体外膜肺氧合技术支持治疗期间患者血乳酸浓度及其预后

目的:探讨体外膜肺氧合支持治疗患者血乳酸浓度的变化和预后。方法:于2004-12/2006-09在中国医学科学院阜外心血管病医院因脱离体外循环困难的心脏外科术后患者、扩张性心肌病和冠状动脉粥样硬化性心脏病发生心源性休克的患者共40例进行了体外膜肺氧合支持治疗,按年龄和存活预后分为4组:成人存活组、成人死亡组、儿童存活组、儿童死亡组。分析4组的治疗效果,分别抽取各组患者体外膜肺氧合建立时、体外膜肺氧合运转6h、运转中间时点、停机前6h、停机时的血乳酸浓度。结果:①体外膜肺氧合支持治疗患者40例,成人组26例,20例脱机,16例生存,10例死亡,脱机率76.9%,生存率61.5%;儿童组14例,7例脱机,5例生存,9例死亡,脱机率50.0%,生存率35.0%。②成人或儿童存活组的乳酸浓度都与死亡组有明显差别,存活组血乳酸浓度明显低于死亡组,其中建立和运转6h、中间时点的差异有显著性意义(P<0.05),其余2个时点的差异有非常显著性意义(P<0.001)。组内与建立时比较,中间时点、停止前6h、停止时差异均有显著性意义(P<0.001),血乳酸浓度逐渐降低。结论:经体外膜肺氧合支持治疗的患者,血乳酸浓度明显下降,脱机时血乳酸仍高的患者预后不良。     

血管内皮细胞生长因子和c-Fos在单基因遗传自然发病型糖尿病小鼠颌下腺中的表达

目的:观察血管内皮细胞生长因子和c-Fos蛋白在db/db自发性糖尿病小鼠颌下腺的表达,及其与糖尿病病程和颌下腺形态学改变的关系。方法:实验于2004-05在承德医学院中心实验室和承德医学院附属医院病理科完成。取3,4,6,8,10月龄db/db(单基因遗传自然发病型)糖尿病小鼠颌下腺(实验组)及相应月龄的db/ m正常小鼠颌下腺(对照组),采用SP免疫组化染色,观察颌下腺血管内皮细胞生长因子、c-Fos阳性表达的变化。结果:①颌下腺血管内皮细胞生长因子阳性细胞数目:实验组3,4,6,8,10月龄高于相应对照组[(11.8±3.35),(17.4±2.61),(20.6±1.92),(26.8±4.85),(28.0±4.22)个/视野;(6.6±0.89),(11.8±1.64),(16.2±3.27),(16.4±3.97),(17.6±1.82)个/视野,P<0.05,0.01],且呈逐渐增加趋势。②颌下腺c-Fos阳性细胞数目:实验组3,4,6月龄低于相应对照组[(6.4±0.65),(7.8±0.84),(7.9±0.65)个/视野;(12.2±0.84),(11.4±0.55),(10.8±0.84)个/视野,P<0.01]。③糖尿病病程的延长,实验组下颌下腺的实质细胞有明显形态学改变,其中腺泡萎缩明显,细胞排列紊乱。结论:①血管内皮细胞生长因子表达在db/db糖尿病小鼠颌下腺中随病程延长表达增加,与糖尿病病程呈正相关。②db/db糖尿病状态下颌下腺实质发生萎缩性形态学变化,颌下腺细胞表达c-Fos蛋白明显降低,可能与其密切相关。     

Causes and predictors of nonresponse to treatment of intensive care unit-acquired pneumonia

OBJECTIVE: To prospectively evaluate the predictive factors for the nonresponse to empirical antibiotic treatment and mortality in patients with intensive care unit-acquired pneumonia. DESIGN: A 1-yr prospective cohort of patients with suspicion of intensive care unit-acquired pneumonia. SETTING: Five medical and surgical intensive care units of Hospital Clinic in Barcelona. PATIENTS: A total of 71 patients with intensive care unit-acquired pneumonia were studied. The definition of nonresponse included at least one of the following: failure to improve the Pao2/Fio2 ratio or need of intubation because of pneumonia, persistence of fever or hypothermia and purulent respiratory secretions, worsening of pulmonary infiltrates, or occurrence of septic shock or multiple organ dysfunction not present at onset of pneumonia. INTERVENTIONS: Clinical assessment, including severity scores, blood and quantitative cultures of respiratory secretions, and cytokine measurements in serum and bronchoalveolar lavage at onset of pneumonia and 72 hrs after antimicrobial treatment. MEASUREMENTS AND RESULTS: A total of 44 patients (62%) fulfilled criteria of nonresponse, and at least one cause of nonresponse could be determined in 28 cases (64%): inappropriate treatment in ten (23%), superinfection in six (14%), concomitant foci of infection in 12 (27%), and noninfectious causes in seven cases (16%). The remaining 16 patients with no definite cause of nonresponse presented with septic shock, multiple organ dysfunction, or acute respiratory distress syndrome. Increased levels of interleukin-6 at onset of pneumonia (odds ratio, 9.7; p =.014) was an independent predictor of nonresponse to treatment. Likewise, increased level of interleukin-6 at follow-up (odds ratio, 27; p =.001) was the only independent predictor for hospital mortality. CONCLUSION: Increased systemic inflammatory response was the main predictor of nonresponse to treatment and mortality.     

Insulin and glucagon degradation in liver are not affected by hepatic cirrhosis

Hyperinsulinemia and impaired glucose tolerance are associated with liver cirrhosis. To investigate whether insulin-degrading activity in liver tissue plays a role in hyperinsulinemia, we assayed this activity in biopsy tissue from healthy and cirrhotic subjects. There was no difference in insulin degradation between these two groups. Also glucagon-degrading activity in liver tissue, which is catalyzed by the same enzyme as insulin-degrading activity, did not differ between the two groups studied. Therefore, insulin-degrading activity does not appear to be involved in the hyperinsulinemia that occurs in liver cirrhosis. The study provides indirect evidence that hyperinsulinemia and impaired glucose metabolism in liver cirrhosis are due to different mechanisms (receptorial and post-receptorial defects, and altered feedback inhibition of insulin secretion).     

Low‐intensity treadmill exercise‐related changes in the rat stellate ganglion neurons

Stellate ganglion (SG) represents the main sympathetic input to the heart. This study aimed at investigating physical exercise–related changes in the quantitative aspects of SG neurons in treadmill‐exercised Wistar rats. By applying state‐of‐the‐art design‐based stereology, the SG volume, total number of SG neurons, mean perikaryal volume of SG neurons, and the total volume of neurons in the whole SG have been examined. Arterial pressure and heart rate were also measured at the end of the exercise period. The present study showed that a low‐intensity exercise training program caused a 12% decrease in the heart rate of trained rats. In contrast, there were no effects on systolic pressure, diastolic pressure, or mean arterial pressure. As to quantitative changes related to physical exercise, the main findings were a 21% increase in the fractional volume occupied by neurons in the SG, and an 83% increase in the mean perikaryal volume of SG neurons in treadmill‐trained rats, which shows a remarkable neuron hypertrophy. It seems reasonable to infer that neuron hypertrophy may have been the result of a functional overload imposed on the SG neurons by initial posttraining sympathetic activation. From the novel stereological data we provide, further investigations are needed to shed light on the mechanistic aspect of neuron hypertrophy: what role does neuron hypertrophy play? Could neuron hypertrophy be assigned to the functional overload induced by physical exercise? © 2008 Wiley‐Liss, Inc.     

Stereological and biochemical analysis of muscular and connective tissue components in the penile corpus cavernosum adjacent to the fibrous plaque of Peyronie's disease

OBJECTIVE

To investigate the structural organization of the connective tissue in the corpus cavernosum (CC) adjacent to the fibrous plaque in Peyronie’s disease (PD) using stereological and biochemical techniques, as most studies on PD have focused on the analysis of the fibrous plaque that forms in the tunica albuginea (TA). Because this fibrotic reaction is mediated by various inflammatory soluble factors, adjacent connective tissues might also be affected and this secondary effect might explain, for example, the erectile dysfunction that occurs in PD.

PATIENTS AND METHODS

During surgery biopsies were taken from the CC adjacent to the fibrous plaque and from the plaque itself in seven patients with PD (mean age 48.3 years). All the patients had normal erections. Control samples were similarly located samples from ‘normal’ penises obtained during autopsy of five men (mean age 52.3 years). Tissue samples were stained with Weigert’s stain (elastic fibres), Van Gieson’s stain (connective tissue), and Sirius red (collagen). Stereological analysis was done using a 42‐point grid to determine volumetric densities (Vv). Total collagen content was estimated as micrograms of hydroxyproline per milligram dry CC.

RESULTS

The Vv of elastic fibres was significantly reduced in PD by 17.3% compared with controls, at a mean (sd ) of 19.49 (3.27)% vs 23.56 (1.87)% (P < 0.05). While in PD the Vv of smooth muscle at 34.46 (2.06)% and connective tissue at 35.39 (6.15)% were not significantly different from those of controls at 38.38 (3.17)% and 38.02 (5.03)%, respectively. The Vv of elastic fibres in the fibrous plaque was decreased by 38.3% compared with the normal TA, at 20.25 (5.49)% vs 32.81 (4.75)% (P < 0.02). The mean (sd ) collagen concentration in the CC from controls was 77.94 (24.26) µg/mg and in the patients with PD was 66.57 (19.39) µg/mg, which did not differ significantly. Sirius red‐stained sections under polarized light showed that, in the normal CC, collagen‐associated colours were homogeneously distributed. However, in the PD samples, stained collagen had a disrupted orientation and had a more heterogeneous birefringence, implying looser collagen bundles.

CONCLUSIONS

The quantitative analyses indicated that collagen in the CC close to the fibrous plaque was not affected, although its organization was noticeably altered. The CC elastic fibres were reduced though, and there was a similar change in the fibrous plaque of the TA. These results suggest that, although occurring primarily in the TA, the PD fibrous plaque may induce changes in the adjacent CC.