ABSTRACT
Objective To evaluate the effect of dexmedetomidine pretreatment on expression of se-cretion protein of Clara cell secretory protein(CC16)during endotoxin-induced acute lung injury(ALI) in rats.Methods One hundred and twelve healthy Wistar rats of both sexes, aged 8-12 weeks, weighing 250-350 g, were divided into ALI group(n=56)and dexmedetomidine pretreatment group(group DEX, n= 56)using a random number table.ALI was induced by intravenously injecting lipopolysaccharide (LPS)5 mg∕kg over 1 min.Dexmedetomidine 10 μg∕kg was intravenously infused over 10 min starting from 10 min before LPS in group DEX.At 10 min before LPS injection and 0.5, 1, 2, 4, 6 and 24 h after LPS injection, 8 rats were sacrificed and lungs were removed for examination of the pathological changes(with a light microscope)and ultrastructure of Clara cells(with a transmission electron microscope)and for deter-mination of CC16 expression in bronchioles(by immunohistochemistry). Results Compared with the baseline at 10 min before LPS injection, the expression of CC16 in bronchioles was significantly down-regu-lated at 1, 2, 4, 6 and 24 h after LPS injection in group ALI and at 1, 2, 4 and 6 h after LPS injection in group DEX(P<0.01), the pulmonary small arterial hyperemia, alveolar septa edema, red blood cell exudation and inflammatory cell infiltration were found, the Clara cells in bronchioles were reduced, the secretory granules in the cytoplasm were reduced, and the mitochondria were swollen and deformed after in-jection of LPS.Compared with group ALI, the expression of CC16 in bronchioles was significantly up-regu-lated at 1, 2, 4, 6 and 24 h after LPS injection(P<0.01), the pathologic changes of lung tissues were significantly attenuated, and the number of Clara cells was increased in group DEX.Conclusion The mechanism by which dexmedetomidine pretreatment reduces endotoxin-induced ALI may be related to up-regulating CC16 expression in rats.
ABSTRACT
BACKGROUND: Later Pleistocene human evolution in East Asia remains poorly understood owing to a scarcity of well described, reliably classified and accurately dated fossils. Southwest China has been identified from genetic research as a hotspot of human diversity, containing ancient mtDNA and Y-DNA lineages, and has yielded a number of human remains thought to derive from Pleistocene deposits. We have prepared, reconstructed, described and dated a new partial skull from a consolidated sediment block collected in 1979 from the site of Longlin Cave (Guangxi Province). We also undertook new excavations at Maludong (Yunnan Province) to clarify the stratigraphy and dating of a large sample of mostly undescribed human remains from the site. METHODOLOGY/PRINCIPAL FINDINGS: We undertook a detailed comparison of cranial, including a virtual endocast for the Maludong calotte, mandibular and dental remains from these two localities. Both samples probably derive from the same population, exhibiting an unusual mixture of modern human traits, characters probably plesiomorphic for later Homo, and some unusual features. We dated charcoal with AMS radiocarbon dating and speleothem with the Uranium-series technique and the results show both samples to be from the Pleistocene-Holocene transition: â¼14.3-11.5 ka. CONCLUSIONS/SIGNIFICANCE: Our analysis suggests two plausible explanations for the morphology sampled at Longlin Cave and Maludong. First, it may represent a late-surviving archaic population, perhaps paralleling the situation seen in North Africa as indicated by remains from Dar-es-Soltane and Temara, and maybe also in southern China at Zhirendong. Alternatively, East Asia may have been colonised during multiple waves during the Pleistocene, with the Longlin-Maludong morphology possibly reflecting deep population substructure in Africa prior to modern humans dispersing into Eurasia.
