The dependence of the performance of OC1C10‐PPV:PCBM (poly(2‐methoxy‐5‐(3′,7′‐dimethyloctyloxy)‐p‐phenylene vinylene):methanofullerene 6,6‐phenyl C61‐butyric acid methyl ester)‐based bulk ...heterojunction solar cells on their composition has been investigated. With regard to charge transport, we demonstrate that the electron mobility gradually increases on increasing the PCBM weight ratio, up to 80 wt.‐%, and subsequently saturates to its bulk value. Surprisingly, the hole mobility in the PPV phase shows an identical behavior and saturates beyond 67 wt.‐% PCBM, a value which is more than two orders of magnitude higher than that of the pure polymer. The experimental electron and hole mobilities were used to study the photocurrent generation of OC1C10‐PPV:PCBM bulk‐heterojunction (BHJ) solar cells. From numerical calculations, it is shown that for PCBM concentrations exceeding 80 wt.‐% reduced light absorption is responsible for the loss of device performance. From 80 to 67 wt.‐%, the decrease in power conversion efficiency is mainly due to a decreased separation efficiency of bound electron–hole (e–h) pairs. Below 67 wt.‐%, the performance loss is governed by a combination of a reduced generation rate of e–h pairs and a strong decrease in hole transport.
The performance of polymer–fullerene bulk‐heterojunction solar cells has been investigated as a function of fullerene content. Electron and hole mobilities were measured separately in the blend (see Figure). The maximum power conversion efficiency is achieved at a high fullerene fraction, where light harvesting is less effective, which is explained using numerical simulations including the measured electron and hole mobilities.
Pleural and pericardial involvements are well recognized in eosinophilic granulomatosis with polyangiitis (EGPA) but considered rare manifestations of the other forms of antineutrophil cytoplasmic ...autoantibody (ANCA)-associated vasculitis (AAV).
What are the frequency and clinical characteristics of pleuritis and pericarditis in AAV?
and Methods: Using an institutional database of 1,830 patients with AAV, we analyzed clinical notes and diagnosis codes for key words related to pleuritis and pericarditis. Chart review to confirm these findings was performed.
Eighty-eight of 1,058 patients (8.3%) with granulomatosis with polyangiitis (GPA), 27 of 267 (10.1%) with microscopic polyangiitis (MPA), and 35 of 201 (17.4%) with EGPA had a manifestation of pleuritis and/or pericarditis attributable to vasculitis. There was a higher frequency of pericarditis in EGPA compared with that in the other AAVs (P < .01). There was no difference in the frequency of pleuritis in GPA, MPA, or EGPA. In the 156 patients with AAV with pleuritis and/or pericarditis, this was a presenting feature in 127 (81.4%). Overall, it was a presenting feature in 6.9% of all patients with AAV, including 6.5% with GPA, 8.6% with MPA, and 15.9% with EGPA.
Pleuritis and pericarditis occur across all the AAVs and, when present, are commonly presenting features of these diseases. Patients with EGPA have a higher proportion of pericardial involvement compared with pleural involvement, whereas this distribution is more equal in patients with GPA and MPA. Pleuritis and pericarditis are underrecognized features of AAV. All forms of AAV should be considered in the differential diagnosis when evaluating a patient with pleuritis or pericarditis.
Enterovirus genome replication occurs at virus-induced structures derived from cellular membranes and lipids. However, the origin of these replication organelles (ROs) remains uncertain. ...Ultrastructural evidence of the membrane donor is lacking, suggesting that the sites of its transition into ROs are rare or fleeting. To overcome this challenge, we combined live-cell imaging and serial block-face scanning electron microscopy of whole cells to capture emerging enterovirus ROs. The first foci of fluorescently labeled viral protein correlated with ROs connected to the endoplasmic reticulum (ER) and preceded the appearance of ROs stemming from the
-Golgi network. Whole-cell data sets further revealed striking contact regions between ROs and lipid droplets that may represent a route for lipid shuttling to facilitate RO proliferation and genome replication. Our data provide direct evidence that enteroviruses use ER and then Golgi membranes to initiate RO formation, demonstrating the remarkable flexibility with which enteroviruses usurp cellular organelles.
Enteroviruses are causative agents of a range of human diseases. The replication of these viruses within cells relies on specialized membranous structures termed replication organelles (ROs) that form during infection but whose origin remains elusive. To capture the emergence of enterovirus ROs, we use correlative light and serial block-face scanning electron microscopy, a powerful method to pinpoint rare events in their whole-cell ultrastructural context. RO biogenesis was found to occur first at ER and then at Golgi membranes. Extensive contacts were found between early ROs and lipid droplets (LDs), which likely serve to provide LD-derived lipids required for replication. Together, these data establish the dual origin of enterovirus ROs and the chronology of their biogenesis at different supporting cellular membranes.
Far from being simple unicellular entities, bacteria have complex social behaviour and organization, living in large populations, and some even as coherent, multicellular entities. The filamentous ...streptomycetes epitomize such multicellularity, growing as a syncytial mycelium with physiologically distinct hyphal compartments separated by infrequent cross-walls. The viability of mutants devoid of cell division, which can be propagated from fragments, suggests the presence of a different form of compartmentalization in the mycelium. Here we show that complex membranes, visualized by cryo-correlative light microscopy and electron tomography, fulfil this role. Membranes form small assemblies between the cell wall and cytoplasmic membrane, or, as evidenced by FRAP experiments, large protein-impermeable cross-membrane structures, which compartmentalize the multinucleoid mycelium. All areas containing cross-membrane structures are nucleoid-restricted zones, suggesting that the membrane assemblies may also act to protect nucleoids from cell-wall restructuring events. Our work reveals a novel mechanism of controlling compartmentalization and development in multicellular bacteria.
Gene expression-based classification systems have identified an aggressive colon cancer subtype with mesenchymal features, possibly reflecting epithelial-to-mesenchymal transition (EMT) of tumor ...cells. However, stromal fibroblasts contribute extensively to the mesenchymal phenotype of aggressive colon tumors, challenging the notion of tumor EMT. To separately study the neoplastic and stromal compartments of colon tumors, we have generated a stroma gene filter (SGF). Comparative analysis of stroma
and stroma
tumors shows that the neoplastic cells in stroma
tumors express specific EMT drivers (ZEB2, TWIST1, TWIST2) and that 98% of differentially expressed genes are strongly correlated with them. Analysis of differential gene expression between mesenchymal and epithelial cancer cell lines revealed that hepatocyte nuclear factor 4α (HNF4α), a transcriptional activator of intestinal (epithelial) differentiation, and its target genes are highly expressed in epithelial cancer cell lines. However, mesenchymal-type cancer cell lines expressed only part of the mesenchymal genes expressed by tumor-derived neoplastic cells, suggesting that external cues were lacking. We found that collagen-I dominates the extracellular matrix in aggressive colon cancer. Mimicking the tumor microenvironment by replacing laminin-rich Matrigel with collagen-I was sufficient to induce tumor-specific mesenchymal gene expression, suppression of HNF4α and its target genes, and collective tumor cell invasion of patient-derived colon tumor organoids. The data connect collagen-rich stroma to mesenchymal gene expression in neoplastic cells and to collective tumor cell invasion. Targeting the tumor-collagen interface may therefore be explored as a novel strategy in the treatment of aggressive colon cancer.
Purpose
To evaluate whether quantitative
18
FFDG-PET/CT assessment, including radiomic analysis of
18
FFDG-positive thyroid nodules, improved the preoperative differentiation of indeterminate ...thyroid nodules of non-Hürthle cell and Hürthle cell cytology.
Methods
Prospectively included patients with a Bethesda III or IV thyroid nodule underwent
18
FFDG-PET/CT imaging. Receiver operating characteristic (ROC) curve analysis was performed for standardised uptake values (SUV) and SUV-ratios, including assessment of SUV cut-offs at which a malignant/borderline neoplasm was reliably ruled out (≥ 95% sensitivity).
18
FFDG-positive scans were included in radiomic analysis. After segmentation at 50% of SUV
peak
, 107 radiomic features were extracted from
18
FFDG-PET and low-dose CT images. Elastic net regression classifiers were trained in a 20-times repeated random split. Dimensionality reduction was incorporated into the splits. Predictive performance of radiomics was presented as mean area under the ROC curve (AUC) across the test sets.
Results
Of 123 included patients, 84 (68%) index nodules were visually
18
FFDG-positive. The malignant/borderline rate was 27% (33/123). SUV-metrices showed AUCs ranging from 0.705 (95% CI, 0.601–0.810) to 0.729 (0.633–0.824), 0.708 (0.580–0.835) to 0.757 (0.650–0.864), and 0.533 (0.320–0.747) to 0.700 (0.502–0.898) in all (
n
= 123), non-Hürthle (
n
= 94), and Hürthle cell (
n
= 29) nodules, respectively. At SUV
max
, SUV
peak
, SUV
max
-ratio, and SUV
peak
-ratio cut-offs of 2.1 g/mL, 1.6 g/mL, 1.2, and 0.9, respectively, sensitivity of
18
FFDG-PET/CT was 95.8% (95% CI, 78.9–99.9%) in non-Hürthle cell nodules. In Hürthle cell nodules, cut-offs of 5.2 g/mL, 4.7 g/mL, 3.4, and 2.8, respectively, resulted in 100% sensitivity (95% CI, 66.4–100%). Radiomic analysis of 84 (68%)
18
FFDG-positive nodules showed a mean test set AUC of 0.445 (95% CI, 0.290–0.600) for the PET model.
Conclusion
Quantitative
18
FFDG-PET/CT assessment ruled out malignancy in indeterminate thyroid nodules. Distinctive, higher SUV cut-offs should be applied in Hürthle cell nodules to optimize rule-out ability. Radiomic analysis did not contribute to the additional differentiation of
18
FFDG-positive nodules.
Trial registration number
This trial is registered with ClinicalTrials.gov: NCT02208544 (5 August 2014),
https://clinicaltrials.gov/ct2/show/NCT02208544
.
Archival formalin-fixed, paraffin-embedded (FFPE) tissue samples with clinical and histological data are a singularly valuable resource for developing new molecular biomarkers. However, transcriptome ...analysis remains challenging with standard mRNA-seq methods as FFPE derived-RNA samples are often highly modified and fragmented. The recently developed 3' mRNA-seq method sequences the 3' region of mRNA using unique molecular identifiers (UMI), thus generating gene expression data with minimal PCR bias. In this study, we evaluated the performance of 3' mRNA-Seq using Lexogen QuantSeq 3' mRNA-Seq Library Prep Kit FWD with UMI, comparing with TruSeq Stranded mRNA-Seq and RNA Exome Capture kit. The fresh-frozen (FF) and FFPE tissues yielded nucleotide sizes range from 13 to > 70% of DV200 values; input amounts ranged from 1 ng to 100 ng for validation. The total mapped reads of QuantSeq 3' mRNA-Seq to the reference genome ranged from 99 to 74% across all samples. After PCR bias correction, 3 to 56% of total sequenced reads were retained. QuantSeq 3' mRNA-Seq data showed highly reproducible data across replicates in Universal Human Reference RNA (UHR, R > 0.94) at input amounts from 1 ng to 100 ng, and FF and FFPE paired samples (R = 0.92) at 10 ng. Severely degraded FFPE RNA with less than or equai to30% of DV200 value showed good concordance (R > 0.87) with 100 ng input. A moderate correlation was observed when directly comparing QuantSeq 3' mRNA-Seq data with TruSeq Stranded mRNA-Seq (R = 0.78) and RNA Exome Capture data (R > 0.67). In this study, QuantSeq 3' mRNA-Seq with PCR bias correction using UMI is shown to be a suitable method for gene quantification in both FF and FFPE RNAs. 3' mRNA-Seq with UMI may be applied to severely degraded RNA from FFPE tissues generating high-quality sequencing data.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Purpose
To assess the impact of an
18
FFDG-PET/CT-driven diagnostic workup to rule out malignancy, avoid futile diagnostic surgeries, and improve patient outcomes in thyroid nodules with ...indeterminate cytology.
Methods
In this double-blinded, randomised controlled multicentre trial, 132 adult euthyroid patients with scheduled diagnostic surgery for a Bethesda III or IV thyroid nodule underwent
18
FFDG-PET/CT and were randomised to an
18
FFDG-PET/CT-driven or diagnostic surgery group. In the
18
FFDG-PET/CT-driven group, management was based on the
18
FFDG-PET/CT result: when the index nodule was visually
18
FFDG-positive, diagnostic surgery was advised; when
18
FFDG-negative, active surveillance was recommended. The nodule was presumed benign when it remained unchanged on ultrasound surveillance. In the diagnostic surgery group, all patients were advised to proceed to the scheduled surgery, according to current guidelines. The primary outcome was the fraction of unbeneficial patient management in one year, i.e., diagnostic surgery for benign nodules and active surveillance for malignant/borderline nodules. Intention-to-treat analysis was performed. Subgroup analyses were performed for non-Hürthle cell and Hürthle cell nodules.
Results
Patient management was unbeneficial in 42% (38/91 95% confidence interval CI, 32–53%) of patients in the
18
FFDG-PET/CT-driven group, as compared to 83% (34/41 95% CI, 68–93%) in the diagnostic surgery group (
p
< 0.001).
18
FFDG-PET/CT-driven management avoided 40% (25/63 95% CI, 28–53%) diagnostic surgeries for benign nodules: 48% (23/48 95% CI, 33–63%) in non-Hürthle cell and 13% (2/15 95% CI, 2–40%) in Hürthle cell nodules (
p
= 0.02). No malignant or borderline tumours were observed in patients under surveillance. Sensitivity, specificity, negative and positive predictive value, and benign call rate (95% CI) of
18
FFDG-PET/CT were 94.1% (80.3–99.3%), 39.8% (30.0–50.2%), 95.1% (83.5–99.4%), 35.2% (25.4–45.9%), and 31.1% (23.3–39.7%), respectively.
Conclusion
An
18
FFDG-PET/CT-driven diagnostic workup of indeterminate thyroid nodules leads to practice changing management, accurately and oncologically safely reducing futile surgeries by 40%. For optimal therapeutic yield, application should be limited to non-Hürthle cell nodules.
Trial registration number
This trial is registered with ClinicalTrials.gov: NCT02208544 (5 August 2014),
https://clinicaltrials.gov/ct2/show/NCT02208544
.
Coronaviruses are enveloped viruses containing the largest reported RNA genomes. As a result of their pleomorphic nature, our structural insight into the coronavirion is still rudimentary, and it is ...based mainly on 2D electron microscopy. Here we report the 3D virion structure of coronaviruses obtained by cryo-electron tomography. Our study focused primarily on the coronavirus prototype murine hepatitis virus (MHV). MHV particles have a distinctly spherical shape and a relatively homogenous size (almost equal to85 nm envelope diameter). The viral envelope exhibits an unusual thickness (7.8 ± 0.7 nm), almost twice that of a typical biological membrane. Focal pairs revealed the existence of an extra internal layer, most likely formed by the C-terminal domains of the major envelope protein M. In the interior of the particles, coiled structures and tubular shapes are observed, consistent with a helical nucleocapsid model. Our reconstructions provide no evidence of a shelled core. Instead, the ribonucleoprotein seems to be extensively folded onto itself, assuming a compact structure that tends to closely follow the envelope at a distance of almost equal to4 nm. Focal contact points and thread-like densities connecting the envelope and the ribonucleoprotein are revealed in the tomograms. Transmissible gastroenteritis coronavirion tomograms confirm all the general features and global architecture observed for MHV. We propose a general model for the structure of the coronavirion in which our own and published observations are combined.
Objective
Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis of medium‐sized visceral vessels. However, cutaneous arteritis (CA) and gastrointestinal (GI) vasculitis are forms of ...single‐organ vasculitis having indistinguishable histopathologic findings from PAN. The aim of this study was to evaluate and compare the clinical characteristics, treatment, and outcomes of patients with systemic PAN, CA, and GI vasculitis.
Methods
Retrospective cohorts were assembled, consisting of patients with PAN, CA, and GI vasculitis between 1980 and 2014. The demographics, clinical characteristics, treatment, and outcomes of patients were ed from medical records.
Results
We included 48 patients with PAN, 41 patients with CA, and 19 patients with GI vasculitis. The disease of 1 patient evolved from CA to systemic PAN during the disease course. At diagnosis, 94% of patients with PAN, 93% of patients with CA, and 67% of patients with GI vasculitis were treated with glucocorticoids. Additional immunosuppressive agents were used in 67% of PAN, 37% of GI vasculitis, and 32% of CA cases. The 5‐year cumulative relapse rate was 45.2% in CA, and only 9.6% in PAN during a followup of approximately 6 years. No deaths were observed in the CA group. The survival rate at 10 years was 66% in the PAN group and 61% in the GI vasculitis group.
Conclusion
Systemic PAN, CA, and GI vasculitis take different clinical courses and therefore may be different diseases, rather than existing on a spectrum of the same disease. Progression of CA to systemic PAN is very rare. Relapse risk is low during followup in PAN. Patients with CA have a higher relapse rate than those with systemic PAN, possibly due to less use of immunosuppressive therapy in CA.
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