Design, synthesis, structure-activity relationships, and biological characterization of novel arylalkoxyphenylalkylamine sigma ligands as potential antipsychotic drugs

sigma Receptor antagonists may be effective antipsychotic drugs that do not induce motor side effects caused by ingestion of classical drugs such as haloperidol. We obtained evidence that 1-(2-dipropylaminoethyl)-4-methoxy-6H-dibenzo[b,d]pyran hydrochloride 2a had selective affinity for sigma receptor over dopamine D2 receptor. This compound was designed to eliminate two bonds of apomorphine 1 to produce structural flexibility for the nitrogen atom and to bridge two benzene rings with a -CH2O- bond to maintain the planar structure. In light of the evidence, N, N-dipropyl-2-(4-methoxy-3-benzyloxylphenyl)ethylamine hydrochloride 10b was designed. Since compound 10b had eliminated a biphenyl bond of 6H-dibenzo[b,d]pyran derivative 2a, it might be more released from the rigid structure of apomorphine 1 than compound 2a. The chemical modification of compound 10b led to the discovery that N, N-dipropyl-2- [4-methoxy-3-(2-phenylethoxyl)phenyl]ethylamine hydrochloride 10g (NE- 100), the best compound among arylalkoxyphenylalkylamine derivatives 3, had a high and selective affinity for sigma receptor and had a potent activity in an animal model when the drug was given orally. We report here the design, synthesis, structure-activity relationships, and biological characterization of novel arylalkoxyphenylalkylamine derivatives 3.     

Automatic detection of rapid eye movements by discrete wavelet transform

In order to detect rapid eye movements (REM) automatically, the Discrete Wavelet Transform was applied to each 8-s segment of electrooculogram (EOG) data for 30 min of 8 h of normal sleep. The Haar function was used as an analysing wavelet because this function is similar to the REM waveform. By shifting the phase of the analysing wavelet by pi/4 of the function, 96% of REM could be detected. The artifacts caused by body movements could be detected simultaneously by this method. Computing time required for the detection of REM was only 11 s for 30 min EOG data.     

Pharmacological evidence that tetraethylammonium-sensitive,iberiotoxin-insensitive K+ channels function as a negative feedback element for sympathetic neurotransmission by suppressing ω-conotoxin-GVIA-insensitive Ca2+ channels in the relaxation of rabbit facial vein

Naunyn-Schmiedeberg's Archives of Pharmacology -     

Loss of expression of DNA repair enzymes MGMT,hMLH1, and hMSH2 during tumor progression in gastric cancer

BACKGROUND: Disorders of the DNA repair system that protects against alkylating mutagens are known to play an important role in carcinogenesis. METHODS: We investigated the expression of the DNA repair enzyme that protects against alkylating mutagens, O(6)-methylguanine DNA methyltransferase (MGMT), and the mismatch repair (MMR) enzymes, hMLH1 and hMSH2, in 135 gastric cancer specimens by immunohistochemical means. RESULTS: The immunoreactivity of MGMT and MMR proteins correlated significantly with several clinicopathologic factors. The survival curve in 116 patients showed that a loss of MGMT or hMLH1, but not of hMSH2, correlated with a poor prognosis. Combined evaluation of MGMT and hMLH1 revealed that the survival of patients with negative status for both MGMT and hMLH1 was shortest. However, this significant association between patient survival and MGMT or hMLH1 expression disappeared when early and advanced cancers were separately analyzed, indicating that synchronous losses of MGMT and hMLH1 increase during tumor progression and stage. Further evaluation according to histologic type revealed that loss of MGMT, hMLH1, and hMSH2 expression significantly differed between early and advanced cancer in differentiated-type cancers. In contrast, in undifferentiated-type cancer, loss of MGMT and MMR expression was frequently found even in intramucosal (m) cancer, and no significant difference was found in loss of hMLH1 and hMSH2 between early and advanced cancer. CONCLUSION: These findings demonstrate that the reduced expression of MGMT, hMLH1, and hMSH2 in differentiated-type cancer may play an important role during tumor progression between the early and advanced stage. On the other hand, in undifferentiated-type cancer, loss of MGMT and the MMR proteins appears to be an important event at carcinogenesis or at an earlier step of tumor progression.     

Clinical significance of interstitial collagen deposition at the invading edge in oral cancer: Immunohistochemistry for type I collagen

Background Changes in interstitial collagen in human oral cancer have not yet been fully studied. We examined the relationship between the degree of interstitial collagen deposition at the invading edge of the tumor, and the clinical and pathologic findings in oral squamous cell carcinoma. We also investigated the therapeutic implication of the changes in distribution patterns of collagen deposition by comparing biopsy specimens and surgical specimens. Methods Immunohistochemical staining was performed by the streptavidin-biotin method using antibody against human type I collagen for visualizing interstitial collagen in 50 biopsy and 45 surgical specimens. Results Carcinomas with scanty interstitial collagen in biopsy specimens tended to have highly malignant characteristics. Large carcinomas with scanty deposition both in biopsy and surgical specimens were likely to have positive resection margins in spite of radical surgery. Conclusion Immunostaining patterns for type I collagen of oral squamous cell carcinomas can provide information of importance in determining safe resection margins.     

RNA interference demonstrates a novel role for integrin-linked kinase as a determinant of pancreatic adenocarcinoma cell gemcitabine chemoresistance.

Integrin-linked kinase (ILK) facilitates signal transduction between extracellular events and important intracellular survival pathways involving protein kinase B/Akt. We examined the role of ILK in determining pancreatic adenocarcinoma cellular chemoresistance to the nucleoside analogue gemcitabine. Cellular ILK expression was quantified by Western blot analysis. We examined the effects of overexpression of active ILK and of ILK knockdown induced by RNA interference on gemcitabine chemoresistance. We also examined the effects of modulating ILK expression on gemcitabine-induced caspase 3-mediated apoptosis, phosphorylation status of Akt (Ser473) and glycogen synthase kinase. Overexpression of ILK increased cellular gemcitabine chemoresistance, whereas ILK knockdown induced chemosensitization via increased caspase 3-mediated apoptosis. ILK knockdown attenuated Akt Ser473 and glycogen synthase kinase phosphorylation, whereas overexpression of constitutively active myristoylated Akt was sufficient to induce significant recovery in gemcitabine chemoresistance in the presence of ILK knockdown. Levels of ILK expression affect gemcitabine chemoresistance in pancreatic adenocarcinoma cells. This novel finding suggests that therapies directed against ILK and its downstream signaling targets may have the potential to enhance the efficacy of gemcitabine-based chemotherapy.