Disseminated Pneumocystosis in a Toy Poodle

A 1-year and 7-months-old neutered male toy poodle was presented with persistent respiratory distress, gradual weight loss and melaena. Thoracic radiography showed an unstructured interstitial lung pattern. Histopathological examination of tissues collected at necropsy examination revealed disseminated infection by Pneumocystis carinii. The organisms were detected in the lungs, lymph nodes, liver, heart, kidneys, spleen, gastrointestinal tract and pancreas. In the lungs, the organisms were present in the alveolar space and interstitial tissue, and calcified foci containing P. carinii were observed. The presence of the organism in non-thoracic lymph nodes provided evidence of lymphogenous spread. A definitive diagnosis of disseminated pneumocystosis was achieved through the use of Grocott methenamine silver staining, immunohistochemistry (IHC) and polymerase chain reaction for P. carinii. Depletion of cells expressing immunoglobulin (Ig)A and IgG was confirmed by IHC of lymphoid tissue, suggesting possible underlying immunodeficiency.

Community-based screening intervention for depression affects suicide rates among middle-aged Japanese adults

BACKGROUND

It has been suggested that screening interventions may be effective for suicide prevention. Few studies, however, have reported their effects on outcome measures, including death by suicide among middle-aged adults.

METHOD

We used a quasi-experimental parallel cluster design with matched community-based intervention and control municipalities (total eligible population: 90 000) in Japan. At-risk residents within the intervention area were invited for universal depression screening and subsequent care/support. We compared changes in suicide incidence of adults aged 40-64 years for the 4-year pre- and post-implementation periods in the intervention group with the control group and the whole country. Incidence rate ratios (IRRs) of the outcomes were adjusted for age group, gender and interaction terms, using mixed-effects negative binomial regression models. Suicide rates among intervention and control subgroups were compared.

RESULTS

The screening procedure was offered to 52% of the intervention group, and 61% of those contacted responded over the implementation period. Suicide rates decreased more in the intervention group [IRR 0.57, 95% (CI) 0.41-0.78; F 1,36 = 12.52, p = 0.001] than the control group (IRR proportion 1.63, 95% CI 1.06-2.48; F 1,82 = 5.20, p = 0.025) or the whole country (IRR proportion 1.64, 95% CI 1.16-2.34; F 1,42 = 8.21, p = 0.006). Sensitivity analyses confirmed the results from the primary analysis. There were lower suicide rates among both respondents and non-respondents to the screening than in the control group during the implementation period.

CONCLUSIONS

Prevention efforts involved in the depression screening intervention were probably successful in reducing suicide rates.

Usefulness of Pseudocontinuous Arterial Spin-Labeling for the Assessment of Patients with Head and Neck Squamous Cell Carcinoma by Measuring Tumor Blood Flow in the Pretreatment and Early Treatment Period

BACKGROUND AND PURPOSE

For the assessment of the treatment response in non-surgical treatment, tumor blood flow provides the functional information of the tumor which is different from the morphological information such as tumor volume. The purpose of this study was to evaluate the diagnostic value of tumor blood flow values obtained by pseudocontinuous arterial spin-labeling in patients with head and neck squamous cell carcinoma.

MATERIALS AND METHODS

Forty-one patients with head and neck squamous cell carcinoma were evaluated by using pseudocontinuous arterial spin-labeling. Quantitative tumor blood flow was calculated at the pretreatment and the early treatment periods in all the patients, and the percentage change of tumor blood flow between the two was calculated. At the early treatment period, based on their tumor volume reduction rate, we divided the patients into stable disease and partial response groups for a subgroup analysis. The local control or failure was confirmed either by histopathology or by radiologic evaluation within the follow-up.

RESULTS

Pretreatment tumor blood flow in patients in the failure group was significantly lower than that in patients in the local control group. In the subgroup analysis of patients with stable disease, the percentage change of tumor blood flow was significantly larger (due to the tumor blood flow increase from pretreatment value) in the local control group than in the failure group. In addition, in patients with a partial response, the percentage change of tumor blood flow was significantly smaller (due to the tumor blood flow decrease from the pretreatment value) in the local control group than in the failure group. The accuracy for determination of the local control group or the failure group in pretreatment tumor blood flow was 0.83 and that in the combination use of the percentage change of tumor blood flow and tumor volume in the early treatment period was 0.93.

CONCLUSIONS

Tumor blood flow obtained by pseudocontinuous arterial spin-labeling can be useful for the determination of local control. The combined use of the percentage change of tumor blood flow and tumor volume had particularly high diagnostic accuracy.

Positron emission tomography-computed tomography can be useful in the early detection of metastases in primary mucinous carcinoma of the skin on the head and neck

Primary mucinous carcinoma of the skin (PMCS) is a rare cutaneous malignant neoplasm; its regional node metastasis is also rare. Currently, positron emission tomography-computed tomography (PET-CT) is known to be a useful tool to search for early metastatic lesions in various carcinomas. However, PET-CT is not always specific for head and neck lesions because of physiological uptake in the brain, palatine tonsil, salivary gland, thyroid etc. Herein we present two cases of head and neck PMCS in which metastasis was diagnosed accurately by PET-CT. In these cases, nodal uptake of fluorodeoxy-d-glucose (FDG) histopathologically proved PMCS metastasis, verifying the utility of PET-CT in detail. A surgeon was involved in the verification to compare the histopathological manifestations with the imaging results. Histopathologically, two of 13 nodes were positive in case 1, and one of 41 nodes was positive in case 2. These positive nodes were completely in accordance with the FDG uptake findings with no false negative findings. In treating PMCS on head and neck lesions, PET-CT may be useful in the preoperative assessment when planning the extent of resection.

Differentiation of squamous cell carcinoma and inverted papilloma using non-invasive MR perfusion imaging

OBJECTIVES

To investigate the diagnostic value of tumour blood flow (TBF) obtained with pseudocontinuous arterial spin labelling for the differentiation of squamous cell carcinoma (SCC) and inverted papilloma (IP) in the nasal or sinonasal cavity.

METHODS

We retrospectively analysed the cases of 33 patients with SCC and 8 patients with IP in the nasal or sinonasal cavity. Pseudocontinuous arterial spin labelling scanning was performed for all patients using a 3.0-T MR unit. Quantitative TBF values were measured by two neuroradiologists by respectively delineating the whole-tumour regions of interest, and the mean of them was determined as TBF value in each patient. Additionally, the presence of imaging findings of convoluted cerebriform pattern (CCP) on MR T2 weighted images was determined in all patients. As a subgroup analysis, patients with IP were divided into aggressive and non-aggressive IPs depending on their progression range. First, an intraclass correlation coefficient (ICC) of TBF values between two neuroradiologists was determined. Next, a statistical comparison of the TBF value by a Mann-Whitney U test between the patients with SCC and IP was performed. Additionally, the comparison by an ANOVA with a post hoc test of Tukey's method among the SCC, non-aggressive IP and aggressive IP groups was also performed. If significance was observed, the diagnostic accuracy to differentiate SCCs from IPs was calculated. Diagnostic accuracy by CCP findings alone and by the combination of CCP findings and TBF were also assessed.

RESULTS

The ICC of TBF values between two neuroradiologists was 0.82. The mean TBF values in the patients with SCC, all patients with IP, those with aggressive IP and those with non-aggressive IP were 141.2 ± 33.1, 77.8 ± 31.5, 109.4 ± 16.7 and 58.8 ± 19.9 ml 100 g⁻¹ min⁻¹, respectively. A significant difference was observed between SCC and IP (p < 0.001), SCC and non-aggressive IP (p < 0.01) and non-aggressive IP and aggressive IP (p < 0.01). The diagnostic accuracy values obtained with receiver operating characteristic curve analysis for the differentiation of SCC from IP and for SCC from non-aggressive IP were 0.90 and 0.92, respectively. The diagnostic accuracy was elevated (0.95 from 0.88) by adding the TBF value to CCP findings.

CONCLUSIONS

The pseudocontinuous arterial spin labelling technique can be a useful non-invasive diagnostic tool to differentiate SCC from IP in nasal or sinonasal cavity.

Strict limit on CPT violation from polarization of γ-ray bursts

We report the strictest observational verification of CPT invariance in the photon sector, as a result of γ-ray polarization measurement of distant gamma-ray bursts (GRBs), which are the brightest stellar-sized explosions in the Universe. We detected γ-ray polarization of three GRBs with high significance levels, and the source distances may be constrained by a well-known luminosity indicator for GRBs. For the Lorentz- and CPT-violating dispersion relation E(±)(2) = p(2) ± 2ξp(3)/M(Pl), where ± denotes different circular polarization states of the photon, the parameter ξ is constrained as |ξ|<O(10(-15)). Barring precise cancellation between quantum gravity effects and dark energy effects, the stringent limit on the CPT-violating effect leads to the expectation that quantum gravity presumably respects the CPT invariance.

A case study of radon-222 transport from continental North-East Asia to the Japanese islands in winter by numerical analysis

A case study of the regional transport ( approximately 3000 km) of radon-222 ((222)Rn) from continental North-East Asia to the Japanese islands was performed by numerical analysis using five separate source areas (South, Middle and North China, Russia and Korea), while a seasonal northwest wind blew over the Japan Sea. The results for three periods (Term I: 16-18, Term II: 22-25 and Term III: 27-28 in December 1990) were compared with concentrations measured at the Kanazawa site (near the coast of the Japan Sea facing the seasonal wind) and the Nagoya site (overland and downwind on the shores of the Pacific Ocean). Most of the (222)Rn at the Kanazawa site was calculated to come from North China and Korea in Term I, Middle China, North China, and Korea in Term II, and Russia and Korea in Term III. The considerable differences in the origins of (222)Rn emanated from the continent were estimated between Terms I, II and III, even though the similar northwest wind was dominant over the Japan Sea. A contour line analysis indicated movement of (222)Rn emanated from Middle China in a northerly direction first and then a southeasterly direction, resulting from low pressure. The results suggest that the low-pressure systems play an important role in the transport of (222)Rn in North-East Asia.

High-energy carbon ion irradiation and the inhibition of negative gravitaxis in Euglena gracilis Z

PURPOSE

To study the effects of high-energy carbon ion irradiation on negative gravitaxis in the photosynthetic flagellate Euglena gracilis strain Z in a dose-response-dependent manner.

MATERIALS AND METHODS

Cells were exposed to 290 MeV amu(-1) carbon ion from the Heavy Ion Medical Accelerator in Chiba (HIMAC) at 12 doses (0, 1, 5, 7.5, 10, 15, 20, 50, 75, 100, 150, 200 Gy for water). r was used to quantify negative gravitaxis observed in a recently developed biomonitoring system.

RESULTS

Negative gravitaxis of Euglena was significantly affected by irradiation at a dose >7.5 Gy, 28 h after irradiation. Negative gravitaxis recovered after a few days. The rising phase of r during the first 30 s of orientation was independent of irradiation dose. The recovery mechanism itself was damaged by 290 MeV amu(-1) carbon ions at a dose >50 Gy.

CONCLUSIONS

The results indicate that negative gravitaxis in Euglena may be affected by the radiation experienced during a space experiment especially during the occurrence of solar flares. The analyses of time needed to reorient to the gravitational vector suggest that the steering control of the flagellar apparatus is affected by exposure to the 290 MeV amu(-1) carbon ion irradiation, resulting in an altered beating pattern of a flagellum and/or changes of the cell form during reorientation.

Gamma-irradiation effect: variation of photosynthetic activity of Euglena

OBJECTIVE

To study the effects of gamma-ray irradiation on carbon fixation (Specific production rate: SPR), CO2 utilization efficiency (CUE) and electron transfer rate (ETR) in the photosynthetic flagellate Euglena gracilis strain Z in a dose-response dependent manner.

METHODS

Euglena cells were cultured in an inorganic nutrient medium containing ammonium chloride or proteose peptone. Cells were exposed to gamma-ray at 5 doses (0, 100, 250, 350, 500 Gy for water). Five days after irradiation, three photosynthetic activities were measured. SPR, which is a carbon uptake rate per unit carbon mass, was determined by 13C tracer methodology. CUE was evaluated using a relation of carbon isotope fractionation in Calvin cycle. ETR in photosystem II (PS II) was measured by a chlorophyll fluorescence analysis.

RESULTS

Even at a dose of 500 Gy, 80% of ETR of the non-irradiated control (0 Gy) was sustained, while SPR and CUE were about half the level in the non-irradiated control at 500 Gy. Furthermore, the dose response of ETR was considerably different from the others.

CONCLUSION

Our findings suggest that not only PS II but also the Calvin cycle in the photosynthetic system is affected by gamma ray irradiation.

Effects of gamma-ray and high energy carbon ion irradiation on swimming velocity of Euglena gracilis

The effects of gamma-ray and high energy carbon ion irradiation on the swimming velocity of the photosynthetic flagellate Euglena gracilis strain Z were studied, focusing on a dose-effect relationship. Cells were exposed to 60Co gamma-rays at 6 doses of 10, 15, 20, 40, 100 and 200 Gy for water, and also to 290 MeV/amu carbon ions from the Heavy Ion Medical Accelerator in Chiba at 7 doses (5, 10, 15, 20, 50, 100 and 200 Gy for water). The swimming velocity was measured by a biomonitoring system, called ECOTOX. The swimming velocities of Euglena gracilis cells were significantly decreased by >40 Gy gamma-rays and >5 Gy carbon ions, respectively. The 50% effective doses for inhibition, 34 +/- 4 Gy (gamma-rays) and 13 +/- 1 Gy (290 MeV/amu carbon ions), were estimated from the best fit to data of the logistic model. The relative biological effectiveness (2.6 +/- 0.4) was calculated by the ratio of 50% effective doses. The inhibition of the swimming velocity of the cells irradiated with gamma-rays was still present after 3 days, while recovery of the swimming velocity was shown in the cells exposed to 290 MeV/amu carbon ions. It is suggested that ionizing radiation inhibits ATP production and/or increases frictional drag on beating of the flagellum, thus decreasing swimming velocity.

Estrogen replacement therapy in postmenopausal women augments reactive hyperemia in the forearm by reducing angiotensin converting enzyme activity

The precise mechanism of the vasoprotective effect of estrogen replacement therapy in postmenopausal women is not fully understood. The present study sought to determine the role of nitric oxide (NO) and angiotensin-converting enzyme (ACE) in the vasodilator response of the forearm vessels induced by estrogen administration to postmenopausal women. Subjects were divided into two groups. One group received conjugated equine estrogen (0.625 mg daily) orally for 3 months (n=26), while the other received no treatment (control group, n=10). Forearm blood flow was measured by strain-gauge plethysmography. The concentrations of nitrite/nitrate (metabolites of NO), ACE activity, and lipid parameters were measured. Basal forearm blood flow, body weight, blood pressure, and heart rate were similar at baseline in both groups. After 3 months of estrogen administration, the maximal forearm blood flow response during reactive hyperemia and the serum level of nitrite/nitrate each showed a significant increase over baseline values: from 23.6+/-2.0 to 36.5+/-3.1 ml/min per 100 ml tissue (P<0.01), and from 24.8+/-2.3 to 38.6+/-3.6 micromol/l (P<0.01), respectively. Plasma levels of ACE activity were significantly reduced from baseline after 3 months of estrogen treatment (from 12.2+/-0.6 to 10.9+/-0.6 IU/l, P<0.01). No changes were seen in controls. The change in forearm blood flow after sublingual nitroglycerin was similar at baseline versus after 3 months of estrogen administration. The increase in the serum level of nitrite/nitrate after 3 months of estrogen therapy showed a significant inverse correlation (r=0.52, P<0.01) with the reduction in the plasma level of ACE activity. There was no significant correlation between the increase in serum nitrite/nitrate and any change in serum lipids, blood pressure, or other parameters. The administration of oral estrogen to postmenopausal women for 3 months increased the NO-mediated forearm endothelium-dependent vasodilatation. This was likely due, at least in part, to ACE inhibition. The latter may be one mechanism by which ERT provides its well-known cardiovascular benefit.

Low density lipoprotein receptor-related protein is required for macrophage-mediated oxidation of low density lipoprotein by 12/15-lipoxygenase

The oxidative modification of low density lipoprotein (LDL) has been implicated in the early stage of atherosclerosis through multiple potential pathways, and 12/15-lipoxygenase is suggested to be involved in this oxidation process. We demonstrated previously that the 12/15-lipoxygenase overexpressed in mouse macrophage-like J774A.1 cells was required for the cell-mediated LDL oxidation. However, the mechanism of the oxidation of extracellular LDL by the intracellular 12/15-lipoxygenase has not yet been elucidated. In the present study, we found that not only the LDL receptor but also LDL receptor-related protein (LRP), both of which are cell surface native LDL-binding receptors, were down-regulated by the preincubation of the cells with cholesterol or LDL and up-regulated by lipoprotein-deficient serum. Moreover, 12/15-lipoxygenase-expressing cell-mediated LDL oxidation was decreased by the preincubation of the cells with LDL or cholesterol and increased by the preincubation with lipoprotein-deficient serum. Heparin-binding protein 44, an antagonist of the LDL receptor family, also suppressed the cell-mediated LDL oxidation in a dose-dependent manner. The cell-mediated LDL oxidation was dose-dependently blocked by an anti-LRP antibody but not by an anti-LDL receptor antibody. Furthermore, antisense oligodeoxyribonucleotides against LRP reduced the cell-mediated LDL oxidation under the conditions in which the expression of LRP was decreased. The results taken together indicate that LRP was involved essentially for the cell-mediated LDL oxidation by 12/15-lipoxygenase expressed in J774A.1 cells, suggesting an important pathophysiological role of this receptor-enzyme system as the initial trigger of the progression of atherosclerosis.

[Changes in otoacoustic emission during the glycerol test in the ears of patients with Meniere's disease]

Monitoring of cochlear function is one proposed clinical application of otoacoustic emission (OAE). To determine the clinical utility of OAE in monitoring, we studied changes in OAE during the glycerol test used to diagnose endolymphatic hydrops. Transiently evoked OAE (TEOAE) and distortion product OAE (DPOAE) were measured before and 3 hours after oral administration of glycerol in 22 ears of patients with Meniere's disease. The positive result in the glycerol test was observed in 11 of 22 ears. TEOAE was recorded using a nonlinear click stimulus, and total echo power (TEP) of the whole response and filtered echo power (FEP) of its mid-frequency (1000-2000 Hz) component were used as TEOAE parameters. The growth functions of DPOAE were recorded at 3 F2 frequencies--1000, 1500, and 2000 Hz. Changes in the growth function were determined based on changes in 2 parameters--maximum level and detection threshold of DPOAE. When changes in these 4 parameters exceeded 2 standard deviations above mean test-retest variability determined from OAE data for 17 normal ears, they were considered significant. Significant changes indicating improved cochlear function in 4 OAE parameters or the appearance of OAE during the glycerol test were judged positive for OAE. Regardless of glycerol test results, positive findings were observed in both OAEs whenever a pure-tone threshold at 1000 or 2000 Hz improved. However, even in ears for which pure-tone thresholds at these frequencies did not improve, both OAEs frequently exhibited positive findings. In all ears with a positive result in the glycerol test, positive findings were observed in DPOAE, but not in TEOAE. Of the 2 parameters of TEOAE, FEP always exhibited a positive finding in ears with a positive TEP finding and FEP positivity was higher than that of TEP. In DPOAE, no cases showed a positive finding only at F2 = 2000 Hz, and DPOAE at F2 = 1000 Hz could not be detected in 4 ears due to high noise floor. Overall, positive findings were obtained in 14 ears (63.9%) for TEOAE and 20 ears (90.9%) for DPOAE. In only 1 ear were no positive findings observed in either OAE. The sensitivity of OAE measurement as a diagnostic test for endolymphatic hydrops was higher than that of pure-tone audiometry. Of the 2 OAEs, test sensitivity was much higher for DPOAE than for TEOAE. These results show that OAE measurement detects changes in cochlear function during the glycerol test more sensitively than pure-tone audiometry. They also suggest that FEP is a better indicator than TEP as a parameter of TEOAE, and that DPOAE measurement at F2 = 1000 and 1500 Hz is sufficient for practical clinical use. However, of the 2 OAEs, DPOAE was considered more appropriate than TEOAE for monitoring during the glycerol test because of its high sensitivity in detection of changes in cochlear function. In conclusion, clinical use of OAE, especially DPOAE, as a test complementary to pure-tone audiometry during the glycerol test is very useful and will improve the diagnosis of endolymphatic hydrops.

Lifetime risk of lung cancer due to radon exposure projected to Japanese and Swedish populations

Lifetime risk projections depend greatly on both background lung cancer rates and the selection of the risk model. Since background lung cancer rates differ from subject populations and the time, etiological risk of lifetime lung cancer mortality per unit radon exposure in WLM should be estimated for each subject population and the time of interest. To answer quantitatively how much are the differences among the projected risks for different populations, the Swedish case-control-study-based risk projection model was applied to the Japanese and Swedish populations from 1962 to 1997 as subject populations because of their distinct trends of lung cancer rates. To compare the results with the reference population and authorized risk projection models, U.S. population 1997 and the two risk projection models in BEIR VI report were applied, respectively. Lifetime risk of lung cancer mortality projected for Japanese, Swedish, and U.S. populations in 1997 per radon progeny exposure were estimated to range from 1.50 (0.40-3.19) x 10(-4) WLM(-1) to 9.86 (2.62-20.9) x 10(-4) WLM(-1), which could be compared to the detriment associated with a unit effective dose. Conclusive dose conversion coefficients in this study ranged from 2.05 (0.55-4.37) to 13.5 (3.59-28.6) mSv WLM(-1), and within this range the discrepancy between dosimetric and epidemiological approaches was included.

Phenotype of apolipoprotein E influences the lipid metabolic response of postmenopausal women to hormone replacement therapy

OBJECTIVES

We investigated whether the phenotype of apolipoprotein E (apo E) would influence the response of postmenopausal Japanese women to hormone replacement therapy (HRT).

METHODS

We measured the plasma levels of lipoprotein and apolipoprotein in 242 postmenopausal women at baseline and again after 12 months of HRT. Patients were divided into three groups according to apo E phenotype: E2+ (E2/2 and E2/3, n=21), E3/3 (n=176), E4+ (E3/4 and E4/4, n=45).

RESULTS

We found that the E4+ group had the highest levels of total and low density lipoprotein (LDL) cholesterol and apolipoprotein B, being significantly higher than in the E2+ group at baseline. The plasma levels of total and LDL cholesterol showed a significant decrease only in the E2+ and E3/3 groups after 12 months of HRT (E2+ group, total cholesterol -8.9% and LDL cholesterol -21.5%; E3/3 group, total cholesterol -2.9% and LDL cholesterol -9.5%). No significant difference in the reduction of total and LDL cholesterol was found in the E4+ group. Other lipid parameters did not differ in the three groups.

CONCLUSIONS

These data show that the apo E phenotype influenced the response of lipid metabolism in postmenopausal women to HRT, especially in the reduction of LDL cholesterol. Therefore, apo E phenotyping may be important in predicting the cholesterol-lowering effect of HRT.

Oral estrogen replacement therapy increases forearm reactive hyperemia accompanied by increases in serum levels of nitric oxide in postmenopausal women

The present study sought to determine the correlation between the vasodilator response of forearm resistance vessels and the circulating levels of nitric oxide (NO) after the administration of oral estrogen for 12 weeks to postmenopausal women. We classified postmenopausal women into two groups: those treated with conjugated equine estrogen (0.625 mg daily) orally for 12 weeks (n = 24) or those who received no treatment (control group, n = 8). Forearm blood flow was measured using strain-gauge plethysmography during hyperemia to evaluate endothelium-dependent vasodilation, and after sublingual nitroglycerin administration to evaluate endothelium-independent vasodilation. Serum levels of nitrite/nitrate (metabolites of NO) and lipid parameters were measured. Basal forearm blood flow, body weight and heart rate were similar in each group. After 12 weeks of estrogen administration, the maximal forearm blood flow response during reactive hyperemia and the serum level of nitrite/nitrate each showed a significant increase from 26.9 +/- 1.9 to 37.9 +/- 3.5 ml/min per 100 ml tissue (p < 0.01), and from 25.2 +/- 2.2 to 37.5 +/- 3.7 mumol/l (p < 0.05), respectively. No increases were seen in controls. The changes in forearm blood flow after sublingual nitroglycerin were similar before and after 12 weeks of estrogen administration. The increase in maximal forearm blood flow with reactive hyperemia was significantly correlated with the increase in nitrite/nitrate in the group administered estrogen (r = 0.48, p < 0.05). There was no significant correlation between maximal forearm blood flow with reactive hyperemia, nor any change in serum lipids, blood pressure or other parameters. In conclusion, the 12-week administration of oral estrogen increased forearm reactive hyperemia in postmenopausal women, probably via an increase in the production of NO.

Evaluation of radiological examination for sensorineural hearing loss

The accuracy of radiological examinations has improved and their diagnostic ability has markedly increased. However, the cost of such examinations has also recently become an issue. In this study, the clinical significance of radiological examinations for sensorineural hearing loss (SNHL) was evaluated and the value of their utilization was reconsidered. A total of 1,276 ears of 724 patients who demonstrated unilateral or bilateral SNHL was studied retrospectively. Findings of radiological examinations such as plain X-ray (X-p), computed tomography (CT) and magnetic resonance imaging (MRI) of the brain or the temporal bone were investigated. Temporal bone X-p was usually performed to rule out acoustic tumors (AT). CT was further performed in 119 patients (16.4%) and MRI in 84 patients (11.6%) in total. The reasons or symptoms for further examination such as CT or MRI were X-p findings or auditory symptoms suspicious for AT or vertigo/dizziness suspicious for intracranial disease. Of five causes with AT, two with a small tumor exhibited normal findings for the internal auditory canal on temporal bone X-p. These small ATs were finally confirmed by MRI. MRI could also detect lacunar infarctions, cerebral atrophy and high jugular bulb which might be related to SNHL. These findings confirmed that MRI is very useful for detecting small ATs and suggested that MRI also reveals cerebral vascular insufficiency in patients with SNHL.

[A case of pulmonary Nocardia farcinica infection in a patient with non-tuberculous mycobacteriosis]

A 64 years old woman without systemic immunological disorders was admitted to our hospital because of a productive cough, low grade fever and bloody sputum. Chest X-ray revealed multiple nodules with calcification, infiltrates and bronchiectasis. Laboratory findings showed mild hypoproteinemia and elevated sedimentation rate. Both Nocardia farcinica and Mycobacterium intracellulare were isolated from the bronchial lavage fluid. Administration of sulfamethoxazole-trimethoprim improved her symptoms. In a recurrent study of bronchial lavage N. farcinica was not isolated, but M. intracellurale was still isolated. We believe that N. farcinica may cause infectious exacerbation of chronic lung disease: non-tuberculous mycobacteriosis and bronchiectasis.

Essential involvement of 12-lipoxygenase in regiospecific andstereospecific oxidation of low density lipoprotein by macrophages

To establish a role of the 12-lipoxygenase on the generation of oxidized low density lipoprotein (LDL) in macrophages that leads to foam cell formation in atherosclerosis, we overexpressed 12-lipoxygenases in a macrophage-like cell line, J774A.1, that does not show intrinsic enzyme activity. When the 12-lipoxygenase-expressing cells were incubated with 400 microg.mL-1 LDL in Dulbecco's modified Eagle's medium at 37 degrees C for 12 h, LDL oxidation, as determined by thiobarbituric acid reactive substance, was markedly increased compared with the mock-transfected cells. Oxygenated products in the modified LDL were examined by HPLC before and after alkaline hydrolysis. Most of the oxygenated derivatives were of an esterified form, and the major product was identified as 13S-hydroxyoctadeca-9Z,11E-dienoic acid. These results clearly demonstrate that esterified fatty acids in LDL are oxygenated by the 12-lipoxygenases expressed in the J774A.1 cells. Furthermore, the oxidized LDL generated by intracellular 12-lipoxygenases was recognized by a scavenger receptor as assessed by macrophage degradation assay.

Growth stimulation and induction of epidermal growth factor receptor by overexpression of cyclooxygenases 1 and 2 in human colon carcinoma cells

There are two isoforms of cyclooxygenase (COX), COX-1 and COX-2. Recent epidemiological and experimental studies indicated a close relationship between COXs and the pathogenesis of colorectal cancer. The purpose of this study was to investigate the possible roles of both isoforms in the proliferation of colon carcinoma cells. A human colon carcinoma cell line, COLO 320DM, was transfected with an eukaryotic expression vector carrying cDNA of either COX-1 or COX-2, the expression of which was driven by a powerful elongation factor-1alpha promoter in pEF-BOS. Both COX-1- and COX-2-expressing cells possessed a similar enzyme activity, 8-10 nmol/10 min per mg protein. Growth rates of both cell lines were stimulated by about 2-fold during a course of culture for 7 days as compared with mock-transfected cells. Although COX-1 and COX-2 are believed to have fundamentally different biological roles, essentially no differences in growth stimulation were observed between the COX-1 and COX-2 overexpressions in our experiments. The reason may be explained by high levels of COX expression, and subtle differences between the both cell lines would be possibly apparent by lower expression levels. The stimulated growth of the COX-transfected cells was accompanied by increased DNA synthesis as assessed by [3H]thymidine incorporation. Furthermore, expression of epidermal growth factor receptor was markedly increased in these cells as examined by reverse transcription-polymerase chain reaction. A COX inhibitor, indomethacin, suppressed the stimulated growth, increased DNA synthesis and induction of epidermal growth factor receptor in COX-1- and COX-2-transfected cells.

Changes in distortion product otoacoustic emissions from ears with Menière's disease

To investigate changes in distortion product otoacoustic emissions (DPOAEs) associated with hearing improvement in ears with Menière's disease, four parameters were studied. These were: DPOAE amplitudes for a moderate (L1/L2 = 65/55 dBSPL) and a high (L1/L2 = 74/64 dBSPL) primary level (65/55-DP and 74/64-DP amplitudes, respectively); maximum level of DPOAE amplitudes in the growth function (maximum DP level); and DPOAE detection threshold (DP threshold) of the growth function. Significant correlations were found between all four parameters and hearing threshold, except for the 65/55-DP amplitude at 1 kHz, and each parameter appeared to reflect the hearing threshold to some extent. However, the changes in the four parameters associated with hearing improvement were somewhat complicated. Changes could not be evaluated due to lack of detection of responses when the hearing thresholds exceeded 50 dBHL. Findings that parameters became detectable, the DP amplitude or the maximum DP level increased significantly, or the DP threshold lowered significantly were classified as "improved" findings. The number of ears with "improved" findings was larger for the maximum DP level or the DP threshold than for the 65/55-DP and 74/64-DP amplitudes in ears with a 10 dB or greater improvement in hearing threshold at the corresponding F2 frequency. Furthermore, a significant decrease in amplitude was found in some ears, although the hearing threshold was not elevated when the 65/55- or 74/64-DP amplitude was used as a parameter. On the other hand, "improved" findings for the maximum DP level or the DP threshold were observed for a relatively large number of ears without a significant change in hearing threshold, and it was thought that small changes in cochlear function which did not lead to changes in hearing threshold were detected by changes in DPOAEs. These findings suggest that parameters determined from the growth function, such as maximum DP level and DP threshold are better indicators for monitoring cochlear function than is DPOAE amplitude for a single primary level, and demonstrate the usefulness of the growth function measurement for monitoring purposes. Furthermore, evaluation by changes in the overall growth function using combined parameters appeared to increase sensitivity in detection of subtle changes in cochlear function. In conclusion, DPOAE measurement can be a useful examination for clinical monitoring of cochlear function in Menière's disease when the growth function is measured.

Sound lateralization and speech discrimination in patients with sensorineural hearing loss

Sound lateralization and speech discrimination abilities are both closely related to central auditory system function. In this study, we investigated the relationship between sound lateralization and speech discrimination in patients with sensorineural hearing loss (SNHL) of unknown aetiology or presbycusis. Interaural intensity difference (IID) and interaural time difference (ITD) discriminations were measured using a self-recording apparatus for dichotic sound presentation, and the means of bilateral maximum scores in speech discrimination tests were calculated. Subjects with normal sound lateralization had good speech discrimination scores above 70%, while those with abnormal sound lateralization had poor scores below 70%. Some patients, however, had good speech discrimination but abnormal sound lateralization. These findings were obtained in both IID and ITD discrimination tests. Furthermore, some subjects could not discriminate ITD, although all could discriminate IID. These findings suggest that sound lateralization ability may be affected more than speech discrimination in SNHL of unknown aetiology or in presbycusis.

Monitoring of response to radiotherapy with fluorine-18 deoxyglucose PET of head and neck squamous cell carcinomas

We examined the usefulness of positron emission tomography (PET) using fluorine-18 deoxyglucose (FDG) in determining the therapeutic effects of irradiation and chemotherapy on head and neck malignant tumors. Twenty-two patients with head and neck lesions who underwent histological examinations were studied. Squamous cell carcinoma was histologically diagnosed in all cases. Sixteen of them underwent radiotherapy with approximately 40 Gy in combination with carboplatin therapy. The remaining 6 patients underwent radiotherapy alone. After these treatments, 11 underwent surgery. For PET study, each patient was injected with intravenous FDG 185-370 MBq. We evaluated the degree of FDG accumulation using scanned images taken 40-55 min after the injection. We measured the standardized uptake value (SUV), a semiquantative evaluation, ROI activity divided by the dosage per weight of each patient. FDG-PET, CT and MRI were performed twice for each patient, before and after treatment. FDG uptake, but not the tumor size in CT or MRI, was significantly reduced in each patient after the treatment. Therefore, our findings have clearly demonstrated that FDG-PET provides for more valuable therapeutic outcomes than conventional imaging such as CT and MRI. FDG-PET should thus provide a new dimension in the management of head and neck malignant tumors.

Anisakidosis: a cause of intestinal obstruction from eating sushi

We report a case of strangulating small bowel obstruction in a 60-yr-old Japanese woman caused by anisakidosis (previously known as anisakiasis). With the increasing popularity of Japanese cuisine such as sushi in the United States, the incidence of anisakidosis is expected to increase. Intestinal anisakidosis can now be treated temporarily, but this condition may cause a serious obstruction afterwards, as evidenced by this particular case. Over 13,500 cases were reviewed in both the Japanese and English literature, and we discuss the prevention of anisakidosis without negatively altering the taste of the raw fish.

Patterns of change in growth function of distortion product otoacoustic emissions in Menière's disease

The patterns of change in the growth function of distortion product otoacoustic emissions (DPOAEs) associated with hearing improvement in six patients with Menière's disease were investigated. The growth functions of 2F1-F2 DPOAEs at F2 frequencies of 1001, 2002 and 4004 Hz (DP-1, DP-2 and DP-4, respectively) were measured with F2 intensities ranging from 70 to 37 dBSPL in 3-dB steps. The F1 intensity was maintained 10 dB higher than the F2 intensity. The growth function was paired with the hearing threshold at the corresponding F2 frequency, and the relationships between changes in DP-1, DP-2 and DP-4 and those in hearing thresholds at 1, 2 and 4 kHz, respectively, were also investigated. The patterns of change in the growth function associated with hearing improvement could be classified into five types. In the first type, the DPOAE growth function became detectable, while the remaining four types were distinguished by combinations of changes in DPOAE amplitudes for lower and higher primary intensities. Multiple parameters, such as maximum amplitude and detection threshold of the growth function, appeared to be required for simple detection and discrimination of these patterns of change. It was also found that the DPOAE growth functions clearly changed in some cases even though the hearing thresholds did not change significantly at the corresponding F2 frequencies. This finding suggests that DPOAE growth function measurement can detect small changes in cochlear function which do not lead to changes in hearing threshold, and has higher sensitivity than pure tone audiometry in monitoring of cochlear function. In conclusion, our findings suggest that measurement of the DPOAE growth function is useful for monitoring cochlear function, and that information on its patterns of change is clinically important and useful.

Temporal bone pathology of a patient with cochlear implant

A 66-year-old man with profound total deafness received a 22-channel cochlear implant. After surgery, his hearing improved and the postoperative course was uneventful except transient vertigo. The patient died of lung cancer after 2.5 years. Twelve hours after death, the temporal bone was harvested for histological and electron microscopic examination. The mastoid air cells were preserved, although a few mucosal folds were present. The Dacron mesh tie had largely been absorbed, but part remained embedded in fibrous tissue. No inflammation was noted in the tympanic cavity or the round window through which the electrodes were inserted. In the cochlea, the scala tympani was filled with fibrous tissue at the site of electrode insertion. The scala media had collapsed, while the organ of Corti and stria vascularis showed degeneration. Osseous spiral bundles and spiral ganglion cells were noted, though reduced in number.

Familial limb-girdle myasthenia with tubular aggregates

Two sisters developed slowly progressive limb-girdle weakness in their childhood. The weakness responded to acetylcholinesterase inhibitors. Repetitive nerve stimulation showed decremental responses and single-fiber electromyography demonstrated increased jitter and blocking. Needle electromyography revealed myopathic changes. Antiacetylcholine receptor antibodies were negative. Histologic examinations demonstrated myopathy with tubular aggregates in the muscle fibers while the neuromuscular junctions appeared normal. They were diagnosed with familial limb-girdle myasthenia. This is the first report of this syndrome with morphologic studies of neuromuscular junctions.

Postnatal development of the internal auditory canal studied by computer-aided three-dimensional reconstruction and measurement

Postnatal development of the internal auditory canal (IAC) was investigated in 20 normal human temporal bones obtained from individuals 1 month to 72 years old. Computer-aided three-dimensional reconstruction and measurement of bones showed that the superior, inferior, anterior, and posterior walls of the IAC lengthen significantly from birth until about 10 years of age, with development mainly attributable to lengthening of the part of the IAC medial to the foramen singulare. The lengths of the part of the IAC lateral to the foramen singulare and of the transverse crest and Bill's bar did not appear to develop postnatally. The IAC diameter increased slightly at the porus for about the first year after birth, but not at the fundus or the middle portion of the canal. This finding was confirmed by studying the shape of the IAC. Postnatal increases in the volume of the IAC followed patterns similar to that of increases in length of studying the shape of the IAC. Postnatal increases in the volume of the IAC followed patterns similar to that of increases in length of the IAC walls. These results show that postnatally the IAC increases significantly in length until about 10 years of age and slightly in diameter until about 1 year of age, especially medial to the foramen singulare. This concentration of growth of the IAC medially implies that its postnatal development is mainly due to growth of the bone around the otic capsule, which has implications for IAC surgery.

[The bactericidal effects of an amphoteric surfactant with ethanol against Mycobacterium tuberculosis]

Bactericidal activities of an amphoteric surfactant (12 w/v% Alkyl diaminoethylglycine hydrochloride, 3 w/v% Alkyl dietylenetriaminoglycole hydrochloride, Nissan Anon #300, Inui Shouji Co., ADG) against Mycobacterium tuberculosis were examined independently or in cooperation with ethanol. The results obtained in the study are as follows: 1. In the treatment with the surfactant diluted with distilled water in one hundredth, the numbers of tubercle bacilli which survived were 500 cfu/0.1 ml after one minute-treatment, and 25 cfu/0.1 ml after ten minutes-treatment. On the other hand, the surfactant containing 23 v/v% ethanol decreased the bacterial numbers to seven cfu/0.1 ml after one minute and less than one cfu/0.1 ml after ten minutes. The numbers of the survived bacilli treated with the surfactant containing 20 v/v% ethanol were 500 cfu/0.1 ml after one minute-treatment, and less than one cfu/0.1 ml after ten minutes though 20 v/v% ethanol alone was ineffective in ten minutes-treatment. 2. The bactericidal activities of the surfactant against tubercle bacilli in sputum samples in which 1.65 x 10(4) cfu/0.1 ml of the organism were contained were also investigated. The numbers of tubercle bacilli which survived were 25 cfu/0.1 ml after one minute-treatment with the surfactant in one fiftieth, two cfu/0.1 ml after five minutes-treatment and one cfu/0.1 ml after ten minutes-treatment. The numbers of the organism treated with the surfactant containing 23 v/v% ethanol were less than one cfu/0.1 ml after five minutes. 3.(ABSTRACT TRUNCATED AT 250 WORDS)

Frequency analysis of evoked otoacoustic emissions in Meniére's disease

Our study was designed to establish a diagnostic significance in Meniére's disease by means of evoked otoacoustic emissions (EOAEs). EOAEs were recorded from patients with Meniére, and the "main frequency" of the emissions, which shows the maximum peak in the frequency spectrum, was examined as a variable. The main frequencies in ears with Meniére ranged mainly from 0.8 kHz to 1.1 kHz and were to be found at lower frequencies than in ears with normal hearing whose range was mainly from 1.0 kHz to 1.6 kHz. Furthermore, in some ears with Meniére, the main frequencies changed from lower to higher after administration of osmotic diuretics such as glycerol or isosorbide. On the basis of these results it was speculated that in ears with Meniére, lower frequency dominant emissions might be elicited by modification of the basilar membrane in endolymphatic hydrops and that the main frequencies might change from lower to higher with reduction of endolymphatic hydrops induced by osmotic diuretics. It was considered that the EOAE testing might be useful for a diagnosis of endolymphatic hydrops in Meniére.

Evoked otoacoustic emissions from ears with idiopathic sudden deafness

Evoked otoacoustic emissions (EOEs) were examined in ears with idiopathic sudden deafness (ISD) at an early stage after onset and were compared with those in ears with long-standing sensorineural hearing losses of unknown etiology (SHLUE). In ears with SHLUE, EOEs were not recordable from ears with a hearing loss exceeding 35 dB at minimum hearing level of 4 audiometric frequencies: 500, 1,000, 2,000 and 4,000 Hz (4 MHL). On the other hand, although 4 MHLs were greater than 35 dB in most of the ears, EOEs could be detected in about one-half of the ears with ISD, and, moreover, the majority of these EOE detectable ears showed a good hearing prognosis in spite of the degree of hearing loss. There was, however, no correlation between EOE threshold and degree of hearing recovery. From these results it seems that EOE testing might be clinically applicable for predicting whether or not hearing loss due to ISD can be recovered.

Frequency analysis of evoked otoacoustic emissions

Evoked otoacoustic emissions (EOEs) were examined in 8 normal hearing ears without spontaneous otoacoustic emissions (SOEs), and the frequency of the first 10 ms after appearance of the EOE response wave was analyzed, dividing it into the first 5 ms half (First half A) and the last 5 ms half (Last half B). In the First half A, the peak frequency of the power spectrum tended to match the stimulus frequency, but in the Last half B, the peak frequency tended to be constant and moreover, it tended to match the frequency at which EOE can best be recorded. These findings suggest that each ear has its own characteristic EOE frequency.

A case of unexpected gallium-67 uptake by sternum in non-Hodgkin's lymphoma with pleuritis

A case of non-Hodgkin's lymphoma with pleural effusion was presented. Pleural effusion is not a common manifestation of this disease and 67Ga-citrate scintigraphy gave the clue for the diagnosis. The possibility of malignant lymphoma should be considered in cases with pleural effusion, and we showed that 67Ga-citrate scintigraphy can be useful in a case with pleural effusion of undetermined cause.

[Clinical comparison of 99mTc-diethylenetriaminepentaacetic acid-human serum albumin (99mTc-HSA-D) and 99mTc-human serum albumin (99mTc-HSA) for cardiac blood pool imaging]

99mTc-HSA-D has been developed as a new blood pool scanning agent. Clinical comparison of 99mTc-HSA-D and 99mTc-HSA was made in 16 cases. The activity concentration of 99mTc in blood was measured during 2 hours after the injection in five cases. 99mTc-HSA-D showed higher concentration compared to 99mTc-HSA with the passage of time. Quantitative analysis of contrast between left ventricle and septum was performed on end diastolic frames of gated images 10 minutes after the injection. There was no obvious difference between 99mTc-HSA-D and 99mTc-HSA. The subjective comparison of detectability of lesions between the two agents was performed on three directional gated images. 99mTc-HSA-D was superior to 99mTc-HSA, because the images of the latter deteriorated with the passage of time. On anterior view images 1 hour after the injection, left ventricle/lung and abdominal aorta/background count ratios were greater for 99mTc-HSA-D in many cases. There was no obvious difference in liver/background and kidney/background count ratios between the two agents. Urinary excretion of 99mTc was considerably lesser for 99mTc-HSA-D. The results indicated that 99mTc-HSA-D was superior to 99mTc-HSA for cardiac blood pool imaging.

Guinea pig complement fixation by tissues from hypocomplementaemic renal diseases

Recently many studies have been done to identify complement pathway activation in renal tissue from patients with renal disease. We examined whether tissues obtained by renal biopsy from such patients would fix guinea pig complement. Nine out of 15 patients with systemic lupus erythematosus (SLE), 4 out of 7 patients with mesangiocapillary glomerulonephritis (MCGN), and 2 out of 7 cases with acute glomerulonephritis (AGN) fixed guinea pig C3. We found that tissues from 5 out of 9 guinea pig C3-positive SLE cases fixed guinea pig C4, while none of the guinea pig C3-positive tissues from patients with MCGN or AGN fixed guinea pig C4. These guinea pig C3-positive renal tissues were further studied for interaction with C4-deficient guinea pig serum, EDTA guinea pig serum, heated guinea pig serum, and EGTA Mg2+ guinea pig serum. The results indicated that activation of both the alternate and classical complement pathways occurred with tissues from patients with SLE, while activation of the alternate pathway occurred with MCGN and AGN. Results for tissues from AGN and MCGN patients indicated the presence of C3 convertase and protease which interacted with guinea pig C3.