sexes of the 4.0% and 2.0% TMCH groups as compared with the control group. The mean food consumption in all groups treated with TMCH was lower than that in the control group in a dose-related manner. Hematological examination revealed decreases in the number of erythrocytes, volume of hemoglobin, and values for hematocrit and mean corpuscular volume (MCV) in both sexes of the 4.0% and 2.0% TMCH groups. The relative liver weights of all groups treated with TMCH increased in a dose-related manner, whereas both absolute and relative spleen weights decreased in a dose-dependent manner. Histopathologically, swelling of the hepatocytes was found centrilobularly or diffusely in both sexes of the 1.0, 2.0 and 4.0% TMCH groups, and decrease of the hematopoietic cells in the bone marrow was observed in both sexes of the 2.0 and 4.0% TMCH groups. In addition, atrophy of red pulp and white pulp of the spleen was found in both sexes of the 2% and 4% TMCH groups.(ABSTRACT TRUNCATED AT 250 WORDS)

[Studies on cell proliferation activities in acute toxic lesions in the liver and pancreas of hamsters treated with N-nitrosobis(2-oxopropyl)amine]

Histopathology and cell proliferation activities in acute toxic lesions in the liver and pancreas of female Syrian hamsters given a S.C. injection of N-nitrosobis(2-oxopropyl)amine (BOP) at a dose of 100 mg/kg, were investigated. Histologically, at one day after administration, hypertrophy and focal necrosis of the hepatocytes were observed, whereas no remarkable changes were seen in the pancreas. At 7 days after administration, when diffuse hypertrophy, vacuolation and necrosis of the hepatocytes, and atypical hyperplasia of the bile duct were seen in the liver, hyperplasia of the pancreatic duct and focal necrosis and vacuolation of the acinar cells were noticed in the pancreas. Immunohistochemistry for both 5-bromodeoxyuridine (BrdU) and proliferating cell nuclear antigen (PCNA) revealed remarkable increases of cell proliferation activities in the target cells for BOP toxicity, especially at 7 days after BOP treatment. Meanwhile, the number per nucleus of silver-stained proteins related to nucleolar organizer regions (AgNOR) was significantly increased in the target cells at both 1 and 7 days after BOP treatment. Thus, in the present study, it was suggested that acute toxic changes in the liver of hamsters treated with BOP precedes those in the pancreas. The speculation that AgNOR may be an indicator recognizing earlier alterations on acute BOP toxicity remains to be examined.

Studies on an enzymatically synthesized antitumor polysaccharide SPR-901

An antitumor polysaccharide SPR-901 was found in a fermented broth of a kind of lactic acid bacteria isolated from rice bran. SPR-901 is a high molecular alpha-glucan and its linkages are almost linear alpha-1,6 glucosidic ones with a small amount (ca. 5%) of branches at C-3 positions. It is a highly purified alpha-glucan and it contains no protein and no inorganic salts. SPR-901 showed significant antitumor activities against murine allogeneic and syngeneic tumors by both intraperitoneal and oral administration, and enhanced carbon clearance ability in mice, while it showed no direct cytotoxicities in vitro. The mechanism of antitumor activities of SPR-901 is supposed to be a host-mediated one, and this substance is classified as one of the biological response modifiers. These properties of SPR-901 were identical to those of RON, which was obtained from rice bran, therefore we concluded that these two polysaccharides were the same substance.

Dual effects of carbachol on cytosolic Ca2+ and contraction in intestinal smooth muscle

The effects of carbachol on muscle tension and cytosolic Ca2+ concentrations ([Ca2+]cyt), measured with fura-2, were examined in the guinea pig intestinal smooth muscle. Carbachol induced an initial transient increase followed by a sustained increase in [Ca2+]cyt and muscle tension. Higher concentrations of carbachol induced larger transient changes and smaller sustained changes. In the presence of carbachol, application of Ca2+ to a Ca2(+)-depleted muscle induced a contraction that was smaller in the presence of higher concentrations of carbachol. High concentrations of carbachol inhibited the high-K(+)-stimulated muscle tension and [Ca2+]cyt. Contractile and inhibitory effects of carbachol were inhibited by a muscarinic M2 antagonist. Increase in the external Ca2+ concentration or addition of BAY K 8644, a Ca2(+)-channel activator, antagonized the inhibitory effect. There was a linear correlation between log [Ca2+]cyt and muscle tension under the conditions employed in the present experiments (r = 0.949). These results suggest that lower concentrations of carbachol increase [Ca2+]cyt and induce contraction, whereas high concentrations of carbachol have an additional effect to decrease [Ca2+]cyt and inhibit contraction by a Ca2(+)-channel blocker-like action.