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1.
J Am Chem Soc ; 146(4): 2789-2797, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38236061

RESUMEN

Dearomative photocycloaddition of monocyclic arenes is an appealing strategy for comprehending the concept of "escape from flatland". This brings the replacement of readily available planar aromatic hydrocarbon units with a 3D fused bicyclic core with sp3-enriched carbon units. Herein, we outline an intermolecular approach for the dearomative photocycloaddition of phenols. In order to circumvent the ground-state aromaticity and to construct conformationally restrained building blocks, bicyclo[1.1.0]butanes were chosen as coupling partners. This dearomative approach renders straightforward access to a bicyclo[2.1.1]hexane unit fused to a cyclic enone moiety, which further contributed as a synthetic linchpin for postmodifications. Mechanistic experiment advocates for a plausible onset from both the reactants, depending on the redox potential.

2.
Plant Dis ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38587803

RESUMEN

Euonymus japonicus Thunb., also known as the evergreen spindle tree, is an evergreen tree, which is widely planted as a hedge plant along streets in South Korea. In April 2022, severe anthracnose symptoms were observed on the leaves of this tree in Jangsu in the Jeonbuk Province of the country (35°43'49.44″N, 127°34'53.7″E). About 80% of the leaves of each affected tree within a 0.03-ha area showed incidence of the disease on approximately 30 trees were planted along the roadside (~30 m). These symptoms typically included circular or irregularly shaped whitish-gray lesions with a diameter of 2.0 to 3.0 cm. In cases where some leaves were severely affected, larger blotches formed. To isolate the pathogen, about ten leaves showing anthracnose symptoms on each tree were randomly selected and brought to the laboratory. Fungal isolations were made from acervuli filled with conidial masses on infected evergreen tissues, followed by plating onto 2% potato dextrose agar (PDA) as well as incubated at 25℃. On the PDA, colonies were circular, raised, green-grey or dark grey, and had a distinct white margin. The conidia were single-celled, transparent, cylindrical with rounded ends, had smooth walls, with a length ranging from 12 µm to 16.7 µm and a width raging from 4 µm to 6.5 µm (av. = 14.1 X 5.0 µm, n=40). Of those that were successfully recovered with approximately 90% frequency, two monoconidial isolates were deposited to the culture collection at Chungnam National University in South Korea (Accession number: CDH059-060). To ensure the identity of the fungus, genomic DNAs were extracted from the selected isolates, CDH059-060, and were sequenced. This was achieved based on partial sequences of the internal transcribed spacer (ITS), actin and beta-tubulin (TUB2) gene regions which were amplified using ITS1F / ITS4 (Gardes and Bruns 1993; White et al. 1990), ACT-512F / ACT-783R (Carbone and Kohn 1999), and T1 / Bt2b (O'Donnell and Cigelnik 1997; Glass and Donaldson 1995) primer pairs, respectively. The resulting sequences were deposited to GenBank (OR984424-425) for ITS, (OR996289-290) for actin, and (OR996291-292) for TUB2. For a phylogenetic analysis, sequences from different gene regions (ITS, actin and TUB2) retrieved from GenBank were aligned, concatenated, and analyzed as a single dataset based on a maximum likelihood analysis. The phylogenetic result revealed that the fungus isolated in this study was positioned in a clearly distinct lineage, provisionally representing an undetermined species of Colletotrichum, which is most closely related to Colletotrichum liaoningense (Y.Z. Diao, C. Zhang, L. Cai & X.L. Liu, CGMCC3.17616 (KP890104 for ITS, KP890097 for actin, and KP890111 for TUB, Diao et al. 2017). Sequence comparisons revealed that this pathogen differed from C. liaoningense at 20 of 494 characters (∼4.0%) in the ITS and 2 of 251 (∼1.0%) in the actin sequences. For pathogenicity tests, three seedlings of E. japonicus were used. The leaves for each tree were treated with 10 ml of a conidial suspension by spraying (1x106 conidia ml-1 of the isolate, CDH059), while the three seedlings were treated with distilled water as control. After sprayed, the treated areas were sealed with plastic bags for a day to maintain humidity. Anthracnose symptoms identical to those observed in the field appeared seven days after inoculations, while no symptoms were observed in the control. Re-isolations were successfully achieved from the treatments, fulfilling Koch's postulates. Anthracnose associated with the provisionally novel species of Colletotrichum sp. on E. japonicus has not been recorded elsewhere, and in this regard, this is the first report of anthracnose caused by Colletotrichum sp. on E. japonicus in Korea. To effectively control the disease, more attention should be paid to the host range of the pathogen and other regions where the disease caused by the pathogen might occur in the country.

3.
Plant Dis ; 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38512194

RESUMEN

Machilus thunbergii Siebold & Zucc., known as Japanese bay tree, is an evergreen tree distributed widely in East Asia, including South Korea, where the species is of ecological importance. Machilus thunbergii provides habitat for wildlife species and is a common urban tree. In September 2022, anthracnose symptoms on leaves were observed in Jeju (33°26'02.4"N, 126°19'48.8"E) and Tongyeong (34°49'27.1"N, 128°24'01.8"E) in South Korea. Disease incidence on leaves of each affected tree, naturally growing in an urban forest area covering approximately 0.5 ha was approximately ~ 70 % in each study area. Anthracnose symptoms that were observed on 70 to 80% leaves per tree in each study area included orbicular or irregular, whitish-grey spots on leaves that were 1.5 to 3.0 cm in diam. In some cases where leaves were severely affected, larger blotches were formed, leading to bleaching symptoms and eventually defoliation. For pathogen isolation, two or three leaves showing anthracnose symptoms from each of the 15 trees were randomly selected and brought to the laboratory. Fungal isolations were then directly made by transferring spores from acervuli that developed on diseased leaves onto potato dextrose agar (PDA) media. Cushion shaped acervuli filled with salmon to orange-colored conidial masses were produced on media approximately two weeks after the incubation at 25 ± 1°C with a photoperiod of 12 h. Conidia were single celled, hyaline, cylindrical with rounded ends, smooth walls, 13.7 to 18.1 µm long and 3.1 to 4.5 µm wide (n=30). Among 15 cultures that were successfully isolated, 10 isolates were retained based on culture characteristics, and two randomly selected monoconidial cultures were deposited in the culture collection (CDH) of the Chungnam National University, Republic of Korea (Accession No. CDH057-58). Two isolates selected, CDH057 and CDH058, were subjected to identification, and this was achieved based on multiplesequence comparisons using on internal transcribed spacer regions of rDNA (ITS1 and ITS2), partial sequences of actin (ACT) and ß-tubulin (TUB2) gene regions amplified using ITS1F / ITS4, ACT-512F / ACT-783R and T1 / Bt2b, respectively (Weir et al. 2012). The representative sequence data were deposited in GenBank under the accession numbers OR473277 and OR473278 for the ITS, OR480772 and OR480773 for ACT, and OR480774 and OR480775 for TUB2. The resulting sequences were further used for a phylogenetic analysis based on the maximum likelihood method using a concatenated dataset of the ITS, ACT and TUB2 gene sequences for Colletotrichum species in the C. gloeosporioides clade. The results showed that the pathogen isolated in this study clustered with Colletotrichum siamense (Vouchered specimens: MFLU 090230, COUFPI291, and COUFPI294) (Prihastuti et al. 2009). Sequence comparisons revealed that the isolates obtained in this study differed from the type species of C. siamense (MFLU 090230; FJ972613 for ITS, FJ 907423 for ACT, FJ907438 for TUB2) at 2 of 258 bp (∼0.8%) and 6 of 387 bp (∼1.6%) in the ACT and TUB2 sequences, respectively, while the ITS was identical to the type species. For pathogenicity tests, a total of ten three-year-old seedlings of M. thunbergii were used. The leaves of each tree were sprayed with 5 ml of conidial suspension (105 conidia/ml, isolate CDH057). Three control plants were sprayed with sterile water. After being sprayed, treated areas were sealed with a plastic bag for 24 hours to preserve humidity. Anthracnose symptoms, identical to those observed in the field, appeared five to seven days after the inoculations, while no symptoms were observed on control plants. The isolates used in the pathogenicity test were reisolated from 90% of lesions, and their identity was confirmed based on sequence comparisons, thus fulfilling Koch's postulates. Species of the C. gloeosporioides species complex include important plant pathogens, particularly C. siamense, which cause significant losses of economic and ecological relevance on a wide range of hosts (~ 100 hosts) (Talhinhas and Baroncelli 2021). Although C. fioriniae in the C. acutatum species complex, was found on M. thunbergii in South Korea (Thao et al. 2023), anthracnose associated with C. siamense on M. thunbergii has not been reported in the country. In this regard, this is the first report of anthracnose caused by C. siamense on M. thunbergii in South Korea. To effectively control the disease, more attention should be paid on the host range of the pathogen and other regions where the disease caused by the pathogen might occur in the country.

4.
Sensors (Basel) ; 24(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38732913

RESUMEN

The Controller Area Network (CAN), widely used for vehicular communication, is vulnerable to multiple types of cyber-threats. Attackers can inject malicious messages into the CAN bus through various channels, including wireless methods, entertainment systems, and on-board diagnostic ports. Therefore, it is crucial to develop a reliable intrusion detection system (IDS) capable of effectively distinguishing between legitimate and malicious CAN messages. In this paper, we propose a novel IDS architecture aimed at enhancing the cybersecurity of CAN bus systems in vehicles. Various machine learning (ML) models have been widely used to address similar problems; however, although existing ML-based IDS are computationally efficient, they suffer from suboptimal detection performance. To mitigate this shortcoming, our architecture incorporates specially designed rule-based filters that cross-check outputs from the traditional ML-based IDS. These filters scrutinize message ID and payload data to precisely capture the unique characteristics of three distinct types of cyberattacks: DoS attacks, spoofing attacks, and fuzzy attacks. Experimental evidence demonstrates that the proposed architecture leads to a significant improvement in detection performance across all utilized ML models. Specifically, all ML-based IDS achieved an accuracy exceeding 99% for every type of attack. This achievement highlights the robustness and effectiveness of our proposed solution in detecting potential threats.

5.
Sensors (Basel) ; 23(4)2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36850698

RESUMEN

Network pruning reduces the number of parameters and computational costs of convolutional neural networks while maintaining high performance. Although existing pruning methods have achieved excellent results, they do not consider reconstruction after pruning in order to apply the network to actual devices. This study proposes a reconstruction process for channel-based network pruning. For lossless reconstruction, we focus on three components of the network: the residual block, skip connection, and convolution layer. Union operation and index alignment are applied to the residual block and skip connection, respectively. Furthermore, we reconstruct a compressed convolution layer by considering batch normalization. We apply our method to existing channel-based pruning methods for downstream tasks such as image classification, object detection, and semantic segmentation. Experimental results show that compressing a large model has a 1.93% higher accuracy in image classification, 2.2 higher mean Intersection over Union (mIoU) in semantic segmentation, and 0.054 higher mean Average Precision (mAP) in object detection than well-designed small models. Moreover, we demonstrate that our method can reduce the actual latency by 8.15× and 5.29× on Raspberry Pi and Jetson Nano, respectively.

6.
Curr Issues Mol Biol ; 44(11): 5139-5152, 2022 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-36354662

RESUMEN

Tumor budding (TB) is a small cluster of malignant cells at the invasive front of a tumor. Despite being an adverse prognosis marker, little research has been conducted on the tumor immune microenvironment of tumor buddings, especially in cervical cancer. Therefore, RNA sequencing was performed using 21 formalin-fixed, paraffin-embedded slides of cervical tissues, and differentially expressed genes (DEGs) were analyzed. Immune Pathway and Gene Database (IMPAGT) was generated for immune profiling. "Pathway in Cancer" was identified as the most enriched pathway for both up- and downregulated DEGs. Kyoto Encyclopedia of Genes and Genomes Mapper and Gene Ontology further revealed the activation of the PI3K/Akt signaling pathway. An IMPAGT analysis revealed immune dysregulation even at the tumor budding stage, especially in the PI3K/Akt/mTOR axis, with a high efficiency and integrity. These findings emphasized the clinical significance of tumor buddings and the necessity of blocking the overactivation of the PI3K/Akt/mTOR pathway to improve targeted therapy in cervical cancer.

7.
Plant Dis ; 2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35657713

RESUMEN

Walnut (Juglans regia) is one of the main tree crops cultivated for nut production in South Korea with an estimated production of about 1,189 tons per year (Korea Forest Service 2020). In August 2021, anthracnose symptoms, including dark, depressed, irregularly shaped lesions on fruits and leaves of walnut cv. Sinlyeong, were observed at three orchards in Nonsan (36°10'22.5"N 127°06'14.8"E) and Suwon (37°16'04.7"N 126°55'22.3"E and 37°15'10.6"N 126°57'35.6"E). This led to severe yield loss of walnut fruit with a disease incidence of approximately 70 to 80% in each orchard. Three samples, including infected fruits and leaves, were randomly collected per site. Fungal isolates were isolated either from acervuli filled with conidial masses on infected walnut tissues or from plant tissues that were surface-disinfested, followed by plating onto 2% PDA. Colonies were initially white, later became pale brownish to light gray with concentric rings of salmon sporodochia. White to gray aerial mycelia, reaching 65 mm diameter in 5 days, were abundantly produced on PDA at 25 °C. Appressoria were brown, ovoid, and in some cases, clavate, 5.1-8.7 µm in length, and 3.2-5.1 µm in width (n = 50). Conidia were single celled, hyaline, cylindrical with rounded ends and smooth walls, guttulate, 13.6-18.8 µm in length, and 4.4-6.3 µm in width (n = 50). Setae were absent. Three isolates, i.e., one per orchard, were retained and deposited in the culture collection (CDH) of National Institute of Forest Science, Korea (Accession No. CDH052-054). The internal transcribed spacer (ITS) region of rDNA, beta-tubulin (TUB2) and a partial sequence of the actin (ACT) genes were amplified and sequenced for each of the isolates using the pair of primers, ITS1F/ITS4 (Gardes and Bruns 1993; White et al. 1990), T1/Bt2b (ODonnell and Cigelnik 1997; Glass and Donaldson 1995) and ACT-512F/ACT-783R (Carbone and Kohn 1999), respectively. A BLAST search in GenBank revealed that the sequences of ITS (OK631731-733), TUB2 (OK665927-929) and ACT (OK665930-932) showed sequence identities of 98.6 to 99.6% to Colletotrichum siamense sequences (FJ972613, FJ907423, FJ907438). A maximum likelihood tree, based on a combined dataset of ITS, ACT and TUB2 gene sequences for Colletotrichum spp., revealed that the three isolates were clustered with type specimens of C. siamense. To prepare larger quantities of inoculum for the pathogenicity, mycelial plugs bearing acervuli taken from 2% PDA were incubated in a conical flask containing 200 ml of 2% potato dextrose broth at 25°C on a rotary shaker at 150 rpm for two weeks. Spore concentration was adjusted to 1.0 × 104 ml-1 conidia of C. siamense (CDH054). A 10 to 15 ml of spore suspension was then sprayed on each leaf of 12 seedlings of 'Sinlyeong' walnut (three-year-old), while 7 seedlings were treated with sterile distilled water as a control. Each treated seedling was covered by a plastic bag to maintain moisture for one day. Inoculation trials were repeated twice, in August and September 2021. Symptoms identical to those observed in the field developed four to five days after the inoculations from which the inoculated pathogen was successfully re-isolated, fulfilling Koch's postulates. However, no symptoms were observed in the control. To our knowledge, this is the first report of anthracnose on J. regia caused by C. siamense in Korea. This indicates that disease occurrences must be further rigorously surveyed at the nation-wide scale to effectively control the disease in the country.

8.
J Xray Sci Technol ; 30(3): 549-566, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35253722

RESUMEN

BACKGROUND: Dual-energy computed tomography (DECT) is a widely used and actively researched imaging modality that can estimate the physical properties of an object more accurately than single-energy CT (SECT). Recently, iterative reconstruction methods called one-step methods have received attention among various approaches since they can resolve the intermingled limitations of the conventional methods. However, the one-step methods typically have expensive computational costs, and their material decomposition performance is largely affected by the accuracy in the spectral coefficients estimation. OBJECTIVE: In this study, we aim to develop an efficient one-step algorithm that can effectively decompose into the basis material maps and is less sensitive to the accuracy of the spectral coefficients. METHODS: By use of a new loss function that employs the non-linear forward model and the weighted squared errors, we propose a one-step reconstruction algorithm named generalized simultaneous algebraic reconstruction technique (GSART). The proposed algorithm was compared with the image-domain material decomposition and other existing one-step reconstruction algorithm. RESULTS: In both simulation and experimental studies, we demonstrated that the proposed algorithm effectively reduced the beam-hardening artifacts thereby increasing the accuracy in the material decomposition. CONCLUSIONS: The proposed one-step reconstruction for material decomposition in dual-energy CT outperformed the image-domain approach and the existing one-step algorithm. We believe that the proposed method is a practically very useful addition to the material-selective image reconstruction field.

9.
Nutr Metab Cardiovasc Dis ; 31(1): 254-262, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33097412

RESUMEN

BACKGROUND AND AIMS: Women with obesity are highly predominant among patients with heart failure with preserved ejection fraction (HFpEF). We aimed to elucidate sex-specific associations of obesity with exercise capacity and diastolic function. METHODS AND RESULTS: Healthy individuals without known cardiovascular diseases undergoing cardiopulmonary exercise test and echocardiography (n = 736) were included and categorized into 4 groups according to their sex and obesity. Exercise capacity was lower in women than men. Obesity was associated with a lower exercise capacity in women (23.5 ± 7.3 vs. 21.3 ± 5.4 ml/kg/min, p < 0.05) but not in men (28.2 ± 7.8 vs. 28.0 ± 6.6 ml/kg/min, p > 0.10). Overall, women had a higher E/e' than men. Women without obesity had a similar E/e' to men with obesity (8.2 ± 1.8 vs. 8.4 ± 2.1, p > 0.10), and women with obesity had the highest E/e'. Among 5 risk factors (aging, obesity, elevated blood pressure, elevated heart rate, and elevated fasting glucose), obesity was a significant determinant of exercise intolerance in women but not men. Furthermore, obesity was associated with a greater risk of diastolic dysfunction in women than men (women, adjusted odds ratio 4.35 [95% confidence interval 2.44-7.74]; men, adjusted odds ratio 2.91 [95% confidence interval 1.42-5.95]). CONCLUSION: Obesity had a more deleterious effect on exercise capacity and diastolic function in women than men, even in a healthy cohort. These subclinical changes might contribute to the development of a female predominance among HFpEF patients, particularly among individuals with obesity.


Asunto(s)
Tolerancia al Ejercicio , Insuficiencia Cardíaca/fisiopatología , Obesidad/fisiopatología , Disfunción Ventricular Izquierda/fisiopatología , Función Ventricular Izquierda , Adulto , Anciano , Estudios Transversales , Diástole , Femenino , Disparidades en el Estado de Salud , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Obesidad/diagnóstico , Obesidad/epidemiología , República de Corea/epidemiología , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/epidemiología , Adulto Joven
10.
Plant Dis ; 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33858184

RESUMEN

In 2020, severely infected fruit of pecan, Carya illinoiensis, showing distinct anthracnose symptoms were observed from pecan orchards in Uiseong (36°21'31.5"N 128°27'15.9"E) and Miryang (35°22'54.9"N 128°48'06.5"E) in South Korea. Visible symptoms occurred on fruit of the tree between June and July, which included dark, depressed and covered with irregularly shaped lesions. As the disease progressed, the lesions expanded and merged over time, leading to abscission of the fruit, which resulted in severe yield loss of pecan fruit. Of pecan varieties including Caddo, Giles and Peruque that were cultivated in each pecan orchard, Caddo appeared to be most susceptible to the disease. Estimated losses were approximately 30% and 70% for the Uiseong and Miryang pecan orchard, respectively. For pathogen isolation, ten symptomatic fruits of pecan were randomly collected and brought to the laboratory. The fruits were surface disinfested for 30 s with 70% ethanol and 1% sodium hypochlorite. These were then rinsed with sterile distilled water twice, placed in a humid chamber, and incubated at 25 ± 1°C with a photoperiod of 12 h. Acervuli filled with salmon-colored conidial masses were produced abundantly on the fruit a day after the incubation. Conidia were single celled, hyaline, cylindrical having rounded ends, smooth walls, guttulate, 15.5 to 17.7 µm long, and 3.4 to 4.8 µm wide (n = 20). Monoconidial isolates were made on 2% malt extract agar and incubated at 25°Ï¹ for two weeks in the dark condition. Of those that were successfully retained, two representative isolates from each orchard were deposited in the culture collection (CDH) of the National Institute of Forest Science, Korea (Accession No. CDH2020-17-18). To ensure the identity of the pathogen, molecular identification was made based on three gene regions, the internal transcribed spacer (ITS) region of rDNA, beta-tubulin (TUB2) gene and a partial sequence of the actin (ACT), which were amplified with ITS1F/ITS4, T1/Bt2b and ACT-512F/ACT-783R, respectively (Weir et al. 2012). These were then submitted to GenBank with accession numbers of MW380423-24 for ITS, MW387129-30 for TUB2 and MW387127-28 for ACT. A BLAST search in GenBank revealed that the sequences showed high similarity to those of Colletotrichum siamense, which were identical to MT434615 and MT274214 for ITS and ACT, respectively, and 99.7% to MK967337 for TUB2. Phylogenetic analysis based on the maximum likelihood method further showed that the isolates recovered in this study clustered with C. siamense, confirming its identity. Pathogenicity was confirmed by inoculating living pecan trees. Healthy fruits from five trees were surface cleaned with cotton soaked in sterile water and air-dried. To inoculate the pathogen, three to five fruit per tree were wounded with a sterilized needle, and an aliquot of 10 µl of spore suspension (1.0 × 105 conidia/ml) of C. siamense (CDH2020-18) was dropped on each wound. To keep moisture, each treated fruit was enveloped by a plastic bag where the cotton soaked in sterile water had been placed. Controls were treated with sterile distilled water drops. The symptoms with dark, depressed and irregularly shaped lesions developed from all inoculated treatments six weeks after the inoculations, which were identical to those observed in the field. However, no symptom was observed on the control. Colletotrichum siamense was successfully re-isolated, fulfilling Koch's postulates. Taken together, it was confirmed that C. siamense is the causal agent of anthracnose on pecan. In Korea, C. siamense was reported causing anthracnose on apple, persimmon and plum (Farr and Rossman 2020). However, to our knowledge, this is the first report of anthracnose on pecan caused by C. siamense in Korea. To control the disease effectively, more attention should be paid to other regions of the country where the disease caused by the pathogen might occur.

11.
J Org Chem ; 85(13): 8489-8500, 2020 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-32506910

RESUMEN

A three-component synthesis of multisubstituted fluorene derivatives has been developed by devising a rhodium-catalyzed stitching reaction/remote nucleophilic substitution sequence. A variety of nucleophiles can be installed in the second step including both heteroatom and carbon nucleophiles. An efficient synthesis of 5H-benzo[a]fluoren-5-ones has also been realized using N-(2-alkynyl)benzoylpyrrole as the reaction partner through a new reaction pathway.

12.
Lipids Health Dis ; 16(1): 172, 2017 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-28899385

RESUMEN

BACKGROUND: The purpose of this study was to describe and analyze the relationship between statin benefit groups based on statin-intensity class of drugs and coronary artery calcium score (CACS) using multidetector computed tomography (MDCT) in an asymptomatic Korean population. METHODS: A total of 3914 asymptomatic individuals (mean age: 55 ± 10 years; male: female = 2649: 1265) who underwent MDCT for health examination between January 2009 and December 2012 were retrospectively enrolled. They were categorized into three groups based on statin-intensity class of drugs (high-intensity (n = 1284, 32.8%); moderate-intensity (n = 1602, 40.9%) and low-intensity (n = 931, 23.8%) statin therapy groups) according to the American College of Cardiology (ACC)/American heart Association (AHA) 2013 guideline and the relationship between CACS and statin benefit group was analyzed. The statin benefit group was defined as individuals who should be considered moderate- and high-intensity statin therapy. RESULTS: Ten-year atherosclerotic cardiovascular disease (ASCVD; 12.6 ± 5.3% vs. 2.9 ± 1.9%, p < 0.001) and CACS (98 ± 270 vs. 3 ± 2, p < 0.001) were significantly higher in the high-intensity group compared to the moderate-intensity statin therapy group. In the high-intensity statin therapy group, age [odds ratio: 1.299 (1.137-1.483), p < 0.001], male gender [odds ratio: 44.252 (1.959-999.784), p = 0.001], and fasting blood glucose [odds ratio: 1.046 (1.007-1.087), p = 0.021] were independent risk factors associated with CACS ≥300 on multivariate logistic regression analysis. CONCLUSIONS: CACS on MDCT might be an important complementary tool for cardiovascular disease risk stratification. This study indicates that individualization of statin therapy as well as lifestyle modification will be useful in asymptomatic individuals, especially those in whom high-intensity statin therapy is required.


Asunto(s)
Calcio/metabolismo , Enfermedades Cardiovasculares/diagnóstico por imagen , Vasos Coronarios/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Anciano , Aterosclerosis/etiología , Aterosclerosis/prevención & control , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Vasos Coronarios/diagnóstico por imagen , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector/métodos , Factores de Riesgo
13.
Echocardiography ; 31(3): 285-92, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24007645

RESUMEN

INTRODUCTION: The aim of this study was to investigate the role of Doppler-derived left ventricular (LV) -dP/dt in predicting atrial fibrillation (AF) or ischemic stroke in patients with moderate to severe degenerative mitral regurgitation (MR). METHODS: Doppler-derived LV -dP/dt was determined from the continuous-wave Doppler spectrum of the MR jet (-dP/dt = 32/time between 3 and 1 m/sec) in 80 patients (mean age 59 ± 16 years, 41% men) with moderate to severe degenerative MR, normal LV ejection fraction (LVEF ≥ 60%), and sinus rhythm at diagnosis. Events were defined as new AF or ischemic stroke. RESULTS: During a mean follow-up of 18 ± 13 months, there were 9 events (6 new AF, 3 ischemic strokes). Univariate analysis showed that older age, decreased LV -dP/dt, increased LV mass index, and left atrial volume index (LAVI), shortened deceleration time (DT), reduced A' velocity, and elevated E/E' ratio, prolongation of pulmonary venous (PV) atrial reversal (AR) flow duration relative to mitral inflow A-wave duration (AR-Adur) were associated with events. In multivariate Cox regression analysis, Doppler-derived LV -dP/dt (for each 100 mmHg/sec increase, hazard ratio: 0.165, 95% confidence interval: 0.036-0.761, P = 0.021) and E/E' (hazard ratio: 0.820, 95% confidence interval: 0.682-0.987, P = 0.036) were significant independent predictors of AF or ischemic stroke. CONCLUSIONS: Doppler-derived LV -dP/dt is independently associated with the occurrence of AF or ischemic stroke in patients with moderate to severe degenerative MR and provides additional prognostic information.


Asunto(s)
Fibrilación Atrial/diagnóstico por imagen , Ecocardiografía Doppler/métodos , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Volumen Sistólico/fisiología , Accidente Cerebrovascular/diagnóstico por imagen , Adulto , Anciano , Fibrilación Atrial/etiología , Fibrilación Atrial/fisiopatología , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/etiología , Isquemia Encefálica/patología , Estudios de Cohortes , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/complicaciones , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Curva ROC , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/etiología , Disfunción Ventricular Izquierda/complicaciones , Disfunción Ventricular Izquierda/diagnóstico por imagen
14.
Korean J Ophthalmol ; 38(2): 122-128, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38351482

RESUMEN

PURPOSE: Various vitrectomy probes are currently being used commercially, and there are ongoing efforts toward developing probes with higher cutting rates and smaller gauges. This study aimed to compare the efficiency and safety of various commercially available small gauge ultrahigh-speed dual pneumatic vitrectomy probes. METHODS: We retrospectively analyzed the medical records of patients and recorded intraoperative videos while they underwent microincision three-port vitrectomy surgery for idiopathic epiretinal membrane at Soonchunhyang University Seoul Hospital. The patients were categorized into four groups based on the vitrectomy probe used during surgery: 23-7500 (UltraVit 23-gauge 7,500 cuts per minute [CPM]), 23-7500 (UltraVit 25-gauge 7,500 CPM), 25-10K (Advanced UltraVit 25-gauge 10,000 CPM), and 27-10K (Advanced UltraVit 27-gauge 10,000 CPM). RESULTS: In total, 82 eyes from 82 patients were included in this work, with 16, 11, 26, and 29 eyes in groups 23-7500, 25-7500, 25-10K, and 27-10K, respectively. The corresponding vitrectomy times were 295.56 ± 53.55, 293.09 ± 50.28, 299.92 ± 59.42, and 349.38 ± 67.23 seconds, respectively. There was a significant difference in the vitrectomy time between the groups (p = 0.004). The mean number of sutures was 3, 3, 2.96, and 0.83, respectively. In the 23-7500 group, there was one case of iatrogenic retinal break, while in the 27-10K group, there was one case of postoperative hypotony. CONCLUSIONS: Although advancements have been made in the 27-gauge vitrectomy probe, it still takes more vitrectomy time than it does when using the 23- and 25-gauge probes. However, the delay was within an average of 1 minute, and considering the significantly reduced need for sutures, there is a substantial benefit in terms of postoperative discomfort. Therefore, when choosing a probe for epiretinal membrane surgery among the four options, it is reasonable to select the 27-gauge probe according to the surgeon's preference.


Asunto(s)
Membrana Epirretinal , Perforaciones de la Retina , Humanos , Vitrectomía , Membrana Epirretinal/diagnóstico , Membrana Epirretinal/cirugía , Estudios Retrospectivos , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/cirugía , Ojo , Complicaciones Posoperatorias/cirugía
15.
Med Phys ; 51(2): 964-977, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38064641

RESUMEN

BACKGROUND: An energy-discriminating capability of a photon counting detector (PCD) can provide many clinical advantages, but several factors, such as charge sharing (CS) and pulse pileup (PP), degrade the capability by distorting the measured x-ray spectrum. To fully exploit the merits of PCDs, it is important to characterize the output of PCDs. Previously proposed PCD output models showed decent agreement with physical PCDs; however, there were still scopes to be improved: a global model-data mismatch and pixel-to-pixel variations. PURPOSES: In this study, we improve a PCD model by using count-rate-dependent model parameters to address the issues and evaluate agreement against physical PCDs. METHODS: The proposed model is based on the cascaded model, and we made model parameters condition-dependent and pixel-specific to deal with the global model-data mismatch and the pixel-to-pixel variation. The parameters are determined by a procedure for model parameter estimation with data acquired from different thicknesses of water or aluminum at different x-ray tube currents. To analyze the effects of having proposed model parameters, we compared three setups of our model: a model with default parameters, a model with global parameters, and a model with global-and-local parameters. For experimental validation, we used CdZnTe-based PCDs, and assessed the performance of the models by calculating the mean absolute percentage errors (MAPEs) between the model outputs and the actual measurements from low count-rates to high count-rates, which have deadtime losses of up to 24%. RESULTS: The outputs of the proposed model visually matched well with the PCD measurements for all test data. For the test data, the MAPEs averaged over all the bins were 49.2-51.1% for a model with default parameters, 8.0-9.8% for a model with the global parameters, and 1.2-2.7% for a model with the global-and-local parameters. CONCLUSION: The proposed model can estimate the outputs of physical PCDs with high accuracy from low to high count-rates. We expect that our model will be actively utilized in applications where the pixel-by-pixel accuracy of a PCD model is important.


Asunto(s)
Fotones , Tomografía Computarizada por Rayos X , Tomografía Computarizada por Rayos X/métodos , Rayos X
16.
Clin Genitourin Cancer ; 22(2): 224-236, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38042728

RESUMEN

INTRODUCTION: We aimed to provide a pathological perspective on the management of muscle-invasive bladder cancer (MIBC) by correlating the prechemotherapy transurethral resection of bladder tumor findings and postchemotherapy radiologic evaluation with final radical cystectomy (RC) findings. MATERIALS AND METHODS: This retrospective study included 79 MIBC patients treated with neoadjuvant chemotherapy (NAC) and RC. Pelvic diffusion-weighted magnetic resonance imaging (DW-MRI) and pathologic reports were retrieved from our institutional database. All pathology slides were reviewed based on diagnostic criteria with high interobserver reproducibility. RESULTS: Pathologic complete response (pCR) was confirmed in 32 patients (40.5%). The concordance and discordance between MRI and RC findings occurred in 68.3% and 31.7% of cases, respectively. The 21.5% of cases that were clinical CR (cCR) on MRI actually achieved pCR on RC specimens and 46.8% of cases that were non-cCR on MRI were actually non-pCR on RC specimens. In 19.0% of cases, RC findings were pCR, but MRI demonstrated residual tumor and the opposite was 12.7%. The greatest discrepancy between the 2 methods (75%, 3/4) was for the plasmacytoid subtype. Plasmacytoid histology was the most common histological subtype identified in RC specimens after NAC, followed by micropapillary and squamous histologies. CONCLUSIONS: We found that all cases with plasmacytoid and micropapillary subtypes, and squamous differentiation did not show pCR. In particular, the largest discrepancy between MRI findings and RC pathology after NAC was seen in the plasmacytoid subtype. An accurate pathologic diagnosis based on strict criteria to identify histological subtypes of MIBC is necessary for proper treatment.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de la Vejiga Urinaria , Humanos , Terapia Neoadyuvante/métodos , Imagen de Difusión por Resonancia Magnética , Estudios Retrospectivos , Reproducibilidad de los Resultados , Respuesta Patológica Completa , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología , Cistectomía/métodos , Imagen por Resonancia Magnética , Carcinoma de Células Escamosas/cirugía , Invasividad Neoplásica , Quimioterapia Adyuvante
17.
Life (Basel) ; 14(1)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38255705

RESUMEN

Tumor microenvironment (TME) plays a pivotal role in immuno-oncology, which investigates the intricate interactions between tumors and the human immune system. Specifically, tumor-infiltrating lymphocytes (TILs) are crucial biomarkers for evaluating the prognosis of breast cancer patients and have the potential to refine immunotherapy precision and accurately identify tumor cells in specific cancer types. In this study, we conducted tissue segmentation and lymphocyte detection tasks to predict TIL scores by employing self-supervised learning (SSL) model-based approaches capable of addressing limited labeling data issues. Our experiments showed a 1.9% improvement in tissue segmentation and a 2% improvement in lymphocyte detection over the ImageNet pre-training model. Using these SSL-based models, we achieved a TIL score of 0.718 with a 4.4% improvement. In particular, when trained with only 10% of the entire dataset, the SwAV pre-trained model exhibited a superior performance over other models. Our work highlights improved tissue segmentation and lymphocyte detection using the SSL model with less labeled data for TIL score prediction.

18.
Life (Basel) ; 14(4)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38672714

RESUMEN

Tumor-associated macrophages (TAMs) play a pivotal role in the tumor microenvironment, influencing cancer progression and contributing to poor prognosis. However, in cervical cancer (CC), their significance and involvement are relatively less studied than in other gynecological cancers such as ovarian and endometrial cancer. This review aims to provide an overview of TAMs, covering their origins and phenotypes and their impact on CC progression, along with major TAM-targeted therapeutic approaches. Furthermore, we advocate for the integration of cutting-edge research methodologies, such as single-cell RNA sequencing and spatial RNA sequencing, to enable in-depth and comprehensive investigations into TAMs in CC, which would be beneficial in leading to more personalized and effective immunotherapy strategies for patients with CC.

19.
Biosci Microbiota Food Health ; 43(1): 73-80, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38188664

RESUMEN

The reasons for sex-associated gut microbiota differences have not been determined, and although sex hormones, diet, and other factors are considered to contribute to them, many of these factors are age related. To shed light on this complex interplay, our study aimed to investigate and compare the gut microbial compositions of males and females across a broad range of ages, aiming to identify sex-associated disparities and potential causal factors. Our study encompassed a comprehensive analysis of gut microbiota data obtained from 444 Japanese individuals, ranging from newborns to centenarians, sourced from the DNA Data Bank of Japan. We categorized the subjects into 13 distinct age groups and examined their relative microbial abundances, as well as alpha and beta diversities, in relation to sex and age. No difference was observed between gut microbiota relative abundances or alpha diversities between men and women at any age. However, the study showed that the heterogeneity of gut microbiota among women in their 20s was greater than in men. To confirm the general occurrence of this difference, we conducted additional analyses using seven datasets: three from Japan and four from other countries. Interestingly, this variance was particularly noticeable within Japanese women. We also showed a potential link between the observed heterogeneity and dietary fiber intake. It is hoped this study will provide clues that aid in the identification of factors responsible for sex-associated differences in gut microbiota compositions.

20.
In Vivo ; 38(1): 372-379, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38148060

RESUMEN

BACKGROUND/AIM: This study evaluated the possibility of clinical use of circulating-tumor DNA (ctDNA) as a biomarker to determine up-front autologous stem cell transplantation (auto-SCT) for patients with high-risk diffuse large B-cell lymphoma (DLBCL) in practice. PATIENTS AND METHODS: To explore the dynamics of ctDNA in DLBCL, blood samples were collected sequentially before and after treatment from patients with newly diagnosed DLBCL who received rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy. To conduct ctDNA genotyping and ctDNA monitoring simultaneously, targeted sequencing by cancer personalized profiling using deep sequencing was used. RESULTS: Ten patients between the ages of 50 and 60 years were enrolled. Based on the international prognostic index (IPI), seven patients were classified as high-IPI-risk group, and three patients were classified as low-IPI-risk group. The IPI risk group correlated with total metabolic tumor volume. All patients completed six cycles of R-CHOP chemotherapy, and seven patients achieved complete response. Changes in ctDNA mutation numbers did not correlate with changes in PET scan images and treatment response. In most high-risk patients, new mutations appeared in ctDNA after completion of chemotherapy that conceivably marked resistant clones. Notably, disease relapse did not occur in high-risk patients with poor prognostic mutations who underwent autologous SCT. CONCLUSION: ctDNA monitoring was meaningful in high-risk patients. Moreover, ctDNA and well-known prognostic factors should be considered in the decision making for auto-SCT. If a new genetic mutation in ctDNA with a negative prognosis would emerge during treatment, high-risk patients should consider auto-SCT.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Linfoma de Células B Grandes Difuso , Humanos , Persona de Mediana Edad , Proyectos Piloto , Recurrencia Local de Neoplasia/tratamiento farmacológico , Trasplante Autólogo , Trasplante de Células Madre , Linfoma de Células B Grandes Difuso/diagnóstico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/genética , Pronóstico , Ciclofosfamida/uso terapéutico , Prednisona/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Doxorrubicina/uso terapéutico , Doxorrubicina/efectos adversos , Vincristina/uso terapéutico , ADN
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