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1.
Magn Reson Med ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39219299

RESUMO

PURPOSE: Ultrashort echo time (UTE) MRI can be a radiation-free alternative to CT for craniofacial imaging of pediatric patients. However, unlike CT, bone-specific MR imaging is limited by long scan times, relatively low spatial resolution, and a time-consuming bone segmentation workflow. METHODS: A rapid, high-resolution UTE technique for brain and skull imaging in conjunction with an automatic segmentation pipeline was developed. A dual-RF, dual-echo UTE sequence was optimized for rapid scan time (3 min) and smaller voxel size (0.65 mm3). A weighted least-squares conjugate gradient method for computing the bone-selective image improves bone specificity while retaining bone sensitivity. Additionally, a deep-learning U-Net model was trained to automatically segment the skull from the bone-selective images. Ten healthy adult volunteers (six male, age 31.5 ± 10 years) and three pediatric patients (two male, ages 12 to 15 years) were scanned at 3 T. Clinical CT for the three patients were obtained for validation. Similarities in 3D skull reconstructions relative to clinical standard CT were evaluated based on the Dice similarity coefficient and Hausdorff distance. Craniometric measurements were used to assess geometric accuracy of the 3D skull renderings. RESULTS: The weighted least-squares method produces images with enhanced bone specificity, suppression of soft tissue, and separation from air at the sinuses when validated against CT in pediatric patients. Dice similarity coefficient overlap was 0.86 ± 0.05, and the 95th percentile Hausdorff distance was 1.77 ± 0.49 mm between the full-skull binary masks of the optimized UTE and CT in the testing dataset. CONCLUSION: An optimized MRI acquisition, reconstruction, and segmentation workflow for craniofacial imaging was developed.

2.
BMC Neurol ; 24(1): 329, 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39244562

RESUMO

BACKGROUND: Early neurological deterioration (END) occurs in many patients with acute ischemic stroke due to a variety of causes. Although pharmacologically induced hypertension (PIH) and anticoagulants have been investigated in several clinical trials for the treatment of END, the efficacy and safety of these treatments remain unclear. Here, we investigated whether PIH or anticoagulation is better as a rescue therapy for the progression of END in patients with lacunar stroke. METHODS: This study included patients with lacunar stroke who received rescue therapy with END within 3 days of symptom onset between April 2014 and August 2021. In the PIH group, phenylephrine was administered intravenously for 24 h and slowly tapered when symptoms improved or after 5 days of PIH. In the anticoagulation group, argatroban was administered continuously intravenously for 2 days and twice daily for next 5 days. We compared END recovery, defined as improvement in NIHSS from baseline, excellent outcomes (0 or 1 mRS at 3 months), and safety profile. RESULTS: Among the 4818 patients with the lacunar stroke, END occurred in 147 patients. Seventy-nine patients with END received PIH (46.9%) and 68 patients (46.3%) received anticoagulation therapy. There was no significant difference in age (P = 0.82) and sex (P = 0.87) between the two groups. Compared to the anticoagulation group, the PIH group had a higher incidence of END recovery (77.2% vs. 51.5%, P < 0.01) and excellent outcomes (34.2% vs. 16.2%, P = 0.04). PIH was associated with END (HR 2.49; 95% CI 1.06-5.81, P = 0.04). PIH remained associated with END recovery (adjusted HR 3.91; 95% CI 1.19-12.90, P = 0.02). Safety outcomes, like hemorrhagic conversion and mortality, were not significantly different between the two groups. CONCLUSIONS: As a rescue therapy for the progression of END in lacunar stroke patients, PIH with phenylephrine was more effective with similar safety compared to anticoagulation with argatroban.


Assuntos
Anticoagulantes , Acidente Vascular Cerebral Lacunar , Humanos , Masculino , Feminino , Acidente Vascular Cerebral Lacunar/tratamento farmacológico , Idoso , Pessoa de Meia-Idade , Anticoagulantes/uso terapêutico , Anticoagulantes/administração & dosagem , Hipertensão/tratamento farmacológico , Hipertensão/complicações , Idoso de 80 Anos ou mais , Sulfonamidas/uso terapêutico , Sulfonamidas/administração & dosagem , Arginina/análogos & derivados , Arginina/uso terapêutico , Arginina/administração & dosagem , Resultado do Tratamento , Anti-Hipertensivos/uso terapêutico , Anti-Hipertensivos/administração & dosagem , Estudos Retrospectivos , Progressão da Doença , Ácidos Pipecólicos
3.
Nucl Med Mol Imaging ; 58(5): 258-278, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39036459

RESUMO

The majority of solid tumors have hypoxia, or low oxygen levels, which is one of the hallmarks of cancer. Hypoxia was found to relate to cancer metastases and resistance to therapies, therefore, detection of hypoxia plays an important role in the process of cancer prognosis and treatment. Single-photon emission computed tomography (SPECT) is a non-invasive imaging technique using gamma-emitting radiopharmaceuticals to visualize biological activities within the body. SPECT is also applied for the detection of tumor hypoxia with the development of hypoxia-targeting radiopharmaceuticals. Radiopharmaceuticals containing nitroimidazole moieties have received increasing attention due to their bio-reducible characteristics which make the radiopharmaceuticals accumulate in the hypoxia regions. This review summarizes the recent development of 99mTc-labeled radiopharmaceuticals bearing nitroimidazoles for SPECT imaging of tumor hypoxia including the synthetic methods and results of animal studies.

4.
Front Neurol ; 15: 1375609, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38817546

RESUMO

Background: Lipid-lowering therapies are mainstays in reducing recurrence after acute ischemic stroke (AIS). Evolocumab, a Proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitor, is a promising lipid-lowering agent known to decrease LDL cholesterol and mitigate vascular events alongside statins. However, its effects on the early functional outcomes post-mechanical thrombectomy (MT) remain unclear. This study aimed to assess the short-term effects and incidence of bleeding events after the early, off-label use of PCSK9 inhibitors in AIS patients undergoing MT. Methods: We retrospectively analyzed patients who had MT at a Regional Stroke Center from December 2018 to April 2023. Our primary outcome was discharge functional outcomes. Secondary outcomes included early neurologic deterioration (END), symptomatic intracerebral hemorrhage (sICH), 3-month functional outcomes, 3-month recurrence rate, and lipid profiles. Results: Of 261 patients (mean age 69.2 ± 11.7, men 42.9%), 42 were administered evolocumab peri-procedurally. While baseline characteristics were similar between the two groups, evolocumab group demonstrated improved discharge outcomes, with a lower mean NIHSS (8.8 ± 6.8 vs. 12.4 ± 9.8, p = 0.02) and a higher percentage of patients with discharge mRS ≤ 3 (52.4% vs. 35.6%, p = 0.041). The 3-month follow-up show a non-significant trend toward an improved outcome in the evolocumab group. Multivariable analysis indicated that evolocumab had a potential impact on favorable discharge outcomes (aOR 1.98[0.94-4.22] for mRS ≤ 3 and 0.47[0.27-0.84] for lower ordinal mRS). Notably, evolocuamb users exhibited fewer instances of END and sICH, although they do not reach statistical significance. Additionally, the evolocumab group demonstrated potential benefits in LDL cholesterol reduction over time. Conclusion: Early use of evolocumab in AIS patients undergoing MT appeared to be safe and associated with better early functional outcomes. The potential benefit of the PCSK9 inhibitor shown here warrants further prospective studies.

5.
MAGMA ; 37(1): 83-92, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37934295

RESUMO

OBJECTIVES: CT is the clinical standard for surgical planning of craniofacial abnormalities in pediatric patients. This study evaluated three MRI cranial bone imaging techniques for their strengths and limitations as a radiation-free alternative to CT. METHODS: Ten healthy adults were scanned at 3 T with three MRI sequences: dual-radiofrequency and dual-echo ultrashort echo time sequence (DURANDE), zero echo time (ZTE), and gradient-echo (GRE). DURANDE bright-bone images were generated by exploiting bone signal intensity dependence on RF pulse duration and echo time, while ZTE bright-bone images were obtained via logarithmic inversion. Three skull segmentations were derived, and the overlap of the binary masks was quantified using dice similarity coefficient. Craniometric distances were measured, and their agreement was quantified. RESULTS: There was good overlap of the three masks and excellent agreement among craniometric distances. DURANDE and ZTE showed superior air-bone contrast (i.e., sinuses) and soft-tissue suppression compared to GRE. DISCUSSIONS: ZTE has low levels of acoustic noise, however, ZTE images had lower contrast near facial bones (e.g., zygomatic) and require effective bias-field correction to separate bone from air and soft-tissue. DURANDE utilizes a dual-echo subtraction post-processing approach to yield bone-specific images, but the sequence is not currently manufacturer-supported and requires scanner-specific gradient-delay corrections.


Assuntos
Processamento de Imagem Assistida por Computador , Crânio , Adulto , Humanos , Criança , Processamento de Imagem Assistida por Computador/métodos , Crânio/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
6.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-1044575

RESUMO

The use of cardiac implantable electronic devices (CIEDs) has increased significantly in recent years. Consequently, more patients with CIEDs will undergo surgery during their lifetime, and thus the involvement of anesthesiologists in the perioperative management of CIEDs is increasing. With ongoing advancements in technology, many types of CIEDs have been developed, including permanent pacemakers, leadless pacemakers, implantable cardioverter defibrillators, cardiac resynchronization therapy-pacemakers/defibrillators, and implantable loop recorders. The functioning of CIEDs exposed to an electromagnetic field can be affected by electromagnetic interference, potential sources of which can be found in the operating room. Thus, to prevent potential adverse events caused by electromagnetic interference in the operating room, anesthesiologists must have knowledge of CIEDs and be able to identify each type. This review focuses on the perioperative management of patients with CIEDs, including indications for CIED implantation to determine the baseline cardiovascular status of patients; concerns associated with CIEDs before and during surgery; perioperative management of CIEDs, including magnet application and device reprogramming; and additional perioperative provisions for patients with CIEDs. As issues such as variations in programming capabilities and responses to magnet application according to device can be challenging, this review provides essential information for the safe perioperative management of patients with CIEDs.

7.
Org Biomol Chem ; 21(42): 8494-8499, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37861427

RESUMO

A facile one-pot transformation of benzyl esters into esters, amides, and anhydrides is described. α,α-Dichlorodiphenylmethane and FeCl3 were employed as the chlorinating agent and catalyst respectively to convert benzyl esters into acid chloride intermediates, which directly reacted with alcohols, amines, and carboxylic acids. Various esters, amides, and anhydrides were readily obtained with high yields under mild conditions. This method is promising for the practical synthesis of esters, amides, and anhydrides from benzyl esters.

8.
RSC Adv ; 13(45): 31346-31352, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37901270

RESUMO

Oxime esters are useful scaffolds in many organic chemistry transformations. Herein, a novel visible-light-mediated three-component reaction for synthesis of oxime esters is reported. Aldehydes, aniline, and N-hydroxyphthalimide (NHPI) esters were used as substrates in this three-component reaction, and eosin Y was used as a crucial photocatalyst for the reaction. Wide ranges of aldehydes and NHPI esters were well tolerated in this reaction method, generating various oxime esters with high efficiency under mild reaction conditions. This visible-light-mediated methodology will be a promising approach to synthesize useful oxime esters in a single step.

9.
Eur J Med Chem ; 261: 115779, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37776574

RESUMO

A series of 36 pyrazol-4-yl pyridine derivatives (8a-i, 9a-i, 10a-i, and 11a-i) was designed, synthesized, and evaluated for its antiproliferative activity over NCI-60 cancer cell line panel and inhibitory effect against JNK isoforms (JNK1, JNK2, and JNK3). All the synthesized compounds were tested against the NCI-60 cancer cell line panel. Compounds 11b, 11c, 11g, and 11i were selected to determine their GI50s and exerted a superior potency over the reference standard SP600125 against the tested cell lines. 11c showed a GI50 of 1.28 µM against K562 leukemic cells. Vero cells were used to assess 11c cytotoxicity compared to the tested cancer cells. The target compounds were tested against hJNK isoforms in which compound 11e exhibited the highest potency against JNK isoforms with IC50 values of 1.81, 12.7, and 10.5 nM against JNK1, JNK2, and JNK3, respectively. Kinase profiling of 11e showed higher JNK selectivity in 50 kinase panels. Compounds 11c and 11e showed cell population arrest at the G2/M phase, induced early apoptosis, and slightly inhibited beclin-1 production at higher concentrations in K562 leukemia cells relative to SP600125. NanoBRET assay of 11e showed intracellular JNK1 inhibition with an IC50 of 2.81 µM. Also, it inhibited CYP2D6 and 3A4 with different extent and its hERG activity showed little cardiac toxicity with an IC50 of 4.82 µM. hJNK3 was used as a template to generate the hJNK1 crystal structure to explore the binding mode of 11e (PDB ID: 8ENJ) with a resolution of 2.8 °A and showed a typical type I kinase inhibition against hJNK1. Binding energy scores showed that selectivity of 11e towards JNK1 could be attributed to additional hydrophobic interactions relative to JNK3.


Assuntos
Azóis , Proteínas Quinases JNK Ativadas por Mitógeno , Animais , Chlorocebus aethiops , Células Vero , Azóis/farmacologia , Isoformas de Proteínas , Piridinas/farmacologia , Proliferação de Células
10.
J Org Chem ; 88(18): 13291-13302, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37641453

RESUMO

A practical one-pot synthesis of esters and amides from tert-butyl esters via acid chloride was developed. Reactions of tert-butyl esters with α,α-dichlorodiphenylmethane as the chlorinating agent and SnCl2 as catalyst-generated acid chloride intermediates in situ were subsequently used in reactions with a variety of alcohols and amines to afford the corresponding esters and amides in high yields under mild reaction conditions. This catalytic synthetic procedure offers an effective strategy for the facile esterification and amidation of tert-butyl esters.

11.
Pharmaceutics ; 15(7)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37514026

RESUMO

Hypoxia, a deficiency in the levels of oxygen, is a common feature of most solid tumors and induces many characteristics of cancer. Hypoxia is associated with metastases and strong resistance to radio- and chemotherapy, and can decrease the accuracy of cancer prognosis. Non-invasive imaging methods such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) using hypoxia-targeting radiopharmaceuticals have been used for the detection and therapy of tumor hypoxia. Nitroimidazoles are bioreducible moieties that can be selectively reduced under hypoxic conditions covalently bind to intracellular macromolecules, and are trapped within hypoxic cells and tissues. Recently, there has been a strong motivation to develop PET and SPECT radiotracers as radiopharmaceuticals containing nitroimidazole moieties for the visualization and treatment of hypoxic tumors. In this review, we summarize the development of some novel PET and SPECT radiotracers as radiopharmaceuticals containing nitroimidazoles, as well as their physicochemical properties, in vitro cellular uptake values, in vivo biodistribution, and PET/SPECT imaging results.

12.
Int J Mol Sci ; 24(13)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37445730

RESUMO

Positron emission tomography (PET) is a noninvasive molecular imaging method extensively applied in the detection and treatment of various diseases. Hypoxia is a common phenomenon found in most solid tumors. Nitroimidazole is a group of bioreducible pharmacophores that selectively accumulate in hypoxic regions of the body. Over the past few decades, many scientists have reported the use of radiopharmaceuticals containing nitroimidazole for the detection of hypoxic tumors. Gallium-68, a positron-emitting radioisotope, has a favorable half-life time of 68 min and can be conveniently produced by 68Ge/68Ga generators. Recently, there has been significant progress in the preparation of novel 68Ga-labeled complexes bearing nitroimidazole moieties for the diagnosis of hypoxia. This review provides a comprehensive overview of the current status of developing 68Ga-labeled radiopharmaceuticals with nitroimidazole moieties, their pharmacokinetics, and in vitro and in vivo studies, as well as PET imaging studies for hypoxic tumors.


Assuntos
Nitroimidazóis , Humanos , Compostos Radiofarmacêuticos/farmacocinética , Radioisótopos de Gálio/farmacocinética , Linhagem Celular Tumoral , Tomografia por Emissão de Pósitrons/métodos , Hipóxia/diagnóstico por imagem
13.
RSC Adv ; 13(21): 14412-14434, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37180001

RESUMO

Sulfur dioxide-containing compounds such as sulfonyl fluorides, sulfonyl esters, and sulfonyl amides are important structural frameworks in many natural products, pharmaceuticals, and organic compounds. Thus, synthesis of these molecules is a very valuable research topic in organic chemistry. Various synthetic methods to introduce SO2 groups into the structure of organic compounds have been developed for the synthesis of biologically and pharmaceutically useful compounds. Recently, visible-light-driven reactions were carried out to create SO2-X (X = F, O, N) bonds, and their effective synthetic approaches were demonstrated. In this review, we summarized recent advances in visible-light-mediated synthetic strategies for generation of SO2-X (X = F, O, N) bonds for various synthetic applications along with proposed reaction mechanisms.

14.
Chem Biodivers ; 20(5): e202201030, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37017259

RESUMO

Herein, we report the design, synthesis and evaluation of novel (E)-3-(3-oxo-4-substituted-3,4-dihydro-2H-benzo[b][1,4]oxazin-6-yl)-N-hydroxypropenamides (4 a-i, 7 a-g) targeting histone deacetylases. Three human cancer cell lines were used to test the cytotoxicity of the synthesized compounds (SW620, colon; PC-3, prostate; NCI-H23, lung cancer); inhibitory activity towards HDAC; anticancer activity; as well as their impact on the cell cycle and apoptosis. As a result, compounds 4 a-i bearing the alkyl substituents seemed to be less potent than the benzyl-containing compounds 7 a-g in all biological assays. Compounds 7 e-f were found to be the most active HDAC inhibitors with IC50 of 1.498±0.020 µM and 1.794±0.159 µM, respectively. In terms of cytotoxicity and anticancer assay, 7 e and 7 f also showed good activity with IC50 values in the micromolar range. In addition, the cell cycle and apoptosis of SW620 were affected by compound 7 f in almost a similar manner to that of reference compound SAHA. Docking assays were carried out for analysis the binding mode and selectivity of this compound toward 8 HDAC isoforms. Overall, our data confirmed that the inhibition of HDAC plays a pivotal role in their anticancer activity.


Assuntos
Antineoplásicos , Inibidores de Histona Desacetilases , Humanos , Inibidores de Histona Desacetilases/química , Relação Estrutura-Atividade , Antineoplásicos/química , Linhagem Celular Tumoral , Ácidos Hidroxâmicos , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células , Desenho de Fármacos , Simulação de Acoplamento Molecular
15.
J Stroke ; 25(2): 242-250, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37032475

RESUMO

BACKGROUND AND PURPOSE: Moderate-intensity statin plus ezetimibe versus high-intensity statin alone may provide a greater low-density lipoprotein cholesterol (LDL-C) reduction in patients with recent ischemic stroke. METHODS: This randomized, open-label, controlled trial assigned patients with recent ischemic stroke <90 days to rosuvastatin/ezetimibe 10/10 mg once daily (ROS10/EZT10) or to rosuvastatin 20 mg once daily (ROS20). The primary endpoint was LDL-C reduction ≥50% from baseline at 90 days. Key secondary endpoints were LDL-C <70 mg/dL and multiple lipid goal achievement, and composite of major vascular events. RESULTS: Of 584 randomized, 530 were included in the modified intention-to-treat analysis. The baseline LDL-C level was 130.2±34.7 mg/dL in the ROS10/EZT10 group and 131.0±33.9 mg/dL in the ROS20 group. The primary endpoint was achieved in 198 patients (72.5%) in the ROS10/EZT10 group and 148 (57.6%) in the ROS20 group (odds ratio [95% confidence interval], 1.944 [1.352-2.795]; P= 0.0003). LDL-C level <70 mg/dL was achieved in 80.2% and 65.4% in the ROS10/EZT10 and ROS20 groups (P=0.0001). Multiple lipid goal achievement rate was 71.1% and 53.7% in the ROS10/EZT10 and ROS20 groups (P<0.0001). Major vascular events occurred in 1 patient in the ROS10/EZT10 group and 9 in the ROS20 group (P=0.0091). The adverse event rates did not differ between the two groups. CONCLUSION: Moderate-intensity rosuvastatin plus ezetimibe was superior to high-intensity rosuvastatin alone for intensive LDL-C reduction in patients with recent ischemic stroke. With the combination therapy, more than 70% of patients achieved LDL-C reduction ≥50% and 80% had an LDL-C <70 mg/dL at 90 days.

16.
Molecules ; 28(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36985708

RESUMO

A heterocycle is an important structural scaffold of many organic compounds found in pharmaceuticals, materials, agrochemicals, and biological processes. Azacycles are one of the most common motifs of a heterocycle and have a variety of applications, including in pharmaceuticals. Therefore, azacycles have received significant attention from scientists and a variety of methods of synthesizing azacycles have been developed because their efficient synthesis plays a vital role in the production of many useful compounds. In this review, we summarize recent approaches to preparing azacycles via different methods as well as describe plausible reaction mechanisms.

17.
Bone ; 171: 116743, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36958542

RESUMO

BACKGROUND: Assessment of cortical bone porosity and geometry by imaging in vivo can provide useful information about bone quality that is independent of bone mineral density (BMD). Ultrashort echo time (UTE) MRI techniques of measuring cortical bone porosity and geometry have been extensively validated in preclinical studies and have recently been shown to detect impaired bone quality in vivo in patients with osteoporosis. However, these techniques rely on laborious image segmentation, which is clinically impractical. Additionally, UTE MRI porosity techniques typically require long scan times or external calibration samples and elaborate physics processing, which limit their translatability. To this end, the UTE MRI-derived Suppression Ratio has been proposed as a simple-to-calculate, reference-free biomarker of porosity which can be acquired in clinically feasible acquisition times. PURPOSE: To explore whether a deep learning method can automate cortical bone segmentation and the corresponding analysis of cortical bone imaging biomarkers, and to investigate the Suppression Ratio as a fast, simple, and reference-free biomarker of cortical bone porosity. METHODS: In this retrospective study, a deep learning 2D U-Net was trained to segment the tibial cortex from 48 individual image sets comprised of 46 slices each, corresponding to 2208 training slices. Network performance was validated through an external test dataset comprised of 28 scans from 3 groups: (1) 10 healthy, young participants, (2) 9 postmenopausal, non-osteoporotic women, and (3) 9 postmenopausal, osteoporotic women. The accuracy of automated porosity and geometry quantifications were assessed with the coefficient of determination and the intraclass correlation coefficient (ICC). Furthermore, automated MRI biomarkers were compared between groups and to dual energy X-ray absorptiometry (DXA)- and peripheral quantitative CT (pQCT)-derived BMD. Additionally, the Suppression Ratio was compared to UTE porosity techniques based on calibration samples. RESULTS: The deep learning model provided accurate labeling (Dice score 0.93, intersection-over-union 0.88) and similar results to manual segmentation in quantifying cortical porosity (R2 ≥ 0.97, ICC ≥ 0.98) and geometry (R2 ≥ 0.82, ICC ≥ 0.75) parameters in vivo. Furthermore, the Suppression Ratio was validated compared to established porosity protocols (R2 ≥ 0.78). Automated parameters detected age- and osteoporosis-related impairments in cortical bone porosity (P ≤ .002) and geometry (P values ranging from <0.001 to 0.08). Finally, automated porosity markers showed strong, inverse Pearson's correlations with BMD measured by pQCT (|R| ≥ 0.88) and DXA (|R| ≥ 0.76) in postmenopausal women, confirming that lower mineral density corresponds to greater porosity. CONCLUSION: This study demonstrated feasibility of a simple, automated, and ionizing-radiation-free protocol for quantifying cortical bone porosity and geometry in vivo from UTE MRI and deep learning.


Assuntos
Aprendizado Profundo , Osteoporose Pós-Menopausa , Osteoporose , Humanos , Feminino , Osteoporose Pós-Menopausa/diagnóstico por imagem , Estudos Retrospectivos , Porosidade , Osso Cortical/diagnóstico por imagem , Densidade Óssea , Imageamento por Ressonância Magnética/métodos
18.
Radiology ; 307(2): e221810, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36692396

RESUMO

Background Preclinical studies have suggested that solid-state MRI markers of cortical bone porosity, morphologic structure, mineralization, and osteoid density are useful measures of bone health. Purpose To explore whether MRI markers of cortical bone porosity, morphologic structure, mineralization, and osteoid density are affected in postmenopausal osteoporosis (OP) and to examine associations between MRI markers and bone mineral density (BMD) in postmenopausal women. Materials and Methods In this single-center study, postmenopausal women were prospectively recruited from January 2019 to October 2020 into two groups: participants with OP who had not undergone treatment, defined as having any dual-energy x-ray absorptiometry (DXA) T-score of -2.5 or less, and age-matched control participants without OP (hereafter, non-OP). Participants underwent MRI in the midtibia, along with DXA in the hip and spine, and peripheral quantitative CT in the midtibia. Specifically, MRI measures of cortical bone porosity (pore water and total water), osteoid density (bound water [BW]), morphologic structure (cortical bone thickness), and mineralization (phosphorous [P] density [31P] and 31P-to-BW concentration ratio) were quantified at 3.0 T. MRI measures were compared between OP and non-OP groups and correlations with BMD were assessed. Results Fifteen participants with OP (mean age, 63 years ± 5 [SD]) and 19 participants without OP (mean age, 65 years ± 6) were evaluated. The OP group had elevated pore water (11.6 mol/L vs 9.5 mol/L; P = .007) and total water densities (21.2 mol/L vs 19.7 mol/L; P = .03), and had lower cortical bone thickness (4.8 mm vs 5.6 mm; P < .001) and 31P density (6.4 mol/L vs 7.5 mol/L; P = .01) than the non-OP group, respectively, although there was no evidence of a difference in BW or 31P-to-BW concentration ratio. Pore and total water densities were inversely associated with DXA and peripheral quantitative CT BMD (P < .001), whereas cortical bone thickness and 31P density were positively associated with DXA and peripheral quantitative CT BMD (P = .01). BW, 31P density, and 31P-to-BW concentration ratio were positively associated with DXA (P < .05), but not with peripheral quantitative CT. Conclusion Solid-state MRI of cortical bone was able to help detect potential impairments in parameters reflecting porosity, morphologic structure, and mineralization in postmenopausal osteoporosis. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Bae in this issue.


Assuntos
Osteoporose Pós-Menopausa , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Osteoporose Pós-Menopausa/diagnóstico por imagem , Porosidade , Densidade Óssea , Absorciometria de Fóton , Osso Cortical/diagnóstico por imagem , Água , Imageamento por Ressonância Magnética
19.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-967415

RESUMO

Background@#A study on coronavirus disease 2019 (COVID-19) phobia among students revealed that fear of contracting COVID-19 was associated with commuting to school and spending time with others at school. Therefore, it is the need-of-the-hour for the Korean government to identify factors affecting COVID-19 phobia among university students and to consider these factors while framing the policy direction for the process of returning to normalcy in university education. Consequently, we aimed to identify the current state of COVID-19 phobia among Korean undergraduate and graduate students and the factors affecting COVID-19 phobia. @*Methods@#This cross-sectional survey was conducted to identify the factors affecting COVID-19 phobia among Korean undergraduate and graduate students. The survey collected 460 responses from April 5 to April 16, 2022. The questionnaire was developed based on the COVID-19 Phobia Scale (C19P-S). Multiple linear regression was performed on the C19P-S scores using five models with the following dependent variables: Model 1, total C19P-S score; Model 2, psychological subscale score; Model 3, psychosomatic subscale score; Model 4, social subscale score; and Model 5, economic subscale score. The fit of these five models was established, and a P-value of less than 0.05 (F test) was considered statistically significant. @*Results@#An analysis of the factors affecting the total C19P-S score led to the following findings: women significantly outscored men (difference: 4.826 points, P = 0.003); the group that favored the government’s COVID-19 mitigation policy scored significantly lower than those who did not favor it (difference: 3.161 points, P = 0.037); the group that avoided crowded places scored significantly higher than the group that did not avoid crowded places (difference: 7.200 points, P < 0.001); and those living with family/friends scored significantly higher than those in other living situations (difference: 4.606 points, P = 0.021). Those in favor of the COVID-19 mitigation policy had significantly lower psychological fear than those who were against it (difference: -1.686 points, P = 0.004). Psychological fear was also significantly higher for those who avoided crowded places compared to those who did not difference: 2.641 points, P < 0.001). Fear was significantly higher in people cohabitating than those living alone (difference: 1.543 points, P= 0.043). @*Conclusion@#The Korean government, in their pursuit of a policy that eases COVID-19-related restrictions, will also have to spare no efforts in providing correct information to prevent the escalation of COVID-19 phobia among people with a high fear of contracting the disease. This should be done through trustworthy information sources, such as the media, public agencies, and COVID-19 professionals.

20.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-967818

RESUMO

Background@#Korea recently established 70 emergency medical service areas. However, there are many concerns that medical resources for stroke could not be evenly distributed through the country. We aimed to compare the treatment quality and outcomes of acute stroke among the emergency medical service areas. @*Methods@#This study analyzed the data of 28,800 patients admitted in 248 hospitals which participated in the 8th acute stroke quality assessment by Health Insurance Review and Assessment Service. Individual hospitals were regrouped into emergency service areas according to the address of the location. Assessment indicators and fatality were compared by the service areas. We defined the appropriate hospital by the performance of intravenous thrombolysis. @*Results@#In seven service areas, there were no hospitals which received more than 10 stroke patients for 6 months. In nine service areas, there were no patients who underwent intravenous thrombolysis (IVT). Among 167 designated emergency medical centers, 50 hospitals (29.9%) responded that IVT was impossible 24 hours a day. There are 97 (39.1%) hospitals that meet the definitions of appropriate hospital. In 23 service areas (32.9%) had no appropriate or feasible hospitals. The fatality of service areas with stroke centers were 6.9% within 30 days and 15.6% within 1 year from stroke onset than those without stroke centers (7.7%, 16.9%, respectively). @*Conclusions@#There was a wide regional gap in the medical resource and the quality of treatments for acute stroke among emergency medical service areas in Korea. The poststroke fatality rate of the service areas which have stroke centers or appropriate hospitals were significantly low.

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