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1.
Nature ; 595(7868): 521-525, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34290425

RESUMEN

Whereas ferromagnets have been known and used for millennia, antiferromagnets were only discovered in the 1930s1. At large scale, because of the absence of global magnetization, antiferromagnets may seem to behave like any non-magnetic material. At the microscopic level, however, the opposite alignment of spins forms a rich internal structure. In topological antiferromagnets, this internal structure leads to the possibility that the property known as the Berry phase can acquire distinct spatial textures2,3. Here we study this possibility in an antiferromagnetic axion insulator-even-layered, two-dimensional MnBi2Te4-in which spatial degrees of freedom correspond to different layers. We observe a type of Hall effect-the layer Hall effect-in which electrons from the top and bottom layers spontaneously deflect in opposite directions. Specifically, under zero electric field, even-layered MnBi2Te4 shows no anomalous Hall effect. However, applying an electric field leads to the emergence of a large, layer-polarized anomalous Hall effect of about 0.5e2/h (where e is the electron charge and h is Planck's constant). This layer Hall effect uncovers an unusual layer-locked Berry curvature, which serves to characterize the axion insulator state. Moreover, we find that the layer-locked Berry curvature can be manipulated by the axion field formed from the dot product of the electric and magnetic field vectors. Our results offer new pathways to detect and manipulate the internal spatial structure of fully compensated topological antiferromagnets4-9. The layer-locked Berry curvature represents a first step towards spatial engineering of the Berry phase through effects such as layer-specific moiré potential.

2.
J Am Chem Soc ; 146(5): 3396-3404, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38266485

RESUMEN

Covalent organic frameworks (COFs), with the features of flexible structure regulation and easy introduction of functional groups, have aroused broad interest in the field of photocatalysis. However, due to the low light absorption intensity, low photoelectron conversion efficiency, and lack of suitable active sites, it remains a great challenge to achieve efficient photocatalytic aerobic oxidation reactions. Herein, based on reticular chemistry, we rationally designed a series of three-motif molecular junction type COFs, which formed dual photosensitizer coupled redox molecular junctions containing multifunctional COF photocatalysts. Significantly, due to the strong light adsorption ability of dual photosensitizer units and integrated oxidation and reduction features, the PY-BT COF exhibited the highest activity for photocatalytic aerobic oxidation. Especially, it achieved a photocatalytic benzylamine conversion efficiency of 99.9% in 2.5 h, which is much higher than that of the two-motif molecular junctions with only one photosensitizer or redox unit lacking COFs. The mechanism of selective aerobic oxidation was studied through comprehensive experiments and density functional theory calculations. The results showed that the photoinduced electron transfer occurred from PY and then through triphenylamine to BT. Furthermore, the thermodynamics energy for benzylamine oxidation on PY-BT COF was much lower than that for others, which confirmed the synergistic effect of dual photosensitizer coupled redox molecular junction COFs. This work provided a new strategy for the design of functional COFs with three-motif molecular junctions and also represented a new insight into the multifunctional COFs for organic catalytic reactions.

3.
J Am Chem Soc ; 146(37): 25832-25840, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39231362

RESUMEN

The connectivity (valency) of building blocks for constructing 3D covalent organic frameworks (COFs) has long been limited to 4, 6, 8, and 12. Developing a higher connectivity remains a great challenge in the field of COF structural design. Herein, this work reports a hierarchical expansion strategy for making 16-connected building blocks to construct 3D COFs with sqc topology. The [16 + 2] construction achieved by condensation between a 16-connected carbazolyl dicyanobenzene-based building block (CzTPN) and linear diamino linkers (BD or Bpy) affords two 3D COFs (named CzBD COF and CzBpy COF). Furthermore, attributed to the well-organized donor-acceptor (D-A) heterojunction, the Ni chelated CzBpy COF (Ni@CzBpy COF) exhibits excellent performance for photoredox/Ni dual catalytic C(sp3)-C(sp2) cross-coupling of alkyltrifluoroborates with aryl halides, achieving a maximum 98% conversion and 94% yield for various substrates. This work developed the first case of high-connectivity COFs bearing 16-connected units, which is the highest connectivity reported until now, and achieved efficient photocatalysis applications, thus greatly enriching the possibilities of COFs.

4.
Nat Mater ; 22(5): 583-590, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36894774

RESUMEN

Using circularly polarized light to control quantum matter is a highly intriguing topic in physics, chemistry and biology. Previous studies have demonstrated helicity-dependent optical control of chirality and magnetization, with important implications in asymmetric synthesis in chemistry; homochirality in biomolecules; and ferromagnetic spintronics. We report the surprising observation of helicity-dependent optical control of fully compensated antiferromagnetic order in two-dimensional even-layered MnBi2Te4, a topological axion insulator with neither chirality nor magnetization. To understand this control, we study an antiferromagnetic circular dichroism, which appears only in reflection but is absent in transmission. We show that the optical control and circular dichroism both arise from the optical axion electrodynamics. Our axion induction provides the possibility to optically control a family of [Formula: see text]-symmetric antiferromagnets ([Formula: see text], inversion; [Formula: see text], time-reversal) such as Cr2O3, even-layered CrI3 and possibly the pseudo-gap state in cuprates. In MnBi2Te4, this further opens the door for optical writing of a dissipationless circuit formed by topological edge states.

5.
Proc Natl Acad Sci U S A ; 117(27): 15517-15523, 2020 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-32554603

RESUMEN

Topological electrons in semimetals are usually vulnerable to chemical doping and environment change, which restricts their potential application in future electronic devices. In this paper, we report that the type-II Dirac semimetal [Formula: see text] hosts exceptional, robust topological electrons which can tolerate extreme change of chemical composition. The Dirac electrons remain intact, even after a substantial part of V atoms have been replaced in the [Formula: see text] solid solutions. This Dirac semimetal state ends at [Formula: see text], where a Lifshitz transition to p-type trivial metal occurs. The V-Al bond is completely broken in this transition as long as the bonding orbitals are fully depopulated by the holes donated from Ti substitution. In other words, the Dirac electrons in [Formula: see text] are protected by the V-Al bond, whose molecular orbital is their bonding gravity center. Our understanding on the interrelations among electron count, chemical bond, and electronic properties in topological semimetals suggests a rational approach to search robust, chemical-bond-protected topological materials.

6.
Psychiatry Clin Neurosci ; 77(10): 541-549, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37350640

RESUMEN

AIMS: Hikikomori is a common phenomenon reported in Japan and many other countries. However, the broad trends of the research publications on hikikomori are unclear. Therefore, this study examined the patterns of research on hikikomori using bibliometric analysis. METHODS: Relevant publications were searched in Web of Science. Bibliometric analyses were performed with CiteSpace, R and VOSviewer. RESULTS: In total, 297 publications on hikikomori met the eligibility criteria. The International Journal of Social Psychiatry (IF = 10.461) published the most papers (K = 17, or 5.7%) on hikikomori. Takahiro A. Kato from Kyushu University (41; 13.8%; H-index = 18) was the most influential author, while Takahiro A. Kato (total link strength [TLS]: 235), Alan R. Teo (TLS: 157), and Masaru Tateno (TLS: 153) separately had the strongest research collaboration with other researchers. Of all countries that published on hikikomori, Japan had the highest number of publications (K = 91). The keywords "United States" and "psychiatric diagnosis" received the most attention between 2013 and 2015, whereas "health" and "autism spectrum disorder" received the most attention in 2021 and 2022. CONCLUSIONS: Peer-reviewed research publications on hikikomori are growing rapidly and the research trends in this field are also changing.


Asunto(s)
Trastorno del Espectro Autista , Fobia Social , Humanos , Bibliometría , Japón
7.
J Asian Nat Prod Res ; 25(1): 1-10, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35023415

RESUMEN

Five new compounds, named gingerol A (1a and 1b), gingerol B (2), diphenylheptane glycoside A (3) and diphenylheptane glycoside B (4), were isolated from the acetone extract of Zingiberis Rhizoma Recens. The structures of new compounds were elucidated on the basis of spectroscopic methods including UV, IR, 1D NMR, 2D NMR and HR-ESI-MS. Compounds 2-4 could significantly decrease the apoptosis rate and increase the survival rate of human normal lung epithelial cells (BEAS-2B) at the concentration of 10 µM.


Asunto(s)
Catecoles , Extractos Vegetales , Humanos , Glicósidos
8.
Angew Chem Int Ed Engl ; 62(44): e202311999, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37709724

RESUMEN

The high local electron density and efficient charge carrier separation are two important factors to affect photocatalytic activity, especially for the CO2 photoreduction reaction. However, the systematic studies on the structure-functional relationship regarding the above two factors based on precisely structure model are rarely reported. Herein, as a proof-of-concept, we developed a new strategy on the evaluation of local electron density by controlling the relative electron-deficient (ED) and electron-rich (ER) intensity of monomer at a molecular level based on three rational-designed vinylene-linked sp2 carbon-covalent organic frameworks (COFs). As expected, the as-prepared vinylene-linked sp2 carbon-conjugated metal-covalent organic framework (MCOFs) (VL-MCOF-1) with molecular junction exhibited excellent activities for CO2 -to-HCOOH conversion (283.41 µmol g-1 h-1 ) and high selectivity of 97.1 %, much higher than the VL-MCOF-2 and g-C34 N6 -COF, which is due to the synergistic effect of the multi-electronic metal clusters (Cu3 (PyCA)3 ) (PyCA=pyrazolate-4-carboxaldehyde) as strong ER roles and cyanopyridine units as ED roles and active sites, as well as the boosted photo-induced charge separation efficiency of vinyl connection and increased light utilization ability. These results not only provide a strategy for regulating the electron-density distribution of photocatalysts at the molecular level but also offers profound insights for metal clusters-based COFs to effective CO2 conversion.

9.
Angew Chem Int Ed Engl ; 62(31): e202307632, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37280179

RESUMEN

In this work, we innovatively assembled two types of traditional photosensitizers, that is pyridine ruthenium/ferrum (Ru(bpy)3 2+ /Fe(bpy)3 2+ ) and porphyrin/metalloporphyrin complex (2HPor/ZnPor) by covalent linkage to get a series of dual photosensitizer-based three-dimensional metal-covalent organic frameworks (3D MCOFs), which behaved strong visible light-absorbing ability, efficient electron transfer and suitable band gap for highly efficient photocatalytic hydrogen (H2 ) evolution. Rubpy-ZnPor COF achieved the highest H2 yield (30 338 µmol g-1 h-1 ) with apparent quantum efficiency (AQE) of 9.68 %@420 nm, which showed one of the best performances among all reported COF based photocatalysts. Furthermore, the in situ produced H2 was successfully tandem used in the alkyne hydrogenation with ≈99.9 % conversion efficiency. Theoretical calculations reveal that both the two photosensitizer units in MCOFs can be photoexcited and thus contribute optimal photocatalytic activity. This work develops a general strategy and shows the great potential of using multiple photosensitive materials in the field of photocatalysis.

10.
Dyslexia ; 28(4): 431-447, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36329601

RESUMEN

Dorsal stream is an important pathway for visual information transmission. As a part of the dorsal pathway, the middle temporal visual motion areas (V5/MT+) are mainly responsible for visual motion processing and the ability of visual motion processing is closely related to reading. Compared with alphabetic scripts, the visual structure of Chinese characters is more complex and there are no clear grapheme-phoneme correspondence rules. So the ability of visual analysis plays an important role in Chinese character processing. This study first investigated the brain activation of Chinese dyslexic children and children of the same chronological age when they observed coherent motion stimuli. ROI analysis indicated that only the activation of left V5/MT+ was significantly weaker in dyslexics than that in the control group. The activity of the magnocellular-dorsal stream was closely related to orthographic awareness in the combined data (two groups) and the typical children. In dyslexia group, the stronger the activation of V5/MT+ was, the worse the phonological awareness, rapid naming performance and orthographic awareness were. In short, Chinese dyslexic children were deficient in the activation of the left V5/MT+ and the activity of the magnocellular-dorsal pathway was closely related to orthographic awareness in Chinese pupils.


Asunto(s)
Dislexia , Niño , Humanos , Dislexia/diagnóstico por imagen , Imagen por Resonancia Magnética , Percepción Visual/fisiología , Lectura , China
11.
Rapid Commun Mass Spectrom ; 35(8): e9029, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33326132

RESUMEN

RATIONALE: Ginger pulp is the dried rhizome scraped off the skin which originates from Zingiber officinale Rosc., a Zingiberaceae plant. Ginger peel is the dried rhizome skin of Zingiber officinale Rosc. (Zingiberaceae). The present work aims to investigate the different chemical constituents that are related to the medicinal properties of the ginger pulp and ginger peel. METHODS: A rapid ultra-high-performance liquid chromatography/electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UHPLC/ESI-QTOF/MS) method was developed for qualitative analysis of the constituents in different polarity extracted fractions of the pulp and peel of ginger rhizomes. RESULTS: A total of 83 compounds were identified from the pulp and peel of ginger rhizomes, including 36 diarylheptanoids, 25 gingerols and 22 other compounds. Nine of these were new compounds. In total, 46, 27, 65 and 51 compounds were identified from the crude extract, petroleum ether, ethyl acetate, and n-butanol fractions of the ginger pulp, respectively, and 60, 30, 70 and 62 compounds were identified from the crude extract, petroleum ether, ethyl acetate, n-butanol fractions of the ginger peel, respectively. Each identified compound is marked on the corresponding chromatogram. CONCLUSIONS: The integrated method is sensitive and reliable for searching the different chemical constituents from different polarity extracted fractions of the ginger pulp and ginger peel. This work may provide a significant contribution to research into the medicinal properties of the ginger pulp and ginger peel.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Zingiber officinale/química , Catecoles/análisis , Catecoles/química , Diarilheptanoides/química , Alcoholes Grasos/análisis , Alcoholes Grasos/química , Extractos Vegetales/análisis , Plantas Medicinales/química , Rizoma/química
12.
J Cell Mol Med ; 24(4): 2451-2463, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31957265

RESUMEN

This study sought to find more exon mutation sites and lncRNA candidates associated with type 2 diabetes mellitus (T2DM) patients with obesity (O-T2DM). We used O-T2DM patients and healthy individuals to detect mutations in their peripheral blood by whole-exon sequencing. And changes in lncRNA expression caused by mutation sites were studied at the RNA level. Then, we performed GO analysis and KEGG pathway analysis. We found a total of 277 377 mutation sites between O-T2DM and healthy individuals. Then, we performed a DNA-RNA joint analysis. Based on the screening of harmful sites, 30 mutant genes shared in O-T2DM patients were screened. At the RNA level, mutations of 106 differentially expressed genes were displayed. Finally, a consensus mutation site and differential expression consensus gene screening were performed. In the current study, the results revealed significant differences in exon sites in peripheral blood between O-T2DM and healthy individuals, which may play an important role in the pathogenesis of O-T2DM by affecting the expression of the corresponding lncRNA. This study provides clues to the molecular mechanisms of metabolic disorders in O-T2DM patients at the DNA and RNA levels, as well as biomarkers of the risk of these disorders.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Obesidad/genética , ARN Largo no Codificante/genética , Adulto , Estudios de Casos y Controles , ADN/genética , Exones , Femenino , Expresión Génica/genética , Humanos , Masculino , Persona de Mediana Edad , Mutación/genética , ARN/genética , Secuenciación del Exoma/métodos
13.
Appl Opt ; 59(25): 7646-7651, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32902465

RESUMEN

We present the design of Ge1-xSnx-on-Si waveguide photodetectors for the applications in the C- to U-bands. The GeSn photodetectors have been studied in respect to responsivity, dark current, and bandwidth, with light butt- or evanescent-coupled from an Si waveguide. With the introduction of 4.5% Sn into Ge, the GeSn waveguide PD with evanescent-coupling exhibits high responsivity of 1.25 A/W and 3 dB bandwidth of 123.1 GHz at 1.675 µm. Further increasing the Sn composition cannot improve the absorption in the U-band significantly but does lead to poorer thermal stability and higher dark current. This work suggests a promising avenue for future high-speed high-responsivity photodetection in the C- to U-bands.

14.
J Cell Mol Med ; 22(1): 646-654, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29047214

RESUMEN

The study aimed to investigate the role of Tanshinone IIA (Tan IIA) in lipopolysaccharide (LPS)-induced acute lung injury (ALI) in its regulation of TRPM7. Wistar male rats were randomly divided into the normal saline (NS), LPS, knockout (KO) + LPS, low-dose Tan IIA (Tan-L), middle-dose Tan IIA (Tan-M), high-dose Tan IIA (Tan-H) and KO + high-dose Tan IIA (KO + Tan-H) groups. The level of tumour necrosis factor-α (TNF-α), interleukin (IL)-1ß, IL-6, TRPM7 protein expression, current density-voltage curve and Ca2+ concentration were detected through ELISA, Western blotting, electrophysiological experiment and a calcium-imaging technique, respectively. The rats in the KO + LPS, Tan-L, Tan-M, Tan-H and KO + Tan-H groups all displayed lower levels of TNF-α, IL-1ß and IL-6 than the LPS group. Rats in the KO + Tan-H group exhibited lower levels of NF-α, IL-1ß and IL-6 than rats in the Tan-H group. Elevated levels of TRPM7 protein expression in the LPS and Tan groups were detected in comparison with the NS group. However, TRPM7 protein expression in Tan-M and Tan-H groups was notably lower than in that of the LPS group. In comparison with the NS group, the LPS and Tan groups had a greater PIMs cell density and a higher concentration of Ca2+ . Contrary results were observed in the KO + LPS, Tan-H and KO + Tan-H groups. Tan IIA decreases calcium influx in PIMs and inhibits pro-inflammatory factors which provide an alleviatory effect in regards to LPS-induced ALI by suppressing TRPM7 expression.


Asunto(s)
Abietanos/uso terapéutico , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/metabolismo , Regulación hacia Abajo , Mediadores de Inflamación/metabolismo , Canales Catiónicos TRPM/metabolismo , Abietanos/farmacología , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/patología , Animales , Calcio/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos , Pulmón/efectos de los fármacos , Pulmón/patología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Tamaño de los Órganos , Oxígeno/metabolismo , Presión Parcial , Ratas Wistar , Membrana Serosa/patología , Factor de Necrosis Tumoral alfa/metabolismo
15.
J Cell Biochem ; 119(1): 701-711, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28636082

RESUMEN

This study aimed to investigate the protective effects of salvianolic acid B (SA-B) on acute lung injury (ALI) through decreasing the expressions of channel kinase's TRPM6 and TRPM7. Wistar Septic rat models were established by lipopolysaccharide (LPS), which were separated into the control, lipopolysaccharide (LPS), SA-B, SA-B + si-TRPM6, SA-B + si-TRPM7, si-TRPM6, and si-TRPM7 groups. Arterial blood gas, protein content, total white blood cell (WBC) count and the percentage of polymorphonuclear neutrophils (PMN%) were measured. Levels of TNF-α and IL-6 levels in bronchoalveolar lavage fluid (BALF) were monitored. Lung coefficient, myeloperoxidase (MPO) and superoxide dismutase (SOD) activity were conducted by MPO and SOD kit. The mRNA expressions of TRPM6 and TRPM7 were detected by qRT-PCR. Compared with the control group, the PaO2 and PaO2 /FiO2 values exhibited decreases in other group, while the PaCO2 value, protein content, total WBC, PMN%, TNF-α, IL-6 levels and lung coefficient values all increased. MPO activity in lung tissue increased, while SOD activity decreased. TRPM6 and TRPM7 expressions increased significantly. Compared with the LPS group, the SA-B, SA-B + si-TRPM6, SA-B + si-TRPM7, si-TRPM6, and si-TRPM7 groups had increased PaO2 and the PaO2 /FiO2 , while decreased PaCO2, protein content, total WBC, PMN%, TNF-α, IL-6 levels, and lung coefficient. MPO activity in lung tissue decreased while SOD activity increased. Decreased mRNA expressions of TRPM6 and TRPM7 in the SA-B, SA-B + si-TRPM6, and SA-B + si-TRPM6 groups were observed. Through decreasing the expressions of the channel kinase TRPM6 and TRPM7, SA-B protects against ALI in septic rats.


Asunto(s)
Lesión Pulmonar Aguda/prevención & control , Benzofuranos/administración & dosificación , Regulación hacia Abajo , Proteínas Serina-Treonina Quinasas/genética , Sepsis/tratamiento farmacológico , Sepsis/genética , Canales Catiónicos TRPM/genética , Lesión Pulmonar Aguda/etiología , Animales , Benzofuranos/farmacología , Líquido del Lavado Bronquioalveolar/inmunología , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Interleucina-6/metabolismo , Lipopolisacáridos/efectos adversos , Masculino , Proteínas Serina-Treonina Quinasas/metabolismo , Ratas , Ratas Wistar , Sepsis/inducido químicamente , Sepsis/metabolismo , Canales Catiónicos TRPM/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
16.
Mol Reprod Dev ; 85(1): 7-16, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29149484

RESUMEN

This study sought to identify sources of the reduced fertility of men with type 2 diabetes mellitus. Significant reductions in semen volume, sperm concentration, and total sperm count were observed in diabetic individuals, while transmission electron microscopy revealed that the structure of mitochondria in the tail of sperm from diabetic patients was damaged. Proteins potentially associated with these sperm defects were identified using proteomics. Isobaric tagging for relative and absolute quantitation labeling and high-performance liquid chromatography-tandem mass spectrometry allowed us to identify 357 proteins significantly differentially expressed in diabetic versus control semen (>1.2 or <0.83). According to gene ontology enrichment and pathway analyses, many of these differentially expressed proteins are associated with sperm function, including binding of sperm to the zona pellucida and proteasome function; of particular interest, half of these proteins were related to mitochondrial metabolism. Protein-interaction networks revealed that a decrease in Cystatin C and Dipeptidyl peptidase 4 in the mitochondria may be sources of the decreased motility of sperm from diabetic patients.


Asunto(s)
Diabetes Mellitus Tipo 2/patología , Fertilidad/fisiología , Infertilidad Masculina/patología , Mitocondrias/metabolismo , Análisis de Semen , Motilidad Espermática/fisiología , Adulto , Factor Inductor de la Apoptosis/análisis , Biomarcadores/análisis , Cromatografía Líquida de Alta Presión , Cistatina C/análisis , Diabetes Mellitus Tipo 2/etiología , Dipeptidil Peptidasa 4/análisis , Humanos , Infertilidad Masculina/complicaciones , Masculino , Persona de Mediana Edad , Proteínas Mitocondriales/análisis , Recuento de Espermatozoides , Espermatozoides/fisiología , Espectrometría de Masas en Tándem
17.
Zhonghua Nan Ke Xue ; 21(5): 424-7, 2015 May.
Artículo en Zh | MEDLINE | ID: mdl-26117940

RESUMEN

OBJECTIVE: To explore the prediction of the site for microsurgical vasoepididymostomy (VE) in the treatment of epididymal obstructive azoospermia (OA). METHODS: This study involved 56 infertile men with confirmed OA whose obstruction was suspected to be in the epididymis. Based on their medical history and results of preoperative physical examination and ultrasonography, we predicted the sites for VE. We performed surgical scrotal exploration for the status of epididymal obstruction, conducted palpation and microscopic observation for the epididymal tubules to be anastomosed, and finally decided on the sites for VE by making sure of the presence of motile sperm in the epididymal fluid of the patients. After surgery, we followed up the patients for the rate of pregnancy. RESULTS: All the patients received bilateral scrotal ultrasonography and surgical scrotal exploration, totaling 112 procedures, including 98 VE procedures. The accuracy rate of the predicted sites for VE was 80.5% (153/190) by medical history and physical examination, 80.3% (90/112) based on the results of ultrasonography, and 87.4% (90/103) according to the first selected epididymal tubules. Of the 28 patients followed up for more than 12 months, motile sperm were found in 19 (67.9% ) at 2 to 12 months and spontaneous pregnancies were achieved in 10 (35.7%), all with the anastomotic sites in the corpus or cauda. CONCLUSION: Medical history and physical examination contribute to the selection of anastomotic sites and non-invasive scrotal ultrasonography is effective and practical for positioning epididymal obstruction. The epididymal tubules with motile sperm for anastomosis could be easily obtained from the most dilated ones in indurated epididymides.


Asunto(s)
Azoospermia/cirugía , Epidídimo/cirugía , Microcirugia/métodos , Conducto Deferente/cirugía , Líquidos Corporales , Epidídimo/diagnóstico por imagen , Femenino , Humanos , Masculino , Embarazo , Índice de Embarazo , Escroto/diagnóstico por imagen , Ultrasonografía , Conducto Deferente/diagnóstico por imagen
18.
Zhonghua Nan Ke Xue ; 20(1): 14-8, 2014 Jan.
Artículo en Zh | MEDLINE | ID: mdl-24527531

RESUMEN

OBJECTIVE: To evaluate the safety and efficacy of tadalafil on demand and on time in men with erectile dysfunction. METHODS: We conducted a multi-centered randomized controlled study on 120 ED males, who were assigned to take tadalafil at 10 mg/ 20 mg on demand before sexual activity and at the same dose on time twice a week for 8 weeks. Before and at 4 and 8 weeks after treatment, and 1 month after withdrawal, we obtained the scores on IIEF-5, ED Inventory of Treatment Satisfaction (EDITS) and the short form of Psychological and Interpersonal Relationship Scales (SF-PAIRS) , and compared the safety and efficacy of medication between the two groups of patients. RESULTS: Totally, 110 patients accomplished the trial, 56 in the on-time and 54 in the on-demand group. At 4 and 8 weeks of medication and 1 month after withdrawal, the IIEF-5 scores were improved in both the on-time and on-demand groups, even more significantly in the former than in the latter at 8 weeks of treatment (21.6 +/- 2.9 vs 18.5 +/- 1.7) and 1 month after withdrawal (20.9 +/- 2.1 vs 17.9 +/- 2.3) (P < 0.05). The EDITS scores were significantly higher in the on-time than in the on-demand group at 8 weeks of treatment (31.7 +/- 6.9 vs 28.6 +/- 5.8) and 1 month after withdrawal (30.6 +/- 4.7 vs 27.9 +/- 6.5) (P < 0.05). The scores on the sexual self-confidence, spontaneity and time-concern domains of SF-PAIRS were remarkably improved after medication as compared with the baseline (P < 0.05), even more significantly in the on-time than in the on-demand group at 1 month after withdrawal. Both dosing schedules were well tolerated and no significant differences were observed in safety between the two groups. CONCLUSION: On-time dosing of tadalafil is efficacious and well tolerated in the treatment of ED, and has an even better effect than on-demand dosing at 8 weeks of medication and 1 month after withdrawal.


Asunto(s)
Carbolinas/administración & dosificación , Disfunción Eréctil/tratamiento farmacológico , Adulto , Carbolinas/uso terapéutico , Esquema de Medicación , Humanos , Masculino , Persona de Mediana Edad , Inhibidores de Fosfodiesterasa/administración & dosificación , Inhibidores de Fosfodiesterasa/uso terapéutico , Estudios Prospectivos , Tadalafilo , Resultado del Tratamiento
19.
Zhonghua Nan Ke Xue ; 20(1): 30-6, 2014 Jan.
Artículo en Zh | MEDLINE | ID: mdl-24527534

RESUMEN

OBJECTIVE: To investigate sperm function indexes that can be used to effectively evaluate the sperm donors' fertility so as to select healthy post-thaw semen samples and improve the success rate of assisted reproductive technology. METHODS: According to the pregnancy outcomes, we divided 40 donor semen samples into a high-fertility group (n = 20) and a low-fertility group (n = 20). We measured and compared the concentration, progressive motility, morphology, acrosome intactness, DNA integrity and mitochondrial membrane potential (MMP) of the post-thaw sperm between the two groups. RESULTS: There were statistically significant differences between the high- and low-fertility groups in the percentages of morphologically normal sperm ([18.50 +/- 6.10]% vs [14.42 +/- 6.44]%, P < 0.01), acrosome intactness ([86.17 +/- 4.49]% vs [80.04 +/- 7.52]%, P < 0.05) and DNA fragmentation index ([9.21 +/- 3.22]% vs [15.72 +/- 8.20]%, P < 0.05), but not in MMP ([56.75 +/- 18.80]% vs [52.23 +/- 18.86]%, P > 0.05). A significantly positive correlation was found between MMP and sperm motility (r = 0.760, P < 0.05), but not between other sperm functions and sperm concentration and motility. CONCLUSION: Sperm concentration, motility, morphology, acrosome intactness rate and DNA integrity contribute effectively to the evaluation of the fertilization capacity of post-thaw donor semen samples.


Asunto(s)
Criopreservación , Fertilización , Preservación de Semen , Espermatozoides/fisiología , Adulto , Femenino , Humanos , Masculino , Embarazo , Bancos de Esperma , Recuento de Espermatozoides , Motilidad Espermática
20.
J Ethnopharmacol ; 334: 118534, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38986753

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Chinese herb pairs are the most basic and compressed examples of Chinese herbal combinations and can be used to effectively explain the fundamental concepts of traditional Chinese medicine prescriptions. These pairings have gained significant interest due to their subtle therapeutic benefits, minimal side effects, and efficacy in treating complicated chronic conditions. The Banxia-Xiakucao Chinese herb pair (BXHP) consists of Pinellia ternata (Thunb.) Breit. (Banxia) and Prunella vulgaris L. (Xiakucao). This formula was documented in The Medical Classic of the Yellow Emperor approximately 2000 years ago,and clinical research has demonstrated that BXHP effectively treats insomnia. AIM OF THE STUDY: This study aimed to evaluate the efficacy and therapeutic mechanism of the BXHP through a comprehensive strategy involving network pharmacology, molecular docking, transcriptomics, and molecular biology experimental validation. MATERIALS AND METHODS: The composition of BXHP was characterized using the UPLC-Q-TOF-MS. The active compounds were screened to find drug-likeness compounds by analyzing the ADME data. To predict the molecular mechanism of BXHP in sleep deprivation (SD) by network pharmacology and molecular docking. We established a rat model of SD and the in vivo efficacy of BXHP was verified through the pentobarbital sodium righting reflex test, behavioral assays, enzyme-linked immunosorbent assay, transmission electron microscopy, HE staining, and Nissl staining, and the underlying molecular mechanism of BXHP in SD was revealed through transcriptomic and bioinformatic analyses in conjunction with quantitative real-time PCR, Western blot, and immunofluorescence staining. RESULTS: In the present study, we showed for the first time that BXHP reduced sleep latency, prolongs sleep duration, and improves anxiety; lowered serum CORT, IL6, TNF-α and MDA levels; decreased hypothalamic Glu levels; and elevated hypothalamic GABA and 5-HT levels in SD rats. We found 16 active compounds that acted on 583 targets, 145 of which are related to SD. By modularly dissecting the PPI network, we discovered three critical targets, Akt1, CREB1, and PRKACA, all of which play important roles in the effects of BXHP on SD. Molecular docking resulted in the identification of 16 active compounds that strongly bind to key targets. The results of GO and KEGG enrichment analyses of network pharmacology and transcriptomics focused on both the regulation of circadian rhythm and the cAMP signaling pathway, which strongly demonstrated that BXHP affects SD via the cAMP-PKA-CREB-Circadian rhythm pathway. Molecular biology experiments verified this hypothesis. Following BXHP administration, PKA and CREB phosphorylation levels were elevated in SD rats, the cAMP-PKA-CREB signaling pathway was activated, the expression levels of the biological clock genes CLOCK, p-BMAL1/BMAL1, and PER3 were increased, and the rhythmicity of the biological clock was improved. CONCLUSIONS: The active compounds in BXHP can activate the cAMP-PKA-CREB-Circadian rhythm pathway, improve the rhythmicity of the biological clock, promote sleep and ameliorate anxiety, which suggests that BXHP improves SD through a multicomponent, multitarget, multipathway mechanism. This study is important for the development of herbal medicines and clinical therapies for improving sleep deprivation.


Asunto(s)
Medicamentos Herbarios Chinos , Simulación del Acoplamiento Molecular , Farmacología en Red , Pinellia , Ratas Sprague-Dawley , Privación de Sueño , Transcriptoma , Animales , Privación de Sueño/tratamiento farmacológico , Privación de Sueño/metabolismo , Masculino , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Medicamentos Herbarios Chinos/química , Ratas , Pinellia/química , Transcriptoma/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Sueño/efectos de los fármacos , Pentobarbital/farmacología
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