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1.
Osteoporos Int ; 35(5): 775-783, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38240755

RESUMO

With the analysis of nationwide health claim data, treatment with the composite agent of SERMs and vitamin D reduces the risk of osteoporotic fracture and hip fracture better compared to SERMs treatment in women with osteoporosis aged ≥ 50 years. PURPOSE: This study compared the potential of the composite agent of selective estrogen receptor modulators (SERMs) and vitamin D (SERM + VitD) with that of SERMs-only for fracture prevention and mortality reduction in women aged ≥ 50 years. METHODS: The incidence of osteoporotic fracture (fractures of the vertebrae, hip, wrist, or humerus) and all-cause death after treatment with SERM + VitD and SERMs were characterized using the Korean National Health Insurance Service database 2017-2019. The participants were divided into two groups (SERM + VitD vs SERMs). After exclusion and propensity score matching, 2,885 patients from each group were included in the analysis. Fracture incidence was compared between groups. Kaplan-Meier curves were used to compare mortality. Cox proportional hazards regression analysis was used to compare the risks of fracture occurrence and mortality between the groups. RESULTS: The incidence rate (138.6/10,000 vs. 192.4/10,000 person-years), and risk of osteoporotic fractures (hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.61-0.97; p = 0.024) were lower in the SERM + VitD group than in the SERMs group. Analysis for specific fractures showed a lower hazard of hip fracture in the SERM + VitD group (HR, 0.25; 95% CI, 0.09-0.71; p = 0.009). No difference was observed between the groups regarding mortality. CONCLUSION: The risk of osteoporotic fractures, especially hip fractures, was lower in the SERM + VitD group than in the SERMs group. Therefore, the composite agent of SERMs and vitamin D can be considered as a viable option for postmenopausal women with a relatively low fracture risk.


Assuntos
Fraturas do Quadril , Osteoporose Pós-Menopausa , Osteoporose , Fraturas por Osteoporose , Humanos , Feminino , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Vitamina D/uso terapêutico , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/tratamento farmacológico , Osteoporose Pós-Menopausa/epidemiologia , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/prevenção & controle , Vitaminas
2.
Med Sci Monit ; 30: e943286, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38437191

RESUMO

BACKGROUND The modified shock index (MSI) is calculated as the ratio of heart rate (HR) to mean arterial pressure (MAP) and has been used to predict the need for massive transfusion (MT) in trauma patients. This retrospective study from a single center aimed to compare the MSI with the traditional shock index (SI) to predict the need for MT in 612 women diagnosed with primary postpartum hemorrhage (PPH) at the Emergency Department (ED) between January 2004 and August 2023. MATERIAL AND METHODS The patients were divided into the MT group and the non-MT group. The predictive power of MSI and SI was compared using the areas under the receiver operating characteristic curve (AUC). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value were calculated. RESULTS Out of 612 patients, 105 (17.2%) required MT. The MT group had higher median values than the non-MT group for MSI (1.58 vs 1.07, P<0.001) and SI (1.22 vs 0.80, P<0.001). The AUC for MSI, with a value of 0.811 (95% confidence interval [CI], 0.778-0.841), did not demonstrate a significant difference compared to the AUC for SI, which was 0.829 (95% CI, 0.797-0.858) (P=0.066). The optimal cutoff values for MSI and SI were 1.34 and 1.07, respectively. The specificity and PPV for MT were 77.1% and 40.2% for MSI, and 83.2% and 45.9% for SI. CONCLUSIONS Both MSI and SI were effective in predicting MT in patients with primary PPH. However, MSI did not demonstrate superior performance to SI.


Assuntos
Hemorragia Pós-Parto , Gravidez , Humanos , Feminino , Estudos Retrospectivos , Hemorragia Pós-Parto/terapia , Transfusão de Sangue , Serviço Hospitalar de Emergência , Frequência Cardíaca
3.
Am J Emerg Med ; 75: 53-58, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37913715

RESUMO

BACKGROUND: The predictive value of the respiratory rate­oxygenation (ROX) index for a high-flow nasal cannula (HFNC) in patients with COVID-19 with acute hypoxemic respiratory failure (AHRF) may differ from patients without COVID-19 with AHRF, but these patients have not yet been compared. We compared the diagnostic accuracy of the ROX index for HFNC failure in patients with AHRF with and without COVID-19 during acute emergency department (ED) visits. METHODS: We performed a retrospective analysis of patients with AHRF treated with an HFNC in an ED between October 2020 and April 2022. The ROX index was calculated at 1, 2, 4, 6, 12, and 24 h after HFNC placement. The primary outcome was the failure of the HFNC, which was defined as the need for subsequent intubation or death within 72 h. A receiver operating characteristic (ROC) curve was used to evaluate discriminative power of the ROX index for HFNC failure. RESULTS: Among 448 patients with AHRF treated with an HFNC in an ED, 78 (17.4%) patients were confirmed to have COVID-19. There was no significant difference in the HFNC failure rates between the non-COVID-19 and COVID-19 groups (29.5% vs. 33.3%, p = 0.498). The median ROX index was higher in the non-COVID-19 group than in the COVID-19 group at all time points. The prognostic power of the ROX index for HFNC failure as evaluated by the area under the ROC curve was generally higher in the COVID-19 group (0.73-0.83) than the non-COVID-19 group (0.62-0.75). The timing of the highest prognostic value of the ROX index for HFNC failure was at 4 h for the non-COVID-19 group, whereas in the COVID-19 group, its performance remained consistent from 1 h to 6 h. The optimal cutoff values were 6.48 and 5.79 for the non-COVID-19 and COVID-19 groups, respectively. CONCLUSIONS: The ROX index had an acceptable discriminative power for predicting HFNC failure in patients with AHRF with and without COVID-19 in the ED. However, the higher ROX index thresholds than those in previous publications involving intensive care unit (ICU) patients suggest the need for careful monitoring and establishment of a new threshold for patients admitted outside the ICU.


Assuntos
COVID-19 , Ventilação não Invasiva , Insuficiência Respiratória , Humanos , Cânula , COVID-19/terapia , Taxa Respiratória , Estudos Retrospectivos , Insuficiência Respiratória/terapia , Oxigenoterapia
4.
Plant Dis ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38173269

RESUMO

Peanut (Arachis hypogaea L.) has long been cultivated worldwide as an important crop for oil and protein production. Among the various diseases in peanut plants, wilt diseases caused by soil-borne pathogens such as Ralstonia solanacearum and Verticillium dahliae are especially destructive and substantially diminish both quantity and quality in peanut production (Kokalis-Burelle et al., 1997; Thiessen et al., 2012). In July 2022, wilt symptoms were observed in 1 to 3% of the area of peanut fields in Yeoju-si, Korea (37°23´04.0˝N; 127°33´43.0˝E). The xylem in the stems of the wilted plants was dark brown at the soil-surface, which is a representative symptom of vascular wilt pathogens (Yadeta et al. 2013). To isolate the causative pathogens, the stems exhibiting dark lesions were disinfected with 1% NaOCl for 1 min, rinsed with sterile distilled water, and placed on potato dextrose agar medium. The plates were incubated at 25℃ for 2 days, and white hyphae that grew out from the tissues were subcultured twice on V8 juice agar (V8A) medium. Among the 3 isolates, morphological characteristics of the representative strain YJ1-2 were observed under a microscope. The sporangia were terminal intercalary, filamentous, inflated lobulate, and ranging from 37.4 to 73.6 µm in diameter. The antheridia were diclinous, with clavate, elongate, and crook-necked shapes. The oogonia were mostly globose, with an average of 27.1 µm (range from 20.2 to 35.2 µm, n = 50) in diameter, and mated with one to several antheridia. Both plerotic or aplerotic oospores were observed. Overall, the morphological characteristics of the sporangia, antheridia, oogonia, and oospores indicated that YJ1-2 belongs to the genus Pythium. To genetically characterize YJ1-2, genomic DNA was extracted using cetyltrimethylammonium bromide buffer, and the internal transcribed spacer (ITS) region and cytochrome c oxidase subunit I (cox1) gene were amplified by PCR using primer sets ITS4/ITS5 and OomCoxI-Levlo/ OomCoxI-Levup, respectively (White et al., 1990; Robideau et al. 2011), sequenced, and identified using BLASTN (NCBI, National Center for Biotechnology Information). The ITS sequence (NCBI Acc. No. OR125595) of YJ1-2 has 99% similarity with that of P. myriotylum isolate PY39 (NCBI Acc. No. KX671096). A neighbor-joining phylogenetic tree was constructed from aligned cox1 sequence (NCBI Acc. No. OR224334) of the 10 Pythium species strains including YJ1-2 by CLUSTALW method was used as an outgroup. The YJ1-2 was most closely related to P. myriotylum isolate PM30 (NCBI Acc. No. MT823167). To substantiate the pathogenicity of YJ1-2, the crown roots of peanut plants grown in pots for 4 weeks were wounded using a sterile tweezer, and the mycelial plugs of YJ1-2 cultured for 5 days on V8A were inoculated on the wounds. The inoculated plants were cultivated in a growth chamber at 30℃ and 70% relative humidity with a 12-h photoperiod. The infected peanut plants exhibited wilt symptoms 11 days after inoculation, consistent with the initial observation, while uninoculated plants remained healthy. To satisfy Koch's postulates, white mycelia were re-isolated from the stems of inoculated plants and axenically cultured in V8A. The morphologies and ITS sequences of the re-isolates were consistent with those of YJ1-2. P. myriotylum has been reported as a causal pathogen of peanut pod rot in the United States and China. However, to the best of our knowledge, this is the first report of wilt disease in peanut plants caused by P. myriotylum in Korea. To prevent the incidence of wilt disease, we will continue our investigations to develop control strategies, including the selection of appropriate agrochemicals.

5.
Int J Mol Sci ; 25(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38892065

RESUMO

Hormone receptor-positive and HER2-negative breast cancer (HR+/HER2-BC) is the most common type with a favorable prognosis under endocrine therapy. However, it still demonstrates unpredictable progression and recurrences influenced by high tumoral diversity and microenvironmental status. To address these heterogeneous molecular characteristics of HR+/HER2-BC, we aimed to simultaneously characterize its transcriptomic landscape and genetic architecture at the same resolution. Using advanced single-cell RNA and DNA sequencing techniques together, we defined four distinct tumor subtypes. Notably, the migratory tumor subtype was closely linked to genomic alterations of EGFR, related to the tumor-promoting behavior of IL6-positive inflammatory tumor-associated fibroblast, and contributing to poor prognosis. Our study comprehensively utilizes integrated analysis to uncover the complex dynamics of this breast cancer subtype, highlighting the pivotal role of the migratory tumor subtype in influencing surrounding cells. This sheds light on potential therapeutic targets by offering enhanced insights for HR+/HER2-BC treatment.


Assuntos
Neoplasias da Mama , Fibroblastos Associados a Câncer , Movimento Celular , Receptor ErbB-2 , Humanos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Feminino , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Receptor ErbB-2/metabolismo , Receptor ErbB-2/genética , Regulação Neoplásica da Expressão Gênica , Receptores de Estrogênio/metabolismo , Receptores de Estrogênio/genética , Microambiente Tumoral , Linhagem Celular Tumoral , Receptores de Progesterona/metabolismo , Receptores de Progesterona/genética , Prognóstico , Receptores ErbB/metabolismo , Receptores ErbB/genética , Análise de Célula Única
6.
J Cell Sci ; 134(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34096606

RESUMO

About 70% of breast cancers overexpress estrogen receptor α (ERα, encoded by ESR1). Tamoxifen, a competitive inhibitor of estrogen that binds to ER, has been widely used as a treatment for ER-positive breast cancer. However, 20-30% of breast cancer is resistant to tamoxifen treatment. The mechanisms underlying tamoxifen resistance remain elusive. We found that Yes-associated protein (YAP; also known as YAP1), connective tissue growth factor (CTGF; also known as CCN2) and cysteine-rich angiogenic inducer 61 (Cyr61; also known as CCN1) are overexpressed, while ERα is downregulated in tamoxifen-resistant breast cancer. Inhibition of YAP, CTGF and Cyr61 restored ERα expression and increased sensitivity to tamoxifen. Overexpression of YAP, CTGF, and Cyr61 led to downregulation of ERα and conferred resistance to tamoxifen in ER-positive breast cancer cells. Mechanistically, CTGF and Cyr61 downregulated ERα expression at the transcriptional level by directly binding to the regulatory regions of the ERα-encoding gene, leading to increased tamoxifen resistance. Also, CTGF induced Glut3 (also known as SLC2A3) expression, leading to increased glycolysis, which enhanced cell proliferation and migration in tamoxifen-resistant cells. Together, these results demonstrate a novel role of YAP, CTGF and Cyr61 in tamoxifen resistance and provide a molecular basis for their function in tamoxifen-resistant breast cancer.


Assuntos
Neoplasias da Mama , Tamoxifeno , Proteínas Adaptadoras de Transdução de Sinal , Mama/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Fator de Crescimento do Tecido Conjuntivo/genética , Proteína Rica em Cisteína 61 , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Tamoxifeno/farmacologia , Fatores de Transcrição , Proteínas de Sinalização YAP
7.
Inorg Chem ; 62(37): 15084-15093, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37667823

RESUMO

We report the synthesis and characterization of various compounds containing the 1,7,9-hydroxylated closo-dodecahydrododecaborate (B12H9(OH)32-) cluster motif. Specifically, we show how the parent compound can be synthesized on the multigram scale and further perhalogenated, leading to a new class of vertex-differentiated weakly coordinating anions. We show that a postmodification of the hydroxyl groups by alkylation affords further opportunities for tailoring these anions' stability, steric bulk, and solubility properties. The resulting dodecaborate-based salts were subjected to a full thermal and electrochemical stability evaluation, showing that many of these anions maintain thermal stability up to 500 °C and feature no redox activity below ∼1 V vs Fc/Fc+. Mixed hydroxylated/halogenated clusters show enhanced solubility compared to their purely halogenated analogs and retain weakly coordinating properties in the solid state, as demonstrated by ionic conductivity measurements of their Li+ salts.

8.
Sensors (Basel) ; 23(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37430819

RESUMO

Pedestrian tracking is a challenging task in the area of visual object tracking research and it is a vital component of various vision-based applications such as surveillance systems, human-following robots, and autonomous vehicles. In this paper, we proposed a single pedestrian tracking (SPT) framework for identifying each instance of a person across all video frames through a tracking-by-detection paradigm that combines deep learning and metric learning-based approaches. The SPT framework comprises three main modules: detection, re-identification, and tracking. Our contribution is a significant improvement in the results by designing two compact metric learning-based models using Siamese architecture in the pedestrian re-identification module and combining one of the most robust re-identification models for data associated with the pedestrian detector in the tracking module. We carried out several analyses to evaluate the performance of our SPT framework for single pedestrian tracking in the videos. The results of the re-identification module validate that our two proposed re-identification models surpass existing state-of-the-art models with increased accuracies of 79.2% and 83.9% on the large dataset and 92% and 96% on the small dataset. Moreover, the proposed SPT tracker, along with six state-of-the-art (SOTA) tracking models, has been tested on various indoor and outdoor video sequences. A qualitative analysis considering six major environmental factors verifies the effectiveness of our SPT tracker under illumination changes, appearance variations due to pose changes, changes in target position, and partial occlusions. In addition, quantitative analysis based on experimental results also demonstrates that our proposed SPT tracker outperforms the GOTURN, CSRT, KCF, and SiamFC trackers with a success rate of 79.7% while beating the DiamSiamRPN, SiamFC, CSRT, GOTURN, and SiamMask trackers with an average of 18 tracking frames per second.

9.
Int J Mol Sci ; 24(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36674955

RESUMO

Basal-like breast cancer (BLBC) has a clinically aggressive nature. It is prevalent in young women and is known to often relapse rapidly. To date, the molecular mechanisms regarding the aggressiveness of BLBC have not been fully understood. In the present study, mechanisms of aggressiveness of BLBC involving EGFR and/or HER2 expression and interactions between tumor and tumor-associated macrophages (TAMs) were explored. The prognosis of breast cancer patients who underwent surgery at Samsung Medical Center was analyzed. It was found that the co-expression of EGFR and HER2 was associated with a worse prognosis. Therefore, we generated EGFR-positive BLBC cells with stable HER2 overexpression and analyzed the profile of secretory cytokines. Chemokine (C-C motif) ligand 2 (CCL2) expression was increased in HER2-overexpressed BLBC cells. Recombinant human CCL2 treatment augmented the motility of TAMs. In addition, the conditioned culture media of HER2-overexpressed BLBC cells increased the motility of TAMs. Furthermore, activation of TAMs by CCL2 or the conditioned culture media of HER2-overexpressed cells resulted in the production of pro-inflammatory cytokines, such as IL-8 and IL-1ß. These observations reveal that CCL2 derived from EGFR and HER2 co-expressed BLBC cells can lead to increased TAM recruitment and the induction of IL-8 and IL-1ß from recruited TAMs, triggering the tumorigenesis of breast cancer with the expression of both EGFR and HER2. Our findings demonstrate that EGFR+ and HER2+ BLBC aggressiveness is partially mediated through the interaction between BLBC and TAMs recruited by CCL2.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/metabolismo , Macrófagos Associados a Tumor/metabolismo , Meios de Cultivo Condicionados , Interleucina-8 , Recidiva Local de Neoplasia , Citocinas , Receptores ErbB/genética , Linhagem Celular Tumoral
10.
Int J Mol Sci ; 24(21)2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37958960

RESUMO

In present study, icariin (ICA)/tannic acid (TA)-nanodiamonds (NDs) were prepared as follows. ICA was anchored to ND surfaces with absorbed TA (ICA/TA-NDs) and we evaluated their in vitro anti-inflammatory effects on lipopolysaccharide (LPS)-activated macrophages and in vivo cartilage protective effects on a rat model of monosodium iodoacetate (MIA)-induced osteoarthritis (OA). The ICA/TA-NDs showed prolonged release of ICA from the NDs for up to 28 days in a sustained manner. ICA/TA-NDs inhibited the mRNA levels of pro-inflammatory elements, including matrix metalloproteinases-3 (MMP-3), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α), and increased the mRNA levels of anti-inflammatory factors (i.e., IL-4 and IL-10) in LPS-activated RAW 264.7 macrophages. Animal studies exhibited that intra-articular injection of ICA/TA-NDs notably suppressed levels of IL-6, MMP-3, and TNF-α and induced level of IL-10 in serum of MIA-induced OA rat models in a dose-dependent manner. Furthermore, these noticeable anti-inflammatory effects of ICA/TA-NDs remarkably contributed to the protection of the progression of MIA-induced OA and cartilage degradation, as exhibited by micro-computed tomography (micro-CT), gross findings, and histological investigations. Accordingly, in vitro and in vivo findings suggest that the prolonged ICA delivery of ICA/TA-NDs possesses an excellent latent to improve inflammation as well as defend against cartilage disorder in OA.


Assuntos
Cartilagem Articular , Nanodiamantes , Osteoartrite , Ratos , Animais , Interleucina-10/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Microtomografia por Raio-X , Cartilagem Articular/metabolismo , Osteoartrite/metabolismo , Anti-Inflamatórios/farmacologia , Ácido Iodoacético/efeitos adversos , RNA Mensageiro/metabolismo , Modelos Animais de Doenças
11.
Int J Mol Sci ; 24(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36835253

RESUMO

Inflammatory environments provide vital biochemical stimuli (i.e., oxidative stress, pH, and enzymes) for triggered drug delivery in a controlled manner. Inflammation alters the local pH within the affected tissues. As a result, pH-sensitive nanomaterials can be used to effectively target drugs to the site of inflammation. Herein, we designed pH-sensitive nanoparticles in which resveratrol (an anti-inflammatory and antioxidant compound (RES)) and urocanic acid (UA) were complexed with a pH-sensitive moiety using an emulsion method. These RES-UA NPs were characterized by transmission electron microscopy, dynamic light scattering, zeta potential, and FT-IR spectroscopy. The anti-inflammatory and antioxidant activities of the RES-UA NPs were assessed in RAW 264.7 macrophages. The NPs were circular in shape and ranged in size from 106 to 180 nm. The RES-UA NPs suppressed the mRNA expression of the pro-inflammatory molecules inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages in a concentration-dependent manner. Incubation of LPS-stimulated macrophages with RES-UA NPs reduced the generation of reactive oxygen species (ROS) in a concentration-dependent manner. These results suggest that pH-responsive RES-UA NPs can be used to decrease ROS generation and inflammation.


Assuntos
Anti-Inflamatórios , Antioxidantes , Nanopartículas , Resveratrol , Ácido Urocânico , Humanos , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Ciclo-Oxigenase 2/metabolismo , Concentração de Íons de Hidrogênio , Inflamação/metabolismo , Lipopolissacarídeos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Resveratrol/química , Resveratrol/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Fator de Necrose Tumoral alfa/metabolismo , Ácido Urocânico/química , Ácido Urocânico/farmacologia
12.
J Am Chem Soc ; 144(45): 20661-20671, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36326751

RESUMO

The synthesis of a piano-stool ruthenium hydride, [(η5-C5Me5)Ru(PmIm)H] (PmIm = (N-(1,3,5-trimethylphenyl)-1-(pyrimidin-2-yl)ethan-1-imine), for the dual purpose of catalytic dihydrogen activation and subsequent hydrogen atom transfer for the formation of weak chemical bonds is described. The introduction of a neutral, potentially redox-active PmIm supporting ligand was designed to eliminate the possibility of deleterious C(sp2)-H reductive coupling and elimination that has been identified as a deactivation pathway with related rhodium and iridium catalysts. Treatment of [(η5-C5Me5)RuCl2]n with one equivalent PmIm ligand in the presence of zinc and sodium methoxide resulted in the isolation of the diruthenium complex, [(η5-C5Me5)Ru(PmIm)]2, arising from the C-C bond formation between two PmIm chelates. Addition of H2 to the ruthenium dimer under both thermal and blue light irradiation conditions furnished the targeted hydride, [(η5-C5Me5)Ru(PmIm)H], which has a relatively weak DFT-calculated Ru-H bond dissociation free energy (BDFE) of 47.9 kcal/mol. Addition of TEMPO to [(η5-C5Me5)Ru(PmIm)H] generated the 17-electron metalloradical, [(η5-C5Me5)Ru(PmIm)], which was characterized by EPR spectroscopy. The C-C bond forming process was reversible as the irradiation of [(η5-C5Me5)Ru(PmIm)]2 generated [(η5-C5Me5)Ru(PmIm)H] and a piano-stool ruthenium complex containing an enamide ligand derived from H-atom abstraction from the PmIm chelate. Equilibration studies were used to establish an experimental estimate of the effective Ru-H BDFE, and a value of 50.8 kcal/mol was obtained, in agreement with the observed loss of H2 and the DFT-computed value. The ruthenium hydride was an effective catalyst for the thermal catalytic hydrogenation of TEMPO, acridine, and a cobalt-imido complex and for the selective reduction of azobenzene to diphenylhydrazine, highlighting the role of this complex in catalytic weak bond formation using H2 as the stoichiometric reductant.


Assuntos
Compostos Organometálicos , Rutênio , Rutênio/química , Ligantes , Iminas , Compostos Organometálicos/química , Oxirredução , Hidrogênio/química , Pirimidinas
13.
Opt Express ; 30(4): 5473-5485, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35209509

RESUMO

When acquiring a terahertz signal from a time-domain spectroscopy system, the signal is degraded by measurement noise and the information embedded in the signal is distorted. For high-performing terahertz applications, this study proposes a method for enhancing such a noise-degraded terahertz signal using machine learning that is applied to the raw signal after acquisition. The proposed method learns a function that maps the degraded signal to the clean signal using a WaveNet-based neural network that performs multiple layers of dilated convolutions. It also includes learnable pre- and post-processing modules that automatically transform the time domain where the enhancement process operates. When training the neural network, a data augmentation scheme is adopted to tackle the issue of insufficient training data. The comparative evaluation confirms that the proposed method outperforms other baseline neural networks in terms of signal-to-noise ratio. The proposed method also performs significantly better than the averaging of multiple signals, thereby facilitating the procurement of an enhanced signal without increasing the measurement time.

14.
Curr HIV/AIDS Rep ; 19(6): 600-609, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36156183

RESUMO

PURPOSE OF REVIEW: This review summarizes technology-based interventions for HIV in low- and middle-income countries (LMICs). We highlight potential benefits and challenges to using telehealth in LMICs and propose areas for future study. RECENT FINDINGS: We identified several models for using telehealth to expand HIV health care access in LMICs, including telemedicine visits for pre-exposure prophylaxis (PrEP) and antiretroviral therapy (ART) services, telementoring programs for providers, and virtual peer-support groups. Emerging data support the acceptability and feasibility of these strategies. However, further investigations are needed to determine whether these models are scalable and sustainable in the face of barriers related to cost, infrastructure, and regulatory approval. HIV telehealth interventions may be a valuable approach to addressing gaps along the HIV care cascade in LMICs. Future studies should focus on strategies for expanding existing programs to scale and for assessing long-term clinical outcomes.


Assuntos
Infecções por HIV , Profilaxia Pré-Exposição , Telemedicina , Humanos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Países em Desenvolvimento , Antirretrovirais/uso terapêutico
15.
Chem Rev ; 120(12): 5637-5681, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32458682

RESUMO

The functionalization of coordinated dinitrogen to form nitrogen-element bonds en route to nitrogen-containing molecules is a long-standing challenge in chemical synthesis. The strong triple bond and the nonpolarity of the N2 molecule pose thermodynamic and kinetic challenges for promoting reactivity. While heterogeneous, homogeneous, and biological catalysts are all known for catalytic nitrogen fixation to ammonia, the catalytic synthesis of more complicated nitrogen-containing organic molecules has far less precedent. The example of silyl radical additions to coordinated nitrogen to form silylamines stands as the lone example of a catalytic reaction involving N2 to form a product other than ammonia. This Review surveys the field of molecular transition metal complexes as well as recent boron examples for the formation of nitrogen-element bonds. Emphasis is placed on the coordination and activation modes of N2 in the various metal compounds from across the transition series and how these structures can rationally inform reactivity studies. Over the past few decades, the field has evolved from the addition of carbon electrophiles in a manner similar to that of protonation reactions to more organometallic-inspired reactivity, including insertions, 1,2-additions, and cycloadditions. Various N-C, N-Si, and N-B bond-forming reactions have been discovered, highlighting that the challenge for catalytic chemistry is not in the reactivity of coordinated dinitrogen but rather removal of the functionalized ligand from the coordination sphere of the metal.

16.
Nanotechnology ; 33(16)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-34952534

RESUMO

A residue-free transfer method for graphene is proposed in this study, especially for the fabrication of suspended structures. Using perforated polymer templates, graphene can be precisely transferred onto the specific position in the perforated target SiO2/Si substrates without the need for polymer removal and the subsequent thermal annealing process. The surface of the transferred graphene by the proposed method was analyzed and corroborated via Raman spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy. The results of these analyses suggest that the graphene surface has no polymeric residues resulting from the transfer process. The proposed method provides a powerful approach for the transfer of 2D materials and it enables the exploitation of their suspended structures for device applications as well as the physical characterizations without worry on the effect of contaminants.

17.
Crit Care ; 26(1): 378, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36476543

RESUMO

BACKGROUND: Previously conducted physician-centered trials on the usefulness of vasopressin have yielded negative results; thus, patient-oriented trials have been warranted. We hypothesize that Augmented-Medication CardioPulmonary Resuscitation could be helpful for selected patients with out-of-hospital cardiac arrest (OHCA). METHODS: This is a double-blind, single-center, randomized, placebo-controlled trial conducted in the emergency department in a tertiary, university-affiliated hospital in Seoul, Korea. A total of 148 adults with non-traumatic OHCA who had initial diastolic blood pressure (DBP) < 20 mm Hg via invasive arterial monitoring during the early cardiac compression period were randomly assigned to two groups. Patients received a dose of 40 IU of vasopressin or placebo with initial epinephrine. The primary endpoint was a sustained return of spontaneous circulation. Secondary endpoints were survival discharge, and neurologic outcomes at discharge. RESULTS: Of the 180 included patients, 32 were excluded, and 148 were enrolled in the trial. A sustained return of spontaneous circulation was achieved by 27 patients (36.5%) in the vasopressin group and 24 patients (32.4%) in the control group (risk difference, 4.1%; P = .60). Survival discharge and good neurologic outcomes did not differ between groups. The trial group had significantly higher median DBPs during resuscitation than the control group (16.0 vs. 14.5 mm Hg, P < 0.01). There was no difference in end-tidal carbon dioxide, acidosis, and lactate levels at baseline, 10 min, and end-time. CONCLUSION: Among patients with refractory vasodilatory shock in OHCA, administration of vasopressin, compared with placebo, did not significantly increase the likelihood of return of spontaneous circulation.


Assuntos
Parada Cardíaca Extra-Hospitalar , Humanos , Parada Cardíaca Extra-Hospitalar/tratamento farmacológico , Projetos Piloto , Vasopressinas/uso terapêutico
18.
J Intensive Care Med ; 37(6): 721-727, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34105409

RESUMO

BACKGROUND: Despite thrombocytopenia, patients with sepsis often experience hypercoagulability. However, limited information is available on the prevalence and effect of hypercoagulability in patients with sepsis-induced thrombocytopenia. Hence, we evaluated the prevalence of hypercoagulability and the association between hypercoagulability and clinical outcomes in septic shock patients with thrombocytopenia. METHODS: Thromboelastography (TEG) was performed prospectively in 1294 patients with septic shock at the emergency department (ED) between January 2016 and December 2019. After excluding 405 patients who did not require resuscitation, refused enrollment, or developed septic shock after ED presentation, 889 patients were included. We defined thrombocytopenia as an admission platelet count lower than 150,000/µl according to SOFA score. We defined hypocoagulability and hypercoagulability as coagulation index (CI)< -3 and >3 on TEG, respectively. RESULTS: Of the 889 septic shock patients (mean age 65.6 ± 12.7 years, 58.6% male), 473 (53.2%) had thrombocytopenia. Eighty-five (18.0%) patients showed hypercoagulable TEG and73 (15.4%) patients showed hypocoagulable TEG. The hypercoagulable TEG group had a significantly higher fibrinogen level and a lower 28-day mortality rate than the normal and hypocoagulable TEG groups (518 vs. 347 and 315 mg/dL; 7.1% vs. 21.1% and 36.8%, P < 0.01, respectively). In multivariate analysis, hypercoagulable TEG was associated with a decreased mortality rate (odds ratio: 0.395; 95% confidence interval, 0.162-0.965). CONCLUSIONS: In septic shock patients with thrombocytopenia, hypercoagulability was not uncommon. TEG can quickly distinguish the hypercoagulability and hypocoagulability states and serve as a valuable tool for evaluating the degree and risk in septic shock patients with thrombocytopenia.


Assuntos
Anemia , Sepse , Choque Séptico , Trombocitopenia , Trombofilia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sepse/complicações , Choque Séptico/complicações , Tromboelastografia , Trombocitopenia/complicações , Trombofilia/complicações
19.
Am J Emerg Med ; 61: 74-80, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36057212

RESUMO

BACKGROUND: Anaphylaxis is a potentially life-threatening condition that occurs in the emergency department (ED). Although anaphylaxis is rapidly recognized and treated in the hospital compared with that in the community, in some cases, it does not respond to proper management. OBJECTIVE: The aim of this study is to describe our experience of cases of refractory anaphylaxis leading to cardiac arrest in hospital, to review their characteristics compared with those seen in the community, and to discuss the best management practices for anaphylaxis-induced cardiac arrest with a literature review. METHODS: We reviewed the medical records of patients referred to the ED with possible in-hospital anaphylaxis between January 2017 and May 2021. According to the anaphylaxis protocol, epinephrine, corticosteroid, and antihistamine were administered immediately on-site at our institution before the study period. Refractory anaphylaxis was defined as the development of anaphylaxis-induced cardiac arrest even after following the anaphylaxis protocol. RESULTS: A total of 246 cases were evaluated for possible anaphylaxis, with 236 cases meeting the criteria for a diagnosis of anaphylaxis. Among them, 178 patients showed the signs and symptoms of shock, and cardiac arrest occurred in 6 patients (2.5%). Of the six patients, three had a return of spontaneous circulation before admission to the ED, while two died due to refractory cardiac arrest despite resuscitation in the ED. Following post-cardiac arrest care, including temperature management, one patient who received extracorporeal cardiopulmonary resuscitation survived neurologically intact. CONCLUSION: We present our case series to highlight the risk of developing refractory anaphylaxis with subsequent in-hospital cardiac arrest. Patients may progress to cardiac arrest within minutes despite prompt recognition and management. If patients present with potentially fatal symptoms, a more aggressive approach, including intravenous adrenaline infusion, should be taken.


Assuntos
Anafilaxia , Reanimação Cardiopulmonar , Parada Cardíaca , Humanos , Anafilaxia/complicações , Anafilaxia/terapia , Parada Cardíaca/etiologia , Parada Cardíaca/terapia , Parada Cardíaca/diagnóstico , Reanimação Cardiopulmonar/métodos , Epinefrina/uso terapêutico , Antagonistas dos Receptores Histamínicos
20.
J Korean Med Sci ; 37(21): e169, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35638196

RESUMO

With the global spread of severe acute respiratory syndrome coronavirus 2, several vaccines were developed; messenger RNA (mRNA) vaccines have recently been widely used worldwide. However, the incidence of myocarditis following mRNA vaccination is increasing; although the cause of myocarditis has not yet been clearly identified, it is presumed to be caused by a problem in the innate immune system. Immune-mediated thrombocytopenia (ITP) after vaccination is rare but has been reported and is also assumed to occur by the same mechanism. We report the first case of simultaneous myocarditis and ITP after mRNA vaccination. A 38-year-old woman presented with chest pain, mild dyspnea, and sweating after vaccination with mRNA-1273 vaccine (Moderna) 4 days prior to admission. Upon admission to the emergency department, cardiac enzymes were elevated; blood test performed 5 months ago showed normal platelet count, but severe thrombocytopenia was observed upon admission. After administration of intravenous immunoglobulin, the platelet count improved; subsequently, myocarditis was observed on endomyocardial biopsy. Thus, myocarditis and ITP were judged to have occurred simultaneously due to the expression of the innate immune system markers after mRNA vaccination. The patient was discharged on day 6 of admission.


Assuntos
COVID-19 , Miocardite , Púrpura Trombocitopênica Idiopática , Trombocitopenia , Vacinas , Vacina de mRNA-1273 contra 2019-nCoV , Adulto , Vacinas contra COVID-19/efeitos adversos , Feminino , Humanos , Miocardite/complicações , Miocardite/etiologia , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/etiologia , RNA Mensageiro/genética , Trombocitopenia/complicações , Trombocitopenia/etiologia , Vacinação/efeitos adversos
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