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1.
Molecules ; 29(16)2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39202799

RESUMO

Single-atom catalysts (SACs) have attracted extensive attention due to their unique catalytic properties and wide range of applications. Advanced characterization techniques, such as energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy, and X-ray absorption fine-structure spectroscopy, have been used to investigate the elemental compositions, structural morphologies, and chemical bonding states of SACs in detail, aiming at unraveling the catalytic mechanism. Meanwhile, theoretical calculations, such as quantum chemical calculations and kinetic simulations, were used to predict the catalytic reaction pathways, active sites, and reaction kinetic behaviors of SACs, providing theoretical guidance for the design and optimization of SACs. This review overviews advanced characterization techniques and theoretical calculations for SACs in Fenton-like chemistry. Moreover, this work highlights the importance of advanced characterization techniques and theoretical calculations in the study of SACs and provides perspectives on the potential applications of SACs in the field of environmental remediation and the challenges of practical engineering.

2.
Environ Sci Technol ; 57(37): 14071-14081, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37681682

RESUMO

Currently, the lack of model catalysts limits the understanding of the catalytic essence. Herein, we report the functional group modification of model single atom catalysts (SACs) with an accurately regulated electronic structure for accelerating the sluggish kinetics of the Fenton-like reaction. The amino-modified cobalt phthalocyanine anchored on graphene (CoPc/G-NH2) shows superior catalytic performance in the peroxymonosulfate (PMS) based Fenton-like reaction with Co mass-normalized pseudo-first-order reaction rate constants (kobs, 0.2935 min-1), which is increased by 4 and 163 times compared to those of CoPc/G (0.0737 min-1) and Co3O4/G (0.0018 min-1). Density functional theory (DFT) calculations demonstrate that the modification of the -NH2 group narrows the gap between the d-band center and the Fermi level of a single Co atom, which strengthens the charge transfer rate at the reaction interface and reduces the free energy barrier for the activation of PMS. Moreover, the scale-up experiment realizes 100% phenol removal at 7200-bed volumes during 240 h continuous operation without obvious decline in catalytic performance. This work provides in-depth insight into the catalytic mechanism of Fenton-like reactions and demonstrates the electronic engineering of SACs as an effective strategy for improving the Fenton-like activity to achieve the goal of practical application.


Assuntos
Eletrônica , Poluentes Ambientais , Catálise , Cobalto
3.
Environ Sci Technol ; 57(37): 14046-14057, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37658810

RESUMO

Precisely identifying the atomic structures in single-atom sites and establishing authentic structure-activity relationships for single-atom catalyst (SAC) coordination are significant challenges. Here, theoretical calculations first predicted the underlying catalytic activity of Fe-NxC4-x sites with diverse first-shell coordination environments. Substituting N with C to coordinate with the central Fe atom induces an inferior Fenton-like catalytic efficiency. Then, Fe-SACs carrying three configurations (Fe-N2C2, Fe-N3C1, and Fe-N4) fabricate facilely and demonstrate that optimized coordination environments of Fe-NxC4-x significantly promote the Fenton-like catalytic activity. Specifically, the reaction rate constant increases from 0.064 to 0.318 min-1 as the coordination number of Fe-N increases from 2 to 4, slightly influencing the nonradical reaction mechanism dominated by 1O2. In-depth theoretical calculations unveil that the modulated coordination environments of Fe-SACs from Fe-N2C2 to Fe-N4 optimize the d-band electronic structures and regulate the binding strength of peroxymonosulfate on Fe-NxC4-x sites, resulting in a reduced energy barrier and enhanced Fenton-like catalytic activity. The catalytic stability and the actual hospital sewage treatment capacity also showed strong coordination dependency. This strategy of local coordination engineering offers a vivid example of modulating SACs with well-regulated coordination environments, ultimately maximizing their catalytic efficiency.


Assuntos
Eletrônica , Hospitais , Catálise , Ferro , Esgotos
4.
Environ Sci Technol ; 57(29): 10804-10815, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37431633

RESUMO

Carbon nanotubes (CNTs) and their derivatives have been widely exploited to activate various oxidants for environmental remediation. However, the intrinsic mechanism of CNTs-driven periodate (PI) activation remains ambiguous, which significantly impedes their scientific progress toward practical application. Here, we found that CNTs can strongly boost PI activation for the oxidation of various phenols. Reactive oxygen species analysis, in situ Raman characterization, galvanic oxidation process experiments, and electrochemical tests revealed that CNTs could activate PI to form high-potential metastable intermediates (CNTs-PI*) rather than produce free radicals and 1O2, thereby facilitating direct electron transfer from the pollutants to PI. Additionally, we analyzed quantitative structure-activity relationships between rate constants of phenols oxidation and double descriptors (e.g., Hammett constants and logarithm of the octanol-water partition coefficient). The adsorption of phenols on CNT surfaces and their electronic properties are critical factors affecting the oxidation process. Besides, in the CNTs/PI system, phenol adsorbed the CNT surfaces was oxidized by the CNTs-PI* complexes, and products were mainly generated via the coupling reaction of phenoxyl radical. Most of the products adsorbed and accumulated on the CNT surfaces realized phenol removal from the bulk solution. Such a unique non-mineralization removal process achieved an extremely high apparent electron utilization efficiency of 378%. The activity evaluation and theoretical calculations of CNT derivatives confirmed that the carbonyl/ketonic functional groups and double-vacancy defects of the CNTs were the primary active sites, where high-oxidation-potential CNTs-PI* were formed. Further, the PI species could achieve a stoichiometric decomposition into iodate, a safe sink of iodine species, without the generation of typical iodinated byproducts. Our discovery provides new mechanistic insight into CNTs-driven PI activation for the green future of environmental remediation.


Assuntos
Nanotubos de Carbono , Nanotubos de Carbono/química , Fenol , Oxirredução , Fenóis
5.
Environ Sci Technol ; 57(41): 15667-15679, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37801403

RESUMO

The nanoconfinement effect in Fenton-like reactions shows great potential in environmental remediation, but the construction of confinement structure and the corresponding mechanism are rarely elucidated systematically. Herein, we proposed a novel peroxymonosulfate (PMS) activation system employing the single Fe atom supported on mesoporous N-doped carbon (FeSA-MNC, specific surface area = 1520.9 m2/g), which could accelerate the catalytic oxidation process via the surface-confinement effect. The degradation activity of the confined system was remarkably increased by 34.6 times compared to its analogue unconfined system. The generation of almost 100% high-valent iron-oxo species was identified via 18O isotope-labeled experiments, quenching tests, and probe methods. The density functional theory illustrated that the surface-confinement effect narrows the gap between the d-band center and Fermi level of the single Fe atom, which strengthens the charge transfer rate at the reaction interface and reduces the free energy barrier for PMS activation. The surface-confinement system exhibited excellent pollutant degradation efficiency, robust resistance to coexisting matter, and adaptation of a wide pH range (3.0-11.0) and various temperature environments (5-40 °C). Finally, the FeSA-MNC/PMS system could achieve 100% sulfamethoxazole removal without significant performance decline after 10,000-bed volumes. This work provides novel and significant insights into the surface-confinement effect in Fenton-like chemistry and guides the design of superior oxidation systems for environmental remediation.


Assuntos
Ferro , Peróxidos , Ferro/química , Peróxidos/química , Oxirredução , Carbono
6.
Environ Sci Technol ; 57(50): 21416-21427, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38064647

RESUMO

Accurately controlling catalytic activity and mechanism as well as identifying structure-activity-selectivity correlations in Fenton-like chemistry is essential for designing high-performance catalysts for sustainable water decontamination. Herein, active center size-dependent catalysts with single cobalt atoms (CoSA), atomic clusters (CoAC), and nanoparticles (CoNP) were fabricated to realize the changeover of catalytic activity and mechanism in peroxymonosulfate (PMS)-based Fenton-like chemistry. Catalytic activity and durability vary with the change in metal active center sizes. Besides, reducing the metal size from nanoparticles to single atoms significantly modulates contributions of radical and nonradical mechanisms, thus achieving selective/nonselective degradation. Density functional theory calculations reveal evolutions in catalytic mechanisms of size-dependent catalytic systems over different Gibbs free energies for reactive oxygen species generation. Single-atom site contact with PMS is preferred to induce nonradical mechanisms, while PMS dissociates and generates radicals on clusters and nanoparticles. Differences originating from reaction mechanisms endow developed systems with size-dependent selectivity and mineralization for treating actual hospital wastewater in column reactors. This work brings an in-depth understanding of metal size effects in Fenton-like chemistry and guides the design of intelligent catalysts to fulfill the demand of specific scenes for water purification.


Assuntos
Cobalto , Descontaminação , Catálise , Água
7.
Environ Sci Technol ; 57(8): 3334-3344, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36734031

RESUMO

Accelerating the rate-limiting Fe3+/Fe2+ circulation in Fenton reactions through the addition of reducing agents (or co-catalysts) stands out as one of the most promising technologies for rapid water decontamination. However, conventional reducing agents such as hydroxylamine and metal sulfides are greatly restricted by three intractable challenges: (1) self-quenching effects, (2) heavy metal dissolution, and (3) irreversible capacity decline. To this end, we, for the first time, introduced redox-active polymers as electron shuttles to expedite the Fe3+/Fe2+ cycle and promote H2O2 activation. The reduction of Fe3+ mainly took place at active N-H or O-H bonds through a proton-coupled electron transfer process. As electron carriers, H atoms at the solid phase could effectively inhibit radical quenching, avoid metal dissolution, and maintain long-term reducing capacity via facile regeneration. Experimental and density functional theory (DFT) calculation results indicated that the activity of different polymers shows a volcano curve trend as a function of the energy barrier, highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gap, and vertical ionization potential. Thanks to the appropriate redox ability, polyaniline outperforms other redox-active polymers (e.g., poypyrrole, hydroquinone resin, poly(2,6-diaminopyridine), and hexaazatrinaphthalene framework) with a highest iron reduction capacity up to 5.5 mmol/g, which corresponds to the state transformation from leucoemeraldine to emeraldine. Moreover, the proposed system exhibited high pollutant removal efficiency in a flow-through reactor for 8000 bed volumes without an obvious decline in performance. Overall, this work established a green and sustainable oxidation system, which offers great potential for practical organic wastewater remediation.


Assuntos
Peróxido de Hidrogênio , Ferro , Ferro/química , Peróxido de Hidrogênio/química , Substâncias Redutoras , Elétrons , Oxirredução
8.
BMC Neurosci ; 23(1): 50, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945502

RESUMO

BACKGROUND: Evidences indicate that inflammasome compounds participate in amyotrophic lateral sclerosis (ALS), a fatal progressive motoneuron degenerative disease. Researchers have observed the expressions of nucleotide oligomerization domain (NOD)-like receptor protein 3 (NLRP3) related inflammasome components in specific regions of the central nervous system in different ALS models, but the cellular spatiotemporal evolution of this canonical inflammasome pathway and pyroptosis during ALS progression are unclear. METHODS: The spinal cords of hSOD1G93A mice (ALS mice) and age-matched littermates (CON mice) were dissected at pre-symptomatic stage (60 d), early- symptomatic stage (95 d), symptomatic stage (108 d) and late-symptomatic stage (122 d) of the disease. By using Nissl staining, double immunofluorescence labelling, qRT-PCR or western blot, we detected morphology change and the expression, cellular location of GSDMD, NLRP3, caspase-1 and IL-1ß in the ventral horn of lumbar spinal cords over the course of disease. RESULTS: Neural morphology changes and GSDMD+/NeuN+ double positive cells were observed in ventral horn from ALS mice even at 60 d of age, even though there were no changes of GSDMD mRNA and protein expressions at this stage compared with CON mice. With disease progression, compared with age-matched CON mice, increased expressions of GSDMD, NLRP3, activated caspase-1 and IL-1ß were detected. Double immunofluorescence labeling revealed that NLRP3, caspase-1, IL-1ß positive signals mainly localized in ventral horn neurons at pre- and early-symptomatic stages. From symptomatic stage to late-symptomatic stage, robust positive signals were co-expressed in reactive astrocytes and microglia. CONCLUSIONS: Early activation of the canonical NLRP3 inflammasome induced pyroptosis in ventral horn neurons, which may participate in motor neuron degeneration and initiate neuroinflammatory processes during ALS progression.


Assuntos
Esclerose Lateral Amiotrófica , Inflamassomos , Esclerose Lateral Amiotrófica/genética , Animais , Caspases , Modelos Animais de Doenças , Inflamassomos/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Superóxido Dismutase , Superóxido Dismutase-1/genética
9.
Int J Mol Sci ; 23(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36361808

RESUMO

Heterozygous variants in the hepatocyte nuclear factor 1a (HNF1a) cause MODY3 (maturity-onset diabetes of the young, type 3). In this study, we found a case of novel HNF1a p.Gln125* (HNF1a-Q125ter) variant clinically. However, the molecular mechanism linking the new HNF1a variant to impaired islet ß-cell function remains unclear. Firstly, a similar HNF1a-Q125ter variant in zebrafish (hnf1a+/-) was generated by CRISPR/Cas9. We further crossed hnf1a+/- with several zebrafish reporter lines to investigate pancreatic ß-cell function. Next, we introduced HNF1a-Q125ter and HNF1a shRNA plasmids into the Ins-1 cell line and elucidated the molecular mechanism. hnf1a+/- zebrafish significantly decreased the ß-cell number, insulin expression, and secretion. Moreover, ß cells in hnf1a+/- dilated ER lumen and increased the levels of ER stress markers. Similar ER-stress phenomena were observed in an HNF1a-Q125ter-transfected Ins-1 cell. Follow-up investigations demonstrated that HNF1a-Q125ter induced ER stress through activating the PERK/eIF2a/ATF4 signaling pathway. Our study found a novel loss-of-function HNF1a-Q125ter variant which induced ß-cell dysfunction by activating ER stress via the PERK/eIF2a/ATF4 signaling pathway.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Animais , Estresse do Retículo Endoplasmático/genética , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Células Secretoras de Insulina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Insulina/metabolismo
10.
BMC Gastroenterol ; 21(1): 431, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34794374

RESUMO

PURPOSE: The aim of the study is to explore the independent association of free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) with hepatic steatosis and insulin resistance. METHODS: A cross-sectional study of 88 overweight/obese adults who underwent anthropometric measurements [BMI, waist circumference (WC) and waist-to-height ratio (WHtR)], hepatic steatosis assessment (FibroScan) and thyroid-related hormones tests was conducted from 2018 to 2020 in Xiamen, China. RESULTS: Subjects with increasing tertiles of FT3 showed significantly higher levels of controlled attenuation parameter (CAP) ((295.4 ± 44.1, 290.1 ± 68.2 and 331.7 ± 43.6 (dB/m) for tertile 1-3, respectively, p = 0.007) and fatty liver index (FLI) score (47.7 (33.9-60.8), 61.5 (45.1-88.9) and 90.5 (84.5-94.8), respectively, p < 0.001). FT3 significantly and positively correlated with obesity index (BMI, WC, and WHtR), homeostatic model assessment of insulin resistance (HOMA-IR) and hepatic steatosis (CAP and FLI). Multivariable linear regression analyses with adjustment for potential confounding factors showed FT3 was independently associated with BMI (regression coefficient (ß (95%CI): 0.024 (0.004-0.043), p = 0.020), HOMA-IR (ß (95%CI): 0.091 (0.007-0.174), p = 0.034), CAP (ß (95%CI): 25.45 (2.59-48.31), p = 0.030) and FLI (ß (95%CI): 0.121 (0.049-0.194), p = 0.001). Neither FT4 nor TSH was significantly associated with any indicators of obesity, insulin resistance or hepatic steatosis. CONCLUSIONS: Increased FT3, but not FT4 or TSH, was independently associated with higher risks of hepatic steatosis and insulin resistance in euthyroid overweight/obese Chinese adults. Trial registration Registration is not applicable for our study.


Assuntos
Fígado Gorduroso , Resistência à Insulina , Adulto , China , Estudos Transversais , Humanos , Obesidade/complicações , Sobrepeso/complicações , Glândula Tireoide , Hormônios Tireóideos , Tireotropina , Tiroxina , Tri-Iodotironina
11.
Int J Obes (Lond) ; 44(10): 2044-2051, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32541918

RESUMO

OBJECTIVE: Animal studies and epidemiological studies have shown that there is potential sex-specific sensitivity to the intrauterine environment in relation to the developmental programming of obesity. The objective of this study was to assess the sex-specific association between prenatal antibiotics exposure and body mass index (BMI) in offspring from 1 to 4 years. METHODS: A total of 10,163 mother-child pairs from the Medical Birth Registry in Xiamen, China, were included in this prospective cohort study. Data on prenatal antibiotics exposure were collected from the prescription database. RESULTS: A total of 4909 (48.3%) offspring had prenatal antibiotics exposure. The associations between prenatal antibiotics exposure and offspring's BMI were significantly different among female offspring and male offspring (P for interaction: 0.034 at 1 year of age; 0.033 at 2 years of age; 0.020 at 3 years of age; and 0.021 at 4 years of age). In female offspring, prenatal antibiotic use was significantly associated with a higher BMI Z-score from 1 to 4 years old (difference in BMI Z-score: 0.11 [95% CI: 0.05-0.17] at 1 years of age; 0.10 [95% CI: 0.05-0.16] at 2 years of age; 0.14 [95% CI: 0.09-0.21] at 3 years of age; and 0.13 [95% CI: 0.07-0.19] at 4 years of age) after adjustment for confounder. Prenatal antibiotics use was not associated with offspring BMI Z-score from 1 to 4 years in male offspring. CONCLUSIONS: The association of prenatal antibiotics exposure and BMI Z-score from 1 to 4 years old may differ by sex of offspring.


Assuntos
Antibacterianos/administração & dosagem , Índice de Massa Corporal , Efeitos Tardios da Exposição Pré-Natal , Fatores Sexuais , Pré-Escolar , China , Feminino , Humanos , Masculino , Gravidez , Estudos Prospectivos
12.
BMC Pregnancy Childbirth ; 19(1): 138, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31023245

RESUMO

BACKGROUND: It has been reported that earlier age at menarche is associated with a higher risk for type 2 diabetes mellitus. However, the relationship between age at menarche and gestational diabetes mellitus is inconsistent across studies. We hypothesized that an earlier age at menarche would predict the gestational diabetes mellitus risk. METHODS: This was a population-based, retrospective cohort study of 70,041 women aged 18 to 53 years old, conducted between 2011 and 2018. The subjects were recruited from the Medical Birth Registry in Xiamen, China. Age at menarche was categorized as 8-12, 13, 14, 15, 16-19 years old. Logistic regression analysis and spline analysis was used to assess the risk of the menarche age group for gestational diabetes mellitus. Linear regression analysis was performed to evaluate independent associations between age at menarche and fasting plasma glucose and blood glucose 1 hour and 2 hours after a 75-g of glucose load between 24 and 28 weeks' gestation. RESULTS: The overall prevalence of GDM was 17.6%. After adjustment for family history of diabetes, earlier age at menarche (8-12, and 13 years old) was associated with increased odds for GDM (OR, 1.08; 95% CI, 1.02-1.15, and OR, 1.07; 95% CI, 1.03-1.14, respectively) compared with average age at menarche (14 years old). With further adjustment for pre-pregnancy body mass index, blood pressure, educational level, age at delivery, and hepatitis B surface antigen status, this association was attenuated (OR, 0.93, and OR, 1.02, respectively). Multivariable-adjusted spline regression models showed a linear dose-response association between age at menarche and GDM (P for nonlinearity, 0.203; P for linearity, 0.006). On linear regression analysis, earlier age at menarche was significantly associated with increased blood glucose one and 2 hours after a glucose load but not with the fasting plasma glucose. CONCLUSIONS: As expected, early age at menarche was found to be associated with an increased risk of gestational diabetes mellitus. However, this association may be mediated by potential confounding factors other than age. An additional finding was that earlier menarche was significantly related with elevated pregnancy glucose concentrations after a glucose load.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Gestacional/epidemiologia , Menarca , Adolescente , Adulto , Glicemia/análise , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
13.
Zhonghua Yi Xue Za Zhi ; 96(11): 897-900, 2016 Mar 22.
Artigo em Zh | MEDLINE | ID: mdl-27045655

RESUMO

OBJECTIVE: To evaluate the effects of lipopolysaccharide (LPS) and dexamethasone on function of hypothalamus-pituitary-testis axis and to explore the possible underlying mechanisms. METHODS: LPS (100 µg/kg), dexamethasone (DEX, 1 mg/kg) and phosphate buffer saline (PBS) were injected subcutaneously into castrated mice (n=5 in each group) for 4 weeks. The expression of Kisspeptin and its receptor GPR54 in hypothalamus were measured by immunohistochemistry, and plasma luteinizing hormone (LH) were measured by chemiluminescence immunoassay. RESULTS: After LPS and DEX were administered for 4 weeks, the LH level in LPS group and DEX group was (1.79±0.74) U/L and (2.19±0.60) U/L, respectively, which were lower than PBS group (4.87±1.25) U/L (all P<0.01). In LPS group, after treatment, the kisspeptin immunohistochemistry index in hypothalamus was 4.2±1.1, which was lower than the control group (10.2±1.6, P<0.05). The GPR54 immunohistochemistry index in hypothalamus was 3.6±0.5, which was lower than PBS group (6.2±1.8, P<0.05). In DEX group, the expressions of kisspeptin and GPR 54 in hypothalamus did not change after treatment. CONCLUSIONS: LPS may downregulate function of hypothalamus-pituitary-testis axis through Kisspeptin/GPR54 system. Dexamethasone could suppress function of gonadal axis as well, while the underlying mechanism is still unclear.


Assuntos
Dexametasona/farmacologia , Hipotálamo/metabolismo , Kisspeptinas/metabolismo , Lipopolissacarídeos/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Animais , Hipotálamo/efeitos dos fármacos , Imuno-Histoquímica , Hormônio Luteinizante/sangue , Masculino , Camundongos , Receptores de Kisspeptina-1
14.
Hum Reprod ; 30(9): 2031-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26141714

RESUMO

STUDY QUESTION: Do patients with congenital combined pituitary hormone deficiency (CCPHD) have different responses to gonadotrophin-induced spermatogenesis compared with those with idiopathic hypogonadotropic hypogonadism (IHH)? SUMMARY ANSWER: CCPHD patients have a better response to gonadotrophin therapy than IHH patients. WHAT IS KNOWN ALREADY: Gonadotrophins are effective in inducing spermatogenesis in patients with hypogonadotropic hypogonadism. DESIGN, SIZE AND DURATION: This retrospective cohort study included 75 patients, 53 of whom had IHH and 22 CCPHD. They were diagnosed, treated and followed up between January 2008 and December 2013. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Combined gonadotrophin therapy, consisting of human chorionic gonadotrophin and human menopausal gonadotrophin, was administered for 24 months. The success rate of spermatogenesis (≥1 sperm in ejaculate), serum total testosterone level, testicle size and sperm concentration during the treatment, as well as the first time sperm were detected in the ejaculate, were compared between the two diagnostic groups. All patients were treated in Peking Union Medical College Hospital. MAIN RESULTS AND THE ROLE OF CHANCE: Spermatogenesis was successfully induced in 85% of IHH patients and 100% of CCPHD patients after 24-month combined gonadotrophin treatment (P = 0.03). In comparison with IHH, CCPHD patients had larger mean testicle sizes during the gonadotrophin treatment at 6, 12, 18 and 24 months (all P < 0.05). The initial time for sperm appearance in IHH group (n = 45) and CCPHD group (n = 22) was 13.2 ± 5.9 versus 10.4 ± 3.8 months (P = 0.045). Generally, CCPHD patients had higher sperm counts [median (quartiles)] than IHH patients during the treatment, but the difference was only statistically significant at 12 months of treatment, 3.3 (1.8, 12.0) versus 1.0 (0.0, 4.6) million/ml, P = 0.001. There was a higher level of serum total testosterone [mean (SD)] in the CCPHD group than the IHH group (676 ± 245 versus 555 ± 209 ng/dl, P = 0.035). LIMITATIONS, REASONS FOR CAUTION: First, the inherent nature of a retrospective designed study was a main shortcoming. Secondly, pathological gene mutations in IHH and CCPHD patients should be further investigated. Clarification of the underlying mechanisms between cryptorchidism and mutated genes may provide more information for the divergent therapeutic responses between two groups. Only a minority of patients were actively seeking to have children so information about fertility is limited. WIDER IMPLICATIONS OF THE FINDINGS: CCPHD patients had a lower incidence of cryptorchidism and a better response to gonadotrophin therapy than IHH patients, reflecting multiple defects on the different levels of reproduction axis in IHH. Furthermore, growth hormone is not indispensable for spermatogenesis in CCPHD patients. STUDY FUNDING/COMPETING INTERESTS: The study was supported by Natural Science Foundation of China (No: 81100416). None of the authors has any conflicts of interest to declare.


Assuntos
Gonadotropina Coriônica/farmacologia , Hipogonadismo/tratamento farmacológico , Hipopituitarismo/tratamento farmacológico , Menotropinas/farmacologia , Avaliação de Resultados em Cuidados de Saúde , Substâncias para o Controle da Reprodução/farmacologia , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testosterona/sangue , Adolescente , Adulto , Contagem de Células , Gonadotropina Coriônica/administração & dosagem , Criptorquidismo/etiologia , Seguimentos , Humanos , Hipogonadismo/complicações , Hipopituitarismo/complicações , Hipopituitarismo/congênito , Masculino , Menotropinas/administração & dosagem , Substâncias para o Controle da Reprodução/administração & dosagem , Estudos Retrospectivos , Contagem de Espermatozoides , Adulto Jovem
15.
Zhonghua Yi Xue Za Zhi ; 95(20): 1568-71, 2015 May 26.
Artigo em Zh | MEDLINE | ID: mdl-26463603

RESUMO

OBJECTIVE: To compare the efficacies of pulsatile gonadotropin-releasing hormone (GnRH) versus human chorionic gonadotropin/human menopausal gonadotropin (HCG/HMG) for spermatogenesis in male idiopathic hypogonadotropic hypogonadism (IHH). METHODS: For this retrospective study, a total of 92 male IHH outpatients from May 2010 to October 2014 were recruited and categorized into GnRH (n = 40) and HCG/HMG (n = 52) groups. Each subject selected one specific therapy voluntarily. The gonadotropin levels were measured in the first week and monthly post-treatment in GnRH group. And serum total testosterone (TT), testicular volume (TV) and rate of spermatogenesis were observed monthly post-treatment in two groups. Spermatogenesis, TT and TV were compared between two groups. RESULTS: All IHH patients were treated for over 3 months. The median follow-up periods in GnRH and HCG/HMG groups was 8.2 (3.0-18.4) and 9.2 (3.0-18.6) months respectively (P = 0.413). In GnRH group, LH ((0.5 ± 0.6) vs (3.4 ± 2.4) U/L, P < 0.01) and FSH ((1.3 ± 1.1) vs (5.8 ± 3.8) U/L, P < 0.01) increased after 1-week treatment. In GnRH group, at the end of follow-up, TT ((1.0 ± 1.0) vs (7.4 ± 5.2) nmol/L, P < 0.01) and TV ((2.3 ± 1.5) vs (8.1 ± 4.0) ml, P < 0.01) significantly increased compared to baseline. In HCG/HMG group, TT ((0.8 ± 0.6) vs (14.4 ± 8.0) nmol/L, P < 0.01) and TV ((2.3 ± 2.1) vs (7.6 ± 4.2) ml, P < 0.01) significantly increased after therapy. The success rate of spermatogenesis was 50.0% (20/40) in GnRH group versus 28.8% (15/52) in HCG/HMG group (P = 0.038). GnRH group required a shorter treatment time for initial sperm appearance than HCG/HMG group ((6.5 ± 3.1) vs (10.8 ± 3.7) months, P = 0.001). CONCLUSION: Pulsatile GnRH requires a shorter time for initiation of spermatogenesis than gonadotropin therapy in IHH male patients.


Assuntos
Hipogonadismo , Espermatogênese , Gonadotropina Coriônica , Hormônio Liberador de Gonadotropina , Gonadotropinas , Humanos , Masculino , Pacientes Ambulatoriais , Estudos Retrospectivos , Testículo
16.
Zhonghua Yi Xue Za Zhi ; 95(42): 3432-5, 2015 Nov 10.
Artigo em Zh | MEDLINE | ID: mdl-26813133

RESUMO

OBJECTIVE: To investigate the therapeutic effect of pulsatile GnRH (gonadorelin) pump on female patients with idiopathic hypogonadotropic hypogonadism (IHH). METHODS: In this retrospective study, five female IHH patients were recruited. Patients were treated with pulsatile gonadorelin (10 µg per 90 min) via a pump for at least 12 weeks. Serum gonadotropins and sex steroid levels were measured, and menses were recorded. RESULTS: After one-week treatment, luteinizing hormone (LH) level increased from (2.2 ± 2.0) U/L to (5.4 ± 2.5) U/L (P=0.028), follicle-stimulating hormone(FSH) level increased from (3.7 ± 2.7) U/L to(6.3 ± 1.0) U/L (P=0.162), and estradiol (E2) level increased from (58 ± 13) pmol/L to (260 ± 97) pmol/L (P=0.011). Menstrual bleeding was observed in 4 patients after starting treatment for 35-55 days and two natural pregnancies were reported. No menstrual bleeding was reported in another patient. The frequency of pulsatile GnRH had to be adjusted according to endogenous GnRH secretion during the follicular phase of normal women and regular menses were induced. CONCLUSIONS: Pulsatile GnRH is effective in treating female IHH. A constant frequency of pulsatile GnRH is suitable for most of IHH patients. However, for those who failed to produce regular menses, adjusting pulsatile frequency to imitate the physiological rhythm of GnRH may be an alternative option.


Assuntos
Hipogonadismo , Estradiol , Feminino , Hormônio Foliculoestimulante , Hormônio Liberador de Gonadotropina , Gonadotropinas , Humanos , Precursores de Proteínas , Estudos Retrospectivos
17.
Zhonghua Nan Ke Xue ; 21(7): 587-92, 2015 Jul.
Artigo em Zh | MEDLINE | ID: mdl-26333218

RESUMO

OBJECTIVE: To investigate the effects of different concentrations of lipopolysaccharide (LPS), tumor necrosis factor α (TNFα), interleukin-6 (IL-6), dexamethasone (Dex), and insulin on the mRNA and protein expressions of GPR54 in the MCF7 cell line in vitro. METHODS: MCF7 breasr cancer cells were cultured and treated with different concentrations of LPS (10 and 20 µg/ml), TNFα (20 and 100 ng/ml), IL-6 (10 and 20 ng/ml), Dex (10(-6) and 10(-7) mol/L), and insulin (0.01 and 0.1 IU/L). Those treated with culture fluid only served as controls. The mRNA and protein expressions of GPR54 were measured by real-time PCR and Western blot, respectively, after 6, 24, 48, and 72 hours of treatment. RESULTS: Compared with the blank con- trol, LPS (10 and 20 µg/ml), TNFα (20 and 100 ng/ml), IL-6 (10 and 20 ng/ml), Dex (10(-6) and 10(-7) mol/L), and insulin (0.01 and 0.1 IU/L) significantly increased the expressions of GPR54 mRNA (P < 0.05) and protein (P < 0.05). CONCLUSION: LPS, TNFα, IL-6, Dex, and insulin evidently increase the expression of GPR54 in the MCF7 cell line, indicating their influence on the function of gonads by regulating the GPR54 level.


Assuntos
RNA Mensageiro/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Western Blotting , Dexametasona/administração & dosagem , Dexametasona/farmacologia , Glucocorticoides/administração & dosagem , Glucocorticoides/farmacologia , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacologia , Insulina/administração & dosagem , Insulina/farmacologia , Interleucina-6/administração & dosagem , Interleucina-6/farmacologia , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/farmacologia , Células MCF-7 , Reação em Cadeia da Polimerase em Tempo Real , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Receptores Acoplados a Proteínas G/genética , Receptores de Kisspeptina-1 , Fatores de Tempo , Fator de Necrose Tumoral alfa/administração & dosagem , Fator de Necrose Tumoral alfa/farmacologia
18.
Nat Commun ; 15(1): 7775, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237559

RESUMO

Actualizing efficient and sustainable environmental catalysis is essential in global water pollution control. The single-atom Fenton-like process, as a promising technique, suffers from reducing potential environmental impacts of single-atom catalysts (SACs) synthesis and modulating functionalized species beyond the first coordination shell. Herein, we devised a high-performance SAC possessing impressive Fenton-like reactivity and extended stability by constructing abundant intrinsic topological defects within carbon planes anchored with Fe-N4 sites. Coupling atomic Fe-N4 moieties and adjacent intrinsic defects provides potent synergistic interaction. Density functional theory calculations reveal that the intrinsic defects optimize the d-band electronic structure of neighboring Fe centers through long-range interactions, consequently boosting the intrinsic activity of Fe-N4 sites. Life cycle assessment and long-term steady operation at the device level indicate promising industrial-scale treatment capability for actual wastewater. This work emphasizes the feasibility of synergistic defect engineering for refining single-atom Fenton-like chemistry and inspires rational materials design toward sustainable environmental remediation.

19.
Endocrine ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39017833

RESUMO

PURPOSE: To investigate the association between blood pressure (BP) time in range (TIR) and composite cardiovascular outcomes in patients with primary aldosteronism (PA). METHODS: Between January 2019 and December 2021, 47 patients with PA were recruited from the First Affiliated Hospital of Xiamen University. Twenty-four-hour ambulatory BP monitoring (ABPM) and cardiovascular outcomes were assessed in all patients during the first diagnosis of PA. RESULTS: The mean age of the patients was 48.8 ± 11.4 years. Compared to PA without composite cardiovascular outcomes, the nighttime systolic BP TIR [31.2% (6.2%, 81.2%) vs. 11.5% (0.0%, 29.7%), p = 0.02] and defined daily dose (DDDs) of antihypertensive medication [2.0 (1.0, 2.8) vs. 1.0 (1.0, 2.0), p = 0.03] were lower in PA patients with composite cardiovascular outcomes, while higher glucose (5.0 ± 1.0 mmol/L vs. 5.9 ± 1.5 mmol/L) and prevalence of a history of alcohol intake was higher in PA patients with composite cardiovascular outcomes. There were no differences in age, sex, BMI, smoking, duration of hypertension, lipid levels, aldosteronism, clinic BP, 24-hour mean BP, daytime or nighttime BP, percentage of nocturnal SBP or DBP decline, 24-hour BP TIR, daytime BP TIR, or nighttime DBP TIR between the two groups. After adjusting for confounding factors, nighttime systolic BP TIR was significantly associated with composite cardiovascular outcomes (adjusted OR = 0.92 [95% CI 0.86, 0.99]) in multiple logistic regression analysis. CONCLUSION: Nighttime systolic BP TIR was significantly associated with composite cardiovascular outcomes in patients with PA.

20.
Adv Mater ; 36(35): e2405035, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38936842

RESUMO

Integration of solar cells and electrochromic windows offers crucial contributions to green buildings. Solar-charging zinc anode-based electrochromic devices (ZECDs) present opportunities for addressing the solar intermittency issue. However, the limited energy storage capacity of ZECDs results in wasted harnessing of solar energy as well as overcharging. Herein, spectral-selective dual-band ZECDs that continuously transport solar energy to indoor appliances by remotely controlling the repeated bleached-tinted cycles during the daytime, are reported. Hexagonal phase cesium-doped tungsten bronze (h-Cs0.32WO3, CWO) nanocrystals are adopted for dual-band ZECDs due to their independent control ability of near-infrared (NIR) and visible (VIS) light transmittance (∆T = 73.0%, 700 nm; ∆T = 83.7%, 1200 nm) and excellent cycling stability (0.8% optical contrast decay at 1200 nm after 10 000 cycles). The prototype device (i.e., CWO//Zn//CWO) delivers extraordinary thermal insulation capability, displaying a 10 °C difference between "bright" and "dark" modes. Furthermore, an Internet of Things (IoT) controller to control the NIR and VIS lights of the CWO//Zn//CWO window wirelessly with a smartphone, empowering the continuous discharging of the solar-charged window during the daytime remotely, is developed. Such windows represent an intriguing potential technology whose future impact on green buildings may be substantial.

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