异一枝蒿酮酸的结构

从新疆一枝蒿(Artemisia rupestris L.)中分得一个新成分,命名为异一枝蒿酮酸(isorupestonic acid),根据光谱(IR,UV,MS.NMR),X-ray晶体衍射及CD谱分析,确定其结构及绝对构型。并经X-ray晶体衍射及CD谱分析修正了一枝蒿酮酸的绝对构型。     

新疆一枝蒿新倍半萜成分——一枝蒿酮酸的结构

从新疆一枝蒿(Artemisia rupestris L.)脂溶性部分分得一种新倍半萜晶体,根据紫外光谱,红外光谱、质谱,核磁共振氢谱及碳谱等分析,确定了结构,命名为一枝蒿酮酸。     

人卵促性腺激素释放肽（hF－GRP）及其类似物合成和生物活性初探

用固相法合成了ｈＦ－ＧＲＰ及其１５个类似物。全部裂解均用三氟甲磺酸完成。产物总收率６０％～８０％。对所有合成肽进行了影响离体的小鼠垂体分泌ＬＨ的活性筛选。结果表明，当合成肽的浓度为０．０５ｍｍｏｌ／Ｌ时：（１）将ｈＦ－ＧＲＰ的Ｃ端ＣＯＯＨ变成ＣＯＮＨ２，活性变化不大；（２）Ｃ端残基Ａｓｎ１４被Ｐｈｅ替换后刺激垂体分泌ＬＨ的活性明显高于ｈＦ－ＧＲＰ；（３）Ｔｈｒ３被Ｔｙｒ替换后片段ｈＦ－ＧＲＰ（３～１３）有抑制ＬＨ分泌的活性；（４）其余类似物与空白对照相似。     

固相法合成心肌兴奋肽及其类似物

用Boc-和Tos-基团分别保护氨基和侧链胍基,以1%交联度聚苯乙烯二苯甲氨基树脂为载体,用DCC固相法合成肽,HF断裂肽树脂键和去除侧链保护基团,粗产物经高效液相层析纯化,合成了心肌兴奋肽Phe-Met-Arg-Phe-NH_2及其类似物Phe-Pro-Arg-Phe-NH_2,并观察了此二种肽对大鼠血压和心率的影响。     

Does the publication of NICE guidelines for venous thromboembolism chemical prophylaxis influence the prescribing patterns of UK hip and knee surgeons?

IntroductionWe assessed the practice of surgeons regarding venous thromboembolism (VTE) chemical prophylaxis for total hip replacement (THR) and total knee replacement (TKR), before and after issuing of updated National Institute for Health and Care Excellence (NICE) guidance in 2018.MethodsA survey, circulated through the British Hip Society and regional trainee networks/collaboratives, was completed by 306 UK surgeons at 187 units. VTE chemical prophylaxis prescribing patterns for surgeons carrying out primary THR (n=258) and TKR (n=253) in low-risk patients was assessed after publication of 2018 NICE recommendations. Prescribing patterns before and after the NICE publication were subsequently explored.ResultsFollowing the new guidance, 34% (n=87) used low-molecular-weight heparin (LMWH) alone, 33% (n=85) aspirin (commonly preceded by LMWH) and 31% (n=81) direct oral anticoagulants (DOACs: with/without preceding LMWH) for THR. For TKR, 42% (n=105) used aspirin (usually monotherapy), 31% (n=78) LMWH alone and 27% (n=68) DOAC (with/without preceding LMWH). NICE guidance changed the practice of 34% of hip surgeons and 41% of knee surgeons, with significantly increased use of aspirin preceded by LMWH for THR (before=25% vs after=73%; p<0.001), and aspirin for TKR (before=18% vs after=84%; p<0.001). Significantly more regimens were NICE guidance compliant after the 2018 update for THR (before=85.7% vs after=92.6%; p=0.011) and TKR (before=87.0% vs after=98.8%; p<0.001).ConclusionOver one-third of surveyed surgeons changed their VTE chemical prophylaxis in response to 2018 NICE recommendations, with more THR and TKR surgeons now compliant with latest NICE guidance. The major change in practice was an increased use of aspirin for VTE chemical prophylaxis.     

Management of tooth resorption

A correct diagnosis and an understanding of the aetiology and dynamics of the processes involved in tooth resorption is critical to effective management. Tooth resorptions can be classified as: (1) trauma induced; (2) infection induced; or (3) hyperplastic invasive. Some transient trauma induced resorptions require no treatment but must be carefully monitored to check that there are no complicating issues such as infection. In cases of trauma induced replacement resorption, a multidisciplinary approach is usually necessary to ensure an optimal long-term solution. Infection induced tooth resorptions require the removal of the invading micro-organisms by endodontic therapy including intra-canal medication which can also facilitate repair of the resorbed tooth structure. The hyperplastic invasive tooth resorptions pose considerable challenges in management due to the complexity and aggressive nature of the resorptive process. With careful case selection and complete inactivation of resorptive tissue successful management can be achieved.     

Randomised comparison of ondansetron and metoclopramide plus dexamethasone for chemotherapy induced emesis

The serotonin (5HT3) antagonist ondansetron was compared in a randomised study with metoclopramide and dexamethasone for the prevention of chemotherapy induced emesis. Thirty children aged 1-15 years with acute lymphoblastic leukaemia received 'intensification modules' according to the MRC United Kingdom acute lymphoblastic leukaemia regimen UKALL XI. This contains the moderately emetogenic drugs daunorubicin, etoposide, and cytarabine. Fifteen children received an intravenous loading dose of ondansetron followed by intravenous or oral doses 12 hourly for five days. Fifteen children received intravenous metoclopramide every six hours for three days with a loading dose of dexamethasone, repeated every eight hours for three days intravenously or orally. Efficacy was assessed by a diary card documenting the incidence of nausea, retching, or vomiting. In the 24 hour period after starting chemotherapy, ondansetron was more effective, with a complete or major response rate of 93%, compared with 33% using metoclopramide/dexamethasone.     

争光霉素A6和它在争光霉素复合物的地位

争光霉素A₅已鉴别为Bleomycin A₆,在争光霉素复合物中所占比例一般在10%左右,在某些批样中可高达15%以上。文献报告Bleomycin A₆在天然产的Bleomyein复合物中只有痕量。通过向发酵培养基中加入特定组分的末端胺可大大提高其特定组分在复合物中的含量比而其它组分的产生则不同程度地被抑制。但Bleomyein A₆例外,即使向培养基中加入其末端胺精胺(0.3mg/ml),在所产生的复合物中大大增多的组分是Bleomyein A₆,而Bleomycin A₆仍只有痕量。这表明争光霉素产生菌有和Bleomycin产生菌明显不同的特点。