Oxysterol Binding Protein-dependent Activation of Sphingomyelin Synthesis in the Golgi Apparatus Requires Phosphatidylinositol 4-Kinase IIα

The study identifies a sterol- and oxysterol binding protein (OSBP)-regulated phosphatidylinositol 4-kinase that regulates ceramide transport protein (CERT) activity and sphingomyelin (SM) synthesis. RNA interference silencing experiments identify PI4KIIα; as the mediator of Golgi recruitment of CERT, providing a potential mechanism for coordinating assembly of SM and cholesterol in the Golgi or more distal compartments

Role of ER Stress Response in Photodynamic Therapy: ROS Generated in Different Subcellular Compartments Trigger Diverse Cell Death Pathways

We have analyzed the molecular mechanisms of photoinduced cell death using porphyrins with similar structure differing only in the position of the ethylene glycol (EG) chain on the phenyl ring. Meta- and para-positioned EG chains targeted porphyrins to different subcellular compartments. After photoactivation, both types of derivatives induced death of tumor cells via reactive oxygen species (ROS). Para derivatives pTPP(EG)4 and pTPPF(EG)4 primarily accumulated in lysosomes activated the p38 MAP kinase cascade, which in turn induced the mitochondrial apoptotic pathway. In contrast, meta porphyrin derivative mTPP(EG)4 localized in the endoplasmic reticulum (ER) induced dramatic changes in Ca2+ homeostasis manifested by Ca2+ rise in the cytoplasm, activation of calpains and stress caspase-12 or caspase-4. ER stress developed into unfolded protein response. Immediately after irradiation the PERK pathway was activated through phosphorylation of PERK, eIF2α and induction of transcription factors ATF4 and CHOP, which regulate stress response genes. PERK knockdown and PERK deficiency protected cells against mTPP(EG)4-mediated apoptosis, confirming the causative role of the PERK pathway

Sedimentation rates of fine aerosols in acoustic and electric field

Актуальность исследования связана с поиском эффективных способов осаждения мелкодисперсных аэрозолей с целью очистки производственных помещения от пыли и дыма. Развитие методов обеспечения чистоты воздушной среды в производственных помещениях особенно актуально в связи с применением нанотехнологий, а также химических технологий, связанных с возможными выбросами вредной и опасной пыли. Цель работы: поиск оптимальных способов осаждения мелкодисперсных аэрозолей при сравнении электростатического и ультразвукового способов осаждение частиц. Объекты: мелкодисперсные аэрозоли и способы их осаждения. Методы: математическое моделирование, оптические методы измерения функции распределения частиц по размерам и концентрации частиц аэрозоля с использованием лазерного измерительного комплекса ЛИД-2М и анализатора Malvern Spraytec. Результаты. Проведен теоретический анализ скоростей осаждения частиц мелкодисперсных аэрозолей (диаметр 1-20 мкм) в присутствии акустического, электрического поля с учетом дрейфа в электрическом поле, ультразвуковой коагуляции и акустических течений («звукового ветра»). Определены ведущие механизмы осаждения частиц в зависимости от их размера, что позволяет предложить оптимальные способы осаждения мелкодисперсных аэрозолей в каждом диапазоне размеров частиц. Математическая модель акустической коагуляции основана на интегральной форме уравнения Смолуховского. Представлены результаты экспериментального исследования осаждения частиц модельного аэрозоля (NaCl) с характерным диаметром частиц около 6 мкм с помощью ультразвука и с помощью электроосаждающего устройства. Установлено, что применение данных способов осаждения существенно ускоряет седиментацию модельного аэрозоля, что соответствует теоретическим результатам. С другой стороны, теоретические расчеты предсказывают, что по сравнению с ультразвуковым способом осаждения применение электростатического способа будет более эффективно для аэрозолей с относительно более крупными частицами.The relevance of the research is related to searching the efficient ways of deposition of fine aerosols to clean production rooms from dust and smoke. Development of methods of ensuring purity of air environment in production rooms are especially relevant in connection with the development of nanotechnologies as well as engineering chemistries, related to possible emissions of harmful and dangerous dust. The main aim of the research is searching for optimum ways of deposition of fine aerosols comparing electrostatic and ultrasonic deposition of particles. Objects of the research are fine aerosols and ways of their deposition. Methods: mathematical modeling, optical methods of measurement of distribution function of particles by the sizes and concentration of aerosol particles using the laser measuring system LID2M and the Malvern Spraytec analyzer. Results. The authors have carried out the theoretical analysis of sedimentation rates of particles of fine aerosols (diameter of particles ~1-20 µm) in the presence of acoustic, electric field taking into account a drift in electric field, ultrasonic coagulation, and acoustic flows («sound wind»). The key mechanisms of particles deposition depending on their size are defined that allows proposing the optimum ways of deposition of fine aerosols in each range of particle sizes. The mathematical model of acoustic coagulation is based on an integral form of the equation of Smolukhovsky. The paper introduces the results of the experimental study of the model aerosol (NaCl) particles deposition with the reference diameter of particles about 6 µm by means of ultrasound and electrodeposition device. It is defined that application of these ways of deposition is essential (and it is approximately identical) and it accelerates considerably sedimentation of the model aerosol that corresponds to theoretical results. On the other hand, theoretical calculations predict that application of electrostatic way of deposition will be more effective in comparison with the ultrasonic one for aerosols with rather larger particles

Diversidade de Lepidoptera (Papilionoidea e Hesperioidea) em dois fragmentos de floresta no município de Frederico Westphalen, Rio Grande do Sul, Brasil Diversity of Lepidoptera (Papilionoidea e Hesperioidea) in two fragments in Frederico Westphalen, Rio Grande do Sul State, Brazil

Foram realizados levantamentos mensais em duas localidades no Município, fragmento da Vila Faguense e do Santuário de Schoenstatt, os quais distam entre si em 1.500 m, entre março de 2005 e abril de 2006. Em 140 horas de amostragem foram registrados 3.123 indivíduos distribuídos em 169 espécies. Nymphalidae foi a família mais amostrada com aproximadamente 53% das espécies registradas. Nove espécies ainda não haviam sido registradas para o Estado. O índice de Diversidade de Shannon-Wiener foi maior no fragmento da Vila Faguense, local menos perturbado. Os índices de dominância de Simpson e Berger-Parker foram mais representativos no Santuário de Schoenstatt, com maior número de espécies abundantes. Foram registradas em Frederico Westphalen 126 (74,55%) espécies acidentais, 25 acessórias (14,80%) e 18 constantes (10,65%).<br>A systematic survey was carried out in two localities of the Municipal District of Frederico Westphalen, fragment of Villa Faguense and Schoenstatt's Sanctuary, situated 1,500 m apart, from March 2005 to April 2006. In 140 hours of sampling, 3123 individuals, distributed in 169 species, were registered. Nymphalidae was the most sampled with approximately 53% of the recorded species. Nine species sampled were still no registered for the State. The Shannon-Wiener diversity index was higher in fragment of Villa Faguense, place less disturbed. The Simpson and Berger-Parker dominance indexes had been more representative in fragment of Schoenstatt Sanctuary, with higher number of abundant species. Among the species captured 126 (74,55%) are accidental, 25 (14,80%) are accessory and 18 (10,65%) are constant