Monophasic transmitral flow pattern with less increase in heart rate indicates left ventricular dysfunction.

When heart rate (HR) increases, mitral flow can become monophasic. Prolonged isovolumic contraction and relaxation time (ICT and IRT), directly related to left ventricular (LV) function, can potentially influence the HR with monophasic mitral flow. The present study investigated the relation between HR that causes monophasic flow and LV function. During diagnostic catheterization, HR was increased using right atrial pacing by 2 beats/min every 2 min in a stepwise manner until the development of monophasic mitral flow in 17 patients with normal sinus rhythm. ICT, IRT, end-diastolic and end-systolic LV volumes, LV ejection fraction, LV peak + and -dP/dt, peak (+dP/dt)/P, and the relaxation time constant (tau) were measured by Doppler echocardiography or catheterization when monophasic mitral flow developed. The monophasic HR varied from 74 to 106 beats/min. By univariate analysis, ICT (p<0.01, r2=0.73), LV peak +dP/dt (p<0.05, r2=0.37), peak (+dP/dt)/P (p<0.01, r2=0.71), peak -dP/dt (p<0.05, r2=0.25), and tau (p<0.05, r2=0.33) had a significant correlation with monophasic HR. By multivariate analysis, prolonged ICT and reduced LV peak -dP/dt independently contributed to monophasic mitral flow with less increase in HR. Monophasic mitral flow with less increase in HR indicates impaired LV systolic and diastolic function during isovolumic contraction and relaxation.     

Diastolic pulmonary forward flow associated with pulmonary regurgitation demonstrated by Doppler echocardiography

To demonstrate diastolic pulmonary forward flow, pulsed and continuous wave Doppler echocardiograms were recorded in four patients with postoperative residual pulmonary stenosis and regurgitation (Group I). To clarify the mechanism, we further examined 24 patients with pulmonary regurgitation without diastolic pulmonary forward flow, including three patients with surgical correction of tetralogy of Fallot (Group IIa) and 21 patients with functional pulmonary regurgitation (Group IIb), and compared the peak velocity and pressure half time of pulmonary regurgitation among the three groups. Diastolic pulmonary forward flow was characterized as a flow signal which began after the abrupt cessation of pulmonary regurgitation and continued until the beginning of ejection flow. The onset of the flow coincided with that of premature opening of the pulmonary valve, and was following atrial contraction in one, before atrial contraction in two, and mid-diastolic in one. The velocity of diastolic pulmonary forward flow was increased during inspiration and its maximum velocity was 1.3 m/sec. Simultaneous recording of pressures and continuous wave Doppler echo performed in two patients in Group I showed the equalization of right ventricular and pulmonary artery pressures during the flow. There was no significant difference in the peak velocity of pulmonary regurgitation among the three groups of patients. The mean pressure half time was significantly shortened in patients in Group I (90 +/- 11 msec) compared with those in patients in Group IIa (143 +/- 40 msec, p less than 0.05) and Group IIb (310 +/- 71 msec, p less than 0.001). In conclusion, a diastolic pulmonary forward flow seems to be produced by the rapid equalization of right ventricular and pulmonary artery pressures due to severe pulmonary regurgitation in the face of decreased right ventricular compliance.     

海风藤中有PAF拮抗活性的苯骈呋喃类新木脂素

自福建产中药海风藤(Piper kadsura (Choisy)Ohwi)的藤茎中又分得5个苯骈呋喃类新木脂素,经光谱分析(UV,IR,MS,NMR,CD)和衍生物制备,确定化合物Ⅱ和Ⅴ为新结构。Ⅱ为化合物denudatin B的对映体,命名为(-)-denudatin B,V为7S,8S-3,4,3′-三甲氧基-7′-氧-缺8′,9′-7.O.4,′8.5′-新木脂素,命名为风藤素M(kadsurenin M)。化合物Ⅰ,Ⅲ和Ⅳ分别为已知化合物海风藤酮(Ⅰ),(-)-acuminatin(Ⅲ)和(+)-licarin A(Ⅳ)。PAF受体结合实验证明,(-)-denudatin B也具有较强的PAF拮抗活性。     

At least three hepatitis C virus strains implicated in Swedish and Danish patients with intravenous immunoglobulin-associated hepatitis C

BACKGROUND: Three reported Swedish cases of hepatitis C in patients receiving an intravenous immunoglobulin (Gammagard, Baxter Healthcare, Deerfield, IL) were among the first to bring to light a worldwide outbreak of hepatitis C associated with non-solvent/detergent (SD)- treated Gammagard. In February 1994, all implicated batches of Gammagard were recalled and exposed patients traced. STUDY DESIGN AND METHODS: Sera from all identified and hepatitis C-viremic Swedish and Danish patients (n = 14) exposed to the implicated batches underwent hepatitis C virus genotyping and sequencing of the core region and hypervariable region 1 of E2. Genomic amplification was also done on 15 non-SD-treated batches of Gammagard. RESULTS: Twelve patients were infected with subtype 1a and surprisingly, two with subtype 2b. Analysis of the core region showed identical sequences in four patients and the only consistently positive batch. Five patients shared another sequence, whereas three other subtype 1a patients each manifested unique sequences. The two subtype 2b isolates were identical. Genomic fingerprinting of the hypervariable region confirmed identity within each group with great stringency. Amplification with isolate-specific primers showed mixed infection in one patient whose exposure was confined to a single batch. CONCLUSION: The few batches implicated presumably were contaminated with several strains.     

氯胺酮和硝苯吡啶对培养神经元谷氨酸兴奋毒性的保护作用

以体外培养的大鼠胚胎皮层神经元为对象,以培养上清液中乳酸脱氢酶活性为指标,研究了谷氨酸兴奋毒性及药物的保护作用。结果表明,培养10d的皮层神经元置于含10或50μmol·L^-1谷氨酸和低糖(1g·L^-1)的DMEM培养液中后,随着作用时间的延长,LDH漏出逐渐增加。在谷氨酸处理前,于培养液中加入氯胺酮或硝苯吡啶,则LDH漏出量明显低于对照组。氯胺酮和硝苯吡啶并用,LDH漏出量比单独使用氯胺酮或硝苯吡啶下降更加明显。结果表明,谷氨酸对培养的神经元可产生严重损伤。氯胺酮和硝苯吡啶单用或并用均有明显的保护作用。     

咪苯嗪酮对TXA2和HHT生成的选择性抑制作用

咪苯嗪酮(CI-914)能抑制大鼠血小板环氧酶和TXA₂合成酶产物HHT的生成,而对脂氧酶产物12-HETE的生成仅高浓度药物才有弱的抑制作用,提示CI-914主要影响花生四烯酸(AA)环氧酶途径,而对脂氧酶途径影响较少。在大鼠血小板和中性白细胞CI-914能抑制TXA₂的生成,同时CI-914还可使白细胞6-keto-PGF_1a和血小板PGE₂的产生量显著增加,提示CI-914在这两种细胞引起了AA的转向合成。上述结果基本证实,CI-914在大鼠中性白细胞和血小板对TXA₂合成酶具有选择性抑制作用。     

脑益嗪对实验性脑血栓形成及血小板聚集的抑制作用

本文报道脑益嗪对大鼠实验性脑血栓形成及兔血小板聚集的抑制作用。经大鼠颈动脉顺行注射复合血栓诱导剂造成脑血栓模型,测定伊文思兰通过血脑屏障渗入脑实质的量以反映脑血栓的严重程度。结果表明脑益嗪(67 mg/kg,灌胃)有抗脑血栓形成的作用。半体内实验表明脑益嗪(34 mg/kg,灌胃)可抑制兔血小板聚集。     

Post-traumatic big toe reconstruction using free flaps

The big toe is of great importance for good stability and gait, but few reports have documented reconstruction of big toe defects. In this study, seven male patients, aged 17 to 59 years at surgery (average: 35 years), were treated for big toe defects. The metatarsophalangeal (MTP) joints of the big toe were intact in all patients. Five patients were treated with free peroneal flaps (including one perforator flap), and two with free scapular flaps; flap sizes ranged from 9 x 4 to 24 x 6 cm. Follow-up periods ranged from 10 to 29 months, (average: 16.6 months). The iliac was used as the grafted bone in four patients and the scapula in one. Six flaps survived completely, and bone unions were achieved within 3 months. One flap became partially necrotic due to arterial thrombosis. All patients returned to their original jobs, and the cosmetic appearances of all toes were acceptable.