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1.
Otolaryngol Clin North Am ; 56(2): 215-231, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37030936

RESUMO

Diagnosis of larynx cancer relies on a detailed history and physical and objective assessment with endoscopy and imaging. Endoscopy is needed to assess for vocal fold function that directly affects staging. Computed tomography and MRI can be used to assess for tumor extent in relation to intra- and extra-laryngeal structures, especially paraglottic and pre-epiglottic space involvement as well as cartilage invasion. Accurate staging is critical for subsequent treatment decision-making regarding larynx preservation.


Assuntos
Neoplasias Laríngeas , Laringe , Humanos , Neoplasias Laríngeas/diagnóstico por imagem , Neoplasias Laríngeas/patologia , Estadiamento de Neoplasias , Laringe/diagnóstico por imagem , Laringe/patologia , Tomografia Computadorizada por Raios X , Prega Vocal/patologia
2.
JAMA Otolaryngol Head Neck Surg ; 149(6): 485-492, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37079310

RESUMO

Importance: The management of vestibular schwannoma may include observation, microsurgical resection, or radiation of a tumor near the facial nerve. Injury to the facial nerve can result in facial paralysis with major functional, social, and psychological sequelae, and the experiences of patients after paralysis are not well studied. Objective: To (1) identify patient preparedness for developing facial paralysis and how well their care is coordinated following its development and (2) present in their own words outcomes of facial paralysis in terms of physical health, emotional health, self-perception, and social interactions. Design, Setting, and Participants: A qualitative observational study was performed using semistructured interviews at a tertiary care academic medical center. Semistructured interviews were conducted between January 1, 2018, and June 30, 2019, with adults aged 25 to 70 years who developed facial paralysis after treatment for vestibular schwannoma. Data were analyzed from July 2019 to June 2020. Main Outcomes and Measures: Perceptions of the educational and emotional experiences of individuals who developed complete facial paralysis after surgical treatment of vestibular schwannoma. Results: Overall, 12 participants were interviewed (median age, 54 years [range, 25-70 years]; 11 were female). Saturation was achieved after 12 interviews, indicating that no further information could be elicited from additional interviews. Four major themes were identified: (1) lack of sufficient patient education about the diagnosis of facial paralysis; (2) lack of appropriate care coordination related to facial paralysis; (3) changes in physical and emotional health following facial paralysis; and (4) changes in social interactions and external support following facial paralysis. Conclusions and Relevance: It is well-known that patients with facial paralysis have reduced quality of life, severe psychological and emotional sequelae. However, little is currently done to help prepare patients for this undesirable outcome. In this qualitative study of facial paralysis, patients express, in their own words, their feeling that the education and management of facial paralysis by their clinicians was inadequate. Before patients undergo surgery, and certainly after injury to the facial nerve, clinicians should consider the patient's goals, preferences, and values to ensure that a comprehensive educational program and psychosocial support system are implemented. Facial reanimation research has not adequately captured these key patient factors associated with the quality of communication.


Assuntos
Paralisia Facial , Neuroma Acústico , Angústia Psicológica , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Paralisia Facial/psicologia , Neuroma Acústico/cirurgia , Qualidade de Vida/psicologia , Percepção
3.
Otolaryngol Head Neck Surg ; 169(2): 333-339, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36939596

RESUMO

OBJECTIVE: This study aims to investigate patterns of cochlear ossification (CO) in cadaveric temporal bones of patients who underwent vestibular schwannoma (VS) surgery via the translabyrinthine (TL), middle cranial fossa (MF), or retrosigmoid (RS) approaches. STUDY DESIGN: Histopathologic analysis of cadaveric temporal bones. SETTING: Multi-institutional national temporal bone repository. METHODS: The National Institute of Deafness and Communication Disorders and House Temporal Bone Laboratory at the University of California, Los Angeles and the Massachusetts Eye and Ear Otopathology Laboratory were searched for cadaveric temporal bones with a history of VS for which microsurgery was performed. Exclusion criteria included non-VS and perioperative death within 30 days of surgery. Temporal bones were analyzed histologically for CO of the basal, middle, and apical turns. RESULTS: Of 92 temporal bones with a history of schwannoma from both databases, 12 of these cases met the inclusion criteria. The approaches for tumor excision included 2 MF, 4 RS, and 6 TL approaches. CO was observed in all temporal bones that had undergone TL surgery. Among temporal bones that had undergone MF or RS surgeries, 5/6 had no CO, and 1/6 had partial ossification. This single case was noted to have intraoperative vestibular violation after RS surgery upon histopathologic and chart review. CONCLUSION: In this temporal bone series, all temporal bones that had undergone TL demonstrated varying degrees of CO on histological analysis. MF and RS cases did not exhibit CO except in the case of vestibular violation. When cochlear implantation is planned or possible after VS surgery, surgeons may consider using a surgical approach that does not violate the labyrinth.


Assuntos
Implante Coclear , Neuroma Acústico , Vestíbulo do Labirinto , Humanos , Cadáver , Neuroma Acústico/cirurgia , Neuroma Acústico/patologia , Osteogênese , Estudos Retrospectivos , Osso Temporal/cirurgia
5.
Infect Dis Clin Microbiol ; 5(3): 251-256, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38633560

RESUMO

A retropharyngeal abscess (RPA) in early childhood is not uncommon due to at-risk lymph nodes in this deep neck space and is typified by fever, odynophagia, and a constellation of respiratory manifestations. However, RPA is exceedingly rare in the neonatal subpopulation and not part of the usual differential diagnosis algorithm in this age range. Herein, we present a unique case of a previously healthy 5-week-old male infant with protracted "congestion" and difficulty in oral feeding, whose clinical course is confounded by intermittent, positional bradycardia and subsequent apnea. He was eventually diagnosed with a methicillin-resistant Staphylococcus aureus (MRSA) RPA, leading to concurrent vascular and airways compromise in the form of baroreceptor-mediated bradycardia from mass-effect carotid body compression. This clinical case is an important reminder that any infant with positional vital sign changes should prompt urgent and thorough investigation for extraordinary and otherwise uncommon pathophysiologic states. The case also highlights the power of multidisciplinary collaboration across multiple specialties and parental advocacy in unifying a diagnosis for rare pediatric illnesses.

7.
Cureus ; 14(6): e26336, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35911292

RESUMO

We present a unique case of mandibular reconstruction using virtual surgical planning (VSP) of a post-traumatic mandibular non-union defect for a patient with familial dysautonomia (FD), also known as Riley-Day Syndrome. In this case, the complexity related to perioperative and surgical challenges illustrates the utility of VSP and the importance of multi-disciplinary collaboration in jaw-free flap reconstructive surgery. We highlight our experience with the "Jaw-In-A-Day" approach in conjunction with tailored preoperative planning and perioperative care resulting in successful mandibular free flap reconstruction.

8.
Adv Exp Med Biol ; 1327: 169-189, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34279838

RESUMO

With the largest viral loads in both symptomatic and asymptomatic patients with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) present in the oral and nasal cavities, agents that act on these two areas have the potential for large therapeutic and prophylactic benefit. A literature review was conducted to elucidate the possible agents useful in treatment of SARS-CoV-2. These agents were evaluated for their current applications, adverse reactions, their current state of study, and any future considerations in their management of coronavirus disease 2019 (COVID-2019). Our review has found that, while there are many promising agents with proven efficacy in their in-vitro efficacy against SARS-CoV-2, more clinical trials and in-vivo studies, as well as safety trials, must be conducted before these agents can be effectively implemented.


Assuntos
COVID-19 , Antivirais/uso terapêutico , Humanos , SARS-CoV-2 , Carga Viral
9.
JMIR Public Health Surveill ; 7(1): e24220, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33406478

RESUMO

BACKGROUND: Real-time polymerase chain reaction using nasopharyngeal swabs is currently the most widely used diagnostic test for SARS-CoV-2 detection. However, false negatives and the sensitivity of this mode of testing have posed challenges in the accurate estimation of the prevalence of SARS-CoV-2 infection rates. OBJECTIVE: The purpose of this study was to evaluate whether technical and, therefore, correctable errors were being made with regard to nasopharyngeal swab procedures. METHODS: We searched a web-based video database (YouTube) for videos demonstrating SARS-CoV-2 nasopharyngeal swab tests, posted from January 1 to May 15, 2020. Videos were rated by 3 blinded rhinologists for accuracy of swab angle and depth. The overall score for swab angle and swab depth for each nasopharyngeal swab demonstration video was determined based on the majority score with agreement between at least 2 of the 3 reviewers. We then comparatively evaluated video data collected from YouTube videos demonstrating the correct nasopharyngeal swab technique with data from videos demonstrating an incorrect nasopharyngeal swab technique. Multiple linear regression analysis with statistical significance set at P=.05 was performed to determine video data variables associated with the correct nasopharyngeal swab technique. RESULTS: In all, 126 videos met the study inclusion and exclusion criteria. Of these, 52.3% (66/126) of all videos demonstrated the correct swab angle, and 46% (58/126) of the videos demonstrated an appropriate swab depth. Moreover, 45.2% (57/126) of the videos demonstrated both correct nasopharyngeal swab angle and appropriate depth, whereas 46.8% (59/126) of the videos demonstrated both incorrect nasopharyngeal swab angle and inappropriate depth. Videos with correct nasopharyngeal swab technique were associated with the swab operators identifying themselves as a medical professional or as an Ear, Nose, Throat-related medical professional. We also found an association between correct nasopharyngeal swab techniques and recency of video publication date (relative to May 15, 2020). CONCLUSIONS: Our findings show that over half of the videos documenting the nasopharyngeal swab test showed an incorrect technique, which could elevate false-negative test rates. Therefore, greater attention needs to be provided toward educating frontline health care workers who routinely perform nasopharyngeal swab procedures.


Assuntos
Teste para COVID-19/métodos , Nasofaringe/virologia , SARS-CoV-2/isolamento & purificação , Mídias Sociais , Manejo de Espécimes/métodos , Gravação em Vídeo , Erros de Diagnóstico/prevenção & controle , Humanos , Reação em Cadeia da Polimerase em Tempo Real
10.
Ann Otol Rhinol Laryngol ; 130(7): 810-817, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33251849

RESUMO

OBJECTIVE: To compare the patient experience of a virtual otolaryngology clinic visit to an in-person visit, especially with its significantly increased implementation during the COVID-19 pandemic. METHODS: Patient satisfaction (PS) metrics from the Clinician and Group Consumer Assessment of Healthcare Providers and Systems survey were queried from March 1, 2020 to May 1, 2020 for telehealth visits and January 1, 2020 to March 1, 2020 for in-person visits. Overlapping and comparable questions were analyzed using Mann-Whitney U test, Chi-square test for independence, and Student's t-test. RESULTS: There were 1284 partial or complete PS surveys from in-person visits and 221 partial or complete virtual PS surveys. There were statistically significantly worse virtual visit evaluations of provider listening, conveyance of information, likelihood to recommend, and overall provider ratings compared to in-person visits. CONCLUSION: Telehealth has become the new norm for most healthcare providers in the United States. This study demonstrates some of the initial shortcomings of telehealth in an otolaryngology practice and identifies challenges with interpersonal communication that may need to be addressed as telehealth becomes increasingly prevalent. LEVEL OF EVIDENCE: 3.


Assuntos
COVID-19/epidemiologia , Otolaringologia/organização & administração , Pandemias , Satisfação do Paciente , Consulta Remota , Assistência Ambulatorial , California/epidemiologia , Comunicação , Pesquisas sobre Atenção à Saúde , Humanos , Relações Médico-Paciente , SARS-CoV-2
11.
OTO Open ; 4(2): 2473974X20933573, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32551407

RESUMO

This study evaluates the patient experience during virtual otolaryngology clinic visits implemented during the coronavirus disease 2019 (COVID-19) pandemic. Patient satisfaction surveys were queried from January 1, 2020, to May 1, 2020, for both telehealth and in-person visits. A descriptive analysis of the question responses was performed. There were 195 virtual and 4013 in-person visits with surveys completed in this time period. Ratings related to provider-patient communication were poor for virtual visits. Telehealth has become the new norm for most health care providers in the United States. This study demonstrates some of the initial shortcomings of telehealth in an otolaryngology practice and identifies challenges with interpersonal communication that may need to be addressed as telehealth becomes increasingly prevalent.

12.
Am J Rhinol Allergy ; 34(4): 494-501, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32168997

RESUMO

BACKGROUND: The urban homeless population has increased exposure to risk factors associated with chronic rhinosinusitis (CRS). However, a gap in knowledge of the prevalence of sinonasal symptoms in these demographic limits complete understanding of CRS epidemiology. There is a need to elucidate sinonasal disease burden in this vulnerable patient population to bring awareness to any existing disparities. OBJECTIVE: To assess the prevalence, severity, and associated factors of CRS clinical symptoms and health-care barriers in an urban homeless population. METHODS: Homeless adults completed a sociodemographic questionnaire and the 22-item Sinonasal Outcome Test (SNOT-22) and EuroQol-5 Dimension-3 Level-Visual Analog Scale surveys. Responses were categorized by potential CRS symptoms defined as reporting at least 2 CRS cardinal symptoms. Risk factors associated with potential CRS symptoms were analyzed with multivariate regression models. RESULTS: Fifty-six (16%) out of 341 total subjects reported potential CRS symptoms. Those with potential CRS symptoms had a higher median SNOT-22 score (53 vs 22, P < .001) than those without. Logistic regression models identified history of smoking (odds ratio [OR], 6.54; 95% confidence interval [CI], 2.04-21.04) and duration of homelessness over 3 months (OR, 3.46; CI, 1.51-7.94) as factors associated with potential CRS symptoms. Duration of homelessness over 3 months was associated with higher SNOT-22 scores (standardized beta coefficient [ß], 0.48; CI, 0.39-0.57). Among those reporting 2 or more CRS cardinal symptoms, 18% had ever been seen by any physician for their symptoms. CONCLUSIONS: Our study estimates a high prevalence of potential CRS symptoms in the urban homeless population. Longer duration of homelessness was associated with potential CRS symptoms and poor CRS-specific quality of life scores. Disparities in access to care emphasize the need for increased preventive efforts designed for this unique patient group.


Assuntos
Pessoas Mal Alojadas , Seios Paranasais/patologia , Rinite/epidemiologia , Sinusite/epidemiologia , População Urbana , Adulto , Doença Crônica , Progressão da Doença , Feminino , Acessibilidade aos Serviços de Saúde , Disparidades em Assistência à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Saúde Pública , Qualidade de Vida , Rinite/fisiopatologia , Teste de Desfecho Sinonasal , Sinusite/fisiopatologia , Estados Unidos/epidemiologia
14.
Laryngoscope ; 130(11): E587-E592, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31756005

RESUMO

OBJECTIVES/HYPOTHESIS: To determine differences in time course of care based on major insurance types for patients with head and neck squamous cell carcinoma (HNSCC). STUDY DESIGN: Retrospective cohort study. METHODS: Retrospective study of Health Maintenance Organization (HMO), Preferred Provider Organization (PPO), and Medicare patients with biopsy-proven diagnosis of HNSCC referred to an academic tertiary center for tumor resection and adjuvant therapy. In addition to patient demographic information and tumor characteristics, duration of chief complaint and the following time points were collected: biopsy by referring physician, first specialty surgeon clinic appointment, surgery, and adjuvant radiation start and stop dates. RESULTS: There was a statistically significant increase in time interval for HMO (n = 32) patients from chief complaint to biopsy (P = .003), biopsy to first specialty surgeon clinic appointment (P < .001), and surgery to start of adjuvant radiation (P < .001) compared to that of Medicare (n = 31) and PPO (n = 41) patients. Adjuvant radiation was initiated ≤6 weeks after surgery in 22% of HMO (mean duration of 59 ± 17 days), 48% of Medicare (44 ± 13 days), and 61% of PPO (41 ± 12 days) patients. CONCLUSIONS: Compared to PPO and Medicare patients, HMO patients begin adjuvant radiation after surgery later and experience treatment delays in transitions of care between provider types and with referrals to specialists. Delaying radiation after 6 weeks of surgery is a known prognostic factor, with insurance type playing a possible role. Further investigation is required to identify insurance type as an independent risk factor of delayed access to care for HNSCC. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:E587-E592, 2020.


Assuntos
Neoplasias de Cabeça e Pescoço/economia , Sistemas Pré-Pagos de Saúde/estatística & dados numéricos , Medicare/estatística & dados numéricos , Organizações de Prestadores Preferenciais/estatística & dados numéricos , Carcinoma de Células Escamosas de Cabeça e Pescoço/economia , Tempo para o Tratamento/economia , Idoso , Feminino , Neoplasias de Cabeça e Pescoço/terapia , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Fatores de Tempo , Estados Unidos
15.
JAMA Otolaryngol Head Neck Surg ; 145(8): 716-722, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31219508

RESUMO

IMPORTANCE: Diagnostic flexible laryngoscopy (DFL) is the second-most reimbursed procedure by Medicare in otolaryngology. However, the economic trends of this procedure on a population level are unknown. OBJECTIVE: To describe national- and state-level DFL and videolaryngostroboscopy (VLS) utilization and payment trends from 2000 to 2016 in the Medicare population. DESIGN, SETTING, AND PARTICIPANTS: This population-based, cross-sectional study of all Medicare beneficiaries from 2000 through 2016 found that at the national level the total absolute number of DFLs performed in the US Medicare population increased by 87% from 344 183 to 645 172 services, whereas total absolute payments for DFLs made by Medicare concurrently increased by 41% from $38 720 243 to $54 499 071. Rates of DLS and VLS categorized as Current Procedural Terminology (CPT) code 31575 and 31579, respectively. Analysis was carried out between November 18, 2018 and December 18, 2018. EXPOSURES: Diagnostic flexible laryngoscopy and VLS. MAIN OUTCOMES AND MEASURES: The DFL and VLS utilization rates, payments, and reimbursement rate trends were analyzed by year and state. Utilization was assessed for physician characteristics, including specialty and credentials. RESULTS: Nationally from 2000 to 2016 in the Medicare population, DFL utilization per Medicare enrollee increased 30% from 0.0087 to 0.0110 and payment per enrollee decreased 2% from $0.98 to $0.96, whereas VLS utilization and payment per enrollee both increased at least 300% during the same time period, with VLS procedure per enrollee and payment per enrollee increasing by 382% from 0.00028 to 0.0013 and 301% from $0.05 to $0.22, respectively. There was a weak correlation between reimbursement and utilization per enrollee for both DFL (r = 0.23; 95% CI, 0.12-0.34) and VLS (r = 0.26; 95% CI, 0.14-0.37) performed from 2012 to 2016. In 2016, the mean (SD) payment per DFL was $85.14 ($7.95), ranging from $65.45 in Puerto Rico to $104.82 in Washington, DC, a 1.6-fold difference. For VLS, there was a 2-fold difference between the lowest-reimbursing state, Maine ($92.20) and the highest, New York ($182.96). All US dollar values were uniformly adjusted for inflation to 2018 dollar values. Most DFLs in 2016 were performed by otolaryngologists (93.6%). CONCLUSIONS AND RELEVANCE: The DFL utilization rates remained stable compared with VLS in the Medicare population from 2000 to 2016. There was a decrease in both DFL and VLS payments per procedure in the same time period and also weak correlations between reimbursement and utilization. Practice patterns and reimbursement varied geographically across the United States, though VLS exhibited significantly higher variation than DFL at the state level.

16.
J Neurosurg ; : 1-5, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30554187

RESUMO

OBJECTIVEThe present study aims to assess the clinical utility of a previously validated intraoperative meningioma consistency grading scale and its association with extent of resection (EOR) and various surgical outcomes.METHODSThe previously validated grading system was prospectively assessed in 127 consecutive patients undergoing open craniotomy for meningioma by multiple neurosurgeons at two high-volume academic hospitals from 2013 to 2016. Consistency grading scores ranging from 1 (soft) to 5 (firm/calcified) were retrospectively analyzed to test for association with surgical outcomes and EOR, categorized as gross-total resection (GTR) or subtotal resection, defined by postoperative MRI.RESULTSOne hundred twenty-seven patients were included in the analysis with a tumor consistency distribution as follows: grade 1, 3.1%; grade 2, 14.2%; grade 3, 44.1%; grade 4, 32.3%; and grade 5, 6.3%. The mean tumor diameter was 3.6 ± 1.7 cm. Tumor consistency grades were grouped into soft (grades 1 and 2), average (grade 3), and firm (grades 4 and 5) groups for statistical analysis with distributions of 17.3%, 44.1%, and 38.6%, respectively. There was no association between meningioma consistency and maximal tumor diameter, or location. Mean duration of surgery was longer for tumors with higher consistency: grades 1 and 2, 186 minutes; grade 3, 219 minutes; and grades 4 and 5, 299 minutes (p = 0.000028). There was a trend toward higher perioperative complication rates for tumors of increased consistency: grades 1 and 2, 4.5%; grade 3, 7.0%; and grades 4 and 5, 20.8% (p = 0.047). The proportion of GTR for each consistency group was as follows: grades 1 and 2, 77%; grade 3, 68%; and grades 4 and 5, 43% (p = 0.0062).CONCLUSIONSIn addition to other important meningioma characteristics such as invasiveness, tumor consistency is a key determinant of surgical outcomes, including operative duration and EOR. Future studies predicting tumor consistency based on preoperative neuroimaging will help considerably with preoperative planning for meningiomas.

17.
J Cereb Blood Flow Metab ; 37(10): 3278-3299, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28816095

RESUMO

Traumatic brain injury (TBI) is an expanding public health epidemic with pathophysiology that is difficult to diagnose and thus treat. TBI biomarkers should assess patients across severities and reveal pathophysiology, but currently, their kinetics and specificity are unclear. No single ideal TBI biomarker exists. We identified new candidates from a TBI CSF proteome by selecting trauma-released, astrocyte-enriched proteins including aldolase C (ALDOC), its 38kD breakdown product (BDP), brain lipid binding protein (BLBP), astrocytic phosphoprotein (PEA15), glutamine synthetase (GS) and new 18-25kD-GFAP-BDPs. Their levels increased over four orders of magnitude in severe TBI CSF. First post-injury week, ALDOC levels were markedly high and stable. Short-lived BLBP and PEA15 related to injury progression. ALDOC, BLBP and PEA15 appeared hyper-acutely and were similarly robust in severe and mild TBI blood; 25kD-GFAP-BDP appeared overnight after TBI and was rarely present after mild TBI. Using a human culture trauma model, we investigated biomarker kinetics. Wounded (mechanoporated) astrocytes released ALDOC, BLBP and PEA15 acutely. Delayed cell death corresponded with GFAP release and proteolysis into small GFAP-BDPs. Associating biomarkers with cellular injury stages produced astroglial injury-defined (AID) biomarkers that facilitate TBI assessment, as neurological deficits are rooted not only in death of CNS cells, but also in their functional compromise.


Assuntos
Astrócitos/patologia , Biomarcadores/análise , Lesões Encefálicas Traumáticas/líquido cefalorraquidiano , Proteínas Reguladoras de Apoptose , Astrócitos/química , Concussão Encefálica , Lesões Encefálicas Traumáticas/diagnóstico , Células Cultivadas , Proteína 7 de Ligação a Ácidos Graxos/sangue , Frutose-Bifosfato Aldolase/sangue , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/sangue , Cinética , Fosfoproteínas/sangue , Proteoma/análise , Proteínas Supressoras de Tumor/sangue
18.
J Alzheimers Dis ; 56(3): 1015-1036, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28035937

RESUMO

Mammalian target of rapamycin complex 1 (mTORC1), a nutrient sensor and central controller of cell growth and proliferation, is altered in various models of Alzheimer's disease (AD). Even less studied or understood in AD is mammalian target of rapamycin complex 2 (mTORC2) that influences cellular metabolism, in part through the regulations of Akt/PKB and SGK. Dysregulation of insulin/PI3K/Akt signaling is another important feature of AD pathogenesis. We found that both total mTORC1 and C2 protein levels and individual C1 and C2 enzymatic activities were decreased in human AD brain samples. In two rodent AD models, mTORC1 and C2 activities were also decreased. In a neuronal culture model of AD characterized by accumulation of cellular amyloid-ß (Aß)42, mTORC1 activity was reduced. Autophagic vesicles and markers were correspondingly increased and new protein synthesis was inhibited, consistent with mTORC1 hypofunction. Interestingly, mTORC2 activity in neural culture seemed resistant to the effects of intracellular amyloid. In various cell lines, Aß expression provoked insulin resistance, characterized by inhibition of stimulated Akt phosphorylation, and an increase in negative mTORC1 regular, p-AMPK, itself a nutrient sensor. Rapamycin decreased phospho-mTOR and to lesser degree p-Rictor. This further suppression of mTORC1 activity protected cells from Aß-induced toxicity and insulin resistance. More striking, Rictor over-expression fully reversed the Aß-effects on primary neuronal cultures. Finally, using in vitro assay, Rictor protein addition completely overcame oligomeric Aß-induced inhibition of the PDK-Akt activation step. We conclude that striking a new balance by restoring mTORC2 abundance and/or inhibition of mTORC1 has therapeutic potential in AD.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Córtex Cerebral/metabolismo , Resistência à Insulina/fisiologia , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Neurônios/metabolismo , Fragmentos de Peptídeos/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Animais , Autofagia/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Córtex Cerebral/patologia , Feminino , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos Transgênicos , Pessoa de Meia-Idade , Neurônios/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley
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