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1.
Int J Audiol ; : 1-7, 2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36688600

RESUMEN

OBJECTIVE: To evaluate differences in tinnitus impact, hyperacusis and hearing threshold level (HTL) between patients with unilateral and bilateral tinnitus. For patients with unilateral tinnitus, to compare audiological variables for the tinnitus ear and the non-tinnitus ear. To assess whether the presence of unilateral tinnitus increases the likelihood of interaural hearing asymmetry (relative to bilateral tinnitus) that warrants referral for an MRI scan. DESIGN: Retrospective cross-sectional. STUDY SAMPLE: Data regarding HTLs and responses to self-report questionnaires were collected from the records of 311 patients attending a tinnitus clinic. RESULTS: 38.5% had unilateral tinnitus and the ears with tinnitus had higher HTLs and greater HTL slopes than the ears without tinnitus. There was no significant difference in tinnitus impact and hyperacusis between patients with unilateral and bilateral tinnitus. 40% of patients with unilateral tinnitus and 13% of patients with bilateral tinnitus had a between-ear difference in HTL ≥15 dB at two adjacent frequencies (2AF15 asymmetry). Unilateral tinnitus increased the risk of 2AF15 asymmetry by a factor of 4.4. CONCLUSIONS: Unilateral tinnitus increases the risk of having interaural asymmetry in HTLs that warrants referral for an MRI scan.

2.
J Virol ; 94(16)2020 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-32434889

RESUMEN

The continuing spread of HIV/AIDS is predominantly fueled by sexual exposure to HIV-contaminated semen. Seminal plasma (SP), the liquid portion of semen, harbors a variety of factors that may favor HIV transmission by facilitating viral entry into host cells, eliciting the production of proinflammatory cytokines, and enhancing the translocation of HIV across the genital epithelium. One important and abundant class of factors in SP is extracellular vesicles (EVs), which, in general, are important intercellular signal transducers. Although numerous studies have characterized blood plasma-derived EVs from both uninfected and HIV-infected individuals, little is known about the properties of EVs from the semen of HIV-infected individuals. We report here that fractionated SP enriched for EVs from HIV-infected men induces potent transcriptional responses in epithelial and stromal cells that interface with the luminal contents of the female reproductive tract. Semen EV fractions from acutely infected individuals induced a more proinflammatory signature than those from uninfected individuals. This was not associated with any observable differences in the surface phenotypes of the vesicles. However, microRNA (miRNA) expression profiling analysis revealed that EV fractions from infected individuals exhibit a broader and more diverse profile than those from uninfected individuals. Taken together, our data suggest that SP EVs from HIV-infected individuals exhibit unique miRNA signatures and exert potent proinflammatory transcriptional changes in cells of the female reproductive tract, which may facilitate HIV transmission.IMPORTANCE Seminal plasma (SP), the major vehicle for HIV, can modulate HIV transmission risk through a variety of mechanisms. Extracellular vesicles (EVs) are extremely abundant in semen, and because they play a key role in intercellular communication pathways and immune regulation, they may impact the likelihood of HIV transmission. However, little is known about the properties and signaling effects of SP-derived EVs in the context of HIV transmission. Here, we conduct a phenotypic, transcriptomic, and functional characterization of SP and SP-derived EVs from uninfected and HIV-infected men. We find that both SP and its associated EVs elicit potent proinflammatory transcriptional responses in cells that line the genital tract. EVs from HIV-infected men exhibit a more diverse repertoire of miRNAs than EVs from uninfected men. Our findings suggest that EVs from the semen of HIV-infected men may significantly impact the likelihood of HIV transmission through multiple mechanisms.


Asunto(s)
Vesículas Extracelulares/genética , MicroARNs/genética , Semen/metabolismo , Adulto , Estudios de Cohortes , Citocinas/metabolismo , Vesículas Extracelulares/metabolismo , Femenino , Genitales Femeninos , Infecciones por VIH/inmunología , VIH-1/fisiología , Humanos , Masculino , Conducta Sexual , Transcriptoma/genética
3.
J Virol ; 94(9)2020 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-32051267

RESUMEN

Clinical trials investigating histone deacetylase inhibitors (HDACi) to reverse HIV-1 latency aim to expose reservoirs in antiretroviral (ARV)-treated individuals to clearance by immune effectors, yet have not driven measurable reductions in the frequencies of infected cells. We therefore investigated the effects of the class I-selective HDACi nanatinostat and romidepsin on various blocks to latency reversal and elimination, including viral splicing, antigen presentation, and CD8+ T cell function. In ex vivo CD4+ T cells from ARV-suppressed individuals, both HDACi significantly induced viral transcription, but not splicing nor supernatant HIV-1 RNA. In an HIV-1 latency model using autologous CD8+ T cell clones as biosensors of antigen presentation, neither HDACi-treated CD4+ T cell condition induced clone degranulation. Both HDACi also impaired the function of primary CD8+ T cells in viral inhibition assays, with nanatinostat causing less impairment. These findings suggest that spliced or cell-free HIV-1 RNAs are more indicative of antigen expression than unspliced HIV-RNAs and may help to explain the limited abilities of HDACi to generate CD8+ T cell targets in vivoIMPORTANCE Antiretroviral (ARV) drug regimens suppress HIV-1 replication but are unable to cure infection. This leaves people living with HIV-1 burdened by a lifelong commitment to expensive daily medication. Furthermore, it has become clear that ARV therapy does not fully restore health, leaving individuals at elevated risk for cardiovascular disease, certain types of cancers, and neurocognitive disorders, as well as leaving them exposed to stigma. Efforts are therefore under way to develop therapies capable of curing infection. A key focus of these efforts has been on a class of drugs called histone deacetylase inhibitors (HDACi), which have the potential of exposing hidden reservoirs of HIV-1 to elimination by the immune system. Unfortunately, clinical trial results with HDACi have thus far been disappointing. In the current study, we integrate a number of experimental approaches to build a model that provides insights into the limited activity of HDACi in clinical trials and offers direction for future approaches.


Asunto(s)
Inhibidores de Histona Desacetilasas/farmacología , Latencia del Virus/efectos de los fármacos , Adulto , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Depsipéptidos/farmacología , Femenino , Infecciones por VIH/inmunología , Seropositividad para VIH/tratamiento farmacológico , VIH-1/metabolismo , VIH-1/patogenicidad , VIH-1/fisiología , Histona Desacetilasas/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Cultivo Primario de Células , Latencia del Virus/fisiología , Replicación Viral/efectos de los fármacos
4.
Ear Hear ; 42(4): 917-926, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33259445

RESUMEN

OBJECTIVES: The aim was to assess the internal consistency and convergent and discriminant validity of a new questionnaire for hyperacusis, the Inventory of Hyperacusis Symptoms (IHS; Greenberg & Carlos 2018), using a clinical population. DESIGN: This was a retrospective study. Data were gathered from the records of 100 consecutive patients who sought help for tinnitus and/or hyperacusis from an audiology clinic in the United Kingdom. The average age of the patients was 55 years (SD = 13 years). Audiological measures were the pure-tone average threshold (PTA) and uncomfortable loudness levels (ULL). Questionnaires administered were: IHS, Tinnitus Handicap Inventory (THI), Hyperacusis Questionnaire (HQ), Insomnia Severity Index, Generalized Anxiety Disorder, and Patient Health Questionnaire-9. RESULTS: Cronbach's alpha for the 25-item IHS questionnaire was 0.96. Neither the total IHS score nor scores for any of its five subscales were correlated with the PTA of the better or worse ear. This supports the discriminant validity of the IHS, as hyperacusis is thought to be independent of the PTA. There were moderately strong correlations between IHS total scores and scores for the HQ, Tinnitus Handicap Inventory, Generalized Anxiety Disorder, and Patient Health Questionnaire-9, with r = 0.58, 0.58, 0.61, 0.54, respectively. Thus, although IHS scores may reflect hyperacusis itself, they may also reflect the coexistence of tinnitus, anxiety, and depression. The total score on the IHS was significantly different between patients with and without hyperacusis (as diagnosed based on ULLs or HQ scores). Using the HQ score as a reference, the area under the receiver operating characteristic for the IHS was 0.80 (95% confidence interval = 0.71 to 0.89) and the cutoff point of the IHS with highest overall accuracy was 56/100. The corresponding sensitivity and specificity were 74% and 82%. CONCLUSIONS: The IHS has good internal consistency and reasonably high convergent validity, as indicated by the relationship of IHS scores to HQ scores and ULLs, but IHS scores may also partly reflect the co-occurrence of tinnitus, anxiety, and depression. We propose an IHS cutoff score of 56 instead of 69 for diagnosing hyperacusis.


Asunto(s)
Hiperacusia , Acúfeno , Ansiedad , Humanos , Hiperacusia/diagnóstico , Persona de Mediana Edad , Estudios Retrospectivos , Encuestas y Cuestionarios , Acúfeno/diagnóstico
5.
Transfusion ; 59(4): 1209-1222, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30835880

RESUMEN

BACKGROUND: Retrospective studies suggested that storage age of RBCs is associated with inflammation and thromboembolism. The Red Cell Storage Duration Study (RECESS) trial randomized subjects undergoing complex cardiac surgery to receive RBCs stored for shorter versus longer periods, and no difference was seen in the primary outcome of change in multiple organ dysfunction score. STUDY DESIGN AND METHODS: In the current study, 90 subjects from the RECESS trial were studied intensively using a range of hemostasis, immunologic, and nitric oxide parameters. Samples were collected before transfusion and on Days 2, 6, 28, and 180 after transfusion. RESULTS: Of 71 parameters tested, only 4 showed a significant difference after transfusion between study arms: CD8+ T-cell interferon-γ secretion and the concentration of extracellular vesicles bearing the B-cell marker CD19 were higher, and plasma endothelial growth factor levels were lower in recipients of fresh versus aged RBCs. Plasma interleukin-6 was higher at Day 2 and lower at Days 6 and 28 in recipients of fresh versus aged RBCs. Multiple parameters showed significant modulation after surgery and transfusion. Most analytes that changed after surgery did not differ based on transfusion status. Several extracellular vesicle markers, including two associated with platelets (CD41a and CD62P), decreased in transfused patients more than in those who underwent surgery without transfusion. CONCLUSIONS: Transfusion of fresh versus aged RBCs does not result in substantial changes in hemostasis, immune, or nitric oxide parameters. It is possible that transfusion modulates the level of platelet-derived extracellular vesicles, which will require study of patients randomly assigned to receipt of transfusion to define.


Asunto(s)
Antígenos CD , Coagulación Sanguínea/inmunología , Conservación de la Sangre , Transfusión de Eritrocitos , Eritrocitos/metabolismo , Interleucina-6 , Óxido Nítrico , Anciano , Antígenos CD/sangre , Antígenos CD/inmunología , Femenino , Humanos , Interleucina-6/sangre , Interleucina-6/inmunología , Masculino , Persona de Mediana Edad , Óxido Nítrico/sangre , Óxido Nítrico/inmunología , Estudios Retrospectivos , Factores de Tiempo
6.
Transfusion ; 59(4): 1223-1232, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30882927

RESUMEN

BACKGROUND: Several retrospective studies have suggested that transfusion with red blood cells (RBCs) stored for longer periods is associated with increased mortality. The Age of Blood Evaluation (ABLE) study randomized subjects to receive fresh vs. standard issue RBC units and showed no difference in the primary or secondary endpoints of mortality or change in multi-organ dysfunction syndrome (MODS) score. METHODS: In this study a subset of 100 ABLE subjects were enrolled to measure coagulation and immune parameters. Samples were collected pre-transfusion and on days 2, 6, 28, and 180 post-transfusion. Levels of 16 coagulation parameters, regulatory and functional T cells, 25 cytokines, and 16 markers of extracellular vesicles (EVs) were determined. RESULTS: Changes from baseline in levels of protein C, factor V, and EVs expressing phosphatidyl serine and CTLA-4 (CD152) differed between recipients of fresh and standard storage age RBC units, with the vast majority of coagulation and EV markers and all cytokines tested showing no difference between study arms. Although most analytes showed no difference between subjects in the fresh and standard arms of the study, 6 coagulation parameters, 15 cytokines, and 7 EV parameters changed significantly in the period post-transfusion. DISCUSSION: Transfusion of fresh vs. standard issue RBC units does not result in substantial changes in coagulation or immune parameters, up to day 35 of RBC storage. Furthermore, significant changes in multiple coagulation and immune parameters are detectable post-transfusion, though causality cannot be determined based on the current study.


Asunto(s)
Coagulación Sanguínea/inmunología , Conservación de la Sangre , Citocinas , Transfusión de Eritrocitos , Eritrocitos , Vesículas Extracelulares , Biomarcadores/sangre , Enfermedad Crítica , Citocinas/sangre , Citocinas/inmunología , Eritrocitos/inmunología , Eritrocitos/metabolismo , Vesículas Extracelulares/inmunología , Vesículas Extracelulares/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
7.
PLoS Pathog ; 12(6): e1005677, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27253379

RESUMEN

Identifying host immune determinants governing HIV transcription, latency and infectivity in vivo is critical to developing an HIV cure. Based on our recent finding that the host factor p21 regulates HIV transcription during antiretroviral therapy (ART), and published data demonstrating that the human carbohydrate-binding immunomodulatory protein galectin-9 regulates p21, we hypothesized that galectin-9 modulates HIV transcription. We report that the administration of a recombinant, stable form of galectin-9 (rGal-9) potently reverses HIV latency in vitro in the J-Lat HIV latency model. Furthermore, rGal-9 reverses HIV latency ex vivo in primary CD4+ T cells from HIV-infected, ART-suppressed individuals (p = 0.002), more potently than vorinostat (p = 0.02). rGal-9 co-administration with the latency reversal agent "JQ1", a bromodomain inhibitor, exhibits synergistic activity (p<0.05). rGal-9 signals through N-linked oligosaccharides and O-linked hexasaccharides on the T cell surface, modulating the gene expression levels of key transcription initiation, promoter proximal-pausing, and chromatin remodeling factors that regulate HIV latency. Beyond latent viral reactivation, rGal-9 induces robust expression of the host antiviral deaminase APOBEC3G in vitro and ex vivo (FDR<0.006) and significantly reduces infectivity of progeny virus, decreasing the probability that the HIV reservoir will be replenished when latency is reversed therapeutically. Lastly, endogenous levels of soluble galectin-9 in the plasma of 72 HIV-infected ART-suppressed individuals were associated with levels of HIV RNA in CD4+ T cells (p<0.02) and with the quantity and binding avidity of circulating anti-HIV antibodies (p<0.009), suggesting a role of galectin-9 in regulating HIV transcription and viral production in vivo during therapy. Our data suggest that galectin-9 and the host glycosylation machinery should be explored as foundations for novel HIV cure strategies.


Asunto(s)
Linfocitos T CD4-Positivos/virología , Galectinas/metabolismo , Infecciones por VIH/metabolismo , Activación Viral/fisiología , Latencia del Virus/fisiología , Fármacos Anti-VIH/uso terapéutico , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Perfilación de la Expresión Génica , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/fisiología , Humanos , Reacción en Cadena de la Polimerasa , Transcripción Genética/fisiología , Transcriptoma
8.
Int J Audiol ; 57(12): 941-946, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30272507

RESUMEN

OBJECTIVES: To explore the relationships between parental separation and parental mental health in childhood with tinnitus and hyperacusis disability in adulthood. DESIGN: Retrospective cross-sectional. STUDY SAMPLE: The data for consecutive patients who attended a tinnitus and hyperacusis clinic in the UK over a six months period were included (n = 184). RESULTS: 14.7% of patients reported that while they were growing up, their parents were separated or divorced. There were no significant differences in Tinnitus Handicap Inventory (THI) and Hyperacusis Questionnaire (HQ) between patients with and without history of parental separation. About 40.2% reported history of mental health disorders in their parents. The scores on THI and HQ were worse in the group that reported mental health disorders in their parents (p < .01). Parental mental health illness did not significantly relate to THI, however, it was significantly related to the risk of hyperacusis (odds ratio [OR], after adjusting for age and gender: 2.05, p = .026). The adjusted OR for a subgroup of patients with a diagnosis of hyperacusis was 6.7 (p = .011), indicating a stronger relationship for this subgroup. CONCLUSIONS: Among patients seeking help for their tinnitus and hyperacusis, poor parental mental health was associated with increased hyperacusis disability.


Asunto(s)
Divorcio/psicología , Hiperacusia/etiología , Salud Mental , Padres/psicología , Acúfeno/etiología , Factores de Edad , Umbral Auditivo , Estudios Transversales , Evaluación de la Discapacidad , Audición , Pruebas Auditivas , Humanos , Hiperacusia/diagnóstico , Hiperacusia/fisiopatología , Hiperacusia/psicología , Percepción Sonora , Estudios Retrospectivos , Factores de Riesgo , Encuestas y Cuestionarios , Acúfeno/diagnóstico , Acúfeno/fisiopatología , Acúfeno/psicología
9.
Noise Health ; 20(95): 162-170, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30136676

RESUMEN

BACKGROUND: Hyperacusis is intolerance of certain everyday sounds that causes significant distress and impairment in social, occupational, recreational, and other day-to-day activities. OBJECTIVE: The aim of this report is to summarize the key findings and conclusions from the Third International Conference on Hyperacusis. TOPICS COVERED: The main topics discussed comprise (1) diagnosis of hyperacusis and audiological evaluations, (2) neurobiological aspect of hyperacusis, (3) misophonia, (4) hyperacusis in autism spectrum disorder, (5) noise sensitivity, (6) hyperacusis-related distress and comorbid psychiatric illness, and (7) audiologist-delivered cognitive behavioral therapy for hyperacusis. CONCLUSIONS: Implications for research and clinical practice are summarised.


Asunto(s)
Hiperacusia/diagnóstico , Hiperacusia/terapia , Audiometría/métodos , Trastorno del Espectro Autista/complicaciones , Terapia Cognitivo-Conductual/métodos , Congresos como Asunto , Femenino , Humanos , Hiperacusia/etiología , Masculino
10.
Blood ; 123(5): 687-96, 2014 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-24335232

RESUMEN

Extracellular vesicles (EVs) are small, double membrane vesicles derived from leukocytes, platelets, and cells of other tissues under physiological or pathological conditions. Generation of EVs in stored blood is thought to be associated with adverse effects and potentially immunosuppression in blood transfusion recipients. We measured the quantity and cells of origin for EVs isolated from stored red blood cell (RBC) units and tested whether they had any effects on T-cell-mediated immune responses. Mixing peripheral blood mononuclear cells (PBMCs) with EVs resulted in secretion of proinflammatory cytokines and chemokines and increased survival of unstimulated PBMCs. EVs augmented mitogen-induced CD4(+) and CD8(+) T-cell proliferation in an antigen-presenting cell (APC)-dependent manner. We demonstrated that EVs interacted primarily with monocytes and induced proinflammatory cytokine secretion. We also showed that the exosome fraction of EVs and not larger microvesicles was responsible for induction of TNF-α production by monocytes. Furthermore, blockade of CD40 or CD40L accessory molecules largely neutralized the EV augmentation of T-cell responses, implying a role for cell-cell interaction between T cells and EV-activated monocytes. Contrary to our hypothesis, the data demonstrate that EVs isolated from RBC units increase the potency of APCs and boost mitogen-driven T-cell proliferative responses.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Citocinas/inmunología , Eritrocitos/inmunología , Exosomas/inmunología , Monocitos/inmunología , Conservación de la Sangre , Eritrocitos/citología , Humanos , Activación de Linfocitos
11.
Transfusion ; 56 Suppl 1: S52-64, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27001362

RESUMEN

BACKGROUND: Although a majority of the studies conducted to date on platelet (PLT) storage have been focused on PLT hemostatic function, the effects of 4°C PLTs on regulation of endothelial barrier permeability are still not known. In this study, we compared the effects of room temperature (22°C) stored and (4°C) stored PLTs on the regulation of vascular endothelial cell (EC) permeability in vitro and in vivo. STUDY DESIGN AND METHODS: Day 1, Day 5, and Day 7 leukoreduced apheresis PLTs stored at 4 or 22°C were studied in vitro and in vivo. In vitro, PLT effects on EC permeability and barrier function, adhesion, and impedance aggregometry were investigated. In vivo, using a mouse model of vascular leak, attenuation of vascular leak and circulating PLT numbers were measured. RESULTS: Treatment of EC monolayers with Day 5 or Day 7 PLTs, stored at both 22°C and 4°C, resulted in similar decreases in EC permeability on average. However, analysis of individual samples revealed significant variation that was donor dependent. Additional in vitro measurements revealed a decrease in inflammatory mediators, nonspecific PLT-endothelial aggregation and attenuated loss of aggregation over time to TRAP, ASPI, ADP, and collagen with 4°C storage. In mice, while 22°C and 4°C PLTs both demonstrated significant protection against vascular endothelial growth factor A (VEGF-A)-induced vascular leak 22°C PLTs exhibited increased protection compared to 4°C PLTs. Systemic circulating levels of 4°C PLTs were decreased compared to 22°C PLTs. CONCLUSIONS: In vitro, 4°C-stored PLTs exhibit a greater capacity to inhibit EC permeability than 22°C-stored PLTs. In vivo, 22°C PLTs provide superior control of vascular leak induced by VEGF-A. This discrepancy may be due to increased clearance of 4°C PLTs from the systemic circulation.


Asunto(s)
Plaquetas , Conservación de la Sangre , Permeabilidad Capilar , Frío , Endotelio Vascular/metabolismo , Calor , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Animales , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Factores de Tiempo
12.
Epilepsy Behav ; 60: 81-85, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27179714

RESUMEN

OBJECTIVE: Auditory temporal processing is the main feature of speech processing ability. Patients with temporal lobe epilepsy, despite their normal hearing sensitivity, may present speech recognition disorders. The present study was carried out to evaluate the auditory temporal processing in patients with unilateral TLE. MATERIALS AND METHODS: The present study was carried out on 25 patients with epilepsy: 11 patients with right temporal lobe epilepsy and 14 with left temporal lobe epilepsy with a mean age of 31.1years and 18 control participants with a mean age of 29.4years. The two experimental and control groups were evaluated via gap-in-noise and duration pattern sequence tests. One-way ANOVA was run to analyze the data. RESULTS: The mean of the threshold of the GIN test in the control group was observed to be better than that in participants with LTLE and RTLE. Also, it was observed that the percentage of correct responses on the DPS test in the control group and in participants with RTLE was better than that in participants with LTLE. CONCLUSION: Patients with TLE have difficulties in temporal processing. Difficulties are more significant in patients with LTLE, likely because the left temporal lobe is specialized for the processing of temporal information.


Asunto(s)
Percepción Auditiva , Epilepsia del Lóbulo Temporal/psicología , Adulto , Umbral Auditivo , Estudios Transversales , Electroencefalografía , Femenino , Lateralidad Funcional , Pruebas Auditivas , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad
13.
Int J Audiol ; 55(4): 239-47, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26795555

RESUMEN

Objective To determine the clinical utility of narrow-band chirp-evoked 40-Hz sinusoidal auditory steady state responses (s-ASSR) in the assessment of low-frequency hearing in noisy participants. Design Tone bursts and narrow-band chirps were used to respectively evoke auditory brainstem responses (tb-ABR) and 40-Hz s-ASSR thresholds with the Kalman-weighted filtering technique and were compared to behavioral thresholds at 500, 2000, and 4000 Hz. A repeated measure ANOVA and post-hoc t-tests, and simple regression analyses were performed for each of the three stimulus frequencies. Study sample Thirty young adults aged 18-25 with normal hearing participated in this study. Results When 4000 equivalent response averages were used, the range of mean s-ASSR thresholds from 500, 2000, and 4000 Hz were 17-22 dB lower (better) than when 2000 averages were used. The range of mean tb-ABR thresholds were lower by 11-15 dB for 2000 and 4000 Hz when twice as many equivalent response averages were used, while mean tb-ABR thresholds for 500 Hz were indistinguishable regardless of additional response averaging. Conclusion Narrow-band chirp-evoked 40-Hz s-ASSR requires a ∼15 dB smaller correction factor than tb-ABR for estimating low-frequency auditory threshold in noisy participants when adequate response averaging is used.


Asunto(s)
Estimulación Acústica/métodos , Umbral Auditivo , Potenciales Evocados Auditivos del Tronco Encefálico , Percepción de la Altura Tonal , Adolescente , Adulto , Audiometría de Tonos Puros , Señales (Psicología) , Electroencefalografía , Femenino , Humanos , Masculino , Ruido/efectos adversos , Patrones de Reconocimiento Fisiológico , Enmascaramiento Perceptual , Valor Predictivo de las Pruebas , Adulto Joven
14.
Cytometry A ; 87(11): 1052-63, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25847910

RESUMEN

Extracellular vesicles (EVs) range in size from 50 nm to 1 µm. Flow cytometry (FCM) is the most commonly used method for analyzing EVs; however, accurate characterization of EVs remains challenging due to their small size and lack of discrete positive populations. Here we report the use of optimization techniques that are especially well-suited for analyzing EVs from a high volume of clinical samples. Utilizing a two pronged approach that included 1) pre-filtration of antibodies to remove aggregates, followed by 2) detergent lysis of a replicate sample to account for remaining false positive events, we were able to effectively limit false positive non-EV events. In addition, we show that lysed samples are a useful alternative to isotypes for setting gates to exclude background fluorescence. To reduce background, we developed an approach using filters to "wash" samples post-staining thus providing a faster alternative to ultracentrifugation and sucrose gradient fractionation. In conclusion, use of these optimized techniques enhances the accuracy and efficiency of EV detection using FCM.


Asunto(s)
Vesículas Extracelulares , Citometría de Flujo , Anticuerpos/inmunología , Antígenos CD/inmunología , Filtración/métodos , Citometría de Flujo/métodos , Humanos , Coloración y Etiquetado/métodos
15.
Retrovirology ; 11: 57, 2014 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-24996903

RESUMEN

BACKGROUND: CD4+ T cells are critically important in HIV infection, being both the primary cells infected by HIV and likely playing a direct or indirect role in helping control virus replication. Key areas of interest in HIV vaccine research are mechanisms of viral escape from the immune response. Interestingly, in HIV infection it has been shown that peptide sequence variation can reduce CD4+ T cell responses to the virus, and small changes to peptide sequences can transform agonist peptides into antagonist peptides. RESULTS: We describe, at a molecular level, the consequences of antagonism of HIV p24-specific CD4+ T cells. Antagonist peptide exposure in the presence of agonist peptide caused a global suppression of agonist-induced gene expression and signaling molecule phosphorylation. In addition to down-regulation of factors associated with T cell activation, a smaller subset of genes associated with negative regulation of cell activation was up-regulated, including KFL-2, SOCS-1, and SPDEY9P. Finally, antagonist peptide in the absence of agonist peptide also delivered a negative signal to T cells. CONCLUSIONS: Small changes in p24-specific peptides can result in T cell antagonism and reductions of both T cell receptor signaling and activation. These changes are at least in part mediated by a dominant negative signal delivered by antagonist peptide, as evidenced by up-regulation of negative regulatory genes in the presence of agonist plus antagonist stimulation. Antagonism can have dramatic effects on CD4+ T cell function and presents a potential obstacle to HIV vaccine development.


Asunto(s)
Linfocitos T CD4-Positivos/efectos de los fármacos , Epítopos de Linfocito T , Proteína p24 del Núcleo del VIH/inmunología , VIH/inmunología , Activación de Linfocitos , Péptidos/farmacología , Linfocitos T/inmunología , Secuencia de Aminoácidos , Animales , Linfocitos T CD4-Positivos/inmunología , Citocinas/biosíntesis , Macaca mulatta , Datos de Secuencia Molecular , Análisis de Secuencia por Matrices de Oligonucleótidos , Fosforilación , Factores de Transcripción STAT/fisiología , Transducción de Señal
16.
J Clin Med ; 13(11)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38892775

RESUMEN

Background: Vestibular schwannoma (VS) is a benign tumor of the eighth cranial nerve formed from neoplastic Schwann cells. Although VS can cause a variety of symptoms, tinnitus is one of the most distressing symptoms for patients and can greatly impact quality of life. The objective of this systematic review is to comprehensively examine and compare the outcomes related to tinnitus in patients undergoing treatment for VS. Specifically, it evaluates patient experiences with tinnitus following the removal of VS using the various surgical approaches of traditional surgical resection and gamma knife radiosurgery (GKS). By delving into various aspects such as the severity of tinnitus post-treatment, the duration of symptom relief, patient quality of life, new onset of tinnitus after VS treatment, and any potential complications or side effects, this review aims to provide a detailed analysis of VS treatment on tinnitus outcomes. Methods: Following PRISMA guidelines, articles were included from PubMed, Science Direct, Scopus, and EMBASE. Quality assessment and risk of bias analysis were performed using a ROBINS-I tool. Results: Although VS-associated tinnitus is variable in its intensity and persistence post-resection, there was a trend towards a decreased tinnitus burden in patients. Irrespective of the surgical approach or the treatment with GKS, there were cases of persistent or worsened tinnitus within the studied cohorts. Conclusion: The findings of this systematic review highlight the complex relationship between VS resection and tinnitus outcomes. These findings underscore the need for individualized patient counseling and tailored treatment approaches in managing VS-associated tinnitus. The findings of this systematic review may help in guiding clinicians towards making more informed and personalized healthcare decisions. Further studies must be completed to fill gaps in the current literature.

17.
medRxiv ; 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38496497

RESUMEN

Background: The primary barrier to curing HIV infection is the pool of intact HIV proviruses integrated into host cell DNA throughout the bodies of people living with HIV (PLHIV), called the HIV reservoir. Reservoir size is impacted by the duration of HIV infection, delay in starting antiretroviral therapy (ART), and breakthrough viremia during ART. The leading infectious cause of death worldwide for PLHIV is TB, but we don't know how TB impacts the HIV reservoir. Methods: We designed a case-control study to compare HIV provirus-containing CD4 in PLHIV with vs. without a history of active TB disease. Study participants in the pilot and confirmatory cohort were enrolled at GHESKIO Centers in Port au Prince, Haiti. Intact and non-intact proviral DNA were quantified using droplet digital PCR of PBMC-derived CD4 cells. For a subset, Th1 and Th2 cytokines were assayed in plasma. Kruskal-Wallis tests were used to compare medians with tobit regression for censoring. Results: In the pilot cohort, we found that PLHIV with history of active pulmonary TB (n=20) had higher intact provirus than PLHIV without history of active TB (n=47) (794 vs 117 copies per million CD4, respectively; p<0.0001). In the confirmatory cohort, the quantity of intact provirus was higher in the TB group (n=13) compared with the non-TB group (n=18) (median 102 vs. 0 intact provirus per million CD4, respectively p=0.03). Additionally, we found that the frequencies of CD4+ T cells with any detectable proviral fragment was directly proportional to the levels of IL1B (p= 0.0025) and IL2 (p=0.0002). Conclusions: This is the first assessment of HIV provirus using IPDA in a clinical cohort from a resource limited setting, and the finding of larger reservoir in PLHIV with history of TB has significant implications for our understanding of TB-HIV coinfection and HIV cure efforts in TB-endemic settings.

18.
J Am Acad Audiol ; 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37146649

RESUMEN

BACKGROUND: In the UK, audiologist-delivered cognitive behavioral therapy (CBT) is a key intervention to alleviate the distress caused by tinnitus and its comorbid hyperacusis. However, the availability of face-to-face CBT is limited, and such therapy involves significant costs. CBT provided via the internet provides a potential solution to improve access to CBT for tinnitus. PURPOSE: The aim was to perform a preliminary assessment of the effect of a specific program of non-guided internet-based CBT for tinnitus, denoted iCBT(T), in alleviating the problems caused by tinnitus alone or tinnitus combined with hyperacusis. RESEARCH DESIGN: This was a retrospective cross-sectional study. STUDY SAMPLE: The data for 28 people with tinnitus who completed the iCBT(T) program and answered a series of questions about their tinnitus and hearing status were included in the study. Twelve patients reported also having hyperacusis (including five also with misophonia). DATA COLLECTION AND ANALYSIS: The iCBT(T) program has seven self-help modules. Anonymous data were collected retrospectively from patients' answers to the questions in the iCBT(T) initial and final assessment modules. Questionnaires administered within the iCBT(T) program were: 4C Tinnitus Management Questionnaire (4C), Screening for Anxiety and Depression in Tinnitus (SAD-T), and the CBT Effectiveness Questionnaire (CBT-EQ). RESULTS: Responses to the 4C showed a significant improvement from pre- to post-treatment, with a medium effect size. The mean improvement was similar for those with and without hyperacusis. Responses to the SAD-T questionnaire also showed a significant improvement from pre- to post-treatment with a medium effect size. The improvement was significantly greater for participants with tinnitus alone than for participants who also had hyperacusis. For both the 4C and the SAD-T, the improvements were not significantly related to age or gender. Participants' views of the effectiveness of the iCBT(T) program were assessed using the CBT-EQ. The mean score was 50 out of a maximum of 80, indicating moderately high effectiveness. CBT-EQ scores did not differ for those with and without hyperacusis. CONCLUSIONS: Based on this preliminary analysis, the iCBT(T) program showed promising result in improving the ability to manage tinnitus and decreasing symptoms of anxiety and depression. Future studies with larger samples and control group(s) are required to further assess various aspects of this program.

19.
J Biol Chem ; 286(41): 35650-35662, 2011 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-21849511

RESUMEN

Group V-secreted phospholipase A(2) (GV sPLA(2)) hydrolyzes bacterial phospholipids and initiates eicosanoid biosynthesis. Here, we elucidate the role of GV sPLA(2) in the pathophysiology of Escherichia coli pneumonia. Inflammatory cells and bronchial epithelial cells both express GV sPLA(2) after pulmonary E. coli infection. GV(-/-) mice accumulate fewer polymorphonuclear leukocytes in alveoli, have higher levels of E. coli in bronchoalveolar lavage fluid and lung, and develop respiratory acidosis, more severe hypothermia, and higher IL-6, IL-10, and TNF-α levels than GV(+/+) mice after pulmonary E. coli infection. Eicosanoid levels in bronchoalveolar lavage are similar in GV(+/+) and GV(-/-) mice after lung E. coli infection. In contrast, GV(+/+) mice have higher levels of prostaglandin D(2) (PGD(2)), PGF(2α), and 15-keto-PGE(2) in lung and express higher levels of ICAM-1 and PECAM-1 on pulmonary endothelial cells than GV(-/-) mice after lung infection with E. coli. Selective deletion of GV sPLA(2) in non-myeloid cells impairs leukocyte accumulation after pulmonary E. coli infection, and lack of GV sPLA(2) in either bone marrow-derived myeloid cells or non-myeloid cells attenuates E. coli clearance from the alveolar space and the lung parenchyma. These observations show that GV sPLA(2) in bone marrow-derived myeloid cells as well as non-myeloid cells, which are likely bronchial epithelial cells, participate in the regulation of the innate immune response to pulmonary infection with E. coli.


Asunto(s)
Células de la Médula Ósea/inmunología , Bronquios/inmunología , Células Epiteliales/inmunología , Infecciones por Escherichia coli/inmunología , Escherichia coli/inmunología , Fosfolipasas A2 Grupo V/inmunología , Inmunidad Innata , Células Mieloides/inmunología , Neumonía Bacteriana/inmunología , Animales , Células de la Médula Ósea/enzimología , Células de la Médula Ósea/patología , Bronquios/enzimología , Bronquios/patología , Lavado Broncoalveolar , Citocinas/genética , Citocinas/inmunología , Citocinas/metabolismo , Células Epiteliales/enzimología , Células Epiteliales/patología , Escherichia coli/metabolismo , Infecciones por Escherichia coli/enzimología , Infecciones por Escherichia coli/genética , Infecciones por Escherichia coli/patología , Fosfolipasas A2 Grupo V/genética , Fosfolipasas A2 Grupo V/metabolismo , Hidrólisis , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/inmunología , Molécula 1 de Adhesión Intercelular/metabolismo , Ratones , Ratones Noqueados , Células Mieloides/enzimología , Células Mieloides/patología , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/genética , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/inmunología , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Neumonía Bacteriana/enzimología , Neumonía Bacteriana/genética , Neumonía Bacteriana/patología , Prostaglandina D2/genética , Prostaglandina D2/inmunología , Prostaglandina D2/metabolismo , Alveolos Pulmonares/enzimología , Alveolos Pulmonares/inmunología , Alveolos Pulmonares/patología
20.
Cytokine ; 59(2): 433-41, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22652417

RESUMEN

CXCL10 is part of the group of interferon-stimulated genes and it plays an important role during different viral infections by inducing cell activation, chemotaxis and lymphocyte priming toward the Th1 phenotype. In this study, we investigated in vitro the effects of CXCL10 in activated human primary T lymphocytes in terms of apoptosis or survival, and delineated the signaling pathways that are involved. CXCL10, in combination with IL-2 and/or IFNα, induces apoptosis in T lymphocytes. Moreover, CXCL10-induced activation of CXCR3 also triggers pro-survival signals that can be blocked by pertussis toxin. The analysis of the downstream signaling kinases shows that apoptosis is p38 MAPK-dependent and the pro-survival signals rely on the sustained activation of PI3K and the transient activation of Akt. On the other hand, the transient activation of p44/p42 ERK did not have an impact on T lymphocyte survival. We propose an immunological model in which CXCL10, together with other co-stimulating cytokines, participates in the activation of T lymphocytes, promotes survival and expansion of certain lymphocyte subsets, and induces chemotaxis toward the infected tissues. On the other hand, CXCL10 might contribute to the triggering of apoptosis in other subsets of T lymphocytes, including those lymphocytes that were transiently activated but later lacked the appropriate sets of specific co-stimulating signals to ensure their survival.


Asunto(s)
Apoptosis , Quimiocina CXCL10/metabolismo , Linfocitos T/citología , Linfocitos T/enzimología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Adulto , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Activación Enzimática/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Interferón-alfa/farmacología , Interleucina-2/farmacología , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores CXCR3/metabolismo , Proteínas Recombinantes/farmacología , Transducción de Señal/efectos de los fármacos , Linfocitos T/efectos de los fármacos , Adulto Joven
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