Conservation of plant biodiversity by biotechnology methods

Several methods of plant preservation are currently used in the Republic of Kazakhstan: 1) field gene banks in natural growing areas and pomological collections; 2) preservation of seeds at +4°С, –18°С, and –196°С; 3) сold storage of in vitro shoots at +4°С and +10 ± 2°С; 4) cryopreservation of plant tissues and organs at –196°C; 5) preservation of plant DNA at –80°C.Ex situ field collections of plants in Kazakhstan are maintained in botanical gardens of the Republic, arboretums, pomological gardens, nurseries, peasant and farm enterprises, and personal plots. The largest collection of fruit and berry plants is located in the Pomological Garden and includes about 4 thousand varieties, more than 40 thousand hybrids and wild forms of various crops.The Republic of Kazakhstan has about 42,000 accessions in the seed collection. The cereal crop collection is mainly concentrated in the Kazakh Research Institute of Agriculture and Plant Growing – 1/3 of the national genetic resources. The main seed collection of vegetable crops and potatoes (14,700 accessions) is held by the Kazakh Research Institute of Potato and Vegetable Growing. Collections are also available at the Institute of Botany and Phytointroduction and in the Institute of Plant Biology and Biotechnology (IPBB), with the storage mode of + 4°C and –18°C. IPBB also uses cryopreservation technology at –196°C for seed storage.The main in vitro collection of Kazakhstan is kept at the IPBB at + 4°С and +10 ± 2°С; it includes more than 140 accessions of various fruit, berry, nut, vegetable, ornamental, and woody crops, grapes, potatoes, etc. A cryogenic collection of seeds, shoot tips, dormant buds, and embryonic axes in liquid nitrogen (–196°C) is found only in IPBB. The collection includes more than 700 accessions

Определение органных доз внутреннего облучения пациентов при радионуклидной терапии 223Ra -дихлоридом

Radionuclide therapy with 223Ra-dichloride is used to treat bone metastases and to improve the quality of life of patients with metastatic castration-resistant prostate cancer. At the present time there is no reliable data on the biodistribution of the 223Ra-dichloride in the patient body. The aim of this study was to assess absorbed, equivalent doses in radiosensitive organs and tissues and effective dose from internal exposure for patients with metastatic castration-resistant prostate cancer treated with 223Ra-dichloride. Internal doses from 223Ra-dichloride were calculated for a chamber model specific for patients with metastatic castration-resistant prostate cancer. This model consists of 8 chambers (blood plasma, two chambers describing bone tissue, small intestine, upper large intestine, lower large intestine, feces and the rest of the body). Time-integrated activities were calculated using the SAAM II v2.3 software. The IDAC-Dose 2.1 software was used to calculate the absorbed doses. The highest absorbed doses in organs and equivalent doses were determined for the bone surface and red bone marrow. The absorbed dose from a-radiation in the bone surface for a set of six therapeutic procedures with 223Ra-dichloride was estimated as 1 Gy; in the red bone marrow — 0.14 Gy. However, the approach used does not specifically consider accumulation of the radiopharmaceutical in metastases, which can lead to a significant overestimation of the absorbed dose in the healthy part of the bone surface and red bone marrow.Для лечения костных метастазов и улучшения качества жизни пациентов с метастатическим кастрационно-резистентным раком предстательной железы применяют радионуклидную терапию с 223Rа-дихлоридом. Однако в настоящий момент отсутствуют достоверные данные по биораспределению 223Ra-дихлорида в организме пациентов. Целью данной работы являлась оценка поглощенных и эквивалентных доз в радиочувствительных органах и тканях от внутреннего облучения для пациентов с метастатическим кастрационно-резистентным раком предстательной железы при терапии 223Ra-дихлоридом. Дозы внутреннего облучения от 223Ra-дихлорида были рассчитаны для камерной модели пациентов с метастатическим кастрационно-резистентным раком предстательной железы. Данная модель состоит из 8 камер (плазма крови, две камеры, описывающие костную ткань, тонкий кишечник, верхний отдел толстого кишечника, нижний отдел толстого кишечника, кал и остальная часть тела). С использованием программного обеспечения SAAM II v2.3. были рассчитаны интегрированные по времени активности. Для расчета поглощенных доз использовали программное обеспечение IDAC-Dose 2.1. Самые высокие поглощенные дозы в органах и эквивалентные дозы определены для поверхности кости и красного костного мозга. Поглощенная доза от а-излучения в поверхности кости за серию из шести терапевтических процедур с введением 22^а-дихлорид составляет 1 Гр; в красном костном мозге — 0,14 Гр. Однако использованный подход не учитывает специфического накопления радиофармпрепарата в метастазах, что может приводить к значительной переоценке поглощенной дозы в здоровой части поверхности кости и красного костного мозга

Patient organ and effective dose estimation in radionuclide therapy with ²²³Ra -dichloride

Radionuclide therapy with 223Ra-dichloride is used to treat bone metastases and to improve the quality of life of patients with metastatic castration-resistant prostate cancer. At the present time there is no reliable data on the biodistribution of the 223Ra-dichloride in the patient body. The aim of this study was to assess absorbed, equivalent doses in radiosensitive organs and tissues and effective dose from internal exposure for patients with metastatic castration-resistant prostate cancer treated with 223Ra-dichloride. Internal doses from 223Ra-dichloride were calculated for a chamber model specific for patients with metastatic castration-resistant prostate cancer. This model consists of 8 chambers (blood plasma, two chambers describing bone tissue, small intestine, upper large intestine, lower large intestine, feces and the rest of the body). Time-integrated activities were calculated using the SAAM II v2.3 software. The IDAC-Dose 2.1 software was used to calculate the absorbed doses. The highest absorbed doses in organs and equivalent doses were determined for the bone surface and red bone marrow. The absorbed dose from a-radiation in the bone surface for a set of six therapeutic procedures with 223Ra-dichloride was estimated as 1 Gy; in the red bone marrow — 0.14 Gy. However, the approach used does not specifically consider accumulation of the radiopharmaceutical in metastases, which can lead to a significant overestimation of the absorbed dose in the healthy part of the bone surface and red bone marrow