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1.
J Biol Chem ; 299(12): 105440, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37949227

RESUMO

In enterobacteria such as Escherichia coli, the general stress response is mediated by σs, the stationary phase dissociable promoter specificity subunit of RNA polymerase. σs is degraded by ClpXP during active growth in a process dependent on the RssB adaptor, which is thought to be stimulated by the phosphorylation of a conserved aspartate in its N-terminal receiver domain. Here we present the crystal structure of full-length RssB bound to a beryllofluoride phosphomimic. Compared to the structure of RssB bound to the IraD anti-adaptor, our new RssB structure with bound beryllofluoride reveals conformational differences and coil-to-helix transitions in the C-terminal region of the RssB receiver domain and in the interdomain segmented helical linker. These are accompanied by masking of the α4-ß5-α5 (4-5-5) "signaling" face of the RssB receiver domain by its C-terminal domain. Critically, using hydrogen-deuterium exchange mass spectrometry, we identify σs-binding determinants on the 4-5-5 face, implying that this surface needs to be unmasked to effect an interdomain interface switch and enable full σs engagement and hand-off to ClpXP. In activated receiver domains, the 4-5-5 face is often the locus of intermolecular interactions, but its masking by intramolecular contacts upon phosphorylation is unusual, emphasizing that RssB is a response regulator that undergoes atypical regulation.


Assuntos
Proteínas de Ligação a DNA , Endopeptidase Clp , Proteínas de Escherichia coli , Escherichia coli , Proteólise , Fator sigma , Fatores de Transcrição , Cristalografia por Raios X , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Endopeptidase Clp/química , Endopeptidase Clp/metabolismo , Ativação Enzimática , Escherichia coli/química , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Espectrometria de Massa com Troca Hidrogênio-Deutério , Fosforilação , Domínios Proteicos , Fator sigma/química , Fator sigma/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
2.
Am J Epidemiol ; 193(6): 917-925, 2024 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-38400650

RESUMO

Few methods have been used to characterize repeatedly measured biomarkers of chemical mixtures. We applied latent profile analysis (LPA) to serum concentrations of 4 perfluoroalkyl and polyfluoroalkyl substances (PFAS) measured at 4 time points from gestation to age 12 years. We evaluated the relationships between profiles and z scores of height, body mass index, fat mass index, and lean body mass index at age 12 years (n = 218). We compared LPA findings with an alternative approach for cumulative PFAS mixtures using g-computation to estimate the effect of simultaneously increasing the area under the receiver operating characteristic curve (AUC) for all PFAS. We identified 2 profiles: a higher PFAS profile (35% of sample) and a lower PFAS profile (relative to each other), based on their average PFAS concentrations at all time points. The higher PFAS profile had generally lower z scores for all outcomes, with somewhat larger effects for males, though all 95% CIs crossed the null. For example, the higher PFAS profile was associated with a 0.50-unit lower (ß = -0.50; 95% CI, -1.07 to 0.08) BMI z score among males but not among females (ß = 0.04; 95% CI, -0.45 to 0.54). We observed similar patterns with AUCs. We found that a higher childhood PFAS profile and higher cumulative PFAS mixtures may be associated with altered growth in early adolescence. This article is part of a Special Collection on Environmental Epidemiology.


Assuntos
Composição Corporal , Índice de Massa Corporal , Exposição Ambiental , Fluorocarbonos , Humanos , Fluorocarbonos/sangue , Feminino , Masculino , Criança , Composição Corporal/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Estudos Longitudinais , Gravidez , Adolescente , Poluentes Ambientais/sangue , Ácidos Alcanossulfônicos/sangue , Caprilatos/sangue , Efeitos Tardios da Exposição Pré-Natal , Pré-Escolar
3.
Am Nat ; 203(1): 92-108, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38207138

RESUMO

AbstractIn chorusing species, conspecific interference exerts strong selection on signal form and timing to maximize conspicuousness and attractiveness within the signaling milieu. We investigated how túngara frog calling strategies were influenced by varied social environments and male phenotypes and how calling interactions influenced female preferences. When chorusing, túngara frog calls consist of a whine typically followed by one to three chucks. In experimental choruses we saw that as chorus size increased, calls increasingly had their chucks overlapped by the high-amplitude beginning section of other callers' whines. Playback experiments revealed that such overlap reduced the attractiveness of calls to females but that appending additional chucks mitigated this effect. Thus, more elaborate calls were preferred when calls suffered overlap, although they were not preferred when overlap was absent. In response to increasing risk of overlap in larger choruses, males increased call elaboration. However, males overwhelmingly produced two-chuck calls in even the largest choruses, despite our results suggesting that additional chucks would more effectively safeguard calls. Furthermore, aspects of male phenotypes predicted to limit call elaboration had negligible or uncertain effects, suggesting that other constraints are operating. These results highlight how complex interrelations among signal form, signaling interactions, and the social environment shape the evolution of communication in social species.


Assuntos
Comportamento Sexual Animal , Vocalização Animal , Animais , Feminino , Masculino , Vocalização Animal/fisiologia , Comportamento Sexual Animal/fisiologia , Anuros/fisiologia
4.
Biostatistics ; 24(3): 585-602, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34923588

RESUMO

The two-phase study design is a cost-efficient sampling strategy when certain data elements are expensive and, thus, can only be collected on a sub-sample of subjects. To date guidance on how best to allocate resources within the design has assumed that primary interest lies in estimating association parameters. When primary interest lies in the development and evaluation of a risk prediction tool, however, such guidance may, in fact, be detrimental. To resolve this, we propose a novel strategy for resource allocation based on oversampling cases and subjects who have more extreme risk estimates according to a preliminary model developed using fully observed predictors. Key to the proposed strategy is that it focuses on enhancing efficiency regarding estimation of measures of predictive accuracy, rather than on efficiency regarding association parameters which is the standard paradigm. Towards valid estimation and inference for accuracy measures using the resultant data, we extend an existing semiparametric maximum likelihood ethod for estimating odds ratio association parameters to accommodate the biased sampling scheme and data incompleteness. Motivated by our sampling design, we additionally propose a general post-stratification scheme for analyzing general two-phase data for estimating predictive accuracy measures. Through theoretical calculations and simulation studies, we show that the proposed sampling strategy and post-stratification scheme achieve the promised efficiency improvement. Finally, we apply the proposed methods to develop and evaluate a preliminary model for predicting the risk of hospital readmission after cardiac surgery using data from the Pennsylvania Health Care Cost Containment Council.


Assuntos
Projetos de Pesquisa , Humanos , Simulação por Computador , Probabilidade
5.
Magn Reson Med ; 92(4): 1404-1420, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38647191

RESUMO

PURPOSE: To investigate whether parallel imaging-imposed geometric coil constraints can be relaxed when using a deep learning (DL)-based image reconstruction method as opposed to a traditional non-DL method. THEORY AND METHODS: Traditional and DL-based MR image reconstruction approaches operate in fundamentally different ways: Traditional methods solve a system of equations derived from the image data whereas DL methods use data/target pairs to learn a generalizable reconstruction model. Two sets of head coil profiles were evaluated: (1) 8-channel and (2) 32-channel geometries. A DL model was compared to conjugate gradient SENSE (CG-SENSE) and L1-wavelet compressed sensing (CS) through quantitative metrics and visual assessment as coil overlap was increased. RESULTS: Results were generally consistent between experiments. As coil overlap increased, there was a significant (p < 0.001) decrease in performance in most cases for all methods. The decrease was most pronounced for CG-SENSE, and the DL models significantly outperformed (p < 0.001) their non-DL counterparts in all scenarios. CS showed improved robustness to coil overlap and signal-to-noise ratio (SNR) versus CG-SENSE, but had quantitatively and visually poorer reconstructions characterized by blurriness as compared to DL. DL showed virtually no change in performance across SNR and very small changes across coil overlap. CONCLUSION: The DL image reconstruction method produced images that were robust to coil overlap and of higher quality than CG-SENSE and CS. This suggests that geometric coil design constraints can be relaxed when using DL reconstruction methods.


Assuntos
Encéfalo , Aprendizado Profundo , Cabeça , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Razão Sinal-Ruído , Humanos , Imageamento por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem , Cabeça/diagnóstico por imagem , Algoritmos , Imagens de Fantasmas
6.
J Pediatr ; 266: 113878, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38135031

RESUMO

Current recommendations advise against blood transfusion in hemodynamically stable children with iron deficiency anemia. In an observational study of 125 children aged 6 through 36 months, hospitalized with iron deficiency anemia, we found that hemoglobin level predicted red blood cell transfusion (area under the curve 0.8862). A hemoglobin of 39 g/L had sensitivity 92% and specificity 72% for transfusion.


Assuntos
Anemia Ferropriva , Pré-Escolar , Humanos , Anemia Ferropriva/terapia , Transfusão de Sangue , Transfusão de Eritrócitos , Hemoglobinas/análise , Lactente
7.
J Exp Biol ; 227(2)2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38270203

RESUMO

The evolutionary origins of sexual preferences for chemical signals remain poorly understood, due, in part, to scant information on the molecules involved. In the current study, we identified a male pheromone in lake char (Salvelinus namaycush) to evaluate the hypothesis that it exploits a non-sexual preference for juvenile odour. In anadromous char species, the odour of stream-resident juveniles guides migratory adults into spawning streams. Lake char are also attracted to juvenile odour but have lost the anadromous phenotype and spawn on nearshore reefs, where juvenile odour does not persist long enough to act as a cue for spawning site selection by adults. Previous behavioural data raised the possibility that males release a pheromone that includes components of juvenile odour. Using metabolomics, we found that the most abundant molecule released by males was also released by juveniles but not females. Tandem mass spectrometry and nuclear magnetic resonance were used to identify the molecule as taurocholic acid (TCA), which was previously implicated as a component of juvenile odour. Additional chemical analyses revealed that males release TCA at high rates via their urine during the spawning season. Finally, picomolar concentrations of TCA attracted pre-spawning and spawning females but not males. Taken together, our results indicate that male lake char release TCA as a mating pheromone and support the hypothesis that the pheromone is a partial match of juvenile odour.


Assuntos
Truta , Animais , Feminino , Masculino , Feromônios , Reprodução , Ácido Taurocólico
8.
Biometrics ; 80(1)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38465982

RESUMO

In many modern machine learning applications, changes in covariate distributions and difficulty in acquiring outcome information have posed challenges to robust model training and evaluation. Numerous transfer learning methods have been developed to robustly adapt the model itself to some unlabeled target populations using existing labeled data in a source population. However, there is a paucity of literature on transferring performance metrics, especially receiver operating characteristic (ROC) parameters, of a trained model. In this paper, we aim to evaluate the performance of a trained binary classifier on unlabeled target population based on ROC analysis. We proposed Semisupervised Transfer lEarning of Accuracy Measures (STEAM), an efficient three-step estimation procedure that employs (1) double-index modeling to construct calibrated density ratio weights and (2) robust imputation to leverage the large amount of unlabeled data to improve estimation efficiency. We establish the consistency and asymptotic normality of the proposed estimator under the correct specification of either the density ratio model or the outcome model. We also correct for potential overfitting bias in the estimators in finite samples with cross-validation. We compare our proposed estimators to existing methods and show reductions in bias and gains in efficiency through simulations. We illustrate the practical utility of the proposed method on evaluating prediction performance of a phenotyping model for rheumatoid arthritis (RA) on a temporally evolving EHR cohort.


Assuntos
Aprendizado de Máquina , Aprendizado de Máquina Supervisionado , Humanos , Curva ROC , Projetos de Pesquisa , Viés
9.
Hepatol Res ; 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349813

RESUMO

AIM: This study aimed to establish the shear wave measurement (SWM) cut-off value for each fibrosis stage using magnetic resonance (MR) elastography values as a reference standard. METHODS: We prospectively analyzed 594 patients with chronic liver disease who underwent SWM and MR elastography. Correlation coefficients (were analyzed, and the diagnostic value was evaluated by the area under the receiver operating characteristic curve. Liver stiffness was categorized by MR elastography as F0 (<2.61 kPa), F1 (≥2.61 kPa, <2.97 kPa, any fibrosis), F2 (≥2.97 kPa, <3.62 kPa, significant fibrosis), F3 (≥3.62 kPa, <4.62 kPa, advanced fibrosis), or F4 (≥4.62 kPa, cirrhosis). RESULTS: The median SWM values increased significantly with increasing fibrosis stage (p < 0.001). The correlation coefficient between SWM and MR elastography values was 0.793 (95% confidence interval 0.761-0.821). The correlation coefficients between SWM and MR elastography values significantly decreased with increasing body mass index and skin-capsular distance; skin-capsular distance values were associated with significant differences in sensitivity, specificity, accuracy, or positive predictive value, whereas body mass index values were not. The best cut-off values for any fibrosis, significant fibrosis, advanced fibrosis, and cirrhosis were 6.18, 7.09, 8.05, and 10.89 kPa, respectively. CONCLUSIONS: This multicenter study in a large number of patients established SWM cut-off values for different degrees of fibrosis in chronic liver diseases using MR elastography as a reference standard. It is expected that these cut-off values will be applied to liver diseases in the future.

10.
Hepatol Res ; 54(7): 638-654, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38294946

RESUMO

AIM: This study aimed to evaluate the diagnostic performance of attenuation measurement (ATT; dual-frequency method) and improved algorithm of ATT (iATT; reference method) for the assessment of hepatic steatosis using magnetic resonance imaging (MRI)-derived proton density fat fraction (PDFF) as the reference standard. METHODS: We prospectively analyzed 427 patients with chronic liver disease who underwent ATT, iATT, or MRI-derived PDFF. Correlation coefficients were analyzed, and diagnostic values were evaluated by area under the receiver operating characteristic curve (AUROC). The steatosis grade was categorized as S0 (<5.2%), S1 (≥5.2%, <11.3%), S2 (≥11.3%, <17.1%), and S3 (≥17.1%) according to MRI-derived PDFF values. RESULTS: The median ATT and iATT values were 0.61 dB/cm/MHz (interquartile range 0.55-0.67 dB/cm/MHz) and 0.66 dB/cm/MHz (interquartile range 0.57-0.77 dB/cm/MHz). ATT and iATT values increased significantly as the steatosis grade increased in the order S0, S1, S2, and S3 (p < 0.001). The correlation coefficients between ATT or iATT values and MRI-derived PDFF values were 0.533 (95% confidence interval [CI] 0.477-0.610) and 0.803 (95% CI 0.766-0.834), with a significant difference between them (p < 0.001). For the detection of hepatic steatosis of ≥S1, ≥S2, and ≥S3, iATT yielded AUROCs of 0.926 (95% CI 0.901-0.951), 0.913 (95% CI 0.885-0.941), and 0.902 (95% CI 0.869-0.935), with significantly higher AUROC values than for ATT (p < 0.001, p < 0.001, p = 0.001). CONCLUSION: iATT showed excellent diagnostic performance for hepatic steatosis, and was strongly correlated with MRI-derived PDFF, with AUROCs of ≥0.900.

11.
Philos Trans A Math Phys Eng Sci ; 382(2276): 20230181, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-38945163

RESUMO

Intraplate earthquakes induced by anthropogenic fluid injection present unexpected seismic risk to previously quiescent or low seismicity-rate regions. Despite many studies of induced seismicity, there are relatively few with detailed openly accessible constraints on the interaction between seismic sources and subsurface structures. In this study of the Raton Basin, we refine source observations from a dense nodal array and constrain basin structure using teleseismic receiver functions. The cross-correlation-based relocated hypocentres and a new set of focal mechanisms light up active fault segments and show clear spatiotemporal patterns. The geometric complexity of reactivated fault clusters appears greatest near higher rate injection wells. Simpler normal fault structure is found farther from injection wells and near abrupt structural transitions suggested by receiver functions. While less induced seismicity in the crystalline basement is expected when injection is >1 km from the top of the basement (like Raton), our receiver function analysis identified a basin thickness ~3 km beneath the nodal array and lateral variations in sedimentary structures. Our results explain potential fluid connectivity between the injection depths focused at ~1-1.5 km below the surface and basement fault activity that begins at ~3 km and reaches peak activity at ~4-8 km depths. This article is part of the theme issue 'Induced seismicity in coupled subsurface systems'.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38866612

RESUMO

BACKGROUND AND AIMS: Few researchers have compared the effectiveness of traditional and novel obesity indicators in predicting stroke incidence. We aimed to evaluate the associations between six obesity indices and stroke risk, and to further identify the optimal indicator. METHODS AND RESULTS: A total of 14,539 individuals from the Rural Chinese Cohort Study were included in the analyses. We used the Cox proportional hazards regression models to evaluate the association between six obesity indices (including body mass index [BMI], waist circumference [WC], conicity index [C-index], lipid accumulation product [LAP], visceral adiposity index [VAI], and Chinese visceral adiposity index [CVAI]) and stroke risk. Receiver operating characteristic curves were employed to compare their predictive ability on stroke risk. During a median follow-up period of 11.13 years, a total of 1257 cases of stroke occurred. In the multiple-adjusted Cox regression model, WC, BMI, C-index, and CVAI were positively associated with ischemic stroke (P < 0.01) rather than hemorrhagic stroke risk. Dose-response analyses showed a linear correlation of WC, BMI, C-index, and LAP (Poverall <0.05, and Pnonlinear >0.05), but a non-linear correlation of CVAI (Poverall <0.05, and Pnonlinear <0.05) with the risk of ischemic stroke. CVAI demonstrates the highest areas under the curves (AUC: 0.661, 95% CI: 0.653-0.668), indicating a superior predictive ability for ischemic stroke occurrence compared to other five indices (P < 0.001). CONCLUSION: WC, BMI, C-index, LAP, and CVAI were all positively related to the risk of ischemic stroke, among which CVAI exhibited stronger predictive ability for ischemic stroke.

13.
Artigo em Inglês | MEDLINE | ID: mdl-39079837

RESUMO

BACKGROUND AND AIMS: This study aims to investigate the association of Chinese visceral adiposity index (CVAI) with incident hyperuricemia (HUA). METHODS AND RESULTS: We included 5186 adults aged ≥45 years from China Health and Retirement Longitudinal Study. Modified Poisson regression model was used to estimate the relative risks (RRs) of incident HUA associated with baseline CVAI, and logistic model was used to estimate the odds ratios (ORs) of HUA for CVAI change. Restricted cubic splines analysis was adopted to model the dose-response associations. The area under the receiver operating characteristic curve (AUC) analysis was used to evaluate the predictive value of CVAI. During 4-year follow-up, a total of 510 (9.8%) HUA cases were identified. The RRs (95%CIs) of incident HUA were 3.75 (2.85-4.93) for quartile 4 versus quartile 1 and 1.56 (1.45-1.69) for per-standard deviation increase in baseline CVAI. For the analyses of CVAI change, compared with stable group, participants in decreased group had 34% lower risk (OR 0.66, 95%CI 0.49-0.87) and those in increased group had 35% (1.35, 1.03-1.78) higher risk of HUA. Linear associations of baseline CVAI and its change with HUA were observed (Pnonlinear >0.05). Besides, the AUC value for HUA was 0.654 (0.629-0.679), which was higher than other five obesity indices. CONCLUSIONS: Our study found linear associations between baseline CVAI and its change and risk of HUA. CVAI had the best predictive performance in predicting incident HUA. These findings suggest CVAI as a reliable obesity index to identify individuals with higher HUA risk.

14.
BMC Pregnancy Childbirth ; 24(1): 474, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992621

RESUMO

PURPOSE: To identify which non-invasive infection indicators could better predict post-cervical cerclage (CC) infections, and on which days after CC infection indicators should be closely monitored. METHODS: The retrospective, single-center study included 619 single-pregnancy patients from January 2021 to December 2022. Patients were categorized into infected and uninfected groups based on physicians' judgments of post-CC infections. Registered information included patient characteristics, cervical insufficiency history, gestational age at CC, surgical method (McDonald/Shirodkar), purpose of CC, mid-pregnancy miscarriage/preterm birth, infection history or risk factors, and infection indices on days 1, 3, 5, and 7 after CC. Propensity score matching (PSM) was applied to reduce patient characteristic bias. Statistical analysis of C-reactive protein (CRP), white blood cell (WBC), neutrophil count (NEU), percentage of neutrophil count (NEU_P), interleukin-6 (IL-6), and procalcitonin (PCT) in the infected group compared with the uninfected group was performed using chi-square tests and t-tests. Receiver operating characteristic (ROC) curves were used to further assess the diagnostic value of CRP, PCT, and CRP-PCT in combination. RESULTS: Among the 619 included patients, 206 patients were matched using PSM and subsequently assessed. PCT values on day 1 and day 3 after CC exhibited significant differences between the two groups in two statistical ways (P < 0.01, P < 0.05). The CRP levels on day 1 were significantly higher in the infected group compared to the uninfected group in two statistical ways (P < 0.05). On day 3, the mean CRP value was significantly elevated in the infected group compared to the uninfected group (P < 0.05). Analyses of IL-6, WBC, NEU, and NEU_P did not yield clinically significant results. The area under the ROC curves for CRP, PCT, and CRP-PCT on day 1 and day 3 were all below 0.7. In the preventive CC group, the AUC values of CRP and CRP-PCT obtained on d1 were found to be higher than 0.7, indicating moderate diagnostic accuracy. CONCLUSION: For women after CC surgery, especially of preventive aim, increased serum CRP and PCT levels from post-CC day 1 to day 3 may signal a potential postoperative infection, warranting close monitoring.


Assuntos
Proteína C-Reativa , Cerclagem Cervical , Pró-Calcitonina , Humanos , Feminino , Proteína C-Reativa/análise , Estudos Retrospectivos , Pró-Calcitonina/sangue , Estudos de Casos e Controles , Gravidez , Adulto , Biomarcadores/sangue , Curva ROC , Incompetência do Colo do Útero/cirurgia , Incompetência do Colo do Útero/sangue , Valor Preditivo dos Testes , Contagem de Leucócitos , Interleucina-6/sangue , Fatores de Tempo
15.
BMC Pregnancy Childbirth ; 24(1): 10, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166739

RESUMO

BACKGROUND: Accurate prenatal recognition of discordant fetal growth in twins is critical for deciding suitable management strategies. We explored the predictive value of the level of maternal second-trimester placental growth factor (PLGF) as a novel indicator of discordant fetal growth. METHODS: A total of 860 women pregnant with twins were enrolled, including 168 women with monochorionic twins (31 cases of discordant fetal growth and 137 without) and 692 with dichorionic twins (79 cases of discordant fetal growth and 613 without). Maternal second-trimester PLGF concentrations were measured via immunofluorescence. RESULTS: Maternal second-trimester PLGF levels were significantly lower in women pregnant with twins who subsequently developed discordant fetal growth than in those who did not (monochorionic twin pregnancy: P < 0.001; dichorionic twin pregnancy: P < 0.001). A 3-4 fold difference in median PLGF concentrations was detected between the two groups with both monochorionic and dichorionic twin pregnancies. Maternal second-trimester PLGF levels were significantly correlated with birth weight differences (monochorionic twin pregnancy: r = - 0.331, P < 0.001; dichorionic twin pregnancy: r = - 0.234, P < 0.001). A receiver operating characteristic curve was used to evaluate the predictive efficiency. In monochorionic twin pregnancies, the area under the curve (AUC) was 0.751 (95% confidence interval [CI]: 0.649-0.852), and the cutoff value was 187.5 pg/mL with a sensitivity of 77.4% and specificity of 71.0%. In dichorionic twin pregnancies, the AUC was 0.716 (95% CI; 0.655-0.777), and the cutoff value was 252.5 pg/mL with a sensitivity of 65.1% and specificity of 69.6%. Based on the above cutoff values, univariate and multivariate logistic regression analyses were performed to calculate the odds ratios (OR) for the PLGF levels. After adjustment for potential confounding factors, low PLGF concentrations still significantly increased the risk of discordant fetal growth (monochorionic twin pregnancy: adjusted OR: 7.039, 95% CI: 2.798-17.710, P < 0.001; dichorionic twin pregnancy: adjusted OR: 4.279, 95% CI: 2.572-7.120, P < 0.001). CONCLUSIONS: A low maternal second-trimester PLGF level is considered a remarkable risk factor and potential predictor of discordant fetal growth. This finding provides a complementary screening strategy for the prediction of discordant fetal growth and offers a unique perspective for the subsequent research in this field.


Assuntos
Desenvolvimento Fetal , Fator de Crescimento Placentário , Gêmeos Dizigóticos , Feminino , Humanos , Gravidez , Fator de Crescimento Placentário/sangue , Fator de Crescimento Placentário/química , Gravidez de Gêmeos , Estudos Retrospectivos
16.
Neurol Sci ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780854

RESUMO

OBJECTIVE: This study aimed to assess the diagnostic potential of the Antibody concentration ratio in identifying treatment-refractory myasthenia gravis (MG). METHODS: A retrospective analysis was conducted on 116 MG patients who underwent antibody detection at least twice between June 1, 2015, and June 1, 2023. Demographic and clinical characteristics were collated to ascertain their association with refractory MG. The Antibody Concentration Ratio was applied to determine treatment response, using the International Consensus Guidance criteria as the reference standard. The area under nonparametric receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy were calculated to assess the diagnostic efficacy of the Antibody concentration ratio following consecutive immunotherapy relative to initial antibody concentrations for refractory MG. RESULTS: 19 out of 116 patients were unequivocally diagnosed with refractory MG. A significant correlation was found between the Antibody Concentration Ratio and refractory MG status in treatment-refractory and treatment-responsive patients. Subsequently, the AUC demonstrated the robust diagnostic capability of the Antibody concentration ratio for refractory MG, with an AUC of 0.8709 (95% CI: 0.7995-0.9422, p < 0.0001). The optimal cut-off value stood at 0.8903, exhibiting a sensitivity of 94.74% (95% CI: 75.36%-99.73%), a specificity of 68.04% (95% CI: 58.23%-76.48%), and accuracy of 72.41% (95% CI: 64.28%-80.54%). CONCLUSION: Elevated Antibody Concentration Ratio is intrinsically linked with refractory MG and exhibits potential as an diagnostic biomarker for the condition.

17.
Graefes Arch Clin Exp Ophthalmol ; 262(6): 1919-1924, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38294512

RESUMO

PURPOSE: Dysthyroid optic neuropathy (DON) leads to vision loss. This study aimed to investigate a new method that can directly evaluate the change in muscle cone inner volume (MCIV) and distinguish DON orbits from non-DONs. MATERIALS AND METHODS: This study included 54 patients (108 orbits) who were diagnosed with thyroid eye disease and treated at the Beijing Tongren Hospital between December 2019 and September 2021. The extraocular muscle volume (EOMV), orbital fat volume (OFV), and bony orbit volume (BOV) of the patients were measured using three-dimensional reconstruction. MCIV was measured using artificially defined boundaries. The associations between these volumes and clinical indicators were studied, and the diagnostic efficacy of these volumes for DON was described using receiver operating characteristic (ROC) curves. RESULTS: The ROC curve showed that the area under the curve of MCIV/BOV (%) combined with EOMV/BOV (%) reached 0.862 (p < 0.001), with a sensitivity of 85.7% and a specificity of 76.1%. CONCLUSION: The combination of MCIV/BOV (%) and EOMV/BOV (%) is a good indicator for the diagnosis of DON, which aids in the early detection and intervention of DON.


Assuntos
Oftalmopatia de Graves , Imageamento Tridimensional , Músculos Oculomotores , Doenças do Nervo Óptico , Órbita , Curva ROC , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Oftalmopatia de Graves/diagnóstico , Oftalmopatia de Graves/cirurgia , Doenças do Nervo Óptico/diagnóstico , Órbita/diagnóstico por imagem , Estudos Retrospectivos , Músculos Oculomotores/cirurgia , Músculos Oculomotores/fisiopatologia , Adulto , Idoso , Tomografia Computadorizada por Raios X/métodos
18.
Lipids Health Dis ; 23(1): 133, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38705980

RESUMO

BACKGROUND: Certain studies have indicated a link between obstructive sleep apnea and insulin resistance in specific populations. To gain more clarity, extensive research involving a broad sample of the overall population is essential. The primary objective of this study was to investigate this correlation by utilizing data from the National Health and Nutrition Examination Survey database. METHODS: The analysis incorporated data from the National Health and Nutrition Examination Survey database spanning the time periods from 2005 to 2008 and from 2015 to 2018, with a focus on American adults aged 18 years and older after applying weight adjustments. Key variables such as obstructive sleep apnea, triglyceride glucose index, and various confounding factors were considered. A generalized linear logistic regression model was used to investigate the association between obstructive sleep apnea and the triglyceride glucose index, with additional exploration of the consistency of the results through hierarchical analysis and other techniques. RESULTS: The study included participants aged between 18 and 90 years, with an average age of 46.75 years. Among the total sample, 50.76% were male. The triglyceride glucose index demonstrated a diagnostic capability for obstructive sleep apnea, with an AUC of 0.701 (95% CI: 0.6619-0.688). According to the fully adjusted model, individuals in the fourth quartile of the triglyceride glucose index showed an increased likelihood of having obstructive sleep apnea compared to those in the first quartile (OR: 1.45; 95% CI: 1.02-2.06; P < 0.05). Subgroup analysis indicated that male sex (OR: 2.09; 95% CI: 1.76-2.45; P < 0.05), younger age (OR: 2.83; 95% CI: 2.02-3.96; P < 0.05), white ethnicity (OR: 2.29; 95% CI: 1.93-2.73; P < 0.05), and obesity (OR: 1.54; 95% CI: 1.28-1.85; P < 0.05) were correlated with an elevated risk of OSA. CONCLUSIONS: This study demonstrated a strong association between an elevated TG index and OSA. Additionally, the triglyceride glucose index could serve as an independent predictor of obstructive sleep apnea.


Assuntos
Glicemia , Inquéritos Nutricionais , Apneia Obstrutiva do Sono , Triglicerídeos , Humanos , Apneia Obstrutiva do Sono/sangue , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue , Feminino , Adulto , Glicemia/metabolismo , Idoso , Adolescente , Adulto Jovem , Idoso de 80 Anos ou mais , Resistência à Insulina , Modelos Logísticos
19.
Lipids Health Dis ; 23(1): 141, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760825

RESUMO

BACKGROUND AND AIMS: Evidence from prospective cohort studies on the relationship between metabolic dysfunction-associated steatotic liver disease (MASLD) and longitudinal changes in serum ferritin (SF) still limited. This study aimed to investigate the associations of SF baselines and trajectories with new-onset MASLD and to present a MASLD discriminant model. METHODS: A total of 1895 participants who attended health examinations at least three times in a hospital in Dalian City between 2015 and 2022 were included. The main outcome was the incidence of MASLD. The associations between SF baselines and trajectories with the risk of MASLD were analyzed by Cox proportional hazards regression, restricted cubic spline (RCS) analysis and time-dependent receiver operating characteristic (ROC) curve analysis. In addition, a MASLD discrimination model was established using logistic regression analyses. RESULTS: Among the 1895 participants, 492 developed MASLD during follow-up. Kaplan-Meier analysis indicated that participants in the low-stable trajectory group had a longer MASLD-free time compared with participants in other groups. Compared with those in the low-stable trajectory group, the adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for the risk of new-onset MASLD in the medium-high, high-stable and high-high trajectory groups were 1.54(1.18-2.00), 1.77(1.35-2.32) and 1.55(1.07-2.26), respectively (Ptrend < 0.001). The results were robust in subgroup and sensitivity analyses. Multivariate Cox proportional regression showed that SF was an independent risk factor of MASLD (HR = 1.002, 95%CI: 1.000-1.003, P = 0.003). The restricted cubic spline demonstrated a nonlinear relationship between SF and the risk of MASLD. The 8-variable model had high discriminative performance, good accuracy and clinical effectiveness. The ROC curve results showed that AUC was greater than that of the FLI, HSI and ZJU models (all P < 0.01). CONCLUSIONS: Not only a higher baseline SF but also SF changing trajectory are significantly associated with risk of new-onset MASLD. SF could be a predictor of the occurrence of MASLD.


Assuntos
Ferritinas , Humanos , Ferritinas/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Incidência , Fatores de Risco , Adulto , Curva ROC , Modelos de Riscos Proporcionais , Estimativa de Kaplan-Meier , Fígado Gorduroso/sangue , Fígado Gorduroso/epidemiologia , Idoso , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/epidemiologia
20.
Sleep Breath ; 28(3): 1145-1153, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38180681

RESUMO

OBJECTIVE: To identify standard clinical parameters that can predict the presence and severity of obstructive sleep apnea. SUBJECTS AND METHODS: Adult patients with habitual snoring completed comprehensive polysomnography and anthropometric measurements, including sex, age, body mass index (BMI), neck circumference, tonsil size grading, modified Mallampati score, and nasofibroscopy-assisted Muller's maneuver (NMM). Spearman's correlation coefficient was used to screen the significant variables. Stepwise multiple linear regression analysis was then conducted to identify the independent variables. receiver operating characteristic (ROC) curve analysis was used to quantify the predictability of the formed oropharyngeal obstruction scoring system. RESULTS: A total of 163 adults (127 men) were enrolled in the study. Tonsil size grading, modified Mallampati score, and NMM grading maneuver were predictive of  OSA and incorporated into a scoring system. This score ranged between 3 and 12, and threshold values of ≥ 8 and ≥ 9 seemed to be appropriate to identify patients at an increased risk of at least mild (AHI ≥ 5/h; AUROC = 0.935, 95%CI = 0.900-0.970, P < 0.001) and severe OSA (AHI ≥ 30/h; AUROC = 0.939, 95%CI = 0.899-0.969, P < 0.001), respectively. CONCLUSION: This study established an evaluation score for assessing the degree of oropharhygeal obstruction. The findings of the study suggest that the score may help identify patients at risk of oropharyngeal-related OSA who should have a full sleep evaluation.


Assuntos
Polissonografia , Apneia Obstrutiva do Sono , Humanos , Masculino , Feminino , Apneia Obstrutiva do Sono/diagnóstico , Adulto , Pessoa de Meia-Idade , Orofaringe/fisiopatologia , Obstrução das Vias Respiratórias/diagnóstico , Índice de Gravidade de Doença , Ronco/diagnóstico , Reprodutibilidade dos Testes
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