Optimal Surgical Options for Descending Necrotizing Mediastinitis of the Anterior Mediastinum

The mortality rates from descending necrotizing mediastinitis (DNM) are between 25 and 40 % mainly because of delayed diagnosis and inappropriate surgical treatment. This study was undertaken to examine two surgical options for DNM and determine the optimal surgical option for DNM of the anterior mediastinum. Fifteen cases of DNM of the anterior mediastinum, January 2001 and October 2010, were retrospectively reviewed. Eleven were anterosuperior mediastinitis, with infection located above the tracheal bifurcation and four had infections involving the entire anterior mediastinum. Depending on the location of mediastinitis, open drainage of the submandibular and neck abscesses, in addition to other surgical treatments, was performed. If the infection was anterosuperior, transcervical mediastinal drainage or thoracotomy was performed. If the entire anterior mediastinum was involved, necrotic tissue was removed with thoracoscopic via subxiphoid incision, the bilateral pleurae were opened for drainage, and a tunnel connecting the neck incision and the subxiphoid incision through the whole anterior mediastinum was made for drainage. The anterosuperior mediastinitis cases were treated with either transcervical mediastinal drainage (n = 8) or thoracotomy (n = 3). Patients healed after an average of 24.5 and 20.0 days in the hospital, respectively. For the four other cases, one patient died of septic shock, while the other three patients were healed after and an average of 43.3 days in the hospital. Mortality rate was 6.7 %. The surgical procedure used to treat DNM should be selected according to the location of the infection. DNM involving the anterosuperior mediastinum can be treated by transcervical mediastinal drainage. If anterosuperior mediastinitis spreads to the side of the trachea, open thoracotomy is a suitable therapy. If the entire anterior mediastinum is involved, debridement and drainage of the anterior mediastinum should be performed with a thoracoscope via the subxiphoid incision.     

SLC17A9 Protein Functions as a Lysosomal ATP Transporter and Regulates Cell Viability

Lysosomes contain abundant ATP, which is released through lysosomal exocytosis following exposure to various stimuli. However, the molecular mechanisms underlying lysosomal ATP accumulation remain unknown. The vesicular nucleotide transporter, also known as solute carrier family 17 member 9 (SLC17A9), has been shown to function in ATP transport across secretory vesicles/granules membrane in adrenal chromaffin cells, T cells, and pancreatic cells. Here, using mammalian cell lines, we report that SLC17A9 is highly enriched in lysosomes and functions as an ATP transporter in those organelles. SLC17A9 deficiency reduced lysosome ATP accumulation and compromised lysosome function, resulting in cell death. Our data suggest that SLC17A9 activity mediates lysosomal ATP accumulation and plays an important role in lysosomal physiology and cell viability.     

Indomethacin Treatment Prevents High Fat Diet-induced Obesity and Insulin Resistance but Not Glucose Intolerance in C57BL/6J Mice

Chronic low grade inflammation is closely linked to obesity-associated insulin resistance. To examine how administration of the anti-inflammatory compound indomethacin, a general cyclooxygenase inhibitor, affected obesity development and insulin sensitivity, we fed obesity-prone male C57BL/6J mice a high fat/high sucrose (HF/HS) diet or a regular diet supplemented or not with indomethacin (±INDO) for 7 weeks. Development of obesity, insulin resistance, and glucose intolerance was monitored, and the effect of indomethacin on glucose-stimulated insulin secretion (GSIS) was measured in vivo and in vitro using MIN6 β-cells. We found that supplementation with indomethacin prevented HF/HS-induced obesity and diet-induced changes in systemic insulin sensitivity. Thus, HF/HS+INDO-fed mice remained insulin-sensitive. However, mice fed HF/HS+INDO exhibited pronounced glucose intolerance. Hepatic glucose output was significantly increased. Indomethacin had no effect on adipose tissue mass, glucose tolerance, or GSIS when included in a regular diet. Indomethacin administration to obese mice did not reduce adipose tissue mass, and the compensatory increase in GSIS observed in obese mice was not affected by treatment with indomethacin. We demonstrate that indomethacin did not inhibit GSIS per se, but activation of GPR40 in the presence of indomethacin inhibited glucose-dependent insulin secretion in MIN6 cells. We conclude that constitutive high hepatic glucose output combined with impaired GSIS in response to activation of GPR40-dependent signaling in the HF/HS+INDO-fed mice contributed to the impaired glucose clearance during a glucose challenge and that the resulting lower levels of plasma insulin prevented the obesogenic action of the HF/HS diet.     

Scorpion Venom Heat-Resistant Peptide (SVHRP) Enhances Neurogenesis and Neurite Outgrowth of Immature Neurons in Adult Mice by Up-Regulating Brain-Derived Neurotrophic Factor (BDNF)

Scorpion venom heat-resistant peptide (SVHRP) is a component purified from Buthus martensii Karsch scorpion venom. Although scorpions and their venom have been used in Traditional Chinese Medicine (TCM) to treat chronic neurological disorders, the underlying mechanisms of these treatments remain unknown. We applied SVHRP in vitro and in vivo to understand its effects on the neurogenesis and maturation of adult immature neurons and explore associated molecular mechanisms. SVHRP administration increased the number of 5-bromo-2’-dexoxyuridine (BrdU)-positive cells, BrdU- positive/neuron-specific nuclear protein (NeuN)-positive neurons, and polysialylated-neural cell adhesion molecule (PSA-NCAM)-positive immature neurons in the subventricular zone (SVZ) and subgranular zone (SGZ) of hippocampus. Furthermore immature neurons incubated with SVHRP-pretreated astrocyte-conditioned medium exhibited significantly increased neurite length compared with those incubated with normal astrocyte-conditioned medium. This neurotrophic effect was further confirmed in vivo by detecting an increased average single area and whole area of immature neurons in the SGZ, SVZ and olfactory bulb (OB) in the adult mouse brain. In contrast to normal astrocyte-conditioned medium, higher concentrations of brain-derived neurotrophic factor (BDNF) but not nerve growth factor (NGF) or glial cell line-derived neurotrophic factor (GDNF) was detected in the conditioned medium of SVHRP-pretreated astrocytes, and blocking BDNF using anti-BDNF antibodies eliminated these SVHRP-dependent neurotrophic effects. In SVHRP treated mouse brain, more glial fibrillary acidic protein (GFAP)-positive cells were detected. Furthermore, immunohistochemistry revealed increased numbers of GFAP/BDNF double-positive cells, which agrees with the observed changes in the culture system. This paper describes novel effects of scorpion venom-originated peptide on the stem cells and suggests the potential therapeutic values of SVHRP.     

Study of the relationship between compositions of shrub plant of stable-carbon-isotope and environmental factors in Xinjiang representatives of Chenopodiaceae

The paper analyses total of 58 samples representing 32 species of the 14 genera of shrub plant of the carbon isotope composition in Xinjiang representatives of Chenopodiaceae and a detailed discussion on the various factors that can influence them. The value of 38 samples fall between ?14.88‰ and ?11.55‰ with a mean of ?13.34‰, and values of 20 samples between ?27.93‰ and ?22.877‰ with a mean of ?25.38‰. So we obtained a total of 21 of C4 species (59.4%) and 11 of C3 species (40.6%) from 32 species studied Chenopodiaceae of shrubs plant. Then the relationship of plant-carbon-isotope and environmental factors has been analyzed. The results showed that the importance environmental factors for the δ¹³C-value of the Shrubs was annual precipitation (0.78) > temperature (0.66) > elevation (0.55). The three principal components has important factors to influence on C₃/C₄ shrub plant distribution. Environmental conditions play significant roles in the distribution and ecophysiological features of different photosynthetic types and even change the photosynthetic pathways. On the other hand, such as geographic location, Sunshine duration, evaporation capacity are more or less correlation with δ¹³C values, however, they would be interfered by annual precipitation. Desert plants to adapt to drought conditions by increasing water use efficiency (WUE) strategy. In short, plant physiology function is sensitive and timely to adapt environmental change.     

Evolutionary history of a widespread tree species Acer mono in East Asia

East Asia has the most diverse temperate flora in the world primarily due to the lack of Pleistocene glaciation and the geographic heterogeneity. Although increasing phylogeography studies in this region provided more proofs in this issue, discrepancies and uncertainty still exist, especially in northern temperate deciduous broad‐leaved and coniferous mixed forest region (II). And a widespread plant species could reduce the complexity to infer the relationship between diversity and physiographical pattern. Hence, we studied the evolution history of a widespread temperate tree, Acer mono, populations in region II and the influence of physiographic patterns on intraspecific genetic diversity. Analyses of chloroplast sequences and nuclear microsatellites indicated high levels of genetic diversity. The diversity distribution was spatially heterogeneous and a latitudinal cline existed in both markers. The spatial distribution pattern between genetic diversity within A. mono and the diversity at species level was generally consistent. Western subtropical evergreen broad‐leaved forest subregion (IVb) had a unique ancient chloroplast clade (CP3) and a nuclear gene pool (GP5) with dominance indicating the critical role of this area in species diversification. Genetic data and ecological niche model results both suggested that populations in region II disappeared during the last glacial maximum (LGM) and recovered from south of Changbai Mt. and the Korean Peninsula. Two distribution centers were likely during the LGM, one in the north edge of warm temperate deciduous broad‐leaved forest region (III) and another in the south edge of region III. This was reflected by the genetic pattern with two spatially independent genetic groups. This study highlights the key role of region III in sustaining genetic diversity in the northern range and connecting diversity between southern and northern range. We elucidated the diversity relationship between vegetation regions which could facilitate the understanding of biodiversity origin and maintenance in East Asia.     

干旱区荒漠稀疏植被覆盖度提取及尺度扩展效应

选择线性混合像元分解模型、亚像元模型、最大三波段梯度差法模型以及修正的三波段梯度差法的2个变异模型来提取植被覆盖度,结合地面实测数据,探讨了提取干旱区荒漠稀疏植被覆盖度信息的适宜模型,并以简单平均法模拟了不同尺度的覆盖度影像,通过尺度上推检验了模型在MODIS尺度上的反演效应.结果表明：线性混合像元分解模型反演覆盖度的精度高于其他模型,适于稀疏植被地区,但端元的正确选取较难,从而影响其运用;亚像元分解模型是一个通用模型,植被分类图越精细,通过亚像元分解模型得到的覆盖度精度越高,但这也同时意味着该模型需要测定大量的输入参数;最大三波段梯度差法的算法简单、易于操作,其在农田等中高植被覆盖区及裸土区的预测值与实测值接近,但对干旱区稀疏植被的估计精度偏低;修正后的三波段最大梯度差法模型在稀疏植被覆盖区的预测值与实测值基本一致,在不同尺度上反演的覆盖度信息与实测值的一致性较好.该方法可有效提取干旱区低覆盖度植被信息.     

西藏藏族青少年体型

为了探讨藏族青少年体型发育特征及其规律, 本文应用Heath-Carter体型法对2530名藏族青少年体型进行评价。结果发现, 藏族青少年的平均体型男性为偏中胚层的外胚层型(2.40—3.29—3.72),女性为中间型(3.65—2.87—3.32); 男性的体型以外胚层系体型为主(58.52%), 女性体型以内胚层系(32.62%)和外胚层系为主(35.40%); 随着年龄的增长, 藏族青少年的体型发展有一定的规律, 男性由中胚层-外胚层均衡型经偏中胚层的外胚层型又发展回中胚层-外胚层均衡型, 女性由中胚层-外胚层均衡型经历均衡的外胚层型发展为均衡的内胚层型。因此, 本文认为,藏族男性青少年身体的线性程度高、外形上比较瘦削、肌肉较发达; 藏族女性青少年较男性身体的脂肪含量多、线性程度相对较高。     

废啤酒酵母吸附水溶液中Cu2+的性能及机理研究

用废啤酒酵母吸附水溶液中Cu2+,考察了溶液pH值、Cu2+浓度和吸附时间对Cu2+吸附的影响。结果表明：废啤酒酵母吸附Cu2+在4-6个小时内达到吸附平衡,酸性条件利于吸附,以pH为5时最佳,吸附等温曲线符合Langmuir模式。用电位滴定及FTIR分析的方法确定生物吸附剂主要含有磺酸基、羧基及氨基等功能团。生物吸附剂对Cu2+的吸附以单分子层的化学吸附为主,功能团在不同的pH条件下呈现不同的电离性能,在吸附过程中发挥重要作用。