The NK1 receptor and its participation in the synergistic enhancement of corneal epithelial migration by substance P and insulin-like growth factor-1

1. We have previously shown that substance P (SP) and insulin-like growth factor-1 (IGF-1) act synergistically to enhance the migration of rabbit corneal epithelial cells in an organ culture model. The present study was designed to identify the epithelial cell SP receptor that participates in this synergistic effect.
2. Rabbit corneal blocks were incubated for 24 h, then the length of the path of epithelial migration was measured. Reagents tried in the TC-199 culture medium, in the presence or absence of IGF-1, were: SP, agonists of tachykinin receptors NK₁, NK₂ or NK₃ and antagonists of tachykinin receptors NK₁ or NK₂.
3. The binding characteristics of SP receptors were examined in rabbit cultured corneal epithelial cells by binding assays with [¹²⁵I]-SP in the presence or absence of excess unlabelled SP or ligands of NK₁, NK₂ or NK₃ receptors.
4. As was demonstrated previously, SP and IGF-1 stimulated epithelial migration when they were added to the culture medium together, but individually they had no effect. NK₁ agonists had the same synergistic effect with IGF-1 as did SP, but the NK₂ and NK₃ agonists did not. Furthermore, the NK₁ antagonist abolished the synergistic effect of SP and IGF-1, but the NK₂ antagonist had no effect.
5. SP bound specifically to rabbit cultured corneal epithelial cells. The binding affinity was 0.44 nM and there were 2.43×10⁴ binding sites per cell. The NK₁ ligand competed, in a dose-dependent fashion, with the binding of SP to corneal epithelial cells, but neither the NK₂ nor NK₃ ligand affected binding.
6. We conclude that the SP receptor in rabbit corneal epithelial cells is NK₁ and that this receptor participates in the synergistic enhancement of corneal epithelial migration by SP and IGF-1. The precise mechanism(s) of this interaction requires more study. These findings imply that both neural and humoral factors are essential for the maintenance and healing of corneal epithelium.

     

Activity of cytotoxic agents against clear cell carcinoma of the ovary which is intrinsically platinum-refractory

The aim of the present study was to evaluate cytotoxic agents active for clear cell carcinoma of the ovary (OCCA) which is intrinsically platinum-resistant. We first conducted in vitro chemosensitivity tests assessing antitumor activities of Various agents against OCCA using two cell lines (HAC-2 and KK) established from ascites of patients with pure OCCA. The most potent single agent was SN-38 (active substance of CPT-11 in vivo) in both cell lines. The second most potent agent was mitomycin-C (MMC) followed by doxorubicin (DOX) in HAC-2 and DOX followed by MMC in KK, respectively. In vivo chemosensitivity test of agents on HAC-2 transplanted into BALB/C nude mice demonstrated that MMC was most potent, followed by DOX and CPT-11. Moreover, a combination of CPT-11 and MMC exhibited the highest anti-tumor activity in this animal model. Cisplatin, etoposide, and paclitaxel were found to be ineffective in either the in vitro or in vivo experimental system. Clinical trial with a combination of MMC and CPT-11 are warranted in patients with OCCA.     

Induction of apoptosis in ovarian carcinoma cell line by glucocorticoids, and sex steroid hormones

We investigated the interactions in the KOC-2s human ovarian cancer cells on the effect of glucocorticoids, and sex steroid hormones in ovarian carcinomas. At 10(-8) M to 10(-5) M, dexamethasone (Dex) decreased the number of cells by 75-80% (p<0.001). At 10(-8) M and 10(-7) M, hydrocortisone (HC) decreased the number by 50% (p<0.01); at 10(-6) M and 10(-5) M, the decrease in number of cells was 65%. The E-2 decrease in number was not statistically significant. Progesterone (PG) showed at 10(-8) to 10(-6) M an increase in number of cells, however, at 10(-5) M it was decreased by 70% with a significant difference (p<0.001). Dex (10(-8)-10(-5) M), HC (10(-8)-10(-5) M) and PG (10(-5) M) produced internucleosomal cleavage of DNA into fragments with multiples of 180 to 200 bp. The TNF-alpha with addition of Dex (10(-8)-10(-5) M) and HC (10(-8)-10(-5) M) was increased after 24 h, 48 h (p<0.001); however, gradually decrease after 72 h. When PG (10(-8)-10(-5) M) was added, PG (10(-5) M) increased the secretion of TNF-alpha after 72 h. Our findings demonstrate that glucocorticoids, and PG directly induce apoptotic DNA fragmentation of KOC-2s cells. However, the secretion of TNF-alpha and expression of Fas antigen were totally different in these substances. These data provide a basis for future studies on the mechanisms of apoptotic effect of glucocorticoids, and PG and the therapeutic effects of these substances.     

FDG-PET for the evaluation of tumor viability after anticancer therapy

To evaluate positron emission tomography with¹⁸F-fluorodeoxy glucose (FDG-PET) as an diagnostic tool to determine tumor viability after anticancer therapy, fourteen patients were examined by FDG-PET after the end of the treatment. The lesions with residual viable tumor cells showed higher uptake of FDG than surrounding normal soft tissue. The lesions, in which tumor viability was lost or very low, showed higher uptake of FDG in four cases and similar uptake to normal soft tissue in three cases. The residual increased uptake of FDG was considered to be caused by remaining tumor cells and/or inflammatory reaction to anticancer treatment. FDG-PET after anticancer treatment should be interpreted by considering the reaction due to the treatment and the partial volume artifact of PET caused by the limited spatial resolution.     

The urinary excretion of pyridinium cross-links as markers of bone metastasis in breast cancer

The collagen cross-links, pyridinoline (Pyr) and deoxypyridinoline (D-Pyr) excreted in urine have recently been suggested as new markers of bone metastasis. In a pilot study we measured Pyr and D-Pyr in 61 patients with breast cancer, 16 with known bone metastasis and 45 with no recognized metastasis in bone. Twenty healthy female subjects were also measured as controls. The mean values (+/-SD) of Pyr and D-Pyr in the group with bone metastasis were significantly higher (Pyr: p<0.01, D-Pyr: p <0.05) than those in the group without bone metastasis and in the control group. The mean (+/-SD) values of postmenopausal women were significantly higher than those of premenopausal in the group without bone metastasis (p<0.05) and in the control group (p<0.01). Therefore, the effect of menopause should be taken into account in the diagnosis of bone metastasis by assays of Pyr and D-Pyr. Setting the cut-off values (mean + 2SD of the values of control) for pre and postmenopausal patients, the accuracy for Pyr was 71.4% in premenopausal and 75.8% in postmenopausal patients; and for D-Pyr it was 71.4% and 78.8% respectively. We consider that measurement of urinary collagen cross-links assays can contribute to the early detection of metastatic spread to bone in breast cancer.     

Cytotoxic impacts on the tumorigenesis and transplantability of ovarian teratoma in lt/sv mouse

The incidence and transplantability of ovarian teratoma in LT/Sv mice were examined following cisplatin treatment at the age of 16 days, and compared to those in the control group. Cisplatin had not affected the emergence of egg cleavage, which simultaneously appeared in the mouse ovaries in both groups. Although 7 teratomas, occasionally transplantable, developed in the control mice aged over 30 days, only 2 tumors occurred in cisplatin-treated mice at the age of 120 days and they were not transplantable. The results suggest that cisplatin might influence the tumorigenic process after egg cleavage, or transplantability of teratoma.     

Signal separation of background EEG and spike by using morphological filter

A signal separation method for extracting background electroencephalogram (EEG) from EEG containing spikes was proposed. Morphological filters were designed for extracting spike waveforms, and then the background EEG was obtained by subtracting the detected spike waveforms from the EEG with spike. The proposed method was evaluated by using simulated EEG data, which consisted of a summation of EEG without spike and model waveform of typical spike. The background EEG separated by the method was processed by the automatic background EEG interpretation.     

Simple scintigraphic parameters with Tc-99m galactosyl human serum albumin for clinical staging of chronic hepatocellular dysfunction

Technetium-99m labeled diethylenetriaminepentaacetic acid (DTPA)-galactosyl human serum albumin (GSA) has been used for hepatocellular functional evaluation. This study proposed new and simple parameters to overcome the limitations of conventional parameters, and they were applied to the clinical staging of chronic liver dysfunction. The study group consisted of 93 patients including 81 with liver dysfunction and 12 control patients. In addition to the two conventional parameters, namely, receptor index (LHL15 = liver count divided by the sum of liver and heart counts at 15 minutes) and clearance index (HH15 = heart count at 15 minutes divided by the heart count at 3 minutes), 6 new parameters for Tc-99m GSA uptake and clearance were generated. The conventional receptor index of LHL15 showed a large variation depending on the size of region of interest (ROI) over the heart. The LHL15 normalized by the ROI size (nLHL15) showed more stable data and a better separation of mild liver dysfunction. A hyperbolic relationship between the LHL15 and HH 15 changed to a linear relationship by using the nLHL15 index. The combination of the liver to heart average count ratio at 15 minutes (LH 15) and T-half (minute) of the heart count also could differentiate each stage well. In conclusion, the use of the ROI-area normalized nLHL is recommended instead of the conventional LHL15. The indices of LH15 and T-half could be alternatively used as practical parameters for clinical staging in liver function.     

Global-motion detection with transparent-motion signals.

A number of experiments were conducted to compare the ability of observers to extract unidirectional and bidirectional (transparent) global-motion signals. In the unidirectional condition, the noise signal consisted of purely randomly-moving dots while in the bidirectional condition, a number of the randomly moving dots were replaced by the same number of dots moving in a specific (secondary-signal) direction. The threshold measure was the minimum number of signal dots required to determine the global-motion direction. For the bidirectional condition, parameters varied were the angular separation between the global-motion and secondary-signal directions and the strength of the secondary signal. Thresholds for unidirectional and bidirectional conditions were the same when the angular difference between global-motion and secondary-signal directions were 90 degrees or greater, i.e. the ability of observers to extract a transparent signal was the same as their ability to extract a unidirectional one. Similarly, with motion-in-depth signals, thresholds for extracting a centripetal signal were not elevated by replacing a number of the randomly-moving noise dots with the same number centrifugally-moving dots. The results are interpreted as indicating that motion signals moving between 90 and 180 degrees to the global-motion direction provide uniform masking of the global-motion signal. For angular separations less than 90 degrees, a suprathreshold secondary signal resulted in threshold elevation. This result could be due, to stronger inhibition from motion units tuned to similar (< 90 degrees) directions, broad directional-tuning of the underlying motion units (changing the task from signal detection to a signal discrimination) or a combination of the two.