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3.
Small Methods ; : e2301610, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693080

RESUMO

Single impurities in insulators are now often used for quantum sensors and single photon sources, while nanoscale semiconductor doping features are being constructed for electrical contacts in quantum technology devices, implying that new methods for sensitive, non-destructive imaging of single- or few-atom structures are needed. X-ray fluorescence (XRF) can provide nanoscale imaging with chemical specificity, and features comprising as few as 100 000 atoms have been detected without any need for specialized or destructive sample preparation. Presently, the ultimate limits of sensitivity of XRF are unknown - here, gallium dopants in silicon are investigated using a high brilliance, synchrotron source collimated to a small spot. It is demonstrated that with a single-pixel integration time of 1 s, the sensitivity is sufficient to identify a single isolated feature of only 3000 Ga impurities (a mass of just 350 zg). With increased integration (25 s), 650 impurities can be detected. The results are quantified using a calibration sample consisting of precisely controlled numbers of implanted atoms in nanometer-sized structures. The results show that such features can now be mapped quantitatively when calibration samples are used, and suggest that, in the near future, planned upgrades to XRF facilities might achieve single-atom sensitivity.

4.
Funct Plant Biol ; 512024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38683936

RESUMO

Effective identification and usage of genetic variation are prerequisites for developing nutrient-efficient cultivars. A collection of 94 safflower (Carthamus tinctorius ) genotypes (G) was investigated for important morphological and photosynthetic traits at four nitrogen (N) treatments. We found significant variation for all the studied traits except chlorophyll b (chl b ) among safflower genotypes, nitrogen treatments and G×N interaction. The examined traits showed a 2.82-50.00% increase in response to N application. Biological yield (BY) reflected a significantly positive correlation with fresh shoot weight (FSW), root length (RL), fresh root weight (FRW) and number of leaves (NOL), while a significantly positive correlation was also observed among carotenoids (C), chlorophyll a (chl a ), chl b and total chlorophyll content (CT) under all treatments. Superior genotypes with respect to plant height (PH), FSW, NOL, RL, FRW and BY were clustered into Group 3, while genotypes with better mean performance regarding chl a , chl b C and CT were clustered into Group 2 as observed in principal component analysis. The identified eight best-performing genotypes could be useful to develop improved nitrogen efficient cultivars. Genome-wide association analysis resulted in 32 marker-trait associations (MTAs) under four treatments. Markers namely DArT-45481731 , DArT-17812864 , DArT-15670279 and DArT-45482737 were found consistent. Protein-protein interaction networks of loci associated with MTAs were related to fatty acid and branched-chain amino acid metabolism and histone modifications.


Assuntos
Aminoácidos de Cadeia Ramificada , Carthamus tinctorius , Ácidos Graxos , Estudo de Associação Genômica Ampla , Nitrogênio , Carthamus tinctorius/genética , Carthamus tinctorius/metabolismo , Carthamus tinctorius/efeitos dos fármacos , Nitrogênio/metabolismo , Ácidos Graxos/metabolismo , Aminoácidos de Cadeia Ramificada/metabolismo , Genótipo , Código das Histonas/efeitos dos fármacos , Clorofila/metabolismo , Loci Gênicos
5.
Commun Biol ; 7(1): 280, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38448784

RESUMO

X-ray computed tomography (XCT) and X-ray fluorescence (XRF) imaging are two non-invasive imaging techniques to study cellular structures and chemical element distributions, respectively. However, correlative X-ray computed tomography and fluorescence imaging for the same cell have yet to be routinely realized due to challenges in sample preparation and X-ray radiation damage. Here we report an integrated experimental and computational workflow for achieving correlative multi-modality X-ray imaging of a single cell. The method consists of the preparation of radiation-resistant single-cell samples using live-cell imaging-assisted chemical fixation and freeze-drying procedures, targeting and labeling cells for correlative XCT and XRF measurement, and computational reconstruction of the correlative and multi-modality images. With XCT, cellular structures including the overall structure and intracellular organelles are visualized, while XRF imaging reveals the distribution of multiple chemical elements within the same cell. Our correlative method demonstrates the feasibility and broad applicability of using X-rays to understand cellular structures and the roles of chemical elements and related proteins in signaling and other biological processes.


Assuntos
Pesquisa , Tomografia Computadorizada por Raios X , Raios X , Radiografia , Imagem Óptica
6.
Minerva Anestesiol ; 90(4): 321-329, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38498317

RESUMO

INTRODUCTION: The aim of this systemic review and meta-analysis was to assess the impact of prophylactic use of esketamine on postoperative depression and quality of life in patients. EVIDENCE ACQUISITION: We searched for all articles on esketamine in patients after surgury in electronic data bases, including PubMed, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science, up to the June 2023.The included studies compared the impact of using esketamine and placebo on postoperative depression and quality of life in patients through randomized controlled trials. The outcome measurements consist of postoperative depression and indicators that can reflect the impact on patients' post Cochrane Risk of Bias tool in Review Manager 5.4 tool was adopted to assess the risk of bias. EVIDENCE SYNTHESIS: The study included a total of 11 randomized controlled trials with 1447 participants. This meta-analysis demonstrated that the prophylactic use of esketamine alleviated postoperative depressive symptoms (standardized mean difference [SMD]: -0.61; 95% confidence interval [CI]: -0.96 to -0.25; P=0.0008) and incidence (relative risk [RR]:0.37;95% [CI]: 0.22 to 0.62; P=0.0001), reducing the occurrence of postoperative depression, anxiety, and chronic pain. Additionally, it improved postoperative sleep quality and enhanced the postoperative quality of life for patients. CONCLUSIONS: Prophylactic use of esketamine during the preoperative and anesthesia period has shown significant benefits in improving postoperative quality of life. It can effectively alleviate postoperative depression, anxiety, and chronic pain, as well as enhance sleep quality.


Assuntos
Depressão , Ketamina , Complicações Pós-Operatórias , Qualidade de Vida , Ketamina/uso terapêutico , Humanos , Depressão/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Nanoscale ; 16(11): 5760-5767, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38412012

RESUMO

Magnetic nanomaterials are sought to provide new functionalities for applications ranging from information processing and storage to energy generation and biomedical imaging. MXenes are a rapidly growing family of two-dimensional transition metal carbides and nitrides with versatile chemical and structural diversity, resulting in a variety of interesting electronic and optical properties. However, strategies for producing MXenes with tailored magnetic responses remain underdeveloped and challenging. Herein, we incorporate elemental Ni and Co into Ti3C2Tx MXene by mixing with dilute metal chloride solutions. We achieve a uniform distribution of Ni and Co, confirmed by X-ray fluorescence (XRF) mapping with nanometer resolution, with Ni and Co concentrations of approximately 2 and 7 at% relative to the Ti concentration. The magnetic susceptibility of these Ni- and Co-incorporated Ti3C2Tx MXenes is one to two orders of magnitude larger than pristine Ti3C2Tx, illustrating the potential for dilute metal incorporation to enhance linear magnetic responses at room temperature.

9.
AJR Am J Roentgenol ; 222(3): e2329778, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37991334

RESUMO

BACKGROUND. The higher spatial resolution and image contrast for iodine-containing tissues of photon-counting detector (PCD) CT may address challenges in evaluating small calcified vessels when performing lower extremity CTA by energy-integrating detector (EID) CTA. OBJECTIVE. The purpose of the study was to compare the evaluation of infrapopliteal vasculature between lower extremity CTA performed using EID CT and PCD CT. METHODS. This prospective study included 32 patients (mean age, 69.7 ± 11.3 [SD] years; 27 men, five women) who underwent clinically indicated lower extremity EID CTA between April 2021 and March 2022; participants underwent investigational lower extremity PCD CTA later the same day as EID CTA using a reduced IV contrast media dose. Two radiologists independently reviewed examinations in two sessions, each containing a random combination of EID CTA and PCD CTA examinations; the readers assessed the number of visualized fibular perforators, characteristics of stenoses at 11 infrapopliteal segmental levels, and subjective arterial sharpness. RESULTS. Mean IV contrast media dose was 60.0 ± 11.0 (SD) mL for PCD CTA versus 139.6 ± 11.8 mL for EID CTA (p < .001). The number of identified fibular perforators per lower extremity was significantly higher for PCD CTA than for EID CTA for reader 1 (R1) (mean ± SD, 6.4 ± 3.2 vs 4.2 ± 2.4; p < .001) and reader 2 (R2) (8.8 ± 3.4 vs 7.6 ± 3.3; p = .04). Reader confidence for assessing stenosis was significantly higher for PCD CTA than for EID CTA for R1 (mean ± SD, 82.3 ± 20.3 vs 78.0 ± 20.2; p < .001) but not R2 (89.8 ± 16.7 vs 90.6 ± 7.1; p = .24). The number of segments per lower extremity with total occlusion was significantly lower for PCD CTA than for EID CTA for R2 (mean ± SD, 0.5 ± 1.3 vs 0.9 ± 1.7; p = .04) but not R1 (0.6 ± 1.3 vs 1.0 ± 1.5; p = .07). The number of segments per lower extremity with clinically significant nonocclusive stenosis was significantly higher for PCD CTA than for EID CTA for R1 (mean ± SD, 2.2 ± 2.2 vs 1.6 ± 1.7; p = .01) but not R2 (1.1 ± 2.0 vs 1.1 ± 1.4; p = .89). Arterial sharpness was significantly greater for PCD CTA than for EID CTA for R1 (mean ± SD, 3.2 ± 0.5 vs 1.8 ± 0.5; p < .001) and R2 (3.2 ± 0.4 vs 1.7 ± 0.8; p < .001). CONCLUSION. PCD CTA yielded multiple advantages relative to EID CTA for visualizing small infrapopliteal vessels and characterizing associated plaque. CLINICAL IMPACT. The use of PCD CTA may improve vascular evaluation in patients with peripheral arterial disease.


Assuntos
Meios de Contraste , Fótons , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Prospectivos , Constrição Patológica , Imagens de Fantasmas , Tomografia Computadorizada por Raios X/métodos , Extremidade Inferior/diagnóstico por imagem
10.
Trop Biomed ; 40(3): 370-374, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37897172

RESUMO

Beetles (Coleoptera) are known to constitute forensic evidence in medico-legal investigations as their presence can be used to date human remains in almost all decomposition stages. Many forensic studies focus on the successional colonization pattern of flies (Diptera); however, beetles have not so far been studied extensively for this aspect. A beetle of the genus Afromorgus Scholtz, 1986, A. chinensis (Boheman, 1858) (Scarabaeoidea: Trogidae), was found beneath a late decaying rabbit carcass at Paya Indah Wetland, Dengkil, Malaysia, for the first time. Both genus and species are already known to occur in Malaysia from literature.


Assuntos
Besouros , Dípteros , Entomologia Forense , Animais , Coelhos , Humanos , Mudanças Depois da Morte , Ciências Forenses , Entomologia , Cadáver , Comportamento Alimentar
11.
J Oral Sci ; 65(4): 237-242, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37612067

RESUMO

PURPOSE: This study was conducted to investigate the dental and palatal arch dimensions of male and female siblings in relation to gender and age, using three-dimensional (3D) digital casts. METHODS: This study involved 54 subjects (27 pairs) of male-female siblings aged 15 to 45 years. Dental casts were digitized and analyzed for tooth size (TS), arch width (AW), arch length (AL), arch length discrepancy (ALD), and palatal arch dimensions (PAD). The data obtained were subjected to t-tests, and the palatal curvature (PC) was modeled using a fourth-order polynomial. RESULTS: Significant differences (P < 0.05) between the sexes were found in the mesiodistal TS, particularly in all canines, as well as 16, 36, 46, and 41. Maxillary AW and AL were also significantly (P < 0.05) influenced by sexes. Most arch parameters were more prominent in male siblings, and the effect of age on PC differed between the sexes. In addition, the PC of adolescent females was mostly superimposed on adult females relative to males. CONCLUSION: Among siblings, males were found to have significantly larger dental arch dimensions than females. Furthermore, PC showed some differences between the sexes in both the frontal and sagittal planes.

12.
Sci Adv ; 9(32): eadg8869, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37566654

RESUMO

Dopamine is broadly implicated in reinforcement learning, but how patterns of dopamine activity are generated is poorly resolved. Here, we demonstrate that two ion channels, Kv4.3 and BKCa1.1, regulate the pattern of dopamine neuron firing and dopamine release on different time scales to influence separate phases of reinforced behavior in mice. Inactivation of Kv4.3 in VTA dopamine neurons increases ex vivo pacemaker activity and excitability that is associated with increased in vivo firing rate and ramping dynamics before lever press in a learned instrumental paradigm. Loss of Kv4.3 enhances performance of the learned response and facilitates extinction. In contrast, loss of BKCa1.1 increases burst firing and phasic dopamine release that enhances learning of an instrumental response and enhances extinction burst lever pressing in early extinction that is associated with a greater change in activity between reinforced and unreinforced actions. These data demonstrate that disruption of intrinsic regulators of neuronal activity differentially affects dopamine dynamics during reinforcement and extinction learning.


Assuntos
Dopamina , Neurônios Dopaminérgicos , Camundongos , Animais , Reforço Psicológico , Aprendizagem , Canais Iônicos
13.
J Med Chem ; 66(14): 9401-9417, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37439511

RESUMO

We report the discovery of sulanemadlin (ALRN-6924), the first cell-permeating, stabilized α-helical peptide to enter clinical trials. ALRN-6924 is a "stapled peptide" that mimics the N-terminal domain of the p53 tumor suppressor protein. It binds with high affinity to both MDM2 and MDMX (also known as MDM4), the endogenous inhibitors of p53, to activate p53 signaling in cells having a non-mutant, or wild-type TP53 genotype (TP53-WT). Iterative structure-activity optimization endowed ALRN-6924 with favorable cell permeability, solubility, and pharmacokinetic and safety profiles. Intracellular proteolysis of ALRN-6924 forms a long-acting active metabolite with potent MDM2 and MDMX binding affinity and slow dissociation kinetics. At high doses, ALRN-6924 exhibits on-mechanism anticancer activity in TP53-WT tumor models. At lower doses, ALRN-6924 transiently arrests the cell cycle in healthy tissues to protect them from chemotherapy without protecting the TP53-mutant cancer cells. These results support the continued clinical evaluation of ALRN-6924 as an anticancer and chemoprotection agent.


Assuntos
Antineoplásicos , Proteína Supressora de Tumor p53 , Proteína Supressora de Tumor p53/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Ligação Proteica , Peptídeos/química , Antineoplásicos/química , Proteínas de Ciclo Celular/metabolismo
14.
Environ Sci Nano ; 10(7): 1768-1777, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37457049

RESUMO

Coal combustion byproducts are known to be enriched in arsenic (As) and selenium (Se). This enrichment is a concern during the handling, disposal, and reuse of the ash as both elements can be harmful to wildlife and humans if mobilized into water and soils. The leaching potential and bioaccessibility of As and Se in coal fly ash depends on the chemical forms of these elements and their association with the large variety of particles that comprise coal fly ash. The overall goal of this research was to determine nanoscale and microscale solid phase mineral associations and oxidation states of As and Se in fly ash. We utilized nanoscale 2D imaging (30-50 nm spot size) with the Hard X-ray Nanoprobe (HXN) in combination with microprobe X-ray capabilities (∼5 µm resolution) to determine the As and Se elemental associations. Speciation of As and Se was also measured at the nano- to microscale with X-ray absorption spectroscopy. The enhanced resolution of HXN showed As and Se as either diffusely located around or comingled with Ca- and Fe-rich particles. The results also showed nanoparticles of Se attached to the surface of fly ash grains. Overall, a comparison of As and Se species across scales highlights the heterogeneity and complexity of chemical associations for these trace elements of concern in coal fly ash.

15.
Antimicrob Agents Chemother ; 67(7): e0048123, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37338374

RESUMO

Administration of tuberculosis preventive therapy (TPT) to individuals with latent tuberculosis infection is an important facet of global tuberculosis control. The use of long-acting injectable (LAI) drug formulations may simplify and shorten regimens for this indication. Rifapentine and rifabutin have antituberculosis activity and physiochemical properties suitable for LAI formulation, but there are limited data available for determining the target exposure profiles required for efficacy in TPT regimens. The objective of this study was to determine exposure-activity profiles of rifapentine and rifabutin to inform development of LAI formulations for TPT. We used a validated paucibacillary mouse model of TPT in combination with dynamic oral dosing of both drugs to simulate and understand exposure-activity relationships to inform posology for future LAI formulations. This work identified several LAI-like exposure profiles of rifapentine and rifabutin that, if achieved by LAI formulations, could be efficacious as TPT regimens and thus can serve as experimentally determined targets for novel LAI formulations of these drugs. We present novel methodology to understand the exposure-response relationship and inform the value proposition for investment in development of LAI formulations that have utility beyond latent tuberculosis infection.


Assuntos
Tuberculose Latente , Rifabutina , Animais , Camundongos , Rifabutina/uso terapêutico , Antituberculosos/uso terapêutico , Tuberculose Latente/tratamento farmacológico , Tuberculose Latente/prevenção & controle , Rifampina/uso terapêutico
16.
Sci Rep ; 13(1): 7271, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37142634

RESUMO

X-ray fluorescence mapping (XRF) is a highly efficient and non-invasive technique for quantifying material composition with micro and nanoscale spatial resolutions. Quantitative XRF analysis, however, confronts challenges from the long-lasting problem called self-absorption. Moreover, correcting two-dimensional XRF mapping datasets is particularly difficult because it is an ill-posed inverse problem. Here we report a semi-empirical method that can effectively correct 2D XRF mapping data. The correction error is generally less than 10% from a comprehensive evaluation of the accuracy in various configurations. The proposed method was applied to quantify the composition distribution around the grain boundaries in an electrochemically corroded stainless steel sample. Highly localized Cr enrichment was found around the crack sites, which was invisible before the absorption correction.

17.
bioRxiv ; 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37090528

RESUMO

Administration of tuberculosis preventive therapy (TPT) to individuals with latent tuberculosis infection is an important facet of global tuberculosis control. The use of long-acting injectable (LAI) drug formulations may simplify and shorten regimens for this indication. Rifapentine and rifabutin have anti-tuberculosis activity and physiochemical properties suitable for LAI formulation, but there are limited data available for determining the target exposure profiles required for efficacy in TPT regimens. The objective of this study was to determine exposure-activity profiles of rifapentine and rifabutin to inform development of LAI formulations for TPT. We utilized a validated paucibacillary mouse model of TPT in combination with dynamic oral dosing of both drugs to simulate and understand exposure-activity relationships to inform posology for future LAI formulations. This work identified several LAI-like exposure profiles of rifapentine and rifabutin that, if achieved by LAI formulations, could be efficacious as TPT regimens and thus can serve as experimentally-determined targets for novel LAI formulations of these drugs. We present novel methodology to understand the exposure-response relationship and inform the value proposition for investment in development of LAI formulations that has utility beyond latent tuberculosis infection.

18.
Histopathology ; 83(2): 168-177, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36849852

RESUMO

AIMS: The prognostic role of EGFR mutations remains controversial. We aimed to evaluate the prognostic role of EGFR mutation in consideration of the IASLC histological grade in patients with resected early-stage lung adenocarcinoma. METHODS AND RESULTS: A total of 3297 patients with stages I-IIA resected lung adenocarcinoma who had had EGFR mutation tests between January 2014 and December 2019 at the Samsung Medical Center, Seoul, Korea were included. Recurrence-free survival (RFS) was compared by EGFR mutation status (EGFR-M+ versus EGFR-WT) and IASLC histological grade (G1, G2 and G3). Cox proportional hazards models were used to estimate the adjusted HRs (aHRs) and 95% confidence intervals (CIs). RESULTS: Compared to the EGFR-WT group, the EGFR-M+ group had a significantly lower proportion of G3 tumour (16 versus 33%, P < 0.001). During a median follow-up of 41.4 months, 376 patients experienced recurrence. After adjusting for histological grade, the aHR for recurrence comparing the EGFR-M+ to the EGFR-WT was 1.30 (95% CI = 1.04-1.62, P = 0.022). The EGFR-M+ group had a significantly lower 5-year RFS than the EGFR-WT group among G3 patients (58.4 versus 71.5%, P < 0.001), but not among G1 and G2 patients. CONCLUSIONS: EGFR mutation status was associated with a risk of recurrence after consideration of the IASLC histological grading, especially in G3 tumours. The results of this study would be useful for developing a new staging system and identifying a subset of patients who may benefit from adjuvant targeted therapy.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Humanos , Prognóstico , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Receptores ErbB/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma/genética , Adenocarcinoma/cirurgia , Mutação , Estudos Retrospectivos
19.
AJR Am J Roentgenol ; 220(1): 73-85, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35731096

RESUMO

BACKGROUND. Anatomic redundancy between phases can be used to achieve denoising of multiphase CT examinations. A limitation of iterative reconstruction (IR) techniques is that they generally require use of CT projection data. A frequency-split multi-band-filtration algorithm applies denoising to the multiphase CT images themselves. This method does not require knowledge of the acquisition process or integration into the reconstruction system of the scanner, and it can be implemented as a supplement to commercially available IR algorithms. OBJECTIVE. The purpose of the present study is to compare radiologists' performance for low-contrast and high-contrast diagnostic tasks (i.e., tasks for which differences in CT attenuation between the imaging target and its anatomic background are subtle or large, respectively) evaluated on multiphase abdominal CT between routine-dose images and radiation dose-reduced images processed by a frequency-split multiband-filtration denoising algorithm. METHODS. This retrospective single-center study included 47 patients who underwent multiphase contrast-enhanced CT for known or suspected liver metastases (a low-contrast task) and 45 patients who underwent multiphase contrast-enhanced CT for pancreatic cancer staging (a high-contrast task). Radiation dose-reduced images corresponding to dose reduction of 50% or more were created using a validated noise insertion technique and then underwent denoising using the frequency-split multi-band-filtration algorithm. Images were independently evaluated in multiple sessions by different groups of abdominal radiologists for each task (three readers in the low-contrast arm and four readers in the high-contrast arm). The noninferiority of denoised radiation dose-reduced images to routine-dose images was assessed using the jackknife alternative free-response ROC (JAFROC) figure-of-merit (FOM; limit of noninferiority, -0.10) for liver metastases detection and using the Cohen kappa statistic and reader confidence scores (100-point scale) for pancreatic cancer vascular invasion. RESULTS. For liver metastases detection, the JAFROC FOM for denoised radiation dose-reduced images was 0.644 (95% CI, 0.510-0.778), and that for routine-dose images was 0.668 (95% CI, 0.543-0.792; estimated difference, -0.024 [95% CI, -0.084 to 0.037]). Intraobserver agreement for pancreatic cancer vascular invasion was substantial to near perfect when the two image sets were compared (κ = 0.53-1.00); the 95% CIs of all differences in confidence scores between image sets contained zero. CONCLUSION. Multiphase contrast-enhanced abdominal CT images with a radiation dose reduction of 50% or greater that undergo denoising by a frequency-split multiband-filtration algorithm yield performance similar to that of routine-dose images for detection of liver metastases and vascular staging of pancreatic cancer. CLINICAL IMPACT. The image-based denoising algorithm facilitates radiation dose reduction of multiphase examinations for both low- and high-contrast diagnostic tasks without requiring manufacturer-specific hardware or software.


Assuntos
Neoplasias Hepáticas , Tomografia Computadorizada por Raios X , Humanos , Estudos Retrospectivos , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Algoritmos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos
20.
Dis Colon Rectum ; 66(2): 243-252, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36538706

RESUMO

BACKGROUND: Refractory perianal Crohn's disease remains notoriously difficult to treat. We developed a novel technology using a commercially available bioabsorbable fistula plug to deliver autologous adipose-derived mesenchymal stem cells. OBJECTIVE: This study aimed to assess therapeutic safety and feasibility in the completed STOMP (stem cells on matrix plugs) phase 1 clinical trial. DESIGN: Prospective single-arm phase I clinical trial. SETTING: Tertiary academic medical center. PATIENTS: Adults (aged 18-65 y) with complex single-tract Crohn's disease perianal fistula who have failed conventional therapy were included in this study. INTERVENTION: Autologous adipose-derived mesenchymal stem cells were isolated, ex vivo culture expanded, and seeded onto a commercially available bioabsorbable fistula plug. Six weeks later, patients returned to the operating room for removal of the seton and placement of the stem cell-loaded plug. MAIN OUTCOME MEASURES: Patients were followed up for a total of 8 visits through 12 months. Safety was the primary end point; clinical healing and MRI response were secondary end points. RESULTS: Twenty patients (12 females; mean age 36 y) were treated with the stem cell-loaded plug. Of the 20 patients enrolled, 3 were not included in the 12-month analysis because of study withdrawal. Through 12 months, no patient experienced a serious adverse event related to the stem cell-loaded plug. Four patients experienced 7 serious adverse events and 12 patients experienced 22 adverse events. Complete clinical healing occurred in 14 of 18 patients at 6 months and 13 of 17 patients at 12 months. MRI response was observed in 12 of 18 patients at 6 months. LIMITATIONS: The main limitations were the small sample size and restrictive inclusion criteria. CONCLUSIONS: A stem cell-loaded plug can safely and effectively deliver cell-based therapy for patients with single-tract fistulizing perianal Crohn's disease. See Video Abstract at http://links.lww.com/DCR/C70 . RESPUESTA DURADERA OBSERVADA EN PACIENTES CON ENFERMEDAD DE CROHN PERIANAL FISTULIZANTE REFRACTARIA MEDIANTE EL USO DE CLULAS MADRE MESENQUIMALES AUTLOGAS EN UNA MATRIZ DISOLUBLE RESULTADOS DEL ENSAYO DE FASE I STEM CELL ON MATRIX PLUG: ANTECEDENTES:La enfermedad de Crohn perianal refractaria sigue siendo notoriamente difícil de tratar. Desarrollamos una tecnología novedosa utilizando un tapón de fístula bioabsorbible disponible comercialmente para administrar células madre mesenquimales derivadas de tejido adiposo autólogo.OBJETIVO:Evaluar la seguridad y viabilidad terapéutica en el ensayo finalizado STOMP.DISEÑO:Ensayo clínico prospectivo de fase I de un solo brazo.AJUSTE:Centro médico académico terciario.PACIENTES:Adultos (18-65) con fístula perianal compleja de la enfermedad de Crohn de un solo tracto que han fracasado con la terapia convencional.INTERVENCIÓN:Se aislaron células madre mesenquimales derivadas de tejido adiposo autólogo, se expandieron en cultivo ex vivo y se sembraron en un tapón de fístula bioabsorbible disponible comercialmente. Seis semanas después, los pacientes regresaron al quirófano para retirar el setón y colocar el tapón cargado de células madre.PRINCIPALES MEDIDAS DE RESULTADO:Los pacientes fueron seguidos durante un total de 8 visitas durante 12 meses. La seguridad fue el criterio principal de valoración; la curación clínica y la respuesta a la resonancia magnética fueron criterios de valoración secundarios.RESULTADOS:Veinte pacientes (12 mujeres, edad media 36 años) fueron tratados con el tapón cargado de células madre. De los 20 pacientes inscritos, tres no se incluyeron en el análisis de 12 meses porque se retiraron del estudio. A lo largo de 12 meses, ningún paciente experimentó un evento adverso grave relacionado con el tapón cargado de células madre. Cuatro pacientes experimentaron 7 eventos adversos graves y 12 pacientes experimentaron 22 eventos adversos. La curación clínica completa ocurrió en 14 de 18 pacientes a los 6 meses y en 13 de 17 pacientes a los 12 meses. La respuesta a la resonancia magnética se observó en 12 de 18 pacientes a los 6 meses.LIMITACIONES:Las principales limitaciones son el tamaño pequeño de la muestra y los criterios de inclusión restrictivos.CONCLUSIONES:Un tapón cargado de células madre se puede administrar de manera segura y efectiva, una terapia basada en células para pacientes con enfermedad de Crohn perianal fistulizante de un solo tracto. Consule Video Resumen en http://links.lww.com/DCR/C70 . (Traducción- Dr. Yesenia Rojas-Khalil ).


Assuntos
Doença de Crohn , Células-Tronco Mesenquimais , Fístula Retal , Adulto , Feminino , Humanos , Doença de Crohn/complicações , Doença de Crohn/terapia , Estudos Prospectivos , Fístula Retal/etiologia , Fístula Retal/terapia , Estudos Retrospectivos , Células-Tronco
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