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131.
Wen-Kai Yang Chao-Kai Kang Chia-Hao Chang An-Di Hsu Tsung-Han Lee Pung-Pung Hwang 《PloS one》2013,8(1)
FXYD proteins are novel regulators of Na+-K+-ATPase (NKA). In fish subjected to salinity challenges, NKA activity in osmoregulatory organs (e.g., gills) is a primary driving force for the many ion transport systems that act in concert to maintain a stable internal environment. Although teleostean FXYD proteins have been identified and investigated, previous studies focused on only a limited group of species. The purposes of the present study were to establish the brackish medaka (Oryzias dancena) as a potential saltwater fish model for osmoregulatory studies and to investigate the diversity of teleostean FXYD expression profiles by comparing two closely related euryhaline model teleosts, brackish medaka and Japanese medaka (O. latipes), upon exposure to salinity changes. Seven members of the FXYD protein family were identified in each medaka species, and the expression of most branchial fxyd genes was salinity-dependent. Among the cloned genes, fxyd11 was expressed specifically in the gills and at a significantly higher level than the other fxyd genes. In the brackish medaka, branchial fxyd11 expression was localized to the NKA-immunoreactive cells in gill epithelia. Furthermore, the FXYD11 protein interacted with the NKA α-subunit and was expressed at a higher level in freshwater-acclimated individuals relative to fish in other salinity groups. The protein sequences and tissue distributions of the FXYD proteins were very similar between the two medaka species, but different expression profiles were observed upon salinity challenge for most branchial fxyd genes. Salinity changes produced different effects on the FXYD11 and NKA α-subunit expression patterns in the gills of the brackish medaka. To our knowledge, this report is the first to focus on FXYD expression in the gills of closely related euryhaline teleosts. Given the advantages conferred by the well-developed Japanese medaka system, we propose the brackish medaka as a saltwater fish model for osmoregulatory studies. 相似文献
132.
Il-Young Hwang Chung Park Thuyvi Luong Kathleen A. Harrison Lutz Birnbaumer John H. Kehrl 《PloS one》2013,8(8)
B lymphocytes are compartmentalized within lymphoid organs. The organization of these compartments depends upon signaling initiated by G-protein linked chemoattractant receptors. To address the importance of the G-proteins Gαi2 and Gαi3 in chemoattractant signaling we created mice lacking both proteins in their B lymphocytes. While bone marrow B cell development and egress is grossly intact; mucosal sites, splenic marginal zones, and lymph nodes essentially lack B cells. There is a partial block in splenic follicular B cell development and a 50-60% reduction in splenic B cells, yet normal numbers of splenic T cells. The absence of Gαi2 and Gαi3 in B cells profoundly disturbs the architecture of lymphoid organs with loss of B cell compartments in the spleen, thymus, lymph nodes, and gastrointestinal tract. This results in a severe disruption of B cell function and a hyper-IgM like syndrome. Beyond the pro-B cell stage, B cells are refractory to chemokine stimulation, and splenic B cells are poorly responsive to antigen receptor engagement. Gαi2 and Gαi3 are therefore critical for B cell chemoattractant receptor signaling and for normal B cell function. These mice provide a worst case scenario of the consequences of losing chemoattractant receptor signaling in B cells. 相似文献
133.
134.
Migyeong Jo Sanghwan Ko Bora Hwang Sung-Won Min Ji Yeon Ha Ji Chul Lee Se-Eun Jang Sang Taek Jung 《Biotechnology and bioengineering》2020,117(8):i-i
The immunoglobulin G (IgG) molecule has a long circulating serum half-life (~3 weeks) through pH- dependent FcRn binding-mediated recycling. To hijack the intracellular trafficking and recycling mechanism of IgG as a way to extend serum persistence of non-antibody therapeutic proteins, we have evolved the ectodomain of a low-affinity human FcγRIIa for enhanced binding to the lower hinge and upper CH2 region of IgG, which is very far from the FcRn binding site (CH2–CH3 interface). High-throughput library screening enabled isolation of an FcγRIIa variant (2A45.1) with 32-fold increased binding affinity to human IgG1 Fc (equilibrium dissociation constant: 9.04 × 10−7 M for wild type FcγRIIa and 2.82 × 10−8 M for 2A45.1) and significantly improved affinity to mouse serum IgG compared to wild type human FcγRIIa. The in vivo pharmacokinetic profile of PD-L1 fused with engineered FcγRIIa (PD-L1–2A45.1) was compared with that of PD-L1 fused with wild type FcγRIIa (PD-L1–wild type FcγRIIa) and human PD-L1 in mice. PD-L1–2A45.1 showed 11.7- and 9.7-fold prolonged circulating half-life (t1/2) compared to PD-L1 when administered intravenously and intraperitoneally, respectively. In addition, the AUCinf of PD-L1–2A45.1 was two-fold higher compared to that of PD-L1–wild type FcγRIIa. These results demonstrate that engineered FcγRIIa fusion offers a novel and successful strategy for prolonging serum half-life of therapeutic proteins. 相似文献
135.
136.
Wesley L Hung Christine Hwang ShangBang Gao Jyothsna Chitturi Ying Wang Hang Li Jean‐Louis Bessereau Mei Zhen 《The EMBO journal》2013,32(12):1745-1760
A neuronal F‐box protein FSN‐1 regulates Caenorhabditis elegans neuromuscular junction development by negatively regulating DLK‐mediated MAPK signalling. In the present study, we show that attenuation of insulin/IGF signalling also contributes to FSN‐1‐dependent synaptic development and function. The aberrant synapse morphology and synaptic transmission in fsn‐1 mutants are partially and specifically rescued by reducing insulin/IGF‐signalling activity in postsynaptic muscles, as well as by reducing the activity of EGL‐3, a prohormone convertase that processes agonistic insulin/IGF ligands INS‐4 and INS‐6, in neurons. FSN‐1 interacts with, and potentiates the ubiquitination of EGL‐3 in vitro, and reduces the EGL‐3 level in vivo. We propose that FSN‐1 may negatively regulate insulin/IGF signalling, in part, through EGL‐3‐dependent insulin‐like ligand processing. 相似文献
137.
Aerobic plate counts (APC), coliforms, Bacillus cereus, Escherichia coli and eight foodborne pathogens were tested in 1008 cheap and junk foods, including candies, dried cakes, chewing gum, chocolate, dried and seasoned seafood, ice cream, and sugary foods. APCs were positive for 342 samples (33·9%), and the majority of the counts were 2–3 log CFU g?1 or ml?1 (average: 1·10 log CFU g?1 or ml?1). Most samples (97·3%) contained no coliforms (average: 0·07 log CFU g?1 or ml?1). Bacillus cereus was detected in 68 samples (average: 0·14 log CFU g?1 or ml?1). Escherichia coli and Listeria monocytogenes were detected in 6 and 1 samples, respectively, whereas other foodborne pathogens were not isolated. The highest bacterial counts were associated with dried and seasoned seafood products and dried cakes, suggesting that appropriate regulations of these food types should be considered. Cheap and junk foods were produced mainly in developing countries, but there were no significant differences in the bacterial counts among different countries of origin. The presence of foodborne pathogens may pose a risk for children. These results suggest that there is cause for deeper concern about the safety of these foods and that effective countermeasures should be established to improve their microbiological safety.
Significance and Impact of the Study
Food safety is especially important for children, but only limited information is available about the microbiological quality of cheap and junk foods that are consumed frequently by primary schoolchildren (e.g. dried cakes, candies and chocolates). The present study investigated the microbial quality of cheap and junk foods, and our results indicate that these foods are a potential health risk for children, therefore, deeper concern about the safety of these foods and effective countermeasures should be established to improve their microbiological safety. The present study may contribute to the development of an appropriate child food safety management system. 相似文献138.
Dae Hwan Lee Ji Hyeon Ahn Joon Ha Park Bing Chun Yan Jeong-Hwi Cho In Hye Kim Jae-Chul Lee Sang-Hun Jang Myoung Hyo Lee In Koo Hwang Seung Myung Moon Bonghee Lee Jun Hwi Cho Hyung-Cheul Shin Jin Sang Kim Moo-Ho Won 《Cellular and molecular neurobiology》2013,33(5):615-624
Aging is an inevitable process that occurs in the whole body system accompanying with many functional and morphological changes. Inflammation is known as one of age-related factors, and inflammatory changes could enhance mortality risk. In this study, we compared immunoreactivities of inflammatory cytokines, such as interleukin (IL)-2 (a pro-inflammatory cytokine), its receptor (IL-2R), IL-4 (an anti-inflammatory cytokine), and its receptor (IL-4R) in the cervical and lumbar spinal cord of young adult (2–3 years old) and aged (10–12 years old) beagle dogs using immunohistochemistry and western blotting. IL-2 and IL-2R-immunoreactive nerve cells were found throughout the gray matter of the cervical and lumbar spinal cord of young adult and aged dogs. In the spinal cord neurons of the aged dog, immunoreactivity and protein levels were apparently increased compared with those in the young adult dog. Change patterns of IL-4- and IL-4R-immunoreactive cells and their protein levels were also similar to those in IL-2 and IL-2R; however, IL-4 and IL-4R immunoreactivity in the periphery of the neuronal cytoplasm in the aged dog was much stronger than that in the young adult dog. These results indicate that the increase of inflammatory cytokines and their receptors in the aged spinal cord might be related to maintaining a balance of inflammatory reaction in the spinal cord during normal aging. 相似文献
139.
Cutaneous mucormycosis is a rare opportunistic infection caused by zygomycetes that can be rapidly fatal if unrecognized. We describe the clinical, histopathological, fungal and molecular features of a case of gangrenous cutaneous mucormycosis. The patient presented with great necrosis on his right forearm at the site of detained intravenous cannula needle. He had type II diabetes and chronic renal insufficiency. KOH mount of black eschar showed many broad, aseptate fungal hyphae with right-angle branching. PAS staining of the tissue sample revealed similar broad hyphae in the dermis and cutis. Fungal culture and ITS sequence analysis identified this fungus as Rhizopus oryzae. As no organ involvement was detected, the patient was diagnosed with primary cutaneous mucormycosis. Considering the poor state of the patient, complete excision of the infectious tissue was performed without skin graft instead of amputation. At the same time, intravenous liposomal amphotericin B was given, starting from a small dosage and increased to a total dosage amount of 5.45 g. The wound recovered well with granulation. We emphasize that early recognition and prompt therapy including the control of the primary diseases were important. In this article, we also reviewed the features of primary cutaneous mucormycosis reported in China over the last 20 years. 相似文献
140.
We investigated a carbon nanoribbon (CNR) using atomistic simulations based on Tersoff–Brenner potential function. The CNR was obtained from a compressed (5,5) carbon nanotube (CNT). The obtained CNR had a cross-sectional view as a binocular telescope structure composed of both sp2 and sp3 bonds. One carbon atom per ten carbon atoms had sp3 bond. For the optimized structures, the residual forces on the CNR were 3-order higher than that on the CNR and the lattice constant of the CNR was higher 0.0624?Å than that of the CNT along the tube axis. The Young's modulus of the CNR was the same as that of the CNT whereas the critical strain of the CNR was significantly lower than that of the CNT because the residual stresses on the CNR was very higher than those on the CNT. The tensile force curve vs. the strain of the CNT was slightly higher than that of the CNR. 相似文献