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1.
Artigo em Inglês | MEDLINE | ID: mdl-38659259

RESUMO

Brain-related disorders include neuroinflammation, neurodegenerative disorders, and demyelination, which ultimately affect the quality of life of patients. Currently, brain-related disorders represent the most challenging health problem worldwide due to complex pathogenesis and limited availability of drugs for their management. Further, the available pharmacotherapy accompanies serious side effects, therefore, much attention has been directed toward the development of alternative therapy derived from natural sources to treat such disorders. Recently, flavonoids, natural phytochemicals, have been reported as a treatment option for preventing brain aging and disorders related to this. Among these flavonoids, dietary luteolin, a flavone, is found in many plant products such as broccoli, chamomile tea, and honeysuckle bloom having several pharmacological properties including neuroprotective activities. Therefore, the objective of this paper is to compile the available literature regarding the neuroprotective potential of luteolin and its mechanism of action. Luteolin exerts notable anti-inflammatory, antioxidant, and antiapoptotic activity suggesting its therapeutic efficacy in different neurological disorders. Numerous in-vivo and in-vitro experiments have revealed that luteolin exhibits neuroprotective potential via up-regulating the ER/ERK, PI3AKT, Nrf2 pathways and down-regulating the MAPK/JAK2STAT and NFκB pathways. Taking into account of available facts regarding the neuroprotective efficacy of luteolin, the current study highlights the beneficial effects of luteolin for the prevention, management, and treatment of different neurological disorders. Thus, luteolin can be considered an alternative for the development of new pharmacophores against various brain-related disorders.

2.
Angew Chem Int Ed Engl ; 63(11): e202401234, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38252519

RESUMO

Flexible thermoelectric devices of nanomaterials have shown a great potential for applications in wearable to remotely located electronics with desired shapes and geometries. Continuous powering up the low power flexible electronics is a major challenge. We are reporting a flexible thermoelectric module prepared from silver telluride (Ag2 Te) nanowires (NWs), which are chemically transformed from uniquely synthesized and scalable tellurium (Te) NWs. Conducting Ag2 Te NWs composites have shown an ultralow total thermal conductivity ~0.22 W/mK surpassing the bulk melt-grown Ag2 Te ~1.23 W/mK at ~300 K, which is attributed to the nanostructuring of the material. Flexible thermoelectric device consisting of 4 legs (n-type) of Ag2 Te NWs on polyvinylidene fluoride membrane displays a significant output voltage (Voc ) ~2.3 mV upon human touch and Voc ~18 mV at temperature gradient, ΔT ~50 K, which shows the importance of NWs based flexible thermoelectric devices to power up the low power wearable electronics.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38243959

RESUMO

Parkinson's disease (PD), the most common brain-related neurodegenerative disorder, is comprised of several pathophysiological mechanisms, such as mitochondrial dysfunction, neuroinflammation, aggregation of misfolded alpha-synuclein, and synaptic loss in the substantia nigra pars compacta region of the midbrain. Misfolded alpha-synuclein, originating from damaged neurons, triggers a series of signaling pathways in both glial and neuronal cells. Activation of such events results in the production and expression of several proinflammatory cytokines via the activation of the nuclear factor κB (NF-κB) signaling pathway. Consequently, this cascade of events worsens the neurodegenerative processes, particularly in conditions, such as PD and synucleinopathies. Microglia, astrocytes, and neurons are just a few of the many cells and tissues that express the NF-κB family of inducible types of transcription factors. The dual role of NF-κB activation can be crucial for neuronal survival, although the classical NF-κB pathway is important for controlling the generation of inflammatory mediators during neuroinflammation. Modulating NF-κB-associated pathways through the selective action of several agents holds promise for mitigating dopaminergic neuronal degeneration and PD. Several naturally occurring compounds in medicinal plants can be an effective treatment option in attenuating PD-associated dopaminergic neuronal loss via selectively modifying the NF-κB-mediated signaling pathways. Recently, flavonoids have gained notable attention from researchers because of their remarkable anti-neuroinflammatory activity and significant antioxidant properties in numerous neurodegenerative disorders, including PD. Several subclasses of flavonoids, including flavones, flavonols, isoflavones, and anthocyanins, have been evaluated for neuroprotective effects against in vitro and in vivo models of PD. In this aspect, the present review highlights the pathological role of NF-κB in the progression of PD and investigates the therapeutic potential of natural flavonoids targeting the NF-κB signaling pathway for the prevention and management of PD-like manifestations with a comprehensive list for further reference. Available facts strongly support that bioactive flavonoids could be considered in food and/or as lead pharmacophores for the treatment of neuroinflammation-mediated PD. Furthermore, natural flavonoids having potent pharmacological properties could be helpful in enhancing the economy of countries that cultivate medicinal plants yielding bioactive flavonoids on a large scale.

4.
Ear Hear ; 45(1): 227-238, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37608435

RESUMO

OBJECTIVES: Stimulus and recording parameters are pivotal for shaping the ocular vestibular-evoked myogenic potential (oVEMP). In the last decade, several attempts were made to identify the optimum electrode placement site to improve the oVEMP responses. A vast majority of these found larger response amplitudes for alternate electrode montages like belly-tendon (BT), chin-referenced (CR), and/or sternum-referenced montages than the clinically used infra-orbital montage. However, no study has yet compared all alternate electrode montages in a simultaneous recording paradigm to eliminate other confounding factors. Also, no study has compared all of them for their test-retest reliability, waveform morphology, and signal-to-noise ratio. Therefore, the decision on which among these electrode montages is best suited for oVEMP acquisition remains opaque. The present study aimed to investigate the effects of various electrode montages on oVEMP's response parameters and to determine the test-retest reliability of each of these in clinically healthy individuals using a simultaneous recording paradigm. DESIGN: This study had a within-subject experimental design. Fifty-five young healthy adults (age range: 20-30 years) underwent contralateral oVEMP recording using infra-orbital, BT, chin-referenced, and sternum-referenced electrode montages simultaneously using a four-channel evoked potential system. RESULTS: BT montage had a significantly shorter latency, larger amplitude, higher signal-to-noise ratio, and better morphology than other alternate montages ( p < 0.008). Further, all electrode montages of the current study showed fair/moderate to excellent test-retest reliability. CONCLUSIONS: By virtue of producing significantly better response parameters than the other electrode montages, BT montage seems better suited to the recording of oVEMP than the known electrode montages thus far.


Assuntos
Potenciais Evocados Miogênicos Vestibulares , Vestíbulo do Labirinto , Adulto , Humanos , Adulto Jovem , Reprodutibilidade dos Testes , Potenciais Evocados Miogênicos Vestibulares/fisiologia , Eletrodos , Razão Sinal-Ruído
5.
Front Neurol ; 14: 1288150, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38020643

RESUMO

Introduction: Benign paroxysmal positional vertigo (BPPV) involving the posterior canal is more common than other canals; however, simultaneous involvement of multiple canals can be seen up to 20% of all BPPV cases. The diagnosis and management of multiple canal BPPV can be quite challenging due to the complexity of findings. Therefore, this systematic review and meta-analysis aimed at unveiling the most effective repositioning strategy for the treatment of multiple canal BPPV. Methods: A literature search through PubMed, Scopus, and Web of Science databases was conducted using search terms such as BPPV, multiple canals, bilateral BPPV, repositioning maneuvers etc. After duplicate removal, the retained articles underwent various stages of elimination by two independent reviewers, and a third reviewer resolved the discrepancy between them. Results: A total of 22 articles were included in the systematic review. These publications documented 5,196 patients diagnosed with BPPV, of which 513 had multiple canal BPPV. Of 295 individuals with multiple canal BPPV, 58.9% were effectively treated in 1 session, whereas 18.3 and 4.4% achieved a symptom-free state after two and three sessions, respectively. Failure of treatment using repositioning maneuvers was found in 18.4%. Possible implications: This study offers insight into the real world of BPPV management in single and multiple canal BPPV. It is evident that repositioning maneuvers provide rapid and long-lasting relief of BPPV in most single canal BPPV patients; however, multiple canal BPPV often requires repeated treatment, and the risk of recurrence is higher in this variety than the single canal BPPV.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37817521

RESUMO

Recently, Parkinson's disease (PD) has become a remarkable burden on families and society with an acceleration of population aging having several pathological hallmarks such as dopaminergic neuronal loss of the substantia nigra pars compacta, α-synucleinopathy, neuroinflammation, autophagy, last but not the least astrogliosis. Astrocyte, star-shaped glial cells perform notable physiological functions in the brain through several molecular and cellular mechanisms including nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. It has been well established that the downregulation of the astrocytic Nrf2 signaling pathway plays a crucial role in the pathogenesis of PD because it is a master regulator of cellular defense mechanism along with a regulator of numerous detoxifying and antioxidant enzymes gene expression. Fascinatingly, upregulation of the astrocytic Nrf2 signaling pathway attenuates the degeneration of nigrostriatal neurons, restores neuronal proliferation, rejuvenates astrocytic functions, and exhibits neuroprotective effects via numerous cellular and molecular mechanisms in the PD-like brain of the experimental animal. Here, we discuss the numerous in-vitro and in-vivo studies that evaluate the neuroprotective potential of the astrocytic Nrf2 signaling pathway against experimentally-induced PD-like manifestation. In conclusion, based on available preclinical reports, it can be assumed that the astrocytic Nrf2 signaling pathway could be an alternative target in the drug discovery process for the prevention, management, and treatment of PD.

7.
Int J Audiol ; 62(7): 635-643, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37393930

RESUMO

OBJECTIVE: The present study aimed to investigate the findings of cervical, ocular and masseter vestibular evoked myogenic potentials (cVEMP, oVEMP and mVEMP) among Multiple sclerosis (MS) and correlate with clinical and MRI findings. DESIGN: Standard group comparison research design. STUDY SAMPLE: Individuals with relapsing-remitting MS (n = 45) and age-sex-matched controls (n = 45) were the participants. All of them underwent case history, neurological examination, cVEMP, oVEMP and mVEMP testing. MRI was obtained only for MS participants. RESULTS: Abnormal result on at least one vestibular evoked myogenic potential (VEMP) sub-type was evidenced in 95.56% of participants whereas, unilateral or bilateral abnormal result on all three VEMP sub-types was observed in 60% of participants. The mVEMP abnormality was higher (82.22%) than cVEMP (75.56%) and oVEMP (75.56%) abnormalities but the differences were not significant (p > 0.05). There was no significant association of VEMP abnormalities with the presence of the brainstem symptoms, the brainstem signs, or the MRI lesions (p > 0.05). In the MS group, 38% had normal brainstem MRI; however, mVEMP, cVEMP and oVEMP abnormalities were evidenced in 82.4%, 64.7% and 52.94%, respectively. CONCLUSIONS: Among the three VEMP sub-types, mVEMP appears to be of greater value in identifying silent brainstem dysfunction undetected by clinical and MRI findings in the MS population.


Assuntos
Esclerose Múltipla , Potenciais Evocados Miogênicos Vestibulares , Humanos , Potenciais Evocados Miogênicos Vestibulares/fisiologia , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/patologia , Tronco Encefálico , Imageamento por Ressonância Magnética
8.
3 Biotech ; 13(7): 247, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37366498

RESUMO

Phycobiliproteins is a family of chromophore-containing proteins having light-harvesting and antioxidant capacity. The phycocyanin (PC) is a brilliant blue coloured phycobiliprotein, found in rod structure of phycobilisome and has been widely studied for their therapeutic and fluorescent properties. In the present study, the hexameric assembly structure of phycocyanin (Syn-PC) from Synechococcus Sp. R42DM is characterized by X-ray crystallography to understand its light-harvesting and antioxidant properties. The crystal structure of Syn-PC is solved with 2.15 Å resolution and crystallographic R-factors, Rwork/Rfree, 0.16/0.21. The hexamer of Syn-PC is formed by heterodimer of two polypeptide chains, namely, α- and ß-subunits. The structure is analysed at atomic level to reveal the chromophore microenvironment and possible light energy transfer mechanism in Syn-PC. The chromophore arrangement in hexamer, deviation angle and distance between the chromophore contribute to the energy transfer efficiency of protein. The structural attributes responsible for the antioxidant potential of Syn-PC are recognized and annotated on its 3-dimensional structure. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03665-1.

9.
Int J Biol Macromol ; 242(Pt 2): 124810, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37182622

RESUMO

Hot-springs are regarded as the best source of industrially significant biocules and one of the unique locations for extremophiles. The α-amylase is one of the most important enzymes used in starch consuming industries, where the need of thermostability is paramount. In this study, the full metagenome sequences obtained from the soil of Tuwa hot-spring (Gujarat, India) were examined for the presence of several thermostable enzymes using bioinformatic techniques. The whole gene sequence for α-amylase was found from the metagenome. The α-amylase gene was amplified, cloned, and expressed in Escherichia coli and further characterized in vitro. The rm-α-amylase was found optimally active at 60 °C and at pH 6.0 and showed significantly high activity in 0.1 mM Co2+ as well as in other heavy metal ions without any effect on its thermostability. Apart from α-amylase activity the purified rm-α-amylase was also shown to hydrolyse agar, xylan, pectin, alginate and cellulose. To our knowledge, this is the first report of a new, multifunctional, thermostable amylase that was discovered from the hot-spring metagenomes. Owing to their multifunctionality, resilience towards high temperature and heavy metal ions, stability with solvents, additives and inhibitors, rm-α-amylase can be exploited for a variety of biotechnological applications.


Assuntos
Metagenoma , alfa-Amilases , alfa-Amilases/química , Estabilidade Enzimática , Índia , Concentração de Íons de Hidrogênio , Temperatura
10.
Curr Mol Med ; 23(9): 889-900, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37254536

RESUMO

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder, and its consequences severely influence the quality of a patient's life and mobility. PD is characterized by bradykinesias with tremors and/or rigidity. Pathophysiologically, PD is associated with the gradual degeneration of dopaminergic neurons in the substantia nigra pars compacta of the midbrain, neuroinflammation, increased accumulation of the alpha (α)-synuclein, overburden of oxidative stress, and mitochondrial dysfunction. To date, there are no effective therapies with underlying shreds of evidence that alters the progression of PD. Exendin-4, a glucagon-like peptide 1 (GLP-1) receptor agonist, has gained attention for its tremendous neuroprotective potential against numerous neurodegenerative disorders, including PD. Further, several pieces of research evidence have suggested the beneficial role of Exendin-4 in PD-like experimental models. The present review article highlights the preclinical and clinical evidence of the therapeutic benefits of Exendin-4 against PD. Exendin-4 reverses the PD-like symptoms in experimental animals by dramatically minimizing the loss of dopaminergic neuronal and accumulation of α-synuclein in the PD-like brain. Further, it also reduces the mitochondrial toxicity and expression of pro-inflammatory mediators such as tumor necrosis factor (TNF)-α and interleukin (IL)-1ß. These observations designate that Exendin-4 is a multifactorial compound that could be considered a safe, effective, and new ingredient for developing clinically useful pharmacotherapy for managing PD-like manifestations.


Assuntos
Fármacos Neuroprotetores , Doença de Parkinson , Animais , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/diagnóstico , Doença de Parkinson/metabolismo , Exenatida/farmacologia , Exenatida/metabolismo , Exenatida/uso terapêutico , Encéfalo/metabolismo , Estresse Oxidativo , Neurônios Dopaminérgicos/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico
11.
Ear Hear ; 44(5): 940-948, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36859775

RESUMO

OBJECTIVES: A recently devised parameter of vestibular-evoked myogenic potential (VEMP) based on the principles of frequency tuning is the inter-frequency amplitude ratio (IFAR). It refers to the ratio of the amplitude of 1000 Hz tone burst evoked VEMP to 500 Hz evoked tone burst. A pathology like Meniere's disease changes the frequency response and alters the frequency tuning of the otolith organs. Because IFAR is based on the principle of frequency tuning of VEMP, it is likely to help identify Meniere's disease. Few studies in the last decade have investigated the utility of IFAR in identifying Meniere's disease. However, a systematic review and a meta-analysis on IFAR in Meniere's disease are lacking. The present study investigates whether the IFAR of VEMP helps identify Meniere's disease and differentiates it from healthy ears and other vestibular pathologies. DESIGN: The present study is a systematic review and a meta-analysis. The studies investigating the IFAR of cervical and ocular VEMPs in Meniere's disease, healthy controls, and other vestibular pathologies were searched across research databases such as PubMed, Science Direct, and Scopus. The search strategy was developed using the PICO (population, intervention, comparison, and outcomes) format, and Medical Subject Headings (MeSH) terms and Boolean operators were employed. The systematic review was performed using the Rayyan software, whereas the Review Manager software was used to carry out the meta-analysis. A total of 16,605 articles were retrieved from the databases. After the duplicate removal, 2472 articles remained. These were eliminated using title screening, abstract screening, and full-length inspections. A total of nine articles were found eligible for quality assessment and meta-analysis, and the New Castle-Ottawa Scale was used for quality assessment. After the data extraction, 24 six articles were found to have the desired data format for the meta-analysis. RESULTS: The results showed significantly higher IFAR in the affected ears of individuals in the Meniere's disease group than in the control group's unaffected ears. There was no significant difference between the unaffected ears of individuals in the Meniere's disease group and the ears of the control group. The only study on Meniere's disease and benign paroxysmal positional vertigo found significantly larger ocular VEMP IFAR in ears with Meniere's disease than in benign paroxysmal positional vertigo. CONCLUSIONS: This systematic review and meta-analysis found IFAR efficient in differentiating Meniere's disease from healthy controls. We also found an enhanced IFAR as a potential marker for Meniere's disease. However, more investigations are needed to confirm the utility of an enhanced IFAR value in the exclusive identification of Meniere's disease.


Assuntos
Doença de Meniere , Potenciais Evocados Miogênicos Vestibulares , Vestíbulo do Labirinto , Humanos , Doença de Meniere/diagnóstico , Vertigem Posicional Paroxística Benigna/diagnóstico , Potenciais Evocados Miogênicos Vestibulares/fisiologia , Sáculo e Utrículo
12.
J Biomol Struct Dyn ; 41(9): 3752-3761, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35354393

RESUMO

Phycoerythrin (PE) is green light-absorbing pigment-protein that assists in efficient light harvesting in cyanobacteria and red-algae. PE in cyanobacteria stays less studied so far as compared to that in red algae. In this study, PE from marine cyanobacteria Halomicronema sp. R31DM is purified and subjected for its structural characterisation by X-ray crystallography in order to understand its light-harvesting characteristics. The crystal structure is solved to a resolution-limit of 2.21 Å with reasonable R-factors values, 0.16/0.21 (Rwork/ Rfree). PE forms hexamer of hetero-dimers made up of two peptide chains, α- and ß-subunits containing 2 and 3 phycoerythrobilin (PEB) chromophores covalently attached to them, respectively. Geometry of five chromophores is analysed along with their relative position within the PE hexamer. Also, their interactions with the surrounding microenvironment are analysed. The plausible energy transfer pathways in hexamer structure have been predicted based on relative position and geometry of chromophores. This structure enriches the structural information of cyanobacterial PE in order to understand its light-harvesting capacity.Communicated by Ramaswamy H. Sarma.


Assuntos
Cianobactérias , Ficoeritrina , Ficoeritrina/química , Ficoeritrina/metabolismo , Cianobactérias/química , Cianobactérias/metabolismo , Cristalografia por Raios X , Peptídeos/metabolismo
13.
Braz. J. Pharm. Sci. (Online) ; 59: e20200, 2023. graf
Artigo em Inglês | LILACS | ID: biblio-1505842

RESUMO

Abstract The renin-angiotensin-aldosterone system (RAAS) plays a key role in diabetic nephropathy (DN). Angiotensin-II secreted during the RAAS pathway increases nephropathy. It stimulates oxidative stress which can quench nitric oxide. Reduced nitric oxide level aggravates Ang-II-induced vasoconstriction. Ang-II has also emerged as a central mediator of the glomerular hemodynamic changes that are associated with renal injury. Deletion of ACE2 is also noted due to increased Ang-II level which leads to the development of DN. We hypothesize that nephropathy caused by Ang-II in the periphery may be controlled by brain RAAS. ACE inhibitors and ARBs may show the renoprotective effect when administered through ICV without crossing the blood-brain barrier. DN was observed after 8 weeks of diabetes induction through alloxan. Administration of captopril and valsartan once and in combined therapy for 2 weeks, significantly reduced urine output, blood urea nitrogen, total protein in the urine, serum cholesterol, serum creatinine, serum triglycerides, and kidney/body weight ratio as compared to diabetic control rats. Further, combination therapy significantly increased the body weight and serum nitrate level as compared to diabetic control animals. However, increased ACE2 levels in the brain may reduce the sympathetic outflow and might have decreased the peripheral activity of Ang-II which shows beneficial effects in DN.


Assuntos
Animais , Masculino , Feminino , Ratos , Sistema Renina-Angiotensina/imunologia , Angiotensina II/análise , Nefropatias Diabéticas/patologia , Ferimentos e Lesões/classificação , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Peptidil Dipeptidase A/administração & dosagem
14.
Sci Rep ; 12(1): 21115, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36477010

RESUMO

In this work, an analytical model is developed for DM-DG-TMD-FET- based Biosensor including Fringing-field effects. The Analytical model has been developed for two different Device structures, namely Device structure-1 (without a gate above the nano-cavity) and Device structure-2 (with a gate above the nano-cavity) based on modulation of the dielectric constant of biomolecules in the nano-cavity region. The proposed model has been validated against both numerical quantum simulation results with the help of a few fitting parameters and it also agrees with the 2-dimensional numeric simulator SILVACO TCAD used in this work. The presence/absence of biomolecules has been detected by the metric of threshold voltage sensitivity [Formula: see text] and drain current [Formula: see text] for the neutral as well as charged biomolecules. Sensitivities of partially filled nano-cavities arising out of steric hindrance in both the biosensors are compared. Optimization of device dimensions has also been included in this work to enhance the sensitivity of the biosensors. It has been witnessed that the sensitivity of the proposed biosensor is [Formula: see text] 100% higher in Device structure-1 for neutral biomolecules with dielectric constant [Formula: see text] = 12, when compared to Device structure-2 for fully filled cavities. Whereas for the charged biomolecules, Device structure-1 shows [Formula: see text] 50% enhanced sensitivity than Device structure-2 for [Formula: see text] [Formula: see text]. Device structure-1 demonstrates [Formula: see text]120% higher sensitivity than Device structure-2 with partially filled cavities (i.e. 66% filled cavity). Finally, benchmarking of the proposed biosensor is presented with contemporary, state-of-the-art biosensors and it is highlighted that [Formula: see text] FET-based biosensor emerges with a superior sensitivity of [Formula: see text] = 0.81 V for [Formula: see text].

15.
J Speech Lang Hear Res ; 65(11): 4454-4468, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36279585

RESUMO

PURPOSE: The aim of this study was to analyze the subcortical and cortical auditory evoked potentials for speech stimuli in children with speech-in-noise (SIN) deficits associated with auditory processing disorder (APD) without any reading or language deficits. METHOD: The study included 20 children in the age range of 9-13 years. Ten children were recruited to the APD group; they had below-normal scores on the speech-perception-in-noise test and were diagnosed as having APD. The remaining 10 were typically developing (TD) children and were recruited to the TD group. Speech-evoked subcortical (brainstem) and cortical (auditory late latency) responses were recorded and compared across both groups. RESULTS: The results showed a statistically significant reduction in the amplitudes of the subcortical potentials (both for stimulus in quiet and in noise) and the magnitudes of the spectral components (fundamental frequency and the second formant) in children with SIN deficits in the APD group compared to the TD group. In addition, the APD group displayed enhanced amplitudes of the cortical potentials compared to the TD group. CONCLUSION: Children with SIN deficits associated with APD exhibited impaired coding/processing of the auditory information at the level of the brainstem and the auditory cortex. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.21357735.


Assuntos
Transtornos da Percepção Auditiva , Percepção da Fala , Criança , Humanos , Adolescente , Transtornos da Percepção Auditiva/diagnóstico , Fala , Ruído , Percepção da Fala/fisiologia , Potenciais Evocados Auditivos , Estimulação Acústica , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia
16.
J Am Acad Audiol ; 33(3): 116-124, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-36216039

RESUMO

BACKGROUND: To achieve balance, persons with blindness (PWB) use proprioceptive and vestibular cues rather than the visual system; however, PWB are equally susceptible to acquire vestibular disorders. Reliable assessments of the vestibular system in PWB are essential to determine the presence or absence of vestibular disorders. PURPOSE: The saccular and the utricular functioning can be assessed using cervical vestibular-evoked myogenic potential and ocular vestibular-evoked myogenic potential, respectively. Evaluation of the functional integrity of the semicircular canals requires an assessment of the vestibular ocular reflex; however, this can be challenging in PWB. Video head impulse test (vHIT) assesses the vestibular ocular reflex (VOR) elicited against the natural high-frequency head movement in the planes of all six semicircular canals. This study aimed to explore the feasibility and outcomes of administering vHIT in PWB. RESEARCH DESIGN: Standard (static) groups comparison. STUDY SAMPLE: Nineteen young PWB and 23 age-matched adults with "normal" vision (control group) were included in the study. DATA COLLECTION AND ANALYSES: PWB underwent vHIT once, while the control group was tested in three conditions; condition 1 was used to simulate blindness for the control group, where vHIT was done in a pitch-dark room without prior instructions; condition 2 included vHIT testing in daylight, without a fixed visual target and any instructions; and condition 3 involved vHIT in daylight in the presence of a set visual target and with standard instructions to maintain visual focus on the visual target. RESULTS: The VOR gain was abnormal in the PWB group for all the canals. Among the PWB, the lateral canals (mean = 0.63) had the best VOR gain, followed by the anterior canals (mean = 0.53) and the posterior canals (mean = 0.31). In the control group, the VOR gain was significantly reduced in condition 1. There was no significant difference between the VOR gain in the PWB group and the control group in condition 1 for the lateral and the anterior canals. A higher proportion of participants in the PWB group had the presence of refixation saccades. CONCLUSION: VOR is significantly reduced in PWB but not completely absent. There may be a need to develop normative data for blind individuals to decide whether or not a person with blindness has a vestibular dysfunction, specifically a VOR deficit.


Assuntos
Teste do Impulso da Cabeça , Doenças Vestibulares , Adulto , Cegueira , Estudos de Viabilidade , Humanos , Reflexo Vestíbulo-Ocular/fisiologia , Canais Semicirculares , Doenças Vestibulares/diagnóstico
17.
3 Biotech ; 12(9): 224, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35975025

RESUMO

Phycobiliproteins (PBPs) of cyanobacteria and algae possess unique light harvesting capacity which expand the photosynthetically active region (PAR) and allow them to thrive in extreme niches where higher plants cannot. PBPs of cyanobacteria/algae vary in abundance, types, amino acid composition and in structure as a function of species and the habitat that they grow in. In the present review, the key aspects of structure, stability, and spectral properties of PBPs, and their correlation with ecological niche of cyanobacteria are discussed. Besides their role in light-harvesting, PBPs possess antioxidant, anti-aging, neuroprotective, hepatoprotective and anti-inflammatory properties, which can be used in therapeutics. Recent developments in therapeutic applications of PBPs are reviewed with special focus on 'route of PBPs administration' and 'therapeutic potential of PBP-derived peptide and chromophores'.

18.
Int. arch. otorhinolaryngol. (Impr.) ; 26(2): 281-288, Apr.-June 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1385098

RESUMO

Abstract Introduction Diabetes mellitus is a metabolic disease associated with a rise in the level of blood glucose. Individuals with diabetes mellitus are more likely to develop hearing loss, tinnitus, and dizziness due to macro- and microvascular complications. The extent to which auditory and vestibular functions are impaired in individuals with type-2 diabetes mellitus is still under debate. Objective To systematically review studies focusing on auditory and vestibular functions in individuals with type-2 diabetes mellitus. Data Synthesis A search was conducted in the PubMed, MedlinePlus, Ingenta Connect and Google Scholar databases for articles published until June 2019. A total of 15,980 articles were primarily retrieved, 33 of which were shortlisted based on the inclusion criteria set by the investigators for the systematic review. Out of 33 full-length articles, 26 evaluated the functioning of the auditory system, while 7 evaluated the functioning of the vestibular system. Most studies related to auditory functioning reported a significant effect of type-2 diabetes mellitus on the peripheral auditory system, whereas studies on vestibular functioning reported no significant effect of diabetes mellitus on the functioning of the peripheral vestibular end-organ. Conclusion Overall, the results of various audiological and peripheral vestibular tests reveal distinctive peripheral and/or central auditory and vestibular end-organ impairments in individuals with type-2 diabetes mellitus.

19.
Int Arch Otorhinolaryngol ; 26(2): e281-e288, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35602282

RESUMO

Introduction Diabetes mellitus is a metabolic disease associated with a rise in the level of blood glucose. Individuals with diabetes mellitus are more likely to develop hearing loss, tinnitus, and dizziness due to macro- and microvascular complications. The extent to which auditory and vestibular functions are impaired in individuals with type-2 diabetes mellitus is still under debate. Objective To systematically review studies focusing on auditory and vestibular functions in individuals with type-2 diabetes mellitus. Data Synthesis A search was conducted in the PubMed, MedlinePlus, Ingenta Connect and Google Scholar databases for articles published until June 2019. A total of 15,980 articles were primarily retrieved, 33 of which were shortlisted based on the inclusion criteria set by the investigators for the systematic review. Out of 33 full-length articles, 26 evaluated the functioning of the auditory system, while 7 evaluated the functioning of the vestibular system. Most studies related to auditory functioning reported a significant effect of type-2 diabetes mellitus on the peripheral auditory system, whereas studies on vestibular functioning reported no significant effect of diabetes mellitus on the functioning of the peripheral vestibular end-organ. Conclusion Overall, the results of various audiological and peripheral vestibular tests reveal distinctive peripheral and/or central auditory and vestibular end-organ impairments in individuals with type-2 diabetes mellitus.

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