The Tribolium chitin synthase genes TcCHS1 and TcCHS2 are specialized for synthesis of epidermal cuticle and midgut peritrophic matrix

Functional analysis of the two chitin synthase genes, TcCHS1 and TcCHS2, in the red flour beetle, Tribolium castaneum, revealed unique and complementary roles for each gene. TcCHS1-specific RNA interference (RNAi) disrupted all three types of moult (larval-larval, larval-pupal and pupal-adult) and greatly reduced whole-body chitin content. Exon-specific RNAi showed that splice variant 8a of TcCHS1 was required for both the larval-pupal and pupal-adult moults, whereas splice variant 8b was required only for the latter. TcCHS2-specific RNAi had no effect on metamorphosis or on total body chitin content. However, RNAi-mediated down-regulation of TcCHS2, but not TcCHS1, led to cessation of feeding, a dramatic shrinkage in larval size and reduced chitin content in the midgut.     

人表皮细胞与角膜上皮细胞蛋白质组的差异表达初步研究

目的：应用蛋白质组技术比较人表皮细胞与角膜上皮细胞之间的蛋白质表达差异。方法：实验于2005-11，2006-10在中山大学中山眼科中心国家眼科学重点实验室完成。分别培养人表皮细胞与角膜上皮细胞，裂解原代细胞抽提总蛋白，精确定量后进行双向电泳，扫描电泳凝胶获得二维总蛋白图谱。图谱使用软件辅助比较分析，找出差异表达点，从凝胶中抠取差异点，胶内酶解后用基质辅助激光解吸附，电离飞行时间串级质谱法鉴定差异蛋白。结果：人表皮细胞与角膜上皮细胞蛋白质凝胶分析获得600余个清晰的蛋白质斑点，在比较分析出的26个差异点中初步鉴定出4个差异表达蛋白，分别是细胞内氯离子通道1、Psodasin、乳酸脱氢酶B和丝氨酸蛋白酶抑制因子。结论：人表皮细胞与角膜上皮细胞在蛋白质表达上有较高的相似性以及较好的可比性，为探索表皮细胞横向分化成角膜上皮细胞的分子机制做出了有益的尝试，并提供了具有一定可操作性的实验方法。     

DIGITAL ISCHAEMIA: AN UNUSUAL PRESENTATION OF DYSBARISM

SUMMARY Dysbaric symptoms following ascent from a scuba dive are due to symptomatic nitrogen or air emboli with clear patterns of associated injury. This case report highlights an unusual presentation of dysbaric injury treated successfully with a prostacyclin analogue.     

Temporary anchorage device insertion variables: effects on retention

Objective:To quantify the influence of temporary anchorage device (TAD) insertion variables on implant retention.Materials and Methods:Three hundred thirty TADs from three companies were placed in synthetic bone replicas at variable depths and angulations and compared. Clinically relevant forces were applied to the TADs until failure of retention occurred.Results:In all three implants, increased insertion depth increased implant retention. As the distance from the abutment head to the cortical plate increased, the retention of all three implants decreased. A significantly greater force to fail was required for a 90° insertion angle than for 45° or 135° insertion angles. No significant difference was found between the 45° and 135° insertion angles. A significant reduction in force to fail occurred when comparing 90° and 45° oblique insertion angles.Conclusions:Increasing penetration depth of TADs results in greater retention. Increased abutment head distance from cortical plate leads to decreased retention. Placement of TADs at 90° to the cortical plate is the most retentive insertion angle. Insertion at an oblique angle from the line of force reduces retention of TADs.     

The Concept of Diminished Responsibility in Supranational Criminal Law (Psychiatric Approach)

The role of the community management order (CMO) in the management of mental illness has been associated with controversy. There is uncertainty as to the effectiveness of such involuntary treatment. Review of outcomes of involuntary community treatment has shown varied results, and in the remote areas of Australia the issue becomes more complex, and outcomes more difficult to measure. The Northern Territory's Mental Health Act 2000 has broadened criteria for detention. The decision to impose follow-up and case management on an individual (who may reside in a community several hundred kilometres from an in-patient facility) requires careful consideration of its ethical, professional and psychosocial implications. The trend toward increasing use of mental health legislation in the Northern Territory — particularly for Indigenous people — deserves close scrutiny in order that culturally appropriate and sensitive treatment plans are developed.