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101.
102.
Preparation of Asialofetuin-Labeled Liposomes with Encapsulated Human Interferon-γ and Their Uptake by Isolated Rat Hepatocytes 总被引:1,自引:0,他引:1
Ishihara Hiroshi Hara Toshifumi Aramaki Yukihiko Tsuchiya Seishi Hosoi Kaoru 《Pharmaceutical research》1990,7(5):542-546
The selective delivery of human recombinant interferon (IFN)- to isolated rat hepatocytes was studied with asialofetuin (AF)-labeled liposomes. AF-liposomes containing buffer solution were initially prepared by the detergent removal method, and IFN- was subsequently encapsulated by the freeze-thawing method without loss of activity. Virtually no free [32P]IFN- was internalized into isolated rat hepatocytes, whereas AF-liposomes containing [32P]IFN- were taken up to a significant degree. Liposomal binding to the hepatocytes (estimated at 4°C) was one-fifth of the uptake (estimated at 37°C). Since the uptake was inhibited by the addition of free AF, AF-liposomes may be taken up by the action of galactose-binding protein on the hepatocytic cell surface. The liposome preparation method reported in this paper provides a useful means for the encapsulation of unstable macromolecules into AF-liposomes. AF-liposomes were found effectively to carry IFN- into hepatocytes in vitro. 相似文献
103.
Nomizu T Tsuchiya A Kanno M Katagata N Watanabe F Yamaki Y Abe R Miki Y 《Breast cancer (Tokyo, Japan)》1997,4(4):239-242
The possible role of germline mutations ofBRCA1 andBRCA2 as causative agents of familial breast cancer was assessed. Their possible involvement in the carcinogenesis of hereditary
breast cancer was investigated using 63 clinically suspect families. Twenty-one lineages (33.3%) had mutations in one of the
twoBRCA genes. This relatively low incidence suggested that germline mutations in unknown genes are involved in the carcinogenesis
of hereditary breast cancer in the Japanese population. However, the clinicopathological features characteristic of hereditary
breast cancer, such as early disease onset, a high incidence of bilateral breast cancer, and a high incidence of multiple
primary carcinomas in other organs were confirmed in the present study. 相似文献
104.
Christians F Connolly D Tsuchiya K True L Loeb L 《International journal of oncology》1995,6(6):1173-1176
DNA replication errors are especially frequent in repetitive DNA sequences, including microsatellites. Thus, microsatellites are sensitive indicators of the genetic instability observed in many types of human cancers, particularly colorectal cancer. We tested prostate carcinomas for the presence of microsatellite alleles not present in normal tissue from the same individuals. Analysis of 7 microsatellites in each of 30 patients revealed instability at only one microsatellite in one tumor. This level of microsatellite instability, considerably lower than that reported previously, may reflect differences in patient pools. We discuss the implications of the genetic stability of prostate cancers relative to other cancers. 相似文献
105.
The incidence and clinicopathologic features of unilateral multicentric breast cancer (UMBC) were studied by mammary gland
serial sectioning in 116 cases of clinically defined monocentric breast cancer (MONBC) examined histopathologically at the
Nagano Cancer Detection Center. UMBC was defined as: 1) histopathologically discontinuous tumors each with an intraductal
spread, 2) at least one tumor-free section separating two tumors, and 3) a large primary tumor and other small secondary tumors.
UMBC was detected in 23 of 116 cases (19.8%), all with one secondary tumor. Primary and secondary tumors were located in the
same quadrant in 34.8% and in different ones in 65.2%. The secondary tumors were <5 mm in size in 56.5%. Secondary tumors,
averaging 8.3 mm in size and 25.5 mm in distance from the primary tumor, were almost exclusively noninvasive carcinomas, including
15 (65.4%) noninvasive ductal carcinomas and several special types. The primary and secondary tumors were of the same histologic
type in 3 of 23 cases. UMBC patients averaged 6 years younger than MONBC patients, and the incidence of UMBC tended to be
higher in younger patients (p<0.1). UMBC tended to occur more frequently in quadrant with an average histologie tumor size
significantly smaller than that in MONBC (p<0.01). The histologie types of the primary tumor in UMBC and MONBC were similar,
with common types predominant. Lymph node metastases tended to be slightly more frequent in MONBC.
This high incidence of UMBC calls for careful attention when considering breast conserving therapy. 相似文献
106.
Tsuchiya T Ikarashi Y Nakamura A 《Journal of long-term effects of medical implants》1995,5(4):243-252
The inhibitory activities on the intercellular gap-junctional communication were investigated using the V79 metabolic cooperation (MC) assay for the detection of tumor-promoting activities of additives such as pigments and phenolic antioxidants. Among six pigments, four chemicals showed inhibitory activities. The inhibitory potencies were ranked in the following order: sudan I > purple 201 > blue 204 > green 202. Sudan I and purple 201 showed stronger inhibitory activities than lithocholic acid, which is known to be a tumor promotor. However, quinizarine and red 225 did not inhibit at any concentration. Relating to eight phenolic antioxidants, four chemicals also showed inhibitory activities. Combining the present findings with previous ones, there are many factors that have tumor-promoting activities via inhibitory action on gap-junctional intercellular communication in biomaterials. 相似文献
107.
Non-suture end-to-end anastomoses between polytetrafluoroethylene graft and vessels for blood access
Sumimoto K Tanaka I Fukuda Y Haruta N Dohi K Ito H Tsuchiya T Ikada Y 《Panminerva medica》1999,41(1):72-77
BACKGROUND: Non-suture end-to-end anastomoses between polytetrafluoroethylene grafts and blood vessels were achieved using absorbable cuff material in experimental and clinical studies. The cuff was made of a synthetic biodegradable material, a lactic-glycolic acid copolymer, similar in composition to conventional absorbable surgical sutures. METHODS: In the experimental study, vascular anastomoses for prosthetic interposition of the infrarenal aorta in rabbits were created using the cuff method. Six months after surgery, the cuff anastomoses sites were examined angiographically and microscopically and found to be patent and smooth without neointimal hyperplasia. RESULTS: The cuff layer had been completely absorbed. The clinical application used a similar technique and involved the creation of forearm bridge graft fistula in twelve patients for hemodialysis. In eight patients, Doppler fistula flow rate ranged from 167 ml/min to 392 ml/min. Ten of the twelve patients continued dialysis uneventfully. The one-year patency rate was 78% (7/9). The longest patency period was 920 days and the graft access continued to maintain sufficient blood flow for hemodialysis. CONCLUSIONS: This absorbable cuff material is therefore well suited for the construction of prosthetic vascular end-to-end anastomoses. 相似文献
108.
Muneta T Sekiya I Tsuchiya M Shinomiya K 《Clinical orthopaedics and related research》1999,(359):151-155
Additional medial patellofemoral ligament reconstruction was performed successfully on six consecutive patients with recurrent dislocation of the patella because of residual patellar instability after medial transfer of the tibial tubercle. A technique for medial patellofemoral ligament reconstruction is described, and complications and postoperative management are discussed. The reconstruction was performed using a double strand hamstring tendon graft in five patients and iliotibial allograft in one. Good stabilization of the patella was achieved in all six patients, resulting in improved confidence in higher levels of activity. The satisfactory outcome of additional medial patellofemoral ligament reconstruction suggests the possibility that the procedure may be part of the optional procedure in proximal realignment for recurrent dislocation of the patella. 相似文献
109.
Rathke cleft cyst: MR and biomedical analysis of cyst content 总被引:17,自引:0,他引:17
Hayashi Y Tachibana O Muramatsu N Tsuchiya H Tada M Arakawa Y Suzuki M Yamashita J 《Journal of computer assisted tomography》1999,23(1):34-38
PURPOSE: At least one type of Rathke cleft cyst has unique MR findings, specifically, high intensity on T1-weighted images and iso- to low intensity on T2-weighted images relative to white matter. To clarify the influence of cyst content on MR images, we analyzed the cyst content by biomedical methods after surgical removal. METHOD: We studied five patients diagnosed with Rathke cleft cyst, whose MR images showed high intensity on T1-weighted images and iso- to low intensity on T2-weighted images. After surgery, total protein and cholesterol levels were quantified, and correlations of protein and cholesterol content with T1 and T2 signal intensities were performed in vitro. RESULTS: All five cysts had very high concentrations of protein (11,700-26,600 mg/dl, mean 17,940 mg/dl) with nearly no cholesterol (at most 2.0 mg/dl). Along with increases in protein concentration in vitro, the signal intensity of T1-weighted images increased, while that of T2-weighted images decreased. In contrast, the cholesterol concentration sequence influenced the signal intensity of neither T1- nor T2-weighted images. CONCLUSION: The unique MR finding of Rathke cleft cysts--high signal intensity on T1-weighted images and low signal intensity on T2-weighted images--might depend mainly on protein concentration, not on cholesterol. 相似文献
110.
Okuda T Wakita K Tsuchiya N Hatsuoka K Koga Y Kaetsu I 《Masui. The Japanese journal of anesthesiology》1999,48(2):141-145
We synthesized poly (DL-lactic acid)-fentanyl composites and compared the duration of analgesia after the administration of a single intrathecal dose of these agents in rats. The drug was injected with an intrathecal catheter into the intrathecal space. Fentanyl composites or plain fentanyl in doses of 2.5 or 25 micrograms were administered, respectively. Animals were then tested for analgesia using the tail-flick test. The release rate of fentanyl from fentanyl composites in vitro was also evaluated. The antinociceptive effect of fentanyl composites (25 micrograms) was significantly longer than that of plain fentanyl. Administration of poly (DL-lactic acid) alone did not induce the antinociceptive effect. Four of 7 animals given plain fentanyl (25 micrograms) exhibited temporary respiratory depression, but none of the animals given fentanyl composites showed this response. In vitro experiments demonstrated a slow release of fentanyl from the fentanyl composites. We conclude that the antinociceptive effect of fentanyl can be prolonged when administered as a poly (DL-lactic acid)-fentanyl composite in the intrathecal space with decreased systemic side effects compared with the plain formulation. 相似文献