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1.
Am J Hum Genet ; 108(3): 469-481, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33626338

RESUMO

Total fertilization failure (TFF) can occur during in vitro fertilization (IVF) treatments, even following intracytoplasmic sperm injection (ICSI). Various male or female factors could contribute to TFF. Increasing evidence suggested that genetic variations in PLCZ1, which encodes 1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase zeta-1 (PLCζ), is involved in oocyte activation and is a key male factor in TFF. In the present study, we explored the genetic variants in male individuals that led to TFF. A total of 54 couples with TFF or poor fertilization (fertilization rate < 20%) were screened, and 21 couples were determined to have a male infertility factor by the mouse oocyte activation test. Whole-exome sequencing of these 21 male individuals identified three homozygous pathogenic variants in ACTL9 (actin like 9) in three individuals. ACTL9 variations led to abnormal ultrastructure of the perinuclear theca (PT), and PLCζ was absent in the head and present in the neck of the mutant sperm, which contributed to failed normal calcium oscillations in oocytes and subsequent TFF. The key roles of ACTL9 in the PT structure and TFF after ICSI were further confirmed in an Actl9-mutated mouse model. Furthermore, assisted oocyte activation by calcium ionophore exposure successfully overcame TFF and achieved live births in a couple with an ACTL9 variant. These findings identified the role of ACTL9 in the PT structure and the correct localization of PLCζ. The results also provide a genetic marker and a therapeutic option for individuals who have undergone ICSI without successful fertilization.


Assuntos
Actinas/genética , Infertilidade Masculina/genética , Fosfoinositídeo Fosfolipase C/genética , Espermatozoides/metabolismo , Adulto , Animais , Feminino , Fertilização in vitro/efeitos adversos , Homozigoto , Humanos , Infertilidade Masculina/patologia , Masculino , Camundongos , Oócitos/crescimento & desenvolvimento , Injeções de Esperma Intracitoplásmicas , Espermatozoides/patologia , Falha de Tratamento
2.
Phys Chem Chem Phys ; 26(6): 5558-5568, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38284214

RESUMO

Rare base-pairs consists of guanine (G) paired with rare bases, such as 5-methylcytosine (5-meCyt), 5-hydroxymethylcytosine (5-hmCyt), 5-carboxylcytosine (5-caCyt), and 5-formylcytosine (5-fCyt), have become the focus of epigenetic research because they can be used as markers to detect some chronic diseases and cancers. However, the correlation detection of these rare base-pairs is limited, which in turn limits the development of diagnostic tests and devices. Herein, the interaction of rare base-pairs adsorbed on pure and B/N-doped γ-graphyne (γ-GY) nanosheets was explored using the density functional theory. The calculated adsorption energy showed that the system of rare base-pairs on B-doped γ-GY is more stable than that on pure γ-GY or N-doped γ-GY. Translocation time values indicate that rare base-pairs can be successfully distinguished as the difference in their translocation times is very large for pure and B/N-doped γ-GY nanosheets. Meanwhile, sensing response values illustrated that pure and B-doped γ-GY are the best for G-5-hmCyt adsorption, while the N-doped γ-GY is the best for G-Cyt adsorption. The findings indicate that translocation times and sensing response can be used as detection indexes for pure and B/N doped γ-GY, which will provide a new way for experimental scientists to develop the biosensor components.


Assuntos
Adsorção , Pareamento de Bases
3.
BMC Geriatr ; 24(1): 55, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216896

RESUMO

BACKGROUND: Numerous studies have demonstrated a positive correlation between diet quality and cognitive performance, indicating that improving diet quality may be beneficial in preventing cognitive decline in older adults. However, few study has investigated the causal relationship between diet quality and cognitive performance. The purpose of this study is to evaluate the causal effects of diet quality on cognitive performance in Chinese adults aged 55 years and older. Particularly, we utilize the Chinese Diet Quality Index (CHEI), a dietary assessment tool tailored for Chinese populations, as a proxy for older adults' diet quality. METHODS: Data were obtained from the China Health and Nutrition Survey (CHNS) ([Formula: see text], [Formula: see text]55 years old) conducted in 2004 and 2006. Cognitive function was tested by a subset of items from the Telephone Interview for Cognitive Status-Modified (TICS-m). Data on dietary intake was retrieved from three consecutive 24 hour recalls by participants and its quality was assessed by the 17-items Chinese Healthy Eating Index (CHEI). An Instrumental Variable technique was used to deal with the potential endogeneity of dietary quality. The instrumental variable used in our study is the community mean of CHEI. RESULTS: After adjusting for socio-demographic factors (age, gender, education, per capita household income), lifestyle habits (smoking, alcohol consumption, physical activity, BMI), and chronic diseases (hypertension, diabetes), our findings revealed that improving diet quality had a significant positive effect on cognitive performance ([Formula: see text]), particularly in females aged 55-65 years ([Formula: see text]) and females with primary education and below ([Formula: see text]). CONCLUSION: Our study suggests that improving diet quality and adhering to the Dietary Guidelines for Chinese may enhance cognitive performance in Chinese adults aged 55 years and older.


Assuntos
Dieta , Estado Nutricional , Feminino , Humanos , Idoso , Inquéritos Nutricionais , Dieta Saudável , Cognição , China/epidemiologia
4.
Langmuir ; 39(2): 739-749, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36596649

RESUMO

Polymeric ionic liquid (such as poly[ViEtIm]Br)-modified reduced graphene oxide (rGO), rGO-poly[ViEtIm]Br, was nominated as an open carrier to construct a degradation platform. The large specific surface of rGO together with the anion-exchange property of poly[ViEtIm]Br terminals led to the wide growth of heteropolyanions (like [PW12O40]3-, [PMo12O40]3-, and [SiW12O40]4-), thus assembling the integrated catalyst rGO-poly[ViEtIm][heteropolyanions]. The grafted poly[ViEtIm]Br provided an anchor point to interlink the polar heteropolyanions and the nonpolar rGO substrate, endowing this graphene-based catalyst with excellent dispersibility. The adequate exposure of heteropolyanions further promoted the decolorization capability during the degradation procedure. Morphology, structure, and properties of materials were confirmed and monitored via transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV-vis) spectroscopy, etc. rGO-poly[ViEtIm][PW12O40] was selected as the optimal catalyst with degradation efficiency toward methyl orange reaching 98.7% in 3 h. In addition, the excellent structural stability of the catalyst improved the decolorization efficiency, which reached 95% after recycling five times.

5.
Phys Chem Chem Phys ; 25(23): 15693-15701, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37272831

RESUMO

Liu et al. (Proc. Natl. Acad. Sci. U. S. A, 2019, 116, 24966-24971) showed that at an altitude of 0 km, the reaction of SO3 with CH3OH to form CH3OSO3H reduces the amount of H2SO4 produced by the hydrolysis of SO3 in regions polluted with CH3OH. However, the influence of the water molecule has not been fully considered yet, which will limit the accuracy of calculating the loss of SO3 in regions polluted with CH3OH. Here, the influence of water molecules on the SO3 + CH3OH reaction in the gas phase and at the air-water interface was comprehensively explored by using high-level quantum chemical calculations and Born-Oppenheimer molecular dynamics (BOMD) simulations. Quantum chemical calculations show that both pathways for the formation of CH3OSO3H and H2SO4 with water molecules have greatly lowered energy barriers compared to the naked SO3 + CH3OH reaction. The effective rate coefficients reveal that H2O-catalyzed CH3OSO3H formation (a favorable route for CH3OSO3H formation) can be competitive with H2O-assisted H2SO4 formation (a favorable process for H2SO4 formation) at high altitudes up to 15 km. BOMD simulations found that H2O-induced formation of the CH3OSO3-⋯H3O+ ion pair and CH3OH-assisted formation of HSO4- and H3O+ ions were observed at the droplet surface. These interfacial routes followed a loop-structure or chain reaction mechanism and proceeded on a picosecond time scale. These results will contribute to better understanding of SO3 losses in the polluted areas of CH3OH.

6.
Phys Chem Chem Phys ; 25(42): 28885-28894, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37853821

RESUMO

The products resulting from the reactions between atmospheric acids and SO3 have a catalytic effect on the formation of new particles in aerosols. However, the SO3 + HCl reaction in the gas-phase and at the air-water interface has not been considered. Herein, this reaction was explored exhaustively by using high-level quantum chemical calculations and Born Oppenheimer molecular dynamics (BOMD) simulations. The quantum calculations show that the gas-phase reaction of SO3 + HCl is highly unlikely to occur under atmospheric conditions with a high energy barrier of 22.6 kcal mol-1. H2O and (H2O)2 play obvious catalytic roles in reducing the energy barrier of the SO3 + HCl reaction by over 18.2 kcal mol-1. The atmospheric lifetimes of SO3 show that the (H2O)2-assisted reaction dominates over the H2O-assisted reaction within the altitude range of 0-5 km, whereas the H2O-assisted reaction is more favorable within an altitude range of 10-50 km. BOMD simulations show that H2O-induced formation of the ClSO3-⋯H3O+ ion pair and HCl-assisted formation of the HSO4-⋯H3O+ ion pair were identified at the air-water interface. These routes followed a stepwise reaction mechanism and proceeded at a picosecond time scale. Interestingly, the formed ClSO3H in the gas phase has a tendency to aggregate with sulfuric acids, ammonias, and water molecules to form stable clusters within 40 ns simulation time, while the interfacial ClSO3- and H3O+ can attract H2SO4, NH3, and HNO3 for particle formation from the gas phase to the water surface. Thus, this work will not only help in understanding the SO3 + HCl reaction driven by water molecules in the gas-phase and at the air-water interface, but it will also provide some potential routes of aerosol formation from the reaction between SO3 and inorganic acids.

7.
J Phys Chem A ; 127(42): 8935-8942, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37844321

RESUMO

NH2SO3H is an effective nucleation agent for the formation of atmospheric aerosols and cloud particles. So, the ammonolysis of SO3 to form NH2SO3H without and with neutral (H2O) and basic (NH3) trace gases has been extensively investigated. However, the acidic trace gas X (X = H2SO4 and CH3SO3H)-assisted ammonolysis of SO3 is still up for debate. In this work, a comprehensive theoretical investigation of X-assisted ammonolysis of SO3 and its reverse reaction (the isomerization of NH2SO3H to form SO3-···NH3+) was carried out in the gas phase and at the air-water interface. The gas-phase results show that X-assisted isomerization of NH2SO3H to form SO3-···NH3+ is more energetically and kinetically favorable than its reverse reaction and the isomerization of NH2SO3H in the presence of H2O and NH3. Such unexpected findings revealed that gas-phase NH2SO3H is highly reactive in the presence of acidic trace gas in contrast to the high stability of NH2SO3H in neutral and basic conditions. At the air-water interface, the X-assisted isomerization reaction of NH2SO3H involves multiple water molecules. The loop structure of the reaction center (X···NH2SO3H···3H2O) promotes the transfer of protons in the water molecules to form the SO3-···NH3+ ion pair, which can then interact with several interfacial water molecules to form ammonium bisulfate. These interfacial reaction channels follow a stepwise mechanism and proceed at the picosecond time-scale. The findings of this study will contribute to a better understanding of the atmospheric behavior of NH2SO3H in polluted acidic trace gases.

8.
Plant Dis ; 2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37807089

RESUMO

Konjac (Amorphophallus konjac) is a perennial herbaceous plant of the Araceae family, cultivated mainly in south-western China and used extensively for weight loss (Chua et al. 2010). In June 2022, leaf blight was detected on a 2,00 ha A. konjac plantation in Chenxi County, Huaihua City, Hunan Province. It infected almost 20% of the area under cultivation and tends to occur each year during warm, humid weather from May to July, causing significant economic losses to A. konjac production. There were small brown spots on the leaves which gradually spread to form irregular brown lesions. In severe cases the entire plant turned yellow and died. Nine samples were collected randomly from different plants in three plantation forests to isolate the pathogens. They were washed with sterile water and the lesions were excised. They were subsequently disinfected with 3% hydrogen peroxide for 30 s, 75% ethanol for 90 s and rinsed three times with sterile water. The cut sections were then placed on water agar plates and grown in the dark in a constant temperature incubator at 28℃ for 3-5 days, when mycelia grew they were transferred to potato dextrose agar medium and grown in the dark at 28℃ for 3-5 days. Eleven purified fungal isolates were obtained, ten of which looked like Fusarium (90.9% isolation rate), and three representative isolates (MY5, MY7 and MY9) were chosen for further study. The fungal colonies initially appeared white and gradually turnned dark red. Macroconidia were crescent-shaped, elongated, slightly curved and had 2 to 4 septations, with a predominance of 3 septations. They measured 15.540 to 42.083 × 2.760 to 4.558 µm (n=100). Microconidia were oval or pyriform, with a maximum of one septum and measured 6.135 to 24.990 × 2.158 to 4.412 µm (n=100). Two genetic regions, the translation elongation factor-1 (TEF1-α) and RNA polymerase II largest subunit (RPB1) genes, were amplified and sequenced to verify the identity of the fungus (Qiu et al. 2023). The universal primers TEF1-F/R, G2R/Fa were used for amplification and sequencing, and the sequences were submitted to GenBank (TEF1-α: OR545395, OR545397, OR545399; RPB1: OR545394, OR545396, OR545398). A joint phylogenetic tree of the two genes was constructed and analysis showed that the three isolates were significantly clustered with Fusarium tricinctum. Based on the results of morphological identification and phylogenetic tree analysis, the three isolates were identified as F. tricinctum. Pathogenicity tests were carried out on 12 uniformly growing leaf expansion stages of konjac plants,each inoculated with five young leaves. Mycelial blocks of 6 × 6 mm grown on PDA media for 5 days were placed on the surface of the leaves, while sterile PDA blocks were placed on the control plant. After 10 days of rearing the treated plants in a constant temperature chamber at 28°C and 90% relative humidity, the lesions appeared and the pathogens re-isolated from the diseased tissues had the same morphological characteristics as representative isolates. F. tricinctum has been shown to be the major pathogenic fungus causing leaf blight in wheat (Triticum aestivum L.) (Castañares et al. 2011) and orchardgrass (Dactylis glomerata L.) (Wu et al. 2020). To our knowledge, this is the first time in the world that F. tricinctum has been reported to cause leaf blight in A. konjac. This research could provide a foundation for future control of leaf blight disease.

9.
Molecules ; 28(14)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37513430

RESUMO

For the purpose of regulating the visible-light-driven photocatalytic properties of photocatalysts, we selected BiOBr as the research target and various routes were used. Herein, via the use of a hydrothermal method with various solvents, BiOBr particles with controllable morphology and photocatalytic activities are obtained. In particular, through changing the volume ratio of ethylene glycol (EG) to ethanol (EtOH), BiOBr compounds possess microspheres, in which samples synthesized by using EG:EtOH = 1:2 have the highest photocatalytic activity, and can completely decompose RhB under visible light irradiation within 14 min. Furthermore, we also used different volume ratios of EG and H2O reaction solvents to prepare BiOBr particles so as to further improve its pollutant removal ability. When the volume ratio of EG to H2O is 1:1, the synthesized BiOBr particles have the best photocatalytic activity, and RhB can be degraded in only 10 min upon visible light irradiation. Aside from the reaction solvent, the impact of sintering temperature on the photocatalytic properties of BiOBr particles is also explored, where its pollutant removal capacities are restrained due to the reduced specific surface area. Additionally, the visible-light-triggered photocatalytic mechanism of BiOBr particles is determined by h+, ·OH and ·O2- active species.

10.
J Environ Sci (China) ; 127: 308-319, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36522063

RESUMO

Given the high abundance of water in the atmosphere, the reaction of Criegee intermediates (CIs) with (H2O)2 is considered to be the predominant removal pathway for CIs. However, recent experimental findings reported that the reactions of CIs with organic acids and carbonyls are faster than expected. At the same time, the interface behavior between CIs and carbonyls has not been reported so far. Here, the gas-phase and air-water interface behavior between Criegee intermediates and HCHO were explored by adopting high-level quantum chemical calculations and Born-Oppenheimer molecular dynamics (BOMD) simulations. Quantum chemical calculations evidence that the gas-phase reactions of CIs + HCHO are submerged energy or low energy barriers processes. The rate ratios speculate that the HCHO could be not only a significant tropospheric scavenger of CIs, but also an inhibitor in the oxidizing ability of CIs on SOx in dry and highly polluted areas with abundant HCHO concentration. The reactions of CH2OO with HCHO at the droplet's surface follow a loop structure mechanism to produce i) SOZ (), ii) BHMP (HOCH2OOCH2OH), and iii) HMHP (HOCH2OOH). Considering the harsh reaction conditions between CIs and HCHO at the interface (i.e., the two molecules must be sufficiently close to each other), the hydration of CIs is still their main atmospheric loss pathway. These results could help us get a better interpretation of the underlying CIs-aldehydes chemical processes in the global polluted urban atmospheres.


Assuntos
Atmosfera , Água , Água/química , Atmosfera/química , Aldeídos
11.
Mol Hum Reprod ; 28(8)2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35863052

RESUMO

Teratozoospermia is a common factor associated with male infertility. However, teratozoospermia characterized by bubble-shaped acrosomes (BSAs) has not yet been identified in men and the causative genes are unknown. The present study is of a patient with severe teratozoospermia characterized by BSA and carrying a variant (c.1204G>A, p.Gly402Ser) of actin-like 7A (ACTL7A). For further verification, we generated an Actl7a-mutated mouse model (p.Gly407Ser) carrying an equivalent variant to that in the patient. We found that homozygous Actl7a-mutated (Actl7aMut/Mut) male mice were sterile, and all their sperm showed acrosomal abnormalities. We detected by transmission electron microscopy that during acrosomal biogenesis, the acrosome detaches from the nuclear membrane in Actl7aMut/Mut mice. Furthermore, mutant ACTL7A failed to attach to the acroplaxome and was discharged by cytoplasmic droplets, which led to the absence of ACTL7A in epididymal spermatozoa in mice. The mutant sperm failed to activate the oocyte, and sperm-borne oocyte activation factor phospholipase C zeta (PLCζ) discharge accompanied by ACTL7A was observed, leading to total fertilization failure (TFF). Immunoprecipitation followed by liquid chromatography-mass spectrometry showed that several differentially expressed proteins participate in acrosome assembly and actin filament organization. Furthermore, assisted oocyte activation by calcium ionophore exposure successfully overcame TFF in the couple with an ACTL7A pathogenic variant. Our study defined a novel phenotype of an acrosomal abnormality characterized by BSA, revealed the underlying mechanism of a pathogenic variant in ACTL7A and provided a genetic marker and potential therapeutic option for male infertility.


Assuntos
Infertilidade Masculina , Teratozoospermia , Acrossomo/metabolismo , Animais , Humanos , Infertilidade Masculina/patologia , Masculino , Camundongos , Sêmen , Espermatozoides/metabolismo , Teratozoospermia/genética , Teratozoospermia/metabolismo , Teratozoospermia/patologia
12.
Cell Commun Signal ; 20(1): 84, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35689269

RESUMO

BACKGROUND: Neonatal hypoxic-ischemic brain injury (HIE) is caused by perinatal asphyxia, which is associated with various confounding factors. Although studies on the pathogenesis and treatment of HIE have matured, sub-hypothermia is the only clinical treatment available for HIE. Previous evidence indicates that chlorogenic acid (CGA) exerts a potential neuroprotective effect on brain injury. However, the role of CGA on neonatal HI brain damage and the exact mechanism remains elusive. Here, we investigate the effects of CGA on HI models in vivo and in vitro and explore the underlying mechanism. METHODS: In the in vivo experiment, we ligated the left common carotid artery of 7-day-old rats and placed the rats in a hypoxic box for 2 h. We did not ligate the common carotid artery of the pups in the sham group since they did not have hypoxia. Brain atrophy and infarct size were evaluated by Nissl staining, HE staining and 2,3,5-triphenyltetrazolium chloride monohydrate (TTC) staining. Morris Water Maze test (MWM) was used to evaluate neurobehavioral disorders. Western-blotting and immunofluorescence were used to detect the cell signaling pathway. Malondialdehyde (MDA) content test, catalase (CAT) activity detection and Elisa Assay was used to detect levels of inflammation and oxidative stress. in vitro experiments were performed on isolated primary neurons. RESULT: In our study, pretreatment with CGA significantly decreased the infarct volume of neonatal rats after HI, alleviated brain edema, and improved tissue structure in vivo. Moreover, we used the Morris water maze to verify CGA's effects on enhancing the learning and cognitive ability and helping to maintain the long-term spatial memory after HI injury. However, Sirt1 inhibitor EX-527 partially reversed these therapeutic effects. CGA pretreatment inhibited neuronal apoptosis induced by HI by reducing inflammation and oxidative stress. The findings suggest that CGA potentially activates Sirt1 to regulate the Nrf2-NF-κB signaling pathway by forming complexes thereby protecting primary neurons from oxygen-glucose deprivation (OGD) damage. Also, CGA treatment significantly suppresses HI-induced proliferation of glial. CONCLUSION: Collectively, this study uncovered the underlying mechanism of CGA on neonatal HI brain damage. CGA holds promise as an effective neuroprotective agent to promote neonatal brain recovery from HI-induced injury. Video Abstract.


Assuntos
Lesões Encefálicas , Hipóxia-Isquemia Encefálica , Fármacos Neuroprotetores , Animais , Animais Recém-Nascidos , Encéfalo/metabolismo , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Ácido Clorogênico/metabolismo , Ácido Clorogênico/farmacologia , Ácido Clorogênico/uso terapêutico , Hipóxia-Isquemia Encefálica/complicações , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/metabolismo , Infarto/tratamento farmacológico , Infarto/metabolismo , Infarto/patologia , Inflamação/metabolismo , Isquemia/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Sirtuína 1/metabolismo
13.
Phys Chem Chem Phys ; 24(30): 18205-18216, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35866623

RESUMO

Herein, the reaction mechanisms and kinetics for the HO2 + SO3 → HOSO2 + 3O2 reaction catalyzed by a water monomer, a water dimer and small clusters of sulfuric acid have been studied theoretically by quantum chemical methods and the Master Equation/Rice-Ramsperger-Kassel-Marcus (ME/RRKM) rate calculations. The calculated results show that when H2O is introduced into the HO2 + SO3 reaction, it not only enhances the stability of the reactant complexes by 9.0 kcal mol-1 but also reduces the energy of the transition state by 8.7 kcal mol-1. As compared with H2O, catalysts (H2O)2, H2SO4, H2SO4⋯H2O and (H2SO4)2 are more effective energetically, which not only results from a higher binding energy of 21.3-26.0 kcal mol-1 for the reactant complexes but also from a reduction of the energy of the transition states by 8.6-17.2 kcal mol-1. Effective rate constant calculations show that, as compared with H2O, catalysts (H2O)2, H2SO4, H2SO4⋯H2O and (H2SO4)2 can never become more efficient catalysts within the altitude range of 0-15 km due to their relatively lower concentrations. Besides, at 0 km altitude, the enhancement factor for the H2O and (k'WD1/ktot) (H2O)2-assisted HO2 + SO3 reaction within the temperature range of 280-320 K was respectively calculated to be 0.31%-0.34% and 0.16%-0.27%, while the corresponding enhancement factor of H2O and (H2O)2 at higher altitudes of 5-15 km was respectively found only 0.002%-0.12% and 0.00001%-0.022%, indicating that the contributions of H2O and (H2O)2 are not apparent in the gas-phase reaction of HO2 with SO3 especially at higher altitude. Overall, the present work will give a new insight into how a water monomer, a water dimer and small clusters of sulfuric acid catalyze the HO2 + SO3 → HOSO2 + 3O2 reaction.

14.
Phys Chem Chem Phys ; 24(8): 4966-4977, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35141735

RESUMO

NH2SO3H can directly participate in H2SO4-(CH3)2NH-based cluster formation, and thereby substantially enhance the cluster formation rate. Herein, the reaction mechanisms and kinetics for the formation of NH2SO3H from the hydrolysis of HNSO2 without and with neutral (H2O, (H2O)2, and (H2O)3), basic (NH3 and CH3NH2), and acidic (HCOOH, H2SO4, H2SO4⋯H2O, and (H2SO4)2) catalysts were studied theoretically at the CCSD(T)-F12/cc-pVDZ-F12//M06-2X/6-311+G(2df,2pd) level. The calculated results showed that neutral, basic, and acidic catalysts decrease the energy barrier by over 18.1 kcal mol-1; meanwhile, the product formation of NH2SO3H was more strongly bonded to neutral, basic, and acidic catalysts than to the reactants HNSO2 and H2O. This reveals that the reported neutral, basic, and acidic catalysts promote the formation of NH2SO3H from the hydrolysis of HNSO2 both kinetically and thermodynamically. Kinetic calculations using the master equation showed that (H2O)2 (100% RH) dominate over the other catalysts within the range of 0-10 km altitudes and 230-320 K with its rate ratio larger by at least 2.98 times, whereas HCOOH (3.2 × 109 molecules cm-3) is the most favorable catalysts at 15 km altitude in the troposphere. Overall, the present results will provide a definitive example that neutral, basic, and acidic catalysts have important influences on atmospheric reactions.

15.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(3): 273-278, 2022 Mar 15.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-35351257

RESUMO

OBJECTIVES: To study the application value of metagenomic next-generation sequencing (mNGS) in children with severe infectious diseases. METHODS: An analysis was performed on the clinical data and laboratory test results of 29 children with severe infection who were admitted to the Second Affiliated Hospital of Wenzhou Medical University from June 2018 to December 2020. Conventional pathogen culture was performed for the 29 specimens (27 peripheral blood specimens and 2 pleural effusion specimens) from the 29 children, and mNGS pathogen detection was performed at the same time. RESULTS: Among the 29 children, 2 tested positive by conventional pathogen culture with 2 strains of pathogen, and the detection rate was 7% (2/29); however, 20 children tested positive by mNGS with 38 strains of pathogen, and the detection rate was 69% (20/29). The pathogen detection rate of mNGS was significantly higher than that of conventional pathogen culture (P<0.05), and mNGS could detect the viruses, fungi, and other special pathogens that conventional pathogen culture failed to detect, such as Orientia tsutsugamushi. The univariate analysis showed that gender, routine blood test results, C-reactive protein, procalcitonin, D-dimer, radiological findings, and whether antibiotics were used before admission did not affect the results of mNGS (P>0.05). CONCLUSIONS: Compared with conventional pathogen culture, mNGS is more sensitive for pathogen detection, with fewer interference factors. Therefore, it is a better pathogenic diagnosis method for severe infectious diseases in children.


Assuntos
Doenças Transmissíveis , Metagenômica , Antibacterianos , Criança , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Metagenômica/métodos , Sensibilidade e Especificidade
16.
Phys Chem Chem Phys ; 23(22): 12749-12760, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34041511

RESUMO

The hydrolysis reaction of CH2OO with water and water clusters is believed to be a dominant sink for the CH2OO intermediate in the atmosphere. However, the favorable route for the hydrolysis of CH2OO with water clusters is still unclear. Here global minimum searching using the Tsinghua Global Minimum program has been introduced to find the most stable geometry of the CH2OO(H2O)n (n = 1-4) complex firstly. Then, based on these stable complexes, favorable hydrolysis of CH2OO with (H2O)n (n = 1-4) has been investigated using the quantum chemical method of CCSD(T)-F12a/cc-pVDZ-F12//B3LYP/6-311+G(2d,2p) and canonical variational transition state theory with small curvature tunneling. The calculated results have revealed that, although the contribution of CH2OO + (H2O)2 is the most obvious in the hydrolysis of CH2OO with (H2O)n (n = 1-4), the hydrolysis of CH2OO with (H2O)3 is not negligible in atmospheric gas-phase chemistry as its rate is close to the rate of the CH2OO + H2O reaction. The calculated results also show that, in a clean atmosphere, the CH2OO + (H2O)n (n = 1-2) reaction competes well with the CH2OO + SO2 reaction at 298 K when the concentrations of (H2O)n (n = 1-2) range from 20% relative humidity (RH) to 100% RH, and SO2 is 2.46 × 1011 molecules per cm3. Meanwhile, when the RH is higher than 40%, it is a new prediction that the CH2OO + (H2O)3 reaction can also compete well with the CH2OO + SO2 reaction at 298 K. Besides, Born-Oppenheimer molecular dynamics simulation results show that all the favorable channels of the CH2OO + (H2O)n (n = 1-3) reaction cannot react on a time scale of 100 ps in the NVT simulation. However, the NVE simulation results show that the CH2OO + (H2O)3 reaction can be finished well at 8.5 ps, indicating that the gas phase reaction of CH2OO + (H2O)3 is not negligible in the atmosphere. Overall, the present results have provided a definitive example of how the favorable hydrolysis of important atmospheric species with (H2O)n (n = 1-4) takes place, which will stimulate one to consider the favorable hydrolysis of water and water clusters with other Criegee intermediates and other important atmospheric species.

17.
J Phys Chem A ; 125(12): 2642-2652, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33755485

RESUMO

The hydrolysis of CH2OO is not only a dominant sink for the CH2OO intermediate in the atmosphere but also a key process in the formation of aerosols. Herein, the reaction mechanism and kinetics for the hydrolysis of CH2OO catalyzed by the precursors of atmospheric aerosols, including H2SO4, H2SO4···H2O, and (H2SO4)2, have been studied theoretically at the CCSD(T)-F12a/cc-pVDZ-F12//B3LYP/6-311+G(2df,2pd) level. The calculated results show that the three catalysts decrease the energy barrier by over 10.3 kcal·mol-1; at the same time, the product formation of HOCH2OOH is more strongly bonded to the three catalysts than to the reactants CH2OO and H2O, revealing that small clusters of sulfuric acid promote the hydrolysis of CH2OO both kinetically and thermodynamically. Kinetic simulations show that the H2SO4-assisted reaction is more favorable than the H2SO4···H2O- (the pseudo-first-order rate constant being 27.9-11.5 times larger) and (H2SO4)2- (between 2.8 × 104 and 3.4 × 105 times larger) catalyzed reactions. Additionally, due to relatively lower concentration of H2SO4, the hydrolysis of CH2OO with H2SO4 cannot compete with the CH2OO + H2O or (H2O)2 reaction within the temperature range of 280-320 K, since its pseudo-first-order rate ratio is smaller by 4-7 or 6-8 orders of magnitude, respectively. However, the present results provide a good example of how small clusters of sulfuric acid catalyze the hydrolysis of an important atmospheric species.

18.
Proc Natl Acad Sci U S A ; 115(15): 3960-3965, 2018 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-29567866

RESUMO

In insects, juvenile hormone (JH) and the steroid hormone ecdysone have opposing effects on regulation of the larval-pupal transition. Although increasing evidence suggests that JH represses ecdysone biosynthesis during larval development, the mechanism underlying this repression is not well understood. Here, we demonstrate that the expression of the Krüppel homolog 1 (Kr-h1), a gene encoding a transcription factor that mediates JH signaling, in ecdysone-producing organ prothoracic gland (PG) represses ecdysone biosynthesis by directly inhibiting the transcription of steroidogenic enzymes in both Drosophila and Bombyx Application of a JH mimic on ex vivo cultured PGs from Drosophila and Bombyx larvae induces Kr-h1 expression and inhibits the transcription of steroidogenic enzymes. In addition, PG-specific knockdown of Drosophila Kr-h1 promotes-while overexpression hampers-ecdysone production and pupariation. We further find that Kr-h1 inhibits the transcription of steroidogenic enzymes by directly binding to their promoters to induce promoter DNA methylation. Finally, we show that Kr-h1 does not affect DNA replication in Drosophila PG cells and that the reduction of PG size mediated by Kr-h1 overexpression can be rescued by feeding ecdysone. Taken together, our data indicate direct and conserved Kr-h1 repression of insect ecdysone biosynthesis in response to JH stimulation, providing insights into mechanisms underlying the antagonistic roles of JH and ecdysone.


Assuntos
Bombyx/metabolismo , Drosophila/metabolismo , Ecdisona/biossíntese , Proteínas de Insetos/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Animais , Vias Biossintéticas , Bombyx/enzimologia , Bombyx/genética , Bombyx/crescimento & desenvolvimento , Metilação de DNA , Drosophila/enzimologia , Drosophila/genética , Drosophila/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Proteínas de Insetos/genética , Hormônios Juvenis/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Regiões Promotoras Genéticas , Pupa
20.
Clin Genet ; 97(2): 347-351, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31463947

RESUMO

Total fertilization failure (TFF), which is the failure of fertilization in all oocytes, occurs in 1%-3% of intracytoplasmic sperm injection (ICSI) cycles. However, the sperm-related factors that cause fertilization failure in humans are still largely unknown. Here, we identified three novel homozygous variations in the PLCZ1 gene in a recessive inheritance pattern in three consanguineous families, which all located in a key catalytic domain, and predicted to modify its secondary structure and thus impair its hydrolytic activity. Moreover, immunofluorescent staining revealed that PLCζ in mutant sperm exhibited abnormal localization patterns. ICSI-AOA resulted in an increased rate of normal fertilization compared with previous ICSI cycles (75.0% vs 2.2%, P < .001). In summary, we identified three novel homozygous variations in PLCZ1 that led to poor or failed fertilization that could be overcame by ICSI-AOA.


Assuntos
Fertilização in vitro , Fosfoinositídeo Fosfolipase C/genética , Espermatozoides/patologia , Adulto , Consanguinidade , Feminino , Homozigoto , Humanos , Masculino , Oócitos/metabolismo , Fosfoinositídeo Fosfolipase C/ultraestrutura , Estrutura Secundária de Proteína , Injeções de Esperma Intracitoplásmicas/métodos , Espermatozoides/metabolismo
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