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PURPOSE: Targeted axillary dissection (TAD) after neoadjuvant therapy (NAT) includes removing of marked and sentinel lymph nodes (SLNs). The aim was to investigate the optimization of TAD localization techniques after NAT among breast cancer patients. METHODS: From November 2020 to 2022, we prospectively enrolled 107 lymph node-positive breast cancer patients in XX Hospital and received complete cycles of NAT. Patients were randomly divided into the following 3 groups before treatment: group A, marked node with clip (n=34); group B, marked node with 125I seed (n=32); and group C, marked node with clip and 125I seed (n=41). Dual tracers were used to search for SLNs after NAT. The main endpoint was the detection rate of marked nodes and false-negative rate (FNR). RESULTS: The detection rates using the TAD localization technique were 82.6% (28/34), 100% (32/32), and 100% (41/41) for groups A, B, and C, respectively (P>0.05). The FNR rates were 15.8%, 5.9%, and 5.6% among group A, B, and C, respectively (P>0.05). The FNR rates in cN1 patients were 5.1%, 2.7%, and 2.6%, among these three groups, respectively (P>0.05). The change in distance between 125I seeds and clips in axillary lymph nodes was <3 mm. The FNR rates of TAD guided by dye tracer, radiolabeled tracer, and dual tracers were 5.4%, 5.2%, and 3.4%, respectively (P>0.05). The negative predictive values were 93.0%, 93.0%, and 95.2%, respectively (P>0.05). CONCLUSION: Considering inexpensive and detect rate of 125I seeds, it is recommended that placement of 125I seeds to localize metastatic nodes in neoadjuvant setting. The TAD guided by dye tracer is also feasible for axillary de-escalation surgery after NAT in countries or regions without radiolabeled colloid.
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Background: The distant metastasis of lung cancer primarily occurs in the bones, liver, brain, and lungs, while the breast is an extremely rare site of metastasis. There is very limited literature on the occurrence of breast metastasis from lung cancer, and metastatic lesions in the breast are prone to being misdiagnosed as primary breast cancer, requiring careful attention and differentiation in the clinical diagnostic and treatment process. Case summary: The patient, a 63-year-old female, initially presented with an EGFR exon 21 L858R mutated left lung adenocarcinoma in 2017, treated successfully with surgical resection and subsequent monitoring. The relapse of disease occurred in January 2020. Despite maintaining a prolonged progression-free survival (PFS) with first-generation EGFR-TKI Afatinib, disease progression occurred in 2022 without detectable resistance mutations. Transition to second-generation TKI Furmonertinib resulted in poor control, with rapid progression including unusual bilateral breast metastases that exhibited inflammatory breast cancer-like peau d'orange changes. Standard chemotherapy achieved only short-term stability. Upon detecting a MET amplification mutation, treatment with Savolitinib was initiated. Remarkably, this led to significant clinical and radiographic improvement, notably resolving the peau d'orange appearance and reducing multiple lesions across the body. Conclusion: This case underscores the importance of continuous genetic profiling and tailored treatment approaches in managing advanced lung adenocarcinoma, particularly when presenting with rare metastatic sites and complex genetic landscapes. The successful application of Savolitinib following the identification of a MET amplification mutation highlights its potential in overcoming resistance mechanisms in NSCLC, providing a significant therapeutic option for similarly challenging cases.
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BACKGROUND: Gustilo III fractures have a high incidence and are difficult to treat. Patients often experience difficulty in wound healing. Negative pressure drainage technology can help shorten wound healing time and has positive value in improving patient prognosis. AIM: To explore the clinical value of the negative pressure sealing drainage technique in wound healing of Gustilo IIIB and IIIC open fractures. METHODS: Eighty patients with Gustilo IIIB and IIIC open fractures with skin and soft tissue injuries who were treated in the Second People's Hospital of Dalian from March 2019 to December 2021 were selected as the research subjects. They were divided into a study group (n = 40, healed with negative pressure closed drainage) and a control group (n = 40, healed with conventional dressing changes) according to the variation in the healing they received. The efficacy of the clinical interventions, the variations in the regression indicators (time to wound healing, time to fracture healing, time to hospitalization), and the conversion and healing of bacterial wounds were compared 1-3 mo after the intervention. RESULTS: The total effective rate of patients among the study group was 95.00% (38/40), which was notably higher than 75.00% (30/40) among the control group (P < 0.05). The wound healing time, fracture healing time, and hospital stay of the patients in the study group was shorter than the control group (P < 0.05). After the intervention, the negative bacterial culture at the wound site rate and wound healing rate of the patients among the study group increased compared to the control group (P < 0.05). CONCLUSION: Negative pressure sealing and drainage technology has a good therapeutic effect on patients with Gustilo IIIB and IIIC open fracture wounds with skin and soft tissue injury. It can notably enhance the wound healing rate and the negative rate of bacteria on the wound surface and help to speed up the recovery process of patients.
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Purpose: The purpose of this study was to provide advice for the indication of regional nodal irradiation (RNI) in patients with one to two positive sentinel lymph nodes (SLNs) without axillary lymph node dissection (ALND). Methods: We conducted a retrospective study in Shandong Cancer Hospital, Fudan University Shanghai Cancer Center, and West China Hospital. Logistic analysis was performed in order to explore the influencing factors of positive non-SLNs (NSLNs) and >3 positive nodes among patients with one to two SLNs+. Then, nomograms were constructed. Results: Between May 2010 and 2020, among the 2,845 patients with one to two SLNs+ undergoing ALND (1,992 patients in the training set and 853 patients in the validation set), there were 34.3% harbored NSLNs+ and 15.6% harbored >3 positive nodes. Multivariate analysis showed that cN stage, the number of positive/negative SLN, pathological tumor stage, lympho-vascular invasion (LVI), multicenter, and molecular subtypes were significantly associated with NSLN metastasis. Similarly, multivariate analysis also showed that cN stage, the number of positive/negative SLNs, pathological tumor stage, and LVI could be independent predictors of >3 positive nodes. Then, nomograms for NSLN metastasis and >3 positive nodes were constructed using these parameters, respectively. Conclusions: The nomograms will be useful in estimating positive NSLNs and >3 positive nodes, and they might provide advice for the optimization of RNI.
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Rural ecology is a comprehensive field of study that takes the rural social-ecological-economic systems as the objective object and emphasizes spatial carrier governance. The development of rural ecology in the New Era embodies and implements comprehensively the core concepts of Xi Jinping Thought on Socialism with Chinese Cha-racteristics for a New Era, including harmonious coexistence between humans and nature, rural revitalization, green development, and the comprehensive construction of a socialist modernized nation. Under the goal of Chinese-style modernization, rural ecology exhibits characteristics distinct from the past, such as the integration of research objects, the intersectionality of basic theories, the computational feature of technical methods, and the orientation of exporting outcomes. To provide disciplinary support for modernization-oriented science to meet the new demands of country's rural development, effectively narrating the story of sustainable rural development in China and providing fundamental guarantees for the safety of rural systems, a number of issues such as paradigm innovation in research, improvement of data quality, and integration of comprehensive technologies, should be fully considered.
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Ecologia , População Rural , Humanos , China , Ecossistema , Socialismo , Conservação dos Recursos NaturaisRESUMO
Most membrane proteins are modified by covalent addition of complex sugars through N- and O-glycosylation. Unlike proteins, glycans do not typically adopt specific secondary structures and remain very mobile, shielding potentially large fractions of protein surface. High glycan conformational freedom hinders complete structural elucidation of glycoproteins. Computer simulations may be used to model glycosylated proteins but require hundreds of thousands of computing hours on supercomputers, thus limiting routine use. Here, we describe GlycoSHIELD, a reductionist method that can be implemented on personal computers to graft realistic ensembles of glycan conformers onto static protein structures in minutes. Using molecular dynamics simulation, small-angle X-ray scattering, cryoelectron microscopy, and mass spectrometry, we show that this open-access toolkit provides enhanced models of glycoprotein structures. Focusing on N-cadherin, human coronavirus spike proteins, and gamma-aminobutyric acid receptors, we show that GlycoSHIELD can shed light on the impact of glycans on the conformation and activity of complex glycoproteins.
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Glicoproteínas , Simulação de Dinâmica Molecular , Humanos , Microscopia Crioeletrônica , Glicoproteínas/química , Glicosilação , Polissacarídeos/químicaRESUMO
Chlorothalonil (CTL) is widely used in agricultural production and antifoulant additive globally due to its broad spectrum and non-systemic properties, resulting in its widespread existence in foods, soil and water. Extensive evidence demonstrated that exposure to CTL induced adverse effects on organisms and in particular its reproductive toxicity has been attracted public concern. However, the influences of CTL on oocyte maturation is mysterious so far. In this study, we documented the toxic effects of CTL on oocyte in vitro maturation and the related underlying mechanisms. Exposure to CTL caused continuous activation of spindle assembly checkpoints (SAC) which in turn compromised meiotic maturation in mouse oocyte, featured by the attenuation of polar body extrusion (PBE). Detection of cytoskeletal dynamics demonstrated that CTL exposure weakened the acetylation level of α-tubulin and impaired meiotic spindle apparatus, which was responsible for the aberrant state of SAC. Meanwhile, exposure to CTL damaged the function of mitochondria, inducing the decline of ATP content and the elevation of reactive oxygen species (ROS), which thereby induced early apoptosis and DNA damage in mouse oocytes. In addition, exposure to CTL caused the alteration of the level of histone H3 methylation, indicative of the harmful effects of CTL on epigenetic modifications in oocytes. Further, the CTL-induced oxidative stress activated mitogen-activated protein kinase (MAPK) pathway and injured the maturation of oocytes. In summary, exposure to CTL damaged mouse oocyte in vitro maturation via destroying spindle assembly, inducing oxidative stress and triggering MAPK pathway activation.
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Técnicas de Maturação in Vitro de Oócitos , Proteínas Quinases Ativadas por Mitógeno , Nitrilas , Animais , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Estresse Oxidativo , Oócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , ApoptoseRESUMO
Propyl gallate (PG), owing to its exceptional antioxidant properties, is extensively used in industries such as food processing. The potential harmful impacts of PG have sparked concern among people. It has been reported that exposure of PG has certain reproductive toxicity, which can affect the maturation of mouse oocytes and induce testicular dysfunction. However, its impact on early embryonic development is still unclear. In this study, we explored the toxic effects and potential mechanisms of PG on mouse 2-cell stage embryonic development. The results showed that exposure of PG can decrease the development of 2-cell stage embryos and repress the development of 4-cell stage embryos. Further study found that PG could induce intracellular oxidative stress and the accumulation of DNA damage in 2-cell stage embryos. Moreover, exposure of PG impaired the function of mitochondria and lysosomes in 2-cell stage embryos, thereby triggering the occurrence of autophagy. In addition, exposure of PG altered the epigenetic modification of 2-cell stage embryos, displaying a decreased level of DNA methylation and an increased level of H3K4me3. In summary, our results indicated that exposure of PG can damage the development of mouse 2-cell stage embryos by inducing oxidative stress, DNA damage, and autophagy, and altering epigenetic modification.
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Estresse Oxidativo , Galato de Propila , Gravidez , Feminino , Humanos , Animais , Camundongos , Galato de Propila/toxicidade , Antioxidantes/toxicidade , Autofagia , Desenvolvimento EmbrionárioRESUMO
BACKGROUND: Obstructive sleep apnea-hypopnea syndrome (OSAHS) is primarily caused by airway obstruction due to narrowing and blockage in the nasal and nasopharyngeal, oropharyngeal, soft palate, and tongue base areas. The mid-frequency anti-snoring device is a new technology based on sublingual nerve stimulation. Its principle is to improve the degree of oropharyngeal airway stenosis in OSAHS patients under mid-frequency wave stimulation. Nevertheless, there is a lack of clinical application and imaging evidence. AIM: To investigate the clinical efficacy and mechanisms of a mid-frequency anti-snoring device in treating moderate OSAHS. METHODS: We selected 50 patients diagnosed with moderate OSAHS in our hospital between July 2022 and August 2023. They underwent a 4-wk treatment regimen involving the mid-frequency anti-snoring device during nighttime sleep. Following the treatment, we monitored and assessed the sleep apnea quality of life index and Epworth Sleepiness Scale scores. Additionally, we performed computed tomography scans of the oropharynx in the awake state, during snoring, and while using the mid-frequency anti-snoring device. Cross-sectional area measurements in different states were taken at the narrowest airway point in the soft palate posterior and retrolingual areas. RESULTS: Compared to pretreatment measurements, patients exhibited a significant reduction in the apnea-hypopnea index, the percentage of time with oxygen saturation below 90%, snoring frequency, and the duration of the most prolonged apnea event. The lowest oxygen saturation showed a notable increase, and both sleep apnea quality of life index and Epworth Sleepiness Scale scores improved. Oropharyngeal computed tomography scans revealed that in OSAHS patients cross-sectional areas of the oropharyngeal airway in the soft palate posterior area and retrolingual area decreased during snoring compared to the awake state. Conversely, during mid-frequency anti-snoring device treatment, these areas increased compared to snoring. CONCLUSION: The mid-frequency anti-snoring device demonstrates the potential to enhance various sleep parameters in patients with moderate OSAHS, thereby improving their quality of life and reducing daytime sleepiness. These therapeutic effects are attributed to the device's ability to ameliorate the narrowing of the oropharynx in OSAHS patients.
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A mutant of ubiquitin C-terminal hydrolase L1 (UCHL1) detected in early-onset neurodegenerative patients, UCHL1R178Q, showed higher catalytic activity than wild-type UCHL1 (UCHL1WT). Lying within the active-site pocket, the arginine is part of an interaction network that holds the catalytic histidine in an inactive arrangement. However, the structural basis and mechanism of enzymatic activation upon glutamine substitution was not understood. We combined X-ray crystallography, protein nuclear magnetic resonance (NMR) analysis, enzyme kinetics, covalent inhibition analysis, and biophysical measurements to delineate activating factors in the mutant. While the crystal structure of UCHL1R178Q showed nearly the same arrangement of the catalytic residues and active-site pocket, the mutation caused extensive alteration in the chemical environment and dynamics of more than 30 residues, some as far as 15 Å away from the site of mutation. Significant broadening of backbone amide resonances in the HSQC spectra indicates considerable backbone dynamics changes in several residues, in agreement with solution small-angle X-ray scattering (SAXS) analyses which indicate an overall increase in protein flexibility. Enzyme kinetics show the activation is due to a kcat effect despite a slightly weakened substrate affinity. In line with this, the mutant shows a higher second-order rate constant (kinact/Ki) in a reaction with a substrate-derived irreversible inhibitor, Ub-VME, compared to the wild-type enzyme, an observation indicative of a more reactive catalytic cysteine in the mutant. Together, the observations underscore structural plasticity as a factor contributing to enzyme kinetic behavior which can be modulated through mutational effects.
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Domínio Catalítico , Cisteína , Doenças Neurodegenerativas , Ubiquitina Tiolesterase , Humanos , Sítios de Ligação/genética , Cisteína/química , Cisteína/genética , Cinética , Mutagênese Sítio-Dirigida , Ressonância Magnética Nuclear Biomolecular , Espalhamento a Baixo Ângulo , Ubiquitina Tiolesterase/química , Ubiquitina Tiolesterase/genética , Difração de Raios X , Doenças Neurodegenerativas/genéticaRESUMO
Epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) is clinically and genetically heterogeneous, with concurrent RB1/TP53 mutations, indicating an increased risk of transformation into small cell lung cancer (SCLC). When tumor cells convert into a different histological subtype, they lose their dependence on the original oncogenic driver, resulting in therapeutic resistance. However, the molecular details associated with this transformation remain unclear. It has been difficult to define molecular mechanisms of neuroendocrine (NE) transformation in lung cancer due to a lack of pre- and post-transformation clinical samples. In this study, we established a NSCLC cell line with concurrent RB1/TP53 mutations and built corresponding patient-derived xenograft (PDX) models to investigate the mechanisms underlying transformation to SCLC. Studying these PDX models, we demonstrate that EGFR loss facilitates lineage plasticity of lung adenocarcinoma initiated by biallelic mutations of TP53 and RB1. Gene expression analysis of these EGFR knockout tumors revealed altered expression of neuroendocrine synapse-associated lineage genes. There is an increased expression of epigenetic reprogramming factors like Sox2 and gene associated with neural development like NTRK in these EGFR knockout tumors. These findings uncovered the role of EGFR in the acquisition of plasticity, which is the ability of a cell to substantially modify its identity and take on a new phenotype, and defined a novel landscape of potential drivers of NE transformation in lung cancer.
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Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Receptores ErbB , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Adenocarcinoma de Pulmão/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Neoplasias Pulmonares/patologia , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Carcinoma de Pequenas Células do Pulmão/patologia , AnimaisRESUMO
OBJECTIVE: Internal mammary nodes are important in breast cancer prognosis, but their diagnosis is often missed in clinical practice, leading to inaccurate staging and treatment. We developed a validated nomogram to predict the presence of internal mammary sentinel nodes (IMSN) metastasis. METHODS: A total of 864 sequential IMSN biopsy procedures from a prospective studies database of 1505 cases were used for model development and validation. Multivariable logistic regression was performed on 519 sequential IMSN biopsy procedures from multi-center data between August 2018 and July 2022 to predict the presence of IMSN metastasis. A nomogram was developed based on the logistic regression model and subsequently applied to 345 sequential IMSN biopsy procedures from single-center data between November 2011 and July 2018. The model's discrimination was assessed using the area under the receiver operating characteristic curve. RESULTS: The overall frequency of IMSN metastasis was 17.0% in our study. A predictive model for IMSN metastasis was constructed using tumor size, tumor location, lymphovascular invasion, the number of positive axillary nodes (P < 0.05 for all variables in multivariate analysis), and histological grade (P < 0.05 only in univariate analysis). The nomogram was accurate, with a concordance index of 0.84 in the bootstrapping analysis and an area under the receiver operating characteristic curve of 0.80 in the validation population. CONCLUSION: Our nomogram provides an accurate and validated multivariable predictive model for estimating the individual likelihood of having IMSN metastasis. This may be useful for personalized treatment decisions regarding internal mammary radiotherapy in breast cancer patients.
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Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/cirurgia , Nomogramas , Metástase Linfática/patologia , Estudos Prospectivos , Linfonodos/patologia , Biópsia de Linfonodo SentinelaRESUMO
Bisphenol AF (BPAF), a BPA-substitute, has been widely used in industrial compounds throughout the world. Several studies have shown that BPAF has endocrine interference and reproductive toxicity. However, the toxic effects of BPAF on pregnancy and placenta of goats are still unclear. Therefore, the objective of this study was to reveal the toxic effect of BPAF by using an in vitro culture model of caprine endometrial epithelial cells (EECs) and further attempted to alleviate the toxicity by curcumin pretreatment. The results showed that BPAF induces significant effects on EECs, including decreased cell viability and mitochondrial membrane potential (â³ψm), elevating intracellular reactive oxygen species (ROS), promoting cell apoptosis through upregulating the expression of Bax, Cytochrome c, and downregulating the expression of Bcl-2. Meanwhile, BPAF induced dysregulation of oxidative stress by increasing the levels of malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) but decreasing the activities of superoxide dismutase (SOD). However, curcumin pretreatment could significantly attenuate BPAF-induced toxic effects in EECs. Further study revealed that BPAF treatment could activate mitogen-activated protein kinase (MAPK) pathway and nuclear factor-erythroid 2-related factor 2 (Nrf2) expression, but curcumin pretreatment significantly inhibited the activation of MAPK signal pathway and Nrf2 expression induced by BPAF. Overall, this study indicated that curcumin could prevent BPAF-induced EECs cytotoxicity, which provides a potential therapeutic strategy for female infertility associated with BPAF exposure.
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Curcumina , Animais , Feminino , Curcumina/farmacologia , Fator 2 Relacionado a NF-E2 , Cabras , Estresse Oxidativo , Transdução de Sinais , Proteínas Quinases Ativadas por Mitógeno , Células Epiteliais , ApoptoseRESUMO
The intracellular phosphatase domain of the receptor-type protein tyrosine phosphatase alpha (PTPRA) is known to regulate various signaling pathways related to cell adhesion through c-Src kinase activation. In contrast, the functional significance of its relatively short, intrinsically disordered, and heavily glycosylated ectodomain remains unclear. Through detailed mass spectrometry analyses of a combination of protease and glycosidase digests, we now provide the first experimental evidence for its site-specific glycosylation pattern. This includes the occurrence of O-glycan at the N-glycosylation sequon among the more than 30 O-glycosylation sites confidently identified beside the 7 N-glycosylation sites. The closely spaced N- and O-glycans appear to have mutually limited the extent of further galactosylation and sialylation. An immature smaller form of full-length PTPRA was found to be deficient in O-glycosylation, most likely due to failure to transit the Golgi. N-glycosylation, on the other hand, is dispensable for cell surface expression and contributes less than the extensive O-glycosylation to the overall solution structure of the ectodomain. The glycosylation information is combined with the overall structural features of the ectodomain derived from small-angle X-ray scattering and high-speed atomic force microscopy monitoring to establish a dynamic structural model of the densely glycosylated PTPRA ectodomain. The observed high structural flexibility, as manifested by continuous transitioning from fully to partially extended and fold-back conformations, suggests that the receptor-type phosphatase is anchored to the membrane and kept mostly at a monomeric state through an ectodomain shaped and fully shielded by glycosylation.
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OBJECTIVE: The available evidence on selenium supplementation in the treatment of autoimmune thyroiditis (AIT) was inconclusive. This research serves to assess the effects of selenium supplementation in the treatment of AIT. METHODS: Online databases including PubMed, Web of Science, Embase, and the Cochrane Library were searched from inception to 10 June 2022. The AMSTAR-2 tool was used to assess the methodological quality of included studies. The information on the randomized controlled trials of the included studies was extracted and synthesized. The GRADE system was used to assess the certainty of evidence. RESULTS: A total of 6 systematic reviews with 75 RCTs were included. Only one study was rated as high quality. The meta-analysis showed that in the levothyroxine (LT4)-treated population, thyroid peroxidase antibody (TPO-Ab) levels decreased significantly in the selenium group at 3 months (SMD = -0.53, 95% CI: [-0.89, -0.17], p < 0.05, very low certainty) and 6 months (SMD = -1.95, 95% CI: [-3.17, -0.74], p < 0.05, very low certainty) and that thyroglobulin antibody (Tg-Ab) levels were not decreased. In the non-LT4-treated population, TPO-Ab levels decreased significantly in the selenium group at 3 and 6 months and did not decrease at 12 months. Tg-Ab levels decreased significantly in the selenium group at 3 and 6 months and did not decrease at 12 months. The adverse effects reported in the selenium group were not significantly different from those in the control group, and the certainty of evidence was low. CONCLUSION: Although selenium supplementation might reduce TPO-Ab levels at 3 and 6 months and Tg-Ab levels at 3 and 6 months in the non-LT4-treated population, this was based on a low certainty of evidence.
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Doença de Hashimoto , Selênio , Tireoidite Autoimune , Humanos , Tireoidite Autoimune/tratamento farmacológico , Selênio/uso terapêutico , Iodeto Peroxidase , Revisões Sistemáticas como Assunto , Tiroxina , Suplementos NutricionaisRESUMO
Propyl gallate (PG) is one of the most widely used antioxidants in food products, cosmetics and pharmaceutical industries. Increased research has suggested that exposure to PG influences reproductive health in humans and animals. However, until now, it has not yet been confirmed whether PG would impact oocyte quality. In this study, the hazardous effects of PG on oocyte meiotic maturation were investigated in mice. The findings showed that PG exposure compromises oocyte meiosis by inducing mitochondrial stress which activates apoptosis to trigger oocyte demise. Moreover, DNA damage was significantly induced in PG-treated oocytes, which might be another cause of oocyte developmental arrest and degeneration. Besides, the level of histone methylation (H3K27me2 and H3K27me3) in oocyte was also significantly increased by PG exposure. Furthermore, PG-induced oxidative stress was validated by the increased level of reactive oxygen species (ROS), which might be the underlying reason for these abnormities. In conclusion, the foregoing findings suggested that PG exposure impaired oocyte meiotic maturation by yielding mitochondrial stress to activate apoptosis, inducing DNA damage and oxidative stress, and altering histone methylation level.
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Antioxidantes , Galato de Propila , Humanos , Animais , Camundongos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Galato de Propila/metabolismo , Galato de Propila/farmacologia , Histonas , Oócitos , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo , Meiose , Dano ao DNA , ApoptoseRESUMO
Improving ecosystem quality and stability is one of the urgent tasks of national ecological environment construction. However, the ecological theory of ecosystem quality and stability has not been well clarified. Based on the summary of influencing factors and interaction between ecosystem quality and stability, we discussed the ecolo-gical theory on the evolution of ecosystem quality and stability from the perspectives of self-organization of biological agglomeration and structure nesting, correlation of ecological elements and coupling of ecological processes, ecosystem integrity and function emergence, ecological service spillover and efficiency tradeoff, synergy and interactions between resource supply capacity and environmental suitability, as well as interactions between spontaneous change and human activities. Technologies approaches and management strategies were proposed from the aspects of ecosystem macro-pattern adjustment, protected natural areas system construction, regional complex ecosystem comprehensive management, degraded ecosystem restoration, damaged ecosystem reestablishment, typical ecosystem process management.