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11.
Gastrin-releasing peptide (GRP) has been proposed as a novel regulatory peptide in the reproductive tract. We previously demonstrated that GRP immunoreactivities are found predominantly in the uterine gland epithelial cells of nonpregnant and pregnant cows. The present study focused on the distribution of GRP immunoreactivity and the expression of GRP mRNA in the bovine endometrium during the estrous cycle. Tissues were collected from 21 uterine horns and bodies during the estrous cycle. RT-PCR showed the expected GRP mRNA fragments (284 bp) in the tissues from all stages of the cycle. In situ hybridization results ascertained the expression of the GRP mRNA in the uterine gland epithelial cells and superficial epithelial cells of the endometrium. Positive staining of GRP immunoreactivity in the uterine gland epithelial cells was detected in both the uterine horn and body from all stages of the cycle. In metestrus and diestrus stages, GRP was also detected in the superficial epithelial cells of horn, but not in the body. The degrees of GRP mRNA expression and intensities of GRP immunoreactivity in the endometrium increased from proestrus to diestrus stages. These findings suggest that GRP may be important both in the endometrial remodeling during the estrous cycle and in the implantation and development of blastocysts.  相似文献   
12.
Rhoptry-associated protein 1 (RAP-1) is a targeted vaccine antigen for Babesia bovis and Babesia bigemina infections of cattle. The 60-kDa B. bovis RAP-1 is recognized by antibodies and T lymphocytes from cattle that recovered from infection and were immune to subsequent challenge. Immunization with native or recombinant protein was reported to reduce parasitemias in challenged animals. We recently reported that the NT domain of B. bovis RAP-1 contained immunodominant T-cell epitopes, whereas the repeat-rich CT domain was less immunostimulatory for T lymphocytes from cattle immune to B. bovis. The present study was therefore designed to test the hypothesis that the NT region of RAP-1, used as a vaccine with interleukin-12 and RIBI (catalog no. R-730; RIBI Immunochem Research, Inc., Hamilton, Mont. [now Corixa, Seattle, Wash.]) adjuvant to induce a type 1 response, would prime calves for antibody and T-helper cell responses comparable to or greater than those induced by full-length RAP-1 containing the C-terminal repeats. Furthermore, a type 1 immune response to RAP-1 was hypothesized to induce protection against challenge. Following four inoculations of either recombinant full-length RAP-1 or RAP-1 NT protein, RAP-1-specific immunoglobulin G (IgG) titers, T-lymphocyte proliferation, and gamma interferon production were similar. Similar numbers of NT region peptides were recognized. However, in spite of the presence of strong RAP-1-specific IgG and CD4(+)-T-lymphocyte responses that were recalled upon challenge, neither antigen stimulated a protective immune response. We conclude that successful priming of calves with recombinant RAP-1 and adjuvants that elicit strong Th1 cell and IgG responses is insufficient to protect calves against virulent B. bovis challenge.  相似文献   
13.
14.
Chang MC  Tanaka J 《Biomaterials》2002,23(24):310-4818
FT-IR analysis was performed for the hydroxyapatite (HAp)/collagen (COL) nanocomposite cross-linked by glutaraldehyde (GA). The amide bands I, II and III from COL matrix, and phosphate and carbonate bands from HAp were identified. The amide B band arising from C–H stretching mode showed a sensitive conformation by the degree of cross-linking. The amide I band showed a complicate conformational change by the degree of cross-linking. The characteristic amide I band at 1685 cm−1, which is known as an aging parameter in the biological bone, did not show a monotonous tendency by the degree of cross-linking. The relative contents of the organics in the cross-linked HAp/COL nanocomposite were evaluated as an integration ratio between the amide I band at 1600–1700 cm−1 and PO43− band at 900–1200 cm−1. The increase of the organics content by the cross-linking is enabled by the further organization of Ca2+ ions of HAp crystals in HAp/COL nanocomposite. The complicate conformational behavior in the amide I, II and III bands seems to be affected by the cross-linking induced directional arrangement of HAp/COL nanocomposite fibrils.  相似文献   
15.
BackgroundMultiple phenotypes exist within the classification of severe asthma. However, characteristics of patients with not well-controlled severe asthma have not been well identified.MethodsJapanese patients with asthma (age ≥ 20 years) were enrolled at the Keio University Hospital and its affiliated hospitals in this observational study (Keio Severe Asthma Research Program). Among them, patients with severe asthma (those undergoing Global Initiative for Asthma [GINA] 2018 step 4 or 5 treatment) were included in this analysis and investigated clinical characteristics based on asthma control status.ResultsOf the 154 patients (men, 46.8%; age, 60.1 ± 14.9 years), 87 (56.5%) had not well-controlled (partly controlled and uncontrolled) asthma (GINA step 4, 42 patients; step 5, 45 patients). Overall, there were no significant differences in clinical characteristics between patients with well-controlled and not well-controlled asthma. However, cluster analysis revealed that distinct 5 clusters (cluster 1, well-controlled; cluster 2, eosinophilic; cluster 3, non–type 2 inflammation; cluster 4, high periostin; and cluster 5, late-onset type 2 inflammation), and clusters 2–5 were not well-controlled. Among them, cluster 3 was characterized by low eosinophil counts, low periostin levels, and less frequent olfactory disturbance, and this cluster had the worst asthma control.ConclusionsJapanese patients with severe asthma were divided into well-controlled and not-well controlled asthma, and we confirmed heterogeneity of not well-controlled severe asthma. These patients, especially non-type 2 phenotype, require a further therapeutic approach. (University Hospital Medical Information Network Clinical Trials Registry, UMIN000002980)  相似文献   
16.
We developed a novel technique to improve tendon-bone attachment by hybridizing calcium phosphate (CaP) with tendons using an alternate soaking process. We characterized the deposited CaP on or in tendons and determined the healing process of anterior cruciate ligament (ACL) grafts by implanting CaP-hybridized free tendons in bone tunnels intra-articularly. Tendons to be implanted were alternately soaked 10 times in a Ca-containing solution and a PO(4)-containing solution for 30 s each. Treated tendons had ash contents threefold that of untreated tendons. Low-crystallinity apatite was found on or in treated tendons. In animal experiments, the CaP-hybridized tendon exhibited osteoclasts at the tendon-bone interface at 5 days after operation. At 2 weeks after operation, there were more osteoclasts and osteoblasts around the tendon than at 5 days after operation. Directly bonded areas were partially found between the implanted tendon and newly formed bone. The formation of a cartilage layer was partially apparent at 3 weeks after operation. The newly formed bone was observed almost around the tendon. We conclude that CaP-hybridized tendons clearly enhance the healing process of ACL grafts at the tendon-bone interface and regenerate a direct insertion-like formation of tendons similar to a normal healthy ACL insertion within 3 weeks after operation.  相似文献   
17.
Culturing of skin fibroblasts in a thin PLGA-collagen hybrid mesh   总被引:12,自引:0,他引:12  
Chen G  Sato T  Ohgushi H  Ushida T  Tateishi T  Tanaka J 《Biomaterials》2005,26(15):2559-2566
A thin biodegradable hybrid mesh of synthetic poly(DL-lactic-co-glycolic acid) (PLGA) and naturally derived collagen was used for three-dimensional culture of human skin fibroblasts. The hybrid mesh was constructed by forming web-like collagen microsponges in the openings of a PLGA knitted mesh. The behaviors of the fibroblasts on the hybrid mesh and PLGA knitted mesh were compared. The efficiency of cell seeding was much higher and the cells grew more quickly in the hybrid mesh than in the PLGA mesh. The fibroblasts in the PLGA mesh grew from the peripheral PLGA fibers toward the centers of the openings, while those in the hybrid mesh also grew from the collagen microsponges in the openings of the mesh resulting in a more homogenous growth. The proliferated cells and secreted extracellular matrices were more uniformly distributed in the hybrid mesh than in the PLGA mesh. Histological staining of in vitro cultured fibroblast/mesh implants indicated that the fibroblasts were distributed throughout the hybrid mesh and formed a uniform layer of dermal tissue having almost the same thickness as that of the hybrid mesh. However, the tissue formed in the PLGA mesh was thick adjacent to the PLGA fibers and thin in the center of the openings. Fibroblasts cultured in the hybrid mesh were implanted in the back of nude mouse. Dermal tissues were formed after 2 weeks and became epithelialized after 4 weeks. The results indicate that the web-like collagen microsponges formed in the openings of the PLGA knitted mesh increased the efficiency of cell seeding, improved cell distribution, and therefore facilitated rapid formation of dermal tissue having a uniform thickness. PLGA-collagen hybrid mesh may be useful for skin tissue engineering.  相似文献   
18.
In an effort to clarify the clinical significance of anti-phospholipid antibodies (aPL) detected by enzyme-linked immunosorbent assay (ELISA), we examined the prevalence of anti-cardiolipin antibodies (aCL), anti-beta2-glycoprotein I antibodies (anti-beta2-GPI), antiprothrombin antibodies (anti-PT), and anti-phosphatidylserine/prothrombin antibodies (anti-PS/PT) in 175 patients with systemic lupus erythematosus (SLE) comprising 67 patients with thrombotic complications. The present study showed that positive results of anti-beta2-GPI-ELISA and anti-PS/PT-ELISA could serve as markers of thrombotic complications in patients with SLE, whereas aCL and anti-PT are less reliable as markers of these complications. Furthermore, results of the anti-PS/PT-ELISA correlate best with the occurrence of both arterial and venous thrombosis in patients with SLE.  相似文献   
19.
20.
Adenosquamous carcinoma of the gallbladder   总被引:3,自引:0,他引:3  
BACKGROUND/AIMS: Adenosquamous carcinoma of the gallbladder is relatively rare. Its biological behavior and optimal surgical procedure are still controversial. METHODOLOGY: Clinicopathological factors and proliferating cell nuclear antigen expression were studied in four stage IV adenosquamous carcinoma patients who underwent curative surgery between June 1987 and April 2000, comparing those of 14 stage IV adenocarcinoma patients at the same period. RESULTS: Preoperative radiological evaluation disclosed a mass invading to the adjacent organs in all cases (liver in 3 cases, and liver and stomach in one case). Three patients (case 1, 2 and 3: well-differentiated adenosquamous carcinomas) were all alive without recurrence in 10, 7, and 2 years after surgery. In contrast, the remaining patient (case 4: moderately differentiated adenosquamous carcinoma) with positive pathologic factors (lymph node metastasis, vascular invasion, etc) deceased one year after surgery due to peritoneal dissemination. When survival rate of adenosquamous carcinoma was compared, the prognosis of adenosquamous carcinoma was significantly better than that of adenocarcinoma (P = 0.0103). Comparison of pathological factors revealed that the frequency of lymph node metastasis was significantly higher in adenocarcinoma than in adenosquamous carcinoma (P = 0.004). Consistent with these findings, the positivity rate of proliferating cell nuclear antigen labeling was significantly lower in squamous carcinoma component, compared with adenosquamous component (P < 0.0001) or adenocarcinoma (P < 0.0001). CONCLUSIONS: Even in patients with stage IV adenosquamous carcinoma of the gallbladder, a long-term survival may be obtained by curative surgery if the squamous component is predominant.  相似文献   
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