2 research outputs found
Cytomorphology of Castleman’s Disease of Parotid Gland: Pitfalls and Diagnostic Dilemma in a Young Adult
Fine needle aspiration cytology (FNAC) is an easy, effective diagnostic tool that makes it the procedure of choice for all accessible
swellings in the body. Castleman’s disease (CD) may present as unicentric or multicentric swelling hence is subjected to FNAC
very frequently. CD mainly presents mediastinal nodes, nonetheless when present in salivary glands such as parotid, it is often
diagnosed clinically as a salivary gland tumor. However, due to lack of adequate literature on its cytological features and nonspecific radiological findings, the condition is often misdiagnosed. There are few case series on cytological features of CD and even
fewer cases of CD in the parotid gland. Histopathology serves as the gold standard of diagnosis for CD. In superficial locations,
these swellings are easily subjected to direct fine needle aspiration cytology (FNAC). Radiologically guided FNA can be performed
for deeper locations. Hence, the authors present a case of 19 year old male patient, who presented with a small superficial,
preauricular swelling for FNAC. The initial FNAC yielded no conclusive opinion. however a repeat FNAC and histopathological
examination led to the final diagnosis. This case report aims to highlight the cytomorphological and histopathological features of
CD in the Parotid gland and various difficulties encountered in making the final diagnosi
Targeting the aryl hydrocarbon receptor nuclear translocator complex with DMOG and Stemregenin 1 improves primitive hematopoietic stem cell expansion
Culture conditions used for the expansion of hematopoietic stem and progenitor cells (HSCs and HPCs, collectively HSPCs) should ideally favor the self renewal of long-term HSCs. At 20% O2, the synthesis of HIF-1α is balanced by its hydroxylation and proteasomal degradation. This favors HSPC differentiation, but can be prevented by culturing CD34+ cord blood cells in the presence of dimethyloxaloylglycine (DMOG). This differentiation may also be reduced by culturing the cells in the presence of Stemregenin 1, an antagonist of the aryl hydrocarbon receptor (AhR). The objective of this study was to investigate how hypoxia, DMOG and Stemregenin 1 might affect the expansion of HSPCs with the aim of identifying optimal conditions for expansion in culture. It was found that DMOG decreased proliferation but was effective in preserving the number of cells in the primitive hematopoietic sub-populations in vitro. The effect of DMOG was similar to hypoxia, although differences were observed with regard to the side population and CD34+ sub-populations. Stemregenin 1 on the other hand increased the size of the primitive as well as the other HSC sub-populations. The use of Stemregenin 1 with DMOG increased the proportion of primitive HSCs to 3.54% compared to 2.61% for Stemregenin 1 alone. In vivo engraftment studies confirmed these findings and showed that fewer cells (3710) are required for long-term engraftment when HSCs are grown in Stemregenin 1 together with hypoxia than in Stemregenin 1 under conditions of normoxia (13430)