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61.
PURPOSE: A wide variety of tumors depend on the dysregulation of Bcl-2 family proteins for survival. The resulting apoptotic block can often provide a mechanism for resistance to anticancer treatments, such as chemotherapy and radiation. This current study evaluates the efficacy of combining systemically delivered Bcl-2 phosphorothioate antisense (Bcl-2 ASO) and radiation for nasopharyngeal cancer therapy. RESULTS: Antisense uptake was unaffected by 0, 3, or 6 Gy radiation. Radiation decreased the fraction of viable C666-1 cells to 60%, with a further decrease to 40% in combination with Bcl-2 ASO. Despite a modest in vitro effect, Bcl-2 ASO alone caused the regression of established xenograft tumors in mice, extending survival by 15 days in a C666-1 and by 6 days in a C15 model. The survival times for mice treated with both Bcl-2 ASO and radiation increased by 52 days in C666-1 and by 20 days in C15 tumors. This combination resulted in a more-than-additive effect in C666-1 tumors. Less impressive gains observed in C15 tumors might be attributable to higher expression of antiapoptotic Bcl-2 family proteins and limited drug distribution in the tumor. Retreatment of C666-1 tumors with the Bcl-2 ASO-radiation combination, however, was effective, resulting in mice surviving for >80 days relative to untreated controls. CONCLUSIONS: Our results show that the Bcl-2 ASO and radiation combination is a highly potent therapy for nasopharyngeal cancer. Further examination of combination therapy with radiation and other Bcl-2 family-targeted anticancer agents in both preclinical and clinical settings is definitely warranted.  相似文献   
62.
BACKGROUND/OBJECTIVE: As prior studies analysed predictive factors for various post-laminectomy spinal deformities in mixed spinal regions, age groups or pathologies, their validity and conclusions were unclear. The objective of this study was to determine predictive factors for worsened cervical or thoracic spinal sagittal alignment following laminectomy or laminotomy for primary intramedullary spinal cord tumours in children. METHODS: In this retrospective study, patients treated between 1980 and 1998 were reviewed. Changes in spinal alignment at the last follow-up compared to the pre-operative state were studied. Factors analysed were age, pre-operative spinal alignment, procedure types (laminectomy or laminoplasty), number of laminae operated, surgery of C2 or T1 laminae, histological grade, presence of post-operative neurological deficit and post-operative radiotherapy. RESULTS: There were 27 patients. The mean age was 5.6 years (range 1.3-14.0 years), and the mean duration of follow-up was 3.7 years (range 0.075-9.9 years). In the cervical-cervicothoracic surgical group (n = 12), alignment worsened post-operatively in 3 patients. The number of laminae operated upon had a statistically significant impact on the development of post-operative kyphosis (p = 0.07). In the thoracic-thoracolumbar surgical group (n = 15), alignment worsened in 9 patients. Procedure types were statistically significantly different, with laminectomy associated with an increased risk of post-operative kyphosis (p = 0.01). All 5 patients who had spinal fusion for worsened post-operative alignment were in the thoracic-thoracolumbar group; no patients in the cervical-cervicothoracic group required spinal fusion (p = 0.047). Other predictive factors did not reach statistical significance (p > 0.05). CONCLUSIONS: Worsened spinal sagittal alignment following laminectomy or laminoplasty and the need for spinal fusion is more common in the thoracic-thoracolumbar region than in the cervical-cervicothoracic region. In the cervical-cervicothoracic region, operation on a greater number of laminae tends to increase the risk of worsened alignment. In the thoracic-thoracolumbar region, laminectomy is associated with worsened alignment, while laminoplasty reduces this risk; also, pre-operative kyphotic deformity tends to increase the risk of worsened alignment post-operatively.  相似文献   
63.
A healthy dietary pattern review for Asian countries is scarce, which is crucial for guiding healthy eating. We reviewed Taiwanese dietary pattern discovery studies. Included were 19 studies, the majority of which employed dimension reduction methods to find dietary patterns associated with various health conditions. To show what is a high or low intake of foods in Taiwan, we also report the average dietary content and the 25th and 75th percentile values of the adult population for six food groups gathered by the Nutrition and Health Survey in Taiwan, 2017–2020. The healthy Taiwanese dietary approach is cohesive across multiple health outcomes occurring at different ages. It is featured with higher intakes of plant-based foods, aquatic foods, and some beneficial ethnic foods (soy products), drinks (tea), and cooking methods (boiling and steaming); lower intakes of fast foods, fatty and processed meats, sugar, salt rich foods/drinks, and fried foods; but with mixed findings for dairy and egg. Yet, the average Taiwanese person consumed many refined staple foods and livestock, but not sufficient vegetables, fruits, whole grains and roots, beans, and nuts. Dairy consumption remains low. In conclusion, Taiwanese discovery studies point to a mortality-lowering total wellbeing dietary pattern consistent with the current knowledge, which discloses potential benefits of soy product, tea, and boiling and steaming.  相似文献   
64.
To examine the effect of a soybean oil emulsion on essential fatty acid, lipid, and glucose metabolism, preterm infants were randomized to receive 0.5 g/kg/d lipid for 5 days (n = 10, group 1) or 0.5 increased to 2.0 g/kg/d over 5 days (n = 11, group 2). Triene/tetraene ratios did not change in group 1, but decreased in group 2. In both groups, plasma phospholipid linoleate (percent and micrograms per milliliter) increased, the increase being greater in group 2. In both groups, percent content of arachidonate and 5,8,11-eicosatrienoate decreased, and that of oleate remained unchanged. In contrast, absolute content of arachidonate and oleate tended to increase, and that of 5,8,11-eicosatrienoate remained unchanged. At a lipid intake of 0.5 g/kg/d, no infants had hyperlipemia. When lipid intake exceeded 1.0 g/kg/d, the frequency of hypertriglyceridemia (triglycerides greater than 200 mg/dL) and free fatty acidemia, with the free fatty acid/molar albumin ratio exceeding 6:1, increased. Plasma glycerol increased slightly, but was substantially less than the rise in enzymatically determined triglycerides. Hyperglycemia was self-limiting and did not require alteration in dextrose intake. Thus, (1) infusion of a soybean oil emulsion at 0.5 to 2.0 g/kg/d maintains essential fatty acid status and phospholipid arachidonate concentrations; (2) significant hyperlipemia occurs when lipid intake exceeds 1.0 g/kg/d; (3) hyperglycemia associated with lipid infusion tends to be self-limiting and may not require alteration in lipid or dextrose intake; and (4) enzymatically determined triglycerides may be used to monitor lipid tolerance, provided that allowance is made for a small but systematic overestimation resulting from the rise in plasma glycerol.  相似文献   
65.
Ectodomain shedding of epidermal growth factor receptor ligands such as transforming growth factor- alpha (TGF-alpha), heparin-binding epidermal growth factor-like growth factor (HBEGF), and amphiregulin (AREG) is considered to be important during implantation. Tumor necrosis factor-alpha converting enzyme (TACE) has been suggested as the major sheddase for these molecules. The objectives of this study are (1) to characterize the expression of TACE in the human placenta throughout gestation; (2) to determine the association between the expression of TACE with TGF-alpha, HBEGF, and AREG; (3) to ascertain whether TACE mediates TGF-alpha, HBEGF, and AREG shedding; and (4) to examine the effect of hypoxia on the expression of TACE. By analyzing a total of 55 villous samples representing different gestational ages, the authors found that TACE was continuously expressed in the placentas throughout gestation and that the levels of TACE were positively correlated with the levels of TGF-alpha, HBEGF, and AREG. Preadministration of a TACE inhibitor in villous explant cultures or transfection of cytotrophoblastic cells with TACE-specific small interference RNA decreased the shedding of HBEGF and AREG. Moreover, hypoxia (2% O(2)) caused an increase in the levels of TACE mRNA and protein in villous explants and primary cytotrophoblastic cells in vitro. These results indicate that oxygen regulates the expression of TACE and that TACE may be important for placental development during human pregnancy.  相似文献   
66.

Purpose

To analyze the gap junction proteins connexin 37 (Cx37) and connexin 43 (Cx43) after subcutaneous transplantation of cryopreserved mouse ovarian tissue.

Methods

Expression of gap junction genes was assessed by immunohistochemistry and real-time polymerase chain reaction (PCR) in transplanted cryopreserved ovarian tissue compared with that of normal ovarian tissue. Apoptosis of ovarian cells was evaluated by using the terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphates nick end-labeling method.

Results

After subcutaneous transplantation, Cx37 and Cx43 mRNA and protein expression were significantly lower in cryopreserved than in normal ovarian tissue. Apoptosis was increased in granulosa cells from antral follicles of the cryopreserved tissue.

Conclusion

After cryopreservation and subcutaneous transplantation of ovarian tissue, proteins forming gap junctions between oocytes and granulosa cells are under-expressed compared with normal controls.  相似文献   
67.
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69.
The antinociception produced by pentazocine, diphenhydramine, promethazine, chlorpheniramine, cyclizine and chlorcyclizine in the rat has been measured with a low-temperature (51.5 degrees C) hot-plate from 15 to 75 min following drug administration. The mean reaction times measured at 15 min and the area under the antinociception curves following administration of pentazocine (5 to 30 mg/kg) were linear. Diphenhydramine, chlorpheniramine, promethazine, cyclizine, and chlorcyclizine showed mild antinociceptive potency. The antinociception produced by SC pentazocine (5 and 10 mg/kg) was potentiated, rather than in a simple additive manner, by simultaneous IP administration of 20 mg/kg of diphenhydramine, promethazine, cyclizine, or chlorpheniramine, but not by chlorcyclizine. After concurrent administration of pentazocine and diphenhydramine, diphenhydramine did not alter pentazocine concentrations in the brain and plasma 15 to 75 min following drug administration, nor did pentazocine change diphenhydramine concentrations. Results of this study demonstrate that pentazocine antinociception can be potentiated by several antihistamines and that the potentiation was not due to a mutual effect on metabolism but rather through an as yet undefined mechanism.  相似文献   
70.
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