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PURPOSE: The Microphone and Receiver in the ear (M&RIE) hearing aid is designed to consider the pinna cues by placing an additional microphone along with a standard receiver at the entrance of the ear canal. There is a need to clinically validate the technology using speech identification measures, as a literature shortage exists. The objective of the study was to evaluate speech identification and quality rating with hearing aids fitted with standard and M&RIE receivers. METHOD: Twenty individuals (mean ± SD age being 34.10 ± 11.9 years) with mild-to-moderately severe sensorineural hearing loss were divided into two groups: naïve and experienced. Their speech identification obtained using the receiver in the ear hearing aid compatible with standard and M&RIE receivers were compared. The study assessed speech identification in quiet using ten sentences, calculated SNR-50 using the Spearman-Karber equation, and used an 11-point scale for self-perceived quality rating. RESULTS: The study analyzed data using SPSS and found no significant difference between naive and experienced hearing aid users in quiet and SNR-50 conditions (p > 0.05). However, naive users rated higher in clarity, naturalness, pleasantness, and overall impression of standard receiver settings. Across different receiver settings, both naïve and experienced groups revealed better speech identification with the M&RIE receiver for both SIS (p < 0.05) and SNR-50 (p < 0.05) measures. CONCLUSION: The study found that placing a third microphone in the ear canal improves speech identification and quality rating in both naïve and experienced users, with pinna and ear canal resonance playing a crucial role in prescribing hearing aid gain.
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Auxiliares de Audição , Perda Auditiva Neurossensorial , Percepção da Fala , Humanos , Masculino , Adulto , Feminino , Perda Auditiva Neurossensorial/reabilitação , Perda Auditiva Neurossensorial/fisiopatologia , Pessoa de Meia-Idade , Adulto JovemRESUMO
In the present study, we investigated the major histocompatibility complex (MHC)-B haplotypes diversity of Sri Lankan indigenous chickens from three different geographical sites consisting of highly mixed populations using 90 SNPs in the MHC-B region. A total of 48 haplotypes were identified. Those included 37 novel haplotypes and 11 previously identified 'standard' haplotypes. The MHC-linked marker, LEI0258, had 23 alleles showing less diversity than defined by MHC-B SNP haplotypes. Among those identified haplotypes, five standard haplotypes-BSNP-O02, BSNP-M01, BSNP-A04, BSNP-K03, BSNP-T04-were most commonly observed, suggesting past introgression of imported breeds. Comparison of the MHC-B haplotypes of Sri Lankan and four other global populations with previously defined haplotypes indicated the sharing of 23 standard haplotypes with common origins. Novel haplotypes are population-specific and not shared among the geographical boundaries. Backyard indigenous chickens are unselected, highly crossbred, and generally thrive under dynamic environmental conditions. Hence free-range production systems may be responsible for maintaining high diversity in the MHC-B region with novel haplotypes.
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Proteínas Aviárias/genética , Galinhas/genética , Variação Genética , Polimorfismo de Nucleotídeo Único , Animais , Complexo Principal de Histocompatibilidade , Sri LankaRESUMO
Protein cross-linking and radiolytic footprinting coupled with high-resolution mass spectrometry were used to examine the structure of PsbP and PsbQ when they are bound to Photosystem II. In its bound state, the N-terminal 15-amino-acid residue domain of PsbP, which is unresolved in current crystal structures, interacts with domains in the C terminus of the protein. These interactions may serve to stabilize the structure of the N terminus and may facilitate PsbP binding and function. These interactions place strong structural constraints on the organization of PsbP when associated with the Photosystem II complex. Additionally, amino acid residues in the structurally unresolved loop 3A domain of PsbP ((90)K-(107)V), (93)Y and (96)K, are in close proximity (≤ 11.4 Å) to the N-terminal (1)E residue of PsbQ. These findings are the first, to our knowledge, to identify a putative region of interaction between these two components. Cross-linked domains within PsbQ were also identified, indicating that two PsbQ molecules can interact in higher plants in a manner similar to that observed by Liu et al. [(2014) Proc Natl Acad Sci 111(12):4638-4643] in cyanobacterial Photosystem II. This interaction is consistent with either intra-Photosystem II dimer or inter-Photosystem II dimer models in higher plants. Finally, OH(â¢) produced by synchrotron radiolysis of water was used to oxidatively modify surface residues on PsbP and PsbQ. Domains on the surface of both protein subunits were resistant to modification, indicating that they were shielded from water and appear to define buried regions that are in contact with other Photosystem II components.
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Complexo de Proteína do Fotossistema II/química , Spinacia oleracea/enzimologia , Reagentes de Ligações Cruzadas , Cristalografia por Raios X , Hidróxidos/química , Complexo de Proteína do Fotossistema II/metabolismo , Pegadas de Proteínas/métodos , Estrutura Quaternária de Proteína , Estrutura Terciária de ProteínaRESUMO
We have used protein cross-linking with the zero-length cross-linker 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide, and radiolytic footprinting coupled with high-resolution tandem mass spectrometry, to examine the structure of higher-plant PsbO when it is bound to Photosystem II. Twenty intramolecular cross-linked residue pairs were identified. On the basis of this cross-linking data, spinach PsbO was modeled using the Thermosynechococcus vulcanus PsbO structure as a template, with the cross-linking distance constraints incorporated using the MODELLER program. Our model of higher-plant PsbO identifies several differences between the spinach and cyanobacterial proteins. The N-terminal region is particularly interesting, as this region has been suggested to be important for oxygen evolution and for the specific binding of PsbO to Photosystem II. Additionally, using radiolytic mapping, we have identified regions on spinach PsbO that are shielded from the bulk solvent. These domains may represent regions on PsbO that interact with other components, as yet unidentified, of the photosystem.
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Reagentes de Ligações Cruzadas , Cianobactérias/metabolismo , Complexo de Proteína do Fotossistema II/química , Proteínas de Plantas/química , Radiólise de Impulso , Spinacia oleracea/metabolismo , Sequência de Aminoácidos , Cristalografia por Raios X , Cianobactérias/crescimento & desenvolvimento , Espectrometria de Massas , Modelos Moleculares , Complexo de Proteína do Fotossistema II/metabolismo , Proteínas de Plantas/metabolismo , Ligação Proteica , Conformação Proteica , Pegadas de Proteínas , Homologia de Sequência de Aminoácidos , Spinacia oleracea/crescimento & desenvolvimento , SíncrotronsRESUMO
MAIN CONCLUSION: Recent investigations have provided important new insights into the structures and functions of the extrinsic proteins of Photosystem II. This review is an update of the last major review on the extrinsic proteins of Photosystem II (Bricker et al., Biochemistry 31:4623-4628 2012). In this report, we will examine advances in our understanding of the structure and function of these components. These proteins include PsbO, which is uniformly present in all oxygenic organisms, the PsbU, PsbV, CyanoQ, and CyanoP proteins, found in the cyanobacteria, and the PsbP, PsbQ and PsbR proteins, found in the green plant lineage. These proteins serve to stabilize the Mn4CaO5 cluster and optimize oxygen evolution at physiological calcium and chloride concentrations. The mechanisms used to perform these functions, however, remain poorly understood. Recently, important new findings have significantly advanced our understanding of the structures, locations and functions of these important subunits. We will discuss the biochemical, structural and genetic studies that have been used to elucidate the roles played by these proteins within the photosystem and their locations within the photosynthetic complex. Additionally, we will examine open questions needing to be addressed to provide a coherent picture of the role of these components within the photosystem.
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Complexo de Proteína do Fotossistema II/química , Complexo de Proteína do Fotossistema II/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Clorófitas/metabolismo , Cianobactérias/metabolismo , Ligação de Hidrogênio , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
In the title mol-ecule, C17H15ClN4S, the benzene rings form dihedral angles of 16.6â (1) and 77.2â (1)° with the triazole ring. The dihedral angle between the benzene rings is 86.6â (1)°. In the crystal, pairs of N-Hâ¯S hydrogen bonds form inversion dimers with graph-set notation R 2 (2)(8). Weak C-Hâ¯S hydrogen bonds link these dimers into layers parallel to (100). Weak intra-molecular C-Hâ¯S and C-Hâ¯N contacts are observed.
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In the title compound, C9H10N4OS, the dihedral angle between the benzene and 1H-1,2,4-triazole-5(4H)-thione rings is 67.51â (16)°. In the crystal, mol-ecules are liked via N-Hâ¯O hydrogen bonds, forming chains along the c-axis direction. The chains are linked via O-Hâ¯S hydrogen bonds, forming corrugated layers lying parallel to the bc plane. The layers are linked via N-Hâ¯N and N-Hâ¯S hydrogen bonds, forming a three-dimensional network.
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In the title compound, C10H9ClN4S, the dihedral angle between the mean planes of the phenyl and 1H-1,2,4-triazole-5(4H)-thione rings is 25.3â (9)°. The latter ring is essentially planar, with maximum deviations of 0.010 and -0.010â Å for the ring N atom in the 4-position and ring C atom bearing the methyl group, respectively. An intra-molecular C-Hâ¯S contact occurs. In the crystal, pairs of weak N-Hâ¯S inter-actions link the mol-ecules into inversion dimers in the ac plane, forming R 2 (2)(8) graph-set motifs. In addition, weak π-π inter-actions [centroid-centroid distances = 3.3463â (14) and 3.6127â (13)Å] are observed.
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OBJECTIVE: The study aimed to compare ipsilateral and contralateral electrically evoked stapedial reflex thresholds in children with a unilateral cochlear implant surgically implanted either through Veria or posterior tympanotomy approaches. METHODS: Forty-nine children using cochlear implants were studied, of whom 27 underwent the Veria approach and 22 underwent the posterior tympanotomy approach. The electrically evoked stapedius reflex thresholds were measured ipsilaterally and contralaterally by stimulating four equally spaced electrodes. RESULTS: The ipsilateral electrically evoked stapedius reflex threshold was absent in all four electrodes in the children implanted using the Veria approach. However, the ipsilateral electrically evoked stapedius reflex threshold was present in 70 per cent of the children implanted using the posterior tympanotomy approach. The contralateral electrically evoked stapedius reflex threshold was present in most of the children for both surgical approaches. CONCLUSION: The presence of the ipsilateral electrically evoked stapedius reflex threshold varies depending on the surgical technique used for cochlear implantation. However, contralateral reflexes are present in the majority of children using cochlear implants, irrespective of the surgical approach.
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Lyme disease, caused by the bacterium Borrelia burgdorferi, is the most common tick-borne illness in the United States. Despite the rise in Lyme disease incidence, there is no vaccine against B. burgdorferi approved for human use. Little is known about the immune correlates of protection needed to prevent Lyme disease. In this work, a mouse model was used to characterize the immune response and compare the protection provided by two USDA-approved vaccines for use in canines: Duramune (bacterin vaccine) and Vanguard crLyme (subunit vaccine composed of two outer surface proteins, OspA and OspC). C3H/HeNCrl mice were immunized with two doses of either Duramune or Vanguard, and immune responses and protection against B. burgdorferi were assessed in short (35 days) and long-term (120 days) studies. Flow cytometry, ELISPOT detection of antibody-producing cells, and antibody affinity studies were performed to identify correlates of vaccine-mediated protection. Both vaccines induced humoral responses, with high IgG titers against B. burgdorferi. However, the levels of anti-B. burgdorferi antibodies decayed over time in Vanguard-vaccinated mice. While both vaccines triggered the production of antibodies against both OspA and OspC, antibody levels against these proteins were also lower in Vanguard-vaccinated mice 120 days post-vaccination. Both vaccines only provided partial protection against B. burgdorferi at the dose used in this model. The protection provided by Duramune was superior to Vanguard 120 days post-vaccination, and was characterized by higher antibody titers, higher abundance of long-lived plasma cells, and higher avidity antibodies than Vanguard. Overall, these studies provide insights into the importance of the humoral memory response to veterinary vaccines against Lyme disease and will help inform the development of future human vaccines.
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OBJECTIVE: To investigate the effect of pre-transition duration on acoustic change complex (ACC) for speech and tonal stimulus. DESIGN: Cortical potentials were recorded for consonant-vowel syllable and tonal complex stimuli with varying pre-transition durations. STUDY SAMPLE: Ten individuals (three male and seven female) in the age range from 18 to 26 years, with normal hearing sensitivity, participated in the study. RESULTS: The results revealed that a minimum pre-transition duration of 100 ms for tonal stimulus (with spectral change) and 80 ms for consonant-vowel syllable is necessary in order to elicit ACC. The latency of N1(1) and P2(1), which is the response for change within the ongoing stimulus, increased with increase in pre-transition duration. The amplitude of the evoked responses did not show any significant change. CONCLUSIONS: It was found that minimum pre-transition duration required in eliciting ACC for speech and non-speech stimulus is not same. The speech stimulus required lesser duration of pre-transition than non-speech stimulus. Further studies regarding the acoustic aspects of sound on CAEP in isolation are warranted.
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Estimulação Acústica/métodos , Potenciais Evocados Auditivos , Acústica da Fala , Percepção da Fala , Adolescente , Adulto , Análise de Variância , Audiometria de Tons Puros , Audiometria da Fala , Limiar Auditivo , Eletroencefalografia , Feminino , Humanos , Modelos Lineares , Masculino , Tempo de Reação , Espectrografia do Som , Fatores de Tempo , Adulto JovemRESUMO
In the title mol-ecule, C11H12N4S2, the dihedral angle between the triazole and benzene rings is 21.31â (5)°. A weak intra-molecular C-Hâ¯S hydrogen bond generates an S(6) ring motif. In the crystal, pairs of N-Hâ¯S hydrogen bonds form inversion dimers. In addition, π-π inter-actions are observed between the benzene rings, with a centroid-centroid separation of 3.7599â (11)â Å.
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In the title mol-ecule, C10H12N4SO, the triazole ring forms a dihedral angle of 73.0â (5)° with the benzene ring. The meth-oxy group is approximtely coplanar with the benzene ring with a C C-O-Cmeth-yl torsion angle of 4.7â (3)°. In the crystal, N-Hâ¯S hydrogen bonds connect pairs of inversion-related mol-ecules, which are in turn connected by N-Hâ¯N hydrogen bonds into chains of rings along [010]. Weak C-Hâ¯O hydrogen bonds connect these chains into a two-dimensional network parallel to (-102).
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AIM & OBJECTIVES: The aim of the present study was in three-fold: (a) to analyze the factors that affect the hearing aid (HA) continuation/discontinuation in children with unilateral cochlear implant (CI); (b) to understand the parent's knowledge on binaural benefit; and (c) to find out any association between the hearing aid continuation/discontinuation with implant age and/or with duration of hearing aid use prior to surgery. METHOD: The study involved 97 participants who were parents of children with unilateral cochlear implants. A questionnaire with 30 questions was used to explore HA use and certain related perceptions, and a Likert scale was used for ranking responses. RESULTS: & Discussion: Only 31.9% children were using HA consistently, post CI activation The principal factor for discontinuation of HA was its helpfulness prior CI whereas children wore HA only because they were instructed during counseling. Participants did not perceive functional benefit bimodal fitting due to superiority of CI performance and poor residual hearing. Also, it was found that there is no association between neither the implant age nor duration of HA use before CI with the HA continuation/discontinuation on Chi-square test. CONCLUSIONS: The results suggest a need for structured comprehensive counseling and demonstration sessions to educate parents on binaural hearing to gain maximum benefits from non-invasive bimodal fitting.
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Implante Coclear , Implantes Cocleares , Auxiliares de Audição , Percepção da Fala , Criança , Humanos , Percepção da Fala/fisiologia , Implante Coclear/métodos , Audição/fisiologiaRESUMO
Hypertrophic scarring (HTS) is an aberrant form of wound healing that is associated with excessive deposition of extracellular matrix and connective tissue at the site of injury. In this review article, we provide an overview of normal (acute) wound healing phases (hemostasis, inflammation, proliferation, and remodeling). We next discuss the dysregulated and/or impaired mechanisms in wound healing phases that are associated with HTS development. We next discuss the animal models of HTS and their limitations, and review the current and emerging treatments of HTS.
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Cicatriz Hipertrófica , Animais , Cicatriz Hipertrófica/patologia , Cicatrização , Modelos Animais , Inflamação , Matriz Extracelular/patologiaRESUMO
Older adults with hearing loss face many challenges in day to day communication. Although hearing aids come with many technologies and features, the use and benefit are still not as expected. The possible non-audiological factors that can influence the benefit from hearing aid remain uncertain. The present study focuses on assessing the influence of attitude towards loss of hearing and personality on the perceived hearing aid benefit in older adults. Attitude towards loss of hearing questionnaire (ALHQ) and Eysenck Personality Inventory (EPI) were administered on 42 older adults having mild to moderately-severe sensorineural hearing loss, who were naïve users of hearing aid. Two months later, International Outcome Inventory-Hearing Aids (IOI-HA) scores and the number of hours of hearing aid use through data logging of hearing aid were noted. Individuals with extrovert trait of personality and with acceptance towards hearing loss had higher number of hours of hearing aid usage and higher IOI-HA scores. Discussion: The individuals with extrovert personality, positive attitude towards hearing loss tends to depend on the amplification device for better communication and involve themselves more in social interaction. Poor acceptance and negative social or emotional reaction towards hearing loss can have a greater impact on hearing aid use and benefit. The present study highlights the importance of assessing the attitude and personality in older adults with hearing loss before fitting the hearing aid. These measures can be focussed during counselling about the realistic expectation of outcome from the hearing aid.
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Cardiac tissue engineering using cells, scaffolds or signaling molecules is a promising approach for replacement or repair of damaged myocardium. This study addressed the contemporary need for a conductive biomimetic nanocomposite scaffold for cardiac tissue engineering by examining the use of a gold nanoparticle-incorporated porcine cholecystic extracellular matrix for the same. The scaffold had an electrical conductivity (0.74 ± 0.03 S/m) within the range of native myocardium. It was a suitable substrate for the growth and differentiation of cardiomyoblast (H9c2) as well as rat mesenchymal stem cells to cardiomyocyte-like cells. Moreover, as an epicardial patch, the scaffold promoted neovascularisation and cell proliferation in infarcted myocardium of rats. It was concluded that the gold nanoparticle coated cholecystic extracellular matrix is a prospective biomaterial for cardiac tissue engineering.
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Nanopartículas Metálicas , Alicerces Teciduais , Animais , Condutividade Elétrica , Matriz Extracelular , Ouro/química , Miocárdio , Miócitos Cardíacos , Estudos Prospectivos , Ratos , Suínos , Engenharia Tecidual , Alicerces Teciduais/químicaRESUMO
BACKGROUND: Preterm infants can have many neurological problems. An enormous amount of fetal brain development occurs during the last trimester of pregnancy. They include myelination, glial cell migration and the development of a complex gyral pattern. The brain doesn't show the normal growth after birth in preterm infants. Brainstem auditory evoked potentials (BAEPs) are a noninvasive neurophysiologic assessment of brainstem maturation in babies. METHODS: BAEPs in 25 preterm and 25 full-term infants were considered for the study. Infants having history of birth trauma, metabolic disorders or intracranial infection were excluded. BAEP waveforms (absolute and interpeak latencies) were recorded and analyzed. Student t test was used to analyze the data thus acquired. RESULTS: Analysis of data revealed a significant increase in latency of BAEP waveform V (P<0.05). Other latencies and interpeak latencies of BAEP waveforms were comparable. CONCLUSION: The preterm infants have a prolonged latency of BAEP waveform V suggestive of a retarded myelination of the central auditory pathway. Thus BAEP could be a useful electrophysiological test to assess neuronal myelination and maturation in preterm infants.
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Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Recém-Nascido Prematuro/fisiologia , Humanos , Recém-Nascido , Tempo de ReaçãoRESUMO
Purpose: The mechanism underlying primordial follicle activation is poorly understood. In this study, in-vitro culture and subsequent xenotransplantation were conducted to determine whether testosterone promotes the activation of porcine primordial follicles. Methods: Prepubertal porcine ovarian cortical strips containing primordial follicles were cultured in the presence of testosterone for 7 days, and subsequently transplanted to immunodeficient mice for 2 months. After culture and transplantation, development of follicles was examined histologically. The presence of androgen receptors in oocytes was assessed by use of western blot and immunohistochemical analyses. Results: Testosterone at 10-6 m induced the primordial follicle transition to the intermediate (19 ± 4%) and primary (3 ± 1%) stages after 7-day culture, while 56 ± 5% of primordial follicles remained in the initial pool. Higher concentrations, above 10-5 m, or lower concentrations, below 10-6 m, did not induce follicle transition to the primary stage. After 7-day culture with 10-6 m testosterone, ovarian cortical strips were transplanted to immunodeficient mice. Some of the follicles developed to the secondary (15 ± 3%) and antral (10 ± 3%) stages, whereas 44 ± 7% of primordial follicles remained in the initial pool. In the culture experiment, estradiol-17ß (10-7-10-5 m) had no significant effect on follicle activation. The androgen receptor antagonist, cyproterone acetate, inhibited the stimulatory effect of testosterone on primordial follicle activation, suggesting an androgen receptor-mediated action of testosterone. Western blot and immunohistochemical analyses revealed that androgen receptors were present in the oocytes of primordial follicles. Conclusions: These results suggest that testosterone at 10-6 m promotes the activation of porcine primordial follicles in vitro through the androgen receptors in the oocytes.
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Coral skeletons are materials composed of inorganic aragonitic fibres and organic molecules including proteins, sugars and lipids that are highly organized to form a solid biomaterial upon which the animals live. The skeleton contains tens of proteins, all of which are encoded in the animal genome and secreted during the biomineralization process. While recent advances are revealing the functions and evolutionary history of some of these proteins, how they are spatially arranged in the skeleton is unknown. Using a combination of chemical cross-linking and high-resolution tandem mass spectrometry, we identify, for the first time, the spatial interactions of the proteins embedded within the skeleton of the stony coral Stylophora pistillata. Our subsequent network analysis revealed that several coral acid-rich proteins are invariably associated with carbonic anhydrase(s), alpha-collagen, cadherins and other calcium-binding proteins. These spatial arrangements clearly show that protein-protein interactions in coral skeletons are highly coordinated and are key to understanding the formation and persistence of coral skeletons through time.