clifford B.4.1 , an allele of CG1603 , causes tissue overgrowth in the Drosophila melanogaster eye.

Mutant B.4.1 , generated via EMS mutagenesis in Drosophila melanogaster , was studied by undergraduate students participating in the Fly-CURE. After inducing genetically mosaic tissue in the adult eye, B.4.1 mutant tissue displays a robust increase in cell division and a rough appearance. Complementation mapping and sequence analysis identified a nonsense mutation in the gene CG1603 , which we named clifford ( cliff ) due to observed increases in red-pigmented mutant tissue compared to controls. cliff encodes a zinc finger-containing protein implicated in transcriptional control. RNAi knockdown of cliff similarly results in rough eyes, confirming a role for Cliff in eye development.

Blueprint for Implementing and Improving Eligible Inferior Vena Cava Filter Retrieval Across Institutions.

Introduction: Placement of removable inferior vena cava filters (rIVCFs) has increased, but this has not been accompanied by timely removal, with retrieval rates as low as 8.5% at some institutions. Failure to remove rIVCFs that were not medically necessary resulted in increased complications. This study discussed the development of an inferior vena cava (IVC) filter follow-up protocol. Methods: A method to monitor IVC filter placement and retrieval was developed. A weekly report was generated detailing placement and removal of rIVCFs. A standardized retrieval calculator was utilized to determine efficacy of removal. An IVC filter Retrieval Assessment Form was developed. Managing physicians and patients with medically unnecessary filters were sent letters with a retrieval checklist and order form. If not removed within one year, additional letters were sent. Standardized IVC filter reporting templates were created and utilized after insertion of all filters with retrieval status. Letters eventually were built into the electronic medical record for direct routing. Results: From 2015 to 2020, IVC filters were placed in 719 patients. Of those, 58% were eligible for retrieval. Initial rates of rIVCF removal in eligible patients were as low as 30-33% in 2015. The retrieval rate of eligible filters rose to 44% in September 2018. The rate of retrieval rose to 61% in January 2021. Conclusions: Employing a systemic protocol to aid in follow-up of patients following rIVCF placement may improve rates of retrieval. Regular evaluation and revision of the process demonstrated a significant role in achieving an increase in retrieval rates.

Multicenter Evaluation of Survival and Toxicities of Hepatocellular Carcinoma following Radioembolization: Analysis of the RESiN Registry.

PURPOSE: To determine overall survival (OS), progression-free survival (PFS), and toxicity in patients with hepatocellular carcinoma (HCC) in a multicenter, real-world data registry using transarterial radioembolization (TARE) with resin microspheres. MATERIALS AND METHODS: A total of 448 patients with HCC were treated at 36 centers between 2015 and 2019. Treatment history, baseline laboratory and imaging, and treatment goal were assessed. OS and PFS were stratified using Barcelona Clinic Liver Cancer (BCLC) and Child-Pugh (CP) classifications. Kaplan-Meier analyses compared OS and PFS with 95% confidence intervals. Transplants were tracked. Toxicities were assessed using Common Terminology Criteria for Adverse Events v5. Cox proportional hazard of baseline demographics assessed factors affecting survival. RESULTS: Prior chemoembolization and systemic therapy were used in 107 (26%) and 68 (16%) patients, respectively. Using the BCLC staging system, 66 patients (19%) were BCLC A and 202, 51, and 26 were BCLC B, C, and D, respectively. Median OS for patients with BCLC A disease was not achieved at 30 months. Median OS for patients with BCLC B, C, and D disease were 19.5, 13.6, and 11.5 months, respectively (P = .0006). Median PFS for patients with BCLC A, B, C, and D were 19.8, 10.0, 6.3, and 5.9 months, respectively (P = .003). Twenty patients underwent transplantation, representing 14 of 43 (33%) and 6 of 28 (21%) patients who underwent bridging and downstaging therapy, respectively. Common Grade 3 toxicities were encephalopathy (11/448, 2.5%), hyperbilirubinemia (10/448, 2.2%), and ascites (9/448, 2.0%). Factors predicting longer survival included CP A (χ2 = 4.2, P = .04) and BCLC A (χ2 = 5.2, P = .02). CONCLUSIONS: In a frequently pretreated patient cohort with disease burden in 81% beyond the Milan criteria, TARE with resin microspheres provided OS comparable to other studies in this multicenter registry.

Surgical Size Reduction of Zebrafish for the Study of Embryonic Pattern Scaling.

In the developmental process, embryos exhibit a remarkable ability to match their body pattern to their body size; their body proportion is maintained even in embryos that are larger or smaller, within certain limits. Although this phenomenon of scaling has attracted attention for over a century, understanding the underlying mechanisms has been limited, owing in part to a lack of quantitative description of developmental dynamics in embryos of varied sizes. To overcome this limitation, we developed a new technique to surgically reduce the size of zebrafish embryos, which have great advantages for in vivo live imaging. We demonstrate that after balanced removal of cells and yolk at the blastula stage in separate steps, embryos can quickly recover under the right conditions and develop into smaller but otherwise normal embryos. Since this technique does not require special equipment, it is easily adaptable, and can be used to study a wide range of scaling problems, including robustness of morphogen mediated patterning.

Size-reduced embryos reveal a gradient scaling-based mechanism for zebrafish somite formation.

Little is known about how the sizes of animal tissues are controlled. A prominent example is somite size, which varies widely both within an individual and across species. Despite intense study of the segmentation clock governing the timing of somite generation, how it relates to somite size is poorly understood. Here, we examine somite scaling and find that somite size at specification scales with the length of the presomitic mesoderm (PSM) despite considerable variation in PSM length across developmental stages and in surgically size-reduced embryos. Measurement of clock period, axis elongation speed and clock gene expression patterns demonstrate that existing models fail to explain scaling. We posit a 'clock and scaled gradient' model, in which somite boundaries are set by a dynamically scaling signaling gradient across the PSM. Our model not only explains existing data, but also makes a unique prediction that we confirm experimentally - the formation of periodic 'echoes' in somite size following perturbation of the size of one somite. Our findings demonstrate that gradient scaling plays a central role in both progression and size control of somitogenesis.

Single-cell mapping of gene expression landscapes and lineage in the zebrafish embryo.

High-throughput mapping of cellular differentiation hierarchies from single-cell data promises to empower systematic interrogations of vertebrate development and disease. Here we applied single-cell RNA sequencing to >92,000 cells from zebrafish embryos during the first day of development. Using a graph-based approach, we mapped a cell-state landscape that describes axis patterning, germ layer formation, and organogenesis. We tested how clonally related cells traverse this landscape by developing a transposon-based barcoding approach (TracerSeq) for reconstructing single-cell lineage histories. Clonally related cells were often restricted by the state landscape, including a case in which two independent lineages converge on similar fates. Cell fates remained restricted to this landscape in embryos lacking the chordin gene. We provide web-based resources for further analysis of the single-cell data.

Observing the cell in its native state: Imaging subcellular dynamics in multicellular organisms.

True physiological imaging of subcellular dynamics requires studying cells within their parent organisms, where all the environmental cues that drive gene expression, and hence the phenotypes that we actually observe, are present. A complete understanding also requires volumetric imaging of the cell and its surroundings at high spatiotemporal resolution, without inducing undue stress on either. We combined lattice light-sheet microscopy with adaptive optics to achieve, across large multicellular volumes, noninvasive aberration-free imaging of subcellular processes, including endocytosis, organelle remodeling during mitosis, and the migration of axons, immune cells, and metastatic cancer cells in vivo. The technology reveals the phenotypic diversity within cells across different organisms and developmental stages and may offer insights into how cells harness their intrinsic variability to adapt to different physiological environments.