Effects of misestimated far-end boundary values on two common lidar inversion solutions

Solutions of the lidar equation in both the Klett [Appl. Opt. 20, 211 (1981)] and the Fernald [Appl. Opt. 23, 652 (1984)] approaches include the effect of errors in the estimated boundary value at the far end. In the present study an attempt is made to formulate the effect of the error in the boundary value on the solution of the lidar equation. Using a modified extinction coefficient, we can simplify and unify the error expression of the lidar inversion solution. From the unified error expression and numerical experiments, we found that (a) in the case of overestimation of the boundary value, the discrepancy between the estimated value and the real value decreases near the lidar more rapidly than in the case of underestimation; and (b) the error for the Fernald solution converges to zero more rapidly than the error for the Klett solution, but the convergence of the Fernald solution sometimes shows oscillatory behavior, whereas the convergence of the Klett solution is always monotonic.

Chronic eosinophilic pneumonia: evolution of chest radiograms and CT features

OBJECTIVE

Our object is to describe and compare the findings on plain chest radiographs and CT scans in patients with chronic eosinophilic pneumonia of varying duration, as judged by their clinical history.

MATERIALS AND METHODS

We retrospectively reviewed the initial chest radiographs and initial CT scans that were obtained before treatment with corticosteroid in 17 patients with pathologically proven or clinically diagnosed chronic eosinophilic pneumonia.

RESULTS

Eleven of the 17 patients showed predominantly peripheral patchy or confluent consolidation with or without ground-glass opacities on chest radiography. Sixteen patients, on the other hand, showed various types of abnormalities with peripheral predominance on CT. The seven patients in whom the initial CT was performed within 1 month after the onset of symptoms had dense confluent consolidation (7/7) with or without ground-glass opacities. When the initial CT was performed 1-2 months after onset of symptoms, inhomogeneous patchy consolidation or nodules (5/7) or ground-glass opacities (2/7) were observed. When the initial CT was performed > 2 months after the onset of symptoms, streaky or band-like opacities (1/3) or lobar atelectasis (1/3) was seen.

CONCLUSION

Patients with chronic eosinophilic pneumonia show an evolution of CT features at varying time intervals after the onset of disease.

Interpretation of subtle interstitial lung abnormalities: conventional versus film-digitized radiography

PURPOSE

To evaluate the reliability of film-digitized radiography in detection of subtle interstitial lung abnormalities.

MATERIALS AND METHODS

The differences in interpretation of conventional screen-film (SF) and film-digitized (FD) radiographs obtained in 80 patients were studied. Forty patients with subtle interstitial lung abnormalities and 40 patients with no lung abnormalities were selected. SF radiographs of all patients were digitized (spatial resolution, 0.175 mm; 2,000 x 2,000 pixels; 10 bits). Five chest radiologists and five residents evaluated the images with a five-level scale of confidence. Results were evaluated with receiver operating characteristic techniques.

RESULTS

For the entire group, no statistically significant differences in performance were found between SF and FD radiographs. Chest radiologists performed better on SF radiographs (P = .003). For residents, no statistically significant differences were observed between the modalities.

CONCLUSION

FD radiographs may be inadequate compared with SF radiographs in the diagnosis of subtle interstitial lung abnormalities.

Heme-heme oxygenase complex: structure and properties of the catalytic site from resonance Raman scattering

The resonance Raman spectra of ferric and ferrous forms of the heme-heme oxygenase (HO) complex (isoform 1) clarify several structural features of the catalytic active site. Isotopic substitution studies of the central iron atom of the heme demonstrate that the line at 218 cm-1 in the ferrous ligand-free form of the complex originates from the iron-histidine stretching mode. The presence of a Raman line at this frequency confirms that the fifth ligand coordinating to the heme is a neutral imidazole from a histidine residue. The modes associated with CO in the carboxy derivative of the ferrous enzyme complex have typical frequencies of histidine-bound heme proteins such as myoglobin. In the ferric form of the complex, at alkaline pH, hydroxide is identified as the bound exogenous ligand, and at neutral pH we infer that water is bound. Thus, the coordination of the heme-HO complex is the same as that in myoglobin. However, in a comparison of the low-frequency vibrational modes in the resonance Raman spectrum of the heme-HO complex to those of myoglobin, the spectra are found to be very different, indicating that the interactions between the heme and its amino acid pocket in these two proteins are quite different. The neutral imidazole may play several important roles in the physiological function of the heme-HO complex.

Image quality of digital chest radiography: evaluation of subtle interstitial lung abnormalities (preliminary study)

To evaluate the image quality of storage phosphor radiography (SR) for diagnosing subtle interstitial lung abnormalities, we studied the differences between conventional screen-film radiography (FR) and SR in 38 patients. Nineteen patients had subtle interstitial lung abnormalities and the others had normal chests. Two formats of hard copies were used for SR; a full-size SR (14 x 14 inches, 0.2-mm pixel size) and a minified SR (9 x 9 inches, 0.13-mm pixel size). Readings were carried out by 14 readers (7 chest radiologists and 7 residents). The area under the receiver operating characteristic curve was used to evaluate the results. For the 14 readers no significant differences in observer performance were observed among the three image sets (FR, full-size SR, minified SR), while for the seven chest radiologists significant differences were observed between FR and the two formats of SR. The best perceptual accuracy was obtained with FR as evaluated by the seven chest radiologists. In conclusion, while overall performance with digital and conventional radiographs was almost the same as far as diagnosing subtle interstitial lung abnormalities, significant differences between FR and SR were found by chest radiologists. Critically important information may be lost in commercially available SR.

Endoluminal ultrasonography in the follow-up of patients with rectal cancer

One principal aim in follow-up after curative surgery for colorectal cancer is to identify recurrent disease at an early and possibly treatable stage. The major problem for patients with rectal carcinoma is local recurrence, which occurs in 3-30 per cent of cases and carries a 5-year survival rate of less than 5 per cent. Since 1989, in addition to digital and sigmoidoscopic examination, endorectal ultrasonography has routinely been used in the follow-up of patients with rectal cancer. Sixty-six patients (40 men) who had undergone attempted radical surgery for mid- and lower-third rectal cancer were included in the study. The mean age was 68 (range 43-87) years. A total of 190 scans were performed, with a mean of 3 (range 1-9) for each patient. Thirteen (20 per cent) of the 66 patients developed local recurrence; in all cases this was suggested by rectal ultrasonography. Digital examination and rigid sigmoidoscopy failed to detect recurrence in three patients. Four detected recurrences were treated radically; the remaining patients received radiotherapy, palliative transanal resection or laser management because of advanced age or refusal to undergo surgery. Six patients were alive a mean of 21 (range 4-50) months after recurrence. Of these six patients, four were free from disease (three had undergone salvage surgery and one radiotherapy). Postoperative rectal ultrasonography can detect some local recurrences at an early treatable stage. The method is more accurate than digital examination and sigmoidoscopy, and should be used as part of a regular follow-up programme.

High-resolution CT and pulmonary function tests in collagen vascular disease: comparison with idiopathic pulmonary fibrosis

To estimate whether the lung abnormalities seen in collagen vascular diseases (CVD) were similar or distinct to those seen in idiopathic pulmonary fibrosis (IPF), and to ascertain whether the extent of the abnormalities on high-resolution CT (HRCT) correlated with pulmonary function, we reviewed HRCT findings and pulmonary function test results of 64 patients with either CVD (n = 55) or IPF (n = 9). Response to corticosteroid treatment was also evaluated in 20 of the 64. High incidence of honeycomb lesion was observed in IPF (9/9, 100%) and in progressive systemic sclerosis (PSS) (11/14, 79%). CVD, except for PSS, had a low incidence of honeycomb lesion (27%). On the other hand, incidence of ground-glass shadow in CVD (47/55, 85%) was the same as that in IPF (8/9, 89%). Diffusing capacity significantly correlated with the extent of all parenchymal abnormalities in all CVD and IPF, with honeycomb lesion in PSS, and with ground-glass shadow or air-space consolidation in CVD except for PSS (r < -0.7, P < 0.001). In all 15 cases in which corticosteroid therapy was effective, no honeycomb lesions were seen. Collagen vascular disease, except for PSS, had a different pattern of disease than IPF. The morphologic changes seen on HRCT correlated well with pulmonary function in CVD.

[Changes in serum lipid and lipoproteins in alloxan-diabetic rats--studies for one year]

Alloxan-diabetic rats were kept on an ordinary or 0.25% cholesterol supplemented diet for up to 12 months, and changes in the serum lipid and lipoprotein levels were examined. The diabetic rats showed IRI levels of 3-5 IU/ml, which were 1/5-1/10 that of the normal rats, and about 10 times higher serum glucose levels than the normal rats. The diabetic rats consumed 1.5-2 fold amounts of diet but their body weights were almost constant. The diabetic rats showed marked hyperlipidemia, especially in the cholesterol and triglyceride levels. The phospholipid level also increased but for a lesser extent and the c/p ratio increased. The serum lipoprotein levels increased in the diabetic rats, 5-10 times in the ordinary diet fed groups and 10-20 times in the cholesterol diet fed groups. Chylomicron, VLDL, IDL and LDL increased but HDL decreased. These changes were more significant in the diabetic rats fed the cholesterol diet. The triglyceride levels in the lipoprotein fractions increased in the diabetic rats, but the increase in cholesterol was more significant and the relative composition ratios of triglyceride decreased. The composition ratios of phospholipids, however, remained almost constant in all the lipoprotein fractions. The increase in IDL, especially cholesterol in the IDL fraction, was remarkable in the diabetic rats. The responsiveness of the diabetic rat VLDL to lipoprotein lipase (release of free fatty acids) was less than a half of that of the normal rat VLDL. In conclusion, the diabetic rats showed an increase in triglyceride but more significant increase in cholesterol in the lipoprotein fractions. These changes in serum lipid and lipoprotein levels and compositions appeared as early as 3 months after the alloxan injection and lasted for 12 months without any progress in the disturbance.

Role of membrane-associated lymphotoxin (mLT) in the killing activity of lymphokine-activated killer (LAK) cells towards various tumour cell lines

Human lymphokine-activated killer (LAK) cells developed by an incubation of peripheral mononuclear cells with IL-2 express the membrane-associated lymphotoxin (LT)-related molecule (mLT). By a further cultivation of mLT expressing (mLT-positive) LAK cells for 24 h without IL-2, mLT disappears (mLT-negative LAK cells). Cytotoxicities of various tumour cell lines by either mLT-positive or -negative LAK cells were compared. Eight out of 12 tumour cell lines, less susceptible to mLT-negative LAK cells than mLT-positive LAK cells, were categorized as group A. Two tumour cells (K562 and Molt-4) had the same susceptibility to both kinds of LAK cells. The others (Daudi and Jurkat) had less susceptibilities only when they were assessed at E:T ratios of less than 5. The four tumour cell lines in the latter two cases, containing K562, Molt-4, Daudi and Jurkat cells, were categorized as group B. The cytotoxicities of group A tumour cells, but not group B tumour cells, by LAK cells were significantly suppressed by the presence of anti-LT antibody. Group A tumour cells had higher LT-binding ability (2.82-16.44 fmol/10(6) cells) than group B tumour cells (less than 1.46 fmol/10(6) cells). Both mLT-positive and -negative LAK cells had similar perforin activities and tumour cell-binding capacities. These results suggest that the mLT-mediated killing mechanism is involved in tumour cell killing by LAK cells. Further, various tumour cell lines can be classified into two large groups according to their susceptibilities to the mLT-mediated killing by LAK cells.

Metastatic pulmonary calcification in patients with hypercalcemia: findings on chest radiographs and CT scans

OBJECTIVE

The objective of this study was to characterize the findings on chest radiographs and CT scans in patients with metastatic pulmonary calcification due to hypercalcemia.

MATERIALS AND METHODS

The chest radiographs and CT scans of seven patients with biopsy-proved metastatic pulmonary calcification were reviewed by two observers. Metastatic calcification was due to chronic renal failure (n = 4), T-cell leukemia (n = 1), multiple endocrine neoplasia type I syndrome (n = 1), and idiopathic hypercalcemia (n = 1).

RESULTS

Numerous nodular opacities measuring 3-10 mm in diameter were seen on the chest radiographs in five cases, and patchy areas of parenchymal opacification were seen in two cases. Calcification of the nodules was evident in two cases. On CT scans, pulmonary nodules were present in all seven cases. These nodules were predominant in the upper lung zone in three cases, were diffuse in three cases, and were predominant in the lower lung zone in one case. Calcification of the nodules was evident on the CT scans in four of the seven cases, and calcification of vessels in the chest wall was evident in six of seven cases. Other findings on CT scans included diffuse areas of ground-glass attenuation (n = 3) and patchy consolidation (n = 2).

CONCLUSION

Numerous small nodules are the most common finding on the chest radiographs of patients with metastatic pulmonary calcification. The calcific nature of the nodules is seldom obvious, however. Pulmonary nodules are also the most common finding on CT scans, where the calcific nature of the nodules is more readily apparent. Additionally, calcification is often seen in the vessels of the chest wall on CT scans. The combination of calcified nodules and calcified vessels in the chest wall on CT scans may be characteristic.

Improved method for the analysis of ascorbic acid in plasma by high-performance liquid chromatography with electrochemical detection

We improved the analytical method for the detection of ascorbic acid in plasma by high-performance liquid chromatography (HPLC) with an electrochemical detector (ECD) to be more selective and rapid than the protocol previously used. Main improvements are as follows. Applied potential of ECD to obtain the maximal response for ascorbic acid was +450 mV versus Ag/AgCl, but it was reduced to +350 mV. In that condition, uric acid did not respond to ECD, and only ascorbic acid was detected. EDTA contained in sample extraction/stabilizing solution gave the peak after the ascorbic acid. The addition of EDTA (0.2 mM) to the mobile phase eliminated the EDTA peak. These two improvements gave the chromatogram in which the peak that appeared from the plasma sample was only ascorbic acid, and shorten the sample run time. Ascorbic acid in plasma was unstable even though the plasma was treated with methanol/EDTA: it decreased from 1.5 h at 4 degrees C. However, the treated sample, which was placed at -14 degrees C until the analysis was performed, gave the reliable ascorbic acid value at least up to 6 h. The data obtained from the HPLC-ECD method was consistent with those from the hydrazine method.

Decreased susceptibility of glycated very low density lipoproteins to lipoprotein lipase in vitro and prevention by glutathione

In vitro glycation of very low density lipoprotein (VLDL) reduced the susceptibility to lipoprotein lipase (LPL) as the level of glycation increased. Addition of reduced glutathione to an incubation medium of serum and glucose interfered with glycation of serum proteins when the concentration of reduced glutathione was higher than 10 mM. At concentrations higher than 25 mM, it also significantly prevented the glycation induced reduction of fatty acid releases from VLDL by LPL. There were no such effects on glycation of serum protein and the fatty acid release from the addition of aminoguanidine. By contrast, addition of D-lysine enhanced glycation of serum proteins by glucose and further decreased fatty acid release from VLDL by LPL. From these results, it is suggested that glycation of VLDL decreases the susceptibility of VLDL to LPL. Delayed catabolism of VLDL in diabetic patients is considered partly caused by glycation of apoproteins, which renders VLDL less sensitive to LPL, in addition to the decreased LPL activity in diabetes mellitus.

Effect of beta-carotene on spontaneous and X-ray-induced chromosomal damage in bone marrow cells of mice

The effect of beta-carotene on spontaneous and X-ray-induced chromosomal damage in bone marrow cells of mice was studied. As a source of beta-carotene, dried Dunaliella bardawil (containing 6% beta-carotene) or oil suspension of Dunaliella beta-carotene was used. In Experiment 1, mice were given a basal diet, a 0.5% Dunaliella diet, or a 4% Dunaliella diet for four weeks. In Experiment 2, mice were given an oil suspension of Dunaliella beta-carotene (300 mg/kg body wt) by gavage for seven days while being fed a fat-rich diet. After beta-carotene treatment for the indicated time, spontaneous and X-ray (0.3 Gy, whole-body)-induced chromosomal damage in bone marrow cells was evaluated in terms of the percentages of micronucleated reticulocytes in their peripheral blood. The beta-carotene treatment slightly lowered the spontaneous and X-ray-induced chromosomal damage in bone marrow cells. Despite the higher doses of beta-carotene, the concentrations of beta-carotene in bone marrow, liver, and serum were much lower than those of vitamin E. In addition, the beta-carotene treatment markedly lowered the concentration of vitamin E in the tissues.

Preoperative embolization for paraganglioma

We have applied a new method of preoperative embolization to an intravagal and to carotid body paraganglioma, using estrogen dissolved in absolute alcohol and polyvinyl alcohol particles, which diffusely embolizes vessels from capillaries to main feeders. Total resection of the tumors after embolization was successively performed without postoperative complications; total blood loss was 205 and 130 ml, respectively, and the surgical time was approximately 3 hours in both cases. The technique, characteristics, and advantages of this method are discussed.

Acute myelopathy and cerebellar signs associated with uveitis with positive serum and cerebrospinal fluid antibodies to HTLV-I

A 55-year-old man was admitted because of weakness in the legs of a few days duration. Neurological examination revealed paraparesis, ataxia of the left limbs, superficial hypoesthesia below the T-10 dermatome level and urinary retention. The antibody titers to human T-lymphotropic virus type I (HTLV-I) were x640 in the serum and x16 in the cerebrospinal fluid (CSF). The HTLV-I gag proteins, p19, p24, p46 and p53 were identified by Western blotting analysis of the serum and CSF. The CSF contained 691 white cells/c.mm; protein, 260 mg/dl; IgG, 84 mg/dl; and IgG index, 2.49. Although the paraparesis and urinary retention disappeared within 10 days, he developed right uveitis which responded well to corticosteroid treatment. With improvement of the sensory impairment, cerebellar signs and CSF pleocytosis as well as uveitis, he was discharged eight weeks after admission. HTLV-I uveitis is a recently established disease entity. The case emphasizes the need to test blood and CSF for HTLV-I antibodies if patients developed myelopathy and cerebellar signs of acute onset, especially when associated with uveitis.

Extracorporeal shock wave lithotripsy using the Dornier MPL 9000 lithotriptor

336 patients with urinary calculi were treated between June 1988 and October 1991 with extracorporeal shock wave lithotripsy using the Dornier MPL 9000 lithotriptor. Of 352 renal units (a kidney and its ureter), 286 had renal stones, 62 had ureteral stones and 10 had both. There were radiolucent stones in 6 units. The complete disintegration rate was 94%. The mean number of shock waves was 2,973, the range being from 300 to 16,131. In 310 of 447 (64%) sessions, treatment was done without any anesthesia. The rate of complete removal was 67.3% 3 months after the last treatment. Only 11 patients required supplementary treatment consisting of percutaneous nephrolithotripsy and transurethral lithotripsy. There were no severe complications except subcapsular hematomas observed in 2 patients. The Dornier MPL 9000 is a useful lithotriptor for the treatment of urinary calculi, except staghorn calculi.

Development of atherosclerosis in alloxan diabetic rats

Rats with alloxan-induced diabetes developed severe atherosclerotic lesions when they were maintained on a 0.25% cholesterol diet for one year. The atheromatous changes developed at the aortic arch, appeared as early as 3 months after the start of the experiment, and increased thereafter. The diabetic rats also developed atherosclerosis when they were fed standard rat chow, but the area of the atheromatous lesion was about one tenth of that in rats fed the high-cholesterol diet. Normal rats did not develop atherosclerosis even when fed the high-cholesterol diet for one year. The alloxan diabetic rats showed no increase in body weight, but developed serum glucose levels as high as 600-800 mg/dl as well as high serum cholesterol levels and lower serum HDL-cholesterol levels. The development of atherosclerosis in these rats was significantly related to an increase in the serum cholesterol/phospholipid ratio, the atherogenic index (TC-HDLC/HDLC), and the serum total cholesterol level, but was not related to the serum glucose, HDL-cholesterol, triglyceride, or lipid peroxide levels. These relationships were found as early as B-16 weeks after the start of the experiment. These data suggest that the serum cholesterol/phospholipid ratio, the atherogenic index, and the total cholesterol level are important risk factors for the development of atherosclerosis in rats with alloxan diabetes.

Sequential promotion of normal and leukemic hemopoiesis by recombinant human granulocyte colony-stimulating factor during the course of myelodysplastic syndrome

A 48-year-old man developed refractory anemia with excess of blasts in transformation. Complete response was achieved by low-dose ara-C therapy, but he relapsed 15 months later, with pancytopenia and 13.0% myeloblasts in normocellular marrow. He was treated unsuccessfully with prednisolone, metenolone, and 1-alpha-hydroxyvitamin D3 for 8 weeks. He then developed life-threatening pneumonia and was treated with recombinant human granulocyte colony-stimulating factor (rhG-CSF Filgrastim; 125 micrograms/day s.c.). The pneumonia resolved and, interestingly, he achieved a partial response, with normal blood cell counts and only a few dysmyelopoietic cells in the marrow. However, thrombocytopenia progressed when rhG-CSF administration was tapered. When the dose was increased again, leukemic blasts were found to proliferate. When rhG-CSF was discontinued, blasts rapidly decreased in the peripheral blood. Chromosomal analysis revealed a complex abnormality during the first relapse, a normal 46,XY karyotype during the partial response, and recurrence of the same complex abnormality during leukemic transformation. The stimulation index of marrow mononuclear cells cultured with rhG-CSF increased with disease progression. These findings suggest that rhG-CSF initially stimulated the selective proliferation of normal hemopoietic cells, but the evolution or selection of a leukemic clone responsive to rhG-CSF appears to have occurred subsequently.

Membrane-associated lymphotoxin expression and functional analysis of lymphokine-activated killer cells derived from tumor-infiltrating lymphocytes

The expression of a membrane-associated lymphotoxin molecule (mLT) on lymphokine-activated killer (LAK) cells obtained from 18 patients with malignant tumors and its role in the tumor cell killing mechanisms were investigated. LAK cells from tumor-infiltrating lymphocytes (TIL-LAK cells) were mainly composed of CD3-positive cells, whereas LAK cells from peripheral blood lymphocytes (PBL-LAK cells) were mainly composed of CD16- and CD56-positive cells. However, mLT was found to be expressed on TIL-LAK cells as well as PBL-LAK cells. The degree of mLT expression correlated with the killing activity of LAK cells towards L929 cells (r = 0.806, P < 0.01, n = 15), but not with that towards Daudi or K562 cells. Although the degree of mLT expression correlated with the amount of secreted lymphotoxin (LT) in the supernatant of LAK cell culture, the secreted LT itself could not account for the tumor cell killing activity of LAK cells. Polyclonal rabbit anti-LT antibody partially inhibited the killing activities of LAK cells towards L929 cells and this inhibition was found in the combination of autologous tumor cells and PBL-LAK cells. These findings suggest the possibility that the mLT-related cytotoxicity is involved in the tumor cell killing mechanisms of TIL-LAK cells as well as PBL-LAK cells.

[The effects of the treatment for acute rejection with OKT3 monoclonal antibody treatment on the long-term results of cadaveric kidney transplantation]

Although the efficacy of OKT3 monoclonal antibody (OKT3) upon the steroid resistant rejection is well known, its beneficial effect on long-term result of kidney transplantation has not yet been well examined in Japan. A retrospective group study was performed to analyze the effect of OKT3 on the cadaver kidney allograft. Between September 1987 and October 1990, a total of 77 patients from four different hospitals were classified into 2 groups. Thirty-four patients from 2 hospitals were entered OKT3 therapy group and 43 patients from the other hospitals were entered steroid therapy group. Initial immunosuppression comprised low-dose cyclosporine (6 mg/kg), steroid and antilymphocyte globulin in both groups. In OKT3 therapy group, acute rejection episodes those were considered steroid resistant were observed in 7 patients. They were treated with OKT3 monoclonal antibody. Of the seven patients, six recovered normal renal function. The mild rejection in OKT3 therapy group was treated with high-dose steroid. Minimal follow-up was 2 years. The 2-year graft survival was 82.4% in OKT3 therapy group and 74.4% in steroid therapy group. Although the improvement on the 2 year graft survival with OKT3 treatment was 8%, the difference between two groups was not statistically significant.

Focal organizing pneumonia: CT appearance

PURPOSE

To clarify the computed tomographic (CT) features of focal organizing pneumonia.

MATERIALS AND METHODS

The authors retrospectively studied CT scans of 18 patients with histologically proved focal organizing pneumonia. Chest radiographs in all 18 patients suggested bronchogenic carcinoma.

RESULTS

Seventeen of the 18 lesions (94%) had an irregular margin, 10 (56%) had satellite lesions, nine (50%) had a pleural tag, and nine (50%) had an air bronchogram. The pneumonia could be classified into three types: Type A (n = 5) was a small round mass (pleural tag, n = 4). Type B (n = 7) was an oval mass with broad contact with the pleura (satellite lesions and convergence of peripheral vessels, n = 6). Type C (n = 6) was an oval mass along the bronchovascular bundle (satellite lesions, n = 3; pleural tag, n = 4).

CONCLUSION

The CT features of focal organizing pneumonia show wide variation, and some type B and C lesions are suggestive of benign lesions. However, other lesions may be difficult to differentiate from bronchogenic carcinoma even with CT.

Ultrastructural arrangement of collagen fibrils in the rat facial nerve

We studied the collagen fibril arrangement in the connective tissue sheaths (epineurium, perineurium, and endoneurium) of the intratemporal and extra-temporal portion of the rat facial nerve by transmission electron microscopy after fixing the nerves with tannic acid, and by scanning electron microscopy after digesting cellular elements by sodium hydroxide treatment. These studies revealed that the epineurium consists of thick bundles of collagen fibrils and a coarse meshwork of collagen fibrils, the perineurium consists of a lacework sheet of bundles of collagen fibrils, and the endoneurium consists of a meshwork of fine collagen fibrils in the inner layer and of longitudinally oriented bundles of collagen fibrils in the outer layer. There was little difference in the three-dimensional organization of collagen fibrils between the extra-temporal segment and vertical and horizontal segments of the facial nerve. However, the facial nerve lost the epineurium and perineurium in the central portion of the horizontal segment near the geniculate ganglion and in the labyrinthine portion, i.e. the proximal portion of the intratemporal segment. In these segments, the endoneurium consisted of a meshwork of fine collagen fibrils.

In vitro degradation of very low density lipoprotein from diabetic patients by lipoprotein lipase

Fatty acid release by incubation with lipoprotein lipase (LPL) in vitro from very low density lipoproteins (VLDL) obtained from diabetic patients was low compared with that from healthy subjects, though the compositions were similar in both VLDL. Percentages of the large size VLDL decreased and those of the small size VLDL increased after the incubation with LPL. At the same time, on polyacrylamide gel disk electrophoresis, the smaller catabolic products from these VLDL appeared at a similar position to that of low density lipoproteins (LDL) and at the running front where high density lipoproteins (HDL) had migrated. The amount of the small size VLDL and the LDL-like lipoproteins produced from diabetic VLDL were less than those from normal VLDL and inversely correlated with the percent decrease of the large original size VLDL. This fact suggests that VLDL from diabetic patients are poor substrates for LPL compared with normal VLDL.

Possible role of Na+ influx in phorbol ester-induced down-regulation of protein kinase C in HL60 cells

Amiloride, an inhibitor of Na+/H+ exchange, inhibited down-regulation of protein kinase C in HL60 cells induced by tumor-promoting phorbol ester in dose-dependent manner judging from immunoblot analysis. This inhibition was observed with regard to type I (gamma), type II (beta), and type III (alpha) isozymes of protein kinase C. On the other hand, monensin, a Na+ ionophore, accelerated the down-regulation of protein kinase C induced by phorbol ester. When we examined 22Na+ uptake by HL60 cells, the higher uptake was observed after stimulation with phorbol ester compared to the control cells and this 22Na+ uptake was strongly inhibited by the addition of amiloride. However, monensin further stimulated the 22Na+ uptake observed in phorbol ester-treated cells. These data suggest that the increase in intracellular Na+ concentration may be one of the triggers for the induction of down regulation of protein kinase C.

The lectin concanavalin A stimulates a protein-tyrosine kinase p72syk in peripheral blood lymphocytes

We report that the activation of porcine peripheral blood lymphocytes (PBL) by lectin concanavalin A (Con A) led to the increase in tyrosine phosphorylation on 84-, 72-, 55-, 40-, and 33-kDa proteins. A non-receptor protein-tyrosine kinase (PTK), p72syk (Taniguchi et al. (1991) J. Biol. Chem. 266, 15790-15796), was detected in PBL around 0.1% of total protein and distributed in both particulate and cytosolic fractions. Furthermore, Con A induced a rapid activation of p72syk within 1 min in a manner similar to the time course of Con A-induced protein-tyrosine phosphorylation. These results suggest that p72syk plays a certain role in the activation of PBL and that p72syk may be one of the major non-receptor PTKs in T cells as well as in B cells.

[Evaluation and problems of ultracentrifugal technique for separation and analysis of serum lipoproteins: comparison with other analytical methods]

An ultracentrifugal technique for separating and analyzing serum lipoproteins was evaluated in comparison with analyses by electrophoresis using agarose-gel and polyacrylamide-gel. In general, the percent of pre beta- and beta-lipoproteins in electrophoresis was estimated higher than the percent of VLDL and LDL in ultracentrifugal method, while the percentage of alpha-lipoprotein in the former was estimated lower than that of HDL in the latter. In cases with abnormal lipoproteinemias, various discrepancies arose between the methods. For examples, pre beta- and beta-lipoproteins were estimated too high by the analyses with electrophoresis. The cholesterol content in HDL decreases in hypertriglyceridemia accompanied by an increase in triglyceride content. Therefore, when HDL cholesterol is determined by a polyanion method to assess the net HDL concentration in such cases, it is estimated to be low. Such errors are not only found in the determination of HDL cholesterol, but also in apoproteins in liver cirrhosis, because the composition of HDL apoprotein is markedly altered. Since the heterogeneity of lipoproteins separated by ultracentrifugation is characteristic in hereditary disorders of lipoproteins such as LCAT deficiency, the centrifugal technique is essential for lipoprotein analysis in such disorders. The disadvantages in ultracentrifugation are cross-contaminations among fractions, and removals of lipids and apoproteins from lipoprotein particles. Apo A-I and E proteins, and phospholipids were removed from the particles more rapidly than other components. From the results of repeated ultracentrifugation of HDL, 3% of apo A-I was estimated to be lost from the HDL during the centrifuge procedure.

Inhibition of homologous complement activation by the heat-stable antigen

The murine heat-stable antigen (HSAg) is of particular interest due to its unique tissue distribution. HSAg is expressed on most thymocytes, bone marrow cells, immature B cells, and erythrocytes, but not on peripheral T and mature B cells. Although HSAg has been thought to be a differentiation antigen, its actual biological significance remains unknown except for the HSAg on antigen presenting cells. Recently, a new rat anti-HSAg mAb, R13, has been developed. Here it has been found that the mouse complement activation on mouse erythrocytes, but not the human, guinea pig or rabbit complement activations, was enhanced in the presence of the Fab fragment of R13. Affinity-purified HSAg derived from mouse erythrocytes could be passively incorporated into rabbit erythrocytes because of its molecular characteristic of glycosylphosphatidyl inositol-anchored protein. Mouse complement activation, but not guinea pig complement activation, was partially suppressed on the HSAg-incorporated rabbit erythrocytes. These findings suggest that HSAg has a homologous complement regulating activity.

Mechanism of gravity-dependent atelectasis. Analysis by nonradioactive xenon-enhanced dynamic computed tomography

RATIONALE AND OBJECTIVES

The physiologic mechanism of gravity-dependent atelectasis (GDA), a common finding identified during anesthesia, is not well understood. The purpose of this study was to determine whether an inherent reduction in alveolar volume or a reduction in alveolar ventilation is the more important causative factor for the development of GDA in an experimental animal model.

METHODS

After uniform reduction of lung volume in ten rabbits by artificially induced pneumoperitoneum, dynamic inhalation computed tomography (CT) was performed using 50% nonradioactive xenon in oxygen. Time-CT attenuation value curves were fitted to an exponential function, CT value = a - b x e(-kt), and K value, which is proportional to the alveolar ventilation/alveolar volume ratio, was calculated by regression analysis.

RESULTS

Gravity-dependent atelectasis occurred only in 5 of 10 rabbits. In this group, K values in the dorsal regions increased before the appearance of GDA. No significant change in K values in the ventral regions was observed.

CONCLUSION

One mechanism of GDA may be a preferential reduction in alveolar volume without small airway collapse rather than alveolar volume loss secondary to decreased ventilation.

Metastatic pulmonary calcification: early detection by high-resolution CT

A 41-year-old man with a renal transplant was admitted with cough, fever, and dyspnea. Although chest radiography was normal, high-resolution CT demonstrated small hazy round opacities in the centrilobular regions throughout both lungs. The biopsy specimen revealed metastatic calcification in the alveolar septa and the walls of the bronchioles and arterioles. High-resolution CT may be useful for the early detection of metastatic pulmonary calcification when plain radiography is negative and therapy has the potential to reverse the process.

Interpretation of subtle interstitial lung abnormalities: conventional versus storage phosphor radiography

To evaluate the reliability of storage phosphor radiography (SR) in diagnosis of subtle interstitial lung abnormalities, the differences among radiologists in interpreting conventional screen-film radiographs and full-size and minified SR images obtained in 80 patients were studied. Forty patients had subtle interstitial lung abnormalities and 40 had no lung abnormalities. Seven chest radiologists and seven residents evaluated the images by using a five-point presence of abnormality scale. Results were evaluated with receiver operating characteristic technique. For all observers, no significant differences were observed among the three image types. For the chest radiologists, significant differences were observed between conventional radiographs and the two SR formats (P < .01). Furthermore, perceptual accuracy was best with conventional radiographs evaluated by chest radiologists. Overall performance with SR and conventional radiography was identical for diagnosis of abnormalities, but detection performance was significantly dependent on observer experience (P < .01 for chest radiologists and P > .01 for residents). For chest radiologists, critically important information may be lost with commercially available SR.

Actions of benzalkonium chloride as a potent depressant at the neuromuscular junction

Benzalkonium chloride (BA), a positively charged surface active agent, applied (> 10 nM) in the superfusing solution, produced a concentration-dependent reduction in the amplitude of both evoked endplate potentials (EPPs) and spontaneous miniature EPPs of the frog. Voltage-clamped endplate currents (EPCs) and spontaneous miniature endplate currents (MEPCs) were also diminished in amplitude, in the presence of BA (50-140 nM), whereas their time-course and reversal potential were not obviously affected. No significant change due to the addition of 50 nM BA was observed in apparent properties of the ACh channel estimated from ACh-induced current fluctuations. In the relationship between the amplitude of ACh potentials and the net charge for iontophoretic pulses at a single junction, the principal pattern of action of BA (30-60 nM) appeared to be a parallel shift to the right. At concentrations greater than about 1 microM, BA slightly increased the resting input conductance of the non-synaptic muscle fibre membrane. It was suggested that this increase was attributable to a slight increase in Cl ion conductance of the non-synaptic membrane. These results indicate that BA effectively blocked neuromuscular transmission, acting as an ACh receptor antagonist at smaller concentrations and as a more potent blocker that acts through multiple sites at greater concentrations.

Lipid transfer particle in the hemolymph of the American cockroach: evidence for its capacity to transfer hydrocarbons between lipophorin particles

A lipid transfer particle (LTP) was isolated and purified from the hemolymph of the adult male American cockroach, Periplaneta americana, essentially according to the method previously developed for the purification of LTP from locust hemolymph. Fast protein liquid chromatography (FPLC) on a Mono Q column was used as the additional step to obtain pure LTP. The electron micrograph of purified cockroach LTP exhibited an unusual and asymmetric shape essentially similar to that reported for Manduca sexta LTP (Ryan et al. 1990. J. Lipid Res. 31:871-879). The cockroach LTP was also found to be basically similar to that of M. sexta and locust in terms of subunit structure and lipid composition, although there were significant differences particularly in the contents of hydrocarbons and diacylglycerol. A simple method for assaying LTP activity was developed, based on the finding that cockroach LTP can catalyze the transfer of labeled hydrocarbons (or diacylglycerol) from labeled high density lipophorin (HDLp) bound with a transfer membrane (Immoblion) to unlabeled HDLp dissolved in saline. This finding reveals that cockroach LTP has the capacity to transfer and/or exchange lipids between lipophorin particles with the same density. It was also demonstrated that cockroach LTP has the capacity to catalyze the transfer and/or exchange of hydrocarbons, in addition to diacylglycerol, between cockroach HDLp and locust low density lipophorin (LDLp).

Expression of perforin and membrane-bound lymphotoxin (tumor necrosis factor-beta) in virus-specific CD4+ human cytotoxic T-cell clones

In an attempt to clarify the mechanisms of cytotoxicity mediated by CD4+ cytotoxic T lymphocytes (CTL), the expression of perforin and membrane-bound lymphotoxin (LT) (tumor necrosis factor-beta) in herpes simplex virus (HSV)-specific CD4+ human cytotoxic and noncytotoxic T-cell clones was examined. Three HSV-specific CD4+ human CTL clones that showed HLA-DR-restricted cytotoxicity and proliferative response were established. The cytotoxicity of these clones in 5-hour 51Cr release assays was found to be mediated by the directional target cell lysis and not by the release of cytotoxic soluble factors, ie, "innocent bystander" killing. Northern blot analysis showed that messenger RNAs for perforin and LT, which were both considered to be important mediators for cytotoxicity of CD8+ CTL and natural killer cells, were abundantly expressed in HSV-specific CD4+ CTL clones. Expression of perforin in the cytoplasm of CD4+ CTL clones was also detected by immunohistochemical staining using a monoclonal antibody against perforin. In addition, LT bound to the cell surface of CD4+ CTL clones was detected by flow cytometry. In contrast, little or no expression of perforin and LT was detected in three HSV-specific CD4+ noncytotoxic T-cell clones. Although the cytotoxicity mediated by lymphokine-activated killer cells was partly inhibited by addition of anti-LT antibody, it did not show any effect on the cytotoxicity of HSV-specific CD4+ CTL clones. In addition, it was found that cytotoxicity mediated by these CD4+ CTL clones was Ca2(+)-dependent. These data thus suggest that perforin and membrane-bound LT are both expressed in HSV-specific CD4+ CTL, although perforin might be the more important mediator in short-term culture.

Peripherally administered serotonin induces hyperglucagonemia in mice

Peripherally administered serotonin (5-HT) induced a marked increase in the plasma glucagon level in mice. The hyperglucagonemic effects of 5-HT were completely antagonized by methysergide, ketanserin and ritanserin which have a high affinity for 5-HT2 receptors. However, the 5-HT3 receptor antagonist ICS 205-930 and MDL 72222 were without effect. These findings suggest that the activation of the peripheral 5-HT2 receptor induces the increase in plasma glucagon level and that these receptors may play a role in the release of glucagon.

[An arch and ascending replacement for aortic arch dissection by "separate hypothermia" retrograde cerebral perfusion]

We have developed a new technique of cerebral perfusion during operations on the aortic arch. The concept of this technique is as follows. A retrograde cerebral perfusion provides a relative long time to perform the distal aortic repair, and simplifies the operation. To avoid the disadvantages by deep hypothermia, we perfused from SVC cannula with blood cooled at 10-15 degrees C, from femoral artery with blood cooled at 20-26 degrees C. A successful case using this method is as follows. A 68-year-old man was referred to our hospital for aortic arch dissection. He underwent an operation 4 weeks after onset. Graft replacement of ascending aorta and aortic arch was performed under this method. We perfused blood from SVC cannula at an internal jugular vein pressure of 30 cmH2O, and SVC perfusion flow was 600 cc/min. By this separate hypothermia perfusion, the nasopharyngeal temperature is maintained about 15 degrees C, the rectal temperature is maintained 22-24 degrees C. The duration of cerebral perfusion from SVC cannula was 125 min, but prolonged emergence from anesthesia and neurological deficit were not seen.

Inhibitory effect of mitoxantrone on activity of protein kinase C and growth of HL60 cells

Mitoxantrone, a new anthraquinone, showed inhibitory an effect on protein kinase C (PKC) activity. Its IC50 value was 4.4 micrograms/ml (8.5 microM), which is much lower than those of the well-known anthracyclines daunorubicin and doxorubicin, the IC50 values of which are more than 100 micrograms/ml (> 170 microM). Kinetic studies demonstrated that mitoxantrone inhibited PKC in a competitive manner with respect to histone H1, and its Ki value was 6.3 microM (Ki values of daunorubicin and doxorubicin were 0.89 and 0.15 mM, respectively), and in a non-competitive manner with respect to phosphatidylserine and ATP. Inhibition of phosphorylation by mitoxantrone was observed with various substrates including S6 peptide, myelin basic protein and its peptide substrate derived from the amino-terminal region. Their IC50 values were 0.49 microgram/ml (0.95 microM), 1.8 micrograms/ml (3.5 microM), and 0.82 microgram/ml (1.6 microM), respectively. Mitoxantrone did not markedly inhibit the activity of cyclic AMP-dependent protein kinase, casein kinase I or casein kinase II, at concentrations of less than 10 micrograms/ml. On the other hand, brief exposure (5 min) of HL60 cells to mitoxantrone caused the inhibition of cell growth with an IC50 value of 52 ng/ml (0.1 microM). In HL60 cells, most of the PKC activity (about 90%) was detected in the cytosolic fraction. When HL60 cells exposed to 10 micrograms/ml mitoxantrone for 5 min were observed with fluorescence microscopy, the fluorescence elicited from mitoxantrone was detected in the extranuclear area. These results indicated that mitoxantrone is a potent inhibitor of PKC, and this inhibition may be one of the mechanisms of antitumor activity of mitoxantrone.

CT appearance of pulmonary tuberculosis in diabetic and immunocompromised patients: comparison with patients who had no underlying disease

OBJECTIVE

It has been stated, but not adequately assessed, that pulmonary tuberculosis in diabetic or immunocompromised patients often has an atypical pattern and distribution. To evaluate the CT features of pulmonary tuberculosis in diabetic or immunocompromised patients compared with patients without underlying disease, we performed this retrospective study.

MATERIALS AND METHODS

We reviewed conventional CT scans (n = 100) and high-resolution CT scans (n = 16) of the chest in 110 adult patients with active postprimary tuberculosis. Seventy-one patients had no underlying disease, 31 had diabetes mellitus, and eight were immunocompromised.

RESULTS

In patients who had no underlying disease, 44 had nodular opacities, 11 had consolidation, and 13 had consolidation with associated loss of volume. Characteristic features of tuberculosis in this group of patients included segmental distribution (97%), satellite lesions (93%), single cavity within any given lesion (95%), and tendency toward architectural distortion and loss of volume. In diabetic and immunocompromised patients, 15 had nodular opacities, seven had consolidation, and 15 had consolidation with associated loss of volume. Diabetic and immunocompromised patients had a high prevalence of nonsegmental distribution (30%) and multiple small cavities within any given lesion (44%). Unusual localization of tuberculosis, including disease confined to the basal segments of the lower lobes, anterior segment of the upper lobes, or right middle lobe, occurred equally in both groups (17% and 18%).

CONCLUSION

We conclude that diabetic and immunocompromised patients have a higher prevalence of multiple cavities within any given lesion (p < .01) and of nonsegmental distribution (p < .01) than do patients without underlying disease.

CT findings in "pseudoalveolar" sarcoidosis

To determine the specific high resolution CT (HRCT) features for "pseudoalveolar" sarcoidosis, we reviewed HRCT of 10 patients with pathologically proven sarcoidosis. On HRCT the lesions of pseudoalveolar sarcoidosis were shown as homogeneous or inhomogeneous opacities 1-4 cm in diameter located either along the bronchovascular bundles or in the lung periphery adjacent to the pleural surface. The margin was irregular, and numerous nodules 1-2 mm in diameter were observed in the surrounding lung. Air bronchograms were observed in 6 patients. In addition to these lesions, other CT abnormalities such as nodules, groundglass opacities, thickened bronchovascular bundles, and interlobular septa were found in all 10 cases. Good response of pseudoalveolar sarcoid lesions to administration of corticosteroid was observed in all three cases in which follow-up CT was available.

[Adverse reactions to low osmolar iodine contrast media (second report)]

From January to December 1990, we performed a prospective survey of adverse reactions to contrast media at two different institutes of Juntendo University. We collected a total of 4555 case sheets during the period. The radiological procedures we investigated were computed tomography, intravenous urography, arteriography, venography and myelography. Low osmolar iodine contrast medium was used almost exclusively (except for five cases). The overall incidence of adverse reactions was 7.0%, and there were no severe or fatal reactions. The incidence of adverse reactions was higher in females (8.5%) than in males (6.1%). The incidence of adverse reactions increased according to the dose of contrast medium, especially when more than 101 ml was injected. Intra-arterial injection caused adverse reactions most often, followed by regular intravenous injections, followed by bolus intravenous injections. Adverse reactions occurred most often during injection. The next occurred in 5 minutes after injection, and then, 5-10 minutes after the injection of contrast medium. The incidence of adverse reactions was higher in patients with a history of allergy or previous reactions. Allergic adverse reactions were observed at a higher frequency. Pretesting was performed in 56.7% of the cases.

Purification of the murine heat-stable antigen from erythrocytes

The rat anti-mouse erythrocyte (MRBC) monoclonal antibody (mAb), R13, has been developed. The MRBC membrane protein recognized by R13 (R13-Ag) can be purified by loading the butanol-extracted MRBC membrane solution on a R13-conjugated Cellulofine column in the presence of 0.1% CHAPS followed by elution with 1% CHAPS. The amino acid sequence of the affinity-purified R13-Ag corresponded to that predicted from the cDNA for the murine heat-stable antigen. It was revealed that the actual heat-stable antigen was composed of 27 amino acids.

Intestinal type alkaline phosphatase hyperphosphatasemia associated with liver cirrhosis

Hyperphosphatasemia due to increased intestinal type serum alkaline phosphatase was noted in a 48-year-old male who had asymptomatic liver cirrhosis. The alkaline phosphatase activity in the serum was 828 U/l (our reference range in adults: 57-194 U/l), 94% of which was of the intestinal type as measured by an immunoprecipitation method. The intestinal component of alkaline phosphatase was separated into two major and some minor components using electrophoresis and isoelectrofocusing. One of the major components had similar mobility to that of a standard intestinal enzyme purified from adult intestine. The components were heat-labile and neuraminidase-resistant. Serial lectin affinity chromatography, however, indicated that sugar chain compositions of the alkaline phosphatase were different from those of the standard tissue intestinal enzyme. These results and further enzymological studies suggest that the patient's serum alkaline phosphatase basically consisted of several intestine-like isoforms.

MRI of anterior mediastinal tumors

To compare the abilities of MRI (magnetic resonance imaging) and CT to provide information about anterior mediastinal tumors, we retrospectively evaluated the MR (n = 28) and CT images (n = 25) of patients with anterior mediastinal tumors. T1-weighted and T2-weighted images were obtained with spin echo sequences using cardiac gating. Six of 12 thymomas and seven of nine teratomas showed characteristic findings by MRI, while four of the 10 thymomas and five of the eight teratomas were correctly diagnosed by CT. The other tumors did not show a characteristic MR appearance. All nine malignant tumors were correctly diagnosed as malignant lesions on MR images, while one false positive case and one false negative case were recorded on CT images. We conclude that MRI and CT provide nearly the same information for the evaluation of anterior mediastinal tumors. However, in some cases, only MRI can provide information about malignancy or a specific diagnosis.