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Our previous study has verified that activation of group â metabotropic glutamate receptors (mGluRâ ) in the red nucleus (RN) facilitate the development of neuropathological pain. Here, we further discussed the functions and possible molecular mechanisms of red nucleus mGluR â ¡ (mGluR2 and mGluR3) in the development of neuropathological pain induced by spared nerve injury (SNI). Our results showed that mGluR2 and mGluR3 both were constitutively expressed in the RN of normal rats. At 2 weeks post-SNI, the protein expression of mGluR2 rather than mGluR3 was significantly reduced in the RN contralateral to the nerve lesion. Injection of mGluR2/3 agonist LY379268 into the RN contralateral to the nerve injury at 2 weeks post-SNI significantly attenuated SNI-induced neuropathological pain, this effect was reversed by mGluR2/3 antagonist EGLU instead of selective mGluR3 antagonist ß-NAAG. Intrarubral injection of LY379268 did not alter the PWT of contralateral hindpaw in normal rats, while intrarubral injection of EGLU rather than ß-NAAG provoked a significant mechanical allodynia. Further studies indicated that the expressions of nociceptive factors TNF-α and IL-1ß in the RN were enhanced at 2 weeks post-SNI. Intrarubral injection of LY379268 at 2 weeks post-SNI significantly suppressed the overexpressions of TNF-α and IL-1ß, these effects were reversed by EGLU instead of ß-NAAG. Intrarubral injection of LY379268 did not influence the protein expressions of TNF-α and IL-1ß in normal rats, while intrarubral injection of EGLU rather than ß-NAAG significantly boosted the expressions of TNF-α and IL-1ß. These findings suggest that red nucleus mGluR2 but not mGluR3 mediates inhibitory effect in the development of SNI-induced neuropathological pain by suppressing the expressions of TNF-α and IL-1ß. mGluR â ¡ may be potential targets for drug development and clinical treatment of neuropathological pain.
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Our previous study has identified that glutamate in the red nucleus (RN) facilitates the development of neuropathic pain through metabotropic glutamate receptors (mGluR). Here, we further explored the actions and possible molecular mechanisms of red nucleus mGluR â (mGluR1 and mGluR5) in the development of neuropathic pain induced by spared nerve injury (SNI). Our data indicated that both mGluR1 and mGluR5 were constitutively expressed in the RN of normal rats. Two weeks after SNI, the expressions of mGluR1 and mGluR5 were significantly boosted in the RN contralateral to the nerve injury. Administration of mGluR1 antagonist LY367385 or mGluR5 antagonist MTEP to the RN contralateral to the nerve injury at 2 weeks post-SNI significantly ameliorated SNI-induced neuropathic pain. However, unilateral administration of mGluRâ agonist DHPG to the RN of normal rats provoked a significant mechanical allodynia, this effect could be blocked by LY367385 or MTEP. Further studies indicated that the expressions of TNF-α and IL-1ß in the RN were also elevated at 2 weeks post-SNI. Administration of mGluR1 antagonist LY367385 or mGluR5 antagonist MTEP to the RN at 2 weeks post-SNI significantly inhibited the elevations of TNF-α and IL-1ß. However, administration of mGluR â agonist DHPG to the RN of normal rats significantly enhanced the expressions of TNF-α and IL-1ß, these effects were blocked by LY367385 or MTEP. These results suggest that activation of red nucleus mGluR1 and mGluR5 facilitate the development of neuropathic pain by stimulating the expressions of TNF-α and IL-1ß. mGluR â maybe potential targets for drug development and clinical treatment of neuropathic pain.
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Interleucina-1beta , Neuralgia , Ratos Sprague-Dawley , Receptor de Glutamato Metabotrópico 5 , Receptores de Glutamato Metabotrópico , Núcleo Rubro , Fator de Necrose Tumoral alfa , Animais , Neuralgia/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Receptores de Glutamato Metabotrópico/agonistas , Masculino , Receptor de Glutamato Metabotrópico 5/metabolismo , Receptor de Glutamato Metabotrópico 5/antagonistas & inibidores , Interleucina-1beta/metabolismo , Interleucina-1beta/biossíntese , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Ratos , Núcleo Rubro/metabolismo , Núcleo Rubro/efeitos dos fármacosRESUMO
CpcL-phycobilisomes (CpcL-PBSs) are a reduced type of phycobilisome (PBS) found in several cyanobacteria. They lack the traditional PBS terminal energy emitters, but still show the characteristic red-shifted fluorescence at ~670 nm. We established a method of assembling in vitro a rod-membrane linker protein, CpcL, with phycocyanin, generating complexes with the red-shifted spectral features of CpcL-PBSs. The red-shift arises from the interaction of a conserved key glutamine, Q57 of CpcL in Synechocystis sp. PCC 6803, with a single phycocyanobilin chromophore of trimeric phycocyanin at one of the three ß82-sites. This chromophore is the terminal energy acceptor of CpcL-PBSs and donor to the photosystem(s). This mechanism also operates in PBSs from Acaryochloris marina MBIC11017. We then generated multichromic complexes harvesting light over nearly the complete visible range via the replacement of phycocyanobilin chromophores at sites α84 and ß153 of phycocyanins by phycoerythrobilin and/or phycourobilin. The results demonstrate the rational design of biliprotein-based light-harvesting elements by engineering CpcL and phycocyanins, which broadens the light-harvesting range and accordingly improves the light-harvesting capacity and may be potentially applied in solar energy harvesting.
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Proteínas de Bactérias , Ficobilinas , Ficobilissomas , Ficocianina , Synechocystis , Ficobilissomas/metabolismo , Ficocianina/metabolismo , Ficocianina/química , Synechocystis/metabolismo , Proteínas de Bactérias/metabolismo , Ficobilinas/metabolismo , Ficobilinas/química , Cianobactérias/metabolismoRESUMO
Ameson portunus, the recently discovered causative agent of "toothpaste disease" of pond-cultured swimming crabs in China has caused enormous economic losses in aquaculture. Understanding the process of spore germination is helpful to elucidate the molecular mechanism of its invasion of host cells. Here, we obtained mature and germinating spores by isolation and purification and in vitro stimulation, respectively. Then, non-germinated and germinated spores were subjected to the comparative transcriptomic analysis to disclose differential molecular responses of these two stages. The highest germination rate, i.e., 71.45 %, was achieved in 0.01 mol/L KOH germination solution. There were 9,609 significantly differentially expressed genes (DEGs), with 685 up-regulated and 8,924 down-regulated DEGs. The up-regulated genes were significantly enriched in ribosome pathway, and the down-regulated genes were significantly enriched in various metabolic pathways, including carbohydrate metabolism, amino acid metabolism and other metabolism. The results suggested that spores require various carbohydrates and amino acids as energy to support their life activities during germination and synthesize large amounts of ribosomal proteins to provide sites for DNA replication, transcription, translation and protein synthesis of the spores of A. portunus within the host cells. Functional genes related to spore germination, such as protein phosphatase CheZ and aquaporin, were also analyzed. The analysis of transcriptome data and identification of functional genes will help to understand the process of spore germination and invasion.
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Microsporídios , Transcriptoma , Animais , Esporos , Microsporídios/genética , Perfilação da Expressão Gênica , Esporos Bacterianos/genéticaRESUMO
The solute carrier family 4 (SLC4) includes 10 members (SLC4A1-5, SLC4A7-11), which are expressed in multiple tissues in the human body. The SLC4 family members differ in their substrate dependence, charge transport stoichiometry and tissue expression. Their common function is responsible for the transmembrane exchange of multiple ions, which is involved in many important physiological processes, such as erythrocyte CO2 transport and the regulation of cell volume and intracellular pH. In recent years, many studies have focused on the role of SLC4 family members in the occurrence of human diseases. When SLC4 family members have gene mutations, a series of functional disorders will occur in the body, leading to the occurrence of some diseases. This review summarizes the recent progress about the structures, functions and disease correlation of SLC4 members, in order to provide clues for the prevention and treatment of related human diseases.
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Mutação , Proteínas SLC4A , Humanos , Proteínas SLC4A/genética , Proteínas SLC4A/fisiologiaRESUMO
Phycobilisomes, the light-harvesting complexes of cyanobacteria and red algae, are a resource for photosynthetic, photonic and fluorescence labeling elements. They cover an exceptionally broad spectral range, but the complex superstructure and assembly have been an obstacle. By replacing in Synechocystis sp. PCC 6803 the biliverdin reductases, we studied the role of chromophores in the assembly of the phycobilisome core. Introduction of the green-absorbing phycoerythrobilin instead of the red-absorbing phycocyanobilin inhibited aggregation. A novel, trimeric allophycocyanin (Dic-APC) was obtained. In the small (110â kDa) unit, the two chromophores, phycoerythrobilin and phytochromobilin, cover a wide spectral range (550 to 660â nm). Due to efficient energy transfer, it provides an efficient artificial light-harvesting element. Dic-APC was generated inâ vitro by using the contained core-linker, LC , for template-assisted purification and assembly. Labeling the linker provides a method for targeting Dic-APC.
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Cianobactérias , Fotossíntese , Ficobilissomas/química , Ficobilissomas/metabolismo , FluorescênciaRESUMO
Our previous studies have clarified that red nucleus (RN) interleukin (IL)-6 is involved in the maintenance of neuropathic pain and produces a facilitatory effect by activating JAK2/STAT3 and ERK pathways. In this study, we further explored the immune molecular mechanisms of rubral IL-6-mediated descending facilitation at the spinal cord level. IL-6-evoked tactile allodynia was established by injecting recombinant IL-6 into the unilateral RN of naive male rats. Following intrarubral administration of IL-6, obvious tactile allodynia was evoked in the contralateral hindpaw of rats. Meanwhile, the expressions of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α), IL-1ß, and IL-6 were elevated in the contralateral spinal dorsal horn (L4-L6), blocking spinal TNF-α, IL-1ß, or IL-6 with neutralizing antibodies relieved IL-6-evoked tactile allodynia. Conversely, the levels of anti-inflammatory cytokines transforming growth factor-ß (TGF-ß) and IL-10 were reduced in the contralateral spinal dorsal horn (L4-L6), an intrathecal supplement of exogenous TGF-ß, or IL-10 attenuated IL-6-evoked tactile allodynia. Further studies demonstrated that intrarubral pretreatment with JAK2/STAT3 inhibitor AG490 suppressed the elevations of spinal TNF-α, IL-1ß, and IL-6 and promoted the expressions of TGF-ß and IL-10 in IL-6-evoked tactile allodynia rats. However, intrarubral pretreatment with ERK inhibitor PD98059 only restrained the increase in spinal TNF-α and enhanced the expression of spinal IL-10. These findings imply that rubral IL-6 plays descending facilitation and produces algesic effect through upregulating the expressions of spinal pro-inflammatory cytokines TNF-α, IL-1ß, and IL-6 and downregulating the expressions of spinal anti-inflammatory cytokines TGF-ß and IL-10 by activating JAK2/STAT3 and/or ERK pathways, which provides potential therapeutic targets for the treatment of pathological pain.
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BACKGROUND: Ultrasound-triggered microbubble destruction (UTMD) is a widely used noninvasive technology in both military and civilian medicine, which could enhance radiosensitivity of various tumors. However, little information is available regarding the effects of UTMD on radiotherapy for glioblastoma or the underlying mechanism. This study aimed to delineate the effect of UTMD on the radiosensitivity of glioblastoma and the potential involvement of autophagy. METHODS: GL261, U251 cells and orthotopic glioblastoma-bearing mice were treated with ionizing radiation (IR) or IR plus UTMD. Autophagy was observed by confocal microscopy and transmission electron microscopy. Western blotting and immunofluorescence analysis were used to detect progesterone receptor membrane component 1 (PGRMC1), light chain 3 beta 2 (LC3B2) and sequestosome 1 (SQSTM1/p62) levels. Lentiviral vectors or siRNAs transfection, and fluorescent probes staining were used to explore the underlying mechanism. RESULTS: UTMD enhanced the radiosensitivity of glioblastoma in vitro and in vivo (P < 0.01). UTMD inhibited autophagic flux by disrupting autophagosome-lysosome fusion without impairing lysosomal function or autophagosome synthesis in IR-treated glioblastoma cells. Suppression of autophagy by 3-methyladenine, bafilomycin A1 or ATG5 siRNA had no significant effect on UTMD-induced radiosensitization in glioblastoma cells (P < 0.05). Similar results were found when autophagy was induced by rapamycin or ATG5 overexpression (P > 0.05). Furthermore, UTMD inhibited PGRMC1 expression and binding with LC3B2 in IR-exposed glioblastoma cells (P < 0.01). PGRMC1 inhibitor AG-205 or PGRMC1 siRNA pretreatment enhanced UTMD-induced LC3B2 and p62 accumulation in IR-exposed glioblastoma cells, thereby promoting UTMD-mediated radiosensitization (P < 0.05). Moreover, PGRMC1 overexpression abolished UTMD-caused blockade of autophagic degradation, subsequently inhibiting UTMD-induced radiosensitization of glioblastoma cells. Finally, compared with IR plus UTMD group, PGRMC1 overexpression significantly increased tumor size [(3.8 ± 1.1) mm2 vs. (8.0 ± 1.9) mm2, P < 0.05] and decreased survival time [(67.2 ± 2.6) d vs. (40.0 ± 1.2) d, P = 0.0026] in glioblastoma-bearing mice. CONCLUSION: UTMD enhanced the radiosensitivity of glioblastoma partially by disrupting PGRMC1-mediated autophagy.
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Glioblastoma , Animais , Autofagia/genética , Glioblastoma/patologia , Glioblastoma/radioterapia , Humanos , Proteínas de Membrana , Camundongos , Microbolhas , Tolerância a Radiação/genética , Radiação Ionizante , Receptores de ProgesteronaRESUMO
OBJECTIVE: This study aimed to establish a new external quality assessment (EQA) of chromosomal karyotype analysis. METHODS: Chimeric assembly A1 was established by collecting chimeric chromosome images prepared artificially from chromosomally abnormal amniocytes remaining after prenatal diagnosis. Chimeric assembly B1 and nonchimeric assembly C1 were constructed through the collection of chimeric and nonchimeric chromosome images from prenatal diagnosis, respectively. Then, chromosome images were selected randomly from assemblies A1, B1, or C1 to send to 20 technicians via email to verify the validity of a new EQA of chromosomal karyotype analysis. RESULTS: According to the EQA of 20 technicians, 47,XX,+mar from assembly A was easily misdiagnosed as 47,XX,+19 or 47,XXY, and 45,XX,t(13;22) (q10;q10) was misdiagnosed as 45,XX,13S+,-22. The total misdiagnosis rate was 3.8%. For assembly B, 46,X,+mar and 46,X,idic(Y) were easily misdiagnosed as 46,XY and 46,X,+mar, respectively. In addition, some testers missed 47,XXX in 47,XXX[2]/46,XX[48], as well as 47,XX,+18 in 46,XX [47]/47,XX,+18[3], and 45,X and 47,XXX in 46,XX[47]/45,X[2]/47,XXX[1]. The total misdiagnosis rate was 4.2%. All karyo-types from assembly C were correctly diagnosed, although incorrect descriptions used for 4% of cases. CONCLUSION: The quality of chromosome karyotype analysis can be comprehensively evaluated by a new EQA based on assembly A1 or B1.
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Processamento de Imagem Assistida por Computador , Cariotipagem , Diagnóstico Pré-Natal , Feminino , Humanos , Gravidez , China , Transtornos Cromossômicos/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Cariótipo , Cariotipagem/métodos , Diagnóstico Pré-Natal/métodos , Controle de QualidadeRESUMO
Introduction: The role and underlying mechanisms of miR-27b-3p in triple-negative breast cancer (TNBC) remains unclear. Methods: miR-27b-3p expression level was evaluated in 99 TNBC patients with a median follow-up time of 133 months. The biological functions of miR-27b-3p by targeting PPARG were assessed by luciferase reporter assay, CCK-8 assay, Transwell assay, wound healing assay, western blot analysis and xenograft models. Results: High level of miR-27b-3p expression was found to confer poor prognosis in TNBC patients. MiR-27b-3p overexpression increased TNBC cell proliferation, migration, invasion, and metastasis. Our data suggested peroxisome proliferator-activated receptor gamma (PPARG) was a target of miR-27b-3p. The capacity of miR-27b-3p to induce TNBC progression and metastasis depended on its inhibition of the PPARG expression. Furthermore, restoring PPARG expression reversed the effect of miR-27b-3p overexpression. Mechanistically, miR-27b-3p regulated metastasis-related pathways through PPARG by promoting epithelial-mesenchymal transition. By suppressing PPARG, miR-27b-3p could also activate transcription factors Snail and NF-κB, thereby promoting metastasis. Conclusions: miR-27b-3p promotes TNBC progression and metastasis by inhibiting PPARG. MiR-27b-3p may be a potential prognostic marker of TNBC, and PPARG may be a potential molecular therapeutic target of TNBC.
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BACKGROUND: The goal of this study was to determine whether Levey-Jennings charts, which are widely used in clinical laboratories, can be used to create standardized internal quality controls (IQCs) for prenatal molecular diagnosis. METHODS: Aneuploid amniocyte lines with trisomy 13, 21, and 18, and 47,XXY were established by transfection with SV40LTag-pcDNA3.1(-)and combined at different ratios to generate aneuploidy chimeric quality-control cell mixtures A to H. These quality-control cells were then used to calculate the [Formula: see text], [Formula: see text] ±1 standard deviation (SD), [Formula: see text] ±2 SD, and [Formula: see text] ±3 SD values to develop standardized IQCs for methods used for the prenatal diagnosis of aneuploidies such as FISH. RESULTS: Methods for constructing aneuploid amniocyte lines were developed and a set of quality-control cells (A-H) were prepared. The [Formula: see text] ±1 SD, [Formula: see text] ±2 SD, and [Formula: see text] ±3 SD values of these quality-control cells for trisomy 13 and 21 were 10.2 ± 1.7, 10.2 ± 3.4, and 10.2 ± 5.1, and 90.3 ± 2.3, 90.3 ± 4.6, and 90.3 ± 6.9, respectively. Based on the values and Levey-Jennings charts, a set of standardized IQCs for prenatal diagnosis such as FISH were established. CONCLUSIONS: This method resolves the problems of a shortage of quality-control materials and a lack of quality-control charts in prenatal molecular diagnosis such as NIPT, NGS, aCGH/SNP, PCR, and FISH. Levey-Jennings chart-based IQCs for prenatal diagnosis such as FISH can be used to easily monitor whether IQC results are within acceptable limits, and then infer whether the diagnostic results for clinical samples are reliable. We expect that this standardized IQC will be useful for a wide range of molecular diagnostic laboratories.
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Líquido Amniótico/química , Aneuploidia , Transtornos Cromossômicos/diagnóstico , Laboratórios/normas , Diagnóstico Pré-Natal/normas , Transtornos Cromossômicos/genética , Feminino , Humanos , Gravidez , Controle de QualidadeRESUMO
The historical preparation methods of Glycyrrhizae Radix et Rhizoma were summarized and analyzed by consulting relevant literatures of herbal medicines and medical classics. This study also reviewed the records of Glycyrrhizae Radix et Rhizoma processing methods in previous editions of the Chinese Pharmacopoeia and the regulations on processing technology of Glycyrrhizae Radix et Rhizoma decoction pieces in China. This paper summarized the processing history of Glycyrrhizae Radix et Rhizoma and defined the development process of Glycyrrhizae Radix et Rhizoma processing. According to textual research from ancient times to today, there are many ways to process Glycyrrhizae Radix et Rhizoma. The processing methods without auxiliary materials include braising, frying, cooking, simmering and adding such auxiliary materials as wine, vinegar, salt, oil, ginger, honey, water and bile. There are 9 editions of the published Chinese Pharmacopoeia that document the processing of Glycyrrhizae Radix et Rhizoma, and 24 provinces and cities nationwide record the processing of Glycyrrhizae Radix et Rhizoma. At present, the 2015 edition of the Chinese Pharmacopoeia only records the processing technology of Glycyrrhizae Radix et Rhizoma honey, and the honey processing method is still widely usedtoday. Whether or not Zhigancao should be used uniformly for honey-processed Zhigancao today should be based on the processing methods of Chinese herbal medicine and its clinical use in previous ancient medical books. This paper provides a reference and historical basis for subsequent studies on other processing techniques of Glycyrrhizae Radix et Rhizoma, the rational selection of Glycyrrhizae Radix et Rhizoma varieties and the further development and utilization of corresponding medicinal materials.
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Medicamentos de Ervas Chinesas/análise , Triterpenos , China , Extratos Vegetais , Rizoma/químicaAssuntos
Neoplasias Cardíacas/diagnóstico , Ventrículos do Coração/patologia , Neurofibroma/diagnóstico , Adulto , Procedimentos Cirúrgicos Cardíacos , Meios de Contraste/administração & dosagem , Ecocardiografia , Feminino , Neoplasias Cardíacas/patologia , Neoplasias Cardíacas/cirurgia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neurofibroma/patologia , Neurofibroma/cirurgiaRESUMO
INTRODUCTION: The adverse effect of fractures by different aromatase inhibitor (AI) drugs has not been thoroughly assessed in real-world studies. OBJECTIVE: To assess the adverse events of fractures of real-world breast cancer patients caused by AI therapy through the Food and Drug Administration Adverse Event Reporting System (FAERS) database. METHODS: The FAERS data from January 2004 to December 2018 were sorted out and analyzed for correlations between fractures and AI use. Disproportionate analysis and Bayesian analysis were adopted to quantify the signal, the association between the AIs and fractures. The onset time and outcome of fractures after different AI regimens were also compared. RESULTS: Out of 23,064 adverse reports, 657 fracture reports (2.85%) were analyzed. Anastrozole showed a positive association with 4 detection methods, while letrozole and exemestane did so with 2. More exemestane-related reports (44.62%) resulted in initial or prolonged hospitalization than anastrozole (30.12%, p = 0.013) and letrozole (29.43%, p = 0.006). The fracture onset time showed no significant difference among anastrozole, letrozole, and exemestane (median onset time: 46.95, 34.25, and 40.58 months, respectively; p = 0.236). CONCLUSIONS: Anastrozole should be prescribed with more medical care. Analysis of FAERS data identified fracture risk tendencies with AI regimens, which supported continuous monitoring, risk evaluations, and further comparative studies.
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Inibidores da Aromatase/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Fraturas Ósseas/induzido quimicamente , Adolescente , Adulto , Sistemas de Notificação de Reações Adversas a Medicamentos , Idoso , Idoso de 80 Anos ou mais , Aromatase/metabolismo , Inibidores da Aromatase/administração & dosagem , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Feminino , Seguimentos , Fraturas Ósseas/enzimologia , Fraturas Ósseas/patologia , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Estados Unidos , United States Food and Drug Administration , Adulto JovemRESUMO
Phycobilisomes are large light-harvesting complexes attached to the stromal side of thylakoids in cyanobacteria and red algae. They can be remodeled or degraded in response to changing light and nutritional status. Both the core and the peripheral rods of phycobilisomes contain biliproteins. During biliprotein biosynthesis, open-chain tetrapyrrole chromophores are attached covalently to the apoproteins by dedicated lyases. Another set of non-bleaching (Nb) proteins has been implicated in phycobilisome degradation, among them NblA and NblB. We report in vitro experiments with lyases, biliproteins and NblA/B which imply that the situation is more complex than currently discussed: lyases can also detach the chromophores and NblA and NblB can modulate lyase-catalyzed binding and detachment of chromophores in a complex fashion. We show: (i) NblA and NblB can interfere with chromophorylation as well as chromophore detachment of phycobiliprotein, they are generally inhibitors but in some cases enhance the reaction; (ii) NblA and NblB promote dissociation of whole phycobilisomes, cores and, in particular, allophycocyanin trimers; (iii) while NblA and NblB do not interact with each other, both interact with lyases, apo- and holo-biliproteins; (iv) they promote synergistically the lyase-catalyzed chromophorylation of the ß-subunit of the major rod component, CPC; and (v) they modulate lyase-catalyzed and lyase-independent chromophore transfers among biliproteins, with the core protein, ApcF, the rod protein, CpcA, and sensory biliproteins (phytochromes, cyanobacteriochromes) acting as potential traps. The results indicate that NblA/B can cooperate with lyases in remodeling the phycobilisomes to balance the metabolic requirements of acclimating their light-harvesting capacity without straining the overall metabolic economy of the cell.
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Cianobactérias/metabolismo , Complexos de Proteínas Captadores de Luz/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismoRESUMO
Neurofibrillary tangles of hyperphosphorylated tau protein (p-tau) are a key pathological feature of Alzheimer's disease (AD). Tau phosphorylation is suggested to be secondary to amyloid-beta (Aß) accumulation. However, the mechanism by which Aß induces tau phosphorylation in neurons remains unclear. Neurotrophin receptor p75 (p75NTR) is a receptor for Aß and mediates Aß neurotoxicity, implying that p75NTR may mediate Aß-induced tau phosphorylation in AD. Here, we showed that Aß-induced tau hyperphosphorylation and neurodegeneration, including tau phosphorylation, synaptic disorder and neuronal loss, in the brains of both male wild-type (Wt) mice and male P301L transgenic mice (a mouse model of human tauopathy) were alleviated by genetic knockout of p75NTR in the both mouse models. We further confirmed that the activation or inhibition of cyclin-dependent kinase 5 (CDK5) and glycogen synthase kinase-3ß (GSK3ß) significantly changed Aß/p75NTR-mediated p-tau levels in neurons. Treatment of male P301L mice with soluble p75NTR extracellular domain (p75ECD-Fc), which antagonizes the binding of Aß to p75NTR, suppressed tau hyperphosphorylation. Taken together, our findings suggest that p75NTR meditates Aß-induced tau pathology and is a potential druggable target for AD and other tauopathies.
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Peptídeos beta-Amiloides/toxicidade , Receptores de Fator de Crescimento Neural/metabolismo , Tauopatias/metabolismo , Proteínas tau/metabolismo , Animais , Células Cultivadas , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Distribuição Aleatória , Receptores de Fator de Crescimento Neural/administração & dosagem , Receptores de Fator de Crescimento Neural/genética , Tauopatias/tratamento farmacológico , Tauopatias/genética , Proteínas tau/antagonistas & inibidores , Proteínas tau/genéticaRESUMO
Emerging evidence suggests that gut microbiota dysbiosis plays a role in neurodegenerative disorders. However, whether the composition and diversity of the gut microbiota are altered in tauopathies remains largely unknown. This study was aimed to examine the diversity and composition of the gut microbiota in tauopathies, as well as the correlation with pathological changes in the brain. We collected fecal samples from 32 P301L tau transgenic mice and 32 age- and gender-matched littermate mice at different ages. The 16S ribosomal RNA sequencing technique was used to analyze the microbiota composition in feces. Brain tau pathology levels were measured by immunohistochemistry. The diversity and composition of the gut microbiota significantly changed with aging. At the phylum level, the relative abundance of Bacteroidetes was increased, while Firmicutes were decreased in P301L mice compared with that in Wt mice after 3 months of age. In addition, Actinobacteria was decreased in P301L mice at 3 and 6 months of age, meanwhile Tenericutes was decreased in P301L mice at 10 months of age. Moreover, several specific macrobiota were highly associated with the levels of AT8-tau or pT231-tau protein in the brain. Our findings suggest that gut microbiota changed with aging, as well as in the tauopathy mice model. Modulation of the gut microbiota may be a potential strategy for treatment of tauopathy.
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Modelos Animais de Doenças , Microbioma Gastrointestinal/genética , Tauopatias/genética , Tauopatias/microbiologia , Animais , Humanos , Camundongos , Camundongos Transgênicos , Fatores de TempoRESUMO
C/EBPα is an essential transcription factor involved in regulating the expression or function of certain cell-cycle regulators, including in breast cancer cells. Although protein arginine methyltransferases have been shown to play oncogenic roles in a variety of cancers, little is known about the role of arginine methylation in regulating the antiproliferation activity of C/EBPα. Here, we report that the protein arginine methyltransferase 1 (PRMT1) is overexpressed in human breast cancer and that elevated PRMT1 correlates with cancer malignancy. RNA-sequencing analysis revealed that knockdown of PRMT1 in breast cancer cells is accompanied by a decrease in the expression of pro-proliferative genes, including cyclin D1. Furthermore, tandem affinity purification followed by mass spectrometry identified PRMT1 as a component of the C/EBPα complex. C/EBPα associated with and was methylated by PRMT1 at three arginine residues (R35, R156, and R165). PRMT1-dependent methylation of C/EBPα promoted the expression of cyclin D1 by blocking the interaction between C/EBPα and its corepressor HDAC3, which resulted in rapid growth of tumor cells during the pathogenesis of breast cancer. Inhibition of PRMT1 significantly impeded the growth of cancer cells from patients with triple-negative breast cancer. This evidence that PRMT1 mediates C/EBPα methylation sheds light on a novel pathway and potential therapeutic target in breast cancer. SIGNIFICANCE: This study provides novel mechanistic insight of the role of the arginine methyltransferase PRMT1 in breast cancer pathogenesis.
Assuntos
Neoplasias da Mama/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/metabolismo , Animais , Arginina/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Proteínas Estimuladoras de Ligação a CCAAT/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Ciclina D1/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Histona Desacetilases/metabolismo , Humanos , Metilação , Camundongos Endogâmicos BALB C , Proteína-Arginina N-Metiltransferases/genética , Proteínas Repressoras/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Exogenous discharge can positively promote nerve repair. We, therefore, hypothesized that endogenous discharges may have similar effects. The phrenic nerve and intercostal nerve, controlled by the respiratory center, can emit regular nerve impulses; therefore these endogenous automatically discharging nerves might promote nerve regeneration. Action potential discharge patterns were examined in the diaphragm, external intercostal and latissimus dorsi muscles of rats. The phrenic and intercostal nerves showed rhythmic clusters of discharge, which were consistent with breathing frequency. From the first to the third intercostal nerves, spontaneous discharge amplitude was gradually increased. There was no obvious rhythmic discharge in the thoracodorsal nerve. Four animal groups were performed in rats as the musculocutaneous nerve cut and repaired was bland control. The other three groups were followed by a side-to-side anastomosis with the phrenic nerve, intercostal nerve and thoracodorsal nerve. Compound muscle action potentials in the biceps muscle innervated by the musculocutaneous nerve were recorded with electrodes. The tetanic forces of ipsilateral and contralateral biceps muscles were detected by a force displacement transducer. Wet muscle weight recovery rate was measured and pathological changes were observed using hematoxylin-eosin staining. The number of nerve fibers was observed using toluidine blue staining and changes in nerve ultrastructure were observed using transmission electron microscopy. The compound muscle action potential amplitude was significantly higher at 1 month after surgery in phrenic and intercostal nerve groups compared with the thoracodorsal nerve and blank control groups. The recovery rate of tetanic tension and wet weight of the right biceps were significantly lower at 2 months after surgery in the phrenic nerve, intercostal nerve, and thoracodorsal nerve groups compared with the negative control group. The number of myelinated axons distal to the coaptation site of the musculocutaneous nerve at 1 month after surgery was significantly higher in phrenic and intercostal nerve groups than in thoracodorsal nerve and negative control groups. These results indicate that endogenous autonomic discharge from phrenic and intercostal nerves can promote nerve regeneration in early stages after brachial plexus injury.
RESUMO
OBJECTIVE: To investigate the clinical effect of modified Snodgrass surgical technique in the treatment of hypospadias. METHODS: We retrospectively analyzed the clinical data about 212 cases of hypospadias treated by urethroplasty from January 2008 to October 2016, 94 with the modified Snodgrass technique, namely with a silk line in addition to the urethral suture to make easier postoperative removal of the suture (group A), and the other 118 with the conventional Snodgrass technique (group B). The urethral suture was removed at 10 days after surgery for the patients in group A. We compared the success rate of surgery and incidence of postoperative complications between the two groups. RESULTS: Compared with group B, group A showed a significantly higher success rate of surgery (81.36% vs 91.49%, P <0.05) but lower incidence rates of postoperative incisional infection (12.71% vs 4.26%, P <0.05) and urinary fistula (16.10% vs 6.38%, P <0.05). No statistically significant difference was found in the incidence of urethral stenosis between the two groups (2.54% vs 2.13%, P >0.05). CONCLUSIONS: The modified Snodgrass technique can improve the success rate of surgery and reduce the incidence rates of incisional infection and urinary fistula, which deserves wide clinical application.