[Current topics in glaucoma]

Among the many factors involved in the development of glaucoma, the elevation of intraocular pressure (IOP) is the most important. The treatment of glaucoma aims to lower IOP in order to maintain visual function. New anti-glaucoma drugs, latanoprost and nipradilol, have been shown to effect a reduction in IOP equal to that achieved with the equivalent dosage of timolol, with no adverse systemic side effects. The mechanism of the reduction of IOP by these drugs mainly involves the increase of uveoscleral outflow. The success rate of filtering surgery for glaucoma has been increased by using antimetabolites such as mitomycin C (MMC) and 5-fluorouracil (5-FU). The use of MMC during surgery has resulted in a better outcome than with 5-FU. Normal tension glaucoma (NTG) cases are reported to constitute more than 60% of total glaucoma cases in Japan. NTG is different from primary open-angle glaucoma not only in IOP but also in the pattern of the visual field defect, cupping and peripapillary atrophy of the optic nerve head (ONH). The first choice of treatment for NTG is using drugs for reducing IOP and, if necessary, argon laser trabeculoplasty. In addition to these treatments a drug for increasing the blood circulation in the brain, brovinecamine fumarate, has shown beneficial effects in the treatment of NTG. NTG patients whose visual field can be shown by static perimetry to be deteriorating are indicated for filtering surgery. The results of filtering surgery for NTG have been confirmed that it is more effective than drugs for maintaining the visual field. We have developed an instrument using the laser speckle phenomenon for determining the microcirculation in the eye, as well as in the ONH, noninvasively, quantitatively, and repetitively. With the same instrument, the effects of anti-glaucomadrugs on ocular circulation, especially in the ONH, can also be determined. Timolol has no effect on the circulation in the ONH, but carteolol and betaxlol increase the circulation significantly. The Ca(+2)-blocker, nilvadipine, increases the circulation in the ONH. These findings indicate that the drugs increasing the ONH circulation many be beneficial for the control of glaucoma.

Glucose metabolism in the cortical and subcortical brain structures in multiple system atrophy and Parkinson's disease: a positron emission tomographic study

The brain glucose metabolism was studied by PET with 18F-FDG in 11 patients with multiple system atrophy (MSA) and 12 patients with idiopathic Parkinson's disease (PD). Seven of the 11 MSA patients were diagnosed as having olivopontocerebellar atrophy, two had striatonigral degeneration, while two demonstrated Shy-Drager syndrome. The glucose metabolic rates for each region in the PD patients showed no difference from the normal controls. The frontal, temporal and parietal cortical glucose metabolic rates and the caudate, the putaminal, the cerebellar and the brainstem glucose metabolic rates in the MSA patients decreased significantly from the controls. The atrophy of the cerebellum and the brainstem in the MSA patients were scored by MRI. The cerebellar and brainstem glucose metabolism in the MSA patients decreased as the atrophy score in such regions advanced in each group; however, some patients with no atrophy showed a decreased glucose metabolism. Although the cerebellar and the brainstem glucose metabolism decreased in all MSA patients, such a decrease was not observed in the SND patients. The decrease in the glucose metabolism for the non-cortical regions in the MSA patients seems to be due to a diffuse depletion of the neurons not restricted to the nigrostriatal neurons. Deafferentation to the cerebral cortices seems to result in a decreased cortical metabolism. The differences in the glucose metabolism between MSA and PD as assessed by PET may be caused by the pathophysiological differences between MSA and PD, and such differences therefore appear to be useful when making a differential diagnosis between MSA and PD. The relative sparing of the brainstem and cerebellar glucose metabolism is considered to be a feature of patients with SND.

[Effectiveness of the radioactive strontium (89Sr) chloride agent, SMS.2P for pain palliation in patients with metastatic bone tumor in phase III multicenter clinical trial]

The phase III clinical trial of strontium-89 chloride agent (SMS.2P) was performed in 90 patients with painful bone metastases secondary to prostate (53), breast (18) and other types of cancer (19). Some patients experienced a transient increase in pain or nausea and vomiting. However both symptoms subsided and serious side effects were not observed in any of the patients. As reported, we confirmed some abnormal changes in peripheral blood picture. A decrease in the number of white blood cells and platelets was considered to be partly a result of bone marrow suppression due to 89Sr irradiation. Pain was substantially improved after 89Sr therapy in 58% of the patients and there was some alleviation in 12%. The release from pain was accompanied by an improved quality of life for these patients including sleep patterns and morbidity. Some patients were able to resume their former life styles. Most of the improved patients experienced pain relief from days to one week following 89Sr therapy and in half cases, this remained effective for 2 or 3 months. There were even cases in which the pain relief continued over an observation period of time of clinical study.

V alpha 14+ NK T cells: a novel lymphoid cell lineage with regulatory function

A novel lymphoid lineage, NK T cells, was recently found. The NK T cells are the major population in the periphery comprising 5% of splenic T cells and 40% of bone marrow T cells. They express a unique TCR composed of invariant V alpha 14J alpha 281 and V beta 8.2 together with NK receptor (NKRPI). Surprisingly, the invariant V alpha 14+ TCR is exclusively expressed on NK T cells but not on conventional T cells. As the selective decrease in V alpha 14+ NK T cell population in the periphery is tightly correlated with autoimmune disease development, V alpha 14+ NK T cells control development of autoimmune diseases. We also found that V alpha 14 TCR gene rearrangement and transcripts were detected at an early embryogenesis (d9.5) before the thymus formation. Therefore NK T cells are in the distinct category from conventional T cells. The target of NK T cells is found to be CD1 (class 1b, monomorphic class I MHC-like molecule) present on bone marrow-derived cells and is killed by Fas-FasL interaction or perforin-mediated mechanisms. These results indicate that NK T cells consist of an immunoregulatory system different from defense system in terms of homogeneous repertoire, extrathymic development in early stage of gestation, and their regulatory functional role.

Regulation of bcl-xL expression and Fas susceptibility in mouse B cells by CD40 ligation, surface IgM crosslinking and IL-4

CD40 is one of the key molecules involved in the survival, growth and differentiation of B lymphocytes. In contrast, Fas (Apo-1, CD95) mediates apoptosis of a variety of cell types, including lymphocytes. Recent studies have found that Fas expression on mouse B cells could be strongly induced by CD40 ligation, a helper T cell-derived signal. Here, evidence is provided that CD40 ligation induced two distinct signals: one leading to the upregulation of Fas and the other leading to the enhanced Fas susceptibility. B lymphoma cell lines, CH31 and WEHI279, expressed Fas on cell surfaces, but were resistant to anti-Fas antibody (Ab) induced apoptosis. Treatment with CD40 ligand (CD40L), however, greatly enhanced Fas susceptibility of these cells. Similarly, normal splenic B cells became highly susceptible to Fas-mediated apoptosis following prolonged signaling through CD40. While CD40 ligation enhanced Fas-mediated apoptosis, stimulation with anti-IgM and IL-4 partially protected CD40L-activated B cells from Fas-mediated apoptosis. It was found that bcl-xL gene expression in normal splenic B cells was induced drastically by treatment with anti-IgM and IL-4, but not CD40L. By contrast, the expression of bcl-2 or bax was not significantly affected by these treatments. Moreover, in three of the four B lymphoma cell lines tested, Fas susceptibility correlated with the status of bcl-xL expression. The data suggest that an increase in bcl-xL expression may protect B cells from Fas-mediated apoptosis.

Serum levels of hyaluronic acid indicate the severity of joint symptoms in patients with systemic and polyarticular juvenile rheumatoid arthritis

OBJECTIVE

Elevated serum levels of hyaluronic acid (HA) correlate with joint inflammation in adult rheumatoid arthritis (RA). There are no laboratory indices for specifically assessing joint inflammation. Therefore, serial measurements of HA were assessed as a possible tool for measuring the severity of arthritic symptoms in children with juvenile rheumatoid arthritis (JRA).

METHODS

Serum levels of HA, measured by a sandwich assay method using HA binding protein, were correlated with the severity of joint symptoms and with laboratory test values in 71 patients with JRA, 30 children with other rheumatic diseases, and 138 children without rheumatic disease.

RESULTS

Serum levels of HA showed significant correlation with the severity of joint symptoms, but not with systemic symptoms, in patients with systemic and polyarticular JRA. No other laboratory tests, including C-reactive protein and erythrocyte sedimentation rate, reflected the severity of joint symptoms. This correlation of serum levels of HA with joint symptoms was observed in patients with systemic and polyarticular JRA, but not in pauciarticular JRA, other rheumatic diseases, or nonrheumatic diseases, even when signs of arthritis were present in the latter 3 groups.

CONCLUSION

Serum levels of HA are useful in objectively evaluating arthritic symptoms in patients with systemic and polyarticular JRA, and may have diagnostic value in this disease.

Contrast-enhanced MRI in spinal arteriovenous malformations and fistulae before and after embolisation therapy

MRI was performed in six cases of spinal arteriovenous malformation (AVM) and arteriovenous fistula (AVF) before and after embolisation. Intramedullary and perimedullary AVMs showed marked vascular enhancement after embolisation. This was thought to reflect feeding vessel occlusion and correlated well with a favourable clinical outcome. In dural AVFs, contrast-enhanced studies were essential for the diagnosis, unenhanced images being nonspecific. After embolisation, enhancement of the spinal cord was reduced, although one case with a poor outcome showed persistent enhancement.

Expression of hybrid isomyosins in human skeletal muscle

Myosin of human skeletal muscles was analyzed by means of several electrophoretic techniques. Myosin heavy chain (HC)-IIa-and HC-IIb-based isomyosins were identified by pyrophosphate-polyacrylamide gel electrophoresis (PP-PAGE). The electrophoretic mobilities of these fast-twitch muscle isomyosins differed in the order HC-IIa triplets < HC-IIb triplets. To determine the subunit composition of myosin molecules that function in intact muscle, two-dimensional electrophoresis in which the first and second dimensions were PP-PAGE and sodium dodecyl sulfate-PAGE, respectively, was also performed. Slow-twitch muscle isomyosin contained, in addition to slow-twitch light chain (LC) and HC-I isoforms, appreciable amounts of LC-2f, HC-IIa, and HC-IIb isoforms, and fast-twitch muscle isomyosin consisted of LC-2s and HC-I isoforms as well as fast-twitch LC and HC isoforms. Without consideration of HC- and slow-twitch alkali LC heterodimers, at least 31 possible isomyosins are derived from these findings on the subunit composition of isomyosins in human skeletal muscle.

Asymptomatic colorectal cancer detected by screening

PURPOSE

Colorectal cancer screening has become prevalent. To discuss the efficacy of screening, we studied the characteristic of asymptomatic colorectal cancer detected by screening.

METHODS

This is a retrospective review of patients with colorectal cancer treated at our institution. During the past 20 years, 96 of 1,046 cases of colorectal cancer were asymptomatic and detected by screening. Sixty-one of these cases were detected in the recent five years. The initial screening procedures were fecal occult blood test in 51 cases, sigmoidoscopy or colonoscopy in 18, barium enema in 9, and other tests in 18.

RESULTS

Thirteen lesions (14 percent) were smaller than 1.0 cm and 32 (33 percent) were 1-2 cm in size. There were 34 Tis, 21 T1, and 8 T2 tumors. Of the 55 Tis or T1 lesions, 14 showed nonpolypoid growth (5 flat-elevated, 7 flat-elevated with depression, 1 flat, 1 depressed), and 12 of these were detected on endoscopy. Thirty-four cases were TNM Stage 0, 25 were Stage I, 16 were Stage II, 12 were Stage III, and 9 were Stage IV. Sixty-one percent of those detected by screening were in either Stage 0 or Stage I compared with 16 percent in the symptomatic group. Cumulative five-year disease-free survival rates were 100 percent for both Stage 0 and Stage I, 94 percent for Stage II, and 52 percent for Stage III. Overall cumulative five-year survival rate was 87 percent for those detected by screening, compared with 57 percent in symptomatic patients.

CONCLUSIONS

Asymptomatic cancers detected by screening were at a less advanced stage. In particular, many nonpolypoid early cancers were detected by endoscopic screening.

Essential requirement of an invariant V alpha 14 T cell antigen receptor expression in the development of natural killer T cells

NK1.1+ T [natural killer (NK) T] cells express an invariant T cell antigen receptor alpha chain (TCR alpha) encoded by V alpha 14 and J alpha 281 segments in association with a limited number of V betas, predominantly V beta 8.2. Expression of the invariant V alpha 14/J alpha 281, but not V alpha 1, TCR in transgenic mice lacking endogenous TCR alpha expression blocks the development of conventional T alpha beta cells and leads to the preferential development of V alpha 14 NK T cells, suggesting a prerequisite role of invariant V alpha 14 TCR in NK T cell development. In V beta 8.2 but not B beta 3 transgenic mice, two NK T cells with different CD3 epsilon expressions, CD3 epsilon(dim) and CD3 epsilon(high), can be identified. CD3 epsilon(high) NK T cells express surface V alpha 14/V beta 8 TCR, indicating a mature cell type, whereas CD3 epsilon(dim) NK T cells express V beta 8 without V alpha 14 TCR and no significant CD3 epsilon expression (CD3 epsilon(dim)) on the cell surface. However, the latter are positive for recombination activating gene (RAG-1 and RAG-2) mRNA, which are only expressed in the precursor or immature T cell lineage, and also possess CD3 epsilon mRNA in their cytoplasm, suggesting that CD3 epsilon(dim) NK T cells are the precursor of V alpha 14 NK T cells.

Primary malignant lymphoma in the porta hepatis: a case report

A case of primary lymphoma in the porta hepatis is presented here. Cholangiography, angiography, ultrasonography and computed tomography suggested the presence of a mass in the porta hepatis, but all these failed to demonstrate the tumor clearly. Magnetic resonance imaging was very useful in defining the characteristics of the tumor and in delineating its extent, though it was not specifically diagnostic.

Intra-arterial digital subtraction angiography with extra-large fields using a computed radiography system in evaluating peripheral vascular disease

The authors evaluated the usefulness of intra-arterial digital subtraction angiography (DSA) with extra-large field sizes using a computed radiography (CR) system in evaluating peripheral vascular disease (PVD). Intra-arterial DSA using CR was performed in 55 patients with suspected PVD. A 4 F catheter was advanced into the abdominal aorta via the transbrachial approach and 90 ml of contrast medium was injected during six exposures using a long leg changer mounting a total of 18 imaging plates on six surfaces. Visualization of the superficial femoral and popliteal arteries was judged as diagnostic in all cases. The abdominal aorta, iliac arteries, and subtrifurcation were also visualized in most cases, but visualization was suboptimal in some cases. As a complication, median nerve palsy occurred in one case. This technique is thought to be a useful method for evaluating PVD because of the advantages of a large field of view and wide exposure latitude, in spite of its relatively long processing time.

Breast lesions: correlation of contrast medium enhancement patterns on MR images with histopathologic findings and tumor angiogenesis

PURPOSE

To compare qualitative and quantitative magnetic resonance (MR) mammographic features of breast lesions with histopathologic findings, especially tumor angiogenesis.

MATERIALS AND METHODS

Seventy-three patients (72 women, one man; aged 30-78 years; mean age, 51.0 years) with suspicious breast lesions underwent MR imaging. Noncontrast medium-enhanced localization imaging and then gadolinium-enhanced dynamic fast spoiled gradient-recalled-echo (SPGR) imaging were performed in all patients. In selected patients, subtraction fast SPGR images were obtained. The Pearson and Spearman correlation tests were used to determine the strength of the relationships between enhancement parameters and microvessel determinations.

RESULTS

Time intensity curve type correlated with microvessel density grade (Spearman rank correlation test: r = .90, P < .001). The steepest slope of contrast medium uptake correlated with microvessel counts (Pearson correlation test; r = .83, P < .001). Peripheral enhancement in invasive carcinomas (n = 9) correlated with high peripheral and low central microvessel densities, which were associated with desmoplasia and/or necrosis. Internal septations (n = 2) were seen only in fibroadenomas.

CONCLUSION

The density and distribution of microvessels may play major roles in the determination of the initial rate of contrast medium uptake and the heterogeneity of tumor enhancement.

Radiologically identifiable intratumoral portal vein in intrahepatic cholangiomas: a diagnostic pitfall

BACKGROUND

Although intratumoral patent portal vein (ITPV) is one of the characteristic features of benign hepatic lesions, ITPVs can be demonstrated in malignant tumors. We present the spectrum of MR and CT findings of ITPV identified in intrahepatic cholangiomas with pathological correlations.

METHODS

The ultrasound, CT and/or MRI findings of pathologically-confirmed intrahepatic cholangiomas were reviewed and correlated with surgical specimen or autopsy findings.

RESULTS

Intratumoral patent vessels were radiographically-demonstrated in 5 patients with intrahepatic cholangiomas. All intratumoral vessels were secondary or tertiary order portal vein branches. Some wall thickening was identified on pathological examinations.

CONCLUSION

The radiological demonstration of intratumoral portal vein is not a specific sign of benignity. In the case of a hepatic tumor with a patent portal tract, cholangioma should be considered, as well as benign tumors or lymphoma.

Helical CT imaging of bronchial arteries with curved reformation technique in comparison with selective bronchial arteriography: preliminary report

PURPOSE

Our goal was to evaluate the ability of helical CT to identify and demonstrate the origins and courses of bronchial arteries, using the curved reformation technique, in patients undergoing bronchial arterial interventional procedures.

METHODS

Thin section helical CT was performed on seven patients before bronchial arterial interventional procedures. The curved reformation technique was used to demonstrate the origins and continuous vessel tracing of bronchial arteries and compared with bronchial arteriographic findings.

RESULTS

In all, 16 bronchial arteries were evaluated, 8 on the right and 8 on the left. The origins of 12 bronchial arteries were identified. In the demonstration of tracing vessels, seven right bronchial arteries and three left were classified as excellent or fair.

CONCLUSION

Helical CT imaging with the curved reformation technique is helpful in identifying bronchial arteries, especially on the right, in patients with indications for bronchial arterial interventional procedures.

Adult human chondrocytes cultured in alginate form a matrix similar to native human articular cartilage

The matrix formed by adult human chondrocytes in alginate beads is composed of two compartments: a thin rim of cell-associated matrix that corresponds to the pericellular and territorial matrix of articular cartilage and a more abundant further-removed matrix, the equivalent of the interterritorial matrix in the tissue. On day 30 of culture, the relative and absolute volumes occupied by the cells and each of the two matrix compartments in the beads were nearly identical to those in native articular cartilage. Furthermore, the concentration of aggrecan in the cell-associated matrix was similar to that in adult human articular cartilage and was approximately 40-fold higher than in the further removed matrix compartment. Fluorescence-activated cell sorting revealed that the cell-associated matrix was built on the cell membrane in part via interactions between hyaluronic acid and CD44-like receptors. Approximately 25% of the aggrecan molecules synthesized by the chondrocytes during a 4-h pulse in the presence of [35S]sulfate on day 9 of culture were retained in the cell-associated matrix where they turned over with a half-life (t1/2) = 29 days. Most [35S]aggrecan molecules reached the further removed matrix compartment where they turned over much more slowly (t1/2 > 100 days). These results add support to the contention that aggrecan molecules residing in the pericellular and territorial areas of the adult human articular cartilage matrix are more susceptible to degradation by proteolytic enzymes synthesized by the chondrocytes than those that inhabit the interterritorial areas further removed from the cells.

A comparison of latanoprost and timolol in primary open-angle glaucoma and ocular hypertension. A 12-week study

OBJECTIVE

To evaluate the intraocular pressure (IOP)-reducing effect and the side effects of latanoprost (PhXA41), a new phenyl-substituted prostaglandin F2 alpha-isopropyl ester analogue, in patients with elevated IOP, using timolol maleate as the reference drug.

METHODS

A total of 184 patients with primary open-angle glaucoma or ocular hypertension at 35 medical centers participated in this randomized double-masked study. The patients were randomized to receive either 0.005% latanoprost once daily or 0.5% timolol maleate twice daily, for a period of 12 weeks. Intraocular pressure was measured 24 hours after the administration of timolol, at 2, 4, 8, and 12 weeks of treatment.

RESULTS

Latanoprost reduced IOP at the end of 12 weeks by 6.2 +/- 2.7 mm Hg (mean +/- SD) (26.8%), while timolol reduced IOP by 4.4 +/- 2.3 mm Hg (19.9%). At all visits latanoprost reduced IOP significantly more than timolol did. The main ocular side effects observed in both groups were conjunctival hyperemia and smarting. The main systemic side effect was a reduced pulse rate, which occurred in patients treated with timolol.

CONCLUSIONS

The results of this study demonstrated that 0.005% latanoprost taken once daily is well tolerated and more effective in reducing IOP than 0.5% timolol taken twice daily. Thus, latanoprost may become an important choice for the medical treatment of glaucoma.

Cerebral blood flow and vascular response to hypercapnia in hypertensive patients with leukoaraiosis

Both arteriosclerosis and leukoaraiosis have a close relationship with hypertension, but the relationship between cerebral hemodynamics and leukoaraiosis in hypertensive patients has not been fully examined. To clarify this issue, we measured the regional cerebral blood flow (rCBF) and cerebrovascular response to hypercapnia in hypertensive patients with various degrees of leukoaraiosis. The subjects consisted of 7 normotensive normal controls and 17 hypertensive patients. The hypertensive patients were divided into three groups according to the severity of white matter lesions (leukoaraiosis) on MRI and the presence of dementia, namely, (1) negative or mild leukoaraiosis without dementia, (2) moderate to severe leukoaraiosis without dementia and (3) severe leukoaraiosis with dementia. Both the rCBF and the cerebrovascular response to hypercapnia were measured by the O-15 H2O bolus-injection method and positron emission tomography. The rCBF in hypertensive patients without dementia did not decrease when compared with the normotensive controls, but the rCBF in hypertensive patients with dementia markedly decreased in the cerebral cortices and white matter. On the other hand, the cerebrovascular response to hypercapnia declined with the severity of leukoaraiosis, and it decreased most severely in patients with severe leukoaraiosis and dementia. Our results indicate that the reduction in the cerebral hemodynamic reserve capacity has a close relationship with the severity of leukoaraiosis in hypertensive patients, although the rCBF is maintained in hypertensive patients without dementia, and suggest that arteriosclerotic change reduces cerebrovascular CO2 response and causes a leukoaraiosis in hypertensive patients.

Cerebral venous angiomas associated with hemorrhagic lesions. Their MRI manifestations

Using two 1.5-T magnetic resonance (MR) scanners, 82 venous angiomas (VAs) were imaged. There were 13 (16%) VAs associated with hemorrhagic lesions. Ten of the 13 hemorrhagic lesions were considered hematomas in the subacute or chronic stage, caused by VAs or coexisting cavernous hemangiomas. Two of the 13 were subacute intracerebral hematomas; the remaining one was a sequela of a hemorrhagic venous infarct. After analysis of our data, it was concluded that infratentorial VAs and deeply draining supratentorial VAs in relatively young adults, especially females, are relatively frequently associated with intracerebral hemorrhagic lesions. MR imaging proved useful for diagnosing VAs and associated hemorrhagic lesions.

[HLA class II alleles and leprosy (Hansen's disease) classified by WHO-MDT criteria]

Human leukocyte antigens (HLA) class II alleles were analyzed in Japanese leprosy patients to ascertain whether immunogenetic differences exist among the forms of leprosy in classification of World Health Organization-recommended multidrug therapy (WHO-MDT). The subjects were 86 unrelated Japanese leprosy patients, including 62 multibacillary leprosy (MBL), 24 paucibacillary leprosy (PBL). Controls were 114 unrelated healthy subjects. Genotyping of HLA class II alleles was performed by using the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and PCR-restriction fragment length polymorphism (RFLP) methods. The frequencies of HLA-DRB1* 1501, * 1502 and DRB5* 0101,* 0102 and DQA1* 0102 and DQB1* 0602 were significantly increased in the whole patients (44.2%, 34.9%, 44.2%, 34.9%, 53.4% and 41.9%, respectively) as compared with the control subjects (14.0%, 21.1%, 14.0%, 21.1%, 27.2% and 13.2%, respectively). On the other hand, the frequencies of HLA-DRB1* 0405, * 0803, * 0901 and DQA1* 03 and DQB1* 0401 were significantly decreased in the whole patients (10.5%, 5.8%, 16.3%, 41.9% and 9.3%, respectively) as compared with the control subjects (29.8%, 17.5%, 30.7%, 78.1% and 29.8%, respectively). When MBL and PBL patients were compared, the frequencies of HLA-DRB1* 1501, DRB5* 0101 and DQB1* 0602 were significantly increased in the MBL patients (51.6%, 51.6% and 48.4%, respectively) as compared with the PBL patients (25.0%, respectively). Our results suggest that HLA-DRB1* 1501, DRB5* 0101 and DQB1* 0602 contribute to the susceptibility to the Japanese MBL.

Neuroradiological applications of a new system of stereoscopic biplane digital subtraction angiography

A stereoscopic biplane digital subtraction angiography (DSA) system was developed, capable of obtaining frontal and lateral projections simultaneously during a single injection of contrast medium. This new system combines the advantages of both biplane and stereoscopic single-plane DSA, and permits high-quality neuroangiography.

Hyperperfusion and hypermetabolism in brain radiation necrosis with epileptic activity

We report a case of high uptake of 11C-methionine (MET), 18F-FDG (FDG) and 201Tl-Cl (Tl) in brain radiation necrosis. Twenty-one years previously, the patient had undergone surgery and radiation therapy consisting of 60-Gy for ependymoma in the anterior horn of the right lateral ventricle. The clinical features consisting of frequent seizures of the left face and arm suddenly appeared 2 wk before admission. MRI depicted a Tl and T2-prolonged lesion in the right frontal lobe. Abnormally high uptake in this area demonstrated by MET-PET, FDG-PET, Tl-SPECT or HMPAO-SPECT suggested the presence of a recurrent tumor. A craniotomy was then performed and an intraoperative electrocorticogram showed continuous epileptic spikes in the lesion. The epileptic foci were resected and the histological features of the lesion were consistent with radiation necrosis. After surgery, the seizures disappeared and the postoperative examinations with MET-PET, FDG-PET, Tl-SPECT and HM-PAO-SPECT no longer showed abnormally high uptake. Hypermetabolism and hyperperfusion related to epileptic fits are therefore thought to result in high uptake of MET, FDG and Tl in radiation necrosis.

Anti-tumor-promoting activities of triterpenoids from ferns. I

To search for possible anti-tumor-promoters (cancer chemopreventive agents), we carried out primary screening of 23 triterpenoid hydrocarbons (1-23) isolated from ferns using an in vitro synergistic assay system. Of these triterpenoids, hop-17(21)-ene (2), neohop-13(18)-ene (3), neohop-12-ene (4), taraxerane (17), multiflor-9(11)-ene (18), multiflor-8-ene (19), glutin-5(10)-ene (21) and taraxastane (23) exhibited remarkable inhibitory effects on Epstein-Barr virus (EBV) activation induced by the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA). Further, compounds 2 and 3 exhibited remarkable anti-tumorpromoting effects on mouse skin tumor promotion in an in vivo two-stage carcinogenesis test using 7,12-dimethybenz[a]anthracene (DMBA) as an initiator and TPA as a promoter.

The usefulness of FDG positron emission tomography for the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer: a comparative study with X-ray computed tomography

We evaluated the usefulness of fluorine-18-fluoro-2-deoxy-d-glucose positron emission tomography (FDG PET) in the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer and then compared the findings with the results of X-ray CT by region based on the histological diagnoses. We examined 29 patients with non-small cell lung cancer. One hundred and thirty-two mediastinal lymph nodes were surgically removed and the histological diagnoses were confirmed. FDG PET images, including 146 mediastinal regions, were visually analysed and the mediastinal lymph nodes were scored as positive when the FDG uptake was higher than that in the other mediastinal structures. On the X-ray CT scans, any mediastinal lymph nodes with a diameter of 10 mm or larger were scored as positive. All three examinations were successfully performed on 71 regions. For FDG PET, we found a sensitivity of 76%, a specificity of 98% and an accuracy of 93%. On the other hand, for X-ray CT a sensitivity of 65%, a specificity of 87% and an accuracy of 82% were observed. A significant difference was observed in respect of both specificity and accuracy (P<0.05). Based on the above findings, FDG PET is suggested to be superior to X-ray CT when used for the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer.

[Evaluation of the usefulness of 111In-DTPA-IgG scintigraphy for the detection of focal inflammatory lesions]

We evaluated the usefulness of 111In-DTPA-IgG scintigraphy for the detection of focal inflammatory lesions. We examined 9 patients with focal inflammatory lesions that had been diagnosed based on the findings of various types of laboratory data and other imaging modalities. Scanning was performed at 6, 24, 36 and 48 hours after the administration of 80 MBq of 111In-DTPA-IgG. The sensitivity was 78%. A good diagnostic ability was observed by the scintigraphy findings at 24 hours. In conclusion, 111In-DTPA-IgG scintigraphy at 24 hours is thus considered to be useful for detecting focal inflammatory lesions.