Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 87
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Nano Lett ; 24(17): 5139-5145, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38639471

ABSTRACT

Dynamic tuning of thermal transport in solids is scientifically intriguing with wide applications for thermal transport control in electronic devices. In this work, we demonstrate a thermal transistor, a device in which heat flow can be regulated using external control, realized in a topological insulator (TI) through the topological surface states. The tuning of thermal transport is achieved by using optical gating of a thin dielectric layer deposited on the TI film. The gate-dependent thermal conductivity is measured using micro-Raman thermometry. The transistor has a large ON/OFF ratio of 2.8 at room temperature and can be continuously and repetitively switched in tens of seconds by optical gating and potentially much faster by electrical gating. Such thermal transistors with a large ON/OFF ratio and fast switching times offer the possibilities of smart thermal devices for active thermal management and control in future electronic systems.

2.
Nano Lett ; 24(40): 12433-12441, 2024 Oct 09.
Article in English | MEDLINE | ID: mdl-39351960

ABSTRACT

There is an increasing demand for p-type semiconductors with scalable growth, excellent device performance, and back-end-of-line (BEOL) compatibility. Recently, tellurium (Te) has emerged as a promising candidate due to its appealing electrical properties and potential low-temperature production. So far, nearly all of the scalable production and integration of Te with complementary metal oxide semiconductor (CMOS) technology have been based on physical vapor deposition. Here we demonstrate wafer-scale atomic layer-deposited (ALD) TeOx/Te heterostructure thin-film transistors with high uniformity and integration compatibility. The wafer-scale uniformity of the film is evidenced by spatial Raman mappings and statistical electrical analysis. Furthermore, surface accumulation-induced good ohmic contact has been observed and explained by the unique band alignment of the charge neutrality level inside the Te valence band. These results demonstrate ALD TeOx/Te as a promising p-type semiconductor for monolithic three-dimensional integration in BEOL CMOS applications incorporated with well-established n-type ALD oxide semiconductors.

3.
Reprod Biol Endocrinol ; 22(1): 78, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38987797

ABSTRACT

OBJECTIVE: To explore the optimal models for predicting the formation of high-quality embryos in Poor Ovarian Response (POR) Patients with Progestin-Primed Ovarian Stimulation (PPOS) using machine learning algorithms. METHODS: A retrospective analysis was conducted on the clinical data of 4,216 POR cycles who underwent in vitro fertilization (IVF) / intracytoplasmic sperm injection (ICSI) at Sichuan Jinxin Xinan Women and Children's Hospital from January 2015 to December 2021. Based on the presence of high-quality cleavage embryos 72 h post-fertilization, the samples were divided into the high-quality cleavage embryo group (N = 1950) and the non-high-quality cleavage embryo group (N = 2266). Additionally, based on whether high-quality blastocysts were observed following full blastocyst culture, the samples were categorized into the high-quality blastocyst group (N = 124) and the non-high-quality blastocyst group (N = 1800). The factors influencing the formation of high-quality embryos were analyzed using logistic regression. The predictive models based on machine learning methods were constructed and evaluated accordingly. RESULTS: Differential analysis revealed that there are statistically significant differences in 14 factors between high-quality and non-high-quality cleavage embryos. Logistic regression analysis identified 14 factors as influential in forming high-quality cleavage embryos. In models excluding three variables (retrieved oocytes, MII oocytes, and 2PN fertilized oocytes), the XGBoost model performed slightly better (AUC = 0.672, 95% CI = 0.636-0.708). Conversely, in models including these three variables, the Random Forest model exhibited the best performance (AUC = 0.788, 95% CI = 0.759-0.818). In the analysis of high-quality blastocysts, significant differences were found in 17 factors. Logistic regression analysis indicated that 13 factors influence the formation of high-quality blastocysts. Including these variables in the predictive model, the XGBoost model showed the highest performance (AUC = 0.813, 95% CI = 0.741-0.884). CONCLUSION: We developed a predictive model for the formation of high-quality embryos using machine learning methods for patients with POR undergoing treatment with the PPOS protocol. This model can help infertility patients better understand the likelihood of forming high-quality embryos following treatment and help clinicians better understand and predict treatment outcomes, thus facilitating more targeted and effective interventions.


Subject(s)
Machine Learning , Ovulation Induction , Progestins , Humans , Female , Ovulation Induction/methods , Retrospective Studies , Adult , Pregnancy , Progestins/pharmacology , Fertilization in Vitro/methods , Embryonic Development/drug effects , Embryonic Development/physiology , Sperm Injections, Intracytoplasmic/methods , Blastocyst/drug effects , Blastocyst/physiology , Embryo Transfer/methods , Pregnancy Rate
4.
Nano Lett ; 23(8): 3599-3606, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37057864

ABSTRACT

Chirality arises from the asymmetry of materials, where two counterparts are the mirror image of each other. The interaction between circular-polarized light and quantum materials is enhanced in chiral space groups due to the structural chirality. Tellurium (Te) possesses the simplest chiral crystal structure, with Te atoms covalently bonded into a spiral atomic chain (left- or right-handed) with a periodicity of 3. Here, we investigate the tunable circular photoelectric responses in 2D Te field-effect transistors with different chirality, including the longitudinal circular photogalvanic effect induced by the radial spin texture (electron-spin polarization parallel to the electron momentum direction) and the circular photovoltaic effect induced by the chiral crystal structure (helical Te atomic chains). Our work demonstrates the controllable manipulation of the chirality degree of freedom in materials.

5.
Nano Lett ; 23(18): 8445-8453, 2023 Sep 27.
Article in English | MEDLINE | ID: mdl-37677143

ABSTRACT

Tellurium (Te) is an elemental semiconductor with a simple chiral crystal structure. Te in a two-dimensional (2D) form synthesized by a solution-based method shows excellent electrical, optical, and thermal properties. In this work, the chirality of hydrothermally grown 2D Te is identified and analyzed by hot sulfuric acid etching and high-angle tilted high-resolution scanning transmission electron microscopy. The gate-tunable nonlinear electrical responses, including the nonreciprocal electrical transport in the longitudinal direction and the nonlinear planar Hall effect in the transverse direction, are observed in 2D Te under a magnetic field. Moreover, the nonlinear electrical responses have opposite signs in left- and right-handed 2D Te due to the opposite spin polarizations ensured by the chiral symmetry. The fundamental relationship between the spin-orbit coupling and the crystal symmetry in two enantiomers provides a viable platform for realizing chirality-based electronic devices by introducing the degree of freedom of chirality into electron transport.

6.
Phys Rev Lett ; 131(15): 150203, 2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37897772

ABSTRACT

Heisenberg-type measurement uncertainty relations (MURs) of two quantum observables are essential for contemporary research in quantum foundations and quantum information science. Going beyond, here we report the first experimental study of MUR of three quantum observables. We establish rigorously MURs for triplets of unbiased qubit observables as combined approximation errors lower bounded by an incompatibility measure, inspired by the proposal of Busch et al. [Phys. Rev. A 89, 012129 (2014)PLRAAN1050-294710.1103/PhysRevA.89.012129]. We develop a convex programming protocol to numerically find the exact value of the incompatibility measure and the optimal measurements. We propose a novel implementation of the optimal joint measurements and present several experimental demonstrations with a single-photon qubit. We stress that our method is universally applicable to the study of many qubit observables. Besides, we theoretically show that MURs for joint measurement can be attained by sequential measurements in two of our explored cases. We anticipate that this work may stimulate broad interests associated with Heisenberg's uncertainty principle in the case of multiple observables, enriching our understanding of quantum mechanics and inspiring innovative applications in quantum information science.

7.
Eur J Nutr ; 62(1): 395-406, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36056948

ABSTRACT

PURPOSE: Abnormal acetylation modification is a common epigenetic change in tumorigenesis and is closely related to the progression of colorectal cancer (CRC). Our previous studies have suggested that black raspberry (BRB) anthocyanins have a significant chemopreventive effect against CRC. This study investigated whether protein acetylation plays an important role in BRB anthocyanins-mediated regulation of CRC progression. METHODS: We used the AOM-induced CRC mouse model and the CRC cell lines SW480 and Caco-2 to explore the potential role of acetylation of histone H4 and NF-κB signaling pathway-related proteins (non-histone proteins) in the antitumor process mediated by BRB anthocyanins. The expression of related proteins was detected by western blot. ROS level was detected by immunofluorescence. RESULTS: BRB anthocyanins affected the acetylation level by down-regulating the expression of Sirtuin1 (SIRT1) and up-regulating the expression of MOF and EP300. The acetylation level of lysine sites on histone H4 (H4K5, H4K12 and H4K16) was increased. Furthermore, following BRB anthocyanins treatment, the expression of ac-p65 was significantly up-regulated and the NF-κB signal pathway was activated, which in turn up-regulated Bax expression and inhibited Bcl-2, cyclin-D1, c-myc and NLRP3 expression to promote CRC cell cycle arrest, apoptosis and relieve inflammation. CONCLUSION: The findings suggested that protein acetylation could play a critical role in BRB anthocyanins-regulated CRC development.


Subject(s)
Colorectal Neoplasms , Rubus , Humans , Mice , Animals , NF-kappa B/genetics , NF-kappa B/metabolism , Rubus/metabolism , Anthocyanins/pharmacology , Anthocyanins/therapeutic use , Sirtuin 1/genetics , Sirtuin 1/metabolism , Sirtuin 1/pharmacology , Histones , Caco-2 Cells , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/prevention & control , Cell Line, Tumor , Cell Proliferation
8.
Nano Lett ; 21(18): 7527-7533, 2021 Sep 22.
Article in English | MEDLINE | ID: mdl-34514803

ABSTRACT

Tellurium (Te) is a narrow bandgap semiconductor with a unique chiral crystal structure. The topological nature of electrons in the Te conduction band can be studied by realizing n-type doping using atomic layer deposition (ALD) technique on two-dimensional (2D) Te film. In this work, we fabricated and measured the double-gated n-type Te Hall-bar devices, which can operate as two separate or coupled electron layers controlled by the top gate and back gate. Profound Shubnikov-de Haas (SdH) oscillations are observed in both top and bottom electron layers. Landau level hybridization between two layers, compound and charge-transferable bilayer quantum Hall states at filling factor ν = 4, 6, and 8, are analyzed. Our work opens the door for the study of Weyl physics in coupled bilayer systems of 2D materials.

9.
Cytogenet Genome Res ; 161(3-4): 167-177, 2021.
Article in English | MEDLINE | ID: mdl-33951625

ABSTRACT

The barrier-to-autointegration factor (BAF) is widely expressed in most human tissues and plays a critical role in chromatin organization, nuclear envelope assembly, gonadal development, and embryonic stem cell self-renewal. Complete loss of BAF has been shown to lead to embryonic lethality and gonadal defects. The BAF paralog, namely, barrier-to-autointegration factor 2 (BANF2), exhibits a testis-predominant expression pattern in both humans and mice. Unlike BAF, it may cause isolated male infertility. Therefore, we used the CRISPR/Cas9 system to generate Banf2-knockout mice to further study its function in spermatogenesis. Unexpectedly, knockout mice did not show any detectable abnormalities in histological structure of the testis, epididymis, ovary, and other tissues, and exhibited normal fertility, indicating that Banf2 is not essential for mouse spermatogenesis and fertility.


Subject(s)
Fertility/genetics , Intracellular Signaling Peptides and Proteins/genetics , Nuclear Proteins/genetics , Spermatogenesis/genetics , Amino Acid Sequence , Animals , Base Sequence , CRISPR-Cas Systems , Female , Gene Expression Regulation, Developmental , Genes, Essential , Intracellular Signaling Peptides and Proteins/metabolism , Male , Mice, Inbred C57BL , Mice, Knockout , Nuclear Proteins/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Spermatozoa/metabolism , Testis/cytology , Testis/metabolism
10.
Mikrochim Acta ; 188(9): 291, 2021 08 06.
Article in English | MEDLINE | ID: mdl-34363101

ABSTRACT

A sensitive and turn-on fluorescence nanoprobe based on core-shell Ag@Au nanoparticles (Ag@AuNPs) as a fluorescence receptor and red emissive graphene quantum dots (GQDs) as a donor was fabricated. They were conjugated together through π-π stacking between the GQDs and single-strand DNA modified at the Ag@AuNPs surface. The absorption spectrum of the receptor significantly overlapped with the donor emission spectrum, leading to a strong Förster resonance energy transfer (FRET) and thus a dramatic quenching. The sensing mechanism relies on fluorescence recovery following DNA cleavage by •OH produced from Fenton-like reaction between the peroxidase-like Ag nanocore and H2O2. The red emissive feature (Ex/Em, 520 nm/560 nm) provides low background in physiological samples. The •OH production, great spectrum overlapping, and red emission together contributes to good sensitivity and living cell imaging capability. The fluorescence assay (intensity at 560 nm) achieves a low detection limit of 0.49 µM H2O2 and a wide linear range from 5 to 200 µM, superior to most of the reported fluorescent probes. The RSD value for 100 µM H2O2 was 1.4%. The nanoprobe exhibits excellent anti-interferences and shows low cytotoxicity. The recovery of 100 µM standard H2O2 in a cancer cell lysate was 85.8%. Most satisfactorily, it can realize monitoring and imaging H2O2 in living cells. This study not only presents a sensitive H2O2 probe but also provides a platform for detecting other types of reactive oxygen species.


Subject(s)
Fluorescent Dyes/therapeutic use , Gold/chemistry , Graphite/chemistry , Hydrogen Peroxide/chemistry , Metal Nanoparticles/chemistry , Quantum Dots/chemistry , Silver/chemistry , Humans
11.
Aesthetic Plast Surg ; 45(2): 564-569, 2021 04.
Article in English | MEDLINE | ID: mdl-31637503

ABSTRACT

BACKGROUND: The epicanthal fold is ordinary in the eyelids of Asians, and the aesthetic appearance of eyelid surgery could be reduced and undermined; thus, medial epicanthoplasty is commonly performed to eliminate the effect of the epicanthal fold with less scarring. At present, there are a lot of techniques that have been described for the treatment of epicanthal fold. The potential problems, however, such as visible scar or under correction in the medial canthus area are challenges to surgeons. The purpose of our study was to explore a novel and individualized design using a modified rectangle flap with acceptable functional and aesthetic outcomes. METHODS: From January 2017 to January 2018, epicanthoplasty was performed for 40 patients by using a modified rectangle flap. All patients underwent double-eyelid surgery at the same time when they needed it. The evaluation criteria included the intercanthal distance (ICD), interpupillary distance (IPD), the ratio of ICD to IPD (ICD ratio), scar visibility, and cosmetic results. RESULTS: From January 2017 to January 2018, the modified rectangle flap method was carried out on 40 patients, who were evaluated at follow-up from 7 to 15 months. The average intercanthal length was 36.9 ± 2.2 mm preoperatively and decreased significantly to 31.5 ± 1.8 mm postoperatively, 7 months after the surgery (P < 0.01). The excellent cosmetic results, in terms of an open medial canthus, were observed during follow-up periods, with no definite recurrence, hypertrophic scar, or injury of the lacrimal apparatus. The inner canthus and lacrimal caruncle are fully exposed with an invisible scar. Both the patients and the surgeon judged that the aesthetic outcomes were excellent or good. CONCLUSIONS: This modified rectangular flap is an effective and personalized method of correcting the medial folds that leave no additional scar in the medial canthal area, and the procedure meets the patient's aesthetic expectations. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Subject(s)
Blepharoplasty , Asian People , Cohort Studies , Eyelids/surgery , Humans , Retrospective Studies , Treatment Outcome
12.
Yi Chuan ; 42(6): 524-535, 2020 Jun 20.
Article in Zh | MEDLINE | ID: mdl-32694111

ABSTRACT

The structure of sperm tail is closely related to its motor function, which directly determines whether the sperm can be normally transported to fallopian tube and fertilize the ovum. The formation and development of sperm tail is a very complex process, which is finely regulated by various kinds of proteins. Research finds that defects of various sperm tail development related proteins can lead to oligospermia, asthenozoospermia and teratospermia. Based on the ultrastructure of sperm tail, we summarize the recent research progress of the proteins related to sperm tail development, thereby providing the theoretical basis and practical possibility for the diagnosis and treatment of male infertility.


Subject(s)
Asthenozoospermia , Sperm Tail , Female , Humans , Male , Sperm Maturation , Sperm Motility , Spermatozoa
13.
BMC Microbiol ; 19(1): 229, 2019 10 22.
Article in English | MEDLINE | ID: mdl-31640545

ABSTRACT

BACKGROUND: The gut bacteria of tephritid fruit flies play prominent roles in nutrition, reproduction, maintenance and ecological adaptations of the host. Here, we adopted an approach based on direct observation of symbiotic or axenic flies feeding on dishes seeded with drops of full diet (containing all amino acids) or full diet supplemented with bacteria at similar concentrations to explore the effects of intestinal bacteria on foraging decision and fitness of Bactrocera dorsalis. RESULTS: The results show that intestinal probiotics elicit beneficial foraging decision and enhance the female reproduction fitness and survival of B. dorsalis (symbiotic and axenic), yet preferences for probiotic diets were significantly higher in axenic flies to which they responded faster compared to full diet. Moreover, females fed diet supplemented with Pantoea dispersa and Enterobacter cloacae laid more eggs but had shorter lifespan while female fed Enterococcus faecalis and Klebsiella oxytoca enriched diets lived longer but had lower fecundity compared to the positive control. Conversely, flies fed sugar diet (negative control) were not able to produce eggs, but lived longer than those from the positive control. CONCLUSIONS: These results suggest that intestinal bacteria can drive the foraging decision in a way which promotes the reproduction and survival of B. dorsalis. Our data highlight the potentials of gut bacterial isolates to control the foraging behavior of the fly and empower the sterile insect technique (SIT) program through the mass rearing.


Subject(s)
Bacteria/growth & development , Tephritidae/microbiology , Tephritidae/physiology , Animals , Appetitive Behavior , Bacteria/genetics , Female , Fertility , Genetic Fitness , Longevity , Male , Symbiosis , Tephritidae/genetics
14.
BMC Microbiol ; 19(Suppl 1): 285, 2019 12 24.
Article in English | MEDLINE | ID: mdl-31870291

ABSTRACT

BACKGROUND: Symbiotic bacteria play a critical role in insect's biology. They also offer great opportunities to improve on current pest management techniques. In order to exploit and integrate the roles played by the gut microbiota on pest management programs, a better understanding of the structural organization of the microbial community in the Chinese citrus fly Bactrocera minax is essential. RESULTS: The results revealed a total of 162 OTUs at 97% similarity interval. The dominant bacteria phyla were Proteobacteria, Bacteroidetes, Antinobacteria and Firmicutes, with the Proteobacteria having the highest relative abundance (more than 80% in all life stages). There was also a shift in the dominant OTUs from the early developmental stages to the late developmental stages and adult stages in B. minax. These OTUs related to Klebsiella pneumoniae, Providencia rettgeri and Enterobacter aerogenes, respectively. Six bacteria OTU were shared by all the life stages. These belonged to the Enterobacteriaceae and the Enterococcaceae families. CONCLUSION: The common bacteria groups shared by all the life stages and other fruit flies could be important targets for further research. This should aim towards realizing how these bacteria affect the biology of the fly and how their relationship could be exploited in the development of sustainable management strategies against fruit flies.


Subject(s)
Bacteria/classification , Citrus/parasitology , RNA, Ribosomal, 16S/genetics , Tephritidae/growth & development , Animals , Bacteria/genetics , Bacteria/isolation & purification , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Female , Gastrointestinal Microbiome , Male , Pest Control, Biological , Phylogeny , Symbiosis , Tephritidae/microbiology
15.
J Asian Nat Prod Res ; 21(4): 299-307, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30909734

ABSTRACT

Six new glycosides (1-6), together with three known ones, were isolated from the twigs and leaves of Rhododendron latoucheae. Their structures were elucidated based on the spectroscopic data, including infrared spectrometry, mass spectrometry, and nuclear magnetic resonance experiments, along with Mosher's method. In addition, all compounds were tested their antiviral (herpes simplex virus-1 and influenza A/95-359) activities.


Subject(s)
Glycosides/isolation & purification , Rhododendron/chemistry , Antiviral Agents/pharmacology , Glycosides/chemistry , Glycosides/pharmacology , Magnetic Resonance Spectroscopy , Plant Leaves/chemistry
16.
J Nat Prod ; 81(8): 1721-1733, 2018 08 24.
Article in English | MEDLINE | ID: mdl-30106288

ABSTRACT

A hyphenated NMR technique (analytical HPLC with a DAD connected to MS, SPE, and NMR) has proven effective for the full structural analysis and identification of minor natural products in complex mixtures. Application of this hyphenated technique to the CH2Cl2-soluble fraction of Rhododendron latoucheae led to the identification of 15 new minor ursane-type 28-nortriterpenoids (1-15). Compounds 1 and 12 inhibited HSV-1 with IC50 values of 6.4 and 0.4 µM, respectively.


Subject(s)
Plant Components, Aerial/chemistry , Plant Leaves/chemistry , Rhododendron/chemistry , Triterpenes/chemistry , Animals , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Chlorocebus aethiops , Chromatography, High Pressure Liquid , Dogs , Herpesvirus 1, Human/drug effects , Influenza A virus/drug effects , Madin Darby Canine Kidney Cells , Magnetic Resonance Spectroscopy , Mass Spectrometry , Molecular Structure , Plant Extracts/chemistry , Solid Phase Extraction , Triterpenes/pharmacology , Vero Cells
17.
Yi Chuan ; 40(9): 724-732, 2018 Sep 20.
Article in Zh | MEDLINE | ID: mdl-30369476

ABSTRACT

Spermatogenesis requires both germ cells and testicular somatic cells, which are also involved in testicular development and male fertility. Sertoli cells are the only somatic cells in the seminiferous tubules and play very important roles in normal spermatogenesis. Abnormality of Sertoli cells in proliferation and adhesion may induce aberrant spermatogenesis and eventually cause infertility. Recently, various studies have demonstrated that miRNA are involved in the regulation of Sertoli cell proliferation and adhesion. Additionally, miRNA expression could be affected by hormone, endocrine interferon, and nutrition. In this review, we summarize miRNAs related to Sertoli cell proliferation and adhesion, which will be helpful for finding and identifying more miRNAs from Sertoli cells. The review will also provide theoretical basis for the pathogenesis of infertility associated with Sertoli cells.


Subject(s)
Cell Proliferation , MicroRNAs/metabolism , Sertoli Cells/cytology , Animals , Gene Expression Regulation, Developmental , Humans , Male , MicroRNAs/genetics , Seminiferous Tubules/cytology , Seminiferous Tubules/metabolism , Sertoli Cells/metabolism , Spermatogenesis
18.
Zhongguo Zhong Yao Za Zhi ; 43(5): 964-969, 2018 Mar.
Article in Zh | MEDLINE | ID: mdl-29676095

ABSTRACT

By the means of chromatographic methods and spectroscopic evidences, 7 diterpenoids were isolated and identified from the roots of Pieris formosa. These known compounds are elucidated as secorhodomollolide C(1), pierisoid B (2), secorhodomollolide B (3), secorhodomollolide A (4), pierisformotoxin G (5), pierisformotoxin B (6) and pierisformotoxin A (7). Compounds 3, 4 were obtained from this plant for the first time. The analgesic activities of compounds 1-7 were evaluated using an acetic acidinduced writhing test in mice. Compounds 3, 4, 6, and 7 exhibited significant analgesic activity at 5 mg·kg;⁻ (ip) compared to vehicle-injected mice (P<0.05). The writhe inhibition rates of compounds 3, 4, 6 and 7 at 5 mg·kg⁻¹ (ip) were 41.3%, 39.4%, 38.6% and 37.5%, respectively.


Subject(s)
Analgesics/pharmacology , Diterpenes/pharmacology , Ericaceae/chemistry , Plant Roots/chemistry , Analgesics/isolation & purification , Animals , Diterpenes/isolation & purification , Mice , Phytochemicals/isolation & purification , Phytochemicals/pharmacology
19.
Zhonghua Nan Ke Xue ; 22(1): 72-6, 2016 Jan.
Article in Zh | MEDLINE | ID: mdl-26931031

ABSTRACT

Spermiogenesis is a complex process of differentiation and morphologic alteration, in which sperm acrosome formation is an important stage. Acrosome is an essential component of the sperm head, which develops in four distinct phases: Golgi, cap, acro- somal, and maturation, each supported by precise and orderly regulation of various genes. The regulatory genes which act on Golgi ap- paratus include GOPC, Hrb, SPATA16, PICK1, and CK2α', those involved in the cap phase are Fads2, syntaxin 2, Kdm3a, and UBR7, and participating in acrosomal and maturation phases are KIFC1, Rnf19a, and DPY19L2. The abnormalities of these genes may affect male fertility by influencing the connection of the nuclear dense lamina and acroplaxome with the nuclear membrane and then the fusion and transportation of vesicles. This review focuses on the genes involved in different phases of acrosome formation.


Subject(s)
Acrosome/physiology , Spermatids/growth & development , Spermatogenesis/genetics , Spermatozoa/growth & development , Animals , Golgi Apparatus , Male , Mice , Sperm Head/physiology
20.
Anal Chem ; 87(5): 2945-51, 2015 Mar 03.
Article in English | MEDLINE | ID: mdl-25635709

ABSTRACT

Genomic 5-methylcytosine (5-mC) modification is known to extensively regulate gene expression. The sensitive and convenient analysis of gene-specific methylation is wishful but challenging due to the lack of means that can sensitively and sequence-selectively discriminate 5-mC from cytosine without the need for polymerase chain reaction. Here we report a chemical-oxidation cleavage triggered exponential amplification reaction (EXPAR) method named COEXPAR for gene-specific methylation analysis. EXPAR was proved to not only have rapid amplification kinetics under isothermal condition but also show excellent sequence-selectivity and linear-dependence on EXPAR trigger. Further initiation of EXPAR by chemical-cleavage of DNA at 5-mC, the COEXPAR showed high specificity for methylated and nonmethylated DNA, and ∼10(7) copies of triggers were replicated in 20 min, which were used to quantify the methylation level at the methylation loci. As a result, the gene-specific methylation level of a p53 gene fragment, as a target model, was analyzed in two linear ranges of 10 fM-1 pM and 1 pM-10 nM, and limits of detection of 411 aM (S/N = 3) by fluorescence, and 576 aM (S/N = 3) by electrochemistry. The method fulfilled the assay in an isothermal way in ∼5 h without the need for tedious sample preparation and accurate thermocycling equipment, which is likely to be a facile and ultrasensitive way for gene-specific methylation analysis.


Subject(s)
DNA Cleavage , DNA Methylation , DNA/analysis , Electrochemistry , Nucleic Acid Amplification Techniques/methods , Organic Chemicals/chemistry , Base Sequence , Fluorescence , Humans , Kinetics , Limit of Detection , Mass Spectrometry , Molecular Sequence Data , Oxidation-Reduction
SELECTION OF CITATIONS
SEARCH DETAIL