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1.
BMC Public Health ; 23(1): 1819, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726699

RESUMO

BACKGROUND: Schools play an organizational role in managing myopia-related behavioral habits among students. We evaluated the effects of school myopia management measures on myopia onset and progression in a school-based prospective 1-year observational study. METHODS: In total, 8319 children from 26 elementary schools were included. Online questionnaire completed by a parent, in which school myopia management experience including outdoor activities in recess or physical education class, teachers' supervision, and teaching facilities. Variables were defined as implemented well or poorly, according to the Comprehensive Plan to Prevent Myopia among Children and Teenagers. Children underwent ophthalmic examinations, and the incidence and progression of myopia from 2019 to 2020 were estimated. Multilevel logistic regression models were constructed to analyze the association between school management measures and myopia development in 8,9 years and 10,11 years students. RESULTS: From 2019 to 2020, the incidence of myopia among primary school students was 36.49%; the mean difference of spherical equivalent in myopic children was - 0.29 ± 1.22 diopters. The risk of incident myopia was reduced by 20% in 8,9 years participants with well-implemented class recess compared with those with poorly implemented class recess (adjusted odds ratio [aOR]: 0.80, p = 0.032). PE outdoor time was significantly associated with myopia incidence in 10,11 years students (aOR: 0.76, p = 0.043). Compared with poorly implemented reading and writing posture, desk and chair height, 10,11 participants with well-implemented desk and chair height were less likely to have rapid myopic progression (p = 0.029, p = 0.022). CONCLUSION: In Shanghai, children's myopia is associated with better implementation of school myopia management measures. The present findings suggest that outdoor activities during class recess or PE class, providing suitable desks and chairs, and adequate instruction in reading and writing postures might protect against pathological eye growth. An age-specific myopia prevention and control programs in school is of primary importance.


Assuntos
População do Leste Asiático , Miopia , Criança , Humanos , China/epidemiologia , Miopia/epidemiologia , Miopia/prevenção & controle , Estudos Prospectivos , Estudantes
2.
J Digit Imaging ; 36(2): 441-449, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36474087

RESUMO

Cervical cancer is the most common cancer among women worldwide. The diagnosis and classification of cancer are extremely important, as it influences the optimal treatment and length of survival. The objective was to develop and validate a diagnosis system based on convolutional neural networks (CNN) that identifies cervical malignancies and provides diagnostic interpretability. A total of 8496 labeled histology images were extracted from 229 cervical specimens (cervical squamous cell carcinoma, SCC, n = 37; cervical adenocarcinoma, AC, n = 8; nonmalignant cervical tissues, n = 184). AlexNet, VGG-19, Xception, and ResNet-50 with five-fold cross-validation were constructed to distinguish cervical cancer images from nonmalignant images. The performance of CNNs was quantified in terms of accuracy, precision, recall, and the area under the receiver operating curve (AUC). Six pathologists were recruited to make a comparison with the performance of CNNs. Guided Backpropagation and Gradient-weighted Class Activation Mapping (Grad-CAM) were deployed to highlight the area of high malignant probability. The Xception model had excellent performance in identifying cervical SCC and AC in test sets. For cervical SCC, AUC was 0.98 (internal validation) and 0.974 (external validation). For cervical AC, AUC was 0.966 (internal validation) and 0.958 (external validation). The performance of CNNs falls between experienced and inexperienced pathologists. Grad-CAM and Guided Gard-CAM ensured diagnoses interpretability by highlighting morphological features of malignant changes. CNN is efficient for histological image classification tasks of distinguishing cervical malignancies from benign tissues and could highlight the specific areas of concern. All these findings suggest that CNNs could serve as a diagnostic tool to aid pathologic diagnosis.


Assuntos
Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/diagnóstico por imagem , Redes Neurais de Computação , Colo do Útero
3.
Plant Reprod ; 35(3): 221-231, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35674836

RESUMO

It is widely known that an optimal nucleotide sequence context immediately upstream of the AUG start codon greatly improves the efficiency of translation initiation of mRNA in mammalian and plant somatic cells, which in turn increases protein levels. However, it is still unclear whether a similar regulatory mechanism is also present in highly differentiated cells. Here, we surveyed this issue in Arabidopsis thaliana sperm cells and found that the sequence context-mediated regulation of translation initiation in sperm cells is generally similar to that in somatic cells. A simple motif of four adenine nucleotides at positions - 1 to - 4 greatly improved the efficiency of translation initiation, and when the motif was present there, translation was even initiated at some non-AUG codons in sperm cells. However, unlike that in mammalian cells, a mainly effective nucleotide site to regulate the efficiency of translation initiation was not present at positions - 1 to - 4 in sperm cells. Meanwhile, different from somatic cells, sperm cells did not use eukaryotic translation initiation factor 1 to regulate the efficiency in a poor context consisting of the lowest frequency nucleotides. All these results contribute to our understanding of the cytoplasmic event of translation initiation in highly differentiated sperm cells.


Assuntos
Arabidopsis , Nucleotídeos , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Sequência de Bases , Códon de Iniciação/genética , Códon de Iniciação/metabolismo , Masculino , Mamíferos/genética , Mamíferos/metabolismo , Nucleotídeos/genética , Nucleotídeos/metabolismo , Biossíntese de Proteínas , Sementes/metabolismo , Espermatozoides/metabolismo
4.
Neoplasma ; 69(6): 1386-1395, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36591801

RESUMO

Breast cancer (BC) is a prevalent neoplasm that occurs in women all over the world. Growth and differentiation factor 11 (GDF11) plays an essential role in cancer progression. This study focused on investigating the biological role and underlying mechanisms of GDF11 in BC. We detected the expression of GDF11 in 27 patients with BC and BC cell lines. Kaplan-Meier plotter was employed to analyze the relationship between GDF11 expression and overall survival (OS) of BC patients. The proliferative, migratory, invasive, and apoptotic abilities of T47D cells were examined. Correlation analysis of GDF11 with Smad ubiquitination regulatory factor 1 (SMURF1) was conducted. The association between GDF11 and the p53 pathway was analyzed by western blot and PFT-α (a p53 inhibitor)-mediated rescue assays. A brief analysis of the role of estrogen receptor alpha (ERα) signaling in BC progression was performed. The results showed that GDF11 was increased in BC tissues and cell lines, and the high expression of GDF11 was associated with the poor OS of BC patients. GDF11 knockdown inhibited the proliferation, migration, and invasion of T47D cells, but promoted cell apoptosis. Meanwhile, the GDF11 knockdown reduced the SMURF1 expression and invoked the p53 pathway activation. SMURF1 overexpression and PFT-α partially blocked the effects of GDF11 knockdown. In addition, GDF11 knockdown and SMURF1 silencing inhibited the activation of the ERα signaling pathway. In summary, GDF11 was involved in the progression of BC by regulating SMURF1-mediated p53 and ERα pathways, opening up a new way for BC treatment.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/genética , Linhagem Celular Tumoral , Transdução de Sinais , Regulação Neoplásica da Expressão Gênica , Proliferação de Células , Proteínas Morfogenéticas Ósseas/metabolismo , Fatores de Diferenciação de Crescimento/genética , Fatores de Diferenciação de Crescimento/metabolismo
5.
Physiol Plant ; 173(3): 1179-1188, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34310717

RESUMO

Gene function studies benefit from the availability of mutants. In plants, Agrobacterium-mediated genetic transformation is widely used to create mutants. These mutants, also called transformants, contain one or several transfer-DNA (T-DNA) copies in the host genome. Quantifying the copy number of T-DNA in transformants is beneficial to assess the number of mutated genes. Here, we developed a competitive polymerase chain reaction (PCR)-based method to detect a single copy of a T-DNA insertion in transformants. The competitor line BHK- -1 that contains a single copy of competitor BHK- (BHK, Basta, Hygromycin, Kanamycin-resistant genes) was crossed with test transformants and the genomic DNA of F1 plants was subjected to competitive PCR. By analyzing the gray ratio between two PCR products, we were able to determine whether or not the test transformants contained a single copy of T-DNA insertion. We also generated the control lines BHK±1:1 and BHK±2:1 , which contain the target (BHK+ ) and competitor (BHK- ) in a ratio of 1:1 and 2:1, respectively. The ratios of their PCR products are useful references for quantitative analysis. Overall, this method is reliable and simple in experimental manipulations and can be used as a substitute for Southern-blot analysis to identify a single copy of T-DNA insertion in transformants.


Assuntos
DNA , DNA Bacteriano/genética , Reação em Cadeia da Polimerase , Transformação Genética
6.
Plant Physiol ; 185(1): 137-145, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33631800

RESUMO

The progression of the cell cycle is continuous in most cells, but gametes (sperm and egg cells) exhibit an arrest of the cell cycle to await fertilization to form a zygote, which then continues through the subsequent phases to complete cell division. The phase in which gametes of flowering plants arrest has been a matter of debate, since different phases have been reported for the gametes of different species. In this study, we reassessed the phase of cell-cycle arrest in the gametes of two species, Arabidopsis (Arabidopsis thaliana) and Torenia fournieri. We first showed that 4', 6-diamidino-2-phenylindole staining was not feasible to detect changes in gametic nuclear DNA in T. fournieri. Next, using 5-ethynyl-2'-deoxyuridine (EdU) staining that detects DNA replication by labeling the EdU absorbed by deoxyribonucleic acid, we found that the replication of nuclear DNA did not occur during gamete development but during zygote development, revealing that the gametes of these species have a haploid nuclear DNA content before fertilization. We thus propose that gametes in the G1 phase participate in the fertilization event in Arabidopsis and T. fournieri.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Replicação do DNA , Lamiales/crescimento & desenvolvimento , Lamiales/genética , Zigoto/crescimento & desenvolvimento , Zigoto/metabolismo , Arabidopsis/metabolismo , Variação Genética , Genótipo , Lamiales/metabolismo , Magnoliopsida/genética , Magnoliopsida/crescimento & desenvolvimento , Magnoliopsida/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo
7.
Anatol J Cardiol ; 19(3): 169-175, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29339676

RESUMO

OBJECTIVE: Hypertension is a significant risk factor for atrial fibrillation (AF). The role of pulmonary vein (PV) remodeling in the mechanistic association between hypertension and AF is not definitive. In this study, we aimed to identify changes in the electrophysiology and histology in PVs in two-kidney, one-clip (2K1C) hypertensive rats. METHODS: Fifty male Sprague-Dawley rats were classified into the 2K1C and sham-operated groups. The systolic blood pressure was measured every 2 weeks. The left atrial diameter was measured by transthoracic echocardiography. Left superior PV (LSPV) and left atrial (LA) fibrosis was evaluated by Masson's trichrome staining. The expression of fibrosis markers [angiotensin II (Ang II), transforming growth factor-ß1 (TGF-ß1), matrix metalloproteinase-2 (MMP-2), and collagen I (Col I)] and ion channels [Kir2.1, Kir2.3, Cav1.2, and Nav1.5] in LSVP was quantified by western blot. Conventional microelectrodes were used to record the action potential duration at 90% repolarization (APD90) and effective refractory period (ERP) in isolated LA. RESULTS: At 4 months, the 2K1C hypertensive rats developed LA dilation. Col deposition in LSPV and left atrium and expression of TGF-ß1, MMP-2, and Col I in LSPV were significantly increased in 2K1C hypertensive rats. In addition, hypertension reduced the expression of Nav1.5 and Kir2.1, although there were no significant differences in APD90; ERP; and expression of Ang II, Kir2.3, and Cav1.2 between the two groups. CONCLUSION: Hypertension may lead to changes in the electrophysiology and histology of rats PVs, which is characterized by significant reduction in the expression of Nav1.5 and Kir2.1 and increase in interstitial fibrosis. These observations may clarify the role of PVs in the mechanistic association between hypertension and AF.


Assuntos
Fibrilação Atrial , Hipertensão , Veias Pulmonares/diagnóstico por imagem , Animais , Modelos Animais de Doenças , Ecocardiografia , Técnicas Eletrofisiológicas Cardíacas , Fibrose/patologia , Masculino , Veias Pulmonares/patologia , Veias Pulmonares/fisiopatologia , Ratos , Ratos Sprague-Dawley
8.
Lipids Health Dis ; 15: 133, 2016 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-27544079

RESUMO

OBJECTIVES: To explore the possible role of n-3 polyunsaturated fatty acids (PUFAs) in lowering inflammation markers in individuals with type 2 diabetes mellitus. METHODS: PubMed, CNKI and Cochrane databases were searched until December 30, 2015; references from papers or reviews were also retrieved and screened. Screening was performed by two independent researchers, and randomized controlled trials reporting the specific n-3 PUFA type, dose, frequency, and duration of treatment, as well as the baseline and follow-up concentrations of inflammation markers, including interleukin 2 (IL-2), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α) and C-reactive protein (CRP), were selected for final analysis. Data analysis was performed using RevMan 5.2 software. RESULTS: Eight studies involving 955 participants were included; all reported CRP. Only one included study reported IL-2 or IL-6 while two studies reported TNF-α. N-3 PUFAs significantly reduced CRP concentration compared with control [SMD 95 % CI, 1.90 (0.64, 3.16), Z = 2.96, P = 0.003, random effect model]. CONCLUSIONS: N-3 PUFAs decrease CRP concentration in type-2 diabetes mellitus. However, larger and rigorously designed RCTs are required to confirm this finding and extend it into other inflammatory biomarkers.


Assuntos
Biomarcadores/sangue , Diabetes Mellitus Tipo 2/sangue , Ácidos Graxos Ômega-3/sangue , Inflamação/sangue , Proteína C-Reativa/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Humanos , Inflamação/complicações , Inflamação/patologia , Interleucina-2/sangue , Interleucina-6/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto , Fator de Necrose Tumoral alfa/sangue
9.
Cell Biochem Biophys ; 68(1): 189-94, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23733675

RESUMO

Crude extracts from ginseng demonstrated anti-obesity properties. Ginsenoside Rb1 is the main component of ginseng, however, there are only few studies examining its effects in obesity. In the present study, we evaluated its potential anti-obesity effects in the murine model of diet-induced obesity. Seventy male C57BL/6 mice were randomly divided to consume for 12 weeks either chow diet (N = 8) or high-fat (HF) diet (N = 62). The latter mice were then divided into four groups: diet-induced obesity group (DIO; N = 10), obesity-resistant group (OR; N = 10), HF group (N = 5), and the group whose diet was changed from HF to normal diet (DC; N = 5). Intraperitoneal injections of Rb-1 were administered daily to mice in the DIO and OR groups for 3 weeks. Body weight and energy intake were monitored, and fasting blood glucose, lipids, neuropeptide Y, Y2 receptor, and peptide YY were quantified. Compared with HF group, weight gain and food intake of DIO mice with Rb-1 injection was significantly decreased (p < 0.05). Further, levels of blood glucose and some lipids were also decreased in DIO-Rb1 group compared with HF group. Furthermore, Rb1 was also found to modulate serum levels of PYY and NPY, and mRNA expression of NPY, Y2 receptor and PYY in tissue samples of DIO mice. Taken together, ginsenoside Rb1 may be useful in the treatment of obesity via modifying the serum content and mRNA expression of NPY, Y2 receptor and PYY.


Assuntos
Peso Corporal/efeitos dos fármacos , Dieta , Ginsenosídeos/farmacologia , Panax/química , Animais , Glicemia/análise , Dieta Hiperlipídica , Esquema de Medicação , Ginsenosídeos/química , Ginsenosídeos/uso terapêutico , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Neuropeptídeo Y/sangue , Neuropeptídeo Y/genética , Neuropeptídeo Y/metabolismo , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Obesidade/patologia , Panax/metabolismo , Peptídeo YY/sangue , Peptídeo YY/genética , Peptídeo YY/metabolismo , Receptores de Neuropeptídeo Y/análise , Receptores de Neuropeptídeo Y/genética , Receptores de Neuropeptídeo Y/metabolismo
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