Ahamed Bilal
Ocimum species known for its traditional value,which is used as culinary herb and assigned as medicine and spice plant. We used molecular techniques to assess the genetic variability and relatedness of 20 accessions of three germplasm of Ocimum spp. (Ocimum gratissimum, Ocimum sanctum and Ocimum basilicum) collected from different places. DNA was isolated by fixing a sample in alcohol without using liquid nitrogen. Molecular markers were used to assess genetic diversity in basil (Ocimum L. spp., Lamiaceae). Varieties were analyzed through RAPD markers with five Inter-simple sequence repeats (ISSR) primers to determine the extent of molecular characterization. PCR amplification of these regions using a single primer yields multiple amplification products that can be used as a dominant multi locus marker system for the study of genetic variation in various organisms. and the result showed various gene expression with the ISSR primer than RAPD markers and we found a maximum number of unique alleles were observed in O. basillicum with ISSR primer (1, 5, 8, 9, 11, 12, 13, 14) which mentioned on primer synthesized table. Among the 15 ISSR primers tested, we have got bands in the size range of 300 bp to 850 bp. Our observations suggested that morphological variability and ISSR analysis could help in identifying genetic variations among different varieties of basil, help in plant improvement and develop a well-organized way to conserve the genetic wealth of basil varieties. DNA based markers like ISSR are more useful than the traditional morphological and biochemical markers. Genetic relationships were examined among thirty germplasm accessions belonging to five Ocimum species using RAPD and ISSR markers.
Izidor Kern, Tanja Cufer, Mitja Rot, Katja Mohorcic, Igor Pozek, John F Palma, Sidney A Scudder, Partha M Das and Aleksander Sadikov
DOI: 10.37421/jmbd.2020.11.425
Serial monitoring of circulating tumor DNA may predict resistance to first-line epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors before CT-confirmed progression. Our objective was to evaluate dynamic changes in plasma EGFR-activating mutations as an early predictor of disease progression before clinical or radiological evidence. For this observational study, 35 patients with advanced, EGFR-positive, nonsquamous, non-small cell lung cancer were enrolled. All patients were initiating or receiving EGFR tyrosine kinase inhibitors and had received at least one follow-up CT scan. Peripheral blood samples were collected at each clinical visit, and CT scans were scheduled every 8 to 16 weeks after tyrosine kinase inhibitor initiation and upon clinical/symptom progression. Of the 35 patients, 16 experienced reappearance of EGFRactivating mutations and disease progression. Of these, 12 patients experienced reappearance of EGFR-activating mutations before CT-confirmed progression, 3 had CT-confirmed progression one visit (8 weeks) before detectable EGFR-activating mutations, and 1 had EGFR-activating mutations reappear concurrently with CT-confirmed progression. EGFR-activating mutations reappeared at a mean of 10 weeks (median, 16 weeks) before routinely scheduled CT-confirmed progression. Using study-specific definitions, we observed 5 false positives and no false negatives. This study demonstrates that dynamic changes in circulating tumor DNA can predict resistance to EGFR-TKIs before CT-confirmed progression. Further prospective trials of this promising approach with potential benefits to patient care should be considered.
