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Straw return is considered an effective way to improve the soil organic carbon (SOC) content of farmland. Most studies have suggested that a straw application increases the SOC content; however, some suggest that a straw application reduces the SOC content when used in combination with mineral fertilisation. Therefore, a meta-analysis of the effect of a straw application on the SOC change is needed. This study comprises a meta-analysis of 115 observations from 65 research articles worldwide. Straw applications can significantly increase the proportion of the SOC in the soil. Straw applications caused a significant microbial biomass carbon (MBC) increase in tropical and warm climatic zones. The MBC increase was higher than the SOC increase. For agriculture, the most important soil functions are the maintenance of the crop productivity, the nutrient and water transformation, the biological flora and activity, and the maintenance of the microbial abundance and activity. These functions should be prioritised in order to maintain the SOC function and services. Straw applications should not be excessive, especially when combined with mineral fertilisation, in order to avoid the loss of carbon from the straw in the form of greenhouse gases. A large amount of unused fertiliser also leads to a series of environmental problems. [ABSTRACT FROM AUTHOR]

L-carnitine (LC) is required for transporting long-chain fatty acids into the mitochondria, where β-oxidation takes place, and it works as an antioxidant molecule against reactive oxygen species. This study evaluated the effects of LC on the growth and antioxidant function of Amur minnow (Phoxinus lagowskii Dybowskii). Five isonitrogenous (380.4 g/kg) and isoenergetic (17.63 MJ/kg) diets were supplemented with five LC levels: control level (0 mg/kg) and treatment levels (50, 400, 750, or 1,100 mg/kg) were fed to fish (18.19 ± 0.56 g) for 120 days. The results showed that the growth performance of fish fed a diet containing 400 mg/kg of LC was significantly higher than that of the control and those fed other LC level treatments. Similarly, the 400 mg/kg treatment had the best feed efficiency. Further, the levels of total antioxidant capacity and total glutathione in the serum and hepatopancreas of fish fed a diet containing 750 mg/kg of LC were significantly increased; however, malondialdehyde levels were significantly reduced compared to those of the control group. The activities of antioxidant enzymes of 750 mg/kg treatments in the serum and hepatopancreas were significantly higher than those of the control group, including total superoxide dismutase, catalase, glutathione peroxidase and gamma-glutamylcysteine synthetase. Finally, 750 mg/kg treatment significantly upregulated the mRNA relative expression of antioxidant enzymes and nuclear factor erythroid-2-related factor 2 and inhibited the mRNA level of kelch-like ECH-associated protein 1 in the hepatopancreas. In conclusion, the dietary LC level of 400-750 mg/kg could improve the growth performance, feed utilization and antioxidant defense system of Amur minnow under the culture conditions. [ABSTRACT FROM AUTHOR]

The epidemiological researches show that the mutations of GJB2, mitochondrial 12S rRNA, and SLC26A4 genes have played an important role in the hearing loss. This study aims to investigate the mutation spectrum of GJB2, mitochondrial 12S rRNA, and SLC26A4 genes of Han Chinese, Hui people, and Uyghur ethnicities in sensorineural hearing loss (SNHL) patients in northwest of China. Mutational analyses in the three genes were brought by direct sequencing and each fragment was analyzed using an ABI 3730 DNA Sequencer. The mutation frequencies for the three HL causative genes were 34.05% in Han Chinese participants, 27.47% in Hui people, and 14.44% in Uyghur participants, respectively. The prevalence of GJB2 mutations was 13.7%, 11.4%, and 11.4% n Han Chinese, Hui people, and Uyghur participants (X2= 10.2, P < 0.05), respectively. The prevalence of mtDNA 12S rRNA A1555G homozygous mutations was 6.05%, 3.27%, and 1.44% in Han Chinese, Hui people, and Uyghur participants (X2= 13.9, P < 0.05), respectively. The prevalence of SLC26A4 mutations was 14.3%, 12.8%, and 1.6% in Han Chinese, Hui people, and Uyghur participants, respectively. In summary, we find that Uyghur and Hui SNHL individuals vary significantly from Han Chinese patients in three causative HL genes'' mutational spectrum, especially for Uyghur. [ABSTRACT FROM AUTHOR]

Background: Plasma cells constitute the majority of tumor cells in multiple myeloma (MM) but lack the potential for sustained clonogenic growth. In contrast, clonotypic B cells can engraft and recapitulate disease in immunodeficient mice suggesting they serve as the MM cancer stem cell (CSC). These tumor initiating B cells also share functional features with normal stem cells such as drug resistance and self-renewal potential. Therefore, the cellular processes that regulate normal stem cells may serve as therapeutic targets in MM. Telomerase activity is required for the maintenance of normal adult stem cells, and we examined the activity of the telomerase inhibitor imetelstat against MM CSC. Moreover, we carried out both long and short-term inhibition studies to examine telomere length-dependent and independent activities. Methodology/Principal Findings: Human MM CSC were isolated from cell lines and primary clinical specimens and treated with imetelstat, a specific inhibitor of the reverse transcriptase activity of telomerase. Two weeks of exposure to imetelstat resulted in a significant reduction in telomere length and the inhibition of clonogenic MM growth both in vitro and in vivo. In addition to these relatively long-term effects, 72 hours of imetelstat treatment inhibited clonogenic growth that was associated with MM CSC differentiation based on expression of the plasma cell antigen CD138 and the stem cell marker aldehyde dehydrogenase. Short-term treatment of MM CSC also decreased the expression of genes typically expressed by stem cells (OCT¾, SOX2, NANOG, and BMI1) as revealed by quantitative real-time PCR. Conclusions: Telomerase activity regulates the clonogenic growth of MM CSC. Moreover, reductions in MM growth following both long and short-term telomerase inhibition suggest that it impacts CSC through telomere length-dependent and independent mechanisms. [ABSTRACT FROM AUTHOR]

The cancer stem cell hypothesis suggests that malignant growth depends on a subset of tumor cells with stem cell-like properties of self-renewal. Because hedgehog (Hh) signaling regulates progenitor cell fate in normal development and homeostasis, aberrant pathway activation might be involved in the maintenance of such a population in cancer. Indeed, mutational activation of the Hh pathway is associated with medulloblastoma and basal cell carcinoma; pathway activity is also critical for growth of other tumors lacking such mutations, although the mechanism of pathway activation is poorly understood. Here we study the role and mechanism of Hh pathway activation in multiple myeloma (MM), a malignancy with a well defined stem cell compartment. In this model, rare malignant progenitors capable of clonal expansion resemble B cells, whereas the much larger tumor cell population manifests a differentiated plasma cell phenotype that pathologically defines the disease. We show that the subset of MM cells that manifests Hh pathway activity is markedly concentrated within the tumor stem cell compartment. The Hh ligand promotes expansion of MM stem cells without differentiation, whereas the Hh pathway blockade, while having little or no effect on malignant plasma cell growth, markedly inhibits clonal expansion accompanied by terminal differentiation of purified IVINI stem cells. These data reveal that Hh pathway activation is heterogeneous across the spectrum of MM tumor stem cells and their more differentiated progeny. The potential existence of similar relationships in other adult cancers may have important biologic and clinical implications for the study of aberrant Hh signaling. [ABSTRACT FROM AUTHOR]

Disease relapse remains a major factor limiting the survival of cancer patients. In the plasma cell malignancy multiple myeloma (MM), nearly all patients ultimately succumb to disease relapse and progression despite new therapies that have improved remission rates. Tumor regrowth indicates that clonogenic growth potential is continually maintained, but the determinants of self-renewal in MM are not well understood. Normal stem cells are regulated by extrinsic niche factors, and the tumor microenvironment (TME) may similarly influence tumor cell clonogenic growth and self-renewal. Growth differentiation factor 15 (GDF15) is aberrantly secreted by bone marrow stromal cells (BMSCs) in MM. We found that GDF15 is produced by BMSCs after direct contact with plasma cells and enhances the tumor-initiating potential and self-renewal of MM cells in a protein kinase B- and SRY (sex-determining region Y)-box-dependent manner. Moreover, GDF15 induces the expansion of MM tumor-initiating cells (TICs), and changes in the serum levels of GDF15 were associated with changes in the frequency of clonogenic MM cells and the progression-free survival of MM patients. These findings demonstrate that GDF15 plays a critical role in mediating the interaction among mature tumor cells, the TME, and TICs, and strategies targeting GDF15 may affect long-term clinical outcomes in MM. [ABSTRACT FROM AUTHOR]

We report here the characterization of a large Chinese family with maternally transmitted aminoglycoside-induced and nonsyndromic deafness. In the absence of aminoglycosides, some matrilineal relatives in this family exhibited late-onset/progressive deafness, with a wide range of severity and age at onset. Notably, the average age at onset of deafness has changed from 55 years (generation II) to 10 years (generation IV). Clinical data reveal that the administration of aminoglycosides can induce or worsen deafness in matrilineal relatives. The age at the time of drug administration appears to be correlated with the severity of hearing loss experienced by affected individuals. Sequence analysis of mitochondrial DNA in this pedigree identified a homoplasmic C-to-T transition at position 1494 (C1494T) in the 12S rRNA gene. The C1494T mutation is expected to form a novel U1494-1555A base pair, which is in the same position as the C1494-1555G pair created by the deafness-associated A1555G mutation, at the highly conserved A site of 12S rRNA. Exposure to a high concentration of paromomycin or neomycin caused a variable but significant average increase in doubling time in lymphoblastoid cell lines derived from four symptomatic and two asymptomatic individuals in this family carrying the C1494T mutation when compared to four control cell lines. Furthermore, a significant decrease in the rate of total oxygen consumption was observed in the mutant cell lines. Thus, our data strongly support the idea that the A site of mitochondrial 12S rRNA is the primary target for aminoglycoside-induced deafness. These results also strongly suggest that the nuclear background plays a role in the aminoglycoside ototoxicity and in the development of the deafness phenotype associated with the C1494T mutation in the mitochondrial 12S rRNA gene. [ABSTRACT FROM AUTHOR]

Background: The molecular and genetic research showed the association between DFNA11 and mutations in MYO7A. This research aimed to identify a MYO7A mutation in a family with nonsyndromic autosomal dominant hearing loss. Methods: We have ascertained one large multigenerational Chinese family (Z029) with autosomal dominant late-onset progressive non-syndromic sensorineural hearing loss. Genome-wide linkage analysis of the family mapped the disease locus to the DFNA11 interval, where the MYO7A was considered as a candidate gene. Sequencing of the PCR products was carried out for each sample. One hundred and fifty one control subjects with normal hearing functions were also evaluated. Results: The pathogenic mutation (c.2011G>A) was identified in the family. This mutation co-segregated with hearing loss in this family. No mutation of MYO7A gene was found in the 151 controls. Conclusions: The missense mutation of MYO7A is identified in the family displaying the pedigree consistent with DFNA11. We not only examined the clinical and genetic characteristics of the family, but also provided a basis for genetic counseling. We also summarized and analyzed the phenotypes and genotypes of all DFNA11 families, four of nine are Chinese families, suggesting that MYO7A mutations are not rare. Therefore, we should pay more attention to Chinese patients. [ABSTRACT FROM AUTHOR]

Carnitine has vital roles in the endogenous metabolism of short chain fatty acids. It can protect and support gut microbial species, and some dietary fibers can reduce the available iron involved in the bioactivity of carnitine. There is also an antagonistic relationship between high microbial populations and carnitine bioavailability. This review shows the interactions between carnitine and gut microbial composition. It also elucidates the role of carnitine bacterial metabolism, mitochondrial function, fiber fermentability, and short chain fatty acids (SCFAs). [ABSTRACT FROM AUTHOR]

In field experiments, the effect of nitrogen application on 15N absorption and distribution of Longjing 31 and Kongyu 131 rice varieties was studied by 15N isotopic trace technique. The results showed that nitrogen absorbed by rice plant is the most in the early plant growth, and 15N accumulation of Longjing 31 grains are higher than Kongyu 131, but stem organ is the opposite; the reallocation and transfer efficiency of nitrogen absorbed by rice have an important role to the increasing of Longjing 31 output. [ABSTRACT FROM AUTHOR]

The major side-effects of high doses of salicylate include sensorial hearing loss and tinnitus. Although salicylate decreases cochlear output, it enhances the evoked potentials recorded from the central auditory system (CAS), suggesting an increase to sound sensitivity. However, the loudness change after salicylate administration has not yet been directly measured. In this study, we established an operant conditioning based behavioral task in rats and measured their loudness perception changes before and after high doses of salicylate injection (250mg/kg, i.p.). We found that high doses of salicylate induced a significant increase to loudness response in 40% of the rats (out of 20 rats), suggesting a hyperacusis behavior. In another 40% of rats, a rapid increase of loudness response was detected, suggesting loudness recruitment. The reaction time of the rats was also measured during the loudness tests before and after salicylate exposure. The reaction time level functions are highly correlated to the loudness response functions. Our studies confirmed that increased sound sensitivity, which is commonly seen in patients with tinnitus and hyperacusis, can be induced by high doses of salicylate. This loudness change induced by salicylate may be related with hypersensitivity in the CAS. [ABSTRACT FROM AUTHOR]

T-A cloning is the most commonly used molecular cloning technique in which T-vector is the core tool. T-vectors commonly used now are blue–white positive-selection vectors based on mechanism of α-complement of β-galactose of Escherichia coli. Disadvantages of these traditional T-vectors in application include insufficient positive rate and the existence of false-positive clones, which, especially the latter, makes screening of transformant clones via colony PCR necessary. In the present study, a novel T-vector, based on the strategy of inhibiting the growth of negative transformants by means of a lethal gene and innovative design of insertion site, was developed. The innovative design of the insertion site for PCR fragments not only guarantees complete blocking of the expression of the lethal gene when PCR fragments are inserted, but also eliminates the formation of false-positive clones. All (100%) of 20 randomly chosen grown colonies were shown to be positive via colony PCR in four separate experimental T-A clonings of PCR fragments with lengths between 219 and 2100 bp. The novel T-vector developed in the present study makes colony PCR screening unnecessary, because of its extremely high efficiency of negative transformant inhibition and the mechanism for elimination of false-positive clones. Temperature (42 °C)-dependent positive selection greatly simplifies the procedure and lowers the cost of T-A cloning. Furthermore, it is an ideal T-vector for constructing libraries of PCR-amplified DNA fragments such as SSH (suppressive subtraction hybridization) libraries because of its zero negative background performance. [ABSTRACT FROM AUTHOR]

Many DNA-hypermethylated cancer genes are occupied by the Polycomb (PcG) repressor complex in embryonic stem cells (ESCs). Their prevalence in the full spectrum of cancers, the exact context of chromatin involved, and their status in adult cell renewal systems are unknown. Using a genome-wide analysis, we demonstrate that 1/475% of hypermethylated genes are marked by PcG in the context of bivalent chromatin in both ESCs and adult stem/progenitor cells. A large number of these genes are key developmental regulators, and a subset, which we call the "DNA hypermethylation module," comprises a portion of the PcG target genes that are down-regulated in cancer. Genes with bivalent chromatin have a low, poised gene transcription state that has been shown to maintain stemness and self-renewal in normal stem cells. However, when DNA-hypermethylated in tumors, we find that these genes are further repressed. We also show that the methylation status of these genes can cluster important subtypes of colon and breast cancers. By evaluating the subsets of genes that are methylated in different cancers with consideration of their chromatin status in ESCs, we provide evidence that DNA hypermethylation preferentially targets the subset of PcG genes that are developmental regulators, and this may contribute to the stem-like state of cancer. Additionally, the capacity for global methylation profiling to cluster tumors by phenotype may have important implications for further refining tumor behavior patterns that may ultimately aid therapeutic interventions. [ABSTRACT FROM AUTHOR]