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141.
Alzheimer's disease is neuropathologically characterized by amyloid β-protein (Aβ) deposition, resulting in neurotoxicity. Herein, we focused on the prevention of anthocyanins from amyloid-mediated neurodysfunction. The data demonstrated that combined exposure of Aβ(1-40) and Aβ(25-35) to Neuro-2A cells resulted in reactive oxygen species (ROS) production and perturbation of calcium homeostasis. The expressions of LXRα, ApoE, ABCA1, and seladin-1 genes were significantly down-regulated upon Aβ challenge. β-Secretase, the rate-limiting enzyme that catalyzes amyloid precursor protein transform to Aβ, was up-regulated by Aβ treatment. For the duration of Aβ stimulation, malvidin (Mal) or oenin (Oen; malvidin-3-O-glucoside) was added, and the protective effects were observed. Mal and Oen showed protective effects against Aβ-induced neurotoxicity through blocking ROS formation, preserving Ca(2+) homeostasis, and preventing Aβ-mediated perturbation of certain genes involved in Aβ metabolism and cellular defense. The present study implicates anthocyanin as a potential therapeutic candidate for the prevention of amyloid-mediated neurodysfunction. 相似文献
142.
Chang SW Li CF Lee GC Yeh T Shaw JF 《Journal of agricultural and food chemistry》2011,59(12):6710-6719
Candida rugosa lipase (CRL), an important industrial enzyme, has been established, containing several different isoforms which were encoded by the high-identity lip gene family (lip1 to lip7). In this study, we compared the expression and biochemical characterization with three different engineered lip2 constructions in the yeast Pichia pastoris. Our results showed that lip2 (lip2) has an overall improvement of 50% higher production yield (1.446 U/mL) relative to that of nflip2 (0.964 U/mL) at 7 days of cultivation time. Codon-optimized lip2 (colip2) has a 2.3-fold higher production yield (2.182 U/mL) compared to that of lip2 (noncodon-optimized; 1.446 U/mL) and nflip2 (0.964 U/mL), with a cultivation time of 5 days. This finding demonstrated that the removal of the N-terminus and the regional codon optimization of the lip2 gene fragment at the 5' end can greatly increase the expression level of recombinant LIP2 in the P. pastoris system. The distinct biochemical properties of our purified recombinant nfLIP2 and LIP2 suggested that they are potentially useful for various industrial applications. 相似文献
143.
The root uptake of germanium, as well as its phytotoxicity, was demonstrated in 1935 by Geilman and BrÜnger (1) in a study with barley, oat and several other crop plants. They were studied on an artificially prepared soil mediums consisting of sand and peat. Recently, a research work on the germanium uptake by lowland rice was reported by Chino and Tanaka (2) with special reference to the pollution problem. The problem was originated from irrigation water contaminated with industrial waste. Meanwhile, the analogous property of germanium to silicon in chemical behavior can be assumed because of their close positions in the periodic table. 相似文献
144.
The expression of distorted DNA-binding factors was studied in developing zebrafish (Danio rerio) using UV-damaged DNA as the binding target. A strong and high-shifting binding activity was detected in the extracts of
zebrafish early embryos (12 h after fertilization), and the expression of this activity dramatically decreased in 60 to 84-h-old
zebrafish. The embryonic extracts produced a similar pattern of high-shifting complexes after incubating with a CPD-specific
or a 6-4PP-specific probe, while different types of low-shifting complexes were generated by the extracts of 84-h-old larvae.
The formation of high-shifting complexes was suppressed in the presence of NaCl at 0.25 M or higher concentrations, yet the
production of low-shifting complexes was stimulated by increasing salt concentration. The binding activity expressed in zebrafish
embryos was apparently unrelated to NER-associated damage-recognition protein XPA, since two polypeptides recognized by an
anti-human XPA antibody were detected only in 84-h-old zebrafish extracts. A competitive binding assay indicated that both
CPDs and 6-4PPs were recognized by the same binding activity expressed in 12-h-old zebrafish, and this activity contained
at least two protein fractions that were eluted from a DEAE-cellulose column by NaCl at 0.1 M and 0.2 M. UV crosslinking of
the two NaCl eluates to a 6-4PP probe produced covalent complexes with the same electrophoretic mobility except one 34-kDa
complex generated by the 0.1 M NaCl eluate, suggesting the existence of two multisubunit damage-recognition protein complexes
in zebrafish embryos. UV-binding factors found in 12-h-old zebrafish embryos may be involved in processing developmental stage-specific
DNA structures similar to UV-damaged DNA.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
145.
SummaryEffects of temperature on the rate of germination, measured as the reciprocal of the time taken for half the population to germinate, were studied in cineraria cvs Cindy Blue and Cindy Dark Red. The base, optimum and maximum temperatures for germination were derived respectively as 1.6, 24.8 and 37.8°C in cv. Cindy Blue, close to Tb = 1.9, To = 24.5 and Tm = 38.4°C in cv. Cindy Dark Red. All seeds of each cultivar had a common base temperature but needed different thermal times to germinate. Seed of cv. Cindy Dark Red began to germinate after ca. 30°Cd compared with 35°Cd required by cv. Cindy Blue. A thermal time of ca. 50°Cd was required for half the population to germinate in each cultivar and the thermal requirement for germination fraction >0.5 was similar in both cultivars. The base and maximum temperatures for germination were similar to those determined previously for leaf initiation and flower development. 相似文献
146.
BH Cheng CY Lin TF Yeh SS Cheng ST Chang 《Journal of agricultural and food chemistry》2012,60(31):7623-7628
Cinnamomum osmophloeum ct. linalool is one of the chemotypes of the indigenous cinnamon in Taiwan. In this study, hydrodistillation was used for extracting the essential oils (EOs) of C. osmophloeum ct. linalool leaves collected from various plants and seasons, and GC-MS and GC-FID were used to examine variations and contents of the chemical composition in EOs. Moreover, the absolute configuration of the main constituent and its EO content were illustrated by GC-FID with a chiral column. In addition, we also investigated the effect of the extraction time (1, 2, 6, and 10 h) on the yield of EO and the contents of the main constituents. Results from this study revealed that the average EO yield of 12 plants was 3.7%, and linalool accounted for more than 90%. The linalool in the EO was proved to be pure S-(+)-linalool, and its content in the leaves ranged from 28.8 ± 0.3 to 35.1 ± 0.2 mg/g. Furthermore, there were no obvious differences in EO yield and S-(+)-linalool content from various plants and seasons. On the other hand, we also demonstrated that EO and S-(+)-linalool from C. osmophloeum ct. linalool leaves can be completely extracted out by 1 h of hydrodistillation. 相似文献
147.
Bor-Chyuan Su Giun-Yi Hung Yun-Chieh Tu Wei-Chen Yeh Meng-Chieh Lin Jyh-Yih Chen 《Marine drugs》2021,19(2)
Synovial sarcoma is a rare but aggressive soft-tissue sarcoma associated with translocation t(X;18). Metastasis occurs in approximately 50% of all patients, and curative outcomes are difficult to achieve in this group. Since the efficacies of current therapeutic approaches for metastatic synovial sarcoma remain limited, new therapeutic agents are urgently needed. Tilapia piscidin 4 (TP4), a marine antimicrobial peptide, is known to exhibit multiple biological functions, including anti-bacterial, wound-healing, immunomodulatory, and anticancer activities. In the present study, we assessed the anticancer activity of TP4 in human synovial sarcoma cells and determined the underlying mechanisms. We first demonstrated that TP4 can induce necrotic cell death in human synovial sarcoma AsKa-SS and SW982 cells lines. In addition, we saw that TP4 initiates reactive oxygen species (ROS) production and downregulates antioxidant proteins, such as uncoupling protein-2, superoxide dismutase (SOD)-1, and SOD-2. Moreover, TP4-induced mitochondrial hyperpolarization is followed by elevation of mitochondrial ROS. Calcium overload is also triggered by TP4, and cell death can be attenuated by a necrosis inhibitor, ROS scavenger or calcium chelator. In our experiments, TP4 displayed strong anticancer activity in human synovial sarcoma cells by disrupting oxidative status, promoting mitochondrial hyperpolarization and causing calcium overload. 相似文献
148.
To clarify the contributions of the nerves supplying the canine hip joint capsule for clinical application, cadaver study of six healthy mongrel dogs was performed. The pelvises and hindlimbs of cadavers were dissected and fixed in formaldehyde. Innervation of the joint capsule was investigated with the aid of an operative microscope. As a result, the canine hip joint capsule receives multiple innervations from articular branches of four nerves. They are articular nerve fibres of femoral, obturator, cranial gluteal and sciatic nerves from the cranioventral, caudoventral, craniolateral and dorsolateral directions of the joint, respectively. No branch originating from the caudal gluteal nerve was observed innervating the hip joint capsule. Our data provides useful information for research on the canine hip joint, including pain analysis with hip disorders and surgical nerve blockade to relieve pain. 相似文献
149.
Differences in the immunopathogenesis of several strains of infectious bursal disease virus (IBDV) were compared. The strains included a virulent virus (IBDV-IM) and three vaccine viruses that included an intermediate vaccine virus (IBDV-B2) and two mild vaccine viruses (IBDV-Lukert and IBDV-BVM). The most significant differences were found in the systemic effects of these strains. In comparison with other strains, IBDV-IM antigen was detectable for up to 8 days postinfection (PI) in lymphoid tissues that included spleen and cecal tonsils, whereas only a few IBDV-B2- and IBDV-Lukert- and no IBDV-BVM-inoculated birds had detectable IBDV antigen in these tissues. IBDV-IM induced systemic circulating nitrite levels in over 86% of the birds at days 2 and 3 PI. IBDV-IM suppressed most vigorously the splenic mitogenic response on days 3-8 PI. Among the three vaccine strains, IBDV-B2 was the most virulent of the three, inducing a significant suppression of the mitogenic response (P < 0.05) and the most vigorous lesions in the bursa of Fabricius with the highest possible lesion score of 4 at 3 days PI (P < 0.05). IBDV-BVM was the mildest strain, not inducing any detectable lesions in lymphoid tissue at the tested time points. Whereas all IBDV-BVM-inoculated and 67% and 33% of the IBDV-Lukert- and IBDV-B2-inoculated birds, respectively, had detectable IBDV antigen in the bursa at 4 days postchallenge, none of the IBDV-IM-inoculated birds was positive for IBDV by immunohistochemistry. IBDV-IM induced the highest enzyme-linked immunosorbent assay (ELISA) antibody levels detected at days 8-29 PI (P < 0.05) and the best protection against challenge virus replication in comparison with IBDV-B2 and IBDV-Lukert. Only one of five IBDV-BVM-inoculated birds developed anti-IBDV ELISA antibodies at 29 days PI, and none of the birds was protected against IBDV challenge. We speculate that better protection with more virulent strains was due to more systemic antigenic stimulation on the basis of higher replication of IBDV in extrabursal lymphoid tissues. Interestingly, IBDV-IM did not differ from IBDV-B2 and IBDV-Lukert in its ability to induce T cell accumulation in the bursa at 8 days PI and local interferon-gamma induction from days 2 to 5 PI. These results suggested that the local T cell events in the bursa alone may not be indicative of a rapid and protective immune response. 相似文献
150.
Engineered Mild Strains of Papaya ringspot virus for Broader Cross Protection in Cucurbits 总被引:1,自引:0,他引:1
ABSTRACT Papaya ringspot virus (PRSV) HA5-1, a mild mutant of type P Hawaii severe strain (PRSV P-HA), has been widely used for the control of PRSV type P strains in papaya, but did not provide practical protection against PRSV type W strains in cucurbits. In order to widen the protection effectiveness against W strains, chimeric mild strains were constructed from HA5-1 to carry the heterologous 3' genomic region of a type W strain W-CI. Virus accumulation of recombinants and their crossprotection effectiveness against W-CI and P-HA were investigated. In horn melon and squash plants, the recombinant carrying both the heterologous coat protein (CP) coding region and the 3' untranslated region (3'UTR), but not the heterologous CP coding region alone, significantly enhanced the protection against W-CI. The heterologous 3'UTR alone is critical for the enhancement of the protection against W-CI in horn melon, but not in zucchini squash. In papaya, the heterologous CP coding region or 3'UTR alone, but not both together, significantly reduced the effectiveness of cross protection against P-HA. Our recombinants provide broader protection against both type W and P strains in cucurbits; however, the protective effectiveness is also affected by virus accumulation, the organization of the 3' genomic region, and host factors. 相似文献