Creutzfeldt-Jakob disease: serial changes on diffusion-weighted MRI

We present serial changes on diffusion-weighted MRI (DWI) in a patient with Creutzfeldt-Jakob disease (CJD). DWI revealed serial changes of abnormal hyperintense lesions that had become more extensive and conspicuous with progression of neurologic findings, more sensitively than conventional MRI. In the late stage, disappearance of abnormal hyperintense lesions on DWI was observed. DWI proved to be particularly useful for monitoring the progression of CJD.

Autoantibodies against cardiac G-protein-coupled receptors define different populations with cardiomyopathies but not with hypertension

It was previously shown that the second extracellular loop of cardiovascular G-protein-coupled receptors is an antigenic target for pharmacologically active autoantibodies in patients with idiopathic dilated cardiomyopathy. To extend these observations to cover patients with the same disease from different geographical origins or to patients with other cardiac diseases, peptides corresponding to the sequences of the second extracellular loops of the human M2 muscarinic receptors and beta adrenoceptors were used as antigens in an enzyme immunoassay. Sera from patients from Sweden and Japan with idiopathic dilated cardiomyopathy (DCM, n = 32), hypertrophic cardiomyopathy (HCM, n = 23), malignant essential hypertension (MEH, n = 11), malignant secondary hypertension (MSH, n = 10), and sera from healthy blood donors (HBD, n = 49) were tested. Sera from patients with DCM recognized the muscarinic receptor peptide in 38% of cases and the beta 1 adrenoceptor peptide in 31% of cases. In 50% of the positive patients, autoantibodies against both peptides coexisted as shown by competition experiments using both peptides as inhibitors. In HCM patients, there was a lower frequency of autoantibodies but with a higher but not significant predominance against the M2 peptide. No autoantibodies were detected in sera from patients with MEH or MSH. Autoantibodies against the M2 muscarinic receptors, affinity-purified from positive patients, displayed pharmacological activity as demonstrated by changes in the affinity and number of radioligand binding sites. In contrast, antibodies purified from positive HBD had no effect. These results confirm that autoantibodies displaying pharmacological activity against G-protein-coupled cardiovascular receptors are mainly restricted to patients with idiopathic dilated cardiomyopathy and that different autoantibody populations are responsible for the recognition of the different receptors.

Fractional change in apparent diffusion coefficient as an imaging biomarker for predicting treatment response in head and neck cancer treated with chemoradiotherapy

BACKGROUND AND PURPOSE

ADC provides a measure of water molecule diffusion in tissue. The aim of this study was to evaluate whether the fractional change in ADC during therapy can be used as a valid predictive indicator of treatment response in head and neck squamous cell carcinoma treated with chemoradiotherapy.

MATERIALS AND METHODS

Forty patients underwent DWI at pretreatment and 3 weeks after the start of treatment. The pretreatment ADC, fractional change in ADC, tumor regression rate, and other clinical variables were compared with locoregional control and locoregional failure and were analyzed by using logistic regression analysis and receiver operating characteristic analysis. Furthermore, progression-free survival curves divided by the corresponding threshold value were compared by means of the log-rank test.

RESULTS

The fractional change in ADCprimary, the fractional change in ADCnode, primary tumor volume, nodal volume, tumor regression ratenode, N stage, and tumor location revealed significant differences between locoregional failure and locoregional control (P < .05). In univariate analysis, the fractional change in ADCprimary, fractional change in ADCnode, tumor regression ratenode, N stage, and tumor location showed significant association with locoregional control (P < .05). In multivariate analysis, however, only the fractional change in ADCprimary was identified as a significant and independent predictor of locoregional control (P = .04). A threshold fractional change in ADCprimary of 0.24 revealed a sensitivity of 100%, specificity of 78.7%, and overall accuracy of 84.8% for the prediction of locoregional control. Progression-free survival of the 2 groups divided by the fractional change in ADCprimary at 0.24 showed a significant difference (P < .05).

CONCLUSIONS

The results suggest that the fractional change in ADCprimary is a valid imaging biomarker for predicting treatment response in head and neck squamous cell carcinoma treated with chemoradiotherapy.

A comparative study between MR sialography and salivary gland scintigraphy in the diagnosis of Sjögren syndrome

PURPOSE

The purpose of this work was to compare the diagnostic accuracy of MR sialography with that of salivary gland scintigraphy in Sjögren syndrome.

METHOD

One hundred thirty patients clinically suspected of having Sjögren syndrome were examined by MR sialography and salivary gland scintigraphy. A labial gland biopsy was performed in all patients. Imaging findings of MR sialography and salivary gland scintigraphy were compared with the results of labial gland biopsy.

RESULTS

From the results of labial gland biopsy, the diagnosis of Sjögren syndrome was established in 80 patients. Abnormally high T2 signal intensity areas on MR sialography and decreased uptake and delayed excretion of [(99m)Tc]pertechnetate on salivary gland scintigraphy were well seen in patients with Sjögren syndrome. For the diagnosis of Sjögren syndrome, salivary gland scintigraphy showed higher sensitivity than MR sialography. On the other hand, MR sialography showed higher specificity and positive predictive value (PPV) than salivary gland scintigraphy. Overall diagnostic accuracy was 83% for MR sialography and 72% for salivary gland scintigraphy.

CONCLUSION

The high PPV of MR sialography suggests that MR sialography is the preferred imaging modality in patients suspected of having Sjögren syndrome.

Identification of varicella-zoster virus strains by PCR analysis of three repeat elements and a PstI-site-less region

We established a method of identifying varicella-zoster virus (VZV) strains, especially those of the Oka vaccine, in patients with clinical VZV infections. The DNAs of 30 clinically isolated strains and 4 laboratory strains including the Oka vaccine strain and its parent VZV strain, were analyzed by PCR with four sets of primers for the four variable regions, R2, R4, R5, and a region without a PstI site (PS). R4 was unstable in four laboratory VZV strains and was excluded from the study. The other regions were stable in several passages in cell culture. The number of copies in R2 and R5 were distributed from 2 to 13 and from 1 to 3, respectively, in the strains analyzed. The vaccine strain had seven copies in R2 and two copies in R5, and it was PS negative. Among 30 clinical isolates, 3, 23, and 11 strains had the same characteristics as the vaccine strain in R2, R5, and PS, respectively. Therefore, by this method, 97.2% of the isolates were distinguished from the Oka vaccine strain. This strategy will be useful in diagnosing VZV infections induced by the vaccine strain.

Experimental intraocular lens implantation in the rabbit eye and in the mouse peritoneal space. Part I: Cellular components observed on the implanted lens surface

Polymethylmethacrylate and silicone intraocular lenses (IOLs) were implanted in the rabbit eye and in the mouse peritoneal space to study cellular response to the implanted IOL. Animals were sacrificed at various times after implantation. The removed IOLs were properly fixed and stained using Wolter's implant cytology technique. Scanning and transmission electron microscopic studies were performed. Macrophages, lymphocytes, and fibroblast-like cells were the major components identified. Occasional formations of foreign-body giant cells were seen. The responses observed on IOLs implanted in the rabbit eye were generally milder than those observed on IOLs implanted in the mouse peritoneal space.

Assay of ptaquiloside, the carcinogenic principle of bracken, Pteridium aquilinum, by mutagenicity testing in Salmonella typhimurium

The mutagenicity of ptaquiloside, the carcinogenic principle of Pteridium aquilinum, was tested in Salmonella typhimurium TA100 and TA98. Under weakly basic conditions (pH 8.5), ptaquiloside decomposed into a conjugated dienone (considered to be the ultimate form), which was mutagenic in both strains. A novel bioassay, using the pre-incubation method at pH 8.5 with S. typhimurium tester strains was developed for the assay of ptaquiloside extracted from plants. By this bioassay the ptaquiloside content of ferns collected at different localities during various seasons, and in various parts of the plant was determined. The ubiquitous presence of ptaquiloside in fresh plant materials was confirmed. Bracken processed in alkali was found not to contain the carcinogen.

Experimental intraocular lens implantation in the rabbit eye and in the mouse peritoneal space. Part II: Morphological stages of the macrophage on the implanted lens surface

Macrophages appearing on implanted intraocular lenses (IOLs) in the rabbit eye and in the mouse peritoneal space were observed using Wolter's implant cytology staining and scanning and transmission electron microscopy. In response to the implanted IOL, macrophages in the mouse peritoneal space displayed an activated form with marked ruffles on the surface. They were attached to the IOL with a broad base (sessile macrophage). The macrophages metamorphosed gradually to the flat shape of so-called epithelioid cells with many processes. They showed a tendency to fuse together or become more flat by extending the cytoplasmic lamellipodia and finally disappeared, leaving a thin membrane or a fibrous matrix. Phagocytic activity of macrophages and related cells was also observed. However, those observed on the IOL implanted in the rabbit eye showed less surface structure and appeared to adhere weakly to the IOL.

Experimental intraocular lens implantation in the rabbit eye and in the mouse peritoneal space. Part III: Giant cell formation on the implanted lens surface

Among the cell components appearing on an implanted intraocular lens (IOL), the macrophage is the most active participant in the foreign-body response. The morphological stages of the macrophage in the response include not only an activated form and a flat epithelioid cell, but also a giant cell observed in the later stage of the response. The giant cells on the IOLs implanted in the rabbit eye and in the mouse peritoneal space were investigated by means of Wolter's implant cytology staining and scanning and transmission electron microscopic observation. Differences in the two biological environments as the site of IOL implantation are discussed.

Properties of G-protein modulated receptor-adenylyl cyclase system in myocardium of spontaneously hypertensive rats treated with adriamycin

Properties of the receptor--G protein--adenylyl cyclase system were studied in spontaneously hypertensive rats (SHR) and age-matched normotensive Wistar-Kyoto rats (WKY) treated with adriamycin (ADR, 1 mg/kg per week) for 12 weeks. An identical dosing schedule caused a significantly greater decline in body weight gain and a marked elevation of plasma norepinephrine level in SHR than in WKY. A significant increase in the messenger RNA encoding Gi-alpha 2 was found in SHR+ADR group. The activity of the adenylyl cyclase stimulated by guanyliminodiphosphate [Gpp(NH)p] was decreased by 49% in SHR and 73% in SHR+ADR. However, stimulated activities of adenylyl cyclase by both sodium fluoride and forskolin remained unchanged. Functional level of stimulatory G-protein (Gs) as measured by reconstitution assay in sarcolemmal membrane was unaltered among different groups. Furthermore, the density of beta-adrenoceptor was significantly decreased without change of its affinity. Muscarinic receptors exhibited a three-site affinity distribution in SHR+ADR whereas other groups displayed only two-site affinity distribution. These results suggest that SHR exhibited a depressed myocardial adenylyl cyclase signaling system which may not be due to the functional uncoupling of beta-adrenoceptors from Gs but to the increased inhibitory G-protein (Gi) activity as demonstrated by the increased mRNA of Gi-alpha 2, increased inhibition of Gpp(NH)p-mediated adenylyl cyclase and the super high affinity for carbachol of the muscarinic receptors. Decreased beta-adrenoceptor density and functional alteration of Gi might be regarded as the predisposing factors for the increased susceptibility of myocardium of SHR to ADR.

Experimental intraocular lens implantation in the rabbit eye and in the mouse peritoneal space. Part IV: Cell adhesion, fibroblast-like cell, and lymphocytic cluster observed on the implanted lens surface

Transmission and scanning electron microscopy, Wolter's implant cytology staining, and an immunohistochemical method were used to investigate the process of cell adhesion, the origin of fibroblast-like cells, and the nature of lymphocytic clusters that were observed on intraocular lenses (IOLs) experimentally implanted in the rabbit eye and in the mouse peritoneal space. On the IOL implanted in the mouse peritoneal space, pseudopodia extended during cell adhesion showed morphological variety; on the IOL implanted in the rabbit eye, membranous extensions were seen. Many of the fibroblast-like cells exhibited positive staining for macrophagic antigen, indicating a macrophagic origin. The build-up of lymphocytic clusters, as an indicator of immunologic activity, was frequently observed on IOLs implanted in the mouse peritoneal space, particularly on silicone IOLs. However, such clusters were rarely seen on poly(methyl methacrylate) or silicone IOLs implanted in the rabbit eye, suggesting a much reduced immune response to those materials in the eye chamber.

Excellent acceleration of the Diels-Alder reaction by microwave irradiation for the synthesis of new fluorine-substituted ligands of NMDA receptor

A series of 6,11-ethanobenzo[b]quinolizinium derivatives was synthesized through the Diels-Alder reaction between azoniaanthracne and the corresponding 1,1-disubstituted olefin. After a systematic investigation for achieving rapid synthesis, it was found that the reaction is accelerated in polar media such as H2O and trifluoroethanol. In particular, excellent acceleration was effected by microwave irradiation. The new fluorine-substituted ligands thus obtained exhibited potential affinity toward NMDA receptors.

Emotional eating and eating psychopathology in nonclinical groups: a cross-cultural comparison of women in Japan and the United Kingdom

OBJECTIVE

Emotional eating is associated with eating psychopathology among Western populations. It is not known whether the same conclusions hold in non-Western cultures, where norms for emotional expression differ. This study examined whether emotional eating has the same eating psychopathology correlates in different cultures.

METHOD

Three groups of nonclinical women were compared-Japanese living in Japan; Japanese living in the United Kingdom; and British living in the United Kingdom. They completed an Emotional Eating Scale and the Eating Disorders Inventory.

RESULTS

There were different patterns of association between emotional eating and eating attitudes in the three groups. British women showed a strong linkage, Japanese women living in Japan showed no association, and Japanese women in the United Kingdom showed an intermediate pattern.

CONCLUSIONS

Emotional eating may be less of an index of eating psychopathology in non-Western cultures. However, there appears to be an acculturative process, linking the two when one enters a Western culture. This cross-cultural difference may have implications for the targeting of therapies, although this conclusion requires support from further research.

Oxaliplatin-based chemotherapy induces extravasated platelet aggregation in the liver

Oxaliplatin-based chemotherapy plays a central role in the treatment of patients with colorectal liver metastasis (CRLM). This treatment, however, has been associated with hepatic sinusoidal obstruction syndrome (SOS), a clinically important adverse effect characterized by a bluish hue of the liver, splenomegaly and thrombocytopenia, resulting in liver dysfunction. The significant association between the sinusoidal endothelium and platelets has suggested that oxaliplatin-based chemotherapy affects platelets in the liver. This study compared platelet counts in patients who did and did not receive oxaliplatin-based neoadjuvant chemotherapy (NAC). The peripheral blood platelet count was significantly lower in the NAC group (n=17) compared to that in the non-NAC, or control group (n=15) (P<0.05). The spleen index was also higher in the NAC group, although the difference was not significant. However, the spleens of the patients in the NAC group were significantly enlarged following treatment (P<0.01). Immunostaining for the platelet surface marker CD42b (glycoprotein Ib), revealed more platelets in the liver in the NAC compared to the control group, particularly in the centrilobular zone III, adjacent to the hepatic central vein and in contact with hepatocytes (P<0.01). The platelets present in the spaces of Disse, referred to as extravasated platelet aggregation (EPA), secrete a number of growth factors, including transforming growth factor-β, vascular endothelial growth factor-A, plasminogen activator inhibitor-1 and thromboxane A2. In conclusion, EPA may play an important role in the development of hepatic SOS. Moreover, antiplatelet drugs may prevent the onset of SOS and hepatic injury in patients treated with oxaliplatin-based chemotherapy for CRLM.

Comparison of high-resolution contrast-enhanced 3D MRA with digital subtraction angiography in the evaluation of hepatic arterial anatomy

AIM

To evaluate the validity of high-resolution contrast-enhanced three-dimensional magnetic resonance angiography (MRA) in defining hepatic arterial anatomy and to compare this with digital subtraction angiography (DSA).

MATERIALS AND METHODS

MRA and DSA were performed in 30 patients. MRA was performed with breath-hold, gadolinium-enhanced, three-dimensional, fast low-angle shot sequence with a 512 pixel matrix. MRA was compared with DSA in terms of image quality and depiction of hepatic arterial anatomy. The agreement in image quality between MRA and DSA was determined with the kappa statistic.

RESULTS

With respect to image quality, there was excellent or good correlation between MRA and DSA for the common hepatic artery (kappa=0.85), proper hepatic artery (kappa=0.72), gastroduodenal artery (kappa=0.70), left hepatic artery (kappa=0.49), left gastric artery (kappa=0.50), splenic artery (kappa=0.84), and superior mesenteric artery (kappa=0.88). Poor correlation was found for the right hepatic artery (kappa=0.18) and right gastric artery (kappa=0.38). With regard to hepatic arterial anatomy, MRA correlated correctly with DSA in 28 of the 29 cases, i.e. 97% of patients.

CONCLUSION

MRA is a useful technique for the evaluation of the hepatic artery, and for the vast majority of patients, MRA can replace intra-arterial DSA.

MR imaging of subchondral osteonecrosis of the vertebral body after percutaneous laser diskectomy

OBJECTIVE

We describe four cases of subchondral osteonecrosis of the vertebral body that occurred after percutaneous laser diskectomy. Follow-up MR imaging after laser intervention showed abnormal findings in the vertebral body immediately adjacent to the site of diskectomy that are consistent with subchondral osteonecrosis.

CONCLUSION

MR imaging features of this complication include a wedge-shaped low signal intensity on T1-weighted images, high and low signal intensities on T2-weighted images, and a contrast-enhanced area corresponding to high signal intensity on T2-weighted images. Possible causative mechanisms include thermal injury and photoacoustic shock.

Long-term follow up of abdominal aortic aneurysm complicating Kawasaki disease: comparison of the effectiveness of different imaging methods

A 2 month old boy with Kawasaki disease developed the rare complication of abdominal aortic aneurysm (AAA). He was followed up over 7 years by ultrasonography (2D-ECHO) with and without Doppler flow evaluation, angiography and computed tomography. Calcification was noted 33 months after the onset of the disease but the aneurysm did not decrease in size. 2D-ECHO was adequate for evaluating the size of an aneurysm, but did not show thrombus formation or calcification. Doppler flow studies did not show abnormally high blood flow velocities either at the inflow or outlet of aneurysms, which are indicative of stenosis. On the other hand an abdominal aortogram provided information regarding the luminal shape and abnormalities in flow pattern suggestive of thrombus formation. Fluoroscopy cannot demonstrate calcification in the early stages. Computed tomography (CT) was the imaging method of choice for the evaluation of obstructive or calcific changes; an organizing thrombus was clearly demonstrated and early detection of calcification was possible.

The quadrilateral space syndrome

We describe a 21-year-old woman with left shoulder pain increased by desk work. Left subclavian angiography disclosed occlusion of the posterior circumflex humeral artery on abduction and external rotation of the arm, compatible with the previous reports of the quadrilateral space syndrome. This syndrome should be considered in patients with shoulder pain of unknown aetiology.

Characterization of 5,7-dichlorokynurenate-insensitive D-[3H]serine binding to synaptosomal fraction isolated from rat brain tissues

To explore target sites for endogenous D-serine that are different from the glycine site of the N-methyl-D-aspartate (NMDA) type glutamate receptor, we have studied the binding of D-[3H]serine to the synaptosomal P2 fraction prepared from the rat brain and peripheral tissues in the presence of an excess concentration (100 microM) of the glycine site antagonist 5,7-dichlorokynurenate (DCK). Nonspecific binding was defined in the presence of 1 mM unlabeled D-serine. Association, dissociation, and saturation experiments indicated that D-[3H]serine bound rapidly and reversibly to a single population of recognition sites in the cerebellar P2 fraction in the presence of DCK, with a K(D) of 614 nM and a Bmax of 2.07 pmol/mg of protein. D-Serine, L-serine, and glycine produced a total inhibition of the specific DCK-insensitive D-[3H]serine binding to the cerebellum with similar Ki values. Strychnine and 7-chlorokynurenate failed to inhibit the binding at 10 microM. The profiles of displacement of the DCK-insensitive D-[3H]serine binding by various amino acids and glutamate and glycine receptor-related compounds differ from those of any other defined recognition sites. DCK-insensitive D-[3H]serine binding was at high levels in the cerebral cortex and cerebellum but very low in the kidney and liver. The present findings indicate that the DCK-insensitive D-[3H]serine binding site could be a novel candidate for a target for endogenous D-serine in mammalian brains.