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1.
Nanoscale ; 12(3): 1448-1454, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31829376

RESUMO

Intercalation has proven to be a powerful strategy for physical and chemical property modulation in two dimensional (2D) van der Waals (vdW) materials. Traditional gaseous and chemical intercalation methods offer the ability for mass production, and the electrochemical method provides reversible fine tuning for in situ material investigation. Spatial control, or even direct patterning, of ions is widely required for practical device fabrication and integration; yet it is not realized. Here we demonstrate a self-driven ion (Co2+, Sn4+, and Cu2+) intercalation approach with patterning ability on vdW α-MoO3. It is proved that the self-driven intercalation was enabled by the formation of a local galvanic cell and could be controlled by the metal electrode potential and the solution concentration. The universality of self-intercalation was confirmed in various types of 2D materials (MoS2, WS2, MoSe2, WSe2 and graphene). Furthermore, the feasibility of building heterostructures by multiple species (Sn & Co) intercalation in a single nanosheet was demonstrated for broadband photodetection. The enhancement of conductivity and photoresponse was found to be due to the synergistic effect of lattice distortion from Sn intercalation and the d orbital from the Co atom. This approach offers a feasible way for direct nano-fabrication in 2D vdW material and functional device integration.

2.
J Photochem Photobiol B ; 198: 111579, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31401316

RESUMO

The sol-gel/ultrasonically rout produced the novel MnS2-SiO2 nano-hetero-photocatalysts with the various ratio of MnS2. Prepared nano-catalyst were investigated in the photo-degradation of methylene blue under UV light illumination. Structural and optical attributes of as-prepared nano-catalysts were evaluated by X-ray diffraction and photoelectron spectroscopy. The morphological were studied by scanning electron microscopy-EDS, and dynamic light scattering. The diffuse reflectance spectroscopy was applied to examine the band gap energy. The Eg values of SiO2, MnS2-SiO2-0, MnS2-SiO2-1, and MnS2-SiO2-2 nanocomposites are 6.51, 3.85, 3.17, and 2.67 eV, respectively. The particle size of the SiO2 and MnS2-SiO2-1 nanocomposites were 100.0, and 65.0 nm, respectively. The crystallite size values of MnS2-SiO2-1 were 52.21 nm, and 2.9 eV, respectively. MnS2-SiO2 nano-photocatalyst was recognized as the optimum sample by degrading 96.1% of methylene blue from water. Moreover, the influence of pH of the solution, and contact time as decisive factors on the photo-degradation activity were investigated in this project. The optimum data for pH and time were found 9 and 60 min, respectively. The photo-degradation capacity of MnS2-SiO2-2 is improved (96.1%) due to the low band gap was found from UV-vis DRS. The antimicrobial data of MnS2-SiO2 were studied and demonstrated that the MnS2-SiO2 has fungicidal and bactericidal attributes.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Compostos de Manganês/química , Nanocompostos/química , Óxidos/química , Dióxido de Silício/química , Raios Ultravioleta , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Antioxidantes/síntese química , Catálise , Escherichia coli/efeitos dos fármacos , Fungos/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Azul de Metileno/química , Tamanho da Partícula , Streptococcus pyogenes/efeitos dos fármacos
3.
Gene ; 719: 144074, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31446094

RESUMO

Kinesin-14 motor es-kifc1 is highly expressed in the male reproductive system of the Chinese mitten crab Eriocheir sinensis (E. sinensis). In addition to acrosomal formation, es-KIFC1 also tightly surrounds the nucleus and its specific mechanism remains unknown. During spermatogenesis, sperm nucleus dents into a cup-shaped structure with several radial arms and completed the nuclear decondensation. In this study, the spatial expression pattern of es-KIFC1 indicates a potential function in nuclear formation with the nuclear localization sequence (NLS) on N-terminal domain which is crucial for the translocation of es-KIFC1 into the nucleus. The Motor domain is associated with microtubule modulation and the Golgi vesicles positioning. Furthermore, the expression level of es-KIFC1 is not only related to the seasonal variation of crustacean development, but also associates with mature sperm storage. The double strand RNA (dsRNA) mediated RNA interference manifests that the cup-shaped sperm nucleus is remarkably malformed and even separates the chromatin throughout the nuclei at the last stage of spermiogenesis. Besides, the sperm nucleus almost disperses its structure and separates the chromatin into several segments throughout the nucleus showing an asymmetrical performance without cytoskeleton. In summary, these results indicate the importance of es-KIFC1 in microtubule positioning and the maintenance of the mature sperm nuclei.


Assuntos
Proteínas de Artrópodes/genética , Braquiúros/fisiologia , Núcleo Celular/metabolismo , Cinesina/genética , Espermatogênese/genética , Animais , Proteínas de Artrópodes/metabolismo , Núcleo Celular/ultraestrutura , Citoesqueleto/metabolismo , Cinesina/metabolismo , Masculino , Microtúbulos/metabolismo , Transporte Proteico , RNA de Cadeia Dupla/genética , Espermatozoides/ultraestrutura
4.
Cell Death Dis ; 10(8): 541, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31316051

RESUMO

The functions of Sertoli cells in spermatogenesis have attracted much more attention recently. Normal spermatogenesis depends on Sertoli cells, mainly due to their influence on nutrient supply, maintenance of cell junctions, and support for germ cells' mitosis and meiosis. Accumulating evidence in the past decade has highlighted the dominant functions of the MAPK, AMPK, and TGF-ß/Smad signaling pathways during spermatogenesis. Among these pathways, the MAPK signaling pathway regulates dynamics of tight junctions and adherens junctions, proliferation and meiosis of germ cells, proliferation and lactate production of Sertoli cells; the AMPK and the TGF-ß/Smad signaling pathways both affect dynamics of tight junctions and adherens junctions, as well as the proliferation of Sertoli cells. The AMPK signaling pathway also regulates lactate supply. These signaling pathways combine to form a complex regulatory network for spermatogenesis. In testicular tumors or infertile patients, the activities of these signaling pathways in Sertoli cells are abnormal. Clarifying the mechanisms of signaling pathways in Sertoli cells on spermatogenesis provides new insights into the physiological functions of Sertoli cells in male reproduction, and also serves as a pre-requisite to identify potential therapeutic targets in abnormal spermatogenesis including testicular tumor and male infertility.

5.
Nanomaterials (Basel) ; 9(6)2019 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-31159474

RESUMO

The concrete relationship between the process parameters and nanoproduct properties is an important challenge for applying nanotechnology to produce functional nanomaterials. In this study, the relationships between series of process parameters and the medicated nanofibers' diameter were investigated. With an electrospinnable solution of hydroxypropyl methylcellulose (HPMC) and ketoprofen as the core fluid, four kinds of nanofibers were prepared with ethanol as a sheath fluid and under the variable applied voltages. Based on these nanofibers, a series of relationships between the process parameters and the nanofibers' diameters (D) were disclosed, such as with the height of the Taylor cone (H, D = 125 + 363H), with the angle of the Taylor cone (ɑ, D = 1576 - 19ɑ), with the length of the straight fluid jet (L, D = 285 + 209L), and with the spreading angle of the instable region (θ, D = 2342 - 43θ). In vitro dissolution tests verified that the smaller the diameters, the faster ketoprofen (KET) was released from the HPMC nanofibers. These concrete process-property relationships should provide a way to achieve new knowledge about the electrostatic energy-fluid interactions, and to meanwhile improve researchers' capability to optimize the coaxial process conditions to achieve the desired nanoproducts.

6.
Gene ; 706: 201-210, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31085275

RESUMO

The functional sperm is the key factor for species continuation. The process spermatogenesis, to produce mature sperm is quite complex. It begins with the proliferation and differentiation of spermatogonia, which develop from primary spermatocytes to secondary spermatocytes and round spermatids, which eventually develop into fertile mature sperm. Spermiogenesis is the latest stage of spermatogenesis, where the round spermatids undergo a series of dramatic morphological changes and extreme condensation of chromatin to construct mature sperm with species-specific shape. During spermiogenesis, chromatin remodeling is a unique progress. It leads the nucleosome from a histone-based structure to a mostly protamine-based configuration. The main events of chromatin remodeling are the replacement of histone by histone variants, hyperacetylation, transient DNA strand breaks and repair, variants by transition proteins and finally by protamines. In this review, we synthesize and summarize the current knowledge on the progress of chromatin remodeling during spermiogenesis. We straighten out the chronological order of chromatin remodeling and illustrate the possible regulation mechanisms of each step.


Assuntos
Montagem e Desmontagem da Cromatina/fisiologia , Cromatina/fisiologia , Espermatogênese/fisiologia , Animais , Cromatina/genética , Montagem e Desmontagem da Cromatina/genética , DNA/metabolismo , Histonas/metabolismo , Humanos , Masculino , Maturação do Esperma/genética , Espermátides/metabolismo , Espermatócitos/metabolismo , Espermatogênese/genética , Espermatozoides/metabolismo
7.
Cell Death Dis ; 10(6): 402, 2019 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-31127080

RESUMO

The nuclear localization signal (NLS) in kinesin-14 KIFC1 is associated with nuclear importins and Ran gradient, but detailed mechanism remains unknown. In this study, we found that KIFC1 proteins have specific transport characteristics during cell cycle. In the absence of KIFC1, cell cycle kinetics decrease significantly with a prolonged S phase. After KIFC1 overexpression, the duration of S phase becomes shorten. KIFC1 may transport the recombinant/replicate-related proteins into the nucleus, meanwhile avoiding excessive KIFC1 in the cytoplasm, which results in aberrant microtubule bundling. Interestingly, the deletion of kifc1 in human cells results in a higher ratio of aberrant nuclear membrane, and the degradation of lamin B and lamin A/C. We also found that kifc1 deletion leads to defects in metaphase mitotic spindle assembly, and then results in chromosome structural abnormality. The kifc1-/- cells finally form micronuclei in daughter cells, and results in aneuploidy and chromosome loss in cell cycle. In this study, we demonstrate that kinesin-14 KIFC1 proteins involve in regulating DNA synthesis in S phase, and chromatin maintenance in mitosis, and maintain cell growth in a nuclear transport-independent way.

8.
Nat Commun ; 10(1): 598, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30723204

RESUMO

Epitaxial growth of atomically thin two-dimensional crystals such as transition metal dichalcogenides remains challenging, especially for producing large-size transition metal dichalcogenides bilayer crystals featuring high density of states, carrier mobility and stability at room temperature. Here we achieve in epitaxial growth of the second monolayer from the first monolayer by reverse-flow chemical vapor epitaxy and produce high-quality, large-size transition metal dichalcogenides bilayer crystals with high yield, control, and reliability. Customized temperature profiles and reverse gas flow help activate the first layer without introducing new nucleation centers leading to near-defect-free epitaxial growth of the second layer from the existing nucleation centers. A series of bilayer crystals including MoS2 and WS2, ternary Mo1-xWxS2 and quaternary Mo1-xWxS2(1-y)Se2y are synthesized with variable structural configurations and tunable electronic and optical properties. The robust, potentially universal approach for the synthesis of large-size transition metal dichalcogenides bilayer single crystals is highly-promising for fundamental studies and technological applications.

9.
Gene ; 684: 1-9, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30342167

RESUMO

Kinesins are essential for the transport and positioning of several biomolecules through moving along the microtubule in eukaryotic cells. Up to now, there are 14 kinesin family proteins known. The MAPK pathway which is composed of multiple proteins constituting a complex cascade also plays important roles in cell proliferation, differentiation and apoptosis in eukaryotic cells. MAPK pathway includes three main kinases: MAPK Kinase Kinase, MAPK Kinase and mitogen-activated protein kinase that activate and phosphorylate downstream step by step in which abundant proteins scaffold together in complex ways. To accomplish the transmission of a variety of signals, numbers of kinesins are closely associated with the MAPK cascade such as Kinesin-1, Kinesin-3, Kinesin-5, Kinesin-8, Kinesin-11 and Kinesin-13 families in mammals and two kinds of kinesin-like proteins in plants. Studies have indicated that Kinesin-1 light chain KLC1, Kinesin-1 heavy chain KIF5B and Kinesin-11 family motor KIF26B interact with extracellular signal-regulated kinase ERK closely to regulate neuronal differentiation and mediate the chemosensitivity of osteosarcoma cells to drugs, Kinesin-3 family motor KIF13B and Kinesin-5 family motor Eg5 perform functions in regulating p38 to regulate the myelination of nervous system and facilitate the spindle elongation and tension, Kinesin-8 family motor MS-KIF18A and three isoforms of kinesin-13 can also connect and interact with MAPK pathway to transport estrogen receptor to the nucleus and control cell migration. In plant cells, NPK1-activating kinesin-like protein 1 NACK and AtNACK1 (HIK) kinesin-like protein HINKEL are two members of the plant-specific kinesin-7. They function as Ras at the upstream of MAPK pathway to regulate cytokinesis. This review summarizes the novel roles of kinesins in MAPK cascade and tries to discuss the mechanism of the interaction between them using mammalian and plant cells as models.


Assuntos
Cinesina/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Animais , Citocinese/fisiologia , Humanos , Cinesina/fisiologia , Proteínas Associadas aos Microtúbulos , Microtúbulos/metabolismo , Fosforilação , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Transporte Proteico
10.
Aging (Albany NY) ; 11(24): 12773-12792, 2019 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-31895691

RESUMO

In order to explore the dynamic mechanisms during spermatogenesis of the penaeid prawns, the full length of kifc1 was cloned from testis cDNA of Penaeus japonicus through RACE. Both semi-quantitative RT-PCR and Western blot results indicated that KIFC1 was extensive expressed in different tissue of P. japonicus. Compared with other tissue, the highest expression of KIFC1 occurred in the testis. According to the immunofluorescence results, the KIFC1 protein was detected at each stage of whole process of spermatogenesis. In the spermatogonial phase, KIFC1 mainly dispersed in cytoplasm and co-localized with microtubules, while abundant KIFC1 signal was detected in the nucleus of spermatocytes. At the early stage of spermatids, KIFC1 was transported from the nucleus into the cytoplasm, and it assisted microtubule assembly onto one side of the nucleus. Finally, in mature sperm, it was weakly expressed in the acrosome. This implies that KIFC1 may participate in the mitosis of spermatogonia, meiosis of spermatocyte, and acrosome formation during spermiogenesis; it may also play functions in acrosome maintaining in mature sperm. In addition, the results of KIFC1 knockdown by dsRNA injection in vivo reveal that decreased KIFC1 expression may induce aberrant microtubule assembly, and it leads to spermatogonia and spermatocyte apoptosis.

11.
Nanomedicine (Lond) ; 13(22): 2939-2955, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30457034

RESUMO

With a special size and structure, nanoparticles (NPs) have excellent application prospects in various fields and are widely used in the biomedicine, cosmetics and chemical industries nowadays. However, there have been some reports on the biosafety of this new type of material, pointing out its cytotoxicity in inducing apoptosis. With different physicochemical properties in size, shape, surface charge, and ligand, NPs exhibit different biocompatibilities when interacting with different cells. Therefore, a comprehensive and deep study into the proapoptotic mechanism of NPs is necessary. In the present review, we summarize the NP-triggered apoptotic signal pathways in detail and highlight some important functional molecules involved. We hope our findings and perspectives provide a new direction for the sound development of nanotechnology in the future.


Assuntos
Apoptose/efeitos dos fármacos , Nanopartículas/toxicidade , Materiais Biocompatíveis/toxicidade , Transporte Biológico , Linhagem Celular , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/fisiologia , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Propriedades de Superfície
12.
Gene ; 678: 90-99, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30081192

RESUMO

Human KIF4 is a member of Kinesin-4 kinesin family. The highly conserved structure contains an N-terminal motor region, coiled-coil region and C-terminal loading region. KIF4 plays important roles in DNA repair and DNA replication, which maintains genetic stability. KIF4 is also essential for regulation of mitosis and meiosis. KIF4 cooperates with condensin I and TopoIIα to help with chromosomal condensation, and binds to a plethora of cell-cycle proteins to regulate spindle organization and cytokinesis. Additionally, KIF4 plays roles in germ plasm aggregation and radial order in germ cells. In neuronal cells, KIF4 promotes proper axon growth by transporting substrates P0 and L1 to their proper location. Interestingly, KIF4 is abnormally expressed in a variety of cancers, where KIF4 is often up-regulated but can also be down-regulated in some cancers. This suggests distinctive regulatory mechanisms for different cancers. Recent studies support important roles for KIF4 in cancers such as the promotion of drug resistance or inhibition of apoptosis. Previous studies showed that by inhibiting or enhancing the expression of KIF4, the proliferation of cancer cells can be significantly reduced. Therefore KIF4 has potential as a therapeutic target for cancer therapy. Moreover, the misregulation of KIF4 is related to viral infection and neural system diseases like Alzheimer. We believe better understanding of this protein will help us develop better therapies for the diseases mentioned above. Here, we summarize KIF4 functions in normal cells and in various cancers, and provide an overview on the association between KIF4 disorders and disease progression.


Assuntos
Cromatina/metabolismo , Citoplasma/metabolismo , Cinesina/metabolismo , Neoplasias/metabolismo , Neurônios/metabolismo , Reparo do DNA , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Humanos , Cinesina/química , Cinesina/genética , Meiose , Mitose , Neoplasias/genética , Conformação Proteica
13.
Nanotechnology ; 29(45): 455707, 2018 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-30160236

RESUMO

Heterostructures of two-dimensional (2D) transition metal dichalcogenides (TMDs) offer attractive prospects for practical applications by combining unique physical properties that are distinct from those of traditional structures. In this paper, we demonstrate a three-stage chemical vapor deposition method for the growth of bilayer MoS2-WS2/WS2 heterostructures with the bottom layers being the lateral MoS2-center/WS2-edge monolayer heterostructures and the top layers being the WS2 monolayers. The alternative growth of lateral and vertical heterostructures can be realized by adjusting both the temperature and the carrier gas flow direction. The combined effect of both reverse gas flow and higher growing temperature can promote the epitaxial growth of second layer on the activated nucleation centers of the first monolayer heterostructures. By using customized temperature profiles, single heterostructures including monolayer lateral MoS2-WS2 heterostructures and bilayer lateral WS2(2L)-MoS2(2L) heterostructures could also be obtained. Atomic force microscopy, photoluminescence and Raman mapping studies clearly reveal that these different heterostructure samples are highly uniform. These results thus provide a promising and efficient method for the synthesis of complex heterostructures based on different TMDs materials, which would greatly expand the heterostructure family and broaden their applications.

14.
Aging (Albany NY) ; 10(5): 1146-1165, 2018 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-29851651

RESUMO

Functions of Caspases remain obscure in Crustacea. We studied the existence and participations of apoptosis-related factors in Eriocheir sinensis testis. Three Es-Caspases (Es-Caspase 3/ 7/ 8) in E. sinensis were cloned and characterized. We observed that three es-caspases mRNA had specific expression patterns during spermiogenesis, with weak signal around the nucleus and invaginated acrosomal vesicle in early-stage spermatids, became stronger in middle-stage, finally focused on the acrosomal tube and nucleus in mature sperm. We then investigated the immunostaining intensity and positional alterations of Es-Caspase 3, Es-Caspase 8 and p53 during spermatogenesis, which were correlated with the differential tendencies of cells to undergo apoptosis and specific organelles shaping processes. After apoptotic induction by Cadmium, Es-Caspase 8 increased gradually, while Es-Caspase 3 increased firstly and then decreased, Es-p53 initially decreased and then increased. These results implies that Es-Caspase 3/ Es-Caspase 8/ p53 may play roles in Cadmium-induced apoptosis during spermatogenesis, and Caspase 8-Caspase 3-p53 pathway may interact with extrinsic or intrinsic pathways to regulate the destiny of sperm cells. Our study revealed the indispensable roles of Caspases during spermatogenesis and the possible molecular interactions in response to the Cadmium-induced apoptosis in E. sinensis, which filled the gap of apoptotic mechanisms of crustacean.


Assuntos
Apoptose/efeitos dos fármacos , Cádmio/toxicidade , Caspases/metabolismo , Espermatogênese/efeitos dos fármacos , Espermatogênese/fisiologia , Animais , Braquiúros , Masculino
15.
Oncol Lett ; 16(1): 491-496, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29928437

RESUMO

Endometriosis is a complex and heterogeneous pre-malignant inflammatory disease harboring multiple gene mutations. Previous studies have suggested that caspase recruitment domain family member (CARD)10 and CARD11 mutations may exist in endometriosis. In the present study, a collection of endometriotic lesions and paired peripheral blood from 101 patients with ovarian endometriosis were obtained, and the entire coding sequences of the CARD10 and CARD11 genes were sequenced. Evolutionary conservation analysis and online prediction programs were applied to analyze the disease-causing potential of the identified mutations. A total of 4 novel somatic mutations were identified in 4 out of the 101 (4.0%) samples: 2 in-frame deletions in CARD10 (c.785_790delAGGAGA, p.K272_E273delKE; c.785_802delAGGAGAAGGAGAAGGAGA, p.K272_V277delKEPDNV) and 2 heterozygous missense mutations in CARD11 (c.49G>T, p.D17Y; c.160G>C, p.E54Q). The sample with CARD10 p.K272_E273delKE deletion was obtained from a 47-year-old patient who was also diagnosed with uterine leiomyoma, while the CARD10 p.K272_V277delKEPDNV-mutated sample was from a 43-year-old patient exhibiting a decreased blood eosinophil granulocyte ratio (0.3%) and an elevated serum creatine kinase level (314 U/l). The patient with the CARD11 p.D17Y mutation was 38 years old and exhibited an increased level of cancer antigen 125 (45.4 U/ml), while the patient with the CARD11 p.E54Q mutation was 46 years old and exhibited no other gynecological conditions. Evolutionary conservation analysis and online prediction programs suggested that these mutations may be disease-causing. In summary, 4 novel somatic mutations in the CARD10 and CARD11 genes were identified from amongst 101 cases of ovarian endometriosis for the first time, these mutations may serve active roles in the development of ovarian endometriosis.

16.
Gene ; 673: 119-129, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-29890312

RESUMO

Bone morphogenetic proteins (BMPs), which belong to the transforming growth factor-ß superfamily, have been implicated in various biological and physiological processes, especially in the gonad development. However, scarce studies were focused on the roles of BMPs in the reproductive system of crustaceans. In this study, the whole gene encoding BMP7 protein was cloned and characterized firstly in Chinese mitten crab Eriocheir sinensis. The bioinformatics analysis of the deduced amino acid sequence showed that Es-BMP7 was composed of prodomain/latency-associated peptide and the TGF-ß characteristic domain. The sequence conservation and phylogenetic analysis were also conducted. Quantitative real-time PCR was conducted indifferent tissues. The highest expression in testis indicated the potential role of BMP7 to male gonad development. Western blot results showed the different translational levels of BMP7 in different tissues. In-situ hybridization revealed that the expression of es-bmp7 signals presented in a bimodal manner: highest in spermatogonia, decreased in spermatocytes and stage I spermatids, disappeared in stage II spermatids, and showed up again in stage III spermatids and mature sperm. To further verify the potential roles during spermatogenesis, immunofluorescence was conducted and results showed the similar expression tendency with in situ hybridization. The protein signal was highest in the cytoplasm of spermatogonia, continued to decline in the cytoplasm of spermatocytes and the following stages, and weak signal was found in the mature sperm. Taken together, our results revealed that Es-BMP7 might play a part in testis development in Eriocheir sinensis, presumably by maintaining the self-renewal of spermatogonia and promoting the germ cell differentiation/meiotic mitosis, or facilitating the successful fertilization.


Assuntos
Proteínas de Artrópodes/metabolismo , Proteína Morfogenética Óssea 7/metabolismo , Braquiúros/genética , Espermatogênese , Testículo/metabolismo , Animais , Proteínas de Artrópodes/genética , Proteína Morfogenética Óssea 7/genética , Braquiúros/metabolismo , Diferenciação Celular , Clonagem Molecular , Primers do DNA , Perfilação da Expressão Gênica , Células Germinativas/metabolismo , Masculino , Filogenia , RNA/metabolismo , Espermátides/metabolismo , Espermatócitos/metabolismo , Espermatogônias/metabolismo , Testículo/embriologia , Fatores de Tempo
17.
Gynecol Oncol ; 149(3): 539-544, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29653688

RESUMO

BACKGROUND: To re-evaluate the efficacy of the prognostic factors currently employed in the treatment of malignant gestational trophoblastic neoplasia. METHODS: Clinical data from the Gestational Trophoblastic Disease (GTD) Center at Peking Union Medical Hospital (PUMCH) collected between January 2002 and December 2013 were retrospectively analyzed. Univariate and multivariate analyses of prognostic factors were performed using the Cox proportional hazards model. A new hazard ratio (HR)-based prognostic scoring scale was established and compared with the original scoring system. RESULTS: In total, 1420 cases were included in the study (median follow-up=40months, overall complete remission (CR) rate=95.8%, relapse rate=7.1%, mortality rate=5.5%, median disease-free survival (DFS)=36months). Low-risk (0-6 points) and high-risk (≥6 points) patients exhibited CR rates of 99.8% (915/917) and 88.5% (445/503) and mortality rates of 0.3% and 15.1% (P<0.001), respectively. Univariate and multivariate analyses showed that age, pretreatment serum levels of human chorionic gonadotropin beta-subunit (ß-hCG) and maximum tumor diameter were not independent prognostic risk factors. Antecedent pregnancy, the interval from the index pregnancy, the number of metastases and a history of failed chemotherapy treatments were independent prognostic risk factors. By modifying the scoring system based on the variables identified in a Cox analysis, we significantly increased the area under the receiver operating characteristics (ROC) curve. CONCLUSION: Though effective, the accuracy of the International Federation of Gynecology and Obstetrics (FIGO) 2000 Trophoblastic Neoplasia Staging System requires improvement. Irrelevant prognostic factors should be removed, and the weights of other factors should be adjusted appropriately.


Assuntos
Doença Trofoblástica Gestacional/patologia , Adulto , China/epidemiologia , Feminino , Doença Trofoblástica Gestacional/diagnóstico por imagem , Doença Trofoblástica Gestacional/epidemiologia , Humanos , Análise Multivariada , Estadiamento de Neoplasias , Gravidez , Modelos de Riscos Proporcionais , Estudos Retrospectivos
18.
Aging (Albany NY) ; 10(3): 305-321, 2018 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-29500332

RESUMO

Most of the mammalian follicles undergo a degenerative process called "follicle atresia". Apoptosis of granulosa cells is the main characteristic of follicle atresia. Follicle stimulating hormone (FSH) and the transforming growth factor ß (TGF-ß) superfamily have important regulatory functions in this process. FSH activates protein kinase A and cooperating with insulin receptor substrates, it promotes the PI3K/Akt pathway which weakens apoptosis. Both Smad or non-Smad signaling of the transforming growth factor ß superfamily seem to be related to follicle atresia, and the effect of several important family members on follicle atresia is concluded in this article. FSH and TGF-ß are likely to mutually influence each other and what we have already known about the possible underlying molecular mechanism is also discussed below.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Atresia Folicular/fisiologia , Folículo Ovariano/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Feminino , Hormônio Foliculoestimulante/genética , Regulação da Expressão Gênica/fisiologia , Humanos , Fator de Crescimento Transformador beta/genética
19.
Gene ; 660: 28-40, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29574191

RESUMO

Sperm malformation is one of the main reasons for male infertility, but the precise mechanisms of this process remain undiscovered. The major process of spermiogenesis is sperm head shaping. Cytoskeleton is a crucial unit in this process, as the acroplaxome and manchette are two kinds of momentous structures cooperated with various functional proteins to insure the formation of acrosome and nucleus. One is primarily formed by filamentous actin (F-actin) and responsible for transverse acrosome extension and concentration, another plays as the mainstay of nuclear deformation through circular arrangement of microtubules (MTs). We suspect that the acroplaxome alone cannot maintain such a spatial framework of the acrosome. Previous studies have also revealed that a nucleus without acrosome could not induce the formation of ectoplasmic specialization. In this review, we integrated most of the key proteins that have been proven to participate in the essential developmental steps of post-meiosis. We also propose that the ambient MTs of the acrosome might be emanated from the Golgi apparatus. They form a novel cytoskeleton termed acroframosome (AFS) to transport vesicles and proteins during acrosome biogenesis. The hypothesis of the acroframosome-acroplaxome-manchette (AAM) cytoskeletal system is likely to be the axis of head-to-tail spermiogenesis.


Assuntos
Actinas/metabolismo , Núcleo Celular/metabolismo , Fertilidade/fisiologia , Microtúbulos/metabolismo , Cabeça do Espermatozoide/metabolismo , Animais , Humanos , Masculino
20.
J Mass Spectrom ; 53(3): 234-239, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29314422

RESUMO

The determination of pesticide residues is an indispensable task in controlling food safety and environment protection. Carbendazim is one of the extensive uses of pesticides in the agricultural industry. In this study, a simple method utilizing syringe filter has been applied as electrospray ionization emitter for mass spectrometric identification and quantification of carbendazim in complex matrices including soil, natural water, and fruit juice samples, which contain many insoluble materials. With online syringe filter of the complex samples, most of insoluble materials such as soil were excluded in spray ionization process due to the filter effect, and analytes were subsequently sprayed out from syringe needle for mass spectrometric detection. The pore sizes of filters and diameters of syringe needles also were investigated. The analytical performances, including the linear range (1-200 ng·mL-1 ), limit of detection (0.2-0.6 ng·mL-1 , S/N > 3), limit of quantitation (3.5-8.6 ng·mL-1 , S/N > 10), reproducibility (6.4%-12.5%, n = 6), and recoveries (72.1%-91.0%, n = 6) were well acceptable for direct analysis of raw samples. Matrix effect for detection of carbendazim in soil samples also was experimentally investigated. This study demonstrated that syringe filter needle coupled with electrospray ionization mass spectrometry is a simple, efficient, and sensitive method for detection of pesticide residues in water, soil, and fruit juice for risk assessment.


Assuntos
Benzimidazóis/análise , Carbamatos/análise , Poluentes Ambientais/análise , Resíduos de Praguicidas/análise , Cromatografia Líquida de Alta Pressão , Sucos de Frutas e Vegetais/análise , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Solo/química , Espectrometria de Massas por Ionização por Electrospray , Seringas , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise
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