Reproducibility of magnetic resonance spectroscopy in patients undergoing dialysis and evaluation of the therapeutic response of tumors

RATIONALE AND OBJECTIVES

The reproducibility of repeated magnetic resonance (MR) spectroscopy was studied in patients undergoing dialysis and treatment of a variety of malignant tumors.

METHODS

Localized MR spectra were obtained using a 1.5-T system by image-selected in vivo spectroscopy. Total metabolite signal was integrated between phosphomonoester and beta-adenosine triphosphate resonance. We termed this measurement AREA.

RESULTS

Intrapatient variability was evaluated on repeated thigh muscle spectroscopy for 10 patients. Sequential spectra of 10 malignant tumors of the extremities were analyzed and compared with the histology of surgical specimens in seven patients. Intrapatient variability in AREA was calculated as 14.0%. The extent of necrosis and AREA ratio (definition: AREA post-therapy/AREA pretherapy) were as follows; 6.1% in > 90% necrosis, 43% in 50% to 90% necrosis, and 79% in < 50% necrosis.

CONCLUSIONS

Localized MR spectra are fairly reproducible and may relate to treatment efficacy.

Rat dilated cardiomyopathy after autoimmune giant cell myocarditis

One of the possible causes of dilated cardiomyopathy is considered to be a sequel to myocarditis. Two mechanisms have been proposed in the process of progression of myocarditis into dilated cardiomyopathy: one is a persistent viral infection, and the other is an autoimmune myocardial injury. To clarify the possible part played by the autoimmune mechanism in the process, using an animal model, we investigated whether autoimmune myocarditis, exclusively not related to viral infection, might develop into dilated cardiomyopathy. Experimental autoimmune myocarditis was elicited in Lewis rats by immunization with cardiac myosin fraction. Rats of the control group were immunized with ovalbumin. The clinical course was observed over 4 months. Six rats from the myosin-immunized group died during the acute phase and the healing phase, and all those rats had severe myocarditis. All rats that survived until the end of the study showed enlarged and discolored hearts. Aneurysmal changes were observed in the right ventricle during thoracotomy. The ratio of heart weight to body weight of the myosin-immunized group was significantly higher than that of the control group (3.36 +/- 0.49 versus 2.69 +/- 0.06 g/kg, respectively; P < .005). The lengths of the anterior interventricular fissure and the posterior interventricular fissure of the hearts of the myosin-immunized group were significantly longer than those of the control group. The external diameter of the left ventricle of the myosin-immunized group was also significantly larger than that of the control group. Diffuse myocardial muscle loss and replacement fibrosis were the prominent histological findings of the rats of the myosin-immunized group.(ABSTRACT TRUNCATED AT 250 WORDS)

Tissue residues of sulfadimethoxine following dietary administration to broiler-chickens

Broilers were divided into four groups and the first group served as the control. The second, third and fourth groups were given feed containing 25, 50 and 100 mg/kg of sulfadimethoxine (SDM), respectively, for 21 days, and thereafter each group received the SDM free feed. On certain days during the experiment period, three broilers in each group were sacrificed and tissues, including blood, heart, liver, spleen, gizzard, thigh muscle, breast muscle and fat, were collected and residual SDM were determined by HPLC. Two days after withdrawal, SDM in each tissue had decreased to below the detection limit of 0.01 microgram/g.

Primary chemotherapy for children with rhabdomyosarcoma of the 'special pelvic' sites: is preservation of the bladder possible?

Twenty-one children with rhabdomyosarcoma involving the "special pelvic" sites, defined as such occurring in the bladder, prostate, vagina and uterus, were treated with primary surgery between 1969 and 1977, and with primary chemotherapy beginning in 1978. Among 11 patients in the latter group who were placed in Clinical Group III (according to the classification of the US Intergroup Rhabdomyosarcoma Study (IRS), six showed partial response (PR) and underwent tumorectomy by radical surgery an average of 6 months after the start of treatment, and three showed complete response (CR) and were treated with further chemotherapy in the hope that cystectomy could be avoided. However, in the latter group, the tumor recurred (39 months, 35 months, and 27 months later), and all eventually underwent total cystectomy. Seven of the nine long-term survivors underwent total cystectomy and have premanent urinary-cutaneous stomas. Two had tumor-free bladders, but function was impaired in one because of the effect of irradiation. Normal function was preserved in only one patient in the series, whose tumor was located at the dome of the bladder. To preserve bladder function in children with rhabdomyosarcoma in these sites, more effective forms of chemotherapy will be required.

Morphological analysis of multinucleated giant cells occurred in experimental autoimmune myocarditis

Our previous study reported the rich existence of multinucleated giant cells in an autoimmune myocarditis experimentally induced in rats. The present study investigated the histochemical and ultrastructural characteristics of these giant cells. Histochemistry for an acid phosphatase clearly demonstrated multinucleated giant cells dispersed at the inflammatory foci. Ultrastructurally, the giant cells were shown to be single cells, but not clustered cells. Their ultrastructural characteristics were very similar to the basic features of macrophages, except that the giant cells were poor in lysosomes and phagosomes. It was noticeable that some macrophages possessed three or more nuclei, displaying an intermediate form between mononuclear macrophages and multinucleated giant cells. These findings suggest that the giant cell in the experimental autoimmune myocarditis is a single multinucleated cell, and possibly derived from macrophages by cell-to-cell fusion.

Altered production of nerve growth factor in aganglionic intestines

Nerve growth factor (NGF), a target-derived neurotrophic molecule, is required specifically by sympathetic and dorsal root ganglion cells for their survival and maturation during embryonic and early postnatal development. In the present study, the NGF expression was studied both at the protein and mRNA level in normal and aganglionic intestines of Piebald-strain mice and also in 10 human specimens using immunohistochemical and reverse transcriptase polymerase chain reaction (RT-PCR) techniques. In the aganglionic intestines of the mice, immunoreactive NGF was found on the giant nerve fibers in the submucosal layer, but not found in the mucosal layer. In the mRNA study, the signal for NGFmRNA was less intense in the aganglionic rectum of the congenitally megacolonic mice than in the rectum of the normal mice. In contrast, the distal dilated colon of the congenitally megacolonic mice had a more intense signal for NGFmRNA than did the colon of normal mice. The results obtained from human specimens were compatible with the findings in the Piebald mice; the distal colons harvested from the patients with Hirschsprung's disease (or its allied disease) had a uniformly more intense signal for NGFmRNA than did the normal colons. The results of this study may indicate that NGF production is altered in the aganglionic intestines and also in the "transitional zone" in Hirschsprung's disease. The altered production of NGF may be useful in increasing the accuracy of diagnosis of Hirschsprung's disease.

Electrophysiological studies on light damage in the mouse retina after sodium iodate injection

Acute experimental retinal degeneration was induced in 3-month-old mice with sodium iodate (NaIO3) injection to investigate the effect of bright light with electroretinography (ERG). Eight C 57 black male mice were anesthetized. The ERG was recorded before and 24 h after the injection of NaIO3. Next, only one eye of each mouse was exposed to a bright light of 3.0 x 10(4) lx white light for 30 min. Ten hours later, ERGs of both the light-exposed and the unexposed eye were recorded. The amplitudes and peak latencies of the a wave and b wave were measured. The ERG was recorded as both eyes were exposed to stimulating flashes that were given in an increasing order of 0.6 log unit steps from the dimmest flash to produce a detectable ERG. The ERG from the light-exposed eye showed a distinctly elevated threshold (approx 2.0 log), while the contralateral unexposed eye did not. The peak latencies of both waves were significantly prolonged by exposure to light. In conclusion, light exposure affected ERG thresholds in mice with experimentally induced acute retinal degeneration.

Identification of a functional receptor differing from the LDL receptor that catabolizes chylomicron remnant in Hep G2 cells

We investigated types of lipoprotein receptors on Hep G2 cells using a monoclonal antibody against the LDL receptor. IgG-C7 inhibited the binding and internalization of 125I-labeled low density lipoprotein (LDL) in Hep G2 cells with upregulated and downregulated LDL receptors by 90% of control values. Binding and internalization of 125I-labeled chylomicron remnant in Hep G2 cells with upregulated and downregulated LDL receptors was 50% and 85%, respectively, of control values after exposure to IgG-C7. Excess unlabeled chylomicron remnant inhibited binding and internalization of 125I-labeled chylomicron remnant in Hep G2 cells with downregulated LDL receptors completely. Pronase treatment abolished binding and internalization of 125I-labeled LDL and 125I-labeled chylomicron remnant in Hep G2 cells. When solubilized fractions of Hep G2 cells were immunoprecipitated with IgG-C7, the binding activity of 125I-labeled chylomicron remnant to reconstituted vesicles was unchanged. 45Ca blotting analysis showed the presence of 45Ca binding protein (approximately 600 kDa) in Hep G2 cells. The amount of 45Ca binding protein was not affected by cholesterol and was abolished by pronase treatment. These results suggest the existence of a functional receptor other than the LDL receptor that catabolizes chylomicron remnant in Hep G2 cells and that this receptor may correspond to LDL receptor-related protein.

FK506 therapy of experimental autoimmune myocarditis after onset of the disease

Preventive effects of FK506 on autoimmune myocarditis have been demonstrated, but the therapeutic efficacy of the agent in established myocarditis yet remains to be assessed. In this study, effects of FK506 on experimental autoimmune myocarditis were investigated by the use of the agent after the onset of the disease. Lewis rats were immunized with either cardiac myosin or bovine serum albumin (BSA) in complete Freund's adjuvant. The onset of the disease was ascertained by examining randomly chosen cardiac myosin-immunized rats. Animals were divided into four groups: the BSA-immunized saline-treated group (group A, n = 6); the BSA-immunized FK506-treated group (group B, n = 6); the myosin-immunized saline-treated group (group C, n = 6); and the myosin-immunized FK506-treated group (group D, n = 11). Saline or 1.0 mg/kg/day of FK506 were intramuscularly injected from day 16 to day 27. All the rats were put to death on day 28. Rats of group C became severely ill by the third week, while in contrast, rats of group D remained active, as did rats of groups A and B. The heart weight/body weight ratio was significantly lower in group D than in group C rats. Group mean values were 3.48 +/- 0.10 gm/kg for group A, 3.48 +/- 0.16 gm/kg for group B, 4.94 +/- 0.66 gm/kg for group C, and 3.88 +/- 0.43 gm/kg for group D. Rats of group C showed severe myocarditis with mononuclear cell infiltration, myocardial necrosis, and interstitial edema.(ABSTRACT TRUNCATED AT 250 WORDS)

[Biliary lithotripsy using super fine cholangioscopy with the deviced bended sheath]

Percutaneous transhepatic cholangioscopy (PTCS) is an useful technique to evaluate or treat biliary diseases, although PTCS is an invasive method for the patients. We used 5 F or 7 F of super fine cholangioscopy to treat two cases of choledocholithiasis after surgery without dilatation of drainage tract. We developed different types of bended sheath for supplement of lack of angle system in this cholangioscope. Furthermore, by using bended sheath, cholangioscopic view improved, because saline was injected at the same time via the sheath. We emphasize that super fine cholangioscope with bended sheath is a safe and useful modality for evaluation of biliary disease.

Sacroperineal anorectoplasty using intraoperative ultrasonography: a preliminary report

Intraoperative ultrasonography (US) was applied to sacroperineal anorectoplasty for the purpose of making a pull-through tunnel under visual guidance. Intraoperative US images the horizontal plane of the muscle complex and the tip of the forceps, which is placed at the entrance of the tunnel (ie, the space anterior to the puborectalis sling), ready to penetrate the muscle complex. A surgeon can thus penetrate the center of the muscle by confirming the relation between the muscle and forceps on the US screen. Postoperative computed tomography of four patients on whom this technique was applied demonstrated that the rectum was pulled through the exact center of the puborectalis and external sphincter muscles.

Electrical resonance of isolated hair cells does not account for acoustic tuning in the free-standing region of the alligator lizard's cochlea

The cochlea of the alligator lizard is divided into two morphologically and physiologically distinct regions. In the "tectorial region," hair bundles of hair cells are draped by a tectorial membrane, whereas in the "free-standing region," hair bundles are said to be free-standing because there are no overlying tectorial structures. The acoustic tuning of the free-standing region depends at least in part on mechanical resonances of the hair bundles. In the turtle cochlea, in contrast, acoustic tuning depends in large part upon the electrical properties of the hair cells. We have investigated the electrical properties of hair cells isolated from the free-standing region of the alligator lizard's cochlea. When injected with steps of depolarizing current, these "free-standing hair cells" exhibited electrical resonances that were comparable in frequency and quality to electrical resonances in cochlear hair cells from turtles, chicks, and alligators, and in saccular hair cells from frogs and fish. In the lizard's free-standing hair cells, however, the electrical resonance frequencies (< 300 Hz) were a decade below the cells' acoustic characteristic frequencies (between 1 and 4 kHz), showing that the electrical resonance is not likely to contribute to acoustic tuning. The electrical resonances were not apparent at rest. The cells' resting potentials were significantly more negative than the activation voltage (approximately -40 mV) of the Ca(2+)-dependent K+ current upon which the electrical resonance has been shown to depend in other hair cells. At potentials more negative than -50 mV, an inwardly rectifying K+ conductance dominated. Because we observed no electrical tuning above 300 Hz, our results indirectly support a mechanical origin for acoustic tuning in the free-standing region of the alligator lizard cochlea. These results further show that acoustic tuning cannot be inferred solely from the electrical resonances of isolated hair cells.

Partial cloning of cDNA for hamster liver cholesterol 7 alpha-hydroxylase

A partial cDNA clone encoding cholesterol 7 alpha-hydroxylase (pHA 7 alpha-3) was isolated from a hamster liver cDNA library using rat P-450 ch7 cDNA (p 7 alpha-11) as a probe. In comparison with the complete base sequence of p 7 alpha-11, pHA 7 alpha-3 lacked about 500 base pairs at the 5' end. Circadian rhythms of mRNA for hamster liver 3-hydroxy-3-methylglutaryl coenzyme A reductase and cholesterol 7 alpha-hydroxylase were investigated with cDNA clones encoding 3-hydroxy-3-methylglutaryl coenzyme A reductase (pRed-227) and pHA 7 alpha-3. Typical circadian rhythms of mRNA for both enzymes and a time lag between the two circadian rhythms were observed. The circadian rhythm of activity for each enzyme corresponded to that of each mRNA.

Cardiac contractile proteins and autoimmune myocarditis

Concerning cardiac contractile proteins, antigenicity and myocardiotogenicity were discussed. In normal states, these proteins are immunologically tolerant, and can not provoke any heart-specific disease. Why the proteins can provoke such lethal autoimmune myocarditis has not been completely elucidated. Shortly after cardiac infection or myocardial ischemia, these proteins may work as the antigen for the autoimmune myocarditis. First of all, the role of cardiac myosin has been strongly emphasized. But, the antigen determinants: epitope proteins remain unclear. Either cross-activity to the streptococcal M protein and/or the alpha-helical coiled-coil protein may be an important factor to determine antigenicity. In this autoimmune myocarditis, the roles of T-lymphocyte and cardiac dendritic cell are noticeable. Through further study on the relation between antigen epitope and the infectious agents in the heart; on cardio-cytotoxicity of the T-lymphocyte and on the precise contribution of cardiac dendritic cells, this autoimmune myocarditis will be more clarified.

Effect of dietary hydrogenated corn oil (trans-octadecenoate rich oil) on plasma and hepatic cholesterol metabolism in the hamster

The effect of dietary hydrogenated corn oil (trans-octadecenoate-rich oil) on plasma cholesterol and triglyceride concentrations was compared with dietary palmitic acid in hamsters given a cholesterol-rich diet. The addition of dietary palmitic acid and hydrogenated corn oil accelerated the increase in plasma VLDL- and LDL-cholesterol levels and plasma triglyceride level induced by dietary cholesterol loading. Dietary cholesterol, palmitic acid and hydrogenated corn oil showed no effect on plasma HDL-cholesterol concentration. A decrease in hepatic LDL receptor activity was seen in animals fed a diet supplemented with cholesterol in combination with palmitic acid or hydrogenated corn oil in comparison with animals fed a diet supplemented with cholesterol alone. Hydrogenated corn oil (trans-octadecenoate-rich oil) appears to potentiate the effect of dietary cholesterol in elevating the plasma VLDL- and LDL-cholesterol levels through the suppression of hepatic LDL receptor activity. trans-Octadecenoate in dietary hydrogenated corn oil may be as atherogenic as dietary palmitic acid due to a suppression of hepatic LDL receptors in the presence of dietary cholesterol loading.

Determination of pyrimethamine and sulphadimethoxine residues in eggs by high performance liquid chromatography

1. Laying hens were given food containing per kg diet: 1 mg pyrimethamine, 10 mg sulphadimethoxine (SDM) or 1 mg pyrimethamine with 10 mg SDM, for 14 days. Residues in the eggs were determined by high performance liquid chromatography. 2. Pyrimethamine was mainly found in yolk. Its concentration was slightly higher when it was given with SDM. 3. The concentrations of SDM in eggs were not different when it was given alone or in combination with pyrimethamine. 4. After withdrawal, pyrimethamine residues decreased below the detection limit (0.02 mg/kg) in the yolk after 11 to 12 d and in the albumen after 2 to 3 d. SDM in yolk fell below the detection limit (0.01 mg/kg) on day 7, whereas in albumen it was not detectable after 2 to 3 d.

What is the clinical disadvantage of discarding old radiographs? Survey of patients not re-examined for a long time

The clinical disadvantage of discarding old radiographs was evaluated in patients who had not been re-examined for more than 8 years after their last radiological examination, 38,772 in total. During the 1 year survey, 158 (0.41%) of them underwent re-examination after a long interval. Retrospective evaluation revealed that in only 12 patients (0.032%) were the old films useful. This survey suggested that the clinical risk of not referring to films more than 8 years old would be less than 0.049%. We consider this acceptable, and have formulated new guidelines of storage of films.

[Clinical application of 31P MRS to malignant liver tumors--with an emphasis on evaluation of response to therapy]

Malignant liver tumors in 19 cases (13 hepatomas and 6 metastatic tumors) were studied by 31P magnetic resonance (MR) spectroscopy. Five healthy volunteers were also studied. Volume localization was performed using the ISIS sequence. Compared with normal liver, the MR spectra of malignant tumors showed an elevated phosphomonoester (PME) peak relative to beta ATP (p less than 0.005), and tumors were slightly alkaline (pH 7.32 +/- 0.08) before therapy. Nine cases of hepatomas responding to chemoembolization showed extremely reduced signal intensity of spectra. Tumor pH was compared before and after therapy in four cases that showed good response to therapy, and was elevated in all of them. Three metastatic tumors with good response showed reductions in PME and ATP after therapy. MR spectroscopy with adequate localization technique is useful in demonstrating the response of malignant tumors to therapy.

[Signal contamination problem in three-dimensional localization technique of MR spectroscopy--experiment and an analysis of patient data]

Signal contamination from the surrounding volume was studied using the ISIS sequence, a three-dimensional localization technique. In phantom experiments, contamination decreased with the increase of Tr, regardless of where the contamination originated from. In 52 localized liver spectra with a Tr of 2 sec, PCr contamination was estimated at 3 to 4%, and contamination of ATP signals from the surrounding liver tissue at less than 1%, because of the relatively short T1 of ATP in the liver. In the spectra of brain neoplasms obtained using the simultaneous double-volume selection technique, the PCr ratio in the tumor relative to the control area was high in low grade astrocytoma (0.80, n =8) and low in others (0.45, n = 11). Considering contamination and spectral noise, a PCr ratio of less than 0.4 does not strongly suggest the existence of PCr in tumors. Among 25 cases whose therapeutic processes were monitored by MRS, signal disappearance was observed in two cases in the localized spectra after therapy. In both of them, tumor necrosis was proved pathologically and correlated well with spectroscopic findings. It was found that the ISIS technique suppressed signal contamination to the level of several percents, providing spectra of acceptable quality through localization.

High performance liquid chromatographic determination of trimethoprim residues in egg yolk and albumen in a feeding experiment

In a feeding experiment, the residues of trimethoprim (TMP) in egg yolk and albumen were determined by high performance liquid chromatography (HPLC). Laying hens were divided into four groups. The first group was designated as control and fed with TMP free diet during the experimental period. The second, third and fourth groups were administered with the feeds containing 4 p.p.m., 16 p.p.m. and 56 p.p.m. TMP, respectively, for 19 days and, thereafter, fed with TMP free diet. TMP was mainly found in yolk in all the three administered levels. In the medication period, the average concentration of TMP in the yolk of the second, third and fourth groups was 0.05, 0.25, and 0.90 p.p.m., respectively. After withdrawal of medication, the residues of TMP in yolk in the second, third and fourth groups decreased below the detection limit at 0.02 p.p.m. on days 4, 9, and 11, respectively.