Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 210
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
EMBO J ; 41(16): e110410, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35698800

RESUMO

Although amyloid fibres are highly stable protein aggregates, a specific combination of human Hsp70 system chaperones can disassemble them, including fibres formed of α-synuclein, huntingtin, or Tau. Disaggregation requires the ATPase activity of the constitutively expressed Hsp70 family member, Hsc70, together with the J domain protein DNAJB1 and the nucleotide exchange factor Apg2. Clustering of Hsc70 on the fibrils appears to be necessary for disassembly. Here we use atomic force microscopy to show that segments of in vitro assembled α-synuclein fibrils are first coated with chaperones and then undergo bursts of rapid, unidirectional disassembly. Cryo-electron tomography and total internal reflection fluorescence microscopy reveal fibrils with regions of densely bound chaperones, preferentially at one end of the fibre. Sub-stoichiometric amounts of Apg2 relative to Hsc70 dramatically increase recruitment of Hsc70 to the fibres, creating localised active zones that then undergo rapid disassembly at a rate of ~ 4 subunits per second. The observed unidirectional bursts of Hsc70 loading and unravelling may be explained by differences between the two ends of the polar fibre structure.


Assuntos
Proteínas de Choque Térmico HSP70 , alfa-Sinucleína , Amiloide/metabolismo , Proteínas Amiloidogênicas/metabolismo , Proteínas de Choque Térmico HSC70/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Chaperonas Moleculares/metabolismo , Agregados Proteicos , Ligação Proteica , alfa-Sinucleína/metabolismo
2.
Circulation ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989565

RESUMO

BACKGROUND: Physician modified endografts (PMEGs) have been widely used in the treatment of complex abdominal aortic aneurysm and thoracoabdominal aortic aneurysm, however, previous data are limited to small single center studies and robust data on safety and effectiveness of PMEGs are lacking. We aimed to perform an international multicenter study analyzing the outcomes of PMEGs in complex abdominal aortic aneurysms and thoracoabdominal aortic aneurysms. METHODS: An international multicenter single-arm cohort study was performed analyzing the outcomes of PMEGs in the treatment of elective, symptomatic, and ruptured complex abdominal aortic aneurysms and thoracoabdominal aortic aneurysms. Variables and outcomes were defined according to the Society for Vascular Surgery reporting standards. Device modification and procedure details were collected and analyzed. Efficacy outcomes included technical success and safety outcomes included major adverse events and 30-day mortality. Follow-up outcomes included reinterventions, endoleaks, target vessel patency rates and overall and aortic-related mortality. Multivariable analysis was performed aiming at identifying predictors of technical success, 30-day mortality, and major adverse events. RESULTS: Overall, 1274 patients were included in the study from 19 centers. Median age was 74 (IQR, 68-79), and 75.7% were men; 45.7% were complex abdominal aortic aneurysms, and 54.3% were thoracoabdominal aortic aneurysms; 65.5% patients presented electively, 24.6% were symptomatic, and 9.9% were ruptured. Most patients (83.1%) were submitted to a fenestrated repair, 3.6% to branched repair, and 13.4% to a combined fenestrated and branched repair. Most patients (85.8%) had ≥3 target vessels included. The overall technical success was 94% (94% in elective, 93.4% in symptomatic, and 95.1% in ruptured cases). Thirty-day mortality was 5.8% (4.1% in elective, 7.6% in symptomatic, and 12.7% in ruptured aneurysms). Major adverse events occurred in 25.2% of cases (23.1% in elective, 27.8% in symptomatic, and 30.3% in ruptured aneurysms). Median follow-up was 21 months (5.6-50.6). Freedom from reintervention was 73.8%, 61.8%, and 51.4% at 1, 3, and 5 years; primary target vessel patency was 96.9%, 93.6%, and 90.3%. Overall survival and freedom from aortic-related mortality was 82.4%/92.9%, 69.9%/91.6%, and 55.0%/89.1% at 1, 3, and 5 years. CONCLUSIONS: PMEGs were a safe and effective treatment option for elective, symptomatic, and ruptured complex aortic aneurysms. Long-term data and future prospective studies are needed for more robust and detailed analysis.

3.
J Hum Genet ; 69(1): 13-18, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37848720

RESUMO

We performed genetic association study for genes encoding angiogenic and angiostatic proteins in patients with Takayasu arteritis (TAK). A total of 96 SNPs involving 60 genes were studied. Genotyping was performed in Fluidigm 96.96 Dynamic Array chip. All statistical analysis for SNP evaluation was performed using PLINK software. Initial analyses revealed five SNPs from three genes [IL-18 (encodes Interleukin-18), FGF2 (encodes Fibroblast Growth Factor-2), and ANGPT1 (encodes Angiopoietin-1)] as significantly different between controls and cases (uncorrected p < 0.05). After permutation-based analysis, two tag SNPs on the promoter region of IL-18 (rs187238 and rs1946518) and one 3'UTR tag SNP (rs1476217) of FGF2 were significantly associated with susceptibility to TAK, with p and OR (95% CI) of 0.0006 and 1.64 (1.25-2.17), 0.03 and 1.28 (1.02-1.64) & 0.016 and 1.33 (1.05-1.67), respectively; while, the two tag SNPs of ANGPT1 gene (rs6469101 and rs16875900) showed a trend (p = 0.055 & p = 0.051, respectively after permutation based correction). There is robust linkage disequilibrium between the two tag SNPs of IL-18 gene as validated by 1000 genome data of South Asian population; the eQTL effects of these tag SNPs of IL-18 and FGF2 genes on adjacent genes further suggest that these tag SNPs act as genetic risks for development of TAK in South Asians, with possible functional implications towards future biomarker development. Genotype phenotype study by genetic model-based analysis also revealed associations between genotype subsets and clinical features like fever, visual loss, left subclavian and coronary artery involvement in our TAK patients.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Arterite de Takayasu , Humanos , Fator 2 de Crescimento de Fibroblastos/genética , Interleucina-18/genética , Arterite de Takayasu/genética , Polimorfismo de Nucleotídeo Único , Angiogênese , Predisposição Genética para Doença
4.
J Endovasc Ther ; : 15266028241245345, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654600

RESUMO

PURPOSE: To present a novel technique that enables safe and effective cannulation of target vessels with challenging anatomy during fenestrated/branched endovascular aortic repair (F/B-EVAR). TECHNIQUE: Following deployment of the F/B-EVAR endograft, the target vessels (TVs) are cannulated. The bundle wire technique provides a solution to challenging TVs and uses multiple fine atraumatic guidewires that together serve as a stiff guidewire. The technique can be executed in 2 ways using: (1) one 0.018 inch and one 0.014 inch guidewire or (2) three 0.014 inch guidewires. We demonstrate the technique in a case of a complex abdominal aortic aneurysm treated using branched EVAR in which the left renal artery with severe ostial stenosis was catheterized using the bundle wire technique. CONCLUSIONS: The bundle wire technique offers a technically feasible and economically viable solution for facilitating catheter and bridging stent delivery in anatomically challenging TVs during F/B-EVAR. It is a useful addition to the therapeutic armamentarium available to physicians for accessing demanding TVs.

5.
J Phycol ; 60(2): 229-253, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38502571

RESUMO

Aero-terrestrial algae are ecologically and economically valuable bioresources contributing to carbon sequestration, sustenance of soil health, and fertility. Compared to aquatic algae, the literature on subaerial algae is minimal, including studies of distinctive habitats such as forest soils, agricultural fields, deserts, polar regions, specific subaerial zones, artificial structures, and tropical soils. The primary goal here was to identify the gaps and scope of research on such algae. Accordingly, the literature was analyzed per sub-themes, such as the "nature of current research data on terrestrial algae," "methodological approaches," "diversity," "environmental relationships," "ecological roles," and "economic significance." The review showed there is a high diversity of algae in soils, especially members belonging to the Cyanophyta (Cyanobacteria) and Chlorophyta. Algal distributions in terrestrial environments depend on the microhabitat conditions, and many species of soil algae are sensitive to specific soil conditions. The ecological significance of soil algae includes primary production, the release of biochemical stimulants and plant growth promoters into soils, nitrogen fixation, solubilization of minerals, and the enhancement and maintenance of soil fertility. Since aero-terrestrial habitats are generally stressed environments, algae of such environments can be rich in rare metabolites and natural products. For example, epilithic soil algae use wet adhesive molecules to fix them firmly on the substratum. Exploring the ecological roles and economic utility of soil and other subaerial algae could be helpful for the development of algae-based industries and for achieving sustainable soil management.


Assuntos
Clorófitas , Cianobactérias , Solo/química , Plantas/microbiologia , Ecossistema
6.
J Drugs Dermatol ; 23(4): 216-226, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38564399

RESUMO

BACKGROUND: Multiple treatment options exist for the management of moderate-to-severe acne. However, the comparative effectiveness (efficacy/safety) of moderate-to-severe acne treatments has not been systematically examined. METHODS: A systematic literature review (SLR) was conducted to identify randomized controlled trials of ≥4 weeks of treatment (topical, oral, physical, or combinations) for moderate-to-severe facial acne in patients aged ≥9 years. Efficacy outcomes included: percentage of patients achieving ≥2-grade reduction from baseline and “clear” or “almost clear” for global severity score (treatment success); absolute change in inflammatory (ILs reduction); and noninflammatory lesion counts (NILs reduction). A random-effects network meta-analysis (NMA) was conducted for the efficacy outcomes. Treatments were ranked with posterior rank plots and surface under cumulative ranking values.  Results: Eighty-five studies were included in the SLR/NMA. Topical triple-agent fixed-dose combination (FDC) gel (clindamycin phosphate 1.2%/adapalene 0.15%/benzoyl peroxide 3.1%) and combinations of double-agent fixed-dose topical treatments with oral antibiotics (TOA3) consistently ranked in the top 3 treatments. Topical triple-agent FDC gel was numerically superior to TOA3 for treatment success (log-odds ratios: 1.84 [95% credible interval (CrI) 1.36 to 2.29]) and 1.69 (95% CrI: 1.01 to 2.32) vs placebo/vehicle). TOA3 was numerically superior to topical triple-agent FDC gel for reduction of ILs (mean difference: -8.21 [-10.33 to -6.13]) and -10.40 [-13.44 to -7.14] vs placebo/vehicle) and NILs (mean difference: -13.41 [-16.69 to -10.32] and -17.74 [-22.56 to -12.85] vs placebo/vehicle). CONCLUSIONS: Based on this SLR/NMA, topical triple-agent FDC gel was the most efficacious and safe treatment for moderate-to-severe acne. J Drugs Dermatol. 2024;23(4):     doi:10.36849/JDD.8148.


Assuntos
Acne Vulgar , Combinação Adapaleno e Peróxido de Benzoil , Fármacos Dermatológicos , Humanos , Peróxido de Benzoíla , Acne Vulgar/diagnóstico , Acne Vulgar/tratamento farmacológico , Acne Vulgar/induzido quimicamente , Metanálise em Rede , Combinação de Medicamentos , Resultado do Tratamento , Géis/uso terapêutico
7.
Sensors (Basel) ; 24(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38257464

RESUMO

Surface-enhanced Raman spectroscopy (SERS) has been introduced to detect pesticides at low concentrations and in complex matrices to help developing countries monitor pesticides to keep their concentrations at safe levels in food and the environment. SERS is a surface-sensitive technique that enhances the Raman signal of molecules absorbed on metal nanostructure surfaces and provides vibrational information for sample identification and quantitation. In this work, we report the use of silver nanostars (AgNs) as SERS-active elements to detect four neonicotinoid pesticides (thiacloprid, imidacloprid, thiamethoxam and nitenpyram). The SERS substrates were prepared with multiple depositions of the nanostars using a self-assembly approach to give a dense coverage of the AgNs on a glass surface, which ultimately increased the availability of the spikes needed for SERS activity. The SERS substrates developed in this work show very high sensitivity and excellent reproducibility. Our research opens an avenue for the development of portable, field-based pesticide sensors, which will be critical for the effective monitoring of these important but potentially dangerous chemicals.

8.
Biometrics ; 79(4): 3586-3598, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36594642

RESUMO

Sponsors often rely on multi-regional clinical trials (MRCTs) to introduce new treatments more rapidly into the global market. Many commonly used statistical methods do not account for regional differences, and small regional sample sizes frequently result in lower estimation quality of region-specific treatment effects. The International Council for Harmonization E17 guidelines suggest consideration of methods that allow for information borrowing across regions to improve estimation. In response to these guidelines, we develop a novel methodology to estimate global and region-specific treatment effects from MRCTs with time-to-event endpoints using Bayesian model averaging (BMA). This approach accounts for the possibility of heterogeneous treatment effects between regions, and we discuss how to assess the consistency of these effects using posterior model probabilities. We obtain posterior samples of the treatment effects using a Laplace approximation, and we show through simulation studies that the proposed modeling approach estimates region-specific treatment effects with lower mean squared error than a Cox proportional hazards model while resulting in a similar rejection rate of the global treatment effect. We then apply the BMA approach to data from the LEADER trial, an MRCT designed to evaluate the cardiovascular safety of an anti-diabetic treatment.


Assuntos
Modelos Estatísticos , Projetos de Pesquisa , Teorema de Bayes , Tamanho da Amostra , Simulação por Computador
9.
J Appl Microbiol ; 134(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37230947

RESUMO

Arbuscular mycorrhizal fungi (AMF) are effective natural alternatives to assist plants in improving crop productivity and immunity against pests and diseases. However, a comprehensive idea of the variables under which they show optimum activity, especially concerning particular soil, climate, geography, and crop characteristics, has yet to be adequately standardized. Since paddy is the staple food for half of the world's population, such standardization is highly significant globally. Research concerning determinants affecting AMF functioning in rice is limited. However, the identified variables include external variables such as abiotic, biotic, and anthropogenic factors and internal variables such as plant and AMF characteristics. Among the abiotic factors, edaphic factors like soil pH, phosphorus availability, and soil moisture significantly affect AMF functioning in rice. In addition, anthropogenic influences such as land use patterns, flooding, and fertilizer regimes also affect AMF communities in rice agroecosystems. The principal objective of the review was to analyse the existing literature on AMF concerning such variables generally and to assess the specific research requirements on variables affecting AMF in rice. The ultimate goal is to identify research gaps for applying AMF as a natural alternative in the sustainable agriculture of paddy with optimum AMF symbiosis enhancing rice productivity.


Assuntos
Micorrizas , Oryza , Raízes de Plantas/microbiologia , Microbiologia do Solo , Fungos , Agricultura , Solo , Oryza/microbiologia
10.
Qual Life Res ; 32(9): 2573-2585, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37212941

RESUMO

PURPOSE: The aim of this study was to generate evidence supporting the development and content validity of a new PRO instrument, the Small Intestinal Bacterial Overgrowth (SIBO) Symptom Measure (SSM) daily diary. The SSM assesses symptom severity in SIBO patients, with the ultimate goal of providing a fit for purpose PRO for endpoint measurement. METHODS: Qualitative research included 35 SIBO patients in three study stages, using a hybrid concept elicitation (CE)/cognitive interview (CI) method with US patients, ≥ 18 years. Stage 1 included a literature review, clinician interviews, and initial CE interviews with SIBO patients to identify symptoms important to patients for inclusion in the SSM. Stage 2 included hybrid CE/CI to learn more about patients' SIBO experience and test the draft SSM. Finally, stage 3 used CIs to refine the instrument and test its content validity. RESULTS: In stage 1 (n = 8), 15 relevant concepts were identified, with items drafted based on the literature review/clinician interviews and elicitation work. Within stage 2 (n = 15), the SSM was refined to include 11 items; with wording revised for three items. Stage 3 (n = 12) confirmed the comprehensiveness of the SSM, as well as appropriateness of the item wording, recall period, and response scale. The resulting 11-item SSM assesses the severity of bloating, abdominal distention, abdominal discomfort, abdominal pain, flatulence, physical tiredness, nausea, diarrhea, constipation, appetite loss, and belching. CONCLUSIONS: This study provides evidence supporting the content validity of the new PRO. Comprehensive patient input ensures that the SSM is a well-defined measure of SIBO, ready for psychometric validation studies.


Assuntos
Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Humanos , Qualidade de Vida/psicologia , Pesquisa Qualitativa , Psicometria , Exame Físico
11.
J Drugs Dermatol ; 22(10): 1033-1039, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37801539

RESUMO

BACKGROUND: Acne has psychosocial effects on patient's quality of life (QoL). This post hoc exploratory analysis of pooled phase 3 data assessed the impact of investigational IDP-126 gel (for moderate to severe acne) on the Acne-Specific Quality of Life Questionnaire (Acne-QoL; exploratory endpoint in the trials).  Methods: A post hoc exploratory analysis using pooled data (N=309; age ≥13 years) was conducted to assess if 1) changes from baseline to week 12 in Acne-QoL domain scores significantly differ by treatment; 2) differences were clinically meaningful, and 3) relative importance of acne severity as measured by the Evaluator's Global Severity Score (EGSS) or lesion counts explains the changes in QoL (Acne-QoL).  Results: Acne-QoL domain scores significantly (P<0.001, each) improved for patients treated with IDP-126 Gel vs vehicle in all four domains (role-emotional [least squares mean difference {LSMean} 4.1], self-perception [LSMean 3.8], acne symptoms [LSMean 2.6], and role-social [LSMean 2.0]). The proportion of responders was significantly higher (P<0.05, each) in the IDP-126 Gel group vs vehicle across Acne-QoL domains, self-perception (odds ratio [OR]: 4.32), acne symptoms (OR: 3.90), role-social (OR: 3.59), and role-emotional (OR: 2.50). Across all Acne QoL domains, the improvement on the EGSS endpoint (53.8-63.3%) was more likely to influence QoL improvements than the inflammatory (20.1-33.4%) and non-inflammatory lesion (9.5-18.7%) counts.  Conclusions: This post hoc exploratory analysis of pooled phase 3 data (moderate to severe acne) suggests that treatment with IDP 126 Gel led to statistically significant and clinically meaningful improvements in QoL and improvement in QoL was primarily influenced by EGSS.J Drugs Dermatol. 2023;22(10):1033-1039      doi:10.36849/JDD.7812.


Assuntos
Acne Vulgar , Géis , Adolescente , Humanos , Acne Vulgar/diagnóstico , Acne Vulgar/tratamento farmacológico , Acne Vulgar/patologia , Qualidade de Vida , Índice de Gravidade de Doença , Resultado do Tratamento , Ensaios Clínicos Fase III como Assunto
12.
J Endovasc Ther ; 29(6): 893-903, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35021904

RESUMO

PURPOSE: To achieve accurate rotational orientation and the axial position of unconstrained triple-fenestrated physician-modified endografts upon deployment in the aortic arch during total arch thoracic endovascular aortic repair (TA-TEVAR). MATERIALS AND METHODS: Following a detailed study of reconstructed computerized tomography angiography images of patients' arch anatomy, customized, sealable fenestrations with radio-opaque margins are created onsite on Valiant Captivia (Medtronic) endografts, transposing the arch branch ostial anatomic interrelationship onto the endograft precisely. Radio-opaque figure-of-8 markers, indicating the 12 o'clock (superior) position, are attached to the endograft on the surface and brought up to the surface under the endograft cover during resheathing. Resheathing without any twist in the endograft is achieved by lining up the welds in each endograft stent segment in a straight line. The fluoroscopic working view for arch endograft delivery and deployment is the left anterior oblique view that is orthogonal to the plane of the arch, which, in turn, is the right anterior oblique view in which parts of a stiff indwelling guidewire in the ascending and descending aorta precisely overlap. During introduction in the working view, the endograft delivery system is rotated in the descending thoracic aorta so that the 12 o'clock figure-of-8 markers are viewed on the edge and situated at the outer aortic curvature; continued advancement into the arch without any further rotation will ensure superior orientation of the figure-of-8 markers and, consequently, correct endograft rotational orientation. Proper axial endograft positioning requires locating the left common carotid artery (LCCA) fenestration just proximal to a taut externalized LCCA-femoral guidewire loop marking the posterior limit of the LCCA ostium. After endograft deployment during rapid cardiac pacing, the target arch branches are cannulated through their respective fenestrations using hydrophilic 0.035-inch guidewires that are externalized via distal sheaths to create femoral-arch branch (through-and-through) loops over which covered fenestrated stents are introduced and deployed. RESULTS: This technique was used successfully in 31 consecutive patients undergoing TA-TEVAR; systemic blood pressure was obtained in all arch branches immediately after endograft deployment, indicating adequate blood flow. All arch branches were successfully cannulated and stented. CONCLUSION: This system enables accurate deployment of unconstrained triple-fenestrated arch endografts simply and reliably during TA-TEVAR.


Assuntos
Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Prótese Vascular , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/métodos , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Desenho de Prótese , Resultado do Tratamento , Stents
13.
Value Health ; 25(10): 1705-1716, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36055922

RESUMO

OBJECTIVES: Suprachoroidal injection of triamcinolone acetonide is the first Food and Drug Administration-approved treatment for macular edema associated with uveitis. A cost-effectiveness analysis was performed comparing this treatment with best supportive care (BSC) for the management of this indication from US Medicare and commercial payer perspectives. METHODS: A patient-level simulation was developed per the patient characteristics and changes in best-corrected visual acuity letter scores observed in a phase III study of triamcinolone acetonide (PEACHTREE). The wholesale acquisition cost of triamcinolone acetonide was $1650/injection; suprachoroidal injection cost was assumed at $200/injection. Healthcare costs were informed by a US claims-based analysis. Mortality risk associated with severe vision loss and blindness was modeled by applying a hazard ratio to all-cause mortality rates of the US general population. Health-related quality of life weights, obtained from a regression model fitted to the Visual Function Questionnaire-25 data from PEACHTREE, were applied based on the best-corrected visual acuity scores of both eyes. Costs (2020 US dollar) and benefits were discounted at 3% annually. Incremental cost-effectiveness ratios were estimated over a 10-year horizon. RESULTS: In the base-case, the incremental cost-effectiveness ratio comparing triamcinolone acetonide with BSC was $28 479 per quality-adjusted life-year gained. The wholesale acquisition cost for triamcinolone acetonide for suprachoroidal use was ∼68%, ∼56%, and ∼27% below the willingness-to-pay thresholds of $150 000, $100 000, and $50 000 per quality-adjusted life-year gained, respectively. Results were robust in sensitivity and scenario analyses. CONCLUSIONS: Triamcinolone acetonide for suprachoroidal use is cost-effective compared with BSC for patients with macular edema associated with uveitis.


Assuntos
Edema Macular , Uveíte , Idoso , Análise Custo-Benefício , Glucocorticoides/uso terapêutico , Humanos , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Medicare , Qualidade de Vida , Resultado do Tratamento , Triancinolona Acetonida/uso terapêutico , Estados Unidos , Uveíte/complicações , Uveíte/tratamento farmacológico , Acuidade Visual
14.
Sensors (Basel) ; 22(23)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36501946

RESUMO

This paper presents the first implementation of a spiking neural network (SNN) for the extraction of cepstral coefficients in structural health monitoring (SHM) applications and demonstrates the possibilities of neuromorphic computing in this field. In this regard, we show that spiking neural networks can be effectively used to extract cepstral coefficients as features of vibration signals of structures in their operational conditions. We demonstrate that the neural cepstral coefficients extracted by the network can be successfully used for anomaly detection. To address the power efficiency of sensor nodes, related to both processing and transmission, affecting the applicability of the proposed approach, we implement the algorithm on specialised neuromorphic hardware (Intel ® Loihi architecture) and benchmark the results using numerical and experimental data of degradation in the form of stiffness change of a single degree of freedom system excited by Gaussian white noise. The work is expected to open a new direction of SHM applications towards non-Von Neumann computing through a neuromorphic approach.


Assuntos
Algoritmos , Redes Neurais de Computação , Computadores
15.
Genes Dev ; 28(11): 1179-90, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24888589

RESUMO

During V(D)J recombination of immunoglobulin genes, p53 and nonhomologous end-joining (NHEJ) suppress aberrant rejoining of DNA double-strand breaks induced by recombinase-activating genes (Rags)-1/2, thus maintaining genomic stability and limiting malignant transformation during B-cell development. However, Rag deficiency does not prevent B-cell leukemogenesis in p53/NHEJ mutant mice, revealing that p53 and NHEJ also suppress Rag-independent mechanisms of B-cell leukemogenesis. Using several cytogenomic approaches, we identified a novel class of activating mutations in Fms-like tyrosine kinase 3 (Flt3), a receptor tyrosine kinase important for normal hematopoiesis in Rag/p53/NHEJ triple-mutant (TM) B-cell leukemias. These mutant Flt3 alleles were created by complex genomic rearrangements with Moloney leukemia virus (MuLV)-related endogenous retroviral (ERV) elements, generating ERV-Flt3 fusion genes encoding an N-terminally truncated mutant form of Flt3 (trFlt3) that was transcribed from ERV long terminal repeats. trFlt3 protein lacked most of the Flt3 extracellular domain and induced ligand-independent STAT5 phosphorylation and proliferation of hematopoietic progenitor cells. Furthermore, expression of trFlt3 in p53/NHEJ mutant hematopoietic progenitor cells promoted development of clinically aggressive B-cell leukemia. Thus, repetitive MuLV-related ERV sequences can participate in aberrant end-joining events that promote development of aggressive B-cell leukemia.


Assuntos
Linfócitos B/citologia , Leucemia/genética , Vírus da Leucemia Murina de Moloney/genética , Recombinação Genética , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo , Animais , Linfócitos B/patologia , Proliferação de Células , Reparo do DNA por Junção de Extremidades/genética , Regulação Leucêmica da Expressão Gênica , Células-Tronco Hematopoéticas/citologia , Leucemia/patologia , Camundongos , Vírus da Leucemia Murina de Moloney/metabolismo , Mutação , Fosforilação , Estrutura Terciária de Proteína , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
16.
Mod Rheumatol ; 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36542822

RESUMO

OBJECTIVE: To compare the clinical and angiographic responses of Mycophenolate Mofetil (MMF) versus Methotrexate (MTX) in Takayasu arteritis (TAK). METHODS: This was a open label, outcome assessor blinded trial. Adult patients of TAK with active disease were randomized 1:1 to MMF 1g twice daily or MTX 20 mg once weekly, by computer generated program. All patients were started on 0.5 mg/kg of steroids with a predetermined tapering protocol. Primary outcome was treatment response as defined by Indian Takayasu arteritis score at 9 months. Secondary end points included time to first failure and angiographic progression. RESULTS: A total of 52 patients (26 in each arm) were recruited. The rate of responders was 71.43% (15/21) in the MMF arm and 63.64% (14/22) in the MTX arm (p=0.58). The median time to 1st failure was 9 months (Range: 3-9) and 4.5 months (range: 3-9) in the MMF and MTX arm respectively (p=0.052). In both groups, 15 % of patients (n=3) had progressive disease in angiography. CONCLUSION: The results showed numerically better outcomes towards MMF, with a longer time to first failure than Methotrexate(9 months versus 4.5 months, p=0.052). No significant difference was seen in the angiographic outcomes.

17.
Rheumatology (Oxford) ; 60(5): 2246-2255, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33179052

RESUMO

OBJECTIVES: To describe the clinical profile of Asian Indian patients with Takayasu's arteritis (TAK) and to compare clinical features and outcome of childhood-onset Takayasu's arteritis (cTAK) with adult-onset TAK (aTAK). METHODS: Data related to clinical features and response to treatment of patients with cTAK (age of onset <16 years) and aTAK from a large observational cohort in our tertiary care teaching hospital were noted and compared. RESULTS: Altogether, 602 patients (cTAK = 119; aTAK = 483) were studied. Patients with cTAK had a blunted female: male ratio; but fever, elevated acute phase reactants, involvement of abdominal aorta or its branches, hypertension, abdominal pain, elevated serum creatinine and cardiomyopathy were more common in cTAK as compared with aTAK. Patients with aTAK were more likely to have aortic-arch disease and claudication than cTAK. During follow-up, complete remission was more common in cTAK (87% vs 66%; P < 0.01), but subsequent relapses were equally common (30% vs 27%; P = 0.63). Independent associations of disease duration at presentation with disease extent [Disease Extent Index in TAK (DEI.Tak)] and damage [TAK Damage Score (TADS)] were observed (P ≤ 0.01). Moreover, 54% of patients with symptom duration of >5 years at presentation still continued to have elevated CRP suggesting continued and active inflammation warranting escalation or inititation of immunosuppression. CONCLUSION: Patients with cTAK are more likely to have arterial disease below the diaphragm, systemic inflammation and achieve remission. Disease of the aortic arch is more common in patients with aTAK. Longer duration of symptoms prior to initiation of immunosuppression, thereby leading to extensive disease and damage, reflects ongoing disease activity as the rule rather than exception in untreated TAK.


Assuntos
Aorta Torácica/patologia , Arterite de Takayasu/patologia , Adolescente , Adulto , Fatores Etários , Angiografia , Aorta Torácica/diagnóstico por imagem , Progressão da Doença , Feminino , Humanos , Índia , Masculino , Fatores Sexuais , Arterite de Takayasu/diagnóstico por imagem , Adulto Jovem
18.
Catheter Cardiovasc Interv ; 97(5): 815-824, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32294309

RESUMO

OBJECTIVES: To study the safety of stent avoidance, frequency of change in management decisions, and its cost implications while using a fractional flow reserve (FFR)-guided treatment strategy for intermediate-grade coronary artery stenosis. BACKGROUND: The impact of FFR in guiding management decisions and its cost implications has not been studied after imposition of a ceiling on stent prices by the Government of India. METHODS: In 400 patients with 477 intermediate-grade coronary lesions for whom coronary intervention was planned, functional assessment using FFR was done. Incidence of the primary composite endpoint (major adverse cardiac event [MACE], cardiac death, myocardial infarction, objective evidence of ischemia, and target vessel revascularization) in the stent avoided subset was compared with the stented group at follow-up. Micro-costing analysis was done using a computed model with current stent and FFR wire prices. RESULTS: The overall incidence of MACE was 4.9%, 0.9% in the stent-avoided subset and 6.9% in stented group (p = 0.04, comparing the latter two) at a median follow-up of 21 months (interquartile range 12-31 months). Serious adverse events occurred only in 1% of patients receiving adenosine. The average cost saving was Indian rupees (INR) 51,847 [United States Dollar (USD) 746] per patient, resulting in total savings of INR 15,813,379 (USD 227,530). Cost savings persisted but were lower by 36% (INR 18,613/USD 268 per patient) after the ceiling of stent prices. CONCLUSION: FFR-guided percutaneous coronary intervention (PCI) strategy is safe and cost-effective in countries where majority of patients self-finance their health care, resulting in stent and PCI avoidance in approximately one in three patients referred for coronary angioplasty.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Intervenção Coronária Percutânea , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/terapia , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Resultado do Tratamento
19.
Vascular ; 29(2): 163-170, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32807029

RESUMO

OBJECTIVE: To report a technique of creating mini-cuff-augmented fenestrations in endografts for use in endovascular aneurysm repair. METHODS: Circular fenestrations are made in Dacron thoracic (Valiant Captivia, Medtronic) or tapered iliac limb (Endurant, Medtronic) endografts using thermal cautery and the edges are strengthened with radio-opaque wire sutured on with 6-0 polypropylene. Straight thin-wall expanded polytetrafluoroethylene vascular graft of the same diameter as the fenestration is affixed to its edge with nonlocking 5-0 polypropylene suture, everted, trimmed, balloon-dilated to its nominal diameter and prevented from invaginating by relaxed external stay sutures. Mini-cuff-augmented fenestrations are often pre-cannulated with looped or externalized nitinol guidewires to facilitate catheter crossing. Successful use of mini-cuff-augmented fenestrations is illustrated in a symptomatic patient with Crawford extent-3 thoracoabdominal aortic and bilateral common iliac artery aneurysm undergoing endovascular repair. Seven mini-cuff-augmented fenestrations were created to preserve flow into five visceral arteries (celiac, superior mesenteric, left and dual right renal; all arising from the aneurysm) and both internal iliac arteries (arising at the aneurysm edge). RESULTS: Effective sealing was achieved immediately at all mini-cuff-augmented fenestrations. At 6-month follow-up there were no endoleaks, all fenestration stents were patent and undistorted, and the aneurysm sac size had decreased. CONCLUSION: Mini-cuff-augmented fenestrations accomplish effective fenestration sealing, despite being in aneurysmal zones, while preserving the advantages of fenestrations over cuffed branches.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Aneurisma Ilíaco/cirurgia , Stents , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/fisiopatologia , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Humanos , Aneurisma Ilíaco/diagnóstico por imagem , Aneurisma Ilíaco/fisiopatologia , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
20.
Rheumatology (Oxford) ; 59(5): 1118-1127, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31580452

RESUMO

OBJECTIVES: To develop and replicate, using data-driven methods, a novel classification system in Takayasu's arteritis based on distribution of arterial lesions. METHODS: Patients were included from four international cohorts at major academic centres: India (Christian Medical College Vellore); North America (National Institutes of Health, Vasculitis Clinical Research Consortium and Cleveland Clinic Foundation). All patients underwent whole-body angiography of the aorta and branch vessels, with categorization of arterial damage (stenosis, occlusion or aneurysm) in 13 territories. K-means cluster analysis was performed to identify subgroups of patients based on pattern of angiographic involvement. Cluster groups were identified in the Indian cohort and independently replicated in the North American cohorts. RESULTS: A total of 806 patients with Takayasu's arteritis from India (n = 581) and North America (n = 225) were included. Three distinct clusters defined by arterial damage were identified in the Indian cohort and replicated in each of the North American cohorts. Patients in cluster one had significantly more disease in the abdominal aorta, renal and mesenteric arteries (P < 0.01). Patients in cluster two had significantly more bilateral disease in the carotid and subclavian arteries (P < 0.01). Compared with clusters one and two, patients in cluster three had asymmetric disease with fewer involved territories (P < 0.01). Demographics, clinical symptoms and clinical outcomes differed by cluster. CONCLUSION: This large study in Takayasu's arteritis identified and replicated three novel subsets of patients based on patterns of arterial damage. Angiographic-based disease classification requires validation by demonstrating potential aetiological or prognostic implications.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Arterite de Takayasu/classificação , Arterite de Takayasu/diagnóstico por imagem , Centros Médicos Acadêmicos , Adulto , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/patologia , Análise por Conglomerados , Feminino , Humanos , Incidência , Índia/epidemiologia , Internacionalidade , Masculino , Artérias Mesentéricas/diagnóstico por imagem , Artérias Mesentéricas/patologia , Pessoa de Meia-Idade , América do Norte/epidemiologia , Reprodutibilidade dos Testes , Medição de Risco , Índice de Gravidade de Doença , Artéria Subclávia/diagnóstico por imagem , Artéria Subclávia/patologia , Arterite de Takayasu/epidemiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA