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1.
J Cell Sci ; 135(12)2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35583107

RESUMO

Capping protein Arp2/3 myosin I linker (CARMIL) proteins are multi-domain scaffold proteins that regulate actin dynamics by regulating the activity of capping protein (CP). Here, we characterize CARMIL-GAP (GAP for GTPase-activating protein), a Dictyostelium CARMIL isoform that contains a ∼130 residue insert that, by homology, confers GTPase-activating properties for Rho-related GTPases. Consistent with this idea, this GAP domain binds Dictyostelium Rac1a and accelerates its rate of GTP hydrolysis. CARMIL-GAP concentrates with F-actin in phagocytic cups and at the leading edge of chemotaxing cells, and CARMIL-GAP-null cells exhibit pronounced defects in phagocytosis and chemotactic streaming. Importantly, these defects are fully rescued by expressing GFP-tagged CARMIL-GAP in CARMIL-GAP-null cells. Finally, rescue with versions of CARMIL-GAP that lack either GAP activity or the ability to regulate CP show that, although both activities contribute significantly to CARMIL-GAP function, the GAP activity plays the bigger role. Together, our results add to the growing evidence that CARMIL proteins influence actin dynamics by regulating signaling molecules as well as CP, and that the continuous cycling of the nucleotide state of Rho GTPases is often required to drive Rho-dependent biological processes.


Assuntos
Proteínas de Capeamento de Actina , Dictyostelium , Proteínas de Capeamento de Actina/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Proteínas de Transporte/metabolismo , Dictyostelium/genética , Dictyostelium/metabolismo , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo
2.
Klin Monbl Augenheilkd ; 240(1): 13-23, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36706766

RESUMO

This article aims to present the differential diagnostics of benign and malignant eyelid tumours. The most common malignant eyelid tumour is basal cell carcinoma, followed by squamous cell carcinoma. The common signs of malignity are loss of lashes, ulceration, and infiltration of the lesion. Often the clinical appearance is various and therefore only a histological analysis gives the proper diagnosis. For most tumours, surgical resection is the gold standard of therapy. The reconstruction of the defects should be performed by an experienced oculoplastic surgeon. In malignant tumours that require large safety margins, the defect can be easily very large, and the reconstruction must then be performed with advanced ophthalmic plastic reconstruction techniques.


Assuntos
Carcinoma Basocelular , Neoplasias Palpebrais , Procedimentos de Cirurgia Plástica , Neoplasias Cutâneas , Humanos , Neoplasias Palpebrais/diagnóstico , Neoplasias Palpebrais/cirurgia , Diagnóstico Diferencial , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Carcinoma Basocelular/diagnóstico , Carcinoma Basocelular/cirurgia
3.
FASEB J ; 35(1): e21092, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33378124

RESUMO

Myosin 18Aα is a myosin 2-like protein containing unique N- and C-terminal protein interaction domains that co-assembles with myosin 2. One protein known to bind to myosin 18Aα is ß-Pix, a guanine nucleotide exchange factor (GEF) for Rac1 and Cdc42 that has been shown to promote dendritic spine maturation by activating the assembly of actin and myosin filaments in spines. Here, we show that myosin 18A⍺ concentrates in the spines of cerebellar Purkinje neurons via co-assembly with myosin 2 and through an actin binding site in its N-terminal extension. miRNA-mediated knockdown of myosin 18A⍺ results in a significant defect in spine maturation that is rescued by an RNAi-immune version of myosin 18A⍺. Importantly, ß-Pix co-localizes with myosin 18A⍺ in spines, and its spine localization is lost upon myosin 18A⍺ knockdown or when its myosin 18A⍺ binding site is deleted. Finally, we show that the spines of myosin 18A⍺ knockdown Purkinje neurons contain significantly less F-actin and myosin 2. Together, these data argue that mixed filaments of myosin 2 and myosin 18A⍺ form a complex with ß-Pix in Purkinje neuron spines that promotes spine maturation by enhancing the assembly of actin and myosin filaments downstream of ß-Pix's GEF activity.


Assuntos
Espinhas Dendríticas/metabolismo , Miosinas/metabolismo , Células de Purkinje/metabolismo , Fatores de Troca de Nucleotídeo Guanina Rho/metabolismo , Animais , Espinhas Dendríticas/genética , Deleção de Genes , Camundongos , Miosina Tipo II/genética , Miosina Tipo II/metabolismo , Miosinas/genética , Fatores de Troca de Nucleotídeo Guanina Rho/genética
4.
Soc Psychiatry Psychiatr Epidemiol ; 57(5): 1039-1047, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35022820

RESUMO

PURPOSE: Suicide among hospitality workers has recently attracted attention in the media. To date, little is known about suicide among hospitality workers in Australia. METHODS: Suicide data were obtained from the National Coronial Information System (NCIS). Occupational suicide rates were calculated using the Australian Bureau of Statistics population-level data from the 2011 census. Negative binomial regression, univariate logistic regression, and multivariate logistic regression were used to estimate the association between suicide and employment as a hospitality worker over the period 2006-2017, compared to all other occupations. RESULTS: Suicide rates for chefs was significantly higher than for persons in non-hospitality occupations [incidence rate ratio (IRR), 3.93; 95% CI 2.53-5.79; P < 0.001]. The interaction between occupation and sex was examined with follow-up testing. Suicide rates for female chefs were significantly higher than for females in non-hospitality occupations (IRR, 3.93; 95% CI 2.60-5.94). Suicide rates for male chefs were also significantly higher than males in non-hospitality occupations (IRR, 1.38; 95% CI 1.14-1.67). Compared with non-hospitality occupations, hospitality workers who died by suicide had significantly greater odds of being female (OR 0.63, 95% CI 0.50-0.79), residing in residential Socio-Economic Indexes for Areas (SEIFA) classified as most disadvantaged (OR 1.62, 95% CI 1.19-2.20), and being born outside of Australia (OR 1.74, 95% CI 1.34-2.25). CONCLUSION: Results indicate the need for targeted prevention of suicide by Australian hospitality workers. Overall, results suggest that specific hospitality occupations present a higher risk of suicidal behaviour than other non-hospitality occupations.


Assuntos
Suicídio , Austrália/epidemiologia , Feminino , Humanos , Masculino , Ocupações , Fatores de Risco , Ideação Suicida
5.
Klin Monbl Augenheilkd ; 238(5): 609-615, 2021 May.
Artigo em Alemão | MEDLINE | ID: mdl-31416097

RESUMO

Retrobulbar haematoma (RBH) is a rare complication that may affect vision after a trauma or a surgical procedure. The diagnosis must be made promptly, as only early surgical intervention can adequately prevent irreversible visual impairment. Because of the bony orbital walls, there is hardly any room for the increasing intraorbital volume due to the retrobulbar haemorrhage. This leads to an increase in intraorbital pressure and subsequently to compression of the optic nerve. Symptoms include disorders in ocular motility, ophthalmoplegia, diplopia, conjunctival chemosis, subconjunctival haemorrhage, proptosis, increased intraocular pressure, deterioration in visual acuity, decreased direct pupillary reflex, and a relative afferent pupillary defect. If the cause is traumatic or iatrogenic, prompt lateral canthotomy with cantholysis is the treatment of choice, and successfully lowers pressure in most cases. It can be performed in the emergency room by an ophthalmologist and may even be indicated without previous imaging. As the reconstruction of cantholysis is generally uncomplicated, we recommend performing the procedure when RBH is suspected. If canthotomy with cantholysis does not lead to adequate improvement, surgical orbital decompression must be performed. Supportive treatment should always include systemic steroids.


Assuntos
Hemorragia Retrobulbar , Descompressão Cirúrgica , Hematoma/diagnóstico , Hematoma/etiologia , Hematoma/cirurgia , Humanos , Hemorragia Retrobulbar/diagnóstico , Hemorragia Retrobulbar/etiologia , Hemorragia Retrobulbar/cirurgia , Transtornos da Visão/diagnóstico , Transtornos da Visão/etiologia , Acuidade Visual
6.
J Stroke Cerebrovasc Dis ; 29(9): 105018, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32807433

RESUMO

INTRODUCTION: Recent clinical comparisons of M1 and M2 segment endovascular thrombectomy have reached incongruous results in rates of complication and functional outcomes. This study aims to clarify the controversy surrounding this rapidly advancing technique through literature review and meta-analysis. METHODS: A Pubmed search was performed (January 2015-September 2019) using the following keywords: "M2 AND ("stroke" OR "occlusion") AND ("thrombectomy" OR "endovascular")". Safety and clinical outcomes were compared between segments via weighted Student's t-test, Chi-square and odds ratio while study heterogeneity was analyzed using Cochran Q and I2 tests. RESULTS: Pubmed identified 208 articles and eleven studies were included after full-text analysis, comprising 2,548 M1 and 758 M2 mechanical thrombectomy segment cases. Baseline National Institutes of Health Stroke Scale scores were comparatively lower in patients experiencing an M2 occlusion (16 ± 1.25 vs 13.6 ± 0.96, p < 0.01). Patients who underwent M2 mechanical thrombectomy were more likely to experience both good clinical outcomes (modified Rankin Scale 0-2) (48.6% vs 43.5% respectively, OR 1.24; CI 1.05-1.47, p = 0.01) and excellent clinical outcomes (modified Rankin Scale 0-1) (34.7% vs. 26.5%%, OR 1.6; CI 1.28-1.99, p < 0.01) at 90 days compared to M1 mechanical thrombectomy. Neither recanalization rates (75.3% vs 72.8%, OR 0.92, CI 0.75-1.13, p = 0.44) nor symptomatic intracranial hemorrhage rates (5.6% vs 4.9%, OR 0.92; CI 0.61-1.39, p= 0.7) were significantly different between M1 and M2 cohorts. Mortality was less frequent in the M2 cohort compared to M1 (16.3% vs 20.7%, OR 0.73; CI 0.57-0.94, p = 0.01). M1 and M2 cohorts did not differ in symptom onset-to-puncture (238.1 ± 46.7 vs 239.8 ± 43.9 min respectively, p=0.488) nor symptom onset-to recanalization times (318.7 ± 46.6 vs 317.7 ± 71.1 min respectively, p = 0.772), though mean operative duration was shorter in the M2 cohort (61.8 ± 25.5 vs 54.6 ± 24 min, p < 0.01). CONCLUSIONS: Patients who underwent M2 mechanical thrombectomy had a higher prevalence of good and excellent clinical outcomes compared to the M1 mechanical thrombectomy cohorts. Additionally, our data suggest lower mortality rates in the M2 cohort and symptomatic intracranial hemorrhage rates that are similar to the M1 cohort. Therefore, M2 segment thrombectomy likely does not pose a significantly elevated operative risk and may have a positive impact on patient outcomes.


Assuntos
Procedimentos Endovasculares/efeitos adversos , Infarto da Artéria Cerebral Média/terapia , Trombectomia/efeitos adversos , Idoso , Avaliação da Deficiência , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Infarto da Artéria Cerebral Média/diagnóstico , Infarto da Artéria Cerebral Média/mortalidade , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Recuperação de Função Fisiológica , Medição de Risco , Fatores de Risco , Trombectomia/mortalidade , Fatores de Tempo , Resultado do Tratamento
7.
Cerebellum ; 18(3): 406-421, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30729383

RESUMO

While mixed primary cerebellar cultures prepared from embryonic tissue have proven valuable for dissecting structure-function relationships in cerebellar Purkinje neurons (PNs), this technique is technically challenging and often yields few cells. Recently, mouse embryonic stem cells (mESCs) have been successfully differentiated into PNs, although the published methods are very challenging as well. The focus of this study was to simplify the differentiation of mESCs into PNs. Using a recently described neural differentiation media, we generate monolayers of neural progenitor cells from mESCs and differentiate them into PN precursors using specific extrinsic factors. These PN precursors are then differentiated into mature PNs by co-culturing them with granule neuron (GN) precursors also derived from neural progenitors using different extrinsic factors. The morphology of mESC-derived PNs is indistinguishable from PNs grown in primary culture in terms of gross morphology, spine length, and spine density. Furthermore, mESC-derived PNs express Calbindin D28K, IP3R1, IRBIT, PLCß4, PSD93, and myosin IIB-B2, all of which are either PN-specific or highly expressed in PNs. Moreover, we show that mESC-derived PNs form synapses with GN-like cells as in primary culture, express proteins driven by the PN-specific promoter Pcp2/L7, and exhibit the defect in spine ER inheritance seen in PNs isolated from dilute-lethal (myosin Va-null) mice when expressing a Pcp2/L7-driven miRNA directed against myosin Va. Finally, we define a novel extracellular matrix formulation that reproducibly yields monolayer cultures conducive for high-resolution imaging. Our improved method for differentiating mESCs into PNs should facilitate the dissection of molecular mechanisms and disease phenotypes in PNs.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Neurais/citologia , Células de Purkinje/citologia , Animais , Técnicas de Cultura de Células , Camundongos , Camundongos Endogâmicos C57BL
8.
Proc Natl Acad Sci U S A ; 113(43): E6610-E6619, 2016 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-27791032

RESUMO

Capping Protein (CP) plays a central role in the creation of the Arp2/3-generated branched actin networks comprising lamellipodia and pseudopodia by virtue of its ability to cap the actin filament barbed end, which promotes Arp2/3-dependent filament nucleation and optimal branching. The highly conserved protein V-1/Myotrophin binds CP tightly in vitro to render it incapable of binding the barbed end. Here we addressed the physiological significance of this CP antagonist in Dictyostelium, which expresses a V-1 homolog that we show is very similar biochemically to mouse V-1. Consistent with previous studies of CP knockdown, overexpression of V-1 in Dictyostelium reduced the size of pseudopodia and the cortical content of Arp2/3 and induced the formation of filopodia. Importantly, these effects scaled positively with the degree of V-1 overexpression and were not seen with a V-1 mutant that cannot bind CP. V-1 is present in molar excess over CP, suggesting that it suppresses CP activity in the cytoplasm at steady state. Consistently, cells devoid of V-1, like cells overexpressing CP described previously, exhibited a significant decrease in cellular F-actin content. Moreover, V-1-null cells exhibited pronounced defects in macropinocytosis and chemotactic aggregation that were rescued by V-1, but not by the V-1 mutant. Together, these observations demonstrate that V-1 exerts significant influence in vivo on major actin-based processes via its ability to sequester CP. Finally, we present evidence that V-1's ability to sequester CP is regulated by phosphorylation, suggesting that cells may manipulate the level of active CP to tune their "actin phenotype."


Assuntos
Proteínas de Capeamento de Actina/genética , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Dictyostelium/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas de Protozoários/genética , Pseudópodes/metabolismo , Proteínas de Capeamento de Actina/metabolismo , Proteína 2 Relacionada a Actina/genética , Proteína 2 Relacionada a Actina/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Proteína 3 Relacionada a Actina/genética , Proteína 3 Relacionada a Actina/metabolismo , Actinas/genética , Actinas/metabolismo , Sequência de Aminoácidos , Animais , Quimiotaxia/genética , Sequência Conservada , Dictyostelium/genética , Dictyostelium/ultraestrutura , Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Cinética , Camundongos , Mutação , Fosforilação , Pinocitose/genética , Ligação Proteica , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas de Protozoários/metabolismo , Pseudópodes/genética , Pseudópodes/ultraestrutura , Alinhamento de Sequência , Transdução de Sinais
9.
Biochim Biophys Acta Biomembr ; 1860(6): 1394-1402, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29621495

RESUMO

The cell-penetrating peptide (CPP) Pep-1 presents a great potential in drug delivery due to its intrinsic property to cross plasma membrane. However, its mechanism of entry into the cell remains unresolved. In this study, we compare the selectivity of Pep-1 towards vesicles mimicking normal and cancer cell membranes. The interaction was performed in a wide range of peptide-to-lipid molar ratios using infrared (IR), fluorescence, scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. At low peptide concentration, fluorescence experiments show that lipid-phosphatidylserine (PS) seems to enable Pep-1 translocation into cancer cell membrane as evidenced by the blue shift of its maximal emission wavelength. DSC data show that Pep-1 induces segregation of lipids. At high peptide concentration, IR data indicate that the interaction of Pep-1 is relatively stronger with normal cell membrane than with cancer cell membrane through the phosphate groups, while the interaction is weaker with normal cell membrane than with cancer cell membrane through the carbonyl groups. TGA and DSC data reveal that vesicles of normal cell membrane are thermally more stable than vesicles of cancer cell membrane. This suggests that the additional lipid PS included in cancer cell membrane has a destabilizing effect on the membrane structure. SEM images reveal that Pep-1 form superstructures including spherical particles and fibrils in the presence of both model membranes. PS seems to enhance peptide transport across cellular membranes. The biophysical techniques in this study provide valuable insights into the properties of CPPs in drug delivery systems.


Assuntos
Peptídeos Penetradores de Células/farmacologia , Cisteamina/análogos & derivados , Lipossomos , Peptídeos/farmacologia , Sequência de Aminoácidos , Varredura Diferencial de Calorimetria , Membrana Celular/química , Membrana Celular/efeitos dos fármacos , Peptídeos Penetradores de Células/química , Cisteamina/química , Cisteamina/farmacologia , Relação Dose-Resposta a Droga , Lisina/química , Lipídeos de Membrana/química , Microscopia Eletrônica de Varredura , Neoplasias/química , Peptídeos/química , Fosfatos/análise , Estrutura Secundária de Proteína , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termogravimetria
10.
Bioact Mater ; 26: 52-63, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36875050

RESUMO

Abdominal aortic aneurysm (AAA) is a progressive aortic dilatation, causing ∼80% mortality upon rupture. Currently, there is no approved drug therapy for AAA. Surgical repairs are invasive and risky and thus not recommended to patients with small AAAs which, however, account for ∼90% of the newly diagnosed cases. It is therefore a compelling unmet clinical need to discover effective non-invasive strategies to prevent or slow down AAA progression. We contend that the first AAA drug therapy will only arise through discoveries of both effective drug targets and innovative delivery methods. There is substantial evidence that degenerative smooth muscle cells (SMCs) orchestrate AAA pathogenesis and progression. In this study, we made an exciting finding that PERK, the endoplasmic reticulum (ER) stress Protein Kinase R-like ER Kinase, is a potent driver of SMC degeneration and hence a potential therapeutic target. Indeed, local knockdown of PERK in elastase-challenged aorta significantly attenuated AAA lesions in vivo. In parallel, we also conceived a biomimetic nanocluster (NC) design uniquely tailored to AAA-targeting drug delivery. This NC demonstrated excellent AAA homing via a platelet-derived biomembrane coating; and when loaded with a selective PERK inhibitor (PERKi, GSK2656157), the NC therapy conferred remarkable benefits in both preventing aneurysm development and halting the progression of pre-existing aneurysmal lesions in two distinct rodent models of AAA. In summary, our current study not only establishes a new intervention target for mitigating SMC degeneration and aneurysmal pathogenesis, but also provides a powerful tool to facilitate the development of effective drug therapy of AAA.

11.
Biochemistry ; 51(11): 2199-212, 2012 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-22352759

RESUMO

We developed molecular models for the cystic fibrosis transmembrane conductance regulator chloride channel based on the prokaryotic ABC transporter, Sav1866. Here we analyze predicted pore geometry and side-chain orientations for TM3, TM6, TM9, and TM12, with particular attention being paid to the location of the rate-limiting barrier for anion conduction. Side-chain orientations assayed by cysteine scanning were found to be from 77 to 90% in accord with model predictions. The predicted geometry of the anion conduction path was defined by a space-filling model of the pore and confirmed by visualizing the distribution of water molecules from a molecular dynamics simulation. The pore shape is that of an asymmetric hourglass, comprising a shallow outward-facing vestibule that tapers rapidly toward a narrow "bottleneck" linking the outer vestibule to a large inner cavity extending toward the cytoplasmic extent of the lipid bilayer. The junction between the outer vestibule and the bottleneck features an outward-facing rim marked by T338 in TM6 and I1131 in TM12, consistent with the observation that cysteines at both of these locations reacted with both channel-permeant and channel-impermeant, thiol-directed reagents. Conversely, cysteines substituted for S341 in TM6 or T1134 in TM12, predicted by the model to lie below the rim of the bottleneck, were found to react exclusively with channel-permeant reagents applied from the extracellular side. The predicted dimensions of the bottleneck are consistent with the demonstrated permeation of Cl(-), pseudohalide anions, water, and urea.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/química , Modelos Moleculares , Animais , Ânions , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Humanos , Transporte de Íons , Simulação de Dinâmica Molecular , Oócitos/metabolismo , Conformação Proteica , Xenopus laevis
12.
Mol Pharmacol ; 82(6): 1042-55, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22923500

RESUMO

High-throughput screening has led to the identification of small-molecule blockers of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel, but the structural basis of blocker binding remains to be defined. We developed molecular models of the CFTR channel on the basis of homology to the bacterial transporter Sav1866, which could permit blocker binding to be analyzed in silico. The models accurately predicted the existence of a narrow region in the pore that is a likely candidate for the binding site of an open-channel pore blocker such as N-(2-naphthalenyl)-[(3,5-dibromo-2,4-dihydroxyphenyl)methylene]glycine hydrazide (GlyH-101), which is thought to act by entering the channel from the extracellular side. As a more-stringent test of predictions of the CFTR pore model, we applied induced-fit, virtual, ligand-docking techniques to identify potential binding sites for GlyH-101 within the CFTR pore. The highest-scoring docked position was near two pore-lining residues, Phe337 and Thr338, and the rates of reactions of anionic, thiol-directed reagents with cysteines substituted at these positions were slowed in the presence of the blocker, consistent with the predicted repulsive effect of the net negative charge on GlyH-101. When a bulky phenylalanine that forms part of the predicted binding pocket (Phe342) was replaced with alanine, the apparent affinity of the blocker was increased ∼200-fold. A molecular mechanics-generalized Born/surface area analysis of GlyH-101 binding predicted that substitution of Phe342 with alanine would substantially increase blocker affinity, primarily because of decreased intramolecular strain within the blocker-protein complex. This study suggests that GlyH-101 blocks the CFTR channel by binding within the pore bottleneck.


Assuntos
Canais de Cloreto/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Glicina/análogos & derivados , Hidrazinas/metabolismo , Hidrazinas/farmacologia , Alanina/metabolismo , Animais , Sítios de Ligação , Cisteína/metabolismo , Glicina/metabolismo , Glicina/farmacologia , Oócitos/metabolismo , Xenopus laevis
13.
World Neurosurg ; 160: e335-e343, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35032715

RESUMO

BACKGROUND: Sleep-wake disorders (SWDs) are associated with multiple systemic pathologies; however, the clinical risk that such disorders carry for spinal surgery patients is not well understood. In the present population-based study, we comprehensively evaluated the significance of sleep-related risk factors on instrumented spinal surgery outcomes. METHODS: National Inpatient Sample data for the hospitalization of patients who had undergone elective instrumented spine surgery from 2008 to 2014 were analyzed using national estimates. The cohorts were defined as those admissions with or without a coexisting SWD diagnosis identified by International Classification of Diseases, ninth revision, codes. Postoperative complications, mortality rate, length of stay, discharge status, and the total cost of admission were compared between the groups using bivariate and multivariate analyses. RESULTS: A coexisting SWD was present in 234,640 of 2,171,167 instrumented spinal surgery hospitalizations (10.8%). Multivariate binary logistic regression accounting for these variables confirmed that a SWD is a significant risk factor for postoperative complications (odds ratio [OR], 1.160; 95% confidence interval [CI], 1.140-1.179; P < 0.0001), length of stay greater than the 75th percentile (OR, 1.303; 95% CI, 1.288-1.320; P < 0.0001), nonroutine discharge (OR, 1.147; 95% CI, 1.131-1.163; P < 0.0001), and death (OR, 1.533; 95% CI, 1.131-2.078; P < 0.01), but not for total charges greater than the 75th percentile (OR, 0.975; 95% CI, 0.962-0.989; P < 0.001). CONCLUSIONS: SWDs confer an increased risk of morbidity and mortality for elective instrumented spine surgery. Understanding the specific contributions of SWDs to postoperative morbidity and mortality will help physicians implement prophylactic measures to reduce complications and improve postoperative patient recovery.


Assuntos
Fusão Vertebral , Coluna Vertebral , Procedimentos Cirúrgicos Eletivos , Humanos , Tempo de Internação , Procedimentos Neurocirúrgicos , Complicações Pós-Operatórias/epidemiologia , Sono
14.
Front Cardiovasc Med ; 9: 949262, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211542

RESUMO

Abdominal aortic aneurysm (AAA) is a prevalent vascular disease with high mortality rates upon rupture. Despite its prevalence in elderly populations, there remain limited treatment options; invasive surgical repair, while risky, is the only therapeutic intervention with proven clinical benefits. Dietary factors have long been suggested to be closely associated with AAA risks, and dietary therapies recently emerged as promising avenues to achieve non-invasive management of a wide spectrum of diseases. However, the role of dietary therapies in AAA remains elusive. In this article, we will summarize the recent clinical and pre-clinical efforts in understanding the therapeutic and mechanistic implications of various dietary patterns and therapeutic approaches in AAA.

15.
J Cell Sci ; 122(Pt 21): 3856-61, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19808887

RESUMO

Type I myosins are monomeric motors involved in a range of motile and sensory activities in different cell types. In simple unicellular eukaryotes, motor activity of class I myosins is regulated by phosphorylation of a conserved 'TEDS site' residue within the motor domain. The mechanism by which this phosphorylation event affects the cellular function of each myosin I remains unclear. The fission yeast myosin I, Myo1, activates Arp2/3-dependent polymerisation of cortical actin patches and also regulates endocytosis. Using mutants and Myo1-specific antibodies, we show that the phosphorylation of the Myo1 TEDS site (serine 361) plays a crucial role in regulating this protein's dynamic localisation and cellular function. We conclude that although phosphorylation of serine 361 does not affect the ability of this motor protein to promote actin polymerisation, it is required for Myo1 to recruit to sites of endocytosis and function during this process.


Assuntos
Proteínas de Transporte/metabolismo , Endocitose , Cadeias Pesadas de Miosina/química , Cadeias Pesadas de Miosina/metabolismo , Proteínas de Schizosaccharomyces pombe/química , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/metabolismo , Quinases Ativadas por p21/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Proteínas de Transporte/genética , Dados de Sequência Molecular , Cadeias Pesadas de Miosina/genética , Fosforilação , Proteínas Serina-Treonina Quinases , Transporte Proteico , Schizosaccharomyces/química , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/genética , Alinhamento de Sequência , Quinases Ativadas por p21/genética
16.
Front Microbiol ; 12: 721004, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512600

RESUMO

Circadian rhythms, referring to 24-h daily oscillations in biological and physiological processes, can significantly regulate host immunity to pathogens, as well as commensals, resulting in altered susceptibility to disease development. Furthermore, vaccination responses to microbes have also shown time-of-day-dependent changes in the magnitude of protective immune responses elicited in the host. Thus, understanding host circadian rhythm effects on both gut bacteria and viruses during infection is important to minimize adverse effects on health and identify optimal times for therapeutic administration to maximize therapeutic success. In this review, we summarize the circadian modulations of gut bacteria, viruses and their interactions, both in health and during infection. We also discuss the importance of chronotherapy (i.e., time-specific therapy) as a plausible therapeutic administration strategy to enhance beneficial therapeutic responses.

17.
J Control Release ; 338: 295-306, 2021 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-34416322

RESUMO

The long-term success of endovascular intervention has long been overshadowed by vessel re-occlusion, also known as restenosis. Mainstream anti-restenotic devices, such as drug-eluting stent (DES) and drug-coated balloon (DCB), were recently shown with suboptimal performances and life-threatening complications, thereby underpinning the urgent need for alternative strategies with enhanced efficacy and safety profile. In our current study, we engineered a multimodal nanocluster formed by self-assembly of unimolecular nanoparticles and surface coated with platelet membrane, specifically tailored for precision drug delivery in endovascular applications. More specifically, it incorporates the combined merits of platelet membrane coating (lesion targetability and biocompatibility), reactive oxygen species (ROS)-detonable "cluster-bomb" chemistry (to trigger the large-to-small size transition at the target site, thereby achieving longer circulation time and higher tissue penetration), and sustained drug release. Using RVX-208 (an emerging anti-restenotic drug under clinical trials) as the model payload, we demonstrated the superior performances of our nanocluster over conventional poly(lactic-co-glycolic acid) (PLGA) nanoparticle. In cultured vascular smooth muscle cell (VSMC), the drug-loaded nanocluster induced effective inhibition of proliferation and protective gene expression (e.g., APOA-I) with a significantly reduced dosage of RVX-208 (1 µM). In a rat model of balloon angioplasty, intravenous injection of Cy5.5-tagged nanocluster led to greater lesion targetability, improved biodistribution, and deeper penetration into injured vessel walls featuring enriched ROS. Moreover, in contrast to either free drug solution or drug-loaded PLGA nanoparticle formulation, a single injection with the drug-loaded nanocluster (10 mg/kg of RVX-208) was sufficient to substantially mitigate restenosis. Additionally, this nanocluster also demonstrated biocompatibility according to in vitro cytotoxicity assay and in vivo histological and tissue qPCR analysis. Overall, our multimodal nanocluster offers improved targetability, tissue penetration, and ROS-responsive release over conventional nanoparticles, therefore making it a highly promising platform for development of next-generation endovascular therapies.


Assuntos
Reestenose Coronária , Stents Farmacológicos , Animais , Biomimética , Materiais Revestidos Biocompatíveis , Ratos , Espécies Reativas de Oxigênio , Distribuição Tecidual
18.
Cureus ; 12(4): e7694, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32431973

RESUMO

We present our experience following a unique case of coincident intracranial hemorrhage and comminuted fractures of both the squamous temporal bone and zygomaticofrontal orbit. Surgical techniques and outcome for this presentation have yet to be sufficiently described. A 55-year-old male presented following trauma with Glasgow Coma Scale score of 7. Radiographic evaluation revealed comminuted fractures of the squamous temporal bone with extension into the lateral orbit, along with zygomatic process fracture extending 2.5 cm medially into the orbital roof. Zygomaticofrontal orbital roof fragments reached superiorly into the middle cranial fossa and inferiorly into the orbit. Surgical intervention was deemed necessary to address underlying epidural hematoma, subarachnoid hemorrhage, correction of cranial bone defects, and decompression of the optic nerve and other intraorbital nerves. A frontotemporal approach was employed. Repair of temporal and orbital fractures was accomplished using a combination of wire mesh screws and titanium miniplates. Postoperative imaging demonstrated bony approximation and successful evacuation of traumatic hemorrhage. The patient remains functionally and neurologically intact apart from a sluggishly responsive left eye presumed to result from a left optic nerve or ciliary ganglion lesion. Although rapid reconstruction of complex cranial-orbital trauma and hematoma evacuation can permit acceptable gross functional neurological outcome following massive trauma, orbital fracture and subsequent hemorrhagic processes may be the nidus of neurological sequelae in this complex traumatic constellation. Thus, alterations in surgical approach and reconstruction are appropriate in order to maximize neurological function while supporting restoration of cosmetic space.

20.
PLoS One ; 15(4): e0227496, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267864

RESUMO

Atlantic salmon migrate to sea following completion of a developmental process known as smolting, which establishes a seawater (SW) tolerant phenotype. Smolting is stimulated by exposure to long photoperiod or continuous light (LL) following a period of exposure to short photoperiod (SP), and this leads to major changes in gill ion exchange and osmoregulatory function. Here, we performed an RNAseq experiment to discover novel genes involved in photoperiod-dependent remodeling of the gill. This revealed a novel cohort of genes whose expression rises dramatically in fish transferred to LL following SP exposure, but not in control fish maintained continuously on LL or on SP. A follow-up experiment revealed that the SP-history dependence of LL induction of gene expression varies considerably between genes. Some genes were inducible by LL exposure after only 2 weeks exposure to SP, while others required 8 weeks prior SP exposure for maximum responsiveness to LL. Since subsequent SW growth performance is also markedly improved following 8 weeks SP exposure, these photoperiodic history-dependent genes may be useful predictive markers for full smolt development.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Fotoperíodo , Salmo salar/fisiologia , Tolerância ao Sal/genética , Água do Mar/efeitos adversos , Migração Animal/fisiologia , Animais , Brânquias/crescimento & desenvolvimento , Estágios do Ciclo de Vida/fisiologia , Noruega , RNA-Seq , Fatores de Tempo
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