Cell cycle and DNA content of mitotic cells in brain ganglia of drosophila larvae

The programmes of replication of hetero- and euchromatin regions, mitotic cell cycle and the DNA content in metaphases in brain ganglia from late third instar larvae of Drosophila melanogaster (wild type and a tumour bearing mutant, 1(2)gl, strain) and of Drosophila nasuta were examined by autoradiography of [3H]thymidine labelled (continuous or pulse) cells and by cytophotometry, respectively. Brain ganglia labelled continuously with [3H]thymidine for 24 h in vitro showed a significantly high proportion of cells with incorporation of radioactivity restricted to heterochromatin only. Pulse labelling of brain ganglia from larvae of Drosophila melanogaster and Drosophila nasuta followed by chase for different time intervals showed that (i) the frequency of labelled metaphases was more than 50% within 15 to 30 min of chase and remained higher than 50% in nearly all the chase samples till 24 h, (ii) euchromatin labelled metaphases appeared with a low frequency within 1 to 4 h chase period but the heterochromatin labelled metaphases continued to be more common in the later chase samples also, (iii) single chromatid labelled second cycle metaphases were seen within 1 to 4 h after the pulse, but their frequency did not increase in the later samples. Cytophotometry of feulgen-DNA and Hoechst 33258 stained metaphases in late third instar larval brain ganglia revealed a greater variation in the DNA content of individual metaphases, although the means were close to the expected 4 C content. It appears that in relation to the known asymmetric cell divisions of neuroblast and other neural cells, the mitotically active cells in brain ganglia comprise a heterogenous population with widely varying lengths of the different phases of cell cycle; some of them may not cycle regularly and may possibly have a discontinuous S-phase

Association of Antibody-Drug Conjugate (ADC) Target Expression and Interstitial Lung Disease (ILD) in Non-Small-Cell Lung Cancer (NSCLC): Association or Causation or Neither?

Non-small-cell lung cancer (NSCLC) remains a leading cause of cancer-related mortality worldwide, despite advances in immune checkpoint inhibitors and targeted therapies. Antibody-drug conjugates (ADCs) represent a promising therapeutic approach by delivering cytotoxic agents specifically to cancer cells, potentially reducing harm to healthy tissues. This study aims to explore the effectiveness and challenges associated with ADCs in NSCLC, with a focus on drug-induced interstitial lung disease (D-ILD). A comprehensive literature review was conducted across MEDLINE (Ovid), Embase (Elsevier), CENTRAL (Cochrane Library), and other sources up to March 2023, to identify ADCs used in NSCLC treatment and their associated risk of D-ILD. The incidence of ILD was analyzed from clinical trial data, while ADC target expression was examined through RNA and protein levels in normal and tumor lung tissues. Our findings highlight the therapeutic potential of ADCs in NSCLC, as evidenced by significant clinical outcomes. However, the occurrence of D-ILD presents a notable challenge, as its incidence was not directly correlated with the expression levels of the target antigens. This suggests that D-ILD may result from factors beyond antigen expression, including the cytotoxic payload and linker characteristics of ADCs. ADCs offer a promising avenue for NSCLC treatment. Nonetheless, the risk of D-ILD necessitates a balanced approach in ADC development, focusing on optimizing linker and payload properties to mitigate this adverse effect. Further research is essential to better understand and manage D-ILD, ensuring the safe and effective use of ADCs in clinical practice

Evaluation of Programmed Death Ligand 1 Expression in Cytology To Determine Eligibility for Immune Checkpoint Inhibitor Therapy in Patients With Head and Neck Squamous Cell Carcinoma

Background: Immune checkpoint inhibitors targeting the programmed cell death protein 1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway have recently emerged as a frontline treatment for head and neck squamous cell carcinoma (HNSCC). The evaluation of PD-L1 expression by immunohistochemistry in histologic samples is used to determine the eligibility of patients with HNSCC for immunotherapy. Patients with newly diagnosed HNSCC are frequently diagnosed by fine-needle aspiration (FNA) of lymph nodes with metastatic disease. However, the evaluation of PD-L1 expression with the proposed combined positive score (CPS) has not been well established in cytology specimens. Methods: This study retrospectively identified 21 HNSCC patients with a known PD-L1 status from histologic specimens and matched FNA specimens with tumor cells on cell blocks (CBs). The CB sections were stained with a PD-L1 antibody (22C3 clone). All cases were scored with CPS and the tumor proportion score (TPS). Results: The data showed substantial concordance between cytologic and histologic specimens for CPS (agreement, 76.2%; κ = 0.607) and TPS (agreement, 76.2%; κ = 0.607). With histology used as a reference standard, the positive predictive value was 100% for both CPS and TPS, whereas the negative predictive value was 57.1% for CPS assessments and 50% for TPS assessments. Conclusions: PD-L1 expression in HNSCC cytology samples has high concordance with paired histologic samples. PD-L1 CPS evaluation is feasible in HNSCC cytology CBs and can act as a surrogate for determining eligibility for immunotherapy in cases in which a histologic specimen is not readily available

The Second DISPLACE Challenge : DIarization of SPeaker and LAnguage in Conversational Environments

The DIarization of SPeaker and LAnguage in Conversational Environments (DISPLACE) 2024 challenge is the second in the series of DISPLACE challenges, which involves tasks of speaker diarization (SD) and language diarization (LD) on a challenging multilingual conversational speech dataset. In the DISPLACE 2024 challenge, we also introduced the task of automatic speech recognition (ASR) on this dataset. The dataset containing 158 hours of speech, consisting of both supervised and unsupervised mono-channel far-field recordings, was released for LD and SD tracks. Further, 12 hours of close-field mono-channel recordings were provided for the ASR track conducted on 5 Indian languages. The details of the dataset, baseline systems and the leader board results are highlighted in this paper. We have also compared our baseline models and the team's performances on evaluation data of DISPLACE-2023 to emphasize the advancements made in this second version of the challenge.Comment: 5 pages, 3 figures, Interspeech 202

Rapid Detection of Mutations in CSF-cfTNA With the Genexus Integrated Sequencer

PURPOSE: Genomic alterations are fundamental for molecular-guided therapy in patients with breast and lung cancer. However, the turn-around time of standard next-generation sequencing assays is a limiting factor in the timely delivery of genomic information for clinical decision-making. METHODS: In this study, we evaluated genomic alterations in 54 cerebrospinal fluid samples from 33 patients with metastatic lung cancer and metastatic breast cancer to the brain using the Oncomine Precision Assay on the Genexus sequencer. There were nine patients with samples collected at multiple time points. RESULTS: Cell-free total nucleic acids (cfTNA) were extracted from CSF (0.1-11.2 ng/μl). Median base coverage was 31,963× with cfDNA input ranging from 2 to 20 ng. Mutations were detected in 30/54 CSF samples. Nineteen (19/24) samples with no mutations detected had suboptimal DNA input (\u3c 20 ng). The EGFR exon-19 deletion and PIK3CA mutations were detected in two patients with increasing mutant allele fraction over time, highlighting the potential of CSF-cfTNA analysis for monitoring patients. Moreover, the EGFR T790M mutation was detected in one patient with prior EGFR inhibitor treatment. Additionally, ESR1 D538G and ESR1::CCDC170 alterations, associated with endocrine therapy resistance, were detected in 2 mBC patients. The average TAT from cfTNA-to-results was \u3c 24 h. CONCLUSION: In summary, our results indicate that CSF-cfTNA analysis with the Genexus-OPA can provide clinically relevant information in patients with brain metastases with short TAT

A Widespread Distribution of Genomic CeMyoD Binding Sites Revealed and Cross Validated by ChIP-Chip and ChIP-Seq Techniques

Identifying transcription factor binding sites genome-wide using chromatin immunoprecipitation (ChIP)-based technology is becoming an increasingly important tool in addressing developmental questions. However, technical problems associated with factor abundance and suitable ChIP reagents are common obstacles to these studies in many biological systems. We have used two completely different, widely applicable methods to determine by ChIP the genome-wide binding sites of the master myogenic regulatory transcription factor HLH-1 (CeMyoD) in C. elegans embryos. The two approaches, ChIP-seq and ChIP-chip, yield strongly overlapping results revealing that HLH-1 preferentially binds to promoter regions of genes enriched for E-box sequences (CANNTG), known binding sites for this well-studied class of transcription factors. HLH-1 binding sites were enriched upstream of genes known to be expressed in muscle, consistent with its role as a direct transcriptional regulator. HLH-1 binding was also detected at numerous sites unassociated with muscle gene expression, as has been previously described for its mouse homolog MyoD. These binding sites may reflect several additional functions for HLH-1, including its interactions with one or more co-factors to activate (or repress) gene expression or a role in chromatin organization distinct from direct transcriptional regulation of target genes. Our results also provide a comparison of ChIP methodologies that can overcome limitations commonly encountered in these types of studies while highlighting the complications of assigning in vivo functions to identified target sites

The HLH-6 Transcription Factor Regulates C. elegans Pharyngeal Gland Development and Function

The Caenorhabditis elegans pharynx (or foregut) functions as a pump that draws in food (bacteria) from the environment. While the “organ identity factor” PHA-4 is critical for formation of the C. elegans pharynx as a whole, little is known about the specification of distinct cell types within the pharynx. Here, we use a combination of bioinformatics, molecular biology, and genetics to identify a helix-loop-helix transcription factor (HLH-6) as a critical regulator of pharyngeal gland development. HLH-6 is required for expression of a number of gland-specific genes, acting through a discrete cis-regulatory element named PGM1 (Pharyngeal Gland Motif 1). hlh-6 mutants exhibit a frequent loss of a subset of glands, while the remaining glands have impaired activity, indicating a role for hlh-6 in both gland development and function. Interestingly, hlh-6 mutants are also feeding defective, ascribing a biological function for the glands. Pharyngeal pumping in hlh-6 mutants is normal, but hlh-6 mutants lack expression of a class of mucin-related proteins that are normally secreted by pharyngeal glands and line the pharyngeal cuticle. An interesting possibility is that one function of pharyngeal glands is to secrete a pharyngeal lining that ensures efficient transport of food along the pharyngeal lumen