Evaluation of the Virus-elimination Efficacy of Nanofiltration (Viresolve NFP) for the Parvovirus B19 and Hepatitis A Virus / 대한진단검사의학회지

BACKGROUND: The safety of plasma derivatives has been reinforced since 1980s by variable pathogen inactivation or elimination techniques. Nucleic acid amplification test (NAT) for the source plasma has also been implemented worldwide. Recently nanofiltration has been used in some country for ensuring safety of plasma derivatives to eliminate non-enveloped viruses such as parvovirus B19 (B19V) and hepatitis A virus (HAV). We evaluated the efficacy of nanofiltration for the elimination of B19V and HAV. METHODS: To verify the efficacy of nanofiltration, we adopted a 20 nm Viresolve NFP (Millipore, USA) in the scaling down (1:1,370) model of the antithrombin III production. As virus stock solutions, we used B19V reactive plasma and porcine parvovirus (PPV) and HAV obtained from cell culture. And 50% tissue culture infectious dose was consumed as infectious dose. The methods used to evaluate the virus-elimination efficacy were reverse-transcriptase polymerase chain reaction for B19V and the cytopathic effect calculation after filtration for PPV and HAV. RESULTS: B19V was not detected by RT-PCR in the filtered antithrombin III solutions with initial viral load of 6.42x10(5) IU/mL and 1.42x10(5) IU/mL before filtration. The virus-elimination efficacy of nanofiltration for PPV and HAV were > or =10(3.32) and > or =10(3.31), respectively. CONCLUSIONS: Nanofiltration would be an effective method for the elimination of B19V and HAV. It may be used as a substitute for NAT screening of these viruses in source plasma to ensure safety of plasma derivatives in Korea.

Characterization of Binding and Phagocytosis of Oxidatively Damaged Erythrocyte to Macrophage

BACKGROUND: Scavenger receptors are thought to be involved in the recognition of oxidized low-density lipoprotein (oxLDL) and oxidized erythrocyte (oxRBC). However, there are controversies about the kind of receptors and ligands related to the binding. Macrophages lacking class A scavenger receptor show identical binding of oxRBC with wild-type ones. METHODS: RBCs were oxidized with ascorbic acid and CuSO4. Lipid oxidation was measured indirectly by measuring TBARS semiquantitatively. The binding and phagocytosis were measured by counting the number of oxRBC bound or taken up after incubation at 4 degrees C or 37 degrees C for 60 minutes to 100 macrophages differentiated from human monocytic leukemia cell line. RESULTS: The degree of oxidation and the binding of oxRBCs were dependent on the concentration of CuSO4. The binding and phagocytosis of oxRBC were inhibited by 99% with oxLDL. Fucoidan, competing class A scavenger receptor, inhibited the binding by more than 90%. The binding of oxRBC was higher at 37 degrees C than at 4 degrees C by 3 times. The binding of oxRBCs was maximal at pH 6.5 and higher than at physiologic pH by 2.8 times. At pH 8.5 and 9.5, binding decreased by 67 and 88%, respectively. CONCLUSION: OxRBCs might bind and be taken up to macrophages not mainly through class A nor B scavenger receptors, but through other scavenger receptors and/or pathways. These processes are dynamic and ionic strength might be involved.

Expressional Change of Endothelial Nitric Oxide Synthase in Rat Cerebral Cortex after Kainic Acid-Induced Seizure / 대한해부학회지

Administration of kainic acid (KA) results in induction of epileptiform activity and motor seizures. Nitric oxide (NO) mediates the increase in cerebral blood flow during seizure activity. However, the production site of NO has not been clearly defined. Recent studies showed that constitutive nitric oxide synthase may be induced under certain conditions. Therefore, this study was aimed to investigate the change in endothelial nitric oxide synthase (eNOS), neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) since these are involved in cerebral blood flow. Rats were treated with KA and killed at 6 hours, 1, 3, 6 and 12 days after seizure. Expressional changes were assessed by immunohisto-chemistry and RT-PCR. eNOS was detected in the blood vessels of the cerebral cortex of the control group, but was not detected in neurons. eNOS-positive neurons were induced in the cerebral cortex at 1 and 3 days after seizure and found in specific cortical areas, such as primary motor cortex, secondary motor cortex, primary somatosensory cortex, secondary somatosensory cortex, insular cortex, ectorhinal cortex, parietal association cortex, temporal association cortex, auditory cortex and visual cortex. The levels of eNOS mRNA increased at 1 and 3 days after seizure compared to controls. The staining intensity of eNOS-positive microvessels was elevated in samples obtained 1, 3, and 6 days after seizure compared to the control group. However, NPY- and VIP-positive neurons, and glial fibrillary acidic protein-positive astrocytes were not induced in the cerebral cortex after seizure. Therefore, specific neuroactive substances may be induced in the cerebral cortex after seizure. Nitric oxide, a free radical synthesized in the brain by NOS, is a messenger molecule that mediates vascular dilatation and neural transmission. Therefore, neurons showing induced eNOS-positivity and upregulated eNOS-positive microvessels may affect the cerebral blood flow and neuronal activity in the cerebral cortex after seizure.

A Case of Cardiac Chloroma Complicated by Acute Lymphocytic Leukemia

Chloroma (granulocytic sarcoma) indicates an extramedullary leukemic cell collection. It often develops in the course of, or as a presenting sign of leukemia. Cardiac chloroma is uncommon and rarely detected as a mass. We report the first case of cardiac chloroma in a patient with acute lymphocytic leukemia in Korea. A 73-year-old man was admitted because of exertional dyspnea, orthopnea and generalized weakness. Thrombocytopenia and immature leukocytes were detected in the peripheral blood. An X-ray film of the chest showed mild cardiome-galy and bilateral pleural effusion. Transthoracic and transesophageal echocardiography showed a low echogenic mass at the lateral wall of the right ventricle. The size of the mass was about 6x4 cm. MRI of the chest showed right ventricular mass with slightly increased inhomogeneous signal intensity. Bone marrow aspiration and biopsy confirmed that he had a L3 FAB subtype of acute lymphocytic leukemia. Induction chemotherapy with vincristine, prednisolone, daunorubicin resulted in hematologic complete remission. At 6 weeks after the induction chemotherapy, transesophageal echocardiography demonstrated disappearance of the right ventricular mass which suggested that it was a cardiac chloroma complicating acute lymphocytic leukemia.

Effects of Angiotensin II on the Growth of Vascular Smooth Muscle Cells

BACKGROUND AND OBJECTIVES: The octapeptide hormone of the renin-angiotensin system, angiotensin ii, regulates a wide variety of physiological responses including salt and water balance, blood pressure, and vascular tone. Contradictory results have been reported regarding the effects of angiotensin ii on vascular smooth mu-scle cell (VSMC) proliferation. The aim of the present study was to investigate the direct effect of angiotensin ii on the growth of VSMC. MATERIALS AND METHOD: Rat aortic smooth muscle cells were obtained by the combined collagenase and elastase methods. Cells between the 4th and 8th passages were used for the experiments. Cultures were treated daily for 3 days with either angiotensin ii alone or angiotensin ii with equimolar concentrations of saralasin. Incorporated radioactivity of [3H]thymidine and [14C]phenylalanine was measured by liquid scintillation spectrometry. RESULTS: Angiotensin ii increased [14C]phenyalanine incor-poration about 20-30%, and saralasin completely blocked the stimulation by angiotensin ii. However, there was no significant increase in [3H]thymidine incorporation by angiotensin ii stimulation in this study. CONCLUSION: These results suggest that angiotensin ii alone induces cellular hypertrophy but has no detectable mitogenic activity in cultured rat aortic VSMC.

Effect of Carvedilol on the Growth of Vascular Smooth Muscle Cells

Background and objectives: Carvedilol is a cardiovascular drug, beta- and alpha1-adrenoceptor antagonist, currently approved for the treatment of hypertension, angina, congestive heart failure by FDA. Carvedilol has been shown to attenuate oxygen free radical-initiated lipid peroxidation and to inhibit neointimal formation of aorta following vascular injury by balloon angioplasty. We have investigated the effect of carvedilol on DNA synthesis of vascular smooth muscle cells (VSMC) stimulated by platelet-derived growth factor (PDGF)-BB. MATERIALS AND METHOD: Rat aortic smooth muscle cells were obtained by the combined collagenase and elastase methods. Cells between the 4th and 8th passages were used for the experiments. Incorporated radioactivity of [3H]-thymidine was measured by liquid scintillation spectrometry. RESULTS: PDGF-BB (1 nM) increased [3H]-thymidine incorporation about 70-100% over basal value in cultured VSMC. PDGF-stimulated increase in DNA synthesis was significantly suppressed by simultaneous administration of carvedilol. In contrast, propranolol did not significantly affect 3[H]-thymidine uptake in rat aortic VSMC. CONCLUSION: The present study demonstrate that carvedilol significantly inhibits the proliferation of vascular smooth muscle cell in our condition. These results indicate that carvedilol may be effective in the treatment of cardiovascular diseases principally associated with abnormal vascular smooth muscle growth.

Association of Carotid Artery Intimal-Medial Thickness with Left Ventricular Hypertrophy

BACKGROUND: Atherosclerosis is a diffuse disease process that produce thickening of the vascular wall because of intimal deposition of lipid, fibrous tissue, and calcific material. Nowadays it is possible to evaluate atherosclerotic changes of carotid arteries accurately by developed noninvasive techniques such as ultrasonography. Left ventricular hypertrophy (LVH) is known to be an important risk factor for cardiovascular events in hypertension. The purpose of this study was to establish whether the carotid intimal - medial thickness (IMT) correlates with the severity of LVH. METHOD: We measured intimal-medial thickness (IMT) for 12 sites in carotid arteries (near and far walls in common carotid, bifurcation, and internal carotid arteries of both sides) by B-mode ultrasonography in both 38 normotensive and 72 hypertensive patients. Left ventricular measurements were made according to the recommendations of the American Society of Echocardiography. Left ventricular mass was derived from the formula described by Devereux et al. and each left ventricular mass value was indexed to body surface area. And then we have investigated whether hypertensive patients have significant changes of carotid IMT and IMT correlates with left ventricular mass index (LVMI). RESULTS: (1) Most hypertensive patients had diffuse thickening of the carotid artery and some had focal or multiple plaques. (2) In general, mean IMT was widest in the carotid bifurcation. (3) The mean IMT of all 12 segments increased about 40% in hypertensive patients compared with normal control group. (4) LVMI significantly correlates with IMT of carotid artery, especially bifurcation site and mean all 12 segments. CONCLUSION: The mean IMT may serve as a useful marker of the severity of atherosclerosis in hypertensive patients. The significant association between carotid IMT and LVMI suggests a simultaneous correlation of carotid atherosclerosis with left ventricular hypertrophy in hypertension.

Ultrastructural Changes of the Aorta in Spontaneously Hypertensive Rats and the Effect of High Cholesterol Diet

BACKGROUND: Vascular lesions are the major cause of morbidity and mortality in hypertensive patients. However, the pathologic characteristics of gradually evolving, chronic hypertension have not been adequately studied and the mechanism by which hypertension accelerates atherosclerosis is still uncertain. This study was undertaken to invertigate the ultrastructural changes of the aorta and the effect of high cholesterol diet in spontaneously hypertensive rats(SHR). METHODS: Spontaneously hypertensive rats (n=80, male, 5 weeks old) and Wistar rats (n=40, male, 5 week old) were used. Forty SHR were fed with 2% cholestrol diete, while the remainder with control diet. Systolic blood pressure was measured weekly until 16 weeks after birth, and then biweekly until 40 weeks after birth. Transmission and scanning electron microscopy were used to evaluate ultrastrucural changes of the aorta. RESULTS: 1) The blood pressure of SHR rose stedily and progressively from the 5 weeks after birth and reached nearly 190mmHG at the 16 weeks after birth. 2) In SHR, the subendothelial component contained finely granular substances, abundant fibrillar collagen and elastin. Infiltration of the mononuclear blood leukocytes into the intima was frequently seen. 3) Endothelium from cholestrol-fed SHR did exhibit numerous pinocytotic vesicles and contained many cytoplasmic filaments. There were a number of large mononuclear lipid-filled cells in the intimal lesions. Blistering of the endothelial plasma membrane was also observed in high cholesterol diet-fed SHR. Later on, adhesion of platelets, febrin, and white blood cells as well as damage of intima shown as multiple small holes were more marked. 4) There was no significant difference in systoloic blood pressure between high cholesterol diet-fed and control diet-fed SHR. CONCLUSION: In the aorta of SHR, the most prominent change was an expansion of the subendothelial space and infiltration of the mononuclear leukocytes into the intima. The present study showed that the SHR was indeed a reliable model for the essential hypertension. In some SHR, high cholesterol diet could induce more pronounced vascular lesions, which were enhanced by hypertension.