Alpha (1,2)-Fucosyltransferase M307A Polymorphism Improves Piglet Survival

To confirm the beneficial effects of alpha (1,2)-fucosyltransferase (FUT1) M307 ^A on piglet survival on commercial farms, we performed PCR-RFLP analysis of FUT1 M307 in successfully marketed (n = 245) and disease affected/deceased pigs during weaning (n = 252) at a commercial farm. We also evaluated the FUT1 genotypes of 190 healthy pigs from three different genetic backgrounds. The distribution of genotypes differed between the successfully marketed and disease affected/deceased pig groups. The frequency of the A allele, associated with resistance to edema and post-weaning diarrhea, was higher in the post-weaning survival group (0.21) than in the non-survival group (0.16, P < 0.05). The odds ratio for piglet survival between AA and GG genotypes was 1.98; thus, piglet survival for individuals with the AA genotype was almost two-fold greater than for GG individuals. The FUT1 gene polymorphism can be used as an effective marker for selection programs to improve post-weaning piglet survival.     

外源NO对不同UV-B辐射天数处理的小麦叶片总蛋白的影响

研究外源NO对不同UV-B辐射天数处理的小麦叶片总蛋白的影响.采用蒸馏水和0.1 mmol/L 硝普钠（SNP,一种NO供体）浸种24 h,试验设置不同的处理组：CK、CK＋B、SNP、SNP＋B.待幼苗生长7天后取其叶片进行总蛋白的提取及SDS-PAGE凝胶图像的分析.不同处理对叶片总蛋白含量、电泳图谱及电泳条带数目的影响不同;外源NO能显著增加不同UV-B处理天数下小麦叶片总蛋白的含量,且SNP和SNP＋B处理组的电泳条带均较CK和CK＋B处理组的电泳条带变宽且颜色变深.外源NO能显著增加UV-B辐射下小麦叶片的总蛋白含量.同时,不同处理组电泳条带数目的变化反应出一些蛋白的降解和合成,最终也体现了不同处理组蛋白含量的变化.     

Tonotopic reorganization and spontaneous firing in inferior colliculus during both short and long recovery periods after noise overexposure

Background

Noise induced injury of the cochlea causes shifts in activation thresholds and changes of frequency response in the inferior colliculus (IC). Noise overexposure also induces pathological changes in the cochlea, and is highly correlated to hearing loss. However, the underlying mechanism has not been fully elucidated. In this study, we hypothesized that overexposure to noise induces substantial electrophysiological changes in the IC of guinea pigs.

Results

During the noise exposure experiment, the animals were undergoing a bilateral exposure to noise. Additionally, various techniques were employed including confocal microscopy for the detection of cochlea hair cells and single neuron recording for spontaneous firing activity measurement. There were alterations among three types of frequency response area (FRA) from sound pressure levels, including V-, M-, and N-types. Our results indicate that overexposure to noise generates different patterns in the FRAs. Following a short recovery (one day after the noise treatment), the percentage of V-type FRAs considerably decreased, whereas the percentage of M-types increased. This was often caused by a notch in the frequency response that occurred at 4 kHz (noise frequency). Following a long recovery from noise exposure (11–21 days), the percentage of V-types resumed to a normal level, but the portion of M-types remained high. Interestingly, the spontaneous firing in the IC was enhanced in both short and long recovery groups.

Conclusion

Our data suggest that noise overexposure changes the pattern of the FRAs and stimulates spontaneous firing in the IC in a unique way, which may likely relate to the mechanism of tinnitus.     

MicroRNA-409-3p inhibits migration and invasion of bladder cancer cells via targeting c-Met

There is increasing evidence suggesting that dysregulation of certain microRNAs (miRNAs) may contribute to tumor progression and metastasis. Previous studies have shown that miR-409-3p is dysregulated in some malignancies, but its role in bladder cancer is still unknown. Here, we find that miR-409-3p is down-regulated in human bladder cancer tissues and cell lines. Enforced expression of miR-409-3p in bladder cancer cells significantly reduced their migration and invasion without affecting cell viability. Bioinformatics analysis identified the pro-metastatic gene c-Met as a potential miR-409-3p target. Further studies indicated that miR-409-3p suppressed the expression of c-Met by binding to its 3′-untranslated region. Silencing of c-Met by small interfering RNAs phenocopied the effects of miR-409-3p overexpression, whereas restoration of c-Met in bladder cancer cells bladder cancer cells overexpressing miR-409-3p, partially reversed the suppressive effects of miR-409-3p. We further showed that MMP2 and MMP9 may be downstream effector proteins of miR-409-3p. These findings indicate that miR-409-3p could be a potential tumor suppressor in bladder cancer.     

HCV-specific interleukin-21+CD4+ T cells responses associated with viral control through the modulation of HCV-specific CD8+ T cells function in chronic hepatitis C patients

Interleukin-21 (IL-21)+CD4+ T cells are involved in the immune response against hepatitis B virus (HBV) by secreting IL-21. However, the role of IL-21+CD4+ T cells in the immune response against chronic hepatitis C (CHC) virus infection is poorly understood. This study aimed to investigate the role of IL-21+CD4+ T cells in CHC patients and the potential mechanisms. The study subjects included nineteen CHC patients who were grouped by viral load (low, < 10⁶ RNA copies/ml, n = 8; high, > 10⁶ RNA copies/ml, n = 11). The peripheral frequency of HCV-specific IL-21+CD4+ T cells was higher in the low viral load group and was negatively correlated with the serum HCV RNA viral load in all CHC patients. Meanwhile, IL-21+ cells accumulated in the liver in the low viral load group. In vitro, IL-21 treatment increased the expression of proliferation markers and cytolytic molecules on HCV-specific CD8+ T cells. In summary, these findings suggest that HCV-specific IL-21+CD4+ T cells might contribute to HCV control by rescuing HCV-specific CD8+ T cells in CHC patients.     

Differential requirement of Oryza sativa RAR1 in immune receptor-mediated resistance of rice to Magnaporthe oryzae

The required for Mla12 resistance (RAR1) protein is essential for the plant immune response. In rice, a model monocot species, the function of Oryza sativa RAR1 (OsRAR1) has been little explored. In our current study, we characterized the response of a rice osrar1 T-DNA insertion mutant to infection by Magnaporthe oryzae, the causal agent of rice blast disease. osrar1 mutants displayed reduced resistance compared with wild type rice when inoculated with the normally virulent M. oryzae isolate PO6-6, indicating that OsRAR1 is required for an immune response to this pathogen. We also investigated the function of OsRAR1 in the resistance mechanism mediated by the immune receptor genes Pib and Pi5 that encode nucleotide binding-leucine rich repeat (NB-LRR) proteins. We inoculated progeny from Pib/osrar1 and Pi5/osrar1 heterozygous plants with the avirulent M. oryzae isolates, race 007 and PO6-6, respectively. We found that only Pib-mediated resistance was compromised by the osrar1 mutation and that the introduction of the OsRAR1 cDNA into Pib/osrar1 rescued Pib-mediated resistance. These results indicate that OsRAR1 is required for Pib-mediated resistance but not Pi5-mediated resistance to M. oryzae.     

A depth-dependent model of the pericellular microenvironment of chondrocytes in articular cartilage

Experimental studies suggest that the magnitude of chondrocyte deformation is much smaller than expected based on the material properties of extracellular matrix (ECM) and cells, and that this result could be explained by a structural unit, the chondron, that is thought to protect chondrocytes from large deformations in situ. We extended an existing numerical model of chondrocyte, ECM and pericellular matrix (PCM) to include depth-dependent structural information. Our results suggest that superficial zone chondrocytes, which lack a pericellular capsule (PC), are relatively stiff, and therefore are protected from excessive deformations, whereas middle and deep zone chondrocytes are softer but are protected by the PC that limits cell deformations in these regions. We conclude that cell deformations sensitively depend on the immediate structural environment of the PCM in a depth-dependent manner, and that the functional stiffness of chondrocytes in situ is much larger than experiments on isolated cells would suggest.     

Ca2+-Dependent Protein Kinase11 and 24 Modulate the Activity of the Inward Rectifying K+ Channels in Arabidopsis Pollen Tubes

Potassium (K⁺) influx into pollen tubes via K⁺ transporters is essential for pollen tube growth; however, the mechanism by which K⁺ transporters are regulated in pollen tubes remains unknown. Here, we report that Arabidopsis thaliana Ca²⁺-dependent protein kinase11 (CPK11) and CPK24 are involved in Ca²⁺-dependent regulation of the inward K⁺ (K+_in) channels in pollen tubes. Using patch-clamp analysis, we demonstrated that K+_in currents of pollen tube protoplasts were inhibited by elevated [Ca²⁺]_cyt. However, disruption of CPK11 or CPK24 completely impaired the Ca²⁺-dependent inhibition of K+_in currents and enhanced pollen tube growth. Moreover, the cpk11 cpk24 double mutant exhibited similar phenotypes as the corresponding single mutants, suggesting that these two CDPKs function in the same signaling pathway. Bimolecular fluorescence complementation and coimmunoprecipitation experiments showed that CPK11 could interact with CPK24 in vivo. Furthermore, CPK11 phosphorylated the N terminus of CPK24 in vitro, suggesting that these two CDPKs work together as part of a kinase cascade. Electrophysiological assays demonstrated that the Shaker pollen K+_in channel is the main contributor to pollen tube K+_in currents and acts as the downstream target of the CPK11-CPK24 pathway. We conclude that CPK11 and CPK24 together mediate the Ca²⁺-dependent inhibition of K+_in channels and participate in the regulation of pollen tube growth in Arabidopsis.