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81.
Renal impairment (RI) is common in patients with multiple myeloma (MM) and new therapies that can improve renal function are needed. The phase III IKEMA study (clinicaltrials gov. Identifier: NCT03275285) investigated isatuximab (Isa) with carfilzomib and dexamethasone (Kd) versus Kd in relapsed MM. This subgroup analysis examined results from patients with RI, defined as estimated glomerular filtration rate <60 mL/min/1.73 m². Addition of Isa prolonged progression-free survival (PFS) in patients with RI (hazard ratio: 0.27; 95% confidence interval [CI]: 0.11–0.66; median PFS not reached for Isa-Kd versus 13.4 months for Kd [20.8-month follow-up]). Complete renal responses occurred more frequently with Isa-Kd (52.0%) versus Kd (30.8%) and were durable in 32.0% versus 7.7% of patients, respectively. Treatment exposure was longer with Isa-Kd, with median number of started cycles and median duration of exposure of 20 versus 9 cycles and 81.0 versus 35.7 weeks for Isa-Kd versus Kd, respectively. Among patients with RI, the incidence of patients with grade ≥3 treatment-emergent adverse events was similar between the two arms (79.1% in Isa-Kd vs. 77.8% in Kd). In summary, the addition of Isa to Kd improved clinical outcomes with a manageable safety profile in patients with RI, consistent with the benefit observed in the overall IKEMA study population.  相似文献   
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Four new prenylated isoflavonoids, vogelins D-G (1-4), were isolated from the CH2Cl2 extract of Erythrina vogelii root bark in addition to the known compounds isolupalbigenin (5), ficuisoflavone (6), ulexone (7), isochandalon (8), and isoderrone (9). The structures 1-4 were elucidated by spectroscopic and chemical methods. The absolute configuration of compound 1 was determined on the basis of its CD spectrum. Possible biogenetic relationships among the E. vogelii isoflavonoids are briefly discussed.  相似文献   
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To tune and test the generalizability of a deep learning-based model for assessment of COVID-19 lung disease severity on chest radiographs (CXRs) from different patient populations.A published convolutional Siamese neural network-based model previously trained on hospitalized patients with COVID-19 was tuned using 250 outpatient CXRs. This model produces a quantitative measure of COVID-19 lung disease severity (pulmonary x-ray severity (PXS) score). The model was evaluated on CXRs from 4 test sets, including 3 from the United States (patients hospitalized at an academic medical center (N = 154), patients hospitalized at a community hospital (N = 113), and outpatients (N = 108)) and 1 from Brazil (patients at an academic medical center emergency department (N = 303)). Radiologists from both countries independently assigned reference standard CXR severity scores, which were correlated with the PXS scores as a measure of model performance (Pearson R). The Uniform Manifold Approximation and Projection (UMAP) technique was used to visualize the neural network results.Tuning the deep learning model with outpatient data showed high model performance in 2 United States hospitalized patient datasets (R = 0.88 and R = 0.90, compared to baseline R = 0.86). Model performance was similar, though slightly lower, when tested on the United States outpatient and Brazil emergency department datasets (R = 0.86 and R = 0.85, respectively). UMAP showed that the model learned disease severity information that generalized across test sets.A deep learning model that extracts a COVID-19 severity score on CXRs showed generalizable performance across multiple populations from 2 continents, including outpatients and hospitalized patients.  相似文献   
86.

Aim of the study

Ilex paraguariensis St. Hilaire (Aquifoliaceae) is a plant widely cultivated in South America that is used to prepare a tea-like beverage with a reputation to improve cognitive function, a response that has been attributed to the constituents of the leaves, especially caffeine. Our previous study indicated that the hydroalcoholic extract of Ilex paraguariensis presents an antiparkinsonian profile in reserpine- and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP)-treated rodents.

Materials and methods

In the present study, the effects of the hydroalcoholic extract of Ilex paraguariensis on the short- and long-term learning and memory of rats were assessed with the social recognition, Morris water maze, and step-down inhibitory avoidance tasks.

Results

A preliminary HPLC fingerprint of the plant extract confirmed the presence of caffeine (the major compound), rutin and kaemperol, and revealed the absence of detectable concentrations of caffeic acid, quercetin and ursolic acid. Acute pre-training intraperitoneal (i.p.) or oral administration of the extract of Ilex paraguariensis improved the short-term social memory in a specific manner as well as facilitated the step-down inhibitory avoidance short-term memory evaluated 1.5 h after training. Moreover, a synergistic response was observed following the co-administration of ‘non-effective’ doses of caffeine and Ilex paraguariensis in the social memory. In contrast, pre-training administration of hydroalcoholic extract of Ilex paraguariensis did not alter the step-down inhibitory avoidance long-term memory evaluated 24 h after training, while the highest dose tested (250 mg/kg, i.p.) disrupted the animals’ performance in a cued version of the Morris water maze.

Conclusion

These results partly substantiate the traditional use of mate tea for improvement of cognition indicating that acute administration of hydroalcoholic extract of Ilex paraguariensis differentially modulates short- and long-term learning and memory in rats probably through its antagonist's action on adenosine receptors.  相似文献   
87.
ObjectivesUterine adenosquamous carcinoma (ASC) is an uncommon, yet, one of the most aggressive cervical cancer subtype. The successful treatment of some tumors, such as gastrointestinal stromal tumors (GISTs), by anti-KIT inhibitors fosters the study of this receptor tyrosine kinase in other malignancies. In the present study, we intended to molecularly characterize KIT in ASC.MethodsIn a series of 30 cases, we studied KIT (CD117), KIT phosphorylated / activated form, as well as KIT ligand, stem cell factor (SCF), by immunohistochemistry. We further screened for KIT hotspot mutations (exon 9, 11, 13 and 17) by PCR-SSCP and for KIT gene amplification by Quantitative real-time PCR in CD117 positive cases.ResultsWe observed CD117 expression in ~ 13% of cases, with ~ 7% co-expressing SCF, which resulted in KIT phosphorylation/activation. No KIT activating mutations or gene amplification were found, despite the presence of 4q aneuploidy in one case.ConclusionsThis is the first study assessing KIT activation and molecular alterations in a large series of rare ASC. Our findings showed the absence of KIT molecular alterations and suggested the presence of KIT activation in a small proportion of cases through KIT/SCF co-expression.  相似文献   
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OBJECTIVE: We sought to determine the significance of lymphatic vessel density (LVD) in pre-malignant lesions and carcinomas of the uterine cervix and to evaluate the prognostic value of lymphatic invasion and D2-40 positivity in tumor cells in the three histological types of invasive lesions. The correlation of LVD, lymphatic invasion and D2-40 positivity in tumor cells with EGFR and COX-2 expressions was also evaluated. METHODS: We studied 50 cervicitis, 50 low-grade squamous intraepithelial lesions (LSIL) (CIN1), 51 high-grade squamous intraepithelial lesions (HSIL) (CIN2/CIN3), 49 invasive squamous cells carcinomas (SCC), 43 adenocarcinomas (AC) and 30 adenosquamous cells carcinomas (ASC). The immunoreaction assay was performed using the monoclonal antibody D2-40. RESULTS: Significant differences in LVD were found among all categories of pre-invasive and invasive lesions (p=0.001 and p<0.001, respectively). LVD in invasive lesions was significantly greater than in pre-invasive lesions (p<0.001) and no significant association was found between LVD in invasive lesions and both lymph node invasion and/or metastasis. D2-40 positivity in tumor cells was associated with a better prognosis in ASC cases. EGFR and COX-2 expressions in invasive lesions were not associated with LVD; however, they correlated with both lymphatic invasion and D2-40 positivity in tumor cells. CONCLUSIONS: Lymphatic neovascularization begins early in intraepithelial lesions and continues to increase towards malignancy. Both lymphatic invasion and decrease in D2-40 expression in tumor cells appear to have a prognostic value.  相似文献   
90.
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