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2.
Am J Otolaryngol ; 45(5): 104358, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38754262

RESUMO

OBJECTIVE: This case series study investigated the outcomes of an innovative approach, ansa cervicalis nerve (ACN)-to-recurrent laryngeal nerve (RLN) low-tension anastomosis. METHODS: Patients who received laryngeal nerve anastomosis between May 2015 and September 2021 at the facility were enrolled. The inclusion criteria were patients with RLN dissection and anastomosis immediately during thyroid surgery. Exclusion criteria were cases with anastomosis other than cervical loop-RLN anastomosis or pronunciation recovery time > 6 months. Patients admitted before January 2020 were assigned to group A which underwent the conventional tension-free anastomosis, and patients admitted after January 2020 were group B and underwent the innovative low-tension anastomosis (Dong's method). RESULTS: A total of 13 patients were included, 11 patients received unilateral surgery, and 2 underwent bilateral surgery. For patients who underwent unilateral anastomosis, group B had a significantly higher percentage of normal pronunciation via GRBAS scale (83.3 % vs. 0 %, p = 0.015) and voice handicap index (66.7 % vs. 0 %, p = 0.002), and shorter recovery time in pronunciation (median: 1-day vs. 4 months, p = 0.001) than those in group A after surgery. CONCLUSIONS: ACNs-to-RLN low-tension anastomosis with a laryngeal segment ≤1 cm (Dong's method) significantly improves postoperative pronunciation and recovery time. The results provide clinicians with a new strategy for ACN -to-RLN anastomosis during thyroid surgery.

3.
Endocrine ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38502364

RESUMO

PURPOSE: This study aimed to evaluate the factors associated with bilateral papillary thyroid carcinoma (PTC) and lateral cervical lymph node metastasis (LLNM) in patients with suspicious unilateral PTC. METHODS: This study analyzed patients with suspicious unilateral PTC who were enrolled in a university hospital between 2016 and 2019 in Zhejiang, China. Using logistic regression, the study examined the factors associated with bilateral PTC and LLNM in demographic data, anthropometric measurements, lifestyle factors, medical history, preoperative diagnostic tests, and histopathological factors. RESULTS: A total of 256 patients, with a mean age of 49 years, were enrolled. Bilateral PTC was associated with multifocality (aOR: 5.069, 95% CI: 2.440-10.529, P < 0.001), and contralateral nodule in the upper (aOR: 9.073, 95% CI: 2.111-38.985, P = 0.003) and middle (aOR: 9.926, 95% CI: 2.683-36.717, P < 0.001). LLNM was positively associated with bilateral PTC (aOR, 4.283, 95% CI: 1.378-13.308, p = 0.012), male (aOR, 3.377, 95% CI: 1.205-9.461, P = 0.021), upper location of carcinoma (aOR, 3.311, 95% CI: 1.091-10.053, p = 0.035), and punctate echogenic foci (aOR, 3.309, 95% CI: 1.165-9.394, P = 0.025). Contralateral maximal nodule in the upper (aOR: 0.098, 95% CI: 0.015-0.628, p = 0.014), middle (aOR: 0.114, 95% CI: 0.033-0.522, p < 0.001), and lower (aOR, 0.028, 95% CI: 0.003-0.276, P = 0.002) location were inversely associated with LLNM. CONCLUSION: Upper and middle location of contralateral nodule and tumor multifocality predicted the risk bilateral PTC. Bilateral PTC, male, upper tumor location, punctate echogenic foci and contralateral nodule location in the entire lobes were independent predictors for LLNM.

4.
Nanomedicine (Lond) ; 18(27): 2039-2059, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-38131284

RESUMO

Aim: This study aimed to identify molecular markers associated with papillary thyroid cancer (PTC) and investigate the therapeutic potential of targeted nanoscale drugs. Materials & methods: We analyzed the effects of circICA1 and miR-486-3p on B-CPAP cells' proliferation, apoptosis, migration and invasion. The regulation of the miR-486-3p/SERPINA1 axis was explored using quantitative real-time reverse transcription PCR and western blot analyses for metastasis. In vivo, we evaluated the effects of hyperbranched polyamidoamine-RGD peptide/si-circICA1 on PTC growth and metastasis. Results: Enhanced miR-486-3p expression inhibits B-CPAP cells' proliferation and invasion. si-circICA1 delivered via hyperbranched polyamidoamine-RGD peptide nanoparticles shows potential for treating metastasis in PTC. Conclusion: This study identifies key molecular mechanisms underlying PTC invasiveness and suggests a promising therapeutic strategy for PTC using targeted nanoscale drugs.


Assuntos
MicroRNAs , Oligopeptídeos , Poliaminas , Neoplasias da Glândula Tireoide , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Invasividade Neoplásica/genética , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Câncer Papilífero da Tireoide/tratamento farmacológico , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Proliferação de Células , Movimento Celular , Regulação Neoplásica da Expressão Gênica , alfa 1-Antitripsina/metabolismo
5.
Life (Basel) ; 13(11)2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-38004304

RESUMO

Increasing concerns about hair loss affect people's quality of life. Recent studies have found that sympathetic nerves play a positive role in regulating hair follicle stem cell activity to promote hair growth. However, no study has investigated sympathetic innervation of transplanted follicles. Rat vibrissa follicles were extracted and implanted under the dorsal skin of BALB/c-nu/nu mice using one of two types of follicles: (1) intact follicles, where transplants included bulbs, and (2) upper follicles, where transplants excluded bulbs. Follicular samples were collected for hematoxylin and eosin staining, immunofluorescence staining for tyrosine hydroxylase (TH, a sympathetic marker) and enzyme-linked immunosorbent assays. At 37 days after implantation in both groups, follicles had entered anagen, with the growth of long hair shafts; tyrosine-hydroxylase-positive nerves were innervating follicles (1.45-fold); and norepinephrine concentrations (2.03-fold) were significantly increased compared to 5 days, but did not return to normal. We demonstrate the survival of intact and upper follicle xenografts and the partial restoration of sympathetic reinnervations of both transplanted follicles.

7.
bioRxiv ; 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37808851

RESUMO

Instead of employing telomerases to safeguard chromosome ends, dipteran species maintain their telomeres by transposition of telomeric-specific retrotransposons (TRs): in Drosophila , these are HeT-A , TART , and TAHRE . Previous studies have shown how these TRs create tandem repeats at chromosome ends, but the exact mechanism controlling TR transcription has remained unclear. Here we report the identification of multiple subunits of the transcription cofactor Mediator complex and transcriptional factors Scalloped (Sd, the TEAD homolog in flies) and E2F1-Dp as novel regulators of TR transcription and telomere length in Drosophila . Depletion of multiple Mediator subunits, Dp, or Sd increased TR expression and telomere length, while over-expressing E2F1-Dp or knocking down the E2F1 regulator Rbf1 (Retinoblastoma-family protein 1) stimulated TR transcription, with Mediator and Sd affecting TR expression through E2F1-Dp. The CUT&RUN analysis revealed direct binding of CDK8, Dp, and Sd to telomeric repeats. These findings highlight the essential role of the Mediator complex in maintaining telomere homeostasis by regulating TR transcription through E2F1-Dp and Sd, revealing the intricate coupling of TR transcription with the host cell-cycle machinery, thereby ensuring chromosome end protection and genomic stability during cell division.

10.
Endocr Relat Cancer ; 29(4): 175-189, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35073278

RESUMO

Thyroid cancer is one of the most common endocrine malignancies. It is necessary to discover more effective molecular targets for the treatment of thyroid cancer. The results of immunohistochemical staining, qPCR and Western blot indicated that the expression of SYT7 in thyroid cancer tissues and cells was higher than that in paracarcinoma tissues and normal thyroid cells. Through cell function testing experiments, it was found that SYT7 knockdown inhibited the proliferation and migration of thyroid cancer cells and promoted cell apoptosis, while SYT7 overexpression had the opposite effect. Similarly, SYT7 downregulation also suppressed tumor growth in vivo. HMGB3 was confirmed to be the downstream gene of SYT7 by GeneChip and Ingenuity Pathway Analysis. Besides, through UbiBrowser database predictions and Co-IP assays, we found that SYT7 interacted with BRCA1 to inhibit HMGB3 ubiquitination and thus upregulated the protein level of HMGB3. Similar to SYT7, HMGB3 was significantly upregulated in thyroid cancer. HMGB3 knockdown inhibited the proliferation and migration of thyroid cancer cells and promoted cell apoptosis. Furthermore, HMGB3 knockdown restored the promotion of cell proliferation and migration caused by SYT7 overexpression. SYT7 and HMGB3 were upregulated in thyroid cancer, and SYT7 regulated the expression of HMGB3 through BRCA1-mediated ubiquitination of HMGB3 to promote thyroid cancer progression.


Assuntos
Proteína HMGB3 , MicroRNAs , Neoplasias da Glândula Tireoide , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Proteína HMGB3/genética , Proteína HMGB3/metabolismo , Humanos , MicroRNAs/genética , Sinaptotagminas/genética , Sinaptotagminas/metabolismo , Neoplasias da Glândula Tireoide/genética , Ubiquitinação
11.
Cancer Manag Res ; 13: 4473-4482, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113173

RESUMO

PURPOSE: The relationship between large thyroid nodules and the risk of malignancy is controversial. This study aimed to examine the relationship between thyroid nodule size and the risk of malignancy of maximal thyroid nodules ≥2 cm and the risk of accompanied by occult thyroid carcinoma. METHODS: This was a retrospective study of patients who underwent near-total or total thyroidectomy for thyroid nodules from January 2016 to January 2019 at the First Affiliated Hospital,Zhejiang University School of Medicine. Clinical, biochemical, and pathological characteristics were examined for association with malignancy using univariable, multivariable, and receiver operating characteristic curve analyses. RESULTS: Finally, 367 patients (277 females (75.5%) and 90 males (24.5%)) with a mean age of 49.0±13.5 years were included. Multivariable logistic regression analysis showed that age (OR=0.959, 95% CI: 0.939-0.979, P<0.001), Hashimoto's thyroiditis (OR=2.437, 95% CI: 1.162-5.112, P=0.018), the diameter of maximal nodule (small) (OR=0.706, 95% CI: 0.541-0.919, P=0.010), and punctate echogenic foci (OR=2.837, 95% CI: 1.598-5.286, P<0.001) were independently associated with malignancy. Of 223 patients who had non-suspicious malignant nodules (TI-RADS <4), 12.7% (n=29) patients showed malignancy at postoperative pathology. Only age was associated with occult PTC in the univariable analyses (OR=0.962, 95% CI: 0.934-0.991, P=0.011). When TPOAb was used as a continuous variable for statistical analysis, it showed a significant difference in the ROC curve, and the results showed TPOAb >31.4 mIU/L was more associated with occult PTC (P=0.006). A predictive model including four independent risk factors of malignancy showed an optimal discriminatory accuracy (area under the curve, AUC) of 0.783 (95% CI=0.732-0.833). CONCLUSION: Relatively young age (<54.5 years), Hashimoto's thyroiditis, the diameter of the maximal nodule, and punctate echogenic foci were independently associated with thyroid malignancy in patients with maximal thyroid nodules ≥2 cm. Young age (<54.5 years) and TPOAb >31.4 mIU/L were associated with occult PTC.

12.
Int J Mol Sci ; 21(20)2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053834

RESUMO

Cyclin-dependent kinase 8 (CDK8) and its regulatory partner Cyclin C (CycC) play conserved roles in modulating RNA polymerase II (Pol II)-dependent gene expression. To understand the structure and function relations of CDK8, we analyzed the structures of human and Drosophila CDK8 proteins using molecular dynamics simulations, combined with functional analyses in Drosophila. Specifically, we evaluated the structural differences between hCDK8 and dCDK8 to predict the effects of the LXXLL motif mutation (AQKAA), the P154L mutations, and drug binding on local structures of the CDK8 proteins. First, we have observed that both the LXXLL motif and the kinase activity of CDK8 are required for the normal larval-to-pupal transition in Drosophila. Second, our molecular dynamic analyses have revealed that hCDK8 has higher hydrogen bond occupation of His149-Asp151 and Asp151-Asn156 than dCDK8. Third, the substructure of Asp282, Phe283, Arg285, Thr287 and Cys291 can distinguish human and Drosophila CDK8 structures. In addition, there are two hydrogen bonds in the LXXLL motif: a lower occupation between L312 and L315, and a relatively higher occupation between L312 and L316. Human CDK8 has higher hydrogen bond occupation between L312 and L316 than dCDK8. Moreover, L312, L315 and L316 in the LXXLL motif of CDK8 have the specific pattern of hydrogen bonds and geometries, which could be crucial for the binding to nuclear receptors. Furthermore, the P154L mutation dramatically decreases the hydrogen bond between L312 and L315 in hCDK8, but not in dCDK8. The mutations of P154L and AQKAA modestly alter the local structures around residues 154. Finally, we identified the inhibitor-induced conformational changes of hCDK8, and our results suggest a structural difference in the drug-binding site between hCDK8 and dCDK8. Taken together, these results provide the structural insights into the roles of the LXXLL motif and the kinase activity of CDK8 in vivo.


Assuntos
Motivos de Aminoácidos , Sítios de Ligação , Quinase 8 Dependente de Ciclina/química , Proteínas de Drosophila/química , Modelos Moleculares , Domínios e Motivos de Interação entre Proteínas , Inibidores de Proteínas Quinases/química , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Quinase 8 Dependente de Ciclina/antagonistas & inibidores , Proteínas de Drosophila/antagonistas & inibidores , Humanos , Ligação de Hidrogênio , Ligantes , Conformação Molecular , Mutação , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Especificidade da Espécie , Relação Estrutura-Atividade
13.
Am J Cancer Res ; 9(8): 1786-1795, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31497359

RESUMO

Currently, no definitive diagnostic tool is available to distinguish unifocal and multifocal papillary thyroid carcinoma (PTC). This study aims to identify potential diagnostic markers of multifocal PTC. In 471 Hashimoto's thyroiditis (HT) patients, the significant difference was revealed in anti-thyroid peroxidase antibody (TPOAb) concentration, the cytokeratin-19 (CK-19) expression, the occurrence of the B-Raf proto-oncogene serine/threonine kinase (BRAF) mutations and the rearrangement in transformation (RET)/PTC. The patients' samples were assayed for the expression of CK-19, cyclooxygenase-2 (COX-2), galectin-3, and the protein human bone marrow endothelial cell marker-1 (HBME-1) using immunohistochemistry. The BRAF gene mutation was detected using a sequencer. Differences were examined using the Kruskal-Wallis test and the Chi-squared and Fisher's exact tests. The results showed that the elevated CK-19 expression, and the presence of BRAF mutations and RET/PTC rearrangements were indicators of multifocal PTC in HT, suggesting the need for total bilateral thyroidectomy. Among HT patients with TPOAb > 1300 IU/Ml, the occurrence of central lymph node metastasis is significantly higher in multi-focal PTC than single-focal PTC. Therefore, these markers may prove useful for discerning between uni- and multifocal PTC, thereby preventing unnecessary surgery in the treatment of unifocal PTC and promoting sufficient treatment of multifocal PTC.

14.
Dev Biol ; 444(2): 62-70, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30352217

RESUMO

The complex interplay between genetic and environmental factors, such as diet and lifestyle, defines the initiation and progression of multifactorial diseases, including cancer, cardiovascular and metabolic diseases, and neurological disorders. Given that most of the studies have been performed in controlled experimental settings to ensure the consistency and reproducibility, the impacts of environmental factors, such as dietary perturbation, on the development of animals with different genotypes and the pathogenesis of these diseases remain poorly understood. By analyzing the cdk8 and cyclin C (cycC) mutant larvae in Drosophila, we have previously reported that the CDK8-CycC complex coordinately regulates lipogenesis by repressing dSREBP (sterol regulatory element-binding protein)-activated transcription and developmental timing by activating EcR (ecdysone receptor)-dependent gene expression. Here we report that dietary nutrients, particularly proteins and carbohydrates, modulate the developmental timing through the CDK8/CycC/EcR pathway. We observed that cdk8 and cycC mutants are sensitive to the levels of dietary proteins and seven amino acids (arginine, glutamine, isoleucine, leucine, methionine, threonine, and valine). Those mutants are also sensitive to dietary carbohydrates, and they are more sensitive to monosaccharides than disaccharides. These results suggest that CDK8-CycC mediates the dietary effects on lipid metabolism and developmental timing in Drosophila larvae.


Assuntos
Quinase 8 Dependente de Ciclina/fisiologia , Proteínas de Drosophila/fisiologia , Larva/metabolismo , Necessidades Nutricionais/fisiologia , Animais , Ciclina C/metabolismo , Ciclina C/fisiologia , Quinase 8 Dependente de Ciclina/metabolismo , Dieta , Proteínas Alimentares/metabolismo , Drosophila/embriologia , Drosophila/genética , Proteínas de Drosophila/metabolismo , Expressão Gênica , Reprodutibilidade dos Testes
15.
Proc Natl Acad Sci U S A ; 114(36): E7469-E7478, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28827348

RESUMO

Deregulated Wnt signaling and altered lipid metabolism have been linked to obesity, diabetes, and various cancers, highlighting the importance of identifying inhibitors that can modulate Wnt signaling and aberrant lipid metabolism. We have established a Drosophila model with hyperactivated Wnt signaling caused by partial loss of axin, a key component of the Wnt cascade. The Axin mutant larvae are transparent and have severe adipocyte defects caused by up-regulation of ß-catenin transcriptional activities. We demonstrate pharmacologic mitigation of these phenotypes in Axin mutants by identifying bortezomib and additional peptide boronic acids. We show that the suppressive effect of peptide boronic acids on hyperactive Wnt signaling is dependent on α-catenin; the rescue effect is completely abolished with the depletion of α-catenin in adipocytes. These results indicate that rather than targeting the canonical Wnt signaling pathway directly, pharmacologic modulation of ß-catenin activity through α-catenin is a potentially attractive approach to attenuating Wnt signaling in vivo.


Assuntos
Adipócitos/efeitos dos fármacos , Ácidos Borônicos/farmacologia , Peptídeos/farmacologia , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Proteína Axina/metabolismo , Drosophila/efeitos dos fármacos , Drosophila/metabolismo , Transcrição Gênica/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , beta Catenina/metabolismo
17.
J Cell Biochem ; 118(11): 3675-3685, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28370286

RESUMO

Colorectal cancer is a common malignant tumor with high incidence affecting the digestive system. This study aimed to identify the key genes relating to prognosis of colorectal cancer and to construct a prognostic model for its risk evaluation. Gene expression profiling of colorectal cancer patients, GSE17537, was downloaded from Gene Expression Omnibus database (GEO). A total of 55 samples from patients ranging from stages 1 to 4 were available. Differentially expressed genes were screened, with which single factor survival analysis was performed to identify the response genes. Interacting network and KEGG enrichment analysis of responsive genes were performed to identify key genes. In return, Fisher enrichment analysis, literature mining, and Kaplan-Meier analysis were used to verify the effectiveness of the prognostic model. The 20-gene model generated in this study posed significant influences on the prognoses (P = 9.691065e-09). Significance was verified via independent dataset GSE38832 (P = 9.86581e-07) and GSE17536 (P = 2.741e-08). The verified effective 20-gene model could be utilized to predict prognosis of patients with colorectal cancer and would contribute to post-operational treatment and follow-up strategies. J. Cell. Biochem. 118: 3675-3685, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Bases de Dados Genéticas , Regulação Neoplásica da Expressão Gênica , Modelos Genéticos , Neoplasias Colorretais/metabolismo , Humanos
18.
PLoS Biol ; 13(7): e1002207, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26222308

RESUMO

The steroid hormone ecdysone and its receptor (EcR) play critical roles in orchestrating developmental transitions in arthropods. However, the mechanism by which EcR integrates nutritional and developmental cues to correctly activate transcription remains poorly understood. Here, we show that EcR-dependent transcription, and thus, developmental timing in Drosophila, is regulated by CDK8 and its regulatory partner Cyclin C (CycC), and the level of CDK8 is affected by nutrient availability. We observed that cdk8 and cycC mutants resemble EcR mutants and EcR-target genes are systematically down-regulated in both mutants. Indeed, the ability of the EcR-Ultraspiracle (USP) heterodimer to bind to polytene chromosomes and the promoters of EcR target genes is also diminished. Mass spectrometry analysis of proteins that co-immunoprecipitate with EcR and USP identified multiple Mediator subunits, including CDK8 and CycC. Consistently, CDK8-CycC interacts with EcR-USP in vivo; in particular, CDK8 and Med14 can directly interact with the AF1 domain of EcR. These results suggest that CDK8-CycC may serve as transcriptional cofactors for EcR-dependent transcription. During the larval-pupal transition, the levels of CDK8 protein positively correlate with EcR and USP levels, but inversely correlate with the activity of sterol regulatory element binding protein (SREBP), the master regulator of intracellular lipid homeostasis. Likewise, starvation of early third instar larvae precociously increases the levels of CDK8, EcR and USP, yet down-regulates SREBP activity. Conversely, refeeding the starved larvae strongly reduces CDK8 levels but increases SREBP activity. Importantly, these changes correlate with the timing for the larval-pupal transition. Taken together, these results suggest that CDK8-CycC links nutrient intake to developmental transitions (EcR activity) and fat metabolism (SREBP activity) during the larval-pupal transition.


Assuntos
Ciclina C/metabolismo , Quinase 8 Dependente de Ciclina/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/crescimento & desenvolvimento , Drosophila/metabolismo , Receptores de Esteroides/metabolismo , Animais , Animais Geneticamente Modificados , Ciclina C/genética , Quinase 8 Dependente de Ciclina/genética , Proteínas de Ligação a DNA/metabolismo , Drosophila/genética , Proteínas de Drosophila/genética , Ecdisteroides/biossíntese , Feminino , Privação de Alimentos , Regulação da Expressão Gênica , Larva/crescimento & desenvolvimento , Larva/metabolismo , Mutação , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo , Fatores de Transcrição/metabolismo
19.
Ying Yong Sheng Tai Xue Bao ; 25(6): 1759-64, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25223035

RESUMO

The effect of swine manure application on nitrate nitrogen leaching was investigated in the Yellow River irrigation area of Ningxia. The field experiment was conducted with 3 Treatments: Traditional fertilization 225 kg N kg x hm(-2) without swine manure (CK), traditional fertilization with swine manure 4500 kg x hm(-2) (T1) and traditional fertilization with swine manure 9000 kg x hm(-2) (T2). Nitrate nitrogen leaching rates were measured for 30, 60, 90 cm depth soil layers with a resin core absorption method. The results indicated that the nitrate leaching losses of T1 and T2 treatments ranged from 9.33 to 14.04 kg x hm(-2) (pure nitrogen), which accounted for 4.2%-6.2% of applied nitrogen fertilizer. Compared to CK, the nitrate leaching losses of T1 and T2 increased by 2.6% and 2.1% at 30 cm depth, increased by 1.5% and decreased by 1.3% at 60 cm depth, decreased by 8.7% and increased by 4.0% at 90 cm depth, respectively. The difference did not reach statistical significance among CK and T1 and T2 in nitrate leaching loss at 30, 60 and 90 cm depths. However, there was a declining trend of nitrate leaching at deep soil layers of treatments. The key period of nitrate leaching loss was from spring reviving to early filling stage, which had a higher daily leaching loss than the average of the whole growth period, and accounted for 58.7%-75.3% of total leaching loss. Compared with CK, the yields of T1 and T2 increased by 9.3% and 12.5%, respectively.


Assuntos
Fertilizantes , Esterco , Nitratos/análise , Triticum , Poluentes Químicos da Água/análise , Irrigação Agrícola , Animais , China , Nitrogênio/análise , Rios , Solo/química , Suínos
20.
Mech Dev ; 133: 36-53, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25016215

RESUMO

Post-translational modification of histones plays essential roles in the transcriptional regulation of genes in eukaryotes. Methylation on basic residues of histones is regulated by histone methyltransferases and histone demethylases, and misregulation of these enzymes has been linked to a range of diseases such as cancer. Histone lysine demethylase 2 (KDM2) family proteins have been shown to either promote or suppress tumorigenesis in different human malignancies. However, the roles and regulation of KDM2 in development are poorly understood, and the exact roles of KDM2 in regulating demethylation remain controversial. Since KDM2 proteins are highly conserved in multicellular animals, we analyzed the KDM2 ortholog in Drosophila. We have observed that dKDM2 is a nuclear protein and its level fluctuates during fly development. We generated three deficiency lines that disrupt the dKdm2 locus, and together with 10 transposon insertion lines within the dKdm2 locus, we characterized the developmental defects of these alleles. The alleles of dKdm2 define three phenotypic classes, and the intragenic complementation observed among these alleles and our subsequent analyses suggest that dKDM2 is not required for viability. In addition, loss of dKDM2 appears to have rather weak effects on histone H3 lysine 36 and 4 methylation (H3K36me and H3K4me) in the third instar wandering larvae, and we observed no effect on methylation of H3K9me2, H3K27me2 and H3K27me3 in dKdm2 mutants. Taken together, these genetic, molecular and biochemical analyses suggest that dKDM2 is not required for viability of flies, indicating that dKdm2 is likely redundant with other histone lysine demethylases in regulating normal development in Drosophila.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/enzimologia , Drosophila melanogaster/genética , Histona Desmetilases com o Domínio Jumonji/genética , Animais , Animais Geneticamente Modificados , Deleção Cromossômica , Sequência Conservada , Elementos de DNA Transponíveis , Proteínas de Drosophila/química , Proteínas de Drosophila/deficiência , Drosophila melanogaster/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Técnicas de Inativação de Genes , Genes de Insetos , Teste de Complementação Genética , Humanos , Histona Desmetilases com o Domínio Jumonji/química , Histona Desmetilases com o Domínio Jumonji/deficiência , Mutação , Filogenia , Estrutura Terciária de Proteína
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