273 research outputs found
Frequency dependence of viscous and viscoelastic dissipation in coated micro-cantilevers from noise measurement
We measure the mechanical thermal noise of soft silicon atomic force
microscopy cantilevers. Using an interferometric setup, we have a resolution
down to 1E-14 m/rtHz on a wide spectral range (3 Hz to 1E5 Hz). The low
frequency behavior depends dramatically on the presence of a reflective
coating: almost flat spectrums for uncoated cantilevers versus 1/f like trend
for coated ones. The addition of a viscoelastic term in models of the
mechanical system can account for this observation. Use of Kramers-Kronig
relations validate this approach with a complete determination of the response
of the cantilever: a power law with a small coefficient is found for the
frequency dependence of viscoelasticity due to the coating, whereas the viscous
damping due to the surrounding atmosphere is accurately described by the Sader
model
Global features of sea-level pressure distribution in April and July associated with contrasting situations of Indian summer monsoon
Gastroenteropancreatic High-Grade Neuroendocrine Neoplasms: Histology and Molecular Analysis, Two Sides of the Same Coin
Background: In gastroenteropancreatic (GEP) high-grade neuroendocrine neoplasms (H-NENs), Ki-67 threshold of 55% defines three prognosis subclasses: neuroendocrine tumor (NET) G3, neuroendocrine carcinoma (NEC) <55%, and NEC ≥55%. We investigated whether the molecular profiling of H-NENs differs among these subcategories and evaluated potential therapeutic targets, including PD-L1. Methods: In GEP-NEN patients, we evaluated: (i) 55% threshold for Ki-67 labeling index for further stratifying NEC and (ii) immunoreactivity and gene mutations by immunohistochemistry and targeted next-generation sequencing (T-NGS). Results: Fifteen NETs G3 and 39 NECs were identified. Ki-67 labeling index was <55% in 9 NECs and ≥55% in 30 NECs. Gene mutations by NGS (TP53, 32.9%; KRAS, 5.5%; BRAF, 4.1%) were detected in 46.6% NENs, significantly enriched in NEC ≥55% (76.7%) compared to NEC <55% (55.6%) or NET (20.0%). PD-L1 staining in tumor-infiltrating lymphocytes was observed in NEC ≥55% (36.7%; p = 0.03). Median OS was 4.3 years in NET G3, 1.8 years in NEC <55%, and 0.7 years in NEC ≥55% (p <0.0001); it was 2.3 years with NGS wild-type, 0.7 years with ≥1 mutation (p <0.0001), 0.8 years in PD-L1-positive patients, and 1.7 years in PD-L1-negative subjects (p = 0.0004). In multivariate analysis, only the proposed subclassification approach yielded statistically significant differences between groups (NEC <55% vs. NET G3, HR 14.1, 95% CI 2.2-89.8, p = 0.005; NEC ≥55% vs. NET G3, HR 25.8, 95% CI 3.9-169, p = 0.0007). Conclusions: These findings identify NEC ≥55% as a biologically and prognostically distinct subtype and pave the way for more personalized treatment
Evidence of Resistance to Cry34/35Ab1 Corn by Western Corn Rootworm (Coleoptera: Chrysomelidae): Root Injury in the Field and Larval Survival in Plant-Based Bioassays
Western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is a serious pest of corn in the United States, and recent management of western corn rootworm has included planting of Bt corn. Beginning in 2009, western corn rootworm populations with resistance to Cry3Bb1 corn and mCry3A corn were found in Iowa and elsewhere. To date, western corn rootworm populations have remained susceptible to corn producing Bt toxin Cry34/35Ab1. In this study, we used single-plant bioassays to test field populations of western corn rootworm for resistance to Cry34/35Ab1 corn, Cry3Bb1 corn, and mCry3A corn. Bioassays included nine rootworm populations collected from fields where severe injury to Bt corn had been observed and six control populations that had never been exposed to Bt corn. We found incomplete resistance to Cry34/35Ab1 corn among field populations collected from fields where severe injury to corn producing Cry34/35Ab1, either singly or as a pyramid, had been observed. Additionally, resistance to Cry3Bb1 corn and mCry3A corn was found among the majority of populations tested. These first cases of resistance to Cry34/35Ab1 corn, and the presence of resistance to multiple Bt toxins by western corn rootworm, highlight the potential vulnerability of Bt corn to the evolution of resistance by western corn rootworm. The use of more diversified management practices, in addition to insect resistance management, likely will be essential to sustain the viability of Bt corn for management of western corn rootworm
Microenvironment and tumor inflammatory features improve prognostic prediction in gastro-entero-pancreatic neuroendocrine neoplasms
Microenvironment-related immune and inflammatory markers, when combined with established Ki-67 and morphology parameters, can improve prognostic prediction in gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs). Therefore, we evaluated the prognostic value of microenvironment and tumor inflammatory features (MoTIFs) in GEP-NENs. For this purpose, formalin-fixed paraffin-embedded tissue sections from 350 patients were profiled by immunohistochemistry for immune, inflammatory, angiogenesis, proliferation, NEN-, and fibroblast-related markers. A total of 314 patients were used to generate overall survival (OS) and disease-free survival (DFS) MoTIFs prognostic indices (PIs). PIs and additional variables were assessed using Cox models to generate nomograms for predicting 5-year OS and DFS. A total of 36 patients were used for external validation of PIs and nomograms' prognostic segregations. From our analysis, G1/G2 versus G3 GEP-NENs showed phenotypic divergence with immune-inflammatory markers. HLA, CD3, CD8, and PD-1/PD-L1 IHC expression separated G3 into two sub-categories with high versus low adaptive immunity-related features. MoTIFs PI for OS based on COX-2Tumor(T) > 4, PD-1Stromal(S) > 0, CD8S < 1, and HLA-IS < 1 was associated with worst survival (hazard ratio [HR] 2.50; 95% confidence interval [CI], 2.12–2.96; p < 0.0001). MoTIFs PI for DFS was based on COX-2T > 4, PD-1S > 4, HLA-IS < 1, HLA-IT < 2, HLA-DRS < 6 (HR 1.77; 95% CI, 1.58–1.99; p < 0.0001). Two nomograms were developed including morphology (HR 4.83; 95% CI, 2.30–10.15; p < 0.001) and Ki-67 (HR 11.32; 95% CI, 5.28–24.24; p < 0.001) for OS, and morphology (PI = 0: HR 10.23; 95% CI, 5.67–18.47; PI = 5: HR 2.87; 95% CI, 1.21–6.81; p < 0.001) and MoTIFs PI for DFS in well-differentiated GEP-NENs (HR 6.21; 95% CI, 2.52–13.31; p < 0.001). We conclude that G1/G2 to G3 transition is associated with immune-inflammatory profile changes; in fact, MoTIFs combined with morphology and Ki-67 improve 5-year DFS prediction in GEP-NENs. The immune context of a subset of G3 poorly differentiated tumors is consistent with activation of adaptive immunity, suggesting a potential for responsiveness to immunotherapy targeting immune checkpoints
(188)Re radiopharmaceuticals for radiosynovectomy: evaluation and comparison of tin colloid, hydroxyapatite and tin-ferric hydroxide macroaggregates
BACKGROUND: Radiosynovectomy is a therapy used to relieve pain and inflammation from rheumatoid arthritis and related diseases. In this study three (188)Re particulate compounds were characterized according to their physico-chemical properties and their biological behavior in rabbits. The results were compared in order to establish which was the radiopharmaceutical that better fits the requirements of this kind of radiotherapy. METHODS: Three radiopharmaceutical formulations, tin colloid, hydroxyapatite particles (HA) and ferric hydroxide macroaggregates coated with tin colloid (FHMA), were physically characterized (number, volume and surface of the particles). For this purpose laser diffraction methodology was used. To evaluate cavity leakage of activity the following studies in New Zealand rabbits were performed: scintigraphic images for 48 hr after intraarticular injection of each radiopharmaceutical, biodistribution at 48 hr and urine samples collection during the first 24 hr post-radiopharmaceutical administration. RESULTS: Labeling procedures for (188)Re-HA and (188)Re-Sn-FHMA were labour intensive while (188)Re-Sn was easily prepared. Furthermore, (188)Re-Sn colloid offered the greatest surface area in the 2–10 microm range and was obtained with a radiochemical purity over 95%, while percentage of bound activity for (188)Re-HA and (188)Re-Sn-FHMA were 55% and 92% respectively. Stability was verified for the three radiopharmaceuticals for 24 hr. Scintigraphic studies and biodistribution in rabbits after intraarticular administration of the radiopharmaceuticals showed relevant activity only in the knee, this being over 90% of the residual activity in the whole body at 48 hr in every case. Renal elimination of (188)Re-Sn colloid and (188)Re-Sn-FHMA was detected by activity measurements in urine samples, during the first 12 hr post-radiopharmaceutical injection. The percentage of activity retained in the knee was 69.1% for (188)Re-Sn colloid, 55.1% for (188)Re-Sn-FHMA and 33.6% for (188)Re-HA. CONCLUSION: The (188)Re-Sn colloid was easy to prepare, minimum facilities were required, was stable for 24 hr and showed minimal leakage from the joint after intraarticular injection into the rabbit's knee. Furthermore, (188)Re-Sn colloid has greater retention in the knee when it is compared with the other radiopharmaceuticals, so it could provide the best therapeutic effect/absorbed dose ratio for the patient
Analysis of predictive factors influencing dupilumab continuation rate in adult patients with atopic dermatitis. results from an italian multicenter study
Objectives: The purpose of this study was to analyze the drug survival rate of dupilumab up to 2 years in a large real-world cohort of adult patients affected by moderate/severe atopic dermatitis (AD), and to investigate the clinical, demographic and predictive factors influencing the patients’ treatment persistence. Material and methods: This study included adult patients affected by moderate-to-severe AD treated with dupilumab for at least 16 weeks who visited 7 dermatologic outpatient clinics in Lazio, Italy, from January 2019 until August 2021. Results: A total of 659 adult patients (345 male [52.3%], mean age: 42.8 years) with an average treatment duration of 23.3 months were enrolled in the study. Overall, 88.6% and 76.1% of patients were still on treatment after 12 and 24 months, respectively. The drug survival rate for discontinuation due to AEs and dupilumab ineffectiveness was 95.0% at 12 months and 90.0% at 24 months. The main reasons for drug discontinuation included inefficacy (29.6%), failed compliance (17.4%), persistent efficacy (20.4%) and adverse events (7.8%). Adult AD onset (≥18 years) and EASI score severity measured at the last follow-up visit were the only factors significantly associated with lower drug survival. Conclusion: This study revealed an increased cumulative probability of dupilumab survival at 2 years, reflected by a sustained effectiveness and a favorable safety profile of the drug
A Monte Carlo simulation study comparing linear regression, beta regression, variable-dispersion beta regression and fractional logit regression at recovering average difference measures in a two sample design
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Mouse genomic screen reveals novel host regulator of metastasis
Tumor cells have to overcome challenges in the host tissue microenvironment to metastasize successfully to distant organs. In a recent Nature study, a genome-wide functional screen demonstrated that deficiency of the sphingosine-1-phoshate (S1P) transporter gene Spns2 in endothelium increased immune-mediated cell killing by T cells and natural killer (NK) cells, thereby suppressing metastatic colonization
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