Quantitative evaluation of hand cranking a roller pump in a crisis management drill

The heart-lung machines for open-heart surgery have improved over the past 50 years; they rarely break down and are almost always equipped with backup batteries. The hand-cranking procedure only becomes necessary when a pump breaks down during perfusion or after the batteries have run out. In this study, the performance of hand cranking a roller pump was quantitatively assessed by an objective method using the ECCSIM-Lite educational simulator system. A roller pump connected to an extracorporeal circuit with an oxygenator and with gravity venous drainage was used. A flow sensor unit consisting of electromagnetic sensors was used to measure arterial and venous flow rates, and a built-in pressure sensor was used to measure the water level in the reservoir. A preliminary study of continuous cranking by a team of six people was conducted as a surprise drill. This system was then used at a perfusion seminar. At the seminar, 1-min hand-cranking drills were conducted by volunteers according to a prepared scenario. The data were calculated on site and trend graphs of individual performances were given to the participants as a handout. Preliminary studies showed that each person's performance was different. Results from 1-min drills showed that good performance was not related to the number of clinical cases experienced, years of practice, or experience in hand cranking. Hand cranking to maintain the target flow rate could be achieved without practice; however, manipulating the venous return clamp requires practice. While the necessity of performing hand cranking during perfusion due to pump failure is rare, we believe that it is beneficial for perfusionists and patients to include hand-cranking practice in periodic extracorporeal circulation crisis management drills because a drill allows perfusionists to mentally rehearse the procedures should such a crisis occur.     

Skin vascular response in the hand during sinusoidal exercise in physically trained subjects

The effect of physical training on the cutaneous vascular response during transient exercise load is unclear. We determined the phase response and amplitude response of cutaneous vascular conductance (CVC) in the hand during sinusoidal exercise in endurance exercise-trained and untrained subjects. Subjects exercised on a cycle ergometer with a sinusoidal load for 32 min. The load variation ranged from 10% [23 (1) W in the trained group, 19 (1) W in the untrained group] to 60% [137 (4) W, 114 (6) W] of peak O₂ uptake, and five different time periods (1, 2, 4, 8, and 16 min) were selected. Skin blood flow in the dorsal hand and palm were monitored by laser-Doppler flowmetry. CVC was evaluated from the ratio of blood flow to mean arterial pressure. During sinusoidal exercise, the amplitude of CVC was smaller in the dorsal hand than palm for shorter periods (1, 2, and 4 min) (P<0.05). The phase lag of CVC was smaller in the dorsal hand than palm for longer periods (8 and 16 min) (P<0.05). The amplitude response did not differ significantly between the two groups. The phase lag of CVC in the dorsal hand (P<0.05) and palm (P=0.06) was larger in the trained group than untrained group. These findings suggest that glabrous and nonglabrous skin vascular responses in the hand differ during transient exercise load, and physically trained subjects show a slower vascular response in the two skin areas to exercise stimulation than do untrained subjects.     

Effects of fibrinogen on lipid peroxidation in patients with coronary heart disease and in vitro

In patients with coronary heart disease oxidizability of lipids during Cu²⁺-induced oxidation of blood plasma inversely correlated with fibrinogen content. A positive correlation was found between the amount of lipid peroxidation products in the plasma from these patients and fibrinogen content. The increase in fibrinogen content was associated with high levels of total lipids and triglycerides and low concentration of high-density lipoprotein cholesterol. In vitro experiments demonstrated that fibrinogen reduces oxidizability of blood plasma. Our results suggest that the decrease in lipid oxidizability at high concentration of fibrinogen in patients with coronary heart disease is related to predominant oxidation of fibrinogen and its competition with plasma lipids during Cu²⁺-induced oxidation.     

基于暗视场荧光图像分析的大鼠微血管流速测量系统的建立

将荧光标记的自身红细胞注入SD大鼠体内,在荧光显微镜下观测标记红细胞在大鼠微血管中的流动情况,并通过显微摄像系统将整个过程以视频信号的形式存贮。使用视频采集卡将流速变化过程回放采样,得到暗视场下的荧光图像。然后利用帧图像分离出奇偶场的图像分析方法测定血流速度。在该系统下测量流动小室中荧光小球的流速,得到的测量值与实际值之间的误差小于7%,两者没明显的差异(P>0.05),流速测量的上限为9.6mm/s。并在大鼠微循环障碍研究中,应用此系统得到了血流速度随时间变化的情况。     

米非司酮终止中期妊娠时胎盘循环与超微结构的变化

观察３０例妊娠１６～２４周需终止妊娠者服用米非司酮前后子宫动脉和脐动脉血流速度波型的变化，并用电镜观察了５例胎盘微血管的改变。结果：服用米非司酮后，子宫动脉阻力指数（ＲＩ）和Ｓ／Ｄ比值及脐动脉的Ｓ／Ｄ比值较用药前明显增高，胎盘微血管壁有损伤性表现。提示：子宫胎盘循环动力学的变化及胎盘微血管的损伤可能是米非司酮终止妊娠的重要环节。     

Combined use of positive and negative immunomagnetic isolation followed by real-time RT-PCR for detection of the circulating tumor cells in patients with colorectal cancers

To establish a novel molecular diagnostic method of detecting circulating tumor cells (CTCs) LS174T colon cancer cells were serially diluted with normal blood. Additional peripheral blood samples were collected from 25 patients with colorectal carcinoma. Mononuclear cells (MNCs) were collected, equally divided into four parts, and then cancer cells were enriched by four methods: method A, nonimmunobead method; method B, negative immunobead method: CD45 immunomagnetic beads were used to deplete the leukocytes; method C, positive immunobead method: Ber-EP4 immunomagnetic beads were used to enrich cancer cells; method D, negative-and-positive immunobead method: CD45 immunomagnetic beads were first used to deplete the leukocytes from MNC and then Ber-EP4 immunomagnetic beads were used to enrich cancer cells. Finally, real-time quantitative RT-PCR was used to monitor mRNA expression of ₂-mircoglobulin (2M) and carcinoembryonic antigen (CEA). The relative CEA mRNA values were corrected with reference to 2M mRNA, to CEA mRNA/2M mRNA ratios according to a CEA mRNA external standards prepared with tenfold serial dilutions (1–10⁴ IS174T cells) of cDNA and 2M mRNA external standards prepared with tenfold serial dilutions (10²–10⁷ leukocytes) of cDNA. In recovery experiments a significant correlation between the number of cancer cells and CEA mRNA expression was found when CD45 or Ber-EP4 immunomagnetic beads were used alone. A highly significant correlation was found when CD45 and Ber-EP4 immunomagnetic beads were used successively. The sensitivity of method D was one cancer cell per milliliter of blood. Circulating cancer cells were detected in 19 of 25 patients with colorectal cancers. The relative CEA mRNA value obtained by method D was the smallest. The positive detection rate of circulating cancer cells in patients at Dukes B, C, and D stages were 25.0% (1/4), 83.3% (10/12), and 88.9% (8/9). Combinative use of immunomagnetic isolation followed by real-time RT-PCR is a useful technique to detect circulating tumor cells in patients with colorectal carcinomas. Applying negative and positive immunomagnetic beads successively yields the highest correlation with amount of tumor cells.     

Effects of muscle blood flow on muscle energy metabolism and contractility

Energy metabolism and contractility of rat’s femoral triceps muscles were investigated by varying blood flow levels with ligation of the femoral artery. The triceps were stimulated electrically to produce equivalent conditions as exercise loading, and phosphorus nuclear magnetic resonance (³¹P-NMR) spectra and muscle tension levels were monitored. The ratio of inorganic phosphate (Pi) to ‘Pi+phosphocreatine (PCr)’, i.e. Pi/(Pi+PCr), was obtained from ³¹P-NMR spectra. This ratio was related to the reduction of blood flow ratio (BFR) during and after the stimulation period, whereas before starting the stimulation, there was no significant correlation. These findings indicate: (i) muscle energy metabolism during decreased blood flow is influenced by the stimulation (loading) given to the muscle; and (ii) changes of muscle energy metabolism due to decreased muscle blood flow during the loading is evaluable by measuring ³¹P-NMR spectra. Muscle tension reached the plateau 8 min after starting the stimulation, regardless of BFR, but muscle tension ratio decreased as BFR became lower. This indicates that decreased blood flow diminishes muscle contractility, and then lowers muscle function levels. Our findings indicate that muscle blood flow plays an important role in muscle function, and blood flow and muscle function levels are evaluable by measuring ³¹P-NMR spectra of the muscle.     

p53蛋白的免疫亲和层析纯化

建立了ｐ５３单克隆抗体ｐＡｂ１８０１的免疫亲和层极法纯化ｐ５３蛋白，所纯化的ｐ５３蛋白经Ｗｅｓｔｅｒｎ Ｂｌｏｔ（ＥＣＬ法）检测证明：用此法从ｐ５３阳性的ＳＷ４８０细胞中分离到ｐ５３蛋白。银染显示ｐＨ２．０甘氨酸缓冲液比ｐＨ２．８的甘氨酸缓冲液洗脱效果好，这种方法的建立将为分离肿瘤细胞中引起ｐ５３蛋白功能失活和研究肿瘤发生机制提供一种有效途径。     

The dorsal facial area of the medulla in cats: inhibitory action of serotonin on glutamate release in regulating common carotid blood flow

Whether glutamate and serotonin would release and interact in the dorsal facial area (DFA) of cat medulla to regulate common carotid arterial (CCA) blood flow was explored by placing a microdialysis probe in DFA and employing high performance liquid chromatographic technique. Glutamate concentration was dose-dependently decreased by perfusion with serotonin, or alaproclate, a serotonin reuptake inhibitor. Serotonin and glutamate concentrations were increased by perfusion with KC1, a depolarizing agent. Furthermore, CCA blood flow was decreased when glutamate concentration was reduced by serotonin or alaproclate perfusion, and conversely increased when glutamate concentration was increased by KC1 perfusion. In conclusion, glutamate and serotonin releases in DFA that involve regulation of CCA blood flow are tonically mediated by nerve terminals. The glutamate release is depressed by the serotonin release.     

Variations of the origin of the artery of the sinoatrial node in normal human hearts

Summary The artery of the sino-atrial node was studied in 100 normal human hearts after injection of each coronary artery with coloured gelatine containing a radiopaque substance. The hearts belonged to 69 males and 31 females, being 64 Caucasians and 36 non-Caucasians (Negroes and Mulattoes) whose age ranged from 7 to 80 years. Since the individuals had committed suicide or were victims of accidents, their hearts, after pathologists' evaluation, were considered normal. The sinoatrial node of the normal human heart is supplied by the right coronary artery more frequently (58%±4.9% of the cases) than by the left (42%±4.9). The right anterior medial atrial artery, originating from the right coronary at the level of the medial third of the right anterior quadrant of the atrial dome, is most frequently (50%±5) responsible for the blood supply of the sinoatrial node. Among the branches of the left coronary artery, the left anterior medial atrial artery, originating at the level of the medial third of the left. anterior quadrant of the atrial cupola, was the most frequent blood supplier (25%±4.3) of the sinoatrial node. The origin of the artery of the sinoatrial node from the proximal portion or trunk of the left coronary artery was less frequent (12%±3.2) than the origin from the circumflex artery (30%±4.5). Neither sex nor race influenced the variations of the origin of the sino-atrial node.

---

Variations d'origine de l'artère du noeud sinu-atrial du coeur humain normal

Résumé L'a. du noeud sinu-atrial a été étudiée sur 100 coeurs humains normaux après injection de chaque a. coronaire à la gélatine colorée additionnée d'une substance radio-opaque. Les coeurs provenaient de 69 hommes et 31 femmes, 64 caucasiens et 36 non caucasiens (nègres et mulâtres) âgés de 7 à 80 ans. Ces sujets étant décédés par suicide ou des suites d'accidents, leurs coeurs ont été considérés comme normaux après examen anatomo-pathologique. Le noeud sinu-atrial du coeur humain est vascularisé par l'a. coronaire droite plus fréquemment (58 %±4,9) que par l'a. coronaire gauche (42 %±4). L'a. atriale antéro-médiale droite, issue de l'a. coronaire droite au niveau du tiers médial du quadrant antérieur droit du dôme atrial est l'artère la plus fréquemment en cause (50 %±5) dans la vascularisation du noeud sinuatrial. Parmi les branches de l'a. coronaire gauche, l'a. atriale antéro-médiale gauche, née au niveau du tiers médial du quadrant antérieur gauche du dôme atrial, était la branche la plus fréquemment en cause (25 %±4,3) dans la vascularisation du noeud sinu-atrial. La naissance de l'a. du noeud sinu-atrial à partir de la partie proximale ou du tronc de l'a. coronaire gauche était moins fréquente (12 %±3,2) que son origine à partir du rameau circonflexe (30 %±4,5). Les variations d'origine de l'a. du noeud sinu-atrial n'apparaissaient pas influencées par le sexe ou la race.