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1.
Environ Sci Pollut Res Int ; 30(20): 57717-57727, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36971937

RESUMO

We examined the relationships between exposure to polycyclic aromatic hydrocarbons (PAH) metabolites and sex hormones in pre- and postmenopausal women from the 2013-2016 National Health and Nutrition Examination Survey. The study comprised 648 premenopausal and 370 postmenopausal women (aged 20 years or older) with comprehensive data on PAH metabolites and sex steroid hormones. To evaluate the correlations between individual or mixture of the PAH metabolites and sex hormones stratified by menopausal status, we used linear regression and Bayesian kernel machine regression (BKMR). After controlling for confounders, 1-Hydroxynaphthalene (1-NAP) was inversely associated with total testosterone (TT), and 1-NAP, 3-Hydroxyfluorene (3-FLU), and 2-Hydroxyfluorene (2-FLU) were inversely associated with estradiol (E2). 3-FLU was positively associated with sex hormone-binding globulin (SHBG) and TT/E2, whereas 1-NAP and 2-FLU were inversely associated with free androgen index (FAI). In the BKMR analyses, chemical combination concentrations at or above the 55th percentile were inversely connected to E2, TT, and FAI values but positively correlated with SHBG when compared with the matching 50th percentile. In addition, we only found that mixed exposure to PAHs was positively associated with TT and SHBG in premenopausal women. Exposure to PAH metabolites, either alone or as a mixture, was negatively associated with E2, TT, FAI, and TT/E2 but positively associated with SHBG. These associations were stronger among postmenopausal women.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Humanos , Feminino , Inquéritos Nutricionais , Teorema de Bayes , Hormônios Esteroides Gonadais , Testosterona , Menopausa
2.
Artigo em Inglês | MEDLINE | ID: mdl-35966726

RESUMO

Objective: The study aimed to explore the correlation of serum chemokine (C-C motif) ligand 21 (CCL21) and heat shock protein 90 (Hsp90) with preeclampsia (PE). Methods: Between June 2021 and June 2022, 50 pregnant women with PE were included in the PE group, and 50 healthy pregnant women were included in the control group. The serum levels of CCL21 and Hsp90 were compared between the two groups. Results: PE patients showed significantly higher levels of CCL21 and Hsp90 than healthy pregnant women (P < 0.05). Correlation analysis showed a positive correlation between CCL21 and Hsp90 levels (r > 0, (P < 0.05)). Binary logistic regression analysis suggested that high expression of CCL21 and Hsp90 were influencing factors for PE (OR >1, (P < 0.05)). The area under the receiver operating characteristic (AUC) curves of Hsp90 and CCL21 levels for predicting PE were 0.895 and 0.864, respectively, suggesting a good predictive value. Conclusion: Serum CCL21 and Hsp90 show great potential as disease markers for PE prediction. Further trials are, however, required prior to clinical promotion.

3.
Artigo em Inglês | MEDLINE | ID: mdl-35958932

RESUMO

Objective: The purpose of the study was to determine the significance of heat shock protein 90 (HSP 90) and serum chemokine ligand 21 (CCL-21) in pregnant women with preeclampsia (PE). Methods: From June 2021 to June 2022, the study enrolled 100 women undergoing obstetric examinations and delivering in our hospital; 50 PE patients undergoing routine obstetric examinations and delivering during the same period were enrolled in the research group; according to the severity, they were divided into mild PE and severe PE groups, while 50 healthy pregnant women undergoing obstetric examinations and delivering in our hospital during the same period were enrolled in the control group. In a subsequent analysis, serum levels of CCL-21 and HSP90 were compared between the two groups, and the correlation among CCL-21, HSP 90, and PE severity was analyzed. Results: An overall total of 50 patients with PE were enrolled in the study, which included 32 patients with mild PE and 18 patients with severe PE. Patients with severe PE had lower mean arterial pressure (MAP), HSP 90, and CCL21 index levels than those with mild PE; MAP, HSP 90, and CCL21 in the severe PE group were higher than those in the mild PE group, but the difference was not statistically significant; In the research group, MAP was weakly correlated with HSP90 concentration and CCL21 concentration, with correlation coefficients of 0.33 and 0.30, respectively, and the correlation analysis was significant. Conclusion: Patients with PE showed significantly increased serum concentrations of HSP90 and CCL-21, but a significant difference did not exist between mild and severe PE. In addition, there was a weak relationship between HSP90 and CCL-21 concentrations in PE patients and MAP, suggesting that HSP90 and CCL-21 play an instrumental role in the pathogenesis of PE, although more studies are needed to clarify the exact mechanisms.

4.
J Chem Phys ; 156(21): 214301, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35676157

RESUMO

The rotational state resolved photodissociation dynamics of D2O via the C̃(010) state has been investigated by using the D-atom Rydberg tagging time-of-flight technique combined with a tunable vacuum ultraviolet light source. The D-atom action spectrum of the C̃(010) ← X̃(000) band and the corresponding time-of-flight (TOF) spectra of D-atom photoproducts formed following the excitation of D2O to individual rotational transition have been measured. By comparison with the action spectrum of the C̃(000) ← X̃(000) band, the bending vibrational constant of the C̃ state for D2O can be determined to be v2 = 1041.37 ± 0.71 cm-1. From the TOF spectra, the product kinetic energy spectra, the vibrational state distributions of OD products, and the state resolved anisotropy parameters have been determined. The experimental results indicate a dramatic variation in the OD product state distributions for different rotational excitations. This illuminates that there are two distinctive coupling channels from the C̃(010) state to the low-lying electronic states: the homogeneous electronic coupling to the Ã1B1 state, resulting in vibrationally hot OD(X) products, and the Coriolis-type coupling to the B̃1A1 state, producing vibrationally cold but rotationally hot OD(X) and OD(A) products. Furthermore, the three-body dissociation channel is confirmed, which is attributed to the C̃ → 1A2 or C̃ → à pathway. In comparison with the previous results of D2O photolysis via the C̃(000) state, it is found that the v2 vibration of the parent molecule enhances both the vibrational and rotational excitations of OD products.

5.
J Chem Phys ; 156(5): 054302, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35135268

RESUMO

The vacuum ultraviolet (VUV) photodissociation of CO2 is important to understand the primary photochemical processes of CO2 induced by solar VUV excitation in the Earth's atmosphere. Here, we report a detailed study of vibrational-state-specific photodissociation dynamics of the CO(X1Σ+) + O(1D2) channel via the 3P1Πu state by using the time-sliced velocity-mapped ion imaging apparatus combined with the single VUV photoionization detection scheme. By recording the sliced images of the O(1D2) photoproducts formed by VUV photoexcitation of CO2 to the individual vibrational structure of the 3P1Πu state, both the vibrational state distributions of the counterpart CO(X1Σ+) photoproducts and the vibrational-state-specific product anisotropy parameters (ß) are determined. The experimental results show that photodissociation of CO2 at 108.22, 107.50, 106.10, and 104.76 nm yields less anisotropic (ß > 0) and inverted distributed CO(X1Σ+, v) photoproducts. The possible dissociation mechanism for the CO(X1Σ+) + O(1D2) channel may involve the non-adiabatic transition of excited CO2* from the initially prepared state to the 31A' state with potential energy barriers. While at 108.82 and 107.35 nm, the vibrational distributions are found to have the population peaked at a low vibrational state, and the anisotropy parameters turn out to be negative. Such variation indicates the possibility of another non-adiabatic dissociation pathway that may involve Coriolis-type coupling to the low-lying dissociative state. These observations show sclear evidence of the influence of the initially vibrational excitations on the photodissociation dynamics of CO2 via the 3P1Πu state.

6.
Nat Commun ; 12(1): 4459, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294710

RESUMO

The detailed features of molecular photochemistry are key to understanding chemical processes enabled by non-adiabatic transitions between potential energy surfaces. But even in a small molecule like hydrogen sulphide (H2S), the influence of non-adiabatic transitions is not yet well understood. Here we report high resolution translational spectroscopy measurements of the H and S(1D) photoproducts formed following excitation of H2S to selected quantum levels of a Rydberg state with 1B1 electronic symmetry at wavelengths λ ~ 139.1 nm, revealing rich photofragmentation dynamics. Analysis reveals formation of SH(X), SH(A), S(3P) and H2 co-fragments, and in the diatomic products, inverted internal state population distributions. These nuclear dynamics are rationalised in terms of vibronic and rotational dependent predissociations, with relative probabilities depending on the parent quantum level. The study suggests likely formation routes for the S atoms attributed to solar photolysis of H2S in the coma of comets like C/1995 O1 and C/2014 Q2.

7.
Sci Adv ; 7(30)2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34290097

RESUMO

The deuterium versus hydrogen (D/H) isotopic ratios are important to understand the source of water on Earth and other terrestrial planets. However, the determinations of D/H ratios suggest a hydrogen isotopic diversity in the planetary objects of the solar system. Photochemistry has been suggested as one source of this isotope heterogeneity. Here, we have revealed the photodissociation features of the water isotopologue (HOD) at λ = 120.8 to 121.7 nm. The results show different quantum state populations of OH and OD fragments from HOD photodissociation, suggesting strong isotope effect. The branching ratios of H + OD and D + OH channels display large isotopic fractionation, with ratios of 0.70 ± 0.10 at 121.08 nm and 0.49 ± 0.10 at 121.6 nm. Because water is abundant in the solar nebula, photodissociation of HOD should be an alternative source of the D/H isotope heterogeneity. This isotope effect must be considered in the photochemical models.

8.
FEBS Open Bio ; 11(8): 2266-2272, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34137203

RESUMO

Children show a distinct presentation of COVID-19, characterized by a lower incidence and mild phenotype, but the reason for this is still unknown. The angiotensin-converting enzyme 2 (ACE2) functions as the primary cell entry receptor for Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is thought to cause distinct clinical features between children and old people. The primary purpose of this study was to determine whether differences exist in the level of expression and distribution of ACE2 between neonatal and adult rat lungs. The lung tissues from rats of various ages were used to investigate the expression patterns of ACE2. Western blot, immunohistochemistry, and immunofluorescence were used to quantify or identify the localization of ACE2 in rat lungs. ACE2 was homogenously expressed in fewer alveolar type II (AT2) cells in the neonatal lung, with no polarization to the alveolar space and additional expression in pulmonary endothelium when compared to adult rat lungs. These findings suggest that the patterns of ACE2 distribution and cellular localization in rat lungs change with age.

9.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(1): 25-30, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33476533

RESUMO

OBJECTIVE: To study the influence of premature rupture of membranes (PROM) on the early prognosis of extremely premature infants, and to provide a basis for the management of extremely premature infants and prenatal consultation. METHODS: A total of 179 extremely premature singleton infants who were born from 2017 to 2019 were enrolled. According to the presence or absence of PROM, they were divided into two groups: PROM group (n=69) and non-PROM group (n=110). A statistical analysis was performed for maternal data and early prognostic indicators. RESULTS: Compared with the non-PROM group, the PROM group had significantly higher incidence rates of earlyonset sepsis and necrotizing enterocolitis (NEC) (P < 0.05) and significantly lower rate of use of pulmonary surfactant and incidence rate of hemodynamically significant patent ductus arteriosus (P < 0.05). The multivariate logistic regression analysis showed that chorioamnionitis was an independent risk factor for early-onset sepsis and NEC (OR=11.062 and 9.437 respectively, P < 0.05), and PROM was an independent protective factor against the use of pulmonary surfactant (OR=0.363, P < 0.05). CONCLUSIONS: PROM increases the incidence rates of early-onset sepsis and NEC in extremely premature infants and does not increase the incidence rates of other adverse outcomes. For pregnant women with PROM at the risk of extremely preterm delivery, prevention of miscarriage and chorioamnionitis is recommended to prolong gestational weeks, reduce the incidence rate of infection, and thus improve the outcome of extremely premature infants.


Assuntos
Corioamnionite , Ruptura Prematura de Membranas Fetais , Enterocolite Necrosante/epidemiologia , Enterocolite Necrosante/etiologia , Feminino , Ruptura Prematura de Membranas Fetais/epidemiologia , Idade Gestacional , Humanos , Lactente , Lactente Extremamente Prematuro , Recém-Nascido , Gravidez , Prognóstico
10.
Clin J Pain ; 34(7): 685-690, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29200017

RESUMO

OBJECTIVES: Trigeminal neuralgia (TN) is commonly seen in older persons and negatively influences their daily life. Although some research on the efficacy of TN drugs has been conducted, the optimal choice still remains uncertain. Therefore, this network meta-analysis (NMA) evaluated the efficacy and performance of 8 drugs with respect to TN. METHODS: All literature was retrieved from the PubMed and Embase electronic databases by jointly searching key terms. The only outcome was response rate, expressed as the odds ratio with 95% credible/confidence intervals. Both a pairwise meta-analysis and NMA were conducted. Heat plot and node splitting were computed to measure the consistency between direct and indirect evidence. In addition, surface under cumulative ranking curves were utilized to rank different drugs for treating TN. RESULTS: In total, 13 studies and 672 TN patients were included in this NMA. With regard to the primary endpoint response rate, only lidocaine (LDC), botulinum toxin type A (BTX-A), and carbamazepine (CBZ) had a statistical better performance than the placebo. According to the surface under cumulative ranking curves, LDC, BTX-A, and CBZ are the most effective drugs for treating patients with TN. CONCLUSIONS: Among the 8 drugs investigated, all exhibited a capacity to alleviate TN more than the placebo except for pimozide and proparacaine. Moreover, LDC, BTX-A, and CBZ stood out for their high efficacy and could be recommended as the primary choice of treatment for TN.


Assuntos
Neuralgia do Trigêmeo/tratamento farmacológico , Analgésicos/uso terapêutico , Humanos , Metanálise em Rede
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