[Esophageal perforation after replacement of descending thoracic aorta for rupture mycotic aneurysm]

Primary mycotic aneurysm of the thoracic aorta has rarely been reported. The patient was a 61-year-old male who had a ruptured mycotic aneurysm of the descending thoracic aorta without any evidence of infectious disorders in his history. The patient developed esophageal perforation after graft replacement of the descending thoracic aorta. After continuous irrigation of the left pleural cavity and the mediastinum for one month, the thoracic esophagus was resected and reconstructed. However, the patient died of DIC following uncontrolled sepsis on the 98th postoperative day. Pathogenesis of the esophageal perforation and operative procedures that might have been effective in saving the patient were discussed.

[Two cases of aorto-coronary bypass grafting for two different types of single coronary artery]

Single coronary artery is a rare congenital anomaly and its prognosis is good. This entity can be diagnosed only by coronary angiography in lift. Atherosclerotic obstruction of a single coronary artery causes a high incidence of sudden death, so this anomaly does not take a good course. We present two cases of CABG which have two different types of single coronary artery with some significant stenoses of the coronary arteries.

[A case report of light and heavy chain deposition disease (IgG2 lambda)]

A 73-year-old male was admitted to the renal division of our hospital because of hypertension, proteinuria and bilateral pretibial edema. Eight years previously, he was diagnosed as being afflicted with interstitial pneumonia on the basis of a chest X-ray examination. Laboratory tests conducted during the current admission showed normocytic normochromic anemia, renal dysfunction and mild proteinuria. Total IgG was normal, but a high proportion of IgG2 was observed. M-protein in the serum was positive for both IgG lambda and Bence Jones protein (lambda type). A bone marrow biopsy showed the proportion of plasma cells to be 10.6%, but atypical cells were not found. We diagnosed the patient's condition as plasma cell dyscrasia. Light microscopy examination of a renal biopsy specimen showed moderate mesangial proliferation with a deposition of PAS-positive and Congo red negative materials in the mesangial area: nodular gomerulonephritis was seen in some glomeruli. Immunofluorescence revealed IgG and lambda light chains, strong linear staining along the glomerular basement membrane and tubular basement membrane and positivity in the mesangial area. Results of staining for IgA, IgM, fibrinogen and C3 were weakly positive in the mesangium area, while those for C4, Clq and free kappa were negative. Positive staining of IgG2 was seen by immunoperoxidase study, but the tissue was negative for IgG1, IgG3, IgG4. Electron microscopy demonstrated a dense granular deposition in the mesangial, subendothelial and peritubular area and a microfibrillar structure in the mesangial area. The diameter of the microfibrillar structure was 14 nm on the average.(ABSTRACT TRUNCATED AT 250 WORDS)

Specific cleavage of secretory leukoprotease inhibitor by neutrophil elastase and saliva

In an attempt to explore the process of naturally occurring secretory leukoprotease inhibitor (SLPI) fragmentation, the cleavage profile of SLPI, which had been prepared by recombinant techniques, was investigated biochemically. Restricted fragments of SLPI were detected using SDS-PAGE after treatment with human neutrophil elastase (NE) or normal saliva and sequenced at their cleavage sites. Among these restricted fragments, two species of nearly half-length SLPIs that contained the C-terminal domain, (Arg58-Ala107)SLPI and (Arg59-Ala107)SLPI, were detected. They were both as active at inhibiting NE as the parent SLPI. These results suggest that functional SLPI derivatives may be generated physiologically in the respiratory tract under inflammatory and healthy conditions.

Computed tomography on renal masses in dogs and cats

Computed tomography (CT) was performed on renal tumors (Wilms' tumor and renal cell carcinoma) and renal cysts in dogs and cats. CT images in renal tumors were well correlated with macroscopic findings, and contrast CT images were quite useful in differentiating tumoral regions from non-tumoral ones. On renal cysts, intravenous pyelography and ultrasonography were as effective as CT images in morphological diagnosis, but CT was considered to be superior for evaluating three-dimensional (3-D) relationships in complicated lesions.

Effects of a benzothiazepine calcium blocker on electrolyte alteration in human ischemic and reperfused myocardium

Intracellular electrolyte alterations of the myocardial cells from the patients pretreated and non-treated with diltiazem in coronary surgery were measured by means of X-ray microanalysis. Myocardial biopsy specimens were obtained at the right atrial wall at non-ischemia, ischemia and reperfusion periods. The ion concentrations at non-ischemia which is the condition of pre-open heart surgery in patients were: Ca 0.8 +/- 0.05, K 108 +/- 2.3, Na 10 +/- 1.9, Cl 30 +/- 1 (mean +/- S.E., mmol/kg wet weight, n = 100-130), and there were no significant differences for Ca, K, Na and Cl with diltiazem administration. The intracellular Ca increased without diltiazem in reperfusion after open heart surgery. However, there was no Ca increase in either the ischemia or reperfusion states with diltiazem. The K content was significantly lower, and the Na and Cl contents were higher than those of non-ischemia in both ischemia and reperfusion without diltiazem. The K loss, and Na and Cl increases in the reperfusion period were recovered to the levels in the non-ischemia state with diltiazem administration. This study showed that the use of calcium-free cardioplegic solution caused intracellular calcium accumulation in a hypothermic global ischemic and reperfused conditions during coronary surgery, whereas, diltiazem could suppress the calcium accumulation. The alterations of potassium, sodium and chlorine were also favourable in patients with diltiazem. The possible mechanism of the effects of diltiazem on the element alterations of myocardium are discussed.

Progressively increased serum 1,25-dihydroxyvitamin D2 concentration in a hypoparathyroid patient with protracted hypercalcemia due to vitamin D2 intoxication

A 76-year-old female patient who had been taking vitamin D2 100,000 U/day for more than 14 years due to hypoparathyroidism following total throidectomy was admitted because of protracted hypercalcemia. On admission, the levels of serum vitamin D2 (99.8 ng/ml) and 25-OHD2 (356 ng/ml) were very high, and 1,25-(OH)2D2 was low (4.0-18.7 pg/ml). Serum D3' 25-OHD3 and 1,25-(OH)2D3 were below the normal range. Despite intensive hydration with saline, intravenous hyperalimentation with phosphate- and calcium-free nutrients, and administration of glucocorticoid and calcitonin, the hypercalcemia persisted, accompanied by hypoproteinemia, edema, pleural effusion and congestive heart failure. The serum D2 and 25-OHD2 concentrations remained high and were accompanied by a gradual increase in 1,25-(OH)2D2 (121 pg/ml), which further increased after the administration of bisphosphonate (pamidronate) to 183 pg/ml. Seventeen months later, serum calcium and 1,25-(OH)2D2 were normalized but serum D2 and 25-OHD2 remained high. The serum 24,25-(OH)2D2/25-OHD2 ratio was relatively constant throughout her clinical course, whereas the low serum 1,25-(OH)2D2/25-OHD2 ratio at admission gradually increased during admission, suggesting that the increase in serum 1,25-(OH)2D2 is due to increased production rather than decreased degradation. The administration of pamidronate further increased serum 1,25-(OH)2D2. These features of the clinical course demonstrate that the 1,25-dihydroxyvitamin D concentration in hypercalcemic patients with protracted vitamin D intoxication may be decreased, normal or increased. Possible factors responsible for a protracted increase in serum 1,25-(OH)2D2 are body weight loss, hypoproteinemia, and phosphate depletion. In addition, some bisphosphonates would certainly promote PTH-independent production of 1,25-(OH)2D2.

[Gluteal abscess caused by Staphylococcus aureus in a patient with systemic lupus erythematosus]

We describe here a 44-year-old female patient with systemic lupus erythematosus (SLE), who developed gluteal abscess resulting in symptoms suggestive of aseptic necrosis of the right femoral head. The patient was diagnosed as active SLE with organic brain syndrome in December 1992, and has been treated with high doses of methylprednisolone (initial dose: 100 mg daily). As she recovered from the manifestations, the dose of methylprednisolone has been gradually decreased. In June 1993, she began to complain of right leg pain on walk with positive Patrick sign in the right hip. A massive gluteal abscess was identified by X-ray and CT scan, and drained. Cultures of the purulent fluid yielded Staphylococcus aureus. Of note, Staphylococcus aureus had been detected from repeated cultures of pharyngeal swabs, suggesting that the organism invading from the pharynx was carried in the blood to a small hematoma in the right gluteal muscle to form an abscess. The importance of an awareness of the possibility of the infection of Staphylococcus aureus in SLE patients is discussed.

Hemolytic uremic syndrome without hemolytic anemia: a case report

Hemolytic uremic syndrome (HUS) is characterized by microangiopathic hemolytic anemia, thrombocytopenia and acute renal failure. Most cases of HUS are caused by E. coli O157:H7 verotoxin. In the case reported here, diarrhea continued for twenty days after an E. coli 0157:H7 infection and was followed by acute renal failure and thrombocytopenia. Examination of percutaneous renal biopsy tissue showed typical HUS findings, e.g., mesangiolysis in glomeruli and thickening of capillary walls with prominent double outlines, but there was no indication of hemolytic anemia. LDH and haptoglobin, indications of hemolytic anemia, were in the normal range throughout the patient's clinical course. The patient's red blood cells had P1 antigen, which reportedly provides protection by adsorption of toxin into the red blood cells thereby preventing or limiting toxic damage to other organs. Therefore, we assumed that because of the expression of P1 antigen in this patient, the kidneys were not severely damaged and microangiopathic hemolytic anemia was thereby avoided.

[Reoperation for mitral valve disease]

From 1978 to March 1994, 95 patients underwent repeated open heart surgery for mitral valve diseases. There were 48 men and 47 women. The mean age was 50 and the mean interval between initial and second operation was 8 years. The initial operations were OMC in 39, MAP in 13, OMC+MAP in 11, MVR in 30 and AVR in 2 patients. The hospital death occurred in 31 cases (32.6%). In recent cases, however the hospital death were reduced to 4 (14.8%). This was attributed to the change in myocardial protection from previous intermittent antegrade crystalloid to recent continuous combined antegrade and retrograde cardioplegia.

[Multicenter prospective study of retinopathy of prematurity--IV. Comparison with the data from University of Miami]

We investigated the records of 360 cases of retinopathy of prematurity (ROP) in 12 institutions in Japan (we treated the severe progressive "plus" disease by coagulation therapy), and compared them with data from University of Miami (Ophthalmology 94: 620-629, 1987), as representative of the natural course of ROP without coagulation therapy in those days. The timing of the first examination and the first positive diagnosis were later at University of Miami than in Japan. The time of maximal severity of the disease and occurrence of regression were also later the University of Miami than in Japan. In Japan, the first examination was performed at 29 weeks of postconceptional age or at 3 weeks after birth. At the University of Miami, the first examination was performed at 32 weeks of postconceptional age. If the severe progressive "plus" disease is to be properly treated by photo-coagulation or cryotherapy, it is essential to commence fundus examination earlier.

[Multicenter prospective study of retinopathy of prematurity--II. Optimum timing of the first examination]

We reviewed the records of 360 cases of retinopathy of prematurity (ROP) in 12 institutions in Japan, and investigated the optimum timing of the first examination. On the basis of the onset of ROP and the timing of the first treatment, the first ophthalmological examination should be performed 3 weeks after birth or 29 weeks of postconceptional age at the latest. Regarding the visibility of the fundus, there was little hazy media after 29 weeks of postconceptional age. Under the basic policy that the severe progressive "plus" disease should be properly treated, we concluded that the first ophthalmological examination should be performed 3 weeks after birth at the latest. When the gestational age at birth is less than 26 weeks, funduscopy at the post conceptional age of 29 weeks is advisable.

[Multicenter prospective study of retinopathy of prematurity--III. Timing of the coagulation therapy and the course of retinopathy of prematurity after coagulation]

We reviewed the records of 360 cases of retinopathy of prematurity (ROP) in 12 institutions in Japan, and investigated the timing of the coagulation therapy and the course of ROP after coagulation. The first coagulation therapy was performed at 9.6 weeks after birth and 35.9 weeks of postconceptional age on the average. The severity index in individual infants also showed that the disease became worse during the period from 32 to 36 weeks of postconceptional age. However, the fundus was clearly visible and there was no primary hazy media during this period. On the basis of the results of the timing of the first treatment, the visibility of the fundus, and the severity index in individual infants, we concluded that an ophthalmological examination with special care should be performed during the period from 32 to 36 weeks of postconceptional age.

Effects of medetomidine-midazolam on plasma glucose and insulin concentrations in laboratory pigs

Effects of medetomidine (40 micrograms/kg)-midazolam (0.2 mg/kg) on plasma glucose and insulin concentrations were evaluated in laboratory pigs. Intramuscular injection of medetomidine-midazolam induced a gradual hyperglycemic response associated with hypoinsulinemia which was much smaller than that by 80 micrograms/kg of medetomidine alone and was almost within a physiological fluctuation. These mild responses induced by medetomidine-midazolam were antagonized by use of an alpha 2-adrenoreceptor antagonist atipamezole (160 micrograms/kg), therefore those changes were thought to be mainly attributed to the effect of medetomidine on alpha 2-adrenoreceptors. A combination of medetomidine at a low dose and midazolam reduces undesirable effects, while providing more profound sedation than medetomidine alone in laboratory pigs.

Evaluation of regional cerebral blood flow changes on perifocal brain tissue SPECT before and after removal of arteriovenous malformations

In fifteen cases of arteriovenous malformation (AVM), serial examinations of regional cerebral blood flow (rCBF) using single photon emission computed tomography (SPECT) and N-isopropyl-(123I)p-iodoamphetamine were performed. On SPECT images, the nidus was visualized as a focal rCBF defect in all cases preoperatively and seven of these cases had abnormal decreased perfusion areas in the tissues adjacent to the nidus. In five cases, the postoperative SPECT images on the day after surgery revealed an abnormal increased perfusion area adjacent to the nidus and in one case the increased perfusion was accompanied by a massive intracerebral haemorrhage detected by brain computed tomography (CT). In seven cases, postoperative SPECT images showed widespread abnormal decreased perfusion areas in the surrounding tissues and brain CT revealed either intracerebral haemorrhage or significant cerebral oedema. In the other three cases, no remarkable rCBF changes were found in comparison with the pre-operative study. There was a tendency for the preoperative abnormal decreased perfusion area adjacent to the nidus to correlate with the postoperative hyperperfusion and for the postoperative abnormal decreased perfusion area to reflect brain damage.

[In vivo characteristics of IBZM in rat brains: an agent for quantitative SPECT imaging of dopamine D2 receptors. Preparation of 125I-IBZM and its biodistribution and kinetic properties]

123I-(S)-(-)-3-iodo-2-hydroxy-6-methoxy-N-[(1-ethyl-2-pyrrolidinyl) methyl]-benzamide (IBZM) is a CNS dopamine D2 receptor imaging agent for SPECT and has already been used clinically in the United States, Canada and Europe. However, methods of quantitative SPECT measurement of the D2 receptor density have not been well established. We performed in vivo biodistribution studies of 125I-IBZM in rat brains as the first step toward establishment of a basis for quantitative SPECT imaging of D2 receptors in humans. 125I-IBZM was prepared by the chloramine-T method. Radiochemical yields were 80 to 90% and radiochemical purity was 94.7% on day 81 after labeling. At 10, 30, 60 and 120 min after injection of the radiopharmaceutical, the percent uptakes (% dose/g) in the rat striatum were 2.9, 1.9, 1.7 and 1.0, respectively. These kinetic data were considered suitable for SPECT imagings. Pretreatment with haloperidol (1 mg/kg) blocked specific striatal uptake and there was a significant reduction in the uptake to 40.9% of the unblocked uptake at 60 min after injection (p = 0.006). The regional IBZM uptake ratio of striatum-to-cerebellum increased steadily from 1.7 at 10 min to 5.7 at 120 min. This suggests that SPECT imaging must be done during fixed time after tracer injection for the semiquantitative ratio to be meaningful.

Novel growth promoting activity with a wide target cell spectrum is present in extracts of various cell types

Cell extracts from a variety of cell lines, myeloid, T, B, mastocytoma, fibroblast, melanoma and breast carcinoma of human, mouse and guinea pig promoted the growth of a wide variety of cell types, namely human myeloid cells HL-60, human B cells Daudi, human melanoma cells A375-C6, mouse transformed-fibroblast cells L929, human myelomonocytic cells THP-1. Among them, the activities in extracts from U937, A375-C6 and Daudi were characterized because these extracts exhibited much more potent activity. These growth promoting activities were acid-labile, sensitive to 2-mercaptoethanol and to heat treatment at 50C or 70C for 5 min. The activities were also sensitive to proteases indicating the proteinous nature of these active entities. The molecular weight of activities from A375 and Daudi cells were estimated to be 100,000-150,000 daltons by gel filtration high performance liquid chromatography, while that from U937 cells was 60,000-70,000 daltons. The isoelectric point of these activities were 5.5-6.5.

Plasma concentrations of substances suspected as uremic toxins in experimentally induced and spontaneous uremic dogs

Plasma concentrations of four substances, a pyridine derivative (S7a), uric acid (UA), hippuric acid (HA) and kynurenic acid (KA), suspected as uremic toxins in dogs were determined in dogs with experimentally induced uremia by the ligations of renal arteries, spontaneous uremic dog patients and normal dogs. In experimentally induced uremic dogs, plasma concentrations of S7a, HA and KA showed continuous increase after the ligation of renal arteries together with a significant correlation to plasma creatinine concentration (Cre). Plasma UA concentration increased rapidly, but it showed a varying fluctuation without showing any correlation to Cre. Plasma concentrations of S7a, UA, HA and KA in spontaneous uremic dogs were almost within the ranges of those of experimentally induced uremic dogs.

Relationships between radiography of cervical vertebrae and histopathology of the cervical cord in wobbling 19 foals

Nineteen wobbling foals (17 males and 2 females) showing lameness of hindlimbs at 6 to 21 months of age were investigated radiographically and histopathologically. Minimum sagittal diameter (MSD), minimum flexion diameter (MFD) and minimum dural sagittal diameter (MDD) were measured on plain radiograms or myelograms taken at neutral and flexed positions as indicators of narrowed vertebral canal. After necropsy, the cervical spines and the spinal cord were examined macroscopically and respectively the relationships between radiographic findings and the corresponding morphological lesions were evaluated. Radiographically, lower values than each minimum reference limits were recorded in 14 foals in MSD, 5 foals in MFD and 6 foals in MDD, respectively. According to the histopathologic examination, the disappearance of axons and myelin sheaths, vacuolated spongy degeneration and appearance of macrophages were recognized symmetrically in the white matter of the cervical cord. These lesions were centrally located at the spinal cord radiographically demonstrated as compressed sites in 12 out of 17 foals examined. Macroscopically, asymmetrical overgrowth of one side of the process, encroachment of articular processes into the intervertebral foramina and proliferation of bone around articular facets were observed in the articular processes of bone specimens in the caudal neck of 6 foals. In conclusion, the equine incoordination might mainly be caused by the cervical stenotic myelopathy resulting from cervical vertebral malformation, and therefore the cervical vertebral radiography, especially myelography, is quite very important and effective for the diagnosis of wobbling foals.

Cardiopulmonary effects of medetomidine-midazolam and medetomidine-midazolam- atipamezole in laboratory pigs

The cardiopulmonary effects of medetomidine (40 micrograms/kg)-midazolam (0.2 mg/kg) and medetomidine (40 micrograms/kg)-midazolam (0.2 mg/kg)-atipamezole (160 micrograms/kg) were evaluated in laboratory pigs. The intramuscular administration of medetomidine-midazolam caused a pressor response, characterized by a rapid increase in arterial and pulmonary arterial pressure mediated mainly through systemic and pulmonary vasoconstriction. These pressures decreased after reaching a peak 5 to 10 min after the administration of sedatives, but maintained higher values than the base-line. However, all these changes caused by medetomidine-midazolam were within the physiological fluctuation. In addition, this combination did not induce bradycardia, subsequent hypotension or a significant decrease in cardiac output, which were generally observed with alpha 2-adrenoceptor agonists, and caused fewer changes in the respiratory system. The administration of atipamezole resulted in a marked transient decrease in vascular resistance, and caused a decrease in blood pressure and increases in cardiac output and heart rate. However, these changes were relatively small and sustained for a short time. Thus the combination of medetomidine-midazolam and atipamezole have minimal cardiopulmonary effects and might be used safely in laboratory pigs.

The binding properties, with blood proteins, and tissue distribution of 22-oxa-1 alpha,25-dihydroxyvitamin D3, a noncalcemic analogue of 1 alpha, 25-dihydroxyvitamin D3, in rats

The binding properties, with blood proteins, and tissue distribution of 22-oxa-1 alpha,25-dihydroxyvitamin (22-oxacalcitriol; OCT), a noncalcemic analogue of 1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3], in rats were investigated. The binding affinity of OCT to plasma vitamin D binding protein (DBP) is extremely low and OCT mainly circulates in the blood as an intact form nonspecifically bound to lipoproteins especially to chylomicrons and low density lipoprotein (LDL). OCT intravenously injected into normal rats rats rapidly disappeared from the blood, and rapidly appeared in the bile as glucuronides of intact OCT and 1 alpha, 3 beta,20(S)-trihydroxy-9,10-secopregna-5,7,10(19)-triene (23,24,25,26, 27-pentanorOCT; pentanorOCT) as an OCT metabolite. When OCT or 1,25(OH)2D3 was injected into normal rats, significant amounts of OCT and 1,25(OH)2D3 were quickly detected in the thyroid and parathyroid glands, thymus, adrenals, liver, plasma, small intestine, kidneys, and calvaria. The detected amounts of OCT in the parathyroid glands, thymus, adrenals, liver, small intestine, and kidneys were significantly higher than the respective values for 1,25(OH)2D3 2 and/or 10 min after injection, while those of OCT in the plasma and calvaria were significantly lower than those of 1,25(OH)2D3. The in vivo rapid turn-over, nonspecific transportation, and incorporation of detectable amounts into the tissues are typical characteristics of OCT which may account for its specific activities.

Bovine internal thoracic artery graft for myocardial revascularization: late results

From May 1988 to March 1990, the bovine internal thoracic artery (ITA) graft, 3 mm in diameter, was used for coronary artery bypass grafting in 29 patients with the approval of the Japanese Ministry of Health. Excluding three postoperative deaths and 6 patients who rejected postoperative angiography, 20 patients (13 men and 7 women; mean age, 62 years; range, 37 to 80 years) were followed up angiographically for up to 4 years. Sites of bovine ITA anastomosis were as follows: anterior descending, 4; circumflex, 5; and right coronary artery, 11. The mean bovine ITA graft blood flow measured by electromagnetic flowmeter was 75.2 mL/min (range, 40 to 150 mL/min). During the mean follow-up of 45 months (range, 30 to 52 months), 12 patients underwent postoperative angiography once, 6 patients twice, and 2 patients three times. It revealed 14 of 16 (88%) bovine ITA grafts were patent within 2 postoperative months. Three of 6 (50%) were patent at 3 to 12 months, of which 2 patent grafts required balloon angioplasty for distal anastomotic stenosis. In 7 patients restudied later than 1 year (20, 24, 25, 44, 48, 50, and 52 months), one of seven grafts (14%) was patent. There was stenosis (> or = 50%) at four distal and one proximal bovine ITA anastomotic sites, but no focal stenosis was found in the trunk at any period. There was one late death due to renal failure, one myocardial infarction, and one mild angina due to bovine ITA graft failure.(ABSTRACT TRUNCATED AT 250 WORDS)

[Surgical treatment of infective endocarditis]

Since 1976, 37 patients have undergone valve replacement for infective endocarditis at our institute. Twenty patients required surgery during the active stage and 17 in the inactive stage. The former group consisted of 17 native and three prosthetic valve endocarditis, and all patients in the latter group had native valve endocarditis. Eighteen patients had AVRs, 15 had MVRs and four had DVRs. Congestive heart failure was the indication for surgery in 80% of the active and 100% of the inactive group. There were nine early deaths (45%) and one late death in the active group, and one early (6%) and one late death in the inactive group. Operative mortality in the active group, however, has recently been reduced to 30% for the 10 patients operated upon in the past two years. Two patients with active endocarditis were complicated by rupture of cerebral mycotic aneurysms postoperatively and resulted in one early and one late death, respectively. It is suggested that timely surgical intervention according to the hemodynamic state of the patients is essential in reducing early mortality in infective endocarditis. Attention should be paid to cerebral mycotic aneurysm as one of the problems affecting on postoperative mortality and morbidity.

New monoclonal antibodies directed against mouse follicular dendritic cells

The follicular dendritic cells (FDC) in B-lymphoid follicles are unique reticular cells that retain immune complexes on their surfaces. We developed new monoclonal antibodies (MAb), SKY01, 28, 41, and 49, against mouse FDC without useful cell markers. Immunohistochemical study of spleen and lymph node tissues from Balb/c, C3H, and C57BL/6 mice revealed that SKY01 and 49 were highly specific for FDC, whereas SKY28 and 41 reacted with other stromal components as well as FDC. On immunoelectron microscopy (IEM), reaction products for all MAb were localized on the surfaces of FDC. In ontogenetic study of Balb/c spleen, FDC precursors were not immunodetected with any of the MAb at 1 week after birth. The FDC that first appeared as immune complex-retaining cells at 2 weeks were a subpopulation of SKY01-, 49-, 28+, and 41+ reticular cells. At 3 weeks, FDC were positive for all MAb, like adult spleen. These results indicate that our MAb recognize differentiation antigens of FDC. Comparative immunohistochemical studies of spleen from athymic nude and severe combined immunodeficiency mice suggested that B-cells may be required for the differentiation of FDC. Consequently, these MAb are considered useful tools for research on FDC.

Juvenile variant of Schimke immunoosseous dysplasia

We report on a 16-year-old girl with spondyloepiphyseal dysplasia, nephrotic syndrome, lymphopenia, and signs of defective cellular immunity. The manifestations are very similar to those reported by Spranger et al. [1991: J. Pediatr 119: 64-72] as Schimke immunoosseous dysplasia, except for age of onset. In Schimke immunoosseous dysplasia, growth retardations as an initial symptom is noted in early childhood and about 1 year after onset of progressive proteinuria. In our case the skeletal abnormality was noted at age 10 years as dislocation of the hip joints and the diagnosis of nephrotic syndrome was made at age 16 years. The findings strongly suggest that our patient has a juvenile variant of Schimke immunoosseous dysplasia.