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1.
Appl Opt ; 63(7): 1881-1887, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437294

RESUMO

The probabilistic shaping (PS) technique is a key technology for fiber optic communication systems to further approach the Shannon limit. To solve the problem that nonlinear equalizers are ineffective for probabilistic shaping optical communication systems with non-uniform distribution, a distribution alignment convolutional neural network (DACNN)-aided nonlinear equalizer is proposed. The approach calibrates the equalizer using the probabilistic shaping prior distribution, which reduces the training complexity and improves the performance of the equalizer simultaneously. Experimental results show nonlinear equalization of 120 Gb/s PS 64QAM signals in a 375 km transmission scenario. The proposed DACNN equalizer improves the receiver sensitivity by 2.6 dB and 1.1 dB over the Volterra equalizer and convolutional neural network (CNN) equalizer, respectively. Meanwhile, DACNN converges with fewer training epochs than CNN, which provides great potential for mitigating the nonlinear distortion of PS signals in fiber optic communication systems.

2.
BMC Nephrol ; 25(1): 26, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254024

RESUMO

BACKGROUND: Up to now, there is no unequivocal intervention to mitigate vascular calcification (VC) in patients with hemodialysis. This network meta-analysis aimed to systematically evaluate the clinical efficacy of sodium thiosulfate, bisphosphonates, and cinacalcet in treating vascular calcification. METHODS: A comprehensive study search was performed using PubMed, Web of Science, the Cochrane Library, EMBASE and China National Knowledge Internet (CNKI) to collect randomized controlled trials (RCTs) of sodium thiosulfate, bisphosphonates, and cinacalcet for vascular calcification among hemodialysis patients. Then, network meta-analysis was conducted using Stata 17.0 software. RESULTS: In total, eleven RCTs including 1083 patients were qualified for this meta-analysis. We found that cinacalcet (SMD - 0.59; 95% CI [-0.95, -0.24]) had significant benefit on vascular calcification compared with conventional therapy, while sodium thiosulfate or bisphosphonates did not show such efficiency. Furthermore, as for ranking the efficacy assessment, cinacalcet possessed the highest surface under the cumulative ranking curve (SUCRA) value (88.5%) of lessening vascular calcification and was superior to sodium thiosulfate (50.4%) and bisphosphonates (55.4%). Thus, above results suggested that cinacalcet might be the most promising drug for vascular calcification treatment in hemodialysis patients. Mechanistically, our findings illustrated that cinacalcet reduced serum calcium (SMD - 1.20; 95% CI [-2.08, - 0.33]) and showed the tendency in maintaining the balance of intact Parathyroid Hormone (iPTH) level. CONCLUSIONS: This network meta-analysis indicated that cinacalcet appear to be more effective than sodium thiosulfate and bisphosphonates in mitigating vascular calcification through decreasing serum calcium and iPTH. And cinacalcet might be a reasonable option for hemodialysis patients with VC in clinical practice. SYSTEMATIC REVIEW REGISTRATION: [ http://www.crd.york.ac.uk/PROSPERO ], identifier [CRD42022379965].


Assuntos
Difosfonatos , Tiossulfatos , Calcificação Vascular , Humanos , Difosfonatos/uso terapêutico , Cinacalcete/uso terapêutico , Metanálise em Rede , Cálcio , Calcificação Vascular/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Nano Lett ; 23(14): 6323-6329, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37459426

RESUMO

There remains continued interest in improving the advanced water oxidation process [e.g., ultraviolet (UV)/hydrogen peroxide (H2O2)] for more efficient and environmentally friendly wastewater treatment. Here, we report the design, fabrication, and performance of graphene oxide (GO, on top)/nickel-doped iron oxyhydroxide (Ni:FeOOH, shell)/silicon nanowires (SiNWs, core) as a new multifunctional photocatalyst for the degradation of common pollutants like polystyrene and methylene blue through enhancing the hydroxyl radical (•OH) production rate of the UV/H2O2 system. The photocatalyst combines the advantages of a large surface area and light absorption characteristics of SiNWs with heterogeneous photo-Fenton active Ni:FeOOH and photocatalytically active/charge separator GO. In addition, the built-in electric field of GO/Ni:FeOOH/SiNWs facilitates the charge separation of electrons to GO and holes to Ni:FeOOH, thus boosting the photocatalytic performance. Our photocatalyst increases the •OH yield by 5.7 times compared with that of a blank H2O2 solution sample and also extends the light absorption spectrum to include visible light irradiation.

4.
Appl Opt ; 62(32): 8543-8551, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38037967

RESUMO

In this work, a low-complexity data-driven characterized-long-short-term-memory (C-LSTM)-aided channel modeling technique is proposed for optical single-mode fiber (SMF) communications. To fully utilize the sequence correlation learning ability of traditional long short-term memory (LSTM) networks and solve the gradient explosion problem, the feature information is introduced into the traditional LSTM input layer to better characterize the intersymbol interference caused by dispersion in SMF modeling. The simulation results show that the proposed C-LSTM can effectively alleviate the gradient explosion problem with a stable and ultimately lower mean square error (MSE) than traditional LSTM. Compared with the split-step Fourier method (SSFM) and the conditional generative adversarial network (CGAN), the proposed C-LSTM has superior computational complexity. Moreover, due to the sequence correlation learning ability inherent to C-LSTM, coupled with the flexibility of feature information selection, the proposed C-LSTM-aided modeling technique has a higher modeling accuracy than traditional LSTM. Moreover, the C-LSTM-aided modeling technique can be effectively extended to other channel modeling applications with strong sequence correlations.

5.
J Clin Nurs ; 32(17-18): 5886-5903, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37016501

RESUMO

BACKGROUND: Diabetes has become a global public health problem. Strengthening the self-management ability of people with prediabetes plays an important role in preventing the occurrence and development of type 2 diabetes. The aim of this study is to synthesise the self-management experiences and perceptions of people with prediabetes, which can contribute to the development of self-management programs. METHODS: This review adheres to the ENTREQ Guide. Evidence-based medicine database (JBI and Cochrane) and original literature database (PubMed, Medline, EMbase, Web of Science, Wanfang, CNKI and VIP) were searched up to 31 May 2022. Both Chinese and English literature of qualitative research on self-management experiences and perceptions of prediabetic patients were included. The quality of the included studies was evaluated, and the data were synthesised and analysed by thematic synthesis method. RESULTS: A total of 23 primary studies containing 504 participants were included. After repeated reading and coding of the literature, three analytical themes were finally identified: coping with role management, success and failure in medical management, seeking and perceiving support. CONCLUSION: Role management for people with prediabetes needs more attention. Healthcare providers should identify problems from patients' self-management experiences and improve professional skills to assist program modifications. Integrating the self-management program into community activities under the guidance of medical staff and inviting family members and peers to participate can increase involvement and improve the self-management ability. RELEVANCE TO CLINICAL PRACTICE: These findings describe the different stages and issues in the self-management process of prediabetic patients. The practice of prediabetes self-management should incorporate the psychosocial, physical, and financial issues of the patients. As the main provider of health services, nurses should make patients aware of the susceptibility and severity of prediabetes and help them improve their self-management skills. NO PATIENT OR PUBLIC CONTRIBUTION: This is a meta-synthesis without direct participation of patients.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Autogestão , Humanos , Diabetes Mellitus Tipo 2/terapia , Pessoal de Saúde , Serviços de Saúde , Estado Pré-Diabético/terapia , Pesquisa Qualitativa
6.
Int J Colorectal Dis ; 37(6): 1449-1464, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35482069

RESUMO

PURPOSE: DNA mismatch repair (MMR) protein deficiency has attached more attention for its potential to be a biomarker of immunotherapy for colorectal cancer (CRC) patients. However, clinical models involving the expression status of MMR protein are rare. Herein, we sought to develop two clinical models (a diagnostic model for the prediction of MMR status and a prognostic model for the prediction of disease-free survival) for CRC patients. METHODS: A total of 582 CRC patients were finally included. There were 53 patients with deficient expression of MMR protein. The differences between the deficient MMR (dMMR) group and the proficient MMR (pMMR) group were analyzed. RESULTS: Compared to pMMR patients, those with dMMR status were younger and had better pathological features (depth of invasion, lymph node metastasis, distant metastasis, pathological stage, perineuronal invasion, and PLT level) and disease-free survival (DFS). The tumor location of the left colon, adenocarcinoma, and abnormal PLT level were identified as the independent predictors for pMMR. Based on these data, we developed the diagnostic model using Logistic regression analysis. It showed a satisfactory accuracy (AUC = 82.3% in the derivate set; AUC = 73.6% in the validation set). Furthermore, pMMR, poorer differentiation, perineuronal invasion, distant metastasis, lower hemoglobin level, and abnormal CEA level were established as the independent prognostic factors of poorer DFS. Based on them, a prognostic model with valuable performance (1-year AUC = 75.5%/3-year AUC = 76.9% in the derivate set; 1-year AUC = 72.3%/3-year AUC = 73.8% in the validation set) was developed. CONCLUSIONS: Our diagnostic and prognostic models could identify CRC patients at risk for pMMR protein expression and disease recurrence. It may contribute to improving the diagnosis and treatment of CRC patients at an individual level.


Assuntos
Neoplasias Colorretais , Deficiência de Proteína , Neoplasias Encefálicas , Neoplasias Colorretais/patologia , Reparo de Erro de Pareamento de DNA/genética , Intervalo Livre de Doença , Humanos , Recidiva Local de Neoplasia , Síndromes Neoplásicas Hereditárias , Prognóstico
7.
BMC Cancer ; 21(1): 974, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34461860

RESUMO

BACKGROUND: This study compared the long-term efficacy of different durations of adjuvant chemotherapy for patients with gastric cancer after radical gastrectomy with D2 lymphadenectomy. METHODS: We retrospectively identified 428 patients with stage II-III gastric cancer who underwent D2 gastrectomy between 2009 and 2016. Patients were divided into four groups according to the duration of adjuvant chemotherapy, including 0 week (no adjuvant, group A), 20 to 24 weeks (completed 7-8 cycles every 3 weeks or 10-12 cycles every 2 weeks, group B), and 12 to18 weeks (completed 4-6 cycles every 3 weeks or 6-9 cycles every 2 weeks, group C), and less than 12 weeks (received up to 3 cycles every 3 weeks or 5 cycles every 2 weeks, group D). The chemotherapy regimens included XELOX, SOX, and FOLFOX. 5-year overall survival (OS) and disease-free survival (DFS) were analyzed. RESULTS: The 5-year OS rates for groups A, B, C, and D were 52.3, 73.7, 72.0, and 53.3%, respectively, and the 5-year DFS rates were 50.0, 68.0, 65.4, and 50.0%, respectively. OS and DFS were higher in group B than in groups A and D. Similarly, patients in group C were more likely to have higher OS and DFS than those in groups A and D. Meanwhile, there were no significant differences in OS and DFS between groups B and C. The multivariate analysis confirmed with high statistical significance the efficacy of complete courses of adjuvant chemotherapy, and, among them, the similar impact of 4-6/6-9 and 7-8/10-12 cycles, resulting in similar HRs vs Group A (0.52 and 0.42, respectively). CONCLUSIONS: To reduce toxicity and maintain efficacy, XELOX or SOX chemotherapy regimens administered for 4-6 cycles every 3 weeks or FOLFOX regimen for 6-9 cycles every 2 weeks might be a favorable option for patients with stage II-III gastric cancer after D2 gastrectomy. Prospective multicenter clinical trials with adequate sample sizes are necessary to verify these findings.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante/mortalidade , Gastrectomia/mortalidade , Excisão de Linfonodo/mortalidade , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida , Adulto Jovem
8.
Regul Toxicol Pharmacol ; 123: 104943, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33933548

RESUMO

In the present study, a new genetically modified rice producing phytase-lactoferricin fusion protein, BPL9K-4, was evaluated for safety in a 90-day rat feeding study. Rats were fed rodent diets formulated with BPL9K-4 rice, and were compared with rats fed diets formulated with its corresponding non-transgenic parental rice 9 K, commercially available non-transgenic rice Weiyou64, and a basal diet. BPL9K-4 and 9 K rice were formulated into diets at concentrations of 15%, 30% and 60%, and Weiyou64 common rice was added to diets at concentration of 60%. AIN93G diet was set as a basal-diet control. Diets of all groups were fed to rats (10/sex/group) for 90 days. Compared with rats in the 9 K, Weiyou64 and the basal-diet group, rats fed the BPL9K-4 diet did not show any treatment-related adverse effects on mortality, body weights, feed consumption, clinical chemistry, hematology, organ weights and gross and microscopic pathology. Under the conditions of this study, the genetically modified BPL9K-4 diets did not cause any toxicologically significant effects in rats following 90 days of dietary administration as compared with rats fed diets with the corresponding non-transgenic control diet and the basal-diet group. The results indicated that BPL9K-4 rice is as safe as its conventional comparators.


Assuntos
Alimentos Geneticamente Modificados , Oryza , Testes de Toxicidade Subcrônica , Ração Animal , Animais , Dieta , Tamanho do Órgão , Plantas Geneticamente Modificadas , Ratos , Roedores , Zea mays
9.
J Clin Lab Anal ; 35(11): e24029, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34590736

RESUMO

BACKGROUND: Accurately measuring plasma aldosterone concentration is difficult but meaningful for primary aldosteronism (PA) diagnosis. METHODS: In this study, we developed an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for plasma aldosterone detection, evaluated its performance according to guidelines issued by CLSI, including detection limit, linearity, precision, and compared it with chemiluminescence immunoassay. Then, a reference range of plasma aldosterone in young people was established by using this method. RESULTS: The lower limit of quantitation (LOQ) was 10 pg/ml. The mean recovery rates of analyte added to serum were 100.07-102.05% in different concentrations. The linearity range was 20-2000 pg/ml. Inter-assay CVs were 2.20-3.97% at aldosterone concentrations of 65.66-854.75 pg/ml. The regression equation of UPLC-MS/MS (x) and chemiluminescence immunoassay (y) was y = 1.002x + 65.854 (r = 0.9456, n = 237). The reference range of plasma aldosterone detected by UPLC-MS/MS was 11.30-363.82 pg/ml in young people in South China, and there was no statistically significant difference in plasma aldosterone concentration between two genders. CONCLUSION: In conclusion, UPLC-MS/MS can rapidly and accurately detect plasma aldosterone and is appropriate for clinical application.


Assuntos
Aldosterona/sangue , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Adulto , Feminino , Humanos , Hiperaldosteronismo , Limite de Detecção , Modelos Lineares , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
10.
J Cell Physiol ; 235(6): 5111-5119, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31667864

RESUMO

Lupus nephritis (LN) is the most common complication of systemic lupus erythematosus. Patients with LN mostly die of sclerosing glomerulonephritis and renal failure. The inhibition of glomerular mesangial matrix deposition is an efficient method to restrict the progress of renal injury. By recognizing and binding extracellular and intracellular ligands, Toll-like receptor 2 (TLR2) contributes to the pathogenesis of most immune diseases. However, the relationship between TLR2 and LN is still unknown. Our previous studies confirmed that high-mobility group box 1 (HMGB1), an important ligand of TLR2, promotes the progression of LN by inducing the proliferation of glomerular mesangial cells. However, whether or not HMGB1 participates in the pathogenesis of glomerular mesangial matrix deposition in LN remains unknown. In this study, we observed the upregulated expression of TLR2 in the glomeruli of LN patients and MRL/lpr mice. The inhibition of either TLR2 or HMGB1 inhibited the release of fibronectin and the activation of the MyD88/NF-κB pathway in mesangial cells cultured with LN plasma. In addition, both TLR2- and HMGB1-deficient mice showed reduced 24 hr urine protein levels and improved glomerular histological changes and sclerosis levels. These results indicate that TLR2 regulates glomerular mesangial matrix deposition in LN through the activation of the MyD88/NF-κB pathway by binding to HMGB1.


Assuntos
Mesângio Glomerular/metabolismo , Proteína HMGB1/genética , Nefrite Lúpica/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Receptor 2 Toll-Like/genética , Adulto , Animais , Proliferação de Células/genética , Feminino , Mesângio Glomerular/patologia , Humanos , Ligantes , Nefrite Lúpica/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , NF-kappa B/genética , Ligação Proteica/genética , Adulto Jovem
11.
J Cell Physiol ; 234(7): 11555-11566, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30648253

RESUMO

TRIM27 (tripartite motif-containing 27) is a member of the TRIM (tripartite motif) protein family and participates in a variety of biological processes. Some research has reported that TRIM27 was highly expressed in certain kinds of carcinoma cells and tissues and played an important role in the proliferation of carcinoma cells. However, whether TRIM27 takes part in the progression of lupus nephritis (LN) especially in cells proliferation remains unclear. Our study revealed that the overexpression of TRIM27 was observed in the kidneys of patients with LN, lupus mice and mesangial cells exposed to LN plasma which correlated with the proliferation of mesangial cells and ECM (extracellular matrix) deposition. Downregulation of TRIM27 expression suppressed the proliferation of mesangial cells and ECM accumulation in MRL/lpr mice and cultured human mesangial cells (HMCs) by regulating the FoxO1 pathway. Furthermore, the overexpression of FoxO1 remarkably decreased HMCs proliferation level and ECM accumulation in LN plasma-treated HMCs. In addition, the protein kinase B (Akt) signal pathway inhibitor LY294002 significantly reduced the expression of TRIM27 and inhibited the dysfunction of mesangial cells. These above data suggested that TRIM27 mediated abnormal mesangial cell proliferation in kidney of lupus and might be the potential target for treating mesangial cell proliferation of lupus nephritis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteína Forkhead Box O1/metabolismo , Nefrite Lúpica/metabolismo , Células Mesangiais/metabolismo , Células Mesangiais/patologia , Proteínas Nucleares/metabolismo , Adulto , Animais , Células Cultivadas , Proteínas de Ligação a DNA/genética , Regulação para Baixo , Feminino , Proteína Forkhead Box O1/genética , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Camundongos , Camundongos Endogâmicos MRL lpr , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
12.
Appl Microbiol Biotechnol ; 103(12): 4869-4880, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31053912

RESUMO

The yeast Saccharomyces cerevisiae has been widely used as a model system for studying the physiological and pharmacological action of small-molecular drugs. Here, a heterozygous diploid S. cerevisiae strain QSS4 was generated to determine whether drugs could induce chromosomal instability by determining the frequency of mitotic recombination. Using the combination of a custom SNP microarray and yeast screening system, the patterns of chromosomal instability induced by drugs were explored at the whole genome level in QSS4. We found that Zeocin (a member of the bleomycin family) treatment increased the rate of genomic alterations, including aneuploidy, loss of heterozygosity (LOH), and chromosomal rearrangement over a hundred-fold. Most recombination events are likely to be initiated by DNA double-stand breaks directly generated by Zeocin. Another remarkable finding is that G4-motifs and low GC regions were significantly underrepresented within the gene conversion tracts of Zeocin-induced LOH events, indicating that certain DNA regions are less preferred Zeocin-binding sites in vivo. This study provides a novel paradigm for evaluating genetic toxicity of small-molecular drugs using yeast models.


Assuntos
Instabilidade Cromossômica/efeitos dos fármacos , Cromossomos Fúngicos , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Bibliotecas de Moléculas Pequenas/farmacologia , Aneuploidia , Bleomicina/farmacologia , Divisão Celular , Rearranjo Gênico , Instabilidade Genômica , Perda de Heterozigosidade , Recombinação Genética
13.
Arch Toxicol ; 92(6): 1913-1923, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29721585

RESUMO

As a vital member of AAA+ (ATPase associated with diverse cellular activities) protein superfamily, Lon, a homo-hexameric ring-shaped protein complex with a serine-lysine catalytic dyad, is highly conserved throughout almost all prokaryotic and eukaryotic organisms. Lon protease (LONP) plays an important role in maintaining mitoproteostasis through selectively recognizing and degrading oxidatively modified mitoproteins within mitochondrial matrix, such as oxidized aconitase, phosphorylated mitochondrial transcription factor A, etc. Furthermore, the up-regulated LONP increased mitochondrial ROS generation to promote cell survival, cell proliferation, epithelial-mesenchymal transition, and cell migration, which was attributed to the up-regulation of NADH:ubiquinone oxidoreductase core subunit S8 via interaction with chaperone Lon under hypoxic or oxidative stress in tumorigenesis. In addition, Lon also participated in protein kinase RNA (PKR)-like endoplasmic reticulum kinase signaling pathway under endoplasmic reticulum (ER) stress. In short, Lon, as a pivotal stress-responsive protein that involved in the crosstalks among mitochondria, ER and nucleus, participated in multifarious important cellular processes crucial for cell survival, such as the mitochondrial protein quality control system, the mitochondrial unfolded protein response, the mtDNA maintenance, and the ER unfolded protein response.


Assuntos
Retículo Endoplasmático/metabolismo , Homeostase/fisiologia , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Protease La/metabolismo , Animais , Proteínas de Ligação a DNA/metabolismo , Retículo Endoplasmático/enzimologia , Estresse do Retículo Endoplasmático/fisiologia , Humanos , Mitocôndrias/enzimologia , Chaperonas Moleculares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/metabolismo
14.
Regul Toxicol Pharmacol ; 95: 220-226, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29530616

RESUMO

Mulberry (Morus alba L.) leaves are of broad popular use for food or remedy purposes due to their bioactive properties, especially antidiabetic activity and antioxidative activity. The present study aimed to assess the toxicological profile of mulberry leaf extract (MLE), through acute, subacute toxicity and genotoxicity tests. Male and female rats received by gavage 15.0 g/kg bw of MLE in the acute toxicity test, and 0, 1.88, 3.75 and 7.50 g/kg bw/d of MLE for subacute toxicity test. In the acute toxicity study, no mortality or behavioral changes were observed, indicating the LD50 is higher than 15.0 g/kg bw. In the subacute toxicity test, no significant changes were observed in hematological, biochemical or histopathological parameters in the animals exposed. The no-observed-adverse-effect level in the subacute toxicity study was considered to be 7.50 g/kg bw/d, the highest dose tested. In the genotoxicity study, MLE showed no mutagenic activity in the Ames assay and no evidence of potential to induce chromosome aberrations or sperm abnormalities in mice exposed to 10 g/kg bw. Collectively, aqueous extract of mulberry leaves could be considered safe, and the results support the application of MLE as novel food ingredient or product.


Assuntos
Morus , Extratos Vegetais/toxicidade , Animais , Feminino , Dose Letal Mediana , Masculino , Camundongos , Testes de Mutagenicidade , Nível de Efeito Adverso não Observado , Folhas de Planta , Ratos Sprague-Dawley , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Espermatozoides/efeitos dos fármacos , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
15.
PLoS Comput Biol ; 12(9): e1005099, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27617747

RESUMO

Uncertainty of fear conditioning is crucial for the acquisition and extinction of fear memory. Fear memory acquired through partial pairings of a conditioned stimulus (CS) and an unconditioned stimulus (US) is more resistant to extinction than that acquired through full pairings; this effect is known as the partial reinforcement extinction effect (PREE). Although the PREE has been explained by psychological theories, the neural mechanisms underlying the PREE remain largely unclear. Here, we developed a neural circuit model based on three distinct types of neurons (fear, persistent and extinction neurons) in the amygdala and medial prefrontal cortex (mPFC). In the model, the fear, persistent and extinction neurons encode predictions of net severity, of unconditioned stimulus (US) intensity, and of net safety, respectively. Our simulation successfully reproduces the PREE. We revealed that unpredictability of the US during extinction was represented by the combined responses of the three types of neurons, which are critical for the PREE. In addition, we extended the model to include amygdala subregions and the mPFC to address a recent finding that the ventral mPFC (vmPFC) is required for consolidating extinction memory but not for memory retrieval. Furthermore, model simulations led us to propose a novel procedure to enhance extinction learning through re-conditioning with a stronger US; strengthened fear memory up-regulates the extinction neuron, which, in turn, further inhibits the fear neuron during re-extinction. Thus, our models increased the understanding of the functional roles of the amygdala and vmPFC in the processing of uncertainty in fear conditioning and extinction.


Assuntos
Tonsila do Cerebelo/fisiologia , Medo/fisiologia , Memória/fisiologia , Modelos Neurológicos , Córtex Pré-Frontal/fisiologia , Condicionamento Psicológico/fisiologia , Humanos , Vias Neurais/fisiologia , Neurônios/fisiologia , Reforço Psicológico , Incerteza
16.
Int J Biometeorol ; 60(6): 827-41, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26449350

RESUMO

Water-use efficiency (WUE), which links carbon and water cycles, is an important indicator of assessing the interactions between ecosystems and regional climate. Using chamber methods with and without plant removal treatments, we investigated WUE and evapotranspiration (ET) components in three ecosystems with different land-use types in Northern China pastoral-farming ecotone. In comparison, ET of the ecosystems with grazing exclusion and cultivating was 6.7 and 13.4 % higher than that of the ecosystem with free grazing. The difference in ET was primarily due to the different magnitudes of soil water evaporation (E) rather than canopy transpiration (T). Canopy WUE (WUEc, i.e., the ratio of gross primary productivity to T) at the grazing excluded and cultivated sites was 17 and 36 % higher than that at the grazing site. Ecosystem WUE (WUEnep, i.e., the ratio of net ecosystem productivity to ET) at the cultivated site was 34 and 28 % lower in comparison with grazed and grazing excluded stepped, respectively. The varied leaf area index (LAI) of different land uses was correlated with microclimate and ecosystem vapor/carbon exchange. The LAI changing with land uses should be the primary regulation of grassland WUE. These findings facilitate the mechanistic understanding of carbon-water relationships at canopy and ecosystem levels and projection of the effects of land-use change on regional climate and productivity.


Assuntos
Ecossistema , Água , Agricultura , Biomassa , Dióxido de Carbono/metabolismo , China , Modelos Teóricos , Transpiração Vegetal , Solo/química , Volatilização , Água/química , Água/metabolismo , Tempo (Meteorologia)
17.
Parasitol Res ; 113(2): 491-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24276643

RESUMO

Schistosomiasis threatens thousands of millions of peoples' health every year in the world. Schistosoma japonicum, a pathogen of schistosomiasis, is covered by a lipid bilayer membrane which plays an important role in nutrient transport, signal transduction, interaction with host's immune system, etc. Thus, molecules in the tegumental membrane have gained more and more interest for understanding biological and pathological processes of schistosoma. In this study, we found a protein from S. japonicum cDNA library which has a 20.8 KDa molecular weight (SjTP20.8). Recombinant SjTP20.8 was produced and purified from Escherichia coli. The recombinant protein could be detected by S. japonicum-infected mice and human sera, and it had been found localizing in the tegumental membrane of S. japonicum in the section using immunofluorescence assay. In electrophoretic mobility shift assay, the protein could bind calcium iron in neutral condition. Result of cercariae challenge experiment indicates antibody against this protein can protect mice from chronic hepatic fibrosis. Our results indicate the S. japonicum tegumental protein 20.8 is crucial for the parasite's calcium absorbing and reproduction.


Assuntos
Cálcio/metabolismo , Proteínas de Helminto/metabolismo , Reprodução , Schistosoma japonicum/fisiologia , Esquistossomose Japônica/parasitologia , Sequência de Aminoácidos , Animais , Anticorpos Anti-Helmínticos/imunologia , Sequência de Bases , Clonagem Molecular , Escherichia coli/genética , Feminino , Imunofluorescência , Proteínas de Helminto/química , Proteínas de Helminto/imunologia , Proteínas de Helminto/isolamento & purificação , Imunização , Cirrose Hepática/parasitologia , Cirrose Hepática/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Peso Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Schistosoma japonicum/genética , Schistosoma japonicum/imunologia
18.
Cell Syst ; 15(6): 578-592.e7, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38823396

RESUMO

Computational methods are desired for single-cell-resolution spatial transcriptomics (ST) data analysis to uncover spatial organization principles for how individual cells exert tissue-specific functions. Here, we present ST data analysis via interaction-aware cell embedding (SPACE), a deep-learning method for cell-type identification and tissue module discovery from single-cell-resolution ST data by learning a cell representation that captures its gene expression profile and interactions with its spatial neighbors. SPACE identified spatially informed cell subtypes defined by their special spatial distribution patterns and distinct proximal-interacting cell types. SPACE also automatically discovered "cell communities"-tissue modules with discernible boundaries and a uniform spatial distribution of constituent cell types. For each cell community, SPACE outputs a characteristic proximal cell-cell interaction network associated with physiological processes, which can be used to refine ligand-receptor-based intercellular signaling analyses. We envision that SPACE can be used in large-scale ST projects to understand how proximal cell-cell interactions contribute to emergent biological functions within cell communities. A record of this paper's transparent peer review process is included in the supplemental information.


Assuntos
Comunicação Celular , Análise de Célula Única , Transcriptoma , Análise de Célula Única/métodos , Comunicação Celular/genética , Transcriptoma/genética , Humanos , Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Animais , Aprendizado Profundo
19.
Clin Neuroradiol ; 34(2): 485-494, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38416142

RESUMO

PURPOSE: Tortuosity of the internal carotid artery (ICA) is associated with intracranial aneurysms (IAs). The siphon is the most curved segment of the ICA, but its morphology has controversial effects on IAs. This study aimed to explore the morphometric features of the siphon and the potential hemodynamic mechanisms that may affect C7 aneurysm formation. METHODS: In this study 32 patients with C7 aneurysms diagnosed at Xiangya Hospital between 2019 and 2021 and 32 control subjects were enrolled after propensity score matching. Computed tomography angiography (CTA) images were acquired to measure morphologic features, and then, by combining clinical data, simplified carotid siphon models were constructed, and computational fluid dynamics (CFD) analysis was performed. RESULTS: The presence of C7 aneurysms was associated with the height of the C4-C6 curved arteries (odds ratio [OR] 0.028, 95% confidence interval [CI] 0.003-0.201; P < 0.001). The heights of the C4-C6 curved arteries in the aneurysm group were significantly shorter than those in the control group. The CFD analysis revealed that shorter C4-C6 bends led to greater blood velocity and pressure in the C7 segment arteries. CONCLUSION: A shorter C4-C6 bend was associated with distal C7 aneurysm formation, and an elaborate hemodynamic mechanism may underlie this association.


Assuntos
Artéria Carótida Interna , Angiografia por Tomografia Computadorizada , Aneurisma Intracraniano , Humanos , Feminino , Masculino , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Estudos de Casos e Controles , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/fisiopatologia , Pessoa de Meia-Idade , Hidrodinâmica , Angiografia Cerebral , Adulto , Idoso , Pontuação de Propensão , Velocidade do Fluxo Sanguíneo
20.
Foods ; 13(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731698

RESUMO

Quinoa (Chenopodium quinoa Willd.) seeds are rich in nutrition, superior to other grains, and have a high market value. However, the biosynthesis mechanisms of protein, starch, and lipid in quinoa grain are still unclear. The objective of this study was to ascertain the nutritional constituents of white, yellow, red, and black quinoa seeds and to employ a multi-omics approach to analyze the synthesis mechanisms of these nutrients. The findings are intended to furnish a theoretical foundation and technical support for the biological breeding of quinoa in China. In this study, the nutritional analysis of white, yellow, red, and black quinoa seeds from the same area showed that the nutritional contents of the quinoa seeds were significantly different, and the protein content increased with the deepening of color. The protein content of black quinoa was the highest (16.1 g/100 g) and the lipid content was the lowest (2.7 g/100 g), among which, linoleic acid was the main fatty acid. A combined transcriptome and metabolome analysis exhibited that differentially expressed genes were enriched in "linoleic acid metabolism", "unsaturated fatty acid biosynthesis", and "amino acid biosynthesis". We mainly identified seven genes involved in starch synthesis (LOC110716805, LOC110722789, LOC110738785, LOC110720405, LOC110730081, LOC110692055, and LOC110732328); five genes involved in lipid synthesis (LOC110701563, LOC110699636, LOC110709273, LOC110715590, and LOC110728838); and nine genes involved in protein synthesis (LOC110710842, LOC110720003, LOC110687170, LOC110716004, LOC110702086, LOC110724454 LOC110724577, LOC110704171, and LOC110686607). The data presented in this study based on nutrient, transcriptome, and metabolome analyses contribute to an enhanced understanding of the genetic regulation of seed quality traits in quinoa, and provide candidate genes for further genetic improvements to improve the nutritional value of quinoa seeds.

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