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.

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.

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.

Pituitary adenylate cyclase-activating polypeptide causes rapid Ca2+ release from intracellular stores and long lasting Ca2+ influx mediated by Na+ influx-dependent membrane depolarization in bovine adrenal chromaffin cells

Pituitary adenylate cyclase-activating polypeptide (PACAP) has been reported to increase intracellular Ca2+ concentrations ([Ca2+]i) and catecholamine release in adrenal chromaffin cells. We measured [Ca2+]i with fura-2 and recorded ion currents and membrane potentials with the whole cell configuration of the patch-clamp technique to elucidate the mechanism of PACAP-induced [Ca2+]i increase in bovine adrenal chromaffin cells. PACAP caused [Ca2+]i to increase due to Ca2+ release and Ca2+ influx, and this was accompanied by membrane depolarization and inward currents. The Ca2+ release was suppressed by ryanodine, an inhibitor of caffeine-sensitive Ca2+ stores, but was unaffected by cinnarizine, an inhibitor of inositol trisphosphate-induced Ca2+ release. Ca2+ influx and inward currents were both inhibited by replacement of extracellular Na+, and Ca2+ influx was inhibited by nicardipine, an L-type Ca2+ channel blocker, or by staurosporine, a protein kinase C (PKC) inhibitor, but was unaffected by a combination of omega- conotoxin-GVIA, omega-agatoxin-IVA, and omega-conotoxin- MVIIC, blockers of N-, P-, and Q-type Ca2+ channels. Moreover, 1-oleoyl-2-acetyl-sn-glycerol, a PKC activator, induced inward currents and Ca2+ influx. These results indicate that PACAP causes both Ca2+ release, mainly from caffeine-sensitive Ca2+ stores, and Ca2+ influx via L-type Ca2+ channels activated by membrane depolarization that depends on PKC-mediated Na+ influx.

Small carcinomas of the thyroid. A long-term follow-up of 867 patients

OBJECTIVE

To determine the adequate extent of surgery for small carcinomas of the thyroid.

DESIGN

Retrospective cohort study of 867 consecutive patients with small carcinomas of the thyroid (lesions < 10 mm in diameter) who were operated on at the Noguchi Thyroid Clinic, Oita, Japan, between 1965 and 1987. Mean follow-up was 12.8 years.

SETTINGS

A center for treatment of thyroid disease, where about 1400 thyroid operations are performed per year.

PATIENTS

Thyroidectomy was performed in patients with a preoperative diagnosis of Graves' disease, Graves' disease with nodules, solitary thyroid nodules, multinodular goiters, cysts, chronic thyroiditis and small carcinomas of the thyroid, in 394, 22, 136, 193, 18, 28, and 76 patients, respectively.

RESULTS

Operations were conservative. Three patients who had adenomatous nodular goiters underwent total thyroidectomy. Modified radical neck dissection was performed in 66 patients. Of these 66 patients, 30 had grossly noticeable nodal metastases and 17 had microscopic metastases. Another 50 patients underwent selective lymph node excision, and 28 patients had nodal metastases. Recurrence from remnants of thyroid was seen in five patients. They were treated by surgery. Recurrence in lymph nodes was observed in five patients, and four of them were successfully treated. Recurrence in bone was observed in two patients; one with recurrence in the femur was successfully treated. Two patients died with recurrent cancer.

CONCLUSIONS

Small carcinomas of the thyroid can be fatal. Total thyroidectomy is unnecessary. Modified radical neck dissection is unnecessary unless gross nodal metastases are present. Long-term follow-up is mandatory. A

Molecular epidemiologic analysis of Japanese patients with molluscum contagiosum

BACKGROUND

Molluscum contagiosum virus (MCV) causes molluscum contagiosum (MC) in both children and adults. Recent studies have revealed that the DNA of MCV can be classified into two major types by restriction enzyme cleavage patterns; however, the relationship between MCV types and the clinical features has not been fully understood. Our study was conducted to examine whether there are geographic differences in the incidence of MCV types and whether a correlation exists between MCV types and the age, sex, and clinical status of the patients.

METHODS

Specimens were obtained from 171 Japanese patients. The total DNA was extracted and digested with the restriction enzymes, BamH I, Hind III, and Cla I, respectively. Specimens were then electrophoresed in agarose gels. The gels were stained with ethidium bromide and photographs were taken under transillumination.

RESULTS

Six different cleavage patterns were observed; they were classified into two major types, MCV 1 and MCV 2, consisting of two MCV 1-variants, and MCV 2 prototype, and three MCV 2-variants. The ratio of MCV 1 to MCV 2 was 13:1. MCV 1 was commonly detected in children (98%) and adult women (92%). MCV 2 was more frequently isolated from adult men (44%) and from patients with human immunodeficiency virus (HIV) infection (75%).

CONCLUSION

MCV types found in Japanese children and adult women were predominantly MCV 1 and less frequently MCV 2. This pattern is similar to that observed in European countries and Australia, suggesting a high frequency and world-wide distribution of MCV 1. The higher incidence of MCV 2 among adult men and HIV-positive patients may indicate that transmission routes of MCV 1 and MCV 2 is somewhat different, of which the latter may be in part by sexual contact.

Activation of sympathetic outflow by recombinant human interleukin-1 beta in conscious rats

The present study was undertaken to determine the effects of interleukin-1 beta (IL-1 beta) on renal sympathetic nerve activity (RSNA), arterial blood pressure (AP), heart rate (HR), and body temperature in conscious rats. Either intravenous or intracerebroventricular administration of IL-1 beta elicited increases in AP, HR, and RSNA accompanied by a rise in body temperature. The maximum changes in AP, HR, and RSNA occurred 10-15 min after intravenous injection of IL-1 beta (100 ng) and 20-25 min after intracerebroventricular injection (5 ng). The responses induced by the intravenous and intracerebroventricular injections lasted for approximately 15-30 min and did not appear when the animals were pretreated with the cyclooxygenase inhibitor indomethacin (10 mg/kg iv). Moreover, intracerebroventricular injection of prostaglandin E2 (1 microgram) produced responses similar to those induced by IL-1 but with shorter latency. Plasma norepinephrine and adrenocorticotropic hormone concentrations were increased after IL-1 beta injection. The results suggested that IL-1 beta augments cardiovascular and sympathetic outflow through the central action of prostaglandin E2 in conscious rats.

Coupling between myosin ATPase cycle and creatinine kinase cycle facilitates cardiac actomyosin sliding in vitro. A clue to mechanical dysfunction during myocardial ischemia

BACKGROUND

There is much evidence to support the favorable effects of the phosphocreatine shuttle on myocardial contraction and relaxation. However, experiments in which cardiac muscle fiber or myofibril was used have not elucidated its precise mechanism.

METHODS AND RESULTS

Active movements of fluorescently labeled actin filaments on a cardiac myosin layer coimmobilized with creatinine kinase (CK) onto a nitrocellulose-coated glass coverslip were studied under various concentrations of adenine nucleotides. At a constant phosphocreatine concentration (5 mmol/L, pH 7.1), the relation of sliding velocity to MgATP concentration followed Michaelis-Menten kinetics. The apparent Km was significantly smaller in the presence of CK (0.041 +/- 0.001 mmol/L) than in the absence of CK (0.080 +/- 0.001 mmol/L), indicating that coattached CK facilitated the propelling of actin filaments by the myosin ATPase. This phenomenon was also seen under acidic conditions (pH 6.7) as well as in the presence of inorganic phosphate (10 mmol/L. At a constant MgATP concentration (1 mmol/L), the inhibitory effect of MgADP on the actin-myosin interaction was weaker in the presence of CK than in the absence of CK. Another ATP-regenerating system, pyruvate kinase and phospho(enol)pyruvate, while maintaining a low ratio of [MgADP] to [MgATP], did not reduce the Km value (0.156 +/- 0.001 mmol/L), suggesting that the effect of coattached CK was not achieved only by prevention of MgADP accumulation.

CONCLUSIONS

Coupling between the ATPase cycle and the CK cycle may serve not only to maintain the ATP concentration within the myofibril but also to provide optimal conditions for cardiac actomyosin interaction. Consideration of this coupling will offer a clue to elucidating the systolic or diastolic dysfunction during myocardial ischemia or reperfusion.

[Reconstruction procedure for full-thickness chest wall defects]

Reconstruction of full-thickness chest wall defects after the total layer resection of the chest wall has been performed on 6 cases. Five of 6 cases had local recurrent of breast carcinoma, one case had a recurrent liposarcoma in the chest wall. The reconstruction procedure of skeletal chest wall used to double soft Marlex mesh. The soft tissue layer of the chest wall was reconstructed with myocutaneous flaps in five cases (four cases using latissimus dorsi, one case using rectus abdominis), with omental pedicle graft and free skin flap in one case. Minor wound complications occurred in 2 in the 6 cases, one case had myocutaneous flap using rectus abdominis, the other case using omental pedicle flap, but any postoperative complications including respiratory insufficiency was not seen with myocutaneous flap using latissimus dorsi. The latissimus dorsi myocutaneous flap was most suitable to cover the soft tissue layer of the chest. We confirmed that Marlex mesh and latissimus dorsi myocutaneous flap were able to reconstructed for large defects of full-thickness chest wall involving the sternum, there were best approach to reconstruction full-thickness chest wall defects after total layer chest wall resection.

Temporary threshold shift of vibratory sensation induced by a vibrating handle and its gripping force

OBJECTIVE

This study examines the effect of the force with which a vibrating handle is gripped on the temporary threshold shift of vibratory sensation (TTSv) induced by hand-arm vibration.

METHODS

Six healthy subjects gripped a handle vibrating with a 1.3 octave-band vibration, with a central frequency of 200 Hz and an intensity of 39.2 m/s2. Exposure was for 1 min and 10 min, respectively. Gripping forces for the 1-min exposure were 5 N, 10 N, 40 N and 80 N, respectively, with 0 N push-pull force. Gripping forces for the 10-min exposure were the same as for the 1-min exposure but omitting 80 N. The vibratory sensation threshold at 125 Hz was measured before and after exposure of an exposed fingertip to vibration. The differences measured determine TTSv.t at time t. TTSv.t determines TTSv.0, that is, the temporary threshold shift of vibratory sensation immediately after exposure to vibration according to the estimate made on the basis of the preceding study. The same experimental conditions were repeated 3 times on different days in a soundproof and thermoregulated room.

RESULTS

Our findings show that TTSv increases significantly with increasing gripping force. We also determined the quantitative relationships between TTSv.0 and gripping force as described by the equation TTSv.0 = exp(kf x F + Cf). where kt and Cf are constants and F is gripping force.

CONCLUSION

This study revealed the importance of ergonomic design in reducing the force with which a vibrating handle is gripped to prevent an adverse effect of local vibration. The equation devised may help in the quantitative assessment of the effect of reduced gripping force.

Biphasic changes in behavioral, endocrine, and sympathetic systems in adjuvant arthritis in Lewis rats

Adjuvant arthritis (AA) is an experimental model for rheumatoid arthritis, and is induced most easily in inbred Lewis rats by an intradermal injection of heat-killed Mycobacterium tuberculosis (MT) in incomplete Freund's adjuvant. Susceptivity to the arthritis in Lewis rats is thought to be related to a defect in their responses of the hypothalamo-pituitary-adrenal (HPA) axis to the disease. Because the use of an inbred strain is necessary for our immunological studies, we examined in Lewis rats changes in behavior, the HPA axis, and sympathetic nerve activities during development of the adjuvant arthritis. Following intradermal injections of heat-killed MT in adjuvant, the arthritis began to develop on day 12, reaching its maximum severity on day 21, and remained at the level for over a month. The body temperature rose from day 0 to 5 (the primary phase--before the onset of the arthritis). It then fell to normal temperature, and again rose from day 10 to 21 (the secondary phase--with fully developed arthritis). The behavioral (physical activity, food, and water intake) and hormonal parameters [plasma adrenocorticotropic hormone (ACTH) and corticosterone levels] also changed in two phases, similar to those observed in the temperature responses. No change in plasma vasopressin level was observed. Sympathetic nerve activities, assessed by changes in plasma noradrenalin levels, increased more in the primary than in the secondary phase. The possible causes for the biphasic changes associated with development of arthritis are discussed.

Inhibitory effect of MK-801 on amantadine-induced dopamine release in the rat striatum

In the present study, we examined the effect of amantadine on extracellular dopamine levels in the rat striatum using an in vivo microdialysis. Perfusion of amantadine (0.1-1 mM) through the microdialysis probe caused an increase both in extracellular dopamine and glutamate levels in rat striatum. Amantadine was found to increase extracellular dopamine concentration in Ca(2+)-dependent manner, but the effect was not abolished by omega-conotoxin. Although intraperitoneal administration of MK-801 [(+)-5-methyl-10, 11-dihydroxy-5H-dibenzo (a,d)cyclohepten-5,10-imine] alone could not significantly alter the concentration of dopamine, it attenuated amantadine-induced increase in dopamine level. These findings suggest that an interaction between dopaminergic and glutamatergic neurotransmission is an important component in the regulation of striatal dopamine levels.

Reproducible alterations of DNA methylation at a specific population of CpG islands during blast formation of peripheral blood lymphocytes

We investigated the changes in the methylation patterns of CpG islands associated with blast formation of human peripheral blood lymphocytes activated by anti-CD3 and interleukin-2 (IL-2), using restriction landmark genomic scanning with a methylation-sensitive restriction enzyme (RLGS-M) system. Of about 2,100 NotI spot/loci which were analyzed, only 10 showed changes, whereas drastic changes have been observed in cases of malignant and SV40 transformation. These changes were highly reproducible for samples from both the same and different individuals. Even the timing of the changes after cultivation was the same. Thus, we concluded that at least the genomic DNA methylation state in vivo was essentially retained in T blast cells activated in vitro by induction with IL-2 and anti-CD3, which are commonly used in biological experiments as well as clinical diagnosis and therapy.

Adrenomedullin-immunoreactive neurons in the paraventricular and supraoptic nuclei of the rat

The existence of adrenomedullin (AM) in the rat hypothalamus was examined by immunohistochemistry. AM-immunoreactive neurons were found in the supraoptic nucleus (SON) and in the magnocellular parts of the paraventricular nucleus (PVN). The co-existence of AM-, oxytocin- and/or vasopressin-immunoreactivity was identified in the same neurons in the hypothalamus. The results suggest that the AM may play a role in neurotransmission or in cardiovascular control with neurohypophyseal hormones.

GABAergic inhibitory inputs to subfornical organ neurons in rat slice preparations

To investigate GABAergic inhibitory inputs to neurons of the subfornical organ (SFO), intracellular recordings were made in rat brain slice preparations. Inhibitory postsynaptic potentials, which occurred spontaneously or were evoked by focal electric stimulation, had reversal potentials of approximately -60 mV, and were almost totally abolished by the GABAA antagonists bicuculline at 3-100 microM or picrotoxin at 50 microM. Following the application of bicuculline or picrotoxin, the resting membrane potentials were decreased by 4-8 mV. GABA at 10-100 microM and the GABAA agonist muscimol at 1-100 microM decreased the membrane resistance and the firing rate in all neurons tested. The reversal potential of the response to muscimol was similar to that for inhibitory postsynaptic potentials. The actions of muscimol persisted in the presence of 1 microM tetrodotoxin, implying that muscimol must act directly on the recorded neurons. These results suggest that there is a tonic inhibitory GABAergic input to SFO neurons which are mainly mediated through GABAA receptors.