To date, the role of NODAL in normal and abnormal L-R asymmetry has been well established. In a recent paper, mutations of this gene have been reported in heterotaxy but also in transposition with D- or L-ventricular loop. The effects of NODAL and other laterality genes can be recognized separately in all three cardiac segments: for topology and septation of the atria, for ventricular looping, and for spiralization and alignment of the great arteries.

Lymphomas are a diverse group of neoplastic disorders arising primarily in lymph nodes. They have been majorly classified into Hodgkin and Non-Hodgkin lymphomas(NHL). NHL can be of B, T and Null cell categories having further subtypes based on their histological characteristics. Lymphomas can be nodal and extra nodal. The head and neck area are the second most common site of extra nodal lymphoma, with tonsils being the most common site of involvement; other sites include the nasopharynx and tongue base. B- Cell type being the most common type. Predominantly occurs in elderly. Presentations depends on the site involved. Various modalities like surgical treatment, chemotherapy (or) radiotherapy is available. Each stage has varied survival rates and prognosis and responses to the treat depending on the patient factors. In this paper,  we report two cases of patients with non-Hodgkin lymphoma of tonsil, where the preoperative clinical diagnosis and radiological diagnosis was inconclusive and final diagnosis was established based on histopathological examination.

Dicer substrate interfering RNAs (DsiRNAs) destroy targeted transcripts using the RNA-Induced Silencing Complex (RISC) through a process called RNA interference (RNAi). This process is ubiquitous among eukaryotes. Here we report the utility of DsiRNA in embryos of the sea urchin Lytechinus variegatus (Lv). Specific knockdowns phenocopy known morpholino and inhibitor knockdowns, and DsiRNA offers a useful alternative to morpholinos. Methods are described for the design of specific DsiRNAs that lead to destruction of targeted mRNA. DsiRNAs directed against pks1, an enzyme necessary for pigment production, show how successful DsiRNA perturbations are monitored by RNA in situ analysis and by qPCR to determine relative destruction of targeted mRNA. DsiRNA-based knockdowns phenocopy morpholino- and drug-based inhibition of nodal and lefty. Other knockdowns demonstrate that the RISC operates early in development as well as on genes that are first transcribed hours after gastrulation is completed. Thus, DsiRNAs effectively mediate destruction of targeted mRNA in the sea urchin embryo. The approach offers significant advantages over other widely used methods in the urchin in terms of cost, and ease of procurement, and offers sizeable experimental advantages in terms of ease of handling, injection, and knockdown validation.

Objective This study aims to investigate breast cancer lymph node involvement in a West Indian population while correlating it with various histological parameters and evaluating the role of the sentinel lymph node biopsy. Method This is a retrospective study where histology reports for all breast cancer-related biopsies from 2018 to 2021, totaling 813 samples, were obtained. Histological parameters from these reports were extracted into a spreadsheet and analyzed using Statistical Product and Service Solutions (SPSS, version 28.0; IBM SPSS Statistics for Windows, Armonk, NY) software for TNM staging and axillary and sentinel lymph node dissections, among other fields found in histology reports. Results In 44.8% of cases, patients present at the T2 stage with associated lymph node spread. Each T stage had more lymph nodes involved than uninvolved for tumors sized T2 and higher. Inversely, for tumors staged under T2, there were generally more uninvolved lymph nodes than involved ones. Larger tumors were found to have advanced N staging, especially in the T3 category, where a significantly higher proportion of cases were found to have N2 and N3 staging compared to the other T stages. This trend is also seen in M staging, where larger tumors metastasize more than smaller tumors (40% for T4a, 0% for T1). Despite significant lymph node involvement being observed, sentinel lymph node biopsies were usually negative. Conclusion More patients in this population present with lymph node involvement than without. Larger breast cancer tumors are associated with greater lymph node involvement, particularly at T2 and higher stages. Sentinel lymph node biopsies can be omitted in smaller breast cancer tumors up to 2 cm in size, and the local recurrence rate is low despite a false-negative rate of around 10% in upfront sentinel lymph node biopsy.

Dicer substrate interfering RNAs (DsiRNAs) destroy targeted transcripts using the RNA-Induced Silencing Complex (RISC) through a process called RNA interference (RNAi). This process is ubiquitous among eukaryotes. Here we report the utility of DsiRNA in embryos of the sea urchin Lytechinus variagatus (Lv). Specific knockdowns phenocopy known morpholino and inhibitor knockdowns, and DsiRNA offers a useful alternative to morpholinos. Methods for designing and obtaining specific DsiRNAs that lead to destruction of targeted mRNA are described. DsiRNAs directed against pks1, an enzyme necessary for pigment production, show how successful DsiRNA perturbations are monitored by RNA in situ analysis and by qPCR to determine relative destruction of targeted mRNA. DsiRNA-based knockdowns phenocopy morpholino- and drug-based inhibition of nodal and lefty. Other knockdowns demonstrate that the RISC operates early in development as well as on genes that are first transcribed hours after gastrulation is completed. Thus, DsiRNAs effectively mediate destruction of targeted mRNA in the sea urchin embryo. The approach offers significant advantages over other widely used methods in the urchin in terms of cost, and ease of procurement, and offers sizeable experimental advantages in terms of ease of handling, injection, and knockdown validation.

BACKGROUND: Vertebrate left-right symmetry breaking is preceded by formation of left-right organizer. In Amphibian, this structure is formed by gastrocoel roof plate, which emerges from superficial suprablastoporal cells. GRP is subdivided into medial area, which generates leftward flow by rotating monocilia and lateral Nodal1 expressing areas, which are involved in sensing of the flow. After successful symmetry breaking, medial cells are incorporated into a deep layer where they contribute to the axial mesoderm, while lateral domains join somitic mesoderm.
RESULTS: Here, we performed detailed analysis of spatial and temporal gene expression of important markers and the corresponding morphology of emerging GRP. Endodermal marker Sox17 and markers of superficial mesoderm display complementary patterns at all studied stages. At early stages, GRP forms Tekt2 positive epithelial domain clearly separated from underlying deep layers, while at later stages, this separation disappears. Marker of early somitic mesoderm MyoD1 was absent in emerging GRP and was induced together with Nodal1 during early neurulation. Decreasing morphological separation is accompanied by lateral to medial covering of GRP by endoderm.
CONCLUSIONS: Our data supports continuous link between superficial mesoderm at the start of gastrulation and mature GRP and suggests late induction of somitic fate in lateral GRP.

Congenital heart disease (CHD) is a type of major defect that occurs during embryonic development. Although significant advances have been made in the treatment of CHD, its etiology and molecular mechanism remain unclear. To identify the critical role of SUMOylation in cardiac development, we generated SENP3 knockout mice and showed that SENP3 knockout mice die on embryonic day 8.5 with an open neural tube and reversed left-right cardiac asymmetry. Moreover, SENP3 knockout promoted apoptosis and senescence of H9C2 cells. Further studies showed that Nodal, a critical gene that forms left-right asymmetry, is regulated by SENP3 and that SENP3 regulates cell apoptosis and senescence in a Nodal-dependent manner. Furthermore, Nodal was hyper-SUMOylated after SENP3 knockout, and SUMOylation of Nodal inhibited its ubiquitination and ubiquitin-proteasome degradation pathway. Nodal overexpression enhanced cell apoptosis and senescence; however, the mutation at the SUMOylation site of Nodal reversed its effect on the apoptosis and senescence of H9C2 cells. More importantly, the SENP3-Nodal axis regulates cell senescence by inducing cell autophagy. These results suggest that the SENP3-Nodal signaling axis regulates cardiac senescence-autophagy homeostasis, which in turn affects cardiac development and results in the occurrence of CHD.

Several differentiation protocols have enabled the generation of intermediate mesoderm (IM)-derived cells from human pluripotent stem cells (hPSC). However, the substantial variability between existing protocols for generating IM cells compromises their efficiency, reproducibility, and overall success, potentially hindering the utility of urogenital system organoids. Here, we examined the role of high levels of Nodal signaling and BMP activity, as well as WNT signaling in the specification of IM cells derived from a UCSD167i-99-1 human induced pluripotent stem cells (hiPSC) line. We demonstrate that precise modulation of WNT and BMP signaling significantly enhances IM differentiation efficiency. Treatment of hPSC with 3 μM CHIR99021 induced TBXT+/MIXL1+ mesoderm progenitor (MP) cells after 48 h of differentiation. Further treatment with a combination of 3 μM CHIR99021 and 4 ng/mL BMP4 resulted in the generation of OSR1+/GATA3+/PAX2+ IM cells within a subsequent 48 h period. Molecular characterization of differentiated cells was confirmed through immunofluorescence staining and RT-qPCR. Hence, this study establishes a consistent and reproducible protocol for differentiating hiPSC into IM cells that faithfully recapitulates the molecular signatures of IM development. This protocol holds promise for improving the success of protocols designed to generate urogenital system organoids in vitro, with potential applications in regenerative medicine, drug discovery, and disease modeling.

Defects of situs are associated with complex sets of congenital heart defects in which the normal concordance of asymmetric thoracic and abdominal organs is disturbed. The cellular and molecular mechanisms underlying the formation of the embryonic left-right axis have been investigated extensively in the past decade. This has led to the identification of mutations in at least 33 different genes in humans with heterotaxy and situs defects. Those mutations affect a broad range of molecular components, from transcription factors, signaling molecules, and chromatin modifiers to ciliary proteins. A substantial overlap of these genes is observed with genes associated with other congenital heart diseases such as tetralogy of Fallot and double-outlet right ventricle, d-transposition of the great arteries, and atrioventricular septal defects. In this chapter, we present the broad genetic heterogeneity of situs defects including recent human genomics efforts.

Ventricular septal defects (VSDs) are recognized as one of the commonest congenital heart diseases (CHD), accounting for up to 40% of all cardiac malformations, and occur as isolated CHDs as well as together with other cardiac and extracardiac congenital malformations in individual patients and families. The genetic etiology of VSD is complex and extraordinarily heterogeneous. Chromosomal abnormalities such as aneuploidy and structural variations as well as rare point mutations in various genes have been reported to be associated with this cardiac defect. This includes both well-defined syndromes with known genetic cause (e.g., DiGeorge syndrome and Holt-Oram syndrome) and so far undefined syndromic forms characterized by unspecific symptoms. Mutations in genes encoding cardiac transcription factors (e.g., NKX2-5 and GATA4) and signaling molecules (e.g., CFC1) have been most frequently found in VSD cases. Moreover, new high-resolution methods such as comparative genomic hybridization enabled the discovery of a high number of different copy number variations, leading to gain or loss of chromosomal regions often containing multiple genes, in patients with VSD. In this chapter, we will describe the broad genetic heterogeneity observed in VSD patients considering recent advances in this field.