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1.
Biol Reprod ; 110(4): 711-721, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38267364

RESUMO

Completion of fertilization is orchestrated by various ion channels in sperm membrane. Hyperpolarization of membrane potential, an indispensable event during the capacitation process, is dominated by sperm potassium channel (KSper). In addition to sperm-specific SLO3, which forms the channel pore, the auxiliary subunit leucine-rich-repeat-containing protein 52 (LRRC52) is required to form mKSper to function under physiological conditions. However, in human sperm, although most evidence supports that hSLO3 is the pore-forming subunit, whether hLRRC52 contributes to hKSper conductance and modulates sperm function remains to be understood. Here, using an extracellular segment that is homologous between mice and humans as an antigen, we developed a polyclonal antibody designed as LID1 that specifically detected mLRRC52 and performed co-immunoprecipitation with mSLO3. Additionally, patch-clamp recordings of mouse sperm showed that, physiological activation of mKSper and sperm functions were dramatically attenuated after treatment with LID1, indicating that LID1 functionally disrupted the regulation of mLRRC52 on mKSper. Next, LID1 was used to investigate the significance of hLRRC52 for hKSper activation. As a result, hLRRC52 was expressed in human sperm and might be assembled with hSLO3. More importantly, LID1 inhibited hKSper currents and depolarized sperm membrane potential, supporting essential modulation of hLRRC52 in hKSper. Ca2+ signaling of human sperm was also compromised in the presence of LID1, which impaired sperm motility and acrosome reaction. Because LID1 specifically inhibited both mKSper and hKSper but not mCatSper or hCatSper, our results suggest that hLRRC52 functions as an important component of hKSper and regulates sperm physiological functions.


Assuntos
Canais de Potássio Ativados por Cálcio de Condutância Alta , Motilidade dos Espermatozoides , Humanos , Masculino , Animais , Camundongos , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Sêmen/metabolismo , Espermatozoides/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
2.
Hum Reprod ; 39(4): 674-688, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38366201

RESUMO

STUDY QUESTION: Whether and how do Na+/H+ exchangers (NHEs) regulate the physiological functions of human sperm? SUMMARY ANSWER: NHE-mediated flagellar intracellular pH (pHi) homeostasis facilitates the activation of the pH-sensitive, sperm-specific Ca2+ channel (CatSper) and the sperm-specific K+ channel (KSper), which subsequently modulate sperm motility, hyperactivation, flagellar tyrosine phosphorylation, and the progesterone (P4)-induced acrosome reaction. WHAT IS KNOWN ALREADY: Sperm pHi alkalization is an essential prerequisite for the acquisition of sperm-fertilizing capacity. Different sperm functions are strictly controlled by particular pHi regulatory mechanisms. NHEs are suggested to modulate sperm H+ efflux. STUDY DESIGN, SIZE, DURATION: This was a laboratory study that used samples from >50 sperm donors over a period of 1 year. To evaluate NHE action on human sperm function, 5-(N,N-dimethyl)-amiloride (DMA), a highly selective inhibitor of NHEs, was utilized. All experiments were repeated at least five times using different individual sperm samples or cells. PARTICIPANTS/MATERIALS, SETTING, METHODS: By utilizing the pH fluorescent indicator pHrodo Red-AM, we detected alterations in single-cell pHi value in human sperm. The currents of CatSper and KSper in human sperm were recorded by the whole-cell patch-clamp technique. Changes in population and single-cell Ca2+ concentrations ([Ca2+]i) of human sperm loaded with Fluo 4-AM were measured. Membrane potential (Vm) and population pHi were quantitatively examined by a multimode plate reader after sperm were loaded with 3,3'-dipropylthiadicarbocyanine iodide and 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein, acetoxymethyl ester, respectively. Sperm motility parameters were assessed by a computer-assisted semen analysis system. Tyrosine phosphorylation was determined by immunofluorescence, and sperm acrosome reaction was evaluated by Pisum sativum agglutinin-FITC staining. MAIN RESULTS AND THE ROLE OF CHANCE: DMA-induced NHEs inhibition severely acidified the human sperm flagellar pHi from 7.20 ± 0.04 to 6.38 ± 0.12 (mean ± SEM), while the effect of DMA on acrosomal pHi was less obvious (from 5.90 ± 0.13 to 5.57 ± 0.12, mean ± SEM). The whole-cell patch-clamp recordings revealed that NHE inhibition remarkably suppressed alkalization-induced activation of CatSper and KSper. As a consequence, impairment of [Ca2+]i homeostasis and Vm maintenance were detected in the presence of DMA. During the capacitation process, pre-treatment with DMA for 2 h potently decreased sperm pHi, which in turn decreased sperm motility and kinetic parameters. Sperm capacitation-associated functions, including hyperactivation, tyrosine phosphorylation, and P4-induced acrosome reaction, were also compromised by NHE inhibition. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: This was an in vitro study. Caution should be taken when extrapolating these results to in vivo applications. WIDER IMPLICATIONS OF THE FINDINGS: This study revealed that NHEs are important physiological regulators for human CatSper and KSper, which are indispensable for human sperm fertility, suggesting that malfunction of NHEs could be an underlying mechanism for the pathogenesis of male infertility. FUNDING/COMPETING INTEREST(S): This work was supported by the National Natural Science Foundation of China (32271167 and 81871202 to X.Z.), Jiangsu Innovation and Entrepreneurship Talent Plan (JSSCRC20211543 to X.Z.), the Social Development Project of Jiangsu Province (No. BE2022765 to X.Z.), the Society and livelihood Project of Nantong City (No. MS22022087 to X.Z.), and the Natural Science Foundation of Jiangsu Province (BK20220608 to H.K.). The authors have no competing interests to declare.


Assuntos
Canais de Cálcio , Sêmen , Trocadores de Sódio-Hidrogênio , Humanos , Masculino , Equilíbrio Ácido-Base , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Sêmen/metabolismo , Motilidade dos Espermatozoides , Espermatozoides/metabolismo , Tirosina/metabolismo , Tirosina/farmacologia , Cauda do Espermatozoide/metabolismo , Cauda do Espermatozoide/fisiologia , Trocadores de Sódio-Hidrogênio/metabolismo
3.
Hum Reprod ; 39(4): 658-673, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38335261

RESUMO

STUDY QUESTION: What is the significance and mechanism of human seminal plasma extracellular vesicles (EVs) in regulating human sperm functions? SUMMARY ANSWER: EV increases the intracellular Ca2+ concentrations [Ca2+]i via extracellular Ca2+ influx by activating CatSper channels, and subsequently modulate human sperm motility, especially hyperactivated motility, which is attributed to both protein and non-protein components in EV. WHAT IS KNOWN ALREADY: EVs are functional regulators of human sperm function, and EV cargoes from normal and asthenozoospermic seminal plasma are different. Pre-fusion of EV with sperm in the acidic and non-physiological sucrose buffer solution could elevate [Ca2+]i in human sperm. CatSper, a principle Ca2+ channel in human sperm, is responsible for the [Ca2+]i regulation when sperm respond to diverse extracellular stimuli. However, the role of CatSper in EV-evoked calcium signaling and its potential physiological significance remain unclear. STUDY DESIGN, SIZE, DURATION: EV isolated from the seminal plasma of normal and asthenozoospermic semen were utilized to investigate the mechanism by which EV regulates calcium signal in human sperm, including the involvement of CatSper and the responsible cargoes in EV. In addition, the clinical application potential of EV and EV protein-derived peptides were also evaluated. This is a laboratory study that went on for more than 5 years and involved more than 200 separate experiments. PARTICIPANTS/MATERIALS, SETTING, METHODS: Semen donors were recruited in accordance with the Institutional Ethics Committee on human subjects of the Affiliated Hospital of Nantong University and Jiangxi Maternal and Child Health Hospital. The Flow NanoAnalyzer, western blotting, and transmission electron microscope were used to systematically characterize seminal plasma EV. Sperm [Ca2+]i responses were examined by fluorimetric measurement. The whole-cell patch-clamp technique was performed to record CatSper currents. Sperm motility parameters were assessed by computer-assisted sperm analysis. Sperm hyperactivation was also evaluated by examining their penetration ability in viscous methylcellulose media. Protein and non-protein components in EV were analyzed by liquid chromatography-mass spectrum. The levels of prostaglandins, reactive oxygen species, malonaldehyde, and DNA integrity were detected by commercial kits. MAIN RESULTS AND THE ROLE OF CHANCE: EV increased [Ca2+]i via an extracellular Ca2+ influx, which could be suppressed by a CatSper inhibitor. Also, EV potentiated CatSper currents in human sperm. Furthermore, the EV-in [Ca2+]i increase and CatSper currents were absent in a CatSper-deficient sperm, confirming the crucial role of CatSper in EV induced Ca2+ signaling in human sperm. Both proteins and non-protein components of EV contributed to the increase of [Ca2+]i, which were important for the effects of EV on human sperm. Consequently, EV and its cargos promoted sperm hyperactivated motility. In addition, seminal plasma EV protein-derived peptides, such as NAT1-derived peptide (N-P) and THBS-1-derived peptide (T-P), could activate the sperm calcium signal and enhance sperm function. Interestingly, EV derived from asthenozoospermic semen caused a lower increase of [Ca2+]i than that isolated from normal seminal plasma (N-EV), and N-EV significantly improved sperm motility and function in both asthenozoospermic samples and frozen-thawed sperm. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: This was an in vitro study and caution must be taken when extrapolating the physiological relevance to in vivo regulation of sperm. WIDER IMPLICATIONS OF THE FINDINGS: Our findings demonstrate that the CatSper-mediated-Ca2+ signaling is involved in EV-modulated sperm function under near physiological conditions, and EV and their derivates are a novel CatSper and sperm function regulators with potential for clinical application. They may be developed to improve sperm motility resulting from low [Ca2+]i response and/or freezing and thawing. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by the National Natural Science Foundation of China (32271167), the Social Development Project of Jiangsu Province (BE2022765), the Nantong Social and People's Livelihood Science and Technology Plan (MS22022087), the Basic Science Research Program of Nantong (JC22022086), and the Jiangsu Innovation and Entrepreneurship Talent Plan (JSSCRC2021543). The authors declare no conflict of interest.


Assuntos
Astenozoospermia , Canais de Cálcio , Vesículas Extracelulares , Sêmen , Motilidade dos Espermatozoides , Humanos , Masculino , Astenozoospermia/metabolismo , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Peptídeos/metabolismo , Peptídeos/farmacologia , Sêmen/química , Sêmen/metabolismo , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo , Vesículas Extracelulares/química , Vesículas Extracelulares/metabolismo
4.
Planta Med ; 88(11): 881-890, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34359084

RESUMO

The root Rhynchosia volubilis was widely used for contraception in folk medicine, although its molecular mechanism on antifertility has not yet been revealed. In human sperm, it was reported that the cation channel of sperm, an indispensable cation channel for the fertilization process, could be regulated by various steroid-like compounds in plants. Interestingly, these nonphysiological ligands would also disturb the activation of the cation channel of sperm induced by progesterone. Therefore, this study aimed to explore whether the compounds in R. volubilis affect the physiological regulation of the cation channel of sperm. The bioguided isolation of the whole herb of R. volubilis has resulted in the novel discovery of five new prenylated isoflavonoids, rhynchones A - E (1:  - 5: ), a new natural product, 5'-O-methylphaseolinisoflavan (6: ) (1H and 13C NMR data, Supporting Information), together with twelve known compounds (7:  - 18: ). Their structures were established by extensive spectroscopic analyses and drawing a comparison with literature data, while their absolute configurations were determined by electronic circular dichroism calculations. The experiments of intracellular Ca2+ signals and patch clamping recordings showed that rhynchone A (1: ) significantly reduced cation channel of sperm activation by competing with progesterone. In conclusion, our findings indicat that rhynchone A might act as a contraceptive compound by impairing the activation of the cation channel of sperm and thus prevent fertilization.


Assuntos
Progesterona , Motilidade dos Espermatozoides , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Humanos , Masculino , Progesterona/análise , Progesterona/metabolismo , Progesterona/farmacologia , Sementes , Espermatozoides/química , Espermatozoides/metabolismo
5.
Ecotoxicol Environ Saf ; 221: 112418, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34146982

RESUMO

BACKGROUND: Bisphenol A (BPA), a widely used plastic monomer and plasticizer, is detectable in blood, urine and semen of a healthy people, with concentrations ranging from 0.1 nM to 10 nM. It has been shown that in vitro exposure of BPA as low as 0.001 nM could significantly inhibited mouse sperm motility and acrosome reaction. However, it is still unclear whether BPA at those physiologically detectable concentration affects human sperm. METHODS: The effects of different concentrations of BPA (0, 10-3, 10-2, 10-1, 10, 103 nM) on sperm functions were examined, including human sperm viability, kinematic parameters, hyperactivation and capacitation. RESULTS: BPA caused a remarkable decline in human sperm viability, motility and progressive motility, hyperactivation, capacitation and progesterone-induced acrosome reaction. Mechanism studies showed that BPA could suppress the protein tyrosine phosphorylation level of human sperm, but had no effect on sperm calcium signaling. CONCLUSIONS: Physiologically detectable concentrations of BPA may impair human sperm functions via suppressing protein tyrosine phosphorylation of human sperm, implying that environmental pollution of BPA might be a factor contributing to male infertility.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Fenóis/toxicidade , Plastificantes/toxicidade , Espermatozoides/efeitos dos fármacos , Reação Acrossômica/efeitos dos fármacos , Humanos , Masculino , Fosforilação/efeitos dos fármacos , Progesterona/metabolismo , Proteínas/metabolismo , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Tirosina/metabolismo
6.
Int J Mol Sci ; 22(4)2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33562644

RESUMO

Sperm-specific K+ ion channel (KSper) and Ca2+ ion channel (CatSper), whose elimination causes male infertility in mice, determine the membrane potential and Ca2+ influx, respectively. KSper and CatSper can be activated by cytosolic alkalization, which occurs during sperm going through the alkaline environment of the female reproductive tract. However, which intracellular pH (pHi) regulator functionally couples to the activation of KSper/CatSper remains obscure. Although Na+/H+ exchangers (NHEs) have been implicated to mediate pHi in sperm, there is a lack of direct evidence confirming the functional coupling between NHEs and KSper/CatSper. Here, 5-(N, N-dimethyl)-amiloride (DMA), an NHEs inhibitor that firstly proved not to affect KSper/CatSper directly, was chosen to examine NHEs function on KSper/CatSper in mouse sperm. The results of patch clamping recordings showed that, when extracellular pH was at the physiological level of 7.4, DMA application caused KSper inhibition and the depolarization of membrane potential when pipette solutions were not pH-buffered. In contrast, these effects were minimized when pipette solutions were pH-buffered, indicating that they solely resulted from pHi acidification caused by NHEs inhibition. Similarly, DMA treatment reduced CatSper current and intracellular Ca2+, effects also dependent on the buffer capacity of pH in pipette solutions. The impairment of sperm motility was also observed after DMA incubation. These results manifested that NHEs activity is coupled to the activation of KSper/CatSper under physiological conditions.


Assuntos
Amilorida/análogos & derivados , Canais de Cálcio/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Espermatozoides/fisiologia , Amilorida/farmacologia , Animais , Cálcio/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Infertilidade Masculina/metabolismo , Masculino , Potenciais da Membrana , Camundongos , Técnicas de Patch-Clamp , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos
7.
Phys Rev Lett ; 122(4): 045302, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30768308

RESUMO

Recently, exciton polaritons in a semiconductor microcavity were found to condense into a coherent ground state much like a Bose-Einstein condensate and a superfluid. They have become a unique testbed for generating and manipulating quantum vortices in a driven-dissipative superfluid. Here, we generate an exciton-polariton condensate with a nonresonant Laguerre-Gaussian optical beam and verify the direct transfer of light's orbital angular momentum to an exciton-polariton quantum fluid. Quantized vortices are found in spite of the large energy relaxation involved in nonresonant pumping. We identified phase singularity, density distribution, and energy eigenstates for the vortex states. Our observations confirm that nonresonant optical Laguerre-Gaussian beam can be used to manipulate chirality, topological charge, and stability of the nonequilibrium quantum fluid. These vortices are quite robust, only sensitive to the orbital angular momentum of light and not other parameters such as energy, intensity, size, or shape of the pump beam. Therefore, optical information can be transferred between the photon and exciton-polariton with ease and the technique is potentially useful to form the controllable network of multiple topological charges even in the presence of spectral randomness in a solid state system.

8.
Sensors (Basel) ; 18(3)2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29547551

RESUMO

In object detection systems for autonomous driving, LIDAR sensors provide very useful information. However, problems occur because the object representation is greatly distorted by changes in distance. To solve this problem, we propose a LIDAR shape set that reconstructs the shape surrounding the object more clearly by using the LIDAR point information projected on the object. The LIDAR shape set restores object shape edges from a bird's eye view by filtering LIDAR points projected on a 2D pixel-based front view. In this study, we use this shape set for two purposes. The first is to supplement the shape set with a LIDAR Feature map, and the second is to divide the entire shape set according to the gradient of the depth and density to create a 2D and 3D bounding box proposal for each object. We present a multimodal fusion framework that classifies objects and restores the 3D pose of each object using enhanced feature maps and shape-based proposals. The network structure consists of a VGG -based object classifier that receives multiple inputs and a LIDAR-based Region Proposal Networks (RPN) that identifies object poses. It works in a very intuitive and efficient manner and can be extended to other classes other than vehicles. Our research has outperformed object classification accuracy (Average Precision, AP) and 3D pose restoration accuracy (3D bounding box recall rate) based on the latest studies conducted with KITTI data sets.

9.
Sensors (Basel) ; 17(1)2017 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-28117742

RESUMO

To understand driving environments effectively, it is important to achieve accurate detection and classification of objects detected by sensor-based intelligent vehicle systems, which are significantly important tasks. Object detection is performed for the localization of objects, whereas object classification recognizes object classes from detected object regions. For accurate object detection and classification, fusing multiple sensor information into a key component of the representation and perception processes is necessary. In this paper, we propose a new object-detection and classification method using decision-level fusion. We fuse the classification outputs from independent unary classifiers, such as 3D point clouds and image data using a convolutional neural network (CNN). The unary classifiers for the two sensors are the CNN with five layers, which use more than two pre-trained convolutional layers to consider local to global features as data representation. To represent data using convolutional layers, we apply region of interest (ROI) pooling to the outputs of each layer on the object candidate regions generated using object proposal generation to realize color flattening and semantic grouping for charge-coupled device and Light Detection And Ranging (LiDAR) sensors. We evaluate our proposed method on a KITTI benchmark dataset to detect and classify three object classes: cars, pedestrians and cyclists. The evaluation results show that the proposed method achieves better performance than the previous methods. Our proposed method extracted approximately 500 proposals on a 1226 × 370 image, whereas the original selective search method extracted approximately 10 6 × n proposals. We obtained classification performance with 77.72% mean average precision over the entirety of the classes in the moderate detection level of the KITTI benchmark dataset.

10.
Sensors (Basel) ; 17(4)2017 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-28420194

RESUMO

Multiple-object tracking is affected by various sources of distortion, such as occlusion, illumination variations and motion changes. Overcoming these distortions by tracking on RGB frames, such as shifting, has limitations because of material distortions caused by RGB frames. To overcome these distortions, we propose a multiple-object fusion tracker (MOFT), which uses a combination of 3D point clouds and corresponding RGB frames. The MOFT uses a matching function initialized on large-scale external sequences to determine which candidates in the current frame match with the target object in the previous frame. After conducting tracking on a few frames, the initialized matching function is fine-tuned according to the appearance models of target objects. The fine-tuning process of the matching function is constructed as a structured form with diverse matching function branches. In general multiple object tracking situations, scale variations for a scene occur depending on the distance between the target objects and the sensors. If the target objects in various scales are equally represented with the same strategy, information losses will occur for any representation of the target objects. In this paper, the output map of the convolutional layer obtained from a pre-trained convolutional neural network is used to adaptively represent instances without information loss. In addition, MOFT fuses the tracking results obtained from each modality at the decision level to compensate the tracking failures of each modality using basic belief assignment, rather than fusing modalities by selectively using the features of each modality. Experimental results indicate that the proposed tracker provides state-of-the-art performance considering multiple objects tracking (MOT) and KITTIbenchmarks.

11.
Nano Lett ; 15(9): 5875-82, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26226506

RESUMO

We report a novel negative photoconductivity (NPC) mechanism in n-type indium arsenide nanowires (NWs). Photoexcitation significantly suppresses the conductivity with a gain up to 10(5). The origin of NPC is attributed to the depletion of conduction channels by light assisted hot electron trapping, supported by gate voltage threshold shift and wavelength-dependent photoconductance measurements. Scanning photocurrent microscopy excludes the possibility that NPC originates from the NW/metal contacts and reveals a competing positive photoconductivity. The conductivity recovery after illumination substantially slows down at low temperature, indicating a thermally activated detrapping mechanism. At 78 K, the spontaneous recovery of the conductance is completely quenched, resulting in a reversible memory device, which can be switched by light and gate voltage pulses. The novel NPC based optoelectronics may find exciting applications in photodetection and nonvolatile memory with low power consumption.

12.
Theor Appl Genet ; 125(5): 1033-46, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22751999

RESUMO

Rice stripe disease, caused by rice stripe virus (RSV) is a serious constraint to rice production in subtropical regions of East Asia. We performed fine mapping of a RSV resistance QTL on chromosome 11, qSTV11 ( SG ), using near-isogenic lines (NILs, BC(6)F(4)) derived from a cross between the highly resistant variety, Shingwang, and the highly susceptible variety, Ilpum, using 11 insertion and deletion (InDel) markers. qSTV11 ( SG ) was localized to a 150-kb region between InDel 11 (17.86 Mbp) and InDel 5 (18.01 Mbp). Among the two markers in this region, InDel 7 is diagnostic of RSV resistance in 55 Korean japonica and indica rice varieties. InDel 7 could also distinguish the allele type of Nagdong, Shingwang, Mudgo, and Pe-bi-hun from Zenith harboring the Stv-b ( i ) allele. As a result, qSTV11 ( SG ) is likely to be the Stv-b ( i ) allele. There were 21 genes in the 150-kb region harboring the qSTV11 ( SG ) locus. Three of these genes, LOC_Os11g31430, LOC_Os11g31450, and LOC_Os11g31470, were exclusively expressed in the susceptible variety. These expression profiles were consistent with the quantitative nature along with incomplete dominance of RSV resistance. Sequencing of these genes showed that there were several amino acid substitutions between susceptible and resistant varieties. Putative functions of these candidate genes for qSTV11 (SG) are discussed.


Assuntos
Mapeamento Cromossômico , Genes de Plantas/genética , Imunidade Inata/genética , Oryza/genética , Oryza/virologia , Doenças das Plantas/genética , Locos de Características Quantitativas/genética , Tenuivirus/patogenicidade , Cromossomos de Plantas/genética , DNA de Plantas/genética , Ligação Genética , Marcadores Genéticos , Genótipo , Oryza/imunologia , Fenótipo , Doenças das Plantas/imunologia , Doenças das Plantas/virologia , Reação em Cadeia da Polimerase , Tenuivirus/genética , Tenuivirus/imunologia
13.
J Nat Prod ; 75(10): 1706-11, 2012 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-23031087

RESUMO

The in vitro effects on melanogenesis of γ-oryzanol (1), a rice bran-derived phytosterol, were investigated. The melanin content in B16F1 cells was significantly and dose-dependently reduced (-13% and -28% at 3 and 30 µM, respectively). Tyrosinase enzyme activity was inhibited by 1 both in a cell-free assay and when analyzed based on the measurement of cellular tyrosinase activity. Transcriptome analysis was performed to investigate the biological pathways altered by 1, and it was found that gene expression involving protein kinase A (PKA) signaling was markedly altered. Subsequent analyses revealed that 1 stimulation in B16 cells reduced cytosolic cAMP concentrations, PKA activity (-13% for cAMP levels and -40% for PKA activity), and phosphorylation of the cAMP-response element binding protein (-57%), which, in turn, downregulated the expression of microphthalmia-associated transcription factor (MITF; -59% for mRNA and -64% for protein), a key melanogenic gene transcription factor. Accordingly, tyrosinase-related protein 1 (TRP-1; -69% for mRNA and -82% for protein) and dopachrome tautomerase (-51% for mRNA and -92% for protein) in 1-stimulated B16F1 cells were also downregulated. These results suggest that 1 has dual inhibitory activities for cellular melanogenesis by inhibiting tyrosinase enzyme activity and reducing MITF and target genes in the PKA-dependent pathway.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Melaninas/genética , Monofenol Mono-Oxigenase/metabolismo , Oryza/química , Fenilpropionatos/farmacologia , AMP Cíclico/análise , Oxirredutases Intramoleculares/genética , Melaninas/metabolismo , Estrutura Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Oryza/genética , Fenilpropionatos/química
14.
J Sci Food Agric ; 92(7): 1462-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22144043

RESUMO

BACKGROUND: It is difficult to predict rice bread quality only from the amylose content (AC) or dough characteristics of new lines produced by rice breeding programmes. This study investigated the AC relative to bread baking quality of rice varieties developed in Korea, and identified specific characteristics that contribute to rice bread quality. RESULTS: Manmibyeo, Jinsumi, Seolgaeng and Hanareumbyeo were classified as low AC, YR24088 Acp9, Suweon517, Chenmaai and Goamibyeo as intermediate AC and Milyang261 as high AC. Suweon517, Milyang261 and Manmibyeo had a high water absorption index (WAI), while Goamibyeo, YR24088 Acp9, Jinsumi, Seolgaeng, Hanareumbyeo and Chenmaai had a low WAI. The gelatinisation enthalpy of flour varied from 9.2 J g(-1) in Milyang261 to 14.8 J g(-1) in YR24088 Acp9. After 7 days of storage the rate of flour retrogradation and crumb firmness were weakly correlated, with the exception of Jinsumi. Bread volumes of Jinsumi, Chenmaai, YR24088 Acp9 and Goamibyeo were comparable to that of wheat flour, but the rest were unsuited to bread making because of their low volume and hard crumb texture. CONCLUSION: Based on volume, texture and crumb firmness ratio, Chenmaai and Goamibyeo were the most appropriate varieties for making bread. An intermediate AC and low WAI were the primary indicators of rice bread flour quality.


Assuntos
Amilose/análise , Pão/análise , Dieta , Oryza , Sementes , Absorção , Pão/normas , Farinha , Tecnologia de Alimentos , Géis , Humanos , Oryza/classificação , República da Coreia , Especificidade da Espécie , Água
15.
Orthop J Sports Med ; 10(5): 23259671221089250, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35592017

RESUMO

Background: Anatomic placement of the meniscal allograft is imperative to achieve satisfactory outcomes after meniscal allograft transplantation (MAT). Few studies have reported on the accuracy of the provisional location of the center of the anterior horn of the lateral meniscus (AHLM). Hypothesis: The authors hypothesized that the provisional center would not coincide with the anatomic center of the AHLM. Study Design: Descriptive laboratory study. Methods: Tibial plateaus were retrieved from 93 consecutive patients who underwent total knee arthroplasty. A complete radial cut was made 2 cm lateral to the insertion of the AHLM on the retrieved tibial plateau. While moving the stump of the anterior horn with forceps, the center of the insertion was determined, and a Kirschner wire (provisional wire) was drilled into the location. The insertion area of the AHLM was dissected carefully, and the periphery of the insertion area of the anterior horn was marked. Another Kirschner wire (anatomic wire) was drilled into the center of the dissected anterior horn. The resected tibial plateau was positioned so that the longitudinal line of the tibial plateau was aligned on a plastic ruler. The distance between the provisional and anatomic wires was measured by a digital caliper along the longitudinal and vertical axes. Results: The mean distance between the provisional and anatomic wires was 2.5 ± 1.2 mm. The provisional wire in 14 patients (15%) was placed at the anatomic center. In 36 patients (39%), the provisional wire was drilled anterolateral to the anatomic center, and in 18 patients (19%), the wire was drilled anteromedial to the anatomic center. In 21 patients (23%), the provisional wire was located within 2 mm of the anatomic center, and in 62 patients (67%), the wire was located within 3 mm of the anatomic center. Conclusion: The provisional wire was located a mean of 2.5 mm from the anatomic center, and only 23% of patients had wires that were located within 2 mm of the anatomic center. In 39% of patients, the provisional wire was drilled anterolateral to the anatomic center. This finding needs to be considered during lateral MAT. Clinical Relevance: Without dissection of the AHLM, the determination of the anatomic center of the anterior horn is not accurate during lateral MAT.

16.
Cell Rep Med ; 3(12): 100825, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36513070

RESUMO

Sperm chemotaxis is required for guiding sperm toward the egg. However, the molecular identity of physiological chemoattractant and its involvement in infertility remain elusive. Here, we identify DEFB19/119 (mouse/human orthologs) as a physiological sperm chemoattractant. The epithelia of the female reproductive tract and the cumulus-oocyte complex secrete DEFB19/119 that elicits calcium mobilization via the CatSper channel and induces sperm chemotaxis in capacitated sperm. Manipulating the level of DEFB19 in mice determines the number of sperm arriving at the fertilization site. Importantly, we identify exon mutations in the DEFB119 gene in idiopathic infertile women with low level of DEFB119 in the follicular fluid. The level of DEFB119 correlates with the chemotactic potency of follicular fluid and predicts the infertile outcome with positive correlation. This study reveals the pivotal role of DEFB19/119 in sperm chemotaxis and demonstrates its potential application in the diagnosis of idiopathic infertility.


Assuntos
Infertilidade Feminina , beta-Defensinas , Humanos , Masculino , Feminino , Animais , Camundongos , Quimiotaxia/fisiologia , Sêmen/metabolismo , Espermatozoides/metabolismo , Fatores Quimiotáticos/metabolismo
17.
Orthop J Sports Med ; 9(9): 23259671211042334, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34541018

RESUMO

BACKGROUND: Biomechanical studies have demonstrated significant loosening of the adjustable-loop device as compared with the fixed-loop device used in anterior cruciate ligament reconstruction. Retensioning of the adjustable loop has been recommended; however, the timing of the retensioning is unknown. HYPOTHESIS: Early (ER) and late retensioning (LR) will show similar gapping between the femoral tunnel and graft on follow-up magnetic resonance imaging (MRI) and similar clinical outcomes. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: This study included 101 patients who underwent hamstring anterior cruciate ligament reconstruction using the adjustable-loop device for femoral fixation between June 2016 and January 2018. All patients a had follow-up MRI on postoperative day 1. Patients with revision surgery and those with reinjury after reconstruction were excluded. In the ER group, retensioning and knot tying of the initially tightened adjustable loop were performed after the flip of the button and before the graft was fixed at the tibia. In the LR group, retensioning and knot tying were performed after initial tightening of the adjustable loop and graft fixation at the tibial side. The tunnel-graft gap measured on multiplanar reformatted images of MRI scans was compared between the groups, as were clinical outcomes. RESULTS: The mean age of the patients at the time of surgery was 30.3 years (range, 14-61 years). ER and knot tying were performed in 56 patients and LR and knot tying in 45. Preoperative characteristics of the 2 groups showed no significant differences. The mean ± SD tunnel-graft gap was 1.5 ± 2.0 mm in the ER group and 5.4 ± 4.0 mm in the LR group (P < .001). There were no significant differences in clinical outcomes between the groups. CONCLUSION: ER and knot tying demonstrated less tunnel-graft gap than that of LR. However, there were no differences in clinical outcomes according to the timing of retensioning.

18.
Sci Rep ; 11(1): 7699, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33833327

RESUMO

We report the growth mechanism and optical characteristics of type-II band-aligned GaSb quantum dots (QDs) grown on GaAs using a droplet epitaxy-driven nanowire formation mechanism with molecular beam epitaxy. Using transmission electron microscopy and scanning electron microscopy images, we confirmed that the QDs, which comprised zinc-blende crystal structures with hexagonal shapes, were successfully grown through the formation of a nanowire from a Ga droplet, with reduced strain between GaAs and GaSb. Photoluminescence (PL) peaks of GaSb capped by a GaAs layer were observed at 1.11 eV, 1.26 eV, and 1.47 eV, assigned to the QDs, a wetting-like layer (WLL), and bulk GaAs, respectively, at the measurement temperature of 14 K and excitation laser power of 30 mW. The integrated PL intensity of the QDs was significantly stronger than that of the WLL, which indicated well-grown GaSb QDs on GaAs and the generation of an interlayer exciton, as shown in the power- and temperature-dependent PL spectra, respectively. In addition, time-resolved PL data showed that the GaSb QD and GaAs layers formed a self-aligned type-II band alignment; the temperature-dependent PL data exhibited a high equivalent internal quantum efficiency of 15 ± 0.2%.

19.
Reprod Toxicol ; 93: 99-105, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32004625

RESUMO

Anethole is a natural anisole derivative that has been widely used in food and daily chemical industries, agricultural applications and the traditional medicine. It is closely related to aspects of daily life, and humans can easily be exposed to it. Although the reproductive toxicity of anethole was shown in the rat, its effect on human reproduction remains unknown. In this study, we examined the effect of anethole on human sperm in vitro. Different anethole doses (0.1, 1, 10, and 100 µM) were applied to ejaculated human sperm. Fertilization-essential functions, as well as the intracellular calcium concentration ([Ca2+]i) and tyrosine phosphorylation, two vital factors for regulating sperm function, were measured. The results indicated that 10 and 100 µM anethole significantly reduced the motility, hyperactivation, and penetration ability of human sperm (P < 0.05) and inhibited the increase in human sperm functions induced by progesterone, a hormone essential for sperm function activation. Additionally, 10 and 100 µM anethole decreased both basal and progesterone-increased tyrosine phosphorylation, [Ca2+]i, and the current of CATSPER, a cation channel of sperm predominant for Ca2+ influx. These results suggest that anethole inhibits human sperm functions by reducing sperm [Ca2+]i through CATSPER and suppressing tyrosine phosphorylation in vitro, raising the fact that the caution is needed when overtaking anethole.


Assuntos
Anisóis/toxicidade , Cálcio/metabolismo , Espermatozoides/efeitos dos fármacos , Tirosina/metabolismo , Adulto , Derivados de Alilbenzenos , Humanos , Masculino , Fosforilação/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Espermatozoides/fisiologia , Adulto Jovem
20.
Chemosphere ; 259: 127493, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32622245

RESUMO

Pentachlorophenol (PCP), a highly toxic contaminant of chlorophenols, is common in a variety of environments and presents serious risks to animal and human health. However, the reproductive toxicity and potential actions of PCP have not been investigated thoroughly, especially in humans. Here, human spermatozoa were used to evaluate the effect of PCP on cell function and to explore the underlying mechanisms. PCP had no substantive effects on sperm viability or motility, nor on the ability to penetrate viscous medium, sperm hyperactivation or spontaneous acrosome reactions. However, PCP significantly inhibited these properties induced by progesterone (P4). Consistent with the functional observations, although PCP itself did not affect the basal intracellular Ca2+ concentrations and CatSper current, PCP dose-dependently inhibited increases of intracellular Ca2+ concentrations caused by P4. In addition, the activation of CatSper induced by P4 was largely suppressed by PCP. This is the first report showing that PCP may serves as an antagonist of the P4 membrane receptor to interfere with Ca2+ signaling by compromising the action of P4 on regulating sperm function. These findings suggest that the reproductive toxicity of PCP should also be a matter of concern as a mammalian health risk.


Assuntos
Pentaclorofenol/farmacologia , Progesterona/farmacologia , Espermatozoides/efeitos dos fármacos , Reação Acrossômica/efeitos dos fármacos , Animais , Cálcio/metabolismo , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/metabolismo , Canais de Cálcio/farmacologia , Humanos , Masculino , Pentaclorofenol/metabolismo , Reprodução , Análise do Sêmen , Motilidade dos Espermatozoides/efeitos dos fármacos , Viscosidade
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