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1.
Plast Surg (Oakv) ; 32(1): 158-161, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38433801

RESUMO

When intraorbital wooden foreign bodies are missed, the consequences can be devastating. While the gold standard diagnostic imaging is computed tomography (CT), it has low sensitivity. We present a 61-year-old man with a bamboo injury to his right eye. He underwent two CT scans that failed to raise the possibility of intraorbital foreign bodies. Upon additional review, a rectangular-shaped pocket of air was identified in the orbit which was most consistent with wooden foreign bodies based on the clinical history. A combined mid-lid approach followed by a transconjunctival and transcaruncular extension were employed to remove several wooden splinters. Postoperatively, due to recurrent orbital compartment syndrome, he required a second decompression with an inferior rim osteotomy. He had good recovery at 3 months follow-up. Overall, intraorbital wooden foreign bodies are challenging to diagnose due to imaging limitations. Providing a clear history and suspected diagnosis to radiology is critical for diagnosis.


Manquer des corps étrangers intraorbitaires en bois peut avoir des conséquences désastreuses. L'imagerie diagnostique de référence est la tomodensitométrie (TDM) mais sa sensibilité est faible. Nous présentons le cas d'un homme de 61 ans ayant une plaie par morceau de bambou dans son œil droit. Il a bénéficié de deux tomodensitométrie qui n'ont pas réussi à donner l'alarme sur la possibilité de corps étrangers intraorbitaires. Lors d'un réexamen supplémentaire, une poche d'air de forme rectangulaire a été identifiée dans l'orbite; cette poche était très compatible avec des corps étrangers en bois, selon l'histoire clinique. Un abord combiné à mi-paupière, suivi d'une extension transconjonctivale et transcaronculaire, a été employé pour retirer plusieurs échardes en bois. En postopératoire, le patient a nécessité une deuxième décompression avec ostéotomie du bord inférieur en raison d'un syndrome du compartiment orbitaire récidivant. La récupération a été bonne au suivi de trois mois. Globalement, les corps étrangers intraorbitaires en bois sont difficiles à diagnostiquer en raison des limites de l'imagerie. Fournir au radiologue une histoire claire et un diagnostic suspecté est essentiel au diagnostic.

2.
Gastrointest Endosc ; 99(5): 676-687.e16, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38272274

RESUMO

BACKGROUND AND AIMS: Randomized controlled trials (RCTs) have reported that artificial intelligence (AI) improves endoscopic polyp detection. Different methodologies-namely, parallel and tandem designs-have been used to evaluate the efficacy of AI-assisted colonoscopy in RCTs. Systematic reviews and meta-analyses have reported a pooled effect that includes both study designs. However, it is unclear whether there are inconsistencies in the reported results of these 2 designs. Here, we aimed to determine whether study characteristics moderate between-trial differences in outcomes when evaluating the effectiveness of AI-assisted polyp detection. METHODS: A systematic search of Ovid MEDLINE, Embase, Cochrane Central, Web of Science, and IEEE Xplore was performed through March 1, 2023, for RCTs comparing AI-assisted colonoscopy with routine high-definition colonoscopy in polyp detection. The primary outcome of interest was the impact of study type on the adenoma detection rate (ADR). Secondary outcomes included the impact of the study type on adenomas per colonoscopy and withdrawal time, as well as the impact of geographic location, AI system, and endoscopist experience on ADR. Pooled event analysis was performed using a random-effects model. RESULTS: Twenty-four RCTs involving 17,413 colonoscopies (AI assisted: 8680; non-AI assisted: 8733) were included. AI-assisted colonoscopy improved overall ADR (risk ratio [RR], 1.24; 95% confidence interval [CI], 1.17-1.31; I2 = 53%; P < .001). Tandem studies collectively demonstrated improved ADR in AI-aided colonoscopies (RR, 1.18; 95% CI, 1.08-1.30; I2 = 0%; P < .001), as did parallel studies (RR, 1.26; 95% CI, 1.17-1.35; I2 = 62%; P < .001), with no statistical subgroup difference between study design. Both tandem and parallel study designs revealed improvement in adenomas per colonoscopy in AI-aided colonoscopies, but this improvement was more marked among tandem studies (P < .001). AI assistance significantly increased withdrawal times for parallel (P = .002), but not tandem, studies. ADR improvement was more marked among studies conducted in Asia compared to Europe and North America in a subgroup analysis (P = .007). Type of AI system used or endoscopist experience did not affect overall improvement in ADR. CONCLUSIONS: Either parallel or tandem study design can capture the improvement in ADR resulting from the use of AI-assisted polyp detection systems. Tandem studies powered to detect differences in endoscopic performance through paired comparison may be a resource-efficient method of evaluating new AI-assisted technologies.

4.
Virchows Arch ; 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37548751

RESUMO

Pre-analytical deficiencies (PADs) are a major source of errors in anatomical pathology, accounting for about 70% of laboratory deficiencies. These can lead to incorrect diagnoses, delayed treatments, and increased healthcare costs. As part of a quality improvement initiative, we retrospectively identified and characterized 237 PADs documented over a 1-year period in a tertiary care academic center. The most common PADs were errors in specimen procurement (56%), handling of samples within the lab (16%), accessioning (10%), incomplete requisitions (9%), and transportation-related issues (7%). Strategies were then devised to mitigate these errors. Categorization of pre- and intra-laboratory PADs was refined into eight categories (collection, requisition, specimen container, transportation, receiving, accessioning, preparation, and communications) in the laboratory information system. Mandatory PAD documentation was implemented for accessioning staff. Post-implementation, prospective analysis identified that the most common PADs were related to surgical requisitions (75%). Among these, missing ordering physician's signature was the most common, accounting for 67.7% of requisition-related PADs and 50.8% of all PADs. Other common PADs included incomplete information of specimens, clinical information, patient information, physician information, source location, collection time, incorrect requisition forms, and illegible handwritten information. This study highlights the importance of identifying and addressing PADs in the anatomical pathology laboratory setting as well as the potential benefits of implementing standardized documentation and quality improvement processes to address these deficiencies.

5.
Mol Cell Biol ; 42(9): e0024122, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36005752

RESUMO

Upon pathogen infection, intricate innate signaling cascades are induced to initiate the transcription of immune effectors, including cytokines and chemokines. Transcription factor EB (TFEB), a master regulator of lysosomal biogenesis and autophagy genes, was found recently to be a novel regulator of innate immunity in both Caenorhabditis elegans and mammals. Despite TFEB participating in critical mechanisms of pathogen recognition and in the transcriptional response to infection in mammalian macrophages, little is known about its roles in the infected epithelium or infected nonimmune cells in general. Here, we demonstrate that TFEB is activated in nonimmune cells upon infection with bacterial pathogens through a pathway dependent on mTORC1 inhibition and RAG-GTPase activity, reflecting the importance of membrane damage and amino acid starvation responses during infection. Additionally, we present data demonstrating that although TFEB does not affect bacterial killing or load in nonimmune cells, it alters the host transcriptome upon infection, thus promoting an antibacterial transcriptomic landscape. Elucidating the roles of TFEB in infected nonimmune cells and the upstream signaling cascade provides critical insight into understanding how cells recognize and respond to bacterial pathogens.


Assuntos
Aminoácidos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Aminoácidos/metabolismo , Animais , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Autofagia/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Caenorhabditis elegans/metabolismo , Citocinas/metabolismo , Células Epiteliais/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Lisossomos/metabolismo , Mamíferos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo
6.
Eye (Lond) ; 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672457

RESUMO

BACKGROUND: Diabetic retinopathy is a major complication of diabetes mellitus, where in its most advanced form ischemic changes lead to the development of retinal neovascularization, termed proliferative diabetic retinopathy (PDR). While the development of PDR is often associated with angiogenic and inflammatory cytokines, studies differ on which cytokines are implicated in disease pathogenesis and on the strength of these associations. We therefore conducted a systematic review and meta-analysis to quantitatively assess the existing body of data on intraocular cytokines as biomarkers in PDR. METHODS: A comprehensive search of the literature without year limitation was conducted to January 18, 2021, which identified 341 studies assessing vitreous or aqueous cytokine levels in PDR, accounting for 10379 eyes with PDR and 6269 eyes from healthy controls. Effect sizes were calculated as standardized mean differences (SMD) of cytokine concentrations between PDR and control patients. RESULTS: Concentrations (SMD, 95% confidence interval, and p-value) of aqueous IL-1ß, IL-6, IL-8, MCP-1, TNF-α, and VEGF, and vitreous IL-2, IL-4, IL-6, IL-8, angiopoietin-2, eotaxin, erythropoietin, GM-CSF, GRO, HMGB-1, IFN-γ, IGF, IP-10, MCP-1, MIP-1, MMP-9, PDGF-AA, PlGF, sCD40L, SDF-1, sICAM-1, sVEGFR, TIMP, TNF-α, and VEGF were significantly higher in patients with PDR when compared to healthy nondiabetic controls. For all other cytokines no differences, failed sensitivity analyses or insufficient data were found. CONCLUSIONS: This extensive list of cytokines speaks to the complexity of PDR pathogenesis, and informs future investigations into disease pathogenesis, prognosis, and management.

8.
Acta Ophthalmol ; 100(1): e53-e70, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33945678

RESUMO

Diabetic macular oedema (DME) is considered a chronic inflammatory disease associated with aberrations in many intraocular cytokines. Studies assessing the role of these cytokines as biomarkers in the diagnosis and management of DME have demonstrated inconsistent findings. We quantitatively summarized data related to 116 candidate aqueous and vitreous inflammatory cytokines as biomarkers in DME. A systematic search without year limitation was performed up to 19 October 2020. Studies were included if they provided data on aqueous or vitreous cytokine concentrations in patients with DME. Effect sizes were generated as standardized mean differences (SMDs) of cytokine concentrations between patients with DME and controls. Data were extracted from 128 studies that included 4163 study eyes with DME and 1281 control eyes. Concentrations (standard mean difference, 95% confidence interval and p-value) of aqueous IL-6 (1.28, 0.57-2.00, p = 0.004), IL-8 (1.06, 0.74-1.39, p < 0.00001), MCP-1 (1.36, 0.57-2.16, p = 0.0008) and VEGF (1.31, 1.01-1.62, p < 0.00001) and vitreous VEGF (2.27, 1.55-2.99, p < 0.00001) were significantly higher in patients with DME (n = 4163) compared to healthy controls (n = 1281). No differences, failed sensitivity analyses or insufficient data were found between patients with DME and healthy controls for the concentrations of the remaining cytokines. This analysis implicates multiple cytokine biomarker candidates other than VEGF in DME and clarifies previously reported inconsistent associations. As the therapeutic options for DME expand to include multiple agents with multiple targets, it will be critical to manage the treatment burden with tailored therapy that optimizes outcomes and minimizes treatment burden. Intraocular cytokines have the promise of providing a robust individualized assessment of disease status and response to therapy. We have identified key candidate cytokines that may serve as biomarkers in individualized treatment algorithms.


Assuntos
Humor Aquoso/metabolismo , Citocinas/metabolismo , Retinopatia Diabética/complicações , Inflamação/metabolismo , Edema Macular/metabolismo , Corpo Vítreo/metabolismo , Biomarcadores/metabolismo , Retinopatia Diabética/metabolismo , Humanos , Edema Macular/etiologia
9.
Acta Ophthalmol ; 100(5): e1163-e1171, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34694071

RESUMO

PURPOSE: Retinal displacement is common following rhegmatogenous retinal detachment (RRD) repair. A computer simulation was developed to assess forces applied by a gas tamponade of various sizes in the setting of pneumatic retinopexy (PnR) versus pars plana vitrectomy (PPV). DESIGN: Computer simulation model. METHODS: The contact angle and pressure between the tamponade and the retina were calculated using interfacial tension and the densities of gas and vitreous. A simulation determined the dynamics of fluid motion in the subretinal space and calculated deformations of the retina. RESULTS: Bulk flow of fluid away from the tamponade in a direction along gravity stretched the retina and caused displacement in the simulations. Extent of displacement is attributable to the subretinal fluid layer thickness, and area of contact and contact pressure applied by the tamponade. Larger gas tamponades have greater contact pressure applied to the retina. Reducing gas bubble size from 93% to 6.25% with PPV versus PnR, there was a 79% reduction in the mean contact pressure (1.4 mmHg-0.29 mmHg), and a 93% reduction in the surface area of contact (11 cm2 -0.8 cm2 ). Therefore, the contact force applied to the entire retina decreases by 97% from 83 mN (PPV) to 2.9 mN (PnR). The model resembling PnR had more than three times less displacement compared to PPV. CONCLUSIONS: This model provides a framework to study retinal displacement. Our findings suggest that proportional to their size, gas tamponades stretched the retina by displacing subretinal fluid following RRD repair.


Assuntos
Descolamento Retiniano , Simulação por Computador , Humanos , Retina/cirurgia , Descolamento Retiniano/etiologia , Descolamento Retiniano/cirurgia , Estudos Retrospectivos , Vitrectomia/efeitos adversos , Corpo Vítreo
10.
Case Rep Ophthalmol ; 12(1): 174-181, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33976678

RESUMO

Mitochondrial neurogastrointestinal encephalopathy disease (MNGIE) is a rare autosomal recessive condition characterized by gastrointestinal dysmotility, external ophthalmoplegia, leukoencephalopathy, and sensorimotor neuropathy. A 31-year-old man was referred for a 1-year history of horizontal diplopia related to a large exotropia from chronic progressive external ophthalmoplegia. MRI revealed a diffuse leukoencephalopathy and his 3-year history of chronic intermittent diarrhea, cachexia, and diffuse sensory more than motor peripheral neuropathy led to a unifying clinical diagnosis of MNGIE. This was later confirmed with genetic testing, which revealed a homozygous pathogenic mutation in the thymidine phosphorylase (TYMP) gene. His younger brother had an identical clinical syndrome and was similarly diagnosed. MNGIE diagnosis is important to establish to avoid unnecessary invasive testing for gastrointestinal, ophthalmological, and neurological symptoms and to ensure patients receive appropriate nutritional and genetic counselling. Gene therapy offers a potential future therapy for patients with this condition.

11.
Ophthalmol Retina ; 5(11): 1125-1138, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33482399

RESUMO

TOPIC: It is unclear whether differences exist in efficacy and safety between combined versus sequentially performed phacoemulsification and pars plana vitrectomy (phaco-PPV). CLINICAL RELEVANCE: This meta-analysis aimed to compare the efficacy and incidence of complications between these surgical methods. METHODS: Ovid MEDLINE, EMBASE, and Cochrane CENTRAL were searched for articles reporting the efficacy and safety of combined versus sequential phaco-PPV for any indication. The primary outcomes were postoperative best-corrected visual acuity (BCVA) and mean absolute refractive error from target (RET). Secondary outcomes included efficacy outcomes and postoperative complications. Meta-analysis was conducted using a random effects model in all cases. Risk of bias assessment was performed using the Cochrane risk of bias assessment tool for randomized trials and ROBINS-I tool for observational studies. RESULTS: Of the 5410 articles identified, 1 randomized controlled trial and 14 comparative studies were included, with 1407 and 951 eyes in the combined and sequential surgery groups, respectively. Mean age was 62.71 ± 6.16 years and 44% (range, 32.1%-70%) of eyes were from men. The mean baseline BCVA was 0.88 ± 0.59 logarithm of the minimum angle of resolution units (Snellen equivalent, 20/152). The meta-analysis showed no significance between groups in postoperative mean BCVA (P = 0.76) and mean absolute RET (P = 0.46). The risks of synechiae formation (risk ratio [RR], 2.74; 95% confidence interval [CI], 1.83-4.11; P < 0.001), fibrin formation (RR, 2.81; 95% CI, 1.84-4.30; P < 0.001), and intraoperative or postoperative retinal detachment (RR, 2.65; 95% CI, 1.08-6.47; P = 0.03) were significantly higher after combined surgery. However, the risks of posterior capsular tear (RR, 0.43; 95% CI, 0.25-0.73; P = 0.002) and macular hole nonclosure or reopening (RR, 0.18; 95% CI, 0.03-0.93; P = 0.04) were significantly lower in the combined group. DISCUSSION: No significant differences were found in visual and refractive outcomes between combined and sequential phaco-PPV, whereas differences existed in certain safety outcomes. These conclusions remain preliminary, as most evidence is derived from low- to moderate-quality retrospective studies. Given the variability in outcome reporting and associated heterogeneity, future randomized controlled trials are needed.


Assuntos
Catarata/complicações , Facoemulsificação/métodos , Complicações Pós-Operatórias/epidemiologia , Doenças Retinianas/cirurgia , Vitrectomia/métodos , Saúde Global , Humanos , Incidência , Doenças Retinianas/complicações
12.
J Neuroophthalmol ; 41(4): e752-e755, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33136664

RESUMO

ABSTRACT: A 24-year-old man presented with a 2-month history of progressive, painless vision loss in the right eye, with no history of headache, nasal congestion, rhinorrhea, or epistaxis. His visual acuity was counting fingers at 1 ft in the right eye and 20 of 20 in the left eye with a right relative afferent pupillary defect and mild temporal optic disc pallor. MRI of the brain and orbits showed a mass involving bilateral ethmoid and sphenoid sinuses and right nasal cavity. He underwent urgent extended endoscopic endonasal transsphenoidal approach for resection of the sinonasal skull base tumor and photon radiation therapy. Pathology revealed a well-differentiated cartilaginous neoplasm with focal areas of entrapped native bone, consistent with a chondrosarcoma WHO grade I/III. At 6-month follow-up after surgery, he had a visual acuity of 20/40 in the right eye and 20/20 in the left eye. Malignant tumors from the sinonasal area should be kept in the differential diagnosis for compressive optic neuropathies and may present with vision loss even in the absence of nasal or sinus symptoms.


Assuntos
Condrossarcoma , Doenças do Nervo Óptico , Adulto , Condrossarcoma/complicações , Condrossarcoma/diagnóstico , Condrossarcoma/cirurgia , Humanos , Masculino , Cavidade Nasal/cirurgia , Doenças do Nervo Óptico/diagnóstico , Doenças do Nervo Óptico/etiologia , Seio Esfenoidal , Transtornos da Visão/diagnóstico , Transtornos da Visão/etiologia , Adulto Jovem
13.
J Neurol Sci ; 419: 117190, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33075593

RESUMO

Apraclonidine is the most widely used pharmacologic agent to confirm Horner syndrome. It is a strong α-2 and a weak α-1 adrenergic agonist and reversal of anisocoria is considered a positive test. The utility of apraclonidine in acute Horner syndrome remains controversial as the exact timing for denervation sensitivity to develop remains unknown. The goal of this study was to describe the use of apraclonidine in the diagnosis of acute Horner syndrome in patients with an unequivocal onset within 7 days. We identified 3 patients who were referred to ophthalmology/neuro-ophthalmology service and had reversal of anisocoria within 7 days. Two cases of second-order Horner syndrome after cardiac surgery and a case of a third-order Horner syndrome from a carotid cavernous sinus fistula resulted in reversal of anisocoria 72 h, 48 h, and 5 days after onset. Photographic documentation was provided for all cases. Our results suggest that apraclonidine has utility in the acute period and positive results can be seen as early as 48 h after onset. Apraclonidine should therefore still be considered to confirm the presence of acute Horner syndrome before extensive neuroimaging is performed.


Assuntos
Síndrome de Horner , Agonistas alfa-Adrenérgicos , Clonidina/análogos & derivados , Síndrome de Horner/diagnóstico , Humanos , Motivação
14.
Eye Brain ; 12: 61-71, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32753994

RESUMO

Obstructive sleep apnea (OSA) is a disease of obstructed airways during sleep that significantly impacts the quality of life and increases the risk of various systemic diseases. OSA has been studied as a risk factor for a number of neuro-ophthalmic conditions and a strong relationship has been established with non-arteritic anterior ischemic optic neuropathy (NAION). The incidence of glaucoma and stroke have also been significantly associated with OSA and are conditions that may also be seen by neuro-ophthalmologists. Patients with NAION have a significantly higher incidence of OSA and OSA diagnosis significantly increases the risk for NAION development. Non-compliance with continuous positive airway pressure (CPAP) in OSA patients has also been found to be a risk factor for fellow-eye involvement and there is increasing evidence to suggest that every patient with NAION should be formally evaluated with polysomnography. The relationship between OSA and idiopathic intracranial hypertension (IIH) has also been studied, but the relationship between these two conditions is less clear. There is insufficient evidence to recommend routine eye examinations in OSA patients for papilledema and conducting a sleep study for a newly diagnosed IIH patient should be left to the discretion of the clinician based on other symptoms and risk factors of OSA.

16.
Science ; 365(6448)2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31273097

RESUMO

Multiple cytosolic innate sensors form large signalosomes after activation, but this assembly needs to be tightly regulated to avoid accumulation of misfolded aggregates. We found that the eIF2α kinase heme-regulated inhibitor (HRI) controls NOD1 signalosome folding and activation through a process requiring eukaryotic initiation factor 2α (eIF2α), the transcription factor ATF4, and the heat shock protein HSPB8. The HRI/eIF2α signaling axis was also essential for signaling downstream of the innate immune mediators NOD2, MAVS, and TRIF but dispensable for pathways dependent on MyD88 or STING. Moreover, filament-forming α-synuclein activated HRI-dependent responses, which suggests that the HRI pathway may restrict toxic oligomer formation. We propose that HRI, eIF2α, and HSPB8 define a novel cytosolic unfolded protein response (cUPR) essential for optimal innate immune signaling by large molecular platforms, functionally homologous to the PERK/eIF2α/HSPA5 axis of the endoplasmic reticulum UPR.


Assuntos
Citosol/enzimologia , Citosol/imunologia , Imunidade Inata , Proteínas Serina-Treonina Quinases/fisiologia , Resposta a Proteínas não Dobradas/imunologia , Fator 4 Ativador da Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Linhagem Celular , Chaperona BiP do Retículo Endoplasmático , Fator de Iniciação 2 em Eucariotos/metabolismo , Fibroblastos , Proteínas de Choque Térmico/metabolismo , Humanos , Listeria/imunologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Mutantes , Chaperonas Moleculares/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Proteína Adaptadora de Sinalização NOD1/química , Proteína Adaptadora de Sinalização NOD1/metabolismo , Proteína Adaptadora de Sinalização NOD2/metabolismo , Proteínas Serina-Treonina Quinases/genética , Salmonella/imunologia , Infecções por Salmonella , Shigella/imunologia , Transdução de Sinais
17.
Mol Cell Biol ; 39(10)2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30910794

RESUMO

Protein degradation pathways are critical for maintaining proper protein dynamics within the cell, and considerable efforts have been made toward the development of therapeutics targeting these catabolic processes. We report here that isoginkgetin, a naturally derived biflavonoid, sensitized cells undergoing nutrient starvation to apoptosis, induced lysosomal stress, and activated the lysosome biogenesis gene TFEB Isoginkgetin treatment led to the accumulation of aggregates of polyubiquitinated proteins that colocalized strongly with the adaptor protein p62, the 20S proteasome, and the endoplasmic reticulum-associated degradation (ERAD) protein UFD1L. Isoginkgetin directly inhibited the chymotrypsin-like, trypsin-like, and caspase-like activities of the 20S proteasome and impaired NF-κB signaling, suggesting that the molecule may display its biological activity in part through proteasome inhibition. Importantly, isoginkgetin was effective at killing multiple myeloma (MM) cell lines in vitro and displayed a higher rate of cell death induction than the clinically approved proteasome inhibitor bortezomib. We propose that isoginkgetin disturbs protein homeostasis, leading to an excess of protein cargo that places a burden on the lysosomes/autophagic machinery, eventually leading to cancer cell death.


Assuntos
Biflavonoides/farmacologia , Lisossomos/metabolismo , Mieloma Múltiplo/metabolismo , Inibidores de Proteassoma/farmacologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células HCT116 , Células HeLa , Homeostase/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisossomos/efeitos dos fármacos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos
18.
Front Immunol ; 9: 359, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29593709

RESUMO

Tonicity of saline (NaCl) is important in regulating cellular functions and homeostasis. Hypertonic saline is administered to treat many inflammatory diseases, including cystic fibrosis. Excess neutrophil extracellular trap (NET) formation, or NETosis, is associated with many pathological conditions including chronic inflammation. Despite the known therapeutic benefits of hypertonic saline, its underlying mechanisms are not clearly understood. Therefore, we aimed to elucidate the effects of hypertonic saline in modulating NETosis. For this purpose, we purified human neutrophils and induced NETosis using agonists such as diacylglycerol mimetic phorbol myristate acetate (PMA), Gram-negative bacterial cell wall component lipopolysaccharide (LPS), calcium ionophores (A23187 and ionomycin from Streptomyces conglobatus), and bacteria (Pseudomonas aeruginosa and Staphylococcus aureus). We then analyzed neutrophils and NETs using Sytox green assay, immunostaining of NET components and apoptosis markers, confocal microscopy, and pH sensing reagents. This study found that hypertonic NaCl suppresses nicotinamide adenine dinucleotide phosphate oxidase (NADPH2 or NOX2)-dependent NETosis induced by agonists PMA, Escherichia coli LPS (0111:B4 and O128:B12), and P. aeruginosa. Hypertonic saline also suppresses LPS- and PMA- induced reactive oxygen species production. It was determined that supplementing H2O2 reverses the suppressive effect of hypertonic saline on NOX2-dependent NETosis. Many of the aforementioned suppressive effects were observed in the presence of equimolar concentrations of choline chloride and osmolytes (d-mannitol and d-sorbitol). This suggests that the mechanism by which hypertonic saline suppresses NOX2-dependent NETosis is via neutrophil dehydration. Hypertonic NaCl does not significantly alter the intracellular pH of neutrophils. We found that hypertonic NaCl induces apoptosis while suppressing NOX2-dependent NETosis. In contrast, hypertonic solutions do not suppress NOX2-independent NETosis. Although hypertonic saline partially suppresses ionomycin-induced NETosis, it enhances A23187-induced NETosis, and it does not alter S. aureus-induced NETosis. Overall, this study determined that hypertonic saline suppresses NOX2-dependent NETosis induced by several agonists; in contrast, it has variable effects on neutrophil death induced by NOX2-independent NETosis agonists. These findings are important in understanding the regulation of NETosis and apoptosis in neutrophils.


Assuntos
Escherichia coli/fisiologia , Armadilhas Extracelulares/metabolismo , NADPH Oxidases/metabolismo , Neutrófilos/fisiologia , Pseudomonas aeruginosa/fisiologia , Solução Salina Hipertônica/metabolismo , Apoptose , Ionóforos de Cálcio/imunologia , Células Cultivadas , Desidratação , Diglicerídeos/imunologia , Humanos , Lipopolissacarídeos/imunologia , Espécies Reativas de Oxigênio/metabolismo , Acetato de Tetradecanoilforbol/imunologia
19.
Sci Rep ; 7(1): 3409, 2017 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-28611461

RESUMO

Neutrophils cast neutrophil extracellular traps (NETs) to ensnare microbial pathogens. Nevertheless, the molecular rheostats that regulate NETosis in response to bacteria are not clearly established. We hypothesized that stress-activated protein kinase or c-Jun N-terminal Kinase (SAPK/JNK) is a molecular switch that turns on NETosis in response to increasing concentrations of lipopolysaccharide (LPS)- and Gram-negative bacteria. Here we show that Escherichia coli LPS (0111:B4; 10-25 µg/ml), but not phorbol myristate acetate (PMA), activates JNK in human neutrophils in a dose-dependent manner. JNK inhibitors SP600125 and TCSJNK6o, and a TLR4 inhibitor TAK242 suppress reactive oxygen species production and NETosis in LPS-, but not PMA-treated neutrophils. Diphenyleneiodonium suppresses LPS-induced NETosis, confirming that endotoxin induces NADPH oxidase-dependent NETosis. Immunoblots, Sytox Green assays, and confocal microscopy of cleaved caspase-3 and nuclear morphology show that JNK inhibition does not induce apoptosis in LPS-stimulated neutrophils. JNK inhibition also suppresses NETosis induced by two typical Gram-negative bacteria, E. coli and Pseudomonas aeruginosa. Therefore, we propose that neutrophils use a TLR4-dependent, JNK-mediated molecular sensing mechanism to initiate NADPH oxidase-dependent suicidal NETosis in response to increasing concentrations of LPS, and Gram-negative bacteria. The LPS-TLR4-JNK activation axis determines the fate of these cells: to be or not to be NETotic neutrophils.


Assuntos
Apoptose , Armadilhas Extracelulares/imunologia , MAP Quinase Quinase 4/metabolismo , Neutrófilos/imunologia , Células Cultivadas , Escherichia coli/patogenicidade , Armadilhas Extracelulares/microbiologia , Humanos , Lipopolissacarídeos/imunologia , MAP Quinase Quinase 4/antagonistas & inibidores , NADPH Oxidases/metabolismo , Neutrófilos/microbiologia , Inibidores de Proteínas Quinases/farmacologia , Pseudomonas aeruginosa/patogenicidade
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