Optimized regional and interannual variability of lightning in a global chemical transport model constrained by LIS/OTD satellite data

Nitrogen oxides (NOx≡ NO + NO2) produced by lightning make a major contribution to the global production of tropospheric ozone and OH. Lightning distributions inferred from standard convective parameterizations in global chemical transport models (CTMs) fail to reproduce observations from the Lightning Imaging Sensor (LIS) and the Optical Transient Detector (OTD) satellite instruments. We present an optimal regional scaling algorithm for CTMs to fit the lightning NOx source to the satellite lightning data in a way that preserves the coupling to deep convective transport. We show that monthly scaling using ~35 global regions significantly improves the tropical ozone simulation in the GEOS-Chem CTM as compared to a simulation unconstrained by the satellite data, and performs equally well to a simulation with local scaling. The coarse regional scaling preserves sufficient statistics in the satellite data to constrain the interannual variability (IAV) of lightning. After processing the LIS data to remove its diurnal sampling bias, we construct a monthly time series of lightning flash rates for 1998-2010 and 35ºS-35ºN. We find a correlation of IAV in tropical lightning with El Niño but not with the solar cycle or the quasi-biennial oscillation. The resulting global lightning NOx source in GEOS-Chem is 6.0 ± 0.5 Tg N a-1, compared to 5.5 ± 0.8 Tg N a-1 for the biomass burning source. Lightning NOx could have a large influence on the IAV of tropospheric ozone because it is released in the upper troposphere where ozone production is most efficient.Engineering and Applied Science

Loss of Sialic Acid Binding Domain Redirects Protein σ1 to Enhance M Cell-Directed Vaccination

Ovalbumin (OVA) genetically fused to protein sigma 1 (pσ1) results in tolerance to both OVA and pσ1. Pσ1 binds in a multi-step fashion, involving both protein- and carbohydrate-based receptors. To assess the relative pσ1 components responsible for inducing tolerance and the importance of its sialic binding domain (SABD) for immunization, modified OVA-pσ1, termed OVA-pσ1(short), was deleted of its SABD, but with its M cell targeting moiety intact, and was found to be immunostimulatory and enhanced CD4+ and CD8+ T cell proliferation. When used to nasally immunize mice given with and without cholera toxin (CT) adjuvant, elevated SIgA and serum IgG responses were induced, and OVA-pσ1(s) was more efficient for immunization than native OVA+CT. The immune antibodies (Abs) were derived from elevated Ab-forming cells in the upper respiratory tissues and submaxillary glands and were supported by mixed Th cell responses. Thus, these studies show that pσ1(s) can be fused to vaccines to effectively elicit improved SIgA responses

Ozone and organic nitrates over the eastern United States: Sensitivity to isoprene chemistry

We implement a new isoprene oxidation mechanism in a global 3-D chemical transport model (GEOS-Chem). Model results are evaluated with observations for ozone, isoprene oxidation products, and related species from the International Consortium for Atmospheric Research on Transport and Transformation aircraft campaign over the eastern United States in summer 2004. The model achieves an unbiased simulation of ozone in the boundary layer and the free troposphere, reflecting canceling effects from recent model updates for isoprene chemistry, bromine chemistry, and HO2 loss to aerosols. Simulation of the ozone-CO correlation is improved relative to previous versions of the model, and this is attributed to a lower and reversible yield of isoprene nitrates, increasing the ozone production efficiency per unit of nitrogen oxides (NO_x ≡ NO + NO_2). The model successfully reproduces the observed concentrations of organic nitrates (∑ANs) and their correlations with HCHO and ozone. ∑ANs in the model is principally composed of secondary isoprene nitrates, including a major contribution from nighttime isoprene oxidation. The correlations of ∑ANs with HCHO and ozone then provide sensitive tests of isoprene chemistry and argue in particular against a fast isomerization channel for isoprene peroxy radicals. ∑ANs can provide an important reservoir for exporting NO_x from the U.S. boundary layer. We find that the dependence of surface ozone on isoprene emission is positive throughout the U.S., even if NO_x emissions are reduced by a factor of 4. Previous models showed negative dependences that we attribute to erroneous titration of OH by isoprene

Флуоресцентная диагностика с хлорином е6 в хирургии глиом низкой степени злокачественности

Intraoperative fluorescence diagnostics of high-grade gliomas is widely used in neurosurgical practice. This work analyzes the possibilities of fluorescence diagnostics for low-grade gliomas (LGG) using chlorin e6 photosensitizer. The study included patients with newly diagnosed LGG, for whom chlorin e6 was used for intraoperative fluorescence control at a dose of 1 mg/kg. During the operation, the fluorescence intensity of various areas of the putative tumor tissue was analyzed using the RSS Cam – Endo 1.4.313 software. Tissue samples with various degrees of fluorescence intensity were compared with the results of their histopathological analysis (WHO tumor diagnosis, Ki-67 index, P53, VEGF). Fluorescence was detected in more than half of the cases, but in most cases had a focal character and low fluorescence intensity. The fluorescence intensity directly correlated with the data of histopathological examination of tumor tissues (Ki-67 index (p=0.002), expression of P53 (p=0.0015) and VEGF (p=0.001)). The sensitivity of the method for LGG surgery was 72%, the specificity was 56,7%. Intraoperative fluorescence diagnostics with chlorin e6 can be used in LGG surgery, especially to visualize intratumoral areas with a higher degree of anaplasia.Применение интраоперационной флуоресцентной диагностики для глиом высокой степени злокачественности широко используется в нейрохирургической практике. В работе проанализированы возможности флуоресцентной диагностики для глиом низкой степени злокачественности с использованием хлорина е6. В исследование были включены пациенты с впервые диагностированной глиомой низкой степени злокачественности (low-grade glioma, LGG), у которых с целью интраоперационного флуоресцентного контроля применен препарат хлорин е6 в дозе 1 мг/кг массы тела. В процессе операции анализировали интенсивность флуоресценции различных участков предполагаемой опухолевой ткани с использованием программного обеспечения RSS Cam – Endo 1.4.313. Образцы тканей различной степени интенсивности флуоресценции сопоставляли с результатами их гистопатологического анализа (диагностика опухоли ВОЗ, индекс Ki-67, P53, VEGF). Флуоресценция выявлена в более чем половине случаев, но в большинстве случаев имела очаговый характер и низкую интенсивность флуоресценции. Интенсивность флуоресценции напрямую коррелировала с данными гистопатологического исследования тканей опухоли: индекс Ki-67 (p=0,002), экспрессия P53 (p=0,0015), VEGF (p=0,001). Чувствительность метода для хирургии LGG составила 72%, специфичность 56,7%. Проведенное исследование подтвердило, что технология интраоперационной флуоресцентной диагностики с применением хлорина е6 может применяться в хирургии LGG, особенно для визуализации внутриопухолевых участков с более высокой степенью анаплазии

Multiple Myeloma with Intracranial Distribution

Multiple myeloma (MM) is a malignant immunoproliferative disease involving plasma cells, leading to their malignant proliferation and the production of monoclonal paraproteins. Intracranial tumor spread in MM is very rare. This is a unique and infrequent localization, which makes it difficult to diagnose the disease. We report a rare case of treatment of a patient with MM intracranial spread, whose disease was presumably in remission and recurred as an intracranial plasmacytoma with a clinical picture of acute cerebrovascular accident. Surgical intervention was performed to remove the tumor, a histopathological analysis of the removed tissue was carried out. Even with early diagnosis, the prognosis remains bleak, with median survival rates of 3 to 6 months. However, aggressive multimodal treatment can prolong life by months

Inventory of Boreal Fire Emissions for North America in 2004: The Importance of Peat Burning and Pyro-Convective Injection

The summer of 2004 was one of the largest fire seasons on record for Alaska and western Canada. We construct a daily bottom-up fire emission inventory for that season, including consideration of peat burning and high-altitude (buoyant) injection, and evaluate it in a global chemical transport model (the GEOS-Chem CTM) simulation of CO through comparison with MOPITT satellite and ICARTT aircraft observations. The inventory is constructed by combining daily area burned reports and MODIS fire hot spots with estimates of fuel consumption and emission factors based on ecosystem type. We estimate the contribution from peat burning using drainage and peat distribution maps for Alaska and Canada; 17% of the reported 5.1 × 106 ha burned were located in peatlands in 2004. Our total estimate of North American fire emissions during the summer of 2004 is 30 Tg CO, including 11 Tg from peat. Including peat burning in the GEOS-Chem simulation improves agreement with MOPITT observations. The long-range transport of fire plumes observed by MOPITT suggests that the largest fires injected a significant fraction of their emissions in the upper troposphere.Earth and Planetary SciencesEngineering and Applied Science

Concentrations and Sources of Organic Carbon Aerosol in the Free Troposphere over North America

Aircraft measurements of water-soluble organic carbon (WSOC) aerosol over NE North America during summer 2004 (ITCT-2K4) are simulated with a global chemical transport model (GEOS-Chem) to test our understanding of the sources of organic carbon (OC) aerosol in the free troposphere (FT). Elevated concentrations were observed in plumes from boreal fires in Alaska and Canada. WSOC aerosol concentrations outside of these plumes average 0.9 ± 0.9 μg C m−3 in the FT (2–6 km). The corresponding model value is 0.7 ± 0.6 μg C m−3, including 42% from biomass burning, 36% from biogenic secondary organic aerosol (SOA), and 22% from anthropogenic emissions. Previous OC aerosol observations over the NW Pacific in spring 2001 (ACE-Asia) averaged 3.3 ± 2.8 μg C m−3 in the FT, compared to a model value of 0.3 ± 0.3 μg C m−3. WSOC aerosol concentrations in the boundary layer (BL) during ITCT-2K4 are consistent with OC aerosol observed at the IMPROVE surface network. The model is low in the boundary layer by 30%, which we attribute to secondary formation at a rate comparable to primary anthropogenic emission. Observed WSOC aerosol concentrations decrease by a factor of 2 from the BL to the FT, as compared to a factor of 10 decrease for sulfate, indicating that most of the WSOC aerosol in the FT originates in situ. Despite reproducing mean observed WSOC concentrations in the FT to within 25%, the model cannot account for the variance in the observations (R = 0.21). Covariance analysis of FT WSOC aerosol with other measured chemical variables suggests an aqueous-phase mechanism for SOA generation involving biogenic precursors.Earth and Planetary SciencesEngineering and Applied Science

Ozone-CO Correlations Determined by the TES Satellite Instrument in Continental Outflow Regions

Collocated measurements of tropospheric ozone (O3) and carbon monoxide (CO) from the Tropospheric Emission Spectrometer (TES) aboard the EOS Aura satellite provide information on O3-CO correlations to test our understanding of global anthropogenic influence on O3. We examine the global distribution of TES O3-CO correlations in the middle troposphere (618 hPa) for July 2005 and compare to correlations generated with the GEOS-Chem chemical transport model and with ICARTT aircraft observations over the eastern United States (July 2004). The TES data show significant O3-CO correlations downwind of polluted continents, with dO3/dCO enhancement ratios in the range 0.4–1.0 mol mol−1 and consistent with ICARTT data. The GEOS-Chem model reproduces the O3-CO enhancement ratios observed in continental outflow, but model correlations are stronger and more extensive. We show that the discrepancy can be explained by spectral measurement errors in the TES data. These errors will decrease in future data releases, which should enable TES to provide better information on O3-CO correlations.Earth and Planetary SciencesEngineering and Applied Science

Summertime Influence of Asian Pollution in the Free Troposphere over North America

We analyze aircraft observations obtained during INTEX-A (1 July 14 - August 2004) to examine the summertime influence of Asian pollution in the free troposphere over North America. By applying correlation analysis and Principal Component Analysis (PCA) to the observations between 6-12 km, we find dominant influences from recent convection and lightning (13 percent of observations), Asia (7 percent), the lower stratosphere (7 percent), and boreal forest fires (2 percent), with the remaining 71 percent assigned to background. Asian airmasses are marked by high levels of CO, O3, HCN, PAN, acetylene, benzene, methanol, and SO4(2-). The partitioning of reactive nitrogen species in the Asian plumes is dominated by peroxyacetyl nitrate (PAN) (approximately 600 pptv), with varying NO(x)/HNO3 ratios in individual plumes consistent with different plumes ages ranging from 3 to 9 days. Export of Asian pollution in warm conveyor belts of mid-latitude cyclones, deep convection, and lifting in typhoons all contributed to the five major Asian pollution plumes. Compared to past measurement campaigns of Asian outflow during spring, INTEX-A observations display unique characteristics: lower levels of anthropogenic pollutants (CO, propane, ethane, benzene) due to their shorter summer lifetimes; higher levels of biogenic tracers (methanol and acetone) because of a more active biosphere; as well as higher levels of PAN, NO(x), HNO3, and O3 (more active photochemistry possibly enhanced by injection of lightning NO(x)). The high delta O3/delta CO ratio (0.76 mol mol(exp -1)) of Asian plumes during INTEX-A is due to a combination of strong photochemical production and mixing with stratospheric air along isentropic surfaces. The GEOS-Chem global chemical transport model captures the timing and location of the Asian plumes remarkably well. However, it significantly underestimates the magnitude of the enhancements

Фотодинамическая терапия в нейроонкологии

Literature review reflects the current status and development status of intraoperative photodynamic therapy in neurooncology and discusses the results of the most important studies on photodynamic  therapy (PDT). We searched the Pubmed, EMBASE, Cochrane Library and eLibrary data-bases for publications  published  between January 2000 and December 2022. Found 204 publications  in foreign sources and 59 publications  in domestic editions, dealing with the issues of photodynamic  therapy in neurooncology. An analysis of the literature has shown that intraoperative PDT in neurooncology is an important tool that contributes to increasing the radicality of the operation and local control. The basic rationale for the effectiveness of PDT lies in the study of the pathways leading to the complete devitalization of a malignant tumor, the study of the mechanisms of the local and systemic immune response. In addition, subcellular targets in PDT are determined by the properties of photosensitizers (PS). Second generation PSs have already been introduced into clinical practice. The effectiveness of PDT using photoditazine, 5-aminolevulinic acid has been demonstrated. The mechanisms of action and targets of these PS have been established. In Russia, a number of studies have repeatedly shown and proved the clinical effectiveness of PDT in groups of neurooncological patients with glial tumors and secondary metastatic tumors, but so far, the method has not been included in the clinical guidelines for the provision of high-tech neurosurgical care. There is certainly a need for further development of PTD techniques in neurooncology, especially in patients at high risk of recurrence and aggressive CNS tumors.Выполнен обзор литературы, отражающий современное состояние и степень разработанности  методики интраоперационной  фотодинамической терапии (ФДТ) в нейроонкологи. Представлены к обсуждению результаты наиболее значимых исследований, посвященных ФДТ в нейроонкологии. Проведен анализ научных публикаций по данной тематике в базах данных Pubmed, EMBASE, Cochrane Library и eLibrary, опубликованных в промежуток времени с января 2000 г. по декабрь 2022 г. Найдено 204 публикации в зарубежных источниках  и 59 публикаций в отечественных  изданиях, в которых рассматриваются  вопросы применения ФДТ в нейроонкологии. Анализ литературы показал, что в клинической практике интраоперационная  ФДТ в нейроонкологии  является важным инструментом, способствующим увеличению радикальности операции и локального контроля. Фундаментальное обоснование эффективности ФДТ заключается в изучении путей, ведущих к полной девитализации злокачественной  опухоли, изучении механизмов локального и системного  иммунного ответа. При этом субклеточные  мишени при ФДТ обусловлены свойствами  фотосенсибилизаторов (ФС). В многочисленных  исследованиях  показана противоопухолевая эффективность  использования  ФДТ с ФС на основе  хлорина  е6, 5-аминолевулиновой  кислоты, производных  порфиринов.  Установлены механизмы действия и мишени этих ФС. В России  в ряде исследований подтверждена клиническая эффективность  ФДТ у групп нейроонкологических пациентов с глиальным опухолями и вторичными метастатическими опухолями, однако до сих пор метод не включён в клинические рекомендации по оказанию высокотехнологичной  нейрохирургической помощи. Безусловно, необходима дальнейшая разработка методики ФДТ в нейроонкологии, особенно у пациентов с высоким риском рецидива и агрессивными опухолями ЦНС