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To combine both electride and alkalide characteristics in one molecular switch, it is shown herein that the phenalenyl radical and the M3 ring (M3-PHY, M = Li, Na, and K) stacked with parallel and vertical geometries are good candidates. The former geometry is the superalkali electride e-â¯M3+-PHY while the latter geometry is the superalkalide Mδ--M2(1-δ)+-PHY-. The superalkalide Mδ--M2(1-δ)+-PHY- may isomerize to the superalkali electride e-â¯M3+-PHY (M = Li, Na, and K) using suitable long-wavelength irradiation, while the latter may isomerize to the former with suitable short-wavelength irradiation. Also, applying suitable oriented external electric fields can drive the superalkalide Mδ-M2(1-δ)+-PHY- to change into the superalkali electride e-â¯M3+-PHY (M = Li, Na, and K). The differences in the static and dynamic first hyperpolarizability (ß0) values between them were also studied.
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The exploration of innovative molecular switches has resulted in large developments in the field of molecular electronics. Focusing on a single molecular switch with different forms exhibiting different electride features, potassium-atom-doped all-cis 1,2,3,4,5,6-hexafluorocyclohexane K-F6C6H6 was studied theoretically. It was found that an oriented external electric field can drive excess electron transfer from the region outside of the K atom to that outside of F6C6H6. Subsequently, the electride-like molecule K-F6C6H6 (1) switches into the molecular electride K-F6C6H6e- (3) through another electride-like molecule K-F6C6H6 (2). The static first hyperpolarizabilities (ß0) are increased over 12- and 5-fold when moving from 1 to 2 and 3, respectively. The rise of each ß0 value constitutes an order of magnitude improvement. Between them, the different ß0 values suggest that K-F6C6H6 is a good candidate for use as a multiple-response nonlinear optics switch. The order of the ß0 values of 1-4 for M-F6C6H6 (M = Li and Na) coincide with that of K-F6C6H6, also exhibiting a switch effect.
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A novel intra-molecular self-redox switch, Li3N3Mg, is constructed theoretically. Our investigation showed that a suitably oriented external electric field (OEEF) can drive a long-range excess electron transfer from Mg atoms to Li3 rings. And subsequently, an interesting intra-molecular self-redox from Li32+N33-Mg+ to Li3+N33-Mg2+ accompanying the large different electronic static first hyperpolarizability (ß) is exhibited. The increase of the ß value constitutes an order of magnitude improvement from Li32+N33-Mg+ (34 986 a.u.) to Li3+N33-Mg2+ (101 225 a.u.), which indicates that Li3N3Mg is a good candidate for a self-redox NLO molecular switch.
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Gelatinization and retrogradation characteristics of starches from tigernut (Cyperus esculentus) tuber before and after various oil extraction processes were studied in this investigation. The results indicated that starches isolated from tigernut tuber after the various oil extraction processes varied significantly in gelatinization and retrogradation properties. The starches isolated from the cakes of tigernut tuber after hot press extraction exhibited higher retrogradation tendency and relatively less shear-thinning than other starch samples. The results of FT-IR, XRD, and NMR analysis indicated that oil extraction had an unfavorable influence on starch retrogradation, which may be due to structural changes caused by oil extraction processes. In particular, oil extraction led to more efficient packing of double helices in the crystalline lamella of the starches during storage. Retrogradation of the starch gels also reduced the water holding capacities of the starches. The starch sample isolated from the cake after cold press extraction exhibited the highest water absorption capacity among the five samples for all storage times. This investigation provides valuable novel information for the industrial utilization of tigernut tuber starches isolated from meals and cakes after oil extraction.
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Cyperus/química , Gelatina/química , Óleos de Plantas/isolamento & purificação , Tubérculos/química , Amido/química , Fracionamento Químico/métodos , Cristalização , Tecnologia de Alimentos , Géis/química , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Pomadas/química , Óleos de Plantas/química , Reologia , Resistência ao Cisalhamento , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/isolamento & purificação , Amido/ultraestrutura , Termogravimetria , Viscosidade , Água/química , Difração de Raios XRESUMO
The objective of the present investigation was to compared the structural and functional properties of starch isolated from fresh raw Chinese yam (FYS) and the Chinese yam after freeze-drying pretreatment (FDS), after hot-air drying pretreatment (HADS), after subcritical dimethyl ether dewaterization pretreatment (SDDS). Freeze-drying (FD) process reduced the short-and long-range molecular order of Chinese yam starch. Hot-air drying (HAD) process promoted the formation of ordered structure of starch granules. SEM images displayed the presence of protein-starch complexes in the HADS and SDDS samples. The FDS had the smallest Mw of amylopectin with 4.09 × 106 g/mol, but the Mw values of amylose molecules for FYS was highest. The branch chain length of amylopectin in HADS had a smaller proportion of short chains and less long chains and higher proportion of long chains compared with other starches. These molecular structure changes caused by the various drying pretreatment processes, resulting in the difference in functional properties including solubility and swelling power, gelatinization parameters, pasting characteristics and rheological properties. This study provided important information for the suitable application of starches isolated from various dried Chinese yam.
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Dessecação/métodos , Dioscorea/química , Amido/química , Cor , Peso Molecular , Tamanho da Partícula , Reologia , Solubilidade , Amido/isolamento & purificaçãoRESUMO
Asthenozoospermia is the most common clinical symptom of male infertility. Molecular markers associated with asthenozoospermia spermatozoa are scarcely identified. The objective of this study was to screen the differentially expressed genes (DEGs) in asthenozoospermia spermatozoa and assess the underlying bioinformatics roles in regulation of sperm quality.Based on gene expression omnibus (GEO) database, the GSE22331, GSE1133, and GSE4193 expression profile data were downloaded. The DEGs of asthenozoospermia spermatozoa were identified. Germ cell specific genes in DEGs were further screened. Then, gene ontology (GO) and over-representation analysis of DEGs were performed, followed by protein-protein interaction (PPI) network analysis. Expressions of selected genes of TEX11, ADAMTS5, ASRGL1, GMCL1, PGK2, KLHL10 in normozoospermia and asthenozoospermia spermatozoa were identified using real time Reverse Transcription-Polymerase Chain Reaction (RT-PCR).A total of 1323 DEGs were identified, including 1140 down-regulated genes. Twenty one and 96 down-regulated genes were especially expressed in spermatogonia and round spermatids, suggesting their testicular origins and influences on sperm quality. Bioinformatics analysis showed enriched functions of ubiquitin-like protein transferase or protein binding activities in down-regulated genes. Expressions of selected genes were validated by RT-PCR, which was consistent with bioinformatical results.The present study provided a novel insight into the understanding of sperm quality, and a potential method and dataset for the diagnosis and assessment of sperm quality in the event of male infertility.
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Astenozoospermia/genética , Astenozoospermia/metabolismo , Espermatozoides/metabolismo , Adulto , Biologia Computacional , Simulação por Computador , Expressão Gênica , Humanos , Masculino , RNA Mensageiro/metabolismoRESUMO
Teratospermia is a heterogeneous and complex disorder, which is closely associated with male fertility. Genes and gene products associated with teratospermia may serve as targeted biomarkers that help understand the underlying mechanisms of male infertility; however, systematic information on the subject remains to be elucidated. The present study performed a comparative bioinformatics analysis to identify biomarkers associated with sperm quality, particular focusing on testisspecific biomarkers. A stepwise screening approach identified 1,085 testis/epididymisspecific genes and 3,406 teratospermiaassociated genes, resulting in 348 testisspecific genes associated with aberrant sperm quality. These genes were functionally associated with the reproduction process. Gene products corresponding to heat shock protein family A (Hsp70) member 4 like (HSPA4L) and phosphoglycerate kinase 2 were characterized at the cellular level in human testes and ejaculated spermatozoa. HSPA4L expression in sperm was revealed to be associated with sperm quality. The present study provided a novel insight into the understanding of sperm quality, and a potential method for the diagnosis and assessment of sperm quality in the event of male infertility.
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Expressão Gênica , Estudos de Associação Genética , Espermatozoides/fisiologia , Testículo/metabolismo , Adulto , Biologia Computacional/métodos , Bases de Dados de Ácidos Nucleicos , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Imuno-Histoquímica , Infertilidade Masculina/genética , Masculino , Proteoma , Proteômica/métodos , Teratozoospermia/genéticaRESUMO
Notch3 receptor is expressed in a variety of cancers and the excised active intracellular domain (N3ICD) initiates its signaling cascade. N-acetylcysteine (NAC) as an antioxidant has been implicated in cancer prevention and therapy. In this study, we demonstrated a negative regulation of Notch3 by NAC in cancer cells. HeLa cells treated with NAC exhibited a time- and concentration-dependent decrease in Notch3 levels and its downstream effectors Hes1 and HRT1 in a manner independent of f-secretase or glutathione. In contrast, NAC did not affect protein levels of Notch1, the full length Notch3 precursor, or ectopically expressed N3ICD. Although SOD, catalase and NAC suppressed reactive oxygen species in HeLa cells, the first two antioxidants did not impact on Notch3 levels. While the mRNA expression of Notch3 was not altered by NAC, functional inhibition of lysosome, but not proteasome, blocked the NAC-dependent reduction of Notch3 levels. Furthermore, results from Notch3 silencing and N3ICD overexpression demonstrated that NAC prevented malignant phenotypes through down-regulation of Notch3 protein in multiple cancer cells. In summary, NAC reduces Notch3 levels through lysosome-dependent protein degradation, thereby negatively regulates Notch3 malignant signaling in cancer cells. These results implicate a novel NAC treatment in sensitizing Notch3-expressing tumors.
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Acetilcisteína/farmacologia , Lisossomos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptor Notch3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Acetilcisteína/uso terapêutico , Secretases da Proteína Precursora do Amiloide/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Catalase/metabolismo , Proteínas de Ciclo Celular/metabolismo , Regulação para Baixo , Técnicas de Silenciamento de Genes , Glutationa/metabolismo , Células HeLa , Humanos , Células MCF-7 , Neoplasias/tratamento farmacológico , Complexo de Endopeptidases do Proteassoma/metabolismo , Domínios Proteicos , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Receptor Notch1/metabolismo , Receptor Notch3/genética , Superóxido Dismutase/metabolismo , Fatores de Transcrição HES-1/metabolismoRESUMO
STUDY QUESTION: Is there an association between the expression of phosphoglycerate kinase (PGK) 2 in spermatozoa and sperm quality in both elderly men and young asthenozoospermia patients? SUMMARY ANSWER: Spermatozoa from elderly men and young asthenozoospermia patients show decreased expression of PGK2, which has a close positive relationship with sperm quality. WHAT IS KNOWN ALREADY: PGK1 and PGK2 are involved in spermatogenesis and thought to be related to sperm motility. However, limited information is known about their temporal-spatial expression in human spermatogenesis and their relationship with sperm quality. STUDY DESIGN, SIZE, DURATION: This was a case-control study including 30 healthy young males (aged 28-31 years), 30 elderly men (aged 68-70 years), and 30 asthenozoospermic patients (aged 25-40 years, progressive motility <32%) who donated semen samples. Furthermore, young testes samples were obtained from five fathers (27-33 years old) who had died in car accidents, while aged testes samples were obtained from five elderly fathers (78-82 years old) who were prostate cancer patients. PARTICIPANTS/MATERIALS, SETTING, METHODS: Semen samples from young adults, elderly men and asthenozoospermic patients were prepared, and their parameters were assessed by Computer-Aided Sperm Analysis (CASA). Sperm proteins were extracted for western blot analysis. Immunohistochemistry was used to characterize the cellular localization of PGK1 and PGK2 in testes samples. Sperm immunofluorescence quantification experiments identified the differential expression of PGK1 and PGK2 in sperm from young adults, elderly men and asthenozoospermic patients. Antibodies against PGK1 and PGK2 were used to test their influence on sperm motility and penetration into viscous media. A modified Kremer test using methyl cellulose was adopted to assess sperm function via penetration into viscous media. MAIN RESULTS AND THE ROLE OF CHANCE: Cellular localization analysis showed that PGK1 was mainly expressed in spermatogonia whereas PGK2 was mainly expressed in round spermatids. Expression levels of both PGKs were significantly decreased in the testis with ageing (P < 0.05). Western blot and immunofluorescence quantification showed markedly lower expression of PGK2 (P < 0.05) in sperm from elderly men or asthenozoospermic patients compared sperm from with healthy young men. Sperm functional analysis validated the close relationship between expression of PGK2 and sperm motility (staining percentage, r = 0.60, P < 0.05; intensity, r = 0.59, P < 0.05). Use of an anti-PGK2 antibody on sperm significantly decreased their ability to penetrate into a cervical mucus substitute (P < 0.05). LIMITATIONS, REASONS FOR CAUTION: Before any clinical applications using PGK2 to assess sperm quality can be developed, more cases should be used to evaluate this approach. WIDER IMPLICATIONS OF THE FINDINGS: The study provides new insights into the role of PGKs in male reproduction. The results also indicate that PGK2 is a promising molecular candidate for the assessment of sperm quality and the screening of male contraceptive targets. STUDY FUNDING/COMPETING INTERESTS: This work was supported by grants from the National Natural Science Foundation of China (no. 81300533, 81370013 and 81000277) and Shandong Provincial Natural Science Foundation, China (ZR2013HQ002). The authors declare no competing financial interests.
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Astenozoospermia/metabolismo , Isoenzimas/metabolismo , Fosfoglicerato Quinase/metabolismo , Espermatozoides/fisiologia , Testículo/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Estudos de Casos e Controles , Humanos , Masculino , Análise do Sêmen , EspermatogêneseRESUMO
The mammalian spermatozoon acquires its fertilising potential during transit through the epididymis, where it interacts with epididymal luminal fluid proteins (the sperm maturation milieu). In order to highlight the epididymal-specific function of the rhesus monkey (Macaca mulatta) in sperm maturation, two-dimensional gel electrophoresis of epididymal luminal fluid proteins was followed by identification by Matrix-Assisted Laser Desorption/ Ionization Time of Flight Mass Spectrometry (MALDI-TOF/MS) or MALDI-TOF/TOF and revealed over five hundred spots, comprising 198 non-redundant proteins. Some mass spectrometric data were confirmed by western blotting identification. Some common epididymal fluid proteins were identified, such as clusterin, α-1-antitrypsin, malate dehydrogenase, L-lactate dehydrogenase B, α-1-acid glycoprotein 1 and α-mannosidase. More than 7% of all proteins were anti-oxidative, which might control oxidative stress within the male tract. When compared with bull and human epididymal luminal fluid proteins, those in the rhesus monkey had more overlap with the human, which provides evidence of a close evolutionary relationship between the rhesus monkey and man. This study provides new proteomic information on possible rhesus monkey epididymal functions and novel potential biomarkers for the noninvasive assessment of male fertility.
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Epididimo/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Macaca mulatta/fisiologia , Mucosa/metabolismo , Proteoma/metabolismo , Espermatogênese , Espermatozoides/metabolismo , Animais , Animais de Zoológico , Western Blotting/veterinária , Secreções Corporais/metabolismo , China , Biologia Computacional , Eletroforese em Gel Bidimensional/veterinária , Epididimo/citologia , Evolução Molecular , Perfilação da Expressão Gênica/veterinária , Concentração de Íons de Hidrogênio , Masculino , Mucosa/citologia , Estresse Oxidativo , Especificidade da Espécie , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária , Espermatozoides/citologia , Espectrometria de Massas em Tandem/veterináriaRESUMO
ß-catenin is an integral part of the Wnt signaling pathway and has been linked to tumorigenesis and multiple developmental processes. The high ß-catenin expression with low tumor incidence in the human epididymis is thus intriguing. In the present study, the ß-catenin gene and protein was found to be highly expressed in the murine caput epididymidis, and the protein mainly localized along the lateral plasma membranes of adjacent epithelial cells throughout both human and mouse epididymides. Furthermore, the adult mouse epididymis was found to express almost all the Wnt/ß-catenin signaling pathway genes that were determined previously by our group in the human organ. Despite the differences in epididymal structure, the similar location of ß-catenin and the high concordance of this pathway's components' gene expression in both the adult human and mouse epididymides make the mouse a suitable animal model for studying the anti-tumor mechanism of the epididymis. In addition, both the mRNA and protein expression of ß-catenin shared a similar spatial expression as the mRNA of Ros1, a proto-oncogene and a key developmental regulator of the initial segment of the mouse epididymis. The observations on the parallel temporal expression of ß-catenin and Ros1 during postnatal development raise the possibility that the canonical Wnt signaling pathway has an additional role in the postnatal development of mouse epididymis.
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Epididimo/metabolismo , Receptores Frizzled/genética , Expressão Gênica , RNA Mensageiro/metabolismo , Proteínas Wnt/genética , Via de Sinalização Wnt/genética , beta Catenina/genética , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Animais , Western Blotting , Receptores Frizzled/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Camundongos , Proteínas Tirosina Quinases/genética , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição TCF/genética , Fatores de Transcrição TCF/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismoRESUMO
Genetic variations of ALDH2, encoding aldehyde dehydrogenase-2 which regulates aldehyde oxidation in the brain, have been recently suggested to impact on the association of pesticide exposure with Parkinson's disease (PD). However, the link between ALDH2 polymorphism and PD remains elusive. In the present study, tag-single nucleotide polymorphisms of ALDH2, including rs4767944, rs441, and rs671, were extracted and analyzed in a Chinese cohort consisting of 584 PD patients and 582 controls. Results from genotyping analyses showed that rs4767944 (p = 0.002), but not rs441 and rs671, were associated with PD. The C allele of rs4767944 served a risk factor toward PD. Further analysis presented a significant association between haplotype frequencies and the risk for PD, primarily driven by the preponderance of the C-T-A (p = 0.03) or C-T-G (p = 0.003) haplotype of rs4767944, rs441, and rs671 in PD patients. In conclusion, these novel results suggest an association between PD susceptibility and ALDH2 genetic variations.
Assuntos
Aldeído Desidrogenase/genética , Predisposição Genética para Doença/genética , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único/genética , Idoso , Aldeído-Desidrogenase Mitocondrial , Povo Asiático , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/etnologia , Estatísticas não ParamétricasRESUMO
Ahead of Print article withdrawn by publisher.
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STUDY QUESTION: Does a defect in the human sperm-located protein prostate and testis expressed 1 (PATE1) exist in both aged men and young asthenozoospermia patients? SUMMARY ANSWER: A defect in sperm PATE1 exists in both aged men and young asthenozoospermia patients, and an antibody against PATE1 can decrease human sperm motility and zona-free hamster oocyte penetration. WHAT IS KNOWN ALREADY: Both aged men and young asthenozoospermia patients have poor sperm quality. The PATE1 protein seems to mediate sperm-egg interactions; however, the mechanisms are still unknown. STUDY DESIGN, SIZE, DURATION: This was a case-control study including 60 young fathers (aged 28-32 years) and 60 aged fathers (68-72 years old) who donated semen by masturbation after 7 days of sexual abstinence. Comparative sperm proteome analysis from the young fathers and aged fathers was performed to discover key proteins. The target protein PATE1 was chosen and validated by western blotting and immunohistochemistry. Quantitative assessment of sperm PATE1 protein was performed on sperm from 60 young fathers, 60 aged fathers and 110 young asthenozoospermia patients. Furthermore, an antibody against PATE1 assay was used to test whether PATE1 participated in sperm motility and penetration of zona-free hamster egg. PARTICIPANTS/MATERIALS, SETTING, METHODS: Samples were pooled and separated by two-dimensional gel electrophoresis followed by identification by matrix-assisted laser desorption/ionization time of flight mass spectrometry. Western blotting and immunohistochemistry were used to validate the confidence of proteomic data. Sperm immunofluorescence quantification experiments disclosed whether the aged men indeed shared the same PATE1 defect with 110 young asthenozoospermia patients. The sperm motility test and penetration of zona-free hamster egg assay were performed for PATE1. MAIN RESULTS AND THE ROLE OF CHANCE: Twenty-two sperm proteins with significant differential expression between young adults and aged men were identified (P < 0.05, mean ratio >1.5), including 13 proteins with decreased expressions with aging. Based on bioinformatics, PATE1 was chosen for further study, and exhibited similar changes in expression level and localization on sperm from aged men and young asthenozoospermia patients. Antibody blocking revealed that PATE1 was involved in sperm-egg penetration and sperm motility. LIMITATIONS, REASONS FOR CAUTION: Before any clinical application of PATE1 as a biomarker for the diagnosis of male infertility, more cases should be used to evaluate confidence in this approach. WIDER IMPLICATIONS OF THE FINDINGS: This study revealed a common molecular basis underlying the decline in sperm quality in the natural aging process and in young men with asthenozoospermia. The data should greatly contribute to the development of molecular evaluation of sperm quality, and the diagnosis and treatment of asthenozoospermia. STUDY FUNDING/COMPETING INTERESTS: This work was supported by grants from the National Natural Science Foundation of China (NO. 81300533, 81370013 and 81000277) and Shandong Provincial Natural Science Foundation, China (ZR2013HQ002, ZR2014HQ068). The authors declare no competing financial interests.
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Envelhecimento , Astenozoospermia/genética , Astenozoospermia/metabolismo , Proteínas de Membrana/genética , Adulto , Fatores Etários , Idoso , Animais , Anticorpos/química , Estudos de Casos e Controles , Cricetinae , Eletroforese em Gel Bidimensional , Feminino , Humanos , Masculino , Oócitos/metabolismo , Proteômica , Motilidade dos Espermatozoides , Espermatozoides/metabolismo , Testículo/metabolismoRESUMO
PURPOSE: The aim of this study was to evaluate the suppression effect of survivin shRNA on the expression of the survivin gene in the human laryngeal cancer cell line Hep-2. PROCEDURES: 60 cases of laryngeal squamous-cell carcinoma (LSCC) and 10 cases of normal laryngeal mucosa were examined using immunohistochemistry to determine whether the expression of survivin correlated with tumorigenesis. Three plasmid vectors of short hairpin RNA (shRNA) specific for survivin were designed and generated. Western blot and real-time PCR analysis of survivin expression in Hep-2 cells was performed 48 h after transfection. The growth curve was used to determine the cell proliferation. Propidium iodide (PI) single staining was applied to detect the cell cycle. The apoptosis of the cells was analyzed by flow cytometry with the FITC-annexin-V/PI double staining and PI single staining. RESULTS: 68.33% (41 out of 60) of tumors were positive for survivin expression and significantly associated with lymph node metastasis and advanced stage. In contrast, no expression of survivin in normal mucosa was detected. Transfection of Hep-2 cells with survivin shRNA significantly inhibited survivin expression at both the mRNA and the protein level in Hep-2 cells. Downregulation of survivin resulted in increasing the apoptosis index, but the results showed no obvious influence on cell cycle. CONCLUSIONS: This study demonstrates that survivin shRNA effectively inhibits survivin gene expression in Hep-2 cells leading to growth suppression and apoptotic induction in Hep-2 cells.