重组集落刺激因子对大鼠正常骨髓及其白血病细胞体外增殖的影响

通过体外半固体培养集落形成和液体培养测定分析了重组的人或小鼠集落刺激因子对大鼠正常骨髓及其白血病细胞生长的影响。实验结果表明，重组的人巨噬细胞集落刺激因子（ｒｈＭ－ＣｓＦ），粒细胞集落刺激因子（ｒｈＧ－ＣＳＦ）和重组的小鼠粒－巨噬细胞集落刺激因子（ｒｍＧＭ－ＣＳＦ）能明显促进褐家（ｂｒｏｗｎＮｏｅｗａｙ）大鼠正常骨髓造血祖细胞的生长，在终浓度１０００ｋＵ·Ｌ－１时，它们的刺激指数分别为２８±ｓ１０，１２±ｓ４，２５±ｓ９。然而，ｒｈＧ－ＣＳＦ和ｒｍＧＭ－ＣＳＦ明显地抑制其白血病细胞集落形成，其ＩＣ５０分别为３５±ｓ８和１３４３±ｓ６３４ｋＵ·Ｌ－１也具有一定的抑制效应。同样，在液体培养中证实ｒｈＧ－ＣＳＦ和ｒｍＧＭ－ＣＳＦ明显地抑制ＬＴ１２白血病细胞ＤＮＡ合成及饱和生长密度（ＩＣ５０分别为１９１３和１８７ｋＵ·Ｌ－１）。重组的人粒－巨噬细胞集落刺激因子和小鼠多系集落刺激因子无论在半固体或液体培养中对大鼠正常骨髓造血祖细胞和白血病细胞的增殖均无明显影响。此外，还观察到大鼠急性白血病ＬＴ１２细胞经ｒｍＧＭ－ＣＳＰ（１０００ｋＵ·Ｌ－１）处理８ｄ后，６±ｓ１％的细胞显示具有还原硝基篮四氮唑的能力。     

Unusual causes of increased vascular impedance in renal transplants: duplex Doppler evaluation

Duplex Doppler ultrasound (US) examination of the renal vasculature has proved valuable in assessing the kidney transplant. The normal renal allograft exhibits low-impedance arterial inflow similar to that seen in the normotopic kidney. The authors and others previously reported that a high vascular impedance, defined as either a pulsatility index (PI) greater than 1.8 or a resistive index greater than 0.9, indicates acute vascular rejection (AVR). Although AVR remains the most common cause of increased PI, the authors noted ten episodes among 180 serially followed-up transplants in which abnormal waveforms were clearly not due to rejection. Four other causes of increased vascular impedance are reported, including renal vein obstruction, severe acute tubular necrosis, pyelonephritis, and extrarenal compression of the graft. These new causes only slightly decrease the specificity of high vascular impedance for rejection. Furthermore, the cause can usually be recognized from the clinical history or other US findings.     

Radiographic appearance of the sternomanubrial joint in arthritis and related conditions

The sternomanubrial joint (SMJ) was evaluated on the lateral chest radiograph in 177 patients with rheumatic disease and 69 non-rheumatic controls. Abnormalities were categorized as inflammatory changes, proliferative changes, or bone fusion. Patients with rheumatoid arthritis, psoriatic arthritis, or gout were found to have an increased incidence of inflammatory changes. Rheumatoid variants predisposed to early fusion of the SMJ. Patients with diffuse idiopathic skeletal hyperostosis (DISH) exhibited massive and unique hyperostotic changes.     

Pulse oximetry in ventilated preterm newborns: reliability of detection of hyperoxaemia and hypoxaemia, and feasibility of alarm settings

The aim of our study was to evaluate the reliability of pulse oximetry in detecting both hyper- and hypoxaemic states and to create clinically feasible alarm limits. A total of 792 readings of a pulse oximeter and corresponding values of arterial oxygen tension from 146 (79M, 67F) artificially ventilated preterm newborns with indwelling umbilical artery catheters were compared. Predictive value analysis of pulse oximeter readings related to arterial oxygen tension confirmed the ability of the pulse oximeter to identify both hypoxaemia and hyperoxaemia. However, a clinically feasible and safe range of alarm limits for maintenance of arterial oxygen tension of 40-90 mmHg (5.3-12kPa) could only be established at a sensitivity level less than 0.9. At a level of 0.85, the alarm range on the pulse oximeter was 92.5-95%. Based on these findings, we are concerned about using pulse oximetry as the sole means of oxygen monitoring for preterm infants receiving supplementary oxygen. A combination of the pulse oximetry with other methods of blood-gas monitoring seems mandatory     

利巴韦林在体外对小鼠脾细胞NK活性的影响

采用¹²⁵I-UdR同位素释放试验,观察利巴韦林(三氮唑核苷,RTC)在体外对小鼠脾细胞自然杀伤(Nk)活性的影响。结果表明,RTC的剂量与NK活性呈负相关,在5umol·L^-1时RTC即可显著抑制NK活性。RTC与地塞米松合用对NK活性的抑制有相加作用,而RTC与γ干扰素合用则互为拮抗作用。此外,还发现RTC能明显降低刀豆蛋白A诱生的小鼠脾细胞干扰素及白细胞介素-2的产量,推测RTC对NK活性抑制的部分机理是阻碍了这些淋巴因子的生成。