温度对脐血清集落刺激活性水平的影响

脐带血作为造血干、祖细胞的来源之一,已日益受到人们的关注。本实验供助粒、巨噬祖细胞微量培养技术观察了不同温度、不同时间对脐血清ＣＳＡ水平的影响。结果显示,室温与４℃保存条件下,第１、３、７天之间ＣＳＡ水平无显著性差异（Ｐ〉０．０５）;第７天后开始下降,第１４天明显下降（Ｐ〈０．０１）;第２８一在活性基本消失。－２０℃保存条件下第１、３、７、１４、２８天之间均无显著性差异（Ｐ〉０．０５）。这一结果对     

MN9202保护血栓大鼠尾动脉血管作用

观察新二氢吡啶类钙拮抗剂２,６－二甲基－４－（３－硝基苯基）－１,４－二氢－３,５－吡啶二羧酸－３－甲酯－５－正戊酯（ＭＮ９２０２）对血栓形成大鼠尾动脉血管平滑肌及内皮功能的影响。方法大鼠脚趾ｓｃ注射角叉来胶制备血栓模型,并于注射角叉菜胶前２４ｈ,１ｈ及注射后２４ｈｉｐＭＮ９２０２１μＭＯＬ．ＫＧ＾－１,取尾动脉血栓波及不同区域的三段血管,以去甲肾上腺素（ＮＥ）,乙酰胆碱（ＡＣｈ）,亚硝酸钠（Ｎａ     

Action of ryanodine on neurogenic responses in rat isolated mesenteric small arteries

1. Rat mesenteric arteries (∼250 μm) were set up in a single-channel isometric myograph designed to allow fluorescence measurements concurrent with field stimulation of intramural nerves. Vessels were loaded with 6 μM fura-2AM for 2 h and simultaneous recordings of neurogenic contraction (force) and intracellular calcium [Ca²⁺]_i were obtained. In other experiments, arteries were loaded with 1 μCi ml⁻¹ [³H]-noradrenaline (NA) for 30 min in order to measure release of [³H]-NA in response to field stimulation to examine whether ryanodine directly inhibited neuronal release of NA.
2. Arteries were activated by single intermittent field stimulation or continuously to excite intrinsic sympathetic nerves, or by cumulative addition of noradrenaline (1 nM–10 μM) to the bathing solution.
3. Pre-incubation with ryanodine markedly inhibited the contraction and [Ca²⁺]_i release in response to single-pulse nerve stimulation. Ryanodine also inhibited an early phasic component of the response to continuous field stimulation and reduced the rate of rise in force in response to continuous field stimulation. However, stable maximal contraction and [Ca²⁺]_i in response to continuous field stimulation as well as maximal responses to exogenous NA were unaffected. Release of [³H]-NA in response to single intermittent field stimulation was not affected by ryanodine when compared to vehicle.
4. Our results suggest that brief intermittent activation of intramural sympathetic nerves increases [Ca²⁺]_i and contracts small arteries primarily by releasing Ca²⁺ from a ryanodine-sensitive intracellular store. In contrast, the stable rise in tone and [Ca²⁺]_i resulting from continuous nerve stimulation may largely depend on sources of Ca²⁺ other than the ryanodine-sensitive intracellular store.

     

Influence of ETR-p1/f1 antisense peptide on endothelin-induced constriction in rat renal arcuate arteries

1. This study set out to examine the endothelin receptor subtypes mediating vasoconstriction in the rat renal arcuate artery. This was done in isolated vessels 120–200 μm in diameter, incubated with a selective agonist and the novel ‘antisense'' peptide to part of the human endothelin_A receptor.
2. Groups of vessels (n=6) were incubated with increasing concentrations of endothelin-1 (ET-1), from 1 to 100 nM, which caused a 65% maximal contraction at the highest dose with an pEC₅₀ of 8.16±0.11 M. By contrast, in six other vessels sarafotoxin 6c over the same dose range gave a minimal contraction (around 5% of maximum).
3. Preincubation of six vessels with the antisense peptide ETR p₁/f1 at 1 μM had no effect on the ET-1 induced vasoconstriction, in terms of displacement of the concentration-response curve or the maximal tension achieved by the agonist. In the six vessels exposed to 4 μM ETR p₁/f1, there was a significant shift of the concentration-response curve and a lower pEC₅₀ at 7.78±0.09 M (P<0.05). At the highest concentrations of ETR p₁/f1, there was a marked suppression of all responses to ET-1, which at the maximal concentrations tested, 0.1 μM, only reached some 10% of the maximal achievable contraction.
4. Increasing ET-1 concentrations up to 2 μM in vessels incubated with 40 μM ETR-p₁/f1 showed that the blockade could be overcome and that the relationship was shifted to the right (P<0.001) by approximately one log unit with a pEC₅₀ of 7.13±0.11 M. A Schild plot of the data indicated the antagonist to be acting competitively at a single population of receptors.
5. At the highest concentrations tested, 40 μM, ETR-p₁/f1 had no effect on noradrenaline-induced contractions, indicating a lack of non-specific actions.
6. Together, these data suggest that at the rat renal arcuate artery the endothelin_A receptor is the predominant functional receptor mediating contraction. Furthermore, this study has shown the potential usefulness of this novel type of ‘antisense'' peptide in blocking receptor activation.

     

The basal and stimulated release of the endothelium-derived relaxing factor from isolated pig coronary arteries does not interfere with the vascular release of superoxide

Oxygen-derived free radicals, in particular superoxide anions, are known to inactivate the endogenous vasodilator endothelium-derived relaxing factor (EDRF) which is probably identical with the gaseous radical nitric oxide. It is possible that EDRF is not the target of superoxide anions but may also be an endogenous scavenger of this radical.Superoxide anions generated by the vessel wall were measured by a modified lucigenin-enhanced chemiluminescence technique in isolated pig coronary artery rings with intact endothelium.The addition of bovine superoxide dismutase, a scavenger of superoxide anions, decreased the chemiluminescence signal by 40 ± 26% (mean ± SD; P < 0.05; n = 21) indicating reduced generation/release of superoxide anions. In contrast, pretreatment of coronary artery rings with diethyldithiocarbamate, an inhibitor of the intrinsic copper-zinc superoxide dismutase, increased the chemiluminescence response by 136 ± 128°10 (P < 0.05; n = 21). This increase in the chemiluminescence response induced by diethyldithiocarbamate-pretreatment was almost abolished in the presence of added bovine superoxide dismutase. Specific inhibition of the EDRF release with nitro-l-arginine (100 M) did not affect the chemiluminescence response. On the other hand, stimulation of the EDRF release by substance P (10 nM) or addition of the endothelium-mediated relaxant bradykinin (0.1 M) did not affect the chemiluminescence response. Stimulation of the EDRF release with serotonin (0.1 M) significantly reduced the photon emission by 15 ± 16% (n = 27). However, this effect of serotonin on the chemiluminescence response could not be prevented by specific inhibition of the EDRF release with nitro-l-arginine (100 M) but could be prevented by buffering the acidic serotonin solution with NaOH to pH 7.4.Our results suggest that basal and agonist-stimulated release of EDRF in isolated pig coronary artery rings does not interfere with the basal generation/release of superoxide anions derived from the vascular wall. Correspondence to: A. Mugge at the above address     

Syndrome X in women is associated with oestrogen deficiency

This study was undertaken to ascertain whether gynaecologicalhistory or a reduction in ovarian hormones are triggers of anginain menopausal women with a positive exercise test and normalcoronary arteries. The majority of patients with angina pectoris,a positive exercise test and normal coronary arteries are female,suggesting that the female gender may be important in the aetiology.We studied the gynaecological features of 107 women (age 53±9 years) with syndrome X, taken from a population of134 patients including 27 males. Cardiological investigationswere undertaken and detailed gynaecological history obtainedfrom all the female patients. Menopausal status was confirmedby plasma levels of oestradiol-17ß100 pmol. l^–1. In 95 of the 107 female patients, chest pain began either duringthe perimenopausal period (32) or after the menopause (63).Of the 63 menopausal patients, 43 had undergone hysterectomyat an average of 8 ± 6 years prior to the onset of chestpain. The incidence of hysterectomy in the study population(40%) was four times greater than that of an age-matched population.These findings confirm that the majority of patients with syndromeX are women in whom the chest pain began after the onset ofmenopause. Ovarian hormone deficiency may, therefore, play arole in the onset of syndrome X in female patients.     

Intramural hydatid cysts of pulmonary arteries: CT and MR findings

Involvement of the pulmonary artery by echinococcosis usually occurs due to pulmonary embolization after rupture of the cyst in the right ventricle or, rarely, by dissemenation from a hepatic focus. This paper presents an adult patient with intramural hydatid cysts of the pulmonary arteries, which apparently grew slowly toward the lumina resulting in complete luminal occlusion, enabling sufficient time for development of sufficient perfusion from the bronchial arteries. The condition apparently resulted from embryos of the parasite, which entered the vasa vasorum of the pulmonary arteries, a previously unreported mechanism.     

Povidone-iodine in umbilical cord care interferes with neonatal screening for hypothyroidism

Out of 1346 newborns screened for congenital hypothyroidism, 31 non-hypothyroid infants were summoned because of a thyroid stimulating hormone (TSH) level above 10 U/ml. False-positive TSH levels were significantly more frequent in the babies treated with povidone-iodine (4.6%) than in those treated with either alcohol or triple dye (0.7%).Conclusion Iodine containing solutions should be avoided in umbilical cord care of the newborn     

原代培养人脐动脉内皮细胞的超微结构

对不用贴附基质和生长因子情况下原代培养７２ｈ的人脐动脉内皮细胞（ＨＵＡＥＣ）进行了透射电镜观察。电镜下ＨＵＡＥＣ形态不规则,细胞器丰富。核周有散在的滑面内质网、粗面内质网及较多的线粒体,后者有些为板层状嵴,另一些为管泡状嵴。细胞膜下可见微管,胞质内有大量循同一方向排列的微丝。Ｗｅｉｂｅｌ Ｐａｌａｄｅ小体内含涡旋状排列的细管。胞质内含丰富的糖原颗粒。细胞核内常染色质较多,异染色质主要分布于核膜下。有时可见处于无丝分裂状态的细胞,核已分裂为二,但二者间仍有核膜相连。内皮细胞间以紧密连接或中间连接的方式相连。以上结果表明：人脐动脉内皮细胞在体外培养条件下代谢功能旺盛,且具有参与脂类代谢的细胞器,细胞以无丝分裂方式增殖。     

监测胎儿脑,脐血流阻力指标预测胎儿宫内缺氧

目的：预测胎儿宫内缺氧。方法：应用彩色多普勒超声对１４７例孕妇进行详细观察。结果：胎儿的大脑中动脉（ＭＣＡ）血流Ｓ／Ｄ值〈４、ＰＩ〈１．４、ＲＩ值〈０．６（Ｓ／Ｄ、ＰＩ、ＲＩ值简称阻力指标）;脐动脉（ＵＭＡ）血流Ｓ／Ｄ值〉３、ＰＩ值〉１．７、ＲＩ值〉０．８;ＰＩ、ＲＩＭＣＡ／ＰＩ、ＲＩＵＭＡ〈１时,提示胎儿宫内缺氧。妊高征组和伴ＩＵＧＲ的妊高征组缺氧发生率与正常组缺氧发生率比较差异有显著性（Ｐ〈０