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1.
Polymers (Basel) ; 16(9)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38732739

RESUMO

Developing high-performance and low-cost protein purification materials is of great importance to meet the demands for highly purified proteins in biotechnological industries. Herein, a facile strategy was developed to design and construct high-efficiency protein absorption and separation media by combining aerogels' molding techniques and impregnation processes. Poly (ethylene-co-vinyl alcohol) (EVOH) nanofibrous aerogels (NFAs) were modified by grafting butane tetracarboxylic acid (BTCA) over them in situ. This modification was carried out using polyphosphoric acid as a catalyst. The resulting EVOH/BTCA NFAs exhibited favorable comprehensive properties. Benefiting from the highly interconnected porous structure, good underwater compressive properties, and abundant absorption ligands, the obtained EVOH/BTCA NFAs possessed a high static absorption capacity of 1082.13 mg/g to lysozyme and a short absorption equilibrium time of about 6 h. A high saturated dynamic absorption capacity for lysozyme (716.85 mg/g) was also realized solely by gravity. Furthermore, EVOH/BTCA NFAs displayed excellent reusability, good acid and alkaline resistance, and unique absorption selectivity performance. The successful synthesis of such aerogels can provide a potential candidate for next-generation protein absorbents for bio-separation and purification engineering.

2.
Front Neurosci ; 16: 935834, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090279

RESUMO

Single-sided deafness (SSD) is an extreme case of partial hearing deprivation and results in a significant decline in higher-order hearing abilities, including sound localization and speech-in-noise recognition. Clinical studies have reported that patients with SSD recover from these higher-order hearing abilities to some extent over time. Neuroimaging studies have observed extensive brain functional plasticity in patients with SSD. However, studies investigating the role of plasticity in functional compensation, particularly those investigating the relationship between intrinsic brain activity alterations and higher-order hearing abilities, are still limited. In this study, we used resting-state functional MRI to investigate intrinsic brain activity, measured by the amplitude of low-frequency fluctuation (ALFF), in 19 patients with left SSD, 17 patients with right SSD, and 21 normal hearing controls (NHs). All patients with SSD had durations of deafness longer than 2 years. Decreased ALFF values in the bilateral precuneus (PCUN), lingual gyrus, and left middle frontal gyrus were observed in patients with SSD compared with the values of NHs. Longer durations of deafness were correlated with better hearing abilities, as well as higher ALFF values in the left inferior parietal lobule, the angular gyrus, the middle occipital gyrus, the bilateral PCUN, and the posterior cingulate gyrus. Moreover, we observed a generally consistent trend of correlation between ALFF values and higher-order hearing abilities in specific brain areas in patients with SSD. That is, better abilities were correlated with lower ALFF values in the frontal regions and higher ALFF values in the PCUN and surrounding parietal-occipital areas. Furthermore, mediation analysis revealed that the ALFF values in the PCUN were a significant mediator of the relationship between the duration of deafness and higher-order hearing abilities. Our study reveals significant plasticity of intrinsic brain activity in patients with SSD and suggests that reorganization of intrinsic brain activity may be one of the compensatory mechanisms that facilitate improvement in higher-order hearing abilities in these patients over time.

3.
Med Image Anal ; 73: 102163, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34303170

RESUMO

As an extreme type of partial auditory deprivation, single-sided deafness (SSD) has been demonstrated to lead to extensive neural plasticity according to multimodal neuroimaging studies. Among them, resting-state functional magnetic resonance imaging (rs-fMRI) offers valuable information on functional connectivities (FCs). However, most previous SSD rs-fMRI studies assumed that the extracted FC remains stationary during the entire fMRI scan and neglected dynamic functional activities. Existing fixed window-based dynamic FC analysis also ignores dynamic functional activities under different temporal terms. Additionally, due to the cost constraints of using MRI machines, using data-driven methods for unbiased hypothesis investigations may require more effective sample data augmentation techniques. To tackle these challenges and problems together, in this study, we proposed a dynamic window with a random length and position to extract participants' dynamic characteristics under different temporal terms and to extract more information from the dataset. Then, we proposed a nodal efficiency-based correlation matrix to describe the relationships of synergism between regions as features and applied a linear support vector machine (SVM) model to learn the importance of the features, which helped to identify SSD patients and healthy controls. A total of 68 participants (including 23 with left SSD, 20 with right SSD and 25 healthy controls) were enrolled. Our proposed approach with a random window showed clear improvement compared with traditional static and fixed window-based dynamic FC by using the linear SVM model. FCs related to the frontoparietal, somatomotor, dorsal attention, limbic and default mode networks played significant roles in differentiating SSD patients from healthy controls. Additionally, FCs between the somatomotor and frontoparietal networks made the greatest contribution to the classification model. Regarding brain regions, FCs related to the superior frontal gyrus, superior parietal lobule, superior temporal gyrus, amygdala, and orbital gyrus played significant roles. These findings suggest that networks and regions related to higher-order cognitive functions showed the most significant FC alterations in SSD, which may represent a compensatory collaboration of cognitive resources in SSD.


Assuntos
Encéfalo , Surdez , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Cognição , Humanos , Imageamento por Ressonância Magnética , Vias Neurais
4.
Ear Nose Throat J ; 100(3_suppl): 333S-336S, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32791904

RESUMO

We report a 6-year-old girl with progressive bilateral conductive hearing loss for 2 years. She passed the newborn hearing screening conducted with otoacoustic emissions testing and had a normal development of speech and language, which indicated that her deafness was delayed-onset. She also had congenital proximal interphalangeal joints. Proximal symphalangism was confirmed by genetic testing (NOG gene: c.406C > T, p.R136C). Bilateral stapes ankyloses were proved by surgery and her hearing was improved after stapedotomy by over 30 dB. Besides, this case should remind clinicians to carefully distinguish NOG gene-related deafness from congenital ossicular malformation and pediatric otosclerosis.


Assuntos
Proteínas de Transporte/genética , Articulações dos Dedos/anormalidades , Perda Auditiva Bilateral/diagnóstico , Perda Auditiva Condutiva/diagnóstico , Artropatias/congênito , Estribo/anormalidades , Audiometria de Tons Puros , Criança , Diagnóstico Diferencial , Feminino , Perda Auditiva Bilateral/genética , Perda Auditiva Condutiva/genética , Humanos , Artropatias/diagnóstico , Artropatias/genética , Ilustração Médica , Cirurgia do Estribo
5.
Hear Res ; 380: 75-83, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31200333

RESUMO

Growing evidence shows that partial auditory deprivation leads to extensive neural functional plasticity, which occurs not only in the auditory cortex but also in other sensory regions and cognitive areas. However, studies in structural topological properties are still limited, especially those investigating the relationship between structural connectome alterations and auditory abilities. To clarify this, we investigated white matter structural connectivity changes and the relationship between connection strength and hearing abilities in individuals with long-term single-sided deafness (SSD), a common form of partial hearing deprivation, using diffusion tensor imaging and network-based analysis. The results showed globally improved connection efficiency, locally weakened visual networks, and strengthened fronto-parietal sub-networks in SSD compared to normal hearing controls. Furthermore, a strong positive correlation between hearing abilities (including speech recognition in noise and sound localization) and connection strength, mainly in the fronto-parietal areas, was found in SSD. Our study reveals alteration of the structural network connections in SSD, especially in cognitive related networks, which showed close correlation with hearing abilities. Our findings provide new insights into topological white matter reorganization of the brain after partial sensory deprivation.


Assuntos
Vias Auditivas/diagnóstico por imagem , Percepção Auditiva , Imagem de Tensor de Difusão , Perda Auditiva Unilateral/diagnóstico por imagem , Audição , Plasticidade Neuronal , Pessoas com Deficiência Auditiva/psicologia , Privação Sensorial , Substância Branca/diagnóstico por imagem , Adulto , Audiometria da Fala , Vias Auditivas/fisiopatologia , Estudos de Casos e Controles , Feminino , Perda Auditiva Unilateral/fisiopatologia , Perda Auditiva Unilateral/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Valor Preditivo dos Testes , Substância Branca/fisiopatologia
6.
Neuroimage ; 197: 608-617, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31091475

RESUMO

The auditory cortex has been shown to participate in visual processing in individuals with complete auditory deprivation. However, it remains unclear whether partial hearing deprivation like single-sided deafness (SSD) leads to similar cross-modal plasticity. To investigate this, we enrolled individuals with long-term SSD, into functional MRI scans under resting-state and a visuo-spatial working memory task. Contrary to previous findings in bilateral deafness, our study revealed decreased activation in the auditory cortex in both left (LSSD) and right (RSSD) single-sided deafness compared to normal hearing controls, with statistical significance in RSSD. The degree of involvement was correlated with residual hearing ability in RSSD. These observations suggest that SSD can lead to a downward cross-modal plasticity: the more hearing ability lost, the fewer brain resources in the auditory cortex can be applied to visual tasks. In addition, the fronto-parietal cortex was observed to be less activated during the visual task in RSSD while the resting-state fMRI revealed increased functional connectivity between the fronto-parietal cortex and the auditory cortex, suggesting fronto-parietal resources may be recruited less by vision but more by hearing. The LSSD showed a similar alteration trend with RSSD, but without statistical significance. Together these findings may indicate that when hearing is partially deprived in SSD, there may be redistribution for brain resources between hearing and vision, and vision tends to allocate less resources. Our findings in this pilot study of unilateral auditory-deprived individuals enrich the understanding of cross-modal plasticity in the brain.


Assuntos
Córtex Auditivo/fisiopatologia , Perda Auditiva Unilateral/fisiopatologia , Vias Neurais/fisiopatologia , Plasticidade Neuronal/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Córtex Visual/fisiopatologia
7.
Front Aging Neurosci ; 10: 397, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30574084

RESUMO

Objective: People with presbycusis (PC) often report difficulties in speech recognition, especially under noisy listening conditions. Investigating the PC-related changes in central representations of envelope signals and temporal fine structure (TFS) signals of speech sounds is critical for understanding the mechanism underlying the PC-related deficit in speech recognition. Frequency-following responses (FFRs) to speech stimulation can be used to examine the subcortical encoding of both envelope and TFS speech signals. This study compared FFRs to speech signals between listeners with PC and those with clinically normal hearing (NH) under either quiet or noise-masking conditions. Methods: FFRs to a 170-ms speech syllable /da/ were recorded under either a quiet or noise-masking (with a signal-to-noise ratio (SNR) of 8 dB) condition in 14 older adults with PC and 13 age-matched adults with NH. The envelope (FFRENV) and TFS (FFRTFS) components of FFRs were analyzed separately by adding and subtracting the alternative polarity responses, respectively. Speech recognition in noise was evaluated in each participant. Results: In the quiet condition, compared with the NH group, the PC group exhibited smaller F0 and H3 amplitudes and decreased stimulus-response (S-R) correlation for FFRENV but not for FFRTFS. Both the H2 and H3 amplitudes and the S-R correlation of FFRENV significantly decreased in the noise condition compared with the quiet condition in the NH group but not in the PC group. Moreover, the degree of hearing loss was correlated with noise-induced changes in FFRTFS morphology. Furthermore, the speech-in-noise (SIN) threshold was negatively correlated with the noise-induced change in H2 (for FFRENV) and the S-R correlation for FFRENV in the quiet condition. Conclusion: Audibility affects the subcortical encoding of both envelope and TFS in PC patients. The impaired ability to adjust the balance between the envelope and TFS in the noise condition may be part of the mechanism underlying PC-related deficits in speech recognition in noise. FFRs can predict SIN perception performance.

8.
Acta Otolaryngol ; 138(7): 625-632, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29504434

RESUMO

OBJECTIVE: The objective of this study is to establish a reliable intraoperative auditory threshold monitoring system for ossiculoplasty surgery. DESIGN: The chirp signal of self-designed sound field earphone (SFE) was calibrated physically and psychophysically. The interaural attenuation of the SFE was tested in patients with unilateral complete deafness and contralateral normal hearing (10 patients). Self-designed SFEs were used to measure the chirp-evoked auditory steady-state responses (Chirp-ASSR) threshold of patients (14 cases and 15 ears) with conductive hearing loss after anesthesia but before surgery. RESULTS: The response threshold of Chirp-ASSR under anesthesia displayed a strong correlation with the hearing threshold for pure tones: the Pearson coefficients at various frequencies (1, 2, and 4 kHz) were 0.56 (p = .03), 0.82 (p < .001), and 0.90 (p < .001), respectively, and the intragroup correlation coefficients were 0.70 (p = 0.02), 0.90 (p < 0.001), and 0.95 (p < 0.001), respectively. The average test time was 7.0 ± 0.7 min. CONCLUSIONS: By combining Chirp-ASSR with self-designed SFE, we obtained objective multi-frequency intraoperative auditory thresholds that correlate well with the pure tone audiometry threshold. This reliable system can be applied to future intraoperative auditory threshold monitoring for ossiculoplasty surgery.


Assuntos
Limiar Auditivo , Monitorização Neurofisiológica Intraoperatória/métodos , Adulto , Audiometria de Tons Puros , Feminino , Voluntários Saudáveis , Humanos , Masculino , Procedimentos Cirúrgicos Otológicos , Adulto Jovem
9.
Microsurgery ; 36(1): 49-53, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25752505

RESUMO

Loss of long-term projection is the major disadvantage of nipple reconstruction using local flaps. We report a technique of immediate perforator flap nipple reconstruction in breast reconstruction by latissimus dorsi (LD) myocutaneous flap in patients with Poland's syndrome. From March 2007 to July 2012, 12 female patients (age range, 15-21 years) underwent breast reconstructions and immediate nipple reconstructions. A thoracodorsal artery perforator (TAP) flap was simultaneously raised on the LD muscle flap and folded by itself to form the nipple. Both the LD flap and TAP flaps survived postoperatively. The nipple projection was measured by a caliper, and the average loss was 29% by the 1-year follow-up. Eleven patients considered the aesthetic appearance of reconstructed breast and nipple to be very good or good. The immediate nipple reconstruction with TAP flap could be safely performed and results in considerable satisfaction in breast reconstruction by LD myocutaneous flap in patients with Poland's syndrome.


Assuntos
Mamoplastia/métodos , Retalho Miocutâneo , Mamilos/cirurgia , Satisfação do Paciente , Retalho Perfurante , Síndrome de Poland/cirurgia , Adolescente , Feminino , Humanos , Músculos Superficiais do Dorso/transplante , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
10.
PLoS One ; 10(12): e0144410, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26641252

RESUMO

BACKGROUND: The aim of the present study was to evaluate potential psychosocial factors that impact Chinese female breast cancer patients to select breast reconstruction (BR), and potential connection of psychosocial outcomes with their satisfaction with BR. METHODS: A total of 264 female breast cancer patients with mastectomy were recruited from 2012 to 2014. All patients were informed with BR options at their first visit. Personal and medical profiles were collected. Body image, self-esteem, depression and anxiety were assessed using validated scales. Patients who were selected to undergo BR after the first visit were followed up for six months. The same assessment was performed at 6 months post BR, and their satisfaction with BR was evaluated using the Alderman scale. Multivariate linear and logistic regressions were performed. RESULTS: Forty-seven percent of the patients (126/264) opted to undergo BR within six months after the initial visit. Multivariate logistic regression analysis revealed that self-esteem (P < 0.05), body image (P < 0.01), education level (P < 0.05), and their husband's recommendation (P < 0.05) were highly related to the patients' decision to undergo BR. In addition, multivariate linear regression analysis showed that patient satisfaction with BR was significantly associated with preoperative body image (P < 0.01), postoperative improvement in self-esteem (P < 0.01), improvement in body image (P < 0.01), reduction in depression (P < 0.05), pain (P < 0.05), and scarring (P < 0.01). CONCLUSIONS: The psychosocial factors including self-esteem and body image are highly related to selecting the BR option and post-BR satisfaction in Chinese female breast cancer patients.


Assuntos
Adaptação Psicológica , Neoplasias da Mama/psicologia , Neoplasias da Mama/cirurgia , Mamoplastia/psicologia , Mastectomia/reabilitação , Avaliação de Resultados em Cuidados de Saúde , Ansiedade , China , Emoções , Feminino , Seguimentos , Humanos , Mamoplastia/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Satisfação do Paciente , Prognóstico , Estudos Prospectivos , Autoimagem , Inquéritos e Questionários , Fatores de Tempo
11.
Ann Plast Surg ; 72(1): 121-30, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24343320

RESUMO

BACKGROUND: There is no consensus with regard to antibiotic prophylaxis usage in clean and clean-contaminated plastic and reconstructive surgery. This meta-analysis sought to assess the efficacy and safety of antibiotic prophylaxis and to determine appropriate duration of prophylaxis. METHODS: An English language literature search was conducted using PubMed and the Cochrane Collaboration for randomized controlled trials (RCTs) that evaluate the use of antibiotic prophylaxis to prevent postoperative surgical site infection (SSI) in patients undergoing clean and clean-contaminated plastic and reconstructive surgery. Data from intention-to-treat analyses were used where available. For the dichotomous data, results for each study were odds ratio (OR) with 95% confidence interval (CI) and combined for meta-analysis using the Mantel-Haenszel method or the DerSimonian and Laird method. Study quality was critically appraised by 2 reviewers using established criteria. STATA version 12 was used for meta-analyses. RESULTS: Twelve RCTs involving 2395 patients were included, of which 8 trials were considered to be of high methodological quality. Effect of antibiotic prophylaxis in plastic and reconstructive surgery was found favorable over placebo in SSI prevention (13 studies; 2449 participants; OR, 0.53; 95% CI, 0.4-0.7; P < 0.01) and the other wound complication (OWC) prevention (9 studies; 1843 participants; OR, 0.36; 95% CI, 0.15-0.84; P < 0.02). Subgroup analysis performed according to surgical wound type or the duration of prophylaxis did not modify the results except for the OWC with short-term antibiotic treatment. Compared with short-term antibiotic prophylaxis, long-term administration showed no evidence of a difference in risk of SSI (7 studies; 1012 participants; OR, 0.99; 95% CI, 0.63-1.55; P < 0.95), OWC (5 studies; 824 participants; OR, 0.92; 95% CI, 0.46-1.86; P < 0.82), and adverse event relative to antibiotic administration (3 studies; 653 participants; OR, 0.23; 95% CI, 0.01-4.92; P < 0.35). CONCLUSIONS: This meta-analysis of RCTs provides evidence supporting that antibiotic prophylaxis reduced postoperative SSI in clean plastic surgeries with high-risk factors and clean-contaminated plastic surgeries. Besides, a short-course administration regimen seemed to be of adequate efficacy and safety. High-quality prospective trials on larger scale are needed to further confirm these findings.


Assuntos
Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Procedimentos de Cirurgia Plástica , Cuidados Pré-Operatórios/métodos , Infecção da Ferida Cirúrgica/prevenção & controle , Humanos , Modelos Estatísticos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Infecção da Ferida Cirúrgica/etiologia , Resultado do Tratamento
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