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1.
Cell Prolif ; 57(2): e13551, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37743695

RESUMO

Busulfan is an antineoplastic, which is always accompanied with the abnormal of spermatogonia self-renewal and differentiation. It has been demonstrated that the omega-3 polyunsaturated fatty acids (PUFAs) benefits mature spermatozoa. However, whether omega-3 can protect endogenous spermatogonia and the detailed mechanisms are still unclear. Evaluate of spermatogenesis function (in vivo) were examined by histopathological analysis, immunofluorescence staining, and western blotting. The levels of lipid metabolites in testicular tissue were determined via liquid chromatography. We investigated the effect of lipid metabolites on Sertoli cells provided paracrine factors to regulate spermatogonia proliferation and differentiation using co-culture system. In our study, we showed that omega-3 PUFAs significantly improved the process of sperm production and elevated the quantity of both undifferentiated Lin28+ spermatogonia and differentiated c-kit+ spermatogonia in a mouse model where spermatogenic function was disrupted by busulfan. Mass spectrometry revealed an increase in the levels of several omega-3 metabolites in the testes of mice fed with omega-3 PUFAs. The eicosapentaenoic acid metabolite 12-hydroxyeicosapentaenoic acid (12-HEPE) up-regulated bone morphogenic protein 4 (BMP4) expression through GPR120-ERK1/2 pathway activation in Sertoli cells and restored spermatogonia proliferation and differentiation. Our study provides evidence that omega-3 PUFAs metabolite 12-HEPE effectively protects spermatogonia and reveals that GPR120 might be a tractable pharmacological target for fertility in men received chemotherapy or severe spermatogenesis dysfunction.


Assuntos
Bussulfano , Sêmen , Humanos , Masculino , Camundongos , Animais , Bussulfano/farmacologia , Bussulfano/metabolismo , Espermatogênese/fisiologia , Espermatogônias , Espermatozoides , Testículo/metabolismo
2.
Science ; 382(6676): 1291-1296, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38096305

RESUMO

The human body must stay within a certain temperature range for comfort and safety. However, challenges for thermoregulatory clothing exist for harsh application scenarios, such as full day/night cycles, frigid polar regions, and space travel. We developed a flexible and sustainable personal thermoregulatory clothing system by integrating a flexible organic photovoltaic (OPV) module to directly acquire energy from sunlight and bidirectional electrocaloric (EC) devices. The flexible OPV-EC thermoregulatory clothing (OETC) can extend the human thermal comfort zone from 22°-28°C to 12.5°-37.6°C with a fast thermoregulation rate. The low energy consumption and high efficiency of the EC device allows for 24 hours of controllable and dual-mode thermoregulation with 12 hours of sunlight energy input. This self-powered wearable thermoregulatory platform has a simple structure, compact design, high efficiency, and strong self-adaptability with sunlight as the sole energy source.

3.
Nano Lett ; 23(23): 11272-11279, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38038230

RESUMO

Thermogalvanic hydrogels have been quickly developed and are widely used in thermal energy harvesting. However, the freezing behaviors of thermogalvanic hydrogels at subzero temperatures greatly limit their practical applications. Herein, we design an antifreezing thermogalvanic hydrogel based on [Fe(CN)6]3-/4- ions for thermoelectric power generation in ultralow temperature environments. The antifreezing thermogalvanic hydrogels show excellent flexibility at -80 °C owing to the hydrogen bonding between ethylene glycol and water molecules. Even after 500 cyclic tensile strains, the thermogalvanic hydrogels can still maintain excellent mechanical stability, and the Seebeck coefficient is as high as 1.43 mV/K, corresponding to a large retention rate of ∼95%. Moreover, we demonstrate a wearable thermoelectric shoe based on antifreezing thermogalvanic hydrogels for harvesting human thermal energy in a simulated winter environment of -30 °C, and the electricity can drive a green LED. This work provides important guidance for the design and optimization of antifreezing thermogalvanic hydrogels.

4.
ACS Nano ; 17(20): 20299-20307, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37831602

RESUMO

Thermal management textiles provide an energy-efficient strategy for personal thermal comfort by regulating heat flow between the human body and the environment. However, textiles with a single heating or cooling mode cannot realize temperature regulation under dynamic weather. Furthermore, monocolor textiles do not satisfy aesthetic requirements in a garment. Here, we develop a thermochromic (TC) conductive fiber with a coaxial structure composed of a conductive core and thermochromic shell. The TC conductive fiber-woven fabric has the ability of low-energy dynamic thermal management by combining Joule heating and modulation of solar absorption. Compared with commercial white fabrics, TC conductive fabrics exhibit a maximum temperature drop of 2.5 K, while the temperature of colored commercial fabrics is 7.5-16 K higher than that of commercial white fabrics in the hot. In the cold, the combination of Joule heating and the photothermal effect can provide desired thermal comfort for humans. Meanwhile, heat obtained from solar absorption brings the temperature of a fabric to a predetermined level, which saves energy of 625 W/m2 compared to a conductive-fiber-based textile. In addition, TC conductive fabrics with trichromatic evolution provide a sensitive and instant temperature visualization capable of identification of invisible and intense infrared radiation. These results provide another path to expand potential applications of wearable, flexible electronics.

5.
Mol Cell Endocrinol ; 578: 112076, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37769867

RESUMO

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder affecting women of reproductive age and is a significant cause of female subfertility. Our previous research demonstrated that the abnormal palmitoylation of heat shock protein-90α (HSP90α) plays a role in the development of PCOS. However, the palmitoyl acyltransferases in HSP90α palmitoylation remain poorly understood. Herein, we identified ZDHHC17 as a major palmitoyl acyltransferase for HSP90α palmitoylation in granulosa cells. ZDHHC17 protein expression was diminished under excess androgen conditions in vitro and in vivo. Consistently, ovarian ZDHHC17 expression was found to be attenuated in patients with PCOS. ZDHHC17 depletion decreased HSP90α palmitoylation levels and hampered the conversion of androgen to estrogen via CYP19A1. Furthermore, ZDHHC17-mediated regulation of CYP19A1 expression was dependent on HSP90α palmitoylation. Our findings reveal that the regulatory role of HSP90α palmitoylation by ZDHHC17 is critical in PCOS pathophysiology and provide insights into the role of ZDHHC17 in reproductive endocrinology.

6.
Geroscience ; 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37532927

RESUMO

Female infertility due to declining oocyte quality with age remains a significant challenge for patients and physicians, despite extensive research efforts. Recent studies suggest that microRNAs (miRNAs), which respond to various stressors in the aging process, may provide a promising solution. With the approval of small RNA drugs for clinical use, miRNA-based treatment of oocyte aging appears to be a viable option. Through high-throughput sequencing, miR-425-5p was identified as the only miRNA elevated under natural aging and oxidative stress. Microinjection of inhibitors to inhibit miR-425-5p effectively improved compromised phenotypes of old oocytes in vitro. Further investigation revealed that Crebzf acts as a mediator of miR-425-5p's age-related functions in old oocytes. In vivo treatment with miR-425-5p antagomirs significantly improved impaired oocyte development in reproductively old females by targeting Crebzf. Single-cell RNA sequencing revealed that Crebzf plays a vital role in regulating mRNAs targeting histone H3, trimethylated lysine 4 (H3K4me3), a crucial marker for transcriptional silencing. Overexpression of miR-425-5p could hinder oocyte maturation by downregulating Crebzf expression and disrupting transcriptional regulation. Our findings provide new insights into the potential of miR-425-5p antagomirs as a treatment for female infertility and highlight an elegant mechanism by which miR-425-5p inhibition of Crebzf inhibits a developmental switch in GV oocytes by regulating a group of histone methyltransferase mRNAs.

7.
Reprod Biomed Online ; 47(4): 103238, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37573751

RESUMO

RESEARCH QUESTION: Is early embryo development in mice influenced by RNA binding protein with multiple splicing 2 (RBPMS2), a maternal factor that accumulates and is stored in the cytoplasm of mature oocytes? DESIGN: The expression patterns of RBPMS2 in mouse were analysed using quantitative real-time PCR (qRT PCR) and immunofluorescence staining. The effect of knockdown of RBPMS2 on embryo development was evaluated through a microinjection of specific morpholino or small interfering RNA. RNA sequencing was performed for mechanistic analysis. The interaction between RBPMS2 and the bone morphogenetic protein (BMP) pathway was studied using BMP inhibitor and activator. The effect on the localization of E-cadherin was determined by immunofluorescence staining. RESULTS: Maternal protein RBPMS2 is highly expressed in mouse oocytes, and knockdown of RBPMS2 inhibits embryo development from the morula to the blastocyst stage. Mechanistically, RNA sequencing showed that the differentially expressed genes were enriched in the transforming growth factor-ß (TGF-ß) signalling pathway. BMPs are members of the TGF-ß superfamily of growth factors. It was found that the addition of BMP inhibitor to the culture medium led to a morula-stage arrest, similar to that seen in RBPMS2 knockdown embryos. This morula-stage arrest defect caused by RBPMS2 knockdown was partially rescued by BMP activator. Furthermore, the localization of E-cadherin to the membrane was impaired in response to a knockdown of RBPMS2 or inhibition of the BMP pathway. CONCLUSION: This study suggests that RBPMS2 activates the BMP pathway and thus influences the localization of E-cadherin, which is important for early mouse embryo development during blastocyst formation.


Assuntos
Proteínas Morfogenéticas Ósseas , Desenvolvimento Embrionário , Animais , Camundongos , Blastocisto/metabolismo , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Desenvolvimento Embrionário/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Fator de Crescimento Transformador beta/metabolismo
8.
J Ovarian Res ; 16(1): 138, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37443082

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disorder that frequently exhibits low-grade inflammation, pro-oxidant activity, and gut dysbiosis. PCOS has become one of the leading causes of female infertility worldwide. Recently, omega-3 polyunsaturated fatty acids (PUFAs) have been proven to benefit metabolic disorders in PCOS patients. However, its roles in the regulation of metabolic and endocrinal balances in PCOS pathophysiology are not clear. In the present study, we aimed to explore how omega-3 PUFAs alleviate ovarian dysfunction and insulin resistance in mice with dehydroepiandrosterone (DHEA)-induced PCOS by modulating the gut microbiota. METHODS: We induced PCOS in female mice by injecting them with DHEA and then treated them with omega-3 PUFAs. 16S ribosomal DNA (rDNA) amplicon sequencing, fecal microbiota transplantation (FMT) and antibiotic treatment were used to evaluate the role of microbiota in the regulation of ovarian functions and insulin resistance (IR) by omega-3 PUFAs. To further investigate the mechanism of gut microbiota on omega-3-mediated ovarian and metabolic protective effects, inflammatory and oxidative stress markers in ovaries and thermogenic markers in subcutaneous and brown adipose tissues were investigated. RESULTS: We found that oral supplementation with omega-3 PUFAs ameliorates the PCOS phenotype. 16S rDNA analysis revealed that omega-3 PUFA treatment increased the abundance of beneficial bacteria in the gut, thereby alleviating DHEA-induced gut dysbiosis. Antibiotic treatment and FMT experiments further demonstrated that the mechanisms underlying omega-3 benefits likely involve direct effects on the ovary to inhibit inflammatory cytokines such as IL-1ß, TNF-α and IL-18. In addition, the gut microbiota played a key role in the improvement of adipose tissue morphology and function by decreasing multilocular cells and thermogenic markers such as Ucp1, Pgc1a, Cited and Cox8b within the subcutaneous adipose tissues. CONCLUSION: These findings indicate that omega-3 PUFAs ameliorate androgen-induced gut microbiota dysbiosis. The gut microbiota plays a key role in the regulation of omega-3-mediated IR protective effects in polycystic ovary syndrome mice. Moreover, omega-3 PUFA-regulated improvements in the ovarian dysfunction associated with PCOS likely involve direct effects on the ovary to inhibit inflammation. Our findings suggest that omega-3 supplementation may be a promising therapeutic approach for the treatment of PCOS by modulating gut microbiota and alleviating ovarian dysfunction and insulin resistance.


Assuntos
Suplementos Nutricionais , Ácidos Graxos Ômega-3 , Microbioma Gastrointestinal , Síndrome do Ovário Policístico , Animais , Feminino , Camundongos , Desidroepiandrosterona/toxicidade , Microbioma Gastrointestinal/fisiologia , Resistência à Insulina , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/fisiopatologia , Ácidos Graxos Ômega-3/uso terapêutico
9.
Cell Death Discov ; 9(1): 163, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37188682

RESUMO

In recent years, the postponement of childbearing has become a critical social issue. Male fertility is negatively associated with age because of testis aging. Spermatogenesis is impaired with age, but the molecular mechanism remains unknown. The dynamic posttranslational modification O-linked N-acetylglucosamine (O-GlcNAc), which is a type of monosaccharide modification, has been shown to drive the process of aging in various systems, but it has not yet been investigated in the testis and male reproductive aging. Thus, this study aims to investigate the alteration of O-GlcNAc with aging and explore the role of O-GlcNAc in spermatogenesis. Here, we demonstrate that the decline in spermatogenesis in aged mice is associated with elevation of O-GlcNAc. O-GlcNAc is specifically localized in differentiating spermatogonia and spermatocytes, indicating its crucial role in meiotic initiation and progression. Mimicking the age-related elevation of O-GlcNAc in young mice by disabling O-GlcNAcase (OGA) using the chemical inhibitor Thiamet-G can recapitulate the impairment of spermatogenesis in aged mice. Mechanistically, the elevation of O-GlcNAc in the testis leads to meiotic pachytene arrest due to defects in synapsis and recombination. Furthermore, decreasing O-GlcNAc in aged testes using an O-GlcNAc transferase (OGT) inhibitor can partially rescue the age-related impairment of spermatogenesis. Our results highlight that O-GlcNAc, as a novel posttranslational modification, participates in meiotic progression and drives the impairment of spermatogenesis during aging.

10.
Adv Mater ; 35(32): e2300696, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37222174

RESUMO

Thermocells can continuously convert heat into electricity, and they are widely used to power wearable electronic devices. However, they have a risk of leakage and poor mechanical properties. Although quasi-solid ionic thermocells can overcome the issue of electrolyte leakage, the trade-off between their excellent mechanical properties and high thermopower remains a major challenge. In this study, stretching-induced crystallization and the thermoelectric effect are combined to propose a high-strength quasi-solid stretchable polyvinyl alcohol thermogalvanic thermocell (SPTC) with a large tensile strength of 19 MPa and high thermopower of 6.5 mV K-1 . The SPTC exhibits a high stretchability of 1300%, ultrahigh toughness of 163.4 MJ m-3 , and high specific output power density of 1969 µW m-2  K-2 . These comprehensive properties are superior to those of previously reported quasi-solid stretchable thermogalvanic thermocells. The use of SPTC-based systems in wearable devices for energy-autonomous strain sensors and health monitoring is demonstrated. This can facilitate the rapid implementation of sustainable wearable electronics in the Internet of Things era.

11.
J Ovarian Res ; 16(1): 87, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37120599

RESUMO

n-3 PUFAs are classic antioxidant that can be used to treat follicular dysplasia and hyperinsulinemia caused by excessive oxidative stress in PCOS women. To investigate the effect of n-3 PUFA supplementation on the oocyte quality of polycystic ovary syndrome (PCOS) mice during in vitro maturation, a PCOS mouse model was established by dehydroepiandrosterone (DHEA). The GV oocytes of the control and PCOS groups were collected and cultured in vitro with or without n-3 PUFAs. After 14 h, the oocytes were collected. Our data demonstrated that the oocyte maturation rate of PCOS mice significantly increased after the addition of 50 µM n-3 PUFAs. The results of immunofluorescence showed that the abnormal rates of spindles and chromosomes in the PCOS + n-3 PUFA group were lower than those in the PCOS group. The mRNA expression of an antioxidant-related gene (Sirt1) and DNA damage repair genes (Brca1/Msh2) was found to be significantly rescued after n-3 treatment. Additionally, the results of living cell staining showed that the addition of n-3 PUFAs could reduce the levels of reactive oxygen species and mitochondrial superoxide in PCOS oocytes. In conclusion, the addition of 50 µM n-3 PUFAs during the in vitro maturation of PCOS mouse oocytes can improve the maturation rate by reducing the level of oxidative stress and the rate of spindle/chromosome abnormalities, providing valuable support during the IVM process.


Assuntos
Ácidos Graxos Ômega-3 , Síndrome do Ovário Policístico , Humanos , Feminino , Animais , Camundongos , Técnicas de Maturação in Vitro de Oócitos , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/metabolismo , Ácidos Graxos Ômega-3/farmacologia , Ácidos Graxos Ômega-3/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Oócitos/metabolismo , Suplementos Nutricionais
12.
iScience ; 26(3): 106131, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36879822

RESUMO

Ovarian granulosa cells (GCs) in the follicle are the important mediator of steroidogenesis and foster oocyte maturation. Evidences suggested that the function of GCs could be regulated by S-palmitoylation. However, the role of S-palmitoylation of GCs in ovarian hyperandrogenism remains elusive. Here, we demonstrated that the protein from GCs in ovarian hyperandrogenism phenotype mouse group exhibits lower palmitoylation level compared with that in the control group. Using S-palmitoylation-enriched quantitative proteomics, we identified heat shock protein isoform α (HSP90α) with lower S-palmitoylation levels in ovarian hyperandrogenism phenotype group. Mechanistically, S-palmitoylation of HSP90α modulates the conversion of androgen to estrogens via the androgen receptor (AR) signalling pathway, and its level is regulated by PPT1. Targeting AR signaling by using dipyridamole attenuated ovarian hyperandrogenism symptoms. Our data help elucidate ovarian hyperandrogenism from perspective of protein modification and provide new evidence showing that HSP90α S-palmitoylation modification might be a potential pharmacological target for ovarian hyperandrogenism treatment.

13.
Toxicol Lett ; 376: 1-12, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36642205

RESUMO

As a widespread environmental contaminant, short chain chlorinated paraffins (SCCPs) has attracted great attention. However, the toxicity of SCCPs on male reproductive system remains ambiguous. In this study, we treated mice with SCCPs by gavage and investigated the toxic effects of SCCPs on testis. According to the results, the sperm parameters of mice were significantly reduced after exposure to 1, 10, 100 mg/kg body mass per day SCCPs for 35 days. SCCPs resulted in disorderly arranged seminiferous epithelium and increased apoptotic cells in testes. Both in vivo and in vitro experiments indicated that the oxidative stress was induced after SCCPs exposure, and dysfunction of nuclear factor erythroid-related factor (NRF2) signaling pathway played a role in this process. Moreover, resveratrol, an NRF2 activator, could alleviate the damage of SCCPs onmale reproductive system. Our study indicated that oxidative stress is the key point for explaining the testicular toxicity caused by SCCPs, and NRF2 could be used as a potential target for clinical treatment to alleviate the reproductive toxicity induced by SCCPs.


Assuntos
Hidrocarbonetos Clorados , Parafina , Animais , Masculino , Camundongos , China , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/toxicidade , Fator 2 Relacionado a NF-E2/genética , Parafina/toxicidade , Parafina/análise , Sêmen/química , Testículo , Estresse Oxidativo
14.
Adv Mater ; 35(15): e2209181, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36690602

RESUMO

More than 55% of electronic failures are caused by damage from localized overheating. Up to now, there is still no efficient method for targeted temperature control against localized overheating. Although some existing thermal management devices handle this issue by full coverage cooling, it generates a lot of useless energy consumption. Here, a highly efficient pixel-matrix electrocaloric (EC) cooling device is reported, which can realize a targeted and differential thermal management. The modified poly(vinylidene fluoride-tertrifluoroethylene-chlorofluoroethylene) reaches a large adiabatic temperature change of 7.8 K and is more suitable for thermal transfer and electrostatic actuation at high frequencies. All active pixels in the EC cooling device exhibit a stable temperature span of 4.6 K and a heat flux of 62 mW cm-2 , which is more than twice that of the one-layer EC device. Each refrigeration pixel can be independently controlled and effectively cooled down the localized overheating site(s) in situ. The surface temperature of the simulated central processing unit decreases by 33.2 K at 120 s after applying this EC device. Such a compact, embeddable, low cost, and active solid-state pixel-matrix cooling device has great potential for localized overheating protection in microelectronics.

15.
Proc Natl Acad Sci U S A ; 119(38): e2207353119, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36095218

RESUMO

Radiative thermal management provides a zero-energy strategy to reduce the demands of fossil energy for active thermal management. However, whether solar heating or radiative cooling, one-way temperature control will exacerbate all-season energy consumption during hot summers or cold winters. Inspired by the Himalayan rabbit's hair and Mimosa pudica's leaves, we proposed a dual-mode thermal-management device with two differently selective electromagnetic spectrums. The combination of visible and infrared "thermochromism" enables this device to freely switch between solar heating and radiative cooling modes by spontaneously perceiving the temperature without any external energy consumption. Numerical prediction shows that a dual-mode device exhibits an outstanding potential for all-season energy saving in terms of thermal management beyond most static or single-wavelength, range-regulable, temperature-responsive designs. Such a scalable and cost-efficient device represents a more efficient radiative thermal-management strategy toward applying in a practical scenario with dynamic daily and seasonal variations.

16.
Nano Lett ; 22(16): 6560-6566, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35947031

RESUMO

Cooling based on the electrocaloric effect (ECE) is a promising solution to environmental and energy efficiency problems of vapor-compression refrigeration. Ferroelectric polymer-ceramics nanocomposites, integrating high electric breakdown of organic ferroelectrics and large EC strength of ceramics, are attractive EC materials. Here, we tuned the orientation of Ba0.67Sr0.33TiO3 nanofibers (BST nfs) in the P(VDF-TrFE-CFE) polymer. When the nfs were aligned parallel to the field, a ΔT of 11.3 K with an EC strength of 0.16 K·m/MV was achieved in the blends. The EC strength not only surpasses advanced nanocomposites but also is comparable to ferroelectric ceramics. The simulation indicates that a significantly higher electric field is concentrated in polymer regions around the ends of the orientated nfs, contributing to easier flipping of polymer chains for large ECE. This work provides a new method to obtain large ECE in composites for next-generation refrigeration.

17.
Nat Commun ; 13(1): 4874, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35985989

RESUMO

Reducing needs for heating and cooling from fossil energy is one of the biggest challenges, which demand accounts for almost half of global energy consumption, consequently resulting in complicated climatic and environmental issues. Herein, we demonstrate a high-performance, intelligently auto-switched and zero-energy dual-mode radiative thermal management device. By perceiving temperature to spontaneously modulate electromagnetic characteristics itself, the device achieves ~859.8 W m-2 of average heating power (∼91% of solar-thermal conversion efficiency) in cold and ~126.0 W m-2 of average cooling power in hot, without any external energy consumption during the whole process. Such a scalable, cost-effective device could realize two-way temperature control around comfortable temperature zone of human living. A practical demonstration shows that the temperature fluctuation is reduced by ~21 K, compared with copper plate. Numerical prediction indicates that this real zero-energy dual-mode thermal management device has a huge potential for year-round energy saving around the world and provides a feasible solution to realize the goal of Net Zero Carbon 2050.

18.
Redox Biol ; 54: 102380, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35803125

RESUMO

Blood-testis barrier (BTB) damage promotes spermatogenesis dysfunction, which is a critical cause of male infertility. Dyslipidemia has been correlated with male infertility, but the major hazardous lipid and the underlying mechanism remains unclear. In this study, we firstly discovered an elevation of palmitic acid (PA) and a decrease of inhibin B in patients with severe dyszoospermia, which leaded us to explore the effects of PA on Sertoli cells. We observed a damage of BTB by PA. PA penetration to endoplasmic reticulum (ER) and its damage to ER structures were exhibited by microimaging and dynamic observation, and consequent ER stress was proved to mediate PA-induced Sertoli cell barrier disruption. Remarkably, we demonstrated a critical role of aberrant protein palmitoylation in PA-induced Sertoli cell barrier dysfunction. An ER protein, Calnexin, was screened out and was demonstrated to participate in this process, and suppression of its palmitoylation showed an ameliorating effect. We also found that ω-3 poly-unsaturated fatty acids down-regulated Calnexin palmitoylation, and alleviated BTB dysfunction. Our results indicate that dysregulated palmitoylation induced by PA plays a pivotal role in BTB disruption and subsequent spermatogenesis dysfunction, suggesting that protein palmitoylation might be therapeutically targetable in male infertility.


Assuntos
Barreira Hematotesticular , Infertilidade Masculina , Barreira Hematotesticular/metabolismo , Calnexina/metabolismo , Calnexina/farmacologia , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/metabolismo , Lipoilação , Masculino , Ácido Palmítico/farmacologia , Espermatogênese/fisiologia
19.
Nano Lett ; 22(12): 4925-4932, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35686917

RESUMO

Daytime subambient radiative cooling provides a powerful strategy for realizing sustainable thermal management without any external energy consumption. However, in practical situations a dazzling white or silver appearance is undesirable for aesthetic and functional reasons. Therefore, developing colored radiative cooling materials is greatly significant for more potential applications but remains a big challenge so far. Here, we reported a flexible colored radiative cooler based on interferometric retroreflection-induced structural color, which resolves the conflict between a colorful appearance for aesthetics and high solar reflection for cooling. All colored radiative coolers achieve subambient cooling of 4 K even under sunshine stronger than 1000 W/m2, while the same color commercial paints are 9-27 K higher than the ambient. Such a flexible, scalable, and low cost colored radiative cooler is expected to replace commercial paint in a practical scenario with aesthetic and cooling requirements, enabling substantial reduction in carbon emission and energy consumption.

20.
Nano Lett ; 22(8): 3417-3424, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35404612

RESUMO

Power generation through harvesting human thermal energy provides an ideal strategy for self-powered wearable design. However, existing thermoelectric fibers, films, and blocks have small power generation capacity and poor flexibility, which hinders the development of self-powered wearable electronics. Here, we report a multifunctional superelastic graphene-based thermoelectric (TE) sponge for wearable electronics and thermal management. The sponge has a high Seebeck coefficient of 49.2 µV/K and a large compressive strain of 98%. After 10 000 cyclic compressions at 30% strain, the sponge shows excellent mechanical and TE stability. A wearable sponge array TE device was designed to drive medical equipment for monitoring physiological signals by harvesting human thermal energy. Furthermore, a 4 × 4 array TE device placed on the surface of a normal working Central Processing Unit (CPU) can generate a stable voltage and reduce the CPU temperature by 8 K, providing a feasible strategy for simultaneous power generation and thermal management.


Assuntos
Grafite , Dispositivos Eletrônicos Vestíveis , Eletrônica , Temperatura Alta , Humanos , Temperatura
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