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1.
J Cell Physiol ; 236(7): 4944-4953, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33368268

RESUMO

Obesity causes many reproductive dysfunctions such as reduced conception, infertility, and early pregnancy loss, and this is largely due to the negative effects of obesity on oocyte and embryo quality. In the present study, we employed single-cell RNA transcriptome sequencing to investigate the potential causes for the maternal obesity effects on mouse embryos. Our results showed that the 4-cell and morula/blastocyst rates were all significantly decreased during embryo development in obese mice. Genome-wide analysis indicated that obesity altered the expression of more than 1100 genes in 2-cell embryos, including the genes which were related to the p53 signaling pathway and apoptosis. Further analysis showed that the expression of 47 genes related to DNA damage was changed, and a positive γH2A signal and the altered expression of Rad51 and Tex15 were observed in the obese embryos. Obesity also affected histone methylation, shown by the decrease of the H3K4-me2 level. Besides this, we observed the occurrence of autophagy and apoptosis in the embryos of obese mice. There were 42 genes that were related to autophagy/apoptosis that showed aberrant expression, and the positive LC3 signal and the decrease of Clec16a, Rraga, and Atg10 level were also observed. In summary, our study suggested that obesity affected early embryonic development by inducing DNA damage, aberrant histone methylation, and autophagy levels in mice.


Assuntos
Autofagia/fisiologia , Metilação de DNA/genética , Reparo do DNA/genética , Desenvolvimento Embrionário/fisiologia , Obesidade Materna/patologia , Animais , Apoptose/fisiologia , Blastocisto/fisiologia , Proteínas de Ciclo Celular/biossíntese , Desenvolvimento Embrionário/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Oócitos/citologia , Gravidez , Rad51 Recombinase/biossíntese , Análise de Célula Única , Transcriptoma
2.
BMC Infect Dis ; 21(1): 1145, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34753451

RESUMO

BACKGROUND: The global spread of the novel coronavirus pneumonia is still continuing, and a new round of more serious outbreaks has even begun in some countries. In this context, this paper studies the dynamics of a type of delayed reaction-diffusion novel coronavirus pneumonia model with relapse and self-limiting treatment in a temporal-spatial heterogeneous environment. METHODS: First, focus on the self-limiting characteristics of COVID-19, incorporate the relapse and self-limiting treatment factors into the diffusion model, and study the influence of self-limiting treatment on the diffusion of the epidemic. Second, because the traditional Lyapunov stability method is difficult to determine the spread of the epidemic with relapse and self-limiting treatment, we introduce a completely different method, relying on the existence conditions of the exponential attractor of our newly established in the infinite-dimensional dynamic system to determine the diffusion of novel coronavirus pneumonia. Third, relapse and self-limiting treatment have led to a change in the structure of the delayed diffusion COVID-19 model, and the traditional basic reproduction number [Formula: see text] no longer has threshold characteristics. With the help of the Krein-Rutman theorem and the eigenvalue method, we studied the threshold characteristics of the principal eigenvalue and found that it can be used as a new threshold to describe the diffusion of the epidemic. RESULTS: Our results prove that the principal eigenvalue [Formula: see text] of the delayed reaction-diffusion COVID-19 system with relapse and self-limiting treatment can replace the basic reproduction number [Formula: see text] to describe the threshold effect of disease transmission. Combine with the latest official data and the prevention and control strategies, some numerical simulations on the stability and global exponential attractiveness of the diffusion of the COVID-19 epidemic in China and the USA are given. CONCLUSIONS: Through the comparison of numerical simulations, we find that self-limiting treatment can significantly promote the prevention and control of the epidemic. And if the free activities of asymptomatic infected persons are not restricted, it will seriously hinder the progress of epidemic prevention and control.


Assuntos
COVID-19 , Epidemias , Número Básico de Reprodução , Humanos , Modelos Biológicos , SARS-CoV-2
3.
Chaos Solitons Fractals ; 143: 110546, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33519115

RESUMO

As the COVID-19 epidemic has entered the normalization stage, the task of prevention and control remains very arduous. This paper constructs a time delay reaction-diffusion model that is closer to the actual spread of the COVID-19 epidemic, including relapse, time delay, home quarantine and temporal-spatial heterogeneous environment that affect the spread of COVID-19. These factors increase the number of equations and the coupling between equations in the system, making it difficult to apply the methods commonly used to discuss global dynamics, such as the Lyapunov function method. Therefore, we use the global exponential attractor theory in the infinite-dimensional dynamic system to study the spreading trend of the COVID-9 epidemic with relapse, time delay, home quarantine in a temporal-spatial heterogeneous environment. Using our latest results of global exponential attractor theory, the global asymptotic stability and the persistence of the COVID-19 epidemic are discussed. We find that due to the influence of relapse in the in temporal-spatial heterogeneity environment, the principal eigenvalue λ * can describe the spread of the epidemic more accurately than the usual basic reproduction number R 0 . That is, the non-constant disease-free equilibrium is globally asymptotically stable when λ * < 0 and the COVID-19 epidemic is persisting uniformly when λ * > 0 . Combine with the latest official data of the COVID-19 and the prevention and control strategies of different countries, some numerical simulations on the stability and global exponential attractiveness of the spread of the COVID-19 epidemic in China and the USA are given. The simulation results fully reflect the impact of the temporal-spatial heterogeneous environment, relapse, time delay and home quarantine strategies on the spread of the epidemic, revealing the significant differences in epidemic prevention strategies and control effects between the East and the West. The results of this study provide a theoretical basis for the current epidemic prevention and control.

4.
J Cell Physiol ; 234(6): 7847-7855, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30536398

RESUMO

Obesity and diabetes are closely associated with numerous reproductive disorders, including termination of ovulation, irregular menstruation, low fertility, abortion, and risky pregnancy, which are now regarded as global health problems. Paternal/maternal obesity and diabetes can also be transmitted to the subsequent generation via gametes, suggesting the association of epigenetic inheritance with obesity and diabetes, particularly for its effects on offspring. Recent studies indicate that both obesity and diabetes change DNA and histone methylation levels, histone acetylation, and noncoding RNAs such as microRNAs (miRNAs) in oocytes and sperm. Several important genes, such as PPAR-α, Igf2, H19, Fyn, Stella, Sirt3, Sirt6, and Peg3 as well as miRNAs, such as let-7c, reportedly participate in the regulation of epigenetic modifications in mammalian gametes. This review summarizes the recent progress that links obesity/diabetes and reproductive disorders from the perspective of gamete epigenetic modifications.


Assuntos
Diabetes Mellitus/genética , Células Germinativas/metabolismo , Código das Histonas/genética , Obesidade/genética , Animais , Metilação de DNA/genética , Diabetes Mellitus/patologia , Epigênese Genética/genética , Feminino , Células Germinativas/crescimento & desenvolvimento , Humanos , Masculino , Obesidade/patologia , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Espermatozoides/crescimento & desenvolvimento , Espermatozoides/metabolismo
6.
Toxicol Appl Pharmacol ; 300: 70-76, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-26988607

RESUMO

Deoxynivalenol (DON) is a widespread trichothecene mycotoxin which contaminates agricultural staples and elicits a complex spectrum of toxic effects on humans and animals. It has been shown that DON impairs oocyte maturation, reproductive function and causes abnormal fetal development in mammals; however, the mechanisms remain unclear. In the present study, we investigate the possible reasons of the toxic effects of DON on porcine oocytes. Our results showed that DON significantly inhibited porcine oocyte maturation and disrupted meiotic spindle by reducing p-MAPK protein level, which caused retardation of cell cycle progression. In addition, up-regulated LC3 protein expression and aberrant Lamp2, LC3 and mTOR mRNA levels were observed with DON exposure, together with Annexin V-FITC staining assay analysis, these results indicated that DON treatment induced autophagy/apoptosis in porcine oocytes. We also showed that DON exposure increased DNA methylation level in porcine oocytes through altering DNMT3A mRNA levels. Histone methylation levels were also changed showing with increased H3K27me3 and H3K4me2 protein levels, and mRNA levels of their relative methyltransferase genes, indicating that epigenetic modifications were affected. Taken together, our results suggested that DON exposure reduced porcine oocytes maturation capability through affecting cytoskeletal dynamics, cell cycle, autophagy/apoptosis and epigenetic modifications.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Tricotecenos/farmacologia , Animais , Ciclo Celular , Metilação de DNA/efeitos dos fármacos , Epigênese Genética , Feminino , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Suínos , Regulação para Cima
7.
Arch Toxicol ; 90(6): 1495-505, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26138683

RESUMO

T-2 toxin is one of the type A trichothecene mycotoxins that is considered to be the most toxic of the trichothecenes. T-2 toxin has been shown to exert various toxic effects in farm animals and humans, as it induces lesions in the brain and in lymphoid, hematopoietic, and gastrointestinal tissues. HT-2 toxin is the major metabolite of T-2 toxin. There is little information regarding the effects of HT-2 toxin on the female reproductive system, particularly oocyte maturation. Thus, in this study, we investigated the toxic effects of HT-2 on mouse oocyte maturation and its possible mechanisms of action. HT-2 toxin exposure disrupted oocyte maturation, reduced actin expression in both the oocyte cortex and cytoplasm, and disrupted meiotic spindle morphology by reducing p-MAPK protein level. HT-2 toxin exposure also induced oxidative stress and resulted in oocyte apoptosis, as shown by ROS accumulation, increased SOD mRNA level, and the expression of the early apoptosis marker Annexin V and increased caspase-3 and bax mRNA levels. Additionally, HT-2 toxin exposure increased LC3 and ATG12 protein levels and lc3 and atg14 mRNA levels, which indicated that HT-2 toxin induced autophagy in mouse oocytes. We also examined for possible epigenetic modifications. Fluorescence intensity analysis showed that 5mC level increased after HT-2 toxin exposure, whereas H3K9me2 and H3K27me3 levels decreased after HT-2 toxin exposure, which indicated that DNA and histone methylations were altered. Thus, our results indicated that HT-2 toxin exposure reduced mouse oocyte maturation capability by affecting cytoskeletal dynamics, apoptosis/autophagy, oxidative stress, and epigenetic modifications.


Assuntos
Oócitos/efeitos dos fármacos , Fuso Acromático/efeitos dos fármacos , Toxina T-2/análogos & derivados , Actinas/genética , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Técnicas In Vitro , Camundongos Endogâmicos ICR , Microscopia Confocal , Microscopia de Fluorescência , Oócitos/metabolismo , Oócitos/patologia , Estresse Oxidativo/efeitos dos fármacos , Fuso Acromático/metabolismo , Fuso Acromático/patologia , Toxina T-2/toxicidade
9.
Environ Toxicol ; 30(10): 1226-33, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24733567

RESUMO

Zearalenone (ZEN) is a metabolite of Fusarium and is a common contaminant of grains and foodstuffs. ZEN acts as a xenoestrogen and is considered to be cytotoxic, tissue toxic, and genotoxic, which causes abortions and stillbirths in humans and animals. Since estrogens affect oocyte maturation during meiosis, in this study we investigated the effects of ZEN on mouse oocyte meiotic maturation and granulosa cell proliferation. Our results showed that ZEN-treated oocyte maturation rates were decreased, which might be due to the disrupted cytoskeletons: (1) ZEN treatment resulted in significantly more oocytes with abnormal spindle morphologies; (2) actin filament expression and distribution were also disrupted after ZEN treatment, which was confirmed by the aberrant distribution of actin regulatory proteins. In addition, cortical granule-free domains (CGFDs) were disrupted after ZEN treatment, which indicated that ZEN may affect mouse oocyte fertilization capability. ZEN reduced mouse granulosa cell proliferation in a dose-dependent manner as determined by MTT assay and TUNEL apoptosis analysis, which may be another cause for the decreased oocyte maturation. Thus, our results demonstrated that exposure to zearalenone affected oocyte meiotic maturation and granulosa cell proliferation in mouse.


Assuntos
Proliferação de Células/efeitos dos fármacos , Meiose/efeitos dos fármacos , Zearalenona/toxicidade , Actinas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Feminino , Fusarium/química , Fusarium/metabolismo , Células da Granulosa/citologia , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Oócitos/citologia , Oócitos/efeitos dos fármacos
10.
Mutagenesis ; 29(6): 489-95, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25155023

RESUMO

Zearalenone (ZEA) is a mycotoxin produced by various Fusarium fungi, which has been shown to cause several cases of mycotoxicosis in farm animals and humans. However, there is no evidence regarding the effect of ZEA on mouse egg developmental competence. In this study, we found that the activation rate of maturated oocytes was affected in mice by ZEA treatment, indicating that ZEA affects egg developmental competence. And we explored possible mechanisms of low mouse maturated oocyte developmental competence after ZEA treatment from an epigenetic modification perspective. The fluorescence intensity analysis showed that 5-methyl cytosine level increased after ZEA treatment, indicating that the general DNA methylation level increased in the treated eggs. Moreover, histone methylations were also altered: H3K4me2 as well as H3K9me3 and H4K20me1, me2, me3 levels decreased in eggs that were cultured in high-dose ZEA medium. Thus, our results indicated that ZEA decreased egg developmental competence by affecting the epigenetic modifications.


Assuntos
Epigênese Genética/efeitos dos fármacos , Óvulo/metabolismo , Zearalenona/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Feminino , Histonas/metabolismo , Humanos , Lisina/metabolismo , Camundongos Endogâmicos ICR , Óvulo/efeitos dos fármacos
11.
Microsc Microanal ; 20(4): 1158-66, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24810297

RESUMO

Mycotoxins, such as aflatoxin (AF), fumonisin B1, zearalenone (ZEA), and deoxynivalenol (DON), are commonly found in many food commodities. Mycotoxins have been shown to increase DNA methylation levels in a human intestinal cell line. We previously showed that the developmental competence of oocytes was affected in mice that had been fed a mycotoxin-containing diet. In this study, we explored possible mechanisms of low mouse oocyte developmental competence after mycotoxin treatment in an epigenetic modification perspective. Mycotoxin-contaminated maize (DON at 3,875 µg/kg, ZEA at 1,897 µg/kg, and AF at 806 µg/kg) was included in diets at three different doses (mass percentage: 0, 15, and 30%) and fed to mice for 4 weeks. The fluorescence intensity analysis showed that the general DNA methylation levels increased in oocytes from high dose mycotoxin-fed mice. Mouse oocyte histone methylation was also altered. H3K9me3 and H4K20me3 level increased in oocytes from mycotoxin-fed mice, whereas H3K27me3 and H4K20me2 level decreased in oocytes from mycotoxin-fed mice. Thus, our results indicate that naturally occurring mycotoxins have effects on epigenetic modifications in mouse oocytes, which may be one of the reasons for reduced oocyte developmental competence.


Assuntos
Epigênese Genética/efeitos dos fármacos , Microscopia de Fluorescência , Micotoxinas/toxicidade , Oócitos/efeitos dos fármacos , Ração Animal , Animais , DNA/metabolismo , Metilação de DNA , Dieta/métodos , Histonas/metabolismo , Camundongos , Micotoxinas/administração & dosagem , Processamento de Proteína Pós-Traducional
12.
Curr Med Sci ; 44(2): 406-418, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619681

RESUMO

OBJECTIVE: Uterine corpus endometrial carcinoma (UCEC), a kind of gynecologic malignancy, poses a significant risk to women's health. The precise mechanism underlying the development of UCEC remains elusive. Zinc finger protein 554 (ZNF554), a member of the Krüppel-associated box domain zinc finger protein superfamily, was reported to be dysregulated in various illnesses, including malignant tumors. This study aimed to examine the involvement of ZNF554 in the development of UCEC. METHODS: The expression of ZNF554 in UCEC tissues and cell lines were examined by qRT-PCR and Western blot assay. Cells with stably overexpressed or knocked-down ZNF554 were established through lentivirus infection. CCK-8, wound healing, and Transwell invasion assays were employed to assess cell proliferation, migration, and invasion. Propidium iodide (PI) staining combined with fluorescence-activated cell sorting (FACS) flow cytometer was utilized to detect cell cycle distribution. qRT-PCR and Western blotting were conducted to examine relative mRNA and protein levels. Chromatin immunoprecipitation assay and luciferase reporter assay were used to explore the regulatory role of ZNF554 in RNA binding motif 5 (RBM5). RESULTS: The expression of ZNF554 was found to be reduced in both UCEC samples and cell lines. Decreased expression of ZNF554 was associated with higher tumor stage, decreased overall survival, and reduced disease-free survival in UCEC. ZNF554 overexpression suppressed cell proliferation, migration, and invasion, while also inducing cell cycle arrest. In contrast, a decrease in ZNF554 expression resulted in the opposite effect. Mechanistically, ZNF554 transcriptionally regulated RBM5, leading to the deactivation of the Wingless (WNT)/ß-catenin signaling pathway. Moreover, the findings from rescue studies demonstrated that the inhibition of RBM5 negated the impact of ZNF554 overexpression on ß-catenin and p-glycogen synthase kinase-3ß (p-GSK-3ß). Similarly, the deliberate activation of RBM5 reduced the increase in ß-catenin and p-GSK-3ß caused by the suppression of ZNF554. In vitro experiments showed that ZNF554 overexpression-induced decreases in cell proliferation and migration were counteracted by RBM5 knockdown. Additionally, when RBM5 was overexpressed, it hindered the improvements in cell proliferation and migration caused by reducing the ZNF554 levels. CONCLUSION: ZNF554 functions as a tumor suppressor in UCEC. Furthermore, ZNF554 regulates UCEC progression through the RBM5/WNT/ß-catenin signaling pathway. ZNF554 shows a promise as both a prognostic biomarker and a therapeutic target for UCEC.


Assuntos
Neoplasias do Endométrio , Via de Sinalização Wnt , Feminino , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Neoplasias do Endométrio/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Supressoras de Tumor/genética , Via de Sinalização Wnt/genética
13.
Cureus ; 15(6): e40473, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37333044

RESUMO

Knee osteoarthritis affects millions of people worldwide. There remains a role for novel therapies to manage pain for patients who are unable or unwilling to undergo knee arthroplasty. A peripheral nerve stimulator (PNS) may be beneficial in this population. We present a case report of three patients who received temporary femoral or saphenous PNS and were either unwilling or unable to undergo knee arthroplasty. Two of the three patients reported significantly reduced pain and improved functioning. Our case report demonstrates that temporary PNS may offer a safe and effective treatment for chronic knee pain secondary to knee osteoarthritis.

14.
Parasitol Res ; 109(2): 369-78, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21344211

RESUMO

Cysteine proteases, a superfamily of hydrolytic enzymes, have numerous functions in parasites. Here, we reported the cloning and characterization of a cDNA encoding a cathepsin B (AcCPB) from Angiostrongylus cantonensis fourth-stage larvae cDNA library. The deduced amino acid sequence analysis indicated AcCPB is related to other cathepsin B family members with an overall conserved architecture. AcCPB is evolutionarily more close to other parasitic nematode cathepsin B than the ones from hosts, sharing 43-53% similarities to the homologues from other organisms. Real-time quantitative PCR analysis revealed that AcCPB was expressed significantly higher in the fourth-stage larvae (L4) and the fifth-stage larvae (L5) than that in the third-stage larvae (L3) and adult worms (Aw). Unexpectedly, AcCPB was expressed at a higher level in L4 and L5 derived from mice than the larvae at the same stages derived from rats. The protease activity of recombinant AcCPB (rAcCPB) expressed in Escherichia coli showed high thermostability and acidic pH optima. The role in ovalbumin digestion and enzyme activity of rAcCPB could be evidently inhibited by cystatin from A.cantonensis. Furthermore, we found rAcCPB increased the expression levels of CD40, MHC II, and CD80 on LPS-stimulated dendritic cells (DCs). In this study, we provided the first experimental evidence for the expression of cathepsin B in A.cantonensis. Besides its highly specific expression in the stages of L4 and L5 when the worms cause dysfunction of the blood-brain barrier of hosts, AcCPB displayed different expression profiles in non-permissive host- and permissive host-derived larval stages and was involved in the maturation of DCs, suggesting a potential role in the central nervous system invasion and the immunoregulation during parasite-host interactions.


Assuntos
Angiostrongylus cantonensis/enzimologia , Angiostrongylus cantonensis/genética , Catepsina B/genética , Catepsina B/metabolismo , Sequência de Aminoácidos , Animais , Clonagem Molecular , Análise por Conglomerados , Células Dendríticas/imunologia , Estabilidade Enzimática , Escherichia coli/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Filogenia , Ratos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Temperatura
15.
Neuropharmacology ; 189: 108515, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33722649

RESUMO

Patients deprived of cigarettes exhibit increased pain sensitivity during perioperative periods, yet the underlying neuroanatomical and molecular bases of this hypersensitivity are unclear. The present study showed that both the mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were significantly decreased in a rat model of nicotine withdrawal. These rats showed less tryptophan hydroxylase 2 (TPH2) positive neurons and reduced TPH2 expression in the nucleus raphe magnus (NRM), and thus resulted in decreased 5-hydroxytryptamine (5-HT) levels in cerebrospinal fluid. Intrathecal injection of 5-HT or NRM microinjection of TPH-overexpression adeno-associated virus alleviated nicotine withdrawal-induced hyperalgesia, whereas 5-HT receptor pharmacological blockade by methysergide (a 5-HT receptor antagonist) exacerbated hypersensitivity and diminished the difference between the two groups. Together, these data indicate that hyperalgesia after nicotine withdrawal is mediated by declined descending serotonergic pathways in the NRM. This provides a new perspective to improve the postoperative pain management of patients, especially the smokers.


Assuntos
Regulação para Baixo/fisiologia , Hiperalgesia/metabolismo , Nicotina/efeitos adversos , Núcleo Magno da Rafe/metabolismo , Neurônios Serotoninérgicos/metabolismo , Síndrome de Abstinência a Substâncias/metabolismo , Animais , Regulação para Baixo/efeitos dos fármacos , Hiperalgesia/tratamento farmacológico , Injeções Espinhais , Injeções Subcutâneas , Masculino , Nicotina/administração & dosagem , Núcleo Magno da Rafe/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores de Serotonina/metabolismo , Neurônios Serotoninérgicos/efeitos dos fármacos , Serotonina/administração & dosagem , Serotonina/metabolismo , Síndrome de Abstinência a Substâncias/tratamento farmacológico
16.
Math Biosci Eng ; 17(4): 3062-3087, 2020 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-32987517

RESUMO

In this paper we introduce a method of global exponential attractor in the reaction-diffusion epidemic model in spatial heterogeneous environment to study the spread trend and long-term dynamic behavior of the COVID-19 epidemic. First, we prove the existence of the global exponential attractor of general dissipative evolution systems. Then, by using the existence theorem, the global asymptotic stability and the persistence of epidemic are discussed. Finally, combine with the official data of the COVID-19 and the national control strategy, some numerical simulations on the stability and global exponential attractiveness of the COVID-19 epidemic are given. Simulations show that the spread trend of the epidemic is in line with our theoretical results, and the preventive measures taken by the Chinese government are effective.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Epidemias , Modelos Biológicos , Pneumonia Viral/epidemiologia , COVID-19 , China/epidemiologia , Simulação por Computador , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Epidemias/prevenção & controle , Epidemias/estatística & dados numéricos , Humanos , Conceitos Matemáticos , Pandemias/prevenção & controle , Pandemias/estatística & dados numéricos , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Quarentena/estatística & dados numéricos , SARS-CoV-2
17.
Math Biosci Eng ; 16(5): 5897-5922, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31499744

RESUMO

In this paper by adding the factors of disease relapse and vaccination in the space hetero-geneous environment, we establish and discuss a class of reaction-diffusion SVIR model with relapse and a varying external source in spatial heterogeneous environment. By applying a different method than the Lyapunov function, we study the long-term dynamic behavior of this model by means of global exponential attractor theory and gradient flow method. The global asymptotic stability and the persistence of epidemic are proved. To test the validity of our theoretical results, we choose some specific epidemic disease with some more practical and more definitive official data to simulate the global stability and exponential attraction of the model. The simulation results showed that the factors of disease relapse, vaccination and spatial heterogeneity had a great influence on the persists uniformly of the disease.

18.
Ophthalmic Genet ; 38(1): 67-69, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27029465

RESUMO

BACKGROUND: Mitochondrial disease often manifests with ophthalmologic signs and symptoms. Due to the important role of mitochondria in aerobic metabolism, the eyes are among the more preferentially involved organs. The clinical diagnosis of mitochondrial disease can be facilitated by an improved knowledge of the types and magnitude of their various manifestations. The aim of this study was to describe the ophthalmological manifestations of patients with mitochondrial diseases that are currently not well elucidated. METHODS: From a database of patients with verified primary mitochondrial disease (n = 81) who had visited our institution we identified 74 patients who had ophthalmologic examinations. Demographic, clinical, and ophthalmologic data were collected. Institutional review board approval was obtained. RESULTS: A total of 74 patients were identified with Leigh disease, MELAS, MERRF, CPEO, Pearson/Kearns-Sayre syndrome, as well as other mtDNA point mutations, deletions, depletions, and mutations. Overall, 26 of the 74 patients (35%) had one or more ophthalmological abnormalities. Retinal pigmentary changes were present in 12/74 (16%) of patients. Partial or total optic atrophy (OA) was noted in 8/74 (10%) of patients. Decreased extra-ocular movement (EOM) was noted in 6/74 (8%) of patients. Other ophthalmological findings included macular atrophy (2/74), macular dystrophy (1/74), and visual field defects (1/74). CONCLUSIONS: Over one-third of our cohort of patients with mitochondrial disorders had ophthalmological manifestations, some of which affected vision significantly. Eye examinations are critical in patients with mitochondrial disease so that complete assessments of the effects of the underlying mutations are uncovered and the appropriate counseling and care are given.


Assuntos
Oftalmopatias/diagnóstico , Doenças Mitocondriais/diagnóstico , Adulto , DNA Mitocondrial/genética , Oftalmopatias/genética , Feminino , Humanos , Síndrome de Kearns-Sayre/diagnóstico , Síndrome de Kearns-Sayre/genética , Doença de Leigh/diagnóstico , Doença de Leigh/genética , Síndrome MELAS/diagnóstico , Síndrome MELAS/genética , Síndrome MERRF/diagnóstico , Síndrome MERRF/genética , Masculino , Doenças Mitocondriais/genética , Oftalmoplegia Externa Progressiva Crônica/diagnóstico , Oftalmoplegia Externa Progressiva Crônica/genética , Mutação Puntual , Estudos Retrospectivos , Deleção de Sequência/genética
19.
J Biol Dyn ; 11(1): 275-298, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28625104

RESUMO

A drinking model with immigration is constructed. For the model with problem drinking immigration, the model admits only one problem drinking equilibrium. For the model without problem drinking immigration, the model has two equilibria, one is problem drinking-free equilibrium and the other is problem drinking equilibrium. By employing the method of Lyapunov function, stability of all kinds of equilibria is obtained. Numerical simulations are also provided to illustrate our analytical results. Our results show that alcohol immigrants increase the difficulty of the temperance work of the region.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Comportamento , Emigração e Imigração , Modelos Biológicos , Simulação por Computador , Humanos , Análise Numérica Assistida por Computador
20.
Cell Cycle ; 16(1): 82-90, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-27830977

RESUMO

Polyploids are pervasive in plants and have large impacts on crop breeding, but natural polyploids are rare in animals. Mouse diploid embryos can be induced to become tetraploid by blastomere fusion at the 2-cell stage and tetraploid embryos can develop to the blastocyst stage in vitro. However, there is little information regarding mouse octaploid embryonic development and precise mechanisms contributing to octaploid embryonic developmental limitations are unknown. To investigate the genetic and epigenetic mechanisms underlying octaploid embryonic development, we generated mouse octaploid embryos and evaluated the in vitro/in vivo developmental potential. Here we show that octaploid embryos can develop to the blastocyst stage in vitro, but all fetus impaired immediately after implantation. Our results indicate that cell lineage specification of octaploid embryo was disorganized. Furthermore, these octaploid embryos showed increased apoptosis as well as alterations in epigenetic modifications when compared with diploid embryos. Thus, our cumulative data provide cues for why mouse octaploid embryonic development is limited and its failed postimplantation development.


Assuntos
Apoptose/genética , Autofagia/genética , Desenvolvimento Embrionário/genética , Epigênese Genética , Poliploidia , Animais , Biomarcadores/metabolismo , Blastocisto/citologia , Blastocisto/metabolismo , Linhagem da Célula/genética , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Feminino , Camundongos Endogâmicos ICR , Modelos Biológicos
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