Normal-phase high-performance liquid chromatograms of retinal, retinol and retinyl palmitate isomers using n-heptane-tert.-butyl methyl ether as mobile phase are presented. Methods for the synthesis of various isomers of these retinoids are described. This enables one to produce standard chromatograms and to select various isomers for cochromatography and the identification of the various peaks under study. Assignment of the peaks is based on chromatograms published previously in this journal. For the main isomers it is possible to get baseline separation of the commonly occurring isomeric forms in a reasonably short analysis time.

Chromatography, High Pressure Liquid↗

PubMed2000

Efficient gene transfer into primary human CD8+ T lymphocytes by MuLV-10A1 retrovirus pseudotype.

Efficient and stable gene transfer into primary human T lymphocytes would greatly improve their use for adoptive transfer to treat acquired disorders, viral diseases, and cancer. We have constructed retroviral vector pseudotypes of amphotropic murine leukemia viruses (A-MuLV, MuLV-10A1), gibbon ape leukemia virus (GaLV), and feline endogenous virus (RD114) containing the enhanced green fluorescent protein (GFP) as a marker gene. Transduction of primary human CD8+ T lymphocytes by the different GFP-retrovirus pseudotypes revealed the superiority of MuLV-10A1 in comparison with A-MuLV, GaLV, and RD114, respectively. The superior transduction efficacy of CD8+ T cells by MuLV-10A1 correlates with a longer half-life of this pseudotype in comparison with A-MuLV and, as shown by interference analysis with the human T cell line HUT78, by the utilization of both the A-MuLV receptor (Pit2) and the GaLV receptor (Pit1) for cell entry.

CD8-Positive T-Lymphocytes↗

PubMed2000

Three-dimensional reconstruction of a large venous bypass graft aneurysm supplying 2 coronary arteries.

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Adult↗

PubMed2000

Delta-opioid receptor-mediated increase in cortical extracellular levels of cholecystokinin-like material by subchronic morphine in rats.

Numerous pharmacological data indirectly support the idea that interactions between cholecystokinin (CCK) and opioids participate in the development of tolerance to morphine. Biochemical investigations were performed with the aim of directly assessing the status of such interactions in morphine treated rats. Tolerance to the alkaloid after s.c. implantation of morphine pellets for three days was not associated with any change in the levels of both CCK like-material (CCKLM) and proCCK mRNA in the frontal cortex. However, microdialysis in the freely moving rat showed that this morphine treatment produced a significant increase (+40%) of the cortical spontaneous CCKLM outflow, which could be completely prevented by intracortical infusion of naloxone (10 microM). The opioid receptors responsible for morphine-induced cortical CCKLM overflow appeared to be of the delta type because intracortical infusion of selective delta-opioid receptor antagonists such as naltriben (10 microM) and 7-benzylidenenaltrexone (10 microM) also prevented the effect of morphine, whereas CTOP (10 microM), a selective mu-opioid receptor antagonist, and nor-binaltorphimine (10 microM), a selective K-opioid receptor antagonist, were inactive. These data indicate that morphine tolerance is associated with delta-opioid receptor mediated activation of cortical CCKergic systems in rats.

Analgesics, Opioid↗

PubMed2000

Acute left colonic diverticulitis--compared performance of computed tomography and water-soluble contrast enema: prospective evaluation of 420 patients.

PURPOSE: The most valuable radiologic examination to be done initially when acute left colonic diverticulitis is suspected is still a matter of controversy. This study compares the performance between water-soluble contrast enema and computed tomography. METHODS: From 1986 to 1997, all patients admitted in our emergency center with clinically suspected left-colonic diverticulitis had a contrast enema and a computed tomography within 72 hours of their admission, unless clinical findings required immediate laparotomy. They were prospectively included in the study if one or both radiologic examinations showed signs of acute diverticulitis or diverticulitis was surgically removed and histologically proven or both. Diverticulitis was considered moderate when computed tomography showed localized thickening of the colonic wall (5 mm or more) and inflammation of pericolic fat and contrast enema showed segmental lumen narrowing and tethered mucosa; it was considered severe when abscess or extraluminal air or contrast or all three were observed on computed tomography and when one or both of the last two signs were seen on contrast enema. Of 542 patients, 420 who had both computed tomography and contrast enema entered the study. RESULTS: The performance of computed tomography was significantly superior to contrast enema in terms of sensitivity (98 vs. 92 percent; P = 0.01), which was calculated from patients who had their colon removed and whose diverticulitis was histologically proven, and in the evaluation of the severity of the inflammation (26 vs. 9 percent; P = 0.02). Moreover, of 69 patients who had an associated abscess seen on computed tomography, only 20 (29 percent) had indirect signs of this complication on contrast enema. CONCLUSIONS: In the diagnostic evaluation of acute left-colonic diverticulitis, computed tomography should be preferred to contrast enema as the initial radiologic examination because of its statistically significant superiority in sensitivity and for its significantly better performance in the detection of severe infection, especially when an abscess is associated with the disease.

Abscess↗

PubMed2000

[CT-assisted volumetry and densitometry of distraction osteogenesis lengthened mandibular areas].

Gradual callus distraction in the correction of hypoplastic areas in the viscerocranial skeleton is an established method due to its efficacy. Whereas functional and esthetical improvements can be seen easily, it is impossible to get the increase of the bony mass right using the distractor scale or by clinical investigation. Only in animal studies can volumetric and densitometric measurements be done directly. By permission of the local ethics commission, in a clinical study, CT data of 24 children (12 unilateral and bilateral hypoplasias each) taken before and after mandibular distraction osteogenesis were used to get information on the amount of created bone and the grade of ossification of the callus at the time of the distractor removal. The CT data were prepared for computer evaluation using software which had been especially developed for this investigation. The quality of the investigation was influenced by disturbed data acquisition (insufficient sedation, Gantry deviation, different axial cuts). Therefore, the estimation of the real increase of bone was not possible, but all in all an increase of the volume could be seen. Using a grey scale analysis, the grade of new bone ossification was over 90% at the time of distractor removal. In our opinion, these results argue against the use of CT scans for the validation of a mandibular distraction. The estimation of the volume is very imprecise, the grade of ossification of the new bone very constant.

Absorptiometry, Photon↗

PubMed2000

[Diagnostic imaging in cardiac diagnosis].

PURPOSE: Cardiac imaging includes determination of the size and structure of the cardiac chambers, valves, great vessels and the coronary arteries, chamber and valvular function, myocardial perfusion, viability and metabolism. MATERIAL AND METHODS: Chest roentgenography, angiography, echocardiography and nuclear imaging are commonly used but computed tomography and magnetic resonance imaging also offer a promising potential. RESULTS: Coronary angiography is the gold standard in assessing coronary anatomy. Fast CT technologies such as electron-beam and multi-low-CT are promising non-invasive imaging modalities in the assessment of coronary artery disease. With intravascular ultrasound early stages of coronary atherosclerosis can be detected. For the assessment of myocardial perfusion and viability as well as cardiac function, scintigraphic methods are widely accepted. However, MRI methods have also reached a high degree of accuracy. Evaluation of chamber and valvular function is, due to its wide availability, the field of echocardiography. CONCLUSIONS: In clinical routine chest roentgenography, angiography, echocardiography and nuclear imaging are well established. The value of computed tomography and magnetic resonance imaging in the evaluation of coronary artery disease, myocardial perfusion, viability and metabolism is yet to be defined.

Coronary Disease↗

PubMed2000

[Cardiac imaging with rapid, retrospective ECG synchronized multilevel spiral CT].

PURPOSE: In this paper a method for cardiac imaging with fast multi-slice CT and retrospectively ECG-gated spiral acquisition is presented. METHODS: A fast multi-slice CT system with 4 simultaneously acquired slices and 0.5 s rotation time is used (Siemens Somatom VolumeZoom). Continuous spiral data of the entire heart volume is acquired together with the patient's ECG and reconstructed with dedicated spiral algorithms providing 250 ms temporal resolution. Three-dimensional image data sets are built up from overlapping slices that are reconstructed in an arbitrary, user-defined phase of the heart cycle (e.g. diastolic phase). To evaluate the capability of the method for functional imaging complete three-dimensional image volumes are reconstructed from the same spiral data set in different phases of the heart cycle. RESULTS: A spiral data set of the entire heart volume may be acquired within a single breath-hold. Typical scan times for standard examinations with 3 mm slice width are 10-15 s, and for high-resolution CT angiographies of the coronary arteries with 1.25 mm slice width about 30-35 s. Motion-free reconstruction of the heart and coronary arteries with high spatial resolution is possible in the diastolic phase of the heart cycle. Multi-phase reconstructions from the same spiral scan data set are possible, however, motion artifacts in heart phases with fast cardiac motion may not be completely avoided. CONCLUSION: Fast multi-slice spiral CT with retrospectively ECG-gated spiral reconstruction is well suited for three-dimensional and functional imaging of the heart, especially for high-resolution imaging of calcified coronary plaques and CT-angiography of the coronary arteries.

Algorithms↗

PubMed2000

Treatment of arterial hypertension with diuretics, beta- and calcium channel blockers in old patients.

Hypertension increases in prevalence with age. Population based studies suggest that more than 50% of people over the age of 65 years may have chronic hypertension. Hypertension, especially systolic hypertension, is the single most common, powerful, however, treatable risk factor for cardiovascular morbidity and mortality in the elderly. In order to assess the effectiveness of antihypertensive drug therapy among the elderly, with diuretics, beta-blockers and calcium channel blockers, a literature search was performed at the Cochrane Library, Medline and Excerpta medica. The Cochrane Hypertension Group identified 14 randomised controlled trials of at least one year duration with 21,785 elderly subjects where diuretics, beta-blockers or calcium channel blockers were used in the treatment group as first line drugs. In their meta-analysis (including one small trial with a central acting antiadrenergic drug) there was a decrease in total mortality (111 vs 129 deaths) and cardiovascular morbidity and mortality (126 vs 177 events) within the treatment group. The three trials restricted to persons with isolated systolic hypertension indicated beneficial effects in the treatment group with regard to cardiovascular morbidity and mortality (104 vs 157 events). Trial data on adverse effects is limited. In three studies, where adverse effects were reported, no substantial differences between treatment and control groups in measures of physical, cognitive and emotional function were found. Cardiovascular benefits of treatment with low dose diuretics or beta-blockers are cleared for elderly subjects with either diastolic or isolated systolic hypertension. Treatment with a long-acting dihydropyridine calcium channel blocker shows beneficial effects in reducing cardiovascular morbidity and mortality for elderly people with isolated systolic hypertension. Due to inconsistent findings in a subgroup meta-analysis of antihypertensive drug treatment in very old people, the efficacy of antihypertensive treatment in these subjects still remains unclear.

Adrenergic beta-Antagonists↗

PubMed2000

[Pseudoaneurysm after Bentall's procedure in acute aortic dissection type A: diagnosis using electron beam tomography].

Pseudoaneurysms are a rare complication following replacement of the ascending aorta or aorto-coronary bypass surgery. We report a case with replacement of the aorta ascendens, the aortic valve, and venous aorto-coronary bypass grafting, in whom a pseudoaneurysm developed at the site of one proximal bypass anastomosis. For the preoperative diagnosis, an ultrafast-CT (Electron Beam Tomography, EBT) was done, as neither the pseudoaneurysm, nor the venous graft could be visualized by selective coronary angiography.

Adult↗