Evaluation of preoperative chemotherapy using PET with fluorine-18-fluorodeoxyglucose in breast cancer

We retrospectively investigated the value of PET with fluorine-18 fluorodeoxyglucose (FDG) for preoperative chemotherapy response in patients with locally advanced breast cancer.

METHODS

FDG-PET studies were performed on 16 consecutive patients. All patients had PET studies before chemotherapy, 13 patients between the end of the first cycle and at the midpoint of chemotherapy, and 14 patients before surgery. Visual diagnoses and the standardized uptake values (SUV) of PET scans were compared with pathology findings at surgery and with the results of mammography, ultrasonography (US) or both, which were performed before chemotherapy and before local surgery for residual disease. Each patient's clinical course was monitored for up to 3 yr.

RESULTS

Sensitivity for detection of pathologically proven primary lesions was 100%, 62.5% and 87.5% with FDG-PET, mammography and US, respectively; and sensitivity for detection of initial nodal involvement was 77%, 70% and 87.5%, respectively. Sensitivity for detection of residual primary tumor was 75%, 71.4% and 87.5%, respectively; and sensitivity for detection of residual nodal involvement was 41.6%, 71.4% and 66.6%, respectively. The mean SUV value of primary lesions was 9.4 (range 2.0-20.7, n = 16), with only two lesions showing an SUV below 3. Clinical improvement of primary lesions was seen in all patients; improvement with smaller size and less FDG uptake was visible as early as the second study in 11 patients (69%). Mean SUV values obtained at the second and third studies decreased significantly from those obtained in the first study. In four patients, the disease recurred after breast surgery with high SUV values. The mammograms and sonograms obtained before surgery showed a decrease in the diameter of 6 and 12 primary lesions of the 13 and 14 patients examined, respectively.

CONCLUSION

FDG-PET is valuable for monitoring the effects of preoperative chemotherapy in patients with locally advanced breast cancer with better sensitivity for primary tumor and better specificity for nodal metastasis in comparison with ultrasonography.

[A basic and clinical evaluation of a new immunoradiometric assay kit for human serum tissue polypeptide antigen (TPA)]

A new immunoradiometric assay kit (IRMA) of human serum tissue polypeptide antigen (TPA) based on combination monoclonal antibodies was evaluated. Using a new TPA-IRMA, the procedure of TPA measurement was faster and the range of measurement was more wide than a conventional TPA-IRMA. 89% (76/85 cases) of patients with malignant tumor and 96.4% (27/28) of patients with metastatic malignant tumor were positively detected. This assay of new TPA-M kit is sensitive to the level of serum TPA which is corresponding to a therapy. It is concluded that a new TPA-IRMA is very useful in monitoring and assessing malignant tumors.

[Association between p53 expression and chemosensitivity in advanced and recurrent gastric cancer]

Fifteen cases with very advanced and recurrent gastric carcinoma were treated by 5-FU plus cisplatin. Among them, 6 cases were responder (CR + PR) and 9 cases were nonresponder (NC). In order to select the responder, p53 protein status in the tissue obtained by endoscopical biopsy before chemotherapy was studied. The immunohistochemical method was by the avidin-biotin complex method using anti-p53 protein monoclonal antibody. One CR case showed negative p53 staining and 2 of 5 cases of PR cases exhibited positive p53 staining. The staining of all 9 NC cases was positive. Significantly high p53 protein overexpression in the nonresponder cases was indicated. In conclusion, our result suggested that the immunohistochemical method detecting p53 protein in the biopsy specimen may be useful to predict the effect by chemotherapy.

Mice lacking p27(Kip1) display increased body size, multiple organ hyperplasia, retinal dysplasia, and pituitary tumors

SUMMARY

Mice lacking p27(Kip1) have been created by gene targeting in embryonic stem cells. These mice are larger than the control animals, with thymus, pituitary, and adrenal glands and gonadal organs exhibiting striking enlargement. CDK2 activity is elevated about 10-fold in p27(-/-) thymocytes. Development of ovarian follicles seems to be impaired, resulting in female sterility. Similar to mice with the Rb mutation, the p27(-/-) mice often develop pituitary tumors spontaneously. The retinas of the mutant mice show a disturbed organization of the normal cellular layer pattern. These findings indicate that p27(Kip1) acts to regulate the growth of a variety of cells. Unexpectedly, the cell cycle arrest mediated by TGFbeta, rapamycin, or contact inhibition remained intact in p27(-/-) cells, suggesting that p27(Kip1) is not required in these pathways.

Fibrosis in the peritoneum induced by scirrhous gastric cancer cells may act as "soil" for peritoneal dissemination

BACKGROUND

Peritoneal metastases are one reason for the poor prognosis of scirrhous gastric cancer. However, the mechanism of peritoneal metastasis remains unclear. We therefore investigated the interaction between gastric cancer cells and peritoneal fibroblasts, in vivo and in vitro.

METHODS

A human scirrhous gastric cancer cell line, OCUM-2MD3, and a human peritoneal fibroblast cell line, NF-2P, were established in our laboratory. We then investigated the effect of OCUM-2MD3 cells on the peritoneum of nude mice and on the proliferation of NF-2P cells, the effect of NF-2P cells on the migratory capability of OCUM-2MD3 cells, and the peritoneal fibrosis on the development of peritoneal metastasis.

RESULTS

The proliferation of peritoneal fibroblasts was recognized in areas with and without cancer cell infiltration. Serum-free conditioned medium from the OCUM-2MD3 cells had induced peritoneal fibrosis in vivo and significantly stimulated the proliferation of NF-2P cells in vitro. The molecular weight (molecular weight ratio 25,000-43,000) of the growth factors produced by the OCUM-2MD3 cells was estimated by gel filtration high performance liquid chromatography. The migratory capability of the OCUM-2MD3 cells was significantly increased by the presence of NF-2P cells. Tumorigenicity in mice with peritoneal fibrosis was greater than in mice with normal peritoneum.

CONCLUSIONS

Peritoneal fibrosis, formed by a factor secreted by scirrhous gastric cancer cells, may be congenial environment ("soil") for peritoneal metastases of scirrhous gastric carcinoma.

Concentrations of pyridinoline and deoxypyridinoline in joint tissues from patients with osteoarthritis or rheumatoid arthritis

OBJECTIVE

To assess the usefulness of pyridinoline (Pyr) and deoxypyridinoline (Dpyr), intermolecular crosslinks of collagen, as markers in the evaluation of arthritis, by studying their distribution in tissues from knee joints.

METHODS

Joint tissues (cartilage, bone, synovium) were obtained during operation from 10 patients with osteoarthritis (OA) and 10 patients with rheumatoid arthritis (RA). Synovium was also obtained from 10 non-arthritic (NA) subjects. Hydroxyproline was measured in hydrolysed tissue samples and converted to an equivalent collagen content. The amounts of Pyr and Dpyr crosslinks measured in the hydrolysed samples using a fluorescence technique were expressed as mumol/mol of collagen.

RESULTS

Pyr and Dpyr were distributed in all three tissues, but in different amounts. The ratio of the contents of Pyr and (Pyr:Dpyr) was 50:1 in cartilage, 3:1 in bone, and 25:1 in synovium. OA cartilage had a greater Dpyr content than the RA cartilage, but there was no other significant difference in the contents of Pyr and Dpyr and the ratio Pyr:Dpyr in the joint tissues from patients with OA or RA. In synovium, there was no significant difference between the contents of Pyr and Dpyr and the Pyr:Dpyr ratio among OA, RA, and NA tissues.

CONCLUSION

Both Pyr and Dpyr were located in cartilage, bone, and synovium. A significant amount of Pyr and Dpyr in these joint tissues, especially in synovium, may contribute to the urinary excretion of those crosslinks that is observed in arthritis.

Tc-99m tetrofosmin myocardial perfusion SPECT after dipyridamole combined with low-level exercise in the diagnosis of coronary artery disease

Tc-99m tetrofosmin is a lipophilic, cationic perfusion imaging agent that changes to Tl-201 in detecting coronary artery disease during exercise testing. The purpose of this study is to evaluate the usefulness of Tc-99m tetrofosmin dipyridamole stress imaging combined with low level exercise for the detection of coronary artery disease. We examined 42 patients and 10 normal volunteers who also underwent coronary angiography. A one-day protocol was used: in the stress study, 296 MBq of tetrofosmin was injected and in the rest study 888 MBq was injected. After intravenous administration of dipyridamole (0.142 mg/kg/min for 4 minutes), the patient was exercised on a bicycle ergometer for 3 min (25 Watts). Tetrofosmin was injected 2 minutes after dipyridamole infusion during the exercise. Single photon emission computed tomographic images were obtained 30 minutes after the tracer injection. Images were interpreted as abnormal in 36 of 42 patients with coronary artery disease, and normal in all of 10 normal volunteers. The overall sensitivity of detection of coronary artery disease was 83.3% and the normalcy rate was 100%. The diagnostic values for the detection of significant stenosis in the three major arteries were: LAD sensitivity 83%, specificity 92%; LCX sensitivity 47%, specificity 91%; RCA sensitivity 75%, specificity 83%. Of the 66 arteries with more than 50% stenosis, 48 arteries were correctly identified. Of the 36 with more than 70% stenosis, 31 were identified. Scintigraphic evidence of multivessel disease was found in only 9 patients (50%). A protocol of Tc-99m tetrofosmin SPECT combined with low level exercise after dipyridamole is therefore useful for the detection of the coronary artery disease.

A mechanism of ischemic preconditioning during percutaneous transluminal coronary angioplasty

Manifestation of ischemic preconditioning and its mechanisms during percutaneous transluminal coronary angioplasty (PTCA) was evaluated. Twenty-two patients with angina pectoris, who had one-vessel coronary artery disease of the proximal left anterior descending artery but without visual collateral circulation, underwent elective PTCA performed by balloon inflations of 90 s, repeated three times or more. Changes in standard 12-lead electrocardiogram, hemodynamics and oxygen saturation of the great cardiac vein by a fiber-optic catheter were analyzed. Anginal chest pain occurred in 21 patients (95%) during the first balloon inflation, and in only 9 patients (41%) during the third inflation. In comparison with the first inflation, the third produced less shifts in ST junction (p < 0.01) and peak T (p < 0.01), which were measured and averaged by 4 chest leads from V2 to V5. The heart rate-blood pressure product during the third inflation was equivalent to that during the first. The great cardiac vein oxygen saturation decreased equally during the first and third inflations. However, the ratio of the saturation at reactive hyperemia after balloon deflation to baseline was higher (p < 0.01) in the third than in the first inflation. The adenosine content of the great cardiac vein measured in 11 patients just prior to balloon deflation was also higher (p < 0.05) in the third inflation than the value in the first. Repeated coronary artery occlusion during PTCA could cause ischemic preconditioning, which may be derived from mechanisms common to accelerated reactive hyperemia, for example an increase in intrinsic adenosine levels.

Apoptosis of cultured microglia by the deprivation of macrophage colony-stimulating factor

Promotion of microglial proliferation and differentiation by colony-stimulating factors (CSFs) and disappearances of microglia at the late neonatal stage by decreasing of CSFs have been reported. In this study, the effects of the deprivation of macrophage CSF (M-CSF) on enriched microglia in cultures were examined by cytochemical methods including in situ nick-end labeling for DNA fragmentation, and Carrazi's hematoxylin nuclear staining. When M-CSF was deprived from the culture medium: (1) at least 40% of the cells were weakly labeled by nick-end within 3 h and more than 70% of the cells were clearly labeled by 16 h; and (2) nuclear condensation or fragmentation, and formation of apoptotic bodies were observed within 48 h. LeY-positive immunoreactivity, identified as a characteristic of cells undergoing apoptosis, was observed on cells positively labeled by nick-end and condensed nucleus, and ones budding apoptotic bodies. From these results, it is conceivable that microglia undergo apoptosis when M-CSF is deprived from the culture medium and, therefore, require CSFs for their survival. This in vitro phenomenon suggests that one of the mechanisms of microglial disappearance in vivo after synaptogenesis may be due to apoptosis by decreasing level of CSFs.

[Malignant lymphoma of the chest wall in a patient with chronic empyema]

A 76-year-old man presented with the chief complaints of appetite loss and general fatigue. He was admitted with the initial diagnosis of empyema necessitatis, and right thoracic drainage was performed. Nevertheless, the subcutaneous mass in the right side of the chest wall did not shrink, and examination of a specimen obtained by percutaneous needle biopsy resulted in the diagnosis of non-Hodgkin's lymphoma, intermediate lymphocytic type. The patient was treated with Adriamycin, vincristine, prednisolone, and cyclophosphamide, but died of pneumonia and cachexia five months after symptoms first appeared. The diagnosis of intermediate lymphocytic lymphoma, B cell type was made at autopsy. Only 53 cases of malignant lymphoma associated with chronic empyema have been reported in Japan. Surgery was often not done because of the patient's advanced age or poor pulmonary function; diagnosis was often difficult. However, review of the 53 reported cases suggested that resection of the tumor, if possible, would improve the prognosis. Malignant lymphoma should be considered when there is chronic empyema, because such cases are now being reported more frequently.

[Bone resorption markers]

For many years, only two bone resorption markers, urinary hydroxyproline and serum tartrate-resistant acid phosphatase, have been clinically employed. However, these two markers have lacked the sensitivity and specificity to bone resorption. In the late 1980s, pyridinoline (Pyr) and deoxypyridinoline (Dpyr) which are mature crosslinks inter-molecular of collagen, were proposed as bone resorption markers. After newly synthesized collagen is incorporated into bone matrix, Pyr, Dpyr are synthesized by the post-translational modification of collagen molecules. Pyridinoline crosslinks occur in type I collagen at two sites, the carboxy- and amino- terminal telopeptides to helix. At the time of bone resorption, Pyr, Dpyr and amino-, and carboxy- terminal crosslinked telopeptides of type I collagen are excreted into the circulation through collagen degradation. Because the crosslinks and crosslinked telopeptides do not exist at the time of synthesis of collagen, the assay for the crosslinks and telopeptides are specific to bone resorption. Recently, novel assays for measuring crosslinked telopeptides have been developed. Amino-terminal pyridinolines crosslinked telopeptides (NTx) and carboxy-terminal telopeptide of type I collagen (CrossLaps) is assayed in urine, and carboxy-terminal pyridinolines crosslinked telopeptides (ICTP) is assayed in serum. Because those markers are specific to bone resorption, they are expected to reflect the minimum amount of bone resorption in postmenopausal women and osteoporosis. We reviewed the background of Pyr and cross-linked telopeptides markers and compared the performance of these bone resorption markers in the bone turnover in postmenopause and established osteoporosis.

Relationship between regional abnormality of left ventricular rapid filling and coronary microcirculation disturbance in hypertrophic cardiomyopathy

BACKGROUND AND HYPOTHESIS

To investigate the mechanism of regional left ventricular diastolic filling disturbance in hypertrophic cardiomyopathy (HCM), we assessed the relationship between abnormalities of regional ventricular rapid filling and regional coronary microcirculation using radionuclide ventriculography and exercise 201thallium (201TI) myocardial scintigraphy with sector analysis.

METHODS

Thirty patients with HCM and 14 patients with atypical chest pain syndrome (controls) were studied. Left ventricular images (left anterior oblique view) were obtained by electrocardiogram-gated 99mtechnetium radionuclide angiography and were divided into three sectors radiating from the geometric center. The time-activity curves and their first derivative curves were analyzed, and the peak filling rate (PFR), the ratio of the time-to-peak filling rate per diastolic interval (TPFR/T) were calculated for the global left ventricle and for the lateral and septal sectors. Exercise stress 201TI myocardial scintigraphy was also performed, and early and delayed images were obtained. The regional washout rate (WR) was then evaluated for the lateral and septal sectors.

RESULTS

In HCM patients, the regional PFR in the septal sector (corresponding to the region of hypertrophic myocardium) was 285 +/- 76%/s, and was significantly lower than that in the controls (398 +/- 90%/s, p < 0.01). The regional TPFR/T in the septal sector (32 +/- 10%) was prolonged compared with the value of 21 +/- 5% in the controls (p < 0.05). The regional WR in the septal sector was 21 +/- 9%, and was significantly lower than that in the controls (43 +/- 5%, p < 0.01). Moreover, regional WR correlated positively with regional PFR (r = 0.5, p < 0.05) and showed a weak negative relationship with regional TPFR/T (r = -0.4, p < 0.07) in the septal sector.

CONCLUSIONS

These results suggest that regional impairment of rapid filling might be related to a disturbance of the coronary microcirculation in HCM.

[Bone turnover and clinical tests]

Bone mass is the lifelong result of a balance between bone formation and bone resorption as shown in most metabolic bone diseases including involutional osteoporosis. To date, bone turnover has been precisely assessed by bone histomorphometry made by bone biopsy and also calcium kinetics and balance studies. However, bone histomorphometry is an invasive procedure requiring specialized laboratory for processing and evaluation, and calcium kinetics and balance studies require administration of radioisotopes and long periods of observation. Therefore, these procedures are not suitable for clinical tests of evaluation of bone turnover. Recently several biochemical parameters for bone turnover have been developed and also a number of noninvasive procedures such as single and dual photon absorptiometry, dual energy x-ray absorptiometry, computed tomography and ultrasound velocity, have been developed to quantitate bone mass more sensitively. In this symposium "Bone turnover and clinical tests" five symposists talked and discussed about some biochemical parameters for bone turnover and noninvasive procedures for measurement of bone mass.

[Characteristics of regional sympathetic innervation in diabetic patients with silent myocardial ischemia assessed by 123I-metaiodobenzylguanidine imaging]

The purpose of this study was to clarify any association between clinically detectable silent myocardial ischemia (SMI) and myocardial 123I-metaiodobenzyl-guanidine (MIBG) uptake. Subjects of this study were (1) patients with SMI with diabetes (n = 15), (2) patients with angina pectoris with diabetes (n = 15), (3) patients with SMI without diabetes (n = 8) and (4) normal subjects (n = 23). Subjects underwent planar and single photon-emission-computed tomography (SPECT) imaging 15 min and 3 hours after injection of 123I-MIBG. H/M ratio was significantly lower in diabetic SMI (2.1 +/- 0.3) and non-diabetic SMI (2.3 +/- 0.3) than control subjects (2.6 +/- 0.3). The inferior-to-anterior wall count ratio (I/A) in diabetic SMI group was the lowest among all groups (p < 0.05). A significant difference was observed in relative regional uptake in the inferior segment of the distal left ventricle between SMI and angina group in patients with diabetes mellitus (p < 0.05). The decreased MIBG uptake in the inferior wall may be an important sign of cardiac sympathetic dysfunction, suggesting the abnormalities in cardiac nervous system play an important role in the mechanism of diabetic silent myocardial ischemia.

Fibrosis in the peritoneum induced by scirrhous gastric cancer cells may act as "soil" for peritoneal dissemination

BACKGROUND

Peritoneal metastases are one reason for the poor prognosis of scirrhous gastric cancer. However, the mechanism of peritoneal metastasis remains unclear. We therefore investigated the interaction between gastric cancer cells and peritoneal fibroblasts, in vivo and in vitro.

METHODS

A human scirrhous gastric cancer cell line, OCUM-2MD3, and a human peritoneal fibroblast cell line, NF-2P, were established in our laboratory. We then investigated the effect of OCUM-2MD3 cells on the peritoneum of nude mice and on the proliferation of NF-2P cells, the effect of NF-2P cells on the migratory capability of OCUM-2MD3 cells, and the peritoneal fibrosis on the development of peritoneal metastasis.

RESULTS

The proliferation of peritoneal fibroblasts was recognized in areas with and without cancer cell infiltration. Serum-free conditioned medium from the OCUM-2MD3 cells had induced peritoneal fibrosis in vivo and significantly stimulated the proliferation of NF-2P cells in vitro. The molecular weight (molecular weight ratio 25,000-43,000) of the growth factors produced by the OCUM-2MD3 cells was estimated by gel filtration high performance liquid chromatography. The migratory capability of the OCUM-2MD3 cells was significantly increased by the presence of NF-2P cells. Tumorigenicity in mice with peritoneal fibrosis was greater than in mice with normal peritoneum.

CONCLUSIONS

Peritoneal fibrosis, formed by a factor secreted by scirrhous gastric cancer cells, may be congenial environment ("soil") for peritoneal metastases of scirrhous gastric carcinoma.

Effect of the selective CCKB receptor antagonist LY288513 on conditioned fear stress in rats

In order to investigate the involvement of cholecystokinin (CCK) in the regulation of anxiety, the effect of the selective non-peptide CCKB receptor antagonist LY288513 ((4S, 5R)-N-(4-bromophenyl)-3-oxo-4,5-diphenyl-1-1-pyrazolidinecarboxamide+ ++) on freezing behavior induced by conditioned fear stress was examined using a time-sampling procedure. Rats were individually subjected to 5 min of inescapable electric footshock in a shock chamber. Twenty-four hours after the footshock, the rats were again placed in the shock chamber and observed for 5 min without shocks: this procedure is termed conditioned fear stress. Subcutaneous administration of LY288513 30 min before footshock (0.3 mg/kg) and 30 min before conditioned fear stress (0.03 mg/kg) reduced conditioned freezing. This indicates that LY288513 blocked both the acquisition and expression of conditioned fear. The relatively selective non-peptide CCKA receptor antagonist, lorglumide (D, L-4-(3,4-dichlorobenzoylamino)-5-(diphentylamino)-5-oxo-pent anoic acid), blocked the expression of conditioned fear, though only at a high dose (1.0 mg/kg). The peripheral non-peptide CCKA/B receptor antagonist, loxiglumide (D, L-4-(3,4-dichlorobenzoylamino)-5- (N-3-methoxypropyl-pentylamino)-5-oxo-pentanoic acid), failed to do so. These results suggest that brain CCKB receptors are involved in the regulation of anxiety.

Effects of 2 years' treatment of osteoporosis with 1 alpha-hydroxy vitamin D3 on bone mineral density and incidence of fracture: a placebo-controlled, double-blind prospective study

A two-year double-blind study monitored and evaluated the effects of 1 alpha-hydroxy vitamin D3 (1 alpha(OH)D3) on the lumbar (L2-4BMD) and total body bone mineral densities (TBBMD) and occurrence of fracture in 113 female osteoporotic patients receiving 0.75 micrograms/day of 1 alpha(OH)D3 (n = 57) or a placebo (n = 56) with calcium supplementation in both groups. L2-4BMD increased 1.81.% and 2.32% after one and 2 years in the 1 alpha (OH)D3 group, but decreased 1.89% (P < 0.05) and 0.28% in the placebo group. A significant difference (P < 0.01) existed between the two groups after one year. TBBMD decreased significantly in the placebo group by 3.34% (P < 0.01) and 3.52% after one and 2 years. Six new fractures occurred in the control group, but only two in the 1 alpha(OH)D3 group (Odd's ratio = 0.343, 95% confidence range; 0.0648-1.815). There were no serious adverse effects of the 1 alpha(OH)D3 treatment. It was concluded that two-year treatment with 1 alpha(OH)D3 increased the lumbar BMD and inhibited the decrease in TBBMD. Although it was not significant, new fracture occurrence in the 1 alpha(OH)D3 group was around 1/3 of that in the control group.

Histopathological effects of illudin S, a toxic substance of poisonous mushroom, in rat

1. Rats were dosed orally with illudin S, a toxic substance derived from the poisonous mushroom Lampteromyces japonicus. The digestive tract showed severe damage, whereas the liver, kidney and lung did not show any significant changes. 2. The effects observed became more pronounced with increasing illudin S dose (5, 10 or 20 mg kg-1 body weight). 3. Severe inflammation and oedema were observed in the stomach and moderate changes in the proximal part of the small intestine. 4. Histopathological examination revealed haemorrhagic erosions and marked inflammatory oedema in the gastric mucosa.

Effects of the novel antipsychotic agent 7-(4-[4-(2,3-dichlorophenyl)-1-piperazinyl]butyloxy)-3,4-dihydro -2(1H)-quinolinone (OPC-14597) on prolactin release from the rat anterior pituitary gland

The effects of a novel antipsychotic agent, 7-(4-[4-(2,3-dichlorophenyl)-1-piperazinyl]butyloxy)-3,4-dihydro-2 (1H)-quinolinone (OPC-14597, generic name aripiprazole), on prolactin (PRL) release from isolated rat anterior pituitary slices and on the serum PRL levels were investigated in male rats. In in vitro experiments on the isolated anterior pituitary, the spontaneous PRL release was decreased by talipexole, a dopamine D2 receptor full agonist, in a dose-dependent manner to 36% of the basal release, and the decrease was antagonized by haloperidol, a D2 receptor antagonist. OPC-14597 also decreased the release of PRL at the same concentration range with a maximal decrease to 78%, the potency being weaker than that of talipexole. The decrease in PRL release induced by OPC-14597 was completely antagonized by haloperidol. Moreover, OPC-14597 antagonized the inhibition of PRL release induced by talipexole. In in vivo experiments, haloperidol increased the serum PRL levels to 8 times the basal PRL level, whereas talipexole decreased the levels to 49% of the basal level. OPC-14597 increased the serum PRL levels by 2-fold and also antagonized the talipexole-induced decrease. The hyperprolactinemia induced by estrogen, which was inhibited by talipexole but enhanced by haloperidol, was enhanced by OPC-14597, whereas the hyperprolactinemia induced by reserpine, which was inhibited by talipexole but elevated by haloperidol, was inhibited by OPC-14597. In addition, the OPC-14597-induced inhibition was antagonized by haloperidol. These results suggest that OPC-14597 has a mixed agonist/antagonist profile at D2 receptors on lactotroph cells and thereby exerts either an antagonistic or an agonistic action, depending on the preexisting tone of the dopaminergic neuronal activities.

Interaction of indometacin farnesil, a new nonsteroidal antiinflammatory drug with peripheral blood mononuclear cells from patients with rheumatoid arthritis

Indometacin farnesil (Indo-F) is a prodrug of indomethacin designed to reduce the occurrence of side-effects by esterification of the carboxyl group on indomethacin with farnesol. We have examined the pharmacological kinetics and action of Indo-F in peripheral blood mononuclear cells (PBMNC) and polymorphonuclear leukocytes (PBPNL) from patients with rheumatoid arthritis (RA). PBMNC and PBPNL were obtained from 31 RA patients. Indo-F was incubated with PBMNC or PBPNL in the presence or absence of granulocyte-macrophage colony stimulating factor (GM-CSF) (100 pg/ml) for 3 approximately 7 days, after which the concentrations of Indo-F and indomethacin in the culture supernatants or in the cytoplasm extracts were measured with HPLC. The levels of Indo-F in the culture supernatants were significantly decreased in the presence of PBMNC or PBPNL from either normal individuals or RA patients. Indo-F was found to be taken up by PBMNC as well as by PBPNL from RA patients. Conversion of Indo-F into indomethacin was significantly enhanced by GMCSF in the presence of PBMNC, but not PBPNL. The results indicate that Indo-F is taken up by peripheral blood leukocytes from RA patients. Moreover, the data suggest that monocyte-lineage cells might play an important role in the conversion of Indo-F into indomethacin since GM-CSF markedly facilitated the conversion in the presence of PBMNC, but not PBPNL.

An RNA fragment consisting of the P7 and P9.0 stems and the 3'-terminal guanosine of the Tetrahymena group I intron

On the basis of the nucleotide sequence of Tetrahymena group I intron, we constructed a 31 residue RNA that has the P7 stem and the 3'-terminal guanosine residue (3'-G) with a putative stem-loop structure (P9.0) intervening between them. For this model RNA (P7/P9.0/G), four residues around the guanosine binding site (GBS) in the P7 stem were found to exhibit much lower sensitivities to ribonuclease V1 than those of a variant RNA having adenosine in place of the 3'-G, suggesting that the 3'-G contacts around the GBS. NMR analyses of the imino proton resonances of the P7/P9.0/G RNA indicated that the base pairing in the GBS is retained on the interaction with the 3'-G, and that the two base pairs of the putative P9.0 stem-loop are definitely formed. Comparison of the RNA with its variants with either A (3'-A) or a deletion in place of the 3'-G suggested that the stability of the P9.0 stem-loop is affected by the GBS-3'-G interaction. The melting temperatures of the P9.0 stem-loop were determined from the UV absorbances of these RNAs, which quantitatively indicated that the P9.0 stem-loop is significantly stabilized by the interaction of the GBS with the 3'-G, rather than the 3'-A, and also by direct interaction with divalent cations (Mg2+, Ca2+ or Mn2+). Upon replacement of the G-C base pair by C-G in the GBS of the P7/P9.0/G RNA, the specificity was switched from 3'-G to 3'-A, as in the case of the intact intron.

Serotonergic activation reduces defensive freezing in the conditioned fear paradigm

Our previous study showed that conditioned fear stress (CFS) increased serotonin (5-HT) metabolism in the medial prefrontal cortex and induced freezing behavior. Although these results could support the 5-HT hypothesis of anxiety, the functional significance of the 5-HT response to stress is unclear. In this study, the effects of 5-HT reuptake inhibitors, agonists, antagonists, and diazepam on freezing behavior induced by CFS were examined using a time-sampling procedure. Various doses of test compounds were administered subcutaneously to rats 24 h after the last session of repeated foot-shock for 5 days. Rats were again placed in the shock chamber without shocks 20 min after injections of drugs, and observed. Diazepam (1 mg/kg) and the 5-HT1A agonist ipsapirone (0.5-10 mg/kg) significantly inhibited freezing behavior. L-5-Hydroxytryptophan (with benserazide) and the selective 5-HT reuptake inhibitor citalopram (10 mg/kg) reduced freezing behavior. The 5-HT2 antagonists ICI169,369 and ketanserin failed to change freezing behavior. p-Chlorophenylalanine (200 mg/kg) administered 15 h before the test did not affect freezing. The effect of ipsapirone was not modified in rats with lesions of 5-HT neurons, produced by p-chloroamphetamine (2 x 10 mg/kg). In conclusion, these results suggest the anxiolytic potential of ipsapirone and citalopram, and support the hypothesis that the facilitation of 5-HT neurotransmission decreases anxiety.

[Linear polarized light irradiation around the stellate ganglion area increases skin temperature and blood flow]

We evaluated the effect of linear polarized light irradiation with a SUPER LIZER around the stellate ganglion area on skin temperature and blood flow in healthy adult volunteers. We carried out two experiments (study I and study II). In study I, we investigated one-sided irradiation around the stellate ganglion area or posterior neck on the skin temperature of the bilateral nasus externi and earlobes. In study II, we investigated one-sided irradiation around the stellate ganglion area or posterior neck on the skin temperatures of both hands and skin blood flow on the irradiated side. In study I, irradiation around the stellate ganglion area increased skin temperature on the irradiated sides of the nasus externi (wings of the nose), and in study II, skin temperature and blood flow were increased on the irradiated side of the hands. These results suggest that linear polarized light irradiation with a SUPER LIZER around the stellate ganglion area would be useful and beneficial in clinical therapy.