Insights into the assessment of myocardial perfusion offered by different cardiac imaging modalities

Myocardial perfusion may be very broadly defined as the tightly regulated nutrient delivery to cardiac tissue. The different components of perfusion are myocardial blood flow, oxygen delivery, myocardial oxygen consumption, and myocardial blood volume. Historically, focus has been placed mostly on the assessment of blood flow. In many instances, knowledge of flow without information about these other aspects is inadequate. This review discusses the various cardiac imaging techniques used for the assessment of myocardial perfusion that represent diverse physiologic measures of “perfusion.” Their strengths and limitations are discussed as is their relevance to specific clinicopathologic conditions. Significant work still needs to be performed before all the aspects of myocardial perfusion can be precisely measured in human beings. Supported in part by a grant (R01-HL48890) from the National Institutes of Health, Bethesda, Md. Dr. Lindner is the recipient of a Fellowship Training Grant from the Virginia Affiliate of the American Heart Association, Glen Allen, Va. Dr. Kaul is an Established Investigator of the National Center of the American Heart Association, Dallas, Texas.     

高位腰椎间盘突出症

目的：通过147例高位腰椎间盘突出症的回顾性研究,旨在提高对本症的认识,减少漏诊,误诊,方法：回顾性分析报告147例高位腰椎间盘突出,结果：治疗腰1,210例,腰2。3 32例,腰3,4 105例,其中双间隙突出34例,跳跃性突出27例,伴椎管狭窄31例。瘫痪3例,非手术治疗34例,手术113例,优47例,良8例,差92例,重点讨论了高位腰椎及椎间盘和神经根的解剖特点和临床三大特征及诊断治疗,提出对不同程度的病人用不同治疗方式以及手术中需要注意的六个问题。     

Influence of microbubble surface charge on capillary transit and myocardial contrast enhancement

OBJECTIVE: The goal of the study was to determine whether microbubble charge influences the microvascular retention of microbubble contrast agents. BACKGROUND: Interactions between serum proteins and lipid membranes are greater with anionic compared with neutral membranes. These interactions may influence the microvascular behavior of anionic lipid microbubbles. METHODS: Intravital microscopy of the cremaster muscle was performed in six wild-type mice and three C3-deficient mice during intravenous injection of lipid-shelled microbubbles with either a neutral or a negative charge. Both agents were prepared with and without a protective surface layer of polyethyleneglycol (PEG). Complement attachment to microbubbles was assessed by flow cytometry with flourescein isothiocyanate-conjugated anti-C3b monoclonal antibody. Myocardial contrast echocardiography was performed in six dogs to assess pulmonary and myocardial retention of microbubbles. RESULTS: Size-independent capillary retention of microbubbles, occurring for a few seconds to >10 min, was frequently observed with anionic, but rarely with neutral, microbubbles (4.3 +/- 0.3 vs. 0.4 +/- 0.1 mm(-3), p < 0.01). Anionic microbubble retention was reduced by 70% by surface PEG and was also markedly reduced in C3-deficient mice (1.4 +/- 0.1 mm(-3), p < 0.05 vs. wild-type). Flow cytometry demonstrated complement attachment to only anionic microbubbles. Contrast echocardiography indicated both pulmonary and myocardial retention of only anionic microbubbles, the latter evidenced by persistent opacification >10 min after bolus intravenous injection. CONCLUSIONS: Lipid microbubbles with a net negative charge can be retained within capillaries via complement-mediated attachment to endothelium. This property may be useful for the development of ultrasound contrast agents that can be imaged late after venous injection.     

Olfactory Bulb D2/D3 Receptor Availability after Intrastriatal Botulinum Neurotoxin-A Injection in a Unilateral 6-OHDA Rat Model of Parkinson’s Disease

Olfactory deficits occur as early non-motor symptoms of idiopathic Parkinson’s disease (PD) in humans. The first central relay of the olfactory pathway, the olfactory bulb (OB), depends, among other things, on an intact, functional crosstalk between dopaminergic interneurons and dopamine receptors (D₂/D₃R). In rats, hemiparkinsonism (hemi-PD) can be induced by unilateral injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle (MFB), disrupting dopaminergic neurons of the substantia nigra pars compacta (SNpc). In a previous study, we showed that subsequent injection of botulinum neurotoxin-A (BoNT-A) into the striatum can reverse most of the pathological motor symptoms and normalize the D₂/D₃R availability. To determine whether this rat model is suitable to explain olfactory deficits that occur in humans with PD, we examined the availability of D₂/D₃R by longitudinal [¹⁸F]fallypride-PET/CT, the density of tyrosine hydroxylase immunoreactivity in the OB, olfactory performance by an orienting odor identification test adapted for rats, and a connectome analysis. PET/CT and immunohistochemical data remained largely unchanged after 6-OHDA lesion in experimental animals, suggesting that outcomes of the 6-OHDA hemi-PD rat model do not completely explain olfactory deficits in humans. However, after subsequent ipsilateral BoNT-A injection into the striatum, a significant 8.5% increase of the D₂/D₃R availability in the ipsilateral OB and concomitant improvement of olfactory performance were detectable. Based on tract-tracing meta-analysis, we speculate that this may be due to indirect connections between the striatum and the OB.     

蒙药如达溃疡散对大鼠乙酸性胃溃疡及其血清促胃液素的影响

目的:探讨如达溃疡散对大鼠乙酸性胃溃疡的作用及对其血清促胃液素(gastrin)含量的影响.方法:采用乙酸法复制胃溃疡模型,将大鼠随机分为对照组、如达溃疡散组、雷尼替丁组,观察如达溃疡散对大鼠胃溃疡的作用,并检测其对大鼠血清中促胃液素含量的影响.结果:与对照组相比,如达溃疡散能明显抑制溃疡的发生,抑制血清促胃液素含量.结论:如达溃疡散具有抗胃溃疡的作用,其作用机理可能是通过抑制促胃液素释放,进一步减少胃酸分泌来实现的.     

Severe pulmonary vascular occlusive disease following bone marrow transplantation in Omenn syndrome

A 5-month-old infant presented with severe combined immunodeficiency disease, reticuloendotheliosis, and hypereosinophilia (Omenn syndrome) resulting in recurrent infections and endomyocardial disease. Bone marrow transplantation from an HLA-identical donor after chemotherapeutic conditioning led to both immunological and clinical recovery. Bone marrow transplantation, however, was followed by severe pulmonary occlusive disease. The patient gradually recovered while on increased inspiratory oxygen and the calcium channel blocker nifedipine.     

Kombinierte GnRH-Agonist/hMG-Therapie und ovarielles Überstimulationssyndrom

Ohne Zusammenfassung     

An outbreak of Salmonella blockley infections following smoked eel consumption in Germany

In June 1998, an increased number of persons with Salmonella blockley infection were reported from one German state. Because S. blockley is extremely uncommon in Germany, a case-control study was performed in order to find the source. A total of 13 patients met the case definition. Nine of 12 cases and 2 of 21 controls with food consumption histories reported eating smoked eel (OR 28.5; 95% CI 3.9-235.3). The consumed eel came from four different local smokeries, but could be traced back to fish farms in Italy. This outbreak indicates that eel may be a vehicle for salmonella infection and that the smoking process may not eliminate bacterial contamination from raw fish.