Variation in heat shock protein 40 kDa relates to divergence in thermotolerance among cryptic rotifer species.

Genetic divergence and the frequency of hybridization are central for defining species delimitations, especially among cryptic species where morphological differences are merely absent. Rotifers are known for their high cryptic diversity and therefore are ideal model organisms to investigate such patterns. Here, we used the recently resolved Brachionus calyciflorus species complex to investigate whether previously observed between species differences in thermotolerance and gene expression are also reflected in their genomic footprint. We identified a Heat Shock Protein gene (HSP 40 kDa) which exhibits cross species pronounced sequence variation. This gene exhibits species-specific fixed sites, alleles, and sites putatively under positive selection. These sites are located in protein binding regions involved in chaperoning and may therefore reflect adaptive diversification. By comparing three genetic markers (ITS, COI, HSP 40 kDa), we revealed hybridization events between the cryptic species. The low frequency of introgressive haplotypes/alleles suggest a tight, but not fully impermeable boundary between the cryptic species.

[Evaluation of 99mTc(V)-DMSA imaging in patients with pharyngolaryngeal carcinoma].

OBJECTIVE: To evaluate the value of tumor-seeking agent 99mTc(V)-DMSA in patients with pharyngolaryngeal carcinoma and its biodistribution in human being. METHOD: Planar and SPECT scintigraphy with 99mTc(V)-DMSA were performed in 12 patients with histologically confirmed pharyngolaryngeal carcinoma. The dynamic distribution in patients was also analyzed. RESULT: 9 cases (11 lesions) showed increased uptake by planar imaging and 11 cases (19 lesions) were clearly demonstrated by SPECT images. Furthermore, distant metastatic lesions were showed in 5 patients. Biodistribution in patients showed the accumulation of 99mTc(V)-DMSA in kidney was significantly greater than other organs. CONCLUSION: These results could suggested the clinical utility of 99mTc(V)-DMSA, specially with SPECT, for detecting primary pharyngolaryngealcarcinoma and their metastatic lesions (both local and distant). 99mTc(V)-DMSA Tumor-seeking agent Pharyngolaryngeal carcinoma.