Selective release of miRNAs via extracellular vesicles is associated with house-dust mite allergen-induced airway inflammation

BACKGROUND

MicroRNAs (miRNAs) may facilitate cell-to-cell communication via extracellular vesicles (EVs). The biological roles of miRNAs in EVs on allergic airway inflammation are unclear.

METHODS

Airway-secreted EVs (AEVs) were isolated from bronchoalveolar lavage fluid (BALF) of control and house-dust mite (HDM) allergen-exposed HDM-sensitized mice. The expression of miRNAs in AEVs or miRNAs and mRNAs in lung tissue was analysed using miRNA microarray.

RESULTS

The amount of AEV increased 8.9-fold in BALF from HDM-exposed mice compared with that from sham-control mice. HDM exposure resulted in significant changes in the expression of 139 miRNAs in EVs and 175 miRNAs in lung tissues, with 54 miRNAs being common in both samples. Expression changes of these 54 miRNAs between miRNAs in AEVs and lung tissues after HDM exposure were inversely correlated. Computational analysis revealed that 31 genes, including IL-13 and IL-5Ra, are putative targets of the miRNAs up-regulated in AEVs but down-regulated in lung tissues after HDM exposure. The amount of AEV in BALF after HDM exposure was diminished by treatment with the sphingomyelinase inhibitor GW4869. The treatment with GW4869 also decreased Th2 cytokines and eosinophil counts in BALFs and reduced eosinophil accumulation in airway walls and mucosa.

CONCLUSION

These results indicate that selective sorting of miRNA including Th2 inhibitory miRNAs into AEVs and increase release to the airway after HDM exposure would be involved in the pathogenesis of allergic airway inflammation.

Pulmonary CD103(+) dendritic cells prime Th2 responses to inhaled allergens

Allergic asthma stems largely from the actions of T helper 2 (Th2) cells, but the pathways that initiate Th2 responses to inhaled allergens are not fully understood. In the lung, there are two major subsets of dendritic cells (DCs), displaying CD11b or CD103. We found that after taking up inhaled ovalbumin in vivo, purified CD103(+) DCs from the lung or lung-draining lymph nodes primed Th2 differentiation ex vivo. Th2 induction by CD103(+) DCs was also seen when cockroach or house dust mite allergens were used. In contrast, CD11b(hi) DCs primed Th1 differentiation. Moreover, mice lacking CD103(+) DCs displayed diminished Th2 priming to various inhaled allergens and did not develop asthma-like responses following subsequent allergen challenge. Low-level antigen presentation by CD103(+) DCs was necessary, but not sufficient for Th2 priming. Together, these findings show that CD103(+) DCs have a significant role in priming Th2 responses to inhaled allergens.

Effect of radiation monitoring method and formula differences on estimated physician dose during percutaneous coronary intervention

BACKGROUND

Currently, one or two dosimeters are used to monitor radiation exposure in most cardiac laboratories. In addition, several different formulas are used to convert exposure data into an effective dose (ED).

PURPOSE

To clarify the effect of monitoring methods and formula selection on the estimated ED for physicians during percutaneous coronary interventions (PCIs).

MATERIAL AND METHODS

The ED of physicians during cardiac catheterization was determined using an optically stimulated luminescence dosimeter (Luxel badge). Two Luxel badges were worn: one beneath a personal lead apron (0.35-mm lead equivalent) at the chest and one outside of the apron at the neck.

RESULTS

The difference in the average ED of seven physicians was approximately fivefold (range 1.13-5.43 mSv/year) using the six different formulas in the clinical evaluation. The estimated physician ED differed markedly according to both the monitoring method and formula selected.

CONCLUSION

ED estimation is dependent on both the monitoring method and the formula used. Therefore, it is important that comparisons among laboratories are based on the same monitoring method and same formula for calculating the ED.

Bakery flour dust exposure causes non-allergic inflammation and enhances allergic airway inflammation in mice

BACKGROUND

Baker's asthma is one of the most commonly reported occupational lung diseases in countries where fresh bread is baked daily in large quantities, and is characterized by rhinitis, bronchial hyperresponsiveness, and reversible airflow obstruction. Epidemiological studies have identified pre-existing atopy as an important risk factor for developing baker's asthma, yet the aetiology and pathogenesis of baker's asthma remain poorly understood.

OBJECTIVE

We sought to develop a mouse model of baker's asthma that could be used to characterize the development and progression of baker's asthma.

METHODS

We were unable to sensitize mice to bakery flour dust or flour dust extract. We assessed total inflammatory cells, cellular differential, total serum IgE and the pro-inflammatory cytokine response to oropharyngeally instilled bakery flour dust or flour dust extract by itself or in the context of ovalbumin (OVA) sensitization and challenge.

RESULTS

Both bakery flour dust and flour dust extract consistently elicited a neutrophilic inflammation in a Toll-like receptor 4-independent manner; suggesting that endotoxin is not playing a role in the inflammatory response to flour dust. Moreover, bakery flour dust and dust extract significantly enhance the inflammatory response in OVA-sensitized and challenged mice.

CONCLUSIONS

Bakery flour dust and flour dust extract are strongly pro-inflammatory and can cause non-allergic airway inflammation and can enhance allergen-mediated airway inflammation.

Role of mitogen-activated protein kinases in influenza virus induction of prostaglandin E2 from arachidonic acid in bronchial epithelial cells

BACKGROUND

Influenza virus (IV) infection causes airway inflammation; however, it has not been determined whether IV infection could catabolize arachidonic acid cascade in airway epithelial cells. In addition, the responsible intracellular signalling molecules that catabolize arachidonic acid cascade have not been determined.

OBJECTIVE

In the present study, to clarify these issues, we examined the cyclooxygenase (COX) expression, cytosolic phospholipase A2 (cPLA2) phosphorylation and prostaglandin E2 (PGE2) release in human bronchial epithelial cells (BEC) upon IV infection, and the role of mitogen-activated protein kinase (MAPK) including extracellular signal-regulated kinase (ERK), p38 MAPK and c-Jun-NH2-terminal kinase (JNK) in catabolizing arachidonic acid cascade in BEC.

METHODS

COX-2 expression, phosphorylation of cPLA2 and phosphorylation of ERK, JNK and p38 MAPK were determined by Western blot. The concentrations of PGE2 were determined by ELISA. PD 98059 as a specific inhibitor of MAPK kinase-1 (MEK-1), an up-stream kinase of ERK, SB 203580 as a specific inhibitor of p38 MAPK and CEP-11004 as a specific inhibitor of JNK cascade were used to investigate the role of ERK, p38 MAPK and JNK in catabolizing arachidonic acid cascade in BEC.

RESULTS

The results showed that (1) IV infection increases COX-2 expression, cPLA2 phosphorylation and PGE2 release, (2) ERK, p38 MAPK and JNK were phosphorylated, (3) CEP-11004 and PD 98059 predominantly attenuated COX-2 expression and cPLA2 phosphorylation, respectively, (4) SB 203580 did not remarkably affect COX-2 expression and cPLA2 phosphorylation, and (5) each inhibitor dose-dependently attenuated PGE2 release by various extents.

CONCLUSION

These results indicate that IV infection activates three distinct MAPKs, ERK, p38 MAPK and JNK, to participate to various extents in the induction of PGE2 synthesis from arachidonic acid in BEC.

Elevated serum leptin concentrations in women with components of multiple risk factor clustering syndrome

This cross sectional study was undertaken to determine whether serum leptin levels were associated with multiple risk factor (MRF) clustering syndrome. We examined the relationship between serum leptin concentrations and blood pressure (BP), serum lipids levels, calculated insulin resistance (HOMA-ratio) and adiposity among 581 Japanese adult women. The serum leptin was increased in female subjects with systolic (> or =160 mmHg) and diastolic > or =90 mmHg) hypertension compared with the normotensive females (mean+/-SE; 9.3+/-0.5 vs 7.7+/-0.3; 10.2+/-0.6 vs 7.1+/-0.3 ng/ml, both p<0.001). Serum leptin was elevated in those with hyper-cholesterolemia (C; > or =220 mg/dl) and triglyceridemia (TG; > or =150 mg/dl) compared with the normolipidemia (9.4+/-0.4 vs 7.8+/-0.3; 11.7+/-0.6 vs 7.5+/-0.2 ng/ml, both p <0.001). Serum leptin was also elevated in those with adiposity (BMI > or =26.4 kg/m2) and insulin resistance (HOMA-ratio > or =2.5) compared with the normal females (14.8+/-0.7 vs 5.2+/-0.2; 11.3+/-1.1 vs 7.1+/-0.4ng/ml, both p<0.001). Even after adjusting for BMI or percent body fat mass (BFM), leptin levels remained to be elevated significantly in all these diseases. There was a positive correlation between serum leptin and systolic, diastolic BP, TC, TG, BMI, BFM, IRI and HOMA-ratio (r=0.12, p=0.005; r=0.24, p<0.0001; r=0.19, p<0.0001; r=0.35, p<0.0001; r=0.72, p<0.0001; r=0.73, p<0.0001; r=0.47, p< 0.0001; r=0.44, p<0.0001), and a negative correlation with HDL-C levels (r= -0.20, p< 0.0001). These correlations were also observed in leptin levels after adjusting for the BMI or BFM. Multiple regression analysis showed that BFM, HOMA-ratio and TG were significant determinants of leptin concentration before (t=12.6, p<0.0001; t=3.33, p=0.001; t=3.22, p=0.001) and after adjusting for BMI or BFM. These results suggest that because serum leptin levels were elevated in components of MRF clustering syndrome, leptin may have a pathophysiological role in MRF clustering syndrome.

Diagnostic value of 201Tl-single-photon emission computerized tomography studies in cases of posterior fossa hemangioblastomas

OBJECT

The 201Tl uptake index was evaluated for its usefulness in formulating a diagnosis of hemangioblastoma. Thallium-201-single-photon emission computerized tomography (SPECT) studies were performed in nine patients harboring hemangioblastomas in the posterior fossa and in five patients (six lesions) with gliomas in the posterior fossa.

METHODS

The 201Tl uptake index was defined as the ratio of mean counts of isotope per pixel in the tumor to mean counts of isotope per pixel in the homologous region of the healthy brain. The 201Tl uptake indices of the early image (TlE) and that of the delayed image (TlD) were calculated. The isotope retention index (RI) was calculated as (TlE - TlD)/TlE. The TlE was 2.7 +/- 0.7 in hemangioblastomas and 2.9 +/- 1.7 in gliomas (mean +/- standard deviation). The TlD was 1.5 +/- 0.4 in hemangioblastomas and 2.4 +/- 1.6 in gliomas. There were no significant differences between hemangioblastomas and gliomas when TlEs and TlDs were compared. The isotope RI was 0.43 +/- 0.07 in hemangioblastomas and 0.15 +/- 0.1 in gliomas, showing a significantly higher RI in hemangioblastomas compared with gliomas (p < 0.01).

CONCLUSIONS

Thallium-201 washout is significantly faster in hemangioblastomas. Hemangioblastoma is biologically benign, but contains a rich capillary network that forms a hypervascular tumor bed. Variations in its appearance on magnetic resonance images may cause difficulties in the differential diagnosis of hemangioblastoma. Thallium-201 SPECT studies can be used to distinguish hemangioblastomas from gliomas in the posterior fossa.

Cine viewing of abdominal CT

A few studies have been reported that CT cine viewing on the CRT is superior to film-based viewing of CT images (Seltzer et al., Radiology 197 (1994) 119; Bonaldi et al., Am. J. Roentgenol. 170 (1998) 373; Tillich et al., Am. J. Roentgenol. 169 (1997) 1611). The purpose of our study is to know how to use cine viewing of abdominal CT. Thirty CT studies on the abdomen with both precontrast and postcontrast images were examined. The suitable rate of cine viewing ranged from 1 to 6 frames per second according to the size, the contrast and the complexity of the anatomical structures, and the slice thickness. For small or complex structures, checking each image might be required to know the full detail of them. Positional sorting among multiphase images, which is followed by consecutive display of a precontrast image, postcontrast early and late phase images at one position and so on, is useful to see the dynamic pattern of enhancement of the anatomical structures. However, there was no significant difference between cine viewing and film-based viewing concerning both the detectability of the anatomical structures and the conspicuity of enhancement of the liver and the pancreas, so that cine viewing might be an alternative to film-based viewing for CT diagnosis of the abdomen.

IL-4 and IL-13 induce myofibroblastic phenotype of human lung fibroblasts through c-Jun NH2-terminal kinase-dependent pathway

BACKGROUND

Myofibroblasts play a role in the airway remodeling response of bronchial asthma. IL-4 and IL-13 are possibly involved in the airway remodeling response by inducing extracellular matrix production by fibroblasts. However, the roles of these cytokines in inducing the phenotypic modulation of human lung fibroblasts (HLFs) to myofibroblasts and the intracellular signal have not been determined.

OBJECTIVE

We examined the effect of IL-4 and IL-13 on inducing the phenotypic modulation of HLFs to myofibroblasts characterized by alpha-smooth muscle actin and examined the role of the mitogen-activated protein (MAP) kinase superfamily in inducing the myofibroblastic phenotype of the HLF to clarify these issues.

METHODS

Phosphorylation and activities of c-Jun NH(2)-terminal kinase (JNK), p38 MAP kinase, and extracellular signal-regulated kinase (Erk) were examined by using Western blotting and in vitro kinase assay. Expression of alpha-smooth muscle actin in IL-4- and IL-13-stimulated HLFs was analyzed by means of Western blotting.

RESULTS

The results showed that (1) IL-4 and IL-13 increased alpha-smooth muscle actin expression in a dose- and time-dependent manner; (2) IL-4 and IL-13 induced increases in JNK and Erk phosphorylation and activity but not p38 MAP kinase activity; (3) CEP-1347 and PD 98059 attenuated IL-4- and IL13-induced JNK and Erk activity, respectively; and (4) CEP-1347, but not PD 98059, attenuated IL-4- and IL-13-induced alpha-smooth muscle actin expression.

CONCLUSION

These results indicate that IL-4 and IL-13 are capable of inducing the phenotypic modulation of HLFs to myofibroblasts, and JNK, but not p38 MAP kinase and Erk, regulates IL-4- and IL-13-induced phenotypic modulation of HLFs to myofibroblasts.

Transforming growth Factor-beta1 induces phenotypic modulation of human lung fibroblasts to myofibroblast through a c-Jun-NH2-terminal kinase-dependent pathway

Myofibroblasts play an important role in the fibrogenic process of pulmonary fibrosis. Transforming growth factor (TGF)-beta is well known to induce the phenotypic modulation of fibroblasts to myofibroblasts; however, the intracellular signal regulating induction of the myofibroblastic phenotype of human lung fibroblasts (HLF) has not been determined. In the present study, we examined the role of the mitogen-activated protein kinase (MAPK) superfamily in inducing the phenotypic modulation of HLF to myofibroblasts characterized by alpha-smooth-muscle actin expression, in order to clarify this issue. The results showed that: (1) TGF-beta1 caused the phenotypic modulation of HLF to myofibroblasts in a dose- and a time-dependent manner; (2) TGF-beta1 induced increases in c-Jun-NH2- terminal kinase (JNK), p38 MAPK, and extracellular signal-regulated kinase (Erk) phosphorylation and activity; (3) the inhibitors CEP-1347, SB 203580, and PD 98059 attenuated TGF-beta1-induced JNK, p38 MAPK, and Erk activity, respectively; and (4) CEP-1347, but not SB 203580 or PD 98059, attenuated the TGF-beta1-induced phenotypic modulation of HLF to myofibroblasts in a dose-dependent manner. These results indicate that TGF-beta1 is capable of inducing the myofibroblastic phenotype of HLF, and that JNK regulates the phenotypic modulation of TGF-beta1-stimulated HLF to myofibroblasts.

Inhalant corticosteroids inhibit hyperosmolarity-induced, and cooling and rewarming-induced interleukin-8 and RANTES production by human bronchial epithelial cells

Inhaled corticosteroids are widely used for the treatment of bronchial asthma, and a long-term treatment with inhaled corticosteroids is effective in preventing exercise-induced bronchoconstriction (EIB). We have previously shown that hyperosmolarity, and cooling and rewarming induced interleukin-8 (IL-8) expression in human bronchial epithelial cells (BEC). However, the effect of inhalant corticosteroids on hyperosmolarity-induced, and cooling and rewarming-induced IL-8 and RANTES production has not been determined. To clarify these issues, we examined the effect of inhalant corticosteroids, beclomethasone dipropionate (BDP), and budesonide (BUD) on hyperosmolarity-induced, and cooling and rewarming-induced IL-8 and RANTES production. The results showed that BDP and BUD inhibited hyperosmolarity-induced, and cooling and rewarming-induced IL-8 and RANTES production. Because our previous studies have shown that p38 mitogen-activated protein (MAP) kinase and c-Jun-NH(2)-terminal kinase (JNK) regulate hyperosmolarity-induced, and cooling and rewarming-induced IL-8 and RANTES production, we examined the effect of BDP and BUD on p38 MAP kinase and JNK activation. The results showed that BDP and BUD did not inhibit hyperosmolarity-induced and cooling-induced p38 MAP kinase and JNK activation. These results indicated that inhalant corticosteroids inhibited hyperosmolarity-, and cooling and rewarming-induced IL-8 and RANTES production; however, the mechanism of inhaled corticosteroid-mediated inhibition of hyperosmolarity-induced, and cooling and rewarming- induced cytokine production remains to be clarified.

[Correlation of pulmonary perfusion volume analysis with pulmonary function in emphysema]

Pulmonary perfusion single photon emission tomography with 99mTc MAA was performed on 13 pulmonary emphysema patients and 6 controls. We calculated perfusion volume with lower 10%, 20%, 30%, 40% and 50% of the highest counts/boxels in the lung cut-off. And perfusion index (PI) was defined as follows; PI = ((A% cut-off volume) - (B% cut-off volume))/(A% cut-off volume); A and B take 10 to 50, A < B. The correlation of each PI and pulmonary function test results (FEV1, FEV1%, VC, VC%, FVC, FVC%, PaO2 and PaCO2) was examined. There were significant correlation between every PI and FEV1 or FEV1% (p < 0.05), and any PI had no significant correlation with other functional results. When A = 10 and B = 40, the PI showed the best correlation with FEV1 (r = 0.680) and FEV1% (r = 0.830). And the PI showed an increasing tendency along with the rise of the emphysema severity. The PI may have the clinical utility of the evaluation of pulmonary function. Moreover, we showed the lung CT painted the area where the uptake counts/boxels was more than 10% and less than 40% of the highest counts/boxels. This makes it easy to understand the severe emphysematous area.

Selective inhibitor of p38 mitogen-activated protein kinase inhibits lipopolysaccharide-induced interleukin-8 expression in human pulmonary vascular endothelial cells

Adult respiratory distress syndrome (ARDS) characterized by permeability edema is observed in severe insults such as bacteremia sepsis. Interleukin (IL)-8, which chemoattracts and activates neutrophils, has been suggested to play an important role in the production of ARDS. Therefore, the inhibition of IL-8 production is an important strategy for the treatment of ARDS. Recent studies have revealed the role of p38 mitogen-activated protein (MAP) kinase in cytokine expression and the inhibition by a selective inhibitor of p38 MAP kinase activity of cytokine expression in a variety of cell types. However, little is known about the role of p38 MAP kinase in lipopolysaccharide (LPS)-induced IL-8 expression in pulmonary vascular endothelial cells and the effect of a selective p38 MAP kinase inhibitor on it. In the present study, we therefore attempted to clarify these issues. The results showed that LPS induced p38 MAP kinase phosphorylation and activity, and SB 203580 as a selective inhibitor of p38 MAP kinase activity inhibited p38 MAP kinase activity and IL-8 expression in LPS-stimulated pulmonary vascular endothelial cells. These results indicate that p38 MAP kinase regulates LPS-induced IL-8 expression in pulmonary vascular endothelial cells. Although it is currently not known whether SB 203580 is capable of producing beneficial effects on ARDS, a strategy of inhibiting p38 MAP kinase activity by a selective p38 MAP kinase inhibitor may apply to the therapy for ARDS.

Long-term right ventricular volume overload increases myocardial fluorodeoxyglucose uptake in the interventricular septum in patients with atrial septal defect

BACKGROUND

Several studies have shown that long-term right ventricular (RV) overload in animal models alters myocardial energy substrate metabolism. However, whether long-term RV volume overload alters this metabolism in the human is unclear.

METHODS AND RESULTS

We performed positron emission tomography with [(18)F]fluorodeoxyglucose (FDG) and single-photon emission tomography (SPECT) with [(201)Tl]TlCl (Tl) and [(123)I]15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) in 11 patients with atrial septal defect (ASD) and 11 control subjects. In the FDG study, we calculated myocardial metabolic rate of glucose (MMR) in interventricular septum (IVS) and left ventricular (LV) free wall. MMR was significantly increased in IVS compared with LV free wall in the ASD patients (420+/-35 versus 333+/-32 mol x kg(-1) x min(-1); P<0.05) but not in the control group (347+/-27 versus 357+/-25 mol x kg(-1) x min(-1)). In both ASD and control groups, SPECT count was not significantly different between IVS and LV free wall in Tl (ASD, 160+/-11 versus 177+/-12; control, 141+/-12 versus 157+/-14 counts per 15 minutes) and BMIPP studies (ASD, 203+/-14 versus 212+/-18; control, 162+/-16 versus 176+/-16 counts per 15 minutes). MMR in the IVS/LV free wall ratio in the ASD group significantly correlated with indices related to RV volume overload.

CONCLUSIONS

Given the assumption that long-term RV volume overload did not affect the lumped constant, the present study suggests that, unlike myocardial perfusion or fatty acid analogue uptake, myocardial glucose utilization in IVS relative to LV free wall is increased in relation to long-term RV volume overload in patients with ASD.

PAF-induced RANTES production by human airway smooth muscle cells requires both p38 MAP kinase and Erk

Airway smooth muscle (ASM) cells, which have been regarded as having contractile properties in response to contractile inflammatory mediators, may also participate in airway inflammatory response by expressing various cytokines, including RANTES. However, the intracellular signal that regulates cytokine expression in ASM cells has not been determined. In the present study, we examined the role of p38 mitogen-activated protein (MAP) kinase and extracellular signal-regulated kinase (Erk) in RANTES production by ASM cells stimulated by platelet-activating factor (PAF) and tumor necrosis factor (TNF)-alpha. The results showed that PAF induced the threonine and tyrosine phosphorylation of p38 MAP kinase and Erk, and p38 MAP kinase and Erk activity. SB 203580 and PD 98059 almost completely inhibited p38 MAP kinase and Erk activity, respectively. SB 203580 and PD 98059 partially inhibited and acted additively to inhibit PAF-induced RANTES production. PAF also induced c-Jun-NH(2)-terminal kinase ( JNK) phosphorylation. TNF-alpha induced p38 MAP kinase and Erk phosphorylation, but neither SB 203580 nor PD 98059 inhibited RANTES production. These results indicate that both p38 MAP kinase and Erk involve RANTES production by ASM cells stimulated with PAF, but not TNF-alpha, and that the role of p38 MAP kinase and Erk in RANTES production by ASM cells appears to be stimulus-dependent.

Grepafloxacin inhibits tumor necrosis factor-alpha-induced interleukin-8 expression in human airway epithelial cells

We examined the effect of grepafloxacin (GPFX), a new fluoroquinolone antimicrobial agent, on interleukin-8 (IL-8) expression in tumor necrosis factor-alpha (TNF-alpha)-stimulated human airway epithelial cells (AEC). GPFX inhibited IL-8 protein production as well as mRNA expression in a concentration-dependent manner (2.5 - 25 micro g/ml), but the inhibition of IL-8 expression by corresponding concentrations of GPFX to serum and airway lining fluids was not complete. We discuss the modulatory effect of GPFX on IL-8 production in the context of its efficacy on controlling chronic airway inflammatory diseases.

p38 MAP kinase regulates TNF alpha-, IL-1 alpha- and PAF-induced RANTES and GM-CSF production by human bronchial epithelial cells

BACKGROUND

RANTES and granulocyte macrophage-colony stimulating factor (GM-CSF) play an important role in the production of allergic inflammation of the airway through their chemotactic activity for eosinophils. Recent studies have indicated that p38 mitogen-activated protein (MAP) kinase regulates cytokine expression in various cells; however, the role of p38 MAP kinase in RANTES and GM-CSF production in human bronchial epithelial cells (BECs) has not yet been determined.

OBJECTIVE

In the present study, we examined serine phosphorylation of MKK3 and MKK6 which is the upstream regulator of p38 MAP kinase and p38 MAP kinase activation in tumour necrosis factor (TNF)-alpha, interleukin (IL)-1 alpha and platelet-activating factor (PAF)-stimulated BECs and the effect of SB 203580 as the specific inhibitor for p38 MAP kinase activity on RANTES and GM-CSF expression in order to clarify the intracellular signal regulating RANTES and GM-CSF production by human BECs.

RESULTS

The results showed that TNF alpha, IL-1 alpha and PAF induced serine phosphorylation of MKK3 and MKK6, and p38 MAP kinase activation in BECs. SB 203580 inhibited p38 MAP kinase activity and RANTES and GM-CSF production by TNF alpha-, IL-1 alpha- or PAF-stimulated human BECs.

CONCLUSIONS

These results indicate that p38 MAP kinase plays an important role in TNF alpha-, IL-1 alpha- or PAF-activated signalling pathway which regulates RANTES and GM-CSF production by BECs and that the specific inhibitor for p38 MAP kinase activity might be useful for the treatment of allergic inflammation of the airway.

The perfusion defect seen with SPECT in West syndrome is not correlated with seizure prognosis or developmental outcome

We used interictal single photon emission computed tomography (SPECT) on 40 patients with West syndrome to determine whether cortical perfusion abnormalities are closely related to the development of West syndrome and whether they are correlated with the long-term seizure prognosis or the developmental outcome. Localized cortical perfusion abnormalities were seen in 24 patients (60%), while 15 patients (38%) were classified as normal. The remaining patient showed hyperperfusion of the basal ganglia bilaterally. Of 24 patients with localized perfusion abnormalities, unifocal cortical hypoperfusion was present in 11, multifocal hypoperfusion in 10, multiple cortical hypo- and hyperperfusion in one, hyperperfusion of the bilateral frontal cortices and brain stem in one, and focal hyperperfusion in the residual frontal cortex in one. For statistical analysis, we focused on 26 patients (cryptogenic; 10, symptomatic; 16), who were followed for more than 2 years after the onset of tonic spasms (mean 5.0 years). The results showed that focal cortical perfusion abnormalities were not correlated with the long-term seizure prognosis, the developmental outcome, or the response to ACTH therapy. In agreement with previous reports, the results of interictal SPECT suggested that focal cortical lesions play an important role in the development of West syndrome. However, statistical analysis showed that the existence of cortical dysfunction as defined by SPECT did not predict the seizure prognosis or the developmental outcome.

[Compartment analysis of 123I-iomazenil brain SPECT in patients with moyamoya disease]

We investigated 11 patients with moyamoya disease about 123I-Iomazenil kinetics in the brain using three-compartment, two-parameter model. The transition rate constant (K1) from the blood to the brain and the binding potential (BP) of the benzodiazepine to the receptors were calculated for every ROI (right and left side of cerebellum, frontal lobe, parietal lobe, occipital lobe and temporal lobe; 10 ROIs a case). The K1 value correlated with BP value significantly, but not so closely (r = 0.639). And there is no significant difference in BP value among low-K1 group (mean (of K1) -S.D. < or = K1 < or = mean) and high-K1 group (mean < K1 < or = mean + S.D.). This means that CBF and BP do not correlate closely in the average Moyamoya disease patients. And we showed a case with IMP/IMZ discrepancy. The nerve cell in the hypoperfused area which has almost normal BP value is ischemic but viable. IMZ-SPECT presents an important information about the viability of the hypoperfused area in Moyamoya disease patients' brain.

[Elastase anti-elastase imbalance in the pathogenesis of COPD]

Elastase anti-elastase imbalance theory is most important in the pathogenesis of COPD (pulmonary emphysema). Proteolytic activity of neutrophil elastase (NE) plays an important role because of the detachment of cells through proteolysis of extracellular matrix. In addition to proteolytic activity of NE, NE-induced activation of intracellular signaling (MAPK(Erk), Rho and MLCK) participates in NE-induced morphological changes in airway epithelial cells.

[Comparison of 201Tl-SPECT and MRI using Gd-DTPA for glioma]

201Tl-SPECT was performed in 25 patients with a pathological diagnosis of glioma. The lesion-to-normal (L/N) ratio of the glioblastoma group (n = 7) was found to be higher than that of the low-grade glioma group (n = 7; Mann-Whitney U-test, p < 0.0167). 201Tl accumulation in the tumor corresponded to contrast enhancement on MRI in 95% of cases. An insufficient blood-brain barrier was considered to be the primary contributor to 201Tl accumulation. In five cases, there was a discrepancy between the extent of 201Tl accumulation and the Gd-DTPA enhanced area. In these cases, the area of 201Tl accumulation was larger than the area of Gd-DTPA enhancement. This may result from damage to the blood-brain barrier that is not severe enough to be detected with Gd-DTPA or from additional factors other than change in the blood-brain barrier. 201Tl-SPECT is able to demonstrate the extent of glioma more accurately than contrast-enhanced MRI.

p38 Mitogen-activated protein kinase regulates IL-8 expression in human pulmonary vascular endothelial cells

The aim of this study was to examine the role of p38 mitogen-activated protein (MAP) kinase in interleukin (IL)-8 expression in tumour necrosis factor (TNF)-alpha- and IL-1alpha-stimulated human pulmonary vascular endothelial cells. To this end, the phosphorylation and activation of p38 MAP kinase and the effect of SB 203580, a specific inhibitor of p38 MAP kinase activity, on p38 MAP kinase activity and IL-8 expression in TNF-alpha- and IL-1alpha-stimulated human pulmonary vascular endothelial cells were examined. TNF-alpha- and IL-1alpha- induced phosphorylation and activation of p38 MAP kinase and IL-8 expression in human pulmonary endothelial cells. Inhibition of TNF-alpha- and IL-1alpha-induced p38 MAP kinase activity by SB 203580 inhibited TNF-alpha- and IL-1alpha-induced IL-8 protein production as well as IL-8 messenger ribonucleic acid (mRNA) expression, indicating that SB 203580 was effective at the transcriptional level. These results indicate that p38 mitogen-activated protein kinase plays an important role in the tumour necrosis factor-alpha- and interleukin-1alpha-activated signalling pathway which regulates interleukin-8 expression in human pulmonary vascular endothelial cells.

Mitogen-activated protein kinase involves neutrophil elastase-induced morphological changes in human bronchial epithelial cells

Neutrophil elastase (NE) promotes the detachment of airway epithelial cells; however, changes in overall morphology of NE-stimulated bronchial epithelial cell (BEC) monolayer are different from trypsin stimulation. Ras/Raf-initiated-mitogen activated protein kinase (MAPK) also known as extracellular signal-regulated kinase, pathway regulates integrin functions which participate in regulating attachment and detachment of cell and cellular morphology. However, little is known about the role of MAPK in NE-induced changes in overall morphology of BEC. In the present study, we examined the role of MAPK in NE-induced changes in overall morphology of BEC monolayer. To this end, we examined changes in cellular morphology and MAPK activation in NE-stimulated BEC monolayer, and the effect of PD 98059 as the specific inhibitor for MAPK kinase-1 (MEK-1, the upstream regulator of MAPK) on NE-induced changes in cellular morphology and MAPK activation. The results showed that in stimulation of NE, BECs detached and gaps developed, and MAPK activation was observed. PD 98059 attenuated NE-induced changes in cellular morphology as well as MAPK activation. These results indicated that in addition to proteolytic activity of NE on extracellular matrix (ECM), NE-activated MAPK pathway, at least in part, is involved in NE-induced changes in overall morphology and the detachment of BEC monolayer.

Thioredoxin negatively regulates p38 MAP kinase activation and IL-6 production by tumor necrosis factor-alpha

We examined the regulatory role of a reduction/oxidation (redox) control protein, thioredoxin (TRX), in tumor necrosis factor-alpha (TNF-alpha)-induced p38 MAP kinase activation and p38 MAP kinase-mediated cytokine expression utilizing TRX-transfected murine L929 cells (TRX14). The results showed that TNF-alpha-induced p38 MAP kinase activation and interleukin-6 (IL-6) production by TRX 14 were less than those by the parental L cells and the control transfected L cells (Neo-1). SB 203580 as the specific inhibitor for p38 MAP kinase activity inhibited TNF-alpha-induced IL-6 production by the parental L cells, indicating that TNF-alpha-activated p38 MAP kinase regulates IL-6 production by the cell lines used in this study. These results showed that overexpression of TRX negatively regulates p38 MAP kinase activation and p38 MAP kinase-mediated IL-6 production by TNF-alpha-stimulated cells, indicating that TRX is critical for p38 MAP kinase activation which regulates cytokine expression.

The origin of hypsarrhythmia and tonic spasms in West syndrome: evidence from a case of porencephaly and hydrocephalus with focal hypsarrhythmia

We report on a 3-year-old girl with West syndrome and with focal hypsarrhythmia. The left hemisphere of the patient was virtually completely defective and continuous hypsarrhythmia was only seen in the residual right frontal cortex, where an interictal single photon emission computed tomography (SPECT) showed hyperperfusion. Despite a focal epileptic pattern, the tonic spasms were quite symmetrical. In our patient, spasms might not require the sensorimotor cortex, but the brainstem containing the descending pathways that control spinal reflexes and other infratentorial structures seem to be essential for the occurrence of spasms. This is in accordance with the result of an ictal SPECT that showed hyperperfusion of the brainstem and cerebellum. These findings suggest that hypsarrhythmia originates from cortical lesions, while subcortical structures may be primarily responsible for the tonic spasms in this patient.

Evaluation of neuronal loss in adult moyamoya disease by 123I-iomazenil SPECT

BACKGROUND

Central benzodiazepine (BZD) receptor imaging is effective to evaluate neuron density in the pathological brain cortex. This study used BZD receptor imaging to evaluate neuronal damage in adult ischemic moyamoya disease.

METHODS

Single photon emission computed tomography and a novel tracer, 123I-iomazenil, were used to measure BZD receptor density in the brain. Evaluation of early and late images was performed in three asymptomatic, unoperated patients, and six mildly symptomatic, operated patients.

RESULTS

Uptakes in the frontal, parietal, and occipital lobes of symptomatic patients were significantly lower (p<0.05) than those of asymptomatic patients. The late image/ early image count ratios (L/E ratios) of asymptomatic patients were relatively constant (mean, 0.571; range, 0.550-0.581) in all regions of interest. In contrast, the L/E ratios of symptomatic patients were not uniform.

CONCLUSIONS

The neuron density was preserved in adult asymptomatic patients despite harboring moyamoya disease. In contrast, the neuronal density was decreased in symptomatic patients even though their symptoms were mild and they had undergone revascularization.

Retinoic acid differentially regulates interleukin-1beta and interleukin-1 receptor antagonist production by human alveolar macrophages

Mechanism in the pathogenesis of acute respiratory distress syndrome which is the clinical feature of pulmonary involvement in retinoic acid (RA) syndrome has been investigated. Pulmonary infiltration of matured neutrophils and leukemic cells is thought to be associated with the pathogenesis of pulmonary involvement in RA syndrome; however. Little is known about the mechanism in pulmonary infiltration of these cells. In the present study, we examined the effect of RA on IL-1beta and IL-1ra production by human alveolar macrophages in order to clarify the mechanism in pulmonary infiltration of neutrophils, since IL-1 has been shown to initiate neutrophil recruitment into the lung through up-regulated expression of adhesion molecules on vascular endothelium. RA enhanced IL-1beta and inhibited IL-1ra production by 4beta phorbol 12beta-myristate-13alpha acetate (PMA)- and lipopolysaccharide (LPS)-stimulated human alveolar macrophages. These results show that RA differentially regulates IL-1beta and IL-1ra production by alveolar macrophages and indicate that an imbalanced production between IL-1beta and IL-1ra may contribute to initiating neutrophil recruitment into the lung through up-regulated expression of adhesion molecules.

[Hepatic clearance of 99mTc-GSA in cases of postoperative biliary atresia--a retrospective comparison with hepatic clearance of 99mTc-PMT]

There are a few reports about usefulness of 99mTc-GSA liver scintigraphy (GSA imaging) for the evaluation of postoperative state of biliary atresia. However, comparison of significance for the disease between GSA imaging and 99mTc-PMT hepatobiliary imaging have not been reported. Fifty-six GSA imagings for 41 postoperative biliary atresia patients were reviewed and their scintigraphic findings and the functional parameters were compared with those obtained from 99mTc-PMT hepatobiliary imaging. In quantitative analysis, although the hepatic clearance of both tracers calculated by graphical analysis (Patlak plot) were well correlated in most cases, a discrepancy was observed in several cases with jaundice. The authors conclude that the hepatic clearance of 99mTc-GSA is a more accurate index of the hepatic reserve than that of 99mTc-PMT which can be influenced by hyperbilirubinemia and that the combination of both examinations is helpful to evaluate development of liver injury in postoperative biliary atresia patients.

Heterogeneity of ictal SPECT findings in nine cases of West syndrome

We evaluated the ictal and interictal single photon emission computed tomography (SPECT) of 9 patients with West syndrome (WS). In this group, we noted two clear patterns of cortical hyperperfusion and subcortical hyperperfusion in the ictal SPECT. Both patterns were different from the previously documented ictal patterns for complex partial seizures (CPS) or secondarily generalized seizures. Our results suggest that the tonic spasms of WS do not always have a single neurophysiological basis; e.g., patients with hemihypsarrhythmia and focal hypsarrhythmia did not show ictal hyperperfusion of the lesion with hypsarrhythmia. These findings indicate that the origin of hypsarrhythmia as an EEG feature and the origin of tonic spasms may be different in such patients. In particular, hypsarrhythmia appears to originate from cortical lesions, whereas the subcortical structures may be primarily responsible for the tonic spasms. Our report is the first published study of ictal SPECT in patients with WS.

Hemorrhage in pituitary adenoma: correlation of MR imaging with operative findings

The aim of this study was to correlate MR imaging and operative findings of hemorrhage in pituitary macroadenomas. We retrospectively reviewed MR images of 113 surgically proven pituitary adenomas. All patients were examined on a 1.5-T MR system. The intensity of intratumoral cystic cavities was correlated with operative findings. In 15 patients with pituitary apoplexy, we determined relationship between interval of MR examination after apoplectic event and MR signal intensity. In 8 patients with repeated preoperative MR examination, we evaluated sequential changes of intratumoral hemorrhage. There were 54 cavities at surgery: 52 were hemorrhagic and 2 were nonhemorrhagic. Twenty-nine of 52 hemorrhagic cysts demonstrated high/low signal (H/L) fluid-fluid levels on T2-weighted image (T2WI). In 19 of them, two components could be separately seen at operation: the supernatant high-intensity area represented xanthochromic fluid, and the dependent low-intensity area represented liquefied hematoma. The H/L fluid-fluid level was observed predominantly in hematomas on MR images obtained after longer intervals. In patients with repeated MR examination, follow-up MR imaging revealed additional hemorrhage or new formation of fluid-fluid levels. It was surprising that 12 of 14 cysts preoperatively judged as nonhemorrhagic in fact contained hemorrhagic components. The preoperative MR images are well correlated to the operative findings in hemorrhagic pituitary macroadenomas. It proved that 52 of 54 cystic cavities had hemorrhagic component.

Correlation of plasma monocyte chemoattractant protein-1 (MCP-1) and monocyte inflammatory protein-1alpha (MIP-1alpha) levels with disease activity and clinical course of sarcoidosis

MCP-1 and MIP-1alpha exhibit chemotactic activity toward macrophages/monocytes and induce the production of inflammatory cytokines affecting granuloma formation. Up-regulated expression of MCP-1 and MIP-1alpha in the affected organ of sarcoidosis has been shown; however, the relationship between their plasma levels and the clinical course of this disease has not been determined. In the present study we measured plasma MCP-1 and MIP-1alpha levels in 26 patients with active sarcoidosis by ELISA in order to assess the state of MCP-1 and MIP-1alpha in this disease. Most patients in this study (21/26) had clinical evidence of extrathoracic disease in addition to pulmonary involvement. In addition, a high proportion of patients (n = 15) showed spontaneous remission of disease, whereas five patients showed no spontaneous remission and six patients were treated with corticosteroids over the 2-year period of study. At the time of diagnosis, both plasma MCP-1 and MIP-1alpha levels in patients with active sarcoidosis were significantly higher than in the normal controls. The levels of these cytokines in patients with extrathoracic disease were compatible with those in patients without extrathoracic disease. A longitudinal evaluation of plasma MCP-1 and MIP-1alpha levels showed that the changes in both cytokines were closely related to the clinical course of sarcoidosis. These results suggest that plasma MCP-1 and MIP-1alpha may be useful parameters for monitoring the clinical course of sarcoidosis. In addition, plasma MCP-1 and MIP-1alpha may reflect subclinical evidence of extrathoracic sarcoidosis and may play a role in initiating monocyte migration into the tissue.

[New methods for measuring atlanto-axial vertical subluxation in rheumatoid arthritis by MR imaging]

We proposed two new methods of measuring atlanto-axial vertical dislocation in rheumatoid arthritis by MR imaging. One is the distance from the subdental synchondrosis of the axis to the diameter of the ring of the atlas. The other is the distance from the midpoint of the anteroposterior ends of the inferior margin of the axis to the diameter of the ring of the atlas. Values were also determined by the Ranawat method and the Redlund-Johnell method. There was good correlation between values determined by the new methods and those determined by the Ranawat method and Redlund-Johnell method.

Functional MR imaging of cortical activation of the cerebral hemispheres during motor tasks

PURPOSE

We used functional MR imaging to evaluate cortical activation in the precentral, central, and postcentral regions of the contralateral and ipsilateral cerebral hemispheres during left- and right-handed motor tasks.

METHODS

Ten healthy right-handed volunteers were studied with echo-planner MR imaging (1.5 T) while performing alternating finger apposition tasks with both hands. During the hand tasks, the areas of activated pixels were compared between subregions (precentral, central, and postcentral) of the contralateral and ipsilateral sensorimotor cortex.

RESULTS

The activated area of the contralateral sensorimotor cortex was significantly larger than that of the ipsilateral cortex during tasks with either hand, whereas the ipsilateral activated area was significantly larger during the left-handed task than during the right-handed task. Ipsilateral activation was greatest in the precentral region, less in the central region, and least prominent in the postcentral region.

CONCLUSIONS

Our results confirmed those of previous investigators that ipsilateral activation is more pronounced during left-sided movements than during right-sided movements. The variation in activation of the precentral, central, and postcentral subregions suggests different roles of the ipsilateral and contralateral hemispheres during motor tasks.

[Can 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) evaluate the renal function without blood sampling?: consensus report from multicenter study]

A multicenter study was undertaken in Japan to evaluate the correlation between the percentage of renal uptake of 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) estimated by the count-based gamma camera method and the blood clearance of 99mTc-MAG3. Twenty four centers were enrolled and 172 cases were finally analyzed in this study. The renal clearance of 99mTc-MAG3 (TER) was obtained by using a single blood sample taken at 44 min after injection. Comparison of TER and renal uptake provided a coefficient of correlation of 0.874; suggesting that sufficiently accurate quantification of renal function could be obtained from the renal uptake estimate by the gamma camera method. This study also showed that the comparison of renal function might be feasible among patients under the same protocols, although precise and careful consideration is required in each center.

[Effects of combination chemoradiotherapy with daily low-dose CDDP for esophageal cancer--results of a randomized trial]

Between 1994 and 1996, 24 patients with esophageal carcinoma were entered in a randomized clinical trial comparing radiotherapy (RT) only (arm A) versus RT and a daily low dose of CDDP (5 mg/m2) (arm B). For arm B group, CDDP was injected within 30 min after irradiation. All patients were irradiated with a total dose of 60 Gy /30fr. at first, and some patients were boosted. An overall response rate of 75.0% (complete response rate of 25.0%) was observed in arm A and 91.7% (complete response rate of 16.7%) in arm B, respectively. The survival rate at 1 year was 23.8% in arm A and 40.0% in arm B. Median survival time was 7 months in arm A and 9 months in arm B. Toxicity was acceptable and no significant difference was noted between arm A and arm B.

N-acetylcysteine attenuates TNF-alpha-dependent reduction of IL-4-induced Fc epsilon RII expression in human monocytes

We have previously shown that tumor necrosis factor-alpha (TNF-alpha) reduces interleukin-4 (IL-4)-induced Fc epsilon RII expression in human monocytes. It has been shown that TNF-alpha activates nuclear transcriptional factors through the generation of reactive oxygen intermediates (ROIs), and antioxidant N-acetylcysteine (NAC) inhibits TNF-alpha-induced activation of nuclear transcriptional factors. Therefore, we hypothesized that TNF-alpha-dependent reduction of IL-4-induced Fc epsilon RII expression in monocytes might be mediated through the ROIs-activated mechanism. In the present study, to test our hypothesis, we examined the effect of NAC on TNF-alpha-dependent reduction of IL-4-induced Fc epsilon RII expression in human monocytes. NAC attenuated TNF-alpha-dependent reduction of IL-4-induced Fc epsilon RII expression by attenuating TNF-alpha-dependent reduction of Fc epsilon RII mRNA expression. Similarly, the structurally unrelated antioxidant, pyrrolidine dithiocarbamate (PDTC), also effectively attenuated this-reduction. These results indicate that an ROIs-activated and antioxidant-sensitive mechanism might be involved in TNF-alpha-dependent reduction of IL-4-induced Fc epsilon RII expression in monocytes.

[Cine display of postprocessed 3D MR images of the thoracic aorta]

We have developed a cine display of postprocessed 3D MR images of the thoracic aorta. Maximum intensity projection (MIP) images of the thoracic aorta in each phase were reconstructed from consecutive 2D-cine MR data sets, and displayed in a cine loop. The postprocessed 3D MR images clearly showed the relationship between major cervical branches and aortic pathologies such as aneurysms, and cine display presented the flow pattern in the aorta. 3D-cine MR angiography seems to be useful for follow-up studies of thoracic aortic diseases especially in patients with renal dysfunction.

[Evaluation of clinical utility of 111In-DTPA-IgG scintigraphy in the detection of inflammation/infection--a report of multicenter phase III clinical trials]

This is the report of phase III study to evaluate the safety and utility of 111In-DTPA-IgG in patients with strongly suspected inflammation/infection. One hundred and forty five patients with suspected sites of inflammation/infection were enrolled in the study. Only a few adverse experiences in one patient were reported, which were interpreted as having a possible relationship to the agent. A total of 171 suspected sites (12 in head and neck, 39 in thorax, 44 in abdomen and pelvis, 62 in musculoskeletal system, and 14 in other regions) were evaluated by investigators at each institute. Out of 171 sites, 18 were determined to be unevaluable, and 12 false negative and 5 false positive cases were observed. Overall sensitivity and specificity was 89.8% and 85.7%, respectively, and the agent proved to be effective in detecting lesions anywhere throughout the body. The analysis of data from this Phase III study indicates that 111In-DTPA-IgG is well-tolerated in patients and effective in determining focal sites of inflammation/infection although the physiological accumulation in some tissues such as the sinus or liver and possible excretion into the gastrointestinal tract may make it difficult to localize lesions.

Restoration of the mucociliary clearance of the maxillary sinus after endoscopic sinus surgery

BACKGROUND

Whether endoscopic sinus surgery (ESS) restores the mucociliary clearance of the maxillary sinus needs further evaluation.

METHODS

We evaluated the mucociliary clearance of the maxillary sinus by using a radionuclide technique in 12 patients with chronic sinusitis (sinusitis group) and in six patients who had undergone ESS 6 to 14 months after the surgery (post-ESS group). The mucosal cilia taken from the maxillary sinus in 12 patients with sinusitis before and after ESS (paired experiments) were examined by light and electron microscopy.

RESULTS

The radionuclide placed endoscopically in the maxillary sinus in eight patients immediately after ESS maintained 81.2 +/- 16.3% of its radioactivity after 30 minutes. This result was consistent with results in four patients with untreated chronic sinusitis in whom the radionuclide had been instilled by antral puncture (86.9% +/- 3.5%). On the other hand, in six patients in the post-ESS group the radionucleotide maintained only 25.9% +/- 11.6% of its radioactivity, demonstrating statistically significant differences from those of both the sinusitis group without ESS (p < 0.005) and the group 4 days after ESS (p < 0.005). The absence of the cilia in the sinusitis condition was recognized in 35.5% +/- 12.1% (n = 12) of the epithelial cells. On the other hand, the absence of cilia was significantly (p < 0.01) reduced to 5.3% +/- 3.7% of the epithelial cells in the post-ESS condition. Electron microscopic observation also revealed abnormal cilia in the sinusitis condition, whereas the mucosal cilia were regularly arranged in the post-ESS condition.

CONCLUSIONS

The mucociliary clearance of the maxillary sinus disturbed by chronic inflammation was restored by ESS, indicating the clinical effectiveness of ESS for the treatment of chronic sinusitis.

[Quantification of renal function with 99mTc-MAG3--quantification of tubular extraction rate using Bubeck's method]

99mTc-mercaptoacetyltriglycine (MAG3) is a new agent for dynamic renal scintigraphy. It provides not only superior quality of imaging to conventional agents such as 131I-orthoiodohippurate or 99mTc-demethylenetriaminepantaacetic acid but also quantification of renal function as do the latter agents. The aim of the present study was to evaluate the value of the tubular extraction rate (TER) using 99mTc-MAG3 calculated by Bubeck's method, a simple technique for quantifying renal function. In 31 patients with renal disorders, we compared the TER thus obtained with laboratory data, plasma paraaminohippurate clearance, effective renal plasma flow calculated by Tauxe's method, and plasma 99mTc-MAG3 clearance calculated according to the two-compartment model. TER was easily applicable in clinical settings, and showed close parallels with the other indexes of renal function. We believe, therefore, that it can serve as a useful parameter of renal function.

[Gastric emptying of semi-solid meal in normal man with special reference to relationship between plasma acetoaminophen concentrations and gastric emptying time]

Correlation between gastric emptying time measured by a radioisotope method and plasma acetoaminophen level was studied in 11 preoperative early gastric cancer in semisolid meal. A significant correlation was found between both gastric emptying half-time and plasma acetoaminophen level at 30, 45 minutes after ingestion of meal, and plasma acetoaminophen level at maximum. We conclude that acetoaminophen analysis is useful to measure gastric emptying at semisolid meal.

A simple maneuver in follow-up digital subtraction angiography for multiple coronary-aorta bypass grafts

A simple maneuver in intraarterial digital subtraction angiography (DSA) is proposed to improve the images of left internal thoracic artery bypass grafts (LITAGs). A contrast flush in the left subclavian artery, using a catheter that had been percutaneously introduced from the left brachial artery, was carried out in 14 patients with multiple coronary-aorta bypass grafts (CABGs) after aortic DSA. The side-hole portion of the catheter tip was positioned in the proximal left subclavian artery as the coiled portion remained in the aortic arch. Nonionic contrast medium (350 mg/ml of iodine) was injected with an automatic injector in a volume of 6-8 ml and at a flow rate of 3-4 ml/sec. Left subclavian arterial flush DSA delineated the LITAGs excellently in 11, well in 3, and fairly or poorly in none of the 14 cases. There were no complications in any of these cases. A supplemental contrast flush of the left subclavian artery with a pigtail catheter following aortic DSA improves the diagnosis of multiple CABG patency.

MR findings of avulsive cortical irregularity of the distal femur

Avulsive cortical irregularity, a benign condition occurring only among children and adolescents, has been known to simulate malignancy not only radiologically but also microscopically. Therefore, in addition to plain radiographs, further studies including by magnetic resonance (MR) imaging may occasionally be required. MR images of seven cases of avulsive cortical irregularity of the femur were reviewed. In all cases, the lesion appeared hypointense on T1-weighted images and hyperintense on T2-weighted images, with a dark rim on both sequences at or near the sites of the bony attachment of the medial head of the gastrocnemius muscle. In all cases, bilateral involvement was demonstrated by plain radiography, computed tomography, and/or MR imaging. The authors suggest that avulsive cortical irregularity involves both femora much more frequently than has been reported previously.