4 research outputs found

    Tumor bed brachytherapy for locally advanced laryngeal cancer: a feasibility assessment of combination with ferromagnetic hyperthermia

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    Purpose. To assess the feasibility of adding hyperthermia to an original method of organ-preserving brachytherapy treatment for locally advanced head and neck tumors. Methods and materials. The method involves organ-preserving tumor resection and adjunctive high-dose-rate (HDR) brachytherapy delivered via afterloading catheters. These catheters are embedded in a polymeric implant prepared intraoperatively to fill the resection cavity, allowing precise computer planning of dose distribution in the surrounding at-risk tumor bed tissue. Theoretical and experimental analyzes address the feasibility of heating the tumor bed implant by coupling energy from a 100 kHz magnetic field applied externally into ferromagnetic particles, which are uniformly distributed within the implant. The goal is to combine adjuvant hyperthermia (40 °C–45 °C) to at-risk tissue within 5 mm of the resection cavity for thermal enhancement of radiation and chemotherapy response. Results. A five-year relapse free survival rate of 95.8% was obtained for a select group of 48 male patients with T3N0M0 larynx tumors, when combining organ-preserving surgery with HDR brachytherapy from a tumor bed implant. Anticipating the need for additional treatment in patients with more advanced disease, a theoretical analysis demonstrates the ability to heat at-risk tissue up to 10 mm from the surface of an implant filled with magnetically coupled ferromagnetic balls. Using a laboratory induction heating system, it takes just over 2 min to increase the target tissue temperature by 10 °C using a 19% volume fraction of ferromagnetic spheres in a 2 cm diameter silicone implant. Conclusion. The promising clinical results of a 48 patient pilot study demonstrate the feasibility of a new organ sparing treatment for laryngeal cancer. Anticipating the need for additional therapy, theoretical estimations of potential implant heating are confirmed with laboratory experiments, preparing the way for future implementation of a thermobrachytherapy implant approach for organ-sparing treatment of locally advanced laryngeal cancer

    Evidence of millet and millet agriculture in the Far East Region of Russia derived from archaeobotanical data and radiocarbon dating

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    Agriculture based on broomcorn and foxtail millet has been identified as one of the main drivers of population expansion and/or resource and innovation transfer across Neolithic and Bronze Age Eurasia. However, accurate reconstruction of spatio-temporal patterns of millet spread within and outside China remains a challenging issue. Here we use a representative set of 27 millet-based radiocarbon (14C) dates from southern Primorye to reconstruct when millet cultivation became part of hunter-fisher-gatherer subsistence in this vast southeasternmost region of Russia. The spatio-temporal distribution of the 14C data demonstrates the following picture. After the earliest conventionally accepted (although not directly dated) appearance of millet at the Krounovka-1 site in the Suifen (Razdol'naya) River catchment west of Khanka Lake around 3521–3356 BCE (95.4% probability range of calibrated ages of wood charcoal), millet agriculture is registered at the site Gvozdevo-4 located on the southern coastal plains northeast of the mouth of the Tumen (Tumannaya) River in the first half of the 3rd millennium BCE. Several archaeological sites (Novoselishche-4, Bogolyubovka-1, Rettikhovka Geologicheskaya-1, Risovoe-4) with directly dated millet indicate the spread of millet cultivation across the fertile plains around Khanka Lake during the second half of the 3rd millennium BCE. The dates obtained from the Olga-10 site on the eastern coastal plains along the Sea of Japan suggest that millet contributed to the food economy there from the beginning of the 2nd millennium BCE. The presented dataset shows the presence of millet in the north-eastern part of the study region (i.e. at the Glazovka-gorodishche site) in the second half of the 1st millennium BCE. Our dataset demonstrates that millet has been cultivated in southern Primorye since the Late Neolithic, when small-scale agriculture was introduced by Zaisanovskaya culture groups archaeologically documented in the study region and neighbouring regions of China and North Korea. This indicates that millet was an integral part of the subsistence economy of the local populations throughout the entire period under review

    Cytogenetic Analysis of the Bimodal Karyotype of the Common European Adder, Vipera berus (Viperidae)

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    Vipera berus is the species with the largest range of snakes on Earth and one of the largest among reptiles in general. It is also the only snake species found in the Arctic Circle. Vipera berus is the most involved species of the genus Vipera in the process of interspecific hybridization in nature. The taxonomy of the genus Vipera is based on molecular markers and morphology and requires clarification using SC-karyotyping. This work is a detailed comparative study of the somatic and meiotic karyotypes of V. berus, with special attention to DNA and protein markers associated with synaptonemal complexes. The karyotype of V. berus is a remarkable example of a bimodal karyotype containing both 16 large macrochromosomes and 20 microchromosomes. We traced the stages of the asynchronous assembly of both types of bivalents. The number of crossing-over sites per pachytene nucleus, the localization of the nucleolar organizer, and the unique heterochromatin block on the autosomal bivalent 6—an important marker—were determined. Our results show that the average number of crossing-over sites per pachytene nucleus is 49.5, and the number of MLH1 sites per bivalent 1 reached 11, which is comparable to several species of agamas
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