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1.
PLoS Comput Biol ; 19(6): e1011193, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37384793

RESUMO

Gestational Diabetes Mellitus (GDM), a serious complication during pregnancy which is defined by abnormal glucose regulation, is commonly treated by diabetic diet and lifestyle changes. While recent findings place the microbiome as a natural mediator between diet interventions and diverse disease states, its role in GDM is still unknown. Here, based on observation data from healthy pregnant control group and GDM patients, we developed a new network approach using patterns of co-abundance of microorganism to construct microbial networks that represent human-specific information about gut microbiota in different groups. By calculating network similarity in different groups, we analyze the gut microbiome from 27 GDM subjects collected before and after two weeks of diet therapy compared with 30 control subjects to identify the health condition of microbial community balance in GDM subjects. Although the microbial communities remain similar after the diet phase, we find that the structure of their inter-species co-abundance network is significantly altered, which is reflected in that the ecological balance of GDM patients was not "healthier" after the diet intervention. In addition, we devised a method for individualized network analysis of the microbiome, thereby a pattern is found that GDM individuals whose microbial networks are with large deviations from the GDM group are usually accompanied by their abnormal glucose regulation. This approach may help the development of individualized diagnosis strategies and microbiome-based therapies in the future.


Assuntos
Diabetes Gestacional , Microbioma Gastrointestinal , Microbiota , Gravidez , Feminino , Humanos , Microbioma Gastrointestinal/fisiologia , Dieta , Glucose
2.
Int Endod J ; 56(5): 608-621, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36648366

RESUMO

INTRODUCTION: Microbial function changes may be responsible for dental pulp transformation from normal to diseased. However, studies on the prediction and verification of the function of the microbial community in the deep dentine and pulp of caries-induced pulpitis are lacking. METHODS: This study included 171 cases of deep dentinal caries divided into normal pulp (NP), reversible pulpitis (RP), and irreversible pulpitis (IRP). In Experiment I, the microbial community composition was identified in 111 samples using 16S ribosomal DNA. Function prediction was performed through phylogenetic investigation of communities by Phylogenetic Investigation of Communities by Reconstruction of Unobserved States prediction and qPCR. In Experiment II, different microbiome functions were confirmed in 60 samples using liquid chromatography-tandem mass spectrometry. RESULTS: In Experiment I, microbial abundance significantly differed in the IRP group compared to the other two groups. The RP and NP groups had the same microbiome composition, but the predicted functional difference between the RP and NP groups pertained to membrane transport (p < .010). The predicted functional difference between the IRP and NP groups pertained to amino-acid, co-factor, and vitamin metabolism (p < .010). In Experiment II, Kyoto Encyclopedia of Genes and Genomes functional annotation revealed that the differential metabolites between the RP and NP groups did not participate in membrane transport; however, the differential metabolites between the IRP and NP groups participated in amino-acid metabolism. CONCLUSIONS: The near-pulp microbiome in RP and NP with deep dentinal caries had the same differential function. However, amino acid metabolism in near the pulp microbial community differed between IRP and NP with deep dentinal caries.


Assuntos
Cárie Dentária , Microbiota , Pulpite , Humanos , Suscetibilidade à Cárie Dentária , Filogenia , Polpa Dentária
3.
Eur Arch Otorhinolaryngol ; 280(2): 681-688, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35870003

RESUMO

PURPOSE: We aimed to clarify the clinical features of delayed-onset swelling around cochlear implants (CI), and to present our experience on how to avoid and address this problem. METHODS: We performed a retrospective review of all CI cases at our institution between June 2001 and June 2020. Information on postoperative complications of swelling in the receiver area > 3 months after implantation were analyzed, and clinical data sheets were drawn. RESULTS: Twenty-six of 1425 patients (1.82%) with an age at implantation ranging from 1 to 9 years experienced delayed-onset swelling around the implant. Swelling episodes occurred as early as 4 months, and as late as 178 months after implantation (median, 79.7 months). The predisposing factor in 12 cases was unclear, 7 cases were caused by trauma at the implantation site, 5 cases were without predisposing factors, and 2 cases were related to infection. We found the frequency of delayed-onset swelling after cochlear implantation with different incision was statistically insignificant (P = 0.423). Nineteen patients (73.1%) were cured after one treatment, and five patients (19.2%) relapsed. Follow-up examinations at least 18 months after surgery revealed that all patients experienced a complete recovery. CONCLUSIONS: Delayed-onset swelling at the receiver site is a long term but not exactly uncommon complication after cochlear surgery and long-term follow-up is eagerly required. It can recur more than once, causing more complex treatment strategies in clinical practice. Conservative treatment first recommended, while needle aspiration should initially be considered in recurrent cases also when the effusion swelling is > 3 ml.


Assuntos
Implante Coclear , Implantes Cocleares , Humanos , Lactente , Pré-Escolar , Criança , Implante Coclear/efeitos adversos , Implantes Cocleares/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos , Cóclea
4.
Lifetime Data Anal ; 29(1): 234-252, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36593432

RESUMO

Quantile residual lifetime (QRL) is of significant interest in many clinical studies as an easily interpretable quantity compared to other summary measures of survival distributions. In cancer or other chronic diseases, treatments are often compared based on the distributions or quantiles of the residual lifetime. Thus a common problem of interest is to test the equality of the QRL between two populations. In this paper, we propose two classes of tests to compare two QRLs; one class is based on the difference between two estimated QRLs, and the other is based on the estimating function of the QRL, where the estimated QRL from one sample is plugged into the QRL-estimating-function of the other sample. We outline the asymptotic properties of these test statistics. Simulation studies demonstrate that the proposed tests produced Type I errors closer to the nominal level and are superior to some existing tests based on both Type I error and power. Our proposed test statistics are also computationally less intensive and more straightforward compared to tests based on the confidence intervals. We applied the proposed methods to a randomized multicenter phase III trial for breast cancer patients.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Análise de Sobrevida , Simulação por Computador
5.
Carcinogenesis ; 43(3): 264-276, 2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-34718437

RESUMO

ATP-dependent chromatin remodeling complexes regulate chromatin structure and play important roles in gene expression, differentiation, development and cancer progression. Dysregulation in the subunits of the complexes often has been found in different cancers, but how they influence cancer initiation and progression is not fully understood. Here, we show that Chromatin Accessibility Complex Subunit 1 (CHRAC1), the accessory subunit of chromatin remodeling complex, is highly expressed in lung cancer tissues, which correlates with poor prognosis in lung cancer patients. CHRAC1 overexpression promotes lung cancer cell proliferation and migration in vitro and tumor growth in genetically engineered KrasG12D.LSL lung adenocarcinoma mouse model. Consistent with this, CHRAC1 silencing inhibits cell proliferation and migration in lung cancer cells and suppresses tumor growth in xenograft mouse model. Further, CHRAC1 binds to the transcription coactivator Yes-associated protein (YAP), enhances the transcription of downstream target oncogenes in Hippo pathway and thus promotes the tumor growth. Together, our study defines a critical role of CHRAC1 in promoting YAP transcriptional activity and lung cancer tumorigenesis, which makes it a potential target for lung cancer.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/genética , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Cromatina , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Nucleoproteínas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Biol Cell ; 113(1): 14-27, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32942336

RESUMO

BACKGROUND INFORMATION: Diabetes-induced testicular dysfunction is characterised by abnormal apoptosis of spermatogenic cells, but the underlying mechanism is poorly understood. This study aimed to investigate the roles of clusterin (CLU) in testicular damage associated with diabetes pathogenesis, as well as the molecular mechanism. A rat diabetes model was established using streptozocin, and the mouse spermatogenic cell line GC-1 spg was treated with high glucose as a cellular model. CLU was overexpressed in GC-1 spg cells, followed by detection of serum testosterone, cell proliferation, cell apoptosis and autophagy. RESULTS: CLU expression was significantly reduced and LC3 expression was elevated in testis tissues in the rat diabetes model and high glucose-treated GC-1 spg cells. High glucose led to suppressed viability, enhanced apoptosis, reduced Bcl-2 expression, elevated Bax expression and cleavage of Caspase-3/-9 in GC-1 spg cells, and these effects were abrogated by CLU overexpression. Additionally, CLU overexpression repressed LC3 and Beclin-1 expression, reduced the LC3II/LC3I ratio and promoted p62 expression in GC-1 spg cells in the presence of high glucose, and these effects were all mitigated by rapamycin treatment. Inhibition of PI3K/AKT/mTOR signalling with LY294002 activated autophagy in CLU-overexpressing GC-1 spg cells under high glucose conditions. CLU overexpression repressed autophagy and alleviated testicular damage in diabetic rats, which was also abrogated by LY294002 treatment. CONCLUSIONS: CLU expression is suppressed during diabetes-induced testicular damage, whereas CLU overexpression alleviates diabetes-induced testicular damage by activating PI3K/AKT/mTOR signalling to inhibit autophagy and further repress spermatogenic cell apoptosis.


Assuntos
Clusterina/fisiologia , Diabetes Mellitus Experimental/patologia , Testículo , Animais , Apoptose , Linhagem Celular , Proliferação de Células , Masculino , Camundongos , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Testículo/metabolismo , Testículo/patologia
7.
BMC Pregnancy Childbirth ; 22(1): 533, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778690

RESUMO

BACKGROUND: Pregnancy induces cognitive reorganization which can lead to mental disorders. The aim of this study is to determine differences in cognitive scores, short-chain fatty acids (SCFAs) and related metabolites between pregnant and non-pregnant participants. METHODS: This cross-sectional study included 67 full-term pregnant women and 31 non-pregnant women. We compared scores of mental state and cognitive assessment tests, as well as serum concentrations of SCFAs, hormones, inflammatory factors, and neurotransmitters between these groups. RESULTS: Scores for information processing speed, immediate visual memory, motor response speed and accuracy, execution ability and verbal use ability in the pregnant group were lower than those in the non-pregnant group (p < 0.05 for all tests). Total serum SCFAs in the pregnant group were significantly lower than those in the non-pregnant group (P = 0.031). Among them, acetate and propionate were significantly decreased (P = 0.013 and 0.037, respectively) whereas butyrate was significantly increased (P = 0.035). Serum peptide YY, glucagon-like peptide-1, γ-aminobutyric acid, and dopamine showed no differences between the two groups. However, cortisol, adrenocorticotropic hormone, and acetylcholine were significantly increased in the pregnant group as compared with the non-pregnant group (P = 0.039, 0.016, and 0.012, respectively). Tumor necrosis factor-α was increased and interleukin-10 significantly decreased in the pregnant group (P = 0.045 and 0.019, respectively). CONCLUSION: According to our study findings, cognitive reorganization in the third trimester of pregnancy showed that both the passive storage capacity of working memory and the executive function of online information processing were decreased to varying degrees. At the same time, the changes in total SCFAs, the proportions of SCFAs and related metabolites were also detected. These changes in the internal environment may be increasing the risk of perinatal mental illness.


Assuntos
Cognição , Ácidos Graxos Voláteis , Estudos Transversais , Ácidos Graxos Voláteis/metabolismo , Feminino , Humanos , Gravidez , Terceiro Trimestre da Gravidez
8.
Entropy (Basel) ; 24(8)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-36010737

RESUMO

The Belief Propagation (BP) algorithm has the advantages of high-speed decoding and low latency. To improve the block error rate (BLER) performance of the BP-based algorithm, the BP flipping algorithm was proposed. However, the BP flipping algorithm attempts numerous useless flippings for improving the BLER performance. To reduce the number of decoding attempts needed without any loss of BLER performance, in this paper a metric is presented to evaluate the likelihood that the bits would correct the BP flipping decoding. Based on this, a BP-Step-Flipping (BPSF) algorithm is proposed which only traces the unreliable bits in the flip set (FS) to flip and skips over the reliable ones. In addition, a threshold ß is applied when the magnitude of the log-likelihood ratio (LLR) is small, and an enhanced BPSF (EBPSF) algorithm is presented to lower the BLER. With the same FS, the proposed algorithm can reduce the average number of iterations efficiently. Numerical results show the average number of iterations for EBPSF-1 decreases by 77.5% when N = 256, compared with the BP bit-flip-1 (BPF-1) algorithm at Eb/N0 = 1.5 dB.

9.
Appl Opt ; 60(23): 6878-6887, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34613169

RESUMO

Effective information mining of fiber-optic distributed acoustic sensors (DAS) is so important that it attracts more and more public attention, and various manual and deep feature extraction methods have been developed. However, either way it has limits; for example, the manual features contain insufficient information, and the deep features could be unreliable because of the overfitting problem. Thus, in this paper, to avoid the disadvantages of each and make full use of the effective information carried by DAS signals, an intelligent target recognition method by utilizing both manual and deep features is proposed. The manual features are first extracted in the time domain, frequency domain, semantic domain, and from dynamic models, which are fused with the deep features extracted by a four-layer 1D convolutional neural network (CNN) through feature engineering. The features are ranked and then selected by a combined weighting method of analysis of variance and maximum information coefficient. Then finally, an optimal classifier is selected by comparing support vector machine, extreme gradient boost, random forest, and native Bayesian. In the test with real field data, four types of features, which include the manual features, the CNN features, and the combined features without and with selection, are compared with these different classifiers. As a result, it shows the combined features without selection can improve the identification ability of DAS compared with the recognition with only manual or deep features. The combined features with selection can further improve the computation efficiency and save up to 90% of time with a performance degradation of less than 1%.

10.
BMC Musculoskelet Disord ; 22(1): 836, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34587928

RESUMO

BACKGROUND: Many solutions have been proposed in treating of forearm supination. Comparing with other supination function reconstructions, pronator teres rerouting is believed to be less effective due to its insufficient supination strength. The aim of this study is to introduce a modified procedure, and compare its result with two previous approaches. PATIENTS AND METHODS: From 2015 to 2020, 11 patients have restored forearm supination by rerouting of the pronator teres weave sutured with allogeneic tendons. The average follow-up period was 17.5 months (12 to 24). The range of active supination at the final follow-up was recorded. RESULTS: Almost all patients acquired good supination range. The average active post-operative supination was 72.7° (60° to 80°) at the final follow-up. No complication was observed. All patients retained full range of pronation. CONCLUSIONS: This study provides a modified supination function reconstruction with simple operating, fine results, low risks, and no affecting of pronation function. The use of allogeneic tendon makes up for the muscles with insufficient length, making it valuable to reconsider those rebuilding operations that were once considered unpromising by many.


Assuntos
Antebraço , Transplante de Células-Tronco Hematopoéticas , Humanos , Supinação , Transferência Tendinosa , Tendões/cirurgia
11.
BMC Oral Health ; 21(1): 339, 2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34246278

RESUMO

BACKGROUND: According to the diagnosis criteria of the American Association of Endodontists (AAE), sensitive responses to cold and/or heat tests of suspected teeth compared with those of control teeth can be used for the diagnosis of pulpitis, but the role of electric pulp test (EPT) is not mentioned. It is believed that EPT has some limitations in determining the vitality of the pulp. The aim of this study was to explore the association between the difference in EPT values and the differential diagnoses of reversible pulpitis (RP) and symptomatic irreversible pulpitis (SIRP) caused by dental caries. METHODS: A total of 203 cases with pulpitis caused by dental caries were included. A diagnosis of pulpitis was made on the basis of the diagnostic criteria of AAE. Patient demographic and clinical examination data were collected. The EPT values of the suspected teeth and control teeth were measured, and the differences between them were calculated. The correlation between the difference in the EPT values and diagnosis of pulpitis was analyzed using univariate and multivariate logistic regression. RESULTS: In the 203 cases (78 males and 125 females; 115 cases of RP, 88 cases of SIRP; 9 anterior teeth, 59 premolars, and 135 molars), the mean patient age was 34.04 ± 13.02 (standard deviation) years. The unadjusted (crude) model, model 1 (adjusted for age), model 2 (adjusted for age and sex), and model 3 (adjusted for age, sex, and tooth type) were established for the statistical analyses. In model 3 [odds ratio (OR) = 1.025; 95% confidence interval (CI) 1.002-1.050; P = 0.035], the difference in EPT values between RP and SIRP was statistically significant. However, the areas under the curve of predictive probability of the crude model, model 1, model 2, and model 3 were 0.565, 0.570, 0.585, and 0.617, respectively, showing that the model accuracy was low. The P-value for the trend in differences between the EPT values as a categorical variable showed that the differences in the EPT values, comparing RP and SIRP, were not statistically significant. CONCLUSIONS: Based on the present data, the difference in EPT values was not sufficient to differentiate RP from SIRP.


Assuntos
Cárie Dentária , Pulpite , Adulto , Cárie Dentária/diagnóstico , Polpa Dentária , Teste da Polpa Dentária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dente Molar , Pulpite/diagnóstico , Adulto Jovem
12.
Anal Biochem ; 597: 113673, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32142761

RESUMO

Schaftoside is a flavone-C-glycoside isolated from Herba Desmodii Styracifolii with valuable anti-kidney stones efficacies. In this study, a six-step strategy was first developed to detect and identify the metabolites in plasma, urine, bile, feces and rat intestinal bacteria samples of healthy and model rats administrated with schaftoside using ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS). The number and the relative peak area of metabolites in healthy rats and model rats were compared, and it was noticed that metabolites in bio-samples of healthy and model rats both had obvious differences. A total of 28 metabolites of schaftoside in healthy rats and 30 metabolites in model rats were initially indentified. The relative peak area of the parent drug and every metabolite in model rat plasma samples were larger than those in healthy rat plasma. Those metabolites with high blood concentrations might be beneficial for the treatment of calcium oxalate stones in the kidney. The results are valuable and important for understanding the metabolic process of schaftoside in clinical application, and especially the metabolism study in calcium oxalate kidney stone model rats could provide a beneficial reference for the further search of effective substances associated with the treatment of kidney stones.


Assuntos
Oxalato de Cálcio/metabolismo , Glicosídeos/metabolismo , Cálculos Renais/química , Animais , Oxalato de Cálcio/sangue , Oxalato de Cálcio/urina , Modelos Animais de Doenças , Glicosídeos/sangue , Glicosídeos/urina , Cálculos Renais/sangue , Cálculos Renais/urina , Masculino , Ratos , Ratos Sprague-Dawley
13.
BMC Infect Dis ; 20(1): 537, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703176

RESUMO

BACKGROUND: Twelve students experienced symptoms of acute respiratory infection (ARI) at a training base in Beijing from August 26 to August 30, 2015. We investigated the cause of this ARI outbreak. METHODS: In partnership with the local center for disease control, we collected a total of twelve pharyngeal swab specimens as well as demographic information for the affected patients. We used multiplex real-time PCR to screen for sixteen common respiratory viruses in these samples. To isolate HAdV, we inoculated Hep-2 cells with the human adenovirus (HAdV)-positive samples and then carried out sequencing and phylogenetic analysis of the hexon, fiber, and penton genes of the isolated adenoviruses. In addition, we analyzed the entire genome of one strain isolated from the index case to identify single-nucleotide substitutions. RESULTS: We identified ten HAdV-positive students using multiplex real-time PCR. None of the students were co-infected with other viruses. We successfully isolated seven HAdV strains from the pharyngeal swab specimens. The coding sequences of the hexon, fiber, and penton genes of these seven HAdV strains were identical, suggesting that they represented seven strains from a single virus clone. One HAdV isolate obtained from the index case, BJDX-01-2015, was selected for whole genome analysis. From this isolate, we obtained a 34,774-nucleotide sequence. The genome of BJDX-01-2015 clustered with HAdV-B55 in phylogenetic analyses and had 99.97% identity with human adenovirus 55 isolate HAdV-B/CHN/BJ01/2011/55 (GenBank accession no. JX491639). CONCLUSIONS: We identified HAdV-B55 as the strain associated with the August 2015 ARI outbreak at a training base in Beijing. This was the first reported outbreak in Beijing due to HAdV-B55. Continuous surveillance of respiratory adenoviruses is urgently needed to understand the epidemiological and evolutionary features of HAdV-B55, and an epidemiological modeling approach may provide further insights into this emerging public health threat. Furthermore, the clinical laboratory data from this outbreak provides important reference for the clinical diagnosis and may ultimately aid in informing the development of strategies to control and prevent respiratory tract infections caused by HAdV-B55.


Assuntos
Infecções por Adenovirus Humanos/epidemiologia , Adenovírus Humanos/genética , Surtos de Doenças , Infecções Respiratórias/epidemiologia , Infecções por Adenovirus Humanos/virologia , Adolescente , Pequim/epidemiologia , Humanos , Incidência , Masculino , Reação em Cadeia da Polimerase Multiplex , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Infecções Respiratórias/virologia , Estudantes , Sequenciamento Completo do Genoma
14.
J Sep Sci ; 43(12): 2363-2379, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32227654

RESUMO

Isovitexin, a bioactive flavonoid constituent isolated from Desmodii Styracifolii, is considered an adjuvant for antiurolithiasis diseases. In this study, an ultra-high-performance liquid chromatography coupled with hybrid triple quadruple time-of-flight mass spectrometry method was developed to characterize and compare the metabolic profiling of isovitexin experimented on normal and kidney stone model rats. The comparative research indicated that 28 metabolites (18 phase I and 10 phase II) in normal rats and 33 metabolites (20 phase I and 13 phase II) in kidney stone model rats were initially identified. The results of relative quantitative determination reflected that the contents of metabolites produced by deglycosylation, reduction, and isomerization in kidney stone model rats were greater than those in healthy rats. Instead, the levels of oxidative and dehydrogenated metabolites in normal groups were higher than those in kidney stone model groups. The results of this study are valuable and important for understanding the metabolic process of isovitexin in clinical application, and especially the metabolism study in kidney stone model rats could provide a beneficial reference for the further search of effective substances associated with the treatment of kidney stones.


Assuntos
Apigenina/metabolismo , Modelos Animais de Doenças , Cálculos Renais/química , Animais , Apigenina/análise , Cromatografia Líquida de Alta Pressão , Cálculos Renais/metabolismo , Masculino , Espectrometria de Massas , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
15.
Neural Plast ; 2020: 4576729, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32774355

RESUMO

Music perception in cochlear implant (CI) users is far from satisfactory, not only because of the technological limitations of current CI devices but also due to the neurophysiological alterations that generally accompany deafness. Early behavioral studies revealed that similar mechanisms underlie musical and lexical pitch perception in CI-based electric hearing. Although neurophysiological studies of the musical pitch perception of English-speaking CI users are actively ongoing, little such research has been conducted with Mandarin-speaking CI users; as Mandarin is a tonal language, these individuals require pitch information to understand speech. The aim of this work was to study the neurophysiological mechanisms accounting for the musical pitch identification abilities of Mandarin-speaking CI users and normal-hearing (NH) listeners. Behavioral and mismatch negativity (MMN) data were analyzed to examine musical pitch processing performance. Moreover, neurophysiological results from CI users with good and bad pitch discrimination performance (according to the just-noticeable differences (JND) and pitch-direction discrimination (PDD) tasks) were compared to identify cortical responses associated with musical pitch perception differences. The MMN experiment was conducted using a passive oddball paradigm, with musical tone C4 (262 Hz) presented as the standard and tones D4 (294 Hz), E4 (330 Hz), G#4 (415 Hz), and C5 (523 Hz) presented as deviants. CI users demonstrated worse musical pitch discrimination ability than did NH listeners, as reflected by larger JND and PDD thresholds for pitch identification, and significantly increased latencies and reduced amplitudes in MMN responses. Good CI performers had better MMN results than did bad performers. Consistent with findings for English-speaking CI users, the results of this work suggest that MMN is a viable marker of cortical pitch perception in Mandarin-speaking CI users.


Assuntos
Encéfalo/fisiologia , Encéfalo/fisiopatologia , Implantes Cocleares , Surdez/fisiopatologia , Surdez/psicologia , Música , Discriminação da Altura Tonal/fisiologia , Estimulação Acústica , Adolescente , Adulto , Criança , Eletroencefalografia , Feminino , Humanos , Masculino , Psicoacústica , Adulto Jovem
16.
Fish Physiol Biochem ; 46(6): 1981-1990, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32676986

RESUMO

Naked carp (Gymnocypris przewalskii), endemic to the saline-alkaline Lake Qinghai, have the capacity to tolerate combined hypoxia and high alkalinity. This study evaluated the effect of the interaction between carbonate alkalinity and hypoxia on ammonia excretion and blood gas variation in naked carp. Naked carp were subjected to normoxic, hypoxic and reoxygenation phases at two different carbonate alkalinity levels (CA0 = 0 mmol/L; CA32 = 32 mmol/L) for 4 days. The ammonia excretion rate (JAmm) of the CA0 group rapidly decreased under hypoxia and recovered under normoxia for four consecutive days. The JAmm under CA32 also decreased under hypoxia and recovered to its previous level in the first 2 days. However, the JAmm under CA32 was lower than that under CA0. The blood pO2, sO2 of CA0 and CA32 group was significantly reduced under hypoxia, after which both groups recovered. Blood pCO2 of the CA32 group was lower than CA0 throughout the experiment. There were no changes in haematocrit of the naked carp exposed to carbonate alkalinity and hypoxia. The alkaline water increased the pH of the blood and contributed to increased haemoglobin O2 affinity. Overall, the present findings reveal that naked carp is a tolerant species that can maintain main ionic homeostasis under severe alkalinity and hypoxia. The high alkaline water is beneficial for naked carp to adapt to hypoxic environment.


Assuntos
Amônia/metabolismo , Carpas/metabolismo , Anaerobiose , Animais , Gasometria , Dióxido de Carbono/sangue , Carbonatos , Carpas/sangue , Concentração de Íons de Hidrogênio , Oxigênio/sangue
17.
Am J Ind Med ; 62(3): 192-204, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30676651

RESUMO

OBJECTIVES: To evaluate long-term mortality rates among aerospace material manufacturing workers as follow-up to an earlier observed excess of nephritis/nephrosis. METHODS: Subjects were 2020 workers ever employed in the facility during 1963-2014. Vital status through 2014 was determined for all subjects and cause of death for 99.2% of 492 deaths. We computed standard mortality ratios (SMR) and internal relative risks. RESULTS: SMRs for nephritis/nephrosis were unremarkable. We observed statistically significant elevated SMRs for kidney cancer among all workers and for the category "other lymphatic hematopoietic tissue cancer" (4/5 deaths from multiple myeloma) among long-term workers with potential plant exposure. CONCLUSIONS: We found no evidence of elevated mortality rates for nephritis/nephrosis. Study limitations precluded robust evaluation of whether the elevated rates for kidney cancer and other lymphatic hematopoietic tissue cancer were related to occupational factors at the study site. Our findings for these two cancers warrant continued mortality follow-up.


Assuntos
Causas de Morte , Neoplasias Renais/mortalidade , Indústria Manufatureira/estatística & dados numéricos , Mieloma Múltiplo/mortalidade , Doenças Profissionais/mortalidade , Adesivos , Adulto , Idoso , Idoso de 80 Anos ou mais , Aviação , Estudos de Coortes , Feminino , Humanos , Masculino , Maryland/epidemiologia , Pessoa de Meia-Idade , Nefrite/mortalidade , Nefrose/mortalidade , Estados Unidos/epidemiologia
18.
Stat Med ; 37(6): 983-995, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29235127

RESUMO

Adherence to medication is critical in achieving effectiveness of many treatments. Factors that influence adherence behavior have been the subject of many clinical studies. Analyzing adherence is complicated because it is often measured on multiple drugs over a period, resulting in a multivariate longitudinal outcome. This paper is motivated by the Viral Resistance to Antiviral Therapy of Chronic Hepatitis C study, where adherence is measured on two drugs as a bivariate ordinal longitudinal outcome. To analyze such outcome, we propose a joint model assuming the multivariate ordinal outcome arose from a partitioned latent multivariate normal process. We also provide a flexible multilevel association structure covering both between and within outcome correlation. In simulation studies, we show that the joint model provides unbiased estimators for regression parameters, which are more efficient than those obtained through fitting separate model for each outcome. The joint method also yields unbiased estimators for the correlation parameters when the correlation structure is correctly specified. Finally, we analyze the Viral Resistance to Antiviral Therapy of Chronic Hepatitis C adherence data and discuss the findings.


Assuntos
Estudos Longitudinais , Adesão à Medicação , Análise de Regressão , Simulação por Computador , Farmacorresistência Viral Múltipla , Hepatite C/tratamento farmacológico , Humanos , Análise Multivariada
19.
Phys Chem Chem Phys ; 20(25): 17497-17503, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29911701

RESUMO

A recent discovery of anionic redox activity in Li-rich layered compounds opens a new direction for the design of high-capacity cathode materials for lithium-ion batteries. Here using extensive ab initio calculations, the thermodynamic existence of the Li-rich phase in LiFePO4 to form Li1+xFe1-xPO4 with x not exceeding 12.5% has been proved. Anionic redox activity and structural stability during delithiation are further investigated. Interestingly, it is found that Li1+xFe1-xPO4 cannot be delithiated completely and thus cannot achieve extra capacity by anionic redox activity, because the local oxygen-ion redox will cause the fracture of the rigid framework formed by phosphate tetrahedral polyanions. Although an extra capacity cannot be realized, the excess Li-ions at Fe sites can enhance the Li-ion diffusivity along the adjacent [010] channel and contribute to the shift from 1D to 2D/3D diffusion. This study provides a fresh perspective on olivine-type LiFePO4 and offers some important clues on designing Li-rich cathode materials with high energy density.

20.
Aging Clin Exp Res ; 30(4): 395-405, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28702899

RESUMO

INTRODUCTION: Oxidative injury to the brain and aging are theoretical co-causes of Alzheimer's Disease (AD). Amyloid plaques and tangles are then secondary phenomenon. The preclinical state would then be 'normal' elderly. METHODS: A potent complex antioxidant (antiOx) was tested against a popular one-a-day multivitamin (mV) in a randomized single blind design in 'normal' senior subjects over 6 months. Memory testing was done at baseline, 1, 3, and 6 months. The generalized estimating equation (GEE) approach was used to compare the change score of NLT100 and 20WR between two groups over time. RESULTS: Analysis of the antiOx group (30 subjects) demonstrated significant improvement in declarative memory (change score for NLT100 at month 6 = 6.36 p < 0.0001) and working memory (change score for 20WR at month 6 = 3.23, p < 0.0001). A change-score analysis over 6 months suggests possible neurogenesis in the antiOx group. The mV group (33 subjects) had a change score of the NLT100 and 20WR on the sixth month of 2.20 and 0.32 (p = 0.07, 0.35). CONCLUSIONS: A complex antioxidant blend, sold as an over-the-counter (OTC) supplement, can improve memory in elder subjects. Antioxidants may be beneficial in AD and other neurodegerative diseases.


Assuntos
Antioxidantes/administração & dosagem , Memória/efeitos dos fármacos , Idoso , Doença de Alzheimer/tratamento farmacológico , Suplementos Nutricionais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego
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