冠状动脉搭桥术早期并发症及死亡率(附196例报告)

1985年1月～1987年12月作者于荷兰格罗宁根医学科学院心胸外科主做了196例冠状动脉搭桥术。术后早期死亡2例(1.0％)、内出血3例(1.5％)、胸骨裂开2例(1.0％)、心律紊乱40例(20.4％)、围手术期心肌梗塞5例(2.6％),本文就术后早期并发症进行了讨论。     

Acute cardiovascular toxic effects of copper in anesthetized rabbits

Copper deficiency is linked to many types of cardiovascular diseases. Copper toxicity may not be common, but it produces cardiac problems and even lethality. However, little is known about the precise mechanism of cardiotoxic action of copper in mammals. In an effort to characterize the cardiovascular effects and potential toxic action of copper, white New Zealand rabbits were instrumented for the measurement of cardiovascular parameters under urethane anesthesia. Left ventricular pressure and its dP/dt as well as the sympathetic efferent renal nerve activity were also monitored continuously before, during and after the injection of various doses of copper. Low doses of copper (3 mg/kg or less) increased blood pressure with a slight reduction in heart rate. There was also a transient increase in cardiac contractile force as shown by an increase of dP/dt with a reduction in sympathetic renal efferent nerve activity. However, high doses of copper (10 mg/kg or higher) decreased these cardiac parameters, which led to a state of shock, 90 seconds after the copper treatment. There was a compensatory increase in respiration rate and renal nerve activity during the shock. Thus, the data suggest that copper initially activates peripheral organs such as the heart and subsequently produces a distinct inhibitory action on sympathetic outflow, which is related to the toxic action of this metal.     

Apports des explorations vasculaires ultrasonores à l''étude des néphropathies chez l''enfant

The proximity of child's kidneys from the cutaneous surface allows a particularly sensitive exploration by doppler sonography, which in addition has the major advantage of being a non-invasive, non-irradiating and painless technique. However there are two limitations to this technique: the lack of cooperation of some children and the still limited availability of high quality equipment in intensive care units. Indeed most of the applications described in this paper (ie. pyelonephritis, renovascular hypertension, tumors, acute renal insufficiency and renal vein thrombosis) require, besides an experienced operator, expensive power doppler equipment including high frequency and high resolution probes.     

Impact of Solvent on Electrospinning of Zein and Analysis of Resulting Fibers

Zein fibers have been produced by electrospinning from acetic acid, aqueous methanol, ethanol and isopropyl alcohol. Alcohol solutions produced fibers that were predominantly ribbons. Fibers spun from acetic acid solution have a round morphology with a narrower distribution of diameters when spun under suitable conditions. The IR spectra of electrospun fibers display increased absorbance at 1 650 cm^?1 relative to starting material, indicative of increased α‐helical structure. Raman spectra of fibers spun from acetic acid solution had spectral differences, having increased absorbance at 680, 750 and 860 cm^?1, versus fibers spun from alcoholic solvents suggesting different tertiary structure within the fiber, which may result from different structures in solution. Polarized Raman spectroscopy taken parallel and perpendicular to the fiber axis displayed no differences, suggesting similar secondary and tertiary structures in these directions. All of the fibers had some degree of birefringence demonstrating the presence of orientation. The smaller fibers were highly birefringent throughout the fiber, while the larger fibers had orientation at the surface only. Quality fibers could not be produced from N,N‐dimethylformamide, acetone/water, acetic acid/water, 8 M urea/water or 10% NaOH/water zein solutions.

     

Direct demonstration that autologous bone marrow transplantation for solid tumors can return a multiplicity of tumorigenic cells

Patients with solid tumors are increasingly being treated by autologous bone marrow transplantation (BMT). Although response rates appear to be increased, disease recurrence is the commonest cause of treatment failure. Whether relapse is entirely due to residual disease in the patient or arises also from infiltrating malignant cells contained in the autologous marrow transplant has not been resolved. If the latter explanation is correct, then purging would be required as part of the transplantation procedure. We used retrovirally mediated transfer of the neomycin-resistance gene to mark BM harvested from eight patients with neuroblastoma in clinical remission. The marked marrow cells were subsequently reinfused as part of an autologous BMT. At relapse, we sought the marker gene in malignant cell populations. Three patients have relapsed, and in each the marker gene was detected by phenotypic and genetic analyses of resurgent malignant cells at medullary and extramedullary sites. Analysis of neuroblast DNA for discrete marker gene integration sites suggested that at least 200 malignant cells, each capable of tumor formation, were introduced with the autologous marrow transplant and contributed to relapse. Thus, autologous BMTs administered to patients with this solid tumor may contain a multiplicity of malignant cells that subsequently contribute to relapse. The marker-gene technique we describe should permit evaluation of the mechanisms of relapse and the efficacy of purging in patients receiving autologous marrow transplantation for other solid tumors that infiltrate the marrow.     

Lactobacillus rhamnosus CNCM I-3690 and the commensal bacterium Faecalibacterium prausnitzii A2-165 exhibit similar protective effects to induced barrier hyper-permeability in mice

Impaired gut barrier function has been reported in a wide range of diseases and syndromes and in some functional gastrointestinal disorders. In addition, there is increasing evidence that suggests the gut microbiota tightly regulates gut barrier function and recent studies demonstrate that probiotic bacteria can enhance barrier integrity. Here, we aimed to investigate the effects of Lactobacillus rhamnosus CNCM I-3690 on intestinal barrier function. In vitro results using a Caco-2 monolayer cells stimulated with TNF-α confirmed the anti-inflammatory nature of the strain CNCM I-3690 and pointed out a putative role for the protection of the epithelial function. Next, we tested the protective effects of L. rhamnosus CNCM I-3690 in a mouse model of increased colonic permeability. Most importantly, we compared its performance to that of the well-known beneficial human commensal bacterium Faecalibacterium prauznitzii A2-165. Increased colonic permeability was normalized by both strains to a similar degree. Modulation of apical tight junction proteins expression was then analyzed to decipher the mechanism underlying this effect. We showed that CNCM I-3690 partially restored the function of the intestinal barrier and increased the levels of tight junction proteins Occludin and E-cadherin. The results indicate L. rhamnosus CNCM I-3690 is as effective as the commensal anti-inflammatory bacterium F. prausnitzii to treat functional barrier abnormalities.