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A nonsense mutation in cereblon (CRBN) causes autosomal recessive nonsyndromic mental retardation. Cereblon is a substrate receptor for the Cullin-RING E3 ligase complex and couples the ubiquitin ligase to specific ubiquitination targets. The CRBN nonsense mutation (R419X) results in a protein lacking 24 amino acids at its C terminus. Although this mutation has been linked to mild mental retardation, the mechanism by which the mutation affects CRBN function is unknown. Here, we used biochemical and mass spectrometric approaches to explore the function of this mutant. We show that the protein retains its ability to assemble into a Cullin-RING E3 ligase complex and catalyzes the ubiquitination of CRBN-target proteins. However, we find that this mutant exhibits markedly increased levels of autoubiquitination and is more readily degraded by the proteasome than the wild type protein. We also show that the level of the mutant protein can be restored by a treatment of cells with a clinically utilized proteasome inhibitor, suggesting that this agent may be useful for the treatment of mental retardation associated with the CRBN R419X mutation. These data demonstrate that enhanced autoubiquitination and degradation account for the defect in CRBN activity that leads to mental retardation. [ABSTRACT FROM AUTHOR]

Background: Grain protein content (GPC) is an important quality determinant for barley used as malt, feed as well as food. It is controlled by a complex genetic system. GPC differs greatly among barley genotypes and is also variable across different environments. It is imperative to understand the genetic control of barley GPC and identify the genotypes with less variation under the different environments. Results: In this study, 59 cultivated and 99 Tibetan wild barley genotypes were used for a genome-wide association study (GWAS) and a multi-platform candidate gene-based association analysis, in order to identify the molecular markers associated with GPC. Tibetan wild barley had higher GPC than cultivated barley. The significant correlation between GPC and diastatic power (DP), and malt extract confirmed the importance of GPC in determining malt quality. Diversity arrays technology (DArT) markers associated with barley GPC were detected by GWAS. In addition, GWAS revealed two HvNAM genes as the candidate genes controlling GPC. No association was detected between HvNAM1 polymorphism and GPC, while a single nucleotide polymorphism (SNP) (798, P < 0.01), located within the second intron of HvNAM2, was associated with GPC. There was a significant correlation between haplotypes of HvNAM1, HvNAM2 and GPC in barley. Conclusions: The GWAS and candidate gene based-association study may be effectively used to determine the genetic variation of GPC in barley. The DArT markers and the polymorphism of HvNAM genes identified in this study are useful in developing high quality barley cultivars in the future. HvNAM genes could play a role in controlling barley GPC. [ABSTRACT FROM AUTHOR]

The proliferation of all nontransformed adherent cells is dependent upon the development of mechanical tension within the cell; however, little is known about the mechanisms by which signals regulated by mechanical tension are integrated with those regulated by growth factors. We show here that Skp2, a component of a ubiquitin ligase complex that mediates the degradation of several proteins that inhibit proliferation, is upregulated when increased mechanical tension develops in intact smooth muscle and that its upregulation is critical for the smooth muscle proliferative response to increased mechanical tension. Notably, whereas growth factors regulate Skp2 at the level of protein stability, we found that mechanical tension regulates Skp2 at the transcriptional level. Importantly, we demonstrate that the calcium-regulated transcription factor NFATc1 is a critical mediator of the effect of increased mechanical tension on Skp2 transcription. These findings identify Skp2 as a node at which signals from mechanical tension and growth factors are integrated to regulate proliferation, and they define calcium-NFAT-Skp2 signaling as a critical pathway in the mechanoregulation of proliferation. [ABSTRACT FROM AUTHOR]

Introduction. Clinical neurophysiology is the study of the human nervous system through the recording of bioelectrical activity. In the realm of male sexual functioning, this includes using electrophysiologic techniques to study the nerves subserving erection, emission, ejaculation, and orgasm. Aim. To introduce the reader to the principles of clinical neurophysiology as they relate to the male sexual response, particularly erection. Methods. We review the pertinent autonomic neuroanatomy and neurophysiology of reflexes relevant to the male sexual response, as well as summarize the genital electrodiagnostic tests that are being used to interrogate the autonomic innervation pertinent to male sexual functioning. Conclusions. The male sexual response is a coordinated series of interactions between the somatic and the autonomic nervous systems. Measurement of the autonomically mediated portions of the sexual reflexes is of great clinical interest, particularly in relation to erection. Advances in clinical electrodiagnostics now allow for consistent recording of evoked and spontaneous intrapenile electrical activity. However, before broad and widespread use of these techniques is possible, more investigations are needed. Yang CC, and Jiang X. Clinical autonomic neurophysiology and the male sexual response: An overview. J Sex Med 2009;6(suppl 3):221–228. [ABSTRACT FROM AUTHOR]

Corpus cavernosum electromyography (CC-EMG) has been intensively studied as a potential clinical tool for evaluating the function of the cavernous smooth muscle and its autonomic innervations since 1989. Both basic and clinical studies have shown promising results. However, its application as a diagnostic tool with clinical relevance was hindered by insufficient knowledge of cavernous smooth muscle electrophysiology and a series of technical and practical difficulties. Recently, major progress has been made to overcome these difficulties. Multichannel monopolar recording method has been proved to be superior to traditional one or two-channel bipolar recording. Correlation techniques have been applied as a comprehensive, objective and easy-to-use method to analyze CC-EMG recordings. Using these newly developed techniques, CC-EMG has been demonstrated to be discriminative in erectile dysfunction patients with conditions that are associated with cavernous smooth muscle degeneration and/or autonomic neuropathy from men with normal erectile function. However, before CC-EMG can be used as a robust method for erectile dysfunction-diagnostics, some basic and clinical issues are still to be solved. This review presents an overview of the latest advances in CC-EMG studies, mainly focusing on the clinical application of this method as a diagnostic tool. Furthermore, the background knowledge of cavernous electrophysiology, the problems to be overcome and future perspectives are also discussed. [ABSTRACT FROM AUTHOR]

A widely tunable single-longitudinal-mode (SLM) ytterbium-doped fiber laser is experimentally demonstrated, which is achieved by combining a fiber Lyot filter and a saturable absorber in a ring cavity. Stable SLM operation from 1045 nm to 1076 nm is obtained by properly adjusting the polarization state. The output power reaches 7.5 dBm with a fluctuation of less than 2 dB. The optical signal-to-noise ratio is 42.5 dB with a fluctuation of less than 6 dB in this wavelength range. [ABSTRACT FROM AUTHOR]

Context • The Da-yuan-yin (DYY) decoction is a classical prescription of traditional Chinese medicine that has antipyretic and anti-inflammatory effects. Network Pharmacology (NP) is an emerging discipline based on system-biology theory and biosystem network analysis that researchers can use to predict drug-action targets and mechanisms. Objective • The study intended to use NP evaluate the protective effects of the fifth eluting fraction of the supernatant of the DYY decoction (DYY-5) for mice induced with acute lung injury (ALI) using lipopolysaccharide (LPS) and to explore DYY-5’s mechanisms. Design • The research team performed an animal study. Setting • The study took place at the College of Pharmaceutical Science at Soochow University in Suzhou, China. Animals • The animals were 42 male Balb/c mice, about 20 to 25 g in weight. Intervention • The research team: instilled 2 mg/kg of LPS intratracheally (i.t.) to induce ALI. The team divided the mice into seven groups of six mice: (1) a control group; (2) a negative control group—the DYY-5 group with mice treated only with a high dosage, 60 mg/kg, of DYY-5 to investigate the effects of DYY-5 on normal mice; (3) the positive control group, the LPS group, with induced ALI but no treatments; (4) the LPS+60 mg/kg-DYY-5 group with induced ALI treated with a high dosage of DYY-5; (5) the LPS+30 mg/kg-DYY-5 group with induced ALI treated with a medium dosage of DYY-5; (6) the LPS+15 mg/kg-DYY-5 group with induced ALI treated with a low dosage of DYY-5; and (7) a reference drug control group, the LPS+DXM group, with induced ALI treated with 5 mg/kg of dexamethasone (DXM). Outcome Measures • The research team: (1) determined the chemical components of DYY; (2) identified the anticomplementary activities of DYY-5; (3) took lung specimens, serum, and bronchoalveolar lavage fluid (BALF) from the mice for histopathological examination, Western blot, and biochemical analysis; (4) measured total protein concentrations and lung W/D ratios; (5) measured the expressions of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) messenger RNA (mRNA) using quantitative real-time polymerase chain reaction (PCR); (6) measured the levels of pro-inflammatory and anti-inflammatory factors, the activity of myeloperoxidase (MPO) and superoxide dismutase (SOD), and the levels of complements, including complements 3 (C3), C3c, C5a, C5aR1, and C5b-9, using kits; (7) analyzed the levels of nuclear factor)kappa B (NF-κB) and IkB kinase (IKK) using Western blot; and (8) used network pharmacology (NP) to predict DYY-5’s mechanisms and potential targets. Results • The study’s results were consistent with the NP analysis, which reflected the multitarget and multipathway characteristics of DYY-5 in alleviating ALI. The LPS+30 mg/ kg-DYY-5 group had significantly lower lung wet-to-dry (W/D) ratios and total protein concentrations in BALF than the LPS group did, with P < .01 and P < .0001, respectively as did the LPS+60 mg/kg-DYY-5 group (both P < .0001). The 60 mg/kg of DYY-5 compared to the LPS group: (1) regulated the levels tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), and interleukin-1 beta (IL-1β), with all P < .0001, anti-inflammatory factors—IL-4 (P < .05), IL-10 (P < .001), and IL-13 (P < .001); (2) increased the activity of SOD (P < .0001) and decreased the activity of MPO (P < .0001) and the expressions of iNOS and COX-2 mRNA (both P < .01); (3) blocked the activation of NF-κB and IKK; and (4) alleviated the pathological changes in the lung tissue, by reducing the depositions of C3c and decreasing the levels of C3, C5a and C5aR1 (all P<.0001), C5b-9 (P<.001) and C3c (P<.01) in serum. Conclusions • The protective effects of DYY-5 on ALI were related to antioxidation, anti-complementary activities, and regulation of inflammatory factors through the IKK/NF-κB signal pathway. DYY-5 may be useful as a potential therapeutic agent for treating ALI in clinics. ( [ABSTRACT FROM AUTHOR]

Combined with the occurrence characteristics of China’s low permeability coal seam and the advantages and disadvantages of various permeability enhancement technologies, the technical methods to improve the permeability of coal seam are classified and compared, and the technology, equipment, application effect, existing problems and defects and applicable conditions of each permeability enhancement method are systematically sorted out. The development trend of permeability enhancement technology is prospected, and it is pointed out that permeability enhancement technology will work in combination with various permeability enhancement methods, and permeability enhancement equipment will develop towards intelligent and unmanned direction.

Background: Nitric oxide (NO) plays a critical role in the recovery stage, in maintaining a large blood flow in skeletal muscle and in promoting recovery after exercise. Research question: This study observed the NO level, NOS activity and the expression of NOS in rat skeletal muscle under normoxic and hypoxic training conditions. Type of study: Randomised controlled study. Methods: Sixty-four male Sprague-Dawley rats were randomly divided into normoxic control group, two-week training, four-week training, six-week training groups; hypoxic control group, two-week hypoxic training, four-week hypoxic training, six-week hypoxic training groups. The classic Griess method was used to test nitric oxide in the homogenate of skeletal muscle. Moreover, methods such as RT-PCR, western blot, etc. were utilised to test the change of the all types of nitric oxide synthase expression. Results: The results showed that the NO content of rat skeletal muscle was significantly increased in two, four, and six-week training subgroups compared with the control group under normoxic conditions; NO content increased in the four-weeks and six-weeks hypoxic training group compared with the hypoxic control group (p <0.05, p <0.01). Under hypoxic conditions, with increasing exercise time, the cNOS activity and the expression cNOS protein was significant different between the training group and the control group, while there was no change in iNOS expression. Conclusions: The data in this study suggested that the hypoxic exercise may promote increases in the NOS and NO levels, counteract the blood vessel contractile effect of hypoxia, and improve the relaxed tone of blood vessels. [ABSTRACT FROM AUTHOR]

Chronic inflammation is associated with multiple human disorders, such as rheumatoid arthritis, metabolic diseases, and neurodegenerative diseases. Therefore, alleviation of inflammation induced by environmental stimuli is important for disease prevention or treatment. Cereblon (CRBN) functions as a substrate receptor of the cullin-4 RING E3 ligase to mediate protein ubiquitination and degradation. Although it has been reported that CRBN reduces the inflammatory response through its nonenzymatic function, its role as a substrate receptor of the E3 ligase is not explored in mediating this process. Here we used a quantitative proteomics approach to find that the major component of the activator protein 1 (AP-1) complex, c-Jun, is significantly down-regulated upon CRBN expression. Biochemical approaches further discover that CRBN interacts and partially colocalizes with c-Jun and promotes the formation of Lys48-linked polyubiquitin chains on c-Jun, enhancing c-Jun degradation. We further reveal that CRBN attenuates the transcriptional activity of the AP-1 complex and reduces the mRNA expression and protein level of several pro-inflammatory cytokines. Moreover, flow cytometry analyses show that CRBN attenuates lipopolysaccharide-induced apoptosis in differentiated THP-1 cells. Through genetic manipulation and pharmacological inhibition, we uncover a new molecular mechanism by which CRBN regulates the inflammatory response and apoptosis induced by lipopolysaccharide. Our work and previous studies demonstrate that CRBN suppresses the inflammatory response by promoting or inhibiting the ubiquitination of two key molecules at different levels of the inflammatory cascade through its enzymatic function as a substrate receptor and its nonenzymatic function as a protein binding partner. [ABSTRACT FROM AUTHOR]