Adrenomedullin-sensitive receptors are preferentially expressed in cultured rat mesangial cells

By using cultured rat mesangial cells, we compared the effects on cyclic nucleotide levels of adrenomedullin with those of the structurally related peptides, calcitonin gene-related peptide (CGRP) and amylin. Adrenomedullin potently increased cAMP levels 7-fold in a time- and concentration-dependent manner. Its EC50 was 3 x 10(-9) M. CGRP was less potent (2-fold) with an EC50 of 10(-7) M, and amylin had no effect on cAMP levels. All three peptides failed to increase cGMP levels. Treatment of cells with near maximal concentrations of adrenomedullin (10(-7) M) and CGRP (10(-6) M) had no additive effect on cAMP levels. Human adrenomedullin-(22-52)-NH2, a putative adrenomedullin receptor antagonist, inhibited the production of cAMP elicited by adrenomedullin (IC50: 7 x 10(-8) M) and CGRP (IC50: 5 x 10(-8) M). Human CGRP-(8-37), a CGRP receptor antagonist, conversely, reduced the cAMP elevation caused by these peptides with a lower potency (IC50: 10(-6) M for both peptides). This demonstrated that human adrenomedullin-(22-52)-NH2 was a more effective antagonist for adrenomedullin- and CGRP-specific receptors than human CGRP-(8-37). Results suggest that receptors sensitive to adrenomedullin are preferentially expressed in cultured rat mesangial cells. Immunohistochemical study showed almost no immunoreactive adrenomedullin and CGRP, if any, in the cells. Adrenomedullin may regulate mesangial function as either a paracrine or circulating hormone via a cAMP- but not a cGMP-dependent mechanism.

Microsatellite instability in sporadic human breast cancers

Human breast-cancer specimens from 100 patients were analyzed for microsatellite instability (referred to as replication error; RER) at 12 genomic loci on 7 chromosomes, and results were correlated with clinicopathologic characteristics. In 42 of 100 breast-cancer patients, we investigated whether RER was associated with the amplification of oncogenes and/or suppression of tumor-suppressor genes. Of the 100 patients, 8 (8%) were RER-positive at one or more chromosomal loci. The majority of RER-positive patients had early-stage disease with ER-positive tumors, suggesting that RER occurs early in breast tumorigenesis. However, no significant correlation was observed between RER and oncogenes or tumor-suppressor genes. Thus, the mechanism of RER in sporadic human breast cancer may be independent of the multi-step carcinogenesis caused by the alterations of oncogenes and tumor-suppressor genes.

Expression of epidermal growth factor, epidermal growth factor receptor and transforming growth factor-alpha in the human fetal inner ear

The expression of epidermal growth factor (EGF), EGF receptor and transforming growth factor (TGF)-alpha was analyzed in the human fetal inner ear using immuno-histochemical methods. EGF receptor was observed only in 9.5-week-old fetal vestibular epithelia. In 14- and 16-week-old fetuses, EGF receptor could not be detected. TGF-alpha was observed strongly in the 9- and 11-week-old vestibular epithelia, whereas only trace amounts were detectable in the 14- and 16-week-old vestibular epithelia. These findings suggest that EGF and TGF-alpha probably have a mitogenic effect in the sensory epithelia of the fetal inner ear, especially at early stages of development.

[An operative case of suture-granuloma which resulted from an intra-pulmonary treatment 10 years ago and manifested hemoptysis]

We experienced a 27-year-old male patient with recurrent hemoptysis manifested by granuloma which resulted from surgical repair that was performed for right pneumothorax using unabsorbable sutures (braided silk) before 10 years. The patient had been suffering from fever and cough for three months before hemoptysis. Chest X-ray and CT scan films showed a mass shadow in the lateral side of the right lung field. Furthermore, bronchoscopy revealed bleeding in B3 of the right lung. The patient underwent right upper lobectomy, which disclosed that hemoptysis was due to a granuloma (2.3 x 3.2 cm in size) formed around sutures. The granuloma was caused not only by foreign body reaction but also by transbronchial infection.

[Malignant paraganglioma with intracranial metastasis: a case report]

We report a case of malignant paraganglioma with intracranial metastasis. A 26-year-old man presented with leg pain. On admission a metastatic bone tumor was found. General examination revealed metastatic lesions in the lung, liver, orbits, ethmoid sinus, anterior mediastinum, and brain. An MRI of the head showed multiple lesions in the skull bone and intracranial space. A biopsy was performed on the right temporal tumor, resulting in a diagnosis of malignant paraganglioma. The tumor origin could not be determined. The tumor resection was not indicated because of multiple metastasis. Both chemotherapy and radiotherapy were given to the patient, but a satisfactory outcome was not obtained.

Proadrenomedullin N-terminal 20 peptide (PAMP) reduces inward currents and Ca2+ rises induced by nicotine in bovine adrenal medullary cells

It has been recently reported that proadrenomedullin N-terminal 20 peptide (PAMP), which is secreted with adrenomedullin and catecholamines from the adrenal medulla, inhibits catecholamine release stimulated with nicotine. In the present study, to elucidate anticholinergic mechanisms of PAMP we employed the whole-cell patch-clamp and the intracellular Ca2+ imaging techniques in cultured bovine adrenal medullary cells. PAMP inhibited nicotinic currents and [Ca2+]i rises induced by nicotine in a dose-dependent manner (10(-9)-10(6) M). These inhibitions were selective, since PAMP alone did not induce any ionic currents, moreover it did not affect voltage-dependent Ba2+ currents or high K+ (50 mM)-induced [Ca2+]i rises. The onset of the inhibitory effect of PAMP (10(-6) M) was very rapid and reached a steady-state level within 10 sec. The effect of PAMP (10(-6) M) lasted for about 10-15 min. Desensitization process of the nicotinic current fitted to a single exponential function with a time constant of 6.4 +/- 0.3 sec. When PAMP (10(-6) M) simultaneously added with nicotine (10(-5) M), the desensitization process was facilitated and fitted to two exponentials with time constants of 0.46 +/- 0.08 and 2.5 +/- 0.8 sec. From the present results, the inhibition by PAMP of nicotinic currents which was well associated with that of nicotine induced [Ca2+]i rises leads to the attenuation of catecholamine release probably, at least in part, due to the facilitation of the desensitization process of the nicotinic currents.

Relationship between the pathogenicity of the pine wood nematode, Bursaphelenchus xylophilus, and phenylacetic acid production

Phenylacetic acid (PA), a toxin produced by three strains of bacteria accompanying the pine wood nematode, Bursaphelenchus xylophilus, was found to be formed in a culture of the nematode. An animal nutrient, nutrient broth (NB) medium, was more suitable for PA production of the accompanying bacteria than a vegetable nutrient, potato sucrose malt extract (PSM) medium. It is presumed that dead nematodes in the PSM medium provided the bacteria with nutrient for PA production. In the culture of virulent isolate OKD-3, more PA was detected than in that of less-virulent isolate OKD-1. PA production of the accompanying bacteria can dominate the pathogenicity of the nematode.

Granulomatous mastitis diagnosed and followed up by fine-needle aspiration cytology, and successfully treated by corticosteroid therapy: report of a case

A 36-year-old woman presented to our hospital with a rapidly growing lump in her left breast. Fine-needle aspiration (FNA) cytology of the mass revealed many epithelioid cells admixed with multinucleated Langhans-type giant cells, neutrophils, lymphocytes, and stromal cells, leading to a diagnosis of granulomatous mastitis. This report describes the clinical course of this patient in whom granulomatous mastitis was successfully treated with corticosteroid therapy. Special reference is made to the usefulness of FNA cytology in the diagnosis and follow-up of this disease.

Giant intracranial aneurysms in two sisters: case report

BACKGROUND

It is rare for intracranial aneurysms to present with cranial nerve palsy caused by the space-occupying effect of the lesion. Herein we discuss two sisters with familial intracranial aneurysms, both of whom presented with cranial nerve palsy.

CASE DESCRIPTION

Two female siblings presented with ocular movement and facial sensory disturbances caused by the space-occupying effect of giant aneurysms at the cavernous portion of the internal carotid arteries. The aneurysms were located at the identical site in both patients. Proximal occlusion of the internal carotid artery was effective in both cases, resulting in the promotion of thrombosis within the aneurysms in order to reduce their space-occupying effect.

CONCLUSION

This is considered to be the first known case of siblings, both suffering from giant internal carotid artery aneurysms.

ASA physical status and age are not factors predicting morbidity, mortality, and survival after pancreatoduodenectomy

To evaluate the effects of age and physical status on postoperative complications, American Society of Anesthesiologists-Physical Status score (ASA score) and age were analyzed in patients undergoing pancreatoduodenectomy (PD). Medical records and follow-up results of 69 patients who had undergone PD from 1980 to 1993 at one institution were examined. Clinical variables affecting morbidity and mortality rates were analyzed, and compared between two-aged groups (> or = 70 years (n = 18) and < 70 (n = 51)). Univariate Cox regression analysis of 69 patients showed that ASA score and age were not significant factors affecting postoperative morbidity, mortality, and survival. The clinical variables including ASA score, gender, operative time, blood loss, stage, and location of carcinoma were similarly distributed between the two-aged groups. The mortality rate in patients less than 70 years of age was 5.9 per cent (3/51), whereas there was no mortality in patients more than 70 years of age. The morbidity, mortality, and cumulative survival rates were statistically similar in the two age groups. The results suggest that ASA-physical status and age are not limiting factors for PD and do not predict survival. The procedure is safe and worthwhile even in patients more than 70 years of age with the ASA score up to III.

Identification of type I and type II serine/threonine kinase receptors for growth/differentiation factor-5

Growth/differentiation factor-5 (GDF-5) is a member of the bone morphogenetic protein (BMP) family, which plays an important role in bone development in vivo. Mutations in the GDF-5 gene result in brachypodism in mice and Hunter-Thompson type chondrodysplasia in human. BMPs transduce their effects through binding to two different types of serine/threonine kinase receptors, type I and type II. However, binding abilities appear to be different among the members of the BMP family. BMP-4 binds to two different type I receptors, BMP receptors type IA (BMPR-IA) and type IB (BMPR-IB), and a type II receptor, BMP receptor type II (BMPR-II). In addition to these receptors, osteogenic protein-1 (OP-1, also known as BMP-7) binds to activin type I receptor (ActR-I) as well as activin type II receptors (ActR-II and ActR-IIB). Here we investigate the binding and signaling properties of GDF-5 through type I and type II receptors. GDF-5 induced alkaline phosphatase activity in a rat osteoprogenitor-like cell line, ROB-C26. 125I-GDF-5 bound to BMPR-IB and BMPR-II but not to BMPR-IA in ROB-C26 cells and other nontransfected cell lines. Analysis using COS-1 cells transfected with the receptor cDNAs revealed that GDF-5 bound to BMPR-IB but not to the other type I receptors when expressed alone. When COS-1 cells were transfected with type II receptor cDNAs, GDF-5 bound to ActR-II, ActR-IIB, and BMPR-II but not to transforming growth factor-beta type II receptor. In the presence of type II receptors, GDF-5 bound to different sets of type I receptors, but the binding was most efficient to BMPR-IB compared with the other type I receptors. Moreover, a transcriptional activation signal was efficiently transduced by BMPR-IB in the presence of BMPR-II or ActR-II after stimulation by GDF-5. These results suggest that BMPR-IB mediates certain signals for GDF-5 after forming the heteromeric complex with BMPR-II or ActR-II.

Orally active, nonpeptide vasopressin V2 receptor antagonists: a novel series of 1-[4-(benzoylamino)benzoyl]-2,3,4,5-tetrahydro-1H-benzazepines and related compounds

This paper describes a novel series of nonpeptide vasopressin V2 receptor antagonists. It has been demonstrated that the 1-[4-(benzoylamino)benzoyl]-2,3,4,5-1H-benzazepines and 1-[4-(benzoylamino)benzoyl]-2,3,4,5-1H-1,5-benzodiazepines show a high affinity for V2 (and V1a) receptors. Among the 1-[4-(benzoylamino)benzoyl]-2,3,4,5-1H-benzazepine series, compounds with an alkylamino group on the benzazepine ring have been shown to have oral activity. A lipophilic group at the ortho position on the terminal benzoyl ring is important for both high V2 receptor affinity and oral activity. On the basis of these favorable properties, clinical testing of 31b has begun for use as an oral and iv aquaretic agent.

Nicotine rescues PC12 cells from death induced by nerve growth factor deprivation

We examined the protective effect of nicotine against neuronal cell death in the model system of serum- and nerve growth factor (NGF)-free cultures of PC12 cells. Serum deprivation induced massive death of undifferentiated PC12 cells, which was inhibited by the addition of NGF, but not by the addition nicotine (100 microM). Even after PC12 cells had been differentiated by the treatment with NGF, serum and NGF deprivation induced rapid and massive death of these cells. The addition of nicotine (1-100 microM) to the deprivation system prevented such cell death almost completely. The protective effect of nicotine was abolished by hexamethonium or mecamylamine, inhibitors of nicotinic acetylcholine (nACh) receptors. Treatment with reserpine to deplete intracellular catecholamines did not influence the effect. The results suggest that the protective effect of nicotine against neuronal cell death is exerted through nACh receptors.

Laparoscopic splenectomy aided by balloon occlusion of the splenic artery: report of a case

Laparoscopic splenectomy often involves difficulties in patients with splenomegaly because of a poor visual field and distorted and enlarged vessels secondary to the enlarged spleen. For safe and efficient laparoscopic splenectomy, we performed balloon occlusion of the splenic artery with the interventional angiographic technique in a patient with hereditary spherocytosis and splenomegaly. This new approach may be useful in terms of safety and time savings, especially in patients with splenomegaly.

Internal representation of two-dimensional shape

The psychological space of shapes has been studied in many experiments. However, how shapes are represented in the brain has not been a major issue in psychological literature. Here, the characteristics of internal representation and how it was formed have been considered and an attempt has been made to explain the results of experiments in a unified manner. First, the data of similarity of alphabetic characters and random-dot patterns were reexamined. Multivariate analysis suggested that those patterns were represented by the combination of global features. Second, three-layer neural networks were trained to perform categorization or identity transformation of the same sets of patterns as used in psychological experiments, and activation patterns of the hidden units were analyzed. When the network learned categorization of the patterns, its internal representation was not similar to the representation suggested by psychological experiments. But a network which learned identity transformation of the patterns could acquire such an internal representation. The transformation performed by this kind of network is similar to principal-component analysis in that it projects the input image onto a lower-dimensional space. From these results it is proposed that two-dimensional shapes are represented in human brain by a process like principal-component analysis. This idea is compatible with the findings in neurophysiological studies about higher visual areas.

The temporary threshold shift of vibratory sensation induced by composite-band vibration exposure

Eight healthy subjects were exposed to three 1/3 octave-band vibrations (63, 200, and 500 Hz) by hand clasping a vibrated handle in a soundproof and thermoregulated room. The vibratory sensation threshold at 125 Hz was measured before and after the vibration exposure at an exposed fingertip. According to a preceding study, we first determined the relationship between the acceleration of the vibration and the temporary threshold shift of vibratory sensation immediately after the vibratory exposure (TTSv,0) induced by 1/3 octave-band vibration. We then measured TTSv after the exposure to a composite vibration composed of two 1/3 octave-band vibrations that might induce an equal magnitude of TTSv,0 on the basis of the above relationship. The TTSv,0 induced by the composite vibration was not larger than the TTSv,0 induced by the component vibrations. This result suggests that the component of the vibration inducing the largest TTSv,0 determines the TTSv,0 by broad-band random vibration.

[Effective mechanisms of laser photocoagulation for neovascularization in diabetic retinopathy]

Effective mechanisms of laser photocoagulation for neovascularization in diabetic retinopathy were investigated in regard to change in oxygen pressure in the retina and vitreous and cytokines related to ischemia. The mechanism of laser photocoagulation is suggested to be as follows. 1. Destruction of the outer retina, especially of photoreceptors that have high oxygen consumption decreases metabolic function of the outer retina and its oxygen consumption. 2. The destruction allows increase of oxygen diffusion from choroidal vessels to inner retina, which improves the metabolic function by equilibrating oxygen demand and supply in the inner retina. (3) Production and secretion of neovascular factors such as vascular endothelial growth factor (VEGF) is decreased by the improvement of hypoxia. 4. The neovascularization is decreased by the synergistic effect between the neovascular factors and suppressors such an VEGF, fibroblast growth factor (FGF), and transforming growth factor-beta (TGF-beta). The improvement of the retinal ischemia and the decrease of cytokines are implicated in the regression of neovascularization by the laser photocoagulation for diabetic retinopathy.

Hepatic bile acid synthesis and DNA synthetic rate after partial hepatectomy

The relationship between hepatic DNA synthetic rate and activity of cholesterol 7 alpha-hydroxylase, the rate limiting enzyme for bile acid synthesis, was examined in regenerating liver after partial hepatectomy or sham operation in rats. Hepatic cholesterol 7 alpha-hydroxylase activity was significantly (P < 0.001) suppressed on days 1 and 2, returned to the control level on day 3, and was significantly raised on day 7 after hepatectomy. The rate of DNA synthesis was significantly (P < 0.001) activated during the first 3 days after hepatectomy and returned to the control level on day 7. Enzyme activities regulating hepatic bile acid synthesis and DNA synthesis change inversely during liver regeneration after hepatectomy.

Primary B-cell lymphoma of the breast in patient with smoldering type adult T-cell lymphoma

We report a patient with primary B-cell lymphoma of the breast complicated by smoldering type adult T-cell leukaemia (ATL). A 52-year-old Japanese woman complained of a rapidly enlarging lump in her right breast. She had been diagnosed to have smoldering type ATL since the age of 49. Aspiration cytology and subsequent excisional biopsy revealed B-cell type lymphoma of the breast. A gallium-scintigram showed abnormal accumulation in the bilateral breasts. Radiology was adopted because the lesion was localized only in the breasts and associated with smoldering type ATL. The lesions disappeared after the treatment.

Bone morphogenetic protein type IB receptor is progressively expressed in malignant glioma tumours

The distribution of bone morphogenetic protein (BMP) type I receptors and the activin type I receptor (ActR-I) was investigated in 16 cases of human glioma and five cases of non-tumourous gliosis tissue by immunohistochemical technique. Both BMP type IA (BMPR-IA) and the type IB (BMPR-IB) receptors were detected in human glioma cells. A significant increase in BMPR-IB in tumour cells was observed in malignant glioma compared with both low-grade astrocytomas (n=16, P<0.005) and gliosis (n=13, P<0.001). However, enhancement of BMPR-IA staining was moderate and ActR-I staining was only weakly expressed in the malignant glioma tumours. Osteogenic protein (OP)-1/BMP-7, which is known to bind BMPR-IA, BMPR-IB and ActR-I, was expressed in nervous tissue and was also detected in anaplastic areas of malignant glioma. In contrast to the tissue materials, BMPR-IA was expressed to a stronger degree than BMPR-IB in human glioma cell lines; the growth of these cells was suppressed by OP-1. These results suggest the presence of BMP receptors and a functional role for BMPs in malignant glioma.

Expression of TGF-beta type I and type II receptors in rat eyes

Transforming growth factor beta (TGF-beta) transduces signals through mediation of type I and type II serine/threonine kinase receptors. The expression of TGF-beta type I (T beta R-I) and II (T beta R-II) receptors in rat eyes was investigated immunohistochemically. T beta R-I and T beta R-II immunoreactivity was detected in corneal and conjunctival epithelial cells, corneal endothelial cells, ciliary epithelial cells, lens epithelial cells, retinal pigment epithelial cells, and choroidal vessels. This co-expression of T beta R-I and T beta R-II indicates that the above cells respond to TGF-beta and, because TGF-beta is reported to be produced in ocular tissues, that it may have important autocrine and/or paracrine roles in the growth and metabolism of ocular tissues in situ.

Sequential changes of energy charge, lipoperoxide level, and DNA synthesis rate of the liver following biliary obstruction in rats

To clarify the effects of obstructive jaundice on the liver, sequential changes of hepatic energy charge, the concentrations of adenine nucleotides and malondialdehyde, DNA synthesis rate, and histology of the liver were examined on the day before and Days 1, 2, 4, 7, and 14 after biliary obstruction in rats and compared with those of sham-operated controls. Foci of necrotic hepatocytes were present on Days 1 and 2 and mitoses of the hepatocytes were frequently observed with a peak on Day 2 in the jaundiced liver. Marked proliferation of bile ductules were subsequently observed on Days 7 and 14, resembling biliary cirrhosis. The DNA synthesis rate was significantly activated after bile duct obstruction with its peak on Day 2, more than nine times higher than the control value and returned to the control level on Day 14. Hepatic ATP concentration and energy charge gradually declined with prolonged jaundice and significantly lower levels persisted after Day 7 compared with the controls. The malondialdehyde level in the jaundiced liver gradually increased and became significantly higher on Day 14. We conclude that obstructive jaundice decreases hepatic energy charge and increases the lipoperoxide level. In the initial stage of obstructive jaundice, the hepatocytes proliferate associated with activated DNA synthesis probably to compensate hepatic damage; however, prolonged obstructive jaundice induces functional hepatic injury possibly necessitating biliary drainage.

Histomorphometric study of ribs with looser zones in Itai-itai disease

Twelve Looser zones and 17 healing bands of the ribs obtained from autopsy cases of Itai-itai disease were analyzed by bone histomorphometry. Furthermore, proper cancellous tissue of the ribs from 24 autopsy cases of Itai-itai disease with Looser zones or with the healing bands, 27 autopsy cases of Itai-itai disease without such lesions, and 29 control cases were studied by the same method to pursue the histogenesis of Looser zones. In translucent zones of Looser zones, 94% of the cancellous bone was occupied by thick woven bone in which 72% was woven osteoid and 22% was woven mineralized bone. In adjacent scleroses, 71% of the cancellous bone was occupied by woven bone in which 37% was woven mineralized bone, and 34% was woven osteoid; 53% of the cancellous bone consisted of mineralized bone. As compared with those in translucent zones, woven osteoid was decreased, and mineralized bone was increased significantly in the cancellous bone of adjacent scleroses. A significant increase of lamellar mineralized bone and a decrease of woven bone in healing bands were observed as compared with those in Looser zones. These findings suggest that the healing starts from the edge of the Looser zone, and slowly proceeds toward the center. In the cancellous bone of the ribs, the volume, thickness, and surface of osteoid and woven bone were significantly increased in patients with Itai-itai disease, with Looser zones as compared with those without Looser zones. It was concluded that Looser zones seem to occur in severe osteomalacic bones that contain abundant woven bone in the patients of Itai-itai disease.