Early changes in alveolar fluid clearance by nitric oxide after endotoxin instillation in rats

Alveolar fluid clearance may be inhibited and/or stimulated under pathologic conditions. We examined the early change of alveolar fluid clearance after endotoxin instillation in adult rats. We employed electron paramagnetic resonance nitric oxide (NO) trapping technique with iron complex with N,N-diethyldithiocarbamate as an NO trapping agent. We found that lung NO signals reached the highest magnitude by 6 hours after endotoxin instillation. NO production was accompanied by increases in lung cyclic guanosine monophosphate levels. Alveolar fluid clearance decreased significantly 6 hours after the administration of the endotoxin and increased further at 24 hours. These changes were shown to be related to the function of amiloride-sensitive sodium ion channels. Treatment with gadolinium chloride and aminoguanidine significantly decreased lung NO and cyclic guanosine monophosphate levels and completely ameliorated the decrease in alveolar fluid clearance. In addition, the increase in alveolar fluid clearance at 24 hours returned to normal levels after treatment with gadolinium chloride and aminoguanidine. We found immunoreactive inducible nitric oxide synthase to be abundantly expressed in the cytoplasm of alveolar macrophages. Our results suggest that alveolar endotoxin inhibits alveolar fluid clearance at 6 hours by NO. NO is produced via inducible NO synthase in endotoxin-stimulated alveolar macrophages and was also shown to increase alveolar fluid clearance at 24 hours.     

弓形虫感染大鼠外周血T细胞亚群动态变化

目的观察弓形虫感染大鼠外周血T淋巴细胞亚群的动态变化。方法将58只清洁级SD成年大鼠随机分成9组,其中8组为实验组,1组为对照组,实验组每鼠腹腔注射2×105/LCF-11纤维素纯化的活弓形虫速殖子悬液2ml,对照组腹腔注射2ml生理盐水,并留4只为正常对照鼠。分别于弓形虫感染后1、3、7、14、28、35、42、60d时取大鼠外周全血,用流式细胞术检测外周血T细胞亚群CD3+、CD4+、CD8+百分比。结果弓形虫感染后3d、7d时,CD3+水平降至最低,但与正常鼠和对照鼠无显著性差异(P>0.05),至感染14d基本恢复至正常水平,此后再无明显变化。CD8+亚群水平在感染后3d、7d、14d时均显著低于正常水平(P<0.05),至感染后28d恢复正常水平。而CD4+亚群水平在整个感染过程中无明显变化(P>0.05)。CD4+/CD8+比例在感染后3d、7d、14d时显著高于正常鼠和对照鼠(P<0.05)。结论弓形虫感染影响大鼠外周血T淋巴细胞亚群比例,但可自行恢复正常。     

Portal and peripheral blood short chain fatty acid concentrations after caecal lactulose instillation at surgery.

The major end products of fermentation, short chain fatty acids (acetate, propionate, butyrate) were measured in portal and peripheral venous blood after the caecal instillation of lactulose at surgery in patients undergoing elective cholecystectomy. Blood samples for short chain fatty acid measurement were taken before and at 15 minute intervals up to 60 minutes after caecal instillation of either 20 ml sterile saline or 6.7 g or 10 g lactulose. Fasting concentrations (n = 28) were (mumol/l, mean (SD)); portal acetate 128.0 (70.8), propionate 34.4 (23.3), butyrate 17.6 (18.4); peripheral acetate 67.0 (23.0), propionate 3.7 (1.2), butyrate traces only. After lactulose there was a rapid rise in portal short chain fatty acids with peak concentrations being reached in 15 to 45 minutes. Mean peak concentrations (mumol/l (SD)) after 10 g lactulose were acetate 240.9 (142.2), propionate 39.0 (17.8) and butyrate 26.9 (17.6). The changes in acetate concentrations seen in portal blood were reflected in peripheral blood acetate measurements. In contrast with portal blood, only small amounts of propionate and traces of butyrate were found in peripheral blood.     

外周血干细胞采集对外周血细胞成分的影响

目的 :探讨连续干细胞采集对外周血细胞成分的影响以及患者对连续采集的耐受性。方法 :在外周血干细胞采集过程中连续检测外周血细胞计数、CD3 4+ 细胞及其亚群 ,造血干细胞培养。结果 :采集后 6例患者出现贫血 ,2 1例原有贫血加重 ,血红蛋白由 (10 7.6± 11.7)g/L降至 (10 0 .3± 11.7)g/L (P <0 .0 1) ;9例出现血小板减少 ,17例原有血小板减少程度加重 ,血小板由采集前的 (96 .46± 5 5 .45 )× 10 9/L降至 (84.71± 14.97)× 10 9/L(P <0 .0 1)。贫血及血小板减少的程度与采集产品中红细胞及血小板的含量显著相关 (P <0 .0 1)。造血干细胞采集后血中的CD3 4+ /CD3 8-细胞以及CD3 4+ /HLA DR-细胞显著增加 ,而BFU E和CFU GM无明显变化。结论 :外周血干细胞采集可使外周血中多能干细胞水平增加 ,但连续采集可使贫血和血小板减少的危险性增加 ,但均可耐受。     

Cerebral blood flow and the development of ammonia-induced brain edema in rats after portacaval anastomosis.

Two mechanisms may account for brain edema in fulminant hepatic failure: the osmotic effects of brain glutamine, a product of ammonia detoxification, and a change of cerebral blood flow (CBF). We have shown brain edema, a marked increase in brain glutamine, and a selective rise in CBF in rats after portacaval anastomosis receiving an ammonia infusion. In this study, we inhibited the activity of glutamine synthetase with methionine-sulfoximine (MSO) and examined ammonia levels, brain water and CBF. Four groups received either a continuous ammonium acetate or control infusion; half of the animals had been pretreated with MSO or vehicle. The ammonia group exhibited brain edema (79.97 +/- 0.04 vs. 81.11 +/- 0. 13% water), an increase in cerebrospinal fluid (CSF) glutamine (1.29 +/- 0.21 vs. 2.84 +/- 0.39 mmol/L) and CBF (63 +/- 11 vs. 266 +/- 45 mL/min/100 g brain). When MSO was added to the ammonia infusion, ammonia levels rose further (928 +/- 51 vs. 1,293 +/- 145 mmol/L, P <.05) but CSF glutamine decreased (2.84 +/- 0.39 vs. 1.61 +/- 0.2 mmol/L, P <.01). Brain edema (80.48 +/- 0.11%) and cerebral hyperemia (140 +/- 25 mL/min/100 g brain) were significantly ameliorated in the ammonia plus MSO group. Brain output of circulating nitric oxide (NO(x)) was increased in the ammonia-infused group but normalized in the ammonia plus MSO group. In this model, the rise of CBF reflects intracranial events that occur after glutamine synthesis. Activation of nitric oxide synthase in the brain could account for these findings.     

Increase in the QRS duration after amelioration of peripheral edema and after hemodialysis

Association among weights, amplitude of QRS complexes, and QRS duration in patients with peripheral edema has been described. This study explored whether increase in QRS duration occurs with amelioration of peripheral edema or after hemodialysis. Sums of the amplitudes of the 12 electrocardiographic leads and corresponding QRS duration were measured in 12 patients with peripheral edema before and after loss of weight, in 28 patients with a critical illness but without change in their weight ("controls"), and in 1 patient before and after hemodialysis. QRS duration increased from 90.1+/-25.0 milliseconds to 101.7+/-25.8 milliseconds (P=.001) in patients with peripheral edema, was unchanged in the controls, and increased from 87.8+/-5.9 milliseconds before to 92.7+/-6.7 milliseconds after hemodialysis (P=.007). It is proposed that these increases in QRS duration are only apparent (not electrophysiologically real), representing an extracardiac phenomenon mediated by alterations in the composite impedance of the passive body volume conductor, resulting in measurement of augmented QRS complexes after fluid removal. The clinical implications for patients with congestive heart failure are discussed.     

Differential interaction of magnetic nanoparticles with tumor cells and peripheral blood cells

Purpose: The separation of tumor cells from healthy cells is a vital problem in oncology and hematology, especially from peripheral blood. Magnetic assisted cell sorting (MACS) is a possibility to fulfill these needs. Methods: Tumor cell lines and leukocytes from peripheral blood were incubated with carboxymethyl dextran-coated magnetic nanoparticles under various conditions and separated by MACS. Results: We studied the interaction of magnetic nanoparticles devoid of antibodies with healthy and tumor cells. The magnetic nanoparticles interact with tumor cells and leukocytes and are located predominantly within the cell cytoplasm. Incubation of cell culture cells with magnetic nanoparticles led to a labeling of these cells without reduced biological properties for at least 14 days. The interaction of the magnetic nanoparticles with cells depends on several factors. The ionic strength (osmolality) of the solvent plays an important role. We could show that an increase in osmolality led to a dramatic reduction of labeled leukocytes. Tumor cells, however, are mildly affected. This could be detected not only in pure cultures of tumor cells or leukocytes but also in mixed cell populations. Conclusion: This observation gives us the opportunity to selectively label and separate tumor cells but not leukocytes from the peripheral blood.     

Measurement of inhibin concentrations in men: study of changes after castration and comparison with androgen levels in testicular tissue, spermatic venous blood, and peripheral venous blood

We measured serum inhibin levels in eight untreated patients with prostatic cancer undergoing castration by RIA using an antiserum against 31-kDa bovine follicular fluid inhibin. The inhibin concentrations in testicular tissue and spermatic venous blood were also measured in six of these patients. Serum inhibin levels (mean +/- SD, 377.8 +/- 212.1 U/L), declined rapidly after castration (15 min after, 233 +/- 171.4; 30 min, 224.6 +/- 156.6; 1 h, 181.5 +/- 95.9; 2 h, 174.3 +/- 69.4; 4 h, 122 +/- 6.4; 6 h, less than 120). High concentrations of inhibin were detected in testicular tissue (31,360 +/- 15,180 U/kg), and the levels in spermatic venous blood (3,178.3 +/- 1,386.8 U/L) were approximately 10 times greater than those in peripheral blood (385.5 +/- 233.1 U/L). Testosterone levels were 1,968.2 +/- 992.3 nmol/kg in testicular tissue and approximately 100 times greater in spermatic venous blood (1,631.6 +/- 389.7 nmol/L) than in peripheral blood (18.0 +/- 4.4 nmol/L). These results suggest that circulating inhibin in men mainly originates from testis and that one of the routes of secretion is via the bloodstream.     

Lung to blood passage of human growth hormone after intratracheal instillation: stimulation of growth in hypophysectomized rats.

The passage from the lower respiratory tract into the blood of human GH (hGH; M(r) = 22,000) and bovine serum albumin (BSA; M(r) = 67,000) was assessed after intratracheal instillation in adult rats. The plasma level of immunoreactive hGH reached its maximum at 0.5-1 h after instillation and had almost disappeared within 24 h. Higher plasma levels were obtained in male rats than in female rats resulting in a higher total lung passage of hGH in male rats than in female rats (means +/- S.D.; 6.0 +/- 1.7% vs 3.3 +/-1.2%, P<0.01). The plasma level of BSA showed a different pattern, with a maximum at 16-24 h after instillation and a total lung passage of 4.3 +/- 1.7% of the given dose for both sexes. The plasma levels of hGH increased nonlinearly with increasing dose instilled in the dose range 36-720 micrograms/kg body weight. When hGH was instilled daily at a dose of 720 micrograms/kg body weight to hypophysectomized rats for 1 week, they responded with a significant increase in body weight when compared with hypophysectomized control rats (16.8 +/- 4.2 g vs -1.8 +/- 2.4 g, P<0.001). The results demonstrate that, despite their different molecular weights, hGH and BSA pass through the lower respiratory tract into the circulation with similar efficiencies in the rat. However, the lung passage of hGH, unlike that of BSA, showed sexual dependency, an earlier plasma concentration maximum and a tendency of the passage to saturation with increasing dose instilled.(ABSTRACT TRUNCATED AT 250 WORDS)     

Functional and morphologic changes in the lungs after a single intratracheal instillation of silica

The functional and morphologic consequences in the lungs of a single intratracheal instillation of silica dust were evaluated over 6 months. Male Fischer-344 rats were subjected to pulmonary function tests that measured lung volumes, forced expiratory flows, and carbon monoxide diffusing capacity (DLCO). Then saline (0.7 ml, n = 10) or saline containing either 10 mg (n = 9) or 40 mg (n = 14) of silica dust was instilled in the trachea, and each animal was tested 3, 12, and 24 wk later. Morphologic studies were performed on 27 rats similarly treated (3/group/time). By 3 wk after instillation, the inspiratory capacity, forced vital capacity, and DLCO diminished significantly (p less than 0.01) in the high-dose group. After 3 wk, the response tended to level off. Forced expiratory flows were not significantly affected. By contrast, biochemical analysis of lung collagen content indicated a linear accumulation throughout the experimental period. Microscopic evaluation revealed intra-alveolar accumulation of lipoproteinaceous material (alveolar proteinosis) by 3 wk in both dose groups, which persisted through the 24-wk experimental period. A few fibrotic nodules were seen as early as 3 wk in the 40-mg silica group, and their numbers increased with time, whereas they were relatively sparse in the 10-mg silica group throughout the experimental period, despite the diminished functional measurements. These data suggest a closer temporal correlation of the functional decrements observed to the evolution of the alveolar changes than they do to the development of fibrosis. We conclude that the development of nodular fibrosis was not the major contributing factor to the observed functional changes.     

Cerebral blood flow autoregulation and edema formation during pregnancy in anesthetized rats

Eclampsia is considered a form of hypertensive encephalopathy in which an acute elevation in blood pressure causes autoregulatory breakthrough, blood-brain barrier disruption, and edema formation. We hypothesized that pregnancy predisposes the brain to eclampsia by lowering the pressure of autoregulatory breakthrough and enhancing cerebral edema formation. Because NO production is increased in pregnancy, we also investigated the role of NO in modulating autoregulation. Cerebral blood flow autoregulation was determined by phenylephrine infusion and laser Doppler flowmetry. Four groups were studied: untreated nonpregnant (n=7) and late-pregnant (days 19 to 21; n=8) Sprague-Dawley rats and nonpregnant (n=8) and late-pregnant (n=8) animals treated with an NO synthase inhibitor (N(G)-nitro-l-arginine methyl ester; 0.5 to 0.7 g/L). Brain water content and blood-brain barrier permeability to sodium fluorescein were determined after breakthrough. Pregnancy caused no change in autoregulation or the pressure of breakthrough. However, treatment with the NO synthase inhibitor significantly increased the pressure of autoregulatory breakthrough (nonpregnant: 183.6+/-3.0 mm Hg versus 212.0+/-2.8 mm Hg, P<0.05; late-pregnant: 180.8+/-3.2 mm Hg versus 209.3+/-4.7 mm Hg, P<0.05). After autoregulatory breakthrough, only late-pregnant animals showed a significant increase in cerebral edema formation, which was attenuated by NO synthase inhibition. There was no difference in blood-brain barrier permeability between nonpregnant and late-pregnant animals in response to acute hypertension, suggesting that pregnancy may predispose the brain to eclampsia by increasing cerebral edema through increased hydraulic conductivity.     

Sex steroid metabolism in human peripheral blood mononuclear cells changes with aging

CONTEXT: Dehydroepiandrosterone (DHEA) mainly exerts indirect action via downstream conversion toward sex steroids within peripheral target cells including immune cells. In vitro DHEA has been shown to enhance IL-2 release from T lymphocytes, whereas it inhibits IL-6 secretion. Conversely, aging is associated with a decline in both DHEA and IL-2, whereas IL-6 increases. OBJECTIVE: The objective of the study was to investigate age-related differences in expression and functional activity of steroidogenic enzymes involved in downstream conversion of DHEA in peripheral blood mononuclear cells (PBMCs). DESIGN: This study was cross-sectional. PARTICIPANTS/SETTING: Healthy young men (n = 8; age range, 23-29 yr) and healthy middle-aged men (n = 8; age range, 52-66 yr) were studied in an academic setting. MEASURES: mRNA expression of steroidogenic enzymes in PBMCs was measured by qualitative and quantitative RT-PCR analysis and enzyme activity assays after incubation of PBMCs with radiolabeled DHEA, 4-androstene-3,17-dione (androstenedione), and testosterone. RESULTS: RT-PCR analysis showed expression of all enzymes required for DHEA conversion toward active androgens and to the immune-stimulatory metabolite androstenediol. Steroid conversion patterns indicated a particularly increased activity of 17beta-hydroxysteroid dehydrogenase type 5 (17beta-HSD5) in the older men, demonstrated by significantly higher conversion rates of DHEA to androstenediol and of androstenedione to testosterone (all P < 0.05). By contrast, conversion of DHEA to androstenedione via 3beta-HSD occurred at a similar rate. Quantitative RT-PCR analysis revealed increased expression of 17beta-HSD 5 mRNA in PBMCs from the older men. CONCLUSIONS: Our results provide evidence for significant changes in sex steroid metabolism by human PBMCs with aging, which may represent an endocrine link to immune senescence.     

Ovarian and peripheral blood inhibin concentrations increase with gonadotropin treatment in immature rats

The effects of PMSG treatment on ovarian and circulating inhibin concentrations in immature female rats has been examined. Sixty-four hours after injection of 10, 20 or 40 IU of PMSG the animals were anesthetized with ether; ovaries, uteri and blood from the abdominal aorta were collected. Steroid-free extracts of ovary and serum samples were prepared and assayed quantitatively for inhibin activity in an in vitro bioassay system. PMSG treatment elevated (p less than 0.001) both uterine and ovarian wt, and ovarian and peripheral concentrations of inhibin. A dose-related increase occurred ovarian wt, and in peripheral and ovarian content of inhibin. Ovarian inhibin concentration increased with dose of PMSG until the highest dose, where a significant decline and luteinization were seen. Peripheral FSH levels were significantly lowered at all doses of PMSG treatment; in contrasts, LH was significantly elevated, due to cross-reaction of PMSG in the LH assay. These results show that both ovarian and circulating levels of inhibin are related to the degree of gonadotropic stimulation, supporting the view that inhibin is involved in folliculogenesis and in the feedback regulation of FSH.     

Cyclosporin A-associated changes in red blood cell membrane composition, deformability, blood and plasma viscosity in rats

Most of the studies concerning the effects of cyclosporin A (Cs A) on red blood cell (RBC) rheology were carried out in human transplant recipients who may still have residual insufficiency and concomitant administration of other immunosuppressive and antihypertensive drugs. The aim of this study is to evaluate the effects of Cs A on red cell rheology and membrane composition in nontransplant healthy rats. Female Wistar albino rats were divided into two groups of 10 animals each. Rats received 10 mg/kg Cs A, i.p. or saline for 4 weeks. Cs A administration significantly increased the RBC deformability, and plasma and blood viscosity (p < 0.001, p < 0.01 and p < 0.01, respectively). Cs A administration to the rats increased RBC membrane cholesterol (CHO) levels and the CHO/phospholipid (PL) ratio significantly (p < 0.01 and p < 0.05, respectively) but did not change RBC membrane proteins and membrane PL levels. These results suggest that Cs A changes the rheological functions of RBC and lipid content of RBC membrane in healthy rats and thereby it may play an important role in the regulation of microcirculation.     

丁基苯酞对重型弥漫性脑创伤大鼠脑血流量及脑水肿的影响

目的 观察丁基苯酞对脑创伤后大鼠脑血流量及脑水肿的影响.方法 191只成年雄性Sprague-Dawlley大鼠,体重(330 ±20)g,随机(随机数字法)分为对照组(40只)、模型组(57只)、低剂量丁基苯酞干预组(57只,剂量80 mg/kg),高剂量丁基苯酞干预组(剂量120 mg/kg).各组分别在伤后3、6、24、48、72 h每组取4只大鼠应用激光多普勒血流计观察脑组织血流量变化;伊文思蓝法标记微血管通透性;干湿法测定脑组织含水量.采用SPSS 17.0对实验数据进行统计分析,正常对照组与模型组脑血流量、脑组织水含量、伊文思蓝透过量和含量比较采用析因设计资料的方差分析,组内分析采用SNK-q分析,P＜0.05为差异有统计学意义.结果 与模型组比较,丁基苯酞干预组中,6、24、48、72 h脑血流血量增加(q=23.37 ～ 26.10,P＜0.05);伊文思蓝含量降低(q=3.53～25.55,P＜0.05);脑组织含水量降低(q=23.37 ～ 26.10,P＜0.05);高剂量丁基苯酞干预组上述指标变化在更为显著(q =6.59 ～8.96,7.52 ～8.53,7.89～ 20.78,P＜0.05).结论 丁基苯酞增加脑创伤后大鼠脑血流量,减轻血管通透性和脑水肿,对重型脑创伤有保护作用.     

自发性高血压大鼠脑出血急性期中枢和外周肾上腺素能受体表达与血压调控的相关性研究

目的 观察自发性高血压大鼠(spontaneously hypertensive rat,SHR)脑出血后血压变化以及中枢(脑组织)-肾上腺素能受体(adrenergic receptor,AR)和外周(肾组织)α1A-AR的表达,探讨高血压脑出血急性期α1A-AR和α2A-AR与血压调控的相关性.方法 30只6月龄雄性SHR,随机分为假手术组和脑出血1 d、3 d、7 d和14 d组,每组6只.尾袖法测定血压;尾壳核注入Ⅳ型胶原酶建立脑出血模型;逆转录聚合酶链反应和免疫组织化学染色法检测α2A-AR和α2A-AR mRNA和蛋白表达.结果 脑出血后1 d时血压为(195.4 ±8.39)mm Hg,显著高于出血前的(177.8±8.69)mm Hg(P=0.00)和假手术组的(184.1±3.76)mm Hg(P=0.002),3 d时为(185.3±9.22)mm Hg,较1 d时下降,7 d和14d时分别为(177.7±5.62)mm Hg和(176.67±6.06)mm Hg,基本恢复至出血前水平.肾组织α2A-AR mRNA和蛋白在脑出血后1 d时分别为(0.91±0.013)和(0.944±0.142)%,高于假手术组的(0.89±0.018)和(0.779±0.103)%,3 d时达高峰,为(0.93±0.015)(P=0.008)和(1.526 ±0.296)%(P=0.010);(3)脑出血3 d时脑组织俚α2A-AR mRNA和蛋白为(0.93±0.020)和(2.64±0.293)%,显著高于假手术组的(0.86 ±0.019)(P=0.001)和(1.070±0.155)%(P=0.020)以及脑出血1 d时的(0.87±0.029)(P=0.000)和(1.629±0.488)%(P=0.023).脑出血1 d组～7 d组血压变化与脑组织α2A-AR mRNA吸光度的相关系数r=-0.509(P=0.031),与脑组织α2A-AR蛋白表达容积分数的相关系数r=-0.473(P=0.047).结论 急性脑出血的血压调控可能与脑组织α2A-AR和肾组织α2A-AR表达上调有一定的相关性.     

Pergolide-induced dyspnea, bilateral pleural effusion and peripheral edema

A patient with severe Parkinson's disease presented with increasing dyspnea, bilateral pleural effusion and peripheral edema that were refractory to diuretic therapy and were first misdiagnosed as signs of right-sided heart failure. Pergolide was the only culprit for this devastating condition and on its discontinuation all signs of fluid retention resolved. In this report, drug reactions to ergots and dopamine agonists are discussed.     

HBV 侵犯PBMC致线粒体功能改变

目的探讨ＨＢＶ侵犯外周血单个核细胞（ＰＢＭＣ）后对其线粒体功能的影响．方法ＨＢｓＡｇ阳性６个月以上，无肝炎症状及体征，肝功正常患者５８例．多聚酶链反应检测ＰＢＭＣ中ＨＢＶＤＮＡ，噻唑兰（ＭＴＴ）比色法测线粒体功能．ＨＢｓＡｇ、ＨＢｅＡｇ检测用固相放免法检测．结果慢性ＨＢＶ感染者５８例，ＰＢＭＣ中检出ＨＢＶＤＮＡ３１例（５３５％），ＰＢＭＣ中ＨＢＶＤＮＡ阳性组ＭＴＴ比色法查线粒体功能的Ａ（ＯＤ５００ｎｍ）值明显低于ＨＢＶＤＮＡ阴性组（００５±００３ｖｓ０２９±００７，Ｐ＜００１）．结论慢性ＨＢＶ感染时，ＨＢＶ常侵犯ＰＢＭＣ，并导致ＰＢＭＣ线粒体功能降低、能量代谢异常．这可为ＨＢＶ慢性感染免疫功能异常的原因之一．