Cholesterol lowering in low density lipoprotein receptor knockout mice overexpressing apolipoprotein E.

Apo E is a key molecule in the lipoprotein metabolism; thus, genetic manipulation of apo E may prove useful in the treatment of hypercholesterolemia. To test the feasibility of this idea, we have generated low density lipoprotein receptor (LDLR) knockout mice that overexpress the rat apo E transgene (ETg+/+:LDLRKO), and compared their plasma lipoprotein profiles with those of nonexpressing LDLR knockout mice (ETg-/-:LDLRKO). On a normal chow diet, the mean plasma cholesterol level of ETg+/+:LDLRKO mice was significantly lower than that of ETg-/-:LDLRKO mice (189 versus 240 mg/dl, P < 0. 01). The LDL fraction was selectively reduced in the ETg+/+:LDLRKO mice. Despite the challenge with an atherogenic diet, cholesterol lowering was persistently observed and fatty streak lesions in the aortic sinus were significantly suppressed in the mice overexpressing apo E. These results imply that stimulation of hepatic production of apo E may be used as a promising adjunctive therapy for homozygous familial hypercholesterolemia.

Bcl-2 protein inhibits oxysterol-induced apoptosis through suppressing CPP32-mediated pathway.

Oxysterols are presumed to mediate cytotoxicity of oxidized LDL in atherosclerotic lesions. To elucidate its molecular mechanism, we established murine macrophage-like P388-D1 cells which over-express Bcl-2 protein by retrovirus-mediated gene transfer. Oxysterols (7-ketocholesterol, 25-hydroxycholesterol) induced nuclear condensation and oligonucleosomal DNA fragmentation, which were partially inhibited by Bcl-2 over-expression. Though CPP32 inhibitor suppressed the cell death in control cells, it showed no additive protection in the cells over-expressing Bcl-2. These findings indicate that oxysterols induce apoptosis via Bcl-2-inhibitable and -uninhibitable pathways, and the former depends on CPP32 activation.

Synergistic effects of transforming growth factor-beta on the expression of c-fms, macrophage colony-stimulating factor receptor gene, in vascular smooth muscle cells.

Vascular smooth muscle cells (SMC) transform to foam cells in the process of atherosclerosis. We have reported that SMC derived from the intima of atherosclerotic lesions express c-fms, macrophage colony-stimulating factor receptor gene, which is not normally expressed in medial SMC. In the present study, we demonstrated that transforming growth factor-beta (TGF-beta) synergistically induced expression of c-fms in the presence of platelet-derived growth factor-BB in human medial SMC, a level comparable to that observed in the intima. The induction of c-fms was not inhibited by protein kinase C (PKC) inhibitor, suggesting that TGF-beta induces c-fms via a PKC-independent pathway. These results suggest that TGF-beta plays an important role in the phenotypic change of smooth muscle cells to macrophage-like cells in the process of atherosclerosis.

Apoptotic cell death in atherosclerotic plaques of hyperlipidemic knockout mice.

In an attempt to understand the roles of apoptosis in the development of atherosclerosis, we classified lesions developed in the aortas of apo E- and LDL receptor-deficient mice, murine models of atherosclerosis, and determined frequency, spatial distribution and cell types of apoptotic cells in each lesion. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and nuclear staining with propidium iodide were used to demonstrate apoptotic cells. Mean frequencies of TUNEL-positive cells were as follows: 0%, in Type I, 0.3% in Type II, 0.05% in Type III, 0.06% in Type IV and 0.06% in Type V lesions. Most of the TUNEL-positive cells were filled with fat and distributed in close proximity to lipid pools. The TUNEL-positive cells in the intimal side of the lipid cores were macrophages, while some of those in the adventitial side were smooth muscle cells. In conclusion, apoptosis is involved in the active turn-over of foam cells of both macrophage- and smooth muscle cell-lineage especially in the early atherosclerotic lesions of the hyperlipidemic mice.

The LDL receptor is the major pathway for beta-VLDL uptake by mouse peritoneal macrophages.

In order to determine the contribution of the low density lipoprotein receptor (LDL-R) to the removal of apoB-containing native lipoproteins by macrophages, we compared the uptake of beta-VLDL in peritoneal macrophages (MPM) from wild type mice and mice lacking the LDL-R. The d<1.006 g/ml lipoproteins obtained from apoE deficient mice fed a high fat diet were poorly degraded by macrophages and caused only a slight formation of CE in macrophages from both types of mice. On the other hand, d<1.006 g/ml lipoproteins obtained from LDL-R deficient mice fed a high fat diet, beta-VLDL with apoE, were avidly taken up by and markedly stimulated CE formation in wild type macrophages, but not in macrophages lacking the LDL-R. The degradation of 125I-labeled-apoE-containing beta-VLDL by wild type MPM was poorly inhibited by unlabeled human LDL, and beta-VLDL without apoE had no effects. In conclusion, we propose that the in vitro uptake of native apoE-enriched lipoproteins by murine macrophages is primarily mediated by the LDL receptor and not by other apoE-recognizing receptor systems such as: the LDL receptor related protein, the VLDL receptor or the triglyceride-rich lipoprotein receptor.

Thiazolidinedione- and tumor necrosis factor alpha-induced downregulation of peroxisome proliferator-activated receptor gamma mRNA in differentiated 3T3-L1 adipocytes.

Thiazolidinediones (TZDs) are antidiabetic insulin-sensitizing agents that bind to peroxisome proliferator-activated receptor gamma (PPARgamma) and have potent adipogenic effects on 3T3-L1 preadipocytes. In fully differentiated 3T3-L1 adipocytes, TZDs markedly decreased PPARgamma mRNA levels without reducing the expression of genes that are positively regulated by PPARgamma, such as adipocyte lipid-binding protein 2 (aP2) or lipoprotein lipase-(LPL). PPARgamma mRNA levels were also downregulated by tumor necrosis factor alpha (TNFalpha), an antiadipogenic cytokine. We propose that the downregulation of PPARgamma is not the common denominator of the metabolic effects of TZDs and TNFalpha on mature adipocytes.

Correlation between serum cytokeratin 19 fragment and tissue polypeptide antigen levels in patients with non-small cell lung cancer.

We evaluated the correlation between serum cytokeratin 19 fragment (CYFRA 21-1) and tissue polypeptide antigen (TPA) levels in 57 non-small cell lung cancer patients. There was a significant correlation between serum CYFRA 21-1 and TPA levels for each clinical stage and TNM (T, primary tumor; N, regional lymph node involvement; M, occurrence of distant metastasis) subcategory (range of r-value = 0.809-0.998, P < 0.01). High correlations between serum CYFRA 21-1 and TPA levels were found in eight patients both before and after the surgery, in 22 patients before and after chemotherapy and in another 27 patients who could not complete the scheduled chemotherapy (range of r-value = 0.856-0.998, P < 0.0001). However the positive rate of CYFRA 21-1 was higher than that of TPA (61% vs. 53%, P < 0.05). CYFRA 21-1 would yield better diagnostic results for non-small cell lung cancers than TPA, though these tumor markers are both cytokeratin-associated tumor markers.

Changes in squamous cell carcinoma-related antigen levels before and after hemodialysis in relation to the model of dialyzer employed.

OBJECTIVE: Although tumor marker levels in blood become elevated after hemodialysis as a result of the amount of fluid removed, serum squamous cell carcinoma-related antigen (SCC) levels have not been always reported to increase after hemodialysis. The purpose of this report is to determine whether there is a difference between the change of serum SCC levels before and after hemodialysis according to the model of dialyzer employed. PATIENTS AND METHODS: In ninety-four patients on hemodialysis (50 cases of diabetic nephropathy and 44 cases of glomerulonephritis), we examined serum SCC levels before and after hemodialysis. RESULTS: There was no overall difference between SCC levels before and after hemodialysis (3.2+/-1.5 ng/ml vs 3.3+/-1.7 ng/ml, p=0.2381). In patients treated with a cellulosic type membrane dialyzer (n=73), SCC levels after hemodialysis were higher than those before hemodialysis (3.7+/-1.7 ng/ml vs 3.5+/-1.5 ng/ml, p=0.0495). In patients treated with a synthetic type membrane (n=21), SCC levels after hemodialysis decreased when compared to those before hemodialysis (1.9+/-0.7 ng/ml vs 2.2+/-0.8 ng/ml, p=0.0018) and in all patients, the SCC levels after hemodialysis were lower than, or equal to, those before hemodialysis. CONCLUSION: The results suggest that the decline in serum SCC levels during hemodialysis treated with synthetic type membrane of dialyzers, concealed the increased SCC levels in hemoconcentration.

Cancer-associated retinopathy during treatment for small-cell lung carcinoma.

A 70-year-old woman with small-cell lung carcinoma (c-T4N2M0) was treated by six courses of combination chemotherapy (carboplatin and etoposide). After two weeks, she complained of a sense of darkness and night blindness. A Western blot analysis showed that the patient's serum bound with the recombinant 23-kDa retinal cancer-associated retinopathy (CAR) antigen at 1:1,000 dilution. Her visual acuity became so poor that she could only recognise a hand motion at 50 cm despite treatment with corticosteroids and combination chemotherapy. The patient was diagnosed as having a rare type of CAR because CAR is usually found before the diagnosis of primary cancer.

Sarcoidosis with multiple nodular shadows in bilateral lung fields.

Sarcoidosis is a disease of unknown etiology which is characterized pathologically by wide-spread non-caseating granulomas involving multiple organ systems. We report a case of sarcoidosis with multiple nodular shadows in bilateral lung fields. Abnormal shadows were completely disappeared without medication after one six months.

Mechanism of increased serum cytokeratin 19 fragment levels in patients with diabetic nephropathy as a model of chronic renal failure.

We examined serum and urinary cytokeratin 19 fragment (CYFRA 21-1) levels in patients with diabetic nephropathy as a model of chronic renal failure, to investigate the mechanism of increased serum CYFRA 21-1 levels in chronic renal failure. Serum and urinary CYFRA 21-1 levels in non-insulin-dependent diabetes mellitus (NIDDM) patients with abnormal urinary immunoglobulin G (IgG) levels (>1.1 mg/g x Cr, n=126) were higher than those with normal urinary IgG levels. In NIDDM patients with normal urinary IgG levels (n=81); the urinary albumin or transferrin levels were not related to serum or urinary CYFRA 21-1 levels. We speculate that the increased serum CYFRA 21-1 levels contribute to metabolic abnormality in the kidney itself rather than the decreased urinary excretion per se, and that increased urinary CYFRA 21-1 levels are found in advanced cases of diabetic nephropathy with destruction of the size barrier.

Ki-1 (CD30)-positive anaplastic large cell lymphoma, sarcomatoid variant accompanied by spontaneously regressing lymphadenopathy.

Although it has been reported that primary Ki-1 (CD30)-positive anaplastic large cell lymphoma (ALCL) of the skin may undergo spontaneous regression, it is rare for ALCL without cutaneous involvement to have spontaneously regressing lymphadenopathy. We report a case of sarcomatoid variant of ALCL accompanied by spontaneously regressing lymphadenopathy. The patient had gastric and pulmonary involvement of ALCL in addition to systemic lymphadenopathy, but with no cutaneous involvement. The lymphadenopathy spontaneously improved gradually during a period of one month without any treatment. At the same time, multiple small nodules in both lung fields decreased on chest computed tomography and multiple elevated gastric tumors with dimples were endoscopically recognized to have improved. He has since been treated with combination chemotherapy because of recurrence of the lymphadenopathy.

Malignant solitary fibrous tumor arising in the right buttock associated with metastatic parietal pleural and intrapulmonary tumors in addition to pleural effusion.

A malignant solitary fibrous tumor arising in the right buttock associated with metastatic parietal pleural and intrapulmonary tumors and pleural effusion was found in a 59-year-old man. A chest computed tomogram revealed three tumors attached to the parietal pleura with rib destruction, and a tumor in the left lower lung field. Histologically, the tumors of the buttock and parietal pleura were characterized by proliferation of bundles of spindle-shaped or oval cells separated by wavy hyalinized collagen tissue with no expression of cytokeratin, S-100 protein, muscle actin or epithelial membrane antigen, but these cells weakly expressed CD34 and strongly expressed vimentin.

[Mixed connective tissue disease-associated interstitial pneumonia complicated by pneumomediastinum during prednisolone therapy].

A 59-year-old woman was admitted to our hospital with exertional dyspnea. Linear and reticular opacities in the middle and lower fields of both lungs were observed on chest roentgenograms and chest computed tomograms (CT). The presence of anti RNP-antibody and Raynaud's phenomenon, sclerosis of the fingers, and leukopenia yielded a diagnosis of mixed connective tissue disease associated with interstitial pneumonia. The symptoms and lung involvement were alleviated after the administration of prednisolone (40 mg/day). However, the patient experienced the sudden onset of dyspnea during pulmonary function tests. A chest X-ray film disclosed mediastinal air around the left pulmonary artery, and a chest CT scan demonstrated some blebs in the left lower lung field. After tapering the dosage of prednisolone in 5 mg increments per week, the pneumomediastinum disappeared without treatment. The clinical features and laboratory data findings suggested the patient's interstitial pneumonia was associated with systemic lupus erythematosus rather than with progressive systemic sclerosis or dermatomyositis. The pneumomediastinum may have been due to the rupture of blebs secondary to interstitial pneumonia during pulmonary function tests or as a result of steroid therapy.

[Holter electrocardiogram monitoring as an indicator of cardiac involvement of sarcoidosis].

Sarcoidosis was diagnosed in a 55-year-old non-smoking woman because biopsy specimens of a subcutaneous tumor in her right cheek disclosed a noncaseating epithelioid granuloma. The patient had experienced exertional dyspnea and palpitation. Two months later, she was admitted because a Holter electrocardiogram (ECG) revealed bradycardia, 2:1 atrioventricular block (Mobitz II type) and ventricular premature beat (1.091 beats/day). ECG findings on admission changed from 2nd-degree to 3rd-degree atrioventricular block. A permanent pacemaker was implanted and the patient's symptoms subsided. Mediastinal uptake of Gallium-67 was observed and a defect of the cardiac septum was disclosed by Thalium-201 scintigram. Closer examination of the first Holter ECG revealed a Mobitz II type 2:1 atrioventricular block for about 3 minutes a day. Although the findings of the first Holter ECG initially disclosed a 2nd-degree atrioventricular block in our patient, a complete block developed within about 2 months after admission. In the follow-up of sarcoidosis patients, it therefore seems important to not only evaluate Holter ECG findings carefully, but repeat the examination at regular intervals.

[Increased neuron-specific enolase levels in patients with long-standing pyothorax-associated lymphoma].

A 78-year-old man was admitted for the evaluation of chest pain and a subcutaneous giant mass in the left chest, which had been growing for 3 months. A computed tomogram of the chest revealed a giant tumor attached to the parietal pleura with calcification of long-standing pyothorax. Pathological findings of a specimen obtained from this tumor showed diffuse proliferation of large atypical lymphocytes with 1-2 nucleoli and abundant cytoplasm. In immunohistochemical studies, tumor cells stained positive for CD20 but not for CD45 RO. The diagnosis was long-standing pyothorax-associated lymphoma (diffuse large-cell lymphoma, B-cell type). The patient's serum neuron-specific enolase (NSE) level was 101 ng/ml on admission, and declined in tandem with a chemotherapy-induced decrease in tumor size. In addition, immunohistochemical studies showed staining of tumor cells by anti-NSE polyclonal antibody. Although rarely observed in patients with malignant lymphoma, increased serum NSE levels may serve as an index of chemotherapeutic effectiveness.

[Motor neuron disease with respiratory insufficiency as primary manifestation].

A 66-year-old man with dyspnea on exertion suffered a cardiac arrest and was referred to our hospital after emergency room intubation. Chest X-ray films detected no abnormalities. Blood gas analysis showed hypoxemia with normal A-aDO 2, and pulmonary function tests revealed combined ventilatory impairment. Chest fluoroscopy revealed weakness of diaphragmatic motion. No other abnormalities were found on initial examination. It was difficult to wean the patient off mechanical ventilation and identify the cause of alveolar hypoventilation. On the 60th hospital day, a neurological examination and electromyography disclosed fasciculation and denervation of the left biceps and pectoralis major muscle. These findings supported the diagnosis of motor neuron disease (MND). Although respiratory insufficiency as an initial symptom of MND is unusual, physicians should be aware of the possibility of MND in cases of alveolar hypoventilation of unknown etiology.

[The relationship of carcinoembryonic antigen and neutrophils to pulmonary function in healthy smokers].

We evaluated the relationship of carcinoembryonic antigen (CEA) and neutrophils to pulmonary function in healthy smokers. Smokers in whom levels of CEA were greater than 5.0 ng/ml (n = 70) and in whom CEA levels were 5.0 ng/ml or less (n = 693) had significantly higher mean concentrations of leukocytes and neutrophils than non-smokers (n = 651) (leukocytes: 6,883 +/- 1,889/mm3 or 5,581 +/- 1,457/mm3 vs. 4,507 +/- 1,111/mm3, p < 0.01; neutrophils: 4,389 +/- 1,542/mm3 or 3,343 +/- 1,164/mm3 vs. 2,700 +/- 884/mm3, p < 0.01). Differences in the ratio of vital capacity to the predicted vital capacity (%VC) were not significant. In addition, the ratio of forced expiratory volume in one second to forced vital capacity (FEV 1.0%) in smokers with CEA levels greater than 5.0 ng/ml was decreased compared with smokers with CEA levels of 5.0 ng/ml or less and in non-smokers (90.2 +/- 8.4% vs. 93.3 +/- 6.7% or 92.9 +/- 6.5%, p < 0.01). These results suggest that in healthy smokers high serum CEA levels are related to a decreased FEV 1.0%.

[Clinical usefulness of serum assay of EIA-CYFRA 21-1 in lung cancer].

Enzyme immunoassay CYFRA 21-1, a novel lung tumor marker presented in serum (upper limit of normal values: 3.5 ng/ml) was measured in 84 patients with lung cancer and 141 patients with benign respiratory diseases. The positive rate for CYFRA 21-1 in primary lung cancer was 70.3% and the false positive rate in respiratory diseases was 24.1%. In respect to the histological types of lung cancer, CYFRA 21-1 was elevated in 85.0% of squamous cell carcinoma and in 64.8% of other cell types of primary lung cancer. Elevated CYFRA 21-1 levels were found in 40% of Stage I-II, in 80.0% of Stage IIIA-B, and in 73.5% of Stage IV. The overall diagnostic efficiency was 53.4% for CYFRA 21-1 and 44.5% for CEA, respectively. Receiver operating characteristic (ROC) curve analysis suggested that CYFRA 21-1 test has an advantage over CEA. From the results of this study, CYFRA 21-1 was more efficient than CEA as primary diagnostic marker in lung cancer.

[Three cases of semi-invasive pulmonary aspergillosis occurring in healthy or diabetic individuals].

We encountered three cases of suspected semi-invasive pulmonary aspergillosis, occurring in healthy or diabetic patients. Radiographic findings disclosed cavity formation in 2 of the patients, but only nodular lesions in 1. The beta-D glucan level was elevated in 1 patient, but was within the normal range in the other 2. Morphological findings indicated that all 3 patients had pulmonary aspergillosis. Following the oral administration of FLCZ to 1 patient and ITCZ to the other 2 for about 2 months, the radiographic lesions resolved and hematologic inflammatory reactions cleared up. Gefter et al and Sider et al have defined 2 types of aspergillosis that occur in mildly immuno-compromised or healthy individuals: the semi-invasive type, which destroys pulmonary tissue without vascular invasion and leads to cavity formation; and the locally invasive type, which is characterized by nodular or massive radiographic lesions without cavity formation. Semi-invasive aspergillosis was diagnosed in all 3 of the cases we reported.