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1.
J Med Chem ; 67(11): 9104-9123, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38829030

RESUMO

Amyloid-ß oligomers (AßOs), crucial toxic proteins in early Alzheimer's disease (AD), precede the formation of Aß plaques and cognitive impairment. In this context, we present our iterative process for developing novel near-infrared fluorescent (NIRF) probes specifically targeting AßOs, aimed at early AD diagnosis. An initial screening identified compound 18 as being highly selective for AßOs. Subsequent analysis revealed that compound 20 improved serum stability while retaining affinity for AßOs. The most promising iteration, compound 37, demonstrated exceptional qualities: a high affinity for AßOs, emission in the near-infrared region, and good biocompatibility. Significantly, ex vivo double staining indicated that compound 37 detected AßOs in AD mouse brain and in vivo imaging experiments showed that compound 37 could differentiate between 4-month-old AD mice and age-matched wild-type mice. Therefore, compound 37 has emerged as a valuable NIRF probe for early detection of AD and a useful tool in exploring AD's pathological mechanisms.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Desenho de Fármacos , Diagnóstico Precoce , Corantes Fluorescentes , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/diagnóstico por imagem , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Animais , Peptídeos beta-Amiloides/metabolismo , Camundongos , Humanos , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Camundongos Transgênicos
2.
Cell Rep ; 43(1): 113651, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38175751

RESUMO

Dynamic chromosome remodeling and nuclear compartmentalization take place during mammalian meiotic prophase I. We report here that the crucial roles of male pachynema-specific protein (MAPS) in pachynema progression might be mediated by its liquid-liquid phase separation in vitro and in cellulo. MAPS forms distinguishable liquid phases, and deletion or mutations of its N-terminal amino acids (aa) 2-9 disrupt its secondary structure and charge properties, impeding phase separation. Maps-/- pachytene spermatocytes exhibit defects in nucleus compartmentalization, including defects in forming sex bodies, altered nucleosome composition, and disordered chromatin accessibility. MapsΔ2-9/Δ2-9 male mice expressing MAPS protein lacking aa 2-9 phenocopy Maps-/- mice. Moreover, a frameshift mutation in C3orf62, the human counterpart of Maps, is correlated with nonobstructive azoospermia in a patient exhibiting pachynema arrest in spermatocyte development. Hence, the phase separation property of MAPS seems essential for pachynema progression in mouse and human spermatocytes.


Assuntos
Cromatina , Meiose , Humanos , Masculino , Camundongos , Animais , Cromatina/metabolismo , Estágio Paquíteno , Separação de Fases , Prófase Meiótica I , Espermatócitos/metabolismo , Mamíferos/genética
3.
Asian J Androl ; 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37856231

RESUMO

ABSTRACT: Meiosis is the process of producing haploid gametes through a series of complex chromosomal events and the coordinated action of various proteins. The mitochondrial protease complex (ClpXP), which consists of caseinolytic mitochondrial matrix peptidase X (ClpX) and caseinolytic protease P (ClpP) and mediates the degradation of misfolded, damaged, and oxidized proteins, is essential for maintaining mitochondrial homeostasis. ClpXP has been implicated in meiosis regulation, but its precise role is currently unknown. In this study, we engineered an inducible male germ cell-specific knockout caseinolytic mitochondrial matrix peptidase X (ClpxcKO) mouse model to investigate the function of ClpX in meiosis. We found that disrupting Clpx in male mice induced germ cell apoptosis and led to an absence of sperm in the epididymis. Specifically, it caused asynapsis of homologous chromosomes and impaired meiotic recombination, resulting in meiotic arrest in the zygotene-to-pachytene transition phase. The loss of ClpX compromised the double-strand break (DSB) repair machinery by markedly reducing the recruitment of DNA repair protein RAD51 homolog 1 (RAD51) to DSB sites. This dysfunction may be due to an insufficient supply of energy from the aberrant mitochondria in ClpxcKO spermatocytes, as discerned by electron microscopy. Furthermore, ubiquitination signals on chromosomes and the expression of oxidative phosphorylation subunits were both significantly attenuated in ClpxcKO spermatocytes. Taken together, we propose that ClpX is essential for maintaining mitochondrial protein homeostasis and ensuring homologous chromosome pairing, synapsis, and recombination in spermatocytes during meiotic prophase I.

4.
J Med Chem ; 65(12): 8144-8168, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35679512

RESUMO

Akt has emerged as an exciting target in oncology due to its critical roles in proliferation, survival, metabolism, metastasis, and invasion in tumor cells. Herein, we describe the discovery and optimization of a series of ATP-competitive Akt inhibitors that possess new chemical scaffolds and exhibit potent enzymatic activities and improved in vivo pharmacokinetic profiles. Remarkably, NTQ1062 (compound 22b) exhibited potent antitumor efficacies in vitro and in vivo, which was accomplished through the optimization of the hinge binder region and the linkage. Subsequent studies of NTQ1062 demonstrated that it possesses good oral pharmacokinetic characteristics and dose-dependent pharmacodynamic effects on downstream biomarkers. In addition, NTQ1062 exhibits a robust antitumor efficacy in xenograft models in which the PI3K-Akt-mTOR pathway was activated. Based on its ideal druglike properties, NTQ1062 is currently being evaluated in a phase I clinical trial for the treatment of advanced solid tumors (CTR20211999).


Assuntos
Antineoplásicos , Inibidores de Proteínas Quinases , Proteínas Proto-Oncogênicas c-akt , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
5.
PNAS Nexus ; 1(3): pgac108, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36741430

RESUMO

In-vitro fertilization is an effective treatment for various causes of infertility. However, management of women with poor ovarian response or premature ovarian insufficiency remains challenging because these women have underdeveloped small ovarian follicles that do not respond to hormone treatment. In-vitro activation of small follicles has been developed but its efficiency has much room for improvement. In the current study, we provide several lines of evidence showing that curcumin, an FDA-approved traditional medicine, can specifically promote the development of mouse ovarian follicles from the primary to secondary stage, which greatly potentiates these small follicles for subsequent in-vivo development into antral follicles that can be ovulated. Mechanistically, we show that curcumin promotes the proliferation and differentiation of granulosa cells and the growth of oocytes by activating the phosphatidylinositol 3 kinase (PI3K) signaling pathway. Most importantly, we show that in-vitro treatment of human ovarian tissues with curcumin can promote the in-vivo survival and development of small human ovarian follicles, showing that curcumin can be used as a potential drug to increase the success rate of in-vitro activation of small human follicles. We thus identify curcumin as a novel potential drug for promoting the development of small human ovarian follicles for infertility treatment.

6.
Cells ; 10(6)2021 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-34199299

RESUMO

The mammalian ovary has two main functions-producing mature oocytes for fertilization and secreting hormones for maintaining the ovarian endocrine functions. Both functions are vital for female reproduction. Primordial follicles are composed of flattened pre-granulosa cells and a primary oocyte, and activation of primordial follicles is the first step in follicular development and is the key factor in determining the reproductive capacity of females. The recent identification of the phosphatidylinositol 3 kinase (PI3K)/phosphatase and tensin homolog deleted on chromosome 10 (PTEN) signaling pathway as the key controller for follicular activation has made the study of primordial follicle activation a hot research topic in the field of reproduction. This review systematically summarizes the roles of the PI3K/PTEN signaling pathway in primordial follicle activation and discusses how the pathway interacts with various other molecular networks to control follicular activation. Studies on the activation of primordial follicles have led to the development of methods for the in vitro activation of primordial follicles as a treatment for infertility in women with premature ovarian insufficiency or poor ovarian response, and these are also discussed along with some practical applications of our current knowledge of follicular activation.


Assuntos
Infertilidade Feminina/metabolismo , Folículo Ovariano/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Insuficiência Ovariana Primária/metabolismo , Transdução de Sinais , Animais , Feminino , Humanos
7.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33602822

RESUMO

Meiosis is a specialized cell division that creates haploid germ cells from diploid progenitors. Through differential RNA expression analyses, we previously identified a number of mouse genes that were dramatically elevated in spermatocytes, relative to their very low expression in spermatogonia and somatic organs. Here, we investigated in detail 1700102P08Rik, one of these genes, and independently conclude that it encodes a male germline-specific protein, in agreement with a recent report. We demonstrated that it is essential for pachynema progression in spermatocytes and named it male pachynema-specific (MAPS) protein. Mice lacking Maps (Maps-/- ) suffered from pachytene arrest and spermatocyte death, leading to male infertility, whereas female fertility was not affected. Interestingly, pubertal Maps-/- spermatocytes were arrested at early pachytene stage, accompanied by defects in DNA double-strand break (DSB) repair, crossover formation, and XY body formation. In contrast, adult Maps-/- spermatocytes only exhibited partially defective crossover but nonetheless were delayed or failed in progression from early to mid- and late pachytene stage, resulting in cell death. Furthermore, we report a significant transcriptional dysregulation in autosomes and XY chromosomes in both pubertal and adult Maps-/- pachytene spermatocytes, including failed meiotic sex chromosome inactivation (MSCI). Further experiments revealed that MAPS overexpression in vitro dramatically decreased the ubiquitination levels of cellular proteins. Conversely, in Maps-/- pachytene cells, protein ubiquitination was dramatically increased, likely contributing to the large-scale disruption in gene expression in pachytene cells. Thus, MAPS is a protein essential for pachynema progression in male mice, possibly in mammals in general.


Assuntos
Infertilidade Masculina/patologia , Meiose , Proteínas Nucleares/fisiologia , Estágio Paquíteno , Espermatócitos/patologia , Espermatogênese , Animais , Pareamento Cromossômico , Reparo do DNA , Feminino , Infertilidade Masculina/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Cromossomos Sexuais , Espermatócitos/metabolismo
8.
J Genet Genomics ; 47(8): 451-465, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-33250349

RESUMO

Meiosis is a specialized cell division for producing haploid gametes in sexually reproducing organisms. In this study, we have independently identified a novel meiosis protein male meiosis recombination regulator (MAMERR)/4930432K21Rik and showed that it is indispensable for meiosis prophase I progression in male mice. Using super-resolution structured illumination microscopy, we found that MAMERR functions at the same double-strand breaks as the replication protein A and meiosis-specific with OB domains/spermatogenesis associated 22 complex. We generated a Mamerr-deficient mouse model by deleting exons 3-6 and found that most of Mamerr-/- spermatocytes were arrested at pachynema and failed to progress to diplonema, although they exhibited almost intact synapsis and progression to the pachytene stage along with XY body formation. Further mechanistic studies revealed that the recruitment of DMC1/RAD51 and heat shock factor 2-binding protein in Mamerr-/- spermatocytes was only mildly impaired with a partial reduction in double-strand break repair, whereas a substantial reduction in ubiquitination on the autosomal axes and on the XY body appeared as a major phenotype in Mamerr-/- spermatocytes. We propose that MAMERR may participate in meiotic prophase I progression by regulating the ubiquitination of key meiotic proteins on autosomes and XY chromosomes, and in the absence of MAMERR, the repressed ubiquitination of key meiotic proteins leads to pachytene arrest and cell death.


Assuntos
Proteínas de Ciclo Celular/genética , Cromossomos/genética , Meiose/genética , Prófase Meiótica I/genética , Animais , Pareamento Cromossômico/genética , Quebras de DNA de Cadeia Dupla , Reparo do DNA/genética , Masculino , Camundongos , Recombinação Genética/genética , Espermatócitos/citologia , Espermatogênese/genética
9.
J Phys Chem Lett ; 11(21): 9019-9025, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33040534

RESUMO

Blade-coating is a potential method for preparing all-solution-processed quantum dot light-emitting diodes (QLEDs) because of its high material utilization and large-scale preparation compatibility. However, it is a challenge to prepare uniform-emitting, high-performance QLEDs by blade coating because of film uniformity issues. Here, we report an efficient all-blade-coated QLED through solvent engineering. A binary water/methanol solvent is used to decrease the surface tension, leading to uniform blade-coating poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) films. The binary solvent also enhances hole transport abilities because of phase separations and chain reorientations of PEDOT and PSS chains. The uniformity of a poly(N-vinylcarbazole) (PVK) layer is also improved by using a chlorobenzene/toluene binary solvent to facilitate the spontaneous spreading of the PVK solution on the substrate. This enables the successful preparation of an efficient QLED with a maximum external quantum efficiency of 12.48%, which is about 2.6 times the value of the QLED without solvent engineering.

10.
Sci Adv ; 5(8): eaax1101, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31453335

RESUMO

Meiosis is a specialized type of cell division that creates haploid germ cells and ensures their genetic diversity through homologous recombination. We show that the H3K4me3 reader ZCWPW1 is specifically required for meiosis prophase I progression in male but not in female germ cells in mice. Loss of Zcwpw1 in male mice caused a complete failure of synapsis, resulting in meiotic arrest at the zygotene to pachytene stage, accompanied by incomplete DNA double-strand break repair and lack of crossover formation, leading to male infertility. In oocytes, deletion of Zcwpw1 only somewhat slowed down meiosis prophase I progression; Zcwpw1-/- oocytes were able to complete meiosis, and Zcwpw1-/- female mice had normal fertility until mid-adulthood. We conclude that the H3K4me3 reader ZCWPW1 is indispensable for meiosis synapsis in males but is dispensable for females. Our results suggest that ZCWPW1 may represent a previously unknown, sex-dependent epigenetic regulator of germ cell meiosis in mammals.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Reparo do DNA por Junção de Extremidades/genética , Código das Histonas/genética , Prófase Meiótica I/genética , Oócitos/citologia , Espermatozoides/citologia , Animais , Proteínas de Ciclo Celular/genética , Quebras de DNA de Cadeia Dupla , Feminino , Histonas/genética , Infertilidade Masculina/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores Sexuais
11.
J Steroid Biochem Mol Biol ; 191: 105379, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31078694

RESUMO

Estrogens play fundamental roles in regulating reproductive activities and they act through estrogen receptors (ESRs) in all vertebrates. To date, distinct roles of estrogen receptors have been characterized only in human and model organisms, including mouse, rat, zebrafish and medaka. Physiological role of estrogen/receptor signaling in reproduction remains poorly defined in non-model organisms. In the present study, we successfully generated esr1, esr2a and esr2b mutant lines in tilapia by CRISPR/Cas9 and examined their phenotypes. Surprisingly, the esr1 mutants showed no phenotypes of reproductive development and function in both females and males. The esr2a mutant females showed significantly delayed ovarian development and follicle growth at 90 and 180 dah, and the development caught up later at 360 dah. The esr2a mutant males showed no phenotypes at 90 dah, and displayed smaller gonads and efferent ducts, less spermatogonia and more abnormal sperms at 180 dah. In contrast, the esr2b mutants displayed abnormal development of ovarian ducts and efferent ducts which failed to connect to the genital orifice, and which in turn, resulted in infertility in female and male, respectively, although they produced gametes in their gonads. Taken together, our study provides evidence for differential functions of esr1, esr2a and esr2b in fish reproduction.


Assuntos
Ciclídeos/genética , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Proteínas de Peixes/genética , Animais , Sistemas CRISPR-Cas , Linhagem Celular , Ciclídeos/fisiologia , Feminino , Masculino , Mutação , Reprodução
12.
Nanoscale Res Lett ; 13(1): 310, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30288619

RESUMO

At present, numerous functional layers are introduced to improve the carrier injection and balance the carrier transport in organic light-emitting devices (OLEDs). Although it may be a good way to enhance the efficiency of devices, the introduction of functional layers would also result in extra process and long manufacture period. Actually, with the enrichment of material system, many appropriate materials could be chosen to share two or even more functions in OLEDs. Here, via impedance spectroscopy and transient electroluminescence analysis, di-[4-(N,N-ditolyl-amino)-phenyl] cyclohexane (TAPC) and 4,7-diphenyl-1,10-phenanthroline (Bphen) are demonstrated to serve as carrier injection and transport layers simultaneously. As a result, efficient trilayer OLEDs are achieved with comparable performances to conventional multilayer devices. Further studies have also been carried out to analyze the recombination and quenching mechanisms in devices. TAPC can block electrons effectively, while Bphen avoids the accumulation of holes. It makes carriers in emitting layer become more balanced, resulting in the reduction of efficiency roll-off.

13.
Eur J Med Chem ; 128: 180-191, 2017 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-28182990

RESUMO

A novel series of non-peptide proteasome inhibitors bearing the 1, 4-naphthoquinone scaffold and boronic acid warhead was developed. In the biological evaluation on the chymotrypsin-like activity of human 20S proteasome, five compounds showed IC50 values in the nanomolar range. Docking experiments into the yeast 20S proteasome rationalized their biological activities and allowed further optimization of this interesting class of inhibitors. Within the cellular proliferation inhibition assay and western blot analysis, compound 3e demonstrated excellent anti-proliferative activity against solid tumor cells and clear accumulation of ubiquitinated cellular proteins. Furthermore, in the microsomal stability assay compound 3e demonstrated much improved metabolic stability compared to bortezomib, emerging as a promising lead compound for further design of non-peptide proteasome inhibitors.


Assuntos
Antineoplásicos/farmacologia , Ácidos Borônicos/química , Proliferação de Células/efeitos dos fármacos , Dipeptídeos/farmacologia , Desenho de Fármacos , Naftoquinonas/farmacologia , Complexo de Endopeptidases do Proteassoma/química , Inibidores de Proteassoma/farmacologia , Animais , Antineoplásicos/química , Western Blotting , Bortezomib/farmacologia , Células Cultivadas , Dipeptídeos/química , Humanos , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Naftoquinonas/química , Inibidores de Proteassoma/química , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
14.
Anal Biochem ; 523: 17-23, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28137603

RESUMO

In this paper, we developed a fluorescent aptasensor for 17ß-estradiol (E2) determination in aqueous solution using label-free E2-specific aptamer, gold nanoparticles (AuNPs) and Rhodamine B (RhoB) as sensing probe, fluorescent quencher and fluorescent indicator respectively. In the absence of E2, AuNPs were wrapped by E2 aptamer and maintained dispersed in NaCl solution basically. These dispersed AuNPs could effectively impair the originally high fluorescence of RhoB. Contrarily, in the presence of E2, E2 aptamer could specifically combine with E2 to form E2-aptamer complex, so the AuNPs were released by E2 aptamer and aggregated under the influence of NaCl. The aggregated AuNPs have a weak influence on RhoB fluorescence. Therefore, the E2 concentration can be determined by the change of fluorescence intensity of RhoB. This fluorescent assay has a detection limit as low as 0.48 nM, a linear range from 0.48 to 200 nM, and high selectivity over other disrupting chemicals. It was applied to determine E2 in water samples with recoveries in the range of 94.3-111.7%. The fluorescent aptasensor holds great potential for E2 detection in environmental water samples.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Estradiol/análise , Fluorescência , Ouro/química , Nanopartículas Metálicas/química , Rodaminas/química , Corantes Fluorescentes/química , Humanos , Limite de Detecção
15.
Huan Jing Ke Xue ; 38(2): 783-791, 2017 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964538

RESUMO

The utilization of straw resources is of great significance to agricultural environmental protection and sustainable agricultural development. Based on the isolated 15 high-efficient cellulose degrading bacteria in the laboratory, the composite inoculants (JFB-1) which can effectively degrade crop straw were screened, and the effects of straw composts with the composite inoculants on soil carbon and nitrogen contents and enzyme activity were studied. The results showed that the composite inoculants could accelerate straw decomposition for 1-2 d during single fermentation period, and the organic matter contents in straw composts reached 403.5-515.1 g·kg-1, while the ratio of carbon and nitrogen decreased from 10.53 to 15.30. The pot experiments found that the application effects of rice straw composts were generally better than those of corresponding asparagus straw composts. Compared with the control compost of rice straw, when the application amount of rice straw compost using the composite inoculants was 150 g·kg-1, the contents of soil organic matter and total nitrogen increased by 33.5% and 7.3%, and soil urease and cellulase activities increased by 16.7% and 30.8%, respectively. Compared with no fertilization treatment, the application of straw composts could improve soil microbial community structure, and increase microbial diversity indices. When the application amount of rice straw compost using the composite inoculants was 100 g·kg-1, the biomass of common Chinese cabbage cultivated for 30 d increased by 46.4% compared to the control compost of rice straw. These results indicated that the composite inoculants have great application potential in straw composts.


Assuntos
Carbono/análise , Compostagem , Enzimas/análise , Nitrogênio/análise , Microbiologia do Solo , Solo/química , Agricultura , Oryza
16.
Chem Sci ; 8(11): 7710-7717, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29568434

RESUMO

Amyloid peptides and proteins are associated with the pathologies of numerous diseases. In the progression of a disease, amyloids exist in soluble and insoluble forms, which are the dominant species at different stages of the disease and they have different degrees of toxicity. However, differentiating between the soluble and insoluble forms is very challenging with small molecule probes due to multiple obstacles that need to be overcome. Inspired by the recognition principle of antibodies for sAß, we hypothesized that the accessibility/tightness of soluble and insoluble amyloids could be utilized to design imaging probes to recognize different amyloid forms and the stereo-hindrance tuning strategy could be used to design imaging probes for selectively detecting the soluble amyloid beta (sAß) species in Alzheimer's disease (AD). Herein, we demonstrated that tuning the stereo-hindrance of the phenoxy-alkyl chains at the 4-position of a curcumin scaffold could lead to certain selectivity for sAß over insoluble Aßs (insAß). Among the designed compounds, CRANAD-102 showed a 68-fold higher affinity for sAß than for insAß (7.5 ± 10 nM vs. 505.9 ± 275.9 nM). Moreover, our imaging data indicated that CRANAD-102 was indeed capable of detecting sAß in vivo using 4 month old APP/PS1 mice, in which sAß is the predominant species in the brain. In addition, we also demonstrated that CRANAD-102 could be used to monitor the increase in sAß loading from the ages of 4 months old to 12 months old. We believe that CRANAD-102 can be a useful probe for selectively detecting sAß species in AD and that our probe designing strategy can be applied to other amyloids and will have tremendous impact on AD drug development and other amyloid research.

17.
J Endocrinol ; 228(3): 205-18, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26759274

RESUMO

Estrogen, which is synthesized earlier in females than androgen in males, is critical for sex determination in non-mammalian vertebrates. However, it remains unknown that what would happen to the gonadal phenotype if estrogen and androgen were administrated simultaneously. In this study, XY and XX tilapia fry were treated with the same dose of 17α-methyltestosterone (MT) and 17ß-estradiol (E2) alone and in combination from 0 to 30 days after hatching. Treatment of XY fish with E2 resulted in male to female sex reversal, while treatment of XX fish with MT resulted in female to male sex reversal. In contrast, simultaneous treatment of XX and XY fish with MT and E2 resulted in female, but with cyp11b2 and cyp19a1a co-expressed in the ovary. Serum 11-ketotestosteron level of the MT and E2 simultaneously treated XX and XY female was similar to that of the XY control, while serum E2 level of these two groups was similar to that of the XX control. Transcriptomic cluster analysis revealed that the MT and E2 treated XX and XY gonads clustered into the same branch with the XX control. However a small fraction of genes, which showed disordered expression, may be associated with stress response. These results demonstrated that estrogen could maintain the female phenotype of XX fish and feminize XY fish even in the presence of androgen. Simultaneous treatment with estrogen and androgen up-regulated the endogenous estrogen and androgen synthesis, and resulted in disordered gene expression and endocrine disruption in tilapia.


Assuntos
Disruptores Endócrinos , Estradiol/administração & dosagem , Feminização/veterinária , Doenças dos Peixes/induzido quimicamente , Metiltestosterona/administração & dosagem , Tilápia , Animais , Estradiol/sangue , Feminino , Feminização/induzido quimicamente , Expressão Gênica/efeitos dos fármacos , Masculino , Fenótipo , Fatores Sexuais , Testosterona/análogos & derivados , Testosterona/sangue
18.
Yao Xue Xue Bao ; 50(5): 528-34, 2015 May.
Artigo em Chinês | MEDLINE | ID: mdl-26234131

RESUMO

Alzheimer's disease (AD) is the most common cause of cognitive impairment in older people. With the aging of society is more and more serious, AD caused great burden to patients and society. A ß is a classical biomarker of AD, which has been widely used in clinical diagnosis of AD patients. Compared with positron emission tomography (PET) and single photon emission computed tomography (SPECT), near infrared fluorescence imaging has many advantages including highly sensitive, non-invasive, safety and inexpensive. Therefore, many research groups have focused on developing the molecular probes of near-infrared fluorescence (NIRF) imaging. In this article, we will review the progress of the probes of NIRF.


Assuntos
Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/análise , Corantes Fluorescentes , Fluorescência , Humanos , Sondas Moleculares , Tomografia por Emissão de Pósitrons , Espectroscopia de Luz Próxima ao Infravermelho , Tomografia Computadorizada de Emissão de Fóton Único
19.
Environ Sci Pollut Res Int ; 22(24): 19860-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26286803

RESUMO

Microorganism or chelate-assisted phytoextraction is an effective remediation tool for heavy metal polluted soil, but investigations into its impact on soil microbial activity are rarely reported. Consequently, cadmium (Cd)- and lead (Pb)-resistant fungi and citric acid (CA) were introduced to enhance phytoextraction by Solanum nigrum L. under varied Cd and Pb pollution levels in a greenhouse pot experiment. We then determined accumulation of Cd and Pb in S. nigrum and the soil enzyme activities of dehydrogenase, phosphatase, urease, catalase, sucrase, and amylase. Detrended canonical correspondence analysis (DCCA) was applied to assess the interactions between remediation strategies and soil enzyme activities. Results indicated that the addition of fungi, CA, or their combination enhanced the root biomass of S. nigrum, especially at the high-pollution level. The combined treatment of CA and fungi enhanced accumulation of Cd about 22-47 % and of Pb about 13-105 % in S. nigrum compared with the phytoextraction alone. However, S. nigrum was not shown to be a hyperaccumulator for Pb. Most enzyme activities were enhanced after remediation. The DCCA ordination graph showed increasing enzyme activity improvement by remediation in the order of phosphatase, amylase, catalase, dehydrogenase, and urease. Responses of soil enzyme activities were similar for both the addition of fungi and that of CA. In summary, results suggest that fungi and CA-assisted phytoextraction is a promising approach to restoring heavy metal polluted soil.


Assuntos
Cádmio/isolamento & purificação , Ácido Cítrico/farmacologia , Enzimas/metabolismo , Fungos/fisiologia , Chumbo/isolamento & purificação , Microbiologia do Solo , Solanum nigrum/metabolismo , Biodegradação Ambiental/efeitos dos fármacos , Biomassa , Cádmio/metabolismo , Chumbo/metabolismo , Poluentes do Solo/isolamento & purificação , Poluentes do Solo/metabolismo , Solanum nigrum/efeitos dos fármacos , Solanum nigrum/microbiologia
20.
Appl Biochem Biotechnol ; 176(2): 547-62, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25820450

RESUMO

Streptomyces griseorubens JSD-1 is a novel actinomycete that could grow efficiently upon lignin, and the ligninolytic genes active in this biotransformation were expected to be crucial. To investigate the molecular mechanism of utilizing lignin, genome sequencing was carried out to obtain its draft genome, which was deposited at GenBank under the accession No. JJMG00000000. Multiple copper oxidase (MCO) was obtained, which proved to be an extracellular enzyme and have relative high expression with the stimulation of ligninolytic materials. Judging from its putative 3D structure, the N-terminal of MCO was bared, which was fit for the linkage of poly-HIS10 tag. As a result, heterogeneous expression conditions of recombinant laccase was achieved with TransB(DE3) grown in a modified terrific broth (TB) medium with an extra addition of 0.5% glucose at 30 °C until optical density at 600 nm (OD600) reached 0.8 when expression was induced by 25 µM isopropyl ß-D-1-thiogalactopyranoside (IPTG) and also 100 µM copper sulphate as supplement. Finally, it exhibited special characters of thermal robustness, alkaline activity profiles, high resistance to metallic ions and chemical inhibitors as well as dye decolourization. In summary, our findings illustrated the genetic basic of utilizing lignin in this isolate. Additionally, a novel laccase expected to be potential in agricultural and industrial application was expressed and characterized as well.


Assuntos
Proteínas de Bactérias , Expressão Gênica , Lacase , Streptomyces/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Estabilidade Enzimática , Lacase/biossíntese , Lacase/química , Lacase/genética , Lacase/isolamento & purificação , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Streptomyces/enzimologia
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