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1.
Gastrointest Endosc ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39147103

RESUMO

BACKGROUND AND AIMS: A robust model of post-ERCP pancreatitis (PEP) risk is not currently available. We aimed to develop a machine learning-based tool for PEP risk prediction to aid in clinical decision-making related to periprocedural prophylaxis selection and post-procedural monitoring. METHODS: Feature selection, model training, and validation were performed using patient-level data from 12 randomized controlled trials. A gradient-boosted machine (GBM) model was trained to estimate PEP risk and the performance of the resulting model was evaluated using the area under the receiver operating curve (AUC) with 5-fold cross-validation. A web-based clinical decision-making tool was created, and a prospective pilot study was performed using data from ERCPs performed at the Johns Hopkins Hospital over a one-month period. RESULTS: A total of 7389 patients were included in the GBM with an 8.6% rate of PEP. The model was trained on twenty PEP risk factors and 5 prophylactic interventions (rectal non-steroidal anti-inflammatory drugs [NSAID], aggressive hydration, combined rectal NSAID and aggressive hydration, pancreatic duct [PD] stenting, and combined rectal NSAID and PD stenting). The resulting GBM model had an AUC of 0.70 (65% specificity, 65% sensitivity, 95% negative predictive value, 15% positive predictive value). A total of 135 patients were included in the prospective pilot study, resulting in an AUC of 0.74. CONCLUSIONS: This study demonstrates the feasibility and utility of a novel machine learning-based PEP risk estimation tool with high negative predictive value to aid in prophylaxis selection and identify patients at low risk who may not require extended post-procedure monitoring.

2.
J Org Chem ; 89(12): 8985-9000, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38861548

RESUMO

Ketyl radicals are synthetically versatile reactive species, but their applications have been hampered by harsh generation conditions employing highly reducing metals. Recently, the pyridine-boryl radical received wide attention as a promising organic reductant because of its mildness as well as convenience in handling. While probing the utility of the pyridine-boryl radical, our group observed facile pinacol coupling reactivity that had not been known at that time. This serendipitous finding was successfully rendered into a practical synthesis of tetraaryl-1,2-diols in up to 99% yield within 1 h. Subsequently, upon examinations of various reaction manifolds, a diastereoselective ketyl-olefin cyclization was accomplished to produce cycloalkanols such as trans-2-alkyl-1-indanols. Compared to the previous methods, the stereocontrolling ability was considerably enhanced by taking advantage of the structurally modifiable boryl group that would be present near the bond-forming site. In this full account, our synthetic efforts with the O-boryl ketyl radicals are disclosed in detail, covering the discovery, optimization, scope expansion, and mechanistic analysis, including density functional theory (DFT) calculations.

3.
Phys Chem Chem Phys ; 26(27): 18970-18982, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38953296

RESUMO

In the phase diagram of binary liquid mixtures, a miscibility gap is found with the concomitant liquid-liquid phase separation, wherein temperature is a key parameter in modulating the phase behavior. This includes critical temperatures such as the lower critical solution temperature (LCST) and upper critical solution temperature (UCST). Using a comprehensive approach including molecular dynamics (MD) simulation, graph theoretical analysis and spatial inhomogeneity measurement in an LCST-type mixture, we attempt to establish the relationship between the molecular aggregation pattern and phase behavior in TEA-water mixtures. At lower temperatures of binary liquid mixtures, TEA molecules tend to aggregate while simultaneously interacting with water forming a homogeneous solution. As the temperature increases, these TEA aggregates tend to self-associate by minimizing the interaction with water, which facilitates formation of two distinct liquid phases in the binary liquid. The spatial distribution analysis also reveals that the TEA aggregates compatible with water promote uniform distribution of water molecules, maintaining a homogeneous solution, while the water-incompatible ones generate isolation of water H-bond aggregates, leading to liquid-liquid phase separation in the binary system. This current study on temperature-induced molecular aggregation behavior is anticipated to contribute to a critical understanding of the phase behavior in binary liquid mixtures, including UCST, LCST, and reentrant phase behavior.

4.
Korean J Gastroenterol ; 83(1): 28-32, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38268166

RESUMO

Undifferentiated carcinoma of the pancreas (UPC) is a rare, aggressive pancreatic cancer subtype. In addition, there is limited data on optimal management and patients tend to present with unresectable disease. This highlights the need to explore non-surgical treatments, such as chemotherapy and radiotherapy. In 2017, a 40-year-old male was diagnosed with UPC, presenting with a 6 cm mass in the pancreas, encasing the major arteries, indicative of a locally advanced stage. Histopathology confirmed UPC with osteoclast-like giant cells. After nine cycles of modified FOLFIRINOX chemotherapy and concurrent chemoradiotherapy, treatment was stopped in 2018 because of his declining health. Remarkably, despite the cessation of treatment, by 2023, the tumor had shrunk to 3.5 cm with no metabolic activity indicated by FDG-PET/CT. This six-year survival and response to non-surgical treatment highlight potential new avenues for managing unresectable pancreatic cancer, underscoring the need for further comprehensive studies to evaluate these therapeutic strategies.


Assuntos
Adenocarcinoma , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Pancreáticas , Adulto , Humanos , Masculino , Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Sobreviventes , Sobreviventes de Câncer
5.
Nat Commun ; 15(1): 3710, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38697968

RESUMO

Whereas the conventional anti-dihalogenation of alkenes is a valuable synthetic tool with highly predictable stereospecificity, the restricted reaction mechanism makes it challenging to alter the diastereochemical course into the complementary syn-dihalogenation process. Only a few notable achievements were made recently by inverting one of the stereocenters after anti-addition using a carefully designed reagent system. Here, we report a conceptually distinctive strategy for the simultaneous double electrophilic activation of the two alkene carbons from the same side. Then, the resulting vicinal leaving groups can be displaced iteratively by nucleophilic halides to complete the syn-dihalogenation. For this purpose, thianthrenium dication is employed, and all possible combinations of chlorine and bromine are added onto internal alkenes successfully, particularly resulting in the syn-dibromination and the regiodivergent syn-bromochlorination.

6.
J Plant Physiol ; 302: 154321, 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39116627

RESUMO

Agriculture is vital for global food security, and irrigation is essential for improving crop yields. However, irrigation can pose challenges such as mineral scarcity and salt accumulation in the soil, which negatively impact plant growth and crop productivity. While numerous studies have focused on enhancing plant tolerance to high salinity, research targeting various ecotypes of Arabidopsis thaliana has been relatively limited. In this study, we aimed to identify salt-tolerant ecotypes among the diverse wild types of Arabidopsis thaliana and elucidate their characteristics at the molecular level. As a result, we found that Catania-1 (Ct-1), one of the ecotypes of Arabidopsis, exhibits greater salt tolerance compared to Col-0. Specifically, Ct-1 exhibited less damage from reactive oxygen species (ROS) than Col-0, despite not accumulating antioxidants like anthocyanins. Additionally, Ct-1 accumulated more potassium ions (K+) in its shoots and roots than Col-0 under high salinity, which is crucial for water balance and preventing dehydration. In contrast, Ct-1 plants were observed to accumulate slightly lower levels of Na+ than Col-0 in both root and shoot tissues, regardless of salt treatment. These findings suggest that Ct-1 plants achieve high salinity resistance not by extruding more Na+ than Col-0, but rather by absorbing more K+ or releasing less K+. Ct-1 exhibited higher nitrate (NO3-) levels than Col-0 under high salinity conditions, which is associated with enhanced retention of K+ ions. Additionally, genes involved in NO3- transport and uptake, such as NRT1.5 and NPF2.3, showed higher transcript levels in Ct-1 compared to Col-0 when exposed to high salinity. However, Ct-1 did not demonstrate significantly greater resistance to osmotic stress compared to Col-0. These findings suggest that enhancing plant tolerance to salt stress could involve targeting the cellular processes responsible for regulating the transport of NO3- and K+. Overall, our study sheds light on the mechanisms of plant salinity tolerance, emphasizing the importance of K+ and NO3- transport in crop improvement and food security in regions facing salinity stress.

7.
Microbiol Spectr ; 12(7): e0380923, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38809007

RESUMO

Lovebugs appeared in large numbers across a wide area in Seoul, South Korea, in June 2023. The sudden appearance of exotic insects not only discomforts people but also fosters anxiety, as their potential for pathogen transmission would be unknown. In this study, targeted next-generation sequencing (NGS) of the 16S rRNA gene V4 region was performed using iSeq 100 to screen for bacteria in lovebugs. Forty-one lovebugs (20 females and 21 males) collected in Seoul, Korea, were identified as Plecia longiforceps based on mitochondrial cytochrome oxidase subunit 1 sequencing data using PCR. We analyzed the microbiome of the lovebugs and detected 453 species of bacteria. Among all bacteria screened based on NGS, Rickettsia was detected in all samples with an average relative abundance of 80.40%, followed by Pandoraea and Ewingella. Diversity (alpha and beta) between females and males did not differ; however, only Tumebacillus showed a higher relative abundance in females. Sequencing analysis of Rickettsia using a gltA gene-specific primer by PCR showed that it had higher sequence similarity to the Rickettsia symbiont of arthropods than to the spotted fever group rickettsiae. Eleven samples in which Pandoraea was detected by iSeq 100 were confirmed by PCR and exhibited 100% sequence identity to Pandoraea oxalativorans strain DSM 23570. Consequently, the likelihood of pathogen transmission to humans is low. The applied method may play a crucial role in swiftly identifying bacterial species in the event of future outbreaks of exotic insects that may be harmful to humans.IMPORTANCELovebugs have recently emerged in large numbers in Seoul, causing major concern regarding potential health risks. By performing the next-generation sequencing of the 16S rRNA gene V4 region, we comprehensively examined the microbiome of these insects. We identified the presence of numerous bacteria, including Rickettsia and Pandoraea. Reassuringly, subsequent tests confirmed that these detected bacteria were not pathogenic. The present study addresses health concerns related to lovebugs and shows the accuracy and efficiency of our detection technique. Such methods prove invaluable for rapidly identifying bacterial species during potential outbreaks of unfamiliar insects, thereby ensuring public safety.


Assuntos
Bactérias , Microbiota , RNA Ribossômico 16S , Rickettsia , Animais , Microbiota/genética , Feminino , Masculino , RNA Ribossômico 16S/genética , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Rickettsia/genética , Rickettsia/isolamento & purificação , Rickettsia/classificação , Sequenciamento de Nucleotídeos em Larga Escala , República da Coreia , Seul , Filogenia
8.
J Clin Med ; 13(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38731143

RESUMO

Pediatric patients who undergo implant insertion into the chest wall face a high risk of implant exposure to the external environment. Five months after an 8-year-old boy underwent implantable cardioverter-defibrillator (ICD) implantation in a subcutaneous pocket in the left anterolateral chest wall to manage long QT syndrome, ICD replacement became necessary owing to exposure risk from distal and lateral thinning of the ICD pocket. Pocket rupture and exposure would increase the risk of infection; therefore, we performed ICD removal and primary pocket closure. Two weeks later, a new suprafascial pocket was created, an acellular dermal matrix (ADM) was attached to the inner wall to prevent ICD protrusion, and a new ICD was inserted. One year postoperatively, the ADM was engrafted, and no complications were observed. A thin subcutaneous layer increases the risk of ICD implantation complications. Inner wall strengthening with an ADM can help prevent pocket rupture.

9.
Heliyon ; 10(9): e30059, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38707283

RESUMO

Four species of dominant wild animals, namely, Prionailurus bengalensis euptilurus, Nyctereutes procyonoides koreensis, Hydropotes inermis argyropus, and Sus scrofa coreanus, are hosts of potential infectious agents, including helminths and protozoa. Therefore, it is necessary to analyze the infectious agents present in these wild animals to monitor and control the spread of pathogens. In the present study, fecal samples from 51 wild animals were collected from the mountains of Yangpyeong, Hoengseong, and Cheongyang in South Korea and metabarcoding of the V9 region of the 18S rRNA gene was performed to identify various parasite species that infect these wild animals. Genes from nematodes, such as Metastrongylus sp., Strongyloides spp., Ancylostoma sp., and Toxocara sp., were detected in the fecal samples from wild animals. In addition, platyhelminthes, including Spirometra sp., Echinostomatidae gen. sp., Alaria sp., Neodiplostomum sp., and Clonorchis sp., and protozoa, including Entamoeba sp., Blastocystis sp., Isospora sp., Tritrichomonas sp., Pentatrichomonas sp., and Cryptosporidium sp., were detected. In the present study, various parasites infecting wild animals were successfully identified using metabarcoding. Our technique may play a crucial role in monitoring parasites within wild animals, especially those causing zoonoses.

10.
J Med Chem ; 67(11): 9389-9405, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38787938

RESUMO

TLR7/8 agonists are versatile immune stimulators capable of treating various diseases such as viral infections, autoimmune, and cancer. Despite the structural similarity of TLR7/8, their immune stimulation mechanisms and time-course responses significantly differ. In this study, a new series of TLR7-selective agonists was synthesized utilizing the economical building block 2,6-dichloropurine. Compound 27b showed the most potent activity on hTLR7 with an EC50 of 17.53 nM and demonstrated high hTLR7 selectivity (224 folds against TLR8). 27b effectively stimulated the secretion of proinflammatory cytokines in mouse macrophages and enhanced intranasal vaccine efficacy against influenza A virus in vivo. Assessment of humoral and mucosal antibody titers confirmed that 27b elevates IgG and IgA levels, protecting against both homologous and heterologous influenza viral infections. These findings suggest that 27b is a promising candidate as a vaccine adjuvant to prevent viral infections or as a robust immunomodulator with prolonged activity for treating immune-suppressed diseases.


Assuntos
Administração Intranasal , Desenho de Fármacos , Vacinas contra Influenza , Purinas , Receptor 7 Toll-Like , Receptor 7 Toll-Like/agonistas , Animais , Camundongos , Humanos , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/administração & dosagem , Purinas/farmacologia , Purinas/química , Adjuvantes de Vacinas/farmacologia , Adjuvantes de Vacinas/química , Relação Estrutura-Atividade , Camundongos Endogâmicos BALB C , Feminino , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/imunologia , Citocinas/metabolismo , Células RAW 264.7 , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/síntese química , Adjuvantes Imunológicos/química
11.
Arch Craniofac Surg ; 24(6): 278-283, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38176762

RESUMO

The initial instance of isolated unilateral temporalis muscle hypertrophy (IUTMH) was reported in 1990. Since then, only few cases have been documented. The cause of this condition remains ambiguous; however, it is presumed to be linked to compensatory and stress-induced hypertrophy. We introduce a rare case of the diagnosis and treatment of IUTMH. A 39-year-old woman presented with a steadily enlarging pain-free swelling on the left side of her face, first noticed a month ago. Apart from a hyperthyroidism medication regimen her medical history was unremarkable. She had no history of temporomandibular joint disease, bruxism, surgery, or trauma. However, she complained of having been under substantial stress lately. Contrast-enhanced magnetic resonance imaging revealed asymmetric temporalis muscle hypertrophy. The treatment plan consisted of administering type A botulinum toxin injections into left temporalis muscle, supplemented by lifestyle changes and relaxation techniques. At a follow-up visit 9 months after the injections, the muscle contour was normalized both in physical and in radiologic examinations. While further supportive evidence is needed, it can be anticipated that cosmetic treatment with botulinum toxin, rather than surgical interventions, will become the standard treatment of IUTMH.

12.
Medicine (Baltimore) ; 102(50): e36487, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38115368

RESUMO

Using the skin of the lateral malleolus region for reconstruction of smaller areas of the palm may yield better outcomes than using the skin of the groin region. However, no previous study has provided long-term data comparing the groin and lateral malleolus regions as donor sites for full-thickness skin grafts (FTSGs) in palmar reconstruction. Therefore, this study aimed to compare the groin and lateral malleolus regions as donor sites for FTSGs in palmar reconstruction over a long-term follow-up period. The patients were classified into groin and lateral malleolus region groups (n = 15 each). Measurements were obtained at the graft site, the contralateral site corresponding to the graft site, and the donor site. A chromameter was used to measure skin color, and the Patient and Observer Scar Assessment Scale (POSAS) was used to evaluate the scar at the skin graft site. Compared to the groin region group, the lateral malleolus region group showed skin colors that were closer to the original color of the palm in terms of lightness and red/green values. Additionally, the lateral malleolus region group received better esthetic ratings in the POSAS. Our results revealed that using the lateral malleolus region for FTSGs in palmar reconstruction resulted in better outcomes than using the groin region, even over a long period.


Assuntos
Virilha , Transplante de Pele , Humanos , Transplante de Pele/métodos , Virilha/cirurgia , Cicatriz/etiologia , Pele , Mãos
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